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201 | The cardiac cycle and the effects of neurohumors on myocardial contractility in the Asiatic eel Anguilla japonica, Timm. & Schle. | |
202 | Characteristics of the noradrenergic innervation of the left atrium in the chick (Gallus gallus domesticus, L.). | |
203 | Responsiveness of neurogenic hearts to octopamine. | |
204 | Action of kainic acid on a glutamatergic synapse. | |
205 | The effects of 5-hydroxytryptamine depletors and monoamine oxidase inhibitors on color changes of the fiddler crab, Uca pugilator: further evidence in support of the hypothesis that 5-hydroxytryptamine controls the release of red pigment-dispersing hormone. | |
206 | Evidence of a gastrin-like substance in Rhinobatus productus. | |
207 | 5-hydroxytryptamine as a possible inhibitory neurotransmitter in the central nervous system of the leech, Haemopis sanguisuga. | |
208 | Gastrin-like activity in an Indian python. | |
209 | Kinetics of antibody--hapten reactions. | |
211 | Effects of maleate on renal reabsorption of bicarbonate. | |
212 | Bicarbonate inhibition of rat kidney aconitate hydratase isoenzymes. | |
210 | Influence of pH and hypoxia on the success of defibrillation. | Clinical impressions about the problem of defibrillation during states of acid-base imbalance and hypoxia have been influenced by studies involving the effect of these derangements on the ventricular fibrillation threshold. Based on body weight, energy requirements for defibrillation in normal dogs were compared to requirements in dogs subjected to commonly encountered acid-base disturbances and severe hypoxemia. No significant differences were found. Seventy-five percent of all animals in the study were electrically converted with low-to-moderate levels of energy. The incidence of spontaneous resumption of circulation following defibrillation was lowest in animals subjected to metabolic acidosis and hypoxia. The results suggest that pH and blood gas alterations, previously shown to influence the normal ventricular fibrillation threshold, do not significantly affect the normal defibrillation threshold. |
213 | Metabolic studies in experimental renal dysfunction resulting from maleate administration. | |
214 | Multiple endocrine adenomatosis-I and II. | |
215 | A randomized double-blind study of timolol in patients with essential hypertension. | |
216 | [Observation of permanent teeth adjacent to teeth damaged by trauma]. | |
217 | Idiopathic hypertrophic subaortic stenosis (hypertrophic obstructive cardiomyopathy) changing concepts-1975. | |
218 | Pleural effusion associated with aortitis syndrome. | A patient with aortitis syndrome had a pleural effusion which subsided but reappeared with an exacerbation of aortitis symptoms while under antituberculosis treatment. The character of the fluid was that of an exudate, and the glucose concentration was normal. Clinical and laboratory features of the case suggest that the effusion was part of the aortitis syndrome per se. |
219 | The metabolic fate of securinine. | |
220 | [Transplantation and preservation of tissue-typized skin in burns]. | At the Department of Plastic Surgery and Burns, Berufsgenossenschaftliche Unfalklinik Ludwigshafen-Oggersheim, a skinbank with typed skin has been established. The storage system consists of deep-freezing at -196 degrees C in liquid nitrogen. The transplantation of HL-A typed skin was evaluated from the clinical and histological point of view. Due to the effort necessary for such an undertaking this method is critically reviewed. |
222 | [Ability of antilymphocyte sera to counteract the allogeneic inhibition of hematopoietic stem cells]. | |
223 | [Microenvironment of enzymes as 1 of the factors determining enzyme stability. Stabilization of soluble and immobilized horseradish peroxidase]. | |
224 | [3d regional meeting of the specialty field of supervisory nurses in Baden-Württemberg, Northern Group. June 25, 1975 in district hospital Heidenheim]. | |
221 | [Polyploidization and fusion of insect cells exposed to concanavalin A]. | |
225 | [Adverse effects of anti-epileptic drugs]. | |
226 | Charge properties of human pituitary and amniotic fluid prolactins. | The apparent isoelectric points (pI) in isoelectric focusing (IF) of human pituitary and amniotic fluid prolactin (hPRL), both non-iodinated and iodinated, were determined. Unresolved mixtures of pituitary hPRL isohormones E and F, and of at least five isohormones found in amniotic fluid, and plasma hPRL exhibit an average pI value of 6.5 - 6.7. Transient state pH values observed or previously reported for hPRL components range from pH 5.9 to 6.8 after correction to standard conditions. At pH 8.1, the major isohormone, hPRL-F, carriers a charge of 2.2 net protons per molecule. The net charge differences among isohormones E, F and G are compatible with acquisition or loss of single charged groups per 20,000 molecular weight. This net charge is similar to that of the least prolactin-bioactive major isohormone of human growth hormone (hGH-B), while the hGH with a bioactivity comparable to that of hPRL exhibits a net charge of 3.4 valence units. The "large" isohormones J and H increased net charges, by a factor of 2-3, in direct proportion to their size increments. |
227 | Human and monkey prolactin and growth hormone: separation of polymorphic forms by isoelectric focusing. | The feasibility of using isoelectric focusing for the separation of primate pituitary growth hormone from prolactin and for the characterization of polymorphic forms of these hormones was explored. In a pH 3--10 gradient, extracts of both human and cynomolgus monkey pituitaries were each resolved into 4 growth hormone components and at least 3 prolactin components, as shown by radioimmunoassay. In narrower gradients (of 2--3 pH units) greater resolution was achieved; the principal growth hormone components were well separated from the principal prolactin components but there was overlapping of some minor components. A partially purified human prolactin preparation was found to contain 4 prolactin components, one of which had a prolactin/growth hormone ratio of 760. Clinical grade human growth hormone was also resolved into at least 5 prolactin and 5 growth hormone components, many of which had higher pI values than those found in pituitary extract. Under the conditions used, both growth hormone and prolactin were found to be polymorphic with respect to isoelectric point. Some of the human prolactin components were found to contain less than 0.2% growth hormone by radioimmunoassay. Monkey growth hormone containing 0.01% prolactin was isolated. These findings demonstrate that isoelectric focusing is useful for the preparation of both growth hormone and prolactin which are essentially free of one another. Furthermore, the polymorphic forms were repeatedly found in preparations obtained by several methods and from 2 different species, suggesting that these forms are not artifacts. |
228 | The interaction of SO2 with proteins. | |
229 | Ecological observation of the 137Cs-contamination in beef of animals from the southern-Bavarian area. | Certain climatic and edaphic conformations in the Bavarian sub-alpine mountains and in the Alps favor above all the development of a land utilization system and farm structures similar to those in the northern part of Scandinavia. In 1963/64, the years of the highest environmental contamination up to the present, we established in 600 beef samples from the round or shoulder of male and female cattle (mainly Highland cattle) close connections between the 137Cs-contamination of green crop and the long lastnig yearly precipitation quantities, as well as certain relations between the 137Cs-contamination of meat and differences in the feeding and keeping of the animals. During summer-seasons (April-October), beef of cattle from pastures with heavy rainfall (Alps) was contaiminated by 137Cs up to 15 times more than that of confined animals. Hereby the rate of 137Cs-contamination in the meat of grazing cattle was nearly proportional to the quantities of precipitation. When confined cattle were fed on pastures in autumn after harvesting for 2 to 3 weeks, a quick increase of 137Cs-contamination of the meat was caused within this time up to values which in this district were otherwise only observed in grazing cattle. The lower 137Cs-content in meat of cattle housed during the summer season is due to the more varied fodder, which is at that time less contaminated than green crop. During the winter season (November to March), the highest contaminations in the meat of confined (Bohemian Forest) or grazing cattle (Alps) was measured when the animals in these districts were almost exclusively fed with fodder from the own farmground or with leafy silage. The highest contamination was almost regularly noticed in January, February and March, as generally during these months the highly contaminated first cut hay is fed. Here the meat was often even more contaminated than that of grazing cattle. After the quick decrease of 137Cs in fallout noticed in the years 1964 and 1965, in 1965/66 a dependance in the 137Cs-contamination of beef on the methods of keeping and feeding could still be observed in only the extreme cases (Alps, Bavarian- and Bohemian Forest); though in general, meat of animals from districts with heavy rainfall was slightly more contaminated than meat of animals from regions with less precipitation. |
230 | Liver microsomal beta-glucuronidase and UDP-glucuronyltransferase. | Both UDP-glucuronyltransferase (GT) and beta-glucuronidase (betaG) were assayed in untreated liver microsomes. Optimum assay conditions were established with rat liver microsomes using p-nitrophenol (pNP) and its glucuronide (pNPGA) at the pH optima of GT (7.5) and betaG (4.5). The activities of the two enzymes were compared using microsomes from rats, mice, pigs, cattle and horses, with pNP, pNPGA, and phenolphthalein as substrate, in the presence of various cofactors and inhibitors at pH 7.5 and 4.5. These data disclose pronounced differences with respect to species, substrate and other experimental conditions, thereby precluding the establishment of general optimum conditions. The two enzymes were also assayed under strictly identical conditions using pNP and pNPGA and rat liver microsomes at pH 7.5 in the presence and absence of UDP-glucuronate disodium (UDPGA), activators (ATP;UDP-N-acetylglucosamine) and inhibitors. When provided with a functional level of UDPGA, both enzymes proved active under those conditions, and a conjugation-deconjugation interplay was indicated. The two processes could be selectively and totally inhibited by Zn2+ and saccharolactone. The results suggest that conjugation-deconjugation-reconjugation cycles may be operative in the metabolism of drugs in vivo, taking place already at the level of the liver endoplasmic reticulum. |
231 | Biochemical aspects of renal ammonia formation in metabolic acidosis. | In omnivorous creatures, the diet is acidogenic, especially as a result of the meat content, which gives rise to phosphoric and sulphuric acids, i.e., to metabolic acidosis. In the short term, metabolic acids are buffered by tissue proteins and bicarbonate (the 'alkali reserve'). In the longer term, acid must be excreted, or neutralized with base which is also generated from the diet, by conversion of dietary amino-nitrogen to ammonia. The final steps of this process occur in the kidney, which converts circulating glutamine to ammonia, and to carbon products such as glucose and carbon dioxide, by metabolic reactions which adapt during acidosis to generate more ammonia and maintain an increased renal ammonia content. The complex mechanisms which govern the formation of ammonia, glucose and carbon dioxide from glutamine, involving the reactions of amino acids, the tricarboxylic acid cycle, and gluconeogenesis, are reviewed. |
232 | Studies on the mechanism of the changes in serum and liver gamma-glutamyl transpeptidase activity. I. Experimental extrahepatic cholestasis in rabbits. | Serum, liver and renal gamma-glutamyl transpeptidase (GGT) activities were studied in four groups of rabbits: controls, rabbits with obstructive extrahepatic cholestasis, rabbits with obstructive anuria, and animals with combined obstructive extrahepatic cholestasis and obstructive anuria. Serum GGT was essentially increased in rabbits with obstructive extrahepatic cholestasis, showing peak values in the combined cholestasis + obstructive anuria group, and practically normal values in animals with anuria. Liver GGT was increased in both cholestasis groups, but the increase was less prominent than the increase in serum GGT and there was no correlation between them. In both anuric groups renal GGT was reduced, probably as a result of inhibited enzyme synthesis secondary to the altered conditions for adequate renal function. The results obtained are suggestive of a probable renal involvement in the formation of the serum GGT activity level. |
233 | Studies on the mechanism of the changes in serum and liver gamma-glutamyl transpeptidase activity. II. Experimental hexachlorobenzene porphyria in rabbits. | The mechanism responsible for the changes in serum and liver gamma-glutamyl transpeptidase (gamma-GT) activity was studied in a model of experimental hexachlorobenzene porphyria in rabbits. Porphyria followed the administration of hexachlorobenzene in doses of 280 mumol - kg-1 body weight, which were given daily through a gastric tube over a 20-day period. Serum gamma-GT activity and the activities of the lysosomal enzymes beta-N-acetylglucosaminidase and alpha-mannosidase were increased, whereas L-aspartate: 2-oxoglutarate aminotransferase and L-alanine: 2-oxoglutarate aminotransferase and L-alanine: 2-oxoglutarate aminotransferase remained unaltered. There was a considerable increase in liver microsomal protein, gamma-GT, cytochrome P-450, anilinehydroxylase, aminopyrine-demethylase and delta-aminolevulinic acid synthase. In the liver gamma-GT was detected in the microsomes as well as in the cytoplasm where enzymatic activity was higher. The high correlation coefficient between liver gamma-GT, cytochrome P-450 and delta-aminolevulinic acid synthase witnesses a hexachlorobenzene-induced gamma-GT formation in the liver. A statistically significant correlation between serum and liver gamma-GT activity was also found. These data strongly suggest that the increase in serum gamma-GT activity may result from the induction of the enzyme in the liver. |
234 | Changes in erythrocyte 2,3 diphosphoglycerate in women following short term maximal exercise. | 15 untrained women were subjected to a walking treadmill test to determine the influence of maximal exercise upon synthesis of erythrocyte 2,3 DPG. Although there was a 9.8% increase in the 2,3 DPG content following exercise, there was a concomitant 9.4% increase in the hemoglobin level; therefore, when 2,3 DPG is expressed as a ratio to hemoglobin (See Article), there was no significant change as a result of exercise stress. It was suggested that three additive factors produced during strenuous exercise; decreased pH; increased hemoglobin concentration; and increased CO2 production result in by-product inhibition of 2,3 DPG synthesis. It is concluded that 2,3 DPG does not provide a physiologic benefit in the adaptation of the oxygen transport system to exercise. |
235 | Hydroxylation of p-Coumaric acid by illuminated chloroplasts. The role of superoxide. | 1. Chloroplasts isolated from leaves of spinach-beet (Beta vulgaris L. ssp. vulgaris) do not catalyse the hydroxylation of p-coumaric acid in the dark unless a reductant (such as ascorbate, NADH or NADPH) is added. Superoxide dismutase has no effect on this reaction. 2. Illuminated chloroplasts catalyse the hydroxylation in the absence of added reductant. This reaction is completely inhibited by superoxide dismutase, but catalase has little effect. 3. Both hydroxylation in the light and hydroxylation in the dark in the presence of reductants are inhibited by diethyldithiocarbamate, EDTA, cyanide and 2-mercaptoethanol. 4. It is proposed that O-2- generated by illuminated chloroplasts is involved in the provision of a reductant to the enzyme phenolase. |
236 | Identification of chloride-binding sites in hemoglobin by nuclear-magnetic-resonance quadrupole-relaxation studies of hemoglobin digests. | 35Cl minus-nuclear magnetic resonance (NMR) studies indicate that various digests of human hemoglobin with carboxypeptidase A and B, or a combination of the two, may be used for the identification of chloride binding sites. All the digestion products contain, like hemoglobin itself, at least two classes of binding sites, one of high, the others of low affinity. The pH dependence of the excess linewidth of the 35Cl minus NMR signal indicates that in the simple digests with either carboxypeptidase A or B, chloride is bound with high affinity at or near His-beta146-Asp-beta94 and at or near Val-alpha1-Arg-alpha141. The high-affinity sites show, in the case of the simple digests, a strong oxygen linkage which is lost in the forms digested with both carboxypeptidase A and B; this linkage may thus be correlated to the presence of conformational changes. Organic phosphates, like inositol hexaphosphate, show competition for some of the high-affinity chloride binding sites in hemoglobin and in the simple digests. This competition is likewise lost in the doubly digested hemoglobins. |
237 | The internal-alkaline pH gradient, sensitive to uncoupler and ATPase inhibitor, in growing Clostridium pasteurianum. | 1. The intracellular pH was measured in growing Clostridium pasteurianum with and acid-base equilibrium distribution method. [14C]Dimethyloxazolidinedione, [14]methylamine and [14C]acetic acid were used as "deltapH-indicators". During growth the extracellular pH decreased from 7.1 to 5.1; simultaneously the intracellular pH changed from 7.5 to 5.9. Thus, the intracellular pH was more alkaline than the extracellular pH by 0.4 to 0.8 pH-units. 2. This pH gradient (interior alkaline) was abolished by the proton conductor carbonylcyanide m-chlorophenylhydrazone and the ATPase inhibitor N,N'-dicyclohexylcarbodiimide. The pH gradient could not be demonstrated in cells depleted of an energy substrate. These results suggest that the pH gradient is formed by an ATPase-driven extrusion of protons from the cells rather than by a Donnan potential. 3. Growth of the organism was inhibited by low concentrations of both carbonylcyanide m-chlorophenylhydrazone (5 muM) and dicyclohexylcarbodiimide (5 muM). This finding suggests that the pH gradient is essential for the growing cell as it may be required for substrate accumulation and other types of transport processes. |
238 | D-alanyl-D-alanine carboxypeptidase in the bacterial form and L-form of Proteus mirabilis. | Membranes of the bacterial form and the stable and unstable L-forms of Proteus mirabilis contain LD and DD-carboxypeptidase. The DD-carboxypeptidase is inhibited non-competitively by penicillin G. The enzyme of the bacterial form is highly penicillin-sensitive (Ki - 4 X 10(-9) M penicillin G). Inhibition is only partly reversible by treatment with penicillinase or by dialysis against buffer. In contrast, the DD-carboxypeptidase of the unstable L-form, grown in the presence of penicillin, is 175-fold less penicillin-sensitive (Ki = 7 X 10(7) M penicillin G). Inhibition is completely reversed by penicillinase or dialysis. After inhibition by penicillin and subsequent reactivation the penicillin sensitivity of the bacterial DD-carboxtpeptidase is similar to the sensitivity of the enzyme of the unstable L-form. The hypothesis is proposed that P. mirabilis contains two DD-carboxypeptidases of different penicillin sensitivity and with different mechanisms of penicillin binding. Peptidoglycan synthesis in the cell walls of the unstable L-form is probably carried out with the help of only one DD-carboxypeptidase, viz. the completely reactivatable enzyme with the lower penicillin sensitivity. |
239 | Pigeon-liver NAD kinase. The structural and kinetic basis of regulation of NADPH. | NAD kinase was purified from pigeon liver by an improved procedure which included chromatography on phosphocellulose. The resultant preparation was homogeneous as judged by gel electrophoresis, but electrofocusing gave indications of heterogeneity. The enzyme appeared to be of molecular weight 270000, and to consist of subunits of molecular weight 34000; it may therefore be an octomer. Kinetic studies over a wide range of substrate concentrations revealed departures from Michaelis-Menten behaviour with the substrate NAD+; these were interpreted tentatively in terms of negative homotropic interactions between identical binding sites, since thermal and chemical inactivation studies revealed no evidence for more than one type of catalytic site. The significance of the kinetics and of the type of inhibition produced by NADPH is discussed in terms of the regulation of NAD kinase activity in vivo. |
240 | Hydrogen ion changes and contractile behavior in the perfused rat heart. | The effect of acid-base alterations was analyzed using isolated rat hearts perfused at constant coronary perfusion pressure, and stimulated to contract at constant rat. The amount of shortening in the major axis and its derivative were measured to assess myocardial contractility. Both the 'respiratory' and 'metabolic' alterations affected the contractile behavior to the same extent. In the physiological range studied by us, acidosis depresses and alkalosis increases myocardial contraction. However acidosis seems to depress contractility more than the enhancement produced by the same change in pH towards the alkalotic side. When either amount of shortening or max dl/dt was plotted as a function of hydrogen ion acitvity (aH+) a linear correlation was obtained, either with pure 'metabolic' or 'respiratory' acid-base induced alterations (correlation coefficients higher than -.95; P less than .01). Our findings suggest that in the range studied by us, contraction of the perfused rat heart following acid-base alterations, is a linear function of hydrogen ion activity. |
241 | Changes of EEG and pulmonary venous admixture during a protein load in patients with cirrhosis. | 21 patients with cirrhosis of the liver and 24 control patients were studied before and after a protein load (120 g protein per day during one week). An EEG was recorded and a visual assessment of frequency pattern was performed. Venous admixture was estimated during hyperoxia. According to the EEG frequency pattern the patient group with cirrhosis was subdivided into those with EEG slowing after the protein load (n = 7) and those without (n = 14). The following results were obtained: 1) Resting arterial blood gases did not change in either group. 2) There was a significant increase of the AaD02 (difference between alveolar p02 and peripheral arterial p02) in cirrhotics and controls. 3) The increase in AaD02 was significantly larger in those cirrhotics showing EEG slowing compared to those without EEG - slowing or to the controls. 4) Fractional venous admisture increased significantly in those cirrhotics showing EEG slowing. There was no significant change in those patients who did not show EEG changes or in the controls. |
242 | Formation of fertilization acid by sea urchin eggs does not require specific cations. | |
243 | Primary culture of parenchymal liver cells on collagen membranes. Morphological and biochemical observations. | |
244 | Cell transformation in isolated striated muscle of hydromedusae independent of DNA synthesis. | |
245 | Induction of DNA synthesis by dichloroisoproterenol without initial rise of the cAMP level in the parotid gland of mouse. | |
246 | Cell density-dependent stimulation of glutamine synthetase activity in cultured mouse teratoma cells. | |
247 | Polyadenylation of nascent RNA during the embryogenesis of Ilyanassa obsoleta. | |
248 | The effect of environmental pH upon acid hydrolase activities of cultured human diploid fibroblasts. | |
249 | Enucleation of cells by density gradient centrifugation. | |
250 | An evaluation of factors affecting the in vitro bioassay for erythropoietin. | Two main aspects of the in vitro mouse foetal liver cell assay for Erythroid Stimulating Factor (ESF) in human sera have been investigated. The haem extraction process has been shown to give specific and quantitative recovery of 59Fe labelled haem from haemoglobin thus confirming that the material assayed in human sera is stimulating the synthesis of this protein. The extraction procedure can be simplified considerably by prior mixing of the reagents without significantly influencing the results. Several serum constituents (citrate, testosterone, B12, folic acid and iron) have been investigated over a range of concentrations for possible effects on the cultures. Generally only small effects on haem synthesis were observed. It is concluded that variations in the levels of these factors in sera from treated patients will not produce any significant alterations in the estimated ESF concentrations. |
252 | [Cryptorchism]. | |
251 | [Synthesis of N-substituted isoindolines]. | Some derivatives of isoindoline were prepared in order to test their cardiovascular activity. Pharmacological tests showed that some of the compounds had moderate alpha-blocking and coronarodilatory activity whereas others had some local anesthetic activity. |
253 | [Elements of scientific work organization in ambulance feldshers' functions]. | |
254 | [Participation of feldshers and midwives in the secret and partisan activities during the great patriotic war]. | |
255 | [The organization of health education meetings, verbal reports, carnivals, reader's conferences]. | |
256 | [Problems concerning the training of feldshers in foreign countries]. | |
257 | [Mechanisms of the thermogenic action of noradrenaline during adaptation to cold]. | In white rats both adapted and unadapted to cold, the RQ dynamics during cold exposure, noradrenaline and ganglion blocking agent administration, were studied. The adapted animals' RQ in thermoneutral conditions was shown to be a little higher than in the control rats; 0.5 mg/kg noradrenaline injections induced a clear RQ decrease in the former and did not influence the latters' RQ. Cold exposure was followed by a RQ decrease in both. Ganglion blocking agent administration decreased the RQ in the adapted animals and prevented it from falling in the control those. Noradrenaline is supposed to be the main but not the only factor activating lipolysis in the cold adapted animals. |
258 | Response to exogenous gonadotropins in the unresponsive ovary syndrome. | |
259 | A comparative study of metal and plastic (Karman) cannulae for first trimester abortion by suction curettage. | |
260 | Acute bacterial myositis following septic abortion. An unusual complication. | |
261 | The binding of substrates and inhibitors to dihydrofolate reductase. | |
262 | Euglena gracilis deoxyribonucleic acid polymerases: subcellular locations and variations during the cell cycle. | |
263 | Monomer complexes of polyadenylic acid. | |
264 | 5-Carbamoylmethyluridine: a new minor nucleoside of transfer ribonucleic acid. | |
265 | The protective effects of cephaloridine on rat kidney lysosomes in vitro. | |
266 | [In vitro studies on human ovarian contractility (author's transl)]. | |
267 | [Studies on the energy for sperm motility (author's transl)]. | |
268 | Properties of urophysial proteins (urophysins) from the white sucker, Catostomus commersoni. | |
269 | Glutamine synthetase in newborn mice homozygous for lethal albino alleles. | |
270 | Chromosomal basis of the merozygosity in a partially deploid mutant of Pneumococcus. | A sulfonamide-resistant mutant of pneumococcus, sulr-c, displays a genetic instability, regularly segregating to wild type. DNA extracts of derivatives of the strain possess transforming activities for both the mutant and wild-type alleles, establishing that the strain is a partial diploid. The linkage of sulr-c to strr-61, a stable chromosomal marker, was established, thus defining a chromosomal locus for sulr-c. DNA isolated from sulr-c cells transforms two mutant recipient strains at the same low efficiency as it does a wild-type recipient, although the mutant property of these strains makes them capable of integrating classical "low-efficiency" donor markers equally as efficiently as "high efficiency" markers. Hence sulr-c must have a different basis for its low efficiency than do classical low efficiency point mutations. We suggest that the DNA in the region of the sulr-c mutation has a structural abnormality which leads both to its frequent segregation during growth and its difficulty in efficiently mediating genetic transformation. |
271 | Recombination as a requirement for segregation of a partially diploid mutant of Pneumococcus. | Conditions are described in which the pneumococcal mutant strain sulr-c, resistant to the drug sulfanilamide, gives rise to sensitive segregants resistant to nitrobenzoic acid at a frequency constant with time. This segregant frequency is markedly enhanced upon exposure of the cells to doses of ultraviolet light or mitomycin C that permit survival of 50% to 90% of the cells. Treatment with acridine orange diminishes the segregant frequency. From the known influences of these three agents on genetic recombination, we propose that a recombination event is necessary in the generation of segregants.--During a period of incubation following treatment with ultraviolet light or mitomycin C, cell division resumes and the original segregant frequency is restored. Thus potential segregants are either unable to replicate in the absence of selection, or they are under-represented among the cells dividing soon after treatment.--If the sulr-c mutation is introduced into a mutant pneumococcal strain lacking an ATP-dependent exonuclease activity and deficient in recombination with transforming DNA, segregant frequencies are unaffected. This fact may indicate limits upon the type of recombination event responsible for segregation. |
272 | [Extrabronchial effects of Bronchodilat in patients with asthma and chronic asthmatic bronchitis]. | |
273 | Involvement of the small intestine in systemic mast cell disease. | A patient is reported with mast cell infiltration of the small intestine in the absence of the skin involvement characteristic of mast cell disease. She also had subtotal villous atrophy responsive to a gluten-free diet. Criteria for diagnosing mast cell disease of the small intestine are proposed. The literature of small intestinal mast cell disease is reviewed and the relationship to coeliac disease is discussed. |
274 | Gastric pH and microflora of normal and diarrhoeic infants. | The microflora and pH of gastric contents were determined in breast-fed and in bottle-fed normal infants, in well nourished infants with acute diarrhoea and in infants with chronic diarrhoea and protein-calorie malnutrition. The last group of infants was reevaluated after recovery from diarrhoea and protein-calorie malnutrition. A bactericidal pH effect below 2-5 was observed. Bottle-fed controls had low pH values and low bacterial concentrations, whereas infants with chronic diarrhoea and protein-calorie malnutrition had high pH values and bacterial overgrowth, essentially of Gram-negative bacilli. After recovery, the only remaining alteration was the frequent isolation of yeast-like fungi in low concentrations. Infants with acute diarrhoea, except for the isolation more frequently of yeast-like fungi, presented no alterations; this seems to indicate that pH alterations and Gram-negative bacilli overgrowth occurred during the evolution of the disease to a chronic state. Breast-fed normal infants had hydrogen-ion concentrations similar to those of the chronic diarrhoea group, but without Gram-negative bacilli overgrowth, suggesting that other factors, besides pH, regulate bacterial growth in the gastric contents of these groups of infants. |
275 | [Allogenic bone marrow transplantation in men]. | |
276 | [Bone marrow transplantation in patients with aplastic anemia]. | |
277 | [Analysis of clinical phenomena and changes in physico-chemical properties of the blood in mentally ill children]. | |
278 | [Biphasic (ulcer-forming and ulcer-preventing) effect of adrenaline in rats]. | Adrenaline-induced gastric ulceration was studied in rats. Adrenaline in high doses caused gastric ulcer, which was completely blocked by pretreatment with alpha-blockers (phenoxybenzamine, dibenamine), but not by pretreatment with propranolol or atropine, nor by vagotomy, hypophysectomy or adrenalectomy. After successive administration of adrenaline, once daily for 7 days, however, no gastric ulcer was observed. Recovery from the ulcerogenic action of adrenaline was seen after 4 weeks withdrawal. Pretreatment with a small dose of adrenaline inhibited the ulcerogenic action of a high dose of adrenaline. Pretreatment with reserpine, pyrogallol or iproniazid inhibited the action of adrenaline. It is concluded that adrenaline has a biphasic effect on gastric ulceration, the ulcerogenic action is due to its alpha-action and antiulcerogenic effect is due to development of tachyphylaxis. |
279 | [Comparison of drug effects on the isolated rat colon and duodenum]. | Adrenaline and isoproterenol elicited nearly maximal relaxation of the colon even in small doses, whereas increase in the doses caused greater relaxation in the duodenum. In the colon, these drugs prevented, to a great extent the contraction induced by acetylcholine (ACh) and serotonin but in the duodenum were totally ineffective. Dibenamine and propranolol reduced adrenaline- and isoproterenol-induced relaxation in the duodenum, though propranolol decreased the relaxation caused by isoproterenol. Atropine prevented ACh-induced contraction in both the colon and duodenum in the same way. After 2-bromolysergic acid diethylamide, duodenal contraction caused by ACh or serotonin decreased by over 70%; however, the contraction of the colon was not significantly inhibited. Methysergide had similar effects, but to a lesser degree. In calcium-free bathing fluid without addition of Na2EDTA, ACh and prostaglandin E1 elicited contraction in the colon, but not in the duodenum. |
280 | [Monoamine oxidase (XXXVI). Characteristics of benzylamine oxidase in the dog serum]. | Enzymic properties of monoamine oxidase (MAO) in dog serum were studied and the following results were obtained. Some of enzymic properties of MAO in dog serum differed from that of mitochondrial MAO. When dog serum was fractionated by ammonium sulfate, proteins were concentrated in two fractions, such as 25 approximately 33% and 67 approximately 80% of saturated ammonium sulfate fraction, while MAO activity was concentrated in 40 approximately 50% of saturated ammonium sulfate fraction. The reaction rate of MAO in dog serum was found to be proportional to enzyme concentration. The optimum pH of MAO in dog serum was 7.0 which differed from that of MAO in rabbit serum (pH 8.0). Tris-HCl buffer strongly inhibited MAO activity in dog serum. When benzylamine was used as substrate, the highest activity was obtained compared with the other substrate used. The activities with butylamine, amylamine, beta-phenylethylamine and tyramine showed about 30% while tryptamine and serotonin showed 3 approximately 10% compared to that with benzymlamine as substrate. The value of pI50 of catron was about 3 X 10(-6) M and that of harmaline was about 3 X 10(-5) M, but pargyline did not inhibit MAO activity in dog serum at the concentration of 1 X 10(-4) M. |
281 | [Combined use of bucolome and pyrazolone derivatives (1). Pharmacological activities and blood concentration]. | A combination of two or more drugs may exert a drug-drug interaction, in which case the effect can be potentiated or antagonized. Such synergistic effects are well known in the case of pyrabital (barbital + aminopyrine) or irgapyrine (phenylbutazone + aminopyrine). Bucolome (BCP), a non-steroidal anti-inflammatory agent, has the chemical structure of a barbiturate and also resembles the formula of pheylbutazone. Thus the influence of BCP combination on the pharmacological activities of various pyrazolone derivatives was examined. BCP potentiated the analgesic and antipyretic effects of 4-aminoantipyrine (4A), methylaminoantipyrine (MA), aminopyrine (AM) and isopropylaminoantipyrine (IPA), which were substituted by the alkylamino group at 4-position of the pyrazolone ring. This potentiation occurred when the dose of BCP exceeded that of the pyrazolones, and was especially marked when combination ratio of BCP exceeded that of the pyrazolones, and was especially marked when combination ratio of BCP and pyrazolone was 2:1 mola. The analgesic effects of antipyrine (AN), isopropylantipyrine (IP) and aminopropylone (AP), which were substituted by alkyl group or aminoacylamino group at 4-position, were not potentiated by BCP in any combination ratio. Most pyrazolones showed additive acute toxicity in their combination with BCP, but acute toxicities of 4A and AM, which were potentiated in analgesic effects, were decreased and antagonized when combined with BCP. The plasma concentration of AM was increased and prolonged by BCP, while that of IP remained much the same. These results suggest that the pharmacological activities are associated with certain molecular interactions between BCP and pyrazolones, which are substituted by the alkylamino group at 4-position of the pyrazolone ring. |
282 | [Combined use of bucolome and pyrazolone derivatives (II). Complex formation due to interaction between bucolome and pyrazolones]. | We have already reported that bucolome (BCP), a non-steroidal anti-inflammatory agent, potentiates significantly the analgesic and antipyretic effects of pyrazolones which are substituted by alkylamino group at 4-position of the pyrazolone ring. Physical and quantum chemistry were applied to the mechanism of this synergistic action. The solubility of BCP was markedly increased in proportion to elevation of aminopyrine (AM) concentration, but not by a combination with isopropylantipyrine (IP). The binding of BCP to bovine serum albumin was slightly inhibited by AM, but not by IP. The mixture of AM and BCP in aqueous media generated optical absorption in the ultraviolet differential spectrum, due to the charge transfer interaction. The results of the infrared or NMR spectrum demonstrated the formation of a hydrogen binding in non-aqueous media between BCP and AM. From the calculation of the charge on an atom, the energy of the highest occupied molecular orbital and the frontier electron density, BCP is considered to be a good electron acceptor. The beta-units of Mho of pyrazolones were found to correlate with the potentiation coefficient of analgesic activity in combination drugs. These results suggest that the complex formation between BCP and pyrazolones is an important factor for the synergism of action and is due to the charge transfer interaction and the hydrogen binding of both molecules. |
283 | Fructose 1,6-bisphosphate aldolase activity of Rhizobium species. | FDP aldolase was found to be present in the cell-free extracts of Rhizobium leguminosarum, Rhizobium phaseoli, Rhizobium trifolii, Rhizobium meliloti, Rhizobium lupini, Rhizobium japonicum and Rhizobium species from Arachis hypogaea and Sesbania cannabina. The enzyme in 3 representative species has optimal activity at pH 8.4 in 0.2M veronal buffer. The enzyme activity was completely lost by treatment at 60 degrees C for 15 min. The Km values were in the range from 2.38 to 4.55 X 10(-6)M FDP. Metal chelating agents inhibited enzyme activity, but monovalent or bivalent metal ions failed to stimulate the activity. Bivalent metal ions in general were rather inhibitory. |
284 | Prevention of cell agglutination and competence in a genetically transformable strain of Pneumococcus by D-glucosamine and D-galactosamine. | In the presence of amino sugars D-glucosamine and D-galactosamine no spontaneous competence could be observed in the highly transformable R6bd strain of Pneumococcus or it was decreased by several orders of magnitude. The highest inhibition of competence was detected when the amino sugar at a concentration 5 mg/ml of the medium was added not only to the transformation but also to the pretransformation medium. After a 150 min growth in the transformation medium in the presence of the amino sugar a 3--4-fold greater number of cells (as a viable count) could be detected as compared with the control without the amino sugar. It was found microscopically that the amino sugar prevents natural agglutination, which normally occurs in the competent culture. The role of specific amino sugar determinants for binding of the competence factor on the cell surface and the resulting inhibitory effect of these sugars on the development of competence are discussed. |
285 | Effect of some aldoses on growth of Saccharomyces cerevisiae inhibited with molybdenum. | The inhibitory effect of molybdenum ions on growth of yeasts at pH 5.5 was found to be decreased by aldoses in the following order: D-talose greater than L-mannose greater than L-ribose greater than D-lyxose greater than L-galactose greater than L-arabinose greater than L-glucose greater than L-xylose. Increased concentrations of molybdenum brought about morphological changes of yeast cells. Cells grown under these conditions were smaller, had thicker walls and formed clusters. |
286 | Transport properties of membrane vesicles from Acholeplasma laidlawii. II. Kinetic characteristics and specificity of glucose transport system. | The glucose transport system of membrane vesicles isolated from Acholeplasma laidlawii is saturable, with a Km of 21.2 mum and V of 0.68 nmol min-1 (mg protein)-1. The process is pH-dependent and a break occurs in the Arrhenius plot at 15 degrees C. Exogenous substrates did not stimulate glucose transport probably due to their inability to penetrate into membrane vesicles. 3-O-Methylglucose and 6-deoxyglucose competitively inhibited glucose transport. Maltose inhibited transport of glucose noncompetitively. These sugars also elicited glucose efflux from preloaded membrane vesicles. |
287 | Transport of 4-deoxy- and 6-deoxy-D-glucose in baker's yeast. | Tritium-labelled 4-deoxy-D-glucose (4-dglc) and 6-deoxy-D-glucose (6-dgcl) were prepared by catalytic hydrogenolysis of the corresponding deoxyiodo derivatives with gaseous tritium. The two sugars are transported into Saccharomyces cerevisiae by both the constitutive glucose and the inducible galactose carrier. Uranyl ions are powerful inhibitors. The pH optimum in uninduced cells lies at 5.5 for both sugars, the apparent activation energies (between 15 and 35 degrees C) are 25.1 kJ/mol and 16.5 kJ/mol, respectively. The steady-state intracellular concentration of both sugars is less than the extracellular one (no uphill transport). Neither of them is a substrate of yeast hexokinase. 4-Deoxy-D-glucose undergoes a dinitrophenol-sensitive conversion to an unknown metabolite which is not phosphorylated and may represent one of its oxidation products. |
288 | Gluconic acid production by Penicillium puberulum. | Twenty-five Penicillium species isolated from Egyptian soil were examined for their ability to produce gluconic acid in surface culture. Of the eight species capable of producing gluconic acid, Penicillium puberulum gave the maximum yield (91% gluconic acid from glucose after 7 days of fermentation with 3% CaCO3). Peptone was the best nitrogen source for acid fermentation and glucose was superior to sucrose. Addition of low concentrations of KH2PO4 and MgSO4 - 7 H2O stimulated acid production. An initial pH of 6.1 was most favourable for acid accumulation and addition of CaCO3 was necessary for maximum acid production. |
289 | A simple method of isolation and purification of cultures of wood-rotting fungi. | A simple method of isolation and purification of cultures of higher fungi, mainly wood-rotting fungi, without special requirements for the presence of nitrogencontaining nutrients is described. Parts of fruiting bodies, spores or infected wood is inoculated on Petri dishes with an agar medium of the following composition: 1.0 g KH2PO4, 0.2 g MgSO4 - 7 H2O, 0.1 g caSO4, 0.01 g Fe2(SO4)3, 10.0 g glucose, tap water to 1 litre; 20.0 g agar. This medium does not suit most of the contaminants but fungal hyphae overgrow the whole surface of the dish so that a purified culture can be obtained from parts distant from the inoculation site. |
290 | The effect of CTAB, a cationic surfactant, on the absorption rate of [14C]tripalmitate from a test meal in the rat. | |
291 | [Language of the other]. | |
292 | [Studies on low volume priming heart lung bypass (author's transl)]. | This report concerns the feasibility of low volume priming extracorporeal circulation. Through this study, the bubble oxygenator with Zuhdi's heat exchange was used. Moderate hypothermia with surface cooling and hemodilution perfusion with 5 per cent D/W was evaluated in 32 mongrel dogs and 16 clinical open heart cases. The results obtained here were as follow: 1) Body temperature reduction by surface cooling before bypass provided more even cooling than did core cooling by low flow partial bypass alone. 2) In regard to cardiac loading on returning the whole perfusate of the circuit to patient, approximately 20 ml/kg of 5 per cent D/W was feasible as a priming solution. 3) To reduce the blood visicosity, hemodilution technique with 5 per cent D/W was superior, and hemodilution effect during postoperative periods was temporaly. 4) The excess lactate volume postulated by Huckabee was a available index to evaluate metabolic acidosis during the extracorporeal circulation. 5) With aid of surface cooling, the acid-base balance during perfusion was kept to lesser extent than that of core cooling only. 6) This study indicated that the low priming perfusion in conjunction with surface cooling hypothermia was a reliable technique for the open heart operation and may be applied in more prolonged perfusion. |
293 | [Studies on extracorporeal circulation with large volume hemodilution using lactate ringer's solution and low molecular weight dextran: alterations of acid-base balance associated with intentional hemodilution (author's transl)]. | Twenty mongrel dogs, weighing between 7.5 and 13.0 kg were used to investigate the percentage limits permissible for hemodilution using a double-helical reservoir heart-lung machine which has a 1,100 ml of priming volume. In both 40 and 50 per cent groups of intentional hemodilution by 30 minute extracorporeal circulation, remarkable anemia was inevitable and recovery was extremely slow, especially in the 50 per cent dilution group. In both 40 and 50 per cent groups of intentional hemodilutions by 30 minute extracorporeal circulation, metabolic acidosis was observed. In 50 per cent group of intentional hemodilution, no improvement of metabolic acidosis was observed even after perfusion. When sodium bicarbonate was administered to 40 per cent hemodilution group, minimum alterations of acid-base balance and of serum electrolytes were observed during and after extracorporeal perfusion. When sodium bicarbonate was administered to 50 per cent hemodilution group, metabolic acidosis was more evident than in 40 per cent hemodilution group accompanied with an increase in serum sodium concentration and a decrease in serum chloride concentration. These data qualify the use of 40 per cent intentional hemodilution using Lactate Ringer's solution or low molecular weight dextran for 30 minute extracorporeal circulation when sodium bicarbonate is administered in adequate amounts. |
294 | [Malignant rheumatoid arthritis]. | |
295 | Purification and characterization of phosphodiesterase from Crotalus venom. | A procedure for the purification of phosphodiesterase from Crotalus venom on DEAE-cellulose at alkaline pH is described. The enzyme gives a single band in polyacrylamide gels and is free of contaminating nucleolytic enzymes. The molecular weight is about 115000. Concentration in an Amicon ultrafiltrator gave a highly concentrated active enzyme. Phosphodiesterase is relatively stable and can be stored at 4 degrees C in the presence of Mg2 and serum albumin for years. For the detection of contaminating endonuclease, an assay was used in which tRNA was the substrate and possible internal breaks were detected in polyacrylamide gel after denaturation. With bis(p-nitrophenyl) phosphate as substrate, 15mM Mg2 was necessary for optimal activity. The reaction remained linear for at least 15 min at 22 degrees C. At 45 degrees C, the liberation of p-nitrophenol was highest within 25 min of incubation. At 75 degrees C, inactivation of the enzyme occurred after 4 min. |
296 | Limited hydrolysis of tRNA by phosphodiesterase. | Digestion of tRNA by electrophoretically pure phosphodiesterase is limited to a short sequence of nucleotides at the 3'-terminus. On the average, four percent of all nucleotides can be released from tRNA. The optimum Mg2 concentration is 10mM and the optimum pH 9.2. The mode of action is a random attack by the enzyme on the substrate. The terminal AMP is completely removed at 15 degrees C after short incubation; about 400 mol of AMP were removed per min by 1 mol of enzyme. The following CMP residues are released much more slowly; at 15 degrees C incompletely, and at 37 degrees C more or less completely in 1 h. In about 50% of the tRNA molecules, the fourth nucleotide could be removed in very long incubations or with very high enzyme concentrations. |
297 | Ecdysone Oxidase, an enzyme from the blowfly Calliphora erythrocephala (Meigen). | In the blowfly, the formation of 3-dehydroecdysone from the insect molting hormone ecdysone is catalyzed by an enzyme which carries hydrogen from ecdysone and ecdysterone to oxygen. The enzyme is therefore called "ecdysone oxidase". Two methods are described for the detection of ecdysone oxidase activity, one using a radiolabelled substrate which is separated from the product by thin-layer chromatography after the reaction, and the other using dichloroindophenol, which is discoloured by the redox reaction. The ecdysone oxidase is purified by a factor of 2200 from prepupae of Calliphora erythrocephala using salt precipitation and ion exchange chromatography. The ecdysone oxidase has a Km value for ecdysone of 42muM. The pH optimum is 6.5. The temperature optimum lies at 45 degrees C. The ecdysone oxidase has a molecular weight of 240000. |
298 | Using a hospital for desensitization of an outpatient's illness-related fears. | An outpatient with phobias related to enclosed places, hospitals, doctors, and cancer was treated by systematic desensitization; the facilities of a general hospital were used for part of the process. Steps in treatment included securing a complete psychiatric and social history, teaching the patient relaxation therapy techniques, and establishing a hierarchy of anxiety-provoking stimuli specifically related to the patient's fears. After desensitization the patient was able to enter the hospital for tests for a physical ailment and showed a general decrease in her fears. |
299 | Analog computer for base excess and HCO3-from pH and PCO2 electrodes. | |
300 | Alcohol-related problems in a general hospital emergency room. |