bluuebunny/crossref_metadata_2025 huggingface dataset:
ISOLATION AND COMPOSITION OF AVIAN EGG YOLK GRANULES AND THEIR CONSTITUENT α- AND β-LIPOVITELLINS
Authors: Burley R. W. , Cook W. H.
Published: December 2009

The yolk granules from hen's egg represent on a dry basis 23% of the yolk solids, and they contain about 90% of the protein phosphorus, 95% of the iron, and nearly 70% of the calcium in yolk. Ultracentrifugal and other analyses on solutions of the granules show that they are 70% α- and β-lipovitellin in an approximate ratio of 1:1.8, 16% phosvitin, and 12% low-density lipoprotein. The properties and composition of the two lipovitellins isolated from the granules are the same as those isolated from solutions of whole yolk. Further purification reduces the protein phosphorus in α-lipovitellin to 0.50% and in β-lipovitellin to 0.27%, and this confirms that α-vitellin has a higher phosphorus content. Experiments at low temperature suggest that phosvitin exists in the granules as a high molecular weight complex.
SOME PROPERTIES OF THE SOLUBLE ESTERASES OF HUMAN LIVER
Authors: Ecobichon D. J. , Kalow W.
Published: December 2009

Zone electrophoresis on starch gel in conjunction with various histochemical staining methods was applied to the study of the water-soluble esterases of liver. The results indicated that in regard to electrophoretic migration and enzymatic properties, none of the human liver esterases was identical with any of the human serum esterases.
THE RELATION BETWEEN PHOSPHATE METABOLISM AND THE TRANSPORT OF CATIONS ACROSS THE CELL MEMBRANE IN THE HUMAN ERYTHROCYTE
Authors: Blostein Rhoda , Rubinstein David , Denstedt Orville F.
Published: December 2009

The rate of passage of cations across the red cell membrane, in the direction of the respective ionic gradients, in blood preserved with glucose at 4 °C, is not diminished upon the addition of inosine, notwithstanding the induced formation of substantial amounts of phosphate esters, including ATP, in the cells. The movement of cations, however, is retarded on the addition of glucose or inorganic phosphate, and on increase in the concentration of hydrogen ions. It would appear, therefore, that the movement of cations across the membrane, at 4 °C, is influenced little, if at all, by the metabolic activity of the cell.When the temperature of the preserved blood is returned to 37° the rate of movement of cations across the cell membrane against their respective gradients is greatest in cells which had either been preserved or have been incubated with inosine even if the remainder of the inosine has been removed. Inosine is more effective than glucose in bringing about the restoration of cation composition in preserved red cells at 37°. The degree of restoration is greater in the presence of glucose than in its absence. Arsenate inhibits the transport of cations against the gradients. Evidence is given that the capacity of the cells to restore the cation distribution at 37 °C is determined largely by the concentration of the phosphate ester intermediates.
TRIGEMINAL PROJECTIONS IN THE RETICULAR FORMATION OF THE PONS IN THE CAT
Authors: Langlois J. M. , Lamarche Guy
Published: December 2009

The projections of the trigeminal nerve in the pontine reticular formation of the cat have been investigated by recording unit activity, after physiological stimulation of the face, in 30 "encéphales isolés" preparations. No somatotopical arrangement was found but a high degree of spatial convergence onto pontine reticular units exists and a certain degree of functional organization was observed.
PROPERTIES OF HUMAN PLASMIN
Authors: Ronwin Edward
Published: December 2009

Several aspects of the properties and preparation of human plasmin are considered. It appears that glycerol activation of the proenzyme is a peculiar property dependent in part on the structure of the glycerol molecule since closely related compounds are without effect. Observations on the influence of ionic strength, on ion activation and inhibition of the enzyme, on substrate specificities, and on preparative procedures are recorded and comparisons with similar data on related bovine enzymes are made.
THE LIPID COMPOSITION OF BACILLUS CEREUS AS INFLUENCED BY THE PRESENCE OF ALCOHOLS IN THE CULTURE MEDIUM
Authors: Kates M. , Kushner D. J. , James A. T.
Published: December 2009

Cells of Bacillus cereus grown in an alcohol-free medium (control cells) had a lipid content of 2.6 ± 0.4%, on a dry weight basis. About half of the lipids consisted of phosphatides, including phosphatidyl ethanolamine (40%), phosphatidyl glycerol (28%), lecithin (6%), lyso compounds (10%), and three acidic phosphatides of unknown structure. The fatty acids of the total lipids were predominantly saturated, the major components being branched-chain C13, C15, and C17acids. The neutral lipids consisted mostly of diglycerides, with a small amount of triglycerides. Five to ten per cent of the lipids was obtained as unsaponifiable material, consisting chiefly of long-chain (n-C16and n-C18) alcohols, and having traces of long-chain aldehydes (derived from plasmalogens).Cells grown in the presence of alcohols usually had a higher phosphatide content, a correspondingly lower non-phosphatide content, and a higher non-saponifiable content than control cells. Total lipid content or relative proportions of the phosphatide components in alcohol-grown cells did not differ significantly from those of control cells.
PHOSPHORYLATION OF DIGLYCERIDES BY RAT BRAIN
Authors: Strickland K. P.
Published: December 2009

The addition of D-α,β-dimyristin was observed to stimulate by three to six times the labelling of phospholipids from radioactive inorganic phosphate (Pi32) by glycolysing homogenates and respiring mitochondria of rat brain. The increase in labelling was confined to the glycerophosphate (GP) isolated by two-dimensional chromatography from the water-soluble hydrolysis products obtained on weak alkaline treatment of the labelled phospholipids. The GP formed under these conditions is presumed to be derived mainly from phosphatidic acid formed by the phosphorylation of the diglyceride. A similar effect was observed for D-α,β-dipalmitin, D-α,β-diolein, and natural diglycerides prepared from either egg lecithin or spinal cord lecithin, but not for D-α-β-distearin. L-α,β-Diolein was much less effective than the D-isomer, suggesting a stereospecificity on the part of the enzymic phosphorylation of diglyceride. Experiments on the effects of the omission of Mg++and the addition of glycolytic inhibitors on the stimulation of the labelling from Pi32caused by D-α,β-dimyristin and D-α,β-diolein in the anaerobic homogenate system suggested that the increased phosphorylation caused by added diglycerides was closely coupled to active glycolysis. A comparison of the relative specific activity of the lipid P, following incubation of Pi32and ATP32in the anaerobic homogenate system inhibited by fluoride with and without D-α,β-diolein added, showed that the phosphate of the newly formed phosphatidic acid was derived from ATP, suggesting the presence of a D-α,β-diglyceride kinase.
PHARMACOLOGY OF PEMOLINE
Authors: McColl J. D. , Rice W. B.
Published: December 2009

Pemoline (5-phenyl-2-imino-4-oxo oxazolidine) produced an increase in spontaneous motor activity of a co-ordinated type in mice. It was observed to prevent and to reverse reserpine-induced motor depression in a manner analogous to that of d-amphetamine. The order of activity as a motor stimulant fell between that of d-amphetamine and caffeine but had a slower onset of action. At low doses, pemoline potentiated the loss of righting reflex induced by hexobarbital and ethanol but it antagonized these agents at high doses. Pemoline antagonized nicotine-induced clonic convulsions in mice. Like amphetamine it produced an increase in urine output and sodium and potassium excretion in the male guinea pig.
STUDIES ON THE UPTAKE OF REAGIN BY POLYAMINOSTYRENE–RAGWEED COMPLEXES
Authors: Delorme P. , Richter M. , Grant S. , Rose B.
Published: December 2009

The various factors governing the uptake of reagin by insoluble antigenic complexes prepared by incubating ragweed pollen extract (WSR) with either polyaminostyrene (PAS) or diazopolyaminostyrene (DPAS) have been investigated. It was found that PAS–WSR was as capable of binding reagin as DPAS–WSR. This reaction was shown to be specific and the quantity of reagin bound to the complex was found to vary with the amount of reagin present during the incubation and the duration of incubation. The binding was independent of the concentration of reagin in the incubation mixture and of the temperature of incubation.
SENSITIVITY OF THE RAT TO INCREASING DOSES OF DEXTRAN
Authors: Jasmin Gaetan , Bois Pierre , Su Mai-Shian
Published: December 2009

Increasing doses of dextran, a commercial 6% solution, were injected intravenously into both intact and adrenalectomized rats to evaluate the dose–response relationship. The minimum dose capable of producing an edema with 100% incidence was approximately 30 mg/kg in intact and only 4 mg/kg in adrenalectomized rats. Lower doses produced responses of decreasing intensity and incidence with a longer period of onset. Conversely, higher doses resulted in a shorter period of onset and a more intense reaction until a toxic dose was reached, beyond which cyanosis and shock appeared. Adrenalectomized rats reacted similarly to intact ones except that their response occurred at a lower dose range; they could not withstand the toxic effect of higher doses and died of circulatory failure. The fact reported by other workers that the edema is more intense and appears more rapidly after intravenous injection of minute rather than large quantities of dextran was not confirmed; the existence of a "critical dose" that does not produce any edema was not substantiated.
PREPARATION AND PROPERTIES OF POLYSACCHARIDE–LIPID COMPLEXES FROM SERRATIA MARCESCENS
Authors: Srivastava H. C. , Breuninger Evelyn , Creech Hugh J. , Adams G. A.
Published: December 2009

Several polysaccharide fractions possessing pronounced antitumor activity were isolated from the polysaccharide–lipid–protein complex elaborated by Serratia marcescens. These fractions were obtained after phenol extraction of the cellular material, by ultracentrifugation and precipitation with ethanol and Cetavlon. They contained glucose, mannose, rhamnose, glucosamine, glucuronic acid, and mannuronic acid in different proportions. Each representative fraction caused regression of well-established solid tumors in mice but the dosage requirements varied considerably. One fraction containing glucose, mannose, and glucosamine, but no uronic acids, and having a high solubility in dilute sodium chloride solution and in aqueous acetone, was an exceptionally potent antitumor agent. Another fraction containing galactose and arabinose in addition to several of the usual components was found to be least active. From this work and that of other investigators, it is apparent that Serratia marcescens produces a spectrum of polysaccharides and lipopolysaccharides, the chemical composition and biological properties of which depend on the strain of organism, the culture conditions, and the methods employed for isolation of the active agents.
ENZYMATIC AND METABOLIC ADAPTATIONS: I. CHANGES IN INTACT RATS SUBJECTED TO DIETARY MODIFICATIONS
Authors: Willmer J. S. , Foster T. S.
Published: December 2009

A study of hepatic enzymes concerned in glucose metabolism was made after transfer of rats from a standard laboratory ration to three experimental diets. The change to two high-carbohydrate diets resulted in elevated levels of enzymes of the hexosemonophosphate shunt. Glucose-6-phosphatase, phosphoglucomu-tase, and phosphoglucoseisomerase exhibited an initial transitory decrease in activity, succeeded by restoration to normal or above-normal levels. Animals fed a low-glucose diet showed a tendency towards decreased activity of all enzymes except glucose-6-phosphatase. Hepatic oxidation of glucose-1-C14and glucose-6-C14and liver glycogen levels were also measured. These results are discussed in relation to the observed enzyme changes.
INHIBITION OF CATALASE BY CARBOXYLIC ACIDS RELATED TO DISSOCIATION AND ASSOCIATION OF THE APOPROTEIN
Authors: Itoh Michio , Nakamura Yasuharu , Shibata Kazuo
Published: December 2009

The inhibitory effects of aliphatic and aromatic carboxylic acids (formic, acetic, propionic, butyric, benzoic, and salicylic acids) on catalase at pH 7.0 were studied by measuring the catalatic activity as a function of reagent concentration, and the results were correlated with the data obtained simultaneously by spectroscopic and ultracentrifugal analyses. The inhibition by salicylic and benzoic acids proceeds in two steps. In the first step, the activity drops to a certain level, and the sedimentation peak of the native catalase is unaltered. The second step of inhibition is accompanied by the dissociation of the catalase molecule into subunits, and the absorption spectrum is changed greatly. The inhibition by the aliphatic carboxylic acids except formic acid proceeds also in two steps in which the second step of inhibition is accompanied by the association of the catalase molecules. The inhibition by formic acid obeys the mechanism of the combination between heme and the free acid rather than its anion. These different types of inhibitions at neutral pH are discussed in relation to the data obtained previously at acidic pH's.
A METABOLISM CAGE DESIGNED FOR USE WITH MINK
Authors: Sinclair D. G. , Evans E. V.
Published: December 2009

A metabolism cage suited to the size and habits of the mink was designed and constructed. This cage has proved satisfactory for studies of feed consumption and for the separate collection of faeces and urine uncontaminated with particles of spilled feed.
EFFECT OF SEVERE COLD (−5 °C) ON THE ENDOCRINE FUNCTION OF THE TESTIS IN THE ALBINO RAT
Authors: Perrault M. J. , Dugal L. P.
Published: December 2009

Cryptorchism, caused surgically, and cold exposure have been studied separately and in combination: the morphological characteristics, organ weights, and histological appearance of the testes and of the main sexual accessories have been evaluated. Physiological information derived from morphological data reveals that the effect of cold is twofold: (a) somatic or non-endocrine and (b) purely endocrine; the two effects are superimposed and additive, but distinct. Thus, the gonadal response of the male rat to cold, within the time limit of the present investigation, assumes the appearance of a "physiological castration".
THE SIGNIFICANCE OF HUMAN BLOOD TRYPSIN; DIRECT DETERMINATION OF THROMBIN AND PLASMIN IN HUMAN PLASMA
Authors: Ronwin Edward
Published: December 2009

The previously described method for human plasmin determination has been simplified and applied directly to plasma. A virtually identical method for the direct determination of human thrombin in plasma is also presented. Both procedures are quantitative and clinically feasible. The existence in plasma of a non-clotting, only slightly fibrinolytic, active tryptic enzyme, Human Blood Trypsin, is firmly established by the data. The suggestion is made that human blood trypsin may be the activator in the proenzyme to enzyme conversion system for both plasmin and thrombin. Further, both enzymes may arise from different derivatives of a common precursor protein.
MEASUREMENT OF HUMAN BONE FORMATION BY MEANS OF TETRACYCLINE LABELLING
Authors: Frost Harold M.
Published: December 2009

Chalkley's method combined with fluorescence microscopy was used to measure the amount of bone formed in a known time in a known amount of bone in 57 patients in whom the frontier line of bone formation was labelled by the administration of tetracycline. Calculated mean values for the years required to form an amount of new bone equal to the original amount are 2.2 years for a 5-year age group, 28.4 years for a 26-year age group, 37 years for a 47.8-year age group, and 37.6 years for a 67.4-year age group.These values are termed the formation times.
SEPARATION OF BILE ACID CONJUGATES BY ION EXCHANGE CHROMATOGRAPHY
Authors: Gordon B. A. , Kuksis A. , Beveridge J. M. R.
Published: December 2009

A simple and reliable method for the separation of bile acid conjugates in quantities ranging from a few milligrams to several grams has been developed utilizing ion exchange resins. The bile acid conjugates were absorbed from an aqueous 25% ethanol solution on a Dowex-1 anion exchange column (acetate form). After the column was washed with aqueous 25% ethanol, the glycine conjugates were eluted with 0.05 N HCl in 25% ethanol and the taurine conjugates with 0.5 N HCl in 25% ethanol. The method permitted a complete resolution of the glycine and taurine conjugates. In addition, there was an effective though not complete separation of the tri- and di-hydroxy cholanic acid derivatives within each conjugate group. Using this method satisfactory fractionations have been performed on gallbladder bile from dog, ox, and man.
THE EFFECT OF FLOW RATE AND OSMOLARITY OF LUMEN CONTENTS ON CALCIUM AND WATER ABSORPTION FROM THIRY-VELLA FISTULAS IN DOGS
Authors: Cramer Carl F. , Haqq Tennyson A.
Published: December 2009

The effect of a number of factors which locally might affect intestinal absorption of calcium in vivo was studied. Changes of osmolarity or of sodium concentration altered neither the calcium absorption rate nor the maximal absorptive capacity found at higher calcium concentrations. Under static conditions in a healed jejunal loop, calcium was absorbed more rapidly at first, but after 40 minutes the rate of absorption was essentially constant. Water absorption was approximately constant throughout the 2 hours. On the other hand, when the solutions flowed slowly through the gut loop, calcium was absorbed six times, and water four times more rapidly. The importance of these findings to normal absorption is discussed.
IMMUNOLOGICAL STUDIES OF LYMPHOID LEUKEMIA IN THE AKR MOUSE
Authors: Guthrie R. K. , Ingebrigtsen N. A. , Savage N. , Hinkle D. C. , Farris W. J.
Published: December 2009

Experiments are reported showing some slight protective capacity of guinea pig antimouse leukemic tissue serum to protect the AKR mouse against the BW5147 tumor, when the serum is first adsorbed to remove precipitating antibody for the tissue cell antigens. The degree of protection is slight, and all mice eventually died of the tumor development. Results of one injection of tumor tissue – oleic acid emulsion show up to 46% survival of the immunized mice following challenge injections of active tumor preparation. No protection is seen after a similar injection of tumor material which had remained frozen for several months. Repeated injection of frozen tumor tissue produced leukemic tumor development in test mice, indicating that this material retains some activity under these conditions, and that sufficient immunity cannot be produced by these injections to protect against the disease.
PAPER AND THIN-LAYER CHROMATOGRAPHY OF THE HYDROXYSKATOLES
Authors: Heacock R. A. , Mahon M. E.
Published: December 2009

The hydroxyskatoles could not be effectively separated chromatographically with a number of solvent systems on Whatman No. 1 paper or acetylated paper. The use of formamide-treated paper and certain non-polar solvent systems enabled the 4- and 7-hydroxyskatoles to be separated from each other, and in turn from mixtures of the 5- and 6-hydroxyskatoles. This latter pair of isomers could not be separated by this method. Complete separation of all four isomers was readily achieved using thin-layer techniques.
PURIFICATION AND SOME PROPERTIES OF AUTOPROTHROMBIN C
Authors: Seegers Walter H. , Cole Edmond R. , Harmison Charles R. , Marciniak Ewa
Published: December 2009

Methods were developed for the isolation of autoprothrombin C, which is the second enzyme obtained from purified bovine prothrombin. In the presence of lipids and standardized conditions 0.35 μg of the purified autoprothrombin C were sufficient for clotting recalcified plasma in 15 seconds. Some physicochemical properties are as follows: S20, wis 2.27S, the diffusion constant 8.4 × 10−7 cm2/second, and the partial specific volume 0.695. The molecular weight from physicochemical measurements was 21,500. All amino acids were found, but only 1 molecule of methionine. On the basis of amino acid composition the molecular weight was found to be 27,000, giving an average of 24,200 for our two determinations. Prothrombin contains sufficient of each amino acid residue to supply autoprothrombin C and thrombin. Autoprothrombin II, however, has only sufficient amino acids for either autoprothrombin C or thrombin, but not both. The purified autoprothrombin C contained 7% carbohydrate (orcinol) and 3.8% hexosamine. It was stable at pH 7.2 for more than a week at room temperature, and longer in subzero glycerol solution. Autoprothrombin C was used to obtain a single precipitin band in agar diffusion plates with antibody to prothrombin. The band also identified with a single plasma antibody.
ENZYMATIC PRODUCTION OF (+) threo-9,10-DIHYDROXYOCTADECANOIC ACID IN THE SPORES OF PLANT RUSTS
Authors: Tulloch A. P.
Published: December 2009

Evidence is presented to show that an epoxide-hydrolyzing enzyme system is present in the uredospores of Puccinia graminis Pers. f. sp. tritici Erikss. and Henn. race 15B and in the teliospores of Gymnosporangium clavariiforme (Pers.) DC. Incubation of the spores results in a partial conversion of cis-9,10-epoxy-octadecanoic acid, which is present in the spore oil as a glyceride, to (+) threo-9,10-dihydroxyoctadecanoic acid.
LOSS OF SOLUBLE MATERIALS FROM IRRADIATED THYMOCYTES IN VITRO
Authors: Myers D. K. , DeWolfe Donna E. , Araki Kimiko , Arkinstall W. W.
Published: December 2009

Following exposure to X-radiation in doses above 100 r, rat thymocytes lose soluble compounds into the extracellular fluid during incubation in Krebs–Ringer solution at 37 °C and pH 7.4. Acid-soluble ribonucleotide and potassium ion concentrations in the irradiated cells decreased markedly after an initial lag period of 1 hour, during which the irradiated thymocytes could not be distinguished from control cells. These losses were accompanied by a gradual depolymerization of deoxyribonucleic acid. At least one labile enzyme, deoxycytidylate deaminase, also became inactivated. A similar loss of nucleotides and potassium ion from the thymus gland also occurred following its irradiation in the intact animal.A decrease in pH or temperature during incubation of irradiated thymocyte suspensions minimized the loss of potassium from the cells; the same treatments were found previously to decrease the sensitivity of these cells to the lethal effects of X-radiation. The loss of soluble materials appeared to be related to subsequent death of the cells. However, rapid loss of intracellular potassium from thymocytes is probably due to a breakdown of intracellular binding structures rather than to inhibition of active ion transport.
QUANTITATIVE GAS–LIQUID CHROMATOGRAPHY OF SELECTED BILE ACID ESTERS ON SE-30, QF-1, AND XE-60 SILICONE POLYMERS
Authors: Kuksis A. , Gordon B. A.
Published: December 2009

The suitability of the silicone polymers, SE-30, QF-1, and XE-60, for the quantitative separation of the common bile acid methyl esters, their acetates, and trifluoroacetates was investigated using narrow bore columns (1/8 in. × 3 ft or 5 ft, 195°–220 °C, 1–2% (w/w) stationary phase). Under the experimental conditions selected, complete and essentially quantitative separations were obtained only with the trifluoroacetylated bile acid methyl esters on QF-1 columns. The separations of the acetylated methyl esters were complete on the SE-30 columns, but for quantitative determinations the area response obtained in the hydrogen flame ionization detector had to be corrected for losses during chromatography. The other columns and derivatives either failed to give complete separations or the area response could not be corrected in any simple way to give the weight or mole proportions of the test mixture.
ACTION OF ORGANOPHOSPHORUS COMPOUNDS UPON ESTERASES OF HUMAN LIVER
Authors: Ecobichon D. J. , Kalow W.
Published: December 2009

Human serum and liver esterases separated electrophoretically in starch gel were exposed to two series of organophosphorus insecticides. One series consisted of compounds active per se, the other of analogues requiring metabolic or chemical conversion to produce potent anticholinesterases. The results indicated that only one fraction of the liver, designated as zone L-2, is inhibited by low concentrations of all insecticides. This fraction shows a similar pattern of susceptibility to different inhibitors as does human serum cholinesterase. Of the other two zones of activity in liver, zone L-1 was found to be more susceptible to activated thionate, dithioate, and thioether derivatives than was zone L-3, while the latter zone was more susceptible to phosphates active per se.
ON THE ORIGIN OF THE CELLULASE AND CHITINASE OF HELIX POMATIA
Authors: Strasdine G. A. , Whitaker D. R.
Published: December 2009

Specimens of the snail Helix pomatia were fed for 2 days at room temperature after emergence from hibernation at 4° and total soluble protein, total units of cellulase activity towards carboxymethyl cellulose, and total units of chitinase activity towards glycol chitin were determined in the digestive juice, hepatopancreas, and intestinal wall. Comparisons of these values with those for hibernating snails showed that emergence from hibernation and resumption of feeding was accompanied by a substantial decrease in soluble protein in the hepatopancreas, and a substantial increase in soluble protein cellulase and chitinase in the digestive juice. Cellulase and chitinase in the digestive juice showed little change in specific activity and were present in approximately the same ratio as in the hepatopancreas and intestinal wall. The volume of digestive juice in snails which had been deprived of food after a brief posthibernation feeding increased significantly with starvation times up to at least 5 days but the concentration of protein, cellulase, chitinase, and helicorubin showed no significant change. Plate counts for viable bacteria in the hepatopancreas indicated that the hepatopancreas was virtually sterile. The difficulty of reconciling these findings with the hypothesis of a bacterial origin for the cellulase and chitinase in snail digestive juice is discussed.
IN VITRO EFFECTS OF SUBSTITUTED IODOPHENOLS ON CATECHOL-O-METHYLTRANSFERASE
Authors: D'Iorio A. , Mavrides C.
Published: December 2009

The kinetic study of a new inhibitor of catechol-O-methyltransferase, 3,5-diiodo-4-hydroxybenzoic acid (DIHBA), previously reported by the authors (1), shows it to act in a competitive fashion. Instead of the crude enzyme preparation of the early experiments, a partially purified enzyme has been used throughout the present series of experiments and new substances have been tested with respect to their inhibiting effects. Thus, O-methyl-DIHBA is found to be inactive, while 3,5-diiodosalicylic acid (DISA) inhibits competitively and 3,5-diiodo-4-hydroxypyridine (DIHP) noncompetitively as indicated by the Lineweaver and Burk plots.3,5-Diiodo-4-hydroxyphenylpyruvic acid (DIHPA) produces a progressive and partly reversible inhibition, while 3,5-diiodotyrosine (DIT) has no effect on the activity of the enzyme. m-Fluorotyrosine, o-fluorophenol, and o-iodophenol are similarly inactive.
DDT AND THE METABOLISM OF VITAMIN A AND CAROTENE IN THE RAT
Authors: Phillips W. E. J.
Published: December 2009

The utilization of vitamin A and carotene has been studied in the rat following the feeding of DDT in the diet over a range of concentrations from 0 to 100 p.p.m. for periods up to 72 days. In two of three experiments, the feeding of over 10 p.p.m. DDT decreased the utilization of orally administered carotene. In two experiments, the feeding of 10 p.p.m. DDT or over decreased liver storage of vitamin A when vitamin A per se was administered. The storage of vitamin A was similarly reduced when a diet containing both DDT and carotene or DDT and vitamin A was fed.
END GROUP AND SEDIMENTATION DATA ON FRAGMENTED HIGH MOLECULAR WEIGHT RIBONUCLEATES
Authors: Lane B. G. , Diemer J. , Blashko C. A.
Published: December 2009

A method for end group analysis of ribonucleate preparations using purified snake venom phosphodiesterase is described. Unusual difficulties encountered with the method are discussed. The technique is useful for detection of end groups resulting from enzymic and chemical fragmentation of high molecular weight ribonucleates. Preliminary studies indicate that the method has limited usefulness because of a spontaneous hydrolysis of ribonucleates which occurs under the conditions which are optimal for hydrolysis with snake venom phosphodiesterase (pH 9, in the presence of magnesium). Physicochemical studies have shown that the pronounced dependence of sedimentation coefficient on ionic strength which has been reported by other investigators is also observed with fragmented high molecular weight ribonucleates and with 16S + 24S ribonucleates of Ehrlich ascites cells. The changes of sedimentation rate are associated with configurational and aggregation effects.
POTASSIUM MOVEMENTS IN RAT UTERUS STUDIED IN VITRO: II. EFFECTS OF METABOLIC INHIBITORS, OUABAIN, AND ALTERED POTASSIUM CONCENTRATIONS
Authors: Daniel Edwin E.
Published: December 2009

1. Sodium fluoride (10−2 M), 2,4-dinitrophenol (10−4 M), and iodoacetate (10−4 M) caused a slight decrease in potassium uptake by the uterus and fluoride and dinitrophenol caused a larger and immediate increase in efflux, resulting in a net loss of potassium. There was apparently a delayed increase in efflux caused by iodoacetate. The effects of inhibitors on efflux were not prevented by the absence of external potassium. The effects of fluoride suggested that it produced inhomogeneity in uterine potassium and analysis of the longitudinal muscle layer separately from the remainder of the uterus suggested that efflux was speeded more in myometrium than in endometrium. This was attributed to the prolonged contracture induced by fluoride. The depolarization required to explain the increases in efflux produced by fluoride and DNP was sufficient to explain the decreases in influx. It was postulated that these inhibitors act by causing depolarization which might be the result of inhibition of an electrogenic sodium pump. Iodoacetate 10−3 M caused a 50% reduction in potassium influx and probably a large immediate increase in efflux, but no evidence was obtained that this concentration caused contraction.2. Ouabain in concentrations as high as 10−5 M had only minor effects on potassium inward and outward movements and on reaccumulation of potassium and extrusion of sodium during recovery from exposure to the cold. The resistance of rat uteri to cardiac glycosides derives either from insensitivity in rat tissues or from a unique feature of sodium transport in the rat uterus.3. When KCl was added to the Ringer fluid, there was no net gain of cellular potassium relative to dry weight. Osmotic balance was achieved mainly by water loss from cells, but uncertainty as to the extracellular fluid volume prevented a definite conclusion. When KCl was omitted from the Ringer fluid, there was a 50% decrease in efflux, suggesting that a part of the potassium movement was "exchange diffusion". The assumption of exchange diffusion also would aid in explaining the observed flux ratio near unity in view of the values reported for membrane potentials of uterine cells. Owing to the lack of data regarding intracellular activity of potassium and the incompleteness of data on membrane potentials of uterine cells, it was not possible to prove whether active influx of potassium was present or absent in addition to that entering passively either by free diffusion or exchang diffusion.
PARTIAL PURIFICATION AND PROPERTIES OF PROLYL-RNA SYNTHETASE OF RAT LIVER
Authors: Fraser M. J. , Klass D. B.
Published: December 2009

Prolyl-RNA (prolyl ribonucleic acid) synthetase has been purified 30-fold from a 105,000 × g supernatant of a rat liver homogenate by precipitation at pH 5.0, heat treatment at 55 °C for 3.0 minutes in the presence of 1.0 mM ATP (adenosine triphosphate), and by ammonium sulphate fractionation. The enzyme catalyzed proline-dependent ATP-32PP (PP, inorganic pyrophosphate) exchange and the formation of prolyl hydroxamate and of prolyl-RNA. Although the enzyme did not catalyze the formation of hydroxyprolyl-RNA, it catalyzed a slight hydroxyproline-dependent ATP-32PP exchange and the formation of a small amount of hydroxyprolyl hydroxamate which was much less than the amount of prolyl hydroxamate formed under the same conditions. The enzyme is thus not quite specific for proline activation, but is specific for amino acyl-RNA formation. It is probably concerned in protein biosynthesis.In the proline-dependent ATP-32PP exchange reaction the enzyme showed optimum activity in the pH range 6.2–8.2 and no activity at pH 5.0. The apparent Kmfor proline in this reaction was found to be 0.43 mM. Mg++was required for activity. Prolyl-RNA formation was optimal at pH 8.0. The apparent Kmfor proline in this reaction was found to be 2.5 μM. The effects of some proline analogues on proline activation were studied. Hydroxyproline and thioproline were found to inhibit both proline-dependent ATP-32PP exchange and prolyl-RNA formation. Thioproline was a competitive inhibitor of the exchange reaction and showed a KIof 0.95 mM. Pyrrolidone carboxylate had no appreciable effect on proline activation.
CHARACTERISTICS OF ERYTHROCYTES OF DIFFERENT AGES: II. ENZYME ACTIVITY AND OSMOTIC FRAGILITY
Authors: Sass Martin D. , Levy Lester M. , Walter Harry
Published: December 2009

The activity of glutamic oxaloacetic transaminase, lactic acid dehydrogenase, and catalase in red cells of different ages has been studied with a serial osmotic fragility technique. Two populations of young cells, one fragile and one resistant, have been differentiated and shown to contain increased levels of glutamic oxaloacetic transaminase and average (normal) levels of catalase. Lactic acid dehydrogenase levels were shown to be increased only in the fragile population of young cells. These findings were confirmed with similar studies on abnormal red cell populations containing increased numbers of young red cells and reticulocytes. Although their identity has not been established, the results suggest that the fragile and resistant young red cell populations are composed mainly of reticulocytes and fully matured young cells, respectively.
CONVERSION OF DISACCHARIDES TO THE CORRESPONDING GLYCOSIDE-3-ULOSES BY INTACT CELLS OF AGROBACTERIUM TUMEFACIENS
Authors: Fukui S. , Hochster R. M.
Published: December 2009

The conversion of trehalose, maltose, and lactose to their corresponding glycoside-3-uloses was demonstrated with growing, intact cells of Agrobacterium tumefaciens. Moreover, 3-ketotrehalose, 3-ketomaltose, and 3-ketolactose, the products of these biological conversions, were obtained in the crystalline state and their properties and physical constants are reported here. Structural analyses were carried out as far as possible using such methods as: periodate oxidation, acid and specific enzymatic hydrolysis, and borohydride reduction followed by hydrolysis and subsequent product identification.
PIGEON MUSCLE MITOCHONDRIA: ION CONCENTRATIONS, OXIDATIVE PHOSPHORYLATION, SWELLING, AND EXTRAPARTICULATE SPACE
Authors: Marcus G. J. , Manery J. F.
Published: December 2009

Metabolically active mitochondria were isolated from pigeon breast muscle in cold 0.45 M sucrose with ATP, EDTA, and tris buffer at pH 7.4. Fresh mitochondria were analyzed for sodium, potassium, nitrogen, iron, and water. They were morphologically intact and showed respiratory control, respiration being limited by the phosphate acceptor and stimulated by dinitrophenol. The respiratory rate was the same in the Warburg respirometer as that in the polarograph chamber; no effect of agitation was observed. The rates of oxygen consumption over short periods of time were 30–40 μ atoms per hour per mg N for α-keto-glutarate and glutamate, 16 for malate, and 1.3 for β-OH butyrate; except in the last case, satisfactory P/O ratios were obtained. A soluble, heat-stable muscle factor, not precipitated at 100,000 × G, stimulated respiration with each substrate but did not affect phosphorylation. From optical density measurements of muscle mitochondria they appeared to behave as moderately good osmometers; only slight swelling occurred during oxidative phosphorylation, but this increased somewhat when respiration ceased. The osmotic dead space was estimated at 60% of the mitochondrial volume. With polyvinylpyrrolidone the extraparticulate space was found to be 27.8 ± 1.8%.
ACETYLCHOLINE IN INVERTEBRATE NERVOUS SYSTEMS
Authors: Florey Ernst
Published: December 2009

A survey is presented of the distribution and possible functional significance of acetylcholine in the animals of various invertebrate phyla.
THE SEPARATION, ESTIMATION, AND CHARACTERIZATION OF ALKALI-STABLE OLIGONUCLEOTIDES DERIVED FROM COMMERCIAL RIBONUCLEATE PREPARATIONS
Authors: Singh H. , Lane B. G.
Published: December 2009

Methods are described which are suitable for the quantitative analysis of the alkali-stable oligonucleotides which result from the hydrolysis of ribonucleates in molar alkali at room temperature for 90 hours. The alkali-stability of the oligonucleotides is presumed to result from 2′-O-methyl substitution of ribose residues and this assumption is supported by the relatively slight reactivity of the purine 2′-O-methyl ribosides in the orcinol color reaction for pentoses. The existence of all of the 16 possible dinucleotides as part of ribonucleate chains has been established. The quantity of alkali-stable trinucleotides is much greater than would be expected for a random spatial distribution of 2′-O-methyl ribosides in ribonucleate chains.
THE PHENOLIC ACIDS IN WHEAT: I. CHANGES DURING GROWTH AND DEVELOPMENT
Authors: El-Basyouni Said , Towers G. H. N.
Published: December 2009

Quantitative determinations were made of p-coumaric, ferulic, caffeic, sinapic, p-hydroxybenzoic, vanillic, and syringic acids which occur as alkali- and acid-hydrolyzable derivatives in ethanolic extracts of wheat tissues. The ethanol-insoluble (cell wall) residues also yielded phenolic acids on cold alkaline hydrolysis. Comparatively large quantities of p-coumaric and ferulic acids (1.8 mg/g dry wt, and 4 mg/g dry wt., respectively, in 25-day-old shoots) were obtained from this fraction, the amounts depending on the age of the tissue. Phenolic acids in the ethanol-soluble fraction reached a maximum concentration about 9 days after germination. The amounts fell off with increasing age, reaching a minimum 4 to 5 weeks later. There was no obvious relationship between the amounts of these acids as reported here and rates of lignification as reported for the wheat plant by others. The behavior of sinapic acid was markedly different from that of p-coumaric and ferulic acids and it is suggested that it may not be a natural precursor of the syringyl units of lignin.
PHOSPHOLIPIDS OF EHRLICH ASCITES TUMOR
Authors: David H. , Rossiter R. J.
Published: December 2009

The following phosphatides (in approximate order of concentration) were studied in cells of the Ehrlich ascites carcinoma incubated in a medium containing inorganic P32: lecithin > sphingomyelin > phosphatidyl ethanolamine = phosphatidyl inositol = phosphatidic acid > choline plasmalogen = phosphatidyl serine > ethanolamine plasmalogen. The specific radioactivity of the diacyl-glycerophosphatide fraction exceeded that of both the plasmalogen and the sphingomyelin – glycerol ether phosphatide fraction, the specific radioactivity of the individual phosphatides being as follows: phosphatidic acid > phosphatidyl inositol > ethanolamine plasmalogen > phosphatidyl ethanolamine = choline plasmalogen = lecithin > sphingomyelin. The microsomal fraction contained more phospholipid, followed by the mitochondrial and nuclear fractions, in that order. The specific radioactivities of the phospholipids of the microsomes and nuclei were greater than that of the mitochondria, chiefly because of the high specific radioactivity of the diacylglycerophosphatide fraction. The high specific radioactivity of the diacylglycerophosphatides was largely the result of a very active incorporation of inorganic P32into phosphatidic acid, particularly in the microsomal fraction. The significance of these findings is discussed.
THE EFFECT OF CORTISOL ADMINISTRATION ON THE ACTIVITIES OF URIDINE AND DEOXYURIDINE PHOSPHORYLASES OF NORMAL AND REGENERATING RAT LIVER
Authors: Yamada Esther W.
Published: December 2009

The phosphorolysis of uridine and deoxyuridine by homogenates of normal and regenerating liver of rats was assayed by a modification of the method of Canellakis (J. Biol. Chem. 227, 701 (1957)). By this assay the Kmvalues for uridine and deoxyuridine were 1.035 × 10−3 M and 2.95 × 10−4 M, respectively. The activities at an arsenate concentration of 0.114 M were 87 to 95% of the activities at an equivalent phosphate concentration.Forty-eight hours after partial hepatectomy the activity of uridine phosphorylase of regenerating liver was 1.1 times that of normal liver, and the activity of deoxyuridine phosphorylase of regenerating liver was 0.75 times that of normal liver. After a single injection of 9 mg of cortisol sodium succinate ester per 100 g of body weight there was a 1.8-fold increase in the activity of uridine phosphorylase but no significant increase in the activity of deoxyuridine phosphorylase of regenerating liver. After a single injection of 9 mg of cortisol per 100 g of body weight into normal rats there was a 1.6-fold increase in the activity of uridine phosphorylase and a 1.4-fold increase in the activity of deoxyuridine phosphorylase of normal liver. Thus, the phosphorolysis of uridine and deoxyuridine increases at different rates in liver after partial hepatectomy, or after cortisol, and this finding lends support to the view of others that the activities are due to two enzymes. The effect of cortisol, whether direct or indirect, in increasing the activities of the two enzymes in normal or regenerating liver would aid in the regulation of concentrations of intermediates of nucleic acid metabolism.
THE USE OF CHROMIUM-51 AS A SENSITIVE QUANTITATIVE CRITERION OF EARLY RADIATION DAMAGE TO RAT THYMOCYTES
Authors: Scaife J. F. , Vittorio P. V.
Published: December 2009

The uptake of Cr61-chromate by thymocytes in suspension can be used as a sensitive quantitative criterion for the evaluation of early radiation damage to these cells, often under situations where other methods of assessing cell death such as morphological changes do not yield valid results. The development of a radiation lesion is characterized by a reduction in the uptake of Cr51, which in vitro can be detected 1 hour following irradiation and with doses as low as 25 rads. By means of this technique thymocytes have been shown to be completely protected by anoxia to doses of up to 150 rads, but at higher levels anoxia affords little protection. No protection of thymocytes could be demonstrated in vivo with S,β-aminoethylisothiouronium bromide hydrobromide (AET) or serotonin at 0.72 mmoles per kg. L-Cysteine, cysteamine, and serotonin at 1 mM concentration in vitro showed no protection of thymocytes provided they were removed from the cells immediately subsequent to irradiation.
POLYSACCHARIDE-PEPTIDE COMPLEXES FROM SERRATIA MARCESCENS CELLS
Authors: Creech Hugh J. , Breuninger Evelyn R. , Adams G. A.
Published: December 2009

Determinations were made of the chemical composition and antitumor properties of several polysaccharide fractions obtained by high speed centrifugation of aqueous extracts of the cells of Serratia marcescens following phenol extraction and trypsin digestion. The use of methods that ensured complete removal of lipid gave polysaccharides containing firmly bound amino acid residues. These were highly effective in causing complete regression of well established solid tumors in mice. The products derived primarily from the cell wall were more potent than the polysaccharides of extracellular and cytoplasmic origins. Extensive differences were also noted in the chemical composition of the polysaccharide complexes isolated from the two sources.
THE EFFECT OF GLUCOSE ON THE DEVELOPMENT OF RESPIRATION BY ANAEROBICALLY GROWN YEAST
Authors: Tustanoff E. R. , Bartley W.
Published: December 2009

Yeast cells grown anaerobically on glucose supplemented with yeast extract, hydrolyzed casein, and oleic acid developed a respiratory capacity on exposure to air. The time course of development of respiration was characteristic with an abrupt onset of oxygen consumption. The magnitude of the uptake of oxygen and the kinetics of its onset were determined by the concentration of glucose to which the yeast was exposed during growth and by the relative amounts of glucose and yeast present during the time of adaptation. A source of amino acids was necessary during the time of adaptation for the consistent development of respiration. Under the growth conditions used, adaptive development of respiration occurred most efficiently when the cells were harvested immediately prior to the onset of the stationary phase. Cytochrome oxidase was virtually absent from the anaerobically grown cells. The kinetics of its adaptive formation were not the same as those for the development of respiration. Cytochrome oxidase appeared before respiration became appreciable. When these anaerobically grown yeast cells were added to the adaptation medium there was a burst of gas output. The identity of the gas is unknown but it is likely to be CO2, H2S, or H2. The role of glucose and other factors in the adaptive development of respiration in yeast is discussed.
STUDIES ON THE LIVETINS OF HEN'S EGG YOLK: I. IDENTIFICATION OF PAPER-ELECTROPHORETIC AND IMMUNOELECTRO-PHORETIC LIVETIN FRACTIONS WITH SERUM PROTEIN ANTIGENS BY IMMUNOELECTROPHORETIC ANALYSIS
Authors: Mok Chi-Ching , Common R. H.
Published: December 2009

Immunoelectrophoretic analysis of an egg yolk livetin preparation has demonstrated the presence of six distinct fractions, which were numbered 1, 2, 3, 4, 5, and 6 from the anodic end of the electropherogram. Four of these fractions have been identified with four livetin fractions obtained by paper electrophoresis as follows: immunoelectrophoretic fraction 1 with alpha-livetin, fraction 2 with beta-livetin, fraction 4 with gamma1-livetin, and fraction 5 with gamma2-livetin.Immunoelectrophoresis of hen serum or cock serum against antilivetin serum has shown that both hen and cock sera contain antigens electrophoretically and immunologically identical to alpha-, beta-, gamma1-, and gamma2-livetins.
AMMONIUM OXIDATION BY CELL-FREE EXTRACTS OF ASPERGILLUS WENTII
Authors: Aleem M. I. H. , Lees H. , Lyric R.
Published: December 2009

Cell-free extracts of Aspergillus wentii were found to catalyze the oxidation of ammonium to nitrate; small quantities of hydroxylamine and nitrite accumulated during the oxidation. The oxidations of hydroxylamine to nitrite and of nitrite to nitrate apparently took place through the respective cytochrome c reductases. Added nicotinamide adenine dinucleotide phosphate and mammalian cytochrome c stimulated the oxidations of ammonium, hydroxylamine, and nitrite. Added iron increased the rate of nitrate formation from ammonium. Allylthiourea did not inhibit ammonium oxidation. The similarities and differences between autotrophic and heterotrophic nitrification are discussed.