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2,502 | 200 | 22136061 | For what is Protein A from Staphylococcus aureus used in biochemistry? | Molecular mechanism of the effects of salt and pH on the affinity between protein A and human immunoglobulin G1 revealed by molecular simulations. Protein A from the bacterium Staphylococcus aureus (SpA) has been widely used as an affinity ligand for purification of immunoglobulin G (IgG). The affinity between SpA and IgG is affected differently by salt and pH, but their molecular mechanisms still remain unclear. In this work, molecular dynamics simulations and molecular mechanics Poisson-Boltzmann surface area analysis were performed to investigate the salt (NaCl) and pH effects on the affinity between SpA and human IgG1 (hIgG1). It is found that salt and pH affect the interactions of the hot spots of SpA by different mechanisms. In the salt solution, the compensations between helices I and II of SpA as well as between the nonpolar and electrostatic energies make the binding free energy independent of salt concentration. At pH 3.0, the unfavorable electrostatic interactions increase greatly and become the driving force for dissociation of the SpA-hIgG1 complex. They mainly come from the strong electrostatic repulsions between positively charged residues (H137, R146, and K154) of SpA and the positively charged residues of hIgG1. It is considered to be the molecular basis for hIgG1 elution from SpA-based affinity adsorbents at pH 3.0. The dissociation mechanism is then used to refine the binding model of SpA to hIgG1. The model is expected to help design high-affinity peptide ligands of IgG. |
2,510 | 201 | 19929882 | What is the suggested therapy for Mycobacterium avium infection? | Nontuberculous mycobacterial pulmonary infection in renal transplant recipients. The most common presentations of nontuberculous mycobacterial infections in kidney transplant recipients (KTR) are cutaneous and disseminated diseases. Pleuropulmonary infection not associated with disseminated disease is rare. Its diagnosis can be difficult, requiring a combination of clinical, radiological, and bacteriological criteria. We report on a Mycobacterium avium complex pulmonary infection in a KTR with underlying chronic obstructive pulmonary disease. Chest computed tomography showed an excavated lesion of the right upper lobe, similar to a typical lesion of pulmonary tuberculosis. Evolution was favorable with multiple-drug therapy including rifampicin, ethambutol, and clarithromycin, along with a slight reduction in immunosuppression. We review the literature and discuss the epidemiology, diagnosis, management, and follow-up of this uncommon post-transplant complication. |
2,518 | 202 | 18924029 | What is the treatment of acute pericarditis? | [Myopericarditis complicated with cardiogenic shock mimicking acute coronary syndrome with ST elevation in a patient with hyperthyroidism and diabetes mellitus]. We describe a case of a 56 year old man with myopericarditis complicated with cardiogenic shock within first 3 days, mimicking on admission acute myocardial infarction with ST elevation in inferior ECG leads. Additionally, patient presented hyperthyroidism and totally decompensated diabetes mellitus. He required during the first 3 days intravenous infusion of inotropic agents. Cardiac enzymes levels were elevated. Akinesia in mid-inferior and mid-posterior regions in ECHO was observed. On the 10th day ST segment elevation in I, II, V3-V6 and ST depression in aVR was observed in ECG. After stabilisation patient underwent coronarography which showed normal coronary arteries. The final diagnosis was acute myopericarditis complicated with acute heart failure and cardiogenic shock. |
2,531 | 203 | 24105488 | What is the genetic basis of tuberous sclerosis? | Subependymal giant cell astrocytomas in patients with tuberous sclerosis complex: considerations for surgical or pharmacotherapeutic intervention. Tuberous sclerosis complex is a genetic disorder caused by mutations in either the TSC1 or TSC2 gene that can result in the growth of hamartomas in multiple organ systems. Subependymal giant cell astrocytomas are slow-growing brain tumors associated primarily with tuberous sclerosis complex. They are usually located in the ventricles, often near the foramen of Monro, where they can cause an obstruction if they grow too large, leading to increased intracranial pressure. Surgery to remove a tumor has been the mainstay of treatment but can be associated with postoperative morbidity and mortality. Not all tumors and/or patients are suitable for surgery. The recent development of mammalian target of rapamycin inhibitors that target the pathway affected by TSC1/TSC2 mutations offers a novel pharmacotherapeutic option for these patients. We review the timing and use of surgery versus pharmacotherapy for the treatment of subependymal giant cell astrocytoma in patients with tuberous sclerosis complex. |
2,540 | 204 | 16263726 | What is the molecular function of the Chd1 protein? | Human but not yeast CHD1 binds directly and selectively to histone H3 methylated at lysine 4 via its tandem chromodomains. Defining the protein factors that directly recognize post-translational, covalent histone modifications is essential toward understanding the impact of these chromatin "marks" on gene regulation. In the current study, we identify human CHD1, an ATP-dependent chromatin remodeling protein, as a factor that directly and selectively recognizes histone H3 methylated on lysine 4. In vitro binding studies identified that CHD1 recognizes di- and trimethyl H3K4 with a dissociation constant (Kd) of approximately 5 microm, whereas monomethyl H3K4 binds CHD1 with a 3-fold lower affinity. Surprisingly, human CHD1 binds to methylated H3K4 in a manner that requires both of its tandem chromodomains. In vitro analyses demonstrate that unlike human CHD1, yeast Chd1 does not bind methylated H3K4. Our findings indicate that yeast and human CHD1 have diverged in their ability to discriminate covalently modified histones and link histone modification-recognition and non-covalent chromatin remodeling activities within a single human protein. |
2,550 | 205 | 8808724 | Which drugs are included in the FEC-75 regimen? | Prevention of delayed emesis by a single intravenous bolus dose of 5-HT3-receptor-antagonist in moderately emetogenic chemotherapy. While the use of 5-HT3 receptor antagonists is clearly justified in patients receiving cisplatin, their role with less emetic drugs is still not defined. The aim of our randomized study was to verify the efficacy of the single standard dose of three 5-HT3-receptor-antagonists in moderately emetic chemotherapies. Sixty chemotherapy-naive breast cancer patients of 30 to 71 years in age, P.S. = 0-1, receiving 5-fluorouracil-epirubicin-cyclophosphamide (FEC 75) q 21 days or cyclophosphamide-methotrexate-5-fluorouracil (CMF) or 120 mg/m2 epirubicin or high dose mitomycin-methotrexate-mitoxantrone (MMM) q 14 days (+ G-CSF) or 100 mg/m2 epirubicin (+ G-CSF) were randomized to receive, 15 min before chemotherapy, 8 mg i.v. bolus of ondansetron or 3 mg i.v. granisetron or 5 mg i.v. tropisetron and no further antiemetic therapy in the following days. 180 cycles were evaluable. Complete protection, (the absence of vomiting episodes,) was respectively 75%, 70% and 70% in the acute and 70%, 82%, 72% in the delayed phases, and an absence of nausea was 56%, 37% and 20% in the acute phase and 50%, 35% and 27% in the delayed, respectively. Complete response, (absence of vomiting and absence or mild nausea,) was 74%, 58.6% and 50.8% in the acute and 64%, 63.7%, 47.3% in the delayed phases, respectively. At the statistical analysis no significant differences between the three drugs were found regarding acute vomiting while ondansetron was superior to granisetron and tropisetron in acute (p = 0.018; p < 0.05) and delayed nausea (P = 0.104; p < 0.01). This activity is practically the same as that we reported (Ann Oncol 1994; 6, suppl 8: 204) with a loading dose on day 1 and maintenance for the following 2-5 days, but with a significantly favorable cost-benefit ratio. |
2,566 | 206 | 2303258 | Between which probes does the recurrent translocation breakpoint on chromosome 22 of neuroepithelioma lie? | The neuroepithelioma breakpoint on chromosome 22 is proximal to the meningioma locus. The recurrent translocation breakpoint on chromosome 22 of neuroepithelioma has been localized between two probes, D22S1 and D22S15, by both in situ hybridization and somatic cell hybrids. These two probes have further been shown to be genetically linked at theta = 0.0 and a lod score of 5.3. The two probes were unaffected by a partial deletion of the chromosome 22 long arm of a meningioma, showing that the meningioma locus is distal to that of the neuroepithelioma. |
2,567 | 207 | 18290900 | Does administration of triiodothyronine improve outcome following coronary artery bypass grafting? | Does perioperative administration of thyroid hormones improve outcome following coronary artery bypass grafting? The question addressed in this review is whether supplementation with thyroid hormones during the perioperative period improves the outcome of patients undergoing coronary artery bypass surgery. Altogether 88 relevant papers were identified using the below mentioned search, seven papers represented the best evidence to answer the question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results, and study weaknesses were tabulated. We conclude that although widespread interest has been shown on the use of thyroid hormones in the perioperative period, and the effect of cardiopulmonary bypass on thyroid hormone metabolism widely studied, there is no substantial evidence to justify routine use of thyroid hormones in patients undergoing coronary artery bypass grafting. |
2,579 | 208 | 22422841 | Which are the most widely used computational methods for the identification of CRMs (cis-regulatory modules)? | Unveiling combinatorial regulation through the combination of ChIP information and in silico cis-regulatory module detection. Computationally retrieving biologically relevant cis-regulatory modules (CRMs) is not straightforward. Because of the large number of candidates and the imperfection of the screening methods, many spurious CRMs are detected that are as high scoring as the biologically true ones. Using ChIP-information allows not only to reduce the regions in which the binding sites of the assayed transcription factor (TF) should be located, but also allows restricting the valid CRMs to those that contain the assayed TF (here referred to as applying CRM detection in a query-based mode). In this study, we show that exploiting ChIP-information in a query-based way makes in silico CRM detection a much more feasible endeavor. To be able to handle the large datasets, the query-based setting and other specificities proper to CRM detection on ChIP-Seq based data, we developed a novel powerful CRM detection method 'CPModule'. By applying it on a well-studied ChIP-Seq data set involved in self-renewal of mouse embryonic stem cells, we demonstrate how our tool can recover combinatorial regulation of five known TFs that are key in the self-renewal of mouse embryonic stem cells. Additionally, we make a number of new predictions on combinatorial regulation of these five key TFs with other TFs documented in TRANSFAC. |
2,586 | 209 | 22874562 | Which enzyme does MLN4924 inhibit? | Inactivation of the Cullin (CUL)-RING E3 ligase by the NEDD8-activating enzyme inhibitor MLN4924 triggers protective autophagy in cancer cells. The multiunit Cullin (CUL)-RING E3 ligase (CRL) controls diverse biological processes by targeting a mass of substrates for ubiquitination and degradation, whereas its dysfunction causes carcinogenesis. Post-translational neddylation of CUL, a process triggered by the NEDD8-activating enzyme E1 subunit 1 (NAE1), is required for CRL activation. Recently, MLN4924 was discovered via a high-throughput screen as a specific NAE1 inhibitor and first-in-class anticancer drug. By blocking CUL neddylation, MLN4924 inactivates CRL and causes the accumulation of CRL substrates that trigger cell cycle arrest, senescence and/or apoptosis to suppress the growth of cancer cells in vitro and in vivo. Recently, we found that MLN4924 also triggers protective autophagy in response to CRL inactivation. MLN4924-induced autophagy is attributed partially to the inhibition of mechanistic target of rapamycin (also known as mammalian target of rapamycin, MTOR) activity by the accumulation of the MTOR inhibitory protein DEPTOR, as well as reactive oxygen species (ROS)-induced stress. Moreover, the blockage of autophagy response enhances apoptosis in MLN4924-treated cells. Together, our findings not only reveal autophagy as a novel cellular response to CRL inactivation by MLN4924, but also provide a piece of proof-of-concept evidence for the combination of MLN4924 with autophagy inhibitors to enhance therapeutic efficacy. |
2,616 | 210 | 19920172 | Which protein has been found to interact with phospholamban (PLN) and is also an anti-apoptotic protein? | The anti-apoptotic protein HAX-1 is a regulator of cardiac function. The HS-1 associated protein X-1 (HAX-1) is a ubiquitously expressed protein that protects cardiomyocytes from programmed cell death. Here we identify HAX-1 as a regulator of contractility and calcium cycling in the heart. HAX-1 overexpression reduced sarcoplasmic reticulum Ca-ATPase (SERCA2) pump activity in isolated cardiomyocytes and in vivo, leading to depressed myocyte calcium kinetics and mechanics. Conversely, downregulation of HAX-1 enhanced calcium cycling and contractility. The inhibitory effects of HAX-1 were abolished upon phosphorylation of phospholamban, which plays a fundamental role in controlling basal contractility and constitutes a key downstream effector of the beta-adrenergic signaling cascade. Mechanistically, HAX-1 promoted formation of phospholamban monomers, the active/inhibitory units of the calcium pump. Indeed, ablation of PLN rescued HAX-1 inhibition of contractility in vivo. Thus, HAX-1 represents a regulatory mechanism in cardiac calcium cycling and its responses to sympathetic stimulation, implicating its importance in calcium homeostasis and cell survival. |
2,621 | 211 | 17853713 | Is long QT syndrome a cause for sudden cardiac death in athletes? | [Causes of sudden cardiac death in athletes]. INTRODUCTION: Sudden cardiac death in athletes is a growing problem, despite the huge existing knowledge in medicine and sports. EFFECTS OF VIGOROUS PHYSICAL ACTIVITY: In response to vigorous physical activity, the body undergoes profound morphologic and functional changes. These changes are usually healthy, but sometimes may gravitate to some cardiac diseases. But still, most saudden cardiac deaths are due to previous unknown diseases. CAUSES OF SUDDEN CARDIAC DEATH: The most common cause of sudden cardiac death in athletes is hypertrophic cardiomyopathy. Other reasons are congenital coronary artery anomalies, nivocarditis, dilatative cardiomyopathy, arrhythmogenic cardiomyopathy of the right ventricle, sarcoidosis, mitral valve prolapse, aortic valve stenosis, atherosclerosis, long QT syndrome, and blunt impact to the chest. CONCLUSION: Bearing in mind the above mentioned, more frequent physical examinations of athletes are recommended. |
2,635 | 212 | 22553468 | What is the clinical value of MammaPrint? | The 70-Gene Signature as Prognostic Factor for Elderly Women with Hormone Receptor-Positive, HER2-Negative Breast Cancer. BACKGROUND: The aim of this article was to evaluate the prognostic value of the MammaPrint(TM) signature in women $$ 60 years with invasive breast cancer. PATIENTS AND METHODS: 60 female patients were included in this prospective study. Eligibility criteria included: pT1c-3, pN0-1a, grade 2/3, hormone receptor-positive and HER2-negative tumor. The clinical risk was determined by Adjuvant! Online (AOL). RESULTS: 38 patients (63%) where considered to be low-risk patients by the 70-gene signature, while 22 (37%) were considered to be high-risk patients. No statistically significant differences between low- and high-risk groups could be detected for conventional prognostic parameters, particularly not for Ki-67. By AOL, 33 patients (55%) were considered to be at high risk, of which 20 had a discordant MammaPrint(TM) result. The discordance rate between the profile and AOL was 48%, which is higher than in previous publications. When the 70-gene signature was used in combination with the clinical risk assessment, the recommendation for adjuvant systemic treatment differed in 11 patients (18%). CONCLUSIONS: In the intermediate-risk subgroup, the 70-gene signature could be useful to decide in elderly patients whether they may benefit from adjuvant chemotherapy or not. Conventional clinicopathological factors were not suitable for a prediction of the 70-gene signature results in these patients. |
2,643 | 213 | 15888437 | Is protein M3/6 a dual specificity phosphatase? | Dynamic interaction between the dual specificity phosphatase MKP7 and the JNK3 scaffold protein beta-arrestin 2. JNK scaffold proteins bind JNK and upstream kinases to activate subsets of JNK and localize activated JNK to specific subcellular sites. We previously demonstrated that the dual specificity phosphatases (DSPs) MKP7 and M3/6 bind the scaffold JNK-interacting protein-1 (JIP-1) and inactivate the bound subset of JNK (1). The G protein-coupled receptor (GPCR) adaptor beta-arrestin 2 is also a JNK3 scaffold. It binds the upstream kinases ASK1 and MKK4 and couples stimulation of the angiotensin II receptor AT1aR to activation of a cytoplasmic pool of JNK3. Here we report that MKP7 also binds beta-arrestin 2 via amino acids 394-443 of MKP7, the same region that interacts with JIP-1. This region of MKP7 interacts with beta-arrestin 2 at a central region near the JNK binding domain. MKP7 dephosphorylates JNK3 bound to beta-arrestin 2, either following activation by ASK1 overexpression or following AT1aR stimulation. Initial AT1aR stimulation causes a rapid (within 5 min) dissociation of MKP7 from beta-arrestin 2. MKP7 then reassociates with beta-arrestin 2 on endocytic vesicles 30-60 min after initial receptor stimulation. This dynamic interaction between phosphatase and scaffold permits signal transduction through a module that binds both positive and negative regulators. |
2,653 | 214 | 20616184 | Are there focused databases from which you can retrieve gene expression data on renal disease? | Naturally occurring human urinary peptides for use in diagnosis of chronic kidney disease. Because of its availability, ease of collection, and correlation with physiology and pathology, urine is an attractive source for clinical proteomics/peptidomics. However, the lack of comparable data sets from large cohorts has greatly hindered the development of clinical proteomics. Here, we report the establishment of a reproducible, high resolution method for peptidome analysis of naturally occurring human urinary peptides and proteins, ranging from 800 to 17,000 Da, using samples from 3,600 individuals analyzed by capillary electrophoresis coupled to MS. All processed data were deposited in an Structured Query Language (SQL) database. This database currently contains 5,010 relevant unique urinary peptides that serve as a pool of potential classifiers for diagnosis and monitoring of various diseases. As an example, by using this source of information, we were able to define urinary peptide biomarkers for chronic kidney diseases, allowing diagnosis of these diseases with high accuracy. Application of the chronic kidney disease-specific biomarker set to an independent test cohort in the subsequent replication phase resulted in 85.5% sensitivity and 100% specificity. These results indicate the potential usefulness of capillary electrophoresis coupled to MS for clinical applications in the analysis of naturally occurring urinary peptides. |
2,661 | 215 | 9367782 | What systems have been developed for the numbering of antibody residues? | Standard conformations for the canonical structures of immunoglobulins. A comparative analysis of the main-chain conformation of the L1, L2, L3, H1 and H2 hypervariable regions in 17 immunoglobulin structures that have been accurately determined at high resolution is described. This involves 79 hypervariable regions in all. We also analysed a part of the H3 region in 12 of the 15 VH domains considered here. On the basis of the residues at key sites the 79 hypervariable regions can be assigned to one of 18 different canonical structures. We show that 71 of these hypervariable regions have a conformation that is very close to what can be defined as a "standard" conformation of each canonical structure. These standard conformations are described in detail. The other eight hypervariable regions have small deviations from the standard conformations that, in six cases, involve only the rotation of a single peptide group. Most H3 hypervariable regions have the same conformation in the part that is close to the framework and the details of this conformation are also described here. |
2,674 | 216 | 22058406 | Are there any DNMT3 proteins present in plants? | In Posidonia oceanica cadmium induces changes in DNA methylation and chromatin patterning. In mammals, cadmium is widely considered as a non-genotoxic carcinogen acting through a methylation-dependent epigenetic mechanism. Here, the effects of Cd treatment on the DNA methylation patten are examined together with its effect on chromatin reconfiguration in Posidonia oceanica. DNA methylation level and pattern were analysed in actively growing organs, under short- (6 h) and long- (2 d or 4 d) term and low (10 μM) and high (50 μM) doses of Cd, through a Methylation-Sensitive Amplification Polymorphism technique and an immunocytological approach, respectively. The expression of one member of the CHROMOMETHYLASE (CMT) family, a DNA methyltransferase, was also assessed by qRT-PCR. Nuclear chromatin ultrastructure was investigated by transmission electron microscopy. Cd treatment induced a DNA hypermethylation, as well as an up-regulation of CMT, indicating that de novo methylation did indeed occur. Moreover, a high dose of Cd led to a progressive heterochromatinization of interphase nuclei and apoptotic figures were also observed after long-term treatment. The data demonstrate that Cd perturbs the DNA methylation status through the involvement of a specific methyltransferase. Such changes are linked to nuclear chromatin reconfiguration likely to establish a new balance of expressed/repressed chromatin. Overall, the data show an epigenetic basis to the mechanism underlying Cd toxicity in plants. |
2,689 | 217 | 18040051 | What is the number of protein coding genes in the human genome? | Distinguishing protein-coding and noncoding genes in the human genome. Although the Human Genome Project was completed 4 years ago, the catalog of human protein-coding genes remains a matter of controversy. Current catalogs list a total of approximately 24,500 putative protein-coding genes. It is broadly suspected that a large fraction of these entries are functionally meaningless ORFs present by chance in RNA transcripts, because they show no evidence of evolutionary conservation with mouse or dog. However, there is currently no scientific justification for excluding ORFs simply because they fail to show evolutionary conservation: the alternative hypothesis is that most of these ORFs are actually valid human genes that reflect gene innovation in the primate lineage or gene loss in the other lineages. Here, we reject this hypothesis by carefully analyzing the nonconserved ORFs-specifically, their properties in other primates. We show that the vast majority of these ORFs are random occurrences. The analysis yields, as a by-product, a major revision of the current human catalogs, cutting the number of protein-coding genes to approximately 20,500. Specifically, it suggests that nonconserved ORFs should be added to the human gene catalog only if there is clear evidence of an encoded protein. It also provides a principled methodology for evaluating future proposed additions to the human gene catalog. Finally, the results indicate that there has been relatively little true innovation in mammalian protein-coding genes. |
2,693 | 218 | 20796001 | Has vitamin D has been shown to reduce incidence of falls in older people in clinical trials? | Reducing fracture risk with calcium and vitamin D. Studies of vitamin D and calcium for fracture prevention have produced inconsistent results, as a result of different vitamin D status and calcium intake at baseline, different doses and poor to adequate compliance. This study tries to define the types of patients, both at risk of osteoporosis and with established disease, who may benefit from calcium and vitamin D supplementation. The importance of adequate compliance in these individuals is also discussed. Calcium and vitamin D therapy has been recommended for older persons, either frail and institutionalized or independent, with key risk factors including decreased bone mineral density (BMD), osteoporotic fractures, increased bone remodelling as a result of secondary hyperparathyroidism and increased propensity to falls. In addition, treatment of osteoporosis with a bisphosphonate was less effective in patients with vitamin D deficiency. Calcium and vitamin D supplementation is a key component of prevention and treatment of osteoporosis unless calcium intake and vitamin D status are optimal. For primary disease prevention, supplementation should be targeted to those with dietary insufficiencies. Several serum 25-hydroxyvitamin D (25(OH)D) cut-offs have been proposed to define vitamin D insufficiency (as opposed to adequate vitamin D status), ranging from 30 to 100 nmol/l. Based on the relationship between serum 25(OH)D, BMD, bone turnover, lower extremity function and falls, we suggest that 50 nmol/l is the appropriate serum 25(OH)D threshold to define vitamin D insufficiency. Supplementation should therefore generally aim to increase 25(OH)D levels within the 50-75 nmol/l range. This level can be achieved with a dose of 800 IU/day vitamin D, the dose that was used in successful fracture prevention studies to date; a randomized clinical trial assessing whether higher vitamin D doses achieve a greater reduction of fracture incidence would be of considerable interest. As calcium balance is not only affected by vitamin D status but also by calcium intake, recommendations for adequate calcium intake should also be met. The findings of community-based clinical trials with vitamin D and calcium supplementation in which compliance was moderate or less have often been negative, whereas studies in institutionalized patients in whom medication administration was supervised ensuring adequate compliance demonstrated significant benefits. |
2,701 | 219 | 20477251 | What is the indication for prophylactic use of antibiotics in COPD? | Role of antibiotics in the management of chronic obstructive pulmonary disease. Exacerbations of chronic obstructive pulmonary disease (COPD) are an important cause of morbidity and healthcare expenditure. In hospitalized patients, antibiotics decrease treatment failure and reduce mortality. There is also evidence for the effectiveness of antibiotics in treating COPD exacerbations in the community, but this is most convincing in patients with severe airflow obstruction and there is uncertainty regarding the value of antibiotics in patients with mild airflow obstruction. Treatment with antibiotics is usually recommended for patients who have an increase in sputum volume, sputum purulence and breathlessness, but the most important determinant of bacterial infection appears to be purulence. There is some evidence to suggest that the decision to use antibiotics can be guided by the use of procalcitonin, although this needs to be confirmed in further studies. Newer broad-spectrum antibiotics may be more effective than older antibiotics but, because of concerns regarding antibiotic resistance, it may be appropriate to reserve them for patients at highest risk of treatment failure. A number of studies suggest that antibiotic courses of 5 days in duration may be as effective as those for 7 days or more in patients with mild-to-moderate exacerbations of COPD. Guidelines do not recommend the use of prophylactic antibiotics in COPD but there is preliminary evidence to suggest that they may reduce the number of exacerbations. Until the full results of these studies are published, it will not be clear if they should be used. |
2,704 | 220 | 9520923 | Has depression been shown to be a predictor of frailty? | The structure of depression among elderly institution residents: affective and somatic correlates of physical frailty. BACKGROUND: Confounding of depression with somatic illness and anxiety, a problem in any age group, may be especially troublesome in frail older persons. This paper examined this problem in a factor analytic study of the structure of depressive symptomatology, identifying affective and somatic symptom clusters and relating those clusters to health and functional variables cross-sectionally and prospectively over a 1-year interval. METHODS: The factor structure of a DSM-IV symptom checklist was examined among 1,245 elderly long-term care residents. Regression analyses examined the association of resulting factors with cognition, functional disability, self- and physician-rated health, and pain at baseline and a year later. One-year mortality was also examined. RESULTS: Factor analysis revealed three unique symptom clusters: depressed mood, somatic symptoms, and psychic anxiety. Depressed mood and somatic symptoms were associated cross-sectionally with all functional health variables, but psychic anxiety was associated only with pain. Longitudinally, depressed mood was the only independent predictor of decline in cognition, functional ability, physician-rated health, and mortality; the last effect, however, did not withstand control for baseline health and functioning. Somatic symptoms at baseline predicted decrement in self-rated health a year later. Effects varied as a function of cognitive status. CONCLUSIONS: These data suggest that concerns about the confounding role of somatic symptoms in the association of depression with physical health are unfounded. Although somatic symptoms of depression and anxiety were associated with health and functional status cross-sectionally, depressed mood was by far the stronger predictor of health declines over time. |
2,709 | 221 | 24468659 | What is the generic name of Gliolan? | Cost-effectiveness of 5-aminolevulinic acid-induced fluorescence in malignant glioma surgery. OBJECTIVE: This study evaluates the cost-effectiveness of 5-aminolevulinic acid (5-ALA, Gliolan®) in patients undergoing surgery for malignant glioma, in standard clinical practice conditions in Spain. MATERIAL AND METHODS: Cost-effectiveness ratios were determined in terms of incremental cost per complete resection (CR) and incremental cost per additional quality-adjusted life year (QALY), based on data collected in the VISIONA observational study. RESULTS: Incremental cost with 5-ALA versus conventional surgery using white light only amounts to € 4550 per additional CR achieved and € 9021 per QALY gained. A sensitivity analysis shows these results to be robust. CONCLUSION: Malignant glioma surgery guided by 5-ALA fluorescence entails a moderate increase in hospital costs compared to current surgical practice and can be considered a cost-effective innovation. |
2,714 | 222 | 24856900 | Is there any association between Jarid2 and miR-155 in Th17 cells? | miR-155 activates cytokine gene expression in Th17 cells by regulating the DNA-binding protein Jarid2 to relieve polycomb-mediated repression. Specification of the T helper 17 (Th17) cell lineage requires a well-defined set of transcription factors, but how these integrate with posttranscriptional and epigenetic programs to regulate gene expression is poorly understood. Here we found defective Th17 cell cytokine expression in miR-155-deficient CD4+ T cells in vitro and in vivo. Mir155 was bound by Th17 cell transcription factors and was highly expressed during Th17 cell differentiation. miR-155-deficient Th17 and T regulatory (Treg) cells expressed increased amounts of Jarid2, a DNA-binding protein that recruits the Polycomb Repressive Complex 2 (PRC2) to chromatin. PRC2 binding to chromatin and H3K27 histone methylation was increased in miR-155-deficient cells, coinciding with failure to express Il22, Il10, Il9, and Atf3. Defects in Th17 cell cytokine expression and Treg cell homeostasis in the absence of Mir155 could be partially suppressed by Jarid2 deletion. Thus, miR-155 contributes to Th17 cell function by suppressing the inhibitory effects of Jarid2. |
2,716 | 223 | 23942116 | What is enCHIP? | Efficient isolation of specific genomic regions and identification of associated proteins by engineered DNA-binding molecule-mediated chromatin immunoprecipitation (enChIP) using CRISPR. Isolation of specific genomic regions retaining molecular interactions is necessary for their biochemical analysis. Here, we established a novel method, engineered DNA-binding molecule-mediated chromatin immunoprecipitation (enChIP), for purification of specific genomic regions retaining molecular interactions. We showed that enChIP using the CRISPR system efficiently isolates specific genomic regions. In this form of enChIP, specific genomic regions are immunoprecipitated with antibody against a tag(s), which is fused to a catalytically inactive form of Cas9 (dCas9), which is co-expressed with a guide RNA (gRNA) and recognizes endogenous DNA sequence in the genomic regions of interest. enChIP-mass spectrometry (enChIP-MS) targeting endogenous loci identified associated proteins. enChIP using the CRISPR system would be a convenient and useful tool for dissecting chromatin structure of genomic regions of interest. |
2,719 | 224 | 10364522 | How many genes does the human hoxD cluster contain? | Monodactylous limbs and abnormal genitalia are associated with hemizygosity for the human 2q31 region that includes the HOXD cluster. Vertebrates have four clusters of Hox genes (HoxA, HoxB, HoxC, and HoxD). A variety of expression and mutation studies indicate that posterior members of the HoxA and HoxD clusters play an important role in vertebrate limb development. In humans, mutations in HOXD13 have been associated with type II syndactyly or synpolydactyly, and, in HOXA13, with hand-foot-genital syndrome. We have investigated two unrelated children with a previously unreported pattern of severe developmental defects on the anterior-posterior (a-p) limb axis and in the genitalia, consisting of a single bone in the zeugopod, either monodactyly or oligodactyly in the autopod of all four limbs, and penoscrotal hypoplasia. Both children are heterozygous for a deletion that eliminates at least eight (HOXD3-HOXD13) of the nine genes in the HOXD cluster. We propose that the patients' phenotypes are due in part to haploinsufficiency for HOXD-cluster genes. This hypothesis is supported by the expression patterns of these genes in early vertebrate embryos. However, the involvement of additional genes in the region could explain the discordance, in severity, between these human phenotypes and the milder, non-polarized phenotypes present in mice hemizygous for HoxD cluster genes. These cases represent the first reported examples of deficiencies for an entire Hox cluster in vertebrates and suggest that the diploid dose of human HOXD genes is crucial for normal growth and patterning of the limbs along the anterior-posterior axis. |
2,721 | 225 | 3209676 | Is it safe to take isotretinoin during pregnancy? | Alterations in craniofacial growth induced by isotretinoin (13-cis-retinoic acid) in mouse whole embryo and primary mesenchymal cell culture. Recent evidence has demonstrated that 13-cis-retinoic acid (13-cis-RA, or isotretinoin) is responsible for various craniofacial malformations in the rodent and human embryo. Our studies have been directed toward understanding this effect using mouse whole embryo and primary cell cultures. In whole embryo culture, 13-cis-RA caused significant overall embryonic growth retardation, especially in the primary and secondary palatal processes. In embryos explanted on day 10 of gestation and exposed for 24 or 48 hr, the mesenchyme beneath the epithelium of the nasal and maxillary processes contained pyknotic nuclei as well as a dramatically reduced number of nuclei incorporating 3H-thymidine. The secondary palatal processes and the roof of the oral-nasal cavity had fewer mesenchymal cells than control embryos. The incorporation of 3H-thymidine into TCA-insoluble macromolecules was 30% less in the retinoid-treated heads. In primary cell cultures from day-12 mouse secondary palatal mesenchyme, subsequent cell growth was decreased at concentrations of 13-cis-RA greater than 1 X 10(-5) M. After a 40-hr treatment period, labeling indices in retinoid-treated cells were significantly lower than control values (25% compared with 40%). Retinoic acid also caused a significant, concentration-dependent decrease in 3H-thymidine incorporation. The inhibitory effect of 13-cis-RA on proliferation of oral-nasal mesenchymal cells appears to be related to the production of craniofacial malformations. |
2,743 | 226 | 22666487 | Which protein is the E3-ubiquitin ligase that targets the tumor suppressor p53 for proteasomal degradation? | Mdm2 RING mutation enhances p53 transcriptional activity and p53-p300 interaction. The p53 transcription factor and tumor suppressor is regulated primarily by the E3 ubiquitin ligase Mdm2, which ubiquitinates p53 to target it for proteasomal degradation. Aside from its ubiquitin ligase function, Mdm2 has been believed to be capable of suppressing p53's transcriptional activity by binding with and masking the transactivation domain of p53. The ability of Mdm2 to restrain p53 activity by binding alone, without ubiquitination, was challenged by a 2007 study using a knockin mouse harboring a single cysteine-to-alanine point mutation (C462A) in Mdm2's RING domain. Mouse embryonic fibroblasts with this mutation, which abrogates Mdm2's E3 ubiquitin ligase activity without affecting its ability to bind with p53, were unable to suppress p53 activity. In this study, we utilized the Mdm2(C462A) mouse model to characterize in further detail the role of Mdm2's RING domain in the control of p53. Here, we show in vivo that the Mdm2(C462A) protein not only fails to suppress p53, but compared to the complete absence of Mdm2, Mdm2(C462A) actually enhances p53 transcriptional activity toward p53 target genes p21/CDKN1A, MDM2, BAX, NOXA, and 14-3-3σ. In addition, we found that Mdm2(C462A) facilitates the interaction between p53 and the acetyltransferase CBP/p300, and it fails to heterodimerize with its homolog and sister regulator of p53, Mdmx, suggesting that a fully intact RING domain is required for Mdm2's inhibition of the p300-p53 interaction and for its interaction with Mdmx. These findings help us to better understand the complex regulation of the Mdm2-p53 pathway and have important implications for chemotherapeutic agents targeting Mdm2, as they suggest that inhibition of Mdm2's E3 ubiquitin ligase activity may be sufficient for increasing p53 activity in vivo, without the need to block Mdm2-p53 binding. |
2,759 | 227 | 23495154 | Can DNA intercalators function as topoisomerase inhibitors? | Structure-activity relationship of polypyridyl ruthenium(II) complexes as DNA intercalators, DNA photocleavage reagents, and DNA topoisomerase and RNA polymerase inhibitors. To investigate the relationship between the molecular structure and biological activity of polypyridyl Ru(II) complexes, such as DNA binding, photocleavage ability, and DNA topoisomerase and RNA polymerase inhibition, six new [Ru(bpy)(2)(dppz)](2+) (bpy=2,2'-bipyridine; dppz=dipyrido[3,2-a:2,',3'-c]phenazine) analogs have been synthesized and characterized by means of (1)H-NMR spectroscopy, mass spectrometry, and elemental analysis. Interestingly, the biological properties of these complexes have been identified to be quite different via a series of experimental methods, such as spectral titration, DNA thermal denaturation, viscosity, and gel electrophoresis. To explain the experimental regularity and reveal the underlying mechanism of biological activity, the properties of energy levels and population of frontier molecular orbitals and excited-state transitions of these complexes have been studied by density-functional theory (DFT) and time-depended DFT (TDDFT) calculations. The results suggest that DNA intercalative ligands with better planarity, greater hydrophobicity, and less steric hindrance are beneficial to the DNA intercalation and enzymatic inhibition of their complexes. |
2,793 | 228 | 22659469 | Which diseases is microRNA 132 (miR-132) implicated in? | Role of miR-132 in angiogenesis after ocular infection with herpes simplex virus. MicroRNAs (miRNAs) are small regulatory molecules that control diverse biological processes that include angiogenesis. Herpes simplex virus (HSV) causes a chronic immuno-inflammatory response in the eye that may result in corneal neovascularization during blinding immunopathological lesion stromal keratitis (SK). miR-132 is a highly conserved miRNA that is induced in endothelial cells in response to growth factors, such as vascular endothelial growth factor (VEGF). In this study, we show that miR-132 expression was up-regulated (10- to 20-fold) after ocular infection with HSV, an event that involved the production of both VEGF-A and IL-17. Consequently, blockade of VEGF-A activity using soluble VEGF receptor 1 resulted in significantly lower levels of corneal miR-132 after HSV infection. In addition, low levels of corneal miR-132 were detected in IL-17 receptor knockout mice after HSV infection. In vivo silencing of miR-132 by the provision of anti-miR-132 (antagomir-132) nanoparticles to HSV-infected mice led to reduced corneal neovascularization and diminished SK lesions. The anti-angiogenic effect of antagomir-132 was reflected by a reduction in angiogenic Ras activity in corneal CD31-enriched cells (presumably blood vessel endothelial cells) during SK. To our knowledge, this is one of the first reports of miRNA involvement in an infectious ocular disease. Manipulating miRNA expression holds promise as a therapeutic approach to control an ocular lesion that is an important cause of human blindness. |
2,805 | 229 | 23313319 | Which are the human glutamate transporters? | Astrocyte GRK2 as a novel regulator of glutamate transport and brain damage. G protein-coupled receptor (GPCR) kinase 2 (GRK2) regulates cellular signaling via desensitization of GPCRs and by direct interaction with intracellular signaling molecules. We recently described that ischemic brain injury decreases cerebral GRK2 levels. Here we studied the effect of astrocyte GRK2-deficiency on neonatal brain damage in vivo. As astrocytes protect neurons by taking up glutamate via plasma-membrane transporters, we also studied the effect of GRK2 on the localization of the GLutamate ASpartate Transporter (GLAST). Brain damage induced by hypoxia-ischemia was significantly reduced in GFAP-GRK2(+/-) mice, which have a 60% reduction in astrocyte GRK2 compared to GFAP-WT littermates. In addition, GRK2-deficient astrocytes have higher plasma-membrane levels of GLAST and an increased capacity to take up glutamate in vitro. In search for the mechanism by which GRK2 regulates GLAST expression, we observed increased GFAP levels in GRK2-deficient astrocytes. GFAP and the cytoskeletal protein ezrin are known regulators of GLAST localization. In line with this evidence, GRK2-deficiency reduced phosphorylation of the GRK2 substrate ezrin and enforced plasma-membrane GLAST association after stimulation with the group I mGluR-agonist DHPG. When ezrin was silenced, the enhanced plasma-membrane GLAST association in DHPG-exposed GRK2-deficient astrocytes was prevented. In conclusion, we identified a novel role of astrocyte GRK2 in regulating plasma-membrane GLAST localization via an ezrin-dependent route. We demonstrate that the 60% reduction in astrocyte GRK2 protein level that is observed in GFAP-GRK2(+/-) mice is sufficient to significantly reduce neonatal ischemic brain damage. These findings underline the critical role of GRK2 regulation in astrocytes for dampening the extent of brain damage after ischemia. |
2,823 | 230 | 18690037 | What are the functions of sorting nexin 27? | Subunit-specific regulation of Kir3 channels by sorting nexin 27. G protein-gated inwardly rectifying potassium (Kir3) channels are involved in regulating membrane excitability in the brain. Kir3 channels have been shown to play a role in learning, analgesia and drug addiction. Little is known about the cell surface regulation of Kir3 channels. Using a proteomics approach, we recently discovered that sorting nexin 27 (SNX27) associates with a subset of Kir3 channels. Sorting nexins have been implicated in trafficking of proteins through endosomal compartments. The single PDZ domain of SNX27 binds directly to the PDZ binding motif of Kir3 channels leading to their downregulation. Here, we examined the functional effect of SNX27b expression on different subunit combinations of the Kir3 family. Our results show that regulation of Kir3 channels by SNX27 depends critically on the combination of Kir3 subunits. This type of subunit-specific regulation could be important for determining the extent of Kir3 inhibition in normal as well as diseased states, such as drug addiction. |
2,837 | 231 | 25242375 | Do orphan and gene related CpG islands follow power-law-like distributions? | Orphan and gene related CpG Islands follow power-law-like distributions in several genomes: evidence of function-related and taxonomy-related modes of distribution. CpG Islands (CGIs) are compositionally defined short genomic stretches, which have been studied in the human, mouse, chicken and later in several other genomes. Initially, they were assigned the role of transcriptional regulation of protein-coding genes, especially the house-keeping ones, while more recently there is found evidence that they are involved in several other functions as well, which might include regulation of the expression of RNA genes, DNA replication etc. Here, an investigation of their distributional characteristics in a variety of genomes is undertaken for both whole CGI populations as well as for CGI subsets that lie away from known genes (gene-unrelated or "orphan" CGIs). In both cases power-law-like linearity in double logarithmic scale is found. An evolutionary model, initially put forward for the explanation of a similar pattern found in gene populations is implemented. It includes segmental duplication events and eliminations of most of the duplicated CGIs, while a moderate rate of non-duplicated CGI eliminations is also applied in some cases. Simulations reproduce all the main features of the observed inter-CGI chromosomal size distributions. Our results on power-law-like linearity found in orphan CGI populations suggest that the observed distributional pattern is independent of the analogous pattern that protein coding segments were reported to follow. The power-law-like patterns in the genomic distributions of CGIs described herein are found to be compatible with several other features of the composition, abundance or functional role of CGIs reported in the current literature across several genomes, on the basis of the proposed evolutionary model. |
2,838 | 232 | 11125105 | What is the proportion of non canonical splice sites in the human genome? | SpliceDB: database of canonical and non-canonical mammalian splice sites. A database (SpliceDB) of known mammalian splice site sequences has been developed. We extracted 43 337 splice pairs from mammalian divisions of the gene-centered Infogene database, including sites from incomplete or alternatively spliced genes. Known EST sequences supported 22 815 of them. After discarding sequences with putative errors and ambiguous location of splice junctions the verified dataset includes 22 489 entries. Of these, 98.71% contain canonical GT-AG junctions (22 199 entries) and 0.56% have non-canonical GC-AG splice site pairs. The remainder (0.73%) occurs in a lot of small groups (with a maximum size of 0.05%). We especially studied non-canonical splice sites, which comprise 3.73% of GenBank annotated splice pairs. EST alignments allowed us to verify only the exonic part of splice sites. To check the conservative dinucleotides we compared sequences of human non-canonical splice sites with sequences from the high throughput genome sequencing project (HTG). Out of 171 human non-canonical and EST-supported splice pairs, 156 (91.23%) had a clear match in the human HTG. They can be classified after sequence analysis as: 79 GC-AG pairs (of which one was an error that corrected to GC-AG), 61 errors corrected to GT-AG canonical pairs, six AT-AC pairs (of which two were errors corrected to AT-AC), one case was produced from a non-existent intron, seven cases were found in HTG that were deposited to GenBank and finally there were only two other cases left of supported non-canonical splice pairs. The information about verified splice site sequences for canonical and non-canonical sites is presented in SpliceDB with the supporting evidence. We also built weight matrices for the major splice groups, which can be incorporated into gene prediction programs. SpliceDB is available at the computational genomic Web server of the Sanger Centre: http://genomic.sanger.ac. uk/spldb/SpliceDB.html and at http://www.softberry. com/spldb/SpliceDB.html. |
2,840 | 233 | 24043422 | List protein gel staining methods visualizing the entire protein set. | Coomassie blue as a near-infrared fluorescent stain: a systematic comparison with Sypro Ruby for in-gel protein detection. Quantitative proteome analyses suggest that the well-established stain colloidal Coomassie Blue, when used as an infrared dye, may provide sensitive, post-electrophoretic in-gel protein detection that can rival even Sypro Ruby. Considering the central role of two-dimensional gel electrophoresis in top-down proteomic analyses, a more cost effective alternative such as Coomassie Blue could prove an important tool in ongoing refinements of this important analytical technique. To date, no systematic characterization of Coomassie Blue infrared fluorescence detection relative to detection with SR has been reported. Here, seven commercial Coomassie stain reagents and seven stain formulations described in the literature were systematically compared. The selectivity, threshold sensitivity, inter-protein variability, and linear-dynamic range of Coomassie Blue infrared fluorescence detection were assessed in parallel with Sypro Ruby. Notably, several of the Coomassie stain formulations provided infrared fluorescence detection sensitivity to <1 ng of protein in-gel, slightly exceeding the performance of Sypro Ruby. The linear dynamic range of Coomassie Blue infrared fluorescence detection was found to significantly exceed that of Sypro Ruby. However, in two-dimensional gel analyses, because of a blunted fluorescence response, Sypro Ruby was able to detect a few additional protein spots, amounting to 0.6% of the detected proteome. Thus, although both detection methods have their advantages and disadvantages, differences between the two appear to be small. Coomassie Blue infrared fluorescence detection is thus a viable alternative for gel-based proteomics, offering detection comparable to Sypro Ruby, and more reliable quantitative assessments, but at a fraction of the cost. |
2,851 | 234 | 18708826 | What clinical use aptamers may have? | Investigational antiplatelet drugs for the treatment and prevention of coronary artery disease. Antiplatelet therapy for the prevention and treatment of coronary artery disease (CAD) has undergone dramatic changes and improvements. Aspirin remains the first-line antiplatelet drug for clinical use. Newer platelet inhibitors such as the thienopyridine agents, ticlopidine and clopidogrel, have also been shown to be effective in treating CAD. There have been ongoing efforts to evaluate newer antiplatelet drugs, with the potential to improve clinical efficacy and safety. Some of the more promising antiplatelet agents include new adenosine diphosphate receptor antagonists such as prasugrel, cangrelor, and ticagrelor (AZD6140). In addition, a new thromboxane receptor antagonist, NCX-4016, a newly discovered protease-activated receptor antagonist that targets thrombin-induced platelet aggregation, and anti-von Willebrand factor aptamers show tremendous promise in refining antiplatelet therapy by targeting different receptors and molecules. |
2,868 | 235 | 24304681 | What is the causative agent of the "Panama disease" affecting bananas? | Analysis of banana transcriptome and global gene expression profiles in banana roots in response to infection by race 1 and tropical race 4 of Fusarium oxysporum f. sp. cubense. BACKGROUND: Cavendish, the most widely grown banana cultivar, is relatively resistant to Race 1 of Fusarium oxysporum f. sp. cubense (Foc1) which caused widespread Panama disease during the first half of the 20th century but is susceptible to Tropical Race 4 of Foc (Foc TR4) which is threatening world banana production. The genome of the diploid species Musa acuminata which is the ancestor of a majority of triploid banana cultivars has recently been sequenced. Availability of banana transcriptomes will be highly useful for improving banana genome annotation and for biological research. The knowledge of global gene expression patterns influenced by infection of different Foc races will help to understand the host responses to the infection. RESULTS: RNA samples from different organs of the Cavendish cultivar were pooled for deep sequencing using the Illumina technology. Analysis of the banana transcriptome led to identification of over 842 genes that were not annotated by the Musa genome project. A large number of simple nucleotide polymorphisms (SNPs) and short insertions and deletion (indels) were identified from the transcriptome data. GFP-expressing Foc1 and Foc TR4 were used to monitor the infection process. Both Foc1 and Foc TR4 were found to be able to invade banana roots and spread to root vascular tissues in the first two days following inoculation. Digital gene expression (DGE) profiling analysis reveal that the infection by Foc1 and Foc TR4 caused very similar changes in the global gene expression profiles in the banana roots during the first two days of infection. The Foc infection led to induction of many well-known defense-related genes. Two genes encoding the ethylene biosynthetic enzyme ACC oxidase and several ethylene-responsive transcription factors (ERF) were among the strongly induced genes by both Foc1 and Foc TR4. CONCLUSIONS: Both Foc1 and Foc TR4 are able to spread into the vascular system of banana roots during the early infection process and their infection led to similar gene expression profiles in banana roots. The transcriptome profiling analysis indicates that the ethylene synthetic and signalling pathways were activated in response to the Foc infection. |
2,875 | 236 | 22078567 | What is the mechanism of action of Nalmefene? | Structural basis for μ-opioid receptor binding and activation. Opioids that stimulate the μ-opioid receptor (MOR1) are the most frequently prescribed and effective analgesics. Here we present a structural model of MOR1. Molecular dynamics simulations show a ligand-dependent increase in the conformational flexibility of the third intracellular loop that couples with the G protein complex. These simulations likewise identified residues that form frequent contacts with ligands. We validated the binding residues using site-directed mutagenesis coupled with radioligand binding and functional assays. The model was used to blindly screen a library of ∼1.2 million compounds. From the 34 compounds predicted to be strong binders, the top three candidates were examined using biochemical assays. One compound showed high efficacy and potency. Post hoc testing revealed this compound to be nalmefene, a potent clinically used antagonist, thus further validating the model. In summary, the MOR1 model provides a tool for elucidating the structural mechanism of ligand-initiated cell signaling and for screening novel analgesics. |
2,878 | 237 | 20048621 | Synostosis of which cranial structures are characteristic to the Mercedes Benz syndrome? | Mercedes Benz pattern craniosynostosis. BACKGROUND: The complex craniosynostoses, which include all nonsyndromic multiple sutural fusions, represent a small fraction of patients presenting with craniosynostosis. Among these are a trisutural fusion, dubbed the "Mercedes Benz pattern," involving the sagittal and both lambdoid sutures. The purpose of this report is to review the authors' series of this unusual form of craniosynostosis, to identify associated anomalies, and to assess treatment outcomes. METHODS: The authors conducted a retrospective clinical outcome assessment of all patients presenting with Mercedes Benz pattern craniosynostosis. Growth was assessed by direct anthropologic measurements, and significance was assessed by the t test. RESULTS: Over a 17-year period, 11 of 802 patients presenting with craniosynostosis were identified with Mercedes Benz pattern synostosis (1.4 percent). Three patients had additional sutural involvement and two had identifiable genetic syndromes. Seven of 11 (64 percent) had cerebellar tonsillar herniation on preoperative imaging, and four symptomatic patients (36 percent) have required Chiari decompressions. Three patients have required more than one remodeling procedure. Serial postoperative anthropologic measurements identified progressive brachycephaly, with diminished growth in both head circumference and skull length (mean follow-up, 3.75 years). Cognitive function was grossly normal, except for one syndromic patient. CONCLUSIONS: Despite fusion of the sagittal suture, the surgical treatment for Mercedes Benz pattern craniosynostosis should include skull lengthening, not reduction. The authors' findings for diminished postoperative growth suggest that an overcorrection be considered. Fourth or fifth sutural involvement correlated with additional corrections. Given the observed high incidence for symptomatic cerebellar tonsillar herniation, routine magnetic resonance evaluations are recommended for affected individuals. |
2,881 | 238 | 24105977 | Can valproic acid act as an activator of AMPK? | Valproic acid is a novel activator of AMP-activated protein kinase and decreases liver mass, hepatic fat accumulation, and serum glucose in obese mice. Valproic acid (VPA) is a widely prescribed anticonvulsant for the treatment of epilepsy. Here we demonstrate that VPA is a novel activator of AMP-activated protein kinase (AMPK), a key regulator of cellular metabolism, using primary mouse and human hepatocytes. Incubation of primary mouse hepatocytes with VPA resulted in increased levels of phosphorylated AMPK and acetyl-CoA carboxylase (ACC). This finding was recapitulated using primary human hepatocytes. Pretreatment of mouse hepatocytes with a small-molecule inhibitor of AMPK, Compound C (6-[4-(2-piperidin-1-ylethoxy)phenyl]-3-pyridin-4-ylpyrazolo[1,5-a]pyrimidine), abrogated the phosphorylation of ACC following treatment with VPA. The cytochrome P450 inhibitor 1-aminobenzotriazole blocked the VPA-stimulated phosphorylation of AMPK, suggesting a requirement for biotransformation of VPA. In line with this, treatment of hepatocytes with metabolites of VPA resulted in increased phosphorylation of AMPK/ACC as compared with VPA. Treatment of ob/ob mice with VPA for 14 days resulted in decreased liver masses, hepatic fat accumulation, and serum glucose. These results paralleled those observed in mice treated with metformin. In addition, a targeted mass spectrometry-based metabolomics assay revealed several small molecules that were differentially abundant in the serum of ob/ob mice treated with VPA as compared with vehicle-treated mice. These studies are the first to establish VPA and its metabolites as in vitro activators of AMPK. |
2,883 | 239 | 21679342 | Which signaling pathways have been associated with medulloblastoma formation and growth? | Hedgehog signaling pathway as a therapeutic target in various types of cancer. Hedgehog (Hh) signaling is an important factor in growth and patterning during embryonic development. A mutation in Patched, Smoothened or Gli1, which regulate the Hh signaling pathway, might lead to the onset of glioblastoma, basal cell carcinoma, medulloblastoma and rhabdomyosarcoma. Recently, Hh signaling has been reported to be activated in a ligand-dependent manner, contributing to carcinogenesis and cancer progression. Hedgehog signaling is reactivated in various types of cancer, and this contributes to cancer progression by facilitating proliferation, invasion and cell survival. Moreover, Hh signaling is associated with several other signaling pathways that contribute to cancer progression. These observations indicate that controlling Hh signaling might become a target for novel molecular targeting therapy. |
2,899 | 240 | 23873099 | What is the role of invadopodia in EMT? | Twist: a molecular target in cancer therapeutics. Twist, the basic helix-loop-helix transcription factor, is involved in the process of epithelial to mesenchymal transitions (EMTs), which play an essential role in cancer metastasis. Overexpression of Twist or its promoter methylation is a common scenario in metastatic carcinomas. Twist is activated by a variety of signal transduction pathways, including Akt, signal transducer and activator of transcription 3, mitogen-activated protein kinase, Ras, and Wnt signaling. Activated Twist upregulates N-cadherin and downregulates E-cadherin, which are the hallmarks of EMT. Moreover, Twist plays an important role in some physiological processes involved in metastasis, like angiogenesis, invadopodia, extravasation, and chromosomal instability. Twist also protects cancer cells from apoptotic cell death. In addition, Twist is responsible for the stemness of cancer cells and the generation of drug resistance. Recently, targeting Twist has gained significant interests in cancer therapeutics. The inactivation of Twist by small RNA technology or chemotherapeutic approach has been proved successful. Moreover, several inhibitors which are antagonistic to the upstream or downstream molecules of Twist signaling pathways have also been identified. Development of potential treatment strategies by targeting Twist has a great promise in cancer therapeutics. |
2,907 | 241 | 23416983 | What are cancer driver genes? | Cancer driver-passenger distinction via sporadic human and dog cancer comparison: a proof-of-principle study with colorectal cancer. Herein we report a proof-of-principle study illustrating a novel dog-human comparison strategy that addresses a central aim of cancer research, namely cancer driver-passenger distinction. We previously demonstrated that sporadic canine colorectal cancers (CRCs) share similar molecular pathogenesis mechanisms as their human counterparts. In this study, we compared the genome-wide copy number abnormalities between 29 human and 10 canine sporadic CRCs. This led to the identification of 73 driver candidate genes (DCGs), altered in both species, and with 27 from the whole genome and 46 from dog-human genomic rearrangement breakpoint (GRB) regions, as well as 38 passenger candidate genes (PCGs), altered in humans only and located in GRB regions. We noted that DCGs significantly differ from PCGs in every analysis conducted to assess their cancer relevance and biological functions. Importantly, although PCGs are not enriched in any specific functions, DCGs possess significantly enhanced functionality closely associated with cell proliferation and death regulation, as well as with epithelial cell apicobasal polarity establishment/maintenance. These observations support the notion that, in sporadic CRCs of both species, cell polarity genes not only contribute in preventing cancer cell invasion and spreading, but also likely serve as tumor suppressors by modulating cell growth. This pilot study validates our novel strategy and has uncovered four new potential cell polarity and colorectal tumor suppressor genes (RASA3, NUPL1, DENND5A and AVL9). Expansion of this study would make more driver-passenger distinctions for cancers with large genomic amplifications or deletions, and address key questions regarding the relationship between cancer pathogenesis and epithelial cell polarity control in mammals. |
2,919 | 242 | 23637282 | What is a mitochondrial nucleoid? | The mitochondrial nucleoid: integrating mitochondrial DNA into cellular homeostasis. The packaging of mitochondrial DNA (mtDNA) into DNA-protein assemblies called nucleoids provides an efficient segregating unit of mtDNA, coordinating mtDNA's involvement in cellular metabolism. From the early discovery of mtDNA as "extranuclear" genetic material, its organization into nucleoids and integration into both the mitochondrial organellar network and the cell at large via a variety of signal transduction pathways, mtDNA is a crucial component of the cell's homeostatic network. The mitochondrial nucleoid is composed of a set of DNA-binding core proteins involved in mtDNA maintenance and transcription, and a range of peripheral factors, which are components of signaling pathways controlling mitochondrial biogenesis, metabolism, apoptosis, and retrograde mitochondria-to-nucleus signaling. The molecular interactions of nucleoid components with the organellar network and cellular signaling pathways provide exciting clues to the dynamic integration of mtDNA into cellular metabolic homeostasis. |
2,926 | 243 | 22130792 | What is the treatment of amiodarone-induced thyrotoxicosis? | Treatment of amiodarone-induced thyrotoxicosis type 2: a randomized clinical trial. CONTEXT: Amiodarone-induced thyrotoxicosis (AIT) type 2 is self-limiting in nature, but most physicians are reluctant to continue amiodarone. When prednisone fails to restore euthyroidism, possibly due to mixed cases of AIT type 1 and 2, perchlorate (ClO(4)) might be useful because ClO(4) reduces the cytotoxic effect of amiodarone on thyrocytes. OBJECTIVES: Our objectives were to demonstrate the feasibility of continuation of amiodarone in AIT type 2 and to evaluate the usefulness of ClO(4) (given alone or in combination with prednisone) in AIT type 2. DESIGN AND SETTING: A randomized multicenter study was conducted in 10 Dutch hospitals. METHODS: Patients with AIT type 2 were randomized to receive prednisone 30 mg/d (group A, n = 12), sodium perchlorate 500 mg twice daily (group B, n = 14), or prednisone plus perchlorate (group C, n = 10); all patients continued amiodarone and were also treated with methimazole 30 mg/d. Follow-up was 2 yr. MAIN OUTCOME MEASURES: Treatment efficacy (defined as TSH values ≥ 0.4 mU/liter under continuation of amiodarone) and recurrent thyrotoxicosis were evaluated. RESULTS: Initial therapy was efficacious in 100, 71, and 100% of groups A, B, and C, respectively (P = 0.03). The 29% failures in group B became euthyroid after addition of prednisone. Neither the time to reach TSH of 0.4 mU/liter or higher [8 wk (4-20), 14 wk (4-32), and 12 wk (4-28) in groups A, B, and C respectively] nor the time to reach free T(4) of 25 pmol/liter or below [4 wk (4-20), 12 wk (4-20), and 8 wk (4-20) in groups A, B, and C) were significantly different between groups (values as median with range). Recurrent thyrotoxicosis occurred in 8.3%. CONCLUSION: Euthyroidism was reached despite continuation of amiodarone in all patients. Prednisone remains the preferred treatment modality of AIT type 2, because perchlorate given alone or in combination with prednisone had no better outcomes. |
2,939 | 244 | 11577024 | How does exercise affect thyroid hormone receptors expression in the heart? | Regulation of thyroid hormone receptor isoforms in physiological and pathological cardiac hypertrophy. Physiological and pathological cardiac hypertrophy have directionally opposite changes in transcription of thyroid hormone (TH)-responsive genes, including alpha- and beta-myosin heavy chain (MyHC) and sarcoplasmic reticulum Ca(2+)-ATPase (SERCA), and TH treatment can reverse molecular and functional abnormalities in pathological hypertrophy, such as pressure overload. These findings suggest relative hypothyroidism in pathological hypertrophy, but serum levels of TH are usually normal. We studied the regulation of TH receptors (TRs) beta1, alpha1, and alpha2 in pathological and physiological rat cardiac hypertrophy models with hypothyroid- and hyperthyroid-like changes in the TH target genes, alpha- and beta-MyHC and SERCA. All 3 TR subtypes in myocytes were downregulated in 2 hypertrophy models with a hypothyroid-like mRNA phenotype, phenylephrine in culture and pressure overload in vivo. Myocyte TRbeta1 was upregulated in models with a hyperthyroid-like phenotype, TH (triiodothyronine, T3), in culture and exercise in vivo. In myocyte culture, TR overexpression, or excess T3, reversed the effects of phenylephrine on TH-responsive mRNAs and promoters. In addition, TR cotransfection and treatment with the TRbeta1-selective agonist GC-1 suggested different functional coupling of the TR isoforms, TRbeta1 to transcription of beta-MyHC, SERCA, and TRbeta1, and TRalpha1 to alpha-MyHC transcription and increased myocyte size. We conclude that TR isoforms have distinct regulation and function in rat cardiac myocytes. Changes in myocyte TR levels can explain in part the characteristic molecular phenotypes in physiological and pathological cardiac hypertrophy. |
2,942 | 245 | 22984601 | Is the Drosophila Translational Control Element (TCE) involved in spermatogenesis? | The Drosophila Translational Control Element (TCE) is required for high-level transcription of many genes that are specifically expressed in testes. To investigate the importance of core promoter elements for tissue-specific transcription of RNA polymerase II genes, we examined testis-specific transcription in Drosophila melanogaster. Bioinformatic analyses of core promoter sequences from 190 genes that are specifically expressed in testes identified a 10 bp A/T-rich motif that is identical to the translational control element (TCE). The TCE functions in the 5' untranslated region of Mst(3)CGP mRNAs to repress translation, and it also functions in a heterologous gene to regulate transcription. We found that among genes with focused initiation patterns, the TCE is significantly enriched in core promoters of genes that are specifically expressed in testes but not in core promoters of genes that are specifically expressed in other tissues. The TCE is variably located in core promoters and is conserved in melanogaster subgroup species, but conservation dramatically drops in more distant species. In transgenic flies, short (300-400 bp) genomic regions containing a TCE directed testis-specific transcription of a reporter gene. Mutation of the TCE significantly reduced but did not abolish reporter gene transcription indicating that the TCE is important but not essential for transcription activation. Finally, mutation of testis-specific TFIID (tTFIID) subunits significantly reduced the transcription of a subset of endogenous TCE-containing but not TCE-lacking genes, suggesting that tTFIID activity is limited to TCE-containing genes but that tTFIID is not an obligatory regulator of TCE-containing genes. Thus, the TCE is a core promoter element in a subset of genes that are specifically expressed in testes. Furthermore, the TCE regulates transcription in the context of short genomic regions, from variable locations in the core promoter, and both dependently and independently of tTFIID. These findings set the stage for determining the mechanism by which the TCE regulates testis-specific transcription and understanding the dual role of the TCE in translational and transcriptional regulation. |
2,944 | 246 | 12719670 | What are the symptoms of abacavir hypersensitivity? | Enanthema as the first clinical manifestation of abacavir hypersensitivity reaction: a case report. Abacavir is a nucleoside analogue reverse transcriptase inhibitor used in combination with other antiretroviral drugs for the treatment of HIV 1-infection. Approximately 3% of patients who receive abacavir develop an idiosyncratic hypersensitivity reaction. The most common symptoms are fever, skin rash and gastrointestinal disorders. Respiratory symptoms occurred in approximately 20% of patients who have hypersensitivity reaction. We describe the first case, to our knowledge, of hypesensitivity reaction characterized by enanthema and fever without skin rash promptly resolved after discontinuation of abacavir |
2,948 | 247 | 22833515 | What is the effect of ivabradine in heart failure with preserved ejection fraction? | Heart rate reduction by If-inhibition improves vascular stiffness and left ventricular systolic and diastolic function in a mouse model of heart failure with preserved ejection fraction. AIMS: In diabetes mellitus, heart failure with preserved ejection fraction (HFPEF) is a significant comorbidity. No therapy is available that improves cardiovascular outcomes. The aim of this study was to characterize myocardial function and ventricular-arterial coupling in a mouse model of diabetes and to analyse the effect of selective heart rate (HR) reduction by If-inhibition in this HFPEF-model. METHODS AND RESULTS: Control mice, diabetic mice (db/db), and db/db mice treated for 4 weeks with the If-inhibitor ivabradine (db/db-Iva) were compared. Aortic distensibility was measured by magnetic resonance imaging. Left ventricular (LV) pressure-volume analysis was performed in isolated working hearts, with biochemical and histological characterization of the cardiac and aortic phenotype. In db/db aortic stiffness and fibrosis were significantly enhanced compared with controls and were prevented by HR reduction in db/db-Iva. Left ventricular end-systolic elastance (Ees) was increased in db/db compared with controls (6.0 ± 1.3 vs. 3.4 ± 1.2 mmHg/µL, P < 0.01), whereas other contractility markers were reduced. Heart rate reduction in db/db-Iva lowered Ees (4.0 ± 1.1 mmHg/µL, P < 0.01), and improved the other contractility parameters. In db/db active relaxation was prolonged and end-diastolic capacitance was lower compared with controls (28 ± 3 vs. 48 ± 8 μL, P < 0.01). These parameters were ameliorated by HR reduction. Neither myocardial fibrosis nor hypertrophy were detected in db/db, whereas titin N2B expression was increased and phosphorylation of phospholamban was reduced both being prevented by HR reduction in db/db-Iva. CONCLUSION: In db/db, a model of HFPEF, selective HR reduction by If-inhibition improved vascular stiffness, LV contractility, and diastolic function. Therefore, If-inhibition might be a therapeutic concept for HFPEF, if confirmed in humans. |
2,953 | 248 | 958900 | Is low T3 syndrome a prognostic marker in patients with renal insufficiency? | [Thyroid hormones and thyrotropin in liver and kidney insufficiency]. In 22 patients with hepatic or renal insufficiency the serum concentrations of trijodothyronin, thyroxine and thyrotropin and also the T4-binding capacity of TBG were determined. The mean serum T3 concentration was found to be significantly lower in patients with hepatic coma when compared with euthyroid subjects. In the cases of renal insufficiency the serum T3 concentrations were in the normal range. Due to hormone loss through dialysis however, the mean value of the T3 concentrations was slightly lower than the average concentration of normal subjects. The obtained results agree with those of our earlier studies which showed that there are significant differences between liver artery and vein T3 concentrations in serum, whereas no such differences could be ascertained between serum concentrations in renal artery and vein. On the basis of these findings it is assumed that conversion of T4 into T3 occurs predominantly in the liver. |
2,969 | 249 | 8725589 | Does burning mouth syndrome preferentially affect post-mepopausal women? | Burning mouth syndrome. Burning mouth syndrome is a common condition particularly affecting elderly women. Numerous precipitating factors are recognized that lead to a burning sensation in clinically normal mucosa. By taking each precipitating factor into account, a favorable treatment outcome usually can be achieved. This article highlights the significance of precipitating factors in burning mouth syndrome and suggests a treatment protocol based on current scientific evidence. |
3,025 | 250 | 12783138 | Which biomarker is widely used in the diagnosis of Ewing sarcoma? | Primary cutaneous pre-B lymphoblastic lymphoma immunohistologically mimics Ewing's sarcoma/primitive neuroectodermal tumor. Precursor B-cell lymphoblastic lymphomas (B-LBLs) are rare and most often involve the skin in the head and neck region. Histologically, cutaneous B-LBLs may be confused with other small round-cell neoplasms. Moreover, half of B-LBL patients are negative for CD45 (leucocyte common antigen, LCA), a widely used marker for the diagnosis of lymphoma, and a significant portion express CD99, a marker for Ewing's sarcoma (ES) or primitive neuroectodermal tumor (PNET). Therefore, an extranodal B-LBL may be misinterpreted as PNET or ES. Here, we report on 2 boys, aged 10 and 5 years, with primary cutaneous B-LBL of the scalp. PNET was initially misdiagnosed because the tumor cells were negative for CD45 but strongly positive for CD99. Advanced stage of acute lymphoblastic leukemia (ALL) developed later and both patients died during the course of treatment for ALL. In retrospective analyses, tumor cells in the initial biopsy specimens of both patients were found to be reactive to terminal deoxynucleotidyl transferase (TdT), CD43 and CD10. Thus, the diagnosis of B-LBL was confirmed. These cases illustrate the possibility that primary cutaneous B-LBL may mimic ES or PNET immunophenotypically, and that correct diagnosis in doubtful cases may be facilitated by analysis using a complete panel of antibodies, particularly including TdT and CD43. |
3,026 | 251 | 19416831 | Proteomic analyses have revealed proteins associated with the triple-negative breast cancers. List some proposed proteins. | Hsp90 inhibitor PU-H71, a multimodal inhibitor of malignancy, induces complete responses in triple-negative breast cancer models. Triple-negative breast cancers (TNBCs) are defined by a lack of expression of estrogen, progesterone, and HER2 receptors. Because of the absence of identified targets and targeted therapies, and due to a heterogeneous molecular presentation, treatment guidelines for patients with TNBC include only conventional chemotherapy. Such treatment, while effective for some, leaves others with high rates of early relapse and is not curative for any patient with metastatic disease. Here, we demonstrate that these tumors are sensitive to the heat shock protein 90 (Hsp90) inhibitor PU-H71. Potent and durable anti-tumor effects in TNBC xenografts, including complete response and tumor regression, without toxicity to the host are achieved with this agent. Notably, TNBC tumors respond to retreatment with PU-H71 for several cycles extending for over 5 months without evidence of resistance or toxicity. Through a proteomics approach, we show that multiple oncoproteins involved in tumor proliferation, survival, and invasive potential are in complex with PU-H71-bound Hsp90 in TNBC. PU-H71 induces efficient and sustained downregulation and inactivation, both in vitro and in vivo, of these proteins. Among them, we identify downregulation of components of the Ras/Raf/MAPK pathway and G(2)-M phase to contribute to its anti-proliferative effect, degradation of activated Akt and Bcl-xL to induce apoptosis, and inhibition of activated NF-kappaB, Akt, ERK2, Tyk2, and PKC to reduce TNBC invasive potential. The results identify Hsp90 as a critical and multimodal target in this most difficult to treat breast cancer subtype and support the use of the Hsp90 inhibitor PU-H71 for clinical trials involving patients with TNBC. |
3,037 | 252 | 20457704 | Which signalling pathway is involved in Tuberous Sclerosis? | Sirolimus and tuberous sclerosis-associated renal angiomyolipomas. Tuberous sclerosis, caused by germline mutations in the TSC1 or TSC2 genes, is associated with aberrant upregulation of the mammalian target of rapamycin (mTOR) signalling pathway, resulting in growth of tumours, including renal angiomyolipomas (AMLs). AMLs may cause hypertension, renal failure and spontaneous life-threatening haemorrhage. Previously, invasive interventions were required to treat AMLs. More recently, mTOR inhibitors have been used as molecularly targeted treatment to treat AMLs. We present here the case of a paediatric patient with TSC in whom sirolimus has been used successfully to halt growth of renal AMLs. |
3,048 | 253 | 21150342 | Can life style changes reduce oxidative stress | Pericytopathy: oxidative stress and impaired cellular longevity in the pancreas and skeletal muscle in metabolic syndrome and type 2 diabetes. The pericyte's role has been extensively studied in retinal tissues of diabetic retinopathy; however, little is known regarding its role in such tissues as the pancreas and skeletal muscle. This supportive microvascular mural cell, plays an important and novel role in cellular and extracellular matrix remodeling in the pancreas and skeletal muscle of young rodent models representing the metabolic syndrome and type 2 diabetes mellitus (T2DM). Transmission electron microscopy can be used to evaluate these tissues from young rodent models of insulin resistance and T2DM, including the transgenic Ren2 rat, db/db obese insulin resistant - T2DM mouse, and human islet amyloid polypeptide (HIP) rat model of T2DM. With this method, the earliest pancreatic remodeling change was widening of the islet exocrine interface and pericyte hypercellularity, followed by pericyte differentiation into islet and pancreatic stellate cells with early fibrosis involving the islet exocrine interface and interlobular interstitium. In skeletal muscle there was a unique endothelial capillary connectivity via elongated longitudinal pericyte processes in addition to pericyte to pericyte and pericyte to myocyte cell-cell connections allowing for paracrine communication. Initial pericyte activation due to moderate oxidative stress signaling may be followed by hyperplasia, migration, and differentiation into adult mesenchymal cells. Continued robust oxidative stress may induce pericyte apoptosis and impaired cellular longevity. Circulating antipericyte autoantibodies have recently been characterized, and may provide a screening method to detect those patients who are developing pericyte loss and are at greater risk for the development of complications of T2DM due to pericytopathy and rarefaction. Once detected, these patients may be offered more aggressive treatment strategies such as early pharmacotherapy in addition to life style changes targeted to maintaining pericyte integrity. In conclusion, we have provided a review of current knowledge regarding the pericyte and novel ultrastructural findings regarding its role in metabolic syndrome and T2DM. |
3,052 | 254 | 2703281 | Which is the relation between sweating and anaerobic threshold? | Effect of active warming-up on thermoregulatory, circulatory, and metabolic responses to incremental exercise in endurance-trained athletes. The influence of 10 min warming-up at 40% VO2 max on thermal, circulatory, and metabolic responses to an incremental exercise to exhaustion as well as on the anaerobic threshold at the blood lactate level of 4 mmol.l-1 (AT) and the individual anaerobic threshold (IAT) was investigated in eight cross-country skiers. During exercise preceded by warming-up, the mean skin temperature (T sk) and external auditory canal temperature (Tac) did not change significantly in contrast to exercise without warming-up, producing a rise in both T sk and Tac (by approx. 1.2 degrees C and 1.1 degrees C, respectively). Warming-up did not alter the course of the rectal temperature changes during exercise. With warming-up skin humidity rose immediately after the beginning of exercise, whereas the onset of sweating without warming-up appeared much later at higher work intensities. Warming-up did not change the circulatory and ventilatory responses to incremental exercise and the oxygen uptake (VO2) either at submaximal or maximal work loads. With warming-up a significant increase was found in the threshold work load both at the AT and the IAT. The data demonstrated that warming-up has an advantageous effect on the efficiency of thermoregulation in endurance-trained athletes producing an early sweating response to the incremental exercise that results in attenuation of hyperthermia. An increase in the anaerobic threshold during incremental exercise preceded by warming-up may indicate an enhancement of the endurance capacity subsequent to warming-up. |
3,056 | 255 | 26035255 | Name monoclonal antibody against SLAMF7. | Elotuzumab Therapy for Relapsed or Refractory Multiple Myeloma. BACKGROUND: Elotuzumab, an immunostimulatory monoclonal antibody targeting signaling lymphocytic activation molecule F7 (SLAMF7), showed activity in combination with lenalidomide and dexamethasone in a phase 1b-2 study in patients with relapsed or refractory multiple myeloma. METHODS: In this phase 3 study, we randomly assigned patients to receive either elotuzumab plus lenalidomide and dexamethasone (elotuzumab group) or lenalidomide and dexamethasone alone (control group). Coprimary end points were progression-free survival and the overall response rate. Final results for the coprimary end points are reported on the basis of a planned interim analysis of progression-free survival. RESULTS: Overall, 321 patients were assigned to the elotuzumab group and 325 to the control group. After a median follow-up of 24.5 months, the rate of progression-free survival at 1 year in the elotuzumab group was 68%, as compared with 57% in the control group; at 2 years, the rates were 41% and 27%, respectively. Median progression-free survival in the elotuzumab group was 19.4 months, versus 14.9 months in the control group (hazard ratio for progression or death in the elotuzumab group, 0.70; 95% confidence interval, 0.57 to 0.85; P<0.001). The overall response rate in the elotuzumab group was 79%, versus 66% in the control group (P<0.001). Common grade 3 or 4 adverse events in the two groups were lymphocytopenia, neutropenia, fatigue, and pneumonia. Infusion reactions occurred in 33 patients (10%) in the elotuzumab group and were grade 1 or 2 in 29 patients. CONCLUSIONS: Patients with relapsed or refractory multiple myeloma who received a combination of elotuzumab, lenalidomide, and dexamethasone had a significant relative reduction of 30% in the risk of disease progression or death. (Funded by Bristol-Myers Squibb and AbbVie Biotherapeutics; ELOQUENT-2 ClinicalTrials.gov number, NCT01239797.). |
3,060 | 256 | 24563587 | What is the mode of action of bedaquiline? | Bedaquiline - The first ATP synthase inhibitor against multi drug resistant tuberculosis. Increasing incidence of MDR-TB, long duration of treatment and co-infection with HIV are the significant problems in achieving the eradication of tuberculosis. Bedaquiline is an anti-tuberculosis drug with unique mechanism of action. It selectively inhibits the mycobacterial energy metabolism i.e. ATP synthesis and found to be effective against all states of Mycobacterium tuberculosis like active, dormant, replicating, non-replicating, intracellular and extracellular. Preclinical studies have shown the efficacy of bedaquiline in terms of reduction in bacterial load and treatment duration. Phase II clinical studies have established the safety, tolerability and earlier sputum conversion time in patients with MDR-TB. In 2012 FDA approved bedaquiline for treatment of MDR-TB and XDR-TB. |
3,066 | 257 | 18988408 | Does helicobacter pylori infection increase risk for ischemic stroke? | Helicobacter pylori gastritis and risk of ischaemic stroke. OBJECTIVE: To identify the association between H. Pylori gastritis and stroke. METHOD: Patients with biopsy proven H. Pylori gastritis and non H. Pylori gastritis were enrolled. Patients were followed for a period of two years. RESULTS: A total of 326 patients were included in the study. 162 patients were with H. Pylori gastritis. There was no significance difference in age, sex and duration of symptoms in the two groups. Three patients in H. Pylori group had stroke or TIA as compared to one in non H. Pylori group. Patients with H. Pylori gastritis were more likely to die or have cardiac and or neurological event as compared to Non H. pylori gastritis (OR 1.23, 95% CI 0.89-1.67). This relationship was not significant after adjusting for cardiovascular risk factors (AOR 0.85, 95% CI 0.45-1.31). CONCLUSION: H. Pylori gastritis is not independently associated with increased risk for stroke. Larger, randomized studies are needed to confirm our findings. |
3,097 | 258 | 1809779 | Which are the major types of the motor speech disorder dysarthria? | Dysarthria of motor neuron disease: longitudinal measures of segmental durations. Motor neuron disease encompasses a group of terminal, demyelinating diseases affecting upper- and lower-motor neurons and producing muscular weakness resulting in a flaccid, spastic, or spastic-flaccid dysarthria of speech. The present study presents measurements of the temporal-acoustic characteristics of dysarthria in three subjects with Motor Neuron Disease over a two-year recording period. Changes seen over the course of the disease varied by type of motor neuron disease, though all types demonstrated some degree of neutralization of the prevocalic VOT, target vowel duration, and postvocalic closure duration. These changes are discussed with relation to physical manifestation and progression of the disease. |
3,112 | 259 | 16709600 | Is oxidative stress affected by FOXO expression? | Differential expression of FOXO1 and FOXO3a confers resistance to oxidative cell death upon endometrial decidualization. The integrity of the feto-maternal interface is critical for survival of the conceptus. This interface, consisting of the maternal decidua and the invading placental trophoblast, is exposed to profound changes in oxygen tension during pregnancy. We demonstrate that human endometrial stromal cells become extraordinarily resistant to oxidative stress-induced apoptosis upon decidualization in response to cAMP and progesterone signaling. This differentiation process is associated with the induction of the forkhead transcription factor FOXO1, which in turn increases the expression of the mitochondrial antioxidant manganese superoxide dismutase. However, silencing of FOXO1 did not increase the susceptibility of decidualized cells to oxidative cell death. Comparative analysis demonstrated that hydrogen peroxide, a source of free radicals, strongly induces FOXO3a mRNA and protein expression in undifferentiated human endometrial stromal cells but not in decidualized cells. Expression of a constitutively active FOXO3a mutant elicited apoptosis in decidualized cells. Furthermore, silencing of endogenous FOXO3a in undifferentiated cells abrogated apoptosis induced by hydrogen peroxide. These results suggest that the induction of FOXO1 may enhance the ability of decidualized cells to prevent oxidative damage while the simultaneous repression of FOXO3a expression disables the signaling pathway responsible for oxidative cell death. The differential regulation of FOXO expression provides the decidua with a robust system capable of coping with prolonged episodes of oxidative stress during pregnancy. |
3,116 | 260 | 23155537 | Describe the mechanism of action of the LINX system for treatment of gastroesophageal reflux disease. | [Treatment of gastroesophageal reflux disease: comments from thoracic surgeon]. Gastroesophageal reflux disease (GERD) is the most common gastrointestinal diagnosis recorded during visits to outpatient clinics in west countries. The prevalence of symptom-defined GERD in China is as high as 3% to 5%. Asa dysfunction, GERD is characterized by reflux and heartburn. The pathophysiologic process of GERD is very complicated and subtle. The spectrum of injury from long-term reflux of acid or bile includes damage mucosa, Barrett's esophagus, dysplasia, and esophageal cancer. Therefore, the therapies of GERD should focus on controlling symptom,treating complications, and surveillance the possibility of oncologic transform. As with therapy with proton-pump inhibitors (PPI), modifying lifestyle is another most important modality for most GERD. The window of surgical treatment for GERD is narrow. Surgical therapy is alternative management approach to the patients with PPI failure, complications, or huge hernia. The laparoscopic minimally invasive procedure improves the acceptance of patients to surgical therapy, but the long-term complication and drawbacks of anti-reflux surgery cannot be ignored, and which is even more common than open procedures. The limitations of current therapy for GERD have encouraged a search for more effective treatment.The Linx sphincter augmentation device has been developed to address this gap with improvement of the barrier function of LES and reversible design if necessary. |
3,128 | 261 | 10571006 | Which enzyme deficiency can cause GM1 gangliosidoses? | Molecular basis of GM1 gangliosidosis and Morquio disease, type B. Structure-function studies of lysosomal beta-galactosidase and the non-lysosomal beta-galactosidase-like protein. GM1 gangliosidosis and Morquio B disease are distinct disorders both clinically and biochemically yet they arise from the same beta-galactosidase enzyme deficiency. On the other hand, galactosialidosis and sialidosis share common clinical and biochemical features, yet they arise from two separate enzyme deficiencies, namely, protective protein/cathepsin A and neuraminidase, respectively. However distinct, in practice these disorders overlap both clinically and biochemically so that easy discrimination between them is sometimes difficult. The principle reason for this may be found in the fact that these three enzymes form a unique complex in lysosomes that is required for their stability and posttranslational processing. In this review, I focus mainly on the primary and secondary beta-galactosidase deficiency states and offer some hypotheses to account for differences between GM1 gangliosidosis and Morquio B disease. |
3,144 | 262 | 25207154 | What is the characteristic feature of the Dyke-Davidoff-Masson syndrome. | Dyke-davidoff-masson syndrome associated with epidermoid tumour and arachnoid cyst: a case report. BACKGROUND: Dyke-Davidoff-Masson Syndrome (DDMS) is a rarely seen clinical entity which is characterised by cerebral hemiatrophy, contralateral hemiparesis and epilepsy. Radiological features are typical, such as unilateral atrophy of the cerebral hemisphere and associated compensatory bone changes in the skull, like thickening, enlargement of the paranasal sinuses and mastoid air cells. CASE REPORT: In this article, we report the first case of DDMS associated with epidermoid tumour and arachnoid cyst, who underwent operation for an epidermoid tumour in the inter-hemispheric region. To our knowledge, this is the first report of DDMS associated with multiple intracranial pathologies and this association has not been previously described in the literature. CONCLUSION: Any patient who receives DDMS in the light of clinical and radiological findings should be investigated for concomitant pathologies. Different sequences of MRI may be useful in the diagnosis of other intracranial lesions. |
3,176 | 263 | 20981509 | Which gene is involved in the development of Barth syndrome? | Barth syndrome: an X-linked cardiomyopathy with a novel mutation. The authors report a 6 yr old boy with Barth syndrome who presented with cardiomyopathy, neutropenia and hypotonia. Urine gas chromatography showed high level of 3-methylglutaconic acid. The DNA of both the patient and the mother showed a heterozygous 3 bp deletion in exon 8 of the tafazzin gene. This abnormality involves the deletion of the bases TGA starting at cDNA nucleotide 891 (c891_893delTGA), resulting in the absence of glutamic acid at codon 202 from a highly conserved area of the tafazzin protein, consistent with the diagnosis of Barth syndrome. This is the first case report of Barth syndrome in Arab population emphasizing the importance of detailed investigations in cases of hereditary cardiomyopathy. |
3,189 | 264 | 17923793 | What is the treatment of subacute thyroiditis? | Subacute thyroiditis: clinical characteristics and treatment outcome in fifty-six consecutive patients diagnosed between 1999 and 2005. OBJECTIVE: To identify predictive factors of clinical outcome of subacute thyroiditis. DESIGN: Retrospective case series of 56 consecutive patients treated in 3 outpatient clinics between 1999 and 2005. Medical records were reviewed for demographic data, seasonal disease distribution, laboratory and clinical course, treatment, and short-term outcome. MAIN OUTCOME: Mean age was 48.6+/-12 yr; 70% were females. Twenty-five percent had antithyroid antibodies and 9% had recurrent disease. Differences in occurrence by season were not significant (p=0.28). Ultrasound, performed in 35 patients, revealed thyroid nodules in 25 (median size, 17 mm). Ten patients received no treatment, and 43 received either non-steroidal anti-inflammatory drugs (NSAID) (no.=25) or glucocorticoids (no.=18); data for 3 patients were missing. Median disease duration was 77 days; mean peak free T4 (FT4) level was 43.7+/-25.3 pmol/l. A hypothyroid phase was documented in 31 patients, and remained permanent in 6. Peak FT4 level, but not erythrocyte sedimentation rate or clinical score, was positively correlated with the highest TSH level and with disease duration. Untreated patients had less severe clinical disease than treated patients, but a similar outcome. Patients given glucocorticoids had a shorter overall disease duration (p=0.03), with no differences in duration of hyperthyroidism, peak FT4 or highest TSH levels, compared with patients given NSAID. CONCLUSION: Subacute thyroiditis follows an unpredictable clinical course that is hardly affected by its clinical features or treatment. |
3,193 | 265 | 22611086 | What are the effects of BMAL1 deficiency? | The clock gene, brain and muscle Arnt-like 1, regulates adipogenesis via Wnt signaling pathway. Circadian clocks in adipose tissue are known to regulate adipocyte biology. Although circadian dysregulation is associated with development of obesity, the underlying mechanism has not been established. Here we report that disruption of the clock gene, brain and muscle Arnt-like 1 (Bmal1), in mice led to increased adipogenesis, adipocyte hypertrophy, and obesity, compared to wild-type (WT) mice. This is due to its cell-autonomous effect, as Bmal1 deficiency in embryonic fibroblasts, as well as stable shRNA knockdown (KD) in 3T3-L1 preadipocyte and C3H10T1/2 mesenchymal stem cells, promoted adipogenic differentiation. We demonstrate that attenuation of Bmal1 function resulted in down-regulation of genes in the canonical Wnt pathway, known to suppress adipogenesis. Promoters of these genes (Wnt10a, β-catenin, Dishevelled2, TCF3) displayed Bmal1 occupancy, indicating direct circadian regulation by Bmal1. As a result, Wnt signaling activity was attenuated by Bmal1 KD and augmented by its overexpression. Furthermore, stabilizing β-catenin through Wnt ligand or GSK-3β inhibition achieved partial restoration of blunted Wnt activity and suppression of increased adipogenesis induced by Bmal1 KD. Taken together, our study demonstrates that Bmal1 is a critical negative regulator of adipocyte development through transcriptional control of components of the canonical Wnt signaling cascade, and provides a mechanistic link between circadian disruption and obesity. |
3,199 | 266 | 23104054 | Which histone modifications are associated with Polycomb group (PcG) proteins? | Phf19 links methylated Lys36 of histone H3 to regulation of Polycomb activity. Polycomb-group proteins are transcriptional repressors with essential roles in embryonic development. Polycomb repressive complex 2 (PRC2) contains the methyltransferase activity for Lys27. However, the role of other histone modifications in regulating PRC2 activity is just beginning to be understood. Here we show that direct recognition of methylated histone H3 Lys36 (H3K36me), a mark associated with activation, by the PRC2 subunit Phf19 is required for the full enzymatic activity of the PRC2 complex. Using NMR spectroscopy, we provide structural evidence for this interaction. Furthermore, we show that Phf19 binds to a subset of PRC2 targets in mouse embryonic stem cells and that this is required for their repression and for H3K27me3 deposition. These findings show that the interaction of Phf19 with H3K36me2 and H3K36me3 is essential for PRC2 complex activity and for proper regulation of gene repression in embryonic stem cells. |
3,206 | 267 | 21055175 | Where is the protein CLIC1 localized? | [Localization and expression of CLIC1 in hepatocarcinoma ascites cell lines with high or low potentials of lymphatic spread]. OBJECTIVE: To study the localization and expression of CLIC1 in mouse hepatocarcinoma ascites cell lines with different metastatic potentials. METHODS: Mouse hepatocarcinoma ascites models (a high potential of lymphatic metastasis cell line-Hca-F, and a low potential of lymphatic metastasis cell line-Hca-P) were investigated using fluorescent two-dimensional difference-gel electrophoresis (2-D DIGE) and mass spectrometry for detecting the localization and expression of CLIC1. Immunofluorescence, immunocytochemistry and Western blot were used to assess CLIC1 protein status in the two cell lines. RESULTS: CLIC1 expression was obtained in the cytoplasm and plasma membrane of cells in both cell lines. 2-D DIGE showed that CLIC1 was overexpressed in Hca-F cells, 1.6 folds higher than that of the Hca-P cells. Hca-F cells also had a higher integral membrane CLIC1 in the Hca-P cells. CONCLUSIONS: Although CLIC1 expression is detected in both Hca-F and Hca-P cell lines, a higher protein expression level is present in Hca-F cells. CLIC1 may play an important role in tumor metastasis. |
3,209 | 268 | 8055935 | List phosphorylation consensus motifs for Casein Kinase 1 (CK1)? | Phosphorylation of synthetic fragments of inhibitor-2 of protein phosphatase-1 by casein kinase-1 and -2. Evidence that phosphorylated residues are not strictly required for efficient targeting by casein kinase-1. The major phosphorylation site for both casein kinase-2 (CK2) and casein kinase-1 (CK1) in protein phosphatase-1 (PP-1) inhibitor-2 (I-2) is Ser86. Minor phosphorylation sites affected by either CK2 or CK1 are Ser120/Ser121 and Ser174, respectively. A synthetic peptide of 25 amino acids encompassing residues 67-93 of I-2 is phosphorylated by either CK2 or CK1 at its seryl residue corresponding to Ser86 with higher Vmax and Km values similar to those of the intact protein (9 vs 7.2 microM and 14.2 vs 5.3 microM with CK2 and CK1, respectively). No detectable phosphorylation of this peptide which also includes the glycogen synthase kinase-3 (GSK-3) site (Thr72), could be observed with either GSK-3 or p34cdc2 kinase whether or not its seryl residue equivalent to Ser86 had been previously phosphorylated by CK2. Shorter derivatives of I-2(67-93), encompassing residues 72-93 and 78-93, are also readily phosphorylated by both CK1 and CK2, with phosphorylation efficiencies similar to those of the parent peptide. A synthetic heptadecapeptide reproducing the phosphoacceptor site around Ser120/Ser121 is phosphorylated by CK2, but not to any detectable extent by CK1, with a Km value fivefold higher than that of the corresponding pentadecapeptide including Ser86 (78-93). A synthetic pentadecapeptide (166-180) reproducing the phosphoacceptor site around Ser174 is phosphorylated by CK1 less efficiently than the pentadecapeptide including its main phosphorylation site (78-93) (Km 280 microM vs 33 microM). This peptide is readily phosphorylated by CK2 as well, although it lacks the canonical consensus sequence for CK2 and its Ser174 is almost unaffected by CK2 in intact I-2. These data provide the clear-cut demonstration that the consensus sequence with N-terminal prephosphorylated residue(s), SerP/ThrP-Xaa-Xaa-Ser/Thr, [Flotow, H., Graves, P. R., Wang, A., Fiol, C. J., Roeske, R. W. & Roach, P. J. (1990) J. Biol. Chem. 265, 14264-14269; Meggio, F., Perich, J. W., Reynolds, E. C. & Pinna, L. A. (1991) FEBS Lett. 283, 303-306] is not always required to achieve efficient and high-affinity phosphorylation by CK1. They also show that the specificity determinants for I-2 phosphorylation by either CK2 or CK1, but not by GSK3, are entirely grounded on local structural features of the phosphoacceptor site, being only marginally affected by the overall structure of I-2. |
3,216 | 269 | 23352688 | What medication were compared in the ROCKET AF Trial? | Rivaroxaban versus warfarin in Japanese patients with nonvalvular atrial fibrillation for the secondary prevention of stroke: a subgroup analysis of J-ROCKET AF. BACKGROUND: The overall analysis of the rivaroxaban versus warfarin in Japanese patients with atrial fibrillation (J-ROCKET AF) trial revealed that rivaroxaban was not inferior to warfarin with respect to the primary safety outcome. In addition, there was a strong trend for a reduction in the rate of stroke/systemic embolism with rivaroxaban compared with warfarin. METHODS: In this subanalysis of the J-ROCKET AF trial, we investigated the consistency of safety and efficacy profile of rivaroxaban versus warfarin among the subgroups of patients with previous stroke, transient ischemic attack, or non-central nervous system systemic embolism (secondary prevention group) and those without (primary prevention group). RESULTS: Patients in the secondary prevention group were 63.6% of the overall population of J-ROCKET AF. In the secondary prevention group, the rate of the principal safety outcome (% per year) was 17.02 in rivaroxaban-treated patients and 18.26 in warfarin-treated patients (hazard ratio [HR] 0.95; 95% confidence interval [CI] 0.70-1.29), while the rate of the primary efficacy endpoint was 1.66 in rivaroxaban-treated patients and 3.25 in warfarin-treated patients (HR 0.51; 95% CI 0.23-1.14). There were no significant interactions in the principal safety and the primary efficacy endpoints of rivaroxaban compared to warfarin between the primary and secondary prevention groups (P=.090 and .776 for both interactions, respectively). CONCLUSIONS: The safety and efficacy profile of rivaroxaban compared with warfarin was consistent among patients in the primary prevention group and those in the secondary prevention group. |
3,236 | 270 | 21097778 | Describe the usefulness of the SPIKE database in human signaling pathways | SPIKE: a database of highly curated human signaling pathways. The rapid accumulation of knowledge on biological signaling pathways and their regulatory mechanisms has highlighted the need for specific repositories that can store, organize and allow retrieval of pathway information in a way that will be useful for the research community. SPIKE (Signaling Pathways Integrated Knowledge Engine; http://www.cs.tau.ac.il/&~spike/) is a database for achieving this goal, containing highly curated interactions for particular human pathways, along with literature-referenced information on the nature of each interaction. To make database population and pathway comprehension straightforward, a simple yet informative data model is used, and pathways are laid out as maps that reflect the curator’s understanding and make the utilization of the pathways easy. The database currently focuses primarily on pathways describing DNA damage response, cell cycle, programmed cell death and hearing related pathways. Pathways are regularly updated, and additional pathways are gradually added. The complete database and the individual maps are freely exportable in several formats. The database is accompanied by a stand-alone software tool for analysis and dynamic visualization of pathways. |
3,238 | 271 | 16875414 | Is the Dictyostelium discoideum proteome known? | The Dictyostelium genome. The 34 Mb genome of Dictyostelium discoideum is carried on 6 chromosomes and has been fully sequenced by an international consortium. The sequence was assembled on the classical and physical maps that had been built up over the years and refined by HAPPY mapping. Annotation of the sequence predicted about 12,000 genes for proteins of at least 50 amino acids in length. The total number of amino acids encoded (the proteome) is more than double that in yeast and rivals that of metazoans. The genome sequence shows all the proteins available to Dictyostelium as well as definitively showing which domains have been lost since Dictyostelium diverged from the line leading to metazoans. Genomics opens the door to determining the expression patterns of all the genes during growth and development using microarrays. This approach has already uncovered a wealth of new markers for the stages of development and the various cell types. Transcription factors and their cis-regulatory sites that account for the surprising complexity of Dictyostelium development can be analyzed much more easily now that we have the complete sequence. |
3,247 | 272 | 23204327 | List proteins of lipids droplets | Distinct mechanisms regulate ATGL-mediated adipocyte lipolysis by lipid droplet coat proteins. Adipose triglyceride lipase (ATGL) is the key triacylglycerol hydrolase in adipocytes. The precise mechanisms by which ATGL action is regulated by lipid droplet (LD) coat proteins and responds to hormonal stimulation are incompletely defined. By combining usage of loss- and gain-of-function approaches, we sought to determine the respective roles of perilipin 1 and fat-specific protein 27 (FSP27) in the control of ATGL-mediated lipolysis in adipocytes. Knockdown of endogenous perilipin 1 expression resulted in elevated basal lipolysis that was less responsive to β-adrenergic agonist isoproterenol. In comparison, depletion of FSP27 protein increased both basal and stimulated lipolysis with no significant impact on the overall response of cells to isoproterenol. In vitro assays showed that perilipin but not FSP27 was able to inhibit the triacylglycerol hydrolase activity of ATGL. Perilipin 1 also attenuated dose-dependent activation of ATGL by its Coactivator Comparative Gene identification-58. Accordingly, depletion of perilipin 1 and CGI-58 in adipocytes inversely affected basal lipolysis specifically mediated by overexpressed ATGL. Moreover, although depletion of perilipin 1 abolished the LD translocation of ATGL stimulated by isoproterenol, absence of FSP27 resulted in multilocularization of LDs along with increased LD presence of ATGL under both basal and stimulated conditions. Interestingly, knockdown of ATGL expression increased LD size and decreased LD number in FSP27-depeleted cells. Together, our results demonstrate that although FSP27 acts to constitutively limit the LD presence of ATGL, perilipin 1 plays an essential role in mediating the response of ATGL action to β-adrenergic hormones. |
3,255 | 273 | 21416650 | What is the Barr body? | Barr body in fine needle aspiration cytology of ovarian malignancies. The Barr body is the inactive X chromosome in a female somatic cell. It is readily identified as plano-convex structure of 2-3 micron in diameter on the periphery of the nuclear membrane. The aim of this study is to evaluate the significance of Barr body count in malignant ovarian tumors on fine needle aspiration cytology (FNAC) smears. In this retrospective study, Barr body was counted in FNAC smears of 20 successive malignant ovarian lesions and expressed as percentage. Mean (±SD) Barr body score was 2.4 ± 2.58. Minimum Barr body count was 1 and maximum was 9. The gross reduction of Barr body in ovarian neoplasms is an interesting cytomorphologic finding. |
3,269 | 274 | 18392595 | Is single-cell analysis (SCA) possible in proteomics? | Multi-dimensional capillary electrophoresis and chromatography for proteomic analysis. Comprehensive two-dimensional liquid chromatography-capillary electrophoresis systems are summarized in this chapter. A variety of combinations of capillary electrophoresis and liquid chromatography modes as well as interfaces and detection technologies are discussed. A typical, comprehensive two-dimensional system coupled with reverse-phase liquid chromatography with fast capillary electrophoresis and hyphenated to mass spectrometry was demonstrated for proteomic analysis. A two-dimensional capillary electrophoresis system of coupling capillary sieving electrophoresis with micellar electrokinetic chromatography and its application in single cell analysis for protein expression profiling are presented. |
3,290 | 275 | 17920553 | Is shotgun lipidomics the direct infusion of a lipid sample into a mass spectrometer? | Alkaline methanolysis of lipid extracts extends shotgun lipidomics analyses to the low-abundance regime of cellular sphingolipids. Sphingolipids that contain a sphingoid base are composed of hundreds to thousands of distinct compounds, many of which serve as lipid regulators of biological functions. The global analysis of the large number of low-abundance sphingolipid molecular species has been hampered in many cases by the sphingolipid molecular species being overwhelmed by the quantity of other classes of lipid (e.g., glycerophospholipid) molecular species present, thereby imposing severe restrictions on the dynamic range of their measurement using shotgun lipidomics. Herein, we developed a facile approach in which the sphingolipids of cellular extracts were dramatically enriched by direct alkaline methanolysis of lipid extracts followed by extraction to remove the large majority of other endogenous lipid classes. Through direct infusion of the resultant enriched solution, we identified and quantitated a variety of very-low-abundance sphingolipid classes (e.g., sphingosine, psychosine, and lysosphingomyelin) and molecular species (e.g., sphingomyelin) using electrospray ionization mass spectrometry (i.e., shotgun sphingolipidomics). Accordingly, through utilization of these facile enrichment techniques, direct penetrance into the sphingolipidomes has been greatly extended, facilitating new insights into their metabolism and signaling functions in biological systems. |
3,298 | 276 | 22553468 | How many genes are in the gene signature screened by MammaPrint? | The 70-Gene Signature as Prognostic Factor for Elderly Women with Hormone Receptor-Positive, HER2-Negative Breast Cancer. BACKGROUND: The aim of this article was to evaluate the prognostic value of the MammaPrint(TM) signature in women $$ 60 years with invasive breast cancer. PATIENTS AND METHODS: 60 female patients were included in this prospective study. Eligibility criteria included: pT1c-3, pN0-1a, grade 2/3, hormone receptor-positive and HER2-negative tumor. The clinical risk was determined by Adjuvant! Online (AOL). RESULTS: 38 patients (63%) where considered to be low-risk patients by the 70-gene signature, while 22 (37%) were considered to be high-risk patients. No statistically significant differences between low- and high-risk groups could be detected for conventional prognostic parameters, particularly not for Ki-67. By AOL, 33 patients (55%) were considered to be at high risk, of which 20 had a discordant MammaPrint(TM) result. The discordance rate between the profile and AOL was 48%, which is higher than in previous publications. When the 70-gene signature was used in combination with the clinical risk assessment, the recommendation for adjuvant systemic treatment differed in 11 patients (18%). CONCLUSIONS: In the intermediate-risk subgroup, the 70-gene signature could be useful to decide in elderly patients whether they may benefit from adjuvant chemotherapy or not. Conventional clinicopathological factors were not suitable for a prediction of the 70-gene signature results in these patients. |
3,314 | 277 | 18393142 | Is apixaban effective for treatment of acute venous thromboembolism? | Current and future prospects for anticoagulant therapy: inhibitors of factor Xa and factor IIa. Indirect systemic and direct oral factor Xa and direct oral factor IIa inhibitors with improved pharmacologic profiles compared with heparins and vitamin K antagonists are currently in clinical development. This overview focuses on the indirect antithrombin dependent pentasaccharide derivatives of idraparinux and on the most advanced oral direct inhibitors to factor Xa (rivaroxaban and apixaban) and IIa (dabigatran). Specifically, the results of dose-finding studies for the prevention of venous thromboembolism after elective orthopedic surgery, the results of dose-finding studies for treatment of acute venous thromboembolism including prolonged prophylaxis of recurrent events, and the designs of ongoing clinical trials are reviewed. |
3,328 | 278 | 23776651 | Is the tricarboxylic acid (TCA) cycle affected in inflammation? | Inflammation and resolution are associated with upregulation of fatty acid β-oxidation in Zymosan-induced peritonitis. Inflammation is a fundamental defensive response to harmful stimuli. However, it can cause damage if it does not subside. To avoid such damage, organisms have developed a mechanism called resolution of inflammation. Here we applied an untargeted metabolomics approach to a sterile and self-resolving animal model of acute inflammation, namely zymosan-induced peritonitis in mice, to examine the effect of inflammation and resolution on the metabolomic profiles. Significant and time-dependent changes in metabolite profiles after zymosan administration were observed in both peritoneal wash fluid (PWF) and plasma. These metabolomic changes correlated well with inflammatory chemokine or cytokine production. In PWF, most of metabolites that could detected increased in zymosan-treated mice, which is suggestive of inflammation, oxidative stress and increased energy demands. In plasma, most metabolites in the central metabolic pathway (glycolysis and TCA cycle) were significantly downregulated after zymosan administration. The concentration of the ketone body 3-hydroxybutyric acid (3-HB) in plasma and PWF increased in zymosan-injected animals indicating upregulation of fatty acid β-oxidation. Increased 3-HB level was observed in the cells that infiltrated into the peritoneal cavity and these infiltrated cells might contribute, at least in part, to the production of 3-HB in the peritoneal cavity. |
3,338 | 279 | 24231125 | What are the indications for treatment with anti-hepcidin? | Hepcidin levels in chronic hemodialysis patients: a critical evaluation. Altered systemic iron metabolism is a key element of uremia, and functional iron deficiency mainly related to subclinical inflammation makes it difficult to maintain proper control of anemia in chronic hemodialysis patients (CHD). In the last decade, the hepatic hormone hepcidin has been progressively recognized as the master regulator of circulating iron levels through the modulation of cellular iron fluxes in response to iron stores, as well as to erythroid and inflammatory stimuli. Hepcidin is cleared by the kidney and progression of renal disease has been associated to increased serum hepcidin levels. This, in turn, reduces iron availability for erythropoiesis, suggesting anti-hepcidin strategies for improving anemia control. Moreover, hepcidin has been recently implicated in the pathogenesis of long-term complications of dialysis, like accelerated atherosclerosis. Initial studies almost invariably reported a sustained increase of serum hepcidin in chronic hemodialysis patients. Noteworthy, such studies included relatively few patients and controls that were poorly matched for major determinants of serum hepcidin at population level, i.e., age and gender. More recent data based on accurately matched larger series challenge the view that hepcidin is intrinsically increased in hemodialysis patients, showing a marked inter- and intra-individual variability of hormone levels. Here we take a critical look to the data published so far on hepcidin levels in CHD, analyze the reasons underlying the discrepancies in available studies and the hepcidin variability in CHD, and point out the need for further studies in large series of well-characterized CHD patients and controls. |
3,341 | 280 | 21249176 | How many genera comprise the Flaviviridae family? | Identification and characterization of the host protein DNAJC14 as a broadly active flavivirus replication modulator. Viruses in the Flavivirus genus of the Flaviviridae family are arthropod-transmitted and contribute to staggering numbers of human infections and significant deaths annually across the globe. To identify cellular factors with antiviral activity against flaviviruses, we screened a cDNA library using an iterative approach. We identified a mammalian Hsp40 chaperone protein (DNAJC14) that when overexpressed was able to mediate protection from yellow fever virus (YFV)-induced cell death. Further studies revealed that DNAJC14 inhibits YFV at the step of viral RNA replication. Since replication of bovine viral diarrhea virus (BVDV), a member of the related Pestivirus genus, is also known to be modulated by DNAJC14, we tested the effect of this host factor on diverse Flaviviridae family members. Flaviviruses, including the pathogenic Asibi strain of YFV, Kunjin, and tick-borne Langat virus, as well as a Hepacivirus, hepatitis C virus (HCV), all were inhibited by overexpression of DNAJC14. Mutagenesis showed that both the J-domain and the C-terminal domain, which mediates self-interaction, are required for anti-YFV activity. We found that DNAJC14 does not block YFV nor HCV NS2-3 cleavage, and using non-inhibitory mutants demonstrate that DNAJC14 is recruited to YFV replication complexes. Immunofluorescence analysis demonstrated that endogenous DNAJC14 rearranges during infection and is found in replication complexes identified by dsRNA staining. Interestingly, silencing of endogenous DNAJC14 results in impaired YFV replication suggesting a requirement for DNAJC14 in YFV replication complex assembly. Finally, the antiviral activity of overexpressed DNAJC14 occurs in a time- and dose-dependent manner. DNAJC14 overexpression may disrupt the proper stoichiometry resulting in inhibition, which can be overcome upon restoration of the optimal ratios due to the accumulation of viral nonstructural proteins. Our findings, together with previously published work, suggest that the members of the Flaviviridae family have evolved in unique and important ways to interact with this host Hsp40 chaperone molecule. |
3,352 | 281 | 26422724 | Are reduced-nicotine cigarettes effective for smoking cessation? | Randomized Trial of Reduced-Nicotine Standards for Cigarettes. BACKGROUND: The Food and Drug Administration can set standards that reduce the nicotine content of cigarettes. METHODS: We conducted a double-blind, parallel, randomized clinical trial between June 2013 and July 2014 at 10 sites. Eligibility criteria included an age of 18 years or older, smoking of five or more cigarettes per day, and no current interest in quitting smoking. Participants were randomly assigned to smoke for 6 weeks either their usual brand of cigarettes or one of six types of investigational cigarettes, provided free. The investigational cigarettes had nicotine content ranging from 15.8 mg per gram of tobacco (typical of commercial brands) to 0.4 mg per gram. The primary outcome was the number of cigarettes smoked per day during week 6. RESULTS: A total of 840 participants underwent randomization, and 780 completed the 6-week study. During week 6, the average number of cigarettes smoked per day was lower for participants randomly assigned to cigarettes containing 2.4, 1.3, or 0.4 mg of nicotine per gram of tobacco (16.5, 16.3, and 14.9 cigarettes, respectively) than for participants randomly assigned to their usual brand or to cigarettes containing 15.8 mg per gram (22.2 and 21.3 cigarettes, respectively; P<0.001). Participants assigned to cigarettes with 5.2 mg per gram smoked an average of 20.8 cigarettes per day, which did not differ significantly from the average number among those who smoked control cigarettes. Cigarettes with lower nicotine content, as compared with control cigarettes, reduced exposure to and dependence on nicotine, as well as craving during abstinence from smoking, without significantly increasing the expired carbon monoxide level or total puff volume, suggesting minimal compensation. Adverse events were generally mild and similar among groups. CONCLUSIONS: In this 6-week study, reduced-nicotine cigarettes versus standard-nicotine cigarettes reduced nicotine exposure and dependence and the number of cigarettes smoked. (Funded by the National Institute on Drug Abuse and the Food and Drug Administration Center for Tobacco Products; ClinicalTrials.gov number, NCT01681875.). |
3,363 | 282 | 18505598 | Is the Wnt protein modified by notum? | Glypicans. SUMMARY: Glypicans are heparan sulfate proteoglycans that are bound to the outer surface of the plasma membrane by a glycosyl-phosphatidylinositol anchor. Homologs of glypicans are found throughout the Eumetazoa. There are six family members in mammals (GPC1 to GPC6). Glypicans can be released from the cell surface by a lipase called Notum, and most of them are subjected to endoproteolytic cleavage by furin-like convertases. In vivo evidence published so far indicates that the main function of membrane-attached glypicans is to regulate the signaling of Wnts, Hedgehogs, fibroblast growth factors and bone morphogenetic proteins (BMPs). Depending on the context, glypicans may have a stimulatory or inhibitory activity on signaling. In the case of Wnt, it has been proposed that the stimulatory mechanism is based on the ability of glypicans to facilitate and/or stabilize the interaction of Wnts with their signaling receptors, the Frizzled proteins. On the other hand, GPC3 has recently been reported to inhibit Hedgehog protein signaling during development by competing with Patched, the Hedgehog receptor, for Hedgehog binding. Surprisingly, the regulatory activity of glypicans in the Wnt, Hedgehog and BMP signaling pathways is only partially dependent on the heparan sulfate chains. |
3,372 | 283 | 24556655 | List functions that are evaluated with the Full Outline of Unresponsiveness score? | A pediatric FOUR score coma scale: interrater reliability and predictive validity. The Full Outline of UnResponsiveness (FOUR) Score is a coma scale that consists of four components (eye and motor response, brainstem reflexes, and respiration). It was originally validated among the adult population and recently in a pediatric population. To enhance clinical assessment of pediatric intensive care unit patients, including those intubated and/or sedated, at our children's hospital, we modified the FOUR Score Scale for this population. This modified scale would provide many of the same advantages as the original, such as interrater reliability, simplicity, and elimination of the verbal component that is not compatible with the Glasgow Coma Scale (GCS), creating a more valuable neurological assessment tool for the nursing community. Our goal was to potentially provide greater information than the formally used GCS when assessing critically ill, neurologically impaired patients, including those sedated and/or intubated. Experienced pediatric intensive care unit nurses were trained as "expert raters." Two different nurses assessed each subject using the Pediatric FOUR Score Scale (PFSS), GCS, and Richmond Agitation Sedation Scale at three different time points. Data were compared with the Pediatric Cerebral Performance Category (PCPC) assessed by another nurse. Our hypothesis was that the PFSS and PCPC should highly correlate and the GCS and PCPC should correlate lower. Study results show that the PFSS is excellent for interrater reliability for trained nurse-rater pairs and prediction of poor outcome and in-hospital mortality, under various situations, but there were no statistically significant differences between the PFSS and the GCS. However, the PFSS does have the potential to provide greater neurological assessment in the intubated and/or sedated patient based on the outcomes of our study. |
3,376 | 284 | 23822094 | For the constructions of which organs has 3D printing been tested? | 3D printing of rat salivary glands: The submandibular-sublingual complex. The morphology and the functionality of the murid glandular complex, composed of the submandibular and sublingual salivary glands (SSC), were the object of several studies conducted mainly using magnetic resonance imaging (MRI). Using a 4.7 T scanner and a manganese-based contrast agent, we improved the signal-to-noise ratio of the SSC relating to the surrounding anatomical structures allowing to obtain high-contrast 3D images of the SSC. In the last few years, the large development in resin melting techniques opened the way for printing 3D objects starting from a 3D stack of images. Here, we demonstrate the feasibility of the 3D printing technique of soft tissues such as the SSC in the rat with the aim to improve the visualization of the organs. This approach is useful to preserve the real in vivo morphology of the SCC in living animals avoiding the anatomical shape changes due to the lack of relationships with the surrounding organs in case of extraction. It is also harmless, repeatable and can be applied to explore volumetric changes occurring during body growth, excretory duct obstruction, tumorigenesis and regeneration processes. 3D printing allows to obtain a solid object with the same shape of the organ of interest, which can be observed, freely rotated and manipulated. To increase the visibility of the details, it is possible to print the organs with a selected zoom factor, useful as in case of tiny organs in small mammalia. An immediate application of this technique is represented by educational classes. |
3,398 | 285 | 24055829 | Is ospemifene effective for treatment of dyspareunia? | Tissue selectivity of ospemifene: pharmacologic profile and clinical implications. The multifactorial consequences of menopausal estrogen deficiency affect numerous tissues throughout the body. Supplemental hormonal therapies carry the burden of a risk/benefit ratio that must be highly individualized. Selective estrogen receptor modulators (SERMs) are estrogen receptor (ER) agonist/antagonists designed to induce benefits comparable with estrogen while minimizing adverse effects. Here, we review the estrogen agonist/antagonist profile of ospemifene, a novel triphenylethylene derivative recently approved to treat dyspareunia, a symptom of vulvar and vaginal atrophy (VVA) due to menopause, both preclinically and clinically. Ospemifene binds ERα and ERβ with approximately equal affinities. In preclinical models, ospemifene increased vaginal and uterine epithelial thickness and mucification to the same extent as estrogen. Ospemifene did not induce endometrial hyperplasia in animal models; there also was no stimulatory effect on endometrial cells. In rat and human mammary cells in vitro, ospemifene evokes a dose-dependent inhibition on estrogen-induced cell responses and cell proliferation, supporting an antiestrogenic effect in breast. In contrast, ospemifene has an estrogenic effect on bone, as seen by improved bone mineral density, strength, mass, and histomorphometry in preclinical models, consistent with improvements in markers of bone resorption and formation in postmenopausal women. Based on the preclinical evidence, ospemifene has beneficial estrogen-like effects on the vaginal epithelium, preliminary evidence to support a neutral endometrial profile, antiproliferative effects in breast, and estrogenic effects in bone. Taken together, especially regarding estrogen-like effects on the vaginal epithelium, ospemifene presents a profile of tissue-specific effects that appear novel among available SERMs and well-suited for the treatment of VVA. |
3,409 | 286 | 23859128 | Is pregabalin effective for treatment of patients with restless leg syndrome? | The long-term treatment of restless legs syndrome/Willis-Ekbom disease: evidence-based guidelines and clinical consensus best practice guidance: a report from the International Restless Legs Syndrome Study Group. A Task Force was established by the International Restless Legs Syndrome Study Group (IRLSSG) to develop evidence-based and consensus-based recommendations for the long-term pharmacologic treatment of restless legs syndrome/Willis-Ekbom disease (RLS/WED). The Task Force reviewed the results of all studies of RLS/WED treatments with durations of 6 months or longer presented at meetings over the past 2 years, posted on Web sites of pharmaceutical companies, or published in peer-reviewed journals, asking the questions, "What is the efficacy of this treatment in patients with RLS/WED?" and "What is the safety of this treatment in patients with RLS/WED?" The Task Force developed guidelines based on their review of 61 papers meeting inclusion criteria, and using a modified evidence-grading scheme. Pregabalin has been established as effective for up to 1 year in treating RLS/WED (Level A evidence). Pramipexole, ropinirole, and rotigotine have been established as effective for up to 6 months in treating RLS/WED (Level A). The following drugs have been established as probably effective (Level B) in treating RLS/WED for durations ranging from 1 to 5 years: gabapentin enacarbil, pramipexole, and ropinirole (1 year); levodopa (2 years); and rotigotine (5 years). Because of associated safety concerns, pergolide and cabergoline should not be used in the treatment of RLS/WED unless the benefits clearly outweigh the risks. Other pharmacologic therapies have insufficient evidence to support their long-term use in treating RLS/WED. The IRLSSG Task Force also developed consensus-based strategies for the prevention and treatment of complications (such as augmentation, loss of efficacy, excessive daytime sleepiness, and impulse control disorders) that may develop with the long-term pharmacologic treatment of RLS/WED. The use of either a dopamine-receptor agonist or α2δ calcium-channel ligand is recommended as the first-line treatment of RLS/WED for most patients, with the choice of agent dependent on the patient's severity of RLS/WED symptoms, cognitive status, history, and comorbid conditions. |
3,427 | 287 | 15195944 | What is the biological role of expansins in fungi? | The expression of MaEXP1, a Melilotus alba expansin gene, is upregulated during the sweetclover-Sinorhizobium meliloti interaction. Expansins are a highly conserved group of cell wall-localized proteins that appear to mediate changes in cell wall plasticity during cell expansion or differentiation. The accumulation of expansin protein or the mRNA for specific expansin gene family members has been correlated with the growth of various plant organs. Because expansin proteins are closely associated with plant cell wall expansion, and as part of a larger study to determine the role of different gene products in the legume-Rhizobium spp. symbiosis, we investigated whether a Melilotus alba (white sweetclover) expansin gene is expressed during nodule development. A cDNA fragment encoding an expansin gene (EXP) was isolated from Sinorhizobium meliloti-inoculated sweetclover root RNA by reverse-transcriptase polymerase chain reaction using degenerate primers, and a full-length sweetclover expansin sequence (MaEXP1) was obtained using 5' and 3' rapid amplification of cDNA end cloning. The predicted amino acid of the sweetclover expansin is highly conserved with the various alpha-expansins in the GenBank database. MaEXP1 contains a series of eight cysteines and four tryptophans that are conserved in the alpha-expansin protein family. Northern analysis and whole-mount in situ hybridization analyses indicate that MaEXP1 mRNA expression is enhanced in roots within hours after inoculation with S. meliloti and in nodules. Western and immunolocalization studies using a cucumber expansin antibody demonstrated that a cross-reacting protein accumulated in the expanding cells of the nodule. |
3,433 | 288 | 24223114 | Can zinc finger nucleases be used to combat disease? | An over expression APP model for anti-Alzheimer disease drug screening created by zinc finger nuclease technology. Zinc Finger Nucleases (ZFNs), famous for their ability to precisely and efficiently modify specific genomic loci, have been employed in numerous transgenic model organism and cell constructions. Here we employ the ZFNs technology, with homologous recombination (HR), to construct sequence-specific Amyloid Precursor Protein (APP) knock-in cells. With the use of ZFNs, we established APP knock in cell lines with gene-modification efficiencies of about 7%. We electroporated DNA fragment containing the promoter and the protein coding regions of the zinc finger nucleases into cells, instead of the plasmids, to avoid problems associated with off target homologous recombination, and adopted a pair of mutated FokI cleavage domains to reduce the toxic effects of the ZFNs on cell growth. Since over-expression of APP, or a subdomain of it, might lead to an immediately lethal effect, we used the Cre-LoxP System to regulate APP expression. Our genetically transformed cell lines, w5c1 and s12c8, showed detectable APP and Amyloid β (Aβ) production. The Swedish double mutation in the APP coding sequence enhanced APP and Aβ abundance. What is more, the activity of the three key secretases in Aβ formation could be modulated, indicating that these transgenic cells have potential for drug screening to modify amyloid metabolism in cells. Our transformed cells could readily be propagated in culture and should provide an excellent experimental medium for elucidating aspects of the molecular pathogenesis of Alzheimer's disease, especially those concerning the amyloidogenic pathways involving mutations in the APP coding sequence. The cellular models may also serve as a tool for deriving potentially useful therapeutic agents. |
3,447 | 289 | 17711494 | What is known about depression in acoustic neuroma patients? | Headaches after acoustic neuroma surgery. Headache and depression were studied in patients who had undergone operation for acoustic neuroma. A questionnaire with headache and Beck Depression Inventory scale were sent to 228 patients, of whom 192 (84%) responded. Preoperative headache was reported by 61 (32%) of the respondents (47 migraine and nine tension-type headache) and 122 (64%) respondents had postoperative headache (15 new migraine and four new tension-type headache). The new postoperative headache was chronic (>/=3 months) in 86% and continued at the time of the survey in 55% and presented typically as severe short-lasting attacks provoked by physical stress, bending or coughing. Non-steroidal anti-inflammatory drugs were effective in most cases. Depression (usually mild) occurred in 24% of the respondents, being significantly more common in prolonged postoperative headache patients. The operation doubled the prevalence of headache (from 32% to 64%). Headache after acoustic neuroma operation appears to be a specific subgroup of postcraniotomy headache. |
3,451 | 290 | 10932008 | Mutation of which gene is associated with Achondroplasia? | [Differentiation of achondroplasia and other similar genetic dwarfism by FGFR3 gene analysis]. OBJECTIVE: To study the gene mutation of Chinese patients with achondroplasia(ACH) and to set up a simple and rapid molecular diagnostic method to differentiate ACH from other similar genetic dwarfism. METHODS: The specific fragment of fibroblast growth factor receptor 3(FGFR3) transmembrane domain was amplified from dried blood spots of 21 patients with ACH and 6 suspicious patients with ACH by polymerase chain reaction, then mutation was screened and detected by restrictive enzyme analysis, single strand conformation polymorphism(SSCP) and denaturing gradient gel electrophoresis(DGGE). RESULTS: One out of 6 suspicious cases was ACH and 5 were pseudoachondroplasia(PSACH). Twenty-one out of 22 patients with ACH bore a G to A transition at nucleotide 1138 and 1 bore a G to C transversion at this same position. CONCLUSION: The nucleotide 1138 of FGFR3 gene is also the hotspot of mutation in Chinese patients with ACH. A simple and rapid molecular diagnostic method has been set up to differentiate ACH from other similar genetic dwarfism. |
3,460 | 291 | 18852131 | What is the mode of action of Hsp90 inhibitors? | Antitumor activity and molecular effects of the novel heat shock protein 90 inhibitor, IPI-504, in pancreatic cancer. Targeting Hsp90 is an attractive strategy for anticancer therapy because the diversity and relevance of biological processes are regulated by these proteins in most cancers. However, the role and mode of action of Hsp90 inhibitors in pancreatic cancer has not been studied. This study aimed to assess the antitumor activity of the Hsp90 inhibitor, IPI-504, in pancreatic cancer and to determine the biological effects of the agent. In vitro, we show that pharmacologic inhibition of Hsp90 by IPI-504 exerts antiproliferative effects in a panel of pancreatic cancer cells in a dose- and time-dependent manner. In pancreatic cancer xenografts obtained directly from patients with pancreas cancer, the agent resulted in a marked suppression of tumor growth. Although known Hsp90 client proteins were significantly modulated in IPI-504-treated cell line, no consistent alteration of these proteins was observed in vivo other than induction of Hsp70 expression in the treated xenografted tumors. Using a proteomic profiling analysis with isotope tags for relative and absolute quantitation labeling technique, we have identified 20 down-regulated proteins and 42 up-regulated proteins on IPI-504 treatment.tumor growth Identical changes were observed in the expression of the genes coding for these proteins in a subset of proteins including HSPA1B, LGALS3, CALM1, FAM84B, FDPS, GOLPH2, HBA1, HIST1H1C, HLA-B, and MARCKS. The majority of these proteins belong to the functional class of intracellular signal transduction, immune response, cell growth and maintenance, transport, and metabolism. In summary, we show that IPI-504 has potent antitumor activity in pancreatic cancer and identify potential pharmacologic targets using a proteomics and gene expression profiling. |
3,464 | 292 | 12865274 | Is RET the major gene involved in Hirschsprung disease? | Rescue of human RET gene expression by sodium butyrate: a novel powerful tool for molecular studies in Hirschsprung disease. BACKGROUND: The RET gene encodes a tyrosine kinase receptor involved in different human neurocristopathies, such as specific neuroendocrine tumours and Hirschsprung disease (HSCR). Gene expression is developmentally regulated and the RET transcript is undetectable in most adult cells, including lymphocytes. The impossibility of performing functional studies on RET mRNA has to date limited the detection and characterisation of an indefinite proportion of gene anomalies that cannot be identified by conventional DNA genomic screening in HSCR cases. AIMS: Development of a protocol suitable to activate RET expression in RET negative cell lines and therefore to investigate directly RET mRNA, extending the conventional gene mutation analysis to detection of splicing anomalies and impaired expression of the RET gene. METHODS: The effect of sodium butyrate (NaB), a histone deacetylase inhibitor, on rescuing RET expression was tested by one round of reverse transcription- polymerase chain reaction from total RNA of treated lymphoblasts from both HSCR patients and control individuals. RESULTS: Analysis of RET expression was possible by NaB treatment of RET negative cells, such as lymphoblasts. This treatment allowed us to detect impaired RET expression as well as a splicing defect in two HSCR patients previously believed to be devoid of any gene abnormality. CONCLUSIONS: The full application of the proposed protocol in most of the unexplained HSCR cases will allow us to establish the precise role of RET not only in causing but also in predisposing to HSCR pathogenesis. |
3,486 | 293 | 8568672 | Which type of lung cancer is the most strongly associated with Lambert-Eaton syndrome? | Inhibition of calcium currents and exocytosis by Lambert-Eaton syndrome antibodies in human lung cancer cells. 1. Human small-cell lung cancer (SCLC) cells are believed to express the antigens responsible for the production of pathological antibodies in the Lambert-Eaton syndrome (LES), a Ca2+ channel disorder in which quantal transmitter release from the motor nerve terminal is impaired. Whole-cell patch-clamp techniques were used to study the voltage-dependent Ca2+ channels expressed by H146 SCLC cells and the effects of LES antibodies on these channels. The types of Ca2+ channels were determined using biophysical properties and pharmacological sensitivity to several antagonists. 2. Whole-cell Ca2+ currents (ICa) in SCLC cells are sensitive to the dihydropyridine (DHP) nicardipine, omega-conotoxin GVIA (omega-CgTX GVIA) and omega-agatoxin IVA (omega-AgTX IVA). Nicardipine at 100 nM and 10 microM reduced ICa by 35 and 45% (n = 38 cells), respectively, while omega-CgTX GVIA (1 microM) inhibited ICa by 32% (n = 31). Application of omega-AgTX IVA at 50 and 100 nM to the cancer cells decreased ICa by 41 and 42%, respectively (n = 22). 3. Measurement of cell membrane capacitance (Cm) revealed that Ca(2+)-dependent exocytosis underlies the secretory activity of SCLC cells. Exocytosis, when induced by step depolarizing pulses and measured by increases in Cm, was markedly inhibited by nicardipine (10 microM) and omega-AgTX IVA (100 nM). In contrast, omega-CgTX GVIA (1 microM) was not as effective in altering increases in Cm. 4. From negative (-80 mV) and depolarized (-40 mV) holding potentials, both peak and plateau ICa were inhibited by the presence of LES antibodies (1 mg ml-1 IgG). LES serum also reduced depolarization-induced increases in Cm by 48% (n = 15). 5. To determine whether the LES antibodies are downregulating a specific type(s) of Ca2+ channel, nicardipine (10 microM), omega-CgTX GVIA (1 microM) or omega-AgTX IVA (100 nM) was applied to tumour cells that had been previously exposed to LES serum for 24 h. The most pronounced change was that omega-AgTX IVA was 38-84% less effective at reducing ICa after the IgG treatment. The effectiveness of nicardipine was diminished by 18% after incubation with the LES antibodies, whereas the omega-CgTX GVIA was seen to be more effective. These results suggest that LES IgG downregulates P-type Ca2+ channels and, possibly, to a lesser extent L-type channels. 6. In view of recent evidence that P-type Ca2+ channels mediate cholinergic transmitter release at the mammalian neuromuscular junction (NMJ), the expression of P-type Ca2+ channels in the SCLC cells and the reactivity of LES IgG with these channels support the hypothesis that P-type Ca2+ channels in these cancer cells may trigger the autoantibody production in this disorder. The antibodies so produced are implicated in the functional impairment of the Ca2+ channels characteristic of LES. |
3,517 | 294 | 12361237 | What distinguishes lantibiotics from antibiotics? | Combination of antibiotic mechanisms in lantibiotics. Recent studies on the mode of action have revealed exciting features of multiple activities of nisin and related lantibiotics making these peptides interesting model systems for the design of new antibiotics (Molec. Microbiol. 30 (1998) 317; Science 286 (1999) 2361; J. Biol. Chem. 276 (2001) 1772.). In contrast to other groups of antibiotic peptides, the lantibiotics display a substantial degree of specificity for particular components of bacterial membranes. Mersacidin and actagardine were shown to bind with high affinity to the lipid coupled peptidoglycan precursor, the so-called lipid II, which prevents the polymerisation of the cell wall monomers into a functional murein sacculus. The lantibiotics nisin and epidermin also bind tightly to this cell wall precursor; however, for these lantibiotics the binding of lipid II has two consequences. Like with mersacidin blocking of lipid II inhibits peptidoglycan biosynthesis; in addition, lipid II is used as a specific docking molecule for the formation of pores. This combination of lethal effects explains the potency of these peptides, which are active in nanomolar concentration. Other type-A lantibiotics are believed to also use docking molecules for pore formation, although identification of such membrane components has not yet been achieved. |
3,532 | 295 | 10439962 | List three major features of the CCFDN syndrome. | Congenital cataracts facial dysmorphism neuropathy (CCFDN) syndrome: a novel developmental disorder in Gypsies maps to 18qter. We have identified a novel developmental disorder with complex phenotypic characteristics involving primarily the nervous system, which appears to be common in a specific Gypsy group in Bulgaria. We propose to refer to the syndrome as congenital cataracts facial dysmorphism neuropathy (CCFDN). We have assigned the disease locus to the telomeric region of chromosome 18q. Linkage disequilibrium and highly conserved haplotypes suggest genetic homogeneity and founder effect. CCFDN co-localises with an EST which shows high homology to a conserved Drosophila gene involved in the regulation of nervous system development in vertebrates. |
3,544 | 296 | 21925040 | is intense physical activity associated with longevity ? | Significant variation of traditional markers of liver injury after a half-marathon run. BACKGROUND: While the promotion of health-related fitness is thereby widespread, less focus is currently being given on the biological influence that physical activity might exert on results of laboratory testing. As such, this study was undertaken to assess the kinetics of liver injury markers following physical exercise. DESIGN AND METHODS: Total and direct bilirubin as well as the activity of biochemical markers of liver injury including aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), gamma-glutamyl transpeptidase (GGT) and creatine kinase (CK), were measured before and after a half-marathon. RESULTS: Significant increases occurred for GGT, AST, LDH, CK, total and direct bilirubin immediately after the run. AST, LDH, CK, total and direct bilirubin were still increased 24h thereafter, whereas GGT decreased after 6h. None of the athletes exceed the upper reference limit for ALT, ALP and GGT, whereas significant variations were instead observed for LDH, AST, CK, total and direct bilirubin. CONCLUSIONS: Taken together, the results of our prospective investigation clearly attest that an acute bulk of aerobic physical exercise, such as a half-marathon, might produce significant changes in the activity of traditional biomarkers of liver injury, which should be carefully considered when investigating physically active individuals undergoing laboratory testing. |
3,562 | 297 | 24831536 | Are cyclophilins proteins that bind to prolines? | From chemical tools to clinical medicines: nonimmunosuppressive cyclophilin inhibitors derived from the cyclosporin and sanglifehrin scaffolds. The cyclophilins are widely expressed enzymes that catalyze the interconversion of the cis and trans peptide bonds of prolines. The immunosuppressive natural products cyclosporine A and sanglifehrin A inhibit the enzymatic activity of the cyclophilins. Chemical modification of both the cyclosporine and sanglifehrin scaffolds has produced many analogues that inhibit cyclophilins in vitro but have reduced immunosuppressive properties. Three nonimmunosuppressive cyclophilin inhibitors (alisporivir, SCY-635, and NIM811) have demonstrated clinical efficacy for the treatment of hepatitis C infection. Additional candidates are in various stages of preclinical development for the treatment of hepatitis C or myocardial reperfusion injury. Recent publications suggest that cyclophilin inhibitors may have utility for the treatment of diverse viral infections, inflammatory indications, and cancer. In this review, we document the structure-activity relationships of the nonimmunosuppressive cyclosporins and sanglifehrins in clinical and preclinical development. Aspects of the pharmacokinetic behavior and chemical biology of these drug candidates are also described. |
3,566 | 298 | 23169561 | Can a given genotype exhibit opposite fitness effects (beneficial and detrimental) within the same environment? | The basis of antagonistic pleiotropy in hfq mutations that have opposite effects on fitness at slow and fast growth rates. Mutations beneficial in one environment may cause costs in different environments, resulting in antagonistic pleiotropy. Here, we describe a novel form of antagonistic pleiotropy that operates even within the same environment, where benefits and deleterious effects exhibit themselves at different growth rates. The fitness of hfq mutations in Escherichia coli affecting the RNA chaperone involved in small-RNA regulation is remarkably sensitive to growth rate. E. coli populations evolving in chemostats under nutrient limitation acquired beneficial mutations in hfq during slow growth (0.1 h(-1)) but not in populations growing sixfold faster. Four identified hfq alleles from parallel populations were beneficial at 0.1 h(-1) and deleterious at 0.6 h(-1). The hfq mutations were beneficial, deleterious or neutral at an intermediate growth rate (0.5 h(-1)) and one changed from beneficial to deleterious within a 36 min difference in doubling time. The benefit of hfq mutations was due to the greater transport of limiting nutrient, which diminished at higher growth rates. The deleterious effects of hfq mutations at 0.6 h(-1) were less clear, with decreased viability a contributing factor. The results demonstrate distinct pleiotropy characteristics in the alleles of the same gene, probably because the altered residues in Hfq affected the regulation of expression of different genes in distinct ways. In addition, these results point to a source of variation in experimental measurement of the selective advantage of a mutation; estimates of fitness need to consider variation in growth rate impacting on the magnitude of the benefit of mutations and on their fitness distributions. |
3,569 | 299 | 18263876 | Has the protein SETMAR (Metnase) a transposase domain? | Human Pso4 is a metnase (SETMAR)-binding partner that regulates metnase function in DNA repair. Metnase, also known as SETMAR, is a SET and transposase fusion protein with an undefined role in mammalian DNA repair. The SET domain is responsible for histone lysine methyltransferase activity at histone 3 K4 and K36, whereas the transposase domain possesses 5'-terminal inverted repeat (TIR)-specific DNA binding, DNA looping, and DNA cleavage activities. Although the transposase domain is essential for Metnase function in DNA repair, it is not clear how a protein with sequence-specific DNA binding activity plays a role in DNA repair. Here, we show that human homolog of the ScPSO4/PRP19 (hPso4) forms a stable complex with Metnase on both TIR and non-TIR DNA. The transposase domain essential for Metnase-TIR interaction is not sufficient for its interaction with non-TIR DNA in the presence of hPso4. In vivo, hPso4 is induced and co-localized with Metnase following ionizing radiation treatment. Cells treated with hPso4-siRNA failed to show Metnase localization at DSB sites and Metnase-mediated stimulation of DNA end joining coupled to genomic integration, suggesting that hPso4 is necessary to bring Metnase to the DSB sites for its function(s) in DNA repair. |