Comparative effects of (--)-hydroxycitrate and (+)-allo-hydroxycitrate on acetyl CoA carboxylase and fatty acid and cholesterol synthesis in vivo. (--)-Hydroxycitrate and (+)-allo-hydroxycitrate were investigated for their effects on lipid synthesis in vivo under conditions of either high carbohydrate feeding or 24 hr fasting. Changes in rates of lipid synthesis resulting from the oral administration of these compounds were monitored with the use of radiolabeled H2O, alanine, and acetate. In the fed rat, (--)-hydroxycitrate significantly reduced the incorporation of H2O and alanine into fatty acids and cholesterol. An increased incorporation of labeled H2O into fatty acids but no change in cholesterol synthesis in the fasted rat suggested that (--)-hydroxycitrate may be an activator of acetyl CoA carboxylase. With (--)-hydroxycitrate administration, acetate incorporation into fatty acids and cholesterol was subject to pool dilution effects under fed or fasted states. (+)-allo-Hydroxycitrate was ineffective in modulating the rates of fatty acid synthesis under either nutritional condition. Both (--)-hydroxycitrate and (+)-allo-hydroxycitrate were shown to be in vitro activators of acetyl CoA carboxylase, the former being a much stronger activator than the latter. Thus, stereospecificity of the hydroxycitrate isomers was demonstrated in both the inhibition of lipid synthesis (previously shown to occur at adenosine triphosphate citrate lyase) and the stimulation of fatty acid synthesis (possibly occurring at acetyl CoA carboxylase).


Fetal fuels. I. Utilization of ketones by isolated tissues at various stages of maturation and maternal nutrition during late gestation. The availability and utilization of B-hydroxybutyrate as an alternate oxidative fuel during fasting hypoglycemia has been examined in the rat conceptus at 18 and 20 days gestation. A 48-hr maternal fast between days 16 and 18 or 18 and 20 resulted in a 50% fall in fetal glucose levels and a marked rise in B-hydroxybutyrate, i.e., 30-fold at 18 and 60-fold at 20 days. Tissue concentrations of B-hydroxybutyrate or acetoacetate did not exceed extracellular levels. Placenta, fetal brain, carcass, and liver all oxidized 14C-labeled B-hydroxybutyrate to 14CO2 when incubated in vitro in the presence of B-hydroxybutyrate. Highest rates of oxidation were apparent in the placenta, followed by brain, liver, and carcass. The D isomer of B-hydroxybutyrate appeared to be oxidized preferentially by all tissues studied. Despite levels of 3-ketoacid CoA transferase and acetoacetyl CoA thiolase lower at 18 than at 20 days, rates of oxidation in individual tissues incubated under identical concentrations of substrate were similar at both times. In liver and brain, increasing rates of 14CO2 generation proportionate to graded concentrations of B-hydroxybutyrate in vitro indicated that such rates were probably determined by substrate availability. B-hydroxybutyrate oxidation in extrahepatic fetal tissues was unaffected by maternal fasting. By contrast, fetal liver derived from fasted mothers generated significantly less 14CO2 from B-hydroxybutyrate than livers from fed mothers. It has been suggested that capabilities for ketone utilization are widespread in tissues of the conceptus, and that such utilization may fulfill in part the oxidative demands for continued anabolic growth during fasting hypoglycemia in the mother.


Studies on the toxin of Aspergillus fumigatus. VII. Purification and some properities of hemolytic toxin (asp-hemolysin) from culture filtrates and mycelia. A hemolytic toxin has been obtained from mycelia and culture filtrates of Aspergillus fumigatus by the procedures that included precipitation with ammonium sulfate, chromatography of DEAE-Sephadex, affinity chromatography on Concanavalin A-Sepharose and gell filtration on Sephadex G-50, G-100 AND G-150. The purified homolytic toxin was homogeneous on immunological and disk electrophoretic analysis, and the toxin from culture filtrates was identical with that from mycelia by the immunodiffusion technique. The hemolytic toxin was obtained for the first time from fungi and designated as Asp-hemolysin. The molecular weight of Asp-hemolysin was estimated to be appoximately 30,000 by the gel-filtration technique and its isoelectric point was found to be around pH 4.0. This Asp-hemolysin contained large amounts of protein and very small amounts of carbohydrate. The UV absorption spectrum of Asp-hemolysin showed a maximum absorption at 280 nm and minimum absorption at 251 nm. The extinction coefficient at 280 nm and minimum absorption at 251 nm. The extinction coefficient at 280 nm, E 1% 1CM, was 12.4 and the ratio of absorbance at 280 nm to that at 260 nm was 2.3. The optimum pH for the hemolytic activity of the toxin toward chicken erythrocytes was 5.0 at room temperature and it was active in the pH range of 3.5 to 10.5. The optimum temperature was 21 C and about 50% of the activity was lost by incubation at 50 C for 5 min or 45 C for 23 min. The hemolytic activity was remarkably inhibited by Hg2+, Cu2+, Fe2+, Ag1+, iodine and p-CMB, but enhanced slightly by Zn2+ and Co2+.


Resistance mechanism of chloramphenicol in Streptococcus haemolyticus, Streptococcus pneumoniae and Streptococcus faecalis. The chloramphenicol resistance of Streptococcus haemolyticus, Streptococcus pneumoniae and Streptococcus faecalis isolated from clinical materials was proved to be due to an inactivating enzyme produced by these bacteria. The inactivated products of chloramphenicol were identified as 1-acetoxy, 3-acetoxy and 1,3-diacetoxy derivatives by thin-layer chromatography and infrared spectroscopy. The responsible enzyme was thus confirmed to be chloramphenicol acetyltransferase. The enzyme was inducible. It was partially purified by ammonium sulfate precipitation, DEAE-cellulose chromatography and gel filtration on Sephadex G-150. The enzymes obtained from S. haemolyticus, S. pneumoniae and S. faecalis have been compared with the conclusion that they are identical with respect to molecular weight (approximately 75,000-80,000), optimum pH and heat stability.


[Physiologo-biochemical properties of a chemostatic culture of Bacillus megaterium at different pH values]. Properties of the chemostat culture of Bacillus megaterium were studied during its growth in the state of stress caused by unfavourable acid and alkaline values of pH. The effect of pH is not specific since changes occur in both energy exchange and constructive metabolism. The common action of hydrogen and hydroxyl ions is a decrease in the economic coefficient as greater amounts of the energy substrate are being used, the repression of oxidative enzymes, a decrease in the pool of ATP, and an increase in the respiration quotient. Protein synthesis is inhibited and synthesis of nitrogenless reserve substances is stimulated. Acid and alkaline conditions have also a specific action in the cells of Bac. megaterium. In the alkaline medium, metabolites are liberated into the medium, the cells are enriched with carbohydrates, and acetate is accumulated in the medium. In the acid medium, the cells are enriched with acid insoluble polyphosphates. Idle consumption of the energy substrate takes place.


Cimetidine in the treatment of duodenal ulcer. In a double-blind trial performed in two centres, 67 outpatients with endoscopically confirmed duodenal (55) or pyloric canal (12) ulcers received cimetidine (34 patients) or placebo (33 patients) for six weeks. At 6 weeks complete healing of ulcers was significantly increased in patients receiving cimetidine (82%) compared with those receiving placebo (39%) (chi2=11-27; P less than 0-0008). Patients receiving cimetidine had significantly less daytime pain and required less antacid than those receiving placebo. Gastric acid secretion measured one week after cessation of treatment demonstrated that there was no rebound hypersecretion of acid in patients who had received cimetidine. The pretrial basal acid output of those patients whose ulcers failed to heal during cimetidine therapy was significantly greater than that of those whose ulcers healed during treatment with the drug (P less than 0-001). No side effects were encountered.


[Methanol oxidation by the NAD-specific dehydrogenase of methane-assimilating yeasts]. The activity of NAD-specific dehydrogenase (NAD-DH) capable of methanol oxidation was found in cell-free extracts of methanol assimilating yeast cultures Pichia pinus and Candida boidinii. The optimum pH of the incubation mixture for the enzyme is 7.8--7.9; the value of Km of the enzyme for methanol is 1.4-10(-4) M in P. pinus and 1.04-10(-3) M in C. boidinii. NAD-DH is absent from the cells cultivated on glucose, and is induced with growth on a medium containing methanol.


[Properties of the hexulose phosphate synthase of methylotrophic yeasts and bacteria]. Properties of hexulose phosphate synthase (HPS) were studied in extracts of the methanol assimilating yeast Candida methylica and the bacterium Arthrobacter globiformis B-175 assimilating methylated amines. HPS is an inducible enzyme which is localized in the soluble fraction of the cells. The effect of the pH of the reaction mixture, temperature, metal ions, and the concentration of substrates on the activity of HPS was studied. Properties of the enzyme were different in the yeast and the bacterium. The activity of HPS was strongly stimulated by ATP in C. methylica and was not affected in A. globiformis.


A study of cancer of the breast with special reference to its causation and prevention. Breast feeding, lactational histories, parity, age at marriage, and socio-economic status were compared in 24 patients with carcinoma of breast, 24 healthy controls, and 48 patients suffering from other diseases. They were matched for age, social class and work or trade of the husbands. Breast cancer patients married later, had shorter lactational histories and had fewer children as compared with controls. Studies in six healthy mothers showed that milk became more alkaline on stasis in the breast. This study confirms the view that breast feeding protects against breast cancer. It suggests that one carcinogenic factor may be an alkaline milieu produced by the statis of milk in the breasts. An alkaline milieu surrounding epithelial surfaces produces cell proliferation and a marked increase in mitotic activity which may eventually lead to metaplasia and neoplasia.


[Cogans's syndrome in childhood (author's transl)]. A case--report is given of a patient with Cogan's syndrome in childhood. This syndrome consists of non-syphilitic interstitial keratitis and vestibuloauditory symptoms. Visual loss is rare but hearing loss is rapidly progressive. A relation to autoimmune diseases especially to panarteriitis nodosa has been suggested by a number of authors.


Enzyme replacement therapy of exocrine pancreatic insufficiency in man. Relations between in vitro enzyme activities and in vivo potency in commercial pancreatic extracts. I assayed 16 commercially available pancreatic extracts (representing capsules, tablets and enteric-coated tablets) for enzyme activities and the relation between the in vitro activities and in vivo potency evaluated in man. Lipase activity ranged from 10 to 3600 units per unit, with 11 preparations containing less than 600 units per unit. The preparations with the highest lipase activities were llozyme, 3600, Kuzyme HP, 2330, Festal, 2073, Cotazym, 2014, and Viokase, 1636 units. Lipase activity in vitro correlated with potency in vivo for tablets and capsules, with tablets and capsules being effective in reducing steatorrhea by 56.1 +/- 9 per cent and 48.6 +/- 10 per cent (mean +/- S.E.M.) respectively, P less than 0.001. Enteric-coated tablets were less effective (20 +/- 13 per cent reduction, P greater than 0.02). The longer the gastric pH remained greater than or equal to 4 (r = 0.915, P less than 0.01) and the higher the average duodenal pH (r = 0.966, P less than 0.01), the more marked the reduction in steatorrhea.


A possible histochemical mechanism of dihydrofolate reductase reaction. The authors propose a hypothesis concerning the mechanism of dihydrofolate reductase reaction, suggesting a combined action of transhydrogenases and diaphorase particularly for this enzyme activity, and generally for the reductases.


Fate of orally ingested enzymes in pancreatic insufficiency. Comparison of two dosage schedules. To assess the fate and efficacy of orally ingested enzymes in pancreatic insufficiency, we administered pancreatin to six patients by two schedules--eight tablets with a standard meal or two tablets hourly--and in six normal controls, quantified duodenal enzyme activity and related inactiviation of ingested enzymes to gastric and duodenal pH; in the six patients we measured malabsorption by fecal balance studies. Postprandially, gastric pH was similar in health and pancreatic insufficiency, and below 4 after 40 minutes. Duodenal pH in pancreatic insufficiency declined to approximately 4 beyond 100 minutes--lower than in health (P less than 0.05). Approximately 22 per cent and 8 per cent of trypsin and lipase activity ingested with either schedule was delivered to the ligament of Treitz. Prandial was as effective as hourly administration in decreasing steatorrhea and perhaps more effective in abolishing azotorrhea, and since it is also more convenient, we recommend it.


[Determination of riboflavin in foods].

[Determination of riboflavin in foods]. The author examined the conditions under which the lumiflavin method may be used for the determination of riboflavin. Neither the presence of various cations and anions, nor the presence of cellulose, starch and protein exerted any effect on the oxidation with potassium permanganate. The riboflavin losses increased when potassium permanganate was used at a concentration of more than 2%. The losses were considerably lower it the purification of the extracts by means of potassium permanganate was performed after photolysis. The most favourable results were obtained when the extracts were shaken with chloroform prior to photolysis to eliminate interfering substances. These findings were corroborated by comparative analyses on 3 standard samples.


Comparative neutron small-angle scattering study of small spherical RNA viruses. Small-angle neutron scattering from solutions of small RNA viruses has been used to study protein-nucleic acid organisation. In the five viruses investigated the RNA is confined to a sphere of about 100 A radius, with a central hole (with one possible exception). The interpenetration of RNA and protein varies with viruses and seems to be related to the natrue of the forces stabilising the virus.


Effects of neuroleptics on release of 3H-dopamine from slices of rat corpus striatum. The characteristics of 3H-DA release from striatal slices by electrical stimulation were analyzed and the effects of a number of neuroleptics thereon were examined under different experimental conditions. The butyrophenones, haloperidol and spiroperidol, already at low concentrations (0.1 - 1 micronM) increased basal tritium efflux in a dose-dependent manner. The phenothiazines, chlorpromazine and fluphenazine, were much less effective in this respect. The butyrophenones strongly inhibited the electrically stimulated overflow of both 3H-DA and 14C-GABA, while the phenothiazines again had little effect. The action of 1 micronM haloperidol on 3H-DA release could be blocked by 10 micronM cocaine, but not with 1 micronM apomorphine. Apomorphine itself had no significant effect on 3H-DA release. Our data do not support the suggestion that presynaptic DA receptors on dopaminergic nerve terminals may modulate the release of newly taken-up 3H-DA. Some neuroleptics, particularly the butyrophenones may have presynaptic effects not related to interaction with DA receptors. It is suggested that different mechanisms may be involved in the local presynaptic receptor-mediated feedback regulation of transmitter release in noradrenergic and dopaminergic systems in the CNS.


[Quantitative relationship between neurons of a different mediator nature in the motor nuclei of the cat spinal cord cervical thickening]. A histochemical analysis of the neuronal composition of the motor nuclei was performed on the cat cervical spinal cord. Motoneurons were distinguished by the location of AChE in the perinuclear space, on the membranes of the granular reticulum, on the axolemma, neurofilaments and neurotubuli, in the synaptosomes and the synaptic cleft; this evidences for the perinuclear synthesis of this enzyme and its transport within the axoplasm. Their amount reached 40-65% of the whole neuronal population. AChE identification together with autoradiographic tracing of glycine showed that large cholinergic motoneurons are accompanied by small glycine-accumulating neurons with short processes which form axo-somatic and axo-dendritic contacts with large neurons. The cholinergic motoneurons have polyreceptive properties, as can be concluded from the presence of AChE and glycine-containing terminals on their soma and processes, as well as some noradrenergic and serotoninergic and many unidentified terminals.


Salivary levels of anticonvulsants: a practical approach to drug monitoring. Phenobarbital, phenytoin, carbamazepine, primidone, and ethosuximide were measured in saliva and plasma obtained simultaneoulsy from 115 patients. A method to correct for the effect of salivary pH on phenobarbital concentration of saliva was developed. Salivary concentrations of these drugs were found to be equivalent to the plasma free drug and to correlate closely with the total plasma levels. Expressed as percent of total plasma drug, the salivary (S) and plasma free (P) concentrations were: phenytoin, S 11.1 +/- 2.0 percent  (mean +/- SD), P 10.1 +/- 2.4 percent (r = 0.97); carbamazepine, S 26.0 +/- 2.4 percent, P 25.9 +/- 3.4 percent (r = 0.97); phenobarbital, S 43.1 +/- 5.2 percent, P 40.8 +/- 7.9 percent (r = 0.91); primidone, S 75.4 +/- 24.9 percent, P 66.4 +/- 8.8 percent (r = 0.76). Ethosuximide was not bound by plasma proteins, and its plasma and salivary levels were equal.


[Guide to the automated calculation of acid-base equilibrium]. The sequence of calculations that can be entered in the memory of a desk computer for the automatic calculation of acid base balance parameters using data obtained with Astrup's tonometric method is described. A statistical comparison is also made between manually obtained results and those obtained with computer assistance. For clinical purposes the comparison is satisfactory.


Cataract and gamma-glutamyl cycle in myotonic dystrophy. Gamma-Glutamyl transpeptidase (gamma-GT) may be responsible for the rapid catabolism and low levels of lenticular glutathione often associated with cataract formation. Elevated levels of serum gamma-GT in patients with myotonic dystrophy suggest that since the defect could be present in all tissues it might be responsible for the cataracts frequently observed in this genetic disease.


Are infantile periarteritis nodosa with coronary artery involvement and fatal mucocutaneous lymph node syndrome the same? Comparison of 20 patients from North America with patients from Hawaii and Japan. We reviewed available clinical and pathologic autopsy material from 20 patients with infantile periarteritis nodosa with coronary artery involvement (IPN) from the continental United States, two Hawaiian patients with fatal mucocutaneous lymph node syndrome (MCLS; Kawasaki disease), and three patients with classical periarteritis nodosa (CPN). Comparison of the findings in patients with IPN and in patients with MCLS from Hawaii to material from patients with fatal MCLS from Japan showed no definite clinical reason to distinguish IPN from MCLS; neither gross nor microscopic features of the vascular lesions nor their pattern of distribution appears to warrant separation of IPN from fatal MCLS. CPN differs, both clinically and pathologically, from IPN/MCLS, and may well have a different etiology.


[Variation of plasma amino acids in severe hepatitis with encephalopathy 10 cases]. Plasma levels of different amino acids were observed in 10 patients with severe hepatitis, 9 viral in origin and 1 toxic, over the course of the disease. There would appear to be a close relationship between the onset of encephalopathy and the appearance of a particular pattern in plasma amino acid equilibrium, characterised by a significant fall in the molar ratio existing between ramified amino acids (valine, leucine, isoleucine) and aromatic amino acids (phenylalanine and tyrosine). The role of these disturbances in the physiopathology of the encephalopathy and their effects on the synthesis of normal neurotransmitters and the intracerebral accumulation of false neurotransmitters is discussed.


Analgesic action of alpha-adrenolytics in albino mice. The effect of alpha-adrenolytics: phenoxybenzamine, phentolamine, aceperone, dihydroegotamine, and yohimbine, was tested on reactivity to pain, and on the analgesic action of morphine and pethidine in albino mice. The compounds exert an analgesic effect by themselves, and potentiate the analgesic action of threshold doses of morphine and pethidine. The results seem to provide another proof that the cerbral noradrenaline neurons participate in central mechanisms of pain perception.


The different effects of sodium bicarbonate and aluminium hydroxide on the absorption of indomethacin in man. The influence of oral sodium bicarbonate and aluminium hydroxide on the absorption of indomethacin has been studied in normal volunteers. While sodium bicarbonate appeared to increase indomethacin absorption, aluminium hydroxide markedly reduced both the rate and extent of absorption. The buccal absorption of indomethacin over the pH range 5-9 was also studied in normal volunteers, and showed that the percentage absorption increased markedly as the pH was reduced. The clinical importance both of pH-partition and of adsorption are discussed in the context of antacid interactions. It is concluded that caution must be exercised when prescribing an antacid with other orally-administered drugs.


Factors which might modify analgesic effect of morphine in differentially housed rats. The analgesic effect of morphine was studied by tail compression method in grouped and chronically isolated Wistar male rats developing muricide behavior showed increased pain threshold whilst indifferent (non-killer) showed reduced responses to the analgesic action of morphine. "Natural" killer (housed in groups) showed, on the other hand, increased sensitivity to morphine. The role of factors such as isolation period, behavioral pattern and contact with the victim was discussed.


Kinetics of drug decomposition. Part 46. Photooxidation and photolysis of some perazine derivatives. The rate and type of the photochemical degradation of perazine derivatives in acidic aqueous solutions depends upon the nature of the substituent at C2 atom. Free perazine degrades by two parallel reactions, namely a fast reversible first-order photooxidation and a slow zero-order photolysis. An introduction of the substituent in the C2 position results frequently in the elimination of one of these reactions.


Kinetics of drug decomposition. Part 47. Effect of substituents on photochemical stability of perazine derivatives. A quantum yield phi of photooxidation of perazine derivatives estimated actinometrically and the pKa, values were used for the correlation with the substituent volumes. The Hammett type plots of phi= f(sigma) and phi= f(pKa10--pKa1) are discussed.


Nitrogen-15 nuclear magnetic resonance of aliphatic tripeptides. The 15N chemical shifts of eight aliphatic tripeptides have been measured at the natural-abundance level. For a given tripeptide, the resonances of the COOH-terminal and NH2-terminal amino acids can be identified by measurements at low or high pH. The shifts of the NH2-terminal amino acid nitrogens are essentially independent of the amino acids in the rest of the peptide. The shifts of the other nitrogens are characteristic of the amino acids themselves and of the immediately preceding amino acid toward the NH2 terminus. Non-terminal amide nitrogens have shifts of about 6 ppm upfield of COOH-terminal amide nitrogens at the isoelectric point of measurement. 15N chemical shifts appear to have considerable potential value for peptide sequencing.


Regulation of cholesterol synthesis in rat adrenal gland through coordinate control of 3-hydroxy-3-methylglutaryl coenzyme A synthase and reductase activities. The activities of cytosolic 3-hydroxy-3-methylglutaryl coenzyme A synthase [3-hydroxy-3-methylglutaryl-CoA acetoacetyl-CoA-lyase (CoA-acylating), EC 4.1.3.5] and microsomal 3-hydroxy-3-methylglutaryl coenzyme A reductase[mevalonate:NADP+ oxidoreductase (CoA-acylating), EC 1.1.1.34], two sequential enzymes in the cholesterol biosynthetic pathway, were shown to be regulated coordinately in the adrenal gland of the rat. When the plasma cholesterol level was lowered by administration of 4-aminopyrazolopyrimidine, a treatment known to enhance cholesterol synthesis in the adrenal, synthase activity in the gland rose by 14- to 29-fold and reductase activity rose by 50- to 100-fold. The subsequent intravenous infusion of low density lipoprotein restored the plasma cholesterol level and suppressed synthase and reductase activities in parallel. The activities of adrenal 3-hydroxy-3-methylglutaryl coenzyme A synthase and reductase were also shown to exhibit a coordinate pattern of diurnal variation with peaks in both enzymes achieved at the mid-point of the dark cycle. The activity of adrenal acetoacetyl coenzyme A thiolase (acetyl CoA acetyltransferase; acetyl-CoA:acetyl-CoA C-acetyltransferase, EC 2.3.1.9), the enzyme preceding the synthase in the cholesterol biosynthetic pathway, and the activity of adrenal mevalonate kinase (ATP:mevalonate 5-phosphotransferase, EC 2.7.1.36), the enzyme following the reductase, were not enhanced by cholesterol deprivation, and neither exhibited a pattern of diurnal variation. The coordinate control of 3-hydroxy-3-methylglutaryl CoA synthase and reductase in rat adrenal gland provides a model system to study the biochemical mechanism for the regulation of cholesterol synthesis in a tissue that uses cholesterol for the synthesis of steroid hormones.


Cell wall extension in Nitella as influenced by acids and ions. The giant internode cells of Nitella axillaris exhibit acid-induced growth similar to that found in higher plants. The threshold pH is 4.5, with a maximum at 3.5. The acid growth effect is transient, lasting no more than 32 min. Extensibility measurements of isolated cell walls showed a similar pattern of acid enhancement. Prolonged boiling in water (12 hr) only partially inhibited the acid-induced wall extensibility and actually increased the extensibility at pH 6. It was concluded that physical, rather than enzymatic, processes were responsible for acid-enhanced continuous extension ("creep") in Nitella walls. A complex cation-sensitive mechanism that affects extensibility was also characterized. Among the stimulatory (wall-softening) cations, divalents were generally more effective than monovalents, with magnesium being the most stimulatory. The inhibitory (wall-hardening) cations included divalents and trivalents, aluminum being the most inhibitory. Ionic effects on extensibility were even less sensitive to prolonged boiling in water than acid effects.


The product of a newly identified gene, gInF, is required for synthesis of glutamine synthetase in Salmonella. The product of a newly identified gene, glnF, which is distinct from the glutamine synthetase structural gene (glnA), is required for synthesis of glutamine synthetase [L-glutamate:ammonia ligase (ADP-forming), EC 6.3.1.2[ in Salmonella typhimurium and probably in Escherichia coli. Salmonella strains with ICR (2-chloro-6-methoxy-9-[3-(2-chloroethyl)aminopropylamino]acridine dihyodrochloride)-induced (frameshift) mutations in glnF are glutamine auxotrophs; they have less than 10% oof wild-type glutamine synthetase activity or antigen and are unable to derepress the synthesis of the enzyme. The mutant allele is recessive to the wild-type allele, indicating that the glnF gene encodes a diffusible product. Mutant glnF strains have normal activities of all proteins involved in covalent modification of glutamine synthetase: adenylyltransferase (EC 2.7.7.42), PII, uridylyltransferase, and uridylyl removing enzyme. In addition, they have glutamate synthase (EC 1.4.1.13) and glutamate dehydrogenase (EC 1.4.1.4) activities. Thus, glnF does not encode the structure of any of these proteins. The above evidence suggests that the product of the glnF gene is (or produces) a positive regulatory factor that is required for synthesis of glutamine synthetase; it indicates that auto-regulation cannot account for control of the synthesis of glutamine synthetase in Salmonella.


Synthesis of certain benzo- and pyridodiazepines likely to possess tranquilizing effect. The synthesis of certain 1.5-benzodiazepinediones, some of their oxygen-free analogues and a number of the 7-nitro derivatives is described. Condensation of 3.4-diaminopyridine with diethylmalonate instead of affording the expected pyridodiazepine, yielded an imidazopyridine, the structure of which was inferred from spectral data Nevertheless, the pyridodiazepine was obtained by condensing the diamino-heterocycle with malonyl dichloride.


The biological fate of reserpine.

The biological fate of reserpine. Orally administered reserpine is readily absorbed from the GI tract. During this process at least a portion of the drug is metabolized by the intestinal mucosa and then presumably is acted upon by serum esterases. Methylreserpate and trimethoxybenzoic acid are the primary metabolites which result from the hydrolytic cleavage of reserpine. Since most of the blood leaving the GI tract passes through the liver via the portal vein, hepatic metabolism would also be expected to reduce reserpine levels in the blood. The relative contributions of serum esterases versus hepatic metabolism in the biotransformation of reserpine in vivo are not known. However, very little unmetabolized reserpine is eventually eliminated in the urine. In the liver, it is quite likely that both microsomal oxidative and hydrolytic enzymes contribute to the metabolism of reserpine. It seems that microsomal oxidation (such as the demethylation of the 4-methoxy group on the TMBA moiety) must precede hydrolysis since inhibition of demethylation markedly reduces the rate of hydrolysis. In addition to oxidation and hydrolysis, conjugative reactions also must occur in liver or extrahepatic tissues since both glucuronide and sulfate conjugates of TMBA have been identified. Some reserpine molecules do seem to escape metabolism, however, since significant amounts of intact reserpine have been found in fecal samples taken from both experimental animals and human beings after either oral or parenteral drug administration. Presumably reserpine is transported from the blood via the biliary tree into the small intestine where it is either reabsorbed or eliminated in the feces. Pulmonary elimination of CO2 produced after complete oxidation of the 4-methoxy group of TMBA has also been shown to occur both in vivo and in vitro. The following may serve as a model for the relationship between the subcellular distribution of reserpine and its site of action. After a single intravenous injection most of the reserpine, probably loosely bound to plasma albumin, is distributed to tissues on the basis of their blood flow. Because of its lipophilic properties, reserpine would easily penetrate cell membranes and then bind possibly electrostatically to intracellular membrane components, particularly those rich in phospholipids. Much of the circulating reserpine would then either be metabolized or be taken up by the lipid depots of the body, leading to a rapid redistribution of the reversibly bound reserpine from the tissues. During this time a relatively small fraction of the total reserpine administered by injection would become associated with monoaminergic granular membranes in a more specific and irreversible manner. This would result in a persistent, nonstoichiometric inhibition of monoamine uptake. Such a small specific binding would not be detectable for at least 18 hr after reserpine administration, i.e., until most of the reversibly bound alkaloid had been metabolized and/or excreted...


Meiosis in perspective.

Meiosis in perspective. Our understanding of meiosis springs from two suggestions made by Weismann in 1887. One was that meiosis would be found to compensate for fertilization in the life cycles of both sexes and all organisms. The other was that the development of sexual reproduction in evolution depended on the value of meiosis in exposing the results of genetic recombination to natural selection. In confirming these propositions we were bound to discover that the properties of meiosis appear both as the causes and the consequences of evolution: it is the hinge on which turns the evolution of breeding method, reproductive habit, life cycle and hereditary structure, that is the genetic system, in all sexually reproducing species of organism. We have had three main fields of attack on our problem. First, there was the natural variation of meiosis including that of two-track hereditary within the species: here, animals took the lead. Secondly, there was the experimental field - both with genetic controls such as polyploidy and the sterilizing mutations of mitosis as well as meiosis, and with physical and chemical controls: here, the higher plants and micro-organisms have given us our great opportunities. Thirdly, we have the widening field where physicochemical knowledge and genetic control converge and collaborate. In all this work we have to be aware that meiosis works with chromosomes which always have the two functions of accomplishing evolution and of implementing its results in heredity. In consequence, the adaptation of meiosis is perpetually imperfect.


A first view of the meiotic process.

A first view of the meiotic process. In this introductory paper we have highlighted some aspects of the meiotic process which seem important to us and about which some especially interesting features have been discovered. These include the switch from mitosis to meiosis, premeiotic DNA synthesis, association of the chromosomes with the synaptonemal complex, the nature of chromosome homology in relation to chromosome pairing, the process of chromosome pairing, the regulation of meiosis as a developmental process and the process of recombination. We have indulged in speculation in the hope that it will stimulate additional discussion and research into these crucial meiotic cell divisions which link the generations in higher organisms.


The time and duration of meiosis.

The time and duration of meiosis. Ever since meiosis was recognized as a process there has been a continuing interest in its temporal aspects. Two main types of meiotic timing experiments have been conducted: first, experiments to estimate the duration of meiosis (and sometimes its stages); second, experiments to locate the sensitive stage(s) when exposure of meiocytes to various treatments can affect meiotic chromosome behaviour (e.g. pairing or recombination). Such experiments have played an important role in increasing our understanding of the meiotic process. The duration of meiosis has been estimated in about 70 organisms, including two prokaryotes (yeast and Chlamydomonas) and the following eukaryotes: 1 Basidiomycete (Coprinus lagopus), 2 Gymnosperms (Larix decidua and Thuja plicata gracilis). at least 39 angiosperms, and at least 26 animal species. The duration of female meiosis has been estimated in far fewer species than male meiosis. However, estimates of the duration of female meiosis are available for 6 angiosperms. Drosophila melanogaster, Xenopus laevis, and several mammals. Comparison of these data shows that the duration of meiosis is one of the most variable aspects of the meiotic process, ranging from less than 6 h in yeast to more than 40 years in the human female. Developmental holds at different stages of meiosis are common in plants and animals, and inevitably prolong the meiotic division. However, even among species without developmental holds, the duration of meiosis is very variable. For instance, in animals it ranges from about 1-2 days in male Drosophila melanogaster to more than 24 days in male Homo sapiens and several Orthopterans. Despite the large variation in the duration of meiosis three generalizations can be made: (i) first prophase is always very long compared with the remaining meiotic stages, (ii) the rate of meiotic development is very slow compared with the rate of development in dividing somatic meristem cells of the same organisms under  the same conditions, (iii) the duration of meiosis is characteristic of the genotype and species. Four main factors have been recognized which effect or determine the duration of meiosis, namely (1) environmental factors (e.g. temperature); (2) nuclear DNA content; (3) ploidy level of the organism; and, (4) the genotype. Because nuclear DNA content plays a major role in determining the duration of meiosis, it has been suggested that DNA influences the rate of meiotic development in two ways: first through its informational content (the genotype), and second indirectly by the physical and mechanical effects of its mass independently of its informational content (i.e. the nucleotype). Thus, the observed duration of meiosis is the result of a complex genotype-nucleotype-environment interaction. With the obvious exception of variation caused by developmental holds, changes in the duration of meiosis usually involve proportional changes in the durations of all its stages...


Recombination in male and female meiocytes contrasted. For technical reasons studies of chiasma frequency and distribution, and hence of intrachromosomal recombination, have mostly been confined to male meiosis. However, there is now sufficient comparative data on male and female meiosis, in both plants and animals, to show that the extent of intra-chromosomal recombination in some organisms may be much the same on the female as on the male side, whereas other organisms show extreme sexual divergence in this regard. The evolutionary significance of such diversity remains enigmatic.


The assembly of the synaptinemal complex. The assembly of the synaptinemal complex in the ascomycete Neottiella was studied by three-dimensional reconstruction of a late zygotene nucleus. A single banded lateral component is formed between the two sister chromatids of each homologous chromosome prior to their pairing. The central regions are pre-assembled in organized form in folds of the granular part of the nucleolus and then converted into an amorphous transport form. The latter appears to move through the nucleoplasm to sites between the lateral components of synapsing homologous chromosomes. The central region material is reorganized into blocks with a recognizable central component and attached to one lateral component. The last step in the completion of the synaptinemal complex is the association of the free surface of the organized central region with the corresponding segment of the homologous lateral component. The findings are discussed in relation to mechanisms of chromosome pairing and chiasma formation.


Homologous chromosome pairing.

Homologous chromosome pairing. Commonly accepted precepts are challenged: (1) that homologous chromosome pairing is normally mediated by nuclear envelope attachment sites; (2) that crossover site establishment awaits synaptic completion; and (3) that it is the function of the synaptonemal complex to hold homologues in register so that equal crossing over can occur, and perhaps to provide machinery for the crossover process. Although these views may eventually be shown to be true, it is felt that currently available evidence does not warrant their full acceptance, and that alternatives should be considered. As examples of alternatives the following ideas, with some supporting evidence, are suggested: (1) homologous chromosome pairing (in non-haplont organisms) may be accomplished by chance meeting of homologue segments (followed by establishment of invisible, elastic connectors) at congression for a mitotic metaphase (in many cases perhaps the premeiotic mitosis); (2) crossover sites may be established before, during, or immediately following initiation of synapsis; and (3) the synaptonemal complex may somehow function in the crossover process at the inception of its formation, but its complete deployment throughout each normal bivalent may serve some other role, such as mediation of the binding of sister chromatids apparently required for chiasma maintenance until anaphase I.


Some morphological aspects of the synaptonemal complex in higher plants. The synaptonemal complex is illustrated in electron micrographs from pollen mother cells (p.m.cs) of the following plants: Fritillaria lanceolata, Allium fistulosum, Tulbaghia violacea, Luzula purpurea, Phaedranassa viridiflora and the tulip cultivar Keiserkroon. The possibility that the lateral elements in synaptonemal complexes of plants are tubiform structures is discussed in relation to their fine structure and in the light of a deformity seen in them. An assessment of the evidence suggesting that both lateral and central elements in the complex are ribonucleoprotein structures is made. The effect of brief water treatment on the chromatin and synaptonemal complex at zygotene in p.m.cs of the Phaedranassa is discussed, particularly with reference to two precisely oriented axial strands then seen running between the lateral elements. Examination of stages of premeiotic interphase and early leptotene in p.m.cs of the Fritillaria, revealed that the axial cores laid down at leptotene are formed first in heterochromatic regions, which in this species are locked in chromocentres that persist until pachytene. Further, at leptotene the chromatin in these parts was singularly more decondensed (diffuse) than at any other period, including the premeiotic interphase, subsequent stages of meiosis and mitotic cycle in meristems. It is suggested that the diffuse state of the chromatin in chromocentres at the onset of leptotene, allows the necessary freedom of movement required to promote homologous pairing of the heterochromatic segments. Evidence of such a movement was indicated by a change in position of the nucleoli, which moved from a more central position at early premeiotic interphase to a peripheral one at the onset of leptotene, when they are seen adpressed to the nuclear envelope.


Chromosome distribution: experiments on cell hybrids and in vitro. Ostergren (1951) provided a simple explanation for both chromosome distribution in mitosis and chromosome segregation in meiosis, and more recently a molecular extension of his hypothesis has been possible. This report focuses on experimental tests of these ideas. Micromanipulation experiments on cell hybrids containing both meiotic and mitotic spindles demonstrate that differences in meiotic and mitotic chromosome behavior are determined by something intrinsic to the chromosome: meiotic chromosomes transferred to a mitotic spindle (or vice versa) behave just as they normally would. The molecular explanation postulates polarized growth or binding of microtubules at kinetochores. This has just been tested in vitro by McGill & Brinkley (1975) and by Telzer, Moses & Rosenbaum (1975), and their results are reviewed. In addition, a novel method for in vitro studies is described - mechanical demembranation of cells which is compatible with quite normal chromosome movement in anaphase. After addition of microtubule subunits to a demembranated prophase cell, chromosome orientation and movement toward an aster was observed for the first time in vitro. It is concluded that important aspects of chromosome distribution are probably understood at both the cellular and molecular levels, but final tests are still required. The outlook is hopeful indeed because the gaps in our knowledge are well known - the necessity of observations on prophase is a recurrent theme - and the means of filling the gaps are in hand.


Biochemistry of meiosis.

Biochemistry of meiosis. The process of meiosis in Lilium falls into four physiological stages - prezygotene, zygotene, pachytene, and post-pachytene. Each of these stages has distinctive metabolic characteristics. Commitment to meiosis occurs during the prezygotene interval at about the time when S-phase replication is completed. The activities following commitment are essential to synapsis inasmuch as perturbations of cells during that interval have subsequent effects on synapsis and crossing over. Just before the initiation of synapsis, a distinctive lipoprotein complex appears in the nucleus. The complex most probably functions in the process of pairing. Zygotene is marked by the delayed replication of specific intercalary segments of chromosomal DNA (Z-DNA), the replication being a necessary condition for ongoing synapsis. The replication occurs in the lipoprotein complex in the presence of a reassociation protein (r-protein). Z-DNA segments would appear to have other meiotic functions inasmuch as the replicated segments remain unligated to the body of chromosomal DNA until the beginning of chromosome disjunction. The pachytene interval is marked by an activation of endonucleolytic activity. The enzyme produces single-stranded nicks in the DNA at specific loci. These loci consist of moderately repeated segments; about 100-200 base pairs long. Extracellular agents, such as radiation, cause random nicking regardless of the meiotic stage at which they are applied. Localized nicking and repair are thus unique features of meiosis. The temporal segregation of metabolic activities concerned with pairing and crossing over and their operation in special chromosome regions constitute the most prominent features of the biochemical events associated with meiosis.


The genetic analysis of meiosis in female Drosophila melanogaster. The three major features of meiosis are first synapsis, then exchange, and finally, disjunction of homologous chromosomes; these phenomena occur before pachytene, during pachytene, and after pachytene respectively. The effects of meiotic mutants, or other perturbations, either endogenous or exogenous, on the meiotic process may be assigned tentatively to one of these intervals, based on the earliest discernible abnormality. Thus mutants exhibiting abnormal disjunction and normal exchange affect post-pachytene functions; mutants exhibiting abnormal disjunction and exchange but with ultrastructurally normal appearing synaptonemal complex affect pachytene functions; and mutants with abnormal disjunction, exchange, and synaptonemal complex affect prepachytene functions. This rationale is applied to the temporal seriation of effects of meiotic mutants and chromosomal abnormalities on the meiotic programme.


Inferences from genetical evidence on the course of meiotic chromosome pairing in plants. Meiotic chromosome pairing is a process that is amenable to genetic and experimental analysis. The combined use of these two approaches allows for the process to be dissected into several finite periods of time in which the developmental stages of pairing can be precisely located. Evidence is now available, in particular in plants, that shows that the pairing of homologous chromosomes, as observed at metaphase I, is affected by events occurring as early as the last premeiotic mitosis; and that the maintenance of this early determined state is subsequently maintained by constituents (presumably proteins) that are sensitive to either colchicine, temperature or gene control. A critical assessment of this evidence in wheat and a comparison of the process of pairing in wheat with the course of meiotic pairing in other plants and animals is presented.


Ribosomes, membranes and organelles during meiosis in angiosperms. Evidence is presented from both observational and analytical techniques indicating profound changes to take place in the ribosome population during male and female meiosis in some flowering plants. During microsporogenesis these appear to involve the elimination of the major part of the ribosome complement early in the meiotic prophase, and its subsequent restoration by the disintegration in the tetrad cytoplasm of 'nucleoloids', themselves synthesized in the nucleus during late prophase. In female tissue the process is essentially similar except for differences in the restoration of the ribosome population. Immediately before the eradication of the ribosomes in both sexes, a sizeable proportion of the meiocyte cytoplasm is encapsulated by double, or multiple unit membrane profiles. Significantly this cytoplasm remains unaffected by the agents responsible for the degredation of the ribosome population. These events are also reflected in the organelle populations where cycles of dedifferentiation and redifferentiation take place. In view of evidence from other organisms, it is considered unlikely that these cycles are in any way a prerequisite of meiosis, but more a characteristic of cells undergoing major changes of phase, where a cytoplasmic 'clean-up' is required before the next stage of growth may begin.


Meiosis in Bombyx mori females.

Meiosis in Bombyx mori females. Crossing over is absent in oocytes of the silkworm, Bombyx mori. Synaptonemal complexes are present during pachytene between the paired chromosomes. At leptotene, lateral components of the synaptonemal complex are attached in a bouquet to a limited region of the nuclear envelope. Before completion of lateral components, synaptonemal complex formation begins at the nuclear envelope. With synaptonemal complex formation proceeding from both ends bivalents occasionally become interlocked. After pairing is completed, the bouquet arrangement is dissolved possibly as a result of a flow of the inner membrane of the nuclear envelope thereby separating the telomeres. After the telomeres are released from the nuclear envelope, material is deposited onto the lateral components of the synaptonemal complex. The modified synaptonemal complexes are retained by the bivalents until metaphase I. It is suggested that these modified synaptonemal complexes substitute for chiasmata in order to ensure regular disjunction of homologous chromosomes in the absence of crossing over.


Meiosis in a temperature-sensitive DNA-synthesis mutant and in an apomictic yeast strain (Saccharomyces cerevisiae). It is shown that in the temperature-sensitive yeast mutant (Saccharomyces cerevisiae) spo 11 at the restrictive temperature of 34 degrees C. (1) premeiotic DNA synthesis is nearly completely blocked; (2) the nucleus enters meiotic prophase indicated by the formation of axial cores and polysynaptonemal complexes; (3) the kinetic apparatus functions normally at meiosis I and II; (4) early spore formation occurs in nearly all cells but it is variable and all spores eventually degenerate. It is concluded that chromosome replication is not a prerequisite for the functions listed above. The apomictic yeast strain 4117 produces 2 diploid spores. It is shown that a diploid which produces 2-spored asci, synthesized from 4117, no. 5, and an adenine requiring strain (1) has a normal meiotic prophase with abundant synaptonemal complexes; (2) has only one meiotic spindle; (3) has spores which form red clones more frequently than normal or u.v.-treated vegetative cells form ade/ade red sectors through mitotic recombination. It is concluded that this apomictic yeast has maintained meiotic prophase, but that one of the two meiotic divisions is suppressed.


Recombination and meiosis.

Recombination and meiosis. Although exchanges between sister chromatids are common in mitotic cells, those involving homologous chromosomes are rare. Since recombination between homologues is one of the functions of meiosis, it follows that one aspect of the differentiation of the meiocyte involves the synthesis of proteins or enzymes which facilitate synapsis and exchange. Mutants are known which seem to have constitutive levels of mitotic recombination between homologues, and these may be defective in the mechanism which normally represses mitotic recombination. It has been proposed that one component of the synaptonemal complex (s.c.) is a filamentous pairing protein with DNA binding sites which are base sequence specific. Synapsis occurs because the distribution of these sequences is the same in homologues. When only non-homologous chromosomes are present, as in haploid meiosis, only weak pairing can occur, since the base sequences are largely out of register. Although certain features of recombination at the molecular level are known, none of the models so far proposed suggest an explanation for interference between crossovers. It is suggested that interference may depend on the presence of a limited amount of another DNA binding protein which is specifically located within the s.c. A crossover between naked DNA molecules is initially a weak structure, which must be later converted into a visible and mechanically strong chiasma. It is assumed that this stabilization of a crossover is achieved by the DNA binding protein, which can diffuse freely within the s.c. and bind cooperatively to any recombinant DNA molecules within it. Depletion of the binding protein within the vicinity of a crossover makes it unlikely that the second crossover can be formed nearby.


Variation in the spire index of some coiled gastropod shells, and its evolutionary significance. The spire index (height/maximum diameter of shell) is a fairly adequate measure of the shape of the coiled shell of most terrestrial and freshwater gastropod shells but less so in complex marine shells with thorns, flanges and spouts. In this study, only adult free-crawling forms with several whorls, able to retract completely into the shell, are considered. In the Stylommatophora of the Western European terrestrial fauna the distribution of the spire index is markedly bimodal, the modes, with values of about 3 and about 0.5, corresponding respectively to shells with a high to very high spire (and small spire angle) and those varying from more or less globular or trochoid to very flattened and disk-like (spire angle from 60 degrees to 180 degrees). The same two modes are found in the taxonomically different terrestrial stylommatophorans of the U.S.A., and in the faunas of Puerto Rico (Caribbean) and New Caledonia (southwest Pacific). Basommatophorans also show two, rather different, modes. North American marine archaeogastropods are mainly equidimensional but with a few disk-like forms and a very few high-spired ones, marine mesogastropods are mainly high-spired but with disk-like forms, neogastropods high-spired, and relevant euthyneurans sharply bimodal, like the stylommatophorans. Fossil archaeogastropods of the Palaeozoic were much more various at first than modern forms. There is some indication that they became restricted in variety as caenogastropods became abundant, but also that the proportion of marine disk-like shells has decreased markedly since the Palaeozoic. Modes of h/d are characteristic of large taxonomic groups but not taxonomically restricted since given values may appear as specific, generic or subfamilial variants from a mode, and appear sporadically in unrelated forms. There is also no broad association between modal value and broad ecological characters. Since nearly all values do occur in some group or other, no mechanical requirement can be invoked to explain such variation. In the land Stylommatophora enough is known of the broad ecology to suggest that in extreme habitats species with very different size or shell-shape may occur together, and that generalized feeders with similar shells may show separation, ecological or geographical (but in that case, also ecological). Since different shapes of shell will have different mechanical characteristics when considered as burdens to be carried, it is suggested tentatively that they may be related to the positions in which different species normally walk and hence to their preferred feeding places. This would explain an apparent tendency for different taxonomic groups to occupy the same part of the scatter of h/d in different regions of the world, for many groups in the same region to occupy different portions of the scatter, and perhaps the apparent exclusion by caenogastropods of archaeogastropods from part of the scatter since the Palaeozoic. It is argued that the distributions discovered are explicable only by natural selection.


Pigment epithelial ensheathment and phagocytosis of extrafoveal cones in human retina. The association between extrafoveal cone outer segments and pigment epithelial cells was studied by transmission electron microscopy in three human retinas; ages 5,45 and 60. The pigment epithelial apical surface from a fourth human retina, age 38,was viewed in the scanning electron microscope. Multiple villous-like apical processes protrude from the pigment epithelium into the space above each cone. Sometimes one or more of these processes is sheet-like in form and contains a wealth of intracellular organelles, including mitochondria. One or more of the villous-like procesess reaches the cone and expands to ensheath the upper one-third of the outer segment. Llike vertebrate rods, extrafoveal human cones shed their terminal disks in packets and these packets are phagocytosed by the ensheathing apical processes. The phagosomes then ascend in the processes toward the pigment epithelia soma. Digestion of phagosomes appears to begin in the apical processes.


Relationship between neurotransmitters and atherosclerosis. Dyslipemia and finally the producing of atherosclerosis signal some modulation disturbances in neurotransmitters by the onset of a permanent incapacity of the organism to coordinate the adapting mechanism against the over-high activity of stress factors. Neurotransmitters and related substances facilitate and modulate energy and information in biosystems, assigning an important role to central control as noradrenaline, serotonin and other biogenic amines mediate emotional stress.


[New views referred to gamma-glutamyl-transpeptidase (author's transl]. The AA. have observed some patients suffering from persistent chronic hepatitis, aggressive chronic hepatitis, severe virus hepatitis, hepatic cirrhosis, hepatic metastasis, cholecystolithiasis, hepatic abscess, congestic heart disorder, alcoholism also patients treated with barbiturics and benzodiazepine, comparising in the meanwhile gamma-glutamyl-transaminase. They would suggest a new interpretation: the observed enzyme was higher in the obstructive diseases, gamma-GT also notable higher in the cellular hepatic diseases (hepatitis, cirrhosis and so on). In their opinion gamma-GT should be a regular enzymatic screening for liver diseases, but should not anyway eliminate the till now used enzymes.


Alpha-adrenergic blockers on ventricular automatism in rat heart. The role of the alpha-adrenergic receptors in the genesis of cardiac arrhythmias induced in the isolated rat right ventricle has been studied. The administration of six alpha-adrenergic blocking agents (phenoxybenzamine, dibenamine, phentolamine, tolazoline, azapetine and SY-28) did not alter the automatism induced. Even when can not be excluded the existance of alpha-adrenergic receptors in the rat ventricle, it is clear that alpha-blocking drugs are ineffective to abolish the arrhythmias induced by an increase in the activity of the Purkinje fibers.


Cardiorespiratory and behavioral reactions to the lidocaine-induced convulsions in the dog. Central nervous system (CNS) reactions to intermittently infused lidocaine HCl (i.v.) were evaluated from cardiorespiratory and behavioral responses in 33 mongrel dogs. Threshold convulsive doses were established for each of three distinct and predictable seizure patterns. The first seizure activity observed was tonic extension (TE) which occurred at an infused lidocaine dose of 12.2+/-0.6 mg/kg followed by running activity after 22.7+/-0.9 mg/kg lidocaine was given. The threshold for intermittent tonic-clonic seizures (ICS) occurred at an infused lidocaine dose of 33.3+/-1.5 mg/kg. Mean blood pressure and pulse pressure increased at the onset of TE and ICS, with a decline in arterial pH and PCO2 during the ICS. No relationship was found between the animals' acid-base status and the ICS threshold. Toxicity to lidocaine in the dog is expressed by distinct behavioral responses suggesting lidocaine may affect various parts of the CNS. The mongrel dog appears to be a satisfactory and simple model system to evaluate lidocaine toxicity from behavioral and cardiorespiratory responses.


Inhibition by naloxone of tolerance and dependence in mice treated acutely and chronically with morphine. The inhibition by naloxone of tolerance and dependence in morphinized mice is dose- and time-dependent. In animals receiving a single, large dose of morphine, partial inhibition by naloxone of the analgesic effect results in partial development of tolerance and dependence. This relationship appears to be true for animals which have been treated with morphine chronically. Complete and sustained blockage of morphine receptors by naloxone is required for complete inhibition of the development of tolerance and dependence.


Exercise-induced bronchoconstriction in patients with bronchial asthma. Its prevention with an antihistaminic agent. 14 asthmatic patients developing regularly exercise-induced bronchoconstriction were subjected to a submaximal exercise on a bicycle ergometer. On the first day the exercise was not preceded by any medication; on the second, 50 mg thiazinamium was given, and on the third day 2 mg atropine was given before the exercise. The changes in the calibre of the bronchi were assessed with a Wright peak flow meter. With thiazinamium a complete protection against the bronchoconstriction was observed in 12 patients, in one the protection was partial and in an other no beneficial effect of the drug was found. It seems that protection given by thiazinamium was due to its antihistaminic property and not to the anticholinergic one, as among 10 patients protected by thiazinamium, only 2 were also protected by the atropine.


[Beta blocking agents in the treatment of algo-neuro-dystrophies. Apropos of 34 cases]. The authors report results of a series of thirty four cases of algo-neuro-dystrophy treated with beta blockers. This treatment produced favorable results in thirty out of the thirty four cases and the mode of action is discussed.


Comparison of rimiterol and terbutaline, given by aerosol, in a long-term study. In a double-blind long-term study, regular inhalations of a short-acting selective beta2-stimulator, rimiterol, was compared with a long-acting one, terbutaline. The trial comprised 60 patients with chronic obstructive lung disease, all patients were on a small dose of an oral beta2-stimulator. Both drugs were regularly given in aerosol form with a minimum dose of three inhalations three times daily. The main purpose was to study subjective and objective side effects. Haematological, hepatic and renal functions were screened for toxicity. Consumption of spray was recorded. No side effects occurred. There was no evidence of development of isoprenaline resistance. The consumption of spray was the same in both groups. In this study, regular inhalation treatment of rimiterol seemed to be as effective as terbutaline in long-term bronchodilator therapy.


[Vasculitis in hepatitis B infection].

[Vasculitis in hepatitis B infection]. Personal observations have confirmed the frequent association of HB-infection with certain forms of vasculitis. 4 of 11 patients with polyarteritis nodosa were repeatedly found to be HBs-Ag positive and had chronic hepatitis of varying severity. In patients with giant cell arteritis (polymyalgia rheumatica and temporal arteritis) anti-HBs was found more frequently than in controls, especially when examined within 6 months after onset of symptoms (7 of 20 equal 35% had anti-HBs, versus 6% of controls). Several lines of evidence point to the important role played by circulating HBs-Ag/anti-HBs complexes in the development of HB-associated vasculitis.


[Role of neuropsychiatric pathology and pharmacology in neuroendocrinologic research]. Experimental, pharmacological and clinical data are presented suggesting that neurotransmitters, neurohormones and adenohypophyseal hormones have effects respectively on aterior pituitary and on the CNS. The related functional hypothesis are proposed and discussed.


Direct resorption of bone by human monocytes. Cultured human peripheral blood monocytes stimulate the release of bone mineral and matrix from killed long bones of fetal rats. These effects were inhibited by cortisol but were not altered by hormones that normally stimulate osteoclastic bone resorption. There was no evidence of morphologic differentiation of the monocytes into osteoclasts during bone resorption.


Prelytic damage of red cells in filtrates from peroxidizing microsomes. When liver microsomes are incubated in the presence of reduced nicotinamide adenine dinucleotide phosphate (NADPH), their constituent lipids undergo peroxidative degeneration. If erythrocytes are present in such a peroxidizing system, they hemolyze. Filtrates obtained by ultrafiltration of peroxidizing microsomal systems were found to have the capacity to produce prelytic damage in red cells. Filtrates obtained from microsomes that had not undergone peroxidative lipid decomposition were inert. The toxic activity in the active filtrates was not due to continuing oxidation of NADPH nor to continuing liver microsomal lipid peroxidation. Neither the chemical identity of the toxic product or products in active filtrates nor the mechanisms involved in the erythrocyte damage are known at this time.


Acute erosive gastritis induced by aspirin, ketoprofen, ibuprofen, and naproxen: its prevention by metiamide and cimetidine. Aspirin, ketoprofen, ibuprofen, and naproxen all produced acute gastric erosions in rats. Aspirin produced significantly more erosions than ketoprofen, ibuprofen, or naproxen. There was no significant difference between the effects of ketoprofen, ibuprofen, and naproxen. Aspirin and naproxen produced a synergistic effect at higher dosage. Metiamide and cimetidine were effective in preventing this type of experimental acute erosive gastritis.


Human intestinal helminthiases in East Timor. In a study of 210 people from all age groups in the Venilale District of East Timor, 49% had Ascaris lumbricoides, 1% Trichuris trichiura and 67% hookworm infection. There were high Ascaris infection rates among some of the children, but the Trichuris and hookworm rates were almost uniformly low. The factors responsible for these rates are enumerated, and the complex interaction of the factors is discussed. The relative lack of shade and the well-drained limestone soil are probably in large measure responsible for the generally low helminth prevalence. Ascaris was the principal cause of eosinophilia. It was not possible to relate any other haematological or serological findings to the helminths. Apart from the high Ascaris infections in young children, it is not thought that these helminths constitute a heatlh problem.


The influence of coronary arterial pH on myocardial oxygen demand. The purpose of this study was to examine the magnitude of the influence of coronary arterial pH (pHa) on myocardial oxygen uptake (MV 02). In order to isolate and control the recognized determinants of MV02, a perfused heart preparation was developed which permitted control of heart rate and pressure and flow work. A perfusion system was used which allowed independent regulation of O2 N2 and CO2 flow to a membrane lung and precise control of coronary blood flow. Myocardial oxygen delivery (Ca02 x flow) could be held constant (+/- 1%) during 4 hours of perfusion. Catheter decompression of both ventricles prevented any external pressure or flow work. Blood temperature was maintained at 37.27 +/- 0.07degrees C. Perfusing blood pH was related initially to spontaneous heart rate in five dogs: pulse = 82 pH - 487. In 12 subsequent animals heart rate was fixed. MV02 was directly and significantly related to coronary arterial pH in all animals studied: MVO2% = 109 pH - 143 (r = 0.823). An increase in pHa of 0.1 will increase MV02 by 10.9%. This study isolates pH as a determinant of myocardial oxygen uptake and indicates that progressive alkalosis induces increased myocardial oxygen uptake. This must be recognized in the treatment of patients with compromised myocardial function and rerional areas of ischemia.


Distribution of acid phosphatase activity in the larval stages of Wuchereria bancrofti, Brugia malayi, B. pahangi and Dirofilaria immitis in the mosquito. The histochemical distribution of acid phosphatase in microfilariae and in the larval stages of four mosquito-borne filariae: Wuchereria bancrofti, Brugia malayi, B. pahangi and Dirofilaria immitis was studied using naphthol AS-TR-hexazonium technique and light microscopy. Accurate differentiation between microfilariae of the four species could be made on the basis of their patterns of acid phosphatase activity. In contrast to microfilariae in the blood, the larval stages in the mosquito exhibited different patterns of acid phosphatase activity which were characteristic for each developmental stage. In the first-stage larva, maximum acid phosphatase activity was found in the anal vesicle, the growing anal membrane (anal plug), buccal cavity, forming intestine and rectum. In the second-stage larva, acid phosphatase activity was present throughout the alimentary canal, particularly in the section of the intestine and rectum. In the infective third-stage larva, the whole body stained densely red. The reaction for acid phosphatase in the excretory cell complex of W. bancrofti and of both species of Brugia gradually decreased in intensity and disappeared completely towards the end of the first-larval stage, whereas in D. immitis a strong reaction in this area persisted throughout the larval life in the mosquito. The presence or absence of enzymic activity in the excretory cell complex and in the Mundgebilde (amphids) of the developing larvae can be used as an adjunctive diagnostic method.


Analysis of vasoactivity of local pH, PCO2 and bicarbonate on pial vessels. The mechanism by which the local effect of CO2ON pial arterioles is exerted was examined in anesthetized cats equipped with a cranial window for the direct observation of the microcirculation of the parietal cortex. The dilation of pial arterioles in response to application of artificial cerebrospinal fluid with low pH was the same whether or not the PCO2 of the solution was maintained in the normal range or markedly increased. The constriction of pial arterioles in response to application of artificial cerebrospinal fluid with high pH was the same whether or not the PCO2 of the solution was maintained in the normal range or markedly decreased. Finally, pial arterioles did not change their caliber in response to application of cerebrospinal fluid with unchanged pH but markedly increased or decreased Pco, or bicarbonate ion concentration. These results show that the action of CO2 on cerebral vessels is exerted via changes in extracellular fluid pH and that molecular CO2 and bicarbonate ions do not have independent vasoactivity on these vessels.


Effect of carotid artery ligation on regional cerebral blood flow in normotensive and spontaneously hypertensive rats. Regional cerebral blood flow (rCBF) was measured in normotensive rate (NTR) and spontaneously hypertensive rats (SHR), in a lightly anesthetized state and with control of PaCO2 by artificial ventilation. Without carotid artery ligation, NTR and SHR showed almost identical rCBF values and distribution, despite significantly elevated levels of blood pressure in SHR. Bilateral carotid artery ligation, however, caused much more pronounced decreases of rCBF (ischemia) in SHR than NTR, in regions supplied by the carotid artery. The reduction of rCBF in SHR was rather homogenous and symmetrical. Mechanisms causing the differences between NTR and SHR are discussed.


Aggregation of calcium oxalate crystals: effect of urine and various inhibitors. The influence of various factors on aggregation of calcium oxalate crystals in vitro was determined. Aggregation was assessed by filtering the crystal suspension and measuring the flow rate through a filter. 10% urine completely inhibited aggregation. Orthophosphate and magnesium at concentrations occuring in urine had no effect. Citrate had no effect at 10(-4) M ,but did inhibit at 10(-3) M. The latter effect is probably due to calcium binding. Pyrophosphate and disodium dichioromethylene diphosphonate (C12MDP) inhibited strongly at 10(-4) M, disodium ethane-1-hydroxy-1,1-diphosphonate (EHDP) at 10(-5) M, whereas pentanemonophosphonate had no effect. Uromucoid also did not show any inhibitory activity. Studies by means of heat inactivation, ultrafiltration and fractionation on DEAE-cellulose and gel-filtration indicated that the inhibitory activity was heterogenous and that the major part was larger than 10 000 daltons.


[Use of preparations with sympatholytic activity for prevention and treatment of postoperative intestinal paresis]. For prophylaxis and treatment of postoperative intestinal paresis the authors employed in 1059 patients gangliolytics and drugs of sympatholytic action -- benzohexonium, aminazine, pyrroxane. An early sympathetic blockade after abdominal surgery was found to be effective both with respect to the prophylaxis of intestinal paresis and in treatment of grave functional disturbances of enteric motility, that develop in different abdominal complications.


[Determination of the effective concentration of Jodonal a for the disinfection of the skin and teats after milking]. The bactericidal effectivity of Jodonal A in 1:10, 1:5, and 1:3 solutions was tested on human skin and on the teats of cow mammary glands. The 1:3 dilution ratio proved best for three-minute exposure. Jodonal A used in this concentration in 522 cows for the post-milking disinfection of teats for 10 months exerted no harmful effect on the skin of the mammary glands.


[Devitalizing effect of Jodonal A in vitro on bacteria subject to a short-term exposure]. In a three-minute exposure in vitro Jodonal A devitalized a culture of serological group B streptococci in a 2% concentration, Staphylococcus aureus in a 16% concentration, Pneumococcus in a 4.5% concentration, Corynebacterium pyogenes in a 2.5% concentration, Pseudomonas aeruginosa in a 3% concentration, and Klebsiella pneumoniae in a 2% concentration. Hence Jodonal A concentrations higher than 16% should be tested for udder teat disinfection after the removal of teat cups.


[Acid gamma-amylase of rabbit and human brain]. Preparations of acidic gamma-amylase, which cleaved glycogen and maltose, were isolated from human and rabbit brain tissues. The specific activity of the gamma-amylase preparations from human brain was approximately twice higher than the activity of the enzyme from rabbit brain. In degradation of glycogen gamma-amylases from human and rabbit brain had the pH optima at pH 4.9 and 4.6 and with maltose as a substrate- at pH 4.3 and 4.1, respectively. gamma-Amylases from both sources possessed the high stability in presence of monovalent cations. K+ distinctly increased the cleavage of glycogen by gamma-amylase from human and rabbit brain. alpha, alpha-Trehalose and alpha-menthyl glucoside proved to be inhibitors of the glucoamylase activity of the enzymes from both sources. Km values of the gamma-amylases for glycogen were equal to 19.3 mM 19.8 and for maltose -5.54 mM and 5.78 mM, respectively. The data obtained suggest that acidic gamma-amylases from human and rabbit brain are similar to acidic gamma-amylases from other sources.


[Intracellular localization of the processes of biosynthesis and degradation of NADP in skeletal muscle]. In studies on intracellular NADP localization the process of NADP biosynthesis was observed in mitochondria and hyaloplasm of rabbit sceletal muscle cells. This synthesis was not found in microsomal and nuclear fractions. The seasonal alterations in the NAD-kinase activity were established: in autumn and winter months NADP synthesis proceeded at the maximal rate in hyaloplasm; in sping months the higher specific activity was observed in mitochondrial fraction. The rate of NADP synthesis was 2-5 times lower in initial and reconstructed (hyaloplasm+cell organelles) homogenate then in hyaloplasm, among the enzymes, degrading the NADP molecule in sceletal muscle, the highest activity was exhibitel by nucleosidase, which was localized mainly in mitochondria and microsomes. Mechanisms for regulation of the rate of NADP synthesis and degradation in cytostructures of rabbit sceletal muscles are discussed.


[Isolation of the islands of Langerhans from rat pancreas and determination of proteolytic activity in them]. A modified method for isolation of Langerhans islands from rat pancreas is described. The islands obtained were free from acinous tissue as shown by means of an amylase test and by microscopy. In homogenates of the islands proteolytic activities were observed (pH optimum at 5.3--5.5 and 6.9--7.2).


[Pyridine nucleotide content in the brain and myocardium of rats under combined effect of hypercapnia, hypoxia and cooling]. In experiments with rats, subjected to single and repeated simultaneous effect of hypercapnia, hypoxia and cooling, contents of pyridine nucleotides (NAD, NADP, NAD-H2 and NADP-H2) and macroergic substances were studied and also the activity of dehydrogenases of the pentose pathway was determined in brain and myocardium. In brain NADP was not practically determined and in heart its content was increased after the first and the second treatments. Content of NADP-H2 was distinctly decreased in both tissues after the single treatment. NAD was not altered in the tissues in all the periods studied. The amount of NAD-H2 was decreased in brain after the single treatment and it was increased in myocardium after the repeated one. In the activity of dehydrogenases marked alterations were not observed. Total macroergic substances were not altered in brain after the single treatment and after the repeated one they were increased mainly due to the ATP increase. In myocardium total macroergic substances were decreased after the both treatments.


[Adenyl cyclase and adenosine-3',5'-monophosphate phosphodiesteraze: their nature, properties and regulation]. Modern data on the nature, properties and pathways of regulation enzymes, participated metabolism of cyclic, adenosine-3',5'-monophosphate, are described. Much consideration is being given to the problem of regulation of the phosphodiesterase activity due to the effect of Ca2+-binding proteins.


[Chemiluminescence of the blood serum in the presence of divalent iron salts]. On incubation of diluted blood serum with ferrous ions kinetics of chemiluminescence, typical for lipid containing systems, was observed. It comprised several sequental steps: quick flash, inhibition of the chemiluminescence, slow flash with subsequent steady-state luminescence. At each step of the phenomenon a correlation was found between the intensity of chemiluminescence, the rate of accumulation of products of lipid peroxidation (malone dialdehyde) and concentration of Fe2+ in the mixture. The data obtained suggest that chemiluminescence of blood serum in presence of Fe2+ is due to lipid peroxidation in the serum. Kinetics of the reaction and shape of the chemiluminiscence curve depended upon a number of factors: dilution of blood serum, concentration of Fe2+ added, temperature, pH and (if blood plasma was used) type of an anticoagulant use. Only in blood lipoproteins, mainly in beta-lipoproteins, the distinctive pattern of peroxidation was developed with simultaneous accumulation of malone dialdehyde, oxidation of ferrous ions and ultralow chemiluminescence. In protein fraction of blood serum addition of Fe2+ caused only the quick splash of chemiluminescence without the malone dialdehyde production.


[Androgen participation in realizing the action of hydrocortisone and insulin on tyrosine-alpha-ketoglutarate transaminase synthesis in rat liver mitochondria]. Castration of adult rats did not distinctly alter the tyrosine alpha-ketoglutarate transaminase activity in liver tissue mitochondria. Administration of hydrocortisone caused the more pronounced increased of the tyrosine alpha-ketoglutarate transaminae activity in liver tissue mitochondria of young males as compared with the adult intact rats. Castration of adult rats did no alter stimulating effect of the glucocorticoid. Insulin decreased the stimulating effect of hydrocortisone on the synthesis of the synthesis of the enzyme in liver tissue mitochondria of young and adult castrated males. Insulin decreased the effect of hydrocortisone in adult castrated rats, provided with excess of testosterone propionate and did not change the effect in adul intact animals.


[Purification and properties of the serotonin-stimulated adenylate deaminase from the mitochondrial fraction of rat liver]. A method is described for partial purification of structurally bound adenilate desaminase from rat liver tissue mitochondria; the enzyme was stimulated by parenteral administration of serotonine. The enzymatic preparations obtained desaminated AMP, 2',3'-AMP and adenosine, but they did not effect on ATP, 2',3'-cycloAMP or 3',5'-cycloAMP. The maximal rate of desaminating of these substances by AMP-desaminase, stimulated with serotonine, exceeded approximately 1.4-fold the same values, which were obtained for the enzymatic preparations from liver tissue mitochondria of rats, administered with physiological solution. Mitochondrial serotomine-stimulated adenilate desaminase was differentiated from the other soluble adenilate desaminases by some properties; the enzyme was likely to participate also in the regulation of nucleotides balance in the organism.


[Methylmalonic acid excretion in experimental B2-avitaminosis in rats]. Providing of rats with a diet, deficient in vitamin B2 within 2 and 5 weeks, was not shown to be accompanied by an increase in excretion of methylmalonic acid. In the animals some tendency to the increased excretion of methylmalonic acid was observed within 8 weeks of the diet. The data obtained suggest that the test for excretion of methylmalonic acid was the highly specific as a pattern of supply with vitamin B12. The possible role of vitamin B2 and flavoproteins in biosynthesis of coenzyme forms of vitamin B12 is discussed.


[Isoelectric focusing in a boroborate buffer-mannitol system (BBM)]. The data of the following study of isoelectric focusing in the system 'buffer--nonelectrolyte' are described. The method was shown to be employed for study of proteins, when human serum albumin was used as a model. A standard method and an apparatus device are proposed for the analytical isoelectric focusing of proteins both in the wide (pH 4.00-8.50) and in the limit (PH 4.50-6.00) PH regions. Advantages and limitations of the method are discussed as compared with the method of isoelectric focusing in ampholines.


[Acid-base and water-electrolyte status in animals with experimental tumors]. It is noted that rats with Heren carcinoma show alkalization of blood, decreased pH levels of the urine, hypokalemia, hypocalcemia, hypomagnesiemia, sodium and water retention, increased kalium level in the liver. Analogous changes are observed in rabbits with Brown-Pearce carcinoma. The organism of tumor-bearing rats responds to stress effects otherwise than the organism of normal animals.


[Kinetic properties of partially purified glucosephosphate dehydrogenase of human erythrocytes]. Partially purified glucose-6-phosphate dehydrogenase was isolated from small amounts of human erythrocytes (15-20 ml). The Km value for glucose-6-phosphate was 35.0 +/- 3.0 micronM, the Km for NADP was 4.27 +/- 0.3 micronM. The optimal activity of the enzyme was at pH 9.0. Glucose-6-phosphate dehydrogenase, dialyzed in presence of 1-10(-5) M NADP, had critical temperature about 52 degrees within 10 min of incubation; without NADP it was at 45 degrees. The method for isolation and purification of the enzyme was modified.


[Method for the direct spectrophotometric determination of the rate of the tyrosine hydroxylase reaction]. A rate of the tyrosine hydroxylase reaction was estimated by an increase in absorption at 335 nm, which was caused by oxidation of pterin cofactor 6,7-dimethyl-5, 6, 7, 8-tetrahydroxypterin (DMPH) coupled with the convertion of the substrate 1-tyrosine into dihydroxyphenylalanine. At pH 6.2 the ratios of molar extinction were as follows: in trisacetate ADMPH4-1370, ADMPH2-5350; in tris-malate tadmph4-1250, admph25300. the enzyme, associated with membranes, had the Km value for Tyr-0.045 mM, the Km for DMPH4 was 0.18 mM; the soluble enzyme had Km for Tyr-0,050 mM, the Km for DMPH4 was 0.74 mM. The stoichiometry of the reaction was 1:1 (I mole DOPA per I mole of DMPH2 formed).


[Neurohumoral influences of steroid hormones on sexual responsiveness in women (author's transl)]. An analysis has been carried out on the basis of endocrinological and psychosomatic studies of the influence of steroid hormones, acting via probable transmitter substances, on the sexual response in women. From a review in the literature it can be concluded that among other factors the endocrine state of the women determines her sexual response and behaviour. However, the present lack of specific psychological tests is pointed out, as well as the absence of relevant hormonal data to the sexual sphere, both normal and pathological.


[The influence of socio-economic factors on the results of a prematury-Dysmaturity prevention programme (author's transl)]. All high-risk gravidae with regard to prematurity and dysmaturity (PDP programme) were collected over a time-limited period. More than two thirds (n = 72) of these women were submitted to intensive care (PDP group); one third (n = 33) (control group) refused intensive care. Furthermore, socio-economic factors were taken into consideration in this study and appropriate classification into 4 groups was undertaken. Gravidae of a higher social class were more often willing to undergo intensive care than gravidae of a lower class. In the PDP group 75% of the gravidae were delivered after the end of the 36th gestational week and 51% of the gravidae in the control group. A similar relationship was found in regard to the birth weight of the newborn infants: in the PDP group 74.4% of the babies weighed over 2500 g at birth in contrast to the respective figure of 42.9% in the control group. However, this socio-economic study shows that the results of intensive care are much more successful in women from a lower social stata than in women from a higher social class.


[Role of lipid peroxides in the pathogenesis of arteriosclerosis. Detoxication of lipid peroxides by the glutathione-peroxidase system in the aorta]. In aorta of intact rabbits the high activity of glutathione-peroxidase, which detoxicates lipoperoxides, was observed. In aorta of animals with pronounced experimental atheromatosis the enzyme activity did not distinctly differ from the control values. The animals with high initial content of glutathione-peroxidase in aorta were shown to be less subjected to the impairment in alimentary atherosclerosis.


[New aspects in diagnosis and therapy of placental insufficiency. Placental perfusion measurements; placental perfusion test (PPT) and betamimetic long term treatment (clinical and experimental data (authors transl)]. The rate of utero-placental blood flow depends on functional components (perfusion pressure and flow resistance within the area of the vascular bed of the placenta), as well as on morphological factors (regressive changes in the placenta). Different primary maternal conditions and diseases may lower the rate of placental flow, leading to placental insufficiency; the highest percentage, by far, of placental dysfunction is found in patients suffering from gestosis. Hypocirculation initially present in cases of EPH gestosis and caused by arteriolar spasms triggers off a vicious circle involving placental infarction and severe reduction in the utero-placental perfusion rate. This in turn leads to fetal hypotrophy, a high rate of premature births and perinatal mortality. Verification of HPL, HCG, alpha-Fetoprotein or E3 in maternal serum and amniotic fluid or urine greatly improved the recording of partial placental functions. Along with ultrasonic biometry, cardiotocography and amnioscopy, these hormonal parameters allow only indirect assessment of the placental function. On the other hand, measurements of the utero-placental flow offers a direct approach. In order to evaluate the placental flow measurements it is imperative to obtain a curve indicating the course over the last third of the pregnancy-in addition to establishing a general normal range. In case of placental insufficiency, it is necessary to determine whether this is due to functional disorders alone, or to more extenisve morphological changes. A placental perfusion test (PPT) was developed in order to make this distinction. Beta2-mimetic treatment is indicated if functional factors predominate, whereby it appears essential to obtain the requisite experimental data for precise quantification of beta-mimetic action.


[Physiology and biochemistry of streptomycetes. VIII. Esterase activity and production of turimycin in cultures of Streptomyces hygroscopicus JA 6599]. Esterase in cell-free extracts of Streptomyces hygroscopicus JA 6599 has a temperature-optimum of 35 degrees C, a pH-optimum with p-nitrophenylacetate as substrate at pH 7.7--8.1, with alpha-naphthylacetate at pH 7--9. Michaelis constants in cell-free extracts: with alpha-naphthylacetate Km = = 0.71 mM, with p-nitrophenylacetate Km = 0.21 mM. Phenylesters were better hydrolyzed than naphthylesters, phenylacetate was best hydrolyzed; beta-naphthylacetate was better hydrolyzed than alpha-naphthylacetate. Among the naphthylesters the ester of propionic acid was hydrolyzed best. Caprylate, stearate, and 0,0-diethyl-0-(p-nitrophenyl)-phosphate inhibit the splitting of alpha-naphthylacetate. A comparison with esterases of other biological origin shows that the enzyme studied can be a carboxylesterase (E.C.3.1.1.1.). In cultures of JA 6599 V13 and JA 6599-6 the change of esterase activity during the fermentation was determined. We found a carrelation between the enzymatic activity and the antibiotic-concentration in the culture medium.


[Effect of psychotropic preparations on the activity of Ca- and Mg-dependent ATPase of the sarcoplasmic reticulum]. In sarcoplasmic reticulum of rabbit skeletal muscles the activity of Ca2+, Mg2+- dependent ATPase was distinctly inhibited under effect of neuroleptic drugs - derivatives of phenothiazine and butyrophenone. The effect of tricyclic antidepressants was less pronounced. Tranquilizers (derivatives of 1,4-benzodiazepine) inhibited the enzyme, but trioxazin was only slightly active. High concentrations of lithium salts and of psychostimulants caffeine and corasole were found to stimulate the Ca2+, Mg2+-ATPase activity; low concentrations of the substances slightly inhibited the enzyme. The blocking effect of psychotropic drugs was more distinct, if the enzyme preparations were previously treated with ATP.


[Use of potentiometric titration at constant pH for determination of the activity of lipoprotein lipase]. A method is developed for determination of the lipoprotein lipase activity. The method is based on the steady state potentiometric titration at constant pH value of higher fatty acids, liberated during the hydrolysis. An oil emulsion intralipid, activated by human blood serum, was used as a substrate. The sensitivity of the method was equal to 0.004-0.010 micronM of fatty acids per min. The reproducibility of the results was 2-5%. This simple and rapid method enabled to study kinetic of reactions, catalyzed by lipoprotein lipases.


NAD(P)H utilization in the reduction of pyruvate to lactate in a glycogen-containing subline of Ehrlich ascites tumour cells. The possible pathways of utilization of glucose-6-phosphate (G-6-P) produced from glycogen breakdown have been investigated in a glycogen-containing subline of Ehrlich ascites tumour cells. Addition of either mitochondrial inhibitors or pyruvate to ascites cells metabolizing endogenous substrates enhances the rate of lactate production. However, only in the former condition such effect is abolished by iodoacetate (IAA). In pyruvate-supplemented cells mitochondrial inhibitors cause a further increase in lactate production which becomes insensitive to IAA when the cells are depleted of endogenous substrates. Measurements of the glycogen content show that either in the presence of mitochondrial inhibitors or pyruvate there is a stimulation of glycogenolysis. Significant changes (about 10--20 fold increase) of the G-6-P level are observed only in the presence of both mitochondrial inhibitors and IAA, irrespective of pyruvate addition. However, with pyruvate the accumulation of G-6-P becomes lower if the cells are starved. The results obtained indicate that in our conditions G-6-P which is produced during glycogenolysis may be oxidized either through the Embden-Meyerhof pathway or the phosphogluconate pathway. Indeed, whereas mitochondrial inhibitors promote the utilization of this metabolite through the first route by enhancing the activity of phosphofructokinase, added pyruvate favours the other route by lowering the cytosolic NADPH/NADP+ ratio.


The effect of iron, tin, aluminium, and chromium on fading, discoloration, and precipitation in berry and red beet juices. The effect of iron(II), tin(II), aluminium(III), and chromium(III) on the properties of red whortleberry, blackcurrant, and red beet juices was followed during storage for 10 months at 5 degrees C. The colour and pH changes were studied, and the precipitates formed were weighed and their metal contents assayed. Of the metals tested, only tin caused bluish discoloration in the berry juices. In the case of iron, aluminium, and chromium the low pH prevented this type of discoloration. In berry juices, some increases in colour intensity took place with the lowering of pH value, whereas in red beet juice the opposite change occurred. The colour changes due to storage appear to take place irrespective of the metals. Precipitation is enhanced in red whortleberry juice only by tin, and in blackcurrant juice by tin and iron. In red beet juice, precipitation is increased by the lowering of pH resulting from metal salt addition. In general, increase in the amount of metal added increased the metal content of the precipitate. Iron showed the greatest tendency to become bound in the precipitate, particularly in blackcurrant and red beet juice. The suitabilities of the metals for canning purposes are considered. Chromium, in particular, has interesting possibilities in view of the low degree of colour change associated with it.


[On the enzymatic breakdown of tripolyphosphate and diphosphate in minced meat. V. Change in the diphosphatase activity of muscle post mortem (author's transl)]. The diphosphatase (DPase) activity of minced bovine muscle decreased during storage of the intact muscle post mortem (p.m.) but there was only little change after development of rigor mortis. The drop in pH p.m. seems to be not the only reason for the decrease in DPase activity. In the postrigor muscle the DPase activity, measured at pH greater than 6, increased during the breakdown of DP. The rise of activity was the slower the longer the muscle was stored. The result of a mathematical regression analysis, developed for the kinetic study of this anomaly in the breakdown of DP, indicates that a certain mechanism of activation of the initially inactive DPase in muscle exists.


[On the enzymatic breakdown of tripolyphosphate and diphosphate in minced meat. VI. Influence of pH on the tripolyphosphatase and diphosphatase activities in bovine muscle (author's transl)]. The pH optimum of the tripolyphosphatase activity of minced bovine muscle post rigor was 5.6. The pH optimum of the diphosphatase activity was in the range between pH 6.7 and 6.8. The prolonged influence of pH values around 7 caused an additional increase in the diphosphatase activity.


[Gluconic acid forming enzymes in Aspergillus niger (author's transl)]. At least three gluconic acid forming enzymes were identified in cell-free extracts of Aspergillus niger: glucose oxidase (EC 1.1.3.4), a glucose dehydrogenase (EC 1.1.99.10), and an enzyme or a mixture of enzymes catalyzing the cleavage of 6-phosphogluconate into gluconate and inorganic phosphate. 2,6-dichlorphenolindophenol was one of the hydrogen acceptors in vitro of the glucose dehydrogenase. Some properties of this enzyme (Km values, pH-dependence, substrate and hydrogen acceptor specificity), as determined in cell-free extracts, were found to be in good agreement with properties described in literature for a glucose dehydrogenase which has been purified from Aspergillus oryzae. The formation of Pi from 6-phosphogluconate and other phosphate esters was found to have an optimum between pH 7 and 8 , and another below pH 4. This suggests that it is catalyzed by an alkaline and an acid phosphomonoesterase (EC 3.1.3.1, 3.1.3.2), both enzymes exhibiting only low substrate specificity. The influence of extraction and assay buffers on the activity of gluconate forming enzymes was investigated. Loss of activity during preparation of cell-free extracts, as calculated from loss of activity storage of cell-free extracts at 4 degrees C, was found to be lower than 4%. Purified glucose oxidase added before homogenization was found in the extract almost quantitatively.


The fermentative production of acetone-butanol by Clostridium acetobutylicum. Fourteen different media were used in the fermentative production of acetone-butanol. The highest total yields were achieved in medium I. Potato starch and soluble starch were suitable as carbon sources. The best concentrations of potato starch and soluble starch were 500.0 and 10.0 g/l, respectively. Peptone was the most favourable nitrogen source. The best concentration of peptone was 4.0 g/l. Calcium carbonate in 3.6 g/l acted as buffering agent in the fermentation process. The best initial pH value of the fermentation medium was 6.0. The optimum temperature was 32--33degreesC. The fermentation process required 120 h to obtain maximum yields of acetone-butanol.