bluuebunny/crossref_metadata_2025 huggingface dataset:
POSTNATAL CHANGES IN β-GALACTOSIDASE ACTIVITY IN THE JEJUNUM AND ILEUM OF MICE, RABBITS, AND GUINEA PIGS
Authors: Koldovský O. , Heringová A. , Jirsová V. , Chytil F. , Hošková J.
Published: December 2009

During the postnatal development of mice, intestinal β-galactosidase activity (0.001 M o-nitrophenyl β-D-galactoside as substrate) is always higher at pH 3.5 than at pH 5.5. In the jejunum a steady decrease of activity during postnatal development is evident, whereas in the ileum the activity increases temporarily and later decreases. The changes in rabbits are more complicated. At pH 5.5 there is a steady decrease of β-galactosidase activity in the ileum and jejunum, but at pH 3.5 there is a steady decrease in activity in jejunum only; in ileum, first an increase is observed and then a decrease. In guinea pigs the activity in newborn animals is relatively very low, and only a small decrease during postnatal development is found. During postnatal development, the activity decreases less at pH 3.5 than at pH 5.5. In contrast to mice and rabbits, guinea pigs showed no substantial differences between jejunum and ileum in all the age groups studied.The results are discussed from the point of view of significance of differences between the jejunum and the ileum, and the existence of several types of β-galactosidase activity.
THE ESTIMATION OF ADENINE NUCLEOTIDES IN RAT UTERUS BY THIN-LAYER CHROMATOGRAPHY
Authors: Carroll P. M. , Graham J. C.
Published: December 2009

A simple method was developed for the estimation of the small amounts of adenosine triphosphate and adenosine diphosphate present in a single rat uterus. The tissue extract was found to adsorb added adenosine triphosphate and adenosine diphosphate, thus giving low recoveries of these nucleotides. This adsorption was overcome by the use of an acidic solution. Thin-layer chromatography was used to effect the separation of the nucleotides. The results obtained by this method are similar to those of investigators who have used other methods.
THE STABILIZATION OF HEPATIC GLYCOGEN SYNTHETASE AT 37 °C BY GLUCOSE-6-PHOSPHATE AND ANAEROBIOSIS
Authors: Weldon Peter R. , Rubinstein David
Published: December 2009

The effect of glucose-6-phosphate, anaerobiosis, and mercaptoethanol upon inactivation at 37° of hepatic UDPglucose: glycogen α-4-glucosyltransferase (EC 2.4.1.11) (glycogen synthetase) was studied. A rat liver preparation, consisting of glycogen granules with some microsomal contamination, was used. During the first 20 minutes of aerobic or anaerobic incubation at 37° the activity of the synthetase falls sharply. When 0.01 M glucose-6-phosphate is present initially under aerobic conditions, a transient stabilization of the enzyme activity occurs. Incubation in an atmosphere of nitrogen results in a prolonged stabilization, after the initial decrease of the enzyme activity. Incubation of the enzyme preparation under anaerobic conditions (N2) in the presence of 0.01 M glucose-6-phosphate prevents loss of enzyme activity for the entire 90-minute incubation period. However, most of the added glucose-6-phosphate is hydrolyzed within the first 10 minutes of incubation. The effect of N2is reproduced to a large extent by mercaptoethanol, but the effect of these two agents is not additive. It is concluded that inactivation of the enzyme at 37° is partially due to the aerobic oxidation of —SH groups of the enzyme.
EFFECTS OF PYRIDOXINE DEFICIENCY AND DIETARY CHOLESTEROL SUPPLEMENTATION IN THE CHICK ON PLASMA PROTEIN-BOUND IODINE, GLUTAMIC–OXALACETIC TRANSAMINASE ACTIVITY, AND 14C-ACETATE INCORPORATION INTO CHOLESTEROL
Authors: Lupien P. J.
Published: December 2009

The influence of B6 avitaminosis and the feeding of cholesterol on protein-bound iodine (PBI) of plasma and plasma glutamic–oxalacetic transaminase (PGOT) levels of chicks was studied, and the findings related to relative rates of 14C-acetate incorporation into plasma and liver cholesterol of chicks 3, 5, 11, and 15 days old.High plasma cholesterol levels were noted in the 11-day-old vitamin B6-deficient chicks. Liver cholesterol levels of this group were not significantly altered. Dietary cholesterol added at a level of 1% significantly increased liver and plasma cholesterol levels of the cholesterol-fed control and vitamin B6-deficient chicks; it also inhibited 14C-acetate incorporation into plasma and liver cholesterol to a much greater extent than did simple B6 avitaminosis or exogenous cholesterol per se. PBI parameters for control and vitamin B6-deficient chicks resembled those of plasma and liver cholesterol specific activity curves during the experimental period. Decreased PBI levels were noted 8 days after the beginning of the experiment in the vitamin B6-deficient birds. Dietary cholesterol significantly decreased PBI levels of 11-day-old control birds but increased it markedly 4 days later. PBI levels of the 11-day-old cholesterol-fed birds deficient in vitamin B6 were not changed, but were significantly increased 4 days later. PGOT levels were highest in 3-day-old control birds, and decreased rapidly thereafter. PGOT levels of the vitamin B6-deficient chicks were significantly decreased 3 to 4 days after the beginning of the experiment. The supplementary dietary cholesterol increased PGOT levels of 15-day-old cholesterol-fed control birds, but decreased PGOT levels of cholesterol-fed chicks deficient in vitamin B6. Although preliminary, these observations suggest an interrelationship between pyridoxine, thyroxine, and the mechanism responsible for the synthesis of cholesterol.
AN IMPROVED PREPARATIVE METHOD FOR D-ERYTHROSE 4-PHOSPHATE
Authors: Sieben A. S. , Perlin A. S. , Simpson F. J.
Published: December 2009

The oxidation of 1 mmole of D-glucose 6-phosphate with 1.7 mmoles of lead tetraacetate admixed with 1.8 mmoles of sulfuric acid yields a preparation containing 0.77 mmole of D-erythrose 4-phosphate and 0.20 mmole of unoxidized glucose 6-phosphate. The D-erythrose 4-phosphate is separated from the D-glucose 6-phosphate by chromatography on Dowex 1-formate, and recovered as the barium salt of the hydrazone in 50% yield. Evidence is presented that erythrose 4-phosphate may exist in monomeric and dimeric forms. Glucose 6-phosphate and erythrose 4-phosphate produce different colors in the phenol – sulfuric acid reaction. This can be used for the qualitative identification and quantitative determination of these sugar phosphates.
MODE OF ACTION OF CHOLINE: I. FATTY ACID COMPOSITION OF LIVER, SERUM, AND ADIPOSE TISSUE OF CHOLINE-DEFICIENT RATS
Authors: Chalvardjian A.
Published: December 2009

Young albino rats were fed choline-deficient and choline-supplemented diets, fat-free and containing two different levels of fat (4%, 30%), for 2 weeks. The fatty acid pattern of the major lipid fractions of liver, serum, and adipose tissue was determined by thin-layer and gas–liquid chromatography. It was found that (a) no quantitative similarities in fatty acid pattern existed between hepatic triglycerides on the one hand and adipose tissue, serum triglycerides, and dietary fat on the other, but the fatty acid composition of hepatic triglycerides bore a closer resemblance to that of dietary fat when the latter was increased to 30%; (b) under the conditions of this experiment, the level of dietary fat had a more marked effect on altering the fatty acid composition of tissues, especially the triglyceride fraction, than the level of choline in the diet; and (c) a relative preponderance of 16-carbon fatty acids occurred in hepatic triglycerides of choline-deficient animals fed the fat-free and low-fat diets.
ENZYMIC ACTIVITIES IN PRE-RIGOR AND POST-RIGOR SARCOPLASMIC EXTRACTS OF CHICKEN PECTORAL MUSCLE
Authors: Neelin J. M. , Ecobichon D. J.
Published: December 2009

It was confirmed that myogen (extracted in hypotonic salt solutions) and sarcoplasm (obtained by gentle homogenization in hypertonic sucrose solutions) from chicken pectoral muscle differ in content of certain cationic components. One of the proteins reduced in sarcoplasm was identified as the lactate dehydrogenase isozyme characteristic of skeletal muscle, and it exhibited changes in recovery and activity consistent with the sequence reported for sarcoplasmic proteins through rigor and postmortem "aging". At the same time the distinction between two esterase zones, specific respectively for myogen and for sarcoplasm, tended to be obliterated. Electrophoretic patterns and activities of malate dehydrogenase, isocitrate dehydrogenase, alkaline phosphatase, and acid phosphatase showed no specific dependence on conditions of extraction or of aging. These observations are discussed in terms of possible associations between these components and intracellular structures, notably lysosomes and sarcoplasmic reticulum, which may be labilized by incipient autolysis, ultimately manifest as "tenderization" of the muscle tissue.
DETERMINATION OF ACID PHOSPHATASE ACTIVITY IN TISSUE HOMOGENATES
Authors: Manning John P. , Babson Arthur L. , Butler Margaret C. , Priester Sara F.
Published: December 2009

A simple and accurate method is described for the quantitative determination of acid phosphatase in tissue homogenates, utilizing stable buffered sodium α-naphthyl acid phosphate tablets as substrate, and the monocoupler Fast Red Salt B as the color developer. This technique eliminates deproteinization and ethyl acetate extraction, and produces a highly colored blue azo dye for spectrophotometry. Of the rat organs tested, the spleen had the highest acid phosphatase activity, then kidney, small intestine, liver, lung, and heart, in that order.
TERATOGENIC COMPOUNDS OF VERATRUM CALIFORNICUM (DURAND): II. PRODUCTION OF OVINE FETAL CYCLOPIA BY FRACTIONS AND ALKALOID PREPARATIONS
Authors: Keeler Richard F. , Binns Wayne
Published: December 2009

Certain fractions as well as glycosidic and parent alkamine alkaloid preparations derived from the plant Veratrum califomicum were shown to produce ovine fetal cyclopia. Other Veratrum preparations were also tested for teratogenicity. A mechanism for the teratogenic effect is postulated.
NUCLEIC ACID SYNTHESIS IN X-IRRADIATED THYMOCYTES
Authors: Myers D. K. , Skov Kirsten
Published: December 2009

The rate of incorporation of thymidine into the deoxyribonucleic acid (DNA) of rat thymocytes in vitro was not immediately affected by low doses of X-radiation, but became progressively more inhibited as the irradiated cells were incubated at 37 °C for periods of up to 6 hours. Ribonucleic acid (RNA) synthesis deteriorated almost at the same rate as DNA synthesis after X-irradiation in vitro, but protein synthesis was slightly more resistant. Addition of 10–50 mM nicotinamide to the irradiated cell suspensions tended to retard the development of this inhibition, particularly at low temperatures, but high concentrations of nicotinamide were also toxic to these cells. The inhibition of DNA synthesis by X-irradiation appeared to follow a qualitatively similar pattern in thymus, spleen, and regenerating liver in vivo.In addition to the inhibition resulting from degenerative processes in the irradiated cells, DNA synthesis in vitro was directly inhibited by 20–30 kr X-radiation. The effects of radiation on DNA synthesis paralleled to some extent its effects on the gel-forming capacity of the deoxyribonucleoprotein from the thymus cells. It is suggested that the normal synthesis of both RNA and DNA in thymocytes depends on the integrity of the deoxyribonucleoprotein.
SPECIES, TISSUE, AND INDIVIDUAL SPECIFICITY OF LOW IONIC STRENGTH EXTRACTS OF AVIAN MUSCLE AND OTHER ORGANS REVEALED BY STARCH-GEL ELECTROPHORESIS
Authors: Baker C. M. Ann
Published: December 2009

The proteins soluble at low ionic strength of various muscles and of other tissues from five species of birds were examined by vertical starch-gel electrophoresis. The methods used were simple, and gave excellent and repeatable electrophoretic resolution of proteins. Most samples yielded 15–25 zones which stained nonspecifically for protein. Histochemical techniques revealed additional, enzyme, bands which were not coincident with the "major" protein zones. The results confirm and extend previous observations of the species specificity of the electrophoretic profiles of proteins from muscle extracts (myogen), and reveal considerable tissue and individual specificity of the enzymes and other proteins in extracts of avian tissues.
CARBOXYLATION OF CROTONYL-CoA BY MAMMALIAN ENZYME SYSTEMS
Authors: Tustanoff E. Reno , Stern Joseph R.
Published: December 2009

In a crude dialyzed ammonium sulfate fraction (35–65% saturation) of rat liver, carbon dioxide fixation into crotonyl-CoA took place when the test system was supplemented with ATP, Mn++, glutathione, Tris–HCl buffer (pH 7.0), and KH14CO3. The products of this reaction were identified after hydrolysis as glutaconic, β-hydroxyglutaric, maionic, and 2-ethylmalonic acids. The isolation and characterization of 5-14C-glutaconyl-CoA indicated a γ-carboxylation reaction. In the presence of endogenous enoyl-CoA hydratase, crotonyl-CoA was carboxylated more readily than β-hydroxybutyryl-CoA, suggesting that the unsaturated acyl compound was the natural substrate for the enzyme system. Carboxylation of crotonyl-CoA was greatly enhanced when liver extracts were prepared from either fasted or alloxan-diabetic rats. Fixation of carbon dioxide into crotonyl-CoA was also demonstrated with an amorphous preparation of propionyl-CoA carboxylase from pig heart. The products of this reaction were identified as radioactive malonic acid and unlabeled acetaldehyde, compounds which resulted from the alkaline hydrolysis of 2-ethylidenemalonyl-CoA, formed by the α-carboxylation of crotonyl-CoA. Evidence is presented that both α- and γ-carboxylation are catalyzed by the crude liver preparation.
INTRACELLULAR DISTRIBUTION AND SOME PROPERTIES OF HEXOKINASE OF BOVINE ADRENAL MEDULLA
Authors: Toews C. J.
Published: December 2009

The intracellular distribution of the hexokinase of the adrenal medulla was studied. Most of the hexokinase was found, in about equal amounts, in the mitochondria and the nonparticulate cytoplasm. The amount of hexokinase associated with the mitochondria was shown to be dependent on the hexokinase concentration in the medium surrounding the mitochondria.The hexokinase of the adrenal medulla was shown to be noncompetitively inhibited by adenosine diphosphate (ADP) with respect to glucose and adenosine triphosphate (ATP). It was competitively inhibited with respect to glucose by mannose, fructose, and galactose. Glucose-6-phosphate (0.09 M) did not inhibit the hexokinase. The data on product inhibition and initial velocity analysis support the concept of an ordered sequential mechanism for adrenal-medulla hexokinase.
HEXOSAMINE, SIALIC ACID, FUCOSE, SEROMUCOID, AND PROTEIN LEVELS OF SERA OF SOME SPECIES
Authors: Grant D. L. , Dale D. G. , Anastassiadis P. A.
Published: December 2009

The levels of hexosamine and protein in human, rodent, bovine, porcine, and ovine sera, and the levels of sialic acid, fucose, seromucoid hexosamine, and seromucoid sialic acid in bovine, porcine, and Ovine sera were determined for a number of animals of different groups. In the porcine sera the levels of hexosamine, fucose, and seromucoid hexosamine and sialic acid were higher than in the sera of the other animals. The sera of bovine, porcine, and ovine immature animals contained significantly less protein and fucose than the sera of mature animals. In cows and pigs two and a half times more hexosamine and twice as much sialic acid were present in the seromucoid fraction isolated from the sera of immature than from the sera of mature animals. Some other differences between immature and mature animals were detected.The effect of chronic fluorosis on the hexosamine and protein contents of bovine serum was studied. Statistically significant depression of both serum hexosamine and protein in the animals affected by chronic fluorosis was observed. Some other conditions influencing the serum hexosamine and protein were investigated.
EXCRETION OF BILE ACIDS BY THREE MEN ON A FAT-FREE DIET
Authors: Ali S. S. , Kuksis A. , Beveridge J. M. R.
Published: December 2009

A combination of thin-layer chromatography and gas–liquid chromatography was used for the separation and determination of fecal bile acids in three middle-aged men during the last 4 days of three 8-day periods on a fat-free diet. The range of the total output was 130–650 mg/day. Lithocholic and deoxycholic acids were the major components and accounted for 65–80% of the total excretion of bile acids. Other common bile acids were present in considerably smaller quantities (0.5–11% each). In addition, evidence was obtained for the presence of a number of as yet unreported fecal bile acids. These were tentatively identified as 3α,12β-dihydroxy-, 3β,12β-dihydroxy-, 3α,7β-dihydroxy-, 3α-monohydroxy-7-keto-, 12α-monohydroxy-3-keto-, and 7β-monohydroxy-cholanic and cholanic acids. The latter three acids occurred in traces only, but the other uncommon fecal bile acids each accounted for 0.5–7% of the total excretion of bile acids. Significant variations were found in the concentrations of several of the bile acids both between different samples from the same subject and between samples from different subjects.
GLYCOLYTIC METABOLITES AND THEIR DISTRIBUTION AT DEATH IN THE WHITE AND RED MUSCLE OF COD FOLLOWING VARIOUS DEGREES OF ANTEMORTEM MUSCULAR ACTIVITY
Authors: Fraser Doris I. , Dyer W. J. , Weinstein H. M. , Dingle J. R. , Hines J. A.
Published: December 2009

Muscular activity just before death critically affected the levels of glycolytic metabolites in the skeletal muscle of feeding, aquarium-held cod. Relaxed cod could be obtained by slow anesthetization without visible excitation; these contained very little lactate in the white muscle (7–28 mg/100 g), and exhibited high, uniformly distributed levels of high-energy phosphate compounds (about 17 μmoles acid-labile P/g plus equal or higher amounts of creatine phosphate). A trend to lower glycogen levels in the anterior portion of the fillet was indicated. Unexercised fish caught and killed with negligible struggling appeared to have undergone some antemortem activity. Compared with relaxed cod, they showed higher lactate levels (about 100 mg/100 g), much lower levels of creatine phosphate and other high-energy phosphate compounds, together with some ammonia. Again, glycogen was lower in the anterior than in the posterior portion. Exhaustion uniformly depleted energy reserves to low levels in the white muscle; in the red muscle, however, high glycogen levels were maintained, although the content of other glycolytic metabolites indicated partial activation of the glycolytic processes during the antemortem struggle. In all fish examined, levels of inorganic and total acid-soluble phosphorus were lower in the red than in the white muscle.
TOXOHORMONE IN BACTERIA-FREE TUMORS
Authors: Nixon J. C. , Zinman B.
Published: December 2009

Toxohormone was extracted from bacteria-free human tumors and normal tissues, and assayed for activity by measuring the decrease in serum iron levels of rats 12 hours after injection of the extracts. In contrast with the findings of others, the results of the present study demonstrated that active toxohormone could be isolated from bacteria-free tumor tissues. Bacteria-free normal human kidney and spleen also yielded active toxohormone extracts, whereas extracts of normal human- and rat-skeletal muscle and rat liver had no activity.Four active toxohormone extracts were purified by ion-exchange chromatography followed by gel filtration. Human leukemic spleen, metastatic carcinoma of the cecum, and normal human spleen and kidney yielded several highly active purified fractions.
SEPARATION AND PROPERTIES OF PIG-SERUM LIPOPROTEINS
Authors: Janado M. , Martin W. G. , Cook W. H.
Published: December 2009

Pig serum contained three major classes of lipoproteins resembling the very low density (VLDL), low density (LDL), and high density lipoproteins (HDL) found in human serum but in smaller amounts. The LDL class had two clearly resolved components (LDL1and LDL2) that were separated by differential centrifugation at solvent densities of 1.060 and 1.090. Heterogeneity in density was evident in all fractions, especially in those of highest lipid content. Average molecular weights and lipid contents of the isolated fractions were: VLDL, 17 × 106and 90%; LDL1, 3 × 106and 79%; LDL2, 2 × 106and 72%; and HDL, 0.25 × 106and 51%. Apart from small differences in proportion, the lipoproteins in the pooled samples collected over an 18-month period were quite similar although more extensive measurements may reveal differences. The presence of these distinct and separable lipoprotein fractions suggest structural differences worthy of further study.
SOLUBILIZATION AND HETEROGENEOUS NATURE OF PROTEINS FROM RIBOSOMES OF PEA-SEEDLING BUDS
Authors: MacQuillan A. M. , Bayley S. T.
Published: December 2009

The results of several procedures for solubilizing protein from pea-seedling ribosomes are described. Pancreatic ribonuclease (RNAase), alone at pH 8.0 and low ionic strength, solubilized 10%, whereas subsequent treatment with dilute HC1 solubilized a further 29%. RNAase in 8 M urea at pH 5.5 solubilized more than 90% of the ribosomal protein. After removal of ribonucleic acid fragments, all of this material, termed "total protein", remained in solution in 0.05 M acetate buffer at pH 5. Proteins solubilized by these three procedures were subjected to electrophoresis on starch–urea gels, amino acid analyses, and fingerprinting after digestion with trypsin and chymotrypsin. The protein soluble in RNAase probably contains only one or two components and is distinct in amino acid and peptide composition from the remainder of the ribosomal protein. Protein soluble in HC1 is representative of much of the "total protein" and both HC1-soluble and "total protein" are complex. Fingerprints showed that although RNAase-extracted protein and three fractions of "total protein" obtained by gel electrophoresis were different, they also possessed a number of peptides in common. It was concluded that the number of components in pea-ribosomal proteins is probably of the order of 16, the number of bands seen in gel-electrophoretic patterns.
AGENTS AFFECTING LIPID METABOLISM: XXIII. THE EFFECT OF AN INHIBITOR OF CHOLESTEROL BIOSYNTHESIS ON THE INCORPORATION OF PRECURSORS OF PHOSPHATIDES IN RAT SERUM AND TISSUES
Authors: Hill P. , Rochefort J. G.
Published: December 2009

The biosynthesis of phosphatides in rat tissues was investigated with mixtures of choline-Me-14C and palmitic acid-9,10-3H, and dl-serine-3-14C and palmitic acid-9,10-3H respectively. Labeled choline and palmitic acid were incorporated at different rates into N-base and acyl moieties of phosphatides in the tissues, including the brain. Comparison of the specific activity of β-fatty acids of phosphatidyl ethanolamines (PE) and phosphatidyl cholines (PC), labeled with3H derived from palmitic acid, indicated that either the two phosphatides were synthesized from different pools of diglycerides, or that the acyl β-transferases involved in the synthesis of PE and PC had different rates of incorporation.In rats fed a cholesterol biosynthesis inhibitor, AY-9944, the specific activity of β-fatty acids in PE and PC was reduced in the tissues, notably in the lungs. The incorporation of labeled choline was also reduced in the tissues. Except in the lungs, AY-9944 reduced the incorporation of labeled palmitic acid and choline into tissue sphingomyelins to a different degree. Evidence suggested that AY-9944 affected either diglyceride formation or the acyl β-transferases, or both. Furthermore, the alteration in diglyceride, or a more direct effect of AY-9944 on the incorporation of choline via cytidyl phosphorylcholine, resulted in a reduction of incorporation into the N-base moiety.
THE RESPIRATORY DEPENDENT SWELLING OF LIVER MITOCHONDRIA
Authors: Cereijo-Santaló Roberto
Published: December 2009

The respiratory dependent swelling of isolated rat liver mitochondria was studied in sucrose and in potassium chloride media.In a sucrose medium it was found that mitochondria did not swell in the absence of respiration over the pH range 7.0–8.0. However, swelling of mitochondria readily occurred during the oxidation of endogenous or added respiratory substrates. Maximum rates of swelling at pH 7.0 were observed with ascorbate, reduced glutathione, and reduced nicotinamide–adenine dinucleotide (NADH). The swelling induced by substrate oxidation in a sucrose medium was markedly inhibited by the addition of KCl.In a KCl medium, mitochondria swelled in the absence of respiration at acid (6.0) and at alkaline (8.0) pH values, but were stable at pH 7.0–7.4. Endogenous respiration did not modify these results. The addition of β-hydroxybutyrate induced maximum swelling at pH 7.0. The extent of swelling produced by this substrate diminished when either the pH or the molarity of the buffer was increased. Ascorbate and reduced glutathione failed to induce swelling in a KCl medium. NADH in a KCl medium produced swelling to about the same extent as that in a sucrose medium. However, the onset of the swelling was delayed in the KCl medium. This lag period was shortened by the addition of rotenone and it was lengthened when either the molarity or the pH of the buffer was increased.An attempt has been made to relate these results to proton pressure produced in the mitochondrial membranes during electron transport.
THE EFFECT OF OXYPHENBUTAZONE (TANDEARIL) ON THE LEVEL OF THE SEROMUCOID FRACTION OF RATS BEARING WALKER 256 CARCINOMA
Authors: Macbeth R. A. , Martin F.
Published: December 2009

The effect of oxyphenbutazone (Tandearil) on the seromucoid protein and seromucoid-bound carbohydrates of Walker 256 carcinoma bearing rats has been investigated. Initially, treatment is associated with increased tumor growth and suppression of the anticipated glycoprotein response in the serum. After the eighth day, tumor growth ceases in treated animals and the serum glycoproteins manifest progressive elevations which are, however, less than those observed in untreated tumor-bearing controls. The survival time of treated animals exceeded that of untreated tumor-bearing animals, and treated animals were free of gross malignant disease at the time of death.
MULTIPLE FORMS OF LACTATE DEHYDROGENASE AND ASPARTATE AMINOTRANSFERASE IN HERRING (CLUPEA HARENGUS HARENGUS L.)
Authors: Odense Paul H. , Allen Theresa M. , Leung Ted C.
Published: December 2009

The distribution of isoenzymes of lactate dehydrogenase (LDH) and aspartate aminotransferase (AAT) in the tissues of 189 herring (Clupea harengus harengus L.) were examined. Starch-gel electrophoresis of the LDH isoenzymes of the herring revealed the presence of two hybrid forms representing mutant alleles at the B locus. These mutants gave rise to two genotypes, BB′ and BB″, whose LDH staining patterns revealed a binomial distribution of the tetramer combinations formed from a free and random association of the A, B, and B′, and the A, B, and B″ monomers respectively.A hybrid form of soluble AAT was found. Its electrophoretic pattern showed a 1:2:1 binomial distribution of bands. It is postulated that these bands represent AAT dimers formed from normal S and mutant S′ monomers of a heterozygous SS′ genotype. The normal homozygous SS genotype showed only one band of activity.The normal levels of LDH and AAT activity in plasma and in heart and skeletal muscles were determined. During frozen storage LDH-5 activity gradually disappeared, while LDH-1 activity changed least; LDH-1 was also most stable at higher temperatures. Frozen storage rapidly destroyed AAT activity.
EFFECT ON THE RAT PANCREAS OF FEEDINGDL-ETHIONINE, WITH AND WITHOUT ADENOSINE TRIPHOSPHATE, FOR 1 TO 10 DAYS
Authors: Lyman R. L. , Thenen Shirley , Tucker Robert
Published: December 2009

Previous investigations had suggested that DL-ethionine stimulates synthesis of pancreatic enzymes in rats. To learn more about the mechanism of this apparent effect of ethionine on the pancreas, a study was conducted in which rats were fed a low-protein diet containing 0.25% DL-ethionine. Resting and stimulated pancreatic enzyme activities were compared with control values and with those from another group fed ethionine and injected daily with 125 mg adenosine triphosphate (ATP). Rats fed the ethionine diet for 10 days lost nearly all of their pancreatic enzyme activities, and when they were fasted the enzyme levels were not restored. Administration of ATP did not prevent this effect of ethionine. Rats fed ethionine alone or with ATP for 1 day had twice the pancreatic lipase activity as the controls. When the pancreases of these animals were stimulated to secrete, enzyme discharge in response to the stimulus was delayed, and intestinal enzyme activities remained lower than in controls. Pancreatic enzyme activities increased above those of control rats within 6 hours after the ethionine diet was fed. The high enzyme activities in these animals after 1 day on ethionine appeared to have resulted, therefore, from impaired secretion of the enzymes rather than from increased enzyme synthesis. ATP failed to counteract the ethionine-induced pancreatic damage in either the short-term or 10-day experiments.
THE LIMITED RELEASE OF RIBOSOMAL PEPTIDASE DURING FORMATION OF ESCHERICHIA COLI SPHEROPLASTS
Authors: Matheson A. T. , Murayama T.
Published: December 2009

When lysozyme–EDTA spheroplasts are formed from Escherichia coli cells, only a small fraction of the total peptidase activity of the cell is released into the supernatant fluid under conditions where ribonuclease is quantitatively released. Purification of the released peptidase on DEAE-Sephadex gives two fractions. The peptidase in one fraction shows the same substrate specificity, metal ion requirements, and chromatographic properties as the ribosomal peptidase of the cell; the peptidase in the other fraction shows the same properties as the soluble peptidases of the cell. The ribosomal peptidase does not belong to the group of hydrolytic enzymes that are released when E. coli cells are converted into spheroplasts.
INHIBITORS OF NUCLEOSIDE METABOLISM
Authors: Paterson A. R. P. , Simpson A. I.
Published: December 2009

When incubated with hypoxanthine and guanosine, intact human erythrocytes synthesize inosine, which appears in the incubation medium. This system was employed to test 143 variously substituted purines and purine analogues as potential inhibitors of nucleoside metabolism; 26 inhibitory compounds were detected, all of which inhibited inosine synthesis by intact erythrocytes, but failed to inhibit the same reaction in preparations of disrupted erythrocytes. These compounds also inhibited the uridine-supported synthesis of inosine by intact Ehrlich ascites tumor cells in vitro.Most of these inhibitors were 6-mercaptoethers of purine (or 2-aminopurine) ribonucleoside. A wide variety of substituent groups on the sulfur atom, ranging from methyl (but not hydrogen) to p-nitrobenzyl, imparted inhibitory activity. 2-Arnino-6-(p-nitrobenzylmercapto) purine ribonucleoside, the most effective agent found, inhibited inosine synthesis by 74% when the ratio of guanosine concentration to that of inhibitor was 1000.Compounds with important inhibitory activity had particular substituent groups at both positions 6 and 9 on the purine ring; if present separately, the active substituent groups imparted much less inhibitory activity than when present together on the same molecule. The only 6-position substituents found to impart inhibitory activity were mercapto, chloro, and iodo groups. Ribosyl, arabinosyl, tetrahydro-2-pyranyl, and n-butyl substituents at position 9 produced inhibitory compounds when a 6-mercaptoether substituent was present.
STUDIES ON SOLUBILIZED ADENYLATE KINASE FROM MITOCHONDRIA
Authors: Brewster Marjorie A. , Younathan Ezzat S.
Published: December 2009

Adenylate kinase from mitochondria of rat liver was made soluble by sonication. The enzyme had a pH optimum of 8.0, temperature optimum of 30°, and activation energy of 12.2 kcal/mole. It was activated by several divalent cations in the following order of efficiency: Mg++ > Co++ > Mn++ > Ca++, with an optimal Mg++: ADP ratio of 1. The apparent Km value (ADP as substrate) was found to be 1.3 mM at pH 7.4 and 30°. The activity was sensitive to phloretin and mildly activated by aurovertin. Oligomycin, 2,4-dinitrophenol, p-chloromercuribenzoate, alloxan, and phlorizin had no effect on the activity. The metabolic function and a comparison of the properties of this solubilized mitochondrial adenylate kinase with those of similar preparations from other sources are discussed in the light of these findings. During this study, a sensitive method adaptable for a large number of assays of adenylate kinase was developed, and is described in detail.
EFFECTS OF PHENOTHIAZINES ON GROWTH, GLUCOSE UPTAKE, AND CELL COMPOSITION IN TETRAHYMENA PYRIFORMIS W
Authors: Rogers C. G.
Published: December 2009

The effect of phenothiazine derivatives on growth, glucose uptake, and cell composition was studied in the ciliate protozoan Tetrahymena pyriformis W. The most effective inhibitor of growth in a chemically defined medium was promazine (PRZ), followed by chlorpromazine (CPZ), promethazine (PMZ), prochlorperazine (PCP), acetophenazine (ACP), and trifluoperazine (TFP). The uptake of glucose was highest in resting suspensions of cells in the logarithmic phase (40 hours), but decreased with increasing age of the culture. Little or no uptake of glucose occurred in cells pre-inhibited by PRZ or CPZ. The most effective inhibitor of glucose uptake was TFP, followed by ACP, PCP, PRZ, CPZ, and PMZ. The concentration of protein in cells grown with Tween 80 was unaffected by PRZ, although total cell populations were reduced. Under these conditions, PRZ or CPZ delayed the accumulation of lipid in the cells. Similarly, PRZ reduced the amount of RNA and DNA during the logarithmic phase.These results demonstrated that phenothiazine derivatives can influence lipid and nucleic acid levels in Tetrahymena, and further suggest that the drugs may interfere directly with the mechanism of glucose transport into the cell. These observations support the hypothesis that metabolic effects are related to the ability of phenothiazine derivatives to alter permeability of cell membranes.
IN VIVO SYNTHESIS AND BREAKDOWN OF DEOXYRIBONUCLEIC ACID IN TRIBOLIUM CONFUSUM DUVAL
Authors: Chaudhary K. D. , Lemonde A.
Published: December 2009

The in vivo synthesis of deoxyribonucleic acid (DNA), as shown by the rate of incorporation of14C-thymidine, has been investigated at different stages in the life cycle of Tribolium confusum. During the larval period, a close similarity is observed between the rate of DNA synthesis and the pattern of growth. The pupal stage, which is a non-growth phase, is characterized by a cessation of DNA synthesis. During the larval growth phase, although the 3-day-old larvae have the lowest and the 13-day-old have the highest rate of DNA synthesis, the rate of DNA degradation in the older larvae is almost twice as great as that of the younger larvae. These findings are consistent with the observed total concentration of DNA of the insect at these stages.
THE METABOLISM OF CATECHOLAMINES IN HYPERTHYROID AND VITAMIN B12 DEFICIENT RATS
Authors: Proulx L. , D'Iorio A. , Beznak M.
Published: December 2009

The effect of hyperthyroidism and vitamin B12 deficiency was studied on liver monoamine oxidase, liver catechol-O-methyl transferase, and the noradrenaline and adrenaline content of liver, heart, and brain. In the hyperthyroid rats, there was a 25% decrease in liver monoamine oxidase and this decrease does not appear to be related to a decrease in body weight. Liver catechol-O-methyl transferase activity was normal in hyperthyroid animals. The noradrenaline and adrenaline content of liver, heart, and brain were also not modified. Vitamin B12 deficiency did not affect catechol-O-methyl transferase activity but hepatic monoamine oxidase was lower by 20–30% in rats supplemented with the vitamin. In vitro, vitamin B12 and methyl cobalamin did not modify the activity of catechol-O-methyl transferase in concentrations ranging from 1 × 10−3 M to 1 × 10−6 M. Vitamin B12 also did not affect monoamine oxidase activity at concentrations of 1 × 10−4 M to 1 × 10−5 M.
KINETICS OF THREONINE DEAMINASE OF ESCHERICHIA COLI K-12 AND A STREPTOMYCIN-DEPENDENT MUTANT
Authors: Desai I. D. , Polglase W. J.
Published: December 2009

The relation between threonine deaminase activity and threonine concentration in sonic extracts of wild-type and streptomycin-dependent Escherichia coli K-12 was found to follow a hyperbolic curve. A similar relationship was obtained between enzyme activity and pyridoxal concentration. However, when serine was used as substrate, the activity–concentration curve was sigmoid, suggesting that serine may be a weaker effector of allosteric transition than threonine. The kinetic properties of the (derepressed) threonine deaminase of streptomycin-dependent E. coli K-12 were found to be similar to those of the enzyme of the wild-type K-12.It is postulated that derepression of threonine deaminase in streptomycin-dependent E. coli K-12 provides a selective advantage which permits exponential growth of this mutant in the presence of L-valine, which is an excretory product of streptomycin-dependent microorganisms.
DEOXYRIBONUCLEASE FROM THE INTESTINAL MUCOSA OF THE RAT
Authors: Lee C. Y. , Zbarsky S. H.
Published: December 2009

A cell-free extract of mucosal scrapings of rat intestine in Krebs–Ringer phosphate buffer was shown to possess high levels of deoxyribonuclease (DNase) activity. Twenty percent saturation of the extract with ammonium sulfate gave a precipitate with enzyme activity towards DNA which resembled DNase I. Mg++ions were required for its activity which was inhibited by EDTA, citrate, arsenate, and inhibitor from pigeon-crop glands. Both the crude extract and the fraction precipitated by 20% saturation with ammonium sulfate showed optimum activity near pH 6. The crude extract, however, contained some activity which did not require Mg++. Digestion of DNA with either the crude extract or the partially purified enzyme gave rise to products ranging in size from mononucleotides to oligonucleotides of 7 units (or more) which could be separated by chromatography on DEAE-cellulose. Further treatment of the hydrolysates with snake venom or spleen phosphodiesterase and phosphomonoesterase showed that the DNase precipitated by 20% saturation with ammonium sulfate gave oligonucleotides terminating in 5′-phosphate whereas the original crude extract yielded oligonucleotides with both 5′- and 3′-phosphomonoester linkages. It was concluded that the crude extract contained a second endonuclease of the DNase II type.
THE EFFECTS OF PHENYLALANINE ANALOGUES ON THE METABOLISM OF PHENYLALANINE IN RATS
Authors: Godin Claude , Dolan Gail
Published: December 2009

Rats expired14CO2slightly faster when DL-phenylalanine-1-14C rather than DL-phenylalanine-3-14C was injected. An injection of DL-fluorophenylalanine-3-14C produced more radioactive CO2than did phenylalanine-3-14C; DL-beta-thienylalanine-3-14C produced only trace amounts of14CO2but significant levels of radioactivity in the urine. When an excess of one of the nonradioactive phenylalanine analogues was injected at the same time as radioactive phenylalanine, the catabolism of the radioactive amino acid was accelerated. This was shown by an increase in the radioactivity in both the CO2and urine when beta-thienylalanine or 2-amino-3-phenylbutanoic acid was used, and in the urine alone when fluorophenylalanine was used. The incorporation of radioactive phenylalanine into tissue proteins was decreased when one of the nonradioactive phenylalanine analogues was injected simultaneously. However3the incorporation into proteins of tyrosine-14C derived from injected phenylalanine-14C was increased under these conditions.
OBSERVATIONS ON SOME EFFECTS OF THE SODIUM SALTS OF CERTAIN MONOCARBOXYLIC ACIDS ON ESTABLISHED CELL LINES
Authors: Pace Donald M. , Aftonomos Byron Th. , Elliott Alice , Sommer Steven
Published: December 2009

There appears to be very little information in the literature pertaining to concentrations of various air pollutants or tobacco-smoke constituents that may be toxic or nontoxic to tissue cells cultivated in vitro. We have undertaken the task of ascertaining these levels and this report records observations concerning the first few of many known pollutants.The effects of the sodium salts of 10 monocarboxylic acids (formate, acetate, propionate, butyrate, valerate, caproate, oenanthylate, caprylate, caprate, and benzoate) on several established cell lines (HeLa, strain L, human lung, human skin) were studied.All of these compounds at a concentration of 10 mg% were toxic to the cell lines tested with the exceptions of formate, acetate, and benzoate on strain L, and of valerate and caprylate on human lung.All the compounds either stimulated proliferation or had no significant effect at 1 mg% except caproate and benzoate, which were toxic to human lung and human skin cells, respectively.
PROPERTIES OF THE PHOSPHOLIPASE B FROM PENICILLIUM NOTATUM
Authors: Beare Joyce L. , Kates Morris
Published: December 2009

Phospholipase B from Penicillium notatum catalyzed rapid deacylation of purified egg lecithin, in the absence of any activators, when the substrate was ultrasonically dispersed. The rate of enzymic hydrolysis depended on the degree of dispersion of the substrate and also on its degree of unsaturation. Decrease in acyl ester groups was accompanied by release of water-soluble phosphate identified as glycerylphosphorylcholine; no lysolecithin was detected by thin-layer chromatography at any stage of the reaction. The optimum pH in acetate buffer was 4.0, and the apparent Kmwas 6.3 mM for the ultrasonically dispersed substrate. The enzyme attacked lysolecithin more rapidly than lecithin. Enzymic activity was not affected by iodoacetate, cyanide, or cystine, but was strongly inhibited by glutathione, cysteine, thioglycollate, ferrous and ferric ions, or by prolonged dialysis. Inhibition by glutathione was completely reversed by ferricyanide. These results suggest that the enzyme requires —S—S— linkages for activity.
METABOLISM OF AMINO ACIDS IN AGROBACTERIUM TUMEFACIENS: II. UPTAKE OFL-VALINE BY GROWING CELLS
Authors: Behki R. M. , Hochster R. M.
Published: December 2009

Growing cells of Agrobacterium tumefaciens strain IIBV7K (tumorogenic) metabolized14C-valine following its rapid uptake from the medium and released a non-amino metabolite (α-ketoisovaleric acid) into the extracellular fluid. This metabolite was taken up subsequently when the external valine concentration became limiting and was incorporated into protein, probably after conversion to an amino acid, α-Ketoisovaleric acid was not taken up when protein synthesis was blocked, e.g. by chloramphenicol, suggestive of an inducible entry system.α-Ketoisovaleric acid itself inhibited the uptake of14C-valine. It also suppressed the incorporation of label into protein by competition. Hydroxylamine inhibited the incorporation of14C-valine into protein without affecting valine entry into the cells. Glycine inhibited uptake as well as incorporation. Initially, glutamate inhibited14C-valine uptake and incorporation strongly; this was followed after 10 minutes, by rapid and linear entry and incorporation rates of the radioactive substrate.The results are discussed and compared with those from resting cells of A. tumefaciens, details of which were published in a previous paper.
CALENDIC ACID IN SEED OILS OF THE GENUS CALENDULA
Authors: Chisholm Mary J. , Hopkins C. Y.
Published: December 2009

Seed oils of 17 definite and putative species of Calendula were examined. The major fatty acid of C. arvensis oil was identified as trans-8, trans-10, cis-12-octadecatrienoic acid (calendic acid). Spectrometric evidence demonstrated that all 17 species contained the same acid, in amounts varying from 38.9 to 58.4% of the oil.Seed was collected at intervals during maturation from growing plants of C. officinalis. Analysis of the seed and the oil showed that the conjugated trienoic acid was present at an early stage of development and increased steadily in amount to maturity. Accumulation of hydroxydienoic or conjugated dienoic acid in quantity was not observed at any stage although small amounts may have been present. It is concluded that calendic acid is formed in the seed by a rapid continuous process.
A NON-NUCLEOTIDE POLYMER FOUND IN THE DNA OF THE SAND DOLLAR, ECHINARACHNIUS PARMA: II. PRELIMINARY CHARACTERIZATION
Authors: Rosenkranz Herbert S.
Published: December 2009

A preliminary characterization of the non-nucleotidic component present in the DNA of Echinarachnius parma was undertaken. This material has an extremely high sedimentation coefficient (907 S). It contains no deoxyribose and presumably no ribose. After acid hydrolysis it was strongly ninhydrin-positive and also gave positive tests for reducing sugars as well as a slightly positive test for amino sugars. Upon electrophoretic analysis of an acid hydrolysate, three ninhydrinpositive spots were detected. One of these migrated to the negative electrode with a mobility identical with that of galactosamine, the other migrated to the positive electrode, and the third was neutral at pH 6.3. The spot with a mobility identical with that of galactosamine also gave a positive test for amino sugar. The material was not attacked by α-amylase. However, digestion with a crude trypsin preparation resulted in loss of the banding property in gradients of cesium chloride. Exposure to purified trypsin did not completely digest it, but caused an increase in buoyant density.
STUDIES ON SOME OF THE ENZYMES OF CARBOHYDRATE METABOLISM AND THE CHEMICAL COMPOSITION OF HEN TIBIA
Authors: Chokshi H. R. , Ramakrishnan C. V.
Published: December 2009

Periosteum, cartilage, epiphyseal head, cortical shaft, and marrow of the tibia of White Leghorn hen were studied for chemical composition with regard to calcium, phosphorus, nitrogen, hexosanaine, and moisture, and the cartilage, epiphyseal head, and cortical shaft were also analyzed for citric acid content. In cortical shaft, cartilage, and epiphyseal head the calcium, phosphorus, and hexosamine contents were higher and the nitrogen was lower than in periosteum and marrow. The former parts also showed a greater degree of calcification as judged by Ca:P and Ca:N ratios. Studies were made on the distribution of key enzymes of glycolysis, of the tricarboxylic acid cycle, the hexose monophosphate shunt, and of certain other enzymes in those parts of the tibia that were studied. These enzymes were α-glucan phosphorylase, lactate dehydrogenase, citrate synthase, aconitate hydratase, isocitrate dehydrogenase (NADP), glucose-6-phosphate dehydrogenase, fumarate hydratase, glutamine synthetase, hexosamine synthetase, and L-aspartate: 2-oxogiutarate aminotransferase.The activity of lactate dehydrogenase was found to be much higher than that of the other enzymes in all the regions studied, which strengthens the hypothesis of a greater degree of glycolysis in bone.The activities of aconitate hydratase, isocitrate dehydrogenase (NADP), fumarate hydratase, and lactate dehydrogenase were lower in cortical shaft than in other regions of the bone. Glutamine synthetase was found in marrow but not in the other parts studied. In general, the marrow was found to be enzymically more active than the other regions.