Growth kinetics and cellulase biosynthesis in the continuous culture of Trichoderma viride. Continuous culture studies have been carried out growing Trichoderma viride QM 9123 in a 10 liter stirred fermentor on a medium containing commercial glucose as the carbon source. Experiments were carried out at 30 degrees C and at three controlled pH values of 2.5, 3.0, and 4.0 over a range of dilution rates from 0.01 to 0.11 hr-1. Steady-state values of cell, glucose, and cellulase concentration oxygen tension, and outlet gas oxygen partial pressure were recorded. Values of maximum specific growth rate, endogenous metabolism coefficient, Michaelis-Menten coefficient, yield and maintenance coefficient for glucose were derived and correlated the effect of the hydrogen ion concentration. Specific oxygen uptake rates were correlated with specific growth rates and absorption coefficients were shown to be a function of dilution rate independent of pH. Some data on cellulase biosynthesis were examined and correlated in terms of a maturation time model.


[Tyrosine hydroxylase activation upon electric stimulation of isolated hypothalamic nerve endings in rats]. The effect of electrical stimulation on the membrane-bound tyrosine hydroxylasectivity of the rat hypothalamus synaptosomes was studied. The electrical stimulation caused an elevation of O2 consumption and the elevation of glycolysis indicating synaptosome excitation. The membrane-bound tyrosine hydroxylase activity increased under these conditions. The KM value for tyrosine decreased from 0.091 to 0.026 mM. Noradrenaline inhibition of the enzymatic activity diminished. It is assumed that the effect of depolarization on the catecholamine synthesis velocity in the nerve endings involves tyrosine hydroxylase modification.


[Regeneration of mammalial plantar skin]. Two sole tubers of rat's hind leg were excised together with the surrounding skin and one of the hind tubers of hind and fore legs in hedgehogs were excised without the surrounding skin. During healing the skin wounds in rats and hedgehogs new skin proved to form with the papillary layer typical of the sole skin. In hedgehogs the new skin covered the regenerated sole tuber; in rats the sole tubers failed to regenerate.


[Ammonia formation in the brain during dying and in the recovery period following resuscitation]. Dynamics of some nitrogen metabolism indices in the brain of dogs during dying and post-resuscitation period was studied in experiments on dogs. Glutamine proved to serve as the main source of ammonium hydrate in the brain during dying and clinical death. In the reconstruction period after revival of the organism glutamine was converted into ammonium eliminator, and the main sources of ammoniogenesis were labile amide protein groups.


[Demethylation of methindione].

[Demethylation of methindione]. Methindion demethylation was shown to occur in rats. This process proceeds with the participation of NADPH-dependent transport system of microsomal electrons. In experiments in vivo methindion demethylation coursed at a high rate and was accompanied by a partial loss of its anticonvulsive effects.


[Inactivation of stem cells by allogenic lymphocytes: competition between T1- and T2-subpopulations]. Transplantation of the bone marrow cells with allogeneic T-lymphocytes to the irradiated hosts was accompanied by inactivation of the stem elements of the graft. The lymph node cells of T-mice (those deprived of B cells) were more active than the spleen cells of these mice. The stem cells inactivation was weakly expressed or absent in case of a combined acti-n of T-cells from the lymph nodes and the spleen.


Demonstration of hemopoietic stem cells in the peripheral blood of baboons by cross circulation. Baboons were given 1200 R total body irradiation from two opposing 60Co sources. Three animals were given supportive therapy only and died, as expected, within 8 days of irradiation with profound marrow hypoplasia. Five baboons were cross-circulated with unirradiated partners and died within 14 days with evidence suggestive of graft-versus-host disease. Their marrows were repopulated with hemopoietic precursor cells, and three of the five had rises in peripheral white blood cell counts to more than 1500/cu mm before death. These results are compatible with the presence of hemopoietic stem cells in the peripheral blood of a nonhuman primate, the baboon.


Alterations in brain 5-hydroxytryptamine metabolism during the 'withdrawal' phase after chronic treatment with diazepam and bromazepam. 1 Daily administration of diazepam or bromazepam (10 mg/kg) for 22 days significantly increased the activity of mid-brain tryptophan hydroxylase by 36% and 39%, respectively. The concentration of tryptophan was also enhanced in the mid-brain region of rats subjected to benzodiazepine treatment.2 Chronic therapy with either of the two anti-anxiety agents enhanced the endogenous levels of 5-hydroxytryptamine and 5-hydroxyindoleacetic acid in cerebral cortex, hypothalamus, pons-medulla, mid-brain and striatum.3 Whereas diazepam treatment decreased (13%) the activity of monoamine oxidase in mid-brain, bromazepam failed to exert any effect, suggesting that the observed elevation in 5-hydroxy-indoleacetic acid levels is not associated with enhanced deamination of 5-hydroxytryptamine.4 Discontinuation of treatment for 48 h significantly decreased the activity of mid-brain tryptophan hydroxylase to levels that were significantly lower than those seen for benzodiazepine-treated and normal rats. The concentrations of mid-brain tryptophan and 5-hydroxytryptamine were also reduced in various brain regions examined.5 Withdrawal from diazepam or bromazepam therapy further augmented the levels of brain 5-hydroxyindoleacetic acid.6 The results demonstrate that the depressant effects on behaviour of these agents are accompanied by increased metabolism of 5-hydroxytryptamine in the brain. Withdrawal from these minor tranquillizers, on the other hand, reduces the synthesis of this indoleamine.


Responses of the cardiovascular system of the rat to alpha-and beta-adrenoceptor agonists. 1 The effects of intravenously infused phenylephrine and isoprenaline upon the cardiovascular system of the rat anaesthetized with pentobarbitone, have been investigated.2 Phenylephrine produces a dose-dependent rise in mean arterial blood pressure (MABP) that is due mainly to an increase in total peripheral vascular resistance (TPR), though at all doses tested cardiac output was invariably raised.3 The increase in cardiac output was due in each instance to an increase in stroke volume, heart rate being unchanged. This increase in cardiac output is probably brought about by effects of phenylephrine on the capacitance vessels rather than by an effect on the heart.4 Evidence is presented to show that the effects of phenylephrine are mediated largely by alpha-adrenoceptors, but that beta-adrenoceptors which affect TPR are also stimulated by the amine.5 Isoprenaline produces a dose-dependent fall in MABP that is due entirely to a fall in TPR since the cardiac output increases.6 Unlike phenylephrine, the increase in cardiac output obtained with isoprenaline was achieved by an increase in heart rate while stroke volume remained close to control values. It is contended that the augmented venous return required for the elevated cardiac output results in this case mainly from the isoprenaline-induced fall in TPR which enhances transfer of blood from arteries to the veins.7 Evidence is presented to show that the effects of isoprenaline are mediated mainly by beta-adrenoceptors.8 Under the present experimental conditions the adrenoceptor-mediated cardiovascular changes are little modified reflexly by the arterial baroreceptors.


Responses of the cardiovascular system of the rat to noradrenaline infusions and their modification by adrenoceptor blocking agents. 1 The effects of noradrenaline upon the cardiovascular system of the rat, anaesthetized with pentobarbitone, have been investigated.2 Noradrenaline produces a dose-dependent increase in mean arterial blood pressure (MABP) which is due entirely to an increase in cardiac output; total peripheral vascular resistance (TPR) remains unchanged.3 Following beta-adrenoceptor blockade the pressor response to infused noradrenaline is enhanced and is now due mainly to an increase in TPR; the increment in cardiac output is reduced.4 After alpha-adrenoceptor blockade the pressor response is greatly reduced; the residual increase in MABP is due solely to an increase in cardiac output.5 After ganglion blockade resting cardiac output and TPR both fall, resulting in a reduction in MABP. The pressor response to noradrenaline is enhanced and is now due to increases in both TPR and in cardiac output.6 The cardiovascular response of the anaesthetized rat to noradrenaline can be explained in terms of classical alpha- and beta-adrenoceptor stimulation by the amine; the unusual form of the response may be due to an effective predominance of beta-adrenoceptor-mediated effects in this species.7 It is suggested that the failure of exogenous noradrenaline to produce a rise in TPR results from a balance between the alpha-adrenoceptor-mediated increase and beta-adrenoceptor-mediated decrease in this variable. However, this proposed balance is lost if resting vasoconstrictor tone is reduced by ganglion blockade.


Development of nicotinic responses in the rat adrenal medulla and long-term effects of neonatal nicotine administration. 1. The development of nicotinic responses in the rat adrenal medulla was examined at various ages from 1 to 50 days of age by testing the ability of nicotine (10 mg/kg, s.c.) to deplete catecholamines and induce tyrosine hydroxylase. 2. Catecholamines were depleted 25% 3 h after injection of nicotine at all ages tested, but the degree of tyrosine hydroxylase induction 24 h after nicotine increased with age. 3. These data indicate that functional nicotinic receptors are present in the neonatal adrenal medulla before the development of functional splanchnic innervation, but that the development of the ability to induce tyrosine hydroxylase is not coupled directly to the development of secretory mechanisms. 4. The long-term effects of a single dose of nicotine (10 mg/kg, s.c.) administered to one day old rats were also examined. 5. After the short-term catecholamine depletion caused by nicotine, there were persistent elevations of catecholamines and tyrosine hydroxylase until 23 days of age; however, dopamine beta-hydroxylase remained elevated into young adulthood. 6. These data indicate that neonatal nicotine administration can produce long-term changes in adrenal catecholamine biosynthetic enzymes.


Central mechanism of vasopressin-induced changes in antidiuretic hormone release. 1. Intracerebroventricularly (i.c.v.) administered vasopressin (0.001-1.0 u) in dogs anaesthetized with chloralose produced adose-dependent increase in urine flow with a concomitant decrease in the levels of antidiuretic hormone (ADH) in jugular vein blood. 2. Higher doses of vasopressin (1.5-2.0 u, i.c.v) on the other hand had an antidiuretic effect and produced an increase in blood ADH level. 3. Pretreatment (i.c.v.) with a beta-adrenoceptor antagonist completely blocked the diuretic response of low doses of vasopressin (i.c.v.) but  did not influence the antidiuretic response obtained with high doses. 4. Repeated administration of vasopressin (1.0 u, i.c.v.) induced tachyphylaxis; central catecholamine depletion with tetrabenazine significantly inhibited the vasopressin-induced diuretic response. 5. It is concluded that intracerebroventricular vasopressin-induced changes in ADH secretion are mediated through the release of catecholamines in the central nervous system.


Selectivity of blocking agents for pre-and postsynaptic alpha-adrenoceptors. 1. Low frequency (0.1 Hz) electrical stimulation of the rat isolated vas deferens produced regular contractions that were inhibited by low concentrations of clonidine. 2. The inhibition of the vas deferens produced by clonidine was presynaptic in origin and involved alpha-adrenoceptors. 3. Presynaptic alpha-adrenoceptor antagonist activity was assessed by studying the effects of increasing concentrations of the antagonists on cumulative clonidine dose-response curves on the stimulated vas deferens. 4. Postsynaptic alpha-adrenoceptor antagonist activity was assessed by comparison of control cumulative noradrenaline dose-response curves with those in the presence of increasing concentrations of antagonists in the rat anococcygeus muscle. 5. The results indicate that yohimbine and phentolamine are more potent in blocking presynaptic than postsynaptic alpha-adrenoceptors. Phenoxybenzamine and prazosin block postsynaptic alpha-adrenoceptors preferentially. 6. The findings support the view that presynaptic and postsynaptic alpha-adrenoceptors differ in their sensitivity to alpha-adrenoceptor antagonists.


The use of functional antagonism to determine whether beta-adrenoceptor agonists must have a lower efficacy than isoprenaline to be trachea-atria selective in vitro in guinea-pigs. 1 The relative efficacies of three trachea-atria selective beta-adrenoceptor agonists, fenoterol, Me 506 and Me 454, compared to isoprenaline, were determined on both trachea and atria of guinea-pigs. 2 On tracheal preparations the beta-adrenoceptor agonists were used as functional antagonists of carbachol and a comparison of the maximum shifts in the carbachol concentration-response line produced by each of the beta-adrenoceptor agonists provided a comparison of their efficacies. 3 On atrial preparations carbachol was used as a functional antagonist of the beta-adrenoceptor agonists and comparison of the maximum responses to the beta-adrenoceptor agonists in the presence of carbachol provided a comparison of their efficacies. 4 On trachea and atria the order of efficacy of the compounds was Me454 greater than Me506 greater than or equal to isoprenaline=fenoterol. 5. The results indicated that high efficacy in a non-catechol beta-adrenoceptor agonist is possible provided there is a favourable N-substituent group. 6 Since Me 454, Me 506 and fenoterol, which are trachea-atria selective, have effficacies equal to or greater than that of isoprenaline, which is non-selective, it is concluded that low efficacy in a compound is not essential for it to show trachea-atria selectivity in vitro in guinea-pigs.


Subcellular distribution of glutamyltransferase activities in embryonic cerebral hemispheres. Glutamyltransferase (GT) activities were examined in cell groups from embryonic cerebral hemispheres. During normal development, GT activities were highest in a mixed population of small neurons and non-neuronal cells (small cell group). In culture, in response to hydrocortisone, activities exceeded normal levels only in this small cell group. In view of these findings, the small cell population was used to study the subcellular distribution of the enzyme. At the subcellular level, GT activities in the small cell group were distributed differentially but increased generally during normal development. In vitro, hydrocortisone promoted a precocious increase in GT activity, under experimental conditions regarded as optimum, only in the subcellular fraction characterized by synaptic endings.


Mnoaminergic reinnervation of the transected spinal cord by homologous fetal brain grafts. It was shown that immature noradrenaline (NA) containing cells from locus coeruleus and 5-hydroxytryptamine (5-HT) containing cells from the raphé nuclei could survive homologous transplantation to adult spinal cords that were adrenergically denervated by a transverse lesion. Fully viable transplants were found at all postoperative time studied (0.5-4 months) and both NA and 5-HT cell bodies were found to produce a network of nerve terminals in the gray matter and axons in the white matter that reached cranially and caudally at least 10 mm from the cell bodies. The nerve fibers had a normal varicose appearance. It was concluded that NA and 5-HT axons can grow in adult lesioned white matter.


Determination of the preferred tautomeric form histamine by 13C nmr spectroscopy. The pH-dependent 13C chemical shifts for histamine indicate an approximate 4: 1 preference for the N-H tautomer of the imidazole ring, similar to that previously deduced for L-histidine. It is concluded that the 13C chemical shift method is a complimentary technique to the method of determining tautomer preference from pK values. Factors determining the tautomer preference in histamine and L-histidine are discussed.


Effect of metabolites on epsilon-N-hydroxylysine formation in cell-free extracts of Aerobacter aerogenes 62-1. The conversion of L-lysine to its corresponding epsilon-N-hydroxy derivative has been achieved for the first time by cell-free extracts of Aerobacter aerogenes 62-1. Partial fractionation by differential centrifugation (at 12 000 X g) revealed that both supernatant and pellet are essential for maximum enzymatic activity. The omega-N-hydroxylase (EC 1.14.99) was found to function optimally at pH 7-7.5 and exhibited an apparent Km of about 75 muM for L-lysine. L(+)-Lactate or DL-lactate and pyruvate greatly stimulate the omega-N-hydroxylase activity. The system is strongly inhibited by arsenite and sulfite.


Studies related to antitumor antibiotics. Part IX. Reactions of carzinophillin with DNA assayed by ethidium fluorescence. The reactions of the antitumor antibiotic carzinophillin (CZ) with native DNAs and synthetic polynucleotides have been examined by an ethidium fluorescence assay. CZ rapidly produces covalent linkage of the complementary strands of a variety of DNAs without activation. This process is accompanied by extensive alkylation, as detected by reduced fluorescence due to destruction of potential intercalation sites for ethidium. These processes which occur without loss of purine or pyrimidine bases show a preference for bonding to guanine groups (but not at the N-7 position). Examination of the reversibility of the cross-links suggests they involve one 'permanent' link to guanine and a second weaker linkage, possibly to a cytosine residue. Both cross-linking and alkylation show strong pH dependence and are favored at lower pH, suggesting that reactive sites on the antibiotic are basic. The addition of intercalating agents to DNA before treatment with CZ inhibits the cross-linking.


Characteristics of potassium ion transport in pea cotyledon mitochondria isolated by a zonal technique. Methodology was developed for measurement of K+ transport in pea cotyledon mitochondria isolated by zonal centrifugation. The valinomycin-mediated transport process required respiratory energy from Krebs cycle intermediates and was completely reversible in the absence of oxygen. The rate and extent of uptake were dependent on the presence of proton-conducting anions (with acetate plus phosphate being most effective), well-coupled mitochondria, and on the K+ concentration.


Lithium suppresses elevated behavioural activity and brain catecholamines in developing hyperthyroid rats. Neonatal hyperthyroidism in rats induced by daily administration of L-triiodothyronine for 30 days since birth resulted in a significant rise in mobility and the metabolism of brain norepinephrine and dopamine. Whereas administration of lithium carbonate (60 mg/kg ip) to normal rats for 6 days produced no effect on spontaneous locomotor activity and increased the synthesis and possibly release of this monoamine in several brain regions, this antimanic drug antagonized the L-triiodothyronine-stimulated increases in mobility as well as norepinephrine and dopamine metabolism of hypothalamus, midbrain, striatum, and cerebral cortex. Furthermore, lithium treatment restored the activity of catechol-O-methyl transferase (EC 2.1.1.6) in young hyperthyroid rats to virtually normal limits. Our data suggest that antiphasic or damping effects of lithium upon mood swings is controlled, at least in part, by catecholaminergic systems in the brain. The interrelationship between brain catecholamines and thyroid hormones seems to be important to our understanding of the action of lithium in affective illness.


The tricarboxylic and acid pathway in Desulfovibrio. Strains of two species of Desulfovibrio were examined for enzymes of the tricarboxylic acid cycle and related pathways. Pyruvate carboxylase (EC6.4.1.1) is present, and alpha-ketoglutarate is formed via the tricarboxylic acids. Glutamate, but not succinyl-CoA, arises from alpha-ketoglutarate. A pathway exists from pyruvate by malic enzyme (EC 1.1.1.39) activity to malate, then fumarate and succinate, again with no evidence of succinyl-CoA formation. The enzymes concerned with metabolism of these dicarboxylic acids show greater activity in the strains that can grow by fumarate dismutation. Glutamate (or glutamine), alpha-ketoglutarate, and yeast extract repress the enzymes that metabolize the tricarboxylic acids. There appears to be no glyoxylate cycle in Desulfovibrio vulgaris or D. desulfuricans.


A case of homosexuality treated by in vivo desensitization and assertive training. Sexual deviation is not a unitary condition, amenable to a single treatment approach. Deviant sexual arousal has been overemphasized while inadequate attention has been given to associated behavioural problems such as deficient heterosexual arousal, deficient heterosexual skills and gender role deviation. A client with homosexual arousal and requesting aversion therapy was treated successfully and rapidly using in vivo desensitization and assertive training. The treatment is described and the importance of the behavioural analysis in directing the course of therapy is stressed.


Metabolic response to total parenteral nutrition in cancer patients. In order to evaluate the metabolic response of nutritionally deprived cancer patients to parenteral nutrition, metabolic parameters including glucose turnover, oxidation, and Cori cycle activity were measured in eight patients before and during short-term (5 to 10 days) i.v. nutrition, with solutions containing amino acids and hypertonic glucose. Before parenteral nutrition, five patients had essentially normal glucose turnover, oxidation, and Cori cycle activity, whereas three patients had moderately increased glucose turnover and markedly increased Cori cycle activity. In response to parenteral nutrition, plasma glucose, insulin, and venous lactate concentration increased and free fatty acid decreased. The percentage of respiratory CO2 from glucose oxidation and the rate of oxidation increased. CO2 production increased, whereas O2 consumption was essentially unchanged. Respiratory quotient rose to greater than 1.0. Endogenous glucose production and high basal Cori cycle activity were decreased. Total parenteral nutrition was judged clinically beneficial in five patients, whereas one patient was unchanged. Deleterious responses, including moderate lactic acidemia, occurred in two of three patients with elevated basal Cori cycle activity.


A radioimmunoassay for 1-beta-D-arabinofuranosyluracil with reference to cross-reactivity of 1-beta-D-arabinofuranosylcytosine with an antibody. Antibodies directed against 1-beta-D-arabinofuranosyluracil have been produced in rabbits by immunization with a conjugate of 1-(5-O-succinyl-beta-D-arabinofuranosyl)uracil with human serum albumin. Two of four antibodies so obtained showed high specificity for 1-beta-D-arabinofuranosyluracil and allowed the development of a sensitive and reliable radioimmunoassay for this substrate. On the other hand, one antibody had a high affinity for 1-beta-D-arabinofuranosylcytosine. The binding of 1-beta-D-arabinofuranosylcytosine to this antibody was practically constant between pH 5.2 and 9.0, whereas 1-beta-D-arabinofuranosyluracil binding was affected drastically by pH. The pH-binding profile for 1-beta-D-arabinofuranosylcytosine and 1-beta-D-arabinofuranosyluracil was reminiscent of the specificity of ara-C-specific antibodies, which we previously obtained after immunization of rabbits with 1-(5-O-succinyl-beta-D-arabinofuranosyl)cytosine as a hapten.


Formation of methylhydrazine from acetaldehyde N-methyl-N-formylhydrazone, a component of Gyromitra esculenta. Gyromitrin, acetaldehyde N-methyl-N-formylhydrazone, is a toxin present in edible wild mushroom Gyromitra esculenta. At 37 degrees under different acidic conditions (pH 1 to 3), mimicking the milieu of human stomach, gyromitrin is converted to methylhydrazine, a known tumor inducer in mice and hamsters, through an intermediate, N-methyl-N-formylhydrazine. In addition, methylhydrazine is formed in the mouse stomach after p.o. administration of gyromitrin. These findings imply that consumption of G. esculenta could present a carcinogenic, as well as an acutely toxic, health hazard.


Weekly methotrexate-calcium leucovorin rescue: effect of alkalinization on nephrotoxicity; pharmacokinetics in the CNS; and use in CNS non-Hodgkin's lymphoma. Urinary alkalinization with oral sodium bicarbonate has decreased the incidence of acute nephrotoxicity and subsequent myelotoxicity in 18 adults receiving high-dose methotrexate with calcium leucovorin rescue (MTX-LCV) weekly in doses of 1-7.5 g/m2. Close monitoring of 24-hour serum creatinine and MTX levels can predict patients at risk for serious toxicity. By a prompt (24-36 hours) increase in the LCV dose rate, hematologic and biochemical evidence of myelosuppression has been prevented. Kinetic parameters in serum and lumbar cerebrospinal fluid (CSF) were studied in two patients following iv injection of 3 and 7.5 g/m2 respectively. Lumbar CSF MTX concentrations greater than 1 muM are achieved. The half-life of MTX in the CSF (11.95 hours) is twice as long as the serum half-life. In the presence of carcinomatous meningitis, further delay in the clearance of MTX from the CSF was seen. With weekly MTX-LCV, there have been four objective responses in six patients with non-Hodgkin's lymphoma in CNS relapse, including complete regression in two. It is suggested that therapeutic concentrations can be achieved in the central nervous system following MTX-LCV.


Binding of alkyl 1-thio-beta-D-galactopyranosides to beta-D-galactosidase from E. coli. The binding of a series of alkyl 1-thio-beta-D-galactopyranosides to beta-D-galactosidase from E. coli has been investigated. The inhibition constants were compared to the partition coefficients for the transfer of these substrate-analogues from water to 1-octanol. The relationships between the observed binding-constants and the partition coefficients indicate that part of the aglycon group binds to a hydrophobic area that is limited in relation to the length of hydrocarbon chain that can be accomodated. Outside this area, the hydrocarbon chain is only partially desolvated. The main driving-force  for binding of the aglycon group is the increase in entropy resulting from the return of water molecules from the more-organized layer around the solute molecule to the bulk-water phase.


Hypersensitivity reactions in the small intestine. III. The effects of allograft rejection and of graft-versus-host disease on epithelial cell kinetics. Allograft rejection of fetal intestine and graft-versus-host (GvH) disease have been used to study the effects of cell-mediated immune reactions on epithelial cell kinetics in mouse small intestine. In heterotopically transplanted isografts the cell production rate per crypt was similar to that in normally sited small intestine of the same age. However there was a six-fold increase in the rate of cell production per crypt during allograft rejection and a three-fold increase during GvH disease. Furthermore animals with GvH disease developed villous atrophy and had fewer crypts per villus that littermate controls. At the age of 19 days cell production per villus per hour was 97-5 in animals with GvH disease compared with 54-6 in controls. These results indicate that the pathological entity of 'partial villous atrophy' evolves in two distinct phases. Phase 1, a state of increased cell turnover with crypt hyperplasia but villi of normal length precedes the development of Phase 2, true villous atrophy.


The development of membrane specializations in the receptor-bipolar-horizontal cell synapse of the chick embryo retina. A freeze-fracture study. Retinae of chick embryos and chicks one to six weeks after hatching were examined in ultrathin sections and in freeze-etch specimens. The development of the synaptic contacts between receptor cells and bipolar cells starts at the end of the second week of incubation with the enclosure of the dendritic prolongations, invaginating receptor terminals accompanied by the appearance of electron dense material at the synaptic contact sites. Subsequently receptor terminals become filled with synaptic vesicles which surround the synaptic lamellae that appear on the 16th day of incubation. The application of the freeze-fracture technique demonstrates that the differentiation of the synaptic membranes continues into the first week post hatching. E-fracture faces of the presynaptic membranes are characterized by crater-like structures, called synaptopores. Their number is rather small during incubation and increases after hatching. In the P-fracture faces of the dendrites, which are enclosed by the receptor terminals, small particle aggregations appear on the 16th day of incubation. These small particle clusters increase by the apposition of further particles which become arranged in lines and bring out a lattice-like aspect. This arrangement of particles in the inner part of the cell membrane is the morphological expression of the maturation process. The significance of these aggregations as a postsynaptic receptor for neurotransmitters in excitatory cells is discussed.


Fine structure of the adhesive pads of Gonionemus vertens. The adhesive pads of Gonionemus vertens, located near the distal end of each tentacle, consist of a layer of columnar glandulomuscular cells surrounded by a collar of microfilament containing epithelial cells. The glandulomuscular cells contain dense secretory rods, microtubules, rough endoplasmic reticulum, Golgi elements and myonemes. Axons located between the basal portions of the glandulomuscular cells form synapses with the glandulomuscular cells. The roles of these various cell organelles in adhesion and detachment process are discussed.


Adduct formation between the carcinogen N-acetoxy-2-acetylaminofluorene and synthetic polydeoxyribonucleotides. The chemical carcinogen N-acetoxy-2-acetylaminofluorene (NA-AAF) was reacted with poly(dG-dC) - poly(dG-dC); poly dG - poly dC; poly(dA-dT) - poly (dA-dT); and poly dA - poly dT under a variety of conditions. Poly (dG-homo GC polymer and 10--20 more reactive the A + T polymers. Lowering the ionic strength increased the extent of reaction, while pH change (8.9 vs. 5.5) had only a small effect. If ionic strength was adjusted so that the two guanine-containing polymers showed equal thermal stability (as judged by Tm) then the alternating copolymer was 7 times as reactive as the homopolymer. In aggreement with previous investigators, the major product was found to be 8-(N-2-fluorenylacetamido) deoxyguanosine.


Effect of gastrin on the cell kinetics of rat gastric mucosa. The effects of gastrin on the cell kinetics of the gastric mucosa were studied in the rats. The labelling index by tritiated thymidine of the cell in the mucous neck zone began to rise 14 hours after a single dose of tetragastrin at 100 or 1,000 microgram/kg or synthetic human gastrin at 1,000 microgram/kg and reached the peak at 18 hours. With tetragastrin 100 microgram/kg administered subcutaneously together with a depot for 35 days, observations were made on the change in the turnover rate of the gastric epithelium by means of labelling index. The turnover rate was delayed in the surface epithelium and accelerated in the cells at the lower part of the foveolae in the gastrin-administered group. The cell suspension prepared from the rat gastric mucosa by trypsin digestion was cultivated with 5 per cent of CO2 in air for 48 hours. The group which was added with 10 microgram/ml of tetragastrin showed fluctuations in the labelling index almost similar to the groups administered 100 and 1,000 microgram/kg in vivo. It might be possible to support the hypothesis that gastrin not only has a trophic effect on the mucous neck zone but it also might be concerned with the turnover of the mature stage of gastric mucosa.


[Growth and sporulation of Entomophthora virulenta Hall and Dunn in discontinuous liquid culture]. Fermented cultures of Entomophthora virulenta showed an exponential phase with a specific growth rate of 0,14 h-1. The deceleration phase was 4 times longer than the exponential phase. Sexual sporulation occurred at the end of the deceleration phase. A technique of medium replacement demonstrated that any lack of nutritive balance induced the sporulation.


[Interaction of thymic cells and hemopoietic stem cells. Enhancing effect on irradiated thymus repopulation]. In irradiated mice engrafted with hemopoietic cells, the thymus is repopulated more rapidly by bone marrow-derived than by spleen-derived cells. Admixing thymic cells with the restorative suspension stimulates the thymic repopulation by spleen-derived cells whereas it has no effect on the repopulation by bone marrow-derived cells.


Clinical importance of lipase determination by the turbidimetric procedure as compared with determination by a chromatrographic procedure. The turbidimetric determination of serum lipase activity was compared with the chromatographic determination in three groups of patients, including patients affected by hepatic diseases, patients affected by pancreatic diseases and a control group. The two methods were also compared in the determination of lipase activity of human leucocytes in vitro. The results show that there is a good statistical correlation of lipase turbidimetrically determined at pH 9.15 and amylase in serum of normal individuals and in serum of patients with pancreatic diseases. There is no correlation between amylase and chromatographically determined lipase. The other types of lipase activity determined, i.e. turbidimetrically assayed at pH 5.5 and chromatographically assayed both at pH 5.5 and at pH 9.15, might be related to a different non-pancreatic enzymatic activity which is likely to lack diagnostic value. This suggests that methods of lipase determination based, for instance, on fatty acid liberation are of limited value in clinical studies on lipase.


[Amino acid-p-nitroanilide-splitting activities in human serum (author's transl)]. Proteolytic, arylamidase-like activities of human serum are determined by using a sensitive micromethod, based upon the Bratton-Marshall-reaction, and amino acid-p-nitroanilides as substrates. Besides the alanine-aminopeptidase and the oxytocinase, the dipeptide-aminopeptidase II, a neutral peptidase, and 6 other peptidases, not yet identified by us, are differentiated with the aid of 19 substrates, by adding 8 effectors, and by incubating the enzyme tests within the pH range 6.0 to 8.4.


A new variant of glucosephosphate isomerase deficiency: GPI-Kortrijk. A new case of glucosephosphate isomerase deficiency in a Belgian family is described. The activity of the enzyme was decreased to about 25-30% of the normal value. Characterization of the defect enzyme showed a decreased thermostability. Heating of the enzyme at 45 degrees C showed a loss of activity of 50% after 90 min. The pH-optimum and the KM-value for fructose 6-phosphate were normal. The electrophoretic pattern showed a faster migration. The variant described here differs from all known variants. Therefore we propose to give to this new variant the name GPI-Kortrijk.


Purification and properties of urinary alkaline ribonucleases from patients with nephrotic syndrome. Four urinary alkaline ribonucleases (RNase, EC 3.1.4.22) were purified from patients with nephrotic syndrome using phosphocellulose, DEAE-cellulose and Sephadex G-75 chromatographiy. These enzymes were designated as RNases 1--4, respectively, in order of elution on phosphocellulose chromatography. The respective purification of each fraction was 41-, 23-, 34- and 27-fold with a total recovery of 25%. The pH optima of these RNases were around 8.5 with Tris/HCl buffer and the reaction was activated by mono- and divalent cations, such as Na+, K+, Mg2+ and Ca2+, but inhibited by Fe2+, Cu2+ and Zn2+. EDTA had little effect on the velocity of reaction. The molecular weights of RNases 1--4 were estimated by gel filtration as 45 000, 32 000, 20 000, and 13 000, respectively. Each enzyme hydrolyzed pyrimidine nucleotides preferentially with higher affinity for poly(C) than poly (U) as determined with synthetic polymers and was free from other nucleolytic enzymes. The patients with renal disorders excreted one to four RNases in urine and the number of enzymes increased as the concentration of urinary protein increased. On the other hand, normal subjects excreted a single fraction essentially identical to RNase 1.


Properties of the thyroxine (T4) monodeiodinating system in rat liver homogenate. The monodeiodination of T4 in rat liver homogenate was studied. The two possible products of this reaction show very different properties. The metabolically very active T3 is rather stable in this system whereas the biological inactive reverse T3 (rT3) disappears very rapidly. This explains the low apparent rT3 production in the incubation mixture even under optimal conditions and the peculiar pH profile. The T4 to T3 converting reaction can be increased by the addition of mercaptoethanol to the medium; no further activation is possible by several cofactors tested. The apparent KM of the reaction is 1.6 x 10(-6) M. Reverse T3 does inhibit the reaction non competitive; Ki = 2 x 10 (10-8) M. Alpha-methyl-para-tyrosine, a specific inhibitor of tyrosine hydroxylase, has no significant effect on the reaction.


Conversion of T4 to T3 and rT3 and their cytoplasmic binding: pH dependency. The fate of T4 in target organs is conversion to T3 which is mainly responsible for the nuclear action of thyroid hormones. To further investigate this converting step the increase of T3 and its analogue rT3 in rat liver microsomes was measured by specific radioimmunoassays after adding T4 to the incubation medium. Maximal increase of T3 occurred at pH 6.0 and of rT3 at pH 9.5 indicating that two different enzymic systems may be involved in the deiodination of the tyrosyl or the phenolic ring of T4. An increase in the binding capacity of cytosol proteins for T4, T3 and rT3 with rising pH demonstrates that there is also a pH dependency of the cytoplasmic binding of these iodothyronines. These reaction conditions should not only be considered in in vitro experiments, but may also be of importance in modifying the availability of T3 for its nuclear receptors.


PZ-peptidase activity in human uterine cervix in pregnancy at term. PZ-peptidase (EC 3.4.--) was detected in human uterine cervix distributed in the soluble fraction after 100 000 x g centrifugation. Optimum pH for PZ-peptidase was observed to be pH 7.2--7.4, except for two of the preparations examined. PZ-peptidase activity was found to significantly increase in pregnancy at term as compared with that in a control group.


Diagnosis of Pompe's disease in cultured skin fibroblasts and primary amniotic fluid cells using 4-methylumbelliferyl-alpha-D-glucopyranoside as substrate. The possible interference of neutral alpha-D-glucosidase in the diagnosis of Pompe's disease using 4-methylumbelliferyl-alpha-D-glucopyranoside as substrate for the assay of acid alpha-D-glucosidase was investigated. The pH profile of alpha-D-glucosidase in control skin fibroblasts and amniotic fluid cells showed two peaks of activity. The shape of the pH profile depended upon whether or not the extract was added to the buffer before the substrate. If extract was added to the buffer before the substrate, a greater separation was obtained between the two peaks of activity. The neutral alpha-D-glucosidase activity could be totally removed by preliminary precipitation at pH 5.0. Following acid region whilst Pompe's cells had no activity enabling a clear distinction to be made between carriers and the disease state.


A new method for peptidase activity measurement in serum and tissues, using L-Leu-L-Leu as substrate. Peptidase-free L-amino-acid oxidase was purified from venom of Agkistrodon caliginosus and was used for the determination of serum peptidase (EC 3.4.1.-) activity with L-Leu-L-Leu as substrate. The peptidase activity in human serum rose remarkably in liver diseases, and had a significant correlation with serum transaminase activity. The peptidase activity in serum of rats treated with CCl4 was higher than that of normal rats. After Cellogel electrophoresis the zymogram of peptidase from human liver using di- or tripeptide as substrate appeared with three active bands; however, peptidase in serum of a patient with acute hepatitis showed only one active band.


Determination of the Tamm and Horsfall glycoprotein in human urine. A method for the routine determination of the Tamm and Horsfall glycoprotein in human urine is presented. The method is based on quantitative electroimmunoassay. It was demonstrated that the solubility of the Tamm and Horsfall glycoprotein was dependent on urinary ionic strength and pH. To minimize these variables all urines were buffered to pH 5.5 and then preincubated at 37 degrees C in 0.3% sodium dodecyl sulphate. This procedure solubilized and maintained the Tamm and Horsfall glycoprotein in solution. Excess sodium dodecyl sulphate was removed by gel filtration before the quantities of the Tamm and Horsfall glycoprotein were determined by electroimmunoassay. The method is simple, reproducible, has high precision and compares favourably with earlier published methods for the determinations of the Tamm and Horsfall glycoprotein.


Heterogeneity of erythrocyte pyruvate kinase deficiency and related metabolic disorders in patients with hematological diseases. In several patients suffering from congenital non-spherocytic hemolytic anemia or from malignant hemotological disorder associated with erythrocyte pyruvate kinase (PK) deficiency, a metabolic study has been carried out involving the following biochemical determinations: assay of red cell enzyme activities; estimation of glucose consumption; measurement of the rate of glycolytic intermediates; and, in some cases, enzyme purification and characterization of the PK variant. Metabolic equilibrium most probably does not depend on kinetic characteristics of PK molecules. Furthermore, the data obtained allow separation of cases with congenital non-spherocytic hemolytic anemia (hereditary defect) and acquired PK deficiencies.


Clonidine and the vasodilating beta blocker antihypertensive drug interaction. Because propranolol is contraindicated in some patients and since clonidine can decrease heart rate and renin release, clonidine was substituted for propranolol in 14 severely hypertensive minoxidil-treated outpatients. Clonidine induced weight loss which, since plasma concentrations were not suppressed, was not due to inhibition of release of antidiuretic hormone or renin. These endocrine interrelations were confirmed by later administration of clonidine to 4 of the subjects under controlled circumstances in our General Clinical Research Center. When substituted for propranolol, clonidine controlled blood pressure and heart rate in 8 of the 9 outpatients whose blood pressure had been previously well controlled. Clonidine and propranolol had additive antihypertensive effects in the other 5 patients. Thus, clonidine can substitute for propranolol or when added to the propranolol-vasodilator combination supply an additional blood pressure-lowering effects. This substitution or addition results in an increase in side effects. In addition, clonidine has a diuretic action under these circumstances by an unknown mechanism.


Plasmalemmal calcium in cardiac excitation-contraction coupling. 1. Mammalian heart muscle is extremely sensitive to the external calcium concentration. It reacts to alterations of the external calcium concentration with an immediate adaptation of contractile force. 2. In mammalian heart there is a network of large transverse tubules throughout the cell. These structures are regularly arranged at the level of the sarcomeric Z- and I-lines and increase the cell surface by a factor of ten. 3. Experimental evidence favours the assumption that the plasmalemma could be the site of a loosely bound superficial Ca fraction which becomes ionized upon depolarization and is again bound upon repolarization of the cardiac cell membrane. 4. A mechanism is discussed which bases the excitation-contraction coupling process on a physicochemical interaction of calcium with membrane phospholipids. The degree of interaction is thought to be governed by the transmembrane electric field, the induced dipole moment of membrane constituents, and proton activity within the membrane.


Metabolism of flurazepam by the small intestine. The metabolism of flurazepam-5-14C has been studied in man following catheterization of the portal and hepatic veins. Flurazepam was administered through a tube into the stomach in one patient and into the duodenum in two patients. Thin-layer chromatographs of portal vein blood showed that there was a rapid and early appearance of metabolites of flurazepam consistent with the metabolism of the flurazepam by the intestinal mucosa and at times when the concentrations in the hepatic vein and peripheral blood were very much lower than those in the portal vein. The major metabolites identified in portal vein blood were the mono- and didesetyl metabolies of flurazepam. Considerable hepatic uptake of flurazepam and its metabolites occurred, as evidenced by the lower concentrations of the parent compound and metabolites in the hepatic vein. Thus, "first-pass" metabolism of flurazepam following oral administration occurs in the small bowel mucosa of man as well as in the liver.


A study in mice of bromo and chloro acylurea analogues of the sedative-hypnotic bromureides. 1. A series of 1-(2-chloroacyl)ureas, related to the sedative-hypnotic drugs bromvaletone and carbromal, was synthesized and tested in mice to determine central depressant and acute toxic effects. Four 1-(2-bromoacyl)ureas and two 3-halo compounds were included for comparison. 2. Large variations in potency were seen between the compounds. Much of this can be ascribed to differences in lipophilicity. Among homologous 1-(2-chloroacyl)ureas, those with 6 acyl carbons had maximal potency. Among groups of structural isomers, the most potent were 2-halo, 3-alkyl substituted compounds. 3. The most potent compounds were also those with the largest ratios of hypnotic to lethal activity. 4. The variation in the onset and duration of action of these compounds enables a choice to be made for a compound with a particular set of characteristics.


The effect of chronic frusemide administration on intracellular potassium, sodium and pH of cardiac and skeletal muscle. 1. Chronic administration of frusemide in large doses of 4 mg day-1 kg-1 for 3 weeks caused a significant reduction of cell water in rabbit cardiac and skeletal muscle. Intracellular Na+ concentration, intracellular pH and extracellular space was unchanged in both tissues. Intracellular K+ concentration increased slightly in both cardiac and skeletal muscle. 2. It is concluded that frusemide does not reduce intracellular K+ concentration in cardiac or skeletal muscle of normal animals receiving a normal oral potassium intake.


Essential facets of radiological diagnosis of extremity trauma. Trauma to the extremities is sometimes dismissed as relatively unimportant in certain radiologic circles. In many instances, radiologic responsibility is denied and relegated to the orthopedist. Although the radiologic manifestations of much trauma to the extremities is clear cut and does not require sophisticated techniques or interpretation, there are many diagnoses which require innovative techniques and a knowledge of mechanisms of injury as well as the subtle oseous and soft tissue manifestations which may be confronted radiologically. The above factors will be stressed along with the need for the fundamental knowledge of radiologic anatomy which is required in order to appreciate some of the more subtle changes of extremity trauma.


Some factors affecting testosterone, dihydrotestosterone, 5 alpha-androstan-3 alpha,17 beta-diol and 5 alpha-androstan-3 beta,17 beta-diol secretion by invitro perfused rabbit testes. Intra-arterial infusion of testosterone-3H gave rise to tritiated dihydrotestosterone, 5 alpha-androstan-3 alpha,17 beta-diol and 5 alpha-androstan-3beta,17 beta-diol in spermatic venous effluent of the perfused rabbit testis-epididymis. Mass spectrometric measurements confirmed that these four androgens were present in spermatic venous effluent of the perfused rabbit testis-epididymis. Gas liquid chromatographic measurement showed that testosterone, dihydrotestosterone, 5 alpha-androstan-3 alpha,17 beta-diol and 5 alpha-androstan-3 beta,17 beta-diol were secreted in similar amounts by the in vitro perfused and in situ rabbit testis-epididymis results obtained by perfusing the testis minus the epididymis suggested that the bulk of these androgens originate from the catabolism of testosterone within the testis rather than the epididymis. Suprisingly, germinal epithelium destruction by heat failed to alter the testosterone, dihydrotestosterone and 5 alpha-androstan-3 alpha,17 beta-diol secretion by the in vitro perfused rabbit testis. In contrast, the secretion of 5 alpha-androstan-3 beta,17 beta-diol was significantly (P less than 0.05) reduced in the same cryptorchid compared to control testes.


Testicular androgen binding protein (ABP) - a parameter of Sertoli cell secretory function. Using ABP as an index of Sertoli cell secretory function, several important features of the Sertoli cell have emerged: 1. The stimulation of ABP production by FSH clearly points to the Sertoli cell as a target cell for FSH (3,4,9-16,21,24). 2. The dramatic effects of androgens on ABP production both in immature and mature rats also suggest that the Sertoli cell is a target cell for androgen (3,12,14,16,25). 3. The striking reduction in ABP production in the cryptorchid testis raises the question whether impairment of Sertoli cell function is the primary reason for the loss of germ cells that occurs in this condition (20). 4. Drugs like nitrofurazone or ethionine, or X-irradiation only slightly affect the secretory function of the Sertoli cells (ABP production), indicating that these treatments most probably have direct effects on the germ cells as well. Thus, measurement of ABP production rate is a very important tool in order to evaluate how hormones, drugs and physical injuries might affect the secretory function of the Sertoli cell. This test system might be of great use in order to study the physiology and hormonal regulation of the Sertoli cells. It might also be valuable in pharmacological and toxicological studies.


Regional assignment of seven genes on chromosome 1 of man by use of man-Chinese hamster somatic cell hybrids. I. Results obtained after hybridization of human cells carrying reciprocal translocations involving chromosome 1. Regional localization studies of genes coding for human PGD, PPH1, PGM1, UGPP, GuK1, Pep-C, and FH, which have been assigned to chromosome 1, were performed with man-Chinese hamster somatic cell hybrids, Informative hybrids that retained fragments of the human chromosome 1 were produced by fusion of hamster cells with human cells carrying reciprocal translocations involving chromosome 1. Analysis of the hybrids that retained one of the translocation chromosomes or de novo rearrangements involving the human 1 revealed the following gene positions: PGD and PPH1 in 1pter leads to 1p32, PGM1 in 1p32 leads to 1p22, UGPP and GuK1 in 1q21 leads to 1q42, FH in 1qter leads to 1q42, and Pep-C probably in 1q42.


Brain monoamines act through the prostaglandin release to influence the body temperature. In the present study, the thermal responses induced by intraventicular administration of pyrogen prostaglandin E1, the brain monoamines norepinephrine and serotonin, and the antipyretic sodium acetylsalicylate (aspirin) were measured in conscious rabbits to assess the possible involvement of these substances in fever production. The body temperatures, metabolic rate, respiratory evaporative heat loss and vasomotor activity in response to the administration of these drugs were measured. The results showed that sodium acetylsalicylate, an inhibitor of prostaglandin synthetase, antagonizes the norepinephrine induced fever but not the prostaglandin fever. The data also showed that the serotonin induced hypothermia was reversed by prostaglandin administration. Thus, the fact strongly suggest that the prostaglandin E1 serves as a fever-prducing mediator in the central nervous system. Also, the norepinephrine fever and serotonin hpyothermia, respectively, may be associated with an increase and a decrease in prostaglandin synthesis in the brain.


[Recurrent periarteritis nodosa with predominantly cerebral signs in children (author's transl)]. Periarteritis nodosa occurs also in children and has the same wide spectrum of signs and symptoms as in adults. In a 4 1/2 year-old girl the disease at first was characterised by cerebral, encephalitis-like symptoms, arterial hypertension, intestinal wall necrosis and, finally, pericardial tamponade as a result of rupture of an arteritic coronary artery aneurysm. An earlier attack had involved liver and skeletal muscle, with necrosis in the liver. Peculiar morphological features within the "classical" course of periarteritis nodosa are endarteritic changes of single retroperitoneal and coronary arteries.


Drug-induced cardiovascular diseases.

Drug-induced cardiovascular diseases. A wide variety of drugs may be associated with serious cardiovascular toxicity. Toxicity due to drugs primarily used for treating cardiovascular toxicity. Toxicity due to drugs primarily used for treating cardiac disorders is the most extensively documented, especially the arrhythmias due to digitalis glycosides. Various arrhythmias are also caused by toxic levels of many antiarrhythmic agents including quinidine, procainamide and phenytotin. Myocardial depression and heart failure are serious side-effects of beta-adrenoceptor blocking agents and myocardial ischaemia due to sympathominetic amines may result from both direct and indirect mechanisms. The many toxic reactions in the cardiovascular system due to non-cardiac drugs are less widely known and for the most part less clearly understood. Many remain controversial at the current time; for example, the diathesis toward thromboembolism in women taking oral contraceptives. Potential cardiac toxicity due to drugs used in the rapidly expanding sphere of anti-neoplastic chemotherapy is exemplified by the cardiomyopathy-like toxicities of doxorubicin and daunorubicin. Many of the psychotherapeutic drugs including phenothiazine antipsychotics and tricyclic antidepressants have arrhythmogenic potential.


[Telemetry of the tissue Ph value under the effect of local anesthetics. Preliminary report]. After discussing the problems involved in in vivo pH measurements, pH telemetry is presented as a new method. Long-term in vivo measurements of the pH are intended to be performed by means of a miniature transmitter implanted into the subcutaneous tissue of guinea pigs.


[The salivary fluoride level after administration of fluorides and fluoride complex salts]. Compounds of fluorine and Si or Fe are found in nature and are sometimes formed from F ions in the stomach. The chemistry of the release of resorbable F ions from such compounds in the intestinal tract is described. To demonstrate fluorine availability at the enamel surface daily profiles of fluorine concentration in the saliva of seven subjects after a single administration of a NaF and Na3FeF6 tablet are presented and their effect on the remineralization of the dental enamel described.


[Change in the mental contents in the paradoxical stage and in stage 2 under the effects of a benzodiazepine, flunitrazepam]. In some insomniacs under flunitrazepam treatment is noted on one hand a global increase of dream memories, and on the other hand an increase of dreams with unpleasant or anxious contents. The present investigation is intended first to test the hypothesis of a possible increase of mental contents in sleep outside the paradoxical phases, to account for the increase of dream memories without concomitant increase of paradoxical stage. Second it intends to investigate if the increase of unpleasant dreams may be found in the normal subject in laboratory.


Influence of temperature on the determination of enzyme activities in human serum. gamma-Glutamyl transferase. Optimum reaction conditions for determination of gamma-glutamyl transferase were studied at 25, 30 and 37 degrees C using a kinetic test and gamma-glutamyl-3-carboxy-4-nitranilide as substrate. There was no dependence on temperature of half saturation constants of gamma-glutamyl-3-carboxy-4-nitranilide. The corresponding constants for glycylglycine were influenced by temperature and the pH. The optimum showed a dependence upon temperature. In Arrhenius' plot, a deviation from straight line can be observed only above 35 degrees C. The influence of temperature on the determination of enzyme activities in human serum are discussed.


Guanosine triphosphate: 5-hydroxylysine phosphotransferase in rat kidney cortex. An enzyme which catalyzes the transfer of the gamma-phosphate from GTP onto 5-hydroxylysine was partially purified from rat kidney cortex by means of acid precipitation and DEAE-Sephadex A-50 column chromatography. The enzyme activity was assayed by measuring the transfer of [32P] from gamma-[32P]-GTP to materials not adsorbed by charcoal. This partially purified enzyme showed essentially no GTP phosphohydrolase activity and an optimal pH of 8.0. An apparent Km of about 23.8 mumol/1 was obtained with respect to 5-hydroxylysine. Mg2+ was required for the activity of this enzyme. Ethanolamine, L-lysine, L-ornithine and choline inhibited the enzyme but L-threonine, L-serine and hydroxy-L-proline did not. None of these compounds severed as substrate for this enzyme.


Isatin enzyme interactions. V. Activation of rat liver acid phosphatase. Influence of Isatin on rat tissue acid phosphatase has been studied. It has an organ-specific effect, the liver enzyme is activated, the brain enzyme is inhibited while those of kidney and intestine are not affected. Isatin activation of the liver enzyme is of mixed type and pH dependent. Rat liver enzyme appears to require intact amino and sulfhydryl groups for activity. Isatin seems to combine with the enzyme through the sulfhydryl group of the latter.


Effect of cofactor depletion on liver tyrosine aminotransferase expression. Hepatic tyrosine aminotransferase (L-tyrosine: 2-oxoglutarate aminotransferase, EC 2.6.1.5) was partially purified from pyridoxine depleted and control rats and subsequently resolved by electrophoresis on polyacrylamide gels. Enzyme activity was detected histochemically in situ on the gel. Six enzymatically active forms were detected. Cofactor depletion effected further resolution of the enzyme into seven active forms as revealed by the bifurcation of the major active peak.


Interactions of citrate synthases from osmoconforming and osmoregulating animals with salt: possible signs of molecular eco-adaptation? This study considers differential sensitivity of citrate synthase (citrate oxaloacetatelyase [CoA acetylating]) EC 4.1.3.7. from an osmoconforming animal (sea anemone) and an osmoregulating animal (the pig) to salt. Attention is drawn to the fact that the osmoconforming sea anemone is in essence a sessile creature while the pig is readily mobile and able to change its ionic environment at will. It had been shown earlier that citrate synthase from another osmoconformer (oyster) is also not sensitive to ionic strength while citrate synthase from osmoregulating white shrimp is sensitive to increasing levels of salt. However, these enzymes are characteristically regulated by ATP and alpha-ketoglutarate. Both forms of citrate synthase are denatured by 6 M guanidine hydrochloride and are aided by salt levels in their refolding but the rate and extent of refolding of the osmoconformer citrate synthase are greater than those of the osmoregulator citrate synthase. Catalytic activity of both forms of citrate synthase is inhibited by incubation in distilled water; osmoconformer citrate synthase was inhibited completely in 7 h while osmoregulator citrate synthase was inhibited only 60% in this time and 80% after 22 h in distilled water. The eco-adaptive and evolutionary implications of these findings are discussed.


A deoxyribonuclease from Chlamydomonas reinhardii. 1. Purification and properties. A deoxyribonuclease has been purified more than 2000-fold from the green algae, Chlamydomonas reinhardii. The enzyme is most active on denatured DNA. Optimum activity is at pH 8.5, in 80 mM Tris-HCl buffer and 2 mM CaCl2. Other divalent cations can replace Ca2+ with varying lower efficiency. EDTA and inorganic phosphate are strongly inhibitory, while ATP and high concentrations of 2-mercaptoethanol are slightly inhibitory. The molecular weight is approximately 35 000, the Stokes radius is 2.7 nm, and the sedimentation coefficient 2.8 S. It is a single polypeptide chain, and the frictional ratio of 1.27 suggests it is only slightly asymetrical. The isoelectric point is 9.5. This enzyme has been termed exonuclease 1.


Dihydroxyacetone reductase from Mucor javanicus. 1. Isolation and properties. An NADPH-dependent oxidoreductase has been extracted from the mycelium of the fungus Mucor Javanicus (Wehmer) and enriched 1000-fold with respect to the protein contained in the crude extract after centrifugation at 2600 X g. The molecular weight of the enzyme was estimated by gel filtration to be about 100 000; electrophoresis under dissociating conditions indicates four subunits of molecular weight about 28 000. Data on stability and activity of the enzyme as a function of pH and temperature are reported. From a kinetic study and product analysis of the reduction of the two enantiomeric trans-1-decalones and also from a kinetic study of the oxidation of the two diastereomeric pairs of trans-1-decalols it follows that the enzymes is an e-Si oxidoreductase (according to the nomenclature proposed by Dutler et al., Eur. J. Biochem. 22 [1971]203-212 and Prelog and Helmchen, Helv. Chim. Acta, 55 [1972] 2581-2598). This classification is amply confirmed by the kinetic behaviour of a large number of alicyclic substrates. Using (4-2HSi-labelled coenzyme to reduce (9S)-trans-1,4-decalindione, it was shown that the enzyme is HSi (= HS = HB)-stereospecific with respect to the coenzyme. It is demonstrated that the oxidoreductase from Mucor javanicus can be used for the preparation of optically pure chiral alcohols and ketones. In the following paper evidence is presented that the natural substrate of the enzyme is dihydroxyacetone.


On the structure of flavin-oxygen intermediates involved in enzymatic reactions. During the catalytic reactions of flavoprotein hydroxylases and bacterial luciferase, flavin peroxides are formed as intermediates [see Massey, V. and Hemmerich, P. (1976) in The Enzymes, 3rd edn (P. Boyer, ed.) pp. 421--505, Academic Press, New York]. These intermediates have been postulated to be C(4a) derivatives of the flavin coenzyme. To test this hypothesis, modified flavin coenzymes carrying an oxygen substituent at position C(4a) of the isoalloxazine ring were synthesized. They are tightly bound by the apoenzymes of D-amino acid oxidase, p-hydroxybenzoate hydroxylase and lactate oxidase; the resulting complexes show spectral properties closely similar to those of the transient oxygen adducts of the hydroxylases. The optical spectra of the lumiflavin model compounds were found to be highly dependent on the solvent environment and nature of the subsituents. Under appropriate conditions they simulate satisfactorily the spectra of the transient enzymatic oxygen adducts. The results support the proposal that the primary oxygen adducts formed with these flavoproteins on reaction of the reduced enzymes with oxygen are flavin C(4a) peroxides.


A phosphorus-magnetic-resonance study of the interaction of Mg2+ with adenyl-5'-yl imidodiphosphate. Binding sites of Mg2+ ion on the phosphate chain. The interaction of Mg2+ ions with adenyl-5'-yl imidodiphosphate, AMP-P(NH)P, has been studied at basic and acidic pH values by phosphorus magnetic resonance spectroscopy in aqueous solution. The results suggest that Mg2+ binds simultaneously to one (or both) of the two free oxygen atoms of the beta-phosphate moiety and to the nitrogen atom of the phosphate chain (P alpha-O-P beta-N-P gamma). The interaction arises from 1: 1 complexing of Mg2+ to AMP-P(NH)P. The mode of the Mg2+ binding on the phosphate chain remains the same at both basic and acidic pH values. As in the case of ATP and ADP, the association of Mg2+ reduces the pK by about 1.5 units. On the other hand phosphorus titration curves showed that when the phosphate chain does not possess the regular periodicity (O-P alpha-O-P beta-X-P gamma-O,X not equal to O) as in the case of ATP, protonation of the terminal phosphate group may induce a 31P chemical shift variation less important for this group than for the preceding one.


Nickel cytochrome c. Effect of protein moiety on the metal ion coordination. Nickel cytochrome c has been synthesized by the reaction of metal-free porphyrin cytochrome c with Ni(II) ions in 0.6 Mglycylglycine and 4 M KSCN. Electronic spectra and susceptibility measurement showed the nickel to be in a high-spin octahedral configuration exemplifying the strong influence of the protein moiety as a macrocyclic ligand on the coordination chemistry of the metal ion. Nickel cytochrome c has the same electrophoretic mobility, helicity and pK values of conformational transitions as the native enzyme. At high pH, the partially denatured nickel cytochrome c becomes dimeric. Nitric oxide reacts with nickel cytochrome c to form the nitrosyl derivative with (formula: see text). Reaction of NO with nickel protoporphyrin IX dimethyl ester in toluene, pyridine, or methylthioethanol produced no stable nitrosyl products, clearly demonstrating the effect of protein on metal ion ligation.


Anorchi.

Anorchi. Anorchia was diagnosed in 3 patients after a hormonal study entailing the basic determination of FSH, LH and testosterone by a radioimmunoassay technique and by later stimulation with HCG. 2,000 IU are administered during 3 consecutive days with a new testosterone determination 24 and 72 h after the last administration. If the result is negative, the test is repeated but the HCG dose is doubled. A new negative response confirms the diagnosis of anorchia. If the results are positive a spermatic phlebography allows localization of the testicles or the remains of Wolffian origin in order to simplify surgery.


Regional changes in the activities of aminergic biosynthetic enzymes in the brains of hypertensive rats. The activities of monoamine biosynthetic enzymes were measured in brain regions of several hypertensive rat models at various ages. The types of hypertensive rats were the spontaneously hypertensive rat (SHR) and a stroke-prone substrain of the SHR as well as DOCA-salt and renal hypertensive rats. The genetically hypertensive rats had significantly elevated blood pressures as compared to the Wistar-Kyoto control rat after 5 weeks of age. During the early development of hypertension in the SHR, the activities of tyrosine hydroxylase in the hypothalamus and corpus striatum and of dopamine-beta-hydroxylase in the hypothalamus and pons-medulla were significantly higher than in the control rats. Tryptophan-hydroxylase was also elevated in the hypothalamus in SHR. From 3 to 8 weeks of age there appeared to be a significant correlation between hypothalamic dopamine-beta-hydroxylase activity and blood pressure in the hypertensive rats. In contrast, the activities of tyrosine hydroxylase and dopamine-beta-hydroxylase were slightly decreased in the DOCA-salt and renal hypertensive rats. It is suggested that noradrenergic or adrenergic neurons in the hypothalamus may participate in the initiation of elevated blood pressure in the genetic, but not in the DOCA-salt or renal hypertensive rats.


Some cardiovascular effects of ST-91 and clonidine. St-91, 2(2,6-diethylphenylamino)-2-imidazoline, is a clonidine derivative which does not penetrate the blood-brain barrier. In spontaneously hypertensive (SH) rats is acutely increased arterial pressure and reduced heart rate while at 8 to 12 h after oral administration, it slightly lowered arterial pressure. In contrast, clonidine had acute antihypertensive activity at all doses used. By intracerebroventricular administration to SH rats, both drugs (St-91 and clonidine) reduced arterial pressure and heart rate; in this respect, clonidine was more potent then St-91. Cardiac acceleration induced by low frequency electrical stimulation of right cardiac sympathetic nerves in anesthetized and vagotomized dogs was reduced by St-91 at the same doses by clonidine. Phenoxybenzamine, phentolamine and desipramine antagonized the inhibitory effects of St-91 on electrically induced cardiac acceleration. It was concluded that St-91, like clonidine, stimulates inhibitory alpha-adrenergic receptors at the sympathetic nerve endings but, unlike clonidine, is substantially devoid of acute antihypertensive activity. This suggests that stimulation of peripheral presynaptic inhibitory alpha-adrenergic receptors is not likely to represent the sole mechanism of antihypertensive action of clonidine.


Specific alpha-adrenoceptor blocking effect of droperidol on isolated smooth muscles. The present study was conducted so as to obtain more insight into the controversies concerning the alpha-adrenoceptor blocking properties of droperidol, a short-acting neuroleptic agent used in neuroleptanalgesia. The effect of droperidol on the vasoconstriction induced by norepinephrine, sympathetic nerve stimulation, histamine and potassium ions was studied on isolated, perfused ear arteries; its effect on norepinephrine-induced contraction was studied on isolated aorta, spleen and vas deferens. In addition, the onset and duration of action of droperidol was studied. Low doses of droperidol inhibit the vasoconstriction induced by norepinephrine and sympathetic nerve stimulation in the ear artery of the rabbit (3.3 X 10(-9) M and 1.3 X 10(-8) M respectively). At similar low doses, droperidol inhibits norepinephrine-induced contractions in the other tissues studied and has a potency comparable to that of phentolamine; its action is rapid in onset and of short duration. High doses of droperidol (10(-6) M) also inhibit the vasoconstriction of the ear artery induced by histamine and by potassium ions. These findings indicate that a low doses, droperidol has specific and competitive alpha-adrenoceptor blocking effects.


Withdrawal syndrome upon cessation of chronic clonidine treatment in rats. Clinical reports indicate that cessation of treatment with the antihypertensive agent clonidine is associated with a withdrawal syndrome which may include a hypertensive overshoot of critical proportions. We have attempted to produce an animal model of this syndrome in rats. Rats were treated with clonidine in the drinking water (5 microgram/ml; total dose 300-500 microgram/kg/day) which produced a significant (approx. 20%) decrease in heart rate and blood pressure. Within 24 h of cessation of treatment a significantly greater (approximately 100 beats/min) heart rate was seen in treated animals than in control animals when measurements were made in conscious animals. No hypertensive overshoot was observed. Cessation of treatment was associated with an increase in sympatho-adrenal tone as shown by a trans-synaptic induction of adrenal tyrosine hydroxylase activity. Adrenal denervation prevented the rise in adrenal tyrosine hydroxylase seen after cessation of treatment. Administration of clonidine to pregnant rats (10th day until term) did not alter the development of adrenal tyrosine hydroxylase in the offspring. The data indicate that a withdrawal syndrome is produced upon cessation of chronic clonidine treatment.


[Effect of various analeptics on the outcome of acute microwave lesion in mice]. The survival of albino mice irradiated by microwaves till the terminal state (wave length of 12.5 cm, intensity-62 +/- 5 microvat, for 14-16 minutes), given directly after irradiation diethylamide of nicotinic acid (cordiamine) in a dose of 50 mg/kg intraperitoneally and strychnine nitrate in a dose of 1 mg/kg, subcutaneously, i. e. nearly 1.5 times as much as received by controls, was studied. The application of caffeine sodium benzoate, camphor, metrasol, lobeline hydrochloride and cytisine, employed in different doses, proved to be little effective.


[Effect of corticotropin on functional and metabolic processes in muscles]. Changes of excitability, contractility, temperature, activity of oxydation-reduction enzymes, pyridine nucleotides, and of free fatty acids were studied in m. m. gastrocnemii of rabbits and rats during activity, after administration of 1 unit per 100 g of corticotropin (ACTH). Within 30 min after administration, the ACTH did not alter the excitability of a neural-muscular system but increased its efficiency by means of stimulation of the free fatty acids usage. Besides, the ACTH elicits no regular changes of the oxydation--reduction enzymes activity during a short-lasting muscular activity. Its regulating effect on the metabolic processes in muscles is realised at the level of anaerobic processes.


[Relationship between the pain-relieving action of narcotic analgesics and their effect on respiration]. Experiments with rabbits (30) and albino rats (110) demonstrated that morphine (1 mg/kg), promedol (trimeperidine) (2 mg/kg) and phentanyl (0.02 mg/kg), while raising by 21-24 per cent of the algesia threshold, produced an analgesic effect differeing in its duration (morphine-130 min, trimeperidine-70 min, phentanyl-17 min). This is attended by changes in respiration (greater on introduction of phentanyl, and lesser, following administration of morphine) and by shifts in the functional state of the tissues (greater on introduction of trimeperidine and lesser after aministration of morphine).


Nucleolar and functional characterization of lymphocytes following cyclophosphamide treatment. Profound lymphocyte depletion occurs in thymus, lymph nodes and spleens of normal and thymectomized mice early after a single high sublethal dose of cyclophosphamide. Among individual lymphocytes characterized by the different types of nucleolus, the "non-activable" lymphocytes with micronucleoli are affected most markedly by CY, whereas the proportion of the "active" lymphocytes is increased (up to 70% in the spleens). During the period of regeneration lymphocytes with micronucleoli increase rapidly, the increment thereof is very high on day 14 in the spleens of all mice, and still higher in the blood and lymph nodes of thymectomized animals. During the period of lymphocytopenia, in spite of the increased proportion of the "active" lymphocytes, the ability of residual cells of elicit GVH reactions and to incorporate 14C-uridine decreases. In contrast to changes in the early period, the recovery of the "active" lymphocytes and GVH reactivity, which is still incomplete on day 14, depends on the presence of an intact thymus.


Evidence for improved cardiac performance after beta-blockade in patients with coronary artery disease. The study was undertaken to investigate the acute haemodynamic effects of bunitrolol (0-2-hydroxy-3-(tert.butylamino)-propoxy)-bity. Right and left heart catheterization was performed in eleven patients with documented coronary artery disease. After bunitrolol (10 mg i.v.), there was a statistically significant decrease in left ventricular and aortic systolic pressures left ventricular end-diastolic pressure, aortic diastolic and mean pressures, pressure-rate product and compliance index (delta P/delta V).  Left ventricular dp/dt, left ventricular dp/dt over isovolumic pressure, systemic resistance and heart rate tended to decrease, stroke volume and left ventricular stroke work index tended to increase, without statistical significance. Cardiac index showed individual variations, the mean values for the group being unchanged. Correlation of left ventricular end-diastolic pressure and left ventricular stroke work index showed a shift toward improved ventricular function curve in most cases, deterioration in no instance. Supine exercise was performed in ten patients. Angina occurred in nine patients; in five only before and in four before and after beta-blockade. Post-drug exercise heart rate, pressure-rate product and left ventricular end-diastolic pressure were significantly lower, the latter also in the four patients who still presented exercise angina. It is concluded that certain beta-blockers can improve cardiac performance at rest and during exercise in patients with coronary artery disease. This is explainable on the basis of a more favourable balance between oxygen supply and demand, together with a less marked negative inotropic effect due to the partial agonist activity of the agent used in the study.


The use of flurazepam (dalmane) as a substitute for barbiturates and methaqualone/diphenhydramine (mandrax) in general practice. A twelve-week study involving fifty-three patients is described as taking place in a practice with a higher than average geriatric population. The purpose of the study was to substitute flurazepam for habitually used barbiturates or methaqualone/diphenhydramine. Of the original fifty-three patients admitted to the study, fifty-one completed; the two drop-outs resulting from concomitant physical illness. Eighty-four per cent of patients were successfully changed to flurazepam. Of those who did not accept flurazepam, eight per cent accepted nitrazepam, while six per cent of patients were motivated to stop all hypnotics. During the three month period of the study none of the well-known disadvantages of the barbiturates and methaqualone/diphenhydramine were seen with flurazepam. The author found flurazepam to be a very efficient hypnotic of relatively low toxicity which could be easily substituted fro barbiturates and methaqualone/diphenhydramine in the treatment of long-term insomnia.


A trial of benorylate tablets in the symptomatic relief of osteoarthritis. A two-week assessment of Benoral tablets was carried out in general practice in 171 patients with degenerative joint disease to see how symptomatic response related to selected presenting features of the disease. A short history, less severe initial state and multiple joint involvement were each associated with a better response. Overall 84-4% of patients reported Benoral tablets to have helped relieve their symptoms and a high proportion preferred Benoral to their previous anti-arthritic medication.


Temperature dependence of adenylate cyclase activity from rat white adipocytes. The effects of temperature on adenylate cyclase (AC) activity from rat white adipocytes were studied. Arrhenius plots of the data were found to be biphasic for basal AC activity, with a break near 27 degrees C. Noradrenaline and corticotropin induced a shift in the break with a rise in energy of activation (Ea) on both sides of the break. Aabove break point only, Ea increased with respect to hormone does as a hyperbolic function. The maximum value was in the range 17-21 Kcal x mol-1. Temperature was shown to have only a slight effect on the binding capacity of corticotropin to its receptor sites. The possibility of the existence of multiple thermodynamic states for the enzyme is envisaged. Basal AC activity is thermodynamically different from the hormone-stimulated enzyme. Hormones induce changes in the basal conformation of the enzyme, and this is reflected in modifications of Arrhenius plots. The maximal state of activation reached with high doses of hormones could be interpreted as a 'desensitization' of enzyme and/or enzyme systems to membrane lipid interactions.


Amino acid replacements resulting from suppression and missense reversion of a chain-terminator mutation in Neurospora. The Neurospora crassa super-suppressor mutation, ssu-1, suppresses the auxotrophic phenotype of the mutant am(17) by inserting tyrosine at residue 313 of NADP-specific glutamate dehydrogenase, a position occupied in the wild type by glutamate. Two classes of am(17) revertants due to further mutation within the am gene have, respectively, tyrosine and leucine at residue 313. These replacements are consistent with a chain-terminating codon in am(17) of either the amber (UAG) or the ochre type (UAA), but are inconsistent with UGA. The Leu313 and Tyr313 variants of the enzyme have effective activity but are grossly different from the wild type in Michaelis constants (especially for ammonium) and heat stabilities at two different pH values. They show smaller but significant differences in these respects from each other.


Qualitative changes in fibrinogen following exposure to agents used for preparation of fibrin monomers. The solubility, clottability, thrombin clotting time and agarose gel chromatography pattern of human fibrinogen were studied after exposure to solvents commonly used to prepare fibrin monomers (0.0167 M acetic acid with 2.5 mM EDTA; 1 M NaBr, pH 5.2; 3.3 M urea, pH 7.4; 5 M urea, pH 7.4). When exposed to acetic acid at room temperature, fibrinogen precipitated almost immediately and quantitatively. Subsequent dialysis for 72 h against 0.3 M NaCl, pH 7.4, caused resolution of fibrinogen to a varying degree, the amount depending on the time of exposure. The redissolved fibrinogen showed reduced clottability, markedly shortened thrombin clotting time and a chromatographic profile that indicated large amounts of aggregates. Fibrinogen exposed to 1 M NaBr, pH 5.2, at room temperature for 1 h showed a slightly shortened thrombin clotting time and a broadened chromatographic profile. Exposure for 24 h to the same agent resulted in reduced solubility and clottability, a prolonged thrombin clotting time and progressive broadening of the chromatographic profile. Similar findings were obtained with fibrinogen exposed to 5 M urea, pH 7.4. Exposure to 3.3 M urea at pH 7.4 for 24 h, room temperature, led only to a moderate increase in solubility.


Ditazole and platelets. II. Effect of ditazole on in vivo platelet aggregation and bleeding time in rats. Ditazole (4,5-diphenyl-2-bis-(2-hydroxyethyl)-aminoxazol) is a new drug shown to inhibit prostaglandin release from rat platelets. The present study indicates that ditazole, at doses similar to those inhibiting prostaglandin formation in rat, inhibits in vivo collagen--but not ADP-induced rat platelet aggregation. In addition, ditazole does not prolong the bleeding time in rats, but even tends to shorten it. This effect could be due to the inhibition of prostaglandin formation at the side of the vascular injury produced to induce bleeding.


Reduction of nitro-BT by some components of the chloroform-methanol extract of the grey matter of the rat brain. An attempt was made to extract the substance present in the nerve fibres of the cerebral cortex and basal ganglia which reduced Nitro-BT in alkaline medium pH 9-5 [4,5]. The investigations were performed on 40 white Wistar rats of both sexes and ca. 200 g of body weight. The brains taken for studies were fixed in Baker's formalin for 1,5 hr, thereafter grinded and homogenized in chloroform-methanol solution supplemented up to 100 ml of final volume after homogenisation. Thus prepared solution was left for 24 hr at 4 degrees C temperature and than centrifuged 2000 g/min. The extract was evaporated and the sediment further investigated. The following fraction were received: 1. fraction soluble in aceton, 2. fraction soluble in ethylalcohol, 3. fraction soluble in ether, 4. fraction soluble in water and 5. the sediment. Each fraction was incubated with a standard medium containing Nitro-BT. After incubation the amount of reduced Nitro-BT in each of the incubation medium was spectrophotometrically measured. The most intense reduction was found in the incubation medium with the water fraction. The spectrophotometrically determined reduction of Nitro-BT of the water fraction compared with that of the gangliosides solution were similar. The addition into the incubation media biogenic amines and N,N-diethyl-p-phenylenediamine enhances the reduction of Nitro-BT significantly. According to the results obtained an interference of gangliosides and of the investigated amines in the reduction of Nitro-BT is suggested.


[Simple on-line digital determination of the cardiac action potential and its application]. A system of digital measuring of the cardiac action potential was constructed in order to measure quickly and accurately the resting potential or maximum diastolic potential, overshoot potential, amplitude, time for 50% repolarization and time for 90% repolarization. This system consists of a dual-beam oscilloscope, a digital voltage meter, a digital interval meter and a simple circuit constructed by operational amplifiers. The measurement of the action potential was achieved by tracing only the resting potential or the maximum diastolic potential and the crest of the action potential on the oscilloscope using another beam. The time for measurement is usually 10-15 sec and errors in measurement were considered to be negligible. This system is considered to be useful for digital measurement of the action potential of various cardiac tissues. This system was applied for observation of effects of bufetolol, an adrenergic beta-receptor blocking drug on the action potential of the dog Purkinje fibres. Bufetolol (10(-5) M) caused a slight depolarization of the maximum diastolic potential, decreased overshoot potential, amplitude and maximum rate of rise, and shortened the time for 50% repolarization of the action potential. Bufetolol (10(-4) M) additionally prolonged the time for 90% repolarization.


Phosphate uptake and involvement of binding protein in Tween-80 supplemented culture of Aspergillus fumigatus. Tween-80 supplementation in submerged culture of Aspergillus fumigatus resulted in an increase of phosphate uptake. The uptake system was characterized as saturable, energy-dependent and operating against the concentration gradient. Control and Tween 80 cultures showed similar Km values for phosphate uptake (50 micrometer). Cold osmotic shock treatment of the cultures was found to cause considerable reduction in the ability to take up phosphorus with concomitant release of the binding protein into the shock fluid. Binding protein preparation from Tween-80 supplemented cells showed more activity than that from control cells.


Variation in age at puberty in monkeys.

Variation in age at puberty in monkeys. 5 female and 3 male patas monkeys and 6 female and 3 male talapoin monkeys matured in a captive breeding colony. Age at puberty is given, and some variation discussed. The talapoin, a very small monkey, becomes adult at 4 1/2 years for females, 1 or 2 years later for males. The patas, a rather large monkey, becomes adult at 2 1/2 years, for females, and 1 or 2 years later for males. Both these ages for puberty differ from data for the rhesus monkey which has been accepted as generalizable to all Old World monkeys. Possible causes of differences between species in average age at puberty are discussed, including nutrition, environmental inconstancy, and relative size of infant and mother. It is suggested that age at first conception, a biologically more relevant index than menarche, should be considered as a potentially important adaptive variable when describing primate species.


[Acupuncture analgesia].

[Acupuncture analgesia]. The possibility of abolishing pain during operations by needling acupuncture points was detected in China 20 years ago. During the last years the Western World showed great interest in this method, which was tested in a great number of surgical operations. Acupuncture was successful, especially when it was introduced by a short conventional anesthesia. Of special importance seems the possible reduction of anesthetic agents. Though the mode of action of acupuncture cannot yet be explained completely, there exist three different hypotheses: Hypnosis and suggestion, neurophysiological and humoral mechanisms. An actual review on experiments concerning these theories is given.


[Treatment of concommitant depression in neurologic diseases with dibenzepin infusions]. A definition of concommitant depression is given. The results of infusorial therapy of Dibenzepin in 53 patients with neurological diseases and concommitant depression are reported. In 86% of all cases good or very good results could be obtained. The preparation is excellently suited for this therapy. The necessity of double therapy, namely the therapy of the basic disease as well as the therapy of the depressive syndrome is stressed.


[Blood picture in lactate acidosis. Part 2: acid-base equilibrium and lactate]. A differentiation between lactate emia (lactic acid emia) and lactate acidosis (lactic acidosis) is made. The normal value for blood lactate concentration is 1-2 mmol/1. The term lactate emia is used for lactate values between 2-6 mmol/1. The limiting value for the diagnosis of lactate acidosis should be more than 7-8 mmol/1 for the blood lactate concentration. Furthermore the different buffer mechanisms are evaluated in respect to their influence on the pH of the blood and to lactate metabolism. Especially the mechanism of respiratory compensation for metabolic acidosis is discussed. It is stated that for the diagnosis of lactate acidosis the blood-pH and the bicarbonate concentration should be measured.


[The disease entity of lactate acidosis. 3. Lactate as a metabolic product]. High blood lactate concentrations can be achieved by means of intravenous bicarbonate infusion. Metabolic production of lactic acid in this case is a compensation mechanism for the alcalosis induced by bicarbonate. This metabolic condition is called lactate alcalosis. The meaning and the diagnostic value of the lactate/pyruvate quotient and of excess lactate are discussed. A metabolic increase of the lactate/pyruvate quotient (normal values being 10-20) can be attained during the intravenous application of polyalcohols (like xylitol or sorbitol) or of ethanol. In these cases blood lactate concentration remains approximately normal. The alterations are due to the metabolism of the alcohols predominantly in the cytoplasmic compartment of the hepatocytes. The anion-gap is caused by the fact that the anions are considered only in part. However, the diagnostic value of the anion-gap is only minimum. An increase in the anion-gap with a simultaneous decrease in blood-pH is not significant for a lactate acidosis.


Disparity between insulin and proinsulin on stimulation of hepatic tyrosine transaminase. The ability of insulin and proinsulin to stimulate tyrosine transaminase in dexamethasone-treated cultured rat liver cells was compared. Insulin increased this enzyme whereas proinsulin was seemingly without effect. Since proinsulin was not degraded by these cells, failure of stimulation of hepatic tyrosine transaminase could not be due to rapid destruction of the prohormone. This is the first demonstration of an action of insulin that cannot be duplicated by proinsulin.


Iodotyrosine deiodination in the normal and acutely TSH-stimulated thyroid. The deiodination of L-MIT-125I was measured in rat thyroid homogenates and slices before and after acute TSH stimulation. Slices and homogenates were incubated with identical concentrations of tissue and substrate in the presence and absence of NADPH. 1 USP unit TSH added in vitro to thyroid slices failed to stimulate deiodination; a single in vivo ip injection of 3 USP units TSH was also unable to raise deiodinating activity. In contrast to TSH, NADPH added to homogenates and slices enhanced deiodination significantly. However, several arguments, including a review of the literature, strongly militate against the hypothesis of an increased intracellular concentration of the coenzyme NADPH being the prerequisite to enhanced deiodination. The results suggest that deiodinase activity in acutely stimulated thyroids is not limited by the intracellular concentration of the enzyme itself nor by the availability of co-enzyme. Therefore, the increased iodide release induced by acute TSH stimulation is a mere consequence of the enhanced thyroglobulin proteolysis and does not require higher enzyme concentration. It will be shown subsequently that a different conclusion must be drawn in experiments with chronic TSH stimulation.


Specific, water-soluble polypeptides in identified neurons of Aplysia californica. Application of an ethylene glycol lysis technique to extract water-soluble, low molecular weight polypeptides in Aplysia neurons, was used in conjunction with microgradient gel electrophoresis and micro-isoelectric focusing, to identify unique polypeptides in specific, identified neurons. The polypeptides found in neurons R15, R3-13, R14, and the bag cells were particularly abundant, consistent with the previously suggested neurosecretory role for these cells. Water extraction of the strongly basic polypeptides (pI 10.7) in R3-13 and R14 required an acidic lysis medium.


Distribution of beta-N-acetylglucosaminidase, hyaluronoglucosaminidase and acrosin in buffalo and goat spermatozoa. The distribution of beta-N-acetylglucosaminidase, hyaluronoglucosaminidase and acrosin in buffalo and goat sperm acrosomes was studied. The three hydrolases were found to occur in soluble and bound forms. In the bound form, they were associated with the denuded sperm and were maximally solubilized at pH 3.0. The possible role of beta-N-acetylglucosaminidase in fertilization is discussed.


[Purification and properties of the tetrahydropteroylglutamate methyltransferase from green beans (Phaseolus vulgaris) (author's transl)]. The tetrahydropteroylglutamate methyltransferase from green beans (Phaseolus vulgaris) has been purified 80-fold by ion exchange chromatography and gel filtration. Optimal methyl transfer is found at pH 6.5 and 39 degrees C. Even at 0 degrees C, however, a considerable catalytic rate is observed. The Michaelis-Menten constants for homocysteine and 5-methyltetrahydropteroylglutamate are 0.43mM and 2.4 mM, respectively. Magnesium ions enhance the activity. Even purified preparations appear to contain traces of magnesium ions firmly bound, since a residual activity is found without addition of magnesium salts. Though the reaction requires anaerobiosis, an excess of reducing agents is inhibitory. The molecular weight of the transferase, determined by gel filtration, is 40 000 +/- 6%.


Induction of placental alkaline phosphatase in choriocarcinoma cells by 5-bromo-2'-deoxyuridine. Growth of choriocarcinoma cells in the presence of 5-bromo-2'-deoxyuridine (BrdUrd) results in a 30- to 40-fold increase in alkaline phosphatase activity. The effects of BrdUrd is specific for phosphatase with an alkaline pH optimum. The induction by BrdUrd is probably not due to the production of an altered enzyme, since the induced enzyme resembles the basal enzyme in thermal denaturation and kinetic properties. Enzyme induction can be prevented by thymidine but not by deoxycytidine or deoxyuridine. The induction of alkaline phosphatase appears to require incorporation of the BrdUrd into cellular DNA. The presence of BrdUrd in the growth medium is not necessary for alkaline phosphatase induction in proliferating cells containing BrdUrd-substituted genomes. However, enzyme induction and maintenance of the induced levels of alkaline phosphatase in nonproliferating cells containing BrdUrd-substituted DNA requires the presence of the analogues in the medium. The induction of alkaline phosphatase by BrdUrd in probably an indirect process.


Effects of trypan blue treatment on the immune responses of mice. It has been reported that trypan blue treatment decreases the nonspecific resistance of mice to transplanted tumors and inhibits the in vitro cytotoxic activity of activated macrophages. We wished to determine whether this effect of trypan blue could be due to a selective inhibition of certain macrophage functions or whether it reflected a broader form of immunosuppression. We therefore tested the effects of trypan blue on a variety of immunological responses. Treatment of mice with trypan blue delayed their rejection of skin allografts and transplants of a highly antigenic syngeneic ultraviolet light-induced tumor. Trypan blue treatment of either donor or recipient decreased the local graft-versus-host reaction. Filtration of lymph node cells from trypan blue-treated donors on a nylon wool column before use in the graft-versus-host assay abrogated the depressive effect of trypan blue. A transient reduction in the blastogenic response of spleen cells to concanavalin A and lipopolysaccharide mitogens was observed after a single injection of trypan blue, but the response of lymph node cells was unaffected. The depressed response of splenic lymphocytes was not entirely reversed by removal of adherent cells. The primary and secondary hemagglutinin responses to sheep erythrocytes were unaffected in trypan blue-treated mice, and the proportion and phagocytic activity of thioglycolate-induced peritoneal macrophages were also unaltered. We conclude that treatment of mice with trypan blue selectively inhibits certain macrophage functions but, at high doses, it can also inhibit some lymphocyte activities.