bluuebunny/crossref_metadata_2025 huggingface dataset:
THE STANDARDIZATION OF STRESS IN THE PRODUCTION OF HEMORRHAGIC SHOCK: THE RELATION OF THE DURATION OF STRAIN AND THE RESISTANCE OF THE ANIMAL TO THE ONSET OF IRREVERSIBLE SHOCK
Authors: Lansing A. M. , Stevenson J. A. F.
Published: October 2017

When hemorrhagic shock is produced by bleeding from an artery into a reservoir at a height fixed to provide a constant level of hypotension, compensatory vasoconstriction eventually fails and the blood in the reservoir spontaneously reinfuses into the animal. The value of the onset of this spontaneous reinfusion as a criterion for the production of a standardized and irreversible hemorrhagic shock has been investigated in the rat. The animal was bled into the reservoir until the arterial pressure fell to 30 mm. Hg, which was maintained until a reduction of the volume of blood in the reservoir at three successive 2-minute intervals signified that spontaneous reinfusion had just begun. Reinfusion of the remainder of the blood was quickly completed by raising the reservoir. The animal was observed for 48 hours.A good correlation between the volume of blood forced into the reservoir early in hypotension and the duration of hypotension until the occurrence of spontaneous reinfusion was observed. With a regression equation of time (expressed as percentage of the total hypotensive period) against the volume of blood in the reservoir at various times it was possible to predict from early bleeding volumes, with fair accuracy, the duration of hypotension necessary to produce spontaneous reinfusion. In general, animals forcibly reinfused before this predicted spontaneous reinfusion survived while those exposed to the total duration died. Spontaneous reinfusion under these conditions appears to be closely associated in time with the onset of irreversible shock. The prediction from early bleeding volumes of duration to spontaneous reinfusion should permit the determination of the effect of various treatments on the resistance to hemorrhagic hypotension without the necessity for sacrifice of the animal.
EFFECTS OF OVARIAN HORMONES ON THE CONTENT AND DISTRIBUTION OF CATION IN INTACT AND EXTRACTED RABBIT AND CAT UTERUS
Authors: Daniel Edwin E. , Daniel Betty N.
Published: October 2017

The uteri of rabbits and cats have been analyzed for sodium, potassium, and chloride, usually after various preliminary treatments with estrogen and progesterone. These tissues contain less potassium (50–80 meq./kg.) than striate muscle and more sodium (75–118 meq./kg.) than other highly cellular tissues. It appears that this cation composition can be attributed in part to a relatively large extracellular fluid volume (EFV).Various methods have been used to estimate the EFV in these tissues. The radiosulphate space (in vitro) does not appear to be reliable as a measure of extracellular space. The chloride space varies, but exceeds 400 ml./kg. in all cases, and in some approaches 700 ml./kg. Inulin space (in vitro) is about 60% of the chloride space, which in turn is usually smaller than the sodium space. The chloride space appears to provide the best approximation to the EFV since its volume of distribution rarely exceeds the sodium space, and since chloride (but not sodium) can be removed completely on leaching in isotonic sucrose.Calculated cellular potassium concentrations are as high as or higher (150–210 meq./l.) than in striate muscle. Apparently the low total tissue potassium concentration is a consequence of the large EFV.Appreciable quantities of sodium (20–50 meq./l.) reside outside of the chloride space in most cases, presumably in cellular water. Furthermore, a residue of sodium remains in uterine tissue after leaching in isotonic sucrose or choline chloride. With appropriate leaching procedures, an initial rapid depletion of tissue sodium is followed by a period of relatively slow loss, indicating derivation of sodium from at least two separate tissue spaces. Equilibration in isotonic potassium chloride causes nearly complete equilibration of potassium and chloride throughout tissue water, but does not remove residual sodium, suggesting chemical binding rather than Donnan distribution as the mechanism of sodium retention.The effects of estrogen and progesterone on the concentrations of cations in uterine cells are shown to be relatively small. Estrogen causes expansion of the cellular compartment relative to the extracellular space in both rabbit and cat and decreases the concentration of cation (per liter of tissue water and per liter of intracellular fluid). Progesterone treatment, given after estrogen, interfered with the ready entrance of chloride into the cellular space of rabbit uterus exposed to isotonic choline chloride. Cat uterus was not so affected, there being very little penetration of chloride even after estrogen alone.
EFFECTS OF VARYING PROPORTIONS OF DIETARY RAPESEED OIL ON THE RAT
Authors: Beare Joyce L. , Murray T. K. , Campbell J. A.
Published: October 2017

Rapeseed oil, corn oil, and mixtures of the two oils containing 5, 10, 20, 40, and 80% rapeseed oil were fed to weanling rats at levels of 10 and 20% by weight of the purified diet. A significant decrease in body weight gains and in food consumptions occurred with the two highest levels of rapeseed oil, that is, 16 and 20% by weight of the total diet. At the same levels there was an increased lipid excretion. Corn oil and rapeseed oil which had been heated to 200 °C. for 120 hours produced no changes in weight gains when fed at the 10% level, but exhibited some growth-retarding effects at the 20% level. At both levels heated corn oil and rapeseed oil increased the liver weight of male rats.
A COMPARATIVE STUDY OF THE EFFECTS OF MALEIC HYDRAZIDE ANDp-DIMETHYLAMINOAZOBENZENE ON RAT LIVER
Authors: Mannell W. A. , Grice H. C.
Published: October 2017

Rats receiving 2% maleic hydrazide (MH) in their diet and rats fed 0.06% p-dimethylaminoazobenzene (DAB), for periods up to 26 weeks, were compared with a control group on a stock diet. For the rats on DAB there was a decrease in body weight, in desoxyribose nucleic acid (DNA) per liver cell nucleus, and in the size of the average liver cell. There was an increase in liver weight, in DNA per liver, and in the number of cells per liver. These findings confirmed previous work with this compound. No significant changes were found in any of these measurements for the rats on MH. Pathological study revealed liver neoplasms in all animals fed DAB for 10 weeks or longer. No abnormal findings were reported for any rats on MH. The results indicate that maleic hydrazide, an antisprouting agent, does not produce any effects in rat liver similar to those caused by DAB, a known carcinogen.
THE CHROMATOGRAPHIC DETERMINATION OF GLUTAMIC, ASPARTIC, AND CYSTEIC ACIDS USING AN ANION EXCHANGE RESIN
Authors: Marko A. M.
Published: October 2017

Optimum conditions for the separation of the acidic amino acids glutamic, aspartic, and cysteic on an anion exchange resin, Dowex-1 × 8, have been studied. The sample to be analyzed is adjusted to pH 7 and placed on a column of Dowex-1 × 8 previously equilibrated with 0.1 M acetate buffer at pH 4. Glutamic and aspartic acids are separated by elution with 0.1 M acetate buffer at pH 4.0–4.6. Cysteic acid is eluted with 0.2 M acetate buffer at pH 5.5–5.9. With this method quantitative separation of synthetic mixtures of the acidic amino acids has been achieved. This method has also been used to determine the dicarboxylic amino acids in acid hydrolyzates of various proteins, of normal protein-free plasma, and of normal urine.
ABNORMALITY OF ESTROGEN METABOLISM IN HUMAN SUBJECTS WITH MYOCARDIAL INFARCTION
Authors: Bauld William S. , Givner Morris L. , Milne Ian G.
Published: October 2017

Estrogen metabolism has been investigated in male subjects with and without previous myocardial infarction. The urinary excretion of estriol, estrone, and estradiol-17β has been measured 1 day before and 4 days after intramuscular injection of estradiol-17β. The excretion of the individual estrogens resulting from the administration of estradiol was determined by subtracting preinjection values from the daily excretion following injection. The resultant values of estriol (T), estrone (O), and estradiol-l7β (D) were expressed as the following ratios:[Formula: see text]These urinary estrogen ratios were found to be significantly higher in subjects with previous myocardial infarction than in control subjects. The ratios in the infarction group were not influenced by bed rest nor by the duration of time following infarction which varied from 1 week to 2 years.
THE KINETICS OF AMINO GROUP TRANSFER BY CORN RADICLE TRANSAMINASE
Authors: Cook F. S.
Published: October 2017

The kinetics of transamination are complicated by the presence of two substrates whose concentrations change appreciably during the course of the reaction. The only previously published account of the kinetics of this system deviates considerably from classical theory. Equations based on premises of Michaelis and Menten have been shown, however, to accommodate the data on reaction rate in relation to substrate concentration obtained with a corn radicle enzyme preparation by a spectrophotometric method.
AN UNEXPECTED FACTOR AFFECTING THE ALCOHOL INTAKE OF RATS
Authors: Gillespie R. J. G. , Lucas C. C.
Published: October 2017

Measurements have been made of the amount of dilute alcohol (15% v/v) consumed by adult male rats fed an adequate diet. When both water and alcohol were made available, most rats usually chose water. The relative proportions of the two liquids consumed appeared to be influenced by the positions of the food, water, and alcohol dispensers. Had these observations been less complete, the unwarranted conclusion might have been drawn that some of the rats (possibly for genetic reasons) displayed a marked preference for alcohol.
UPTAKE OF RADIOACTIVE SULPHUR BY VARIOUS TISSUES OF NORMAL AND CHOLESTEROL-FED RABBITS
Authors: Buck R. C. , Heagy F. C.
Published: October 2017

The uptake of inorganic sulphur labelled with radioactive sulphate (S35) was studied in rabbits that had been fed a normal diet and rabbits that had been fed a similar diet supplemented by the addition of 1% of cholesterol for 4 months. Paper electrophoresis of alkaline extracts of cartilage, tendon, or aorta separated a peak of radioactivity that corresponded to a band that stained metachromatically with toluidine blue and that is assumed to be chondroitin sulphate. Characteristic peaks of radioactivity were found by electrophoresis of extracts of mucin-containing tissues of the gastrointestinal tract, indicating the location of sulphated mucus with a mobility different from that of chondroitin sulphate. No radioactive material was isolated from the tissues of cholesterol-fed animals that was not present in normal tissues. Highly significant over-all differences in specific activity of sulphur were found between various tissues in both normal and cholesterol-fed rabbits. A significant elevation of both specific activity and sulphur concentration was produced in the aorta as a result of cholesterol feeding.
THE PHYSIOLOGICAL ACTIVITY OF LAMINARIN SULPHATE
Authors: Hawkins W. W. , Leonard Verna G.
Published: October 2017

When laminarin sulphate was injected intravenously into dogs it acted as an antithrombic agent. As such it was about one-third as potent as heparin. It also showed anticoagulant activity when administered subcutaneously and intramuscularly to the dog.After the intravenous administration of a moderate amount of laminarin sulphate or of heparin to the dog, considerable anticoagulant material passed into the urine. When large oral doses were given to the rat, absorption from the intestine was very small, and much of the material passed into the faeces.When it was given intravenously, laminarin sulphate acted like heparin in clearing alimentary lipaemia in the dog and the rat.
A NOTE ON THE EFFECT OF GOLD AND VITAMIN C ON THE BLOOD LEVELS OF PHENYLALANINE AND TYROSINE IN RATS
Authors: Rangneker P. V. , Dugal L. P.
Published: October 2017

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THE DETERMINATION OF THE AVAILABLE CALORIC CONTENT OF RAPESEED OIL BY RAT GROWTH
Authors: Middleton E. J. , Campbell J. A.
Published: October 2017

The available metabolic energy of rapeseed oil, semihydrogenated rapeseed oil, and corn oil was measured in terms of 7-day body-weight gains of weanling rats fed a calorically restricted diet. Standard bio-assay procedures were used with lard as a reference standard. The oils were fed at three levels equivalent to 5, 9, and 17% of the diet by weight. Growth responses to the three oils and to lard were similar and the calculated caloric content of the oils showed no significant difference from that of lard. A 1 week assay was as precise as a 5 week assay.
THE ANTILIPAEMIC ACTIVITY OF LAMINARIN SULPHATE
Authors: Mookerjea Sailen , Hawkins W. W.
Published: October 2017

When rabbits were fed a diet containing 1% cholesterol the blood serum levels of neutral fat, phospholipid, free and esterified cholesterol, and β-lipoprotein were greatly increased. After the parenteral administration of laminarin sulphate or of heparin, all these were decreased, and the electrophoretic mobility of the β-lipoprotein was increased. Laminarin sulphate showed qualitatively the same effect as heparin on the hyperlipaemia. There was no clear relationship between the magnitude of dosage of either compound and the degree of its antilipaemic effect.
EFFECTS OF CATIONS ON SUGAR ABSORPTION BY ISOLATED SURVIVING GUINEA PIG INTESTINE
Authors: Riklis E. , Quastel J. H.
Published: October 2017

The rate of absorption of glucose from isolated surviving guinea pig intestine increases with increase of the concentration of glucose in the lumen until a maximum rate is obtained. The relation between absorption rate of glucose and initial glucose concentration conforms to an equation of the Michaelis–Menten type. The apparent Km(half saturation concentration) is 7 × 10−3M. Increase of the concentration of potassium ions in the Ringer–bicarbonate solution bathing the intestine leads to an increase of the rate of glucose absorption, this being most marked with 15.6 meq./liter K+and 14 mM glucose. No such stimulating action of potassium ions is observed on glucose absorption under anaerobic conditions. The effect of increased potassium ion concentration is to accelerate the rate of transport found with low concentrations of glucose to the maximum value found with high concentrations of the sugar. Sodium ions must be present for glucose absorption to take place and omission of magnesium ions from a Ringer–bicarbonate solution, containing 15.6 meq./liter K+, brings about a decreased rate of active glucose transport. Magnesium ions are necessary for the stimulated rate of glucose absorption obtained in the presence of potassium ions. The presence of ammonium ions decreases the rate of glucose absorption. Potassium ions may be effectively replaced by rubidium ions for stimulation of glucose transport. Cesium ions do not activate. The proportion of glucose to fructose appearing in the serosal solution, when fructose is absorbed from the mucosal solution, depends on the concentration of fructose present. The proportion may be as high as 9:1 with low (7 mM) fructose concentrations; it decreases with increasing fructose concentrations. The active transport of fructose, as demonstrated by the conversion of fructose in the isolated surviving guinea pig intestine, is enhanced by the presence of potassium ions (15.6 meq./liter). The rate of transport of fructose itself is unaffected by potassium. Using radioactive glucose and fructose, it is shown that the total amount of sugar transferred through the intestine as estimated by the radioactivity appearing in the serosal solution is approximately that calculated from chemical analyses. Potassium ions have no activating action on the transport of sugars such as sorbose, mannose, and D-glucosamine, but have a marked effect on galactose transport. The results support the conclusion that potassium ions do not influence active transport of glucose, fructose, and galactose by a change of intestinal permeability to these sugars, but do so by affecting a specific phase involved in the mechanism of active transport of sugars. The presence of L-glutamine stimulates active transport of glucose, whereas that of L-glutamate tends to diminish it.
SEPARATION AND CHARACTERIZATION OF LIPOVITELLIN FROM HEN EGG YOLK
Authors: Joubert F. J. , Cook W. H.
Published: October 2017

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.
CHANGES IN SALT AND WATER DISTRIBUTION, BLOOD PRESSURE, AND ADRENAL ACTIVITY FOLLOWING NEUROHYPOPHYSEAL DENERVATION IN THE RAT
Authors: Friedman Sydney M. , Webber William A. , Scherrer Harald F. , Friedman Constance L.
Published: October 2017

Diabetes insipidus was induced by stereotaxic placement of a small lesion in the supraopticohypophyseal tract at the median eminence of the hypothalamus. The presence of diabetes insipidus was indicated by a polyuric response to an imposed salt load which, even with rigid selection criteria, occurred in a high percentage of lesion-bearing animals. In some animals the polyuric response was observed as early as the second postoperative day. No sign of remission was observed within the 4 week period of observation. Extracellular fluid volume and calculated extracellular sodium were increased in the diabetic rats. Basal blood pressure was reduced while sensitivity to norepinephrine and to pitressin was enhanced. The lesion was followed also by a reduction in gonadotrophic activity as indicated by a marked reduction in testis size.
METABOLIC CHANGES IN TRAUMA-RESISTANT RATS FOLLOWING TRAUMA
Authors: Chytil F. , Hruza Z.
Published: October 2017

Some metabolites were followed in rats which had been made resistant to trauma by exposure to Noble–Collip drum injury. In trauma-resistant rats liver glycogen levels are 50% lower than in control animals. If trauma-resistant rats are subjected to trauma that does not kill control animals then the metabolic response during the first 2 hours after trauma, determined by measuring changes in blood glucose, pyruvic acid, amino nitrogen, urea, and total acetone bodies, differs from that of control animals only by being less pronounced quantitatively. The course of metabolic changes in trauma-resistant rats differs considerably from that of control animals between the 2nd and 24th hour after trauma, especially in the levels of acetone bodies and urea in the blood. The development of the resistance to trauma is accompanied by a change in the metabolic response to trauma.
INSULIN, MAST CELL COMPONENTS, AND "ANAPHYLACTOID" INFLAMMATION
Authors: Adamkiewicz V. W. , Langlois Y. L.
Published: October 2017

The treatment of rats with an antihistaminic, or a long pretreatment with a histamine depletor, inhibits the "anaphylactoid" inflammation, and inhibits the sensitizing effect of insulin on this inflammation. However, the systemic administration of histamine, serotonin, and heparin does not restore the inhibited "anaphylactoid" inflammation, and does not restore the sensitizing effect of insulin. The three substances administered systemically are also unable to imitate, in normal rats, the sensitizing effect of insulin.
HYPERGLYCEMIC ACTION AND TOXICITY OF THE URINE OF SCHIZOPHRENIC PATIENTS
Authors: Moya F. , Dewar J. , MacIntosh M. , Hirsch S. , Townsend R.
Published: October 2017

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.
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: October 2017

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.
FURTHER OBSERVATIONS ON THE ENZYMATIC REDUCTION OF TETRAZOLIUM SALTS BY MONOAMINES
Authors: Lagnado J. R. , Sourkes T. L.
Published: October 2017

Studies on the role of purines as cofactors in the enzymatic reduction of tetrazolium salts by monoamines have led to the following results: (1) With whole rat liver extracts as the source of enzymes, several purines exhibit cofactor activity either as the free base or as the corresponding riboside and ribotide derivatives. (2) In contrast to this, mitochondrial material from rat liver is active only if adenylic acid or one of several ribotidic derivatives containing an adenylyl or similar moiety is used as cofactor. (3) Mitochondrial material utilizes hypoxanthine as cofactor for the amine/tetrazolium system only in combination with the supernatant obtained by centrifugation of tissue homogenates at 20,000 g. The additional factor present in this supernatant portion is heat-labile and nondialyzable. The possibility that this additional factor is an enzyme or enzymes converting the free base to the ribotide is discussed.Inhibition studies have revealed that the amine/tetrazolium enzyme system is sensitive to several metal-binding agents, but no direct evidence for the role of a metal in the enzymatic reaction could be obtained. It was also found that nicotinamide and adenine, neither of which exhibits cofactor activity, are potent inhibitors of the enzyme system studied.
ETHYLENE METABOLISM IN TOMATO FRUIT: II. DETERMINATION OF TOTAL AND C14-LABELLED ETHYLENE
Authors: Spencer Mary S.
Published: October 2017

A method has been developed for the determination of the radioactivity from C14-labelled ethylene absorbed in aqueous mercuric perchlorate – ethylene glycol. Counting was done on a liquid sample in a gas flow counter. This procedure was designed for the analysis of C14-labelled ethylene evolved by fruit to which possible ethylene precursors had been administered. Total ethylene could be measured manometrically on the same sample. The manometric procedure permitted analysis for ethylene in quantities evolved by one or two tomatoes or other fruit.
FURTHER STUDIES ON THE PURIFICATION OF THROMBIN
Authors: Seegers Walter H. , Levine Walter G. , Shepard Robert S.
Published: October 2017

Purified biothrombin (bovine) was fractionated with the use of amberlite IRC-50 columns to obtain resin thrombin with an activity of 4100 units/mg. dry weight or 45,000 units/mg. tyrosine. As obtained from a resin column in 0.3 M phosphate buffer, pH 8.0, the thrombin is stable for 5 days at room temperature. At 4 °C. about 70% of the activity remains after 20 weeks. The maximum molecular weight is estimated by comparing with the specific activity (2000 units/mg.) and molecular weight (62,700) of purified prothrombin as follows: 2000/4100 × 62,700 or 30,600 as the probable molecular weight. Resin thrombin can lose its fibrinogen-clotting power while esterase activity is retained. On the other hand the esterase activity can be depressed without diminishing the clotting activity. Resin thrombin lyses fibrin. When examined in an ultracentrifuge a single symmetrical peak was found with a sedimentation constant of S = 3.9 (20 °C., 0.1 M KCl, 5.5 mg./ml.) Citrate thrombin was also fractionated with the use of IRC-50 to obtain material with a specific activity of 47,000 units/mg. tyrosine.
EFFECTS OF DIFFERENT DIETARY FATS AND OF CHOLINE ON HEPATIC AND SERUM LIPIDS OF RATS
Authors: Best C. H. , Lucas C. C. , Patterson Jean M. , Ridout Jessie H.
Published: October 2017

The effects in young male rats of 10 edible oils and fats on total hepatic lipids and serum cholesterol have been compared in the presence of various amounts of dietary choline. The fats were incorporated at the 20% level in a basal hypolipotropic diet (15% protein) free from cholesterol. The diets were fed for 3 weeks. Food intake and efficiency of conversion of food to body tissue were similar with the different fats when choline was adequate; diets containing corn oil were possibly slightly less efficient. The fat-free basal ration caused heavy mortality from hemorrhagic kidney lesions. The survival rate was improved by all fats except Primex or beef fat. Coconut oil gave complete protection against renal damage.There was a negligible difference in the tendency for different fats to cause deposition of total hepatic lipids, although sunflower seed oil produced less accumulation at lower dosages of choline than did the others. The fats did differ in the extent to which they promoted deposition of cholesteryl esters.No significant differences were found in the total cholesterol of serum of rats fed the different fats. The decrease in serum cholesterol that occurs in the absence of dietary choline does not appear to be influenced by the nature of the dietary fat.
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: October 2017

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.
BIOCHEMICAL STUDIES ON SOCKEYE SALMON DURING SPAWNING MIGRATION: I. PHYSICAL MEASUREMENTS, PLASMA CHOLESTEROL, AND ELECTROLYTE LEVELS
Authors: Idler D. R. , Tsuyuki H.
Published: October 2017

Physical measurements have been made on all major organs and tissues of a pure race of migrating adult Oncorhynchus nerka. The data show that the population was sufficiently uniform in size that average weights and measurements performed on fish taken at three locations on the migration route quite accurately represented a standard fish of both sexes. The results will enable chemical analyses to be interpreted as changes in absolute amounts of a given tissue component rather than only on a percentage basis. The merits of this approach to an evaluation of changes in migrating salmon is demonstrated by the magnitude of the weight changes in many tissues during the 715-mile migration. A standard male lost only 11% of its body flesh whereas a standard female lost 30%. The alimentary tract decreased to one sixth of the initial weight. The milt increased by 51% w hile the roe increased by 272%. Thus, it is apparent that percentage composition data cannot show quantitative changes in a fish as it moves up the river. The results are discussed in relation to the findings of others on Salmonidae.Plasma cholesterol, magnesium, calcium, sulphate, and urea levels were measured on pooled blood samples from the 216 fish.
BIOCHEMICAL STUDIES ON SOCKEYE SALMON DURING SPAWNING MIGRATION: III. CHANGES IN THE PROTEIN AND NON-PROTEIN NITROGEN FRACTIONS IN MUSCLES OF MIGRATING SOCKEYE SALMON
Authors: Duncan D. W. , Tarr H. L. A.
Published: October 2017

The nitrogen content of three protein fractions and one non-protein nitrogen fraction of muscles of migrating sockeye salmon was determined at three points on the migratory route. The results have been expressed as milligrams of nitrogen per 100 g. of muscle, as per cent of the total muscle nitrogen, and as grams of nitrogen per average (standard) male or female fish.
SMOOTH MUSCLE ELECTROLYTES
Authors: Dantel Edwin E.
Published: October 2017

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.
OBSERVATIONS ON THE UPTAKE OF RADIOSULPHATE BY THE GASTRIC TISSUE AND GASTRIC SECRETION IN HISTAMINE-TREATED GUINEA PIGS
Authors: Kowalewski K. , Williams H. T. G.
Published: October 2017

The effect of histamine on the uptake of radiosulphate by gastric tissue and gastric juice in guinea pigs was investigated. Radioactivity was recorded 4 hours after the administration of S35-labelled sulphate to normal controls and to histamine-treated animals.The radioactivity of fractions considered to contain sulphated mucopolysaccharides was also investigated.The uptake of radiosulphate by gastric tissue and juice was significantly higher in histamine-treated animals than in control guinea pigs.The S35 uptake by gastric sulphomucopolysaccharides was considered to represent the concentration of isotope by mucous cells and its secretion. This selective uptake was also markedly effected by histamine.Histamine may be a stimulant of the gastric mucous cells under the experimental conditions described.
PLANT STEROLS, DEGREE OF UNSATURATION, AND HYPOCHOLESTEROLEMIC ACTION OF CERTAIN FATS
Authors: Beveridge J. M. R. , Connell W. Ford , Mayer G. A. , Haust H. L.
Published: October 2017

Dietary experiments in which food was supplied in the form of a homogeneous liquid formula ration of definitely known composition have been performed on 171 subjects (159 men and 12 women, university students).During an initial period of 8 days all subjects ate the same ration and then groups of 8 to 12 individuals were given rations varying in respect of the fat moiety for a further 8 days. Plasma cholesterol analyses were performed at day 0, 4, 8, 12, and 16.The results obtained were interpreted as indicating that: firstly, there is no simple relationship between the hypocholesterolemic effect of an oil and degree of unsaturation; secondly, sitosterol or something closely associated with this sterol in the unsaponifiable matter accounts for a large part of the hypocholesterolemic activity of corn oil; and thirdly, certain fatty acids of short chain length or some other substance in butterfat and coconut oil have a hypercholesterolemic effect.
MECHANISM OF ACTION OF THE LACTIC DEHYDROGENASE OF THE MAMMALIAN ERYTHROCYTE: I. INFLUENCE OF INHIBITORS
Authors: Ottolenghi Paul , Denstedt Orville F.
Published: October 2017

This paper pertains to the inhibition of lactic dehydrogenase by substances structurally related to its substrates, pyruvate and lactate. Oxalate, tartronate, and malonate inhibit the enzyme in a competitive manner towards lactate, and in a noncompetitive manner towards pyruvate. Phenoxyacetate causes simultaneous competitive and noncompetitive inhibition towards both lactate and pyruvate. The results obtained lead to the conclusion that, for their activation, pyruvate and lactate react with different sites on the enzyme surface.
THE SIGNIFICANCE OF THE NUMBER OF PRECIPITIN BANDS IN AGAR GEL MEDIUM FOR THE DETERMINATION OF THE COMPLEXITY OF ANTIGENS
Authors: Richter M. , Rose B. , Sehon A. H.
Published: October 2017

A new interpretation is presented to account for inconsistancies which may arise when comparing data obtained with antibody–antigen systems in agar and in liquid media. For a model system, different haptens (p-aminobenzoic acid and p-sulphanilic acid) coupled to proteins were used. It has been demonstrated that the number of precipitin bands formed in agar medium by these antibody–antigen systems may be smaller than the number of optimal proportion zones detected for these systems in liquid medium, provided the different haptens are coupled to the same carrier. This effect is not due to a lesser sensitivity of the reaction in agar but rather to the inherent limitations of this method. Thus, by the agar technique, not more than one antigenic moiety (present on a molecule) is detected, whereas by the precipitin test in liquid medium optimal proportion zones with respect to each of the antigenic moieties (on the molecule) may be detected. This limitation in agar is not considered to detract from the value of the agar gel technique when it is used for the detection of independent antigens.
THE EFFECT OF PYRIDOXINE DEFICIENCY ON BLOOD UREA IN MICE
Authors: Lyon Jr. John B. , Arnold Eugene A. , Farmer Rita
Published: October 2017

Blood urea levels were determined in weanling, young, and adult C57and I strain mice fed vitamin B6-deficient or complete rations. Elevations in blood urea were found in some of the deprived groups, but they were transient, and the maxima occurred early in the deficiency, at 2 weeks. Although the I strain is more susceptible to a B6deficiency, strain differences were found in only one age group. Increases in blood urea were also induced by simple environmental changes. It was concluded that elevations in blood urea are not directly related to a pyridoxine deficiency in these inbred strains of mice.
PREPARATION OF AN ESTRONE–PROTEIN CONJUGATE
Authors: Goodfriend L. , Sehon A. H.
Published: October 2017

A procedure is described for the preparation of an estrone–protein conjugate. The 17-amino derivative of estrone was prepared and converted by phosgenation to estrone-17-isocyanate. The latter was coupled to rabbit serum albumin. Ultraviolet analysis and determination of free amino groups of both albumin and estrone–albumin conjugate showed that the latter contained about 25 estrone residues per albumin molecule. Electrophoretic analysis provided additional evidence that coupling had occurred at the ε-amino groups of the lysine residues of albumin.
ANTAGONISTS TO SCHRADAN POISONING IN MICE
Authors: O'Brien R. D. , Davison A. N.
Published: October 2017

Twelve agents have been tested for their capacity to antagonize schradan poisoning. Three showed promise, and were examined in more detail. The best compound, SKF525A, confers protection even if given after the schradan. When given simultaneously, 20 mg/kg of SKF525A raises the LD50of schradan from 21 to about 80 mg/kg. There are two optima in the treatment times with SKF525A: at 1 hour before and simultaneously with the schradan. SKF525A also has a protective action against other compounds, notably Guthion, yet is without effect on parathion poisoning. The order of effectiveness of SKF525A, iproniazid, and 3-acetylpyridine in antagonizing schradan poisoning closely parallels their order of effectiveness in antagonizing pentobarbital detoxification; the significance of this is discussed. The protection afforded by these agents is probably due to inhibition of the activation of phosphorothionates and phosphoroamidates.
EFFECT OF AMBIENT TEMPERATURE ON THERMAL RESPONSES TO DRUGS
Authors: Shemano Irving , Nickerson Mark
Published: October 2017

Thermal responses to a variety of drugs have been investigated at various ambient temperatures, using unanesthetized rats, either lightly restrained or paralyzed with tubocurarine. The results indicate that ambient temperature is a major factor determining thermal responses to many drugs. Experiments on lightly restrained rats demonstrated that the critical ambient temperature, the temperature above which hyperthermia is evoked and below which hypothermia is produced, is about 30 °C (in the thermoneutral range) for Hydergine, ergotamine, LSD-25, and serotonin. The critical ambient temperature for chlorpromazine is approximately 36 °C, and that for 2,4-dinitrophenol, 20 °C. Reserpine produced a consistent hypothermia at 23 °C, but somewhat inconsistent effects at ambient temperatures above this up to 39 °C. Complete curarization abolished the hypothermic effects of all the above agents except chlorpromazine. The production of both hyperthermia and hypothermia by most of the drugs studied suggests that they influence temperature-regulating centers of the central nervous system.
THE ANTHOCYANINS OF SOME CANADIAN PLANTS
Authors: Acheson R. M.
Published: October 2017

The anthocyanins of a number of Canadian flowers and berries have been examined and the anthocyanidins identified. No new types were detected.
ETHYLENE METABOLISM IN TOMATO FRUIT: III. EFFECT OF 2,4-DINITROPHENOL ON RESPIRATION, ETHYLENE EVOLUTION, AND RIPENING
Authors: Spencer Mary S.
Published: October 2017

The role of phosphorylation in fruit ripening was investigated by the introduction of a phosphorylation uncoupling agent, 2,4-dinitrophenol (DNP), into intact fruit. DNP produced a large increase in carbon dioxide evolution by mature green tomatoes, but not by tomatoes in earlier or later stages of maturity. In contrast to its effect on carbon dioxide production, DNP treatment of mature green tomatoes resulted in an immediate depression of ethylene evolution and in failure of the fruit to ripen normally. This suggests a requirement for oxidative phosphorylation for fruit ripening and ethylene production. It was also observed that cell walls of mature green tomatoes treated with the uncoupling agent became wavy and greatly thickened.
STUDIES ON THE PRESERVATION OF BLOOD: VII. THE INFLUENCE OF INOSINE ON THE METABOLIC BEHAVIOR OF THE ERYTHROCYTE DURING THE PRESERVATION OF BLOOD IN THE COLD
Authors: Rubinstein D. , Kashket S. , Blostein Rhoda , Denstedt O. F.
Published: October 2017

Inosine, like other purine nucleosides when added to preserved blood specimens, induces a resynthesis of organic phosphate esters in the erythrocytes. Apart from the difference in rates of reaction, the metabolic reconstitution of the cells is the same at 37° and 4 °C. The reconstitution of the esters occurs rapidly even at 4 °C, and the higher the concentration of inosine added, the more prolonged is the maintenance of the esters. When inosine was added repeatedly to blood samples during storage, a phase of synthesis was induced with each addition of nucleoside. The capacity of the erythrocytes to resynthesize 2,3-diphosphoglyceric acid (DPG) remained normal regardless of the storage age of the sample but the capacity to replenish ATP decreased with the duration of storage. Addition of inosine at the end of the third week of cold storage can effect a high degree of restoration of metabolic viability in the cells at 4 °C within 24 hours.
THE EFFECT OF VAGOTOMY AND DENERVATION OF THE CAROTID SINUS ON DIURESIS FOLLOWING PLASMA VOLUME EXPANSION
Authors: Pearce J. W.
Published: October 2017

The hypothesis exists that afferent vagal fibers, arising in cardiac atrial stretch receptors, serve as the sensory limb of a reflex mechanism sensitive to variations in blood volume and producing corresponding changes in urine flow. Section of the vagi did not, however, prevent the diuretic and chloruretic response to expansion of the plasma volume with isotonic infusions. Carotid sinus denervation alone or combined with vagotomy also failed to prevent the diuresis and chloruresis following infusion in most experiments, although in a few cases the response was absent or diminished after the combined procedure. Reasons are given for believing that the bovine albumin infusion used did not act directly on the kidney to increase urine output, but rather through a reflex mechanism which could not have depended on the integrity of the vagi. It is concluded that receptors additional to those in the cardiac atria and the carotid sinus must contribute to the sensory component of a reflex mechanism regulating plasma volume.
THE ELECTROPHORETIC ANALYSIS OF PLANT VIRUS PREPARATIONS
Authors: Townsley P. M.
Published: October 2017

Zone electrophoresis in agar gel has been used for separating tobacco mosaic virus and potato virus X from crude plant extracts and reaction mixtures. The viruses were located within the gel by autoradiographic, serological, and protein-staining methods.
THE PREPARATION OF SUCROSE-C14WITH HIGH SPECIFIC ACTIVITY AND HIGH TRACER YIELD USING DETACHED SUGAR BEET LEAVES
Authors: Nelson C. D. , Mortimer D. C.
Published: October 2017

Radioactive sucrose, in millicurie amounts, was prepared by feeding a detached sugar beet leaf C14O2in air for 15 to 20 minutes followed by 5 to 20 minutes additional photosynthesis in air. The low endogenous sucrose in the leaf coupled with the improved tracer yield effected by the displacement technique gave sucrose with high specific activity. This sucrose-C14, hydrolyzed by 1% invertase, was a good source for radioactive glucose and fructose. Paper chromatographic procedures were used for the isolation and purification of the sugars.
THE DETERMINATION OF CALCIUM AND MAGNESIUM IN BLOOD USING ONE INDICATOR
Authors: Robinson H. M. Czajkowska , Rathbun J. C.
Published: October 2017

A rapid ethylenediaminetetraacetic acid titration for calcium and magnesium in serum requiring 0.1 ml of blood is described. Eriochrome black T is used as the sole indicator and the end point is observed photometrically. After determination of total calcium and magnesium, the calcium is removed as oxalate, the magnesium determined separately, and the calcium obtained by difference. The method is highly reproducible and is sensitive to ± 0.1 mg% of either calcium or magnesium.
ACETYLCHOLINE IN PERIPLANETA AMERICANA L.: III. ACETYLCHOLINE IN ROACHES TREATED WITH TETRAETHYL PYROPHOSPHATE AND 2,2-BIS(p-CHLOROPHENYL)-1,1,1-TRICHLOROETHANE
Authors: Colhoun E. H.
Published: October 2017

The levels of acetylcholine (ACh) in the thoracic nerve cords of cockroaches were increased by the topical application of 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane (DDT) and of tetraethyl pyrophosphate (TEPP), but only TEPP inhibited cholinesterase (ChE). Improvements in the correlation of symptoms, nervous activity, and ACh levels with ChE were obtained when nerve cords were homogenized in saline containing ACh, which prevented further inhibition of ChE by TEPP found to be present in blood and nervous tissue. There was a similarity in the distribution of ACh in thoracic nerve cords of roaches after topical treatment with TEPP and DDT but the physiological properties of the blood revealed differences in the mode of action of the two insecticides. The effects of blood from the poisoned insects on the electrical activity of the isolated nerve cord of roaches are discussed in relation to the penetration of the nerve cord by known neurohumors.
ACTIVATION OF ACTH RELEASE BY NEUROHYPOPHYSIAL PEPTIDES
Authors: Saffran Murray
Published: October 2017

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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: October 2017

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.
SEPARATION OF THE VALYL-LEUCYL- AND VALYL-GLUTAMYL-POLYPEPTIDE CHAINS OF HORSE GLOBIN BY FRACTIONAL PRECIPITATION AND COLUMN CHROMATOGRAPHY
Authors: Wilson Strathearn , Smith David B.
Published: October 2017

Horse globin has been fractionated into two components by stepwise addition of acid acetone to an acidified globin solution and by gradient elution with urea from a carboxylic-type ion exchange resin at low pH.The components obtained by both methods are similar to those prepared earlier by electrophoresis. They have similar molecular weights (about 16,000) and appear to be present in nearly equal amounts. One has the N-terminal sequence valyl-leucyl- and the other valyl-glutamyl-. They differ electrokinetically and in other properties.