bluuebunny/crossref_metadata_2025 huggingface dataset:
EFFECT OF NEONATAL INJECTION OF CHICKEN ERYTHROCYTES ON NATURAL HETERO-HEMAGGLUTININ TITER IN MICE
Authors: Ashford D. R. , Fairfield F. M. , Bain G. O.
Published: December 2009

Intravenous injection of mice within 6 hours of their birth with chicken erythrocytes resulted in depression of the titer of naturally occurring heteroagglutinins for chicken red cells. By the time the mice were 16 weeks of age, the titer had risen significantly but had not attained control levels. Subsequent challenge by multiple intraperitoneal injections of chicken red cells revealed that impairment of serological responsiveness to this antigen was still present. These observations suggest a close relationship between naturally occurring and immune antigen–antibody systems.
THE OCCURRENCE AND DISTRIBUTION OF FREE ALKALOID SOLANIDINE IN NETTED GEM POTATOES
Authors: Zitnak A.
Published: December 2009

Free alkaloid solanidine was detected in concentrations up to 200 p.p.m. or 33% of the total glycoalkaloid level in bitter Netted Gem potatoes. Dormant tubers of this variety are readily induced to a rapid glycoalkaloid synthesis by exposure to intense solar radiation and near-freezing temperatures, conditions frequently encountered during the potato harvest in northern areas. Under such conditions solanidine is rapidly produced in excess of amounts that could be bound as solanine, the formation of which would likely be limited by the availability of the glycosidic sugar components. The glycosidic binding of the initially synthesized solanidine proceeds at a very slow rate during the subsequent tuber rest period. Distribution studies revealed that the potato peels, representing about one seventh of the whole tuber weight, contained solanine and solanidine, respectively, at concentrations 2.5 and 6.2 times higher than the remaining tuber tissue, or approximately 30% of the total glycoalkaloid amount.The occurrence of the free alkaloid solanidine at certain times in potato tubers of the Netted Gem variety demands a serious reconsideration of any toxicity studies which have been based on the sole use of crystalline solanine, and which have disregarded the possible existence of the free alkaloid in tuber tissues.
PILOCARPINE-INDUCED CONVULSIONS AND DELAYED PSYCHOTIC-LIKE REACTION
Authors: Boyd Eldon M. , Fulford Robert A.
Published: December 2009

The subcutaneous injection into albino rats of pilocarpine hydrochloride at doses in the range of the median lethal dose produced two types of acute toxicity syndromes, an immediate muscarinic convulsive reaction and a delayed psychotic-like reaction. The LD50±S.E. of the immediate reaction was estimated at 642 ± 90 mg per kg and that of the delayed reaction at 430 ± 126 mg per kg. The mean ± standard deviation time to death in the immediate reaction was 34 ± 20 minutes and in the delayed reaction 4.4 ± 2.5 days. The cause of death in the immediate reaction was postconvulsive respiratory paralysis following marked muscarinic activity and accompanied by hypothermia and by vascular congestion of the brain, heart, lungs, and kidneys. The muscarinic and convulsive signs disappeared in survivors by the second day and were replaced by either a depressant or excitant type of neuropsychosis characterized by disorientation and cataleptiform trances. Animals with the depressant type tended to die in hypothermic stupor with capillary vasodilatation and (or) hemorrhage and (or) other toxemic changes in many organs. Animals with the excitant type of reaction tended to survive with degrees of psychotic-like behavior persisting for a month.
THE ESTIMATION OF FIBROUS CONNECTIVE TISSUE IN LIVER BY A CHEMICAL METHOD
Authors: Menon K. K. Govind , Lucas C. C. , Casselman W. G. B.
Published: December 2009

The chemical determination of hydroxyproline has been studied and a modification of the method of Neuman and Logan has been applied to hepatic tissue. The content of hydroxyproline in the livers of rats that had been fed experimental diets has been found to correlate well with the amounts of fibrous connective tissue (structural reticulin plus newly formed collagen) as estimated histologically.
MINOR PROTEINS IN HUMAN ERYTHROCYTES
Authors: Chandrasekhar N.
Published: December 2009

A study of 200 normal human blood samples, by the agar electrophoresis method, revealed that human haemolyzates contain two minor proteins in addition to the normal adult haemoglobin. The two minor proteins appearing in very low concentrations are non-haemoglobin in character, give a negative reaction to benzidine test, but a positive reaction to amido-schwarz. These two proteins have an electrophoretic mobility similar to that of γ-globulin of human serum, but appear as sharp distinct bands on the agar plate. The concentration of these non-haemoglobin components bear no correlation to the blood groups of the samples or to the haemoglobin concentration itself, but the components have some electrophoretic characteristics similar to some of the abnormal haemoglobins.
IMMUNOCHEMICAL EVIDENCE FOR A GAMMA GLOBULIN PECULIAR TO CEREBROSPINAL FLUID
Authors: MacPherson Catherine F. C. , Cosgrove James B. R.
Published: December 2009

Two immunologically different gamma globulins were revealed in "normal" cerebrospinal fluid (NCSF) and in multiple sclerosis cerebrospinal fluid (MSCSF) by immunoelectrophoretic analyses, which employed rabbit antisera prepared against NCSF and MSCSF. Since only one gamma-globulin arc was formed on immunoelectrophoretic analyses of normal human sera (NHS) with rabbit anti-CSF sera and repeated absorptions of anti-CSF sera with human serum failed to remove antibodies to the minor gamma globulin, it would appear that the minor gamma globulin is peculiar to CSF. The major gamma globulin of CSF was shown to be immunologically identical with the single gamma globulin of serum as judged by the fusion of their respective precipitin arcs. The major and minor gamma globulins of NCSF could not be distinguished from those of MSCSF by any of the rabbit antisera used. However, the ends of the precipitin arc formed by the major gamma globulin of NCSF with its homologous antibody became frayed and sometimes doubled indicating it to be immunologically less homogeneous than the gamma globulin of serum. The two gamma globulins of MSCSF and the minor gamma globulin of NCSF migrated more slowly than the major gamma globulin of NCSF. In comparison with NHS, the immunoelectrophoretic patterns of CSF developed with anti-CSF sera were characterized, in the alpha-2 zone, by a greater number of stronger arcs. Experiments on absorbed anti-CSF sera indicated that this was due to differences in the relative concentrations of the various components of this zone in the two fluids.
BLOOD AMINO ACID STUDIES: I. A MIGROMETHOD FOR THE ESTIMATION OF FREE LYSINE, METHIONINE, AND THREONINE
Authors: McLaughlan J. M. , Noel F. , Morrison A. B. , Campbell J. A.
Published: December 2009

By a modification of conventional methods of microbiological assay it was possible to determine the free lysine, methionine, and threonine in 0.2 ml of rat plasma. The small amounts of lactic acid produced in the microassay were estimated photometrically by measurement of the color change of bromthymol blue. Repeated analysis of samples on different days indicated no significant effect of days and the confidence limits for the assays were approximately ± 6% (p = 0.05). Mixtures of foods containing bread and various supplementary proteins were fed to young male rats for 24 hours and then plasma free lysine and methionine were measured. There was a direct relation between plasma free lysine levels and the lysine content of the diet. The method permits the accurate estimation of amino acids in blood of individual rats or in small samples of human plasma.
BLOOD AMINO ACID STUDIES: II. EFFECTS OF DIETARY LYSINE CONCENTRATION, SEX, AND GROWTH RATE ON PLASMA FREE LYSINE AND THREONINE LEVELS IN THE RAT
Authors: Morrison A. B. , Middleton E. J. , McLaughlan J. M.
Published: December 2009

Plasma free lysine levels of growing female rats given a lysine-deficient diet supplemented with graded amounts of lysine were higher than those of males. In both sexes, plasma free lysine values rose rapidly in response to added dietary lysine, and reached a maximum at a dietary lysine concentration of approximately 1.0%. This amount of dietary lysine was about 0.2% greater than that found necessary for maximum growth. Male rats given diets containing rapeseed oil and graded amounts of lysine showed reduced growth and lower plasma lysine and threonine levels as compared to animals given similar diets containing corn oil, but the amount of dietary lysine required for maximum plasma lysine levels was not influenced by the growth rate. Plasma free threonine levels showed a reciprocal relationship with those for lysine. It was concluded that measurement of the ratio between plasma free lysine and threonine levels may provide a sensitive indication of the adequacy of the dietary lysine content.
THE EFFECT OF DIET, AGE, AND SEX ON CHOLESTEROL METABOLISM IN WHITE LEGHORN CHICKENS
Authors: Wood J. D. , Biely J. , Topliff J. E.
Published: December 2009

The cholesterol metabolism of chickens differed in birds of different age and sex. The normal serum cholesterol levels were higher in females than in males and higher in 1-week-old chicks than in mature birds of the same sex. Laying hens were less susceptible to hypercholesterolemia induced by dietary cholesterol than were mature cockerels or young chicks of either sex. Corn oil tended to increase the degree of hypercholesterolemia in all cholesterol-fed birds except young cockerels. A vitamin-A-rich oil, dogfish liver oil, decreased the rise in serum cholesterol level in cholesterol-fed chicks of both sexes, but in mature birds it produced the opposite effect. The addition of 1% cholesterol to the control diet of hens increased the yolk cholesterol concentration of eggs laid by the birds and this increase in concentration was greatly enhanced if 10% corn oil was also present in the diet.
QUANTITATIVE CHROMATOGRAPHIC METHODS: PART 8. CHROMATOGRAPHIC SYSTEMS OF HIGH RESOLVING POWER FOR NUCLEOTIDES
Authors: Moscarello M. A. , Lane B. G. , Hanes C. S.
Published: December 2009

Two paper chromatographic systems of improved resolving power for nucleotides are described. Both systems are based on buffered miscible solvents, used with chromatographic papers previously impregnated with the same buffers. The potential usefulness of these systems in studies on naturally occurring soluble nucleotides and on degradation products of nucleic acids is illustrated.
STUDIES ON THE IN VITRO ANTITUMOR ACTIVITY OF FATTY ACIDS: IV. THE ESTERS OF ACIDS CLOSELY RELATED TO 10-HYDROXY- 2-DECENOIC ACID FROM ROYAL JELLY AGAINST TRANSPLANTABLE MOUSE LEUKEMIA
Authors: Townsend Gordon F. , Brown William H. , Felauer Ethel E. , Hazlett Barbara
Published: December 2009

Previous studies have shown that whole royal jelly, a fraction from royal jelly (10-hydroxy-2-decenoic acid), and certain closely related dicarboxylic acids, some of which are also found in royal jelly, will inhibit the development of transplantable AKR leukemia when the pH is below 5.6.The ester of 10-hydroxy-2-decenoic acid from royal jelly was found to be just as effective against AKR leukemic cells as the acid itself, with the added advantage that it could be used at neutrality.Through the testing of a series of mono- and di-carboxylic acids, as well as other closely related compounds, the activity has been shown to be associated mainly with 9- and 10-carbon straight chain monocarboxylic acids either saturated or unsaturated. Slight variations in the structure either reduce or destroy the activity.
MECHANISM OF SELECTIVE BLOCKADE OF CYCLOPROPANE–ADRENALINE CARDIAC ARRHYTHMIAS BY DICHLOROISOPROTERENOL
Authors: Sutter Morley C. , Dresel Peter E.
Published: December 2009

We reported previously that in cyclopropane-anesthetized dogs dichloroisoproterenol (DCI) sometimes fails to block adrenaline-induced bigeminal cardiac rhythm although it always prevents ventricular fibrillation. The present experiments demonstrated that in animals in which a large dose of DCI did not increase the adrenaline threshold for bigeminy, previously ineffective mechanical elevation of the blood pressure induced bigeminy. Neither methoxamine nor DCI alone caused bigeminal rhythm, but their combination effectively induced bigeminy of long duration. These results are interpreted to indicate that apparent failure of DCI to block adrenaline-induced bigeminy is not due to inability to antagonize this cardiac action, but is due to a combination of the intrinsic cardiac sympathomimetic activity of DCI with an increase in blood pressure induced by the subsequent injection of adrenaline.
THE EFFECTS OF LEAD AND TIN ORGANOMETALLIC COMPOUNDS ON THE METABOLISM OF RAT BRAIN CORTEX SLICES
Authors: Vardanis A. , Quastel J. H.
Published: December 2009

The effects of tetraethyl lead, tetraethyl tin, triethyl lead, and triethyl tin on the metabolism of rat brain cortex slices have been studied. Tetraethyl lead and tetraethyl tin inhibit the active transport of amino acids into rat brain cortex slices at concentrations and under conditions that show no effect on the glucose metabolism of the slices. Tetraethyl lead and tetraethyl tin inhibit the oxidation of L-glutamate by rat brain slices. This effect can be accounted for on the basis of the inhibitory action of these two substances on the transport of the amino acid into the brain tissue.Tetraethyl lead and tetraethyl tin abolish, at low concentrations, potassium-stimulated brain slice respiration in presence of glucose, having little or no effect on unstimulated brain slice respiration. However, the respiration of rat brain cortex slices previously treated with phospholipase A is highly sensitive to tetraethyl lead.The inhibitory effects of the two tetraethyl compounds show differences from those of their triethyl derivatives indicating that the effects of the former substances are not due to admixture with, or conversion to, the latter substances.The brain slices of rats poisoned with either tetraethyl lead or tetraethyl tin are unable to effect the active transport of amino acids. The appearance of this biochemical abnormality coincides with the manifestation of neuropathological symptoms.The mode of action of tetraethyl lead and of tetraethyl tin on brain metabolism in vitro is discussed. It is suggested that they may act on phospholipid groups concerned with amino acid and cation transport at the cell membrane.
COMPARISON BETWEEN SEASONAL AND THERMAL ACCLIMATION IN WHITE RATS: V. METABOLIC AND CARDIOVASCULAR RESPONSE TO NORADRENALINE
Authors: Héroux O.
Published: December 2009

White rats cold-acclimated at a constant temperature in the laboratory are known to be more sensitive to noradrenaline than warm-acclimated controls. The present study reveals that this responsiveness to noradrenaline is linearly related to the temperature at which the animals are conditioned. Concomitant measurements (after intramuscular injection of noradrenaline) of oxygen consumption, blood pressure, and heart rates on white rats acclimatized to outdoor summer or winter conditions revealed a much greater metabolic and cardiovascular sensitivity to noradrenaline in winter than in summer rats. The slight degree of shivering upon exposure to 6 °C which was observed in the outdoor winter rats, as well as their great sensitivity to noradrenaline, suggests that under both indoor and outdoor environmental conditions, increased cold resistance is obtained through similar metabolic mechanisms.
TRACE ELEMENTS IN TRANSPLANTED TUMORS
Authors: Yip Cecil C. , Shaw Denis M. , Nace Paul F.
Published: December 2009

Spectrographic analyses were made of three transplanted tumors and two normal tissues of mice and hamsters. Significant differences, both qualitative and quantitative, were found among the tumors and between tumor and normal tissue.Boron and molybdenum were characteristic of the melanoma and were undetected or most severely reduced in normal muscle, leukemia, and sarcoma. Chromium was a significant component of the melanoma-host liver, but was not detected in other livers. Nickel was found in the normal liver, but was lacking from the melanoma-host and leukemia-host livers.
THE INFLUENCE OF DIETARY FAT ON THE FATTY ACID COMPOSITION OF LIVER, CARCASS, AND MILK OF RATS
Authors: Beare Joyce L.
Published: December 2009

Fatty acids of liver, carcass, and milk of rats fed corn oil, rapeseed oil, partially hydrogenated herring oil, or margarine were examined by gas–liquid chromatography. Appreciable quantities of linoleic acid were maintained in the tissues and milk, even when the hydrogenated herring oil with a low level of linoleic acid was fed. The proportion of C20and C22acids deposited or secreted was related to that of the diet, and was highest with rapeseed oil. In the livers of rats fed each diet, long-chain, polyunsaturated acids were observed. The fatty acids of milk more closely reflected the dietary pattern than did those of the tissues.
EXCRETION OF 4-AMINO-5-IMIDAZOLECARBOXAMIDE AND CREATINE:CREATININE RATIOS IN HUMAN AND MOUSE MUSCULAR DYSTROPHY
Authors: McGeer E. G. , McGeer P. L. , Miller J. R. , Derry D. , Nichol C.
Published: December 2009

Excretion of creatine, creatinine, and 4-amino-5-imidazolecarboxamide (AIC) was studied in genetically determined muscular dystrophy in the human and mouse. The AIC excretion was normal in both affected humans and mice as compared with groups of comparably aged controls. The creatine-to-creatinine ratio for human muscular dystrophics was more than four times as great as for their unaffected siblings. Both normal and dystrophic mice showed a "creatinuria" as compared to humans. The creatine-to-creatinine ratio for dystrophic mice was significantly higher than the controls, but the difference was apparent only in the first 2 months of life.
EFFECTS OF PHYSICOCHEMICAL AGENTS ON THE ELECTROPHORETIC PROPERTIES OF SERUM PROTEINS IN STARCH GEL MEDIUM
Authors: Richter M. , Gold J. , Rankowicz W. , Rose B.
Published: December 2009

The effects of physical and chemical agents on the electrophoretic properties of the serum proteins have been investigated utilizing both starch gel and paper electrophoresis. It has been found that freezing and thawing do not produce any alterations in the serum proteins whereas heating at either 47 °C or 55 °C causes a certain degree of homogenization of the serum proteins.
RESISTANCE TO 6-MERCAPTOPURINE: II THE SYNTHESIS OF THIOINOSINATE IN A 6-MERCAPTOPURINE-RESISTANT SUBLINE OF THE EHRLICH ASCITES CARCINOMA
Authors: Paterson A. R. P.
Published: December 2009

An assay for the synthesis of thioinosinate by the nucleotide pyrophosphorylase reaction in tissue extracts has been developed and has been applied in a comparison of the Ehrlich ascites carcinoma and a 6-mercaptopurine-resistant subline. Previously, it was shown that intact Ehrlich cells accumulated substantial amounts of thioinosinate in the presence of 6-mercaptopurine, whereas cells of this resistant subline contained only minor amounts of the analogue nucleotide under the same circumstances. In the present study, it was found that extracts of the two cell types had a similar capacity for the pyrophosphorolytic synthesis of thioinosinate. These results have been interpreted to mean that the transport of 6-mercaptopurine across the cell membrane was defective in the resistant subline.
THE FORMATION OF PHOSPHOLIPIDS FROM C14-LABELLED PRECURSORS IN SLICES FROM IMMATURE RAT BRAIN
Authors: Pritchard E. T.
Published: December 2009

The relative incorporation of several C14-labelled compounds into the phospholipid and free cholesterol of developing rat brain slices at various ages from 1 to 19 days was examined. Experiments have shown that labelling of saturated fatty acids of phospholipids and cholesterol from acetate-1-C14and propanoate-1-C14was much more in 1- to 9-day animals than in older animals while the labelling from non-fatty acid precursors such as ethanolamine-1,2-C14and choline-Me-C14was not greatly affected by the aging processes. Palmitic acid was the major acid labelled by acetate, but both stearic and myristic acids received appreciable activity.The results tend to indicate that the saturated fatty acids of rat brain phospholipids are formed rapidly at a very early stage in brain development. The activity of this synthetic system then appears to decrease to the low level apparent in the adult rat. The glycerol–phosphate-base moieties of the phospholipids, on the other hand, appear to retain their relatively high replacement activity at all ages.
COMPOSITION OF EPIPHYSEAL CARTILAGE: III. DIFFERENCES IN ENZYMATIC ACTIVITIES OF EPIPHYSEAL AND ARTICULAR CARTILAGES OF RACHITIC CHICKS
Authors: Cipera J. D. , Willmer J. S.
Published: December 2009

From a comparative study of enzymatic activities in epiphyseal and articular cartilages of 3-week-old rachitic chicks it appears that the activities of pyrophosphatase and adenosine triphosphatase are approximately four times higher in epiphyseal than in articular cartilage. The greater activity of epiphyseal cartilage is even more pronounced in the cases of alkaline phosphatase and hexosamine synthetase. Phosphorylase, on the other hand, is more active in articular cartilage. The significance of these observations is discussed.
BIOCHEMICAL STUDIES OF AN UNNATURAL AND ANTITUMOR AMINO ACID: 1-AMINOCYCLOPENTANECARBOXYLIC ACID: I. TOXICITY AND TISSUE DISTRIBUTION
Authors: Berlinguet L. , Bégin Nicole , Babineau L. M. , Martel F. , Vallée Rita , Laferté R. O.
Published: December 2009

The unnatural amino acid 1-aminocyclopentanecarboxylic acid (ACPC) is toxic to rats when given at concentrations of above 0.1% in the diet, or in successive 50 mg/kg daily intraperitoneal injections. A single injection of 300 mg/kg did not kill any rats. After injection, the concentration of ACPC in the blood of the animals was constantly low and the urinary excretion was also very slow. Using radioactive ACPC, it was found that the substance was widely distributed in the tissues and while it was never incorporated into the proteins, it was always found in the cellular fluid.
INHIBITORY EFFECT OF THIOPENTONE ON THE PYRUVIC DEHYDROGENASE IN BRAIN: REVERSIBILITY OF ACTION BY THIAMINE PYROPHOSPHATE AND LIPOIC ACID
Authors: Fahmy A. R. , Ibrahim H. H. , Talaat M.
Published: December 2009

A study of the effect of Thiopentone sodium on pyruvate oxidation in brain tissue revealed that the action of this drug could be attributed primarily to an inhibition of pyruvic dehydrogenase, the enzyme which degrades pyruvate to the level of acetate. Of the four cofactors needed by the enzyme, thiamine pyrophosphate (TPP) and lipoic acid (Lp) modified the inhibition when added separately. The inhibition was completely relieved when thiamine pyrophosphate and lipoic acid were added together, suggesting that Thiopentone may be competing not with either alone but with a complex of the two such as "lipothiamide pyrophosphate". Alpha-Ketoglutaric dehydrogenase, which requires the same cofactors as pyruvic dehydrogenase, was somewhat less affected by Thiopentone sodium.
LOW-TEMPERATURE ENVIRONMENTAL STRESS AND THE METABOLISM OF VITAMIN A IN THE RAT
Authors: Phillips W. E. J.
Published: December 2009

Carotene and vitamin A metabolism in the rat were studied at two environmental temperatures. The utilization of carotene is greater in animals maintained at a low environmental temperature (2°) than at room temperature (22°). This occurred within a period of 3 days. Both the hepatic storage and the rate of metabolism of orally administered vitamin A were unaffected by environmental temperature. The response of Wistar and Sprague–Dawley strains was similar.
RADIOAUTOGRAPHIC STUDY OF S35O4 UPTAKE BY EPIPHYSEAL CARTILAGE IN EXPERIMENTAL LATHYRISM
Authors: Shintani Yurika K. , Taylor H. E.
Published: December 2009

Disturbances in the uptake of radiosulphate were observed in radioautographs of the epiphysis of rats made lathyritic by giving either beta-aminopropionitrile or semicarbazide. There was a decreased uptake of sulphate which became more marked as the lesions advanced and an increased uptake was noted as the lesions regressed when the rats were returned to a normal diet. In normal rats, the radio-sulphate shifted to the zone of calcifying cartilage by the 4th day postinjection and, by the 7th day, it was concentrated over the ossifying trabeculae. In lathyrism this shift was delayed and the radiosulphate image was still concentrated in the cartilage matrix at days 4 and 7 postinjection. It is believed these findings reflect a disturbance in the matrix acid mucopolysaccharides and an interference with endochondral growth in lathyrism.
HAEMATOLOGIC CHANGES CAUSED BY HYPOTHERMIA IN HAMSTERS AND RATS
Authors: Orme T. , Beaton J. R. , Laufer J.
Published: December 2009

As a consequence of hypothermia (15 °C rectal temperature) in the rat and the hamster, there are increases in red cell fragility and in blood clotting time and a decrease in prothrombin time. In the hypothermic hamster there are significant increases in haemoglobin and erythrocyte count but mean corpuscular volume, mean corpuscular haemoglobin content, and serum protein levels are not altered. These findings indicate that, unlike the hypothermic rat, the hypothermic hamster has an increased haematocrit as a consequence of increased release or decreased destruction of erythrocytes rather than as a consequence of increased cell size and decreased plasma volume. Hypothermia causes a marked leukopenia in both the hamster and the rat but causes an alteration in the relative numbers of lymphocytes and neutrophiles only in the rat.
EFFECTS OF X IRRADIATION ON ENZYME SYNTHESIS DURING LIVER REGENERATION
Authors: Myers D. K.
Published: December 2009

Twenty-four different enzymes or enzyme systems have been assayed in regenerating rat liver from control and irradiated animals at various times after partial hepatectomy. X irradiation, either of the whole liver region or of an exteriorized liver lobule, interfered with the accumulation of only three of these enzymes: deoxycytidylate deaminase, thymidine Phosphorylase, and NAD pyrophosphorylase. Irradiation did not affect the synthesis of related enzymes such as adenosine and guanine deaminases, and inosine and uridine phosphorylases. The effects of irradiation on enzyme synthesis in regenerating liver would appear to be highly selective.
THE INFLUENCE OF IPRONIAZID AND PYROGALLOL ON THE THERMOGENIC EFFECTS OF NORADRENALINE
Authors: Johnson Gordon E. , Sellers E. A.
Published: December 2009

The effects of administering a monoamine oxidase inhibitor (iproniazid) or an inhibitor of catechol-O-methyl transferase (pyrogallol) on the calorigenic response produced by injecting noradrenaline intravenously or subcutaneously to Wistar rats are described. The influence of isoniazid on the calorigenic response to subcutaneously administered noradrenaline was also studied. The effects of syrosingopine and tetrabenazine, with and without inhibitors, and of dl-normetanephrine, were also observed. Inhibition of monoamine oxidase increased and prolonged the calorigenic response to exogenous noradrenaline or to noradrenaline released endogenously. Isoniazid, chemically related to iproniazid but not an inhibitor of monoamine oxidase, or pyrogallol, caused little change in the calorigenic response. Thus oxidative deamination appears to be the primary reaction responsible for the termination of the calorigenic response.
THE EFFECT OF INDUCED HYPOXIA ON OXYGEN UPTAKE DURING MUSCULAR EXERCISE IN NORMAL SUBJECTS
Authors: Cronin R. F. Patrick , MacIntosh Donald J.
Published: December 2009

During the moderate exercise of treadmill walking, steady-state oxygen uptake bears a linear relationship to the work performed (i.e. to the slope of the treadmill), when the speed of walking is kept constant. Four normal male subjects were studied on the treadmill at several levels of exercise while they were breathing air and again while breathing a mixture of approximately 11% oxygen in nitrogen. An alteration in the linear relationship between oxygen uptake and work, established with the subjects breathing air, was observed when the subjects were restudied breathing 11% oxygen. In each case, this alteration indicated that the subject took up less oxygen while breathing a low-oxygen mixture despite the accomplishment of similar work loads. That this phenomenon is explicable on the basis of slower attainment of the steady state was excluded by prolonging each exercise period in two subjects. Another possible explanation, i.e. that the subjects effect greater utilization of anaerobic metabolic sources while hypoxic, was excluded by direct measurement of the oxygen debt after each period of exercise. It is concluded that exercising normal subjects exhibit an adaptive mechanism under conditions of induced hypoxia permitting reduced oxygen uptake for a given work load.
EFFECTS OF ANGIOTENSIN INFUSIONS ON URINARY EXCRETION OF COMPOUND III AND SUBSTANCES OTHER THAN ALDOSTERONE
Authors: Nowaczynski Wojciech , Koiw Erich , Biron Pierre , Chrétien Michel , Genest Jacques
Published: December 2009

Intravenous infusions of synthetic angiotensin II in human volunteers resulted in the increase of the urinary excretion of at least three ultraviolet light absorbing substances referred to as compounds III, IX, and X. This was concomitant with the increase of the urinary aldosterone excretion.Compound III has been partially described before; this is extended. A brief characterization of compounds IX and X is included (see Appendix).
DIRECT PAPER CHROMATOGRAPHY OF SOLUBLE COMPOUNDS IN SMALL SAMPLES OF TISSUE ADHERING TO THE PAPER
Authors: Bidwell R. G. S.
Published: December 2009

A technique is described by which samples of tissue weighing from 1 to 10 mg can be frozen and ground and then stuck to paper chromatograms and the soluble compounds separated by normal solvent development. The advantages and special applications of this technique are discussed.
THE MECHANISM OF PACEMAKER ACCELERATION DUE TO INCREASED INTRA-ATRIAL PRESSURE IN THE ISOLATED ATRIUM
Authors: Mainwood G. W.
Published: December 2009

A closed circuit with a miniature pump was used to perfuse isolated rat atria through the lumen. The rate of spontaneous atrial potentials was measured continuously on a recording potentiometer.The response of the atrium to changes in luminal pressure was observed under a number of different conditions. The acceleration due to increased pressure was greatest when the perfusing fluid contained low bicarbonate concentrations (5–10 mmolar) and was very much reduced or abolished with 28 mmolar bicarbonate. Pacemaker rate at constant pressure varies directly with pH in the presence of high bicarbonate concentrations. The pressure response may be interpreted in terms of a pH gradient across the atrial wall which is dependent on the bicarbonate concentration and may be reduced by stretching the atrium.
CHOLINOLYTICS IN THE TREATMENT OF ANTICHOLINESTERASE POISONING: I. THE EFFECTIVENESS OF CERTAIN CHOLINOLYTICS IN COMBINATION WITH AN OXIME FOR TREATMENT OF SARIN POISONING
Authors: Coleman I. W. , Little P. E. , Bannard R. A. B.
Published: December 2009

The protection to sarin poisoning afforded mice by treatment with N-methylpyridinium-2-aldoxime methanesulphonate (P-2-S) in combination with each of 34 cholinolytic compounds used as substitutes for atropine sulphate has been assessed. Twenty-two of the drugs examined in the mouse at a dosage of 50 μmoles/kg gave protection equal to or greater than that afforded by atropine sulphate. The most potent drug was 4′-N-methylpiperidyl 1-phenylcyclopen-tanecarboxylate hydrochloride (G-3063), which was 2.3-fold as effective as atropine sulphate.l-2′-Diethylaminoethyl α-cyclohexyl-α-2″-thienyl glycolate d-bitartrate (Win 5779-6),2′ -diethylaminoethyl 1-phenylcyclopentanecarboxylate hydrochloride (Parpanit), and l-tropyl α-methyltropate hydrochloride were 1.8-, 1.5-, and 1.4-fold as effective, respectively. Eighteen of the compounds were examined in the rat, with 11 showing potency equal to or greater than that shown by atropine sulphate. In this species the most potent drugs were G-3063, which had 4.0 times the activity of atropine sulphate, Win 5779–6 (4.8-fold), and atropine methanesulphonate, followed by 1-cyclohexyl-1-(2′-thienyl)-3-(1″-piperidyl)-propanol-1 hydrochloride (Win 12085) and Parpanit.
FURTHER STUDIES ON SWELLING OF BRAIN SLICES
Authors: Pappius Hanna M. , Klatzo Igor , Elliott K. A. C.
Published: December 2009

The fluid in incubated brain tissue slices which is permeable by inulin from the surrounding medium, the "inulin space", consists mostly of fluid taken up in swelling but also of a little of the initial water. Unless the tissue is kept cold until aerobic conditions have been fully established, some fluid is taken up which is not penetrated by inulin and is therefore intracellular. Inulin and sucrose, previously absorbed by slices incubated aerobically in their presence, diffuse quickly from slices when these are placed in inulin-free or sucrose-free medium. This indicates that pinocytosis is not involved in the uptake of swelling fluid by incubated slices. When protein labelled with a fluorescent dye is present in the incubation medium, its distribution in the water of tissue slices is similar to that of inulin. This makes possible microscopic visualization of the water compartment in question. Freezedried preparations of slices of grey or white matter that had been incubated with labelled protein revealed under the fluorescent microscope an area of intense fluorescence in the margins. This indicates that the protein space and, by inference, the inulin space represent a damaged region of the slice and are not a measure of definite extracellular or intracellular compartments. This finding is in agreement with the electron-microscopic evidence for the absence of extensive extracellular space in brain. However, the demonstration that the uptake of the greater part of the swelling fluid is in damaged peripheral areas of the slice is in disagreement with conclusions, drawn from electron-microscopic observations, that swelling occurs exclusively in glial cells. Swollen glial cells may account for a small but significant intracellular swelling in incubated slices. Present studies on effects of fixation of cerebral cortex slices indicate that the swelling which we observe by weighing unfixed tissue should also be observable by electron microscopy.
ENZYMATIC AND METABOLIC ADAPTATIONS: II. CHANGES IN ADRENALECTOMIZED RATS SUBJECTED TO DIETARY MODIFICATIONS
Authors: Willmer J. S. , Foster T. S.
Published: December 2009

Changes in the activity of five liver enzymes in adrenalectomized rats were observed during adaptation to three experimental diets. Considerable differences were observed between these results and those obtained from intact rats, some of the changes being attributable to limitations of caloric intake. Differences between adrenalectomized and unoperated animals were also demonstrated in the rates of oxidation of glucose-1-C14and glucose-6-C14.Partial restoration of normal adaptive enzyme patterns was accomplished by treatment with individual adrenal cortical steroids. Hydrocortisone was found to be the most effective steroid used in this respect.
THE INCORPORATION OF p-FLUOROPHENYLALANINE INTO TOBACCO MOSAIC VIRUS
Authors: Townsley P. M.
Published: December 2009

Disks of diseased tobacco leaf tissue were treated with phenylalanine and with the analogue p-fluorophenylalanine. The expressed sap was separated into its components by agar gel zone electrophoresis. p-Fluorophenylalanine was shown to be incorporated into TMV at a reduced rate as compared with the natural amino acid phenylalanine. The analogue inhibited incorporation of phosphorus, a reversal probably due to the increase in phenylalanine observed in the soluble amino-acid-free fraction.
A STUDY OF A WATER-SOLUBLE COMPLEX OF PRODIGIOSIN PRODUCED BY A STRAIN OF SERRATIA MARCESCENS
Authors: Yoshida Seiichi
Published: December 2009

A water-soluble pigment excreted from Serratia marcescens has been purified by precipitation with ammonium sulphate, dialysis, and ultracentrifugation at different pH values. The purified pigment showed a single band in the ultracentrifuge and by electrophoretic analysis at several pH values. An average molecular weight of 5 × 106 was calculated from light-scattering measurements. This pigment is composed of carbohydrate and protein combined with prodigiosin, and several properties of the complex are described.
THE EFFECT OF DIETARY LIPIDS ON THE SERUM CHOLESTEROL OF RATS
Authors: Wilkens J. A. , Wit H. de
Published: December 2009

Experimental conditions were devised under which the effect of dietary triglyceride oils on the serum cholesterol concentration of rats resembled the effect of these oils on man. No artificial additives were used in the diet. By the use of this technique, the hypocholesterolemic activity of sunflower seed oil was studied. The feeding of fractions prepared by chemical and physical means showed that the unsaponifiable matter was responsible for a substantial part of the hypocholesterolemic action of the unmodified oil. Several fractions with similar fatty acid compositions were prepared which had different effects on the serum cholesterol level. Some known compounds of the unsaponifiable matter were next fed, dissolved in coconut oil. β-Sitosterol and squalene had little effect but a combination of these with α-tocopherol and β-carotene produced a significant depressing effect. The administration of cholesterol with a fat-free diet did not raise the serum cholesterol level unless the sterol was given dissolved in oil. Increasing quantities of sterol of up to 6%, dissolved in oil, produced increasing serum levels. Larger quantities caused no further rise. The possibility that only dissolved cholesterol is absorbed is discussed.
A PROPOSED MECHANISM FOR THE EFFECT OF DIFFERENT DIETARY FATS ON SOME ASPECTS OF CHOLESTEROL METABOLISM
Authors: Wilkens J. A. , Wit H. de , Bronte-Stewart B.
Published: December 2009

To explain the effect of dietary cholesterol and different fats on serum cholesterol concentration a hypothesis is proposed according to which the condition for the absorption of dietary cholesterol is its state of solution in dietary or endogenous fats. Dietary fats, free from cholesterol, exert their effect on serum cholesterol concentration by causing reabsorption of biliary or endogenous cholesterol. To test this hypothesis the solubility of cholesterol in a number of natural and modified triglyceride fats at 37 °C was determined and found to correlate with the effects of these fats on the serum cholesterol concentration of rats and man. Relatively high solubilities were associated with high serum levels and vice versa. Artificial modification of both unsaponifiable matter and fatty acids of triglyceride oils was found to alter the solubility of cholesterol in these oils. The solubility concept is discussed as a possible mechanism underlying the effect of different dietary fats on serum cholesterol concentration and other aspects of cholesterol metabolism such as absorption, excretion, and liver synthesis.
CATECHOLAMINE CONTENT OF SPINAL CORD
Authors: McGeer E. G. , McGeer P. L.
Published: December 2009

Values for the catecholamine content of spinal cords of rats, rabbits, cats, humans, hogs, and oxen were obtained. The catecholamine content tended to decrease with increasing size of the species. Dopamine averaged 1.0 micrograms/g of wet tissue in the rat, and 0.2 micrograms/g in the ox; noradrenaline averaged 0.15 micrograms/g in the rat, and 0.10 micrograms/g in the ox. Adrenaline could not be detected with certainty. The catecholamine content of gray matter was much greater than that of white and seemed greater in the posterior than in the anterior part of cord. No segmental distribution was apparent. Dopamine and noradrenaline were both found in the free and bound state. Modifications to previous methods of catecholamine determinations are described. Recoveries in the analyses were determined by using radioactive tracers in preference to the usual method of doing parallel analyses. No deterioration in catecholamine content of tissues was apparent for the first 3 hours after death, but thereafter deterioration was evident.
RELATIONSHIPS BETWEEN STRUCTURE AND ACTIVITY OF MALEIC HYDRAZIDE ANALOGUES AND RELATED COMPOUNDS
Authors: Parups E. V. , Hoffman I. , Morley H. V.
Published: December 2009

The growth inhibiting activities of a number of compounds structurally related to maleic hydrazide have been examined using the technique of bud growth inhibition. The degree of inhibitory activity of maleic hydrazide derivatives depended on the ease with which the plant can split off substituents. Straight-chain compounds which partially resemble maleic hydrazide were not as active as the parent compound and ring closure was necessary for full activity. Residue data for some of the tested compounds showed that activity failure was not due to lack of uptake and translocation. The analytical procedure for maleic hydrazide is shown to be valid for the quantitative determination of N-hydroxymethyl-MH and N-benzoyl-MH.
A COMPARISON OF METHODS FOR THE ISOLATION OF DEOXYRIBONUCLEIC ACID FROM SMALL AMOUNTS OF RAT TISSUE
Authors: Mezei C. , Zbarsky S. H.
Published: December 2009

Different procedures were studied for the isolation of deoxyribonucleic acid from liver and intestinal mucosa of the rat. The DNA preparations were compared with respect to intrinsic viscosities, extinction coefficients, nitrogen and phosphorus content, and base ratios. Hydrolyzates of the DNA samples contained amino acids indicating the presence of protein or peptides in the preparations. An improved technique was developed for the elution of purines and pyrimidines from paper chromatograms.
LIPID COMPOSITION OF MESOPHILIC AND PSYCHROPHILIC YEASTS (CANDIDA SPECIES) AS INFLUENCED BY ENVIRONMENTAL TEMPERATURE
Authors: Kates M. , Baxter R. M.
Published: December 2009

The lipids of three psychrophilic yeasts of the genus Candida, grown at 10°, were compared with those of a mesophilic yeast (Candida lipolytica) grown at 25° and at 10°. All the yeasts examined had similar contents of total lipids and of phosphatides, and similar phosphatide and neutral lipid compositions. However, the total fatty acids of the psychrophiles and of the mesophile grown at 10° had much higher proportions of linoleic acid and lower proportions of oleic acid than those of the mesophilic yeast grown at 25°; the psychrophilic yeasts also contained linolenic acid, not detected in the mesophilic yeast. The fatty acid composition of the psychrophilic yeast remained fairly constant during its growth cycle, but that of the mesophilic yeast at 10° showed marked changes in the proportions of oleic and linoleic acids in the early stages of growth; similar changes occurred in the mesophile grown at 25°, but at much faster rates. On the basis of these observations and others it is concluded that in the early stages of growth of the mesophile at 25° and 10°, oleic acid is converted rapidly to linoleic, which is then oxidatively metabolized during the later stages of active growth. The higher proportions of linoleic acid in the mesophile grown at 10° could be accounted for by a slower rate of metabolism of linoleic acid during the later stages of growth at the lower temperature.
THE STRUCTURE AND FUNCTION OF CELL MEMBRANES
Authors: Burgen A. S. V.
Published: December 2009

Permeation through cell membranes may occur through solution in membrane lipid, association with carrier molecules, formation of molecular dimers, passage through organized channels or through membrane translocation. It is probable that the predominant mechanism differs according to the type of cell.
LIPID–PROTEIN COMPLEXES IN MEMBRANES OF NERVOUS TISSUE
Authors: Wolfe L. S.
Published: December 2009

Recent investigations have demonstrated that cellular and intracellular membranes within the nervous system contain complex associations of lipids, proteins, and carbohydrates. The myelin sheath contains such complexes derived from the Schwann cell or satellite cell membranes. Similar complexes are found in membranes from grey matter together with less familiar associations between lipids and carbohydrates. Gangliosides are a group of acidic glycolipids which contain among other sugars the sialic acid, N-acetylneuraminic acid. The present state of knowledge on the chemical structure, metabolism, and functional importance of these complex macromolecules is discussed.
THE ROLE OF LONG-RANGE FORCES IN THE COHESION OF LIPOPROTEINS
Authors: Salem L.
Published: December 2009

The various long-range forces which are effective between molecules in their electronic ground states are examined. Orders of magnitude are given for those forces which should occur in the interaction of lipide and protein chains. It is found that electrostatic forces should be responsible for bringing and holding together protein and lipide components, but London – Van der Waals dispersion forces are probably of paramount importance in maintaining the lipide chains together in micelles or double layers.Special attention is drawn to the dispersion forces and to the conditions under which these forces are locally additive; one can calculate accurate values of the dispersion energy of interaction between saturated hydrocarbon chains at short distances (a few angstroms apart) by adding all the bond–bond interactions. A general expression is given for the dispersion energy between two parallel and opposed chains built out of identical units, and numerical values are given for the case of closely packed hydrocarbon chains.The total attraction energy is extremely sensitive to the intermolecular distance. The role of this "distance-specificity" in interactions involving unsaturated fatty acid chains and its contribution to the stability of lipoproteins is briefly examined.
A NOTE ON METABOLIC EFFECTS OF SUSTAINED HYPOTHERMIA IN RATS
Authors: Haynes J. W. , Maur J. M.
Published: December 2009

Hypothermia was induced in non-fasted, female rats by placing animals in individual, cylindrical screen cages under crushed ice until a rectal temperature of 15 °C was attained. No anaesthetic or artificial ventilation was provided. Hypothermic animals were sacrificed after 0, 30, and 60 minutes' maintenance at this rectal temperature and metabolites were measured in blood and liver. It was observed that, as previously reported, hypothermia caused increases in blood packed cell volume, glucose and lactic acid levels, and plasma levels of inorganic phosphorus and total ketones. Maintenance of hypothermia for 30 or 60 minutes either caused no further change or accentuated the changes observed initially in these metabolites. Liver glycogen level decreased significantly after 30 minutes but returned to an almost normal level at 60 minutes. From these observations it is concluded that attainment of a "steady state" condition of hypothermia in non-fasted rats does not alter the pattern of metabolic changes observed in acute hypothermia of short duration.
A NON-SPECIFIC DEPRESSANT EFFECT ON THE IMMUNOLOGICAL RESPONSE
Authors: Bruce Robert , Cinader Bernhard , Percy John
Published: December 2009

The antibody response of mice to intraperitoneally injected sheep red cells was found to be markedly depressed by the injection of isogenic mouse red cells (1,2) given 1–3 days before the antigen. If the isogenic cells were administered at the same time or 1 day after the antigen, the antibody response was not affected. Other non-antigenic substances such as a 5% solution of amino acids exercised a similar depressant effect. The depression of the antibody response did not occur when the isogenic red cells were given intraperitoneally and the antigen by another route. When the effect of specific cells or agents on the antibody response is to be examined it is frequently necessary to make two injections. Only one of the two should be made by the intraperitoneal route.