Effect of blood transfusion in low birthweight infants. 143 fresh blood transfusions were given to 32 low birthweight babies, 28 of whom had hyaline membrane disease. The arterial or central venous pressure was raised by a blood transfusion if before transfusion the mean arterial pressure was less than 35 mmHg or if the diastolic central venous pressure was less than -- 0-5 mmHg. There was no effect of blood transfusion on pH. It therefore appears either that metabolic acidosis in hyaline membrane disease is not caused by poor peripheral perfusion or that blood transfusion does not increase peripheral blood flow in this condition. The safety of the procedure is assessed.


Effect of glucocorticoids on the hexose monophosphate pathway in human rheumatoid synovial lining cells in vitro and in vivo. Human rheumatoid synovial lining cells have up to four times the capacity to oxidize glucose 6-phosphate, the first step of the hexose monophosphate pathway, as do the nonrheumatoid cells. The reducing equivalents produced by this system have many significant metabolic effects. Exposure of these cells by 10(-5) M prednisolone in vitro, or to 6 mg/day in vivo, causes some depression of this activity in the rheumatoid synovial lining cells; less than this dose of steroid, or the administration of nonsteroidal drugs in vivo, has little or no effect. The depression of activity produced by 6 mg/day does not bring this activity down to the value found in nonrheumatoid synoviocytes.


Release of antral and duodenal gastrin in response to an intestinal meal. In dogs prepared with isolated, innervated antral pouches, intraduodenal perfusion with liver extract at pH 7, with the atrum buffered at pH 7, resulted in a significant release of gastrin selectively from the antrum and from the duodenum. Acidification of the meal to pH 1 abolished both antral and duodenal gastrin release, whereas acidification of the antrum abolished only the antral gastrin response. After antrectomy, liver extract at pH 7 caused a diminished but significant release of duodenal gastrin. These studies provide evidence that an intestinal meal may release (in addition to a specific intestinal phase hormone) gastrin from the intestine, and from antrum, by means of a pH-sensitive mechanism which may involve a humoral agent (enterobombesin?) from the small bowel.


Hydroxylation of 5,5-diphenylhydantoin (phenytoin) by dog liver microsomes. Chang and Glazko in 1972 had reported failure to demonstrate any production from 5-5-diphenylhydantoin (phenytoin, DPH) by dog liver microsomes of either 5-(m-hydroxyphenyl-5-phenylhydantoin (m-HPPH) or 5-(P-hydroxyphenyl-5-phenylhydantoin (p-HPPH), metabolites of DPH  produced by the dog in vivo. We have incubated DPH with 9,000 X g supermatants of dog liver homogenates and with suspensions of separated microsomes with added NADPH generating system, Mg(2+), and nicotinamide and have demonstrated the production of both m-HPPH and p-HPPH. Both metabolities were detected by thin-layer chromatography of extracts of the incubation mixtures. Detection and roughly quantitative measurement of m-HPPH were also accomplished with gas chromatography.


[pH and lactic acid values in the cerebrospinal fluid as a diagnostic aid for differentiating viral and purulent meningoencephalitis]. Concentrations of lactate and pH were determined in the CSF of 20 normal children, 36 with viral meningitis, 16 with purulent meningitis and six with tuberculous meningitis. No differences were found between normal cases and those with viral meningitis. In patients with purulent meningitis concentration of lactate was above 30 mg/100 ml and pH below 7.3. Both determinations allowed differentiation between viral meningitis and purulent meningitis after 48 hr of treatment with antibiotics in 80% of the cases.


[Acid-base status in the blood of domestic pigs during exhausting locomotor stress of small and medium intensity]. Twenty-two fattening pigs were stressed until their rectal temperatures had reached 42 degrees C. The means of stress included walking on moving conveyor belt at ambient temperatures between 22 degrees C and 27 degrees C and relative humidities between 69 and 98%, belt speeds of 0.7 m/s, 1.3 m/s or 0.7 m/s, and stimulation by means of a forcing rod. Rectal temperature, respiratory frequency, lactic acid level in blood plasma, pH, as well as pCO2 and base excess in the blood were measured prior to, during, and after stressing. Gasping was strongly pronounced due to severe alkalisis, but it was somewhat mitigated on running on the belt with exposure to additional stress on account of lactic acid accumulation in the plasma.


Monoamine metabolite levels in cerebrospinal fluid of psychotic women treated with melperone or thiothixene. Psychotic women with schizophrenic symptoms were treated with melperone 100 mg X 3 (n = 29) or thiothixene 10 mg X 3 (N = 34) USING A DOUBLE-BLIND PROCEDURE. Before and during treatment, levels of HVA, MOPEG, and 5-HIAA, the major metabolites of DA, NE, and 5-HT, were determined in lumbar cerebrospinal fluid by a mass fragmentographic technique. Both treatments resulted in an elevation of the HVA levels after 2 weeks, thiothixene having a more marked effect. The effect of thiothixene but not of melperone persisted after 4 weeks. Thiothixene did not influence the MOPEG level, but melperone reduced it after 4 weeks of treatment. The 5-HIAA levels were not significantly altered by the drugs. The HVA/MOPEG and the HVA/5-HIAA ratios were highly significantly elevated by both drugs after 2 as well as 4 weeks. Thiothixene induced a significantly greater change of these ratios than melperone. The results supply evidence that thiothixene accelerates central dopamine metabolism in man, presumably by blocking DA receptors. Melperone appears to act similarly, but has an effect which is weaker and/or of shorter duration. During long-term treatment with melperone the receptors develop tolerance to it. The acceleration in DA metabolism declines and the effect of melperone switches instead to central NA metabolism. The results indicate that both drugs cause long-term changes in the activity ratios of central monoamine systems. It is suggested that such changes in several systems rather than single biochemical events may be related to the antipsychotic effects of neuroleptic drugs. This study also demonstrated the versatility of using monoamine metabolite analysis of the CSF as a tool for the quantification of biochemical effects of neuroleptic drugs on the human CNS.


Adult cryptorchids: Sexual development and activity. Plasma testosterone in 72 unilateral and 83 bilateral cryptorchids, 11-45 years of age, revealed that, from 13 years on , values of male hormone were lower than in the control group of 69 normal boys and 85 fertile and potent men. Analysis of heterosexual development by means of the HTDM questionnaire in 49 unilateral and 57 bilateral cryptorchids, aged 21-40 years, who were examined for sterility, revealed only slight social developmental retardation compared to 184 normospermic men from sterile marriages. On the other hand, examination of sexual activity by means of the SAM questionnaire in the same three groups revealed that in cryptorchids the first ejaculation is slightly later and that the frequency of nocturnal emissions in pubescence is lower. In adulthood the patients with cryptorchidism exhibit fewer signs of high sexual activity suca as repeated coitus on the same day or a high frequency of sexual intercourse. Also, there is an earlier appearance of prolonged periods of sexual abstinence.


[Ultrastructure of B-cell tumors of the pancreas (insulinomas - insular carcinoid tumors)]. The subcellular organization of 6 B-cell tumours of the human pancreas was studied. The tumour parenchyma consisted of processed light, dark, and moderately electron dense cells containing insulin granules. The presence of villi in the cytoplasm of tumour cells and intranuclear fibrills was demonstrated. The participation of tumour cells in formation of amyloid-like thin-fiber substance filling the intercellular and perivascular spaces was established. The similarity between endothelial cells of tumour vessels and parenchymatous cells was shown. A hypothesis on neuroectodermal origin of the endocrine tissue of the pancreas is supported.


Polyarteritis nodosa and deafness. A human temporal bone study. Temporal bone changes were described in a 66 year old woman with polyarteritis nodosa who became deaf 7 months before death. Polyarteritis nodosa of the left internal auditory artery was demonstrated with fibrosis and bone formation involving the cochlea and vestibular system. Endolymphatic hydrops of the basal turn of the cochlea was also present, as well as a chronic perforation of the free wall of the saccule.


Biochemical and genetic factors in the heat inactivation of murine beta-glucuronidase. The enzymes coded for by two alleles at the glucuronidase structural locus (Gus) were compared in their response to pH, buffering anion, buffer molarity, ionic strength, and temperature. The heat-labile Gush gene product responded in a qualitatively similar but quantitatively reduced manner compared to the relatively heat-stable Gusb gene product. In all buffers tested, the enzyme was most heat stable at pH 5.0. Ranking of the various buffer anions tested, according to increasing heat stabilization, was water less than acetate less than or equal to phosphate less than citrate. Varying the molarity of the buffers from 0.01 to 0.6 M at pH 5.0 revealed further differences among the buffers. Increasing ionic strength exerted a destabilizing force on the protein. The half-life of the enzyme decreased by as much as a hundredfold between 71 and 75 C. The Gush/Gush genotype also results in decreased activity levels in all tissues, reportedly because of decreased synthesis. The heat inactivation curves of Gusb/Gush heterozygotes were incompatible with any theoretical curve based on the assumption that the Gusb and Gush chromosomes in the heterozygote behave in a manner similar to that seen in the homozygotes.


Studies on the female sterile mutant rudimentary of Drosophila melanogaster. II. An analysis of aspartate transcarbamylase and dihydroorotase activities in wild-type and rudimentary strains. The activities of the enzymes aspartate transcarbamylase (ATCase) and dihydroorotase (DHOase) were determined in adult females from a wild-type strain and from eight different alleles of the X-linked mutation rudimentary (r) of Drosophila melanogaster. The alleles chosen span the genetic map of the r locus. The characteristics of the DHOase-catalyzed reaction which converts carbamyl aspartate to dehydroorotate are briefly described. Of all of the r strains tested, only one, r9, has wild-type levels of aspartate transcarbamylase and dihydroorotase activities. The other seven show either intermediate or very low levels of activity for both enzymes. The lowered ATCase and DHOase activities observed in mutants which do not map in the region of the structural gene for these enzymes are interpreted in light of recent evidence that ATCase and DHOase are part of a three-enzyme complex.


Properties of soluble somatostatin-binding protein. A soluble somatostatin-binding protein was detected in the cytosol fractions of various rat, human and bovine tissues. Maximum binding occurred at pH8.0-8.5 and was Ca(2+)-dependent. The specific binding of somatostatin per 10mug of cytosol protein from 12 rat tissues ranged between 36 and 15%, and 3% for peripheral blood cells. There was also substantial binding in cytosol from human anterior pituitary and liver, and bovine anterior pituitary. The specific binding in rat and human plasma in the presence of EDTA was only 1%. Gel filtration suggested a molecular weight of approx. 80000 for the somatostatin-binding protein from several sources. Exposure of the binding protein to trypsin eliminates somatostatin-binding activity but ribonuclease and deoxyribonuclease have no effect. The binding protein is thermolabile, ethanol-precipitable, and not completely specific for somatostatin. Bound (125)I-labelled [Tyr(1)]somatostatin is not easily displaced by excess of unlabelled somatostatin. The effects of dithiothreitol and mercaptoethanol on the binding of (125)I-labelled [Tyr(1)]somatostatin to the binding protein suggests that binding involves two sequential steps, first loose binding, then disulphide linkage. Since semipurified somatostatin-binding protein causes a dose-related inhibition of the binding of (125)I-labelled [Tyr(1)]somatostatin in radioimmunoassays for somatostatin, estimates of somatostatin content of tissue extracts by radioimmunoassay in some cases may be spuriously high. It is not yet clear whether the binding protein is a true cytosol protein or an easily solubilized membrane protein.


Microbial metabolism of aromatic nitriles. Enzymology of C-N cleavage by Nocardia sp. (Rhodochrous group) N.C.I.B. 11216. 1. An organism utilizing benzonitrile as sole carbon and nitrogen source was isolated by the enrichment-culture technique and identified as a Nocardia sp. of the rhodochrous group. 2. Respiration studies indicate that nitrile degradation proceeds through benzoic acid and catechol. 3. Cell-free extracts of benzonitrile-grown cells contain an enzyme that catalyses the conversion of benzonitrile directly into benzoic acid without intermediate formation of benzamide. 4. This nitrilase enzyme was purified by DEAE-cellulose chromatography and gel filtration on Sephadex G-100 in the presence and absence of substrate. The purity of the enzyme was confirmed by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis and isoelectric focusing on polyacrylamide gel. 5. The enzyme shows a time-dependent substrate-activation process in which the substrate catalyses the association of inactive subunits of mol.wt. 45000 to form the polymeric 12-unit active enzyme of mol.wt. 560000. The time required for complete association is highly dependent on the concentration of the enzyme, temperature and pH. 6. The associated enzyme has a pH optimum of 8.0 and K(m) with benzonitrile as substrate of 4mm. The activation energy of the reaction as deduced from the Arrhenius plot is 51.8kJ/mol. 7. Enzyme activity is inhibited by thiol-specific reagents and several metal ions. 8. Studies with different substrates indicate that the nitrilase is specific for nitrile groups directly attached to the benzene ring. Various substituents in the ring are compatible with activity, though ortho-substitution, except by fluorine, renders the nitrile invulnerable to attack. 9. The environmental implications of these findings and the possible significance of the enzyme in the regulation of metabolism are discussed.


Kinetic properties of a magnesium ion- and calcium ion-stimulated adenosine triphosphatase from the outer-membrane fraction of rat spleen mitochondria. 1. Isolated outer membranes from rat spleen mitochondria can be stored in liquid N(2) for several weeks without significant loss of ATPase (adenosine triphosphatase) activity. 2. The ATPase reaction has a broad pH optimum centering on neutral pH, with little significant activity above pH9.0 or below pH5.5. 3. A sigmoidal response of the ATPase activity to temperature is observed between 0 and 55 degrees C, with complete inactivation at 60 degrees C. The Arrhenius plot shows that the activation energy above the transition temperature (22 degrees C) (E(a)=144kJ/mol) is one-third of that calculated for below the transition temperature (E'(a)=408kJ/mol). 4. The outer-membrane ATPase (K(m) for MgATP=50mum) is inactive unless Mg(2+) is added, whereas the inner-membrane ATPase (K(m) for ATP=11mum) is active without added Mg(2+) unless the mitochondria have been depleted of all endogenous Mg(2+) (by using ionophore A23187). 5. The substrate for the outer-membrane ATPase is a bivalent metal ion-nucleoside triphosphate complex in which Mg(2+) (K(m)=50mum) can be replaced effectively by Ca(2+) (K(m)=6.7mum) or Mn(2+), and ATP by ITP. Cu(2+), Co(2+), Sr(2+), Ba(2+), Ni(2+), Cd(2+) and Zn(2+) support very little ATP hydrolysis. 6. Univalent metal ions (Na(+), K(+), Rb(+), Cs(+) and NH(4) (+), but not Li(+)) stimulate the MgATPase activity (<10%) at low concentrations (50mm), but, except for K(+), are slightly inhibitory (20-30%) at higher concentrations (500mm). 7. The Mg(2+)-stimulated ATPase activity is significantly inhibited by Cu(2+) (K(i)=90mum), Ni(2+) (K(i)=510mum), Zn(2+) (K(i)=680mum) and Co(2+) (K(i)=1020mum), but not by Mg(2+), Ca(2+), Ba(2+) or Sr(2+). 8. The outer-membrane ATPase is insensitive to the inhibitors oligomycin, NN'-dicyclohexylcarbodiimide, NaN(3), ouabain and thiol-specific reagents. A significant inhibition is observed at high concentrations of AgNO(3) (0.5mm) and NaF (10mm). 9. The activity towards MgATP is competitively inhibited by the product MgADP (K(i)=0.7mm) but not by the second product P(i) or by 5'-AMP.


Evidence for two-step binding of reduced nicotinamide-adenine dinucleotide to aldehyde dehydrogenase. The displacement of NADH from cytoplasmic aldehyde dehydrogenase (EC 1.2.1.3) from sheep liver was studied by using NAD+, 1,10-phenanthroline, ADP-ribose, deamino-NAD+ and pyridine-3-aldehyde-adenine dinucleotide as displacing agents, by following the decrease in fluorescence as a function of time. The data obtained could be fitted by assuming two first-order processes were occurring, a faster process with an apparent rate constant of 0.85 +/- 0.20 s-1 and a relative amplitude of 60 +/- 10% and a slower process with an apparent rate constant of 0.20 +/- 0.05 s-1 and a relative amplitude of 40 +/- 10% (except for pyridine-3-aldehyde-adenine dinucleotide, where the apparent rate constant for the slow process was 0.05 s-1). The displacement rates did not change significantly when the pH was varied from 6.0 to 9.0. Kinetic data are also reported for the dependence of the rate of binding of NADH to the enzyme on the total concentration of NADH. Detailed arguments are presented based on the isolation and purification procedures, the equilibrium coenzyme-binding studies and the kinetic data, which lead to the following model for the release of NADH from the enzyme: (formula: see article). The parameters that best fit the data are: k + 1 = 0.2 s-1; k - 1 = 0.05 s-1; k + 2 = 0.8 s-1 and k - 2 = 5 X 10(5)litre-mol-1-s-1. The slow phase of the NADH release is similar to the steady-state turnover number for substrates such as acetaldehyde and propionaldehyde and appears to contribute significantly to the limitation of the steady-state rate.


Purification and some properties of 1-aspartamido-beta-N-acetylglucosamine amidohydrolase from human liver. Human liver 1-aspartamido-beta-N-acetylglucosamine amidohydrolase (aspartylglucosylaminase, EC 3.5.1.26) was purified 17 500-fold to apparent homogeneity as judged from polyacrylamide-gel disc electrophoresis. A pH optimum of 7.7-9.0 was found. The Km value was pH- and temperature-dependent. At 37 degrees C and pH 7.7, Km was 0.16 mM and it increased to 0.29 at pH 6.0 and 0.23 at pH 9.0. At 25 degrees C and pH 7.7, a Km value of 0.99 mM was obtained. When the substrate concentration was varied, apparent Michaelis-Menten kinetics were obtained. p-Hydroxymercuribenzoate, glutathione or cysteine had no effect on the enzyme activity; 5 mM-N-acetylcysteine inhibited about 47% of the total enzyme activity. Apart from Cu2+, other bivalent ions were virtually ineffective at 1 mM. The kinetic study differentiates this enzyme from aspartylglucosylaminase from other sources.


Effect of substrates and effectors on the reversible inactivation of pig spleen phosphofructokinase by adenosine triphosphate. 1. To investigate the mechanism of the reversible inactivation of pig spleen phosphofructokinase by ATP, the effect of order of addition of reactants (substrates, effectors and enzyme solution) was studied by preincubating the enzyme before assay with various combinations of its substrates and effectors. 2. Preincubation of the enzyme with MgATP or ATP at pH7.0 before addition of fructose 6-phosphate caused a rapid and much greater inhibition of activity than that observed when the reaction (carried out at identical substrate concentrations) was initiated with enzyme. 3. The rapid inhibition caused by preincubation with ATP, together with the sigmoidal response to fructose 6-phosphate and activation by AMP, were all blocked by prior photo-oxidation of the enzyme with Methylene Blue, which selectively destroys the inhibitory binding site for ATP [Ahlfors & Mansour (1969) J. Biol. Chem.244, 1247-1251]. 4. Fructose 6-phosphate, but not Mg(2+), protected phosphofructokinase from inhibition during preincubation with ATP in a manner that was sigmoidally dependent on the fructose 6-phosphate concentration. 5. Mg(2+), by protecting the enzyme from the inhibitory effect of preincubation at low pH (7.0) and by preventing its activation during preincubation with fructose 6-phosphate, demonstrated both a weak activating effect in the absence of the other substrates and a stronger inhibitory effect in the presence of fructose 6-phosphate. 6. Positive effectors (K(+), NH(4) (+), AMP and aspartate) protected the enzyme from inhibition during preincubation with MgATP in proportion to their potency as activators, but citrate potentiated the ATP inhibition. P(i) significantly slowed the inactivation process without itself acting as a positive effector. 7. The non-linear dependence of the initial rate of the unmodified enzyme on protein concentration (associated with increased positive homotropic co-operativity to fructose 6-phosphate) was intensified by preincubation with ATP and abolished by photo-oxidation. 8. The results are interpreted in terms of an association-dissociation model which postulates that protonation, at low pH, of a photo-oxidation-sensitive inhibitory site for ATP allows more rapid dissociation of an active tetramer to an inactive dimeric species.


[Synthesis and physico-chemical properties of the antihypertensive agent urapidil (author's transl)]. 6-(3-[4-(o-Methoxyphenyl)-1-piperazinyl]-propylamino)-1,3-dimethyluracil (Urapidil, Ebrantil) is a new antihypertensive agent whose synthesis and physico-chemical properties are described. The size of the permeation constant KD of the passive transport through collodion-lecithin membranes and the value of the partition coefficient P in the neutral area indicate a good absorption and uniform distribution of the substance in the organism.


Effect of dihydroergotoxine on activities of beta-receptor stimulators. The effect of dihydroergotoxine (DET), an alpha-receptor blocker, on the bronchodilating effect of various beta-receptor stimulators was examined using the isolated guinea-pig tracheal smooth muscle. Relaxation of isolated guinea-pig tracheal smooth muscle with isoproterenol hydrochloride, salbutamol hemisulfate and clorprenaline hydrochloride, was markedly increased by continous infusion of DET. This result may suggest that DET, an alpha-receptor blocker, can be used together with bronchodilators such as beta-receptor stimulator for the treatment of various chronic obstructive pulmonary diseases.


A study of antidepressant activity of some indole alkylamines. The antidepressant characteristics of three indole alkylamines were investigated and compared with phenelzine and imipramine by utilising specific pharmacological tools like reserpine, amphetamine, tryptamine and tetrabenazine for determining their possible mechanism of action. Amongst the three indole compounds investigated, indole-3-(2-aminopropyl)-acetate (U-14 164E), indole-3(2-aminobutyl)-d-acetate (u-17 312E) and beta-phenethylhydrazine (phenelzine) produced complete antagonism to reserpine induced sedation, hypothermia as well as facilitation of convulsive seizures. Some of these features suggest that MAO inhibition might be a common mechanism of action of these indoles. The potentiation of CNS effects of tryptamine by these compounds is an outstanding feature of MAO inhibitors, while imipramine is ineffective. Qualitative differences between these indoles and imipramine are evident in the tetrabenazine test. The potentiation of amphetamine induced motor excitation and pentobarbitone narcosis has been explained.


Bioavailability of quinidine in slow-release form. A comparison between two preparations containing quinidine bisulphate as the active constituent. Two different slow-release preparations of quinidine bisulphate (A and B) have been tested. The in vitro dissolution rate of preparation B was substantially lower in intestinal than in gastric juice, whereas the release rate of quinidine from preparation A was virtually unaffected by the pH of the dissolution medium. After a single dose of two tablets of each of the preparations to 6 healthy volunteers, corresponding to 386 mg (B) and 320 mg of quinidine base (A), the maximum plasma concentration was attained after about 4.5 h. The peak concentration was 5.2 +/- 0.5 mumol/l for preparation A and 4.1 +/- 0.4 mumol/l for B. A similar difference was found in the area under the plasma concentration curve (AUC), which was 68 +/- 10 mumol-h/l and 54 +/- 5 mumol-h/l, respectively. Taking into consideration that preparation B contained 20.6% more active drug per tablet these values indicate that the extent of bioavailability is about 50% higher for tablet A than for tablet B.


Flunitrazepam compared with althesin as an induction agent in balanced anaesthesia. The effects of flunitrazepam and Althesin as anaesthetic induction agents were studied in a double-blind trial in 97 patients undergoing abdominal or gynaecological surgery. There was no difference between the two preparations in respect of the quality of induction. A marked difference in the quality of maintenance of anaesthesia were seen, in favour of flunitrazepam. Recovery was more rapid from Althesin anaesthesia. A low incidence of nausea was observed in both groups.


Studies of drugs given before anaesthesia XXVI: lorazepam. Lorazepam has been studied as preanaesthetic medication given by mouth, i.m. and i.v. Sediation and side-effects and the incidence of anterograde amnesia in patients having a standard operation under methohexitone-nitrous oxide-oxygen anaesthesia were assessed. In a preliminary study of three i.m. (2-, 4- and 8-mg) and six oral (1-,2-,2.5-,4-,5- and 8-mg) doses, the optimum dose was found to be 4 mg for patients with an average weight of 60 kg. This dose was studied in detail when given by all three routes and compared with the commercially available 2.5- and 5-mg tablets. Even when given i.v., there was a delay of 30-40 min in the onset of maximum sedative effect and drowsiness persisted for at least 4 h. Although the onset of action by i.m. injection was slightly faster than when the drug was given by mouth this advantage was more than offset by the high frequencies of pain at the site of injection and restlessness which persisted for 20-40 min. Oral lorazepam in doses of 2.5-5.0 mg was a reliable, effective sedative which could be recommended for routine preanaesthetic medication, provided rapid recovery was not essential. Its soporific effect was accompanied by an appreciable incidence of anterograde amnesia.


Substrate and substrate analogue binding properties of Renilla luciferase. Luciferase from the anthozoan coelenterate Renilla reniformis catalyzes the oxidative decarboxylation of luciferin consuming 1 mol of O2 per mol of luciferin oxidized and producing 1 mol of CO2, 1 mol of oxyluciferin, and light (lambdaB, 480 nm) with a 5.5% quantum yield. In this work we have examined the binding characteristics of luciferin, luciferin analogues, and competitive inhibitors of the luciferin-luciferase reaction. The results show that luciferin binding and orientation in the single luciferin binding site of luciferase are highly specific for and dependent upon the three group substituents of the luciferin molecule while the imidazolone-pyrazine nucleus of luciferin is not directly involved in binding. Anaerobic luciferin binding promotes a rapid concentration-dependent aggregation of luciferase which results in irreversible inactivation of the enzyme. This aggregation phenomenon is not observed upon binding of oxyluciferin, luciferyl sulfate, or luciferin analogues in which the substituent at the 2 position of the imidazolone-pyrazine ring has been substantially altered.


Pyridoxamine-pyruvate transaminase. 1. Determination of the active site stoichiometry and the pH dependence of the dissociation constant for 5'-deoxypyridoxal. Spectrophotometric titration of pyridoxamine-pyruvate transaminase (EC 2.6.1.30) with pyridoxal at pH 7.15 gives four equivalent binding sites per tetramer. The pH dependence of the equilibrium constant for the association of 5'-deoxypyridoxal with the active site lysine residue was determined spectrophotometrically. These dissociation constants increase with increasing pH over the range pH 7.5-9 and are correlated with the values obtained from fast reactions kinetics (Gilmer, P. J., and Kirsch, J. F. (1977), Biochemistry 16 (following paper in this issue)). In addition to this specific reaction at an active site lysine residue, a second slower reaction at non-active site residues is observable at pH values greater than 8. The pH dependencies of the association and dissociation rate constants for this slow reaction were studied over the pH range 8 to 9 after blocking the active site by NaBH4 reduction of the pyridoxal adduct. The enzyme is stabilized and markedly activated by potassium ion.


Isoelectric focus analysis of rat anti-phosphocholine antibodies. Anti-phosphocholine (PC) antibodies in sera from four strains of rats were examined before and afterimmunization with either Streptococcus pneumoniae R36A, which contains PC as a cell wall component, or with PC-coupled keyhole limpet hemocyanin (PC-KLH). PC-specific protein was purified from pooled immune sera and shown by a combination of isoelectric focus (IEF) in acrylamide and crossed immunoelectrophoresis, as well as by molecular weight determination in NaDodSO4-acrylamide, to be immunoglobulin. An additional, small molecular weight, nonimmunoglobulin protein (pI = 7.1-7.3) was present in sera from normal and germ-free rats which had the ability to bind the C-carbohydrate of S. pneumoniae R36A, but without specificity for PC. The IEF profile of normal and immune sera showed marked sharing of bands of anti-PC antibody between individual rats as well as between strains. In addition, other anti-PC antibodies which focused between pH 8.5 and 9.5 were less regularly shared. The uniformity of IEF profile of the bulk of anti-PC antibodies in rats is most consistent with their being the products of germ line genes.


Interaction of oligoribocytidylates with T7 DNA in neutral and acid media. Oligoribocytidylates of chain length 4 to 12 were found to interact with native T7 DNA at neutral and slightly acid pH. The results suggest that binding occurred at deoxycytosine clusters which may be displaced by the oligomers at neutral pH, while a local triple-stranded structure would be formed at acid pH. Transcription of DNA-(Cp)n complexes by Escherichia coli RNA polymerase showed a decrease in level without affecting the specificity of the transcription, suggesting that oligocytidylate binding did not occur on the promoters.


Rabbit liver transglutaminase: physical, chemical, and catalytic properties. Transglutaminase (R-glutaminyl-peptide:amine alpha-glutamyl-yltransferase [EC 2.3.2.13]) has been purified to apparent homogeneity from extracts of rabbit liver. The enzyme is a single polypeptide chain of approximately 80 000 molecular weight containing one catalytic site per molecule. That the isolated enzyme is the rabbit counterpart of the well-characterized guinea pig liver transglutaminase is evidenced by the similarities in their amino acid compositions and in their enzymic activities toward several substrates, together with the fact that the isolated rabbit enzyme is immunologically distinct from both rabbit plasma and rabbit platelet blood coagulation factor XIII. A striking difference between the catalytic activities of the rabbit and guinea pig enzymes is the low activity of rabbit transglutaminase for hydroxylamine incorporation into benzyloxycarbonyl-L-glutaminylglycine, a reaction for which the guinea pig enzyme shows a high reactivity. This finding reveals the cause of error in an earlier report (Tyler, H.M., and Laki, K. (1967) Biochemistry 6, 3259) that rabbit liver contains little, if any, of the enzyme. Preparation of, and analytical data on, several glutamine-containing peptide derivatives used in this study are reported here.


Classification and localization of hemoglobin binding sites on the red blood cell membrane. The binding of hemoglobin to the red cell membrane was characterized over a wide range of free hemoglobin concentrations by measurement of membrane bound and supernatant hemoglobin. Scatchard analysis of the binding data revealed two classes of sites: high affinity sites with a binding constant of 1 X 10(8) M-1 and 1.2 X 10(6) sites per cell, and a second, low affinity class of sites with a binding constant of 6 X 10(6)M-1 and 6 X 10(6) sites per cell. The low affinity sites are shown to be nonspecific and appear to be a result of the ghost preparation. The high affinity sites are shown to be specific to the inner surface of the red cell membrane. The competition of hemoglobin and glyceraldehyde-3-phosphate dehydrogenase suggests band III proteins as a potential binding site for hemoglobin.


A change in the internal affinity of LK goat red-cell sodium pumps induced by high pH. The K inhibition of ouabain-sensitive ATPase activity of LK goat red cell membranes is greatly reduced at high pH. This effect is reversible, and specific, since the apparent affinities for ATP, ouabain or external K do not alter. Anti-L-treated membranes show a similar alkali-induced affinity change, but have a lower pH optimum.


Counter-transport mediated by the lactose permease of Escherichia coli. When the two main energy yielding pathways, respiration and the membrane ATPase of Escherichia coli are poisoned, the lactose permease is unable to accomplish accumulative transport of thiogalactosides, but the efflux of preloaded substrate can be coupled to a transiently uphill transport of exogenous substrate. This transient uphill transport, called overshoot has been reexamined with the possibility of an obligate H+ cotransport in mind. Overshoot can be diminished but not suppressed by a proton-conducting uncoupler, carbonyl cyanide m chlorophenylhydrazone, (CCCP) and by a liposoluble cation, triphenyl-methyl phosphonium (TPMP+). The effect of other factors, such as temperature, amount of permease and pH were also explored. The overshoot was found to decrease with increasing pH, until at pH 8 it became negligible. This is in sharp contrast with the relatively flat pH dependence of uphill and downhill transport in unpoisoned cells. CCCP and TPMP+ had no inhibitory effect on the overshoot at pH 6 and below.


Fractionation of membrane vesicles. II. A method for separation of membrane vesicles bearing different enzymes by free-flow electrophoresis. Free-flow electrophoresis was used to subfractionate membrane vesicles from calf thymocyte plasma membranes. The fractionation resulted in a separation of vesicle populations bearing four different enzymes: alkaline nitrophenyl-phosphatase (orthophosphoric-monoester phosphohydrolase (alkalin optimum) EC 3.1.3.1), gamma-glutamyltransferase (EC 2.3.2.2), (Mg2+ + Na+ + K+)-ATPase (ATP phosphohydrolase, EC 3.6.1.3) and acyl-CoA:lysophosphatidylcholine acyltransferase (acyl-CoA:1-acylglycero-3-phosphocholine-O-acyltransferase, EC 2.3.1.23). The specific content of cholesterol and total phospholipid coincided with the distribution of membrane-bound protein. However, vesicles migrating towards the cathode had a higher molar ratio of cholesterol to phospholipid (0.75) compared to those migrating to the anode (0.55). Sodium dodecyl sulphate-gel electrophoresis of pooled vesicle fractions also demonstrates distinct differences in their protein pattern. Electron-micrographic thin sections show that the vesicle populations have a similar morphology and size distribution. These results are discussed in terms of heterogeneity of the original thymocytes, contamination with intracellular membranes and a heterogeneous structure of the plasma membrane.


Permeability of amino acids into liposomes. 1. A simple and rapid assay for the measurement of permeability of amino acids into liposome membrane was carried out by using the liposomes trapping D-amino acid oxidase (D-amino acid: O2 oxidoreductase (deaminating), EC 1.4.3.3) inside the membrane. 2. Permeability of amino acids into liposomes depended on the lipid composition of the membrane. Permeability of amino acids into phosphatidylcholine-cholesterol liposomes depended critically on temperature. 3. Permeability also depended on the structure of amino acids. The order of permeability was norvaline greater than isoleucine greater than leucine greater than phenylalanine greater than tryptophan greater than methionine greater than tyrosine, valine greater than threonine greater than serine greater than alanine greater than glycine.


Effects of pH on the properties of normal and 5-fluorouracil-containing tRNAs. Transfer RNAs isolated from Escherichia coli B grown in the presence of 5-fluorouracil (FIUra) show variations in their aminoacylation levels when compared with normal samples. Some of these variations result from the more stringent aminoacylation reaction conditions required for FIUra-tRNAs. Increasing the reaction pH from 7 to 9 for example, generally causes a lowering of amino acid acceptance by the analog-containing tRNAs, while leaving control samples largely unchanged. This decreased activity appears to result primarily from fluorouracil ionization, which in turn disrupts intramolecular hydrogen bonding and promotes an overall increase in the molecular dimensions of FIUra-tRNAs at elevated pH values. Sensitivity to pH differes with the amino acid examined, with lysine showing dramatic changes and glutamine and proline being largely unaffected.


Properties of D(+)-lysopine dehydrogenase from crown gall tumour tissue. D(+)-Lysopine dehydrogenase of an octopine-type Crown Gall tumour has been partially purified and a number of kinetic parameters have been determined. D(+)-Lysopine dehydrogenase catalyzes the reductive condensation of pyruvate and one of at least six different L-amino acids, as well as the reverse reactions, with preferential use of NADP(H) as a cofactor. The optimal pH for both reductive and oxidative reactions has been determined. At pH 6.8, L-lysine has of all the amino acids the lowest Km value, while at the same pH the highest V was found with L-arginine and L-histidine. The isoelectric point of D(+)-lysopine dehydrogenase is about 4.5.


Coordinate and non-coordinate accululation of aspartate transcarbamylase and dihydroorotase in synchronous Chlorella cells growing on different nitrogen sources. Regulation of the levels of aspartate transcarbamylase (carbamoylphosphate:L-aspartate carbamoyltransferase, EC 2.1.3.2) and dihydroorotase (L-5,6-dihydro-orotate amidohydrolase, EC 3.5.2.3) was studied in synchronous cultures of the eucaryotic microorganism Chlorella. Analytical polyacrylamide gel electrophoresis and sucrose density-gradient centrifugation studies revealed that these cells contain a single aspartate transcarbamylase and a dihydroorotase with apparent molecular weights of 160 000 and 80 000, respectively. In synchronous cells cultured in nitrate medium, these two enzymes accumulated in single step-patterns over different periods of the cell cycle. In contrast, these enzymes accumulated in a coordinate manner throughout the cell cycle in ammonium medium. Experiments with inhibitors of protein and RNA synthesis indicated that dihydroorotase is stable in vivo and suggested that cell cycle changes in the turnover rate of aspartate transcarbamylase might determine whether or not these enzymes accumulate in a coordinate manner. Although uracil and uridine could be absorbed and metabolized by the cells, synthesis of these two enzymes could not be repressed by culturing synchronous cells in medium, containing high concentrations (29-40 mM) of uracil or uridine, for an entire cell cycle.


Characterization of the aspartate carbamoyltransferase fragment generated by protease action on the pyrimidine-3 gene product of Neurospora crassa. The molecular weight of the fragment of aspartate carbamoyltransferase (carbamoylphosphate: L-aspartate carbamoyltransferase, EC 2.1.3.2) of Neurospora crassa following proteolysis was found to be 1.0-10(5) (aspartate carbamoyltransferase-L). It differs from the native form of the enzyme (aspartate carbamoyltransferase-N, 6.5-10(5)) in several respects. It has a lower V, has a much greater affinity (approx. 3-fold) for L-aspartate, and is strongly activated by glycine. Both forms of aspartate carbamyoltransferase have a pH optimum of approx. 9.5, and they exhibit similar affinities for carbamoyl phosphate.


Differential stabilities of soil enzymes. Assay and properties of phosphatase and arylsulphatase. Methods have been refined for the assay of phosphatase and arylsulphatase activities in soil, based on the chromogenic p-nitrophenyl ester substrates. Basic assay conditions have been defined, and pH optima and kinetic parameters have been determined. The enzymes follow Michaelis-Menten kinetics; this conclusion is based on three methods of analysis of data determined over a wide range of substrate concentrations. The enzyme activities are very stable to storage of wet soil for up to 4 weeks at soil temperatures and above. For example, phosphatase had a half-life of approximately 2 weeks at 50 degrees C; arylsulphatase was rather less stable. Both enzymes retained 80% of activity after incubation with pronase for 1 week at 25 degrees C. On the basis of this work and studies on other soil enzymes, it is concluded that remarkable stability is a general feature of soil enzymes.


Purification of an acid proteinase from Aspergillus saitoi and determination of peptide bond specificity. The specificity and mode of action of an acid proteinase (EC 3.4.23.6) from Aspergillus saitoi were investigated with oxidized B-chain of insulin, angiotensin II and bradykinin. Further purification of acid proteinase was performed with N,O-dibenzyloxycarbonyl-tyrosine hexamethylene-diamino-Sepharose 4B affinity chromatography and isoelectric focusing. The purified enzyme was free of any other proteolytic activity demonstrated in Asp. saitoi. Acid proteinase from Asp. saitoi hydrolyzed primarily two peptide bonds in the oxidized B-chain of insulin, the Leu(15)-Tyr(16) bond and the Phe(24)-Phe(25) bond. Additional cleavages of the bonds His(10)-Leu(11), Ala(14)-Leu(15) and Tyr(16)-Leu(17) were also noted. Primary splitting sites at Leu(15)-Tyr(16) and Phe(24-)-Phe(25) with acid proteinase from Asp. saitoi were identical with those reported in the work of cathepsin D (EC 3.4.23.5) from human erythrocyte. Hydrolysis of angiotensin II was observed at the Tyr(4)-Ile(5) bond. In conclusion, peptide bonds which have a hydrophobic amino acid such as phenylalanine, tyrosine, leucine and isoleucine in the P'1 position (as defined by Berger and Schechter, [29]) are preferentially cleaved by the trypsinogenactivating acid proteinase from Asp. saitoi.


Purification of the tyrosine inhibitable 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase from Schizosaccharomyces pombe. A method is described for the purification of the tyrosine inhibitable isoenzyme 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase (7-phospho-2-keto-3-deoxy-D-arabino-heptonate D-erythrose-4-phosphate-lyase(pyruvate phosphorylating), EC 4.1.2.15) to homogeneity as judged by polyacrylamide gel electrophoresis.


The effect of an NADPH-regenerating system on biphenyl metabolism in isolated rat hepatocytes. Biphenyl 4-hydroxylation was studied in isolated rat hepatocytes. It was found that there was in inter-relationship between 4-hydroxylase activity and glucuronidase activity, removal of 4-hydroxybiphenyl by conjugation being necessary to stimulate a second phase of hydroxylation. Addition of an NADPH-regenerating system resulted in an initial depression of both processes, but later their activities were enhanced. This action could not be explained by the presence of non-viable cells.


Relationship between intramitochondrial citrate and the activity of carbamoyl-phosphate synthase (ammonia). The possibility of control of the activity of carbamoyl-phosphate synthase (ammonia) (EC 2.7.2.5) in rat-liver mitochondria by variation in the intramitochondrial free Mg2+ concentration has been investigated. Carbamoyl-phosphate synthase activity was measured by coupling the formation of carbamoylphosphate to the synthesis of citrulline in a reaction mixture containing ammonia, bicarbonate, a source of ATP, and ornithine. The synthesis of citrulline was inhibited by lowering the concentration of intramitochondrial free Mg2+. This could be achieved not only by depleting the mitochondria of Mg2+ (by adding the ionophore A23187), but also by increasing the intramitochondrial concentration of citrate. Under various conditions an inverse relationship between the rate of citrulline synthesis and the magnitude of the intramitochondrial concentration of citrate was observed. Inhibition of citrulline synthesis by intramitochondrial citrate could be partly reversed by addition of Mg2+ in the presence of A23187. Possible implications of the regulation of carbamoyl-phosphate synthase (ammonia) activity by intramitochondrial citrate for nitrogen metabolism in the liver are discussed.


Lectins in the hemolymph of Japanese horseshoe crab, tachypleus tridentatus. The hemolymph of the Japanese horseshoe crab, Tachypleus tridentatus contains lectins which agglutinate mammalian erythrocytes. Affinity chromatographic purification of the lectins using bovine submaxillary gland mucin-conjugated Sepharose resulted in the separation of the lectins into four fractions; one major and three minor lectins. Protein subunits revealed by polyacrylamide gel electrophoresis and the immunoprecipitin line of these lectins against antiserum to crude lectins were unique to each fraction. The activities of all the lectins were optimal at pH values between 6 and 8, and were destroyed by heating at 60 degrees C. Calcium chloride augumented the activities of three lectins, but the major lectin was not influenced by the salt. Bovine erythrocytes were not agglutinated by any of the lectins and comparative agglutination titers for other erythrocytes from various sources were different among these lectins. The activities of all the lectins were inhibited by N-acetylamino sugars. They were more effectively inhibited by glycoproteins which contain sialic acid.


Coordination-chemistry study of polypeptides. III. protonation-deprotonation equilibrium study of synthetic alphaH -corticotropin1-32. Data on the pH-dependent conformation of corticotropin. By potentiometric equilibrium measurements and the computer evaluation of experimental data, the protonation equilibrium constants of four fragments of corticotropin (ACTH), ACTH1-32. ACTH1-28, ACTH1-14 and ACTH1-4, were determined and assigned to the corresponding functional groups. From the dependence of the protonation constants on the length of the peptide chain, it was established which functional groups participate in the formation of intramolecular hydrogen-bonds in aqueous solutions at various pH. These results indicated a pH-dependent conformation of the molecule.


[Studies of basic proteins of 60S- and 40S-subunits of pea seed ribosomes by two-dimensional polyacrylamide gel electrophoresis]. Basic proteins of 60S- and 40S-subunits of pea seed ribosomes were studied by two-dimensional electrophoresis in polyacrylamide gel (PAAG) with subsequent electrophoresis of separated proteins in the gels containing sodium dodecyl sulfate. The proteins under study were found to be electrophoretically heterogenous and showed considerable variations in the staining by amido black and a specific distribution between the two subunits. 47 protein components were detected in the protein preparations of the 60S subunit: 18--as intensively stained, 12--as moderately stained and 17--as weakly stained spots. Presumably, the 60S subunit does not contain proteins whose molecular weights are over 60.000 or below 14.000. Two proteins have mol. weight over 50.000; other proteins have mol. weights varying between 15.000 and 30.000. 32 proteins components were revealed in the protein preparations of the 40S subunit: 15--as intensively coloured, 8--as moderately coloured and 9--as weakly coloured spots. The 40S subunit does not contain proteins whose molecular weights are over 33.000 and below 10.000. Three proteins have mol. weights over 30.000, the other proteins have mol. weights within the interval of 15.000--30.000. The amount of basic proteins in the 80S plant ribosomes is, in all probability, higher as compared to that in animal ribosomes, and this is due to the 60S subunit.


Recent developments in the biochemistry of globoid and metachromatic leucodystrophies. Galactosylceramides and their sulphates are the main constituents of myelin sheath of the nerve cell. Two genetically determined disorders are the results of an inability to enzymatically hydrolyse these glycolipids. Thus the deficiency of galactosylceramide beta-galactosidase results in globoid cell leucodystrophy and the reduced activity of enzyme, arylsulphatase A is responsible for the disease Metachromatic leucodystrophy. Both these disorders are fatal and are characterized by marked demyelination and severe mental retardation. Since homognenous enzyme preparations of galactosylceramide beta-galactosidase and arylsulphatase A are now available, a possibility of enzyme replacement therapy in globoid and metachromatic leucodystrophies has been discussed.


In-vitro and in-vivo properties of canine blood mononuclear leukocytes separated by discontinuous albumin density gradient centrifugation. Dogs were given 1 200 R whole body x-irradiation and transfused with frozen and thawed mononuclear leukocytes from a DLA identical, MLC negative donor dog. These leukocytes had been obtained from the peripheral blood by means of leukapheresis, using the IBM experimental cell separator after injection of 15 mg/kg body weight of dextran sulphate to increase the yield of CFUc upon collection. The segregation of leukocytes by means of the discontinuous albumin gradient centrifugation method resulted in a fraction 2 that contained a very high proportion of CFUc, and in other fractions 3 and 4 with a high proportion of lymphocytes with few CFUc. The dog receiving fraction-2 cells showed a rapid bone marrow recovery (permanent) and displayed no signs of gvh-reaction. The dogs receiving cells of fraction 3 or 4 died of gvh-reaction within 25 days. The dog receiving fraction 4 cells showed little hemopoietic recovery, but a marked lymph node hyperplasia of plasma cells.


Local anesthetics. Effect of pH on use-dependent block of sodium channels in frog muscle. Sodium currents were studied under voltage clamp in the presence of neutral, amine, and quaternary local anesthetic compounds. Use-dependent block was observed as a cumulative depression of INa seen with repetitive depolarizing test pulses applied at frequencies of 2-10s-1. With quaternary QX-314, the time constant of use dependence was long, and with neutral benzocaine, very short. With lidocaine and procaine, increasing external pH (pHo) changed the time constant from long to short, but alterations of internal pH have no effect. Inactivation in Na channels was measured by the influence of prepulses on peak INa during test pulses. Single-stimulus inactivation curves were shifted more with lidocaine at high pHo than at low pHo, but inactivation curves measured during pulse trains with any of the drugs and at any pHo were strongly shifted. All measurements show that the drug-receptor reaction was slow for amine drugs at low pHo, as for quaternary drugs at any pHo, and fast for amine drugs at high pHo, as for neutral drugs at any pHo. The major effect of low pHo on amine drugs was to reduce the concentration of drugs in the fiber and to protonate drug molecules on the receptor, thus trapping them in the blocking position for a longer time. Direct effects of pH on the receptor seemed minimal.


The effect of acid pH on the growth kinetics of Trichoderma viride. Batch cultures of Trichoderma viride have been carried out in a 10 liter stirred fermenter a controlled pH values of 2.5, 2.7, 3.0, and 4.0 and without pH control at a temperature of 28 degrees C. Cell and glucose concentrations and dissolved oxygen values are reported. The yield coefficient was found to be constant at 0.40 kg cells/kg glucose and the maximum specific growth rate was linearly correlated with the hydrogen ion concentration.


Preparation and properties of immobilized papain and lipase. Papain and lipase were immobilized on derivatized Sepharose 4-B. The activated agarose had a binding capacity of 1.2 micronmol amino groups/ml packed agarose or 17 mg proteins/g dry agarose. The immobilized enzyme preparations were tested for the effects of pH of assay, temperature of assay, and substrate concentrations. The effect of 6M urea on the activity of papain was also determined. Soluble forms of the enzymes were used for comparison. Immobilization of the enzymes resulted in slightly different pH and temperature optima for activities. For immobilized papain Km(app) was similar to the one observed with soluble papain. Immobilization of lipase, however, cause a decrease in Km values. The immobilized enzyme preparations were stable when stored at 4 degrees C and pH 7.5 for periods up to eight months. The soluble enzymes lost their activity within 96 hr under similar storage conditions. Immobilized papain did not lose any activity after treatment with 6M urea for 270 min, whereas soluble papain lost 81% of its activity after the urea treatment, indicating that the immobilization of papain imparted structural and conformational stability to this enzyme.


Development of hematopoietic spleen colonies in nonirradiated genetically normal mice. The question as to whether prior irradiation or injection of cytotoxic drugs is essential for the development of spleen colonies was examined in genetically normal mice. Mixtures of lymph node and bone marrow cells from C57BL mice were injected into (C57BL X CBA-T6T6) F1 hybrid mice without pretreatment. Hematopoietic nodules were observed in the spleens of F1 hybrid mice killed 18 days after injection. The average number of nodules increased linearly with increased numbers of injected bone marrow cells. Hematopoietic stem cells (CFU-S) and dividing cells in the nodules were shown to be of C57BL origin. Histologic examination showed that erythroid cell colonies predominated over granulocytic cell colonies. These results suggest that any kind of treatment that causes the depletion of CFU-S in the spleen of hosts would provide a suitable environment for the production of colonies by transplanted CFU-S.


Further studies of sulphasalazine metabolism in the treatment of ulcerative colitis. Sixty-four outpatients with ulcerative colitis receiving maintenance treatment with sulphasalazine were studied to relate disease activity to serum concentrations of sulphapyridine. Of 43 patients in remission, 32 had serum sulphapyridine levels over 20 microgram/ml. Ten of the 21 patients with active disease were for various reasons taking inadequate doses of sulphasalazine, as indicated by low serum sulphapyridine levels, and of the remaining 11 patients, who had serum levels over 20 microgram/ml, nine had faecal stasis proximal to active distal colitis and went into remission when treated with hydrophilic colloid or bran and an unchanged sulphasalazine dosage. This suggests that to be effective the metabolites of sulphasalazine must be delivered in the faeces to the lumen of the diseased distal segment of the colon. High serum concentrations of sulphapyridine produce side effects; therefore slow acetylators of sulphapyridine need lower doses of sulphasalazine. Estimations of serum sulphapyridine concentrations, as well as identifying the patient's acetylation phenotype, can also be useful in assessing his compliance with treatment.


Quinonoid dihydropterin reductase from beef liver. Quinonoid dihydropterin reductase has been purified from beef liver. This enzyme has been shown to be indistinguishable from the reductase of sheep liver in molecular weight, subunit composition, and terminal residues. Both beef and sheep liver reductases possess acyl isoleucine as the N-terminal residue. Use of improved isolation techniques, including general ligand affinity chromatography, has yielded enzyme preparations of much higher specific activity than previously reported. Affinity chromatography experiments also suggest that the enzymic reaction proceeds by a compulsory ordered mechanism.


Isolation and properties of a glycerophosphate acylating fraction in the fat body of Schistocerca gregaria (Forskäl). An acyl-CoA-L-alpha-glycerophosphate acyltransferase system has been found in the fat body of the locust Schistocerca gregaria (Forskäl). After homogenization and differential centrifugation the enzyme system has been localized in two distinct particulate fractions. In both fractions phosphatidic acid was the main reaction product. The 10 000 g -30 000 g particulate fraction was further studied. The enzyme system is very sensitive to pH and Mg2+ concentration. An apparent Km of 0.3-0.5 mM for glycerophosphate was measured. The substrate concentration curve for palmitoyl-CoA is influenced by the protein concentration in the assay medium. This effect would partly explain the non-lineariy of the acylation reactions with respect to enzyme concentration. These observations are correlated with physiological phenomena.


Heterogeneity of alkaline ribonuclease in the mouse and Ehrlich ascites cells. The specific activity of alkaline RNase II was l00 to 1800 times higher in mouse pancreas than in mouse liver, serum, ascites fluid, and Ehrlich ascites cell grown intraperitoneally. Ehrlich ascites cells grown in cell culture medium had a much lower alkaline RNase II activity than cells grown intraperitoneally. Chromatography on CM-52 cellulose of acid- and heat-treated preparations showned a considerable heterogeneity of the mouse enzymes. Depending on the source of the extract, two to six forms fo alkaline RNase were eluted. Pancreatic extract contained two RNase forms. These also seemed to be present as minor components in preparations from other sources except Ehrlich ascites cells grown in vitro. Ehrlich ascites cells grown in vivo contained forms of the RNase which were not present in other extracts. Possible reasons for this heterogeneity were investigated. In addition to their stability to acid and heat the different RNase forms were similar in that they were much more active at alkaline pH than at acidic pH, they did not require divalent metal ions for activity, and they degraded RNA 'endonucleolytically.' Also, native DNA, denatured DNA, and poly A were poor substrates compared with RNA. Some differences seemed to exist, however, with respect to their abilities to degrade poly U and poly C and their sensitivities to the endogenous RNase inhibitor.


An analysis of the action of lanthanum on aortic tissue from normotensive and spontaneously hypertensive rats. Significant tension development resulting from the administration of lanthanum salts (La3+) to isolated aorta tissues was observed in preparations from the spontaneously hypertensive rat (SHR) but not in preparation from age-matched normotensive Wistar rats (NWR). The response to La3+ was significantly greater in tissues maintained in bicarbonate-buffered Krebs than observed in bicarbonate and phosphate-free HEPES-buffered Krebs. At least part of the LA3+ response in the bicarbonate- and phosphate-buffered solutions was due to a pH shift and could be mimicked by raising the extracellular hydrogen ion [H+] concentration. However, a direct action of La3+ on excitation-contraction coupling could be observed in HEPES-buffered solutions where the addition of La3+ also resulted in tension development but no significant pH change; this action of La3+ was found to be resistant to inhibition by maintenance in a Ca2+-free medium and (or) D-600 pretreatment suggesting an intracellular action for La3+. The paradoxical response to both H+ and La3+ in the SHR aorta suggests that the muscle membrane may be more permeable to these ions and, in addition, suggests that the membrane and (or) intracellular calcium stores in this tissue may also be more labile than those in the normotensive controls.


Role of transmitters in mediating hypothalamic control of electrolyte excretion. Changes in urinary volume and electrolyte excretion were monitored after the injection of cholinergic and monoaminergic drugs into the third cerebral ventricle of conscious male rats made diuretic by an intravenous infusion of 5% dextrose. A natriuretic and kaliuretic response was induced by the intraventricular injection of norephrine (NE) or carbachol, whereas dopamine (DA) had no effect. The beta-receptor stimulator isoproterenol (ISO) induced an antinatriuretic and antikaliuretic effect. Intraventricular injection of the alpha-adrenergic blocker phentolamine abolished the natriuretic response to NE and carbachol and to intraventricular hypertonic saline (HS). By contrast, the beta-adrenergic blocker propranolol induced a natriuresis and kaliuresis when injected alone and an additive effect when its injection was followed by NE or HS. Propranolol potentiated the natriuretic response to carbachol. Cholinergic blockade with atropine diminished the response to NE and blocked the natriuretic response to HS. It is suggested that sodium receptors in the ventricular wall can modify renal sodium excretion via a stimulatory pathway involving cholinergic and alpha-adrenergic receptors and can inhibit sodium excretion via a tonically active beta-receptor pathway.


Bile-salt-dependent and independent choleresis induced by bucolome in the rat. Choleresis induced by bucolome (BC) (1-cyclohexyl-5-n-butyl-2,4,6-trioxoperhydropyrimidine) was studied in male Wistar rats. [14C]Erythritol and mannitol clearance studies indicated this choleresis to be of canalicular origin. In 1-h continuous bile collection studies, immediately after the interruption of enterohepatic circulation (acute interruption), both bile flow and bile salt excretion rates were significantly increased in rats administered BC. However, the bile salt excretion rate fell rather rapidly in BC-administered rats, while the bile flow rate was fairly constant during this 1-h period. Thus, unlike the situation in control rats, bile flow rate was not significantly correlated with the bile salt excretion rate in BC-administered rats. In rats that had an external bile fistula open for 16-20 h (chronic interruption of enterohepatic circulation) the bile flow rate was also significantly increased by BC administration, while the bile salt excretion rate was not changed after BC administration. It is suggested that BC induced bile-salt-independent choleresis in both experimental rat groups (acute and chronic interruption of enterohepatic circulation). In addition, BC appeared to increase the bile-salt-dependent fraction of bile in rats with acute interruption of enterohepatic circulation, possibly by mobilizing the bile salt pooled in the intestinal content and (or) intestinal wall.


Regulation of pyruvate kinases from Fusarium oxysporum. Two types of pyruvate kinases were found in Fusarium oxysporum. One type (inducible) was present mainly during the early stages of growth on glucose or sucrose and displayed Michaelis-Menten kinetics with respect to phosphoenolpyruvate and adenosine diphosphate. The major type (constitutive) was present under all conditions of growth and displayed in the absence of potassium ions, a sigmoidal substrate saturation curve when phosphoenolpyruvate was used as the variable substrate. In the presence of potassium ions the saturation curve for phosphoenolpyruvate exhibits a plateau at half-maximal velocity. The effects of various metabolites on the activity of the inducible and constitutive kinases were also studied. Fructose-1,6-diphosphate, cyclic AMP, acetyl CoA, tryptophan, and phenylalanine had no effect on the activity of the enzymes. Citrate was a potent inhibitor of the constitutive pyruvate kinase activity and increased the sigmoidicity of the saturation curve for phosphoenolpyruvic acid. In the presence of K+, the bimodal plot observed in the absence of citrate gradually changed to a hyperbolic shape as the concentration of citric acid was increased. In the presence of K+ and ADP as the variable substrate citric acid converted the hyperbolic plot to a sigmoidal one. Citrate had no effect on the inducible enzyme.


The effect of different nitrogen sources on pigment production and sporulation of Monascus species in submerged, shaken culture. Thirty-nine strains from the genus Monascus were cultivated aerobically to study the relation between nitrogen nutrition and sporulation and pigment production. The effects of yeast extract, nitrate, ammonium, and ammonium nitrate have been compared. During cultivation the pHs of the different media are not the same, resulting in the formation of different coloured pigments. When the source of nitrogen is yeast extract or nitrate the pH is around 6.5 and red pigments are formed, whereas with ammonium or ammonium nitrate the pH is around 2.5 and the pigments are orange. It is proposed that only the orange pigments, monascorubrin and rubropunctatin, are produced biosynthetically and that the other pigments are formed from these by chemical transformations depending on the cultural conditions. The presence of organic nitrogen is optimal for growth and unfavourable for pigment production. Reduced growth and best pigment formation occurs with the three other nitrogen sources. Nitrate stimulates conidiation and sexual reproduction, while ammonium is inhibitory. Pigment production is better when conidiation is reduced. A mechanism is proposed for the control of sporulation and pigment production.


Physiological and biochemical studies on senescing tap root nodules of soybeans. Senescence of soybean (Glycine max L. Merr.) tap root nodules was investigated by comparing changes in various physiological and biochemical activities with changes in capacity to fix nitrogen. Field-grown Beeson  and Calland varieties of soybeans of various ages were sources of tap root nodules. With both varieties, the number of tap root nodules per plant remained constant between 56 and 86 days after planting but fresh weight, dry weight, and mass of tap root nodules increased duing this period. Nitrogen (C2H2)fixation by attached tap root nodules was maximum on a fresh weight, dry weight, or nitrogen basis about 56 days after planting for either variety. Metabolic activities of bacteroids as measured by carbon dioxide evolution from glucose and succinate did not appear to vary among nodules of different ages. There was also no indication of mobilization or deposition or deposition of iron, molybdenum, calcium, zinc, and nitrate in aging tap root nodules. Nitrate levels in the aerial portion of the plants decreased significantly after the initial decline in acetylene reduction. Nicotinamide deamidase activity in the cytosol and in extracts of bacteroids did not change significantly as tap root nodules aged. However, significant and consistent changes were observed in initial pH values of nodule breis and the initial decline occurred before (Calland) or concurrently (Beeson) with the initial decline of nitrogen fixation.


Influence of acetohydroxamic acid on experimental Corynebacterium renale pyelonephritis. The role of Corynebacterium renale urease in the establishment of pyelonephritis was studied by the oral administration of acetohydroxamic acid (AHA), a urease inhibitor, to experimentally infected rats. The bacteria were introduced by surgical insertion of a zinc disc containing 1 X 10(6) colony-forming units of C-renale into the urinary bladder whereas sterile discs were implanted in the bladders of the control animals. Daily administration of AHA via the drinking water did not halt the development of pyelonephritis. Larger doses, given by gavage, did accomplish this goal; that is, the pH of the urine was lowered, the number of colony-forming units of C. renale in the kidney was reduced drastically, and pyelonephritic lesions were observed in the kidney by light-microscopic examination. All experimental rats developed cystitis in varying degrees of severity. About 70% of the intact AHA given by gavage was excreted in the urine 24 h after administration of this compound. Rats implanted with a urease-negative mutant of C. renale displayed no signs of pyelonephritis but did develop cystitis.


Metabolism of mandelic acid by Neurospora crassa. Preliminary studies on the metabolism of manelic acid by Neurospora crassa reveal the operation of a pathway for its degradation which involves benzoyl formic acid, benzaldehyde, benzoic acid, 4-hydroxybenzoic acid, and protocatechuic acid as the intermediates. This pathway is different from the followed by bacterial systems and is the same as that observed in Aspergillus niger.


The identification of individuals at high risk for large bowel cancer: an overview. Attempts to identify individuals with increased susceptibility to colon cancer before clinical manifestations of disease, have recently been made. Early stages of abnormal growth of colonic epithelial cells, and related factors that may contribute to the development of colonic neoplasia have been shown. Based on the identification of early findings, programs to prevent the evolution of malignancy in individuals at increased risk are under consideration at the present time.


Activation of the guanylate cyclase-guanosine 3'5' monophosphate system of colonic mucosa by n-methyl-n'-nitro-n-nitrosoguanidine. The effects of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) on the guanylate cyclase (GC)-guanosine 3'5' monophosphate (cGMP) system of rat colonic mucosa were studied. MNNG (1 mM) increased colonic mucosal cGMP from 1.8 +/- 0.2 to 22.5 +/- 2.7 pmol/mg protein in 5 minutes. Increases in response to MNNG occurred in the presence or absence of extracellular Ca2+, whereas the two-fold increase in mucosal cGMP mediated by carbamylcholine was abolished by exclusion of Ca2+. Although GC activity of mucosal homogenates was found predominantly (90%) in the 100,000 g particulate fraction, the effects of MNNG on mucosal cGMP correlated with stimulation of 100,000 g soluble GC by this agonist. MNNG increased soluble GC 13-fold over the corresponding basal with 4 mM Mn2+, and 48-fold with 4 mM Mg2+ as the sole available divalent cation. Compared with unstimulated GC, the MNNG-activated soluble enzyme was less dependent upon Mn2+ availability and effectively utilized Mg2+ as metal co-factor. N-ethylmaleimide, a sulfhydryl group alkylator, inhibited MNNG stimulation of GC and cGMP. Thus, expression of these MNNG actions may involve drug interaction with tissue thiol groups. Prior incubation of MNNG with thiol antioxidants or ascorbate also suppressed MNNG stimulation of GC, possibly through direct drug reactions involving nucleophilic and electrophilic reactants. The ability of MNNG to stimulate the colonic mucosal GC-cGMP system could be linked to its carcinogenic action.


Phospholipases A1 and A2 in subcellular fractions and plasma membranes of Krebs II ascites cells. A method is described for the localization and characterization of phospholipases A1 and A2 (EC3.1.1.4) in Krebs II ascites cells, particularly in the plasma membranes. Cells were lysed with a Dounce homogenizer in an isotonic sucrose medium. Plasma membranes sediment with mitochondria and lysosomes during subcellular fractionation and are finally isolated on a continuous sucrose gradient. The membranes are localized at two levels in the gradient, at densities of 1.06 and 1.15, in which 5'-nucleotidase (EC 3.1.3.5) activity exhibits a 9- and 21-fold purification, respectively. Total contamination by endoplasmic reticulum, lysosomes, and mitochondria is 17 percent for the low-density membrane fraction and 25 percent for the high-density fraction. The phospholipases A present in Krebs II cells are active at pH 4.0 and pH 7.5. At the 2 pH values, they have A1 and A2 specificities. The intracellular distribution of acidic forms is comparable to that of acid phosphatase (EC 3.1.3.1), while neutral forms are localized like lactate dehydrogenase (EC 1.1.1.27). A small proportion of neutral phospholipase A2 has the same repartition on the sucrose gradient as nicotinamide adenine dinucleotide diaphorase (EF 1.6.4.3), an endoplasmic reticulum marker, and as 5'-nucleotidase, a plasma membrane marker.


Selective tumor DNA synthesis inhibition: in vivo prodrug activation by an exogenous enzyme. Using the combination of alpha-L-arabinofuranosidase from Aspergillus niger with beta-peltatin A-alpha-L-arabinofuranoside, the selective effect of a new cancer of chemotherapy method based on a pH-dependent activation of cancerostatic prodrugs by exogenous enzymes was studied. In comparative experiments the selectivity of prodrug activation was measured by 3H-thymidine incorporation in tumor and normal tissues of CBA mice inoculated im with the transplantable mammary carcinoma, MA-21224. The results show that this special type of carrier principle may lead to a higher degree of selectivity than the usual direct application of cancerostatic drugs.


Evidence for new catecholamines or related amino acids in some invertebrate sensory neurons. In certain sensory neurons of many different invertebrate species, including the sea anemones. Metridium senile and Tealia felina and the crustacean Artemia salina, fluorophores are formed during the course of the fluorescent histochemical technique of Falck-Hillarp. The presumed catecholamine nature of the neuronal fluorogenic compound was investigated by microspectrofluorometry, and the spectral characteristics of the fluorescence in the taxonomically different species was found to be very similar (excitation maximum at 375 nm with a smaller peak or shoulder at 330 nm and sometimes a shoulder in the spectrum at 410 nm; emission maximum at 475 nm). The emission maximum coincides with that of the catecholamines and DOPA (475 nm). The excitation maximum (375 nm) directly after formaldehyde treatment, however- differs from that of the catecholamines and DOPA (410 nm), but is similar to the excitation maximum displayed by these catechol derivatives at acid pH. The spectral characteristics of the fluorophore in the sensory cells might therefore theoretically be explained by an acid pH in the cells. This means improbable, however, and it is suggested that the phenomenon is due to the presence of unknown catechol derivatives. Analyses of the pH-dependent spectral changes indicate that the presumed catechol derivative in Tealia felina is beta-hydroxylated, whereas that in Artemia salina is not.


The induction of sister chromatid exchanges by cyclophosphamide in the presence of differently induced microsomal fractions of rat liver. The induction of sister chromatid exchanges can be monitored by a test that incorporates the factor of metabolic activation in a simple manner. The results with cyclophosphamide show that in this test the induction of the metabolizing enzymes of the rat liver homogenates used is very important. 3-Methylcholanthrene induces little if any extra conversion of cyclophosphamide to SCE-inducing metabolites, compared with no induction. Aroclor 1254 and phenobarbital however, were very good inducers. The difference found between the liver homogenates concerning SCE induction corresponded with the differences in cyclophosphamide metabolism, which was measured as the decrease in NADPH induced by cyclophosphamide.


[A gas chromatographic study of the composition of neutral and amino sugars in two neuraminidases, of bacterial and viral origin]. The neutral and aminosugar composition has been determined by gas-liquid chromatography for two neuraminidases, either bacterial, from Streptococcus pneumoniae, or viral, from Myxovirus influenzae A/Hong Kong/1/68.


[Action of toxins isolated from scorpion and sea anemone venoms on ileum isolated from reserpine-treated guinea pigs]. We have shown that the ileum isolated from a reserpinized guinea Pig does respond to toxin II obtained from Scorpion venom but does not react to Anemonia sulcata toxin. We conclude that if Acetylcholine is the neurotransmitter inducing pharmacological activity of Scorpion toxin it is serotonin which triggers activity of Anemonia sulcata toxin in ileum of a normal guinea Pig.


Lysosomal and ATP changes after renal-stalk clamping in rats. I. Protective action of Trasylol. The action of Trasylol on the lysosomal and ATP changes after renal-stalk clamping in rats was examined. It was found that, in the presence of an effective Trasylol concentration, a distinct stabilization of the lysosomal membrane can be detected after 30 min of renal-stalk clamping. It was also found that there is only an indirect relationship between lysosomal changes and ATP metabolism under the action of Trasylol. The more rapid regeneration of the ATP is a result of the better microcirculation. The results confirm the earlier belief that Trasylol acts primarily on the lysosomal membrane.


Humoral factors in shock causing bradycardia and myocardial depression. Hypovolemic shock was maintained for 6 hours in dogs in which the heart was hemodynamically protected by a biological model described earlier. Blood of these dogs was exchanged with that of healthy dogs in which myocardial tension and heart rate were continuously monitored. It was found that rate and force of decline in the recipient dog in a fashion similar to the drop in the animal in shock. If, however, the pH of the infused blood was raised to normal, the bradycardia in the recipient dog was prevented but the myocardial depression was not abolished. Administration of aprotinin alone did not prevent the bradycardia or depression of contractility, whereas correction of the pH and treatment with aprotinin not only prevented the decline in both but led also to a transient increase in myocardial tension of the recipient animal. The results seem to indicate that 1) in shock myocardial depression and cardiac slowing are induced by humoral factors transferable by blood to a normal animal, 2) acidity caused the bradycardia but not drop of tension, 3) aprotinin prevents the depression of contractility only in a normal pH medium, and 4) aprotinin may prevent the action of a preformed myocardial depressant factor rather than inhibit its formation.


A possible change in the rate-limiting step for cardiac norepinephrine synthesis in the cardiomyopathic Syrian hamster. The development of heart failure in the cardiomyopathic hamster is associated with a decrease in norepinephrine stores and parallel increases in cardiac sympathetic tone and tyrosine hydroxylase activity. Despite the increase in tyrosine hydroxylase, cardiac norepinephrine synthesis does not increase in heart failure. In this study, we have shown that an accumulation of cardiac dopamine accompanies the decline of cardiac norepinephrine. The abnormal content of norepinephrine and of dopamine in the decompensating hamster heart is restored to normal by peripheral ganglionic blockade. The acute increase in cardiac sympathetic tone induced by immobilization stress in control hamsters mimics the alterations in cardiac catecholamine distribution found in heart failure. Other investigators have demonstrated similar alterations in the catecholamine content of the rat submaxillary gland and adrenal medulla following an increase in sympathetic input to these organs. We conclude that the increase in cardiac sympathetic tone in the late stages of hamster cardiomyopathy appears to lead to a shift in the rate-limiting step for norepinephrine synthesis from the hydroxylation of tyrosine to the hydroxylation of dopamine. There is evidence that this shift which results in an accumulation of dopamine in the noradrenergic nerve terminals of the heart is a general manifestaion of augmented sympathetic nerve traffic rather than a peculiarity of hamster cardiomyopathy.


Natural history and classification of occlusive thromboaortopathy (Takayasu's disease). Fifty-four Japanese patients with occlusive thromboaortopathy (OTAP), including four males, were classified according to evidence of complications attributed to OTAP at the time when the diagnosis was established: Group I, uncomplicated OTAP with or without the involvement of the pulmonary artery. Group II, mono-complicated OTAP: presence of a single complication together with uncomplicated OTAP. Group II was subdivided according to severity into group IIa - mild or moderate form, and group IIb - severe form. Group III, multi-complicated OTAP with two or more complications as well as uncomplicated OTAP. The five-year survival rate after established diagnosis was 83.1%. Seven patients died of OTAP within five years, but all had belonged to group IIb or III.


Effectiveness of an outpatient urine screening program. We evaluated the effectiveness of a routine outpatient urinalysis screening program on a sample population of 2600 patients. The 189 abnormal urine results found in 182 patients were followed up by study of any new clinical and laboratory investigations or therapeutic modifications initiated on the basis of any abnormal test result. The urinalysis screening program appeared to have significant bearing on diagnosis or treatment in only 13 patients. Abnormalities found in 150 of the 182 patients were either not noted or no further positive action was taken. Thus we concluded that under the conditions of this study the urine screening program added to hospital costs without significant benefit to the patient.


Criteria for establishing a standardized method for determining alkaline phosphatase activity in human serum. We investigated factors influencing alkaline phosphatase activity in the course of developing criteria for the establishment of a standardized method for its determination in human serum at 30 degrees C. The effects of pH, phosphorylatable acceptor (2-amino-2-methyl-1-propanol and diethanolamine), 4-nitrophenyl phosphate, magnesium ion, zinc ion, temperature, volume fraction of specimen, and details of initiation of the reaction have been studied, with use of partly purified enzymes from bone, intestine, liver, and placenta, and sera from patients with a predominant characterized isoenzyme. The purity of the diethanolamine was examined and contaminant monoethanolamine was characterized as a competitive inhibitor. Two sets of recommended conditions are: 2-amino-2-methyl-1-propanol, 0.9 mol/liter; 4-nitrophenyl phosphate, 16 mmol/liter; magnesium ion, 1 mmol/liter; volume fraction of specimen 1/30, and pH30 degrees C 10.5; diethanolamine, 1.8 mol/liter; 4-nitrophenyl phosphate, 18 mmol/liter; magnesium ion, 1 mmol/liter; volume fraction of specimen 1/60, and pH30 degrees C 10.1. Serum is preincubated with all reagents but 4-nitrophenyl phosphate, which is used as the reaction-initiating substrate.


Improved hydrolysis of urinary 17-hydroxycorticosteroid glucuronides with beta-glucuronidase from Helix pomatia, on adding sodium sulfate. Sodium sulfate increases the hydrolysis of urinary 17-hydroxycorticosteroid glucuronides with beta-glucuronidase preparations derived from Helix pomatia because it removes the inhibitory activity of urinary high-molecular-weight substances. For maximum hydrolysis of urinary 17-hydroxycorticosteroid glucuronides, the hydrolysis [5 ml of urine, 0.5 ml of 2 mol/liter acetate buffer (pH 5.0)] should be conducted in the presence of sodium sulfate (final concentration: 80 g/liter) with (a) 600 Fishman units of the enzyme per milliliter of urine (18 h at 52 degrees C) or (b) with 1500 units of the enzyme per milliliter of urine (3 h at 57 degrees C). Under conditions a, analytical recovery of steroid glucuronides added to 12 urine samples was 99 +/- 2.1% (96-102%). Values obtained for 20 urine samples with this method were 99 +/- 2.7% (93-104%) as great as those yielded by a method in which 600 units of the enzyme from bovine liver are used together with sodium sulfate (18 h at 48 degrees C).


Use of an enzymatic kit method for cholesterol, designed for continuous-flow instrumentation, with discrete bichromatic and centrifugal analyzers. I examined a cholesterol-assay kit ("Autoflo", Biodynamics/bmc) designed for use with continuous-flow instrumentation for its use with some discrete analyzers. At pH 7.2, color develops within 3 min upon exposure to cholesterol, then begins to fade. At pH 8, the color develops more slowly but remains stable for at least 15 min after reaching a maximum. A pH 8.8, the color develops still more slowly and standards and patients' sera behave differently. Reagent at pH 7.2 is preferred because assays can be completed most rapidly, but pH 8 reagent must be used with instruments requiring longer periods of incubation. Cholesterol assays can be performed accurately, rapidly, reproducibly, and at low cost with an Abbott ABA-50 and pH 7.2 reagent or with a Gemeni Centrifugal Analyzer and the pH 8 reagent.


Oxidation of alpha-hydroxybutyrate by human serum. 2-Hydroxybutyrate is enzymically oxidized by the LDH of human serum. Optimal concentrations of hydrogen ion, substrate and coenzyme for this oxidation by sera from patients with disease of the heart or liver have been determined at 37 degrees C. The linearity of this reaction is limited to a point at which an assay procedure employing a 2-hydroxyburyrate substrate seems unsuitable.


Salivary excretion and pharmacokinetics of sulfapyridine after sulfasalazine. The concentrations of sulfapyridine (SP) and N4-acetylsulfapyridine (AcSP) in the plasma and saliva of 5 healthy male adults (3 slow and 2 rapid acetylators) were determined as a function of time after a single 2.0-gm oral dose of sulfasalazine (salicylazosulfapyridine). SP absorption commenced 3.5 to 6 hr after sulfasalazine administration and occurred slowly (apparent absorption t1/2s ranged from 1.6 to 5 hr) irrespective of acetylator phenotype. Appreciable differences existed between slow and rapid acetylators with respect to the biologic t1/2 and total body clearance of SP. SP concentrations in the saliva correlated well with those in the plasma. The saliva:plasma concentration ratio for SP was 0.559 +/- 0.027 (mean of 5 subjects +/- SE) and was dependent of plasma concentration and saliva pH. The mean saliva:plasma concentration ratio for AcSP was lower (0.246 +/- 0.056), consistent with the pH-partition hypothesis, and showed considerably more intrasubject and intersubject variation than the ratio for SP. These findings suggest that measurement of SP concentrations in the saliva may be a convenient, noninvasive method for monitoring indirectly the steady-state plasma (serum) concentrations of SP in patients with ulcerative colitis or Crohn's disease who are receiving sulfasalazine.


Enzymes of Penicillium roqueforti involved in the biosynthesis of cheese flavor. The ripening of blue and Roquefort cheeses is accomplished by the concerted and controlled actions of enzymes of the mold Penicillium roqueforti. The properties and effects of the enzymes involved in flavor development (i.e., proteases, lipase and beta-ketoacid decarboxylase) are reviewed. The metabolic activities of both spores and mycelia of P. roqueforti in relation to fatty acid metabolism and flavor generation are discussed. The chemical composition of blue cheese flavor and the simulation of this flavor by fermentation and formulation are briefly surveyed. Some nutritional aspects of blue cheese are cited.


Carfecillin: antibacterial activity in vitro and in vivo. Carfecillin, the alpha-phenyl ester of carbenicillin, hydrolyses rapidly in the presence of serum or body tissues to liberate carbenicillin but hydrolysis is less rapid in aqueous solution. The activity of carfecillin in antibacterial tests in vitro depends upon the extent of hydrolysis to carbenicillin, and in conventional serial dilution tests carfecillin shows an antibacterial spectrum generally similar to that of carbenicillin due to extensive hydrolysis. However, in tests in which the extent of hydrolysis is reduced, carfecillin displays lesser activity than carbenicillin against gram-negative bacilli and greater activity against gram-positive cocci. In the presence of serum carfecillin is hydrolysed rapidly to carbenicillin and the activity shown is solely that of carbenicillin. Unlike carbenicillin, carfecillin is well absorbed in mice after oral administration, producing significant carbenicillin blood concentrations and the compound is as effective by the oral route in the treatment of various experimental mouse infections as is parenteral carbenicillin.


Urinary excretion pattern of methaqualone metabolites in man. A method based on selected ion monitoring for determination of five monohydroxy metabolites of methaqualone in urine has been worked out. By means of this method the time course of metabolite excretion was studied in three healthy volunteers receiving an oral therapeutic dose of methaqualone. In all subjects the main monohydroxy metabolite was conjugated 4'-hydroxymethaqualone, but the relative importance of the five metabolites showed intersubject variation. Metabolite excretion was still going on, when urine sampling was discontinued after 70 hr. Only small amounts (less than 1% of the dose during 70 hr) of unmetabolized methaqualone were excreted. On the other hand, it was confirmed that methaqualone-N1-oxide is an important metabolite. The presence of a hydroxy methoxy metabolite of methaqualone, very probably 4'-hydroxy-5'-methoxymethaqualone, as a minor metabolite was established by comparison with authentic, synthetic material. 8-Hydroxymethaqualone and 2-nitrobenz-o-toluidide, reported by other groups, could not be detected.


Metabolism of sulfadimidine, sulfanilamide, p-aminobenzoic acid, and isoniazid in suspensions of parenchymal and nonparenchymal rat liver cells. Suspensions of isolated liver cells were prepared from rat livers perfused with Ca++-free buffer and 0.05% collagenase. Primary cell suspensions (containing both parenchymal and nonparenchymal liver cells) metabolized sulfadimidine, sulfanilamide, p-aminobenzoic acid, and isoniazid approximately at first order kinetics for at least 4 hr. Suspensions of parenchymal cells had the same metabolic capacity, although the metabolism of isoniazid proceeded at a somewhat reduced rate compared to the primary cell suspensions. Suspensions of nonparenchymal cells did not metabolize sulfadimidine, sulfanilamide, or p-aminobenzoic acid during 4 hr, although such suspensions acted upon isoniazid to some degree. It was concluded that parenchymal rat liver cells may metabolize (acetylate) all four drugs tested, whereas nonparenchymal cells metabolize only isoniazid to any considerable extent.


The metabolism of drugs in isolated rat hepatocytes. A comparison with in vivo drug metabolism and drug metabolism in subcellular liver fractions. The metabolism of drugs in isolated rat hepatocytes has been investigated. Drugs which are metabolized by aromatic hydrolation, aliphatic hydroylation, N-demethylation, or glucuronidation have been used as substrates. With some substrates the rate of metabolism in isolated hepatocytes compares with that in hepatic 900g supernatant fraction or microsomes, but other substrates are metabolized at a slower rate in isolated hepatocytes. For example, the rate of butamoxane hydroxylation in isolated hepatocytes is slower than that in microsomes. However, the rate of hydroxylation is hepatocytes is identical to that in perfused liver. The metabolism of drugs in isolated hepatocytes correlates with in vivo drug metabolism better than does metabolism in the hepatic 9000g supernatant fraction or microsomes.


Comparative metabolism of four allylic barbiturates and hexobarbital by the rat and guinea pig. A method for the extraction and identification of urinary metabolites of allylic barbiturates by gas chromatography and mass spectrometry is described. The metabolites from rat and guinea pig urine were extracted and separated into two fractions (an acidic and a nonacidic fraction) by chromatography on DEAE-Sephadex before converted into suitable derivatives for gas phase analysis. N,N'-dimethyl derivatives were used except in cases where metabolic N-demethylation was possible, in which case N-ethylation yielded more information. Hydroxyl, keto, and epoxy groups were converted into trimethylsilyl (TMS), alkyloxime, and chloro-TMS derivatives, respectively. This procedure was used to identify metabolites present in urine at concentrations as low as 0.1 microgram/ml. The allyl sidechains of secobarbital, alphenal, allobarbital, and aprobarbital were metabolized to epoxides, diols, and, in the case of secobarbital, to a ketol. Other sidechains were usually hydroxylated. Secobarbital was metabolized to compounds containing hydroxyl groups in both chains. Hexobarbital was metabolized by allylic hydroxylation, and no evidence of the epoxide-diol pathway was observed. The significance of the detection of epoxides of the four allylic barbiturates is discussed.


Disposition of triazolam, 8-chloro-6-(o-chlorophenyl)-1-methyl-4H-s-triazolo[4,3-a]benzodiazepine, in the dog. Disposition of triazolam (T), a new, potent, hypnotic agent, was studied in the dog. A single 0.5-mg/kg oral or iv dose of 14C-labeled T was rapidly absorbed, and although 88% was bound to serum proteins, T levels decreased with a half-life of 0.85 hr. Metabolism of T was rapid, with a first-pass effect observed after oral administration. Excretion of drug-related materials was rapid; urinary and fecal excretion of 14C were equal. Urine contained no measurable T, and metabolites were mostly conjugated. The major urinary metabolite was the alpha-HT analog of T, resulting from oxidation of the 1-methyl group of the triazole moiety. Other metabolites identified were the 4-hydroxy and alpha,4-hHT analogs of T, as well as the 1-demethyl analog, which probably results from further oxidation of alpha-hydroxy-T. Evidence also was obtained for two other monohydroxy analogs plus a dihydroxy, monohydroxymonomethoxy, and a dihydroxymonomethoxy analog of triazolam.


[Maridi haemorrhgic fever: a new viral disease (author's transl)]. A new viral disease (Maridi haemorrhagic fever) occurred in the South Sudan in 1976. It was obviously identical with an epidemic which occurred at the same time in Zaire. The virus is morpologically closely similar to the Marburg virus. During the Maridi epemic 124 of 238 patients died (52%). Characteristic symptoms were fever and headache (100%), diarrhoea (83%), retrosternal pain (82%), vomiting (68%), haemorrhages (62%), morbilliform or vesicular rash (52%). At post-mortem there were changes in liver, kidney, myocardium and lungs, similar to those in the Marburg virus disease, as were those observed in bone marrow and peripheral blood. Despite these analagous findings, the clinical course and results of immunofluorescence indicate that it is a new disease. The epidemic ended after suitable isolation measures had been taken. There was no specific treatment but in some cases convalescent plasma and interferon were tried. The disease is transmitted among humans by direct contact or by contact with blood or excreta of patients. No animal reservoir has been found. It is possible for this disease to be imported also into countries with a modorate climate.


Studies on isometheptene metabolism. Identification and stereochemistry of a major metabolite isolated from rat urine. By gas chromatography-mass spectrometry of both underivatized samples and N-acetates, the major urinary metabolite of the antispasmodic drug (+/-)-isometheptene in the rat was identified as trans-2-methyl-6-methylamino-2-hepten-1-ol. The structure and stereochemistry of the metabolites was confirmed by comparing the properties of its N-acetate with those of an authentic sample of the N-acetate of trans-2-methyl-6-methylamino-2-hepten-1-ol which was obtained by a stereospecific trans-allylic hydroxylation of isometheptene acetate with selenium dioxide in ethanol. cis-2-Methyl-6-methylamino-2-hepten-1-ol was identified as a minor urinary metabolite of isometheptene in the rat.


[Treatment of peptic ulcer in the Zollinger-Ellison syndrome with histamine H2-receptor antagonists (author's transl)]. Histamine H2-receptor antagonists metiamide and cimetidine were used in the treatment of severe peptic ulceration in Zollinger-Ellison syndrome. The ulcerations were completely healed in all four patients after treatment lasting from six weeks to four-and-a-half-months. Two patients developed recurrent ulcer after the treatment had stopped, but responded to a second course. One patient developed hepatitis B during cimetidine treatment and it is possible that the course of the hepatitis was unfavourable affected by cimetidine. But no other side effects were noted nor was there a significant change in basal serum-gastrin concentration or an increase in H+ secretion. Total gastrectomy remains the treatment of choice in Zollinger-Ellison syndrome, but cimetidine should be considered if the patient refuses operation or operation is not feasible because of a poor general state.


[Minoxidil in the treatment of malignant hypertension (author's transl)]. In 21 of 23 patients with hypertension unresponsive to other treatment minoxidil, a new antihypertensive drug acting via peripheral vasodilatation, lowered their blood pressure from 191 +/- 19/117 +/- 12 MM Hg to 147 +/- 13/117 +/- 12 mm Hg. The drug causes a reflex tachycardia and must therefore be combined with beta-blockers. Furthermore, an effective diuretic must also be used because minoxidil causes sodium retention. Hypertrichosis is an important side-effect for which the drug may have to be discontinued, especially in young women. Orthostasis did not occur in the reported series. The authors recommend that the drug be made available for the treatment of malignant hypertension.