bluuebunny/crossref_metadata_2025 huggingface dataset:
PREPARATION OF CAFFEIC AND DIHYDROCAFFEIC ACIDS BY METHODS SUITABLE FOR INTRODUCTION OF C14 INTO THE β-POSITION
Authors: Neish A. C.
Published: December 2009

3,4-(Dibenzyloxy)-benzoyl chloride (m.p. 95°) was prepared from the corresponding acid, and reduced to 3,4-(dibenzyloxy)-benzaldehyde (m.p. 86°) by Rosenmund's method. The over-all yield of this aldehyde was 52%, based on the barium carbonate used for preparation of the acid. The aldehyde was debenzylated by hydrogen bromide in acetic acid, and the protocatechualdehyde thus obtained was condensed with malonic acid, to give caffeic acid. Condensation of 3,4-(dibenzyloxy)-benzaldehyde with malonic acid gave 3,4–(dibenzyloxy)-cinnamic acid (m.p. 206–208°) which was converted to dihydrocaffeic acid by catalytic hydrogenation. The over-all yields of caffeic and dihydrocaffeic acids were 36% and 39%, respectively, based on barium carbonate. Protocatechuic acid was readily obtained by hydrogenolysis of 3,4-(dibenzyloxy)-benzoic acid; the yield was 70% based on carbonate.
LOSS OF PHOSPHOLIPID IN THE SKIN OF TUMOR-BEARING RATS
Authors: Boyd Eldon M. , Millar Irene E.
Published: December 2009

There occurs a unique, statistically significant fall in the level of phospholipid in the skin of albino rats bearing large Walker carcinosarcomata 256. The shift is similar to that produced by application of methylcholanthrene. It is preceded by loss of skin weight and increases in levels of skin water, cholesterol, and cholestrol esters. It is accompanied by loss of skin neutral fat and cholesterol esters. The quadratic shift in cholesterol esters occurs in hair before it occurs in skin, and is accompanied by a loss of hair weight and a slight but significant rise in levels of hair neutral fat. Declining levels of skin phospholipid may be part of the mechanism of production of the sallow appearance of the skin in late malignancy.
ZONE ELECTROPHORESIS OF THE PROTEINS OF THE FOWL'S SERUM AND EGG YOLK
Authors: McCully K. A. , Maw W. A. , Common R. H.
Published: December 2009

In addition to the six protein fractions distinguishable in sera from cocks or sexually immature pullets by zone electrophoresis in aqueous veronal, two lipoprotein zones have now been distinguished in sera from laying hens or estrogenized pullets by this same technique. Phosvitin has been detected in serum of estrogenized hens by zone electrophoresis of a saline solution of crude serum lipovitellin obtained from the serum. Six protein zones have been distinguished in similar electropherograms of egg yolk. The six protein zones have been identified provisionally, and in order of decreasing mobility under the conditions used, as phosvitin, α-livetin, β-livetin, γ-livetin, lipoprotein P-1 (possibly a lipovitellenin complex), and lipoprotein P-2 (possibly a lipovitellin complex). Evidence is submitted that the foregoing two major lipoprotein zones from egg yolk are closely similar to, or identical with, the two lipoprotein zones from sera of laying hens or estrogenized pullets. The status of a seventh minor protein zone in electropherograms of yolk protein is uncertain.
ISOMERIZATION OF VITAMIN A IN VIVO
Authors: Murray T. K. , Stainer D. W. , Campbell J. A.
Published: December 2009

Pure all-trans and neovitamin A alcohol were administered orally to young, vitamin-A-deficient rats and the vitamin A and proportion of neovitamin A in the intestinal tract, liver and kidney were measured. In both cases considerable isomerization occurred in the stomach and the resulting mixture of isomers appeared to be absorbed by the intestine. The dose of all-trans vitamin A was taken up by the intestine more quickly than was the neovitamin A dose. An oral or subcutaneous dose of neovitamin A resulted in a relatively high proportion of neovitamin A in the liver but this proportion decreased during depletion to that found after a dose of all-trans vitamin A. The proportion of neovitamin A varied inversely with the size of dose of all-trans vitamin A and directly with the size of dose of neovitamin A. The significance of these results is discussed.
THE INHIBITION OF OXIDATIVE AND PHOSPHORYLATIVE ENZYMES IN RAT LIVER MITOCHONDRIA BY AMINOAZOBENZENE DERIVATIVES
Authors: McMurray W. C.
Published: December 2009

The liver carcinogen, dimethylaminoazobenzene, inhibited in vitro the oxidation of a variety of pyridine nucleotide linked substrates of rat liver mitochondria without affecting the process of oxidative phosphorylation. Cytochrome c oxidase activity was not inhibited by the carcinogen, nor was the succinoxidase activity, but the phosphorylation accompanying succinate oxidation was uncoupled. Similar effects were noted with other aminoazobenzene derivatives, but did not appear to be correlated with the ability of the compounds to evoke tumors.The site of the respiratory inhibition by dimethylaminoazobenzene appears to be at the level between reduced pyridine nucleotide and cytochrome c in the respiratory chain. Mitochondrial dehydrogenase activity was not inhibited, while the oxidation of reduced diphosphopyridine nucleotide was markedly decreased. The reduction of the electron acceptor, ferricyanide, by pyridine nucleotide linked substrates was also strongly inhibited but the reduction of tetrazolium compounds was not affected. The latter observations suggest that dimethylaminoazobenzene produces a metabolic block between reduced flavin and cytochrome c in the mitochondrial electron transport system.
THE EFFECT OF DIETARY MARINE FISH OILS ON THE SERUM CHOLESTEROL LEVELS IN HYPERCHOLESTEROLEMIC CHICKENS
Authors: Wood J. D. , Biely Jacob
Published: December 2009

An investigation was carried out into the effect of marine fish oils on the serum cholesterol levels in hypercholesterolemic chickens. The oils were fed at the 10% level in the diet. Lingcod liver oil and halibut liver oil prevented the hypercholesterolemic effect of supplementary cholesterol, whereas crude herring oil increased the hypercholesterolemia to the same extent as did corn oil and tallow. Ratfish liver oil, dogfish liver oil, and basking shark liver oil had less noticeable effects on the cholesterol levels. No clear explanation could be given for the observed behavior but there seemed to be a difference in the effects on serum cholesterol of liver oils from teleostei fish and from selachii fish, the former class of liver oils being much more potent in preventing the increase in serum cholesterol concentration in chickens caused by the addition of cholesterol to the diet.
STUDIES ON WHEAT PLANTS USING CARBON-14 COMPOUNDS: XI THE RELATIVE INCORPORATION OF CARBONS 1, 2, AND 3 OF PYRUVATE
Authors: McConnell W. B. , Nath R. , Spencer J. F. T.
Published: December 2009

The incorporation of carbons 1, 2, and 3 of pyruvate into maturing plants has been compared by use of pyruvate-1-C14, -2-C14, and -3-C14as tracers. The carbon-14 content of kernel proteins and lipids increased markedly when pyruvate was labelled in higher-number positions. The effect was strikingly demonstrated in the glutamic acid from the protein in which the specific activity varied in the proportion 1:5:10.5 when pyruvate labelled in the 1, 2, or 3 position respectively was administered. A small amount of administered pyruvate appeared to be utilized as the intact carbon skeleton for biosynthesis of starch and of alanine. It is considered, however, that most of the injected pyruvate undergoes decarboxylation, carbon-1 being utilized as carbon dioxide and carbons 2 and 3 as acetate.
AN ANOMALOUS TRICARBOXYLIC ACID CYCLE IN ACETOBACTER MELANOGENUM
Authors: Bone D. H. , Hochster R. M.
Published: December 2009

Extracts of gluconate-grown Acetobacter melanogenum contain condensing enzyme and DPN-isocitric dehydrogenase of low specific activity. No evidence could be found for the presence of phosphotransacetylase, aconitase, or TPN-isocitric dehydrogenase. Since the organism or its extracts cannot synthesize the necessary four carbon compounds from pyruvate and from acetate, it is concluded that the tricarboxylic acid cycle does not function in extracts of this organism in the usually accepted manner.The pyruvic oxidase system was found to be highly active, acetaldehyde being the chief intermediate and acetate the end product. The mechanism for the slow incorporation of acetate into other cell constituents is, at present, unknown.
CONDUCTION BLOCK OF TERMINAL SOMATIC MOTOR FIBERS IN TICK PARALYSIS
Authors: Murnaghan Maurice F.
Published: December 2009

In the perfused anterior tibial muscle of the tick-paralyzed dog acetylcholine in excess of the control value is not liberated on stimulation of the peroneal nerve; in the normal muscle 7 μμg of acetylcholine is liberated per nerve volley. The paralysis is evidently not due to defective synthesis of acetylcholine because acetylcholine is liberated in control and high-potassium perfusates, the choline acetylase activity and the acetylcholine content of lumbar ventral roots and peroneal nerves do not differ from that in normal dogs, and the tick-paralyzed muscle differs from that in the hemicholinium-treated animal in its response to a train of nerve pulses after previous tetanization. As somatic motor nerve fibers in the paralyzed dog have previously been shown to conduct a nerve impulse and the factors required for acetylcholine release at the nerve terminal apparently are not absent in the paralyzed animal, the mechanism of the paralysis is probably due to an inability of the nerve impulse to traverse the terminal presynaptic fibers. The 'lesion' evidently extends to the end of the presynaptic fiber, i.e. more distally than in botulism, because direct stimulation of the tick-paralyzed muscle fails to liberate acetylcholine.
RADIATION, THE CELLULAR APPROACH
Authors: Clark Gordon M. , Baker Donald G.
Published: December 2009

The basic biological action of radiation must initially involve particular cells. The sensitivity of various cells differs but some of the differences may be due to a dose-rate effect. When cells are irradiated with doses in the lethal range, inhibition of cell division occurs. A notable feature of mitotic inhibition is that it depends not only on dose but on dose rate. Chromosome breaks produced in cells may be a visible manifestation of an interruption in chemical synthesis produced by the passage of ionizing particles. The effect of oxygen is apparently of primary importance in biological changes produced by irradiation. Almost all are decreased in its absence. The current trend in research on the cellular level is towards determining the more obscure injuries which cannot be seen under the microscope.
THE ACTION OF PANCREATIC DEOXYRIBONUCLEASE ON OLIGONUCLEOTIDES FROM CALF THYMUS DEOXYRIBONUCLEIC ACID
Authors: Hurst R. O. , Findlay Dorothy
Published: December 2009

Hydrolysis of sodium oligonucleotide by crystalline pancreatic deoxyribonuclease (DNA-ase) has been studied in the presence of different metal ions and the chelating agent ethylenediaminetetraacetate (EDTA). Although EDTA inhibited the action of DNA-ase when magnesium or cobaltous ions were used as activator, the enzyme activity was enhanced in the presence of manganous ions and EDTA. The results are interpreted as indicating the presence of an oligonucleotidase function in the enzyme preparation. A differential assay method for DNA-ase and oligonucleotidase activity has been devised and the evidence obtained gives additional support for this conclusion.
SOME BIOLOGICAL PROBLEMS IN CANCER BIOCHEMISTRY
Authors: Siminovitch Louis , Axelrad Arthur
Published: December 2009

Understanding of the cancer process in chemical terms has been seriously hampered by the difficulty of interpreting results of biochemical comparisons between masses of tumor and of normal tissue. Normal tissue consists of a variety of cell types and tumors may originate from one or more of these. As whole masses, therefore, normal tissues cannot serve as adequate controls for experiments on any single tumor. Tumor cell populations, even those arising from a single cell type, are themselves cytogenetically and continually undergoing changes during growth (progression). It is thus difficult, if not impossible, to separate the relevant from the irrelevant biochemical features of malignancy.Progress in this field requires means of dealing with the problem of biological heterogeneity. Several biochemical approaches that are free from the hazards of heterogeneity and which have already yielded valuable results, or appear promising, are indicated. These include: (1) The use of ascites tumors for studying the biochemical machinery of cells. No normal tissue exists, however, that could serve as satisfactory control. (2) Biochemical comparisons between pairs of tumor lines which differ by only one inherited characteristic of malignancy. These might reveal a biochemical basis for the biological properties of tumor cells with different degrees of malignancy. (3) Elucidation of normal growth-controlling mechanisms between cells, e.g. action of hormones at the cellular level, and within cells, e.g. mechanism of feed-back control of enzymes and metabolic pathways. (4) Further research into the biochemistry of plant tumor induction in vitro. Here biochemical changes associated with inherited changes leading to nutritional autonomy and uncontrolled growth have already been demonstrated. (5) Studies on the biochemical events during induction of malignancy by viruses in clonal cultures of animal cells in vitro. These could serve as useful models of the whole process of carcinogenesis.
CHANGES IN THROMBIN GENERATION AND ANTITHROMBIN TITER FOLLOWING MASSIVE BLEEDING AND TRANSFUSION IN DOGS
Authors: Monkhouse F. C. , Milojevic Susan
Published: December 2009

Thrombin generation, plasma antithrombin levels, and plasma protein levels were measured in dogs following rapid massive bleeding and transfusion. Three groups of four dogs per group were used. One group was transfused with saline, one with dextran, and one with a plasma fraction. The plasma fraction was prepared from mixed dog plasma by a procedure designed to remove most of the known clotting factors with a minimum of damage to other proteins. The in vivo dilution of blood by transfusion with two volumes of saline or one of plasma fraction increased the rate of thrombin generation. Dilution by transfusion with dextran decreased both rate and amount of thrombin generation. For the first few hours following transfusion with saline, plasma antithrombin increased more rapidly than total plasma protein. This was probably a result of increased lymph flow. Fluctuations in the coagulability of the blood were observed up to 72 hours following bleeding and transfusion. The fluctuations following saline transfusion were less prolonged than when dextran or plasma fraction was used.
THE OXIDATION OF SUCCINATE IN EXTRACTS OF XANTHOMONAS PHASEOLI
Authors: Madsen N. B.
Published: December 2009

Succinoxidase and succinic dehydrogenase were found in cell-free extracts of Xanthomonas phaseoli, obtained by sonic oscillation, and remained largely in the supernatant solution after ultracentrifugation. The effect of time of exposure of the cells to sonic oscillation on cell breakage was found to follow first order reaction kinetics, as was the "solubilization" of succinic dehydrogenase and succinoxidase. It appears that the two enzymatic activities are released from the cell in a particulate form which is further fragmented on continued treatment in the sonic oscillator.The clear supernatant solution obtained after ultracentrifugation of the cell-free extract was found to contain those members of the electron transport chain which had previously been found in the intact cell, namely, flavoprotein and cytochromes b1, a1, and a2. These substances could be reduced by the addition of succinate. Malonate prevented this reduction. The effects of various inhibitors on the succinoxidase system and on succinic dehydrogenase are presented and discussed in relation to the operation of the electron transport chain in the oxidation of succinate by this organism.
STUDIES ON THE IN VITRO ANTITUMOR ACTIVITY OF FATTY ACIDS: II. SATURATED DICARBOXYLIC ACIDS
Authors: Morgan Joseph F. , Tolnai Susan , Townsend Gordon F.
Published: December 2009

Previous studies, which showed that 10-hydroxy-2-decenoic acid from royal jelly possessed in vitro antitumor activity, have been extended to saturated dicarboxylic fatty acids. Seven of eight compounds tested in a series of chain length from C3 to C10 completely prevented the development of the ascites forms of the 6C3HED lymphosarcoma, the Ehrlich carcinoma, and the TA3 mammary carcinoma, as well as the transplantable leukemia of AKR mice. This in vitro antitumor activity could be demonstrated only at pH values below 5.0 and required admixture of the tumor cells and test compounds prior to inoculation of the mice. In general, the antitumor activity of the saturated dicarboxylic acids was found to increase progressively with increasing length of the fatty acid chain.
LINGCOD MUSCLE PHOSPHOMONOESTERASES: I. ACID PHOSPHATASES THAT HYDROLYZEp-NITROPHENYL PHOSPHATE
Authors: Tomlinson Neil , Warren R. A. J.
Published: December 2009

Five fractions (A to E), each possessing acid phosphomonoesterase activity, were separated from an aqueous extract of the muscle of lingcod (Ophiodon elongatus) by stepwise chromatography on diethylaminoethyl cellulose in the free-base form.Fraction A required Zn++or Mn++for activity, was inhibited by heparin, and had its pH optimum at 6.0. Fraction E required Zn++for activity, was not inhibited by heparin, and had its pH optimum at 5.5. Fractions B, C, and D did not require metal ions for activity, and were distinguished from each other by differences in response to pH, cysteine, ethylenediaminetetraacetate, fluoride, and tartrate.The pH range over which fraction A was active was shifted to slightly higher values when Mn++was the activator rather than Zn++. Also, A was inhibited strongly by cysteine when activated by Zn++, but not when activated by Mn++. Data are presented that indicate these differences were due to different properties of the activating ions, rather than to the presence in fraction A of two enzymes, one activated by Zn++and the other by Mn++.
FATTY ACID, CHOLESTEROL, AND ACETOACETATE BIOSYNTHESIS IN LIVER HOMOGENATES FROM NORMAL AND STARVED GUINEA PIGS
Authors: Sauer Frank
Published: December 2009

Fatty acid, cholesterol, and acetoacetate biosynthesis was studied with liver homogenates from normal and starved guinea pigs. Starvation suppressed the incorporation of acetate into fatty acids and cholesterol but not into acetoacetate. The in vitro biosynthesis of cholesterol and fatty acids was not restored by the addition of either G-6-P or isocitrate in combination with TPN, nor was it restored by orally dosing the starved animals with dextrose. The addition of isocitrate to normal homogenates depressed cholesterogenesis and stimulated lipogenesis.
EFFECTS OF DIET ON INCORPORATION OF ACETATE-1-C14INTO CHOLESTEROL BY RAT LIVER SLICES
Authors: Carroll K. K.
Published: December 2009

The rate of incorporation of acetate-1-C14into cholesterol by rat liver slices decreased when animals were transferred from a commercial chow diet to semisynthetic diets. A greater decrease was observed when the test diet contained oleic acid or olive oil than when it contained higher homologues of oleic acid, or preparations of cerebrosides. The decrease was not affected by the presence or absence of fat-soluble vitamins in the test diet containing oleic acid. Amphenone B affected acetate incorporation into liver cholesterol differently depending on whether it was fed in a chow diet or a semisynthetic diet. The incorporation of acetate into liver fatty acids of rats fed various diets usually increased or decreased with incorporation into cholesterol but differences between groups were less marked. Incorporation of acetate into cholesterol by intestinal mucosa was relatively insensitive to changes in diet.
METABOLIC EFFECTS OF UREA ADMINISTRATION ON ACUTE HYPOTHERMIA IN RATS
Authors: Beaton John R.
Published: December 2009

Acute hypothermia (15 °C rectal temperature) has been induced in fasted rats with and without prior intraperitoneal administration of urea. In the hypothermic animal, not given urea, blood glucose and pH were significantly decreased; blood lactic acid, inorganic phosphorus, and packed cell volume were significantly increased; no alterations occurred in blood levels of pyruvic acid, total acid-soluble phosphorus, urea, nor amino nitrogen. Prior administration of urea prevented significant alterations of blood glucose and lactic acid in the cooled animal. In the non-cooled animal, urea treatment resulted in elevated blood glucose levels. These effects are discussed in relation to the beneficial action of urea in permitting successful resuscitation and survival in a normal condition of rats cooled to rectal temperatures of 0–3 °C.
DEGRADATION BY HYDRAZINE OF BOVINE PLASMA ALBUMIN AND LYSOZYME
Authors: Champagne Madeleine , Smith David B.
Published: December 2009

The effect of hydrazine and hydrazine hydrate on bovine plasma albumin and lysozyme at 5° and 20 °C has been studied by viscosity, sedimentation, and molecular weight measurements. The appearance of new N-terminal amino acids and peptides has been demonstrated. The effect of these reagents is an initial unfolding of the molecule followed by slow, non-random fission to smaller particles.
THE METABOLISM OF ALDOSTERONE BY SURVIVING DOG AND HUMAN LIVER SLICES
Authors: Sandor Thomas , Nowaczynski Wojciech J. , Genest Jacques
Published: December 2009

Surviving dog liver slices were incubated with d,l-aldosterone-21-monoacetate, d,l-aldosterone, d-aldosterone, and d-aldosterone-21-C14. Human liver slices were incubated with d,l-aldosterone-21-monoacetate and d-aldosterone. The incubations were performed in a Krebs–Ringer–phosphate medium (pH 7.4), with 200 mg glucose added per 100 ml of medium, at a temperature of 37 °C. After incubation, the medium was extracted with chloroform and the crude extract extensively fractionated on column and paper chromatographic systems. In addition to free aldosterone, four metabolic products were isolated, two ring A reduced α-ketolic and two ultraviolet absorbing, non-reducing substances. The partial chemical characterization of these metabolites was attempted. The search for aldosterone metabolites in human urine resulted in the isolation of a substance in acetate form from the urine of a patient suffering from primary aldosteronism which may be identical with one of the ring A reduced metabolites obtained in the in vitro experiments.
EFFECT OF LIPOTROPIC AGENTS UPON THE NET SYNTHESIS OF CHOLESTEROL IN THE RAT
Authors: Mookerjea Sailen , Lucas C. C.
Published: December 2009

The content of cholesterol in the bodies of young male rats fed a basal hypolipotropic diet has been compared with that of other rats pair-fed on similar diets supplemented with choline chloride, methionine, or vitamin B12, respectively. Increased efficiency of utilization of the food and variable lipotropic effects were observed, but no significant difference was found in the total amounts of cholesterol at the end of the 3-week test periods. The lipotropic agents do not influence to any significant degree the net biosynthesis of cholesterol in rats fed this type of diet but they do affect the distribution, tending to keep the liver lipids, including cholesterol, in the normal range.
STUDIES ON WHEAT PLANTS USING CARBON-14 COMPOUNDS: XIII. INCORPORATION OF α-AMINO ADIPIC ACID-6-C14IN WHEAT PLANTS
Authors: Nath R. , McConnell W. B.
Published: December 2009

α-Amino adipic acid-6-C14was injected into the stems of wheat plants and the distribution of carbon-14 in the mature plants was studied. About 80% of carbon-14 injected was recovered in the plants, the kernels alone accounting for 56%.Glutamic acid, labelled predominantly in carbon-5, was the most radioactive compound isolated from wheat kernels, a result in accord with the concept that acetate-1-C14was a product of α-amino adipic acid-6-C14metabolism in the wheat plant.The specific activity of the lysine of the protein was low and hence the data provide no evidence that α-amino adipic acid is a precursor of lysine in wheat.
THE DISTRIBUTION OF RADIOACTIVE PHOSPHORUS IN THE BLOOD AND TISSUES OF RABBITS TREATED WITH TAGGED ISOPROPYL METHYLPHOSPHONOFLUORIDATE (SARIN)
Authors: McPhail M. K. , Adie P. A.
Published: December 2009

By using sarin (isopropyl methylphosphonofluoridate) tagged with P32 it has been possible to determine the distribution of the P32 in the tissues after injection of sarin solutions or after cutaneous application of sarin vapor. In rabbits the percentage of P32 per gram of tissue after injection of sarin P32 was found to be higher in lung and kidneys than in other organs. The ratio of the P32 in blood to that in the body as a whole was found to decrease with the time after injection. The ratio also varied with the time after cutaneous application of vapor but in this case the results were complicated by the relatively long exposure times compared with the injection times. Cholinesterase determinations carried out on rabbit erythrocytes showed that the Cholinesterase levels dropped precipitously as the P32 concentration in the blood increased.
PARTIAL PURIFICATION OF BOVINE ANTIPLASMIN (ANTIFIBRINOLYSIN)
Authors: Cole Edmond R. , Dalby Arthur , Mertz Edwin T.
Published: December 2009

Bovine antiplasmin (antifibrinolysin) solutions with activities of 12–19 units/mg nitrogen have been obtained from bovine serum by 60% ammonium sulphate precipitation and isoelectric precipitation at pH 5.0 representing approximately a 6-fold purification of antiplasmin from serum. An additional 6.4-fold purification of antiplasmin was obtained by chromatography on a large diameter calcium phosphate gel column. Dialysis and lyophilization of the column eluate caused a 30% loss in activity. The dry antiplasmin was 25 times more potent than serum protein and was stable for 12 months when stored in a desiccator over P2O5 at −10°. Antiplasmin solutions with a specific activity twice that obtained with the large column could be eluted from a small diameter calcium phosphate column, but the activity decreased too rapidly to permit preparation of a lyophilized product.
IN VITRO STUDIES ON THE BIOSYNTHESIS OF UBIQUINONE
Authors: Phillips W. E. J.
Published: December 2009

Radioactive ubiquinone can be isolated from rat liver following intraperitoneal injections of C14-acetate or mevalonic acid. No detectable amount of radioactive ubiquinone could be isolated from liver homogenates, liver slices, or intestinal mucosa incubated in vitro with C14-acetate or mevalonic acid. The possible requirement of isolated tissues for an exogenous factor is discussed.
STIMULATION OF THE FASCICULUS SUBCALLOSUS IN THE CAT WITH IMPLANTED ELECTRODES
Authors: Lamarche Guy , Giguère R. , Langlois J. M.
Published: December 2009

Stimulation of the fasciculus subcallosus in cats with implanted electrodes produced turning of the eyes and head to the opposite side with a tendency to circling. The relation between frontal lobe, fasciculus subcallosus, and caudate nucleus are briefly discussed.
A MOLECULAR MECHANISM FOR ENZYMATIC DEHYDROGENATIONS INVOLVING PYRIDINE NUCLEOTIDES
Authors: Krupka Richard M. , Laidler Keith J.
Published: December 2009

The main kinetic results obtained with the dehydrogenases are briefly summarized. It is shown that the mechanism must involve a ternary enzyme–substrate–coenzyme complex, that acidic and basic groups on the enzyme surface must be involved in the reaction, and that there appears to be a transfer of the substrate from one site to another in the rate-determining step. It is suggested that this step is the actual hydrogen-transfer process. When the substrate is undergoing oxidation, this transfer is brought about by a nucleophilic attack by a basic group B−at the enzyme's active center. This attack may be on a hydroxyl hydrogen atom, and is considered to lead to the transfer of H−from the substrate to the coenzyme. The product is held to the enzyme by hydrogen bonding between the group BH (formed by the addition of a proton to the basic group B−) and the carbonyl group on the substrate.
COMBINED ESTIMATES IN COLORIMETRIC DETERMINATIONS WITH HIGH VARIABILITY
Authors: Anastassiadis P. A.
Published: December 2009

In a number of colorimetric determinations used in biochemistry, the absorbances of replicates are subject to variations. The resulting variability may be time-to-time variability, measured by the intervariance, or variability of simultaneous replicates, measured by the intravariance. In such determinations two estimates of the unknown may be derived according to the standards used, one based on the absorbance of simultaneous standards, a second based on the mean absorbance of all available standards. If intravariance does not exist, the first estimate is the more precise. If intervariance does not exist, the second estimate is the more precise. If both intravariance and intervariance exist, a weighted mean of two estimates, one based on the absorbances of simultaneous standards and a second based on the mean absorbance of all the available non-simultaneous standards, is a value with an increased precision. A method for calculating this value is given.
AMINO ACID ACCUMULATION IN EHRLICH ASCITES CARCINOMA CELLS
Authors: Tenenhouse A. , Quastel J. H.
Published: December 2009

Measurements of the transport of amino acids into Ehrlich ascites carcinoma cells have shown that the following relationship exists between the intracellular steady-state concentration of the amino acid (Cx) and the extracellular concentration (C0):[Formula: see text]where Cmis the maximum intracellular concentration (formed when C0is large) and Emis a constant. It is shown that Emis identical with Km, the Michaelis constant, if a carrier enzyme is involved in the process of active transport and is, therefore, a measure of the affinity of the amino acid for the effective agent involved in the transport phenomenon.The ratio of the steady-state intracellular and extracellular concentrations of amino acids exceeds unity with all amino acids examined. The responses of L-S-ethylcysteine transport to changes of potassium ion concentration and to changes of temperature differ from those of glycine transport and indicate that different carriers are involved in the active transport of these amino acids into Ehrlich ascites cells. This conclusion is supported by the fact that, whereas glycine and L-serine compete with each other for concentrative uptake, such mutual competition does not occur between S-ethylcysteine and glycine or L-serine or L-leucine.Effects of the metabolic inhibitors, 2,4-dinitrophenol, iodoacetate, and stilbestrol show that these substances exercise inhibitory effects on active transport of amino acids by suppression of respiratory or glycolytic energy. Stilbestrol, which is a particularly potent inhibitor, is more effective under aerobic conditions (in the absence of glucose) than under anaerobic conditions (in the presence of glucose). It is reasonable to account for these results on the hypothesis that the carrier responsible for amino acid transport is ATP dependent and that the carrier breaks down, and is no longer available for amino acid transfer, if the ATP content of the cell is depleted.
THE INFLUENCE OF ADRENALECTOMY AND INDIVIDUAL STEROID HORMONES UPON THE METABOLISM OF ACETATE-1-C14BY RAT LIVER SLICES: I. INCORPORATION INTO PROTEINS
Authors: Willmer J. S. , Foster T. S.
Published: December 2009

The influence of the adrenal gland on incorporation of acetate-1-C14into rat liver protein was studied. Cortisone, corticosterone, and deoxycorticosterone were found to increase isotope incorporation in both sham-operated and adrenalectomized groups, while Reichstefn's substance S increased radioactivity in the protein only from sham-operated animals. The effects of the alcohol and acetate forms of cortisone, hydrocortisone, deoxycorticosterone, and Reichstein's substance S were compared.
STEADY-STATE OXIDATION OF GLUCOSE IN THE DIABETIC RAT
Authors: Dow Dorothy S. , Allen C. E.
Published: December 2009

The single intraperitoneal injection of a labelled glucose load has been shown to maintain the specific activities of blood glucose and expired CO2at constant levels for extended periods of time. These plateaus have been established in both the fed control and the fed diabetic rat. The results have been interpreted as indicating the existence of a steady state in the labelled system under study.Measurements have been made of rates of oxidation of glucose-1-C14and giucose-6-C14in diabetic and control rats during this steady state between the specific activities of blood glucose and expired CO2. The results indicate no reduction either for the glycolytic or for the phosphogluconate pathway in the diabetic. No change in the ratio between the oxidative rates for the two pathways has been found.
A COMPARISON OF FREE ADRENAL CORTICAL STEROIDS IN THE BLOOD OF A HIBERNATING AND NON-HIBERNATING MAMMAL
Authors: Denyes Arliss , Horwood Robert H.
Published: December 2009

White rats and hamsters were fasted and exposed to cold (6 ± 1 °C) for various periods of time. The adrenal glands were weighed and adrenal cortical steroids were extracted from the blood for separation by paper chromatography.The adrenal weight was not a reliable index of adrenal cortical activity as measured by the quantities of circulating hormones. Two steroid fractions were separated from rat and hamster blood. The fast component was identified as corticosterone and the slow component as an amorphous fraction.The adrenal cortical response to cold is different in rats and hamsters. The hamster does not have the typical alarm reaction and only trace quantities of hormones are found in the hibernating animal. Within 6 hours of arousal the concentrations of circulating adrenal cortical hormones have increased to or beyond those of the control animals. The changes in circulating adrenal cortical hormones of hamsters exposed to cold for varying periods of time can be correlated with changes in their intermediary metabolism and ion balance.
THE REACTION OF SULPHURIC ACID WITH LYSOZYME AND HORSE GLOBIN
Authors: Habeeb A. F. S. A.
Published: December 2009

Lysozyme and horse globin have been treated with concentrated sulphuric acid to produce the N→O acyl shift. Results showed the reaction to be incomplete. Extensive chemical modification of the tyrosine, phenylalanine, tryptophan, and cystine residues occurs. Peptides obtained by degrading the modified protein with hydroxylamine could not be resolved either by paper chromatography or paper electrophoresis.
THE EFFECTS OF AN ANTIHISTAMINE (PROMETHAZINE) ON THE REACTION OF TENDONS TO TRAUMA–A HISTOLOGICAL STUDY
Authors: Walker F. G. , Bensley Sylvia H. , Lindsay W. K.
Published: December 2009

As a part of a continuing study on the healing of flexor tendons, the effects of an antihistamine–antiserotonin compound (promethazine) were studied in 109 chickens. A form of standard surgical trauma to the intact flexor profundus tendon was devised, and the results of several different methods of administration of promethazine were compared. These studies indicate that minimal surgical trauma applied to an intact flexor tendon produces a marked reaction consisting of a degenerative phase, a phase of dedifferentiation, and a phase of regeneration and maturation. The histological studies reveal that such highly specialized intercellular substances as collagenic fibers and bundles, though non-living, are not inert and permanent structures. They can break down, completely disappear, and be reformed as a result of the reaction to trauma of specialized tenocytes and undifferentiated mesenchymal cells of the tendon and epitenon. The effects of an antihistamine (promethazine) are to prolong the phase of degeneration and loss of differentiation and, upon withdrawal, to accelerate the phase of growth and maturation. These effects vary with the dose and method of administration of promethazine.
A COMPARISON OF PHOSVITINS PREPARED FROM HEN'S SERUM AND FROM HEN'S EGG YOLK
Authors: Mok Chi-Ching , Martin W. G. , Common R. H.
Published: December 2009

A phosvitin has been prepared from the serum of estrogenized laying hens and partially characterized on the basis of its contents of N (12.3%), P (10.1%), serine (31.0%), and tryptophan (0.56%). Examination of this serum phosvitin and a yolk phosvitin preparation for N-terminal groups yielded identical chromatographic patterns. Alanine was the major N-terminal amino acid with minor amounts of N-terminal lysine. The sedimentation constant [Formula: see text], weight-average molecular weight 4.2 × 104(Archibald method), and number-average molecular weight 4.0 × 104(calculated from the tryptophan content) of the serum phosvitin were similar to those of the phosvitin prepared from egg yolk by the same preparative technique. The two preparations behaved similarly when subjected to zone electrophoresis on paper.Zone electrophoretic evidence is submitted for the presence of phosvitin in the supernatant from dilution precipitation of crude lipophosphoprotein from laying hen's serum as well as in the precipitate itself.
THE VALIDITY OF RATES OF GLUCOSE APPEARANCE IN THE DOG CALCULATED BY THE METHOD OF SUCCESSIVE TRACER INJECTIONS: I. EFFECTS OF SURGICAL HEPATECTOMY, EVISCERATION, AND ORDER OF TRACER INJECTION
Authors: Hetenyi Jr. G. , Rappaport A. M. , Wrenshall G. A.
Published: December 2009

The validity of the method of successive tracer injections has been tested in vivo. Changes in the rates of C12-glucose appearance, calculated at each time of injection of a trace amount of C14-glucose as tracer, were compared with the corresponding measured changes in rates of intravenously infused C12-glucose in five hepatectomized and two eviscerated dogs. Computer analysis of all data indicated that three of four large discrepancies between measured and tracer-calculated changes in the rate of C12-glucose appearance were associated with poor performance of experiments. Aside from these discrepancies, the method of successive tracer injections provided grouped absolute values for the changes in calculated rates of C12-glucose appearance in nine other comparisons which were, on the average, 6% higher than the corresponding changes in the measured rate of C12-glucose infusion (S.D. ± 9%). This degree of correspondence was not noticeably affected by the order of tracer injections. The data show some indications of C12-glucose production by the abdominal viscera following hepatectomy. Misrepresentation of tracer-calculated rates of appearance as "turnover rates" is criticized.
EFFECTS OF SINGLE INTOXICATING DOSES OF ETHYL ALCOHOL UPON THE HEPATIC LIPIDS OF RATS
Authors: Gillespie R. J. G. , Lucas C. C.
Published: December 2009

Liver damage due to a single intoxicating dose of alcohol was small in well-nourished, fed rats. Increases in stainable and extractable hepatic lipids were even less in similar rats fasted for 24 hours. The damage was slightly greater following the use of a less adequate ration.
THE ESTIMATION OF LACTATE DEHYDROGENASE ACTIVITY OF HUMAN ERYTHROCYTES
Authors: Birkbeck J. A. , Stewart A. G.
Published: December 2009

The influence of pH, temperature, and the concentrations of substrate, coenzyme, and enzyme on the estimation of the LDH activity of human erythrocytes have been examined. The activity had a broad optimum pH range of 7.0 to 7.8 and was markedly influenced by temperature. The optimum concentrations of pyruvate and DPNH were found to be 1.7 × 10−6and 0.8 × 10−7mole/ml of incubation mixture respectively. A method for the measurement of LDH activity at optimum conditions (except for temperature) is described. The method was satisfactory over a 10-fold range of enzyme concentration. Of the anticoagulants commonly used in clinical laboratories for collecting blood, oxalate was inhibitory and heparin, fluoride, versene, and citrate had no influence on LDH activity. Enzyme stability studies indicated that whole blood at 4 °C and dilute hemolyzate frozen at −10 °C could be kept for 4 weeks without loss of LDH activity. Dilute hemolyzate was less stable than whole blood at the same temperature.
THE VALIDITY OF RATES OF GLUCOSE APPEARANCE IN THE DOG CALCULATED BY THE METHOD OF SUCCESSIVE TRACER INJECTIONS: II. THE INFLUENCE OF INTERMIXING TIME FOLLOWING TRACER INJECTION
Authors: Wrenshall G. A. , Hetenyi Jr. G. , Best C. H.
Published: December 2009

Close agreement has been found between calculated rates of C12-glucose appearance in, and measured rates of infusion of C12-glucose into, the blood plasma of acute surgically eviscerated dogs. The calculated rates were obtained using stated assumptions after allowing intermixing times of 60–120 minutes following single injections of C14-glucose into the blood stream. Under the above circumstances, the residual body tissues, including the kidneys, appear to add very little C12-glucose to that already there when the blood sugar level is maintained at or above normal fasting values. The acute surgical procedures and the removal of adbominal organs result in large decreases in calculated rates of transfer of glucose from the inaccessible to the accessible masses of body glucose. Specific criticisms by others against the validity of tracer-calculated rates of C12-glucose appearance in dogs, based on the slow intermixing of injected tracer-glucose with approximately half of the body glucose, are not supported by the findings of this paper.
CARDIOVASCULAR CHANGES IN NON-SENSITIZED RATS CHRONICALLY TREATED WITH 2-METHYL-9-FLUOROCORTISOL
Authors: Bois P. , Beznák Margaret , Jasmin G.
Published: December 2009

2-Methyl-9-fluorocortisol was injected into intact rats in the absence of NaCl dietary supplements during 8 months. All animals became hypertensive and developed myocarditis, nephrosclerosis, and periarteritis nodosa. There were marked cardiac hypertrophy and arteriolosclerosis of the coronary arteries. Evaluation of the basic and maximum work capacity of the heart revealed that the myocardium was functionally equivalent in the control and treated animals. Consequently, sensitization by the intake of large amounts of NaCl is not indispensable for the production of hypertension and cardiovascular lesions with 2-methyl-9-fluorocortisol. In addition, as revealed by the cardiac function tests used, there is no strict parallelism between histologic and functional impairment of the heart.
QUANTITATIVE CHROMATOGRAPHIC METHODS: PART 5. AN IMPROVED NINHYDRIN–HYDRINDANTIN REAGENT
Authors: Matheson A. T. , Tigane E. , Hanes C. S.
Published: December 2009

An improved ninhydrin–hydrindantin reagent has been developed for the quantitative determination of amino acids and peptides separated on filter paper chromatograms. This represents a modification of a reagent described earlier, which was based in turn upon the well-known solution of Moore and Stein. The present reagent has been in use for several years and has shown the advantages of high stability, extremely low and steady reagent blank values, and approximately stoichiometric yields of Ruhemann's purple for most amino acids. In addition to its use for determinations on excised areas from filter paper chromatograms, conditions are defined for the use of the reagent for determinations of amino acids in solutions.
QUANTITATIVE CHROMATOGRAPHIC METHODS: PART 7. ISOLATION OF AMINO ACIDS FROM SERUM AND OTHER FLUIDS
Authors: Harris C. K. , Tigane E. , Hanes C. S.
Published: December 2009

A method based on the use of miniature ion-exchange columns has been devised for isolating small amounts of amino acids from biological fluids and tissue extracts. The amino acids are isolated virtually free from proteins, sugars, and inorganic cations in a single treatment.Techniques are described for the preparation of solutions of the isolated amino acids for quantitative analysis by paper chromatography.
OXIDIZED PYRIDINE NUCLEOTIDES AND LACTIC ACID IN THE CORNEAL TISSUE OF RABBITS
Authors: Morley Nina H. , Toth Andrew
Published: December 2009

The mean concentrations of oxidized pyridine nucleotides in the corneal epithelium and stroma of rabbits, determined fluorometrically in trichloroacetic acid extracts of scrapings from the frozen tissue, were 637 ± 130 and 58 ± 21 μg of DPN per gram of moist tissue respectively. The epithelial level was comparable to the reported content of some samples of rat liver and retina. The mean concentrations of lactic acid in corneal epithelium and stroma were 996 ± 158 and 771 ± 131 μg per gram of tissue respectively. Results suggested that in the cases of epithelial DPN and stromal lactate there is a slight advantage in using the paired eye as a control over an unmatched eye.
CROSS-RESISTANCE TO CARDIOTOXIC AGENTS
Authors: Selye H. , Bajusz E. , Strebel R.
Published: December 2009

Experiments on rats indicate that, following pretreatment with fluorocortisol and Na-acetate, various stressors (restraint, muscular exercise, cold baths, noradrenaline) produce extensive cardiac necroses and high mortality. Gradual adaptation by pretreatment with restraint, muscular exercise, cold baths, or noradrenaline protects against this cardiac-necrosis-eliciting effect of subsequent restraint. This is considered to be an additional example of "cross-resistance" to a stress-induced lesion and illustrates the nonspecificity of the stress mechanism.In similarly conditioned rats, gavage with oil likewise elicits cardiac necroses, but this effect appears to be due to some specific metabolic action, because as used here, the oil elicits no obvious manifestations of stress, and pretreatment with oil protects only against the cardiac-necrosis-eliciting effect of oil itself and not against that of various stressors.
CONCENTRATION OF CORTICOTROPHIN BY PERCOLATION
Authors: Saffran M. , Muhlstock B. , Caplan Brigitte U.
Published: December 2009

Percolation of commercial anterior pituitary powder with decreasing concentrations of ethanol (95 → 70%) and increasing concentrations of acetic acid (0 → 0.5 M) yielded a peak of corticotrophin activity with 70% ethanol containing 0.5 M acetic acid. The material assayed at about 14 units/mg peptide. Further purification by curtain electrophoresis yielded a preparation with 21 units/mg peptide.
THE INHIBITION BY ACETAZOLEAMIDE OF RENAL PHOSPHATE-ACTIVATED GLUTAMINASE IN RATS
Authors: Beaton John. R.
Published: December 2009

Intraperitoneal injection of acetazoleamide (10 mg/100 g body weight) in rats elicits a decreased activity of renal phosphate-activated glutaminase within 1 to 3 hours, followed by a return to normal activity at 8 hours, an increased activity at 16 hours, and a return to normal activity at 24 hours. Urinary excretion of ammonia in acetazoleamide-treated rats is decreased in the 8-hour period following injection (period of decreased enzyme activity) and increased in the subsequent 16-hour period (period of increased glutaminase activity). The net effect is increased urinary excretion of ammonia during the 24-hour period. Acetazoleamide inhibits renal phosphate-activated glutaminase in vitro, 100% inhibition being attained with an inhibitor: substrate ratio 3:1. Inhibition by acetazoleamide in vitro is eliminated with increasing L-glutamine concentration, 100% restoration of activity occurring with an inhibitor: substrate ratio of 1:3. Acetazoleamide had no significant effect upon hepatic phosphate-activated glutaminase and arginase activities in vivo nor upon urinary excretion of urea.