Experimental Biology and Medicine

Netropsin, an antibiotic from culture nitrates of Streptomyces netropsis, has marked therapeutic effect on experimental vaccinial infections (WR strain) in intracerebrally inoculated mice. It is ineffective against infections in mice with the viruses of feline pneumonitis, influenza, Western equine encephalomyelitis, and poliomyelitis.

Both restrained and unrestrained mice were exposed to cold. The unrestrained animals experienced a small drop in body temperature as compared to the restrained animals whose body temperatures dropped to the death point (approx. 10°C) in about one hour. Anesthetized and dead mice demonstrated greater temperature drops than were found in conscious restrained mice. Conditioning by maintaining the animals one hour per day in restraining cages resulted in a lesser temperature drop on exposure to cold as well as greatly decreased mortality. It was concluded that emotional hypothermia, not resulting from restricted breathing, can be produced in mice by the stress of confinement.

Whole body x-irradiation of mice, rats, and rabbits at the LD₅₀ range increases the activity of certain tissue cathepsins. Liver, kidney, and intestine were the tissues tested, and it was found that one of 3 liver cathepsins, 2 of the same 3 cathepsins in kidney, and 2 of the 3 in intestine were increased in activity by the radiation. This appears due, at least in the case of rat kidney carboxypeptidase, to the destruction by the x-rays of an enzyme inhibitor. It is possible that the source of all inhibitor found in tissues and blood alike is the blood cell, probably the leukocyte. The possibility is suggested that the reduction of carboxypeptidase inhibitor in blood cells may serve as a basis for determining, within 24 hours of the exposure, whether or not an individual has received a lethal dose of ionizing radiation.

Evidence is presented that the enzyme carboxypeptidase is more widely distributed throughout mammalian tissues than is commonly realized. The reasons for previous failure to detect the enzyme are: a) the existence of a natural cellular inhibitor, the effect of which is to mask the enzymatic activity, and b) the fact that two carboxypeptidases probably co-exist in many tissues; the pH optima of these two are different, and one is activated, the other inhibited, by cysteine. The natural cellular inhibitor affects only one of the carboxypeptidases, and does so in a non-competitive fashion.

Twenty-four mice of the Marsh-Albino strain were injected daily for a period of 3 months with desoxycorticosterone acetate (0.2 mg/0.1 cc) in sesame oil. Of these, 1 was killed 3 months after termination of treatment but showed no evidence of tumor, while 9 others, killed 6 months after termination of treatments had subcutaneous tumors of two histological types, fibrosarcoma and myosarcoma. The remaining 10 mice are still alive; all show gross evidence of tumor formation, which became evident 6 months after completion of treatment.

Pure cultures of E. coli and A. aerogenes were grown, lyophilized, and fed to chicks as dietary supplements both in the presence and in the absence of procaine penicillin G. Little or no chick growth response was obtained when either of these organisms were added to the ration in the absence of the antibiotic. Greater gains were obtained when 10 ppm procaine penicillin G were fed. When viable cultures of A. aerogenes and E. coli were fed in combination with penicillin, growth was further increased significantly. The effectiveness of the antibiotic in promoting chick growth was increased 64 and 80% when these organisms were added to the feed. The results obtained illustrate the influence of bacterial environment on the antibiotic growth effect and in nutritional studies.

Previous studies on experimental rat caries suggested the possibility of a relation between heat-processed cereal foods and dental caries etiology. Continuing this type of study, the cariogenic role of heat-processed skim milk powders, has been investigated. Diets containing 35% of commercial skim milk powders prepared by the usual spray and roller processing and also given a subsequent heat-treatment prior to feeding, have been identified with the production of a specific type of surface caries in white rats. The extent and severity of the caries was significantly and consistently increased by heat-treatment of these commercial skim milk powders. The results suggest that a cariogenic effect may be produced by heat-treatment of dry skim milk powders. According to present evidence this cariogenic effect has not been identified with the nutritive growth failures usually associated with heat or storage deterioration of milk proteins.

1. Liver slices were incubated in a physiologic, buffered medium containing cortisone. Following incubation, the steroid fraction was recovered and the individual steroids isolated by paper chromatography. 2. Under the conditions of this experiment, 3 steroids were isolated on the paper chromatogram. The compound of greatest mobility and obtained in largest amount was cortisone, unaltered by incubation. The product of intermediate mobility was identified as Compound F. The least mobile compound was not identified. 3. On the basis of observations in the literature and the experimental data reported here, it is suggested that the metabolic activity of cortisone may actually be dependent on its conversion to Compound

Concentrations of 15 μg/ml or lower of desoxycorticosterone glycoside stimulate growth of chick embryo fibroblasts and decrease the accumulation of cytoplasmic lipids. Concentrations of 30 μg/ml reduce growth and damage the nuclei of the cells.

1. Chick embryos at 8 days of incubation were given one-half or one mg of cortisone acetate by injection onto the chorioallantoic membrane. 2. The one-half mg dose resulted in a reduction of the liver to approximately 86% of the control weight. 3. In the one mg series, the liver was relatively smaller and the eyes and gonads were relatively larger on the basis of 100 g of body weight. In absolute values, the entire embryo and all organs were greatly reduced in size. 4. Measurements of body length, neck, wings and legs after treatment with one mg cortisone indicated the greatest degree of growth inhibition during 8 to 10 days of incubation for all except the legs. 5. A comparison of wet and dry weights from day 10 through day 18 of incubation showed that cortisone-treated embryos retained water. This retention becomes statistically significant at 15 days of incubation.

A fibroma is described as arising from the feather follicle of White Pekin ducks following multiple local applications of methylcholanthrene to the skin.

Attempts have been made to standardize the “surface fixation” test for the diagnosis of brucellosis and at the same time make it a practical rapid and dependable procedure. So far, it has been found to possess remarkable specificity in human brucellosis as judged by comparison with blood cultures. This test may be applicable to the detection of bovine reactors.

1. Though glucose has a slight effect in the process of biosynthesis of ascorbic acid in the germinating mung beans and acetoacetate alone has rather a destructive effect, the product formed by the condensation of the two (2-tetra hydroxy butyl 5-methyl 4-carbethoxy furan) has been found to accelerate the process greatly. 2. Glucose and acetoacetate when added in equimolecular amounts to the germinating beans have also been shown to cause greater biosynthesis of ascorbic acid. 3. The condensation product of glucose and acetoacetate has no inhibitory effect on the loss of ascorbic acid and the probability of this compound, which is also structurally similar to ascorbic acid, acting as a precursor of ascorbic acid has been suggested. 4. Injection of the condensation product of glucose and acetoacetate or of one following the other has been found to raise the ascorbic acid level in the plasma of rats. 5. Glucose has been found to prevent the harmful effect of acetoacetate with respect to depletion of ascorbic acid in vivo. 6. Pathways of glucose metabolism not previously recognized have been suggested.

Addendum. After this paper was communicated for publication, a paper on the origin of 1-ascorbic acid in the albino rats has appeared from the laboratory of King (19), which gives confirmatory evidence of glucose taking part in the biosynthesis of ascorbic acid.

1. Growing male albino rats were fed vit. A ester at levels of 0, 0.75, and 7.5 γ/rat/day. Comparisons were made at these levels of vit. A intake with and without aureomycin added to the diet at the rate of 100 mg/kg. 2. Statistically significant differences were found in weight gains and food intakes between groups receiving different levels of vit. A. 3. Statistically significant differences were not found in weight gains and food intakes between groups receiving antibiotic and their controls at the various levels of intake of vit. A, except on vit. A-free diets. Here weight gains and food intake of the control animals were significantly greater than for animals receiving antibiotics. 4. At a level of intake of vit. A of 7.5 γ/day no significant difference of liver storage was found upon aureomycin supplementation. Kidney storage of aureomycin supplemented animals was significantly less than that of control animals. Under conditions of this experiment at the 7.5 γ /day level of supplementation of vit. A significantly greater storage of vit. A occurred in the liver than in the kidneys. 5. No effect of sparing of vit. A by aureomycin was demonstrated, but on vit. A-free diets aureomycin appeared to enhance the deficiency syndrome.

Biochemical and histochemical methods have demonstrated acid phosphatase activity in the vagina, exo- and endo-cervix, the endometrium, and mucosa of the fallopian tube. The enzyme is similar to that in the human prostate but the activity per mg wet weight is lower.

1. Aureomycin given to chronic alloxan diabetic rats caused an average gain in body weight of 19.0 ± 2.9 g during 28 days. Control chronic alloxan diabetic rats gained 9.6 ± 2.0 g during the same period. 2. During aureomycin administration the animals consumed more food and had increased glycosuria and diuresis.

Sodium-levo-thyroxine in dosage of 0.075 mg, orally, usually reduced radioactive iodine uptake by the thyroid of normal human subjects; this was associated with a rise of protein bound iodine when a dosage of 0.2 mg or more was given. Tri-iodo-thyronine in dosage as low as 0.008 mg orally also reduces the uptake. This is associated with a decrease in serum protein bound iodine.

Intraperitoneal injection of 0.1 γ Piromen/day/mouse for a 5-day period effected a significant increase in the mean survival time of X-irradiated (550 r) mice of the HN Rockefeller Institute strain. Piromen administered with the drinking water at the rate of 0.37 γ /day/mouse for 4 days failed to significantly alter survival time. This may have been due to the small dose actually absorbed. Administration of a larger dose (total dosage, 2.55 γ) after irradiation resulted in fewer survivals than in the untreated controls. The action of Piromen following irradiation appears to be similar to ACTH with respect to survival. The dosage of Piromen is apparently of critical importance.

1. Male rats were raised on a vit. E-deficient diet; some animals were given daily supplements of arginine monohydro-chloride. 2. Arginase activity of liver and kidney determined by the method of Kochak-ian. 3. There was no difference in arginase content of livers and kidneys of animals maintained on a vit. E-supplemented diet, a vit. E-deficient diet and. vit. E-deficient diet containing a supplement of arginine. 4. Administration of arginine did not delay or modify the development of testicular degeneration resulting from vit. E-deficiency.

Adult rats fed the drug DDD rapidly develop signs of some adrenal dysfunction; decreased eosinophil response, decreased uric acid/creatinine ratio, increased insulin sensitivity and decreased response to stress of cold. The urinary and plasma Na and K are not affected.

1. Washed mouse brain mitochondria carried out the complete enzymic conversion of exogenous glucose to carbon dioxide and water. Glucolysis took place an-aerobically and aerobically, with the production of lactic acid. Under aerobic conditions glucose was oxidized by means of a malonate-sensitive cycle. The accumulation of lactic acid was correspondingly decreased. 2. In contrast, the supernatant carried out anaerobic and aerobic glucolysis, but not respiration of glucose. The submicroscopic particle fraction did not carry out the reactions of either system.

Bovine alpha-globulin (bovine plasma fraction IV, Armour) in the presence of guinea pig complement inhibits the growth of the pleuropneumonia-like organisms. Heat-inactivated bovine serum is slightly inhibitory but the alpha-, beta-, and gamma-globulins are non-inhibitory in the absence of complement. Complement by itself does not inhibit growth as extensively as when in the presence of globulin. Alpha-globulin in the presence of the organisms fixes complement in low titer.

1. The PTC factor is concentrated in fractions III and IV-1 of the plasma proteins, Small quantities are found in fractions I and IV-4. None is found in fractions II and V. 2. Since fraction III contains thrombin and fraction IV-1 is poorly soluble, neither is suitable for intravenous administration. 3. The intravenous administration of fraction IV produced marked shortening of the whole blood coagulation time and reduction in residual serum prothrombin in PTC deficiency. The results appear superior to those which can be achieved by the intravenous administration of fraction I in hemophilia.

1. After administration of cholesterol-4-C¹⁴ to rats the main excretory products in the bile are cholic and chenode-soxycholic acid present as taurine conjugates. 2. The labelled material present in feces has been fractionated. It has been found that most of the conjugate has been split. No unchanged cholic acid seems to be left in the feces. A series of different labelled products have been separated some at least of which contain ketonic groups.

Experimental fever in dogs caused by external heating or by injection of a pyrogenic substance resulted in a significant elevation of total serum nonglu-cosamine polysaccharide. An elevation of the polysaccharide content of the pseudo-globulin was noted in all animals, while an elevation of mucoprotein was noted only in the animals subjected to the injections of the pyrogenic substance, pyromen.

1. Intraocular ovarian transplants of gonadectomized rabbits subjected to ECT show follicular stimulation. Twice as many ES treatments were required as EN to obtain growth. Follicles were observed in all stages of development, including both maturing and cystic. Hemorrhagic follicles occurred frequently but terminated in follicular atresia rather than ovulatory corpora lutea. The experimental animals gave good evidence of estrogen production by the ovarian intraocular transplants in the proliferative condition of both the endometrial transplants and the uteri in situ. (No attempt was made to exclude possible adrenal cortical activity.) This was in direct contrast to the lack of activation and even atrophy of transplants (and uteri in situ) in similarly prepared but non-treated controls. 2. It is known that menstruation may be prevented by maintenance of high estrogen levels. This sometimes occurs in the presence of cystic ovarian follicles as well as during continued administration of estrogens. 3. Continued follicular growth with resultant maintenance of high estrogen secretion may result from stimulation of the hypothalamic-pituitary neuro-humeral pathways by the electric current. Such a “constant estrus” condition might account for the interruption of the cyclic activity in women receiving ECT, as well as its resumption as treatments are spaced farther apart.

A group of castrated male albino mice and an uncastrated control group were equally infected with Schistosoma mansoni. Nine weeks later the animals were sacrificed and the adult parasites collected, separated according to sex and counted. The mean adult parasite count per mouse, for each group, showed a significant reduction in the male schistosomes of the castrated animals. This difference indicates a relationship between male sex hormones and the male parasite.

1. Treatment with somatotropic hormone failed to reduce the mortality of mice exposed to 550 r total body x-radiation, even when it was combined with streptomycin to control the development of post-irradiation infection. 2. The mice which received both drugs maintained body weight, but those which received either drug alone lost weight.

1. Young chicks fed diets containing Gantrisin® (sulfisoxazole) at levels of up to 1% of the diet showed no physical abnormalities, were more uniform and thrifty in weight and appearance than the controls and weighed heavier than the controls at 6 weeks of age. 2. Young chicks fed diets containing .03% of Ro 2-0404 or from .03 to 0.3% of Ro2-O201 were also thriftier in appearance and heavier than the controls and showed no physical abnormalities. Young chicks fed diets containing 1% or 0.3% of sulfamethazine, sulfadiazine, sulfanilamide, sulfaguani-dine or sulfaquinoxaline were markedly retarded in their growth.

1. Ultrafiltrates of plasma and serum from normal and thermally injured rats were utilized in a study of non-protein nitrogen changes following thermal injury. The rats were burned deeply over about 30% of the body surface and the bloods were collected 11-12 hours after injury. 2. Absorption spectra were obtained before and after in vitro ultraviolet irradiation of the sera ultrafiltrates. The changes observed in the spectrum of the sera ultrafiltrate of the injured rats is consistent with a modification qualitative and/or quantitative in the sera amino acids, free and combined, and with the appearance of purine containing compounds. 3. Almost the entire increase in filterable nitrogen in the sera of rats after thermal injury consists of urea and free and combined amino nitrogen in their normal relationships. 4. Measurements of specific amino compounds were carried out by ion exchange chromatographic and colorimetric ninhydrin technics. The results obtained by these methods for the amino acids of plasma ultrafiltrates of normal rats are similar to values obtained by others for rat plasma amino acids using microbiologic technics. 5. In the plasma ultrafiltrate of injured rats, there are increases of some amino acids, particularly tyrosine, phenylalanine, and histidine, while other amino acids are decreased. Quantitatively, the largest part of the increase in amino nitrogen is made up of a forepeak (taurine?) and an amino acid conjugate. 6. The amino acid conjugate includes a large fraction unaffected by hydrolysis and a few of the common amino acids. The composition of the conjugate is similar in normal and injured rats.

The effect of semi-starvation on the propulsive motility of the small intestine of albino rats was studied by Macht's technic. At the end of 40 minutes, the charcoal-mixture traversed 72% of the small intestine of the control animals, and 91% in the semi-starved animals.

It has been demonstrated that the psittacosis (ornithosis) viral agent isolated from a turkey is antigenically specific. The Louisiana human, the egret and the turkey strain have in common an endotoxic component probably responsible for their high virulence for man and for their broad infection spectrum. Epidemiologic experience has proven such strains to be the cause of serious outbreaks of pneumonitis in inhabitants of the Louisiana bayou country (Olson and Larson (5)), in poultry dressers and in laboratory workers. Until other strains isolated from turkeys have been carefully compared with other psittacosis viral agents from southeastern United States it is premature to conclude that turkeys are the sole hosts of ornithosis agents of virulence greater than that of strains found in pigeons, ducks, chickens and even psittacine birds. Finally, there is no urgency to burden the unfortunate classification of the psittacosis-lymphogranuloma venereum group with a new species when the technic of neutralization of viral activity merely suggests a specific serotype.

1. Results of this study point to the critical role of potassium in amino acid utilization following protein depletion. Rats depleted only of protein failed completely, even when offered a complete source of amino acids, if at the same time potassium was withheld. If phosphorus was withheld during the repletion period, the rate of recovery was lessened, but complete failure and deaths did not result as with potassium deprivation. Deprivation of sodium, calcium or magnesium did not appear to have immediate limiting effects on the appetite of protein depleted rats for a complete amino acid source, or on their ability to recover lost weight. 2. Fourteen mg of potassium per rat day appeared to meet the requirement for this element. Addition of 10 mQv of potassium per liter to an intravenous protein hydrolysate appears to supply an effective, safe ratio of potassium to amino acid nitrogen.

1. A factor (plasma thromboplastin) can be absorbed from citrated human plasma which shortens the clotting time of normal oxalated recalcified human plasma and increases the prothrombin utilization of platelet-poor hemophilic and thrombocytopenic plasma. This factor has been eluted and purified. An assay for its activity has been developed. A unit of activity, physicochemical properties and biologic activity have been defined. 2. Plasma thromboplastin can be clearly differentiated from other known coagulation factors on the basis of its properties; its evolution requires one or more platelet and plasma factors and contact with a foreign surface. It probably represents the final product of the first phase of blood coagulation (activation of thromboplastin). Its administration has been proven to correct in vivo the defective prothrombin utilization of thromboplastin-deficiency states.

1. It has been shown in rats that ingestion of oil preliminary to thiopental anesthesia will decrease the anesthesia time by about 50%. 2. A suggested explanation for this action is the production of a hyperlipemia by the oil, with the resultant uptake of the circulating thiopental by the chylomicrons.

The inhibition of lysozyme by heparin is shown by the usual criteria of the Michaelis-Menton formulation to be competitive in type.

The equipment and the procedures have been devised for quantitative complement fixation in volumes of 12 mm³. The technic, reduced to a routine basis, is illustrated in the results obtained in the titration of complement and in the estimation of complement fixed by pneumococcus polysaccharide type VIII and its specific antiserum induced in the rabbit. With the procedures described the reaction can be carried out with antigen and antiserum in amounts of the order of 100-fold less than those required for the volumes usually employed, greatly extending the range for the study of material available only in small quantities.

1. There is no appreciable difference between the particle diameters of the 2 Coxsackie viruses—Strain 1816 (Herpangina) and Strain 4520 (Pleurodynia). The diameter is approximately 37 μx for single particles and about 28 μx for particles measured in rows. 2. The sedimentation constants, estimated indirectly, are 167S for the 1816 strain and 175S for the 4520 strain. For the 1816 strain the visible boundary measurements give 153S in this series of experiments. 3. Attaclay is useful in the procedure for preparing partially purified virus from suspensions of infected mouse muscle. 4. The technic of pseudo-replication from agar blocks has led to electron micrographs showing the virus particles in orderly hexagonal arrays.

A study of the nucleic acid concentrations (DNA and PNA) in the developing and functioning mammary glands of rats is reported. DNA increases in the early part of pregnancy and increases only slightly in the lactating gland. PNA increases throughout pregnancy and continues to increase in the lactating gland reaching a maximum value at 21-22 days of lactation. Following enforced weaning the PNA content of the gland falls rapidly. These findings are discussed in regard to growth and function of the glands.

A method based on the ultraviolet spectrum of salicylaldehyde and salicylic acid is presented for the study of liver aldehyde oxidase. By the use of this method it was observed that aldehyde oxidase is inhibited by epinephrine and other adrenergic amines as well as by adrenergic blocking agents. It was observed that inhibition by the first group of substances is reversible and competitive while inhibition by adrenolytic drugs is irreversible and non-competitive.

The ionization constants of 14 basic dyes belonging to 5 chemical classes, azo, azines, xanthenes, oxazines and thiazines, each containing 2-4 compounds, were determined spectrophotometrically in buffered 50% alcoholic solutions. The dyes were those which Ingraham and Visscher have found to be secreted by the stomach. Fairly good agreement for the ionization constants by 3 different methods (spectrophotometric in buffered 50% alcohol, titration in water and in 50% unbuffered alcohol) is obtained for Nile Blue A, Bismarck Brown Y, Rhodamine B, Chrysoidin Y, Neutral Red and Pyronine B. With the exception of Acridine Red these are all the weaker bases. Higher values were found for the other dyes by the spectrophotometric method. The spectrophotometric pKa values paralleled the buffer/benzene ratios. The order of basicity varies in different media. It was not possible to correlate satisfactorily the secretion of dyes in a biological system with their ionization constants in aqueous or buffered 50% alcoholic solution.

Intravenous injections of de-hydroascorbic acid in rabbits in the dose 1 g/kg or 1.5 g/kg could not produce either persistent hyperglycemia or persistent diabetic type of glucose tolerance curve. Rabbits so treated neither excreted sugar in the urine nor showed any histological changes in the pancreas, suprarenal and pituitary. All these findings indicated that unlike rats dehydro-ascorbic acid is not diabetogenic in rabbits.

A variety of natural products have been examined by means of a rat-survival assay for their ability to relieve the stress induced by iodinated casein administration. Mammalian muscle and alfalfa have been found to be excellent sources of the protective material(s) being measured, with liver and yeast also containing significant amounts. 2. Materials most active in the survival assay have been demonstrated to reduce thymus and seminal vesicle atrophy and kidney enlargement. When low levels of iodinated protein are employed, the adrenals are also partially restored to normal by the protective substances. Under the conditions employed, the spleens are significantly larger in the protected than the unprotected animals and the testes are not reduced in size by the thyroprotein administration.

Use has been made of the ability of selenium to be fixed in red blood cells to estimate the intravascular life span of the duck erythrocyte. Donor ducks were injected with sodium selenate containing radio-selenium. These ducks were then bled and the red blood cells injected into 10 young ducks. Two each of the recipient ducks were bled at various time intervals up to 10 days. It was noted that there was a linear disappearance of selenium-tagged red blood cells from the circulation of the ducks. The value of 11.7 days was found to be the intravascular life span of the duck erythrocytes under the experimental conditions described here. In correlating the relationship between the disappearance of fixed erythrocyte selenium and the destruction of the red cell certain assumptions have been made which are discussed.

1. The incorporation of deuterium into cholesterol was studied in rats injected with thyroxine, in normal rats and in thyroidectomized rats. 2. It was observed that thyroxine stimulated, and thyroidectomy depressed, the incorporation of deuterium into cholesterol in the liver, intestine, kidneys and spleen, but not in the lungs. 3. In thyroidectomized rats, a lowering of the environmental temperature by approximately 20-28°C did not alter the rate of incorporation of deuteriuim into cholesterol in the liver.

1. Due to a species sensitivity, whose nature is as yet unknown, PVP cannot be considered as a suitable colloid replacement fluid for the treatment of “shocked” dogs. 2. Intact dogs were variable in their response to small intravenous doses, 0.03 to 0.5 cc/kg of clinical PVP, but reacted severely to intravenous injections of 3 cc/kg exhibiting hypo-tension; hemoconcentration, and flushing of the skin of several hours'duration. 3. A small molecular weight fraction of PVP (K-21) produced severe reactions, while with a larger molecular weight fraction (K-62) only insignificant changes occurred. 4. Monomeric vinylpyrrolidone, in quantities far in excess of those found in clinical PVP solutions caused only transitory hypotension when injected undiluted. 5. Cortisone, used prophylatically over a period of 5 days prior to an injection of 3 cc/kg of PVP, decreased the severity and duration of the “canine reaction.” 6. Bled dogs did not tolerate well an infusion rate of 4 cc/kg/min; no fatalities resulted from infusions at half this rate.

1. Growth hormone causes a marked reduction in urinary nitrogen output in the fasted phlorhizinized normal rat but does not have this effect in either the phlorhizinized adrenalectomized or the unphlor-hizinized normal or adrenalectomized animal. 2. In view of the ketogenic effect of growth hormone in the normal fasted rat and the absence of this effect in either the adrenalectomized, the phlorhizinized normal or phlorhizinized adrenalectomized rat the hypothesis is advanced that the ketogenic action of growth hormone is independent of its nitrogen retaining action and apparently requires the presence of the adrenal cortex for its appearance. 3. Growth hormone caused a marked reduction of glycosuria in the phlorhizinized fasted rat. This together with the reported increased glycosuria of alloxanized or ACTH treated rats after growth hormone lead to the conclusion that the diabetogenic action of growth hormone is indicative of a relative preponderance of the inhibitory action of growth hormone on peripheral glucose uptake over its action in reducing gluconeogenesis from protein in the liver.

A new type of electrically recording bristle flowmeter is described, which permits measurement of volume flow of blood and its phasic changes. By recording superior vena cava flow, direct evidence is presented that the greatest acceleration of blood and a marked volume inflow into the right atrium occurs during ventricular systole, when the tricuspid valves are closed. This demonstrates the active influence of ventricular contractions on venous return.

Hemorrhagic follicles in intra-splenic ovarian grafts in castrated guinea pigs appear irrespectively whether one or 2 ovaries are grafted into the spleen. On the contrary, hemorrhagic follicles fail to appear in an intrasplenic graft of the castrated guinea pig when the second ovary is grafted into the kidney. These experiments give definite evidence that the ovarian control of the hypophyseal gonadotrophic function depends not only, if at all, on consumption of gonadotrophins but certainly also on ovarian hormones which reach the general circulation.

When examined in vitro, streptomycin, penicillin, oxytetracyclene (“terramycin”) and neomycin were anticoagulants only when used in greater concentrations than can be attained in vivo.

1. A penicillium mold filtrate designated as 8450, and reported previously to have chemoprophylactic and chemotherapeutic activity against MM and Semliki Forest virus in mice, has been found to have demonstrable chemoprophylactic effects in 12 g mice infected peripherally with a special hamster passaged line of MEFl poliomyelitis virus. 2. Experiments are under way to find out (A) if stronger chemoprophylaxis can be obtained, (B) if more prolonged action can be obtained, and (C) if oral activity can be attained by 8450 against poliomyelitis virus.

The antibody formed by rabbits radiated with 400 r whole body radiation prior to; simultaneously with, or after immunization and by rabbits radiated with 800 r after immunization although often reduced in amount was indistinguishable from that formed by nonradiated rabbits.

The liver appears to be the main site of the conversion of pteroglyglutamic acid (PGA) to citrovorum factor (CF) in the body. Other tissues had very limited capacity to form CF, with the exception of bone marrow which, relative to the small amount present in this tissue, formed an appreciable quantity of the factor. The hepatic tissue of rats which had been depleted of folic acid and CF was flooded with CF within one hour following the intraperitoneal injection of PGA. Homogenates of rat or chick liver, when incubated with PGA under an atmosphere of nitrogen, were capable of forming CF. Little CF was found when similar preparations were incubated under oxygen. The yield of CF was consistently increased by the presence of ascorbate in the incubation mixture.

A simple, easily reproducible method for preparation of high-titer hemagglutinins with several arthropod-borne viruses is described. The method is based on the use of brains from newborn mice infected with virus as the source material, and on treatment with acetone and ether for the elimination of nonspecific factors. With this method, stable specific HA has been found associated with the following viruses: dengue (Hawaiian type), dengue (New Guinea B type), Ilhëus, Japanese B encephalitis, Ntaya, West Nile (Egypt 101 strain), and yellow fever (Asibi strain). As yet, no agglutination has been uncovered associated with Anopheles A, Eastern equine encephalitis, poliomyelitis (Type 2, MEF 1 strain), Russia Far Eastern encephalitis, and West Nile (original strain) viruses.

Neither rutin nor catechin altered the vascular lesions of hypersensitivity arteritis in rabbits or of experimental malignant hypertension in dogs.

An 8-day rat levator ani muscle assay for myotrophic activity is presented. Preliminary steroid screening results indicate that 19-nortestosterone and other 19-nor analogs of androgens promise to be effective protein-anabolic, and relatively weak androgenic agents. Using the same dose levels of 19-nortestosterone and testosterone, equal myotrophic responses were produced, yet 19-nortestosterone showed only weak androgenic activity and testosterone exhibited strong androgenic activity. Androsterone possesses relatively strong androgenic and only weak myotrophic activity.

1. Cortisone potentiates the effect of PTU on goitrogenesis in rats; a) thyroid and pituitary enlargement is greater than with goitrogen alone, and b) the respective changes in TSH levels of blood and pituitary are augmented. 2. The depressed avidity of thyroid tissue for I¹³¹ with PTU) is not influenced by cortisone. 3. The results suggest that the potentiating action of cortisone on goitrogenesis involves augmentation of TSH secretion from the adenohypophysis. The implications are briefly discussed.

1. Whole body x-irradiation of 650 to 725r results in depression of the normal bactericidal activity of rabbit serum. 2. With the x-irradiation doses employed, the bactericidal action of serum from rabbits is normal on the first post-irradiation day, is depressed by the fifth day following whole body x-irradiation and returns in surviving animals by the twentieth post-irradiation day. 3. Following a second dose of 650r, serum bactericidal activity is depressed earlier and remains depressed for a longer time than after the first 650r x-irradiation exposure.

The hydrolysis of succinylmono-choline iodide in normal and heat inactivated human plasmas was compared to the hydrolysis of succinyldicholine dichloride. In normal plasma, the hydrolysis rate of succinylmonocholine iodide was found to be about 8 times slower than that of succinyldicholine dichloride. In heat inactivated plasma, the hydrolysis rate of succinylmonocholine iodide was negligible in the 2-hour observation period. Succinylmonocholine iodide in 1.0 to 2.5 mg/ kg doses inhibited neuromuscular transmission in the sciatic-gastrocnemius preparation of cats.

1. Sodium thiosulfate in concentrations of 0.2 M or less produced no observable effects upon viral toxicity and infectivity. 2. Intracerebral inoculation of 0.075 M or less of sodium thiosulfate was well tolerated by mice. 3. Admixture of 0.1 M sodium thiosulfate with 5 × 10^-4 M cyclo mustard resulted in detoxification of the latter. 4. A possibly greater rate of destruction of viral toxicity by mustard, as opposed to viral infectivity, seemed to occur in the early stages of mustard-virus interaction. 5. Inactivation of viral toxicity by mustard proved complete, but the loss was not demonstrable in the viral progeny derived from eggs infected with one ID₅₀ of mustard-treated virus.