bluuebunny/crossref_metadata_2025 huggingface dataset:
MELANIN PIGMENTATION IN BOVINE PINEAL GLAND AND ITS POSSIBLE CORRELATION WITH GONADAL FUNCTION
Authors: Santamarina Enrique
Published: December 2009

The incidence of melanin in the bovine pineal gland was studied in 880 glands. Spectrophotometric analysis and chemical and cytochemical methods identified the black pigment present in the bovine pineal gland as melanin. No melanin was found in bulls 4 and 5 years of age nor in heifers of about 18 months. In pregnant cows over 5 years of age melanin was found in 5.4% of the pineal glands. Non-pregnant cows of the same age exhibited melanin in 8.5% of the pineal glands. Castrated male cattle between 18 and 24 months of age showed 49.6% of the pineal glands with macroscopical signs of melanization. As much as 67% of the pineal glands of steers from some herds contained melanin. In intact cattle melanin in the pineal appears to be mainly an aging phenomenon. The fact that castration in male cattle causes hypertrophy of the pineal gland followed by a degenerative process in which melanin is involved seems to give strong evidence of a pineal gonadal interrelationship. The possible role of the hormones in the phenomenon of melanin formation is discussed.
ACETATE UTILIZATION BY LIVER AND ADIPOSE TISSUE OF RATS FASTED IN THE COLD
Authors: Perry William F.
Published: December 2009

The in vitro incorporation of 1-C14and 2-C14acetate into fatty acids and carbon dioxide by liver and adipose tissue was studied in rats fasted at 5 °C. for 24 hours. Compared with fed rats at room temperature, there was a marked decrease in the incorporation of the acetate carbons into fatty acids and carbon dioxide by liver tissue. A pronounced decrease in acetate incorporation into fatty acid was also noted with adipose tissue from these same animals, but only a slight decrease in incorporation into carbon dioxide. Addition of glucose to the incubation medium caused increases in fatty acid formation by liver and adipose tissue from both normal and fasted animals, but glucose supplementation, while increasing the incorporation of acetate into carbon dioxide by liver tissue from cold fasted rats, did not affect carbon dioxide production by liver tissue from normal animals. Incorporation of acetate into carbon dioxide by adipose tissue was unaffected by glucose supplementation with tissue from both normal and cold fasted rats.
PURIFICATION AND PROPERTIES OF 2,5-DIKETOGLUCONIC ACID DECARBOXYLASE
Authors: Datta A. G. , Hochster R. M. , Katznelson H.
Published: December 2009

2,5-Diketogluconic acid decarboxylase has been purified from extracts of Acetobacter melanogenum. This paper reports the method of purification, the properties of the purified enzyme, and some properties of the reaction product. A crystalline o-nitrophenylhydrazone derivative of the decarboxylation product has been obtained.
THE EFFECT OF MUSCULAR EXERCISE ON PLASMA SODIUM AND POTASSIUM IN THE RAT
Authors: Sréter F. A. , Friedman Sydney M.
Published: December 2009

After running a distance of 100 meters in 7 minutes, untrained rats showed a rise in plasma potassium and a fall in plasma sodium as measured in tail vein samples. These changes are in accord with in vitro observations of the effects of exercise on isolated muscle preparations and similarly are taken to indicate a gain of sodium and a loss of potassium by the exercised muscles in the whole animal. Within 10 minutes of completion of the exercise, plasma sodium concentration was restored to normal while potassium was restored within 20 minutes. Exercise was accompanied by a fall in haematocrit, which remained low for up to 40 minutes. A period of 2 months of preliminary training modified the response to exercise. In these trained animals, a fall in sodium concentration occurred as before but the rise in potassium concentration was less in degree and the haematocrit did not change. It is suggested that the rate of increase of plasma potassium is an index of muscle efficiency while the height of plasma potassium is correlated with the fatigue limit of exercise.
FURTHER TOXICOLOGICAL AND BIOCHEMICAL STUDIES ON ω-FLUORO COMPOUNDS
Authors: Walker I. G. , Parker J. M.
Published: December 2009

The toxicity to mice of the 5-fluoroamyl halides and six 1-fluoroalkanes (C6–C11) is reported. Unlike the other odd-numbered ω-fluoroalkyl halides the 5-membered compounds are quite toxic. In the 1-fluoroalkane series as in other ω-fluoro series the even-numbered compounds are the more toxic. The 5-fluoroamyl halides and 9-fluorononyl chloride, injected into mice in doses of three to four times the LD50, induce an increase in the citrate content of the kidneys between 20 and 90 minutes after injection. For the even-numbered ω-fluoro compounds, a pronounced accumulation has already developed by 20 minutes. Both the even and odd-numbered 1-fluoroalkanes cause an increase in the citrate content of the kidneys of mice injected with them. However, the former compounds promote a more rapid elevation of the citrate content. Other representative odd-numbered ω-fluoro compounds were tested for their ability to cause citrate accumulation at a time greater than 20 minutes. The lack of effect of these compounds on kidney citrate at this later time suggested that among the odd-numbered ω-fluoro compounds the ability to promote such a citrate accumulation is peculiar to the ω-fluoroalkyl halides and the 1-fluoroalkanes.
SEPARATION AND CHARACTERIZATION OF LIPOVITELLIN FROM HEN EGG YOLK
Authors: Joubert F. J. , Cook W. H.
Published: December 2009

The major sedimenting fraction of egg yolk, which appears to be homogeneous in sodium chloride solutions, has been fractionated into lipovitellin, phosvitin, and γ-livetin. By dissolving egg yolk in 0.4 M magnesium sulphate and diluting to 0.2 M much of the phosvitin is precipitated and further dilution of the supernatant yields lipovitellin, from which most of the γ-livetin and contaminating phosvitin can be removed by further treatment. Separation and recovery of both lipovitellin and phosvitin by this procedure indicate that phosvitin is a separate protein and not an integral part of the lipovitellin molecule. When the sedimenting fraction in egg yolk is dissolved in buffer solutions at pH 9.0, γ-livetin can be resolved ultracentrifugally from the rest of this fraction, but precipitation by dilution, with ammonium sulphate, or with ethanol, failed to separate the components. Evidently lipovitellin as prepared in the past by similar methods has been a mixture of three proteins. Lipovitellin containing about 10% γ-livetin and 20% lipid had a molecular weight of 3.2 × 105and a phosphorus content of 0.49%, about half that previously reported.
THE ACID-SOLUBLE NUCLEOTIDES OF SALMON LIVER
Authors: Tsuyuki H. , Chang Violet M. , Idler D. R.
Published: December 2009

The acid-soluble nucleotides of spring salmon liver have been separated by anion-exchange chromatography at low temperature and characterized. Under these conditions the relatively labile uridine-5′-diphosphate nucleotides of acetylglucosamine, galactose, and glucuronic acid were obtained intact, a fact that is further substantiated by the complete absence of uridine-5′-diphosphate. The occurrence of these uridine diphosphate compounds and the absence of uridine diphosphate glucose is discussed in relation to the previously postulated role of inositol as a carbohydrate storage product. A new peptide-containing nucleotide, succinoadenosine-5′-phosphosulphate (peptide), was found in the fraction which immediately follows adenosine-5′-diphosphate. The parent base of this nucleotide, succinoadenine, was also isolated. The nucleotide pattern is simpler than that reported by other investigators for rat liver and wheat.
HYPERGLYCEMIC ACTION AND TOXICITY OF THE URINE OF SCHIZOPHRENIC PATIENTS
Authors: Moya F. , Dewar J. , MacIntosh M. , Hirsch S. , Townsend R.
Published: December 2009

The findings presented confirm earlier reports in the literature that extracts prepared from the urine of schizophrenic patients have greater hyperglycemic activity than similar preparations from normal subjects. In addition, it has been found that the patients' extracts are quite toxic to the rabbit whereas preparations from normal urine are not.Preliminary studies indicate that extracts from the urine of mental patients other than acute schizophrenics behave like extracts from the urine of normal subjects.
LINGCOD MUSCLE PURINE NUCLEOSIDE PHOSPHORYLASE
Authors: Tarr H. L. A.
Published: December 2009

A purine nucleoside phosphorylase enzyme preparation, which catalyzed the general reaction ribose (deoxyribose) [Formula: see text] nucleoside (deoxynucleoside)+orthophosphate, was isolated from muscles of the lingcod (Ophiodon elongatus). The reaction was found to be about 85% in favor of nucleoside synthesis with 10 μM./ml. concentrations of reactants in the hypoxanthine–inosine system. With similar concentrations of reactants in the guanine–guanosine system the equilibrium was about 75% in favor of nucleoside synthesis, and with considerably higher concentrations of reactants in this system this percentage decreased markedly. Purified preparations were stable for over a year at −20 °C., contained two major protein components (zone electrophoresis and ultracentrifuge data), were rather heat labile, and possessed a maximum activity corresponding to liberation of 32 μM. orthophosphate/mg. protein N/hour. Evidence is given in support of the view that a single enzyme is responsible for the above reaction and that it possesses strict specificity for α-D-ribofuranose 1-phosphate and deoxyribose 1-phosphate. Of a large number of substituted purines investigated, only the following were active: hypoxanthine, xanthine, 6-mercaptopurine, 6-methylpurine, 8-azaguanine, guanine, adenine, and 2, 6-diaminopurine. Methods are given for the preparation, in good yield, of analytically pure dicyclohexylammonium salts of ribose 1-phosphate and deoxyribose 1-phosphate.
THE EFFECTS OF ALIPHATIC ALDEHYDES ON THE RESPIRATION OF RAT BRAIN CORTEX SLICES AND RAT BRAIN MITOCHONDRIA
Authors: Beer C. T. , Quastel J. H.
Published: December 2009

A study has been made of the effects of acetaldehyde and n-valeric aldehyde on the respiration of rat brain cortex slices in the presence and absence of 0.1 M KCl. Acetaldehyde at low concentrations (1–2 mM) brings about a marked inhibition of potassium-stimulated respiration of brain cortex slices. The inhibition by acetaldehyde occurs at 1/200th the concentration at which ethanol produces the same effects. The stimulation of brain respiration due to potassium ions is abolished by acetaldehyde at concentrations that have no observable effect on the unstimulated respiration. Acetaldehyde and n-valeric aldehyde, at equivalent concentrations, have almost equal inhibitory effects on potassium-stimulated rat brain cortex respiration. The inhibitory effects of the aldehydes do not increase sharply with increase of their concentrations, in contrast to the effects of the corresponding alcohols. The aldehydes, in contrast to the corresponding alcohols, inhibit brain mitochondrial respiration as markedly as they inhibit brain cortex respiration. The inhibitory effect of the aldehyde on mitochondrial respiration with pyruvate as substrate is greater in the presence of small quantities of malate than in the absence of malate. The acetaldehyde inhibition is abolished on the addition of DPN. The results obtained with the aldehydes do not support the view that the corresponding alcohols exercise their inhibitive effects on brain respiration by preliminary conversion to the aldehydes. It is suggested that the aldehydes exercise their inhibitory effects on brain respiration by rapid attainment of equilibrium with a constituent of the brain respiratory system associated with a rate-limiting step in the citric acid cycle.
INFLUENCE OF THIAMINE AND TRYPTOPHAN UPON THE TRYPTOPHAN PEROXIDASE–OXIDASE ACTIVITY OF RAT LIVER
Authors: Townsend Edith E. , Sourkes T. L.
Published: December 2009

The possible role of thiamine in the oxidation of tryptophan by tryptophan peroxidase–oxidase (TPO) of liver was studied by several approaches. (1) In acute experiments parenterally administered thiamine did not cause an adaptive increase in the enzyme content of rat liver, as can be induced by similar injection of tryptophan. (2) Thiamine pyrophosphate, added to liver extracts which had been partially inactivated with respect to TPO by aging for one-half hour at 37 °C. or by prolonged dialysis, did not reactivate the enzyme oxidizing tryptophan. (3) In multifactorial dietary experiments in which thiamine, tryptophan, or both were omitted from the diet only tryptophan deficiency resulted in a decrease of the liver TPO activity. There was no effect of thiamine, either in the presence or absence of tryptophan. The D- and L-isomers of tryptophan were equally effective in promoting TPO activity. These results do not support the findings of other authors who imply a role for thiamine in the oxidation of tryptophan by TPO.
THE METABOLISM OF ANIMAL TISSUES CULTIVATED IN VITRO: III. AMINO ACID METABOLISM OF STRAIN L CELLS IN COMPLETELY SYNTHETIC MEDIA
Authors: Pasieka Arthur E. , Morton Helen J. , Morgan Joseph F.
Published: December 2009

Strain L cells, of mouse fibroblastic origin, have been cultivated in vitro in completely synthetic medium M 150 and in various modifications of this medium. The amino acid changes in the nutrient medium during cell cultivation have been studied by paper chromatography. A characteristic pattern of amino acid uptake and accumulation in the medium has been found. No change in the alanine concentration was observed but omission of alanine from the culture medium resulted in its accumulation in appreciable amounts. Omission of glutamic acid did not alter the pattern of amino acid changes by the cells. Omission of glutamine increased the uptake of amino acids and prevented amino acid accumulation. Omission of both glutamic acid and glutamine resulted in a virtual cessation of amino acid changes in the culture medium. Strain L cells decreased the adenine content of the medium and produced small amounts of hypoxanthine. These changes were not affected by alterations in the amino acid content of the medium. Omission of glutamic acid and glutamine from the culture medium did not cause an appreciable decrease in cell population or apparent degeneration of the cultures over a 30-day period.
SMOOTH MUSCLE ELECTROLYTES
Authors: Dantel Edwin E.
Published: December 2009

The sodium, potassium, chloride, and water concentrations have been analyzed in relatively pure smooth muscles of electrophysiological interest and compared to similar analyses of other muscle types. The smooth muscles analyzed included isolated longitudinal myometrium from the uteri of various species and the taenia coli from guinea pigs and rabbits. The lack of accurate measurements of extracellular fluid volume was stressed and various assumptions were made to provide limiting values for this volume. Within these limits, various distributions of the ions studied were calculated. The outstanding feature of the ion distribution was the occurrence of an apparently hyperosmotic concentration of monovalent cation (Na + K) irrespective of its assumed volume of distribution. Evidence was discussed suggesting that this finding should be attributed to cation binding and/or large quantities of polyvalent intracellular anion. Evidence was presented suggesting active potassium uptake and active extrusion of sodium as the mechanisms of distribution of these ions. Chloride distribution was compatible with the assumption of distribution according to its equilibrium potential.
ISOLATION OF A STEROID-LIKE SUBSTANCE FROM URINE AND CITROUS FRUITS
Authors: Nowaczynski Wojciech , Sandor Thomas , Koiw Erich , Jones R. Norman , Genest Jacques
Published: December 2009

The isolation and the partial chemical and physicochemical characterization of a chloroform-soluble substance obtained from human urine and citrous fruit juices are presented. The urinary compound, designated as compound III, is present mostly as a conjugate hydrolyzed by animal β-glucuronidase whereas it is in free form in fruit juices. It is present in the urine of normal males and females and in a number of pathological conditions. Its urinary excretion is significantly increased as a result of diets rich in potassium (250 meq./day). In various paper chromatographic systems, the compound has a mobility similar to that of aldosterone. Detailed study of its chemical and physicochemical characteristics, including oxidative degradation and infrared and elementary analysis, suggests a steroidal or sesquiterpinoidal structure. However, at the present time, the data obtained do not permit the final elucidation of the chemical formula of compound III.
N-TERMINAL AMINO ACIDS OF THE PROTEINS OF THE FLOATING FRACTION OF EGG YOLK
Authors: Smith David B. , Turner K. J.
Published: December 2009

Lysine is the major N-terminal amino acid of both the soluble and insoluble fractions of the floating lipoprotein of hen's egg yolk, which suggests a common primary structure. Several minor components are also present in both fractions.
LACTIC DEHYDROGENASE OF THE MAMMALIAN ERYTHROCYTE: III. THE FORMATION OF A COMPLEX OF THE ENZYME WITH DPN AND LACTATE
Authors: Ottolenghi Paul , Denstedt Orville F.
Published: December 2009

In the transfer of hydrogen ions and electrons from lactate to DPN by lactic dehydrogenase the lactate is capable of forming a complex only with the binary complex of enzyme and coenzyme to form an active ternary complex. The results of kinetic studies indicate that the site for the binding of lactate is on the DPN molecule itself.
DETERMINATION OF GLUCOSE IN FISH BLOOD: A MODIFICATION OF THE FOLIN–MALMROS MICROPROCEDURE
Authors: Murrell Leonard R. , Nace Paul F.
Published: December 2009

A modification of the Folin–Malmros micromethod is described for the determination of fish blood glucose. A more efficient separation of blood proteins is obtained by precipitating 0.1 ml blood in 10.0 ml tungstic acid. This is followed by hot alkaline reduction of ferricyanide, and colorimetric measurement of a Prussian blue – sodium lauryl sulphate suspension. The method, which eliminates certain difficulties found in other procedures, has been successfully applied in more than a thousand analyses of blood from two species of fish (Opsanus and Ictalurus) having glucose concentrations between 15 and 250 mg per cent.
BIOCOLLOIDS IN NORMAL HUMAN URINE: II. PHYSICOCHEMICAL AND IMMUNOCHEMICAL CHARACTERISTICS
Authors: Webb T. , Rose B. , Sehon A. H.
Published: December 2009

The biocolloids of normal urine were separated by electrophoresis on starch and compared with similarly prepared fractions of serum by ultracentrifugal, free diffusion, and immunochemical techniques. The albumin fraction of urine was indistinguishable from the serum component. The urinary γ2-globulins were shown to consist of low molecular weight (10,000) fragments of the normal serum components. The other globulins of the urine were antigenically related to some of the serum components but appeared to contain lower molecular weight materials. Some of the components of normal serum could not be detected in the urine and the urine contained at least two components which were not present in the serum.
STUDIES ON THE PRESERVATION OF BLOOD: VI. THE INFLUENCE OF ADENOSINE AND INOSINE ON THE METABOLISM OF THE ERYTHROCYTE
Authors: Rubinstein David , Kashket Shelby , Denstedt Orville F.
Published: December 2009

Inosine is as effective as adenosine in maintaining the organic phosphate esters in the erythrocytes during storage in the citrate–dextrose preservative medium. Adenosine undergoes deamination in the presence of erythrocytes with liberation of ammonia. The ammonia tends to counteract the increase in the hydrogen ion concentration caused by the glycolytic production of lactic acid. By maintaining the hydrogen ion concentration within the range favorable to the activity of hexokinase, adenosine tends to maintain the utilization of glucose in the preserved red cells. Inosine, on the contrary, does not resist the increase in hydrogen ion concentration of the cells during storage, hence the utilization of glucose rapidly becomes impaired and supplanted by the utilization of ribose derived from the nucleoside. The utilization of ribose remains practically unaffected by the increase in hydrogen ion concentration to pH 6.1. Ammonium ions stimulate the utilization of glucose by erythrocytes but in degree not sufficient to account for the full effect of adenosine.
STUDIES OF LIGNIN BIOSYNTHESIS USING ISOTOPIC CARBON: VII. THE ROLE OFp-HYDROXYPHENYLPYRUVIC ACID
Authors: Brown Stewart A. , Wright D. , Neish A. C.
Published: December 2009

L-Phenylalanine-C14and p-hydroxyphenylpyruvic acid-3-C14were administered to wheat, buckwheat, and salvia (Salvia splendens Sello), and after 24 hours the "lignin aldehydes" (p-hydroxybenzaldehyde, vanillin, and syringaldehyde) were isolated following alkaline nitrobenzene oxidation of the plant fraction insoluble in ethanol–benzene and water. Although all species converted phenylalanine readily to lignin, only wheat could form the syringyl and guaiacyl parts of lignin efficiently from p-hydroxyphenylpyruvic acid. p-Hydroxybenzaldehyde recovered from all species was heavily labelled after feeding both compounds. The L-tyrosine from acid hydrolysis and the p-hydroxybenzaldehyde from nitrobenzene oxidation, isolated from buckwheat activated by feeding p-hydroxyphenylpyruvic acid-3-C14, had the same molar specific activity, and it is considered probable that most if not all of the p-hydroxybenzaldehyde in all these species was derived from protein tyrosine in the extracted residue. When p-hydroxyphenyllactic acid-3-C14was metabolized by wheat all the aldehydes were labelled, but none possessed measurable radioactivity when this compound was administered to buckwheat. Consequently, neither p-hydroxyphenylpyruvic nor p-hydroxyphenyllactic acid is a general intermediate in lignification, and differences noted here and in previous papers between grasses and non-grasses probably result from the unique ability of grasses to convert p-hydroxyphenyllactic acid to p-hydroxycinnamic acid. This idea is supported by the ability of wheat to form p-hydroxycinnamic and ferulic acids readily from both phenylalanine and tyrosine, whereas only phenylalanine is a good precursor of these acids in salvia. A scheme is presented showing the metabolic interconversions of phenylpropanoid acids and related compounds leading to lignin.
SOME EVIDENCE CONCERNING THE MODE OF BINDING OF HISTAMINE
Authors: McIlreath Jr. Fred J.
Published: December 2009

The release of histamine from dog liver particles and isolated perfused cat paws was induced by various histamine liberators in both isotonic and hypertonic solutions of sucrose and mannitol. When any of several base-type histamine liberators were employed, significantly less histamine was discharged from the preparations in 1.2 M solutions than in isotonic solutions (0.32 M). No significant differences were found when surface-active compounds were used as liberators.
ÉTUDE DE LA RÉACTION DE L'ADRÉNALINE AVEC L'ÉTHYLÈNEDIAMINE
Authors: Nadeau Guy , Joly Louis-Philippe
Published: December 2009

The influence of pH, reagent composition, time, temperature, light, and various ions, on the reaction of fluorescence between adrenaline and ethylenediamine, has been investigated. The necessity of a preliminary oxidation to adrenochrome is confirmed. Optimum pH of reaction is situated at 10.4 ± 0.1, while extraction with isobutanol is best performed at pH 10.1 ± 0.1. A satisfactory reagent is one that contains 114.5 millimoles of ethylenediamine base per 100 ml of reacting mixture and sufficient hydrochloric acid to bring the pH to 10.3 ± 0.1. Temperature and length of reaction may be conveniently set at 50 °C and 20 to 30 minutes. Increasing the temperature significantly lowers the yield of fluorescent material; performing the reaction at room temperature increases the yield, but lengthens the procedure. Exposure to diffuse and ultraviolet light also affects the yield of fluorescence. All these factors (temperature, light, as well as excess of oxygen) appear to exert their influence in the first stages of the reaction, since the fluorescent material, once formed, is relatively stable. The beneficial effect of various ions, including Cu++, Al+++, and MoO4−−, is discussed in relation to complex formation. Efficiency of extraction with aliphatic alcohols has also been investigated; true yield from C14-adrenaline is estimated. In the light of recent findings on the structure of adrenochrome, new pathways for the reaction are suggested.
THE SITES OF TRANSFER OF SODIUM, POTASSIUM, AND IODIDE IN THE PAROTID DUCT SYSTEM OF THE DOG
Authors: Burgen A. S. V. , Terroux K. Godwin , Gonder E.
Published: December 2009

Rapid intra-arterial injections of radioactive iodide, sodium, and potassium have been made into the carotid artery while the parotid gland was secreting saliva at a steady rate. All three ions appeared in the saliva within a few seconds with iodide lagging slightly behind sodium and potassium. The curve for potassium was several times as long as those for sodium and iodide. With intravenous injections of the isotopes, after sufficient time had been allowed for equilibration between the blood and the parotid gland, there was an initial transient concentration of all three ions when secretion started after a rest period. The transient concentrations for sodium and potassium appeared slightly ahead of that for iodide. Potassium showed a clear second phase in its rest transient concentration.It is concluded that all three ions are able to cross the salivary duct epithelium and enter the saliva. Evidence for active transfer of potassium into the salivary duct lumen is presented.
COMPARISON BETWEEN SEASONAL AND THERMAL ACCLIMATION IN WHITE RATS: I. METABOLIC AND INSULATIVE CHANGES
Authors: Héroux O. , Depocas F. , Hart J. S.
Published: December 2009

Physiological adjustments to cold temperature have been compared in white rats exposed either to the outdoor fluctuating environmental conditions or to the indoor constant temperature conditions. While the metabolic adjustments such as increased peak metabolism and decreased shivering were similar in outdoor and indoor rats exposed to cold, the adjustments in insulation and thermoneutral metabolic rates were quite different. The pelage insulation increased in the rats kept outside during the winter but remained unchanged in the rats kept in a constant temperature room maintained at 6 °C. The resting metabolic rate measured at 30 °C increased in the 6 °C acclimated rats but not in the winter-exposed animals. Over the temperature range +30 °C to −15 °C, while the indoor cold-acclimated rats had a higher metabolic rate than their controls acclimated to 30 °C, the winter rats had a lower metabolism than their summer controls.
THE EFFECT OF UNSATURATION OF DIETARY FAT AND OF ANTIOXIDANTS ON THE DEVELOPMENT OF LIVER DAMAGE
Authors: Valberg L. S. , Young Rose A. , Beveridge J. M. R.
Published: December 2009

The addition of unsaturated fatty acids, even in small amounts, to diets low in vitamin E, selenium, and the sulphur-containing amino acids greatly accelerated the development of acute liver necrosis in rats. The production of this lesion was shown also to be affected in a similar manner by the nature of the dietary fat in the ration consumed immediately prior to the removal of protective substances such as the sulphur-containing amino acids; unsaturated fatty acids or lipid again acted as predisposing factors.Gamma-tocopherol incorporated in the diet at a level of 0.02% and injected at a level of 1.5 mg/rat/day was equally as effective as alpha-tocopherol in preventing liver necrosis. The protective effect of gamma-tocopherol against the development of liver necrosis lends support to the thesis that alpha-tocopherol protects against liver damage by virtue of its antioxidant activity.
STUDIES ON WHEAT PLANTS USING CARBON-14 COMPOUNDS: IX. RADIOACTIVITY OF WHEAT FOLLOWING INJECTION OF FORMATE-C14AND GLYCINE-1-C14WITH SPECIAL REFERENCE TO SERINE LABELLING
Authors: McConnell W. B. , Bilinski E.
Published: December 2009

Formate-C14and glycine-1-C14were injected into the stems of wheat plants 71 days after seeding and the distribution of carbon-14 in the plants 102 days after seeding (full maturity) was studied. Large losses of formate carbon from the plant were observed. The most active kernel component isolated after formate-C14injection was protein, the methyl carbon of the methionine and carbon-3 of serine being especially radioactive. The gluten protein of wheat kernels labelled with glycine-1-C14was also comparatively radioactive, more than one half of the carbon-14 occurring in the carboxyl carbons of glycine and serine. The results suggest that the radioactive serine was formed largely by way of the condensation of formate, or a "one carbon fragment," with carbon-2 of glycine.
RELATIVE PRODUCTION OF FLUORESCENT AND UV-ABSORBING STEROIDS BY INCUBATED RAT ADRENAL GLANDS
Authors: Fortier Ciaude
Published: December 2009

Silber's fluorometric method for corticosteroids was used concurrently with Saffran's UV-absorption method for Δ 4-3-keto-steroids to determine the relative production of fluorescent and UV-absorbing compounds by incubated rat adrenal glands, in the presence or absence of ACTH. The production of both types was markedly increased by ACTH. The F/UV ratio, close to unity after 15 minutes of incubation with or without ACTH, decreased to values of 0.51 for non-stimulated, and 0.62 for stimulated glands, after 2 hours. The similarity of these values with the red./UV ratios, observed by Elliott et al. under comparable conditions, suggests that the compounds determined by fluorometry correspond to the blue tetrazolium-reducing steroids with α-ketolic side chains, characterized by these investigators. The nature of these steroids, and of the UV-absorbing, non-reducing, non-fluorescent material is discussed in the light of chromatographic findings. Concurrent assays of rat pituitary extracts by the UV-absorption and fluorometric methods, in Saffran and Schally's adrenal incubation system, yielded comparable results.
ACCLIMATIZATION TO COLD: OBSERVATIONS ON THE MECHANISM OF THE REDUCED IMMEDIATE ADRENAL RESPONSE
Authors: Nicholls Doris , Molloy Rosemary , Stavraky Kathleen , Rossiter R. J.
Published: December 2009

The incorporation of inorganic phosphorus labelled with P32 into the inorganic phosphorus of the adrenal gland was measured in rats acclimatized to cold for 4 weeks. Previously it was reported that the immediate pituitary–adrenal response to brief cold exposure (2 hours at −5 °C), as judged by the increased P32 incorporation is considerably decreased in rats that have been acclimatized. Some observations are now reported on the mechanism of this reduced immediate response.The administration of ACTH, pitressin, or adrenaline caused similar increases in the adrenal phosphorus metabolism in acclimatized and non-acclimatized control rats. Acclimatization could still be demonstrated in rats after the fur had been removed by clipping.From these results it is concluded that the decreased immediate pituitary–adrenal response to an exposure to more severe cold, observed in acclimatized rats, is not the result of an increased fur thickness, nor is it the result of a decreased sensitivity of the adrenal tissue to ACTH, or to a decreased sensitivity of the pituitary or hypothalamus to a given stimulus. It is suggested that the reduction in the immediate pituitary–adrenal response to a more severe cold stress in acclimatized rats might be due to an alteration in the sensitivity of the peripheral nerve receptors, or in the mechanism, nervous or otherwise, whereby the pituitary is stimulated.
ON THE INDUCED SYNTHESIS OF AN ENZYME REQUIRED FOR BIOSYNTHESIS OF AN ESSENTIAL METABOLITE: INDUCED KYNURENINASE SYNTHESIS IN NEUROSPORA CRASSA
Authors: Wainwright S. D. , Bonner D. M.
Published: December 2009

Brief incubation of washed mycelial pads of Neurospora crassa with L-tryptophan or L-kynurenine caused a marked and rapid increase in kynureninase activity. Some of the factors affecting the extent of enzyme formation were studied. Tryptophan was almost as effective an inducer of kynureninase formation as kynurenine. The significance of induced kynureninase formation as a regulator of niacin biosynthesis is discussed.
A COMPARATIVE STUDY OF NUCLEOTIDE METABOLISM IN FISH LIVER
Authors: Forrest R. J. , Hansen R. G.
Published: December 2009

Anion exchange chromatography has been used to separate the acid-soluble nucleotides of the livers of several species of fish including salmon taken in fresh and salt water. This technique has produced an elution pattern of nucleotides similar to that obtained from poultry and mammalian liver. Two of the uridine-containing areas eluted from the column have been investigated in detail using enzymatic, chromatographic, and colorimetric techniques. The first of these two adjacent peaks was found to contain N-acetylglucosamine and N-acetylgalactosamine, whereas the second contained glucose and galactose. In both cases, the glucose moiety was the major constituent.Samples of liver taken from silver salmon were fractionated and two of the enzymes acting on UDP glucose were identified. The first of these enzymes, UDPG dehydrogenase, was partially purified and the product of the reaction with UDPG was identified as UDP glucuronic acid. The second enzyme, UDPGal-4-epimerase, was separated from the dehydrogenase and characterized by enzymatic assay using UDP galactose as substrate.
SOME PROPERTIES OF THROMBIN PREPARATIONS
Authors: Seegers Walter H. , Casillas Gerardo , Shepard Robert S. , Thomas William R. , Halick Paul
Published: December 2009

Bio-resin thrombin preparations were found to contain three weak precipitinogens. The clotting activity was not demonstrably associated with the precipitinogenic systems. Further, work was done on methods for the purification of citrate resin thrombin, and its clotting activity is also not associated with a precipitinogenic system. The N-terminal amino acid of both bio-resin thrombin and citrate resin thrombin was found to be glutamic acid. The two preparations were found to be homogeneous upon ultracentrifugal examination and could not be differentiated on the basis of sedimentation constants. Since "citrate" activation and "bio" activation produce eventually similar thrombin material, the autocatalytic activation of prothrombin in 25% sodium citrate solution can be used as an ideal model of prothrombin activation. The prothrombin first dissociates to form a derivative that does not form thrombin in the two-stage analytical reagents. Then a second alteration occurs in which the derivative again may form thrombin in the two-stage analytical reagents. Then thrombin activity appears as esterase activity, then as clotting activity. Later the clotting activity may be lost and finally also the esterase activity. The original prothrombin is a precipitinogen while the active thrombin is not.
ON THE ANTIGENICITY OF INSULIN: FLOCCULATION OF INSULIN-ANTIINSULIN
Authors: Moloney P. J. , Aprile M. A.
Published: December 2009

Serum from a horse which had received a series of injections of crystalline ox insulin showed typical flocculation with a solution of crystalline ox and pig insulins and with crude insulin extracted from the pancreas of the rabbit, horse, monkey, whale, and human. Flocculation was due to insulin and its corresponding antibody, since both insulin and antiinsulin, measured by mouse convulsion test, could be recovered from floccules. The ratio of insulin antibody to insulin (equivalence zone) is in the order of 497 to 553 micrograms per unit of insulin (40 μg). This corresponds to a molecular ratio of antibody: insulin of 3:1.
INHIBITION OF THE ESTERATIC ACTIVITY OF THROMBIN BY SARIN AND TABUN
Authors: Shuster J. , Scaife J. F. , Grant G. A.
Published: December 2009

Isopropyl methylphosphonofluoridate (sarin) and ethyl N,N-dimethylphosphoramidocyanidate (tabun) have been found to inhibit the esteratic activity of thrombin towards the substrate p-toluenesulphonyl-L-arginine methyl ester. The rate of inhibition is markedly dependent on pH and is greatest in alkaline solutions. At pH 7.8 and 25 °C, the specific rate for inhibition by tabun at a concentration of 6.17 × 10−4 M is 0.0271 minutes−1and for sarin at a concentration of 7.15 × 10−5 M it is 0.0232 minutes−1. Thrombin which is completely inhibited by sarin could not be reactivated by use of oximes at pH 9 and concentrations of 0.02 M.
ANOMALOUS RESULTS IN THE PERIODIC ACID OXIDATION OF SERINE
Authors: Mortimer D. C.
Published: December 2009

When serine-3-C14was degraded with periodate at pH 5.5, the expected molar equivalents of carbon dioxide (carbon-1), formic acid (carbon-2), and formaldehyde (carbon-3) were obtained, but 15 to 31% of the C14was recovered in the formic acid and the specific activity of the formaldehyde was reduced by a similar amount. These results combined with additional evidence from periodic acid uptake curves at different pH values, and the identification of glycolaldehyde isolated as the dinitrophenylhydrazone from the reaction mixture, showed that the serine–periodate reaction was more complex than has been assumed. A modification of the accepted mechanism was proposed to account for the anomalous results.
PURIFICATION AND PROPERTIES OF PHOSPHOGLUCOSE ISOMERASE FROM ASPERGILLUS NIGER
Authors: Singh Kartar
Published: December 2009

Phosphoglucose isomerase from Aspergillus niger was purified about fiftyfold by ammonium sulphate fractionation and treatment with calcium phosphate gel. The properties and kinetics of the enzyme are described. The enzyme resembled the muscle phosphoglucose isomerase in not requiring metal ions for activation but differed in showing no inhibition with phosphate. The enzyme showed maximum activity between pH 7.8 to 8.0 as compared with the optimum pH 9.0 shown by the muscle enzyme.
BIOCHEMICAL STUDIES ON SOCKEYE SALMON DURING SPAWNING MIGRATION: VII. STEROID HORMONES IN PLASMA
Authors: Idler D. R. , Ronald A. P. , Schmidt P. J.
Published: December 2009

Cortisone, cortisol, and 17-hydroxyprogesterone were isolated from the plasma of prespawning Fraser River sockeye salmon. The female plasma contained double the concentration of cortisone and cortisol found in male plasma, 41 μg and 26 μg/100 ml respectively as compared with 22 μg and 11 μg/100 ml.Corticosterone is probably present at a very low concentration and neither 11-desoxycorticosterone nor aldosterone was detected in the plasma from approximately 100 fish. Cortisone, cortisol, and total 17-hydroxysteroids were quantitatively determined in plasma samples obtained from two pure races of sockeye captured at various stages of sexual maturity. The combined concentration of cortisone and cortisol which, at the mouth of the river was three times that of the normal human, increased to as high as 17 times this level following spawning. The results are discussed in relation to the death of the fish.
EFFECTS OF GROWTH HORMONE ON METABOLIC AND ENDOCRINE FACTORS IN HYPOPHYSECTOMIZED DOGS
Authors: Campbell James , Chaikof Leo , Wrenshall Gerald A. , Zemel Reuben
Published: December 2009

Hypophysectomy in dogs caused reductions in: the level of sugar in the blood; the volume % of packed red blood corpuscles; the rate of clearance of bromsulphthalein; the weight of the pancreas; the amount of insulin extractable from the pancreas; and the weights of the kidneys, heart, and adrenal glands. The glucose tolerance of hypophysectomized dogs was significantly less than that of normal dogs.The administration of growth hormone during 5 days to hypophysectomized dogs caused: increase of blood sugar but not to diabetic levels; elevation and prolongation of the glucose tolerance curve; increased erythrocyte sedimentation rate; reduced volume % of red blood corpuscles; restoration of bromsulphthalein clearance to normal; reduction of the insulin extractable from the pancreas to 60% of the pretreatment level; increases in the weight, total lipid, dry fat-free residue, and water of the liver; and restoration of the kidney weight and lipid content to normal. Little or no glycosuria or ketonuria and no anorexia occurred under these conditions.The same treatment of normal dogs with growth hormone caused: increase of blood sugar to diabetic levels; elevation and prolongation of the glucose tolerance curve; increased erythrocyte sedimentation rate; decreased volume % of packed red blood corpuscles, glycosuria, ketonuria, albuminuria, and anorexia; great decrease in the amount of insulin extractable from the pancreas to 6% normal; increase in the total lipid, dry fat-free residue, and water of the liver, increase in the weight and lipid of the kidney; and increase in the weight of the ventricles of the heart. The bromsulphthalein clearance was not altered. The physiological significance of these findings is discussed, particularly the production by growth hormone of more pronounced diabetes and greater reduction of insulin extractable from the pancreas in normal than in hypophysectomized dogs.
THE ISOLATION, IDENTIFICATION, AND PROPERTIES OF DINUCLEOTIDES FROM ALKALI HYDROLYZATES OF RIBONUCLEIC ACIDS
Authors: Lane B. G. , Butler G. C.
Published: December 2009

The isolation, identification, and properties of dinucleotides from alkali hydrolyzates of RNA are described. Preparative methods for obtaining the alkali-labile dinucleotides which were found in our 18-hour hydrolyzates of RNA in 1 M potassium hydroxide are described, and it is noted that all of them (ApAp, ApGp, ApUp, GpAp, and GpCp) are not susceptible to pancreatic ribonuclease at the concentrations of the enzyme which are customarily employed for hydrolytic degradations. It has been found, however, that two of these dinucleotides (ApAp and ApUp) are susceptible to pancreatic ribonuclease at concentrations of the enzyme which are about five thousand times greater than those customarily employed. The rate constants of first order hydrolysis in alkali of ApAp, ApGp, ApUp, GpAp, and GpCp are found to be correspondingly lower than the rate constants for two dinucleotides which were not found in our 18-hour hydrolyzates, and which are susceptible to pancreatic ribonuclease. Furthermore, it is reported that the eight possible diribonucleotides which are not susceptible to pancreatic ribonuclease (ApAp, ApGp, ApCp, ApUp, GpGp, GpAp, GpCp, and GpUp) are found in roughly equivalent amounts in a 2-hour alkali hydrolyzate of a preparation of yeast RNA, and account for 80–90% of the dinucleotides present.In addition to the alkali-labile dinucleotides found in alkali hydrolyzates of RNA, the isolation and preliminary characterization of five alkali-stable compounds are reported.
THE SELECTIVE PROTEOLYTIC ENZYME INHIBITORY ACTION OF BENZETHONIUM CHLORIDE
Authors: Beck Ivan T. , Pinter E. , McKenna R. D. , Griff H.
Published: December 2009

Acute hemorrhagic pancreatitis in humans is thought to be perpetuated by the autolytic processes catalyzed by trypsin and lipase. This study is an integral part of our search for trypsin and lipase inhibitors to be used in the treatment of this disease.Benzethonium chloride was found to inhibit tryptic activity in vitro. The proteolytic activity of rabbit's serum was inhibited, and the inhibition was most pronounced 6 to 12 hours after the subcutaneous injection of the compound. Fibrinolysin was also inhibited in vitro but benzethonium chloride had no inhibitory action on chymotrypsin, pepsin, or lipase.Serum proteins in vitro were precipitated only with very high concentrations of the compound. No significant protein changes were observed in sera of rabbits after the subcutaneous injection of the compound.
THE TAC METHOD OF TRYPTIC ENZYME ACTIVITY DETERMINATION
Authors: Ronwin Edward
Published: December 2009

A new, practical, and quantitative method for the determination of tryptic enzyme activity is reported. The method is based on measurements of the U.V. absorption of the complex formed between cupric ion and Nα-p-toluenesulphonyl-L-arginine, the latter being the product of the reaction between the tryptic enzymes (thrombin, trypsin, plasmin) and the corresponding methyl ester. Comparisons with the null point titration procedure demonstrate the new method's superiority when dealing with enzyme–substrate reactions in concentrated buffer solutions. Under certain conditions, it could also be superior in dilute buffer situations. The effects of pH and cupric ion concentration on complex formation are discussed along with other characteristics of the U.V. absorption curves of the complex.
THE PAPER CHROMATOGRAPHIC FRACTIONATION OF PLANT STERYL ESTERS
Authors: Kuksis A. , Beveridge J. M. R.
Published: December 2009

The even-numbered C2–C22saturated and the C18-unsaturated fatty acid esters of beta- and gamma-sitosterol, stiginasterol, ergosterol, stigmastanol, and gamma-sitostanol were used separately and in model mixtures for the evaluation of existing and the development of new paper chromatographic methods for the separation and identification of these compounds. Satisfactory separations of the esters were obtained by the ascending reversed phase chromatography on cellulose or glass fiber paper using one of the following systems depending upon the number of carbon atoms in the fatty acid moiety of the ester: C2–C12, aqueous acetic acid/chloroform/paraffin oil; C8–C18, aqueous propionic acid/paraffin oil; C8–C22, acidified aqueous methanol/chloroform/paraffin oil or aqueous butyric acid/paraffin oil. The rate of migration of the esters was inversely proportional to the molecular weight and was increased by the introduction of unsaturation.The increased movement due to unsaturation has been correlated with the number of ethylenic hydrogens, and the possibility that polarity of these atoms might account for this phenomenon is discussed. The reversed phase paper partition chromatography of sterols as their esters is suggested as a potential tool for evaluation of polarity of the various attributes of the sterol nucleus in terms of the chain length of the ester fatty acid. The rule of independent contributions of the constituents of a molecule to its distribution isotherm was observed not to hold in this fatty ester series.
MITOTIC RATE IN THE EPIDERMIS OF WARM- AND COLD-ACCLIMATED RATS
Authors: Héroux O.
Published: December 2009

The effect of the environmental, temperature on the mitotic activity in the skin of warm- and cold-acclimated rats was estimated with the colchicine method. On rats kept at 30 °C for 3 months, the skin temperature was found to vary from 30.4 °C on the ear, to 35.3 °C on the back. Least-square linear relationships were established between log induction rate (rate at which cells start division), log mitotic duration, and tissue temperature. The colder the epithelium, the lower was the induction rate and the longer was the mitotic duration. Depending on their temperature, the different epithelia studied could be classified as far as their mitotic activity was concerned, in the following decreasing order: duodenum, back, tail, foot, and ear. For a 7 °C difference in temperature between duodenum and ear, there was a sevenfold difference in mitotic duration, which reveals an unusual Q10 of 10.The data obtained on similar epithelial tissues of cold-acclimated rats supplied some evidence of adaptation in the mitotic rate of the back skin. In the ear, foot, and tail skin the colchicine method failed to give quantitative data because mitosis was proceeding too slowly. It even failed in rats maintained in the cold for 118 days. When this finding is considered together with the observations reported previously that after 3 weeks of cold exposure, mitotic activity in the ear is resumed, after having been stopped almost completely, it appears that the adaptation that has taken place in this cold tissue is one that allows the cells to overcome the mitotic blocking effect of cold but not one which allows mitosis to proceed at a much faster rate than would be indicated by the Q10 observed on the epithelia of the "30 °C rats".