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The HIV-1 Tat protein activates transcription from an upstream DNA-binding site: implications for Tat function. The Tat protein of human immunodeficiency virus type 1 (HIV-1) activates transcription following binding to nascent trans-activation response (TAR) RNA downstream of the transcription start site. Because Tat functions when bound to RNA, and in a position-dependent manner, it has been proposed that Tat works by a novel mechanism. Here, we perform a series of protein fusion experiments that reveal striking similarities between Tat and conventional cellular activators. Most significantly, we demonstrate that Tat can function when bound to upstream promoter DNA. This activity depends on a region within Tat that is also required for Tat to function when bound to TAR RNA. In contrast, the arginine-rich region of Tat, which is required for binding to TAR RNA, is dispensable for the function of DNA-bound Tat. When bound either to RNA or DNA Tat activity requires cooperation with promoter-bound cellular transcription factors. Finally, we show that Tat and a strong acidic activator stimulate transcription to comparable levels. On the basis of these and other results we suggest that Tat and acidic activators act on a similar step in the transcription process.

The implications for malaria vaccine programs if memory T cells from non-exposed humans can respond to malaria antigens. Although the goal of current candidate vaccines is to expand a population of malaria antigen-specific lymphocytes, accumulating evidence suggests that peripheral blood of adult humans contains significant numbers of malaria-specific T cells prior to any exposure to vaccine or actual infection. The reason why such naive humans are susceptible to malaria infection may thus relate not to inadequate T-cell surveillance but to some other factor--possibly lack of suitable splenic modification. It is possible that current vaccine programs are misdirected because these other factors are not being addressed. The possibility of an attenuated vaccine should be re-examined.

[Lacrimal duct intubation as an alternative to dacryocystorhinostomy]. A series of 52 patients, aged 60-85 and suffering from chronic obstruction of the nasolacrimal duct with no other complication of the lacrimal mechanism or of the eyelids (e.g. ectropium), were treated by means of silicon tube intubation instead of dacryocystorhinotomy. The tubes remained in place for 10-12 months and the patients were observed a 3-year postoperative period. In 37 cases (71%) the nasolacrimal duct remained patient after 3 years. In 7 cases, although the drainage was not opened, the patients ceased to show evidence of secretion of mucus or pus. We consider that intubation of the nasolacrimal duct is an alternative to dacryocystorhinotomy, but only if the patient knows that the tubes are to remain in place for a lengthy period of time. This does not disturb a cooperative patient since the tubes are essential and do not create any irritation. Furthermore, tears are partially eliminated around them and, thus, improvement of the symptoms is apparent from the first day onward.

Purification and partial sequence analysis of pp185, the major cellular substrate of the insulin receptor tyrosine kinase. Insulin stimulates the tyrosine phosphorylation of a 185-kDa putative cytosolic substrate protein (pp185) in diverse cell types. After intravenous insulin infusion into the live intact rat, pp185 and the 95-kDa insulin receptor beta-subunit were the major proteins that tyrosine phosphorylated in liver, skeletal muscle, and adipose tissue. Both proteins were maximally phosphorylated within 30 s, and both increased in phosphotyrosine content in parallel with increasing insulin dose. However, pp185 tyrosine phosphorylation was transient, with almost complete dephosphorylation within 2-3 min despite continued insulin stimulation. To identify pp185 directly, we purified pp185 from insulin-stimulated rat liver, using a denaturation-based extraction procedure that blocks endogenous protein phosphatases and thus allows a high yield, single step isolation of phosphotyrosyl proteins by anti-phosphotyrosine antibody immunoaffinity absorption. From 50 rat livers, 50-100 pmol of pp185 was isolated. Edman degradation of seven internal tryptic peptide fragments of pp185 yielded novel amino acid sequences, indicating that pp185 is a new protein. Antipeptide antibodies were raised which specifically recognize a single, 185-kDa insulin-stimulated phosphotyrosyl protein in liver, skeletal muscle, adipose tissue, and several cultured cell lines. These results indicate that pp185 is expressed in a variety of insulin-responsive tissues, is the major protein rapidly tyrosine phosphorylated under physiological conditions in the intact animal, and also provide a route for cloning the pp185 gene and elucidating the function of pp185 in insulin signal transduction.

[Amniotic fluid tests for fetal lung maturity (author's transl)]. Amniotic fluid specimens of 30 pregnant women were examined for the evaluation of the fetal lung maturity. Three assays were used in parallel: the determination of the lecithin concentration, the estimation of the lecithin/sphingomyelin ratio and the shake test. The results were compared together and with the fetal outcome. The shake test has proved to be sufficient for the exclusion of an immature lung. To avoid failure from false-negative results of the shake test an additional determination of the lecithin/sphingomyelin ratio is recommended, whenever clinical dates give rise to expect a mature lung. The determination of the lecithin concentration has no advantage compared to the lecithin/sphingomyelin ratio. Pathology as candida infection or anecephaly falsifies.

Host resistance mechanisms to Newcastle disease virus in immunodeficient chickens (38540). In order to assess the mechanisms of host resistance to Newcastle disease virus (NDV), the susceptibility of young adult normal, T cell deficient and agammaglobulinemic chickens to an avirulent live vaccine (Bl) and a mesogenic strain of NDV was studied. All animals, regardless of immunological status resisted the vaccine strain. Most normal birds resisted mesogenic NDV, HOWEVER T cell deficient birds were much more susceptible and agammaglobulinemic chickens were extremely susceptible. There was no difference in the kinetics and levels of hemmagglutination-inhibition activity of plasma between normal, control-irradiated and T cell deficient birds nor between dying and surviving birds. Agammaglobulinemic chickens could be partially protected against an otherwise lethal challenge following immunization with avirulent NDV, low doses of mesogenic NDV inoculated intranasally or im injection of beta-propriolactone inactivated NDV mixed in complete Freund's adjuvant. The possible mechanisms for this protection together with the relative roles of humoral, cell mediated and non-specific immunity are discussed.

[Constitution and obesity in adolescents (author's transl)]. Obesity was found in 18% of 475 adolescents of both sexes by subtraction of lean body weight from whole body weight. Severe obesity is more frequent in male while lower degrees are more often seen in female adolescents. Obese youths are not only fatter than lean ones: their lean body weight is also higher, shoulders, chest and hips are broader. Their weight at birth was higher than that of none-obese subjects. Their mothers more often classify themselves as "well developed", "stout" or "fat"; the same is true for the fathers of obese girls but not for the obese boys' fathers. The results are discussed in context with the new findings of adipose tissue hyperplasia. It is felt that hereditary constitution of an individuum is of great importance in the development of obesity.

Morphologic variations and aging in the atrioventricular conduction system of large breed dogs. The microscopic anatomy of the atrioventricular node, bundle of His, both bundle branches and surrounding fibrous cardiac skeleton was studied in 40 large breed dogs of various ages. In the AV conduction system of all dogs over five years of age there was an increase of fibrous connective tissue, an infiltration of adipose tissue, loss of conduction fibers and focal fibrosis extending from the central fibrous body. Fibrosis was seen in the summit of the interventricular septum posterior to the AV node in dogs of all ages. Chondroid metaplasia was consistently observed in the central fibrous body and the root of the aorta in large breed dogs, including ten Doberman Pinschers of all ages. This metaplasia varied from a few chondroblasts and chondrocytes to mature chondrocytes with mineralization. Bone formation was seen in eight dogs. These changes appeared in close approximation to the cardiac conduction system above the bundle of His. No degenerative changes were seen in the AV bundle. Approximately one-half of the large breed dogs five years of age and older had thickened medial and intima proliferation in the small coronary arterioles supplying the AV node. The results of this study suggest that the presence of cartilage and bone in the central fibrous body is a normal occurrence in large breed dogs at all ages.

Close relationship between mink influenza (H10N4) and concomitantly circulating avian influenza viruses. Strains of an influenza H10N4 virus have been isolated during an outbreak of a respiratory disease in mink on the south-east coast of Sweden. This was the first example of a disease in mammals caused by the H10 subtype. We compared the A/mink/Sweden/84 strain with two recent avian H10N4 isolates, one from fowl and another from a mallard, both isolated in Great Britain in 1985 as well as the prototype A/chicken/Germany/N/49 (H10N7). The comparison was carried out by genomic analysis of the strains by oligonucleotide fingerprinting and in bioassays on mink. The oligonucleotide fingerprint analysis revealed a high degree of genomic homology of around 98% between the viruses from mink, mallard and fowl. Only the recent avian isolates, that from the mallard and fowl could infect mink by contact, causing similar pathological and clinical signs and inducing seroconversion as did the mink virus. However, the susceptibility of mink to the fowl and mallard viruses by contact was less pronounced than that to the mink virus. Both the genomic homology and the similarities from the infectivity and pathogenicity studies between the mink virus and the recent avian isolates point to a direct invasion of the mink population by an avian H10N4 virus.

Fatal stroke and use of oral contraceptives: findings from a case-control study. A case-control study of women less than 40 years of age in England and Wales was performed to evaluate the risk of fatal stroke associated with the use of the newer, low-dose oral contraceptives. Included were 296 cases with subarachnoid hemorrhage, 105 cases with other hemorrhagic stroke, and 21 cases with occlusive stroke, all of which occurred during 1986-1988. Two living controls per case, matched for age and marital status, were chosen from the general practice lists. The power of the study was such that the minimum significant increased relative risk of subarachnoid hemorrhage associated with ever having used oral contraceptives that could have been detected with 90% certainty was 1.6; the equivalent value for occlusive stroke was 28.4. Relative risk was estimated by conditional logistic regression allowing for matching. The adjusted relative risk of subarachnoid hemorrhage associated with oral contraceptives was estimated to be 1.1 (95% confidence interval (CI) 0.6-1.9) for current use and 1.3 (95% CI 0.9-1.8) for ever use, while the equivalent relative risk of an occlusive stroke associated with ever use was 4.4 (95% CI 0.8-24.4). Oral contraceptive use may be associated with a small increase in the risk of subarachnoid hemorrhage. These data are consistent with a substantial increase in the risk of occlusive stroke associated with oral contraceptive use.

Nutritional care considerations of older Americans. The US Census Bureau's 1977 projection of the nation's population aged 65 and older by the year 2000 was 31.8 million. This paper addresses the projection that in the future a higher proportion of the population in the United States will be older persons. It is obvious that older Americans are living longer with an increased incidence of diseases such as diabetes, hypertension, cardiac problems, and obesity, requiring medical and nutritional care. This paper discusses commitment to provide quality services in terms of prescribing appropriate and functional therapeutic diets to meet the needs of older Americans. Two mechanisms are discussed that are effective tools for calculating diabetic diet prescriptions and weight reduction diets based on energy level and energy needs. Also discussed are the provision of assistance to meet the social support needs of old people such as food stamps, Meals-on-Wheels, and homemaker's service.

Modification of cardiovascular responses to histamine by dithiothreitol. 1 Histamine produced dose-dependent contractile responses on both isolated perfused ear arteries and aortic strips of the rabbit. These responses were blocked by mepyramine and potentiated by both metiamide and dithiothreitol. 2 In the presence of maximum potentiation by metiamide, dithiothreitol still potentiated the contractile response to histamine of both preparations. 3 In the presence of mepyramine, histamine produced dose-dependent reductions in the contractile response to noradrenaline. This vasodilator action of histamine was abolished by metiamide but was unaffected by dithiothreitol. 4 The vasodilator action of histamine on the human isolated perfused temporal artery and the positive inotropic effect of histamine on the isolated spontaneously beating atria of the rabbit were blocked by metiamide but unaffected by dithiothreitol. 5 It is concluded that the rabbit aorta, like the ear artery, contains both H1 and H2 histamine receptors and that dithiothreitol potentiates cardiovascular responses mediated by H1-receptors but not by H2-receptors.

Effect of hormones on pancreatic macromolecular transport. The role of subcellular organelles in the synthesis, transport, and secretion of pancreatic digestive proteins has been well documented. This study was designed to examine effects of pentagastrin, secretin, and acute and chronic administration of cholecystokinin-pancreozymin (CCK-PZ) on pancreatic macromolecular transport and secretion. Pooled rat pancreas slices were pulse-labeled with L-[14-C]phenylalanine and migration of 14-C-labeled proteins studied by "chase" incubation for 15, 30, 60, and 120 min. After in vitro incubation of control and drug-treated pancreatic slices, subcellular particles were isolated by differential centrifugation; Specific activity of radioactive labeled proteins was determined in subcellular fractions involved in transport and secretion of digestive proteins. These studies indicate that pentagastrin and acute and chronic stimulation with CCK-PZ did not alter the rate of transport of labeled proteins from ribosomes to the zymogen granules. Pentagastrin and CCK-PZ stimulated secretion of labeled proteins from the zymogen granules into the medium in the concentrations used as evidenced by significant increase in the amount of labeled proteins in the medium and significant decrease in the specific activity of the zymogen granule fractions after 60- and 120-min periods of incubation. Secretin did not alter the rate of transport or secretion of the pulse-labeled proteins.

Blood glucose control by direct islet innervation. Glucose tends to be elevated in situations of stress and an increase in plasma glucagon is an important cause. The rapidity of the glucagon rise in stress suggests a nervous mechanism. Electron microscopy has shown that the alpha and beta cells of the pancreas have, in fact, both an adrenergic and cholinergic innervation. Splanchnic-nerve stimulation has been shown in animals to cause a massive release of glucagon and marked inhibition of insulin. The glucagon response to hypoglycemia, on the other hand, appears to be significantly controlled by the parasympathetic system and, in man, is greatly attenuated after vagotomy. Thus there is a dual influence of the autonomic system on the islets of Langerhans, the sympathetic innervation elevating glucose in stress and the parasympathetic aiding glucose homeostasis.

Genetic differences in heat-induced tolerance to cadmium in cultured mouse embryos are not correlated with changes in a 68-kD heat shock protein. Heat-induced cross-tolerance to cadmium was investigated in two inbred strains of mice, BALB/c and SWV, using a whole embryo culture system. Embryos were exposed to a pretreatment of 5 min at 43 degrees C and subsequently to an embryotoxic concentration of cadmium, 1.75 microM. The two types of embryos responded differently to the heat pretreatment, as cross-tolerance was induced in SWV but not in BALB/c mice. In SWV embryos, prior exposure to 43 degrees C for 5 min essentially eliminated the negative effects of cadmium on embryonic development and growth. However, in BALB/c embryos, no protection was observed. The variation in development of cross-tolerance in embryos from the two strains of mice was not correlated with differences in the induction of a 68-kD heat-shock protein (hsp68). There was a rapid increase in this protein in both strains after the initial heat exposure but not excess induction in the SWV strain that developed tolerance. The induction of hsp68 is therefore not sufficient to elicit cross-tolerance, and other mechanisms are likely to be important in the protective response of the embryo.

[application of electromyography (EMG) in recognition of lumbo-sacral back pain]. Power spectra of electromyograms (EMG) of back muscles in the lumbo-sacral area were compared in two groups of subjects. In the first one EMGs were registered in 49 young, healthy, males working in standing posture. The recordings were carried out at rest, after application of a 20 kg load and at the onset of pain. In the second group 31 subjects of both sexes and different age, suffering from intense back pain of various etiology, were investigated and compared with a group of 15 healthy persons. In the first group the power level increased after the loading, and in 42 subjects it showed further rise when the pain appeared. In the second group the power level at the range of 25 to 400 Hz, at rest, was significantly higher in the back pain patients than in healthy subjects. The results are discussed from the point of view of their applicability for the diagnosis of back pain.

Subacute sclerosing panencephalitis and multiple sclerosis: in vitro measles immunity and sensitization to myelin basic protein. Three children with subacute sclerosing panencephalitis (SSPE), 12 patients with multiple sclerosis (MS) and 12 healthy persons were studied by the macrophage migration inhibition factor (MIF) assay with measles and rubella antigens and with myelin basic protein. For the SSPE patients the mean migration indexes +/- standard deviation were 44.1 +/- 10.9 for measles antigen, 38.7 +/- 12.3 for rubella antigen and 49.8 +/- 25.7 for myelin basic protein; for the MS patients the indexes were 103.0 +/- 10.6, 93.8 +/- 15.0 and 89.3 +/- 19.9; and for the healthy subjects the indexes were 68.8 +/- 22.6, 77.7 +/- 31.3 and 100.1 +/- 6.5. The results of this study showed increased cellular immunity to measles and rubella in SSPE patients as compared with healthy persons, and absence of immunity to measles in MS patients. Patients with MS showed hypersensitivity to myelin basic protein during clinical exacerbations that was not associated with changes in immunity to measles, whereas all SSPE patients showed a significant response regardless to stage of illness.

[Laparoscopic hysterectomy. Results in 44 cases]. Laparoscopic hysterectomy is a recent procedure. We present our preliminary results about 44 patients. In 77.3% of cases (34 patients) the operation was carried out completely by laparoscopy and 10 patients (22.7%) required conversion of the laparoscopy to a standard laparotomy. The indications for laparotomy were: hemostasis difficulties (6 cases); bladder injury (1 case); inability to expose the uterine pedicles and or the ureter (3 cases). Three post-operative complications occurred: one small bowel occlusion which was explored by laparoscopy, and two infection treated by antibiotics only. These preliminary results enable us: to affirm that laparoscopic hysterectomy is feasibility without an important risk of per and or post-operative complications. to specify the four situations in which laparoscopic surgery is particularly advantageous for hysterectomy: absence of genital prolapse; when uni or bilateral adnexectomy is required; previous past-history of abdomino-pelvic surgery, salpingitis, endometriosis ...; neoplastic pathologies (lymphadenectomy); to propose a laparoscopic hysterectomy classification.

FMRFamide-like immunoreactive nervus terminalis innervation to the pituitary in the catfish, Clarias batrachus (Linn.): demonstration by lesion and immunocytochemical techniques. Certain thick FMRFamide-like immunoreactive fibers arising from the ganglion cells of nervus terminalis in the olfactory bulb of Clarias batrachus can be traced centripetally through the medial olfactory tract, telencephalon, lateral preoptic area, tuberal area, and hypothalamohypophysial tract to the pituitary. Following 6 days of bilateral olfactory tract transection, the immunoreactivity in the thick fibers, caudal to the lesion site, was partially eliminated, whereas after 10 and 14 days, it was totally abolished in the processes en route to the pituitary. The results indicate a direct innervation of the pituitary gland by the FMRFamide-like peptide containing fibers of the nervus terminalis.

R 76713 and enantiomers: selective, nonsteroidal inhibitors of the cytochrome P450-dependent oestrogen synthesis. The triazole derivative, R 76713 and its enantiomers R 83839(-) and R 83842(+) are effective inhibitors of the aromatization of androstenedione. For human placental microsomes, the (+) enantiomer (R 83824) is about 1.9- and 32-times more active than the racemate (IC50 2.6 nM) and the (-) enantiomer, respectively. R 83842 is about 30- and 1029-times more active than 4-hydroxyandrostene-3,17-dione and aminoglutethimide. This potency might originate from its high affinity for the microsomal cytochrome P450 (P450). Indeed, R 83842, compared to R 76713 and R 83839, forms a more stable P450-drug complex. Difference spectral measurements indicate that the triazole nitrogen N-4 coordinates to the haem iron. The reversed type 1 spectral changes suggest that R 76713 is able to displace the substrate from its binding place and the stable complex formed in particular with the (+) enantiomer suggests that its N-1-substituent occupies a lipophilic region of the apoprotein moiety. Kinetic analysis implies that there is a competitive part in the inhibition of the human placental aromatase by R 76713. The Ki values for R 76713, R 83842 and R 83839 are 1.3 nM, 0.7 nM and 18 nM, respectively. These results are indicative of stereospecificity for binding. Up to 10 microM, R 76713 and its enantiomers have no statistically significant effect on the regio- and stereoselective oxidations of testosterone in male rat liver microsomes. All three compounds have no effect on the P450-dependent cholesterol synthesis, cholesterol side-chain cleavage and 7 alpha-hydroxylation and 21-hydroxylase. At 10 microM, R 76713 has a slight effect on the bovine adrenal 11 beta-hydroxylase. This effect originates mainly from R 83839, the less potent aromatase inhibitor. On the other hand, the inhibition of the 17,20-lyase of rat testis observed at concentrations greater than or equal to 0.5 microM, originates rather from R 83842. However, 50% inhibition is only achieved at 1.8 microM R 83842, i.e. at a concentration about 1300-times higher than that needed to reach 50% inhibition of the human placental aromatase.

Chemical and biological characterization of an active substance of the human placenta. Acetic acid extracts of human term placenta have been fractionated by pH and salt precipitations and by exclusion chromatography on a Sephadex G-75 column. A partially purified fraction (F-II) possessing uterotropic activity in immature and young mice was obtained. This active fraction was submitted to the action of protein denaturating agents (heat, 8 M urea) and of specific proteolytic enzymes (trypsin, alpha-chymotrypsin and pronase). These treatments completely destroy the uterotropic activity showing that the active substance is of protein nature. The administration of F-II to spayed mice did not produce any increase in their uterine weight suggesting that the uterotropic activity would be due to stimulation of the female gonad.

Patient-initiated rapid atrial pacing to manage supraventricular tachycardia. Patient-controlled rapid atrial pacing was used to manage 12 cases of recurrent supraventricular tachycardia refractory to drug therapy. The pacing system consists of an implanted receiver-lead system and an external patient-activated transmitter. In each case, brief periods (5 to 20 seconds) of rapid atrial pacing were effective in terminating the supraventricular tachycardia and resulted in a return to normal sinus rhythm. In three patients, occasional transient episodes of atrial flutter or atrial fibrillation preceded a spontaneous return to normal sinus rhythm. The pacing system was removed in one patient 13 months postoperatively because of persistent pericarditis; one patient died of an unrelated cerebral hemorrhage 13 months postoperatively. Successful management of supraventricular tachycardia has been maintained in the 10 remaining patients for 15 to 36 months (average 26.4). In more than 6,000 patient applications of rapid atrial pacing, there has been only one failure to convert the tachycardia. Successful application of permanent rapid atrial pacing requires (1) prescreening of patients with temporary external rapid atrial pacing to verify susceptibility to conversion of supraventricular tachycardia and absence of anomalous conduction pathways that may permit conduction of rapid pacing rates to the ventricles, and (2) assessment of the patient's ability to use the transmitter properly.

Relationship of a T-lymphocyte marker to phase of cell cycle and morphology of leukemic cells. Spontaneous rosette formation with sheep erythrocytes (SRBC) was studied in the peripheral blood and bone marrow lymphoid cells from a patient whose leukemic cells appeared to be T-lymphocytes. Simultaneous morphological examination of the peripheral blood white cells indicated that they consisted of 21% lymphoblast; 26% prolymphocytes and 48% mature lymphocytes. The distribution of bone marrow cells within the cell cycle was determined by flow microfluorometry and 7 hours after treatment with vincristine consisted of 69% in G1, 21% in S, and 9% in mitosis. Since virtually all the cells both in marrow and blood formed rosettes with SRBC this implies that the expression of this T cell marker is independent both of the morphological appearance of these cells and their position within the cell cycle.

The cellular basis of bone turnover and bone loss: a rebuttal of the osteocytic resorption--bone flow theory. There is now sufficient evidence to conclude that the osteocytic resorption--bone flow theory of bone turnove is untenable. According to this theory bone is resorbed not from the surface by osteoclasts but from within by osteocytes, towards which bone flows through tissue space away from bone forming surfaces. The need to invoke resorption by osteocytes stems from the belief that too few osteoclasts are present to account for normal bone resoption, a belief which reflects unawareness of the enormous capacity of the osteoclast and the rapidity of its advance. The belief that osteocytes resorb substantial amounts of bone rests on invalid conclusions from indirect techniques, various artifacts of specimen processing and unawareness of the microscopic characteristics of woven bone. Osteocytes enlarge their lacunae by resorbing bone only as a prelude to resorption from the surface, the osteocyte and osteoclast working together as a resorbing unit. The belief that bone can flow is incompatible both with the physical properties of bone and with a substantial body of evidence relating to Haversian remodelling; the experimental data purporting to demonstrate such flow can all be explained by conventional concepts of bone turnover.

Postmortem neopterin concentrations: comparison of diagnoses with and without cellular immunological background. Increased neopterin levels in urine and serum of living humans indicate an activation of the cellular immune system. We investigated 119 urine and 48 serum samples from 129 corpses taken at necropsy; 29 cases with a background of cellular immune activation were compared to 100 corpses with no such indication. Our investigations show the feasibility of postmortem neopterin measurements. However, different kinetics of serum and urine concentrations after death were observed. In addition, the data show that urine and serum neopterin concentrations were significantly higher when cellular immunological abnormalities were present when compared to the control group and to living healthy controls. The findings suggest, that increased postmortem urine neopterin concentrations in necropsy indicate pathological processes linked with cellular immune activation.

Differential diagnosis of limb-girdle muscular dystrophy and spinal muscular atrophy. Neuromuscular biopsies from 18 patients with proximal muscle weakness were classified electromyographically as myopathy (11 cases), denervation (3 cases), or inconclusive (4 cases). Myopathic changes of muscle fibers occurred in all biopsies. Small angular dark fibers were observed in nine biopsies, and small-group atrophy in four biopsies from the three above-mentioned groups. Two biopsies classified as denervation showed large-group atrophy. Terminal innervation ratio (TIR) was increased only in the three cases classified as denervation and in one inconclusive case. TIR, which is more closely correlated with electromyographic (EMG) results than are muscle fiber changes, may help differentiate spinal muscular atrophy from limb-girdle muscular dystrophy.

Muscle stretch used as conditioning stimulus for assessing a reciprocal inhibition. The disynaptic Ia-alpha inhibition between the tibialis anterior and the soleus muscles is now well known. This neuronal organization has been established thanks to the analysis of the Hoffmann reflex (H reflex) changes following an electrical stimulation of the antagonist muscle nerve. In some cases, anatomical constraints impede the use of this classical technique for assessing a reciprocal Ia inhibition between muscles. Furthermore, an electrical stimulus solicits the primary spindle afferents in conditions which are very different from their natural stimulus: the muscle stretch. Thus we have undertaken to analyse the changes of a soleus H reflex following a rapid stretch of the ankle dorsiflexors and therefore of their prime-mover: the tibialis anterior. The mechanical perturbations were imposed with a strong initial acceleration and a limited angular displacement thanks to an original device including electromagnet and spring. This technique, derivated from the quick release technique, was applied on relaxed muscles to avoid a co-contraction phenomenon. 45 to 50 ms after the initiation of the mechanical perturbation an early reflex response was observed on the stretched tibialis anterior. The area of this first reflex response was related to the initial acceleration of the passive dorsiflexion. Several arguments are presented in favour of the myotatic origin of this reflex component. The passive dorsiflexion used as a conditioning stimulus led to a strong and longlasting inhibition of the test soleus H reflex. The early inhibition of the soleus H reflex was observed only about 18 ms after the conditioning stimulus.(ABSTRACT TRUNCATED AT 250 WORDS)

Process chemicals in the oil and gas industry: potential occupational hazards. Numerous chemicals are used in various processes of the oil and gas industry: drilling, cementing, completion, stimulation, and production. The number and the complexity of composition of process chemicals has increased greatly over the last three decades. The occupational hazards of exposure to these agents has received little attention. We reviewed the various processes in the industry, the type of chemicals used in each process, and some of their characteristics. We placed emphasis on those for which significant toxicity has been established or is suspected, and those for which there is incomplete information on their chemistry and health hazards. This report is intended to form a basis for a more complete survey of the process chemicals, and to draw attention to the possibilities for toxic exposure resulting from use of these agents in the oil and gas industry. The ultimate objective is to promote the safe use of these agents in the industry.

Malate dehydrogenase, circular dichroism difference spectra of porcine heart mitochondrial and supernatant enzymes, binary enzyme-coenzyme, and ternary enzyme-coenzyme-substrate analog complexes. Circular dichroism spectra and circular dichroism difference spectra, generated when porcine heart mitochondrial and supernatant malate dehydrogenase bind coenzymes or when enzyme dihydroincotinamide nucleotide binary complexes bind substrate analogs, are presented. No significant changes are observed in protein chromophores in the 200- to 240-nm spectral range indicating that there is apparently little or no perturbation of the alpha helix or peptide backbone when binary or ternary complexes are formed. Quite different spectral perturbances occur in the two enzymes with reduced coenzyme binding as well as with substrate-analog binding by enzyme-reduced coenzyme binding. Comparison of spectral perturbations in both enzymes with oxidized or reduced coenzyme binding suggests that the dihydronicotinamide moiety of the coenzyme interacts with or perturbs indirectly the environment of aromatic amino acid residues. Reduced coenzyme binding apparently perturbs tyrosine residues in both mitochondrial malate dehydrogenase and lactic dehydrogenase. Reduced coenzyme binding perturbs tyrosine and tryptophan residues in supernatant malate dehydrogenase. The number of reduced coenzyme binding sites was determined to be two per 70,000 daltons in the mitochondrial enzyme, and the reduced coenzyme dissociation constants, determined through the change in ellipticity at 260 nm, with dihydronicotinamide adenine dinucleotide binding, were found to be good agreement with published values (Holbrook, J. J., and Wolfe, R. G. (1972) Biochemistry 11, 2499-2502) obtained through fluorescence-binding studies and indicate no apparent extra coenzyme binding sites. When D-malate forms a ternary complex with malate dehydrogenase-reduced coenzyme complexes, perturbation of both adenine and dihydronicotinamide chromophores is evident. L-Malate binding, however, apparently produces only a perturbation of the adenine chromophore in such complexes. Since the coenzyme has been found to bind in an open conformation on the surface of the enzyme and the substrate analogs bind at or very near the dihydronicotinamide moiety binding site, protein conformational changes are implicated during ternary complex formation with D-malate which can effect the adenine chromophore at some distance from the substrate binding site.

Expression of T cell receptor V gamma 5 in the adult thymus of irradiated mice after transplantation with fetal liver cells. T cell receptor (TcR) gamma/delta displays limited diversity and its diversity is distinct in different stages of ontogeny and in different anatomical sites. The V gamma 5 and V delta 1 gene products are preferentially expressed on the early fetal thymocytes and on Thy-1+ dendritic epidermal cells, whereas the V gamma 4 and V delta 5 gene products are abundantly expressed on the adult thymocytes. To elucidate whether the developmentally ordered appearance of thymocytes expressing TcR gamma/delta is dependent on the source of T cell precursors or is controlled by the thymic environment where T cells develop, we compared the expression of V gamma 5 on the early-appearing thymocytes between irradiated mice after transplantation with fetal liver (FL) cells and those after transplantation with bone marrow (BM) cells. Sequential appearance of thymocyte subpopulations was observed in the thymus of radiation FL chimeras similar to that seen in radiation BM chimeras. A substantial number of thymocytes bearing V gamma 5 appeared in the thymus at the early stage of radiation FL chimeras, whereas few, if any, of such V gamma 5-bearing thymocytes were detected in the thymus at any stage of radiation BM chimeras. These results suggested that the ordered expression of V gamma repertoire may depend on the origin of the T cell precursors but not on the thymic environment.

Analysis of the Rhodobacter capsulatus puc operon: the pucC gene plays a central role in the regulation of LHII (B800-850 complex) expression. Formation of the light harvesting complex B800-850 (LHII) of Rhodobacter capsulatus requires the expression of more than the three known genes specific for that complex (pucA, pucB and pucE) encoding the alpha, beta and gamma subunits of LHII, respectively. In this work evidence is presented that the product of the gene pucC, which is located downstream from pucA, is essential for high-level transcription of the pucBACDE operon and formation of LHII. Plasmids were constructed containing deletions in one or several puc genes and transferred to a pucC::Tn5 mutant in which the puc operon is not expressed. It was found that the LHII- phenotype of the mutant was due to the missing PucC protein and that all known puc genes are located in one operon. To dissect the pucC, pucD and pucE genes from pucB and pucA and independently regulate them, they were placed under control of the nifHDK promoter. Only under nitrogen-fixing growth conditions was the LHII- pucC::Tn5 mutant complemented by this construction. It is concluded that expression of pucC is essential for formation of the LHII complex in R.capsulatus. Analysis of the pucD and pucE genes led to the conclusion that the products of these genes stabilize the B800-850 complex.

IL-4 plays a dominant role in the differential development of Tho into Th1 and Th2 cells. We have analyzed the evolution of the pattern of lymphokine secretion by Th cell lines specific for either the synthetic terpolymer Glu60Ala30Tyr10 (GAT) or killed bacillus Calmette Guérin. When cultured in the presence of exogenous rIL-2 as a growth factor, GAT-specific Th cell lines secreted mainly IL-4, whereas bacillus Calmette Guérin-specific lines produced predominantly IL-2. However, culturing in the presence of rIL-4 or of anti-IL-4 mAb and rIL-2 led to the establishment of Th2-like and Th1-like lines, respectively, regardless of their Ag specificity. Inasmuch as we show that the proliferative response of mature Th1 and Th2 cells was identical in the presence of IL-4, these results indicate that IL-4 influences the development of Th cell subsets. To understand the mode of IL-4 action, we isolated immature GAT-specific Tho clones able to secrete IL-2 and IL-4. Two types of Tho cells were isolated: ThoA cells that secreted IL-2 and IL-4, but not IFN-gamma, and ThoB cells that secreted IL-2, IL-4, and IFN-gamma. We show for the first time that such cells are indeed Th precursors able to differentiate into Th1 or Th2 cells. We demonstrate that IL-4 positively and negatively controls the differentiation of Tho cells into Th2 and Th1 cells, respectively. When cultured in rIL-4, Tho cells stop secreting IL-2 and IFN-gamma, but maintain IL-4 secretion. Moreover, endogenous IL-4 produced by Tho cells has similar effects: when cultured in rIL-2 alone, Tho cells either keep their immature phenotype or become Th2 cells, but do not become Th1 cells. In contrast, neutralization of secreted IL-4 completely prevents the differentiation of Tho into Th2 cells, but permits the development of Th1 cells. The presence of exogenous IFN-gamma does not affect the development of Tho into Th1 and Th2 cells, because it does not modify either mode of IL-4 action. However, it influences the ratio between the two types of Tho cells: when IL-4 is neutralized, added IFN-gamma can induce IFN-gamma secretion by ThoA cells and thereby facilitate their passage into ThoB cells. Taken together, our results demonstrate that IL-4, in addition to mediating T cell growth, is a principal factor that controls the differential development of Tho cells into Th1 and Th2 cells.

PETSIM: Monte Carlo simulation of all sensitivity and resolution parameters of cylindrical positron imaging systems. Monte Carlo simulation techniques are applied to track the annihilation photons from positron decay, and store the photon histories. Reasonably realistic models of the isotope distribution in the brain and heart during typical PET studies, as well as the traditional phantoms used for measuring PET scanner performance can be built out of up to 10 hollow or solid cylinders. Separate programs model the source distribution and its attenuation characteristics, the collimators and the detectors. These modules are connected by compact gamma history files which are stored on disc or tape. Over 50 million gamma ray histories can be saved on a 1 Gbyte disc, representing the decay of several billion atoms. This allows for good precision even for single thin slices in scanners with wide axial acceptance. The simulation results include spectrum analysis, sensitivity to true coincident events, scattered coincident and single rays, and the effects on these parameters of detector dead time. The storage of intermediate results on tape reduces simulation time, since most common source geometries need be generated only once. The sensitivities in multi-slice systems are presented as matrices of coincident crystal planes. The matrix shows the true count sensitivity and the scatter fraction together for each valid combination of planes. This presentation is very useful for assessing the effects of various degrees of inter-plane collimation. The spatial resolution analysis includes the effects of positron range, non-collinearity of the gamma rays, multiple interaction within the detectors, and the effects of quantization into single crystals in multiple-crystal block detectors. Each of these effects can be turned on or off without repeating the simulation. Both in-plane and axial resolutions are calculated as a function of location of the positron-emitting nucleus and the angle of incidence of gamma rays on the crystals. Single crystals, blocks and crystals with depth of interaction encoding can be specified, as can the method of backprojection (planar, or 3D), so that the detector geometry can be optimized.

Presence of transforming growth factor-beta and their selective cellular localization in human ovarian tissue of various reproductive stages. Immunohistochemical studies were performed using specific polyclonal antibodies to transforming growth factor (TGF)-beta 1 and TGF-beta 2 to determine their presence and cellular localization in human ovarian tissues of various reproductive states. In the small ovarian follicles, the immunostaining for TGF-beta 1 was present in oocytes, follicle cells, and granulosa and theca cell layers. The level of immunostaining associated with granulosa and theca cell layers intensified as the size of the follicles increased. In the luteal tissue, both the small and large luteal cells immunostained for TGF-beta 1 and their intensities were similar to theca and granulosa cell layers, respectively. The patterns of immunostaining were similar in early (days 14-19), mid (days 22-25), and late (days 26-29) luteal phases; however, the intensity was highest at mid and decreased at late luteal phase. Corpus albicans showed a very weak immunostaining for TGF-beta 1, whereas ectopic pregnancy small luteal cells immunostained relatively intensely. The ovarian stromal, luteal tissue fibroblasts, and arterioles endothelial and smooth muscle cells were also immunostained for TGF-beta 1. The immunostaining of the ovarian tissues for TGF-beta 2 indicated that the theca cell layers were the exclusive cells in the follicles with intense immunostaining, which increased in the larger follicles. A low immunostaining was also observed in granulosa cell of the large follicles. In the luteal tissues, only small luteal cells showed intense immunostaining for TGF-beta 2, which was similar in intensity to that in the theca cells; however, the large luteal cells showed a low level of immunostaining at midluteal phase. The small luteal cells in corpus albicans and ectopic pregnancy luteal tissues retained their immunostaining for TGF-beta 2, but with lower intensity. Endothelial and smooth muscle cells of arterioles also immunostained for TGF-beta 2, but not ovarian stromal cells. Atretic follicles showed very low or no detectable immunostaining for TGF-beta 1 or TGF-beta 2. The results of present studies show that human ovarian tissue at all the reproductive states locally produces TGF-beta 1 and TGF-beta 2, and although TGF-beta 1 is present in most major ovarian cell types, TGF-beta 2 is only produced by theca cells in the follicles and small luteal cells in luteal tissues.

Effect of the host specific treatment in the phagocytosis of Trypanosoma cruzi blood forms by mouse peritoneal macrophages. Single doses of drugs active against Trypanosoma cruzi (megazol, nifurtimox and benznidazole) induce a rapid clearance of the blood parasites in experimentally infected mice. Furthermore, the in vitro phagocytosis and intracellular destruction by mouse peritoneal macrophage of blood forms collected from the treated animals is strongly enhanced as compared with parasites from untreated controls. The uptake of the blood forms by macrophages is significantly higher with megazol than with benznidazole and nifurtimox, a finding that concurs with data showing that megazol is also the most active compound in the living host. The possibility that macrophages participate in a synergic effect between the host immune response and chemotherapeutic effect is discussed.

Effect of environmental complexity on size of the superior colliculus. The present study examined effects of environmental complexity on the size of the superior colliculus, a subcortical structure involved in visuomotor functions. Long-Evans hooded rats raised together in a complex environment for 48 weeks were compared with their littermates housed in individual cages. The depth and area of the superficial gray layer of the superior colliculus were about 5-6% greater in the group from the complex environment, while the deeper layers of the superior colliculus showed no significant differences. The magnitude of the differences approached those reported for the neocortex, which has been considered to be distinctive in its morphological responsiveness to differential environmental complexity. The findings also extend previous observations that visual deprivation leads to shrinkage of the superficial gray layer and indicate that the morphology of this subcortical visual area is responsive to varying degrees of environmental stimulation.

[Fibrinolysis in several organs following splenectomy in animals]. Spleenectomy was found to have a disturbing effect on the anticoagulating system (ACS) function and to elicit changes of the fibrinolytic activity in tissues of some organs. At the greatest ACS suppression, on the 7th day after spleenectomy, the animals had a decreased total fibrinolytic activity (TFA) in extracts from the liver and lungs, while the activity was utterly absent in extracts from the heart. By the end of the restoration period of ACS function, on the 21st day after the surgery, in experimental animals no fibrinolysis was revealed in the extract from the myocardium, neither the unfermentative fibrinolysis (UF) was observed in extracts from the liver and lungs. Simultaneously a considerable fibrinolytic activity occurred in the tissues of kidneys and thymus, mainly on account of UF. Evidently, after spleenectomy the biosynthesis and accumulation of agents exerting unfermentative fibrinolytic activity is transferred from some organs to others.

The future of psychiatry: psychiatrists of the future. The authors' goal was to examine the changing demographic trends in psychiatry manpower. These changes have important implications for the practice of the profession in the future. Each year, the APA Office of Membership, in collaboration with the American Association of Directors of Psychiatric Residency Training, conducts a census of all residents in psychiatry. A survey instrument is sent to the director of residency training in each U.S. program accredited by the Accreditation Council for Graduate Medical Education. Using data from this survey and from the American Medical Association, the authors conducted a study of the changes in the number of psychiatric residents over the last decade, particularly the increases in the number and percentage of women in medicine and psychiatry. They found that the number of psychiatric residents has grown from 4,674 in academic year 1978-1979 to 5,829 in 1987-1988, an increase of 25%. The percentage of women has increased from 32% of all psychiatric residents in 1978-1979 to 41% in 1987-1988. The largest proportions of female physicians and psychiatrists were found in the age groups younger than 35. Previously documented gender differences that affect practice patterns and career opportunities may very well change as a function of the increasing representation of women in the profession of psychiatry, and these changes need to be taken into account in planning for future patient care and research needs.

Significance of HLA antigens and the mixed lymphocyte reaction in psoriasis. Human Major Histocompatibility (HLA) complex antigens B13, BW16, BW17, CW6 and D-MA are increased in frequency in patients with psoriasis. Of these, the strongest association is with HLA-CW6 and D-MA, with a relative risk of 10.4. Since no strong association with any HLA-A locus antigen is seen, it seems likely that the disease susceptibility gene for psoriasis lies close to the HLA-D locus, which is defined by the use of the mixed lymphocyte reaction (MLR). In the mouse, the Immune response (Ir) genes are found in the MLR region and it is thought that Ia antigens lie at a corresponding location in man. Recently, we have demonstrated that human epidermal cells cause stimulation in the mixed lymphocyte reaction. Lymphocyte antigens which stimulate in this reaction are known to be products of HLA genes and anti-HLA-D sera block stimulation by epidermal cells. It is possible that these antigens may be involved in the regulation of cell--cell communication. Psoriasis is a disease characterized by epidermal hyperproliferation. It is possible, therefore, that an HLA-linked deficiency of recognition between epidermal cells exists in patients with psoriasis and that this defect allows abnormal cellular proliferation to occur.

Contrasting effects of nitrofurans on plasma corticosterone in chickens following administration as a bolus or diet additive. Administration of furazolidone as a bolus dose (8-500 mg/kg), produced a decrease in plasma corticosterone in chickens. In contrast, addition of furazolidone or furaltadone to the diet (0.04% or above, 10 days), increased plasma corticosterone. Pre-treatment with a 200-mg/kg bolus of furazolidone or furaltadone did not affect pentobarbitone anaesthesia time in the birds. In chickens pre-treated with a nitrofuran in the diet, however, pentobarbitone anaesthesia time was significantly less than that in controls. Furaltadone in the diet, produced significant increases in the amount of cytochrome P-450 and the activity of aniline hydroxylase in the liver microsomes. It is suggested that nitrofurans given in the diet stimulated corticosterone biosynthesis in the adrenal glands and induced mixed-function oxidase activity in the liver. Nitrofurans given as a bolus did not produce these effects. Furazolidone (200 mg/kg) produced severe anorexia, which lasted 2 days in T-line birds. The anorexia seemed to be associated with tissue damage in the birds rather than the ensuing adrenal cortical insufficiency.

Induction of HLA class II molecules on human T cells: relationship to immunoregulation and the pathogenesis of AIDS. Human T cells express HLA class II molecules upon activation. The factors that regulate the induction of expression of these molecules are for the most part unknown. Here we report preliminary results indicating that tumor necrosis factor-alpha (TNF-alpha) regulates the induction of cell-surface HLA-DR, DO, and DP molecules in human T cells stimulated with PHA. In contrast, recombinant interferon-gamma (rIFN-gamma), recombinant interleukin-1 alpha (rIL-1 alpha), or rIL-4 appear to have no effect on class II expression. The role of class II molecules on activated T cells is discussed in relationship to immunoregulation and the progression of HIV infection. Three non-mutually exclusive hypotheses are discussed. In the first hypothesis, we consider the role of these class II molecules in antigen presentation of endogenously synthesized HIV envelope by CD4+ cells. The second is a clonal inactivation of virus-specific helper T cells that might occur as a consequence of a direct T cell to T cell interaction and a bypass of the "accessory signal" normally delivered by antigen-presenting cells such as macrophages. The third is a molecular mimicry between HIV envelope proteins and HLA class II molecules, which may lead to the development of autoimmunity against CD4+ T-cell-expressing class II molecules.

A computer-based biomechanical analysis of the three-dimensional motion of cementless hip prostheses. A computer-based mathematical technique was developed to measure and completely describe the migration and micromotion of a femoral hip prosthesis relative to the femur. This technique utilized the mechanics of rigid-body motion analysis and apparatus of seven linear displacement transducers to measure and describe the complete three-dimensional motion of the prosthesis during cyclic loading. Computer acquisition of the data and custom analysis software allowed one to calculate the magnitude and direction of the motion of any point of interest on the prostheses from information about the motion of two points on the device. The data were also used to replay the tests using a computer animation technique, which allowed a magnified view of the three-dimensional motion of the prosthesis. This paper describes the mathematical development of the rigid-body motion analysis, the experimental method and apparatus for data collection, the technique used to animate the motion, the sources of error and the effect of the assumptions (rigid bodies) on the results. Selected results of individual test runs of uncemented and cemented prostheses are presented to demonstrate the efficacy of the method. The combined effect of the vibration and electrical noise resulted in a resolution of the system of about 3-5 microns motion for each transducer. Deformation effects appear to contribute about 3-15 microns to the measurement error. This measurement and analysis technique is a very sensitive and powerful means of assessing the effects of different design parameters on the migration and micromotion of total joint prostheses and can be applied to any other case (knee, dental implant) where three-dimensional relative motion between two bodies is important.

Effect of carbamoyl phosphate on nitrogenase in Anabaena cylindrica Lemm. Carbamoyl phosphate inhibited acetylene reduction by whole cells and cell-free extracts of Anabaena cylindrica. Higher levels of both endogenous carbamoyl phosphate and carbamoyl phosphate synthase activity were present in NH4+-grown cells (in which acetylene reduction was absent) than in N2-grown cells (in which acetylene reduction was present). However, inhibition of acetylene reduction was observed also with cyanate, the main initial decomposition product under the conditions used. It is concluded that carbamoyl phosphate or one of its metabolites may act as a physiological regulator of both nitrogenase activity and synthesis, but caution must be used in interpreting effects observed several hours after the addition of carbamoyl phosphate, because the effects may be due to cyanate.

[A change in the puff spectrum during development of Drosophila virilis]. The puff spectrum has been studied in the salivary gland chromosomes of D. virilis from 48 hrs of the 3rd larval until the gland lysis. 142 puffs were observed in the D. virilis genome. Among them, 43% were observed at all developmental stages and other puffs were unstable: 47.1% appear at a certain stage and degrade or remain until the gland lysis; 9.9% are characterized by the "pulse" activity, i.e. they appear at a certain stage, degrade and reappear. The number of newly appeared puffs exceeds that of fully degraded ones, i.e. the number of puffs during the gland development until its lysis increases constantly. At the stage of puparium formation, sexual differences in the puff length were found: puffs were longer in males than in females.

Familial chronic recurrent pancreatitis in identical twins. Case report and review of the literature. Familial presentation of chronic recurrent pancreatitis in childhood is rare. The etiology of this illness is obscure, and its hereditary properties are not well defined. Simultaneous occurrence of chronic recurrent pancreatitis in identical twins with the same clinical presentation and similar typical pancreatographic abnormalities is exceptional. Twin sisters, aged 9 years, were admitted to the hospital because of recurrent attacks of pancreatitis. Ultrasound examination revealed an enlarged irregular pancreatic duct in both girls, and endoscopic retrograde cholangiopancreatography showed a distorted duct with multiple strictures and dilatations similar to a "chain of lakes" pattern. Both patients underwent longitudinal pancreatojejunostomy within a month. The therapeutic regimen and preoperative and surgical treatment of such patients are discussed, as is the optimal timing of intervention.

Parvalbumin and calbindin immunoreactivity in the cerebral cortex of the hedgehog (Erinaceus europaeus). To investigate the morphology and distribution of nonpyramidal neurons in the brain of insectivores, parvalbumin and calbindin 28 kDa immunoreactivity was examined in the cerebral cortex of the hedgehog (Erinaceus europaeus). Parvalbumin-immunoreactive cells were found in all layers of the isocortex, but in contrast to other mammals, a laminar organisation or specific regional distribution was not seen. Characteristic parvalbumin-immunoreactive neurons were multipolar cells with large ascending and descending dendrites extending throughout several layers. Calbindin-immunoreactive neurons were similar to those found in other species, although appearing in smaller numbers than in the cerebral cortex of more advanced mammals. The morphology and distribution of parvalbumin- and calbindin-immunoreactive cells in the piriform and entorhinal cortices were similar in hedgehogs and rodents. Parvalbumin-immunoreactive cells in the hippocampal complex were pyramidal-like and bitufted neurons, which were mainly found in the stratum oriens and stratum pyramidale of the hippocampus, and in the stratum moleculare and hilus of the fascia dentata. Heavily stained cells were found in the deep part of the stratum granulare. Intense calbindin immunoreactivity occurred mainly in the granule cell and molecular layers of the dentate gyrus and in the mossy fibre layer. The most outstanding feature in the hippocampal complex of the hedgehog was the extension of calbindin immunoreactivity to CA1 field of the hippocampus, suggesting, in agreement with other reports, that mossy fibres can establish synaptic contacts throughout the pyramidal cell layer.

Tobacco, physical exercise and lipid profile. A group of 572 young cadets from the General Military Academy in Zaragoza (AGEMZA) with a mean age of 19.9 years was studied in two different situations: on admission to the AGEMZA, when physical activity was very intensive (A) and after 8 months, by which time they had all received identical diets and physical activity was considerably reduced (B). On both occasions they were asked about their smoking habits and their personal and family histories. Their height and weight were recorded and a sample of venous blood was taken to determine the lipid, biochemical and haematological profiles. We found that more smokers had a family history of sudden death or acute myocardial infarction than the non-smokers. The smokers also showed a lower HDL cholesterol level (54.3 +/- 9.8 mg.dl-1 +/- SD) than the non-smokers (59.4 +/- 10.9) (P less than 0.0001) and a higher level of triglycerides (75.4 +/- 24.7 mg.dl-1) than the non-smokers (65.4 +/- 21.1 mg.dl-1). The smokers had a higher white cell count (8194 +/- 1981 vs 7332 +/- 1672 cells. 10mm-3) (P less than 0.001), a higher haemoglobin value (14.9 +/- 0.9 vs 14.6 +/- 0.9 g.dl-1) (P less than 0.004) and a higher haematocrit value (44.2 +/- 2.3 vs 43.6 +/- 2.7%) (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

High-performance liquid chromatographic separation of the enantiomers of hydroxychloroquine and its major metabolites in biological fluids using an alpha 1-acid glycoprotein stationary phase. An enantioselective two-stage off-line assay has been developed for the analysis of hydroxychloroquine and its three major metabolites in biological fluids. The first non-stereoselective stage of the assay (PRP-1 column) separates and quantitates parent drug and metabolites. Fractions containing hydroxychloroquine and each of the metabolites are collected manually, evaporated, reconstituted in mobile phase and re-injected onto an alpha 1-acid glycoprotein column to separate and determine proportions of individual enantiomers. Preliminary results from patients samples indicate that the disposition of hydroxychloroquine and its major metabolites is enantioselective. p6

The nicotinic receptor genes. The causative factor(s) of Alzheimer's disease (AD) are presently unknown. However, it has been shown that the number as well as the fraction of high- to low-affinity nicotine binding sites is altered in patients suffering from this disease. This finding, along with the identification of seven genes which code for nicotinic receptors expressed in the mammalian brain, has led to the idea that one nicotinic receptor subtype may be specifically altered in AD. The present article reviews how, through a molecular genetic approach, a family of genes coding for nicotinic acetylcholine receptor subtypes was uncovered. Also discussed is the use of in situ hybridization to determine the distribution of expression of the mRNA encoding for each receptor subtype and the patch clamp technique to characterize their biophysical properties. Determination of the promoters of these genes, as well as the properties of the expressed receptor subtypes, may make it possible to design new specific nicotinic receptor subtype drugs that will treat not only the symptoms of AD but the progression of the disease process as well.

A comparison of static and dynamic characteristics between rectus eye muscle and linear muscle model predictions. The characteristics of a muscle model are analyzed using rectus eye muscle parameter values and compared to rectus eye muscle data. The muscle is modeled as a viscoelastic parallel combination connected to a parallel combination of active state tension generator, viscosity element, and length tension elastic element. Each of the elements is linear and their existence is supported with physiological evidence. The static and dynamic properties of the muscle model are compared to rectus eye muscle data. The length-tension characteristics of the model are in good agreement with the data within the operating region of the muscle. With the muscle model incorporated into a lever system to match the isotonic experiment paradigm, simulation results for this linear system yield a nonlinear force-velocity curve. Moreover, the family of force-velocity curves generated with different stimulus rates reported in the literature match the predictions of the model without parametric changes. The results of this paper are important in studies involving the oculomotor plant and oculomotor neural networks. Additionally, these results may be applicable to other muscles.

Prevalence and characteristics of anti-single-stranded DNA antibodies in localized scleroderma. Comparison with systemic lupus erythematosus. Prevalence, levels, and immunoglobulin classes of anti-single-stranded DNA antibodies were determined by an enzyme-linked immunosorbent assay in 52 patients with localized scleroderma (33 with morphea, four with generalized morphea, and 15 with linear scleroderma), in 60 healthy controls, and, for comparison, in 31 patients with systemic lupus erythematosus. Localized scleroderma revealed a significant prevalence of anti-single-stranded DNA antibodies, mainly characterized by high levels and IgM and IgA isotypes. Comparison of antibody characteristics in different clinical forms of localized scleroderma showed some significant differences (levels and immunoglobulin isotypes). Comparison with systemic lupus erythematosus showed that frequency, high levels, and IgG isotype of anti-single-stranded DNA antibodies significantly prevailed in systemic lupus erythematosus, while the IgM isotype significantly prevailed in localized scleroderma. However, generalized morphea and linear scleroderma did not significantly differ from systemic lupus erythematosus as regards antibody frequency and prevalence of high antibody levels.

Distribution of Goodpasture antigens within various human basement membranes. Collagenase-digested basement-membrane preparations from human kidney glomeruli, kidney tubules, lung, choroid plexus, aorta, intestine, and placenta were analysed according to their reactivity to anti-glomerular basement membrane (anti-GBM) antibody-positive Goodpasture sera. Sodium dodecylsulphate polyacryl gel electrophoresis (SDS-PAGE), and immunoblotting were performed after antigen enrichment by passage of the collagenase digests through an anion-exchange column. Reactivity of anti-GBM antibodies with one to three monomers (24, 26 and 28 kD) and two dimers (44 and 50 kD) were demonstrated in basement membrane preparations of kidney glomeruli, kidney tubules, lung, placenta, and aorta. In basement membranes of choroid plexus reactivity with only the 28 kD monomer and the 50 kD dimer were identified. In intestinal basement membrane, reactivity was restricted to the 50 kD dimer. Analysis of the amounts of Goodpasture antigen by inhibition ELISA demonstrated that the highest concentration were in glomerular basement membrane, while the lowest were found in aortic basement membrane. The results indicate that Goodpasture antigens are common to all the basement membranes investigated. The differences in antigen concentration and in reactivity on immunoblotting may indicate different antigen amounts, a heterogeneity of collagen IV within the various basement membranes, or differences in antigen accessibility within the membranes. We conclude that the primary clinical restriction of the anti-GBM disease to lungs and kidneys is not explained by a preservation of the antigen to this basement membrane. Rather, the clinical pattern may be influenced by differences in the molecular composition of the basement membranes as well as by non-immunological mechanisms.

Phenomenological characterization of eardrum transduction. A phenomenological description of the transduction effected by the eardrum is presented. That description is provided by a transfer matrix, whose elements define those measurements sufficient to characterize eardrum transduction. Causality provides constraints on the matrix elements. In addition, measurements of the matrix elements can determine whether they satisfy constraints imposed by minimum-phase behavior and the principle of reciprocity. Those constraints may be used either to reduce the number of measurements necessary to characterize the eardrum or to check the consistency of measurements that overdetermine the system. Within its region of validity, the transfer matrix of the eardrum provides a common ground for the comparison between theory and experiment. As an example, a simple model for the transduction characteristics of the eardrum, defined completely in terms of measurable quantities, is presented.

Three-dimensional intravascular ultrasound imaging of normal and diseased canine and human arteries. This study reports three-dimensional reconstruction of two-dimensional intravascular ultrasound images obtained along 5 cm vessel segments. Each three-dimensional image was produced by computerized "stacking" of a set of consecutive two-dimensional images (mode 90 images per set; range 32 to 256). Three-dimensional images (n = 26) were obtained from 11 human normal and atherosclerotic arteries (three in vitro and eight in vivo) and five in vivo canine studies. In vivo human examinations included three iliac, one deep, and three superficial femoral arteries and one aortic dissection. Five in vivo canine vessels (three iliac stenoses and two aortic dissections) were imaged before and after intraluminal stent deployment. Images were displayed on a gray-scale monitor, allowing examination of vessel images as complete cylinders or longitudinal hemisections in any user-defined plane. This enabled global examination of vascular segments and identified luminal shape, wall thickness, and distribution and morphology of plaques. Reconstructions of aortic dissections illustrated the extent of the dissection and produced an anatomic picture of the false lumen. Three-dimensional imaging enhanced stent deployment by identifying the site for deployment, dimensions of the vessel lumen, and changes in morphology after stent insertion. There was good correlation in vessel dimensions measured by angiography, two-dimensional intravascular ultrasonography and longitudinal gray-scale reconstructions (r = 0.74 to 0.95; p = 0.34 to 0.001) but poor correlation with measurements from three-dimensional surface-rendered images (r = 0.13 to 0.48; p = 0.42 to 0.87). We conclude that three-dimensional intravascular ultrasound imaging is an innovative new method for identifying the type, extent, and spatial configuration of arterial disease, with promising diagnostic and therapeutic applications.

Depressed delayed cutaneous hypersensitivity in alcoholic hepatitis. Delayed cutaneous hypersensitivity was studied in 10 patients with severe alcoholic hepatitis, 9 patients with either inactive alcoholic cirrhosis or alcoholic fatty liver, and 10 agematched controls. The mean response of the alcoholic hepatitis group was significantly less compared to controls for SK-SD (P less than 0.001), mumps (P less than 0.001), trichophyton (P less than 0.025), and Candida albicans (P less than 0.025). Upon clinical recovery, the response of the 6 surviving patients with alcoholic hepatitis was similar to controls for 4 of the 5 antigens tested, and the improvements in response to SK-SD and Candida albicans were significant (P less than 0.02 and P less than 0.05). The mean percentage and absolute numbers of thymus-derived lymphocytes were significantly less in the alcoholic hepatitis group compared with controls. Both the alcoholic hepatitis patients and patients with less advanced alcoholic liver disease had a diminished response to concanavalin A and phytohemagglutinin. This study demonstrates a reversible depression of delayed cutaneous hypersensitivity in alcoholic hepatitis. Several mechanisms may help account for this finding. We recommend that skin tests in patients with alcoholic hepatitis be interpreted with this phenomenon in mind.

Incidence and prediction of filled teeth from 12 to 18 years of age in a district in Norway. The present study investigated whether the incidence or prevalence of filled teeth/approximal surfaces at one age could be predictive for the incidence in another period or for the prevalence at the age of 18. The study was conducted in 12-18-yr-olds in Norway. Regression analysis showed that the best prognosis for subsequent incidence of filled teeth/approximal surfaces could be made at the age of 15. By using regression analysis or discriminant analysis it was possible at the age of 15 to predict with high accuracy those who would acquire more fillings than the median at the age of 18. Discriminant analysis with one predictor variable is suggested for clinical use. The variable that discriminated best between above and below median number of new fillings in the period 15-18 yr was untreated lesions in the inner half of the enamel in the approximal surfaces of premolars and molars at the age of 15. From the use of simple prediction tools, it was concluded that individuals at the age of 15 with a low prevalence of filled teeth/filled approximal surfaces and without untreated approximal lesions would be subjected to a low incidence of new fillings until the age of 18.

The continuous inhalation of oxygen-15 for assessing regional oxygen extraction in the brain of man. A non-invasive steady-state method for studying the regional accumulation of oxygen in the brain by continuously inhaling Oxygen-15 has been investigated. Oxygen respiration by tissue results in the formation of water of metabolism which may be considered as the "exhaust product" of respiration. In turn the steady-state distribution of this product may be related to that of oxygen utilization. It has been found in monkeys that an appreciable component of the signal, recorded over the head during the inhalation of 15O2, is attributable to the local production of 15O-labelled water of metabolism. In man the distribution of radioactivity recorded over the head during 15O2 inhalation clearly relates to active cerebral tissue. Theoretically the respiration product is linearly dependent on the oxygen extraction ratio of the tissue, and at normal cerebral perfusion it is less sensitive to changes in blood flow. At low rates of perfusion a more linear dependence on flow is shown. The dual dependence on blood flow and oxygen extraction limits the interpretation of the cerebral distribution obtained with this technique. Means for obtaining more definitive measurements with this approach are discussed.

Collaborative study of a gas-liquid chromatographic method for the analysis of chlorobenzilate and chloropropylate. A gas-liquid chromatographic method for the determination of chlorobenzilate and chloropropylate in liquid formulations containing about 46 and 26% active ingredient, respectively, was collaboratively studied, using a matched pair scheme. The samples were dissolved in acetone containing debenzyl succinate as an internal standard and chromatographed on Carbowax 20M, using a flame ionization detector. Analyses of 4 samples by 13 collaborators using peak height measurements showed the following results: chlorobenzilate-2.5% overall coefficient of variation, 1.0% coefficient of variation for the random error, and 0.7% systematic error; chloropropylate-2.0, 1.4, and 0.4%, respectively. The method has been adopted as official first action.

Diagnosis of cerebral amyloid angiopathy by enzyme-linked immunosorbent assay of cystatin C in cerebrospinal fluid. An abnormally low level of cystatin C in the cerebrospinal fluid is a diagnostic marker for the hereditary form of brain hemorrhage associated with amyloidosis that was first identified in Iceland. We developed an assay for cystatin C to use in the diagnosis of patients with cerebral amyloid angiopathy and brain hemorrhage. This test consists of a sandwich enzyme-linked immunosorbent assay using monoclonal mouse anticystatin C and polyclonal rabbit anticystatin C antibodies. The cystatin C level was assayed in cerebrospinal fluid samples from 29 patients with brain hemorrhage and 45 control patients with other neurological diseases. Fifteen patients with brain hemorrhage showed low cystatin C levels (less than or equal to 70 ng/ml) in a clinical setting in which the positive and negative findings were compatible with a diagnosis of cerebral amyloid angiopathy. Immunohistological examination of brain tissue obtained by biopsy from two of the 15 patients confirmed the diagnosis of cerebral amyloid angiopathy and identified the deposition of cystatin C and beta-protein. This enzyme-linked immunosorbent assay is simple to perform and may be useful for investigating patients suspected of having cerebral amyloid angiopathy with brain hemorrhage and the deposition of cystatin C.

The effect of bicarbonate and distilled water on sickle cell trait hematuria and in vitro studies on the interaction of osmolality and pH on erythrocyte sickling in sickle cell trait. The effect of intravenously administered distilled water was examined alone and during alkalization in a patient with gross hematuria associated with the sickle cell trait. On each of 4 occasions hematuria ceased promptly after the infusion of distilled water. Bicarbonate therapy also consistently decreased hematuria. In vitro studies on erythrocytes from another patient with sickle cell trait and hematuria demonstrated that slight increases in urinary pH similar to those that occur in the urine during alkalization can reverse or prevent erythrocyte sickling in the sicle cell trait. If patients with the sickle cell trait are hydrated adequately and have a good rate of urine flow distilled water can be given intravenously with virtually no danger of acute tubular necrosis secondary to erythrocyte hemolysis.

Pulpal vascular changes in inflammation. Changes in pulpal vessels in experimentally induced acute and chronic pulpitis in dog tooth were investigated using corrosive resin casts and scanning electron microscopic examination. Following a cavity preparation without water spray, increased permeability of blood vessels occurred in the primary stage of acute pulpitis. This was evidenced by the extravasation of resin from the vessel. This phenomenon was found initially in the venular network as well as in the capillary network located under the dentin. The morphological change was minimal in the vascular network underneath the cavity. This is in contrast to an expanded and tortuous vascular network representing an ulceration which was found around an abscess in chronic pulpitis. Furthermore, formation of vascular loops and AVAlc close to the inflamed region may represent a protective change in the pulp against inflammation.

Management of early inflammatory arthritis. Intervention with immunomodulatory agents: T cell vaccination. Current theories of the aetiology of RA point to a central role for the trimolecular complex comprising the MHC class II molecule on the surface of the APC, the antigenic peptide and the TCR on the disease-inducing T cell. Thus the arthritogenic T cell is an important target for new therapy. However, it cannot be directly identified because the causative antigen is unknown, so indirect techniques such as TCV and TCR peptide vaccination are required. In TCV, T cells thought to mediate the disease, in an activated and attenuated form, are injected into the patient, who then develops a specific immune response against these pathogenic T cells. TCV has been shown to be effective in protecting against and treating a variety of animal models of autoimmune disease, including AA, EAE and IDDM in NOD mice. The vaccines initially comprised clones and lines of T cells shown to be capable of transferring the disease, but later unseparated LN cells were also shown to be effective, paralleling more closely the human situation. Interestingly, it has become clear that TCV does not create its own regulatory network but amplifies a natural immunoregulatory network which forms as the disease develops. The major stimulating moiety on the vaccinating T cell is its receptor (anti-idiotypic response), although there is also an anti-ergotypic (anti-activated T cell) response. For this reason the technique of TCR peptide vaccination was developed, which utilizes only a short peptide from the TCR of the disease-causing cells to stimulate an immune response against them. This is effective in the prevention and treatment of EAE, where there is a preferential usage of TCR-V beta 8 by encephalitogenic T cells. The application of both these techniques to human autoimmune disease is in its infancy. Studies of TCV in MS and RA have not shown clear-cut clinical benefit, although immunological changes have been observed; comparison of methodology with the animal work and assessment of results are complex and further studies are in progress. Studies of TCR peptide vaccination in MS and RA are handicapped by the lack of a consensus on TCR usage in these conditions, but a limited study is underway in MS.

The actions of parathyroid hormone on bone: relation to bone remodeling and turnover, calcium homeostasis, and metabolic bone diseases. II. PTH and bone cells: bone turnover and plasma calcium regulation. Kinetic and morphologic studies in patients with parathyroid disease, and a wide variety of studies in experimental animals indicate that one major effect of PTH is to increase the proliferation of osteoprogenitor cells into osteoclasts and so to increase bone turnover. PTH stimulates bone cells by increasing cell membrane permeability to calcium and consequently increasing calcium influx and by activating membrane-bound adenyl-cyclase. It is likely that the former event precedes the latter and that calcium is the second messenger and cyclic AMP the third messenger. PTH increases the production by bone cells of lactate, citric and carbonic acids, lysosomal enzymes, collagenase, and hyaluronic acid, some or all of which are concerned in the mechanism of bone resorption. With the exception of lactate which probably comes mainly from osteocytes, the increase in metabolic activity is largely due to the increase in the number of osteoclasts. There is also ultrastructural, biochemical, and biophysical evidence that PTH stimulates existing osteoclasts, but this most likely represents the transformation of inactive cells into an active state, and is a transient and nonsustainable effect. As yet, there is no evidence that either increased osteoprogenitor cell proliferation or increased osteoclast activity is mediated by adenyl-cyclase activation. PTH also acts on the deep osteocyte to cause rapid mobilization of calcium from the zone of hypomineralized metabolically active perilacunar bone. This effect is mediated by adenyl-cyclase activation and is preceded by a slight fall in plasma calcium probably due to the movement of calcium into bone cells. The function of this rapid hypercalcemic response to PTH is correct errors in the prevailing steady-state level of plasma calcium...

A survey of the natural occurrence of Fusarium mycotoxins, deoxynivalenol, nivalenol and zearalenone, in cereals harvested in the Netherlands. A survey for the natural occurrence of Fusarium mycotoxins, deoxynivalenol (DON), nivalenol (NIV) and zearalenone (ZEN), in Dutch cereals (totaling 29 samples) harvested in 1984/1985, showed that 90%, 79% and 62% of samples were contaminated with DON, NIV and ZEN, respectively. Average contents (ng/g) in the total of positive samples were 221 (DON), 123 (NIV) and 61 (ZEN). Among the cereals examined, the highest concentrations (ng/g) was 3198 (DON), 1875 (NIV) and 677 (ZEN) in a yellow corn sample for animal feed. The results of this survey show that Dutch cereals were relatively significantly contaminated with Fusarium mycotoxins.

Histochemical demonstration of lysosomal hydrolase activity in endometrial mononuclear cells. II. Abnormal endometrium. The mononuclear cells in the endometrial stoma change in reactivity for lysosomal hydrolases during the menstrual cycle. Lymphoid follicles may occur in the stroma in any phase of the cycle and have been found in gestational endometrium. However, these cells have no significant lysosomal activity. Alterations in the endometrium are reflected in modified patterns of activity. Endometritis, association with an intrauterine contraceptive device, pregnancy, and adenocarcinoma result in increased numbers and staining intensity of mononuclear cells. In contrast, no consistent changes were apparent in foci of glandular hyperplasia, and decreased staining was seen in atrophic areas of endometrium. These data suggest that interstitial mononuclear cells are a sensitive monitor of morphologic changes in the endometrium.

Excretory-secretory products of Echinostoma paraensei sporocysts mediate interference with Biomphalaria glabrata hemocyte functions. Miracidia of Echinostoma paraensei were cultured in medium containing 14C-labeled amino acids, allowed to transform into sporocysts, and their excretory/secretory products (E-S) were collected and characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis and autoradiography. Effects of E-S on hemocytes of Biomphalaria glabrata were also assessed. E-S collected during day 1 of culture (E-S1) contained several polypeptides, none of which were labeled, suggesting that E-S1 are largely preformed. E-S1 significantly depressed the ability of hemocytes to phagocytose sheep red blood cells (SRBC), but otherwise had little effect on hemocyte structure or behavior. E-S released by sporocysts in day-2 cultures (E-S2) and in older cultures generally were similar and also contained several polypeptides, many of which were labeled, indicating active synthesis of E-S in vitro. E-S2 strongly inhibited hemocyte uptake of SRBC. Also, hemocytes pretreated with E-S2 assumed a spherical shape and failed to spread normally. E-S obtained through 10 days of culture mediated this effect. Active components of E-S2 were greater than 100 kDa in their native configuration, were heat- and trypsin-labile, and were bound by anti-E-S antibodies. Both greater than 200- and 80-kDa bands were prominent in anti-E-S immunoprecipitates. Hemocytes derived from snails of the 13-16-R1 strain of B. glabrata (a strain resistant to infection with Schistosoma mansoni), when pretreated with E-S2, bound to sporocysts of S. mansoni but lost their ability to damage such sporocysts. E-S2 interfered with hemocyte functions in ways inferred from earlier classic in vivo studies of trematode-snail interactions.

Initial and steady state pharmacokinetics of cilazapril in congestive cardiac failure. Twenty one patients with NYHA class II-III congestive heart failure received single ascending doses of 0.5, 1.25 and 2.5 mg cilazapril daily followed by the minimum effective dose for six weeks. Fifteen patients completed the study, but the data from only 11 were sufficiently complete for kinetic evaluation. The pharmacokinetics of the metabolite, cilazaprilat, after a single dose of 0.5 mg cilazapril were similar to previous observations in healthy volunteers at identical dosage. Repeat administration, however, led to greater accumulation than previously observed in volunteers at the higher dosages of 1.25 or 5 mg given for 8 days. Seven patients experienced adverse events. Four were severe, leading to withdrawal of the patients from the study, but only one event was related to cilazapril. Of the other three, one suffered a myocardial infarction and subsequently died due to worsening congestive heart failure. One other patient was withdrawn with two adverse events probably related to cilazapril. No other deaths occurred amongst the study population, and there were no significant abnormalities in haematology or blood chemistry.

The synthesis of fetal hemoglobin types in red blood cells and in BFU-E derived colonies from peripheral blood of patients with sickle cell anemia, beta+ - and delta beta-thalassemia, various forms of hereditary persistence of fetal hemoglobin, normal adults and newborn. The biosynthesis of two types of human fetal hemoglobin (Hb F), namely Hb F with G gamma chains having glycine in position 136 and Hb F with A gamma chains having alanine in position 136, was studied in blood samples and in cultures of erythroid precursors from blood of patients with different hemoglobinopathies. High pressure liquid chromatography (HPLC) was adapted to allow the separation of the methionyl-containing tryptic peptides G gamma T-15 and A gamma T-15 (which include the Gly leads to Ala polymorphism at position 136) from a digest of microquantitites of 35S-methionyl labelled Hb F. This method was sensitive enough to quantitate the relative production of the G ygamma and A gamma chains by erythroid colonies derived from cloned Burst Forming Units (bfu-e) which were cultured for 16 days on methylcellulose. The production of Hb F in these colonies was generally higher than the level of Hb F in blood except for subjects with the G gamma A gamma-HPFH heterozygosity. The G gamma to A gamma ratio in the Nb F produced in cultures of cells from G gamma delta beta-thalassemia or G gamma-HPFH heterozygotes was lower and that from A gamma-HPFH heterosygotes was higher than the ratios in the Hb F of the corresponding peripheral blood cells. Mixtures of G gamma and A gamma chains were present in cell cultures of SS patients, beta+-thalassemia homozygotes and G gamma A gamma-HPFH heterozygotes in a ratio similar to that in the Hb F of mature red cells. These data suggest that erythroblasts in BFU-E derived colonies reactivate all available gamma chain structural genes, both in cis and in trans to the abnormal determinant. Hb F biosynthesis by adult blood samples concerns primarily the G gamma chains. This was particularly striking for blood samples in which erythroblasts were absent and the biosynthesis took place in fetal reticulocytes. Thus, the F-retuculocytes in blood of A gamma-HPFH heterozygotes with about 5% Hb F of the A gamma type produced primarily Hb F with G gamma chains. Similar differences were observed for G gamma A gamma-HPFH heterozygotes and, less strinkingly, for SS patients. A satisfactory explanation for this observation has not yet been obtained.

The structure of anaerobic bacterial communities in the hypolimnia of several Michigan lakes. The structure of bacterial communities, the distribution of sulfide and oxygen, bacteriochlorophyll concentrations, and the temperature profile were determined for the anaerobic hypolimnia of two lakes in southern Michigan. Information from these studies, plus qualitative observations of two other lakes and two ponds over a 4-year period were used to correlate the spatial distribution of the populations, cell size, arrangement of photosynthetic vesicles or lamellae, presence of gas vacuoles or flagella, sulfur deposition, and environmental factors. On the basis of these results, three communities designated as A, B, and C were defined. The upper (A) community consisted of sequentially layered purple sulfur bacteria including two or more of the following genera: Thiopedia, Thiospirillum, Thiocystis, or Chromatium. The middle (B) community consisted of sequential layers of green bacteria from one or more of the following genera: Pelodictyon, Clathrochloris, Chlorochromatium, or Prosthecochloris. The lowest (C)community contained previously unreported gas-vacuolate colorless bacteria 0 to 0.7 m above the sediment. Microstratification (0.1- to 0.2-m layers) of populations was observed within the A and B communities.

Bafilomycin A1 inhibits the targeting of lysosomal acid hydrolases in cultured hepatocytes. Effects of bafilomycin A1, an inhibitor of vacuolar H(+)-ATPase, on the synthesis and processing of cathepsin D and cathepsin H were investigated in primary cultured rat hepatocytes. Pulse-chase experiments showed that after being synthesized as procathepsin D and procathepsin H the precursors were converted into mature forms in the control cells as the chase time elapsed. However, in the presence of 5 x 10(-7) M of bafilomycin A1, both precursors were largely secreted into the medium and no mature forms were found within the cells. Thus bafilomycin A1 mimics lysosomotropic amines with regard to perturbation of the targeting of lysosomal acid hydrolases. In contrast, bafilomycin A1 was found not to inhibit processings of proalbumin and procomplement component 3, which are thought to occur at the acidic trans-Golgi, implying that the proteolytic event of the proproteins is not sensitive to an increase of intra-Golgi pH. The results suggest that bafilomycin A1 is useful as a pH-perturbant to study the role of acidity in living cells.

Induction of rat liver alkaline phosphatase by bile duct ligation. Bile duct ligation causes a five- to sevenfold increase in the activity of rat liver alkaline phosphatase within 12 hours after ligation and a similar rise in the activity of alkaline phosphatase in serum. The increased serum activity is due entirely to the appearance of a new isoenzyme that has the properties of rat liver alkaline phosphatase. The increase in both serum and liver alkaline phosphatase is prevented by the prior administration of cycloheximide in a dose that inhibits protein synthesis by 70%. Rat liver alkaline phosphatase was then purified to homogeneity. Antibody was raised to purified rat liver alkaline phosphatase in rabbits. The antibody was coupled to sepharose 4B and affinity columns made. (3)-H-leucine was then injected into the portal veins of sham operated rats and rats with bile duct ligation four hours after ligation. One hour after injection and five hours after ligation, animals were sacrificed. Liver alkaline phosphatase was purified by means of affinity chromatography and double immunoprecipitation with rabbit antibody to rat liver alkaline phosphatase and goat anti-rabbit gamma globulin. Bile duct ligation increased the incorporation of (3)-H-leucine into liver alkaline phosphatase more than threefold compared with sham operated rats, 164 CPM/mg protein vs. 49 CPM/mg protein (p < .001). The data indicate that the increased activity of rat liver alkaline phosphatase after bile duct ligation is due to enzyme induction rather than to activation of a pre-existing, relatively inactive enzyme.

Purification and biochemical properties of complex flagella isolated from Rhizobium lupini H13-3. 1. The complex flagella of Rhizobium lupini H13-3 differ from plain bacterial flagella in the fine structure of their filaments dominated by conspicuous helical bands, in their fragility and their resistance against heat decomposition. To elucidate the basis of these differences, the composition of complex filaments and their subunits was analysed. 2. Isolated complex flagella containing the filament and hook protions were purified by differential centrifugation. Hooks were separated by ultracentrifugation after acid degradation of filaments at pH 2. The complex filaments consist of 43 000 dalton monomers (cx-flagellin), the hooks are composed of 41 000 dalton subunits. 3. Amino acid analysis of cx-flagellin indicated the presence of approx. 417 amino acid residues. These comprise 47% hydrophobic residues and 21% Asp and Glu (or amides), but no Cys, His, Pro and Trp. No carbohydrate, phosphate or lipid moieties have been detected. Fingerprint analysis after tryptic digestion yields approx. 36 peptides, about half of them clustered in the neutral region. A comparison with the composition of varous known flagellins from plain flagella indicates a 7% higher content of hydrophobic amino acid residues in complex filaments; this is largely compensated for by the higher content of Glu and Asp (presumably as Gln and Asn) in plain filaments. 4. Immunodiffusion and immunoelectrophoresis of cx-flagellin yield single precipitin bands indicating homogeneity. In contrast, isoelectric focusing lead to three close-running bands around pH4.7. When isolated, the two major bands again produced an "isoelectric spectrum" suggesting that it reflects an allomorphism of cx-flagellin. 5. Self-assembly experiments with cx-flagellin lead to coiled fibres including helical regions, but not to intact filaments. The products resemble heat-denatured complex filaments and may represent intermediates between monomers and complete polymers.

A transformation-competent recombinant between v-src and Rous-associated virus RAV-1. The LTR, v-src, LTR provirus, which arose by the reverse transcription and integration of src mRNA in the H-19 hamster tumor, has been successfully rescued by fusion with chicken fibroblasts infected with Rous-associated virus RAV-1. One rescued virus, E6, acquired 1 kilobase of the 5' end of the gag gene structure. Recombination took place in the region of 15-nucleotide homology exactly between v-src exon (position 7054) and gag (position 1417). This recombination resulted in the alteration of src splice acceptor site sequences, but this site is maintained as a functional splice acceptor site. The nucleotide structure of the long terminal repeat of recombinant E6 virus suggests that it arose by the intermolecular jump of reverse transcription from RAV-1 to src mRNA and then the switch of templates between already depicted regions of homology. The second jump of reverse transcription was apparently an intramolecular event. The acquisition of 1 kilobase of the 5' gag by E6 resulted in maintaining the balance of unspliced and spliced E6 RNAs and assured the replication advantage of rescued E6 virus over rescued F6 virus, the genome of which corresponds to that present in ancestral H-19 cells.

Plasma lipoprotein changes during oral contraception. Changes in plasma concentration of high-density lipoprotein (HDL) cholesterol concentration were measured in healthy young women who received 21-days' oral treatment with either norethisterone acetate (1, 2, or 5 mg daily) or ethinyloestradiol (20 or 50 microgram daily). Similar measurements were also made in groups of women receiving progestogens or oestrogens for gynaecological indications, and in women taking oral contraceptives. Oestrogens alone stimulate increases in HDL-cholesterol, while progestogens alone suppress the concentration. Combinations of oestrogens and progestogens have variable effects depending on the relative doses and chemical compositions of the two hormones. Because HDL-cholesterol concentration is thought to be negatively correlated to cardiovascular disease risks, products which induce a large decrease are to be avoided, though other risk factors must be taken into account in the selection of oral contraceptives.

A quantitative method for the detection of sulfonamide residues in meat and milk samples with a high-performance thin-layer chromatographic method. Sulfonamides are widely used in veterinary medicine for prophylactic purposes and for the treatment of various infections of food-producing animals. This means that residues of these drugs and their possible metabolites may occur in food of animal origin. In Belgium, a zero tolerance level for sulfonamides in edible animal tissues has been set. In order to check this zero level on a routine basis, a rapid and sensitive method has to be available. For this purpose, a quantitative high-performance thin-layer chromatographic (HPTLC) method for the detection of sulfonamide residues in animal tissue and milk samples has been developed. The sample preparation consists of a liquid extraction followed by a solid phase extraction (SPE) on disposable columns for the meat samples and a matrix solid phase dispersion (MSPD) for the milk samples. A three-multiple development chromatographic system is used for the separation and a derivatization with fluorescamine decreases the minimal detectable quantity per spot from 1.42 to 0.32 ng. The limit of quantification is 4 micrograms/kg for milk and meat samples.

[Clinical evaluation of recombinant human G-CSF in children with cancer]. Recombinant human granulocyte colony-stimulating factor (rG-CSF), produced by Chinese hamster ovary cells, was administered in 69 chemotherapy-induced neutropenic pediatric patients (pts) with malignant tumors. Each pt received two cycles of the same chemotherapy and had neutropenia with absolute neutrophil counts (ANC) less than 500/microliter in the first cycle. Initiating 72 hours after termination of chemotherapy in the second cycle, rG-CSF (2 micrograms/kg/day) was given subcutaneously or intravenously to each pt for 10 days. rG-CSF significantly increased ANC at nadir; 72 +/- 14 vs. 206 +/- 40/microliter (data in the first cycle vs. data in the second cycle, respectively), and reduced the period of neutropenia with ANC less than 500/microliter; 9.7 +/- 0.6 vs. 5.1 +/- 0.6 days, and the period for restoration to ANC greater than or equal to 1,000/microliter after initiation of chemotherapy; 25.5 +/- 0.6 vs 17.5 +/- 0.9 days. rG-CSF did not affect other components of peripheral blood. The number of days with fever greater than or equal to 38 degrees C was significantly reduced by rG-CSF treatment. Neck pain and lumbago were observed in one pt, pollakisuria in one pt, and elevation of the serum levels of LDH and uric acid in one pt, however these were mild to moderate, transient, and resolved without any specific treatment. We concluded that rG-CSF was effective in neutropenia induced by intensive chemotherapy for malignant tumors without any serious side effects.

Survival characteristics of the epigastric free flap in DA-rats. Epigastic flaps measuring approximately 6 x 4 cm with borders related to well-defined anatomical structures were isografted (Dark Agouty to Dark Agouty inbred rats) with or without anastomosing their epigastric pedicle, after various periods of ischaemia, ranging from 0 to 120 h. During the ischaemic insult the flaps were stored at 0 degrees C in a hypertonic citrate solution. The non-revascularized flaps exhibited survival percentages varying from 2 to 34% (mean, 16%) of the original flap,. independent of the storage interval. The flaps that were revascularized after ischaemia had a 100% survival when transplanted immediately after isolation and following 48 h of cold storage. Mean survival percentages of 78% after 72 h of ischaemia, 32% after 96 h, and 4% after 120 h of ischaemia were found. It is concluded that the model described in this study is suitable for free flap research, because of its delineated borders. However, when the area of flap survival is lower than 30% in revascularized flaps there is a distinct likelihood that the flaps have survived regardless of the pedicle as simple Wolfe or composite grafts. Results must therefore be interpreted with great care.

Inhibition of tumour development in the partially resected, proliferating rat urinary bladder. Autoradiographic studies have shown that the urothelium of the rat urinary bladder is capable to considerably proliferate in response to a partial cystectomy (one-third resection of the bladder) as is indicated by a 190-fold increase of the 3H-thymidine labelling index above normal levels 45 h postoperatively and an enormous increase of the compartment of proliferating cells (so-called growth fraction). The stimulated urothelial proliferation can be synchronized by multiple, fractionated doses of hydroxyurea (HU), resulting in a high degree of synchrony. Based on these findings, the partial cystectomy model seemed to be a useful tool to examine whether stimulated proliferation exerts a modifying effect on initiation of urothelial carcinogenesis. Following feeding N-butyl-N-(4-hydroxybutyl)-nitrosamine by gavage in 3 fractionated doses during most pronounced proliferation 30, 45 and 70 h postoperatively, the development of bladder tumors proved to be significantly dose- and time-related inhibited. Accordingly, N-methyl-N-nitrosourea (MNU)-induced tumour formation was considerably reduced following intravesicular instillation of the carcinogen at a single dose 45 h postoperatively, when stimulated DNA synthesis reached its peak. Experiments testing a possible cell cycle specific dependence of MNU-initiated tumor development in the partially resected bladder after synchronization of the stimulated proliferation by HU revealed an inhibition of urothelial carcinogenesis in particular, when the carcinogen was administered during the early DNA synthesis phase. The mechanisms underlying the observed inhibition of tumor development in the regeneration urinary bladder are unknown. It is assumed that an increased capacity of the proliferating urothelial cells to repair carcinogen-induced DNA-damage may play an important role.

Structural aspects of gas exchange. The lung is composed of several million small air spaces, lined by a delicate tissue membrane separating air from capillary blood. The design features of the gas exchange region in the lung are optimal for gaseous diffusion, by having a very extensive contact surface but with a minimal tissue barrier composed of an epithelial and endothelial layer separating an interstitial layer. The extent of the gas exchange surface in adult lungs is determined by general maturation which in turn is influenced by metabolic requirements of the organism. Environmental factors can modulate the pattern of ultimate lung development. Lung inflation causes air spaces to expand mainly by a process of tissue unfolding beneath an extremely thin layer of alveolar surfactant. This ensures cellular integrity during extreme deformations while at the same time providing a reserve of gas exchange surface so that functional diffusion capacity at all lung volumes is less than the structural maximum.

Evaluation of a screening test for detecting urinary tract infection in newborns and infants. The results of a study of a screening test for urinary tract infection (UTI) in infants under 18 months is reported. Two hundred and forty three urine specimens were tested in the laboratory using AMES Multistix 8SG reagent strips read by photometer. The strips included three potential markers for urinary tract infection: leucocyte esterase, nitrite, and protein. The predictive value of a positive result (PPV) was low. The predictive value of negative test (NPV) when combining the screen of leucocyte esterase, nitrite, and protein was 99.4% with no difference between boys and girls. The test for leucocyte esterase had a 97.6% negative predictive value. An examination of the results by age confirms the good NPV in all age groups. Paediatricians should find Multistix 8SG strips a useful aid in the diagnosis of urinary tract infection in infants, and that costly culture of samples with negative strip tests can be avoided.

Glucagon: prehospital therapy for hypoglycemia. This study evaluated the efficacy of glucagon for prehospital therapy of hypoglycemia in patients without IV access. Prospective clinical trial. Prehospital in a busy, urban emergency medical services system. Fifty consecutive patients presenting with documented hypoglycemia (ChemStrip BG less than or equal to 80 mg/dL) and symptoms of decreased level of consciousness, syncope, or seizure were enrolled. Data collected included pretreatment (ChemStrip BG) and post-treatment serum glucose (hospital assay) as well as assessment of level of consciousness by a quantitative measure, the Glasgow Coma Score, and by a qualitative scale (0 to 3). The mean pretreatment blood glucose of 33.2 +/- 23.3 mg/dL increased after treatment to 133.3 +/- 57.3 mg/dL. Qualitative level of consciousness increased from a mean of 1.26 +/- .96 to 2.42 +/- .94 and Glasgow Coma Score increased from a mean of 9.0 +/- 4.19 to 13.04 +/- 3.68. The mean time until response was 8.8 minutes in those who responded to both level of consciousness criteria 82% (41 of 50). Glucagon administered for hypoglycemia resulted in a glucose increase in 98% (49 of 50) with headache as the only side effect noted in 4% (two of 50) of patients (P less than .0001). Glucagon is safe and effective therapy for hypoglycemia in the prehospital setting.

Effect of retinoic acid deficiency on in vivo and in vitro GH responses to GHRH in male rats. Retinoic acid has recently been shown to increase growth hormone (GH)-gene transcription rate and GH synthesis in vitro. To investigate the role retinoic acid plays in the neuroregulation of GH secretion we have studied GH responses to growth hormone-releasing hormone (GHRH) in retinoic acid-deficient rats. Compared to normally fed male rats, retinoic acid-deficient rats showed a marked impairment in body weight, which was statistically significant after 3 weeks and maximal after 5-6 weeks (p less than 0.001). Yet, in vivo GH responses to different doses of GHRH (1, 5 and 25 micrograms/kg) in pentobarbital-anesthesized rats were similar in both groups. Also, in vitro GH responses to GHRH, forskolin, and KCl were similar in perfused pituitary cells taken from control and retinoic acid-deficient rats. However, further studies carried out in freely-moving rats showed the typical GH secretory pattern usually found in male rats of the control group, while retinoic acid-deficient rats displayed a highly variable GH secretory pattern with GH peaks of much lower amplitude. Finally, after gel electrophoresis of in vitro 35S-labelled proteins, no differences were observed in the molecular forms of GH. Considering these findings on normal pituitary responsiveness and alterations in GH pulsatility, our data suggest that retinoic acid deficiency leads to an alteration in the neuroregulation of GH secretion at the central level.

[Inhibition of skin test by astemizole]. For the purpose of evaluating the curative effect of antihistamines, we have set up an assay method called the "Skin Test Inhibition Index" (STII). Twenty cases of hay fever were selected for astemizole administration, 10 mg/d for 7 days. Skin titration test were carried out before and after treatment. Significant inhibition of skin test by astemizole was found with STII 91. Another group of 6 hay fever patients was given astemizole 10 mg/d for 10 days. STII was determined on the 5th and 10th days and also on the 7th, 14th and 21st days after treatment. STII were 12, 108, 90, 10 and 7 respectively. These results clearly demonstrated that astemizole is a long-acting antihistamine.

Comparison between high-field-strength MR imaging and CT for screening of hepatic metastases: a receiver operating characteristic analysis. The diagnostic performance of high-field-strength magnetic resonance (MR) imaging (1.5 T) for detection of liver metastases was compared with that of computed tomography (CT). All patients (n = 52) underwent preoperative screening for metastases by means of MR imaging with T1-weighted, proton-density-weighted, and T2-weighted pulse sequences and CT scanning with unenhanced, incremental dynamic bolus-enhanced, and delayed contrast medium-enhanced techniques. Diagnostic performance was evaluated by means of receiver operating characteristic analysis in which 800 images (400 with and 400 without lesions) and five readers (4,000 observations) were used; images were obtained from patients (n = 39) in whom the same anatomic levels were available for all MR imaging and CT studies. Direct comparison between the best MR imaging technique (T2-weighted spin-echo imaging [repetition time, 2,000 msec; echo time, 70 msec]) and the best CT technique (incremental dynamic bolus CT) showed a strong trend of superiority of T2-weighted MR imaging over incremental dynamic bolus CT. No highly statistically significant difference (P greater than or equal to .01), however, was found between these two techniques.

Optical spectroscopy (INVOS) is unreliable in detecting breast cancer. Recently a new nonionizing, nonimaging technique for evaluating risk of breast cancer, in vivo optical spectroscopy (INVOS), became available. The procedure evaluates the biochemical composition of the breast with spectrophotometry to provide a risk number related to the development of breast cancer. INVOS was evaluated in a prospective study of 180 women who were referred to our institution for needle localization and excisional biopsy of 181 breast lesions. All women had mammography and INVOS before surgical biopsy. The INVOS risk numbers and mammographic findings were compared with the pathologic diagnoses. Of 39 breast cancers, 19 (49%) had high-risk INVOS numbers, as did 52% of women with benign disease. INVOS had a sensitivity of 95%, specificity of 4%, and a positive predictive value of 21% for the detection of breast cancer. Mammography predicted malignancy with a sensitivity of 97%, specificity of 48%, and a positive predictive value of 34%. Receiver-operating-characteristic (ROC) curve analysis also was performed. The ROC area for mammography was 0.85 compared with 0.43 for INVOS, indicating a significantly greater (p less than .0000001) ability for mammography to detect breast cancer. We conclude that because INVOS cannot accurately predict the presence of breast cancer, it is unlikely that INVOS can be used to predict which patients are at risk for the development of breast cancer.

Physiological and immunopathological consequences of active immunization of spontaneously hypertensive and normotensive rats against murine renin. Spontaneously hypertensive Okamoto-strain rats (SHR) and normotensive Wistar-Kyoto (WKY) rats were actively immunized with mouse renin to investigate the effect on blood pressure of blocking the renin-angiotensinogen reaction. Ten male SHR and 10 male WKY rats were immunized with purified mouse submandibular gland renin. Control rats were immunized with bovine serum albumin. Antirenin antibodies were produced by both SHR and WKY rats, but renin-immunized SHR had higher titers of circulating renin antibodies after three injections. The increase in renin antibody in renin-immunized SHR was associated with a significant drop in blood pressure (tail-cuff method) that became similar to that of the WKY control rats after four injections. The blockade by antirenin immunoglobulins of the renin-angiotensinogen reaction also decreased the blood pressure of normotensive rats. Perfusion of renin-immunized rats with mouse submandibular renin (10 micrograms) in vivo caused no increase in blood pressure. Perfusion of renin-immunized, salt-depleted SHR with converting enzyme inhibitor caused no further decrease in blood pressure but significantly decreased blood pressure in salt-depleted control rats. The presence of circulating renin antibodies was associated with low plasma renin activity (0.31 +/- 0.23 ng angiotensin I [Ang I]/ml/hr). Plasma renin activity was unchanged in control animals (13.1 +/- 3.9 ng Ang I/ml/hr in control SHR, 13.9 +/- 3.2 ng Ang I/ml/hr in control WKY rats). Renin antibody-rich serum produced a dose-dependent inhibition of rat renin enzymatic activity in vitro. The chronic blockade of the renin-angiotensinogen reaction in renin-immunized SHR produced an almost-complete disappearance of Ang II (0.8 %/- 7 fmol/ml; control SHR, 30.6 +/- 15.7 fmol/ml) and a 50% reduction in urinary aldosterone. Renin immunization was never associated with a detectable loss of sodium after either 10 or 24 weeks. The glomerular filtration rate was not decreased 10 weeks after renin immunization, whereas blood pressure was significantly decreased, plasma renin activity was blocked, and renal plasma flow was increased. The ratio of left ventricular weight to body weight after 24 weeks was significantly below control levels in renin-immunized WKY rats and SHR. Histological examination of the kidney of renin-immunized SHR showed a chronic autoimmune interstitial nephritis characterized by the presence of immunoglobulins, mononuclear cell infiltration, and fibrosis around the juxtaglomerular apparatus. These experiments demonstrate that chronic specific blockade of renin decreases blood pressure in a genetic model of hypertension in which the renin-angiotensin system is not directly involved.(ABSTRACT TRUNCATED AT 400 WORDS)

[Experience with the electrocardiographic diagnosis of cardiac ventricular hypertrophy by the methods of mathematical statistical analysis]. A new index in the diagnostics of right ventricular hypertrophy: AQRS + 52 less than or equal to 235 is derived by means of the discriminant multifactorial analysis and processing the elements of 488 electrocardiograms in the 12 routine leads in 269 deceased. AQRS is the electric heart axis in the frontal plane, determined by Pis'menji tables; Z is the transitory zome in precordial leads, expressed with tenfold increased number of the lead, e.g. V1-10, V2-20 etc. In case of transitory zone between two leads, e.g. V4-V5-the interpolated value between 40 and 50 is indicated-i.e. 45. The new index as compared with selected 18 basic indices for right ventricular hypertrophy is with considerably better diagnostic qualities: sensitivity--84%, false positiveness 13% and diagnostic accuracy 86%.

Present management of hepatic artery aneurysms. Symptomatic left hepatic artery aneurysm; right hepatic artery aneurysm with erosion into the gallbladder and simultaneous colocholecystic fistula--a report of two unusual cases and the current state of etiology, diagnosis, histology and treatment. A left hepatic artery aneurysm has an incidence of 0.8% among the splanchnic artery aneurysms. 20% of splanchnic artery aneurysms are hepatic artery aneurysms. Atherosclerosis (32%) is the most prevalent etiology, followed by trauma (22%) and inflammatory lesions (10%). The average age is 40 (10-83) years, the male to female ratio 2:1. In 64-80% of cases rupture of the aneurysm is the first clinical manifestation. The mortality is then about 35%. The case of a 64 years old female with a symptomatic aneurysm of the left hepatic artery and the case of a 70 years old female, who underwent emergency laparotomy for acute colorectal hemorrhage, with a right hepatic artery aneurysm, which perforated into the gallbladder, with simultaneous colocholecystic fistula is reported and the etiology, histology, and present diagnostic and therapeutic management of hepatic artery aneurysms is discussed.

Determination of bromazepam in plasma with an internal standard by gas-liquid chromatography. A gaschromatographic assay method is described for the determination of Ro 5-3350 (bromazepam) using Ro 5-4547 (methylbromazepam) as internal standard. After alkaline ether extraction the bromazepam and methylbromazepam obtained from sulfuric acid reextraction are hydrolyzed to ABBP and to MABBP, respectively. After neutralization, the bromo-pyridine-benzophenones are extracted with ether and dissolved in hexane after evaporation of the ether. Under the described gaschromatographic conditions it was found that MABBP and ABBP have retention times of 10.5 and 12.5 min, respectively. The limit of sensitivity is situated at 5 ng/ml of plasma. The specificity is satisfactory since the metabolite which might have interfered (hydroxy-3-bromazepam) appears only at very low concentrations in the blood. The linearity of the calibration curve was confirmed for plasma concentrations up to 100 ng/ml.

[Diagnostic relevance of provocative (evocative) blood enzyme tests in pancreatic disease (author's transl)]. After a review of the literature the author's results of testing pancreatic function in 445 patients with different diseases are reported. The activities of serum amylase and lipase were estimated before and after stimulation with secretin and pancreozymin; at the same time exocrine secretions of the pancreas were collected in the duodenum and analyzed. Serum enzyme activity did not change markedly after stimulation in pronounced pancreatic insufficiency. Measuring the enzyme activity thus helped to make the diagnosis only in a few cases with chronic pancreatitis and pancreatic carcinoma. In all other patients there was no correlation between changes of serum enzyme activities and changes of exocrine pancreatic function. Pathological test results, that means an increase in enzyme activity after stimulation, were found not only in patients with established or suspected pancreatic diseases, but also in many other subjects. Thus the diagnostic relevance of these tests seems to be rather limited, since it does not prove or exclude with sufficient specificity or adequate probability the presence of pancreatic diseases; it therefore cannot be recommended for screening purposes.

Comparative studies on the '5'-cap' and in vitro translational activity of cytoplasmic and nuclear poly A(+) RNA1. The translational activities of cytoplasmic poly A(+)RNA of normal rat liver and Novikoff hepatoma cells in the wheat germ cell free system were found to be approximately 15-20 times greater than tose of the corresponding nuclear poly A(+) RNA. The translationsl activities were 85 and 62 pmoles 3H-leucine incorporated/micron g cytoglasmic poly A(+) RNA for the liver and tumor respectively and 3-4 pmoles 3H-leucine incoporated/micron g nuclear poly A(+)RNA. Inasmuch as intergity of the '5'-cap' of mRNA is essential for its translational activity, quantitative comparisons were made of its content in these RNA fractions. Of the total 32P incorporated into the tumor cytoplasmic poly A(+) RNA, 0.41% was in the '5'-cap'; in nuclear poly A(+) RNA, the '5'-cap' contained 0.11%. After periodate oxidation and labeling with KB3H4, m7 guanosine, the 5'-terminal nucleoside in both liver and Novikoff hepatoma nuclear poly A(+) RNA contained approximately 20% as much isotope as in the cytoplasmic poly A(+) RNA. These results suggest the lower translational activity of nuclear poly A(+) RNA is partly related to its lower content of the '5'-cap'. Molecular selection of poly A(+) RNA for transport out of the nucleus or further cytoplasmic processing may account for the higher percentage of the '5-cap' and the greater translational activity of the cytoplasmic poly A(+) RNA. During these studies, it was also found that the m7 guanosine of the '5'-cap' was not removed during translation of the mRNA in the wheat germ system; this result suggests that the '5'-cap' may associate with allosteric binding sites of initiation factor(s).

The perception of emotion by schizophrenic patients. Studies which have examined the perception of emotion by schizophrenic patients have produced conflicting results, an outcome which may, in part, be due to difficulties in presenting a realistic portrayal of emotion. This study exposed 32 schizophrenic patients in remission and ten controls to five videotaped scenes of emotional situations played by actors. The schizophrenic patients were divided into three groups, namely those living with high-EE relatives, those living with low-EE relatives and those living alone, in order to test the hypothesis that patients in a high-EE environment are less able to identify emotionally charged situations. Measures of electrodermal activity and self-ratings of tension were recorded concomitantly. The schizophrenic patients in all groups were as adept at identifying emotions as were the controls. There was no difference between the groups in electrodermal activity and subjective tension for all video scenes, except for the one which portrayed the only pleasant interaction; the high-EE group was significantly more aroused on both measures, which were independent of each other.

A novel technique for immunohistoperoxidase staining of unfixed whole joints of small animals. A method has been developed to cut unfixed and undecalcified sections of rat paws from animals with adjuvant arthritis and to stain them by a biotin-avidin immunoperoxidase technique. Good tissue integrity and morphology throughout the immunohistochemical procedure were retained if the sections were first mounted on transparent sellotape. The method is illustrated with two monoclonal antibodies (mAb) and is generally applicable with any mAb or polyclonal antibody and with joints from other small animals. For rats with adjuvant arthritis it was found important to block endogenous peroxidase before immunostaining. Complete inhibition of this enzyme without loss of antigenicity was best achieved after application of the mAb and biotinylated anti-IgG conjugate to the unfixed tissue sections.

[Therapeutic indications of low molecular weight heparins]. The depolymerisation of the various chains of unfractionated heparin (UFH) by chemical or enzymatic reactions provides so-called low molecular weight heparin (LMWH), with an average molecular weight of approximately 5000 daltons. The specific biological and pharmacokinetic properties of LMWH with greater inhibition of factor Xa than of thrombin activity, less interaction with platelets, better bioavailability and a longer half life of anti-Xa activity, suggest possible new therapeutic applications. The hypothesis of reducing the risk of haemorrhage related to the antithrombin activity and the incidence of heparin-induced thrombocytopenia whilst preserving effective antithrombotic action has stimulated clinical and biological research. Clinical trials of prophylaxis of venous thrombo-embolism have been undertaken mainly in surgical patients. The results have shown identical if not better efficacy of LMWH compared to UFH in general surgical and above all orthopedic patients in whom subcutaneous heparin is only effective with a strict protocol which is difficult to adhere to in routine practice (adaptation of dosage to activated partial thromboplastin time). The risk of bleeding was not significantly lower using LMWH at the specified dosage, which in the latter indication, is twice that used in general surgery. There are many indications of prophylaxis of thromboembolism in the medical specialties but, paradoxically, LMWH has not been widely studied because of the difficulties in performing the therapeutic trials. Except in rare cases (extreme body weights, renal failure, haemorrhagic disease, thrombotic or haemorrhagic complications) the evaluation of amidolytic anti-Xa activity does not seem to be necessary. More recently, LMWH has been studied in a small number of trials for the treatment of deep venous thrombosis (DVT). The therapeutic efficacy is identical if not better than that of UFH without increasing the risk of bleeding. Biological monitoring seems to be necessary in this indication for evaluating amidolytic anti-Xa activity, which, though not a true marker of antithrombotic activity is a relatively sensitive investigation. The therapeutic values are 0.5 IU/ml to 1.0 IU/ml, 3 to 4 hours after subcutaneous injection. The conclusions of all these trials are: LMWH is relatively simple to use and, compared with UFH, has a more stable anticoagulant effect due to its pharmacokinetic properties; the therapeutic efficacy is as good as, if not better, than that of UFH; the risk of bleeding remains, therefore, the specified dosages should be respected and treatment should be monitored by anti-Xa activity when indicated; the decreased interaction with platelet function should not mask the risk of thrombocytopoenia.(ABSTRACT TRUNCATED AT 400 WORDS)

Treatment of adult varicella with oral acyclovir. A randomized, placebo-controlled trial. To assess the efficacy of oral acyclovir in treating adults with varicella and to describe the natural history of adult varicella. Double-blind, placebo-controlled randomized trial. A naval hospital. One hundred forty-eight of 206 consecutive adult active duty Navy and Marine Corps personnel who were hospitalized for isolation and inpatient therapy of varicella and who could be treated within 72 hours of rash onset completed the study. The diagnosis of varicella was confirmed by acute and convalescent serology in 143 of 144 patients with available paired sera. Patients were randomly assigned to receive either acyclovir, 800 mg orally five times per day for 7 days, or an identical placebo. Separate randomization codes were used for patients presenting within 24 hours of rash onset and for those presenting 25 to 72 hours after rash onset. Daily lesion counts, symptom scores, temperature measurements, and laboratory tests were used to monitor the course of the illness. Early treatment (initiated within 24 hours of rash onset) reduced the total time to (100%) crusting from 7.4 to 5.6 days (P = 0.001) and reduced the maximum number of lesions by 46% (P = 0.04). Duration of fever and severity of symptoms were also reduced by early therapy. Late therapy (25 to 72 hours after rash onset) had no effect on the course of illness. Only four patients had pneumonia, and no encephalitis or mortality was noted. Early therapy with oral acyclovir decreases the time to cutaneous healing of adult varicella, decreases the duration of fever, and lessens symptoms. Initiation of therapy after the first day of illness is of no value in uncomplicated cases of adult varicella. The low frequency of serious complications of varicella (pneumonia, encephalitis, or death) precluded any evaluation of the possible effect of acyclovir on these outcomes.

Auditory brainstem responses elicited by 1000-Hz tone bursts in patients with sensorineural hearing loss. Auditory brainstem responses were measured in response to 1000-Hz tone bursts from 115 patients with sensorineural hearing loss, presumably of cochlear origin. Mean wave V latencies and variability were comparable to those observed in normal hearing subjects for similar stimuli. The range of interaural differences in wave V latencies for 1000-Hz tone bursts were slightly greater than those observed for clicks, which may not be surprising, given the greater variability in wave V latencies for tonal stimulation, even in normal-hearing subjects. These differences, however, were not affected either by the magnitude or symmetry of hearing loss for frequencies at and above 1000 Hz. These data suggest that tone burst ABRs might be useful in otoneurologic evaluations, especially for patients with asymmetric hearing loss.

Interference of a synthetic C18 juvenile hormone with mammalian cells in vitro. II. Effects on cell cycle. Interference of a synthetic C18 juvenile (JH) with the cell cycle of mouse embryo cells (ME-cells) and mouse cells of established cell line (L-cells) was examined. After 3 hour in the medium with JH (20 mg/ml) the cells were transfered to the regular culture medium and labelled with H3-thymidine then incubated for 1 to 48 hours before processing them for autoradiography. The percentage of labelled mitosis was then calculated for all cells samples examined and the labelled mitosis curves were drown and analyzed. It was shown that in contrast to the solvent which had no effect on duration of any of the component phases of the cell cycle of ME-cells, the juvenile hormone under conditions of these experiments prolonged G1 and G2 intervals what resulted in prolongation of the total cell cycle of these cells. On the other hand it shortened G1 and prolonged G2 intervals of L-cells without changing duration of the total cell cycle. Thus, in the examined mouse cells, they were the G1 and G2 intervals which are affected by JH. This findings are considered as an argument for pleiotropic nature of the juvenile hormone interference with mouse cells, the more so as it interfered with both protein and DNA synthesis in these cells.

Use of polyethyleneglycol-treated serum for animal cell cultures. Although many proteins will be removed from sera by precipitation with 10% polyethyleneglycol (PEG) the growth-promoting properties of such PEG-treated sera for many cell lines and cell strains are hardly reduced. Among the precipitated proteins are the macroglobulins which are difficult to remove from cell cultures and which may cause allergic reactions if incorporated into vaccines. The gammaglobulins are removed in this way as well. If the sera are contaminated with viruses or phages the titres will be reduced by approximately 4 logs and thus the incidence of virus contamination will be reduced by the PEG-treatment. For foot-and-mouth Disease (FMD) vaccine production PEG-treated sera from vaccinated cattle were applied for cell and virus cultivation. The virus obtained was subsequently precipitated with PEG and collected by filter-aid filtration. A concentrated virus product was obtained, which was practically devoid of serum proteins.

The mechanism of action of cholera toxin in pigeon erythrocyte lysates. The adenylate cyclase activity of intact pigeon erythrocytes begins to rise after about 20 min of exposure to cholera toxin. The maximum rate at which the cyclase activity increases appears to be limited by the number of toxin molecules which can reach an intracellular target. If the erythrocytes are made permeable to the toxin by a bacterial hemolysin, no such limit exists, and adenylate cyclase activity starts to rise immediately upon the addition of toxin, and continues to rise to a maximum at an initially constant rate which is dependent upon the concentration of toxin. On lysed erythrocytes, the addition of cholera antitoxin immediately prevents any further rise in adenylate cyclase activity, but does not reverse any activation already achieved. Erythrocyte lysates may also be activated by isolated peptide A1 of cholera toxin, although activation of adenylate cyclase of intact erythrocytes requires the complete toxin molecule. In the intact cells, toxin first attaches by its Component B to surface receptors of which there are about 30 per erythrocyte. Subsequently, peptide A1 but not Component B is inserted into the erythrocyte. It takes only about 1 min at 37 degrees for peptide A1 to be sufficiently deep within the cell membrane to be inaccessible to extracellular antitoxin, but its complete transit through the membrane appears to take longer. The surface receptors are used only once, for they remain blocked by Component B. The number of receptors available on the surface may be increased by soaking cells in ganglioside GM1. Cholera toxin also decreases the rate of apparently spontaneous loss of adenylate cyclase activity and increases the response to epinephrine. Theophylline inhibits the action of cholera toxin.

Bactericidal activity of daptomycin against vancomycin-resistant Enterococcus faecium in an in vitro pharmacokinetic model. A dynamic in vitro model was used to determine the killing kinetics of daptomycin against 15 vancomycin-resistant clinical isolates of Enterococcus faecium. Concentration profiles simulating those observed in serum following administration of both low-dose (2 mg/kg) and high-dose (6 mg/kg) daptomycin were bactericidal within 5.5 and 2.8 h, respectively. In contrast, when albumin was added to the growth medium, the corresponding bacterial killing times were slowed to greater than 24 h and 7 h; these results suggest that in the clinical setting, daptomycin dosages of approximately 6 mg/kg are required to achieve bactericidal activity against vancomycin-resistant Enterococcus faecium.