Ribonuclease and deoxyribonuclease activity of exonuclease A5. A comparative study was made of the specificity and some properties of the RNase and DNase activities of exonuclease A5. The results obtained indicate that RNA and denatured DNA are hydrolyzed in the same active center of the enzyme and, consequently, exonuclease A5 is an enzyme which is not specific for the sugar of nucleic acids. The data reported are important when exonuclease A5 is used as a specific reagent in investigations of nucleic acids.


The influence of pH on the effects of 2,4-D (2,4-dichlorophenoxyacetic acid, Na salt) on Saccharomyces cerevisiae and Salmonella typhimurium. The genetic effects of 2,4-D (2,4-dichlorophenoxyacetic acid, Na salt) have been investigated in cells of the yeast Saccharomyces cerevisiae and of the bacterium Salmonella typhimurium in experiments in vitro and in vivo. Experiments in vitro showed that the killing of both yeast and bacteria is dependent on the pH in the treatment solution of 2,4-D. A dose-dependent increase of the frequency of mitotic gene conversion and mitotic recombination in yeast was observed at pH 4.50 and 4.30. In experiments in vitro with two strains of Salmonella no significant increase of the number of revertants to prototrophy was obtained. The positive correlation between survival of cells and dissociation of 2,4-D in the pH region 2.8-5.0 indicates that the cells are unable to take up dissociated 2,4-D. Therefore the survival is high at a high pH when most 2,4-D is in dissociated form, and the survival is low at a relatively low pH when more of the 2,4-D is in its undissociated form. No genetic effects were induced by oral administration of tolerable doses of 2,4-D in host-mediated assays using mice as hosts and yeast or Salmonella as indicator cells.


Physicochemical properties of Sendai virus RNA. II. Effect of ionic strength on thermostability of RNA. The dependence of the melting point (Tm) and width of the melting range (deltaTm) on the ionic strength and pH of the medium was investigated for the double-stranded RNA formed through self-hybridization during the isolation of RNA from Sendai virus. It was shown that Tm is a linear function of the logarithm of the sodium ion concentration in the range of concentrations from 10(-1) to 10(-4) M, with a slope of 11.5 degrees toward the abscissa for each order of magnitude. The width of the melting range increased slightly with a decrease in the ionic strength. A change in the pH of the solutions from 5 to 8 had almost no effect on the melting point or the width of the melting range. The degree of purification of the preparations of RNA and the presence of EDTA in the solutions affected the form of the dependence of the mp on the logarithm of the sodium ion concentration very strongly, especially in the region of low ionic strengths.


Induction of DNA single-strand breaks in barley by sodium azide applied at pH 3. Sodium azide (1 to 50 mM), adjusted to pH 3 and applied for 2 h to presoaked barley seeds, induced a dose-dependent frequency of single-strand breaks in DNA of non-germinating embryos. This was demonstrated by sedimentation analyses of isolated DNA samples in alkaline sucrose gradients and in neutral sucrose gradients with 80% formamide. The doses applied also inhibited dose dependently the root length, seed germination and partially the seedling height. Only the sub-lethal doses (10 and 12.5 mM) induced a low frequency of chromatid breaks and translocations in the root tip metaphases. The sedimentation rate (in alkaline sucrose gradients) of calf thymus DNA treated with sodium azide at pH 3, was similar to that of the control DNA treated with buffer (pH 3) alone.


Acceptor activity of tRNAPhe from yeasts under special conditions of aminoacylation. The reaction of aminoacylation of tRNAPhe from yeasts and the erroneous acylation of total tRNA from E. coli by yeast phenylalanyl-tRNA synthetase under special conditions was studied. It was shown that the decrease in the degree of acylation of tRNAPhe and the increase in the degree of erroneous acylation of the total tRNA from E. coli are associated with the influence of these conditions on the structure of tRNA, and not on the structure or specificity of the enzyme. It was found that under special conditions of acylation, tRNAPhe exists in two conformations: acylatable and nonacylatable. The ability for complete acylation is restored after the transfer of tRNAPhe under classical conditions of acylation. The results are discussed from the standpoint of possible mechanisms of the recognition of tRNA by aminoacyl-tRNA synthetases.


Thermodynamic parameters of helix-random coil transitions in polypeptide chains. IV. Random copolymers of L-alanine with L-glutamic acid. pH-Induced helix-random coil transitions in random copolymers of Ala with Glu have been investigated in order to determine the effect of Ala on the stability of the helical state of polyglutamic acid. The free energies for the transfer of one uncharged Glu residue from a random coil to a helix (deltaGo) have been determined from potentiometric titration curves by the method of Zimm and Rice. It has been shown that the introduction of Ala hampers the transfer of a Glu residue from a random coil to a helix (reduces -deltaGo), although Ala itself is a helix-forming residue, i.e., its free energy decreases during helix formation. This has suggested that its introduction weakens the helix-stabilizing interactions between the uncharged Glu residues (apparently hydrogen bonds). The evaluation of the intrinsic helix-random coil equilibrium constant s for uncharged Glu residues with consideration of this situation yields a value which is smaller than the value of s for (Glu)n and in good agreement with the theoretical values.


Use of amylum derivatives for isolation of amylolytic enzymes. In a leading article literature is reviewed concerning isolation of amylolytic enzymes by adsorption on differently modified starches, resp. on other adsorbents. DEAE amylum, DEAHP amylum and DEAE-Sephadex A 25 were found to be most suitable adsorbents. The other adsorbents examined did not reach claimed parameters.


Labilization of the phosphoester linkage in enzyme-inhibitor complexes of aspartate aminotransferase. Individual enzyme-inhibitor complexes with characteristic absorption spectra have been obtained as a result of the reaction of the apoenzyme of aspartate aminotransferase with Nalpha-(5'-phosphopyridoxyl)-L-glutamic acid, Nalpha-(5'-phosphopyridoxyl)-D-glutamic acid, and Nalpha-(5'-phosphopyridoxyl)-L-pyroglutamic acid. The stability of the enzyme-inhibitor complexes has been investigated under various conditions, viz., reactivation by the coenzyme, denaturation by urea, variations in the pH. It has been shown that the complexes formed by the last two inhibitors are reactivated by pyridoxal-5'-phosphate and that the inhibitor can be released under mild conditions. The enzyme-inhibitor complex formed by Nalpha-(5'-phosphopyridoxyl)-L-glutamic acid, on the other hand, was not reactivated by the coenzyme. Pyridoxylglutamic acid has been isolate in attempts to release the inhibitor. The dephosphorylation of the inhibitor has been associated both with the hydrolysis of a phosphate bond involving the enzyme and with the phosphorylation of aspartate aminotransferase. A 32P peptide containing 13 amino acids has been isolated from the tryptic hydrolysate of the enzyme-inhibitor complex (formed by a 32P inhibitor). The data obtained have been interpreted on the basis of an assumption that the phosphate group of the coenzyme has an active role in the enzymatic transamination reaction.


Isolation of amylolytic system of Aspergillus oryzae by sorption on DEAHP amylum. Conditions of effective sorption of amylolytic enzyme from a solution or from fermentative liquid on DEAHP amylum were studied. Isolating action is in a direct dependence on the relation between activity and amount of DEAHP amylum, the curve of this dependence was illustrated. The enzyme can be released by elution or adsorbate can be used in a pulverised from. In the conclusion of the work laboratory isolation technique is described.


[Fauna and ecology of bloodsucking mosquitoes of Evenkia]. This paper presents data on the specific composition, number, hatching sites, seasonal and daily activity of mosquitoes attacking man and reindeer and the influence of weather factors on the attacking activity of mosquitoes in Central Siberia. 23 species of 3 genera are reported from Central Siberia as follows: Anopheles maculipennis, Culiseta alaskaensis, Aedes beklemishevi, A. cantans, A. caspius dorsalis, A. cataphylla, A. communis, A. cyprius, A. diantaeus, A. excrucians, A. fitchii, A. flavescens, A. hexodontus, A. impiger, A. intrudens, A. leucomelas, A. nigripes, A. pionips, A. pullatus, A. punctor, A. rempeli, A. stricticus, A. cinereus.


[Nature of the enzymes participating in the transformation of proinsulin into insulin]. A study was made of the enzymes of the islands of Langerhans which could participate in the transformation of proinsulin into insulin. The homogenate of the islands of Langerhans of rat and man catalized the hyppuril-L-arginine splitting at pH 5.4-5.8 and 6.8-7.2 which was completely blocked with N-ethyl maleimide. The enzyme of the islands with the optimum action pH of 5.4-5.8 was similar to the enzyme of the exocrine tissue and was possibly a catheptic carboxypeptidase. The second enzyme of the islands differing from the exocrine carboxypeptidase could apparently participate in the insulin formation from the intermediate forms of proinsulin. In the formation of these proinsulin fomrs the participation of the enzyme of the endopeptidase character with a more acid optimum of the action pH is supposed.


[Laparoscopic diagnosis of cryptorchism]. On the basis of observations of 28 patients suffering from cryptorchism in which laparoscopy was conducted for the purpose of diagnosis the authors came to the conclusion on the expediency of using this method in the practice of endocrinologist's work.


[Change in the activity of tyrosine aminotransferase in the tissues of rabbits with various levels of corticosteroids in the body]. Experiments were conducted on rabbits. As revealed, hypocoriticism was accompanied by a reduction of the tyrosineaminotranspherase in the liver, muscles and blood plasma; the enzyme activity was unchanged in the brain and the spleen. An increase of the corticosteroid level in the organism after the administration of hydrocortisone to the intact and adrenalectomized animals led to increase of the enzyme activity in the tissues under study; the effect of hydrocortisone action depended on the initial hormonal background in the organism and the duration of the hormone administration. A single ACTH administration to the intact rabbits was accompanied by increase in the enzyme activity in the liver and the spleen, whereas to the adrenalectomized animals--in the brain, muscles and the blood plasma. A repeated administration of both hormones decreased the enzyme activity in the brain and the liver.


A monomeric form of pyruvate kinase in human pyruvate kinase deficiency. A mutant pyruvate kinase (ATP:pyruvate 2-O-phosphotransferase, EC 2.7.1.40) from human erythrocytes which is easily separated into monomers and dimers by gel chromatography is described. Tht mutant enzyme shows almost the same pH optimum and thermostability as normal enzyme, but has a decreased stability on shaking with air, a decreased Km for phosphoenolpyruvate and a loss of allosteric properties. The apparent Km values for phosphoenolpyruvate of tetramers and monomers were the same. The tetrameric enzyme was slightly activated by fructose-1,6-diphosphate but the monomeric form was not. The tetrameric enzyme was found to dissociate spontaneously to dimeric and monomeric forms.


Membrane-associated assembly of M13 phage in extracts of virus-infected Escherichia coli. Assembly of coliphage M13 is known to occur as the viral DNA crosses the cytoplasmic membrane, shedding its virus-coded DNA unwinding protein and acquiring from the membrane approximately 2400 copies of the major coat protein. Conditions are described in which extracts of M13-infected E. coli and membranes prepared from such extracts will support virus assembly at a rate equivalent to that of intact cells. Extracts prepared from cells infected with temperature-sensitive M13 mutants in genes 1, 3, 4, or 5 are temperature-sensitive in this cell-free assembly reaction. Phage assembly in vitro requires magnesium and as yet an unidentified heat-stable cofactor of low molecular weight. The rate of virus assembly is approximately linear with respect to extract concentration over a 10(4)-fold range, consistent with the observation that the entire M13 assembly activity copurifies with the cell membrane fraction.


Catecholamine binding to the beta-adrenergic receptor. The adenylate cyclase-coupled beta-adrenergic receptors of frog erythrocyte membranes have been identified by direct radioligand binding techniques using the potent catecholamine agonist (+/-)[3H]hydroxybenzylisproterenol (2-[3, 4-dihydroxyphenyl]-2-hydroxy-1', 1'-dimethyl-2'-[4-hydroxyphenyl]-diethylamine). The successful experimental conditions included the use of (i) high concentrations of catechol and ascorbic acid to suppress nonreceptor binding, (ii) a very potent radiolabeled catecholamine (10 times more potent than isoproterenol), and (iii) membranes rich in binding sites for beta-adrenergic receptors. Thus, previous problems in accomplishing successful catecholamine binding to the beta-receptors have been overcome. The binding sites identified with (+/-)[3H]hydroxybenzylisoproterenol in the erythrocyte membranes have all the characteristics expected of true beta-adrenergic receptors. These include rapidity of binding, saturability, specificity for beta-agonists and antagonists, and stereospecificity [(-)isomers more potent than (+)isomers]. Physiologically inactive compounds containing a catechol moiety do not compete for occupancy of these binding sites. Dissociation of the radiolabeled agonist from the receptors is slow and incomplete in the absence of guanine nucleotides. In the presence of nucleotide, however, dissociation is rapid and complete. beta-Adrenergic agonists and antagonists compete for the (+/-)[3H]hydroxybenzylisoproterenol binding sites in a fashion parallel to their competition for the receptors, as previously delineated with the beta-adrenergic antagonist (-)[3H]dihydroalprenolol.


Trans-synaptic induction of adrenomedullary tyrosine hydroxylase activity by choline: evidence that choline administration can increase cholinergic transmission. Twenty-four hours after rats receive choline chloride (20 mmol/kg, by stomach tube) the activity of tyrosine hydroxylase [tyrosine 3-monooxygenase; L-tyrosine, tetrahydropteridine:oxygen oxidoreductase (3-hydroxylating), EC 1.14.16.2] increases by 31% within adrenomedullary chromaffin cells. This treatment also causes major elevations in the levels of choline and acetylcholine within the adrenal gland; however, acetylcholine levels return to normal by 16 hr after the choline is given. The daily administration of 10 or 20 mmol/kg of choline for 4 days elevates adrenal tyrosine hydroxylase activity by 29% or 51%, respectively. Such increases in tyrosine hydroxylase activity are not observed in animals given ammonium chloride, another basic chloride-containing compound, by stomach tube or in animals treated with cycloheximide, an inhibitor of adrenal protein synthesis. They are also absent in denervated adrenals. These observations demonstrate that the increase in presynaptic acetylcholine levels produced by giving animals the neurotransmitter's precursor (choline) can be associated with parallel changes in the transmission of signals across cholinergic synapses, probably because more of the transmitter is released per nerve impulse.


Ionic regulation in genetic translation systems. The polyelectrolyte theory can provide an interpretation of the interdependence of pH, ionic strength, and polyamines one observes in the activity of ribonuclease acting on RNA. According to this theory: (i) A nucleic acid-enzyme complex and the suspending medium may be considered as two phases in equilibrium, even though within limits, the complex is soluble in water. (ii) The enzymatic catalysis is under tight control of the electrostatic potential generated by the system. Consequently, modification in electrostatic potential will induce a concomitant change in activity. (iii) The electrostatic potential can be modified through action on the system of "modulators", either "external" (ionic strength, pH, temperature, etc.) or "internal" (specific ligands, substrates, protein factors, etc.). Similarities between the reaction of ribonuclease (ribonuclease 3'-pyrimidino-oligonucleotidohydrolase; EC 3.1.4.22) and RNA and those observed with highly organized systems catalyzing DNA, RNA, and protein synthesis suggest that the electrostatic potential also provides an important regulatory mechanism in genetic translation. In this view, an essential function of nucleic acids is to provide their enzyme partners with polyanionic microenvironments within which their catalytic activities are controlled by variation in physicochemical parameters, including the proton concentration induced through "modulation" of the local electrostatic potential.


Catecholamine hormone receptor differences identified on 3T3 and simian virus-transformed 3T3 cells. Identification and characterization of hormone receptors on the cell surface is an effective tool for studying the plasma membrane. Using the direct binding of a radiolabeled antagonist, (-)[3H]alprenolol, to crude membrane preparations, and a physiological response (cellular cyclic AMP levels), I demonstrated a catecholamine (beta-adrenergic) hormone receptor site coupled to a catecholamine responsive adenylate cyclase [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1] on 3T3 and simian virus 40 (SV40)-transformed 3T3 cells. At a concentration of 1 muM, epinephrine and isoproterenol elevate cellular cyclic AMP levels 8- and 12-fold, respectively, in both cell lines. Norepinephrine was also a potent agonist on 3T3 cells (8-fold stimulation), but SV3T3 cells showed a lesser (2-fold) response to this hormone. The specificity of the physiological response (as well as the direct binding studies using the alprenolol radiolabel) is indicated by the increased effectiveness of (-) compared to (+) stereoisomers, rapid and reversible kinetics (steady state within 2 min), high affinity (Kd approximately 30 nM) and saturability (indicating a finite number of hormone receptors). These hormone receptor studies indicate the 3T3 cells have a beta1 adrenergic receptor while the SV3T3 cells have a receptor with beta2 qualities. In addition, the number of beta-adrenergic hormone receptors appear to be increased in the normal 3T3 cells by approximately 2-fold over the SV3T3 cells (300 versus versus 120 femtomol/mg of protein).


Genetic control of renin activity in the submaxillary gland of the mouse. Administration of androgen to female mice is known to increase the level of several proteins in the submaxillary gland, including nerve growth factor, epidermal growth factor, esteroproteolytic activity, and renin. In the present study, renin activity has been assessed in extracts of submaxillary gland of female mice from two inbred strains (SWR/J and C57BL/10J), from F1 and F2 hybrids, and from backcrosses between F1 and parental strains. In both uninduced and induced mice, renin activity of submaxillary gland was more than 100-fold greater in SWR/J than in C57BL/10J mice as measured by either an enzymatic assay or an immunodiffusion method. This difference was not due to differences in plasma testosterone levels between the strains, and the enzymes from the two strains had similar pH optima, substrate specificities, heat stabilities, and apparent Michaelis constants. In the submaxillary gland the difference was relatively specific for renin because increases in esteroproteolytic activity, nerve growth factor, and epidermal growth factor after androgen treatment appeared to be similar in both strains. Studies with the various hybrids indicate that the difference in renin activity between the two strains is apparently due to a single regulatory gene.


Alterations of spore coat processing and protein turnover in a Bacillus cereus mutant with a defective postexponential intracellular protease. A mutant with an alteration in the major intracellular serine protease produced by postexponential Bacillus cereus was isolated by screening mutants defective in spore germination. The purified enzyme from the mutant is more labile to heat and alkaline pH than the protease from the wild type. Protease activity appears at the same time as in the wild type but only reaches 50% of the specific activity and decays more rapidly during sporulation. Coincident with the decay is a decrease in the rate of protein turnover. Generation of amino acids by turnover seems to be important for sporulation because the number of spores produced by the mutant is increased 4- to 10-fold by addition of casamino acids. As anticipated, the mutant produces spores that germinate poorly but, surprisingly, these spores are very deficient in coat protein. Coat antigen is present in cell extracts of mutant and wild type, however, both as large molecules not found on mature spores and as spore coat protein monomers. The large molecules rapidly disappear in a pulse chase experiment in the wild type with some increase in the coat monomers. In mutant extracts, however, this large coat antigen is slowly and improperly processed.


Dehydrogenase and transhydrogenase properties of the soluble NADH dehydrogenase of bovine heart mitochondria. The soluble NADH dehydrogenase of low molecular weight, isolated from complex I (NADH:ubiquinone oxidoreductase, EC 1.6.5.3) of the respiratory chain, has been shown to have NADPH dehydrogenase and NADPH leads to NAD transhydrogenase activities. Both activities are greatly increased in the presence of added guanidine-HCl and at pH values less than 6.5. The chromophores of the soluble enzyme (flavin and iron--sulfur centers) are reduced by NADH and NADPH to the same extent. The latter reduction is extremely slow, and is considerably stimulated in the presence of guanidine-HCl. The soluble dehydrogenase has little or no NADH leads to NADP and NADPH leads to NADP transhydrogenase activity. The former reaction is known to be energy-linked in submitochondrial particles; the latter was shown in the present studies also to be energy-linked. In view of the above and earlier results, possible mechanisms for dehydrogenation and transhydrogenation (nonenergy-linked and energy-linked) involving reduced and oxidized NAD and NADP are proposed.


31P nuclear magnetic resonance studies of glycogen phosphorylase from rabbit skeletal muscle: ionization states of pyridoxal 5'-phosphate. 31P nuclear magnetic resonance (NMR) at 72.8 MHZ has been used to study glycogen phosphorylase from rabbit muscle (1,4-alpha-D-glucan:orthophosphate alpha-glucosyltransferase, EC 2.4.1.1) at concentrations as low as 25 mg/ml, using a WH-180 wide-bore superconducting spectrometer. The use of a thio analogue for 5'-AMP and arsenate for inorganic phosphate allowed the observation of three distinct forms of enzyme-bound pyridoxal 5'-phosphate at --0.2 ppm (Form I), --2 to --3 ppm (Form II), and --3.5 ppm (Form III) relative to triethylphosphate. Conversion of I to III occurs by activation of phosphorylase either by formation of a ternary complex of phosphorylase b with effector and arsenate or, more efficiently, by direct phosphorylation to give the a form of the enzyme. The ionization state and exposure to solvent of each of the three forms is inferred from the 31P NMR data.


High-resolution 31P nuclear magnetic resonance studies of metabolism in aerobic Escherichia coli cells. 31P nuclear magnetic resonance spectra at 145.7 MHZ were obtained of concentrated suspensions of E. coli cells. The position of the Pi resonance was used to determine the pH, and in most experiments it was possible to distinguish the intracellular (pHin) and extracellular (pHex) values. During respiration pHin approached 7.55, while pHex varied from 6.0 to 8.0. With succinate as a carbon source and in a N2 environment, pHin - pHex. Upon addition of glucose, pHin greater than pHex. In the presence of an ATPase (adenosinetriphosphatase; ATP phosphohydrolase; EC 3.6.1.3) inhibitor dicyclohexylcarbodiimide, pHin remained equal to pHex even in the presence of glucose. In other experiments, oxygenation brought pHin above pHex even in the presence of dicyclohexylcarbodiimide. These experiments are consistent with Mitchell's hypothesis that, first, delta pH can be created by the reversal of the ATPase reaction and, second, that protons are pumped outward during respiration. In addition to Pi, about 10 more resonances were resolved, several of which were assigned to different phosphate metabolites.


Intracellular binding of radioactive hydroxocobalamin to cobalamin-dependent apoenzymes in rat liver. We identified previously an intracellular cobalamin (Cbl) binding protein(s) in cultured human fibroblasts, distinct from known Cbl "R" binders and absent from mutant cells deficient in the synthesis of the two Cbl coenzymes. In order to further characterize this binding activity, we have investigated its homologue in rat liver. After being transported to the liver by the serum protein transcobalamin II, [57Co]Cbl was bound by at least two distinct proteins, one cytosolic, the other mitochondrial. Labeled Cbl bound to cytosolic protein faster than or prior to the mitochondrial protein. With time there was a decline in radioactivity associated with the cytosolic binder and a coordinate increase in that associated with the mitochondrial binder. Although both proteins cochromatographed on Sephadex G-150 and had apparent molecular weights of 120,000, they were separated into two discrete components by polyacrylamide gel electrophoresis and by DEAE-cellulose chromatography. The cytosolic binder cochromatographed with N5-methyltetrahydrofolate:homocysteine methyltransferase activity (5-methyltetrahydropteroyl-L-glutamate:L-homocysteine S-methyltransferase, EC 2.1.1.13); the mitochondrial one with methylmalonyl CoA mutase activity (methylmalonyl-CoA CoA-carbonylmutase, EC 5.4.99.2). These proteins were distinguished further by the chemical forms of [57Co]Cbl found with them, hydroxocobalamin and methylcobalamin with the cytosolic protein and adenosylcobalamin with the mitochondrial one. These results suggest that intracellular Cbl binding activity in rat liver can be accounted for by attachment of Cbl to the two known Cbl-dependent apoenzymes, methylmalonyl CoA mutase and methyltetrahydrofolate methyltransferase. The mechanism and significance of the observered binding protein deficiency in mutant human fibroblasts must, therefore, be re-evaluated.


Recognition of two intracellular cobalamin binding proteins and their identification as methylmalonyl-CoA mutase and methionine synthetase. The granulocyte R-type cobalamin binding protein delivers cobalamin (Cbl) exclusively to hepatocytes, and transcobalamin II delivers Cbl to various mammalian cells. Both protein-Cbl complexes enter cells by pinocytosis, and the protein moieties are rapidly degraded in lysosomes. The liberated Cbl is subsequently bound to a high-molecular-weight intracellular cobalamin binding protein (ICB). The nature of ICB-Cbl is unknown but appears important because ICB-[57Co]Cbl is missing from cultured fibroblasts of a group of patients whose cells take up CN-[57Co]Cbl normally but do not convert it to either of its coenzyme forms. We have examined supernatants of sonicated rabbit livers and have found that 65% of the total endogenous Cbl elutes from Sephadex G-150 as ICB-Cbl and that this fraction also contains the two mammalian Cbl-dependent enzymes, methylmalonyl-CoA mutase (methylmalonyl-CoA CoA-carbonylmutase;EC 5.4.99.2) and methionine synthetase (tetrahydropteroylglutamate methyltransferase; 5-methyltetrahydropteroyl-L-glutamate:L-homocysteine-S-methyltransferase; EC 2.1.1.13). Gradient elution from DEAE-Sephadex reveals that 90--95% of the ICB--Cbl elutes with methylmalonyl-CoA mutase and 5--10% elutes with methionine synthetase. ICB--[57Co]Cbl first appears 2 hr after the intravenous injection of CN[57Co]Cbl bound to granulocyte R-type protein. This ICB-[57Co]Cbl is associated with either methylmalonyl-CoA mutase or methionine synthetase although the latter appears to be formed at a relatively faster rate. Our studies indicate that mammalian cells contain two ICBs, that these proteins are methylmalonyl-CoA mutase and methionine synthetase, and that the primary abnormality in the group of patients mentioned above lies at a step that is common to the formation of both Cbl coenzymes and that precedes the stable binding of Cbl to both methylmalonyl-CoA mutase and methionine synthetase.


Affinity labeling of gamma-glutamyl transpeptidase and location of the gamma-glutamyl binding site on the light subunit. Gamma-Glutamyl transpeptidase, which consists of two nonidentical subunits, is rapidly inactivated with respect to its transpeptidase and hydrolase activities by the gamma-glutamyl analogs 6-diazo-5-oxo-L-norleucine and L-azaserine. Inactivation, which is prevented by gamma-glutamyl substrates (but not by acceptor substrates), is accelerated by maleate, which was previously shown to enhance utilization of glutamine by transpeptidase. 6-Diazo-5-oxo--norleucine reacts specifically, covalently, and stoichiometrically at the gamma-glutamyl site of the enzyme, which was localized through studies with 6-diazo-5-OXO-[14C]norleucine to the light subunits of both the transpeptidase of rat kidney (which has subunits of molecular weights 22,000 and 46,000) and the transpeptidase of human kidney (which has subunits of molecular weights 22,000 and 62,000). The findings, which indicate that these enzymes have similar gamma-glutamyl binding subunits, are relevant to the structure-function relationships of this membrane-bound enzyme and its physiological role.


Detection in bovine adrenal cortex of a lipoidal substance that yields pregnenolone upon treatment with alkali. Bovine adrenal cortical tissue contains a lipoidal derivative of pregnenolone (3beta-hydroxy-pregn-5-en-20-one) from which the free steroid can be liberated by treatment with alkali. Evidence for the presence of such an entity comes from examination of a nonpolar extract of tissue from which pregnenolone and its sulfate had been removed by chromatography. Treatment of the nonpolar fraction with alkali followed by exhaustive chromatographic analysis led to the detection of pregnenolone. The steroid was identified by both gas chromatography/mass spectrometry and double isotope procedures. Quantitative analysis indicated that the three forms of pregnenolone are present in bovine adrenal cortical tissue in the following amounts (mug/kg): lipoidal derivative, 290; free steroid, 435; and sulfate, 65. Because the only known metabolic function of pregnenolone is to serve as a precursor of the steroid hormones, these findings have far-reaching implications for steroid hormone biochemistry.


Regulation of hepatic nuclear guanylate cyclase. In immunohistochemical studies of rat liver tissue slices and purified nuclei, adenosine 3':5'-cyclic monophosphate (cAMP) and guanosine 3':5'-cyclic monophosphate (cGMP) immunofluorescence on the nuclear membrane are sequentially increased after glucagon administration. An explanation for the increased cGMP immunofluorescence was sought in experiments in which guanylate cyclase [GTP pyrophosphate-lyase (cyclizing), EC 4.6.1.2]activity of hepatic subcellular fractions was determined. The results showed that a nuclear guanylate cyclase exists which can be distinguished from the soluble and crude particulate guanylate cyclases. The activity of the nuclear enzyme was increased by 35% in nuclei isolated from rats 30 min after glucagon injection, the time at which maximal nuclear membrane cGMP immunofluorescence is observed. Because glucagon altered both cAMP location and levels prior to the observed changes in nuclear cGMP metabolism, the hypothesis that cAMP acted as the second messenger was tested. In vitro incubation of nuclei isolated from control rats with 10(-5) M cAMP produced a 25% increase in nuclear guanylate cyclase activity. With nuclei isolated from glucagon-treated rats, no significant increase in enzyme activity was observed; this indicates that maximal stimulation of nuclear guanylate cyclase by cAMP occurred at levels that are obtained in vivo after glucagon administration. These findings suggest that hepatic nuclear cGMP content may be regulated by a specific organelle guanylate cyclase and that cAMP may be one of the determinants of this enzyme's activity.


Effect of batrachotoxin on the electroplax of electric eel: evidence for voltage-dependent interaction with sodium channels. Batrachotoxin under certain conditions has a strong depolarizing effect on the innervated membrane of the monocellular electroplax preparation from the electric eel, El-ectrophorus electricus. No effect is observed when the toxin (50-200 nM) is applied to the resting membrane for periods up to 1 hr. However, if the membrane is exposed to batrachotoxin  and the cell is subjected to stimulation at a stimulus voltage slightly above the threshold for action potential firing, a progressive prolongation of the action potential and concomitant progressive depolarization of the innervated membrane is observed. When the membrane is depolarized by 15-20 mV, a further abrupt all-or-none depolarization occurs, and the potential attains a steady-state value between 0 and -10 mV. Brief stimulation of a cell in the presence of batrachotoxin is sufficient to define a batrachotoxin-treated cell, even though negligible depolarization occurs. If depolarizing agents such as carbamoylcholine or potassium chloride are introduced to such a cell in concentrations that normally produce a 20-30 mV depolarization, the abrupt all-or-none depolarization immediately occurs. All-or-none depolarizations arising from either electrical stimulation or depolarizing agents are unaffected by d-tubocurarine but are completely reversed by tetrodotoxin. Batrachotoxin thus appears to activate only the action potential sodium channels. In the batrachotoxin-treated membrane, these channels can attain stable steady states in either a closed configuration at the normal resting potential or in an open configuration after complete depolarization. A striking hysteresis cycle thus can be generated, which is strongly indicative of a voltage-dependent interaction of the toxin with the action potential sodium channels.


Phencyclidine-induced rotational behavior in rats with nigrostriatal lesions and its modulation by dopaminergic and cholinergic agents. The peripheral administration of the psychotomimetic drug phencyclidine (1-(phenylcyclohexyl) piperidine hydrochloride) (PCP) induces a dose-related ipsilateral rotation in unilateral substantia nigra electrolytically-lesioned rats. The intensity of this rotation can be modulated by administration of various dopaminergic and cholinergic agents. Injection of alpha-methylparatyrosine methylester (125 mg/kg) or haloperidol (1 mg/kg) inhibited the ipsilateral circling behavior. Pimozide (1 mg/kg) also inhibitied the rotation, but to a lesser extent. The injection of the anticholinergic agent trihexyphenidyl (5 mg/kg) potentiated, and the cholinomimetic drug arecoline (5 mg/kg), depressed the rotation induced by PCP (7.5 mg/kg), It is probable that PCP possesses significant dopaminergic and anticholinergic properties. The capacity of PCP to induce rotation in this model may be related to its effects on dopaminergic and cholingergic neurons in the rat striatum. Thus, PCP may induce rotational behavior by potentiating dopaminergic transmission, by blocking cholinergic activity, or both; both of these effects have been demonstrated to be important in the generation of circling behavior in rats with nigrostriatal lesions.


Differential motor effects of intraventricular infusion of morphine and etonitazene. The motor effects produced by intraventricular infusions of morphine were compared to the effects of etonitazene. Despite the similarity in the peripheral actions of these drugs, motor effects of central infusions differed dramatically. Intraventricular morphine infusions resulted in explosive motor behavior whereas etonitazene produced extreme muscular rigidity. The periaqueductal grey (PAG) has been proposed as the substrate of morphine-induced explosive motor behavior. However, considerations of the dose of morphine and the mobility of this drug in tissue suggests that sites other than the PAG may also be involved in explosive motor behavior.


The different influence of predominantly antiadrenergic and antidopaminergic neuroleptics on the estrous cycle in rats. In experiments performed on rats, single subcutaneous doses of predominantly antidopaminergic neuroleptics (fluspirilene, pimozide, and thioproperazine in large doses) elicited persistent diestrus, i.e. pseudopregnancy. Neuroleptics with predominantly antiadrenergic action (levomepromazine, thioridazine, chlorpromazine) as well as phenoxybenzamine injected intraventricularly induced mainly prolonged estrus, i.e. blocking of ovulation. Since pseudopregnancy implies a rise of prolactin secretion, our results indirectly indicate that PIF secretion is stimulated by dopamine. The antiovulatory effect of the antiadrenergic agents, which involves an inhibition of the proestral LH surge, suggests that the discharge of LRF is mediated by an adrenergic mechanism.


The functional anatomy of the mantle complex and columellar muscle of tectibranch molluscs (Gastropoda: Opisthobranchia), and its bearing on the evolution of opisthobranch organization. An account is given of the anatomy of a series of opisthobranch molluscs principally to assess the change in importance and functioning of the mantle cavity and columellar muscle throughout the transition from prosobranch to opisthobranch organization. Intermediate steps are represented by living tectibranchs, of which Philine and Scaphander are investigated in detail, Acteon, Bulla, Haminoea, Akera, Aglaja and Gastropteron more briefly. Though an opisthobranch, Acteon has an organization typical of a monotocardian prosobranch; the remainder show trends affecting the shell and visceral mass, mantle cavity and head-foot, which resulted finally in the production of nudibranch types. It is confirmed that the adaptations exhibited by primitive tectibranchs relate to the assumption of a burrowing mode of life. Initial changes were the reduction of the nuchal area and sealing of the mantle cavity anteriorly so that it opened on the right, where it became restricted, the first perhaps prompting the sealing. A broadening and an anterior elongation of the head-foot produced a wedge to facilitate burrowing. Change in disposition of the mantle edge, incurred by differential growth, produced an involute shell with a large body whorl, alignment changing from erect to horizontal. The resultant streamlining eased infaunal progression; no vertical insinking of the viscera was involved. Subsequently the shell became reduced and finally lost. A section of the mantle edge enlarged to produce a posterior mantle lobe upon which sit both the shell and viscera, and which later became redundant as posterior elongation of the head-foot produced a slug-like form, the viscera being incorporated within the head-foot. As the nuchal area became reduced, mechanical needs prompted alteration to both the form and attachment of the columellar muscle. In Acteon the muscle is like that of a prosobranch, but the proximal region has broadened, a change of proportion required by primitive tectibranchs in order to support the floor of the mantle cavity formed from the section of mantle skirt which in prosobranchs lies on the right. This was followed by reduction and re-alignment of the entire muscle along an anteroposterior axis as emphasis changed from the muscle effecting retraction into a shell to producing contorsions of the head-foot. The shell, similarly reduced, instead of providing anchorage, became itself anchored by additional anterior and posterior attachment zones with, in more advanced forms, dorsoventral muscles of the body wall rather than longitudinal muscles fastening to the former. Importance was placed on the mutual stabilization of constituent parts of the posterior body region. Re-alignments of the muscle induced breaking up of the longitudinal muscle sheet of the head-foot to produce muscle tracts, best exhibited in those tectibranchs which swim; they are derived from both the columellar muscle and intrinsic body wall muscles...


[Electrolyte-water balance and acid-base equilibrium in brain tumor patients]. Electrolyte variations, water-balance disturbances, and acid-base equilibrium disorders observed in patients with brain tumors are due, in the majority of cases, to increases in intracranial pressure and, in a relatively small number of cases, to the particular location of the tumor. Severe pathological pictures are not, in general, observed until the ailment has advanced to a critical state. The authors, after describing the clinical pictures of the various forms of acid-base equilibrium disorders, also discuss methods of treatment. Disturbances of water balance are closely associated with the electrolyte metabolism. Consequently, it is necessary that, if a dehydrating form of therapy is used, careful attention should be given to the corresponding parameters. Disturbances of iatrogenic origin tend to produce particularly adverse effects in brain tumor patients.


Medazepam and the driving ability of anxious patients. A double-blind crossover trial of Medazepam was carried out in 14 anxious hospital patients. The mean self-adjusted dosage was 16.5 mg daily. The active drug was no more effective than placebo in relieving anxiety, which was rated both clinically and by the Middlesex Health Questionnaire (M.H.Q.) (Crown and Crisp, 1970). This may have been because the dose was relatively low for chronically anxious hospital patients. Even this dosage caused significantly higher scores on the M.H.Q. scale for depression. Braking and driving simulator tests were not adversely affected by Medazepam. In real driving conditions those taking the drug made significantly more technical, but not dangerous, errors. Pulse and blood pressure also were not affected.


Effects of oxazolam, cloxazolam, and CS-386, new anti-anxiety drugs, on socially induced suppression and aggression in pairs of monkeys. This experiment was conducted to examine effects of oxazolam, cloxazolam, CS-386, and reference drugs on socially induced suppression and aggression in pairs of monkeys. Oxazolam, cloxazolam, and CS-386, as well as other benzodiazepines, at both ataxic and non-ataxic doses, attenuated the socially induced suppression, but failed to show inhibitory effect on the on the socially induced aggression. Chlorpromazine, at both slight-sedative and non-sedative doses, reduced neither socially induced suppression nor aggression. Imipramine did not produce any significant effect in this study.


Intensive design in evaluating anxiolytic agents. The purposes of this study were: (1) to test the usefulness of intensive design in detecting the effects of an established antianxiety agent in a single patient studied for a period as brief as 8 weeks and (2) to explore the usefulness of combining intensive and extensive designs by jointly analyzing the results from several similarly treated patients. Fifteen primarily anxious, psychoneurotic patients aged 21-50 and scoring 17 or more on the Taylor Manifest Anxiety Scale were admitted to the study; and 11 completed the full treatment program. Medications were diazepam 5 mg t.i.d. and a matching placebo, administered under double-blind conditions. Patients were treated for 8 weeks, divided into 42-week blocks. In each block, the patient received diazepam 1 week and placebo the other, with the order in each block determined at random. The patient came weekly for evaluation, including, self-ratings on the Hopkins Symptom Checklist (SCL), global status, global change; reports of occupational and social function; resting pulse; reaction time; psychiatrist's ratings on the Hamilton Anxiety Scale, global status and global change. The patient also reported daily his mood on the Profile of Mood States (POMS). Mean deviations from the general trend for post-diazepam and postplacebo scores on each criterion were compared within patients. Diazepam-placebo differences on each criterion were analyzed between patients. Criteria that clearly recorded the anti-anxiety effect of diazepam as compared to placebo included the Hamilton Anxiety Scale, the psychiatrist's global status and global change ratings, the SCL Anxiety and Somatization Scales, and the POMS Anxiety Scale. Other criteria that showed a reliable diazepam effect included SCL Depression (decrease), POMS Vigor (increase), POMS Fatigue (decrease), SCL Anger (increase), and reaction time (increase). The most sensitive criteria distinguished diazepam from placebo even when results were considered only from the first 6 patients during their first 4 weeks of treatment- a total of 24 patient weeks of treatment. The factors contributing to the sensitivity of this design were investigated and discussed.


Spectrum of angiographically demonstrable renal pathology in young hypertensive patients. The renal diseases which cause systemic hypertension in the first two decades of life differ from the adult in their incidence and etiology. Seventeen patients (11 days to 20 years old), studied angiographically, demonstrated a wide spectrum of renal pathology including arterial thrombosis, fibromuscular hyperplasia, vasculitis, neurofibramatosis, cystic disease, pyelonephritis, Page kidney, and congenital anomalies.


The influence of hypoxia and acidity on the hyperthermic response of malignant cells in vitro. Colony formation of JB-1-E tumor cells was studied after hyperthermic treatment (42.5 degrees C) at a pH of 6.4 or 7.2 under hypoxic and euoxic conditions. At a pH of 7.2 and normal oxygen tension, there was a moderate decrease in colony formation with increasing duration of hyperthermic treatment (To = 65 min.). This effect was slightly enhanced under hypoxic conditions (To = 36 min.). The hyperthermic effect was enhanced to a considerably greater degree when treatment was performed at a pH of 6.4 (To = 19 min.), with no observable difference between hypoxia and euoxia. These findings indicate that environmental acidity is a determining factor in the hyperthermic effect. The hypoxic effect at a pH of 7.2 is probably due to a slight decrease in the intracellular pH caused by increased production of lactic acid.


Evidence against the release of prostaglandin-like material from isolated intestinal tissue by pure cholera toxin. Prostaglandin-like material was released from finely cut guinea-pig ileum or human intestinal mucosa during incubation with Krebs solution. The tissue inactivated some significant change in release of prostaglandin-like material when pure cholera toxin was incubated with guinea-pig ileum or human intestinal mucosa. The work is discussed in relation to the action of cholera toxin in vivo.


Multiple molecular forms of prostaglandin 15-hydroxydehydrogenase and 9-ketoreductase in chicken kidney. Prostaglandin-15-hydroxydehydrogenase and prostaglandin-9-keto-reductase were purified from chicken kidney. Both enzymes exist in multiple forms as determined by isoelectric focusing. The dehydrogenases catalyze the transformation of the functional group at C-15 but not the functional group at C-9. The preferred cofactors in these reactions are NAD+ or NADH. The 9-ketoreductases catalyze the reversible transformation of the functional group at C-9 and also the oxidation or reduction of the C-15 functional group. The preferred cofactors are NADP+ or NADPH. Bradykinin does not affect the activities of any of the three prostaglandin 9-ketoreductases. Flavin mononucleotide and the flavonoid, quercetin, as well as indomethacin, ethacrynic acid, and furosemide, inhibit all three 9-ketoreductases. An inhibitor of 9-ketoreductase isolated from chicken breast muscle also inhibits the three separable reductases, but the pattern of inhibition of the reductase that focuses at pH 5.7 differs from that of the reductases focusing at pH 7.8 and 8.2.


Studies on membrane receptor sites for serotonin in the brain. The competitive effect of 5,6-dihydroxytryptamine, morphine and chlorpromazine on the binding of serotonin (5-HT) to rat brain slices was investigated. Ths busynaptosomal localization of the binding of morphine in bovine midbrain preparations was compared to that of 5-HT and found to be considerably higher. The condensation of 5-HT and tryptamine receptor carbonyl groups in brain with phenylisopropylhydrazine was shown in vitro and vivo. Membrane particles labeled with [14C] tryptamine or 5-HT in presence or absence of sodium borohydride (NaBH4) were extracted with chloroform-methanol (C-M) 2:1. The labeled proteolipid precipitated by ether from these extracts showed on electropherograms one single radioautographic spot which was more intense with samples treated with sodium borohydride. In column chromatography, the bound radioactivity peak eluted with the gel void volume, was associated with a protein peak. The eluted, lyophilized material of this fraction was extracted by chloroform methanol (2:1) thus suggesting its proteo-lipid nature.


Action of glucagon and aspirin on ionic flux, mucosal blood flow and bleeding in the fundic pouch of dogs. Into vagally denervated (Heidenhain) pouches of 4 dogs 25 ml of 0.1 M HCl was instilled and removed at 30 min intervals for 6 hours. During the 4th, 5th, and 6th 30 min periods the acid instillate contained 5 mg/ml of aspirin. Aspirin significantly increased gastric-mucosal clearance of aminopyrine (mucosal blood flow), outputs of Na+, Ca++, Mg++, hemoglobin, and plasma transferrin-Cr51 into the pouch contents, and disappearance of H+ from lumen to mucosa. Glucagon, 50 mug/kg subcutaneously was given during irrigation with aspirin and again 1 hour later. Glucagon did not significantly affect loss of acid from lumen to mucosa or the increase in Na+, K+, Ca++, and Mg++ effluxes caused by aspirin. Glucagon significantly decreased mucosal blood flow and the hemorrhage and loss of plasma protein into the instillate induced by aspirin.


The Wien effect in compensated metabolic acidosis. CSF and blood acid-base values were measured in compensated metabolic acidosis, induced in anesthetized dogs by infusion of dilute HCl during hyperventilation. We observed cerebral blood flow-related steady-state differences in PCO2 between CSF and arterial venous blood from the brain. The steady-state values of CSF-blood PCO2 differences and blood H+ activity were intermediate to those observed by us previously during uncompensated acidosis and alkalosis (J. Appl. Physiol. 34: 249-254, 1973). These results are consistent with predictions of the "charged membrane hypothesis" proposed by us to explain CSF and blood acid-base relationship during uncompensated acid-base derangements (J. Appl. Physiol. 34: 243-248, 1973).


[An unusual case of small intestine infarction of venous origin]. The evolution is presented, of a partial infarction of the small bowel, of venous origin, without apparent cause. In the 10-th day after onset, following a segmentary resection of the jejunum and termino-terminal anastomosis, the patient had another segmentar infarction of the ileon, also of venous origin, that was cured after resection. After recovery the hematological investigations evidenced a coagulation disturbance that necessitated longterm heparin therapy, a treatment that is continued 3 years after surgery. Although the repeated infarction of the small bowel of venous origin is theoretically possible the case presented appears to be unique by its evolution and the result of the medico-surgical treatment.


Postnatal changes in blood respiratory characteristics in an American opossum (Didelphis virginiana). The oxygen affinity of opossum blood changes in the postnatal period. The youngest opossums studied were 53 days of age (dated from the day of transit from vagina to pouch) and still confined to the maternal pouch: they had a blood P50 of 32.6 +/- 2.9 mm Hg. The blood P50 value then increased significantly, in two steps. First, while the young were still in the pouch, blood P50 rose secondary to a rise in the concentration of 2,3-diphosphoglycerate (DPG). Blood P50 and DPG concentration then remained stable until the animals left the maternal pouch, when DPG rose again, causing a further increment in the blood P50 which peaked at 48.7 +/- 4.5 mm Hg in animals 148 days old. Blood P50 subsequently decreased significantly, reaching the adult value (42.0 +/- 1.9 mm Hg) at about 250 days.


Hemoglobin function in stored blood, XVII. Maintenance of red cell 2,3 DPG (function) and ATP (viability) for six weeks in ACD or CPD-adenine-inosine-methylene blue. Blood preservatives containing adenine for six week storage have been prepared with inosine and methylene blue at various pH levels in order to maintain, 23-DPG levels for immediate oxygen transport upon transfusion. In one experiment, the adverse effect of a high pH on ATP maintenance was demonstrated in the presence of methylene blue and inosine. In this and other experiments  it was clear that ATP was better maintained in low pH preservatives and DPG better maintained in higher pH preservatives. However, 2,3-DPG levels were kept from falling with CPD-adenine-inosine over a wide range of pH values. A CPD-adenine-inosine preservative at a pH 5.8 maintained normal DPG levels for three weeks of storage. A similar preservative but with a pH of 6.6 maintained normal DPG levels for 35 days of storage. It is suggested that if all blood bank units are going to have normal DPG levels for optimal oxygen transport at the time of transfusion then a CPD preservative with a higher pH and/or metabolic nutrients and regulators such as inosine or methylene blue would be required.


The effect of intragastric pH-variations on the gastric acid response to insulin hypoglycaemia in healthy subjects and duodenal ulcer patients. The gastric acid response to i.v. injection of 0.15 U of soluble insulin/kg b.w. was determined in healthy subjects and duodenal ulcer patients during intragastric perfusion with water, 0.1 M HC1, and alkaline buffer (pH 8.3). Perfusion with hydrochloric acid significantly reduced the peak gastric acid output following insulin in 6 healthy subjects (reduction 45%, p less than 0.05) but had no significant effect on the peak gastric acid response to insulin in 7 DU patients (reduction 16%, p greater than 0.05). The 2.5-hour gastric acid response to insulin was, however, significantly reduced in both groups (56% and 35%, respectively) by exogenous acidification of the stomach. The gastric acid response to insulin hypoglycaemia in 3 DU patients was the same with intragastric water and alkaline buffer perfusion. The reduction of the gastric acid response to insulin hypoglycaemia by intragastric acidification corresponded to a reduced volume secretion and could not be ascribed to increased back diffusion of hydrogen ions or duodenal inhibition. These findings suggest that the gastric acid response to insulin hypoglycaemia is inhibited by a low intragastric pH in man, and that DU patients are less sensitive to the inhibitory mechanism than healthy subjects.


Pancreatic extract and the intestinal uptake of vitamin B12. III. Stimulatory effect in the presence of a non-intrinsic factor vitamin B12 binder. To determine the mechanism by which pancreatic extract (PE) corrects the malabsorption of vitamin B12 in chronic pancreatic insufficiency (CPI), the following hypotheses were investigated: Firstly, PE might stimulate the absorption of vitamin B12 by changing the intestinal pH, secondly PE might stimulate the intestinal uptake of unbound vitamin B12, thirdly PE might abolish the inhibitory effect of vitamin B12 binders on the intestinal uptake of vitamin B12 bound to intrinsic factor (IF). PE had no effect on the pH in the small intestine and did not stimulate the uptake of unbound 57CoB12 by perfused rat intestinal segments. Preincubation of 57CoB12-IF with a non-IF B12-binder from human saliva (R-binder) reduced the uptake of 57CoB12 from 18.5 pg per cm intestine +/- 3.4 S.E.M. to 7.8 +/- 1.6 (p less than 0.02). PE abolished this inhibitory effect (p less than 0.05). The results indicate that PE corrects the malabsorption of vitamin B12 in CPI by an effect on non-IF B12- binders.


Effect of changes in the intragastric milieu on competence of the gastro-oesophageal region. A study in normal subjects. Acid-reflux studies were carried out in 10 healthy subjects in the basal state, during continuous infusion of pentagastrin (0.015 mug/kg body-weight) after bolus injection of insulin (0.2 IU/kg bodyweight), and after intragastric instillation of 200 ml hydrochloric acid. Basal gastro-oesophageal sphincter pressure and rise in intragastric pressure on leg raising were measured by means of perfused catheters. The increase of intragastric acidity during infusion of pentagastrin and during insulin-induced hypoglycaemia was not accompanied by changes in the competence of the gastro-oesophageal region. Instillation of hydrochloric acid was followed by a significant enhancement of the reflux tendency. Changes in intragastric pressure-rise were not demonstrated in any of the series of investigation. Gastric acid secretion and its significance at the evaluation of the results of reflux studies by means of pH-measuring equipment has not been clarified in patients. It can therefore reasonably be demanded of future acid reflux studies that details have to be stated with regard to acid secretion, and that these should be taken into account at the assessment of the results of the study.


Continuous oesophageal pH recording and acid-clearing test. A study of reproducibility. Ten investigations of acid reflux by means of 12-hour continuous pH monitoring at the distal end of the oesophagus, and 10 acid-clearing tests were performed within 6 weeks on the same volunteer with the purpose of examining the reproducibility of the results of these tests. Intragastric pH was studied over 12 hours and proved to be under 3 during the whole period of investigation. For the acid reflux test the coefficient of variation was 0.61-0.94, depending on the criteria for reflux. For the acid-clearing test the coefficient of variation was 0.22. For both tests the results of the separate investigations varied within normal ranges.


Theta-bearing cells in the bone marrow of thymus-deprived mice. Numbers and nature. Theta-bearing cells in lymphomyeloid tissues of thymus-deprived and normal mice have been studied by the use of anti-theta antiserum and cytotoxicity tests in addition to functional tests. In contrast to the findings in peripheral lymphoid tissues, increased percentages and numbers of theta-bearing cells were found in the bone marrow of neonatally and nude mice as compared with normal and sham-thymectomized mice. In adult thymectomized mice, percentages comparable to those in sham-operated littermates were found. The findings were not due to irrelevant antibodies in the anti-theta antiserum, and neonatally thymectomized mice grafted with a thymic lobe showed percentages of theta-positive cells in the bone marrow comparable to those of sham-operated animals. Adrenalectomy did not lead to diminished percentages of theta-positive cells in the bone marrow of neonatally thymectomized mice, and the serum levels of hydrocortisone and corticosterone were within normal ranges in thymus-deprived mice. The mitogen responses and graft-versus-host activity of bone marrow cells from neonatally thymectomized mice suggest that most theta-positive cells in the bone marrow of these mice are functionally immature cells.


Tris buffer attenuates acetylcholine responses in Aplysia neurons. The commonly used buffering agent tris(hydroxymethyl)methylamine (tris) antagonizes the action of iontophoretically applied acetylcholine on neurons of Aplysia californica. Concentrations of 5 to 10 millimolar tris markedly reduced both excitatory and inhibitory responses.


Injuries from sea urchins.

Injuries from sea urchins. Injuries from sea urchins result from penetration of the calcareous spines into the skin. Local pain of several days' duration is the most common symptom, but systemic reaction from toxins found in certain species can occur. There is no uniformly accepted successful treatment other than cleansing the wound. Attempts to remove the imbedded spines can increase the severity of the reaction.


The effect of a sodium citrate preparation compared with an aluminium-magnesium hydroxide preparation on the urinary pH of normal subjects. The effects of a sodium citrate preparation in two dosage regimens (4 g 4 times daily and 8 g 4 times daily) and of an aluminium-magnesium hydroxide suspension (15 ml 4 times daily) on the urinary pH of 19 healthy subjects were compared. The sodium citrate preparation in both dosages proved to be superior to the aluminium-magnesium hydroxide suspension in elevating the urinary pH. Urinary pH values as high as 8 were reached with the sodium citrate preparation. Blood pH, blood gases and electrolyte changes were within normal limits.


Medical treatment of hypertension.

Medical treatment of hypertension. The management of hypertension with current hypotensive drugs on the South African pharmaceutical market is reviewed. The advent of the use of beta-adrenergic blocking agents and vasodilators in the treatment of hypertension is promising.


[Endocrine polyadenomatosis with carcinoid tumor]. The authors review 26 cases of multiple endocrine tumours with presence of a carcinoid tumour. In 44% the carcinoid was localised to the bronchus, in 20% of cases to the small intestine or duodenum. In 76% of cases during multiple endocrine tumours, the carcinoid appeared in embryological derivatives of the anterior part of the intestine. No carcinoid syndrome was reported. The difficulty of histological distinction has led to the description of carcinoid islet cell tumours. These facts fit in with the APUD concept.


Clothiapine in the management of schizophrenia. Forty Black men diagnosed as schizophrenic and admitted to Ingutsheni Hospital during a period of 3 months, were allocated alternately to treatment with either clothiapine or chlorpromazine. Six patients were excluded from the trial because of an incorrect diagnosis and 34, 17 in each group, completed the trial. The 2 groups were comparable for both severity and symptoms of their illnesses. Degrees of regression of psychotic symptoms as assessed by the Brief Psychiatric Rating Scale, were comparable for the 2 groups. Adverse effects were not troublesome with clothiapine and there was no evidence of disturbed liver function, but haemoglobin values and white cell counts were sometimes decreased. EEG studies showed that clothiapine produced an increase in the slow activity but no paroxysmal acitvity. It was concluded that clothiapine is a valuable drug for the management of actue schizophrenia.


Interpretation of alveolar-arterial oxygen tension difference. In this study, an assessment is given of errors resulting from the use of the alveolar-arterial oxygen difference determined on both room air and 100% oxygen in estimating changes in total shunt fraction of 41 patients hospitalized with long bone fractures. In 113 studies, changes in alveolar-arterial oxygen difference in 29 patients were in the opposite direction to changes in shunt fraction. Based upon these studies, changes of less than 45 millimeters in the arterial oxygen tension determined with a patient breathing 100% oxygen are not reliable indicators of direction of change in shunt fraction. In 126 studies, the shunt fraction determined from arterial and mixed venous oxygen contents in 71 patients was greater when determined on 100% oxygen than when determined on room air, a possible indication of the induction of alveolar or small airway collapse. The errors in estimation of shunt fraction due to assuming a value for arteriovenous oxygen content difference become larger as total shunt fraction increases; in particular, use of the alveolar-arterial oxygen difference as a guide to serial changes in pulmonary dysfunction can be particularly misleading when the alveolar-arterial oxygen tension difference is so large that the arterial hemoglobin is less than fully saturated on 100% oxygen. Use of mixed venous samples was found necessary, in these instances, to avoid large errors in estimation of total shunt fraction.


The effect of furosemide on the flow and composition of bile in the dog. The effect of furosemide, a potent inhibitor of active sodium transport, on the amount and composition of bile was studied in the dog. Ten milligrams per kilogram of body weight of furosemide were injected intravenously to anesthetized dogs with a previously constructed fistula of the common bile duct. In all dogs, a 2.5 times increase in bile flow was observed concomitant with a 15 times increase in urinary output. The amount of bile flow decreased gradually and returned to control levels 60 to 75 minutes after furosemide injection. The choleretic effect was associated with a high increase in sodium, chloride and bicarbonate anions and with a smaller increase in potassium, phosphorus and calcium. The total amount of bilirubin alkaline phosphatase and cholesterol was not significantly affected, while the calculated output of inorganic salts increased. The results indicate that inhibition of sodium reabsorption by furosemide simultaneously affects the liver and kidney and that the increase in electrolyte solution is most likely caused by the inhibition of sodium reabsorption in the ductuli. Furosemide also may interfere with the sodium mediated secretory fraction at the canalicular level, but the predominant factor determining the increase in bile flow and electrolytes is inhibition of sodium reabsorption in the biliary ducts and ductuli.


Effect of intraduodenal acid on the pre- and postvagotomy basal gastric secretion and gastrin. Acid instillation into the duodenum inhibits basal and stimulated gastric secretion. In man vagotomy suppresses this secretory inhibition. It is postulated that such inhibition responds to a dual mechanism: an hormonal one (enterogastrone) and a nervous one (vagus nerve). This study showed that preoperative duodenal acidification of duodenal ulcer patients results in a decrease in basal gastric secretion and in gastrin levels. On the contrary, in patients submitted to vagal denervation--either through truncal division or highly selective vagotomy--duodenal acidification does not inhibit gastric secretion; however, a drop occurs in basal gastrin levels. An intact gastric vagal innervation therefore, seems necessary for the preservation of the sensitivity of the parietal cell to the effect of hormonal inhibitors, it being immaterial whether duodenal innervation is present or not, as that duodenal acidification provokes a significant fall in serum gastrin levels as determined by radioimmunoassay. This hormonal decrease produced by duodenal acidification can be explained by the inhibition of gastrin release from the antrum. Agreement is expressed with the opinion of other authors that highly selective vagotomy does not appear to carry any advantage over truncal section of the vagus nerves from the standpoint of the inhibitory mechanism of gastric secretion from the duodenum.


Relationship between the prolongation of warm ischemia and the maximum available preservation period. Fifty dog kidneys had hypothermic perfusion for 12 to 72 hours and then were transplanted. Prior to perfusion the kidneys were subjected to 15, 30, 45, and 60 minutes of warm ischemia. Fifteen minutes of warm ischemia was well tolerated (successful 72 hour preservation), but after 30 minutes successful preservation could be achieved for 24 hours only. Enzyme release and lactate formation were related to the prolongation of warm ischemia, and the highly significant concentration differences of these substances, between well functioning kidneys and those with small or no function, indicated the viability of the organ.


Effect of endotoxin shock on skeletal muscle cell membrane potential. Transmembrane potential changes were monitored in 21 dogs that were shocked by intravenous injectin of Difco purified endotoxin (055:B5). Corresponding serial measurements of electrolyte concentration in plasma and muscle biopsies were obtained to assess fluid and electrolyte changes. During shock the transmembrane potential was found to become significantly less negative (-55.2 mv.) from a control of -87.5 mv. (p less than 0.001). A significant efflux of K+ (p less than 0.02) from the cell was recorded, but intracellular Na+ and Cl- concentration rose. A plausable explanation for the fluid and electrolyte shifts, possibly due to a decrease in the muscle temperature and a resultant decline in metabolism, has been offered.


[Effect of thymus cells on the radiosensitivity and differentiation trends of hematopoietic stem cells]. A stimulating influence of thymus cells on the capability of irradiated (from 100 to 500 r) bone marrow of mice of producing colonies in spleen of syngenous recipient has been proven. The intensification of colony formation involves an increased radioresistance of stem cells. It is supposed that radioresistant thymus cells have a stimulating effect. Thymus cells exert their influence not only to the rate of survival of stem cells proliferating in the bone marrow of femur, but also increase their erythropoetic potention.


Local mechanism of CO2 action of cat pial arterioles. The effect of local hypercapnic acidosis or local hypocapnic alkalosis on pial arterioles were studied in anesthetized cats equipped with a cranial window for the direct observation of the pial microcirculation of the parietal cortex. Changes in PCO2 and pH of the extracellular fluid were induced by perfusing the space under the cranial window with artificial cerebrospinal fluid equilibrated with different concentrations of CO2, while PaCO2 was maintained constant. Hypercapnic acidosis dilated and hypocapnic alkalosis constricted pial arteioles markedly. The results indicate that a basis exists for considering CO2 as a mediator for local regulation of brain blood flow. The vasodilation associated with arterial hypercapnia was abolished by a reduction in CSF PCO2 equal in magnitude to the rise in arterial blood PCO2, suggesting that the action of CO2 is entirely local.


Subclavian steal in Takayasu's arteritis. A hemodynamic study by means of ultrasonic Doppler flowmetry. Blood flow in the vertebral artery and the upper extremity was studied in five cases of Takayasu's arteritis with subclavian steal by use of ultrasonic Doppler flowmetry and finger plethysmography. The diagnosis of subclavian steal was made by observation of flow reversal in the vertebral artery on the subclavian steal side during grip exercise and, in addition, the vertebral flow change with brachial artery occlusion. The blood flow increase of both internal cartotid and non-affected (non-subclavian steal side) vertebral arteries during a common carotid compression was almost normal in patients with Takayasu's arteritis in this study. During carotid compression on the side of the subclavian steal, ipsilateral vertebral blood flow greatly decreased, and the amplitude the ipsilateral finger plethysmogram decreased slightly or moderately. It is suggested that there are significantly important factors in suppressing sumptoms of vertebrobasilar ischemia in these patients with Takayasu's arteritis with subclavian steal. These factors are believed to be (1) good function of the circle of Willis, (2) good blood supply to the brain stem, and (3) collateral circulation to the distal subclavian artery not via the vertebral artery.


Changes in agglomeration of human red blood cells in liquid storage in CPD media. A procedure which may distinguish between old and new CPD blood units in liquid state is described. It is based on the observation of increased tendency to reversible agglomeration in old erythrocytes in liquid preservation. Erythrocytes clump together when they are mixed with low ionic strength solutions in pH range of 5.2 to 6.5. We found that liquid-stored erythrocytes show an augmented tendency to agglomerate in 0.24M sucrose, pH 7.2. The tendency increases with storage so that in the fourth week, more than 70% of the units show agglomeration under these conditions. The addition of minute amounts of sodium chloride may prevent agglomeration. As the cells age, higher salt concentration is required to prevent agglomeration. A short incubation of washed cells with adenosine may reverse the tendency of outdated erythrocytes to agglomerate, concomitantly with reestablishment of initial ATP level. However, depletion of the ATP of fresh cells with fluoride does not induce agglomeration. A 20 hour incubation of units at 37 C with CPD revealed an increased sensitivity of older units, with low ATP and positive agglomeration. This test may help in distinguishing between outdated and younger units in the blood bank.


Renal distal tubular secretory mechanisms in healthy Nigerian subjects. The distal tubular secretory mechanisms of 30 healthy Nigerians were investigated. This entailed the collection of three different 24 hour urine samples; firstly basal values, secondly during the administration of 15 g of NH4Cl and finally when 5 g of KCl was given addition to 15 g NH4Cl. The basal 24 hour urinary volume was 1.36 litres with an average pH of 6.52 containing 42.74 mEq of combined acid and 114.5, 47.6 and 128.4 mEq Na+, K+ and CIce-ions respectively. During ammonium chloride ingestion the 24 hour urinary acid excretion rose to 72.35 mEq whilst the pH fell to 5.71. The values for Na+, K+ and CIce-were 183.2, 51.5 and 245 mEq respectively. When both NH4Cl and KCl were ingested urinary pH rose to 6.38, total acid excretion fell to 48.6 mEq whilst K+ excretion increased considerably to 172.1 mEq. This discussion stresses the point that though the healthy Nigerian may excrete lower values of H+ and K+ ions on the typical low protein diet; the renal distal secretory mechanism can respond appropriately when adequately challenged, as in this investigation.


[Participation of pancreatic ribonuclease in the digestion processes]. The authors purified the alkaline ribonuclease obtained from the pancreas and the contents of the superior part of the dog's intestine. A comparative examination of physico-chemical properties and specificity of the separated enzymes was effected. The resulting data prove the pancreas to be the source of the alkaline ribonuclease contained in the superior portion of the intestine.


[pH measurements in the vascular wall of dogs with electrically induced thrombosis of the femoral artery]. Electrically induced thrombosis is often used for pathophysiologic and therapeutic experiments. The pH value of the vascular wall was measured to approach the features of this thrombosis. After inducing thrombosis by direct current, pH value of the intima of femoral artery was found decreased. The anode was inserted in the lumen. As to the behavior of the pH value, electric thrombosis and clinical thrombosis are similar. Electric thrombosis therefore seems to be valuable for comparing investigations.


[Gas levels and biochemical changes in cerebrospinal fluid after experimental brain injury: its effect on cerebral circulation and cerebral metabolism as well as its management]. 1. After brain damage experimentally induced by balloon compression, liquor of the cistern shows a metabolic acidosis with significantly increased lactate level and L/P quotient, and statistically distinct decrease of pH, oxygen tension, and bicarbonate level. 2. There is a considerable disproportion between the changes of acid-base metabolism, gas tension, and metabolic products in cerebrospinal fluid compared with much less expressed disturbances in the blood. 3. The advanced edematous phase shows distinct accumulation of water in the tissue, considerable increase of intracranial pressure, resp. decrease of effective perfusing pressure, loss of autoregulation, and decreased regional and global cerebral circulation, while the pathologic alterations of cerebral fluid are intensified. 4. Treatment of lactate acidosis in the liquor by intrathecal application of sodium bicarbonate results in improved cerebral circulation and metabolism of the cerebral tissue, having thus a good influence on cerebral damage and its sequels.


[Glucose transport across the mucosa of the small intestine]. The rate of glucose absorption in an isolated loop of the small intestine in rats was measured. The maximum rate of absorption was registered with 3 and 5 per cent concentrations, while 1 and 10 per cent solutions are absorbed at a slower rate. The absorption rate of 5 per cent glucose solution did not materially change for one hour after a sugar load. The small intestine mucosa transports glucose from a 5 per cent solution at an equal rate in rats and rabbits, i. e. 139+/-4 and 143+/-6 gamma/cm2/min. Maximum absorption takes place with pH of 6-8. Deviation of the pH value to acidity and alkalinity is attended by steep fall in the absorption rate. At pH of 3.0 and 11.5 the absorption virtually ceases altogether. Hexobarbital anesthesia depresses absorption of glucose in the intestine by a factor of 2-3.5.


[Fetal heart rate, dip area and acid base observations in breech and vertex deliveries (author's transl)]. Fetal heart rate (FHR), dip area (DA) and the acid base status (AB) were investigated in breech deliveries (BD) (N= 167) and in group of spontaneously delivered vertex presentations (VP) (NFHR, DA=50; NAB=109). 90 minutes prior to delivery fetal heart rate and dip area were in both groups not significantly different. However as labor progressed the fetal heart rate as well as dip area increased in breech deliveries much more (FHR 163 (SD 16.2) beats/min, DA 1,07 (SD 0,80) cm2/min) than in VP (FHR 136 (SD 14,8) beats/min, DA 0,65 (SD 0,39) cm2/min) (2p less than 0,001). The base excess of the umbilical arterial blood was correlated to the DA measured from 10 minutes prior to birth till the delivery of the baby: BE =  -8,2 --0,3 (DA) (2alpha less than 0,01). The frequency of acidotic babies was more in vaginally delivered breech presentations (pH less than 7,20 = 30, 2%, BE greater than -10 meq/l = 43,7%) than in breech deliveries by caesarean section (pH less than 7,20 = 19,1%, BE greater than -10 meq/l = 24,4%) and vertex presentations (pH less than 7,20 - 5,5%, BE greater than -10 meq/l = 14,6%), respectively. The distance between the vertex and the umbilicus was 28 cm and between the breech and the umbilicus 9,4 cm. From this anatomical observation it is concluded that umbilical cord compression, preferentially umbilicai vein occlusion takes place in breech presentation at an earlier point on than in vertex presentation. The rise of fetal heart rate and the increase in dip area are showing in addition that the fetal buffer base in breech presentation will be reduced during the last time course of the second stage of labor.


[Protein hydrolysis by pepsin and trypsin at a varying pH]. The continuity of the pepsin and trysin action on the proteinic substrates with different pH was studied. A short-term incubation of protein with pepsin at high pH intensifies the tryptic effect on this protein, the initial rate of the protein hydrolysis then gains momentum and the possibility of its complete hydrolysis increases over the same period of time. With successive action of fibrin of the gastric and pancreatic secretions prinicipally the same relationship has been established.


Nanoencapsulated fluorescence indicator molecules measuring pH and pO2 down to submicroscopical regions in the basis of the optode-principle. To measure pO2 in gases or fluids and pH in solutions the fluorescence indicators pyrene butyric acid and beta-methylumbelliferone, respectively, were nanoencapsulated to obtain nano-probes for measurement in physiological structures of nano-range. For pH the fluorescence changes of beta-methylumbelliferone were monitored, for pO2 the fluoresence quenching of pyrene butyric acid by oxygen were registered. Drawing log (S1/S2) versus pH, one obtains a straight line between the pH from 6 to 8. A linear increase in pO2 between 0 and 400 torr yields a linear increase in the reciprocal fluorescence signal.


Effects of phospholipids in the action of acetyl-CoA carboxylase from rat liver. Acetyl-CoA carboxylase (E.C. 6.4.1.2) was isolated from rat liver. The purified enzyme contains phospholipids with a rather large amount of phosphatidylinositol (26%). Incubation of the purified acetyl-CoA carboxylase with phospholipase A2 (E.C. 3.1.1.4) or with phospholipase D (E.C. 3.1.1.4) diminishes the phospholipid content by 70%, this treatment leading to a complete inactivation of the enzyme. After removal of the phospholipases, the lipid-depleted enzyme can be reactivated to a certain degree by incubation with a phospholipid extract from rat liver, with phosphatidylinositol alone, or with serum albumin.


The effect Escherichia coli lipopolysaccharide (endotoxin) on the graft-versus-host reaction in mice (IV). Lipopolysaccharide from Escherichia coli (LPS) administered to mice during the graft-versus-host (GvH) reaction in a single dose of 100 mug stimulated the reaction if it was given on the same day as the parental spleen cells, or inhibited it if given four days before injection of the cells. The GvH reaction was intensified when LPS was injected in the dose of 20 mug on the fourth day after injection of the cells. The parental spleen cells responsible for the intestifying effect on GvH were sensitive to hydrocortisone, nonadherent, and probably develop in the course of the first week outside the donor spleen and settle in the spleen in a later stage of the GvH reaction.


Age-dependent resistance of chicken of Salmonella in vitro: antibacterial activity of lysed granule fraction of splenic adherent cells. Lysed granule fraction was prepared from splenic adherent cells from 0-day-old to 2-month-old chickens and was examined antibacterial activity to Salmonella pullorum and Salmonella sentfenberg. The activity of lysed granule fraction from 2-month-old chickens was exhibited at pH 5.0 but not exhibited at pH 6.0 or 7.0 to both serotypes of Salmonella. At pH 5.0, lysed granule fraction from 0-day-old chickens revealed little antibacterial activity to S. pullorum but the activity increased with increasing age. At 240 min of incubation, 60% and 95% of S. pullorum were inactivated in lysed granule fractions from 7-day-old and 2-month-old chickens, respectively. High antibacterial activity to S. senftenberg was observed in lysed granule fraction from 2-month-old chickens in which 99.6% of the bacteria was inactivated during 240 min; In lysed granule fractions from 0-day old and 7-day-old chickens, 90% of S. senftenberg was inactivated during 60 min but the number of bacteria increased conversely after incubation for 240 min. Changes in enzymatic activities of 4 enzymes in the lysed granule fractions from various ages of chickens were examined. beta-Glucronidase increased statistically significantly to 2.4 and 7.6 times from 0-day-old to 7-day-old and 2-month-old chickens, respectively. Acid phosphatase and alkaline phosphatase increased slightly but not significantly different, and enzymatic activity of myeloperoxidase was scarcely detected.


[Pigment Formation by Trichophyton rubrum: Differentiation between T. rubrum and T. mentagrophytes on Serum Albumin Agar (author's transl)]. On serum albumin agar (bovine albumin) with initial pH-values of 5.0-6.0, Trichophyton rubrum showed a yellow pigmentation, and on the same medium with an initial pH-value of 7.0, a red pigmentation. Strains of Trichophyton mentagrophytes have never shown pigmentation until now, The scarce growth (submerged) of T. rubrum on serum albumin agar is associated with a pigment formation that may be used for diagnostic purposes. It could be read within 3-7 days. Serum albumin agar with the initial pH-value of 5.0 was introduced in 1964 for the detection of the strain-specific proteolytic activity of Candida albicans.


[Pathogenic factors in viral diseases of the central nervous system]. The possible immunological significance of the different kinds of cells participating in the inflammatory reaction in cerebrospinal infections is to be considered. Presence of plasma cells and occasional perivenous microglial seams in early stages of the neurotropic virus diseases must be regarded as immunological manifestations. The brainstem nuclei are sites of predilection both in entero- and in arbovirus diseases. The aetiologically different neurotropic virus diseases obtain their individual character from the involvement of certain neurones. Neural pathways are to be taken into consideration mainly for the propagation of enteroviruses, but may have a part also in the propagation of arboviruses. With massive invasion by highly cytopathogenic viruses inflammatory reaction may fail to appear in the immature nervous tissue. Some encephalitides, of both viral and non-viral aetiology, in which the prevalence of plasma cells in the infiltrations bears evidence of an intense immune process, may be interpreted as immunologically determined late diseases.


ATP-ase activity in the odontoblastic layer of rat incisor. Determination with a radiochemical and a colorimetric method. The ATP-splitting enzyme activity in odontoblasts isolated from rat incisors has been studied by means of a radiochemical and a colorimetric micromethod. The results with the two methods were virtually identical. The reaction was linear with time for at least 45 min. The pH optimum was found to be 9.8 independently of the ATP concentration. Maximal substrate saturation occurred at a total ATP concentration of 3 mM. Ca2+ and Mg2+ ions activated ATP degradation. F-ions did not affect the activity at low concentrations, whereas higher concentrations were inhibitory. Na+ and ions were slightly inhibitory. Urea inhibited the enzyme activity at concentrations  above 1.5 M, while EDTA and EGTA were strong inhibitors at very low concentrations. When incubating in the presence of low concentrations of specific inhibitors for nonspecific alkaline phosphatase, levamisole and R8231, about 20% ATP degrading enzyme activity remained. In conclusion it is suggested that there are at least two ATP degrading phosphatases active at alkaline pH.


Characterization of kallikrein from human saliva isolated by use of affinity chromatography. Kallikrein was isolated from paraffin stimulated saliva by use of two steps affinity chromatography. A610-fold purification of the enzyme was achieved by use of Sepharose 4B conjugated with soy bean trypsin inhibitor and pancreatic trypsin inhibitor. The isoelectric point of kallikrein was found to be pH 4.3 and the molecular weight was calculated to be about 38.000 by gel filtration on a AcA44 Ultrogel column. The enzyme had a pH optimum at pH 8.6 using BAEE and TAME as substrates. The michaelis constant for kallikrein on these two substrates was 4.0-10(-4) M and 5.5-10(-4)M. respectively.


Characterization of trypsin-like enzymes from human saliva isolated by use of affinity chromatography. Paraffin-stimulated whole mixed saliva was collected from 6 individuals and pooled. Three trypsin-like enzymes from saliva supernatant and two from the saliva sediment were isolated by use of affinity chromatography on a soybean trypsin inhibitor Sepharose 4 B column. The isoelectric points for these enzymes were pI 8.0, 6.8 and 6.4 from the supernatant and  6.4 and 6.2 from the sediment. The enzymes were characterized with respect to pH-optimum, pH-stability, temperature stability, substrate specificity and influence of metal ions and inhibitors. The Michaelis constants were determined for these enzymes on the substrates BAEE and TAME.


Myxofibrosarcoma. A study of 30 cases.

Myxofibrosarcoma. A study of 30 cases. A series of 30 myxofibrosarcomas is described. These malignant soft tissue tumours are characterized by a mucoid and nodular appearance, a coarse plexiform capillary pattern, and they are mostly seen subcutaneously (26 out of 30) in the extremities (24 out of 30) and trunk (4 out of 30) elderly people. Histochemical studies, comprising staining with Alcian blue and toluidine blue at different pH's with and without preceding digestion with testicular hyaluronidase and with the Scott technique, indicated the presence of hyaluronic acid but not sulphated glycosaminoglycans as chondroitinsulphates. Myxofibrosarcoma is believed to belong to the general category of fibroblastic and histiocytic malignant soft tissue tumours. The median diameter of the tumours was 7 cm. They were divided into 4 grades according to cellularity, cell atypia and mitotic activity. The grade III and IV tumours showed pronounced atypia, often with the bi- and multinucleated giant tumour cells and occasionally with giant cells of Touton's type, suggesting a relationship to malignant fibroxanthoma. All of the patients were treated surgically and one received also pre- and post-operative irradiation. None of the 2 grade I myxofibrosarcomas recurred, while 2 out of 7 grade II tumours, 6 out of 10 grade III tumours, and 7 out of 11 grade IV tumours recurred once and up to 9 times. Metastasis appeared in 7 out of 30 patients; grade I tumours were not seen in any of these cases. By the time of follow-up after intervals ranging from 1 month up to 27 years, 14 patients had died; 6 of these had died post-operatively or of intercurrent disease. The differential diagnosis between myxofibrosarcoma and other myxoid soft tissue tumours is discussed.


Disposition of three benzodiazepines after single oral administration in man. Three benzodiazepines in equipotent doses: oxazepam 15 mg, dipotassium chlorazepate 10 mg and diazepam 5 mg, were administered in single, oral doses to seven healthy volunteers in a three-way cross-over study. The serum concentrations of oxazepam, N-desmethyldiazepam and diazepam were followed for 72 hours by gas chromatography and electron capture detection. The absorption of diazepam was most rapid and the mean time required to reach peak serum concentration was 45 minutes, followed by N-desmethyldiazepam 80 minutes and oxazepam 114 minutes. The serum concentration decay curves were biphasic with terminal mean half-lives of 48, 62 and 11 hours for diazepam, N-desmethyldiazepam and oxazepam, respectively. The mean and individual serum concentration time data were fitted to a two-compartment open model with first order absorption using a non linear least square program. The mean serum data fitted the model well. The same rank order was obtained with mean absorption half-lives as when comparing mean peak times while slightly shorter terminal half-lives were obtained in the curve fitting of mean serum data. Due to irregularities in the serum concentration time curves only five out of the 21 sets of individual data could satisfy the convergence criterion. The obtained parameters in the curve fitting were also accompanied with very large asymptotic standard deviations.


Biological studies on the effects of some therapeutic procedures used in psychiatry. The glucose, lactate, and pyruvate levels, the lactate/pyruvate ratio and pH were studied in serum and CSF of patients with schizophrenia, reactive psychosis, symptomatic or circular psychosis under the effect of atropine coma, ES and pentetrazole convulsions, tranquilizer treatment and combined therapy. Convulsive therapy caused a disorder in cerebral carbohydrate metabolism while no similar changes were induced by atropine coma. Anaerobic carbohydrate metabolism was stimulated by combined therapy. This treatment had the best effect and the changes caused by it were slighter than in the case of convulsive therapy. The changes in EEG frequency corresponded to the biochemical changes.


Solubilization of particle-linked urate oxidase by different agents. Urate oxidase was mostly recovered in a 40 000 g for 20 min subcellular fraction from conventional homogenated. Different agents were able to solubilize the sedimentable enzyme when tested on this crude peroxisomal fraction. The agents increased also total enzyme activity which was recovered in supernatants after centfiguation. If the possible effect of absorption to pellets is to be discounted, the enzyme was practically 100% extracted by six alternated freezing and thawing high alkaline pH, the detergent Hyamine 2389 and high ionic strength of calcium chloride. Triton X-100 was very effective in extracting proteins from the fraction, while it left most of the enzyme activity insoluble. It is suggested that the forces responsible for the integrity of the crystalloid, which was observed by other authors at the electron microscope, and to which the enzyme is believed to be related, are the electrostatic nature.


Effects of acetylsalicylate on alkalinization, acid secretion and electrogenic properties in the isolated gastric mucosa. The effects of acetylsalicylate (ASA) on the in vitro secretory and electrical properties of Necturus and Rana temporaria gastric mucosa have been studied. The gastric antrum alkalinized the luminal surface, while in the fundus it is likely that acidificaiton and alkalinization occur simultaneously and that net secretion is due to the dominance of one or other of these processes. The histamine H2  receptor antagonist Metiamide was used to inhibit acid secretion for studies on fundic alkalinization in Rana temporaria. Submucosal application of 3 mM ASA for 30 min markedly reduced alkalinization in the antrum and the frog fundus. Following removal of ASA there was only partial recovery of this secretion. The drug caused slight inhibtion of spontaneous acid secretion in Necturus fundus but not of histamine-stimulated acid secretion in the frog fundus. Following salicylate removal, the rate of acid secretion increased to a higher level than before administration in both tissues. There was a small flux of ASA across the mucosa which was greatest in the acid secreting frog fundus (4.38mumol cm-2 min-1) and least in the antrum (2.19 mumol cm-2 min-1). Esposure of the gastric mucosa to ASA was generally associated with a fall in transmucosal electric potential difference and short-circuit current together with an increase in electrical resistance. It is proposed that the greater sensitivity of alkalinization to ASA is responsible for the apparent increase in the rate of acid secretion which occured.


Lower body negative pressure and effects of autonomic heart blockade on cardiovascular responses. Heart rate, arterial pressure and cardiac output were recorded in eight healthy male volunteers during exposure to 80 mmHg of lower body negative pressure (LBNP) in the supine position before and after beta-adrenergic and combined beta-adrenergic and parasympathetic blockade of the heart as induced by the i.v. administration of propranolol 0.25 mg/kg b.wt. and atropine 0.04 mg/kg b.wt. After propranolol, heart rate response to LBNP averaged 48% of that observed without blockade indicating that LBNP-induced cardioacceleration is of both sympathetic and parasympathetic origin. Tolerance to LBNP was reduced by beta-adrenergic blockade, since the decrease in mean arterial pressure during LBNP was exaggerated by such blockade. Although the addition of atropine markedly elevated mean arterial pressure and cardiac output in the control situation, tolerance to LBNP was not enhanced by this drug as judged from the arterial pressure response. Post-LBNP overshoot in mean arterial pressure was strikingly augmented by combined cardiac effector blockade and was in part due to a lingering elevation of total peripheral resistance, cardiac output remaining decreased for more than 110 s after release of LBNP.


Partial correction of hypertension by angiotensin II blockade in a patient with phaeochromocytoma. This case report describes a patient with malignant hypertension and phaeochromocytoma in whom blockade of angiotensin II receptors by the competitive antagonist 1-sar-8-ala-angiotensin II (Saralasin) resulted in a partial correction of the elevated BP. Plasma renin activity was high and rose further during the blockade. Competitive inhibition of angiotensin II by Saralasin does not abolish the pressor effect of catecholamines. It was therefore interesting to observe that in this patient with phaeochromocytoma, independently, both alpha-adrenergic receptor blockade and angiotensin II receptor blockade were effective in lowering BP.


Neurochemical evidence for histamine acting as a transmitter in mammalian brain. HA, besides its function in immune processes, is probably a neurotransmitter in mammalian brain. It is synthesized by a specific decarboxylase localized in the cytoplasm of nerve endings. It is stored in synaptic vesicles. Its release might depend on nerve-impulse flow; specific receptors to this amine have been evidenced both electrophysiologically and by the activation of cyclic AMP formation. Lesion studies indicate that histamine-containing neurons might constitute an ascending bundle arising from the brainstem and widely projecting into the whole telencephalon. This disposition, together with neuropharmacological data, suggests that histaminergic neurons, like the monoaminergic ones, might be involved in the control of arousal mechanisms, an idea consistent with the observed fluctuations of the endogenous amine content during the day-night cycle. On the other hand, the investigation of the effect of stress situations on the turnover of HA in brain leads to the conclusion that histaminergic neurons are specifically affected.