Experimental Biology and Medicine

The ability of the amputated forelimb of the tadpole to regenerate declines and in most cases is lost completely at the time of metamorphosis. However, .the present report shows that regeneration can be evoked experimentally in the adult frog if the number of nerve fibers available at the amputation surface of the forelimb is augmented by deviation of the sciatic nerve from the hindlimb. The theoretical considerations which led to these experiments emerged from the study of the influence of quantity of nerve fibers in regeneration in salamanders and are discussed here.

Studies on the biological activity of synthetic folinic acid show that it may replace pteroylglutamic acid in the diet of the chick.

Blood glutathione (GSH) and total glutathione (GSH plus GSSG) were determined in eleven patients during ACTH therapy and in eleven patients during the administration of cortisone. GSH values were significantly decreased from a pretreatment average of 36.6 mg per 100 cc to 26.9 mg by ACTH while cortisone produced a decrease from an average pretreatment value of 35.0 mg per 100 cc to 29.1 mg. The latter decrease, statistically, is of a low order of significance. The total glutathione values showed no changes following the administration of either ACTH or cortisone. During treatment with ACTH the greatest decrease in blood GSH occurred in the patients showing the greatest increase in blood sugar. There is suggestive evidence that although patients with normal glucose tolerance may show diabetic patterns during treatment, those who demonstrate mildly diabetic patterns prior to therapy show no further decrease in glucose tolerance and minimal reduction in GSH values after ACTH or cortisone therapy.

The technic of Potter(5) for measuring the effects of toxic agents on citrate accumulation in vivo was applied to studies on X-irradiation. Lethal doses of X-ray (800 r) markedly inhibited citrate accumulation in spleen, thymus, ileum, pancreas and testes of fluoroacetate-treated rats but exerted no significant effect on brain and heart. Sublethal doses of X-ray markedly inhibited citrate accumulation in spleen and thymus. The extent of inhibition was dependent upon the dose of X-ray and was reversible after sublethal doses and irreversible when lethal doses were given. Accumulation of citrate occurred in the livers of irradiated rats following fluoroacetate treatment in contrast to the inability of livers of normal male rats to accumulate citrate following fluoroacetate treatment.

The colorimetric esterase method of Gomori(5) was applied to studies on the cholinesterase activity of serum. The method was found to be applicable to studies on the action of anticholinesterase agents in vitro. It is also suitable for detecting exposure of humans to organic phosphorus-containing insecticides and for following serum cholinesterase levels during therapy with anticholinesterase drugs.

The mean serum complement titers of patients with various neoplastic diseases did not differ significantly from that for normal adults. The range of complement values was greater among cancer patients than among normals, but the erratic titers did not appear to be related to clinical status. No depression of human complement titer was observed following the clinical use of nitrogen mustard and x-ray in maximal dosage. Human complement is inactivated by high concentrations of nitrogen mustard in vitro, but not by concentrations in the range which is achieved in clinical usage.

Vit B₁₂ or liver extract administered to force-fed rats on constant food intake induced neither weight gain nor N retention. When vit B₁₂ was administered to force-fed rats on constant food intake, made hyperthyroid by injection of thyroxine, the weight loss was identical with that of hyperthyroid animals not receiving vit B₁₂. The N loss resulting from the catabolic action of thyroxine, however, was significantly smaller in thyroxine-treated rats receiving B₁₂ than in the thyroxine-treated controls. Liver extract had a, similar action, but the values obtained were statistically not significant. These results suggest that in hyperthyroid rats vit B₁₂ spares protein at the expense of other body constituents.

1. Aureomycin is more effective than chloramphenicol in inhibiting growth of three strains of Listeria monocytogenes in vitro. 2. More mice survived infection with L. monocytogenes when treated with aureomycin than with chloramphenicol.

Studies were made of the endogenous and succinate stimulated in vitro reduction of TTC by tissue slices from various human normal and cancer tissues as well as liver, kidney and spleen slices of control and tumor bearing mice. The per cent stimulation by succinate was not found to differ significantly in normal and tumor tissues. These findings were compared with previous studies of oxidative stimulation by succinate. It was also found shown that the presence of a tumor did not change the endogenous or succinate stimulated dehydrogenase activity of the liver, kidney or spleen of mice as measured by the TTC technique.

1. It has been observed that a pyridoxine deficiency in the rat does not disturb the normal conversion of tryptophan to liver pyridine nucleotides to any demonstrable extent. 2. Niacin fed to pyridoxine-deficient rats spares liver pyridine nucleotide concentrations. 3. Tryptophan fed in excess along with normal dietary protein in a complete ration increases liver pyridine nucleotides concentrations above normal demonstrating that the excess metabolite can be utilized rather than simply degraded and excreted.

In most laboratories, it is customary to treat new rubber stoppers with hot alkali and acid in order to remove surface impurities. But in the present experiments, based on more than 500 cultures, stoppers that were strongly toxic in the beginning remained toxic even after the most rigorous treatment. It should be emphasized that the toxicity of rubber stoppers is much more evident in cultures maintained in synthetic media than in media containing such naturally-occurring ingredients as blood plasma, blood serum and tissue extracts. For this reason, extreme care should be taken to avoid toxic stoppers in all experiments in which protein-free media are used. And since animal cells cultivated in synthetic media serve as extremely sensitive test objects, the information reported here can almost certainly be applied to other biological systems.

The application of the tetrazolium technic to a histochemical differentiation of the zonal activity of the various zones of the adrenal cortex is indicated. The functional activity of the cortical cells would appear to be paralleled by comparable changes in the ability of the cell to reduce tetrazolium. The implication of this type of approach to the problem of adrenal cytophysiology is discussed.

We are indebted to Mr. Jack Godrich for the microphotography in this study.

It has been reported by Fleming( 1 ), Florey( 2 ), Prickett, Miller and McDonald ( 3 ), 4 , Bradford and Roberts( 5 ) and others, that lysozyme is widely distributed in animal tissues and fluids. Although none of these authors attempted to assign structural function to this enzyme, it is interesting to note the frequent occurrence of lysozyme. Quantitative data relative to the enzyme is not available, although a number of qualitative tests, some of which approximated quantitative procedures, have been made. Since Smolelis and Hartsell( 6 ) described an accurate method for the determination of lysozyme from natural materials, it has been possible to accumulate more complete data.

Fleming( 7 ) reported that lysozyme was present in the white of eggs from the thrush, the wagtail and the moorhen. Is it probable that the concentration of lysozyme in tissues or fluids is determined, in part, by the heredity of the species? A study of the lysozyme content of a number of egg albumins was carried out as a first step toward an answer to this question. Samples were obtained from chicken, bantam hen, guinea hen, goose, duck, turkey, quail, pheasant, chuckar partridge, horned lark, herring gull, and although not avian in origin, a number of turtle eggs.

Methods. The fresh eggs were broken and the whites separated from the yolks. These whites were then pooled and blended in a Waring blendor for 5 seconds. After mixing, the material was distributed into small test tubes, quick frozen and stored at −9°C. By handling in this manner it was possible to carry out the assays at convenient times. Earlier work had shown that no loss in the titer of egg albumin occurred after storage for several weeks. Lysozyme determinations were made in accordance with the method described by Smolelis and Hartsell( 6 ). The results are presented in Table I. No calculated values are shown for the lysozyme contained in the goose or turkey egg albumins.

1. The clearance of intravenously injected reduced glutathione from the blood of dogs is rapid (< 30 min.). 2. The disappearance of subcutaneously injected glutathione from the body of the mouse is much slower (> 3 hours). 3. The distribution of injected reduced glutathione is not uniform throughout the body. Of the organs studied it concentrates to a considerable extent in the liver, spleen, and kidneys.

4. These experiments suggest that concentration of glutathione at sites vital for survival may be the prime factor in glutathione protection of the irradiated mammal. Whether the protection arises from preventing radiation death of essential cells or whether the protection is mediated through protection of humoral factors essential to orderly hemopoiesis remains unanswered.

A direct slide agglutination technic is described for determining the presence of agglutinating antibody in air-dried films of tissues and cells. This method has proved to be of value in correlating the appearance of antibody with cytological changes occurring at the site of antibody production.

Contrary to the widespread belief ( 1-6 ) that taste organs are dependent upon the trophic action of the gustatory nerve for development and maintenance, it has been demonstrated that amphibian taste organs can develop independently ( 7 , 8 ) and denervated organs can be maintained for at least 6 months ( 9 ). The present experiments not only support this, but extend the investigations to show that denervated taste organs can exist for at least 12 1/2 months.

To effect permanent removal of gustatory nerve influence, autoplastic grafts of tongue tip to orbit (eye and eyelids removed) were made in adult Triturus v. viridescens under light chloretone anesthesia. Before recovery from the anesthetic, the animals were wrapped in wet absorbent cotton and kept in moist chambers in the icebox for 48 hours to prevent accidental removal of the graft. They were then placed in aquaria where the graft would be bathed by water at all times. In 90% of the cases circulation was re-established within one week and the grafts “took.” In the process of establishment, varying amounts of resorption occurred. Also during the progress of the experiment the grafts tended to decrease in size. Animals were sacrificed according to the following schedule: daily for 30 days; on the 46th day; each month for 11 months; and at 12 1/2 months after operation. Histological sections of 64 heads were examined for taste buds on the grafts.

During the first week after operation the tongue graft epithelium became thin and flattened, and there was considerable edema and necrosis in the epithelium and underlying tissues. The extent of these reactions varied in the different grafts. Two days after operation, 26 taste organs were present in one graft. Other clumps of cells which may be distorted organs were also noted. Between the 2nd and the 14th day, no taste organs were visible in the specimens examined.

The extensive incorporation of glycine-2-C₁₄ into the purines of PNA and DNA has been shown in both cases to take place largely by an actual incorporation of the glycine molecule, and not by a simple exchange of urcide carbons. The main implication of this finding is that at least two pathways of DNA synthesis must exist.

Investigators at the Northern Regional Research Laboratory of the U. S. Department of Agriculture have recently reported the isolation in pure state of a new antibiotic, hydroxystreptomycin. It is produced by an organism, isolated from Japanese soil, which they believe to be different from other streptomycin-producing strains. The new species has been designated as Streptomyces griseocarneus n. sp. On the basis of degradation experiments, Benedict et al.( 1 ) have assumed that the new antibiotic differs from streptomycin only in having a hydroxy group in place of one of the hydrogens of the streptose methyl group. Accordingly, they have assigned the name “hydroxystreptomycin” to the new member of the streptomycin series.

One mg analytically pure hydroxystreptomycin trihydrochloride, when assayed against Bacillus subtilis, NRRL B-765 (ATCC 6633), was found to be equivalent to 784 jug of streptomycin base. The hydroxystreptomycin trihydrochloride used in these studies was prepared in the Northern Regional Research Laboratory and assayed 596 μg/mg (76% pure). The streptomycin sulfate assayed equivalent to 621 μg of pure free base per mg and was 78% pure.†

In the present studies we have compared the acute toxicity of hydroxystreptomycin trihydrochloride against the toxicity of streptomycin sulfate in white mice by subcutaneous administration. Both samples of streptomycin were dissolved in glass distilled water just before use, and the pH of each solution was measured with a glass electrode. The pH of a 10% solution of hydroxystreptomycin trihydrochloride was 7.1; that of a 10% solution of streptomycin sulfate was 4.8, which was adjusted to 6.2 with solid sodium bicarbonate. At least 10 mice (sexes equally divided) were used at each dosage level in determining the toxicity of the 2 streptomycins. For hydroxystreptomycin trihydrochloride, 46 mice were used and for streptomycin sulfate, 60 mice were used. The approximate LD₅₀, as determined by Trevan's method, was found to be as follows: for hydroxystreptomycin trihydrochloride, 865 mg/kg; and for streptomycin sulfate, 970 mg/kg.

Hemolytic streptococcal strains, virulent for chick embryos, were found able to utilize hyaluronic acid for respiration to a greater extent than relatively avirulent strains. With the micro-organisms tested, it appears that the hydrolytic products and not hyaluronate itself are utilized in respiration, such hydrolysis occurring presumably through the agency of hyaluronidase. Pathogenic bacteria frequently found associated with group A streptococci in vivo had a synergistic relationship with the latter in utilizing hyaluronate as a substrate for energy. On the basis of these findings, a mechanism of pathogenesis by hemolytic streptococci alone and with associated agents of infection was proposed. Certain clinical findings, interpreted as evidence for the existence of such a process, were cited.

It is a pleasure to acknowledge the assistance of Miss Clara Boyd.

An efficient and safe dialyzer‡ suitable for continuous operation under sterile conditions is described. It is made up of a variable number of component channels according to surface area desired. Sterility is accomplished by autoclaving as a whole and optional controlled ultrafiltration is possible.

Alloxan in relatively low and presumably nondiabetogenic dosages was found to be effective in preventing the development of murine bartonellosis, which invariably follows splenectomy in untreated carrier rats. The activity of this agent probably depends on its reaction with SH groups.

(1) Sarcoma 37 and malignant lymphoma were cultured as free cells in the peritoneal fluid of mice by serial transfers of these cells in the peritoneal fluid. Requisite number of tumor cells (100,000 or 1,000,000) were inoculated i.p into several groups of mice (S-37 in CFW or dba strain; lymphoma in dba mice only) and treated, after 2 to 14 days, with various doses (0.05 to 0.3 mc) of radioactive colloidal gold, either intraperitoneally or intravenously. In several series of experiments the mice were pre-treated with inactive (decayed) colloidal gold (0.1 or 0.2 cc) before the treatment with active gold. Control experiments investigated the growth characteristics of S-37 and lymphoma cells in untreated mice, the effect of the treatment with active or inactive gold in normal mice and the effect on tumor cells of radioactive gold stored in macrophages. (2) The experiments have outlined the role of the following factors in production of a radio-therapeutic effect of the radioactive colloidal gold on free tumor cells growing in the peritoneal fluid; (a) strain of the tumor; (b) strain of mice; (c) size of the inoculum; (d) interval between the inoculation and the treatment; (e) route of treatment; (f) dose of radioactivity; (g) pre-treatment with inactive gold. The effect was estimated by checking on the 6th day after the treatment, the percentage of surviving mice and the presence of tumor cells in the peritoneal fluid of treated mice and of controls. (3) The results were interpreted in the light of the data on growth characteristics of tumor cells and macrophagic reaction in the peritoneal fluid.

(1) CFW and dba mice were inoculated intraperitoneallv with Sarcoma 37 cells from serial intraperitoneal transfers. After formation of copious peritoneal exudate containing tumor cells and macrophages, these mice received intraperitoneally or intravenously 0.1 mc (in 2 series 0.3 mc) of radioactive colloidal gold. At various intervals (∗4 hour to 48 hours) after injection, specimens of peritoneal fluid were withdrawn from these mice and centrifuged. Radioactivity of precipitate (P) and of supernatant (S) in each specimen was determined by Geiger counter. (2) Ratio P/S was accepted as index of radioactivity distribution between macrophages and serous exudate of the peritoneal fluid. Data illustrating trends in changes of P/S in various groups of mice were plotted in graphs and discussed. These data were interpreted as the combined effect of two parallel phenomena responsible for disappearance of radioactive colloid from the peritoneal serous exudate; (a) absorption and storage of colloid particles into macrophages; (b) their diffusion into circulating blood; (3) The ratio P/S in various specimens of peritoneal fluid from the same mouse remained consistently on higher levels after (a) the use of higher doses of radioactive colloidal gold; (b) the use of dba mice and (c) the preparation with inactive (decayed) colloidal gold before treatment with radioactive gold. The effect of these factors is attributed to the increase in the number and in the activity of macrophages.

1. Pneumoperitoneum produces (a) an intra-abdominal herniation of the lower end of the eosphagus (b) a ptosis of the stomach, liver, spleen and the root of the mesentery, displacing the first 3 structures from beneath the costal margin and therefore making them more accessible for surgical procedures. 2. Pneumoperitoneum employed in the dog, prior to total gastric resection, proved valuable. As a result of the intra abdominal herniation of the lower segment of the esophagus, the displacement of the cardia of the stomach to the level of the costal margin, and the mobility of the root of the mesentery, the stomach was readily resected and an esophagojejunostomy established.

Veriloid, a reproducible hypotensive derivative of Veratrum viride, was administered in dosage of 1 mcg/kg/minute for 10 minutes to unanesthetized dogs. Similarly the veratrum derivative was administered to unanesthetized dogs premedicated with toxic dosages of digitalis preparations and to others premedicated with toxic dosages of quinidine hydrochloride. The degree of cardiac slowing from the veratrum derivative was found to be a function of pre-existing cardiac rate. No such relation was found for the bradycardia produced by digitalis. Dogs which received digitalis and veratrum showed profound bradycardia. This action appeared to be mediated by increased vagal tone since the slowing was abolished by atropine. Rhythm disturbances due to digitalis were exaggerated by veratrum. A rise in Q-T/R-R ratio above that to be expected by changing cardiac rate was associated with the administration of quinidine hydrochloride. In normal animals and in those which received digitalis, Veriloid or both, the ratio was found to vary as a straight line function of the existing heart rate. Neither quinidine alone at IS or 25 mg/kg nor quinidine and veratrum produced appreciable incidence of arrhythmias. Cardiac slowing was observed in dogs receiving veratrum after the 15 mg/kg dose of quinidine but not after the 25 mg/kg dose.

Tri-ethylene melamine decreased the total white blood cell counts and the percentage of mononuclear cells. The total white blood cell counts returned to normal between the sixth and tenth days after injection and the mononuclear count returned to normal after one month. The highest percentage of deaths after single injections occurred between the third and sixth days when the total white blood cell counts were lowest. Surviving animals developed a resistance to a second injection, which manifested itself in a long latent period. Nine out of fifteen of the deaths in the latter group occurred between the ninth and thirty-first days, during which period the white blood cell counts were normal. The median lethal dose after a second injection was considerably lower due to the cumulative effect. The toxic effects of tri-ethylene melamine were evidenced in the dramatic fall in white blood cell count and decrease in percentage of mononuclear cells. However, the return to a normal blood picture was no indication that the effects of the drug had been extinguished.

(1) Both aureomycin and terramycin administered subcutaneously, either prophylactically or therapeutically (4 hours after infection) to white mice infected intra-peritoneally with 1,000 MLD₁₀₀ of P. multocida prolonged survival and lowered the fatility rate. Aureomycin was distinctly superior to terramycin; a single dose of 2 mg (133 mg/kg) of aureomycin resulted in a survival rate of approximately 87%, whereas that of the mice treated with terramycin was approximately 47%. Smaller doses (1 mg and less) of both antibiotics were less effective. Treatment over a period of 6 days did not increase substantially the survival rate as compared to a single dose treatment on day of infection. (2) In vitro neomycin was of the same bacteriostatic potency as streptomycin against 7 strains of P. multocida and was markedly superior against the eighth, streptomycin-resistant, strain.

Benadryl, an antihistamine and three steroids, cortone, allopregnane and pregnenalone do not affect the course of experimental apppendical peritonitis in dogs.

1. In mice, methoxinine causes a reduction in the food consumption and a weight loss. 2. The toxic effects of methoxinine are alleviated by methionine. 3. Methoxinine is not lipotropic in mice, since the caloric restriction imposed by its toxicity can completely account for its “apparent” lipotropic activity.

Vit A administered topically to the skin for 10 days resulted in an average increase, in epidermal thickness to about twice normal. A notable increase in the extent of the stratum granulosum occurred, and a decreased rate of keratin formation and/or an increased rate of keratohyalin formation are suggested. The effect was apparently entirely local; untreated skin areas from vitamin treated animals showed no significant alterations. Estrogen resulted in no observable change in the epidermis and did not counteract the stimulatory effect of the vitamin.

Auxin (3-indoleacetic acid)at a concentration of 3.5 mg/1 in the medium causes a striking increase in the ascorbic oxidase activity of cultured tobacco pith sections. This is subsequently accompanied by a lesser respiratory increase, by cell enlargement, and by gains in fresh and dry weight. No cell divisions occur. Since the ascorbic oxidase activity of homogenates is localized in the cell wall fraction obtained by differential centrifugation, it is suggested that the enzyme occurs in cytoplasm intimately associated with the wall. Vigorous ascorbic oxidase activity is characteristic of a variety of actively growing plant tissues examined. It is suggested that ascorbic oxidase may be causally related to cell growth.

1. Experiments on rats—sensitized to mineralo-corticoid actions by unilateral nephrectomy and a high sodium intake—showed that somatotrophic hormone (STH) shares with desoxycorticoster-one acetate (DCA) the ability to produce: cardiac hypertrophy with histologic signs of a rheumatic-like myocarditis, hypertension, renal enlargement with microscopic evidence of malignant nephrosclerosis and an increased water turnover with proteinuria. 2. All these actions are greatly increased when STH and DCA are administered simultaneously, except for the rise in blood-pressure. The failure to develop hypertension under the influence of the two preparations may well be due to the fact that this hormone combination is extremely toxic and causes pronounced edema with obvious deterioration in the physical state of the animals. 3. It is concluded that STH sensitizes the tissues to the production of “collagen-disease-like” lesions by DCA. 4. STH also causes adrenocortical enlargement and prevents the compensatory atrophy of the adrenal cortex normally elicited by DCA. This effect may be due: to a contamination of our preparation with ACTH, to the compensatory secretion of ACTH by the pituitary of the STH-treated animal, or to a true corticotrophic action of STH. 5. Although earlier experiments had shown that even electrophoretically pure STH causes similar adrenal stmulation, we have no evidence either for or against the view that STH induces the adrenal cortex to produce miner-alo-corticoids. The “umineralo-corticoid-like” actions of STH could result solely from the sensitization of the peripheral tissues by STH. Increased mineralo-corticoid production by the adrenal cortex under the influence of STH may be an additional factor, but its possible participation remains to be demonstrated.

Purified elastic material from fish swim bladder was fragmented and observed under the electron microscope. Elastic fibers were digested with unfiltered trypsin and also with trypsin sterilized by filtering through a Seitz microfilter. When digestion is not done under absolutely sterile conditions, “fine threads” described by Gross(2) as a component of the elastic tissue are observed.

If digestion is performed under complete sterile conditions no threads appear, and only partially digested elastic fibers can be found. Incubation of trypsin alone also shows the presence of threads when sterilization is not used and their absence in sterile conditions. The conclusion is reached that the threads described as a component of elastic tissue(2) belong to material digested from bacteria and probably from bacterial flagella.

Progressive and usually fatal amebic hepatitis can be induced readily in golden hamsters by the intrahepatic injection of a strain of Endamoeba histolytica and its bacterial associates from cultures. Amebae rather than bacteria appear to constitute the major etiologic agents in producing the hepatitis.

Hexamitiasis, a protozoan disease of turkeys, of considerable economic importance, has been described by Hinshaw 1 . Up to the time at which we began our studies June 2, 1950, there were no reports of any effective means of medication for the control of this endemic and frequently acute disease. A group of 9-week-old Broad Breasted Bronze poults, which had been reared in wire-floored batteries without contact with ground or other birds was employed. Several field cases of severe hexamitiasis were obtained and the hexamita collected in large numbers from the small intestine. The organisms were suspended in saline and equal doses of this suspension were introduced by pipette into the crop of each poult. In the following report, number of days indicated refers to time from this inoculation.

At the end of 5 days all birds appeared ill. Three were killed and found to have heavy infection of hexamita in the small intestine. The organisms were identified by microscopic study of smears from the small intestine 1 . The remaining birds were treated as follows.

Control group. At the end of the 8th day this group appeared very ill. Three birds were killed for examination. All 3 showed heavy infection and a marked dehydration which is characteristic of this disease. The remaining 3 birds were fed a rearing mash containing 0.1% Enheptin∗ to the 12th day. One of these birds was then found to be free of detectable hexamita while 2 showed a very light infection. All were recovering from dehydration and appeared alert and vigorous.

Enheptin group. At 5 days, 6 of the diseased birds were given 0.1% Enheptin in mash. At 8 days 3 of these birds were found free of hexamita and noticeable dehydration. At 14 days the remaining 3 birds maintained on the

Certain amino acids reduce considerably the nephrotoxic action of meralluride sodium in the rat. Among the amino acids examined 1(+) arginine monohydrochlorid and glycine were found to be most effective. The beneficial influence seen in microscopic sections as well as in the reduced proteinuria following a toxic dose of the mercurial diuretic is attributed to the competitive suppression of tubular reabsorption of the injurious mercury.

The participation of glycine in the biosynthesis of cytochrome c has been demonstrated. Under our conditions, the incorporation of C14 from glycine-2-C14 was of relatively very low order in the cytochrome c of heart and very high order in liver tissue which had undergone active regeneration. The data support the conclusion that in regenerating liver cytochrome c is fabricated in situ and not derived from other tissues. A rate of “turnover” for liver cytochrome c has been provisionally deduced, which is appreciably higher than the normal rate of hemoglobin “turnover.” It is tentatively proposed that chromoprotein biosynthesis is a general property of living, aerobic cells.

Four closely related alkaloids-longilobine, retrorsine, α- and β-longilobine -have been compared in mice by intravenous injection. There is no significant difference in their toxicity as measured by the median lethal doses. All 4 substances produce liver damage with central necrosis as the predominating lesion.

Chloramphenicol, aureomycin, terramycin and nitroacridine 3582 inhibit the formation of certain adaptive enzymes in E. coli. This effect per se is not responsible for the bacteriostatic activity of these substances, but it probably points toward a general interference with protein metabolism of the organism.

The toxicity of colchicine, DFP, Intocostrin and KCN was increased in mice that were exposed to 4°C for 24 hours and maintained in the cold after injection. Animals that were acclimatized to the cold were no more susceptible to DFP than were controls treated at room temperature. The possible factors implicated in these findings are discussed.

The work of Carson and Campbell(l), which reported the fungistatic action of 3 antihistaminics, prompted an investigation concerning which the following is a preliminary report. In addition to testing fungistasis by several antihistaminics, we were also interested in determining whether the compounds are fungicidal as well. Lastly, it was considered of fundamental biochemical interest to determine whether the antifungal action of antihistaminics is based on interference with utilization of histamine (or a compound or compounds of similar structure) by the fungus.

The compounds studied were as follows: Benadryl. (Diphenhydramine HC1) Parke-Davis : Thephorin, (Phenindamine Tartrate) Hoffmann-La Roche; Thenylene, (Methapy-riline HC1) Abbott; Neo-Antergan, (Pyran-isamine Maleate) Merck; Pyribenzamine, (Tripelenamine EC1) Ciba, and Diatrine, (Metaphenilene HCI) Wm. R. Warner. The test culture employed was Trichophyton mentagrophytes (Emmons No. 640).

A slight protection of guinea pigs treated with rutin and subjected to an LD50 dose of histamine has been confirmed. The failure of certain other investigators to substantiate this finding may have been due to excessive histamine dosage or the use of inadequately standardized animals. Quercitrin, quercetin and methyl hesperidin chalcone also were found to afford protection against histamine. The protection is slight and is of theoretical rather than clinical interest.

The subcutaneous LD₅₀s of 25% PABA, 5% DEAE, and 5% DMAE in mice were found ito be 4.39, 1.61, and 2.08 g/kg respectively. Subcutaneous premedication by l g/kg of 7% PABA did not alter the LD₅₀ of intravenous procaine in mice, while subcutaneous premedicatlion by 0.5 g/kg of either 5% DEAE or 576 DMAE lowered the LDSO about 35%. Neither PABA, DEAE, nor DMAE changed the rate of disappearance of procaine from the whole body of the mouse. It is concluded that the influence observed to be exerted by DEAE and DMAE on the toxicity of intravenous procaine is probably due to their additive toxic effects on the cardio-vascular system, and not to the inhibition of procainesterase in vivo.

There was no significant effect of adrenalectomy or cortisone treatment upon the phosphocreatine or, 4TP content of rat muscle.

In an encouraging but limited number of white mice infected with a rapidly fatal toxoplasmosis, Diasone and Promin have not only suppressed the symptom but have repeatedly eliminated the carrier state, Symptom-freed, promin-treated mice have survived over a year but Diasone appears to be less toxic and more potent since it protected mice when therapy was delayed for of the survival time of simultaneously infected, untreated mice.

The addition of generous amounts of folic acid, or folic acid and vit B₁₂, to experimental diets had no significant effect on the survival of mice injected with a dose of P³² in the higher range of the LD₅₀ (21st day). On the other hand, when sulfasuxidine was added to the diet and the mice were injected with a dose of P³² slightly below the LD50 (21st day), the administration of vit B₁₂ and folic acid increased significantly the time of 50% deaths, the average time of survival and the % of survivors (at both the 21st and the 56th day).

The development of the property O in the newborn and in young children, investigated from the point of view of the agglutinability and group-specific absorbing power with an immune anti-Shigella dysenteriae goat serum, is comparable to that of the agglutinogens A and B, namely, the agglutinability and the absorbing power are both extremely poor at birth, but increase until after 3 to 5 years their values become equal to those of the adult. Saliva from newborn and children of group O of the “secretor” type, neutralizes anti-0 serum approximately to the same degree as saliva of adults of group O. The results obtained seem to contradict recent investigations which consider the so-called anti-0 sera to have only an anti-H specificity. Probably, anti-0 sera contain a mixture of serologically related antibodies to some of which cannot be denied an anti-O specificity sensu strictiori.

Suspensions of living lymphocytes decolorize the oxidation-reduction indicator, 2,6 dichlorophenol indophenol. This reduction was inhibited by the cytotoxic agents, lipo-adrenal cortex, cortisone, nitrogen mustard and x-rays but was not affected by desoxycorticosterone. The method was used to titrate lipo-adrenal cortex, the titer being .00,08 rat unit. This color test seemed to be a convenient method for demonstrating and measuring the toxicity of the adrenal cortex hormones to lymphocytes.

The spread of an hemoglobin spot was studied under various hormonal conditions. At the dose level utilized, cortisone antagonizes the enhancement of the spread normally occasioned by STH, thyroxine and LAP. Our results confirm the antagonism between DCA and cortisone first suggested by Selye( 8 ) concerning their action on vessels and inflammation. LAP, STH and thyroxine in this respect have a DCA-like action opposite to the effect of cortisone.

ACTH did not reduce the acute toxic effect of influenza virus in mice or rats nor the similar action of the rickettsiae of murine and epidemic typhus in mice.

Examination of 10 rats sacrificed 18 months after a single injection of 400 μc of radioactive iodine revealed the following changes in the thyroid gland: 1. Hürthle-like elements (previously reported by us in thyroids of rats sacrificed 8 months after a single I¹³¹ injection) were evident in the parenchyma of all glands. 2. Multiple adenomata, apparently benign in nature, were found in the thyroids of 2 rats. 3. Two types of anaplastic, nonencapsulated neoplasms, one of which was invading adjacent thyroid tissue, were also found in the thyroids of these 2 rats.

1. A fatal encephalitis develops in 7-day-old albino rats following nasal instillation or intracerebral injection of Japanese B encephalitis virus. 2. The virus produces a uniformly fatal infection in 7- and 8-day-old rats when injected intraperitoneally. 3. While some 12-day-old rats are susceptible to the virus when inoculated either by the intracerebral, intraperitoneal or intranasal route they are more resistant than 7- and 8-day-old rats. 4. Rats 21 and 27 days of age appear to be resistant to the virus since when it is injected intracerebrally into animals of this age it does not induce a clinically apparent infection.

Data are presented which suggests that inapparent infections with influenza viruses may occur after continued exposure for relatively long periods of time.

The distribution of mumps virus in one experimentally infected monkey 96 hours after inoculation has been investigated by simultaneous labelled antibody and virus isolation studies. The results furnished by the two methods were in fair agreement. Virus was demonstrated in CNS (brain and spinal cord) as well as in both parotid glands, although the animal had shown no neurological signs. No virus was demonstrated in the other organs examined.

Under conditions of vit. C deprivation, folic acid has no apparent antiscorbutic effect in guinea pigs.

After intraperitoneal or subcutaneous injection, an aqueous solution of sodium thioglycollate markedly reduces water diuresis in rats and cannot be used by either route to demonstrate unequivocally whether posterior pituitary antidiuretic principle has been inactivated. By the intravenous route in rats, thioglycollate does not interfere with diuresis and can be shown, as in the dog, to abolish the antidiuretic action of Pitressin. Therefore, there is no controlled experimental evidence that Pitressin contains more than one antidiuretic principle.

The topical application of acetylcholine or related parasympathomimetic drugs to the mucosa of canine fundic pouches results in the secretion of alkaline opalescent viscid mucus which is free of columnar cells. These studies confirm our previous conclusion, that the exfoliation of gastric surface cells is not an essential part of the process of mucus secretion.

Ad libitum feeding of a low or moderate fat diet containing 1% cholesterol to rhesus monkeys resulted in a greater hypercholesterolemia in the pyridoxine deficient monkey than it did in the control monkey. This occurred despite the fact that the cholesterol intake of the control animal was 2-4 times greater than that of the deficient animals.

Modification of arterial tension by cortisone, in the doses generally employed, has been noted but rarely in short-and long-term observations of subjects without renal disease. A rise in blood pressure has been the rule among patients with renal damage of varying types irrespective of the presence or absence of antecedent hypertension.

Hyaluronidases produced by strains of Groups A and B streptococci are serologically distinct. Hyaluronidases produced by strains of Groups C and G are serologically indistinct. Each of the latter is distinctly different from hyaluronidases formed by strains of streptococci, Groups A and B.

1. Animals receiving arginase treatment did not die of their implanted tumors during the 21-day period. The controls (Group “A”) and those receiving arginine (Group “B”) died within this period. 2. Those animals receiving arginine indicate a tumor length weight ratio increase of 7.9% over group “A”. 3. The group receiving arginase (Group “C”) exhibited a 28% decrease in size as compared to the controls in group “A”. 4. The ratio of tumor length to weight was 26% lower in the group receiving arginase. 5. Tumor specific volume (tumor length to weight) is offered as an accurate tumor measurement method.

Phenyl thio carbamide is known to divide the adult population into 2 groups, those capable of tasting its intense bitterness (T) and those to whom it is tasteless (t). The capacity for tasting or failing to taste the compound is inherited according to Mendelian laws. It is demonstrated that the ability to taste or not to taste this compound is demonstrable in early infancy and it is suggested that such data can be profitably employed in cases of doubtful paternity in situations where a tasting child is born to a non-tasting mother.

1. The ratio of red cell space for inorganic iodine to that of plasma was found to be about 0.5, in both in vitroc and in vivo studies. 2. The initial red cell-plasma ratio was the same in hyperthyroid, euthyroid, and hypothyroid patients immediately after the oral administration of a test dose of I¹³¹. 3. The ratio dropped as the inorganic iodine test dose was incorporated into larger molecules by the thyroid and returned to the blood stream. 4. The drop in red cell-plasma ratio was due to the relative impermeability of the red cell to large iodine-containing molecules. 5. The rate of drop of the red cell-plasma ratio is an expression of thyroid activity.

1. The experiments described indicated that cortisone inhibits the synthesis of chondroitin sulfate by embryonic and wound tissues maintained in vitro. Graded responses were obtained with graded concentrations of cortisone in the medium. Cortisone was shown to inhibit the synthesis of soluble organic sulfate by heart and skeletal muscle; it had no such effect upon the synthesis of soluble ester sulfate by liver tissue. 2. Concentrations of cortisone which suppressed sulfate fixation, had no apparent effect upon the initial migration of fibroblasts. Cortisone had no effect upon the pulsations of heart tissue. 3. It was suggested that the palliative action of cortisone in the connective tissue diseases may be due to its inhibitory effect upon the synthesis of the chondroitin sulfate moiety of the connective tissue ground substance.

The red fraction, previously isolated from a stenothermophilic bacterium, represents a specific piece of bacterial protoplasm. The evidence presented consists of photographs taken with the phase contrast microscope, photomicrographs of stained preparations of bacteria and of red fraction, and of enzymatic data. The enzymatic data rest chiefly on the presence of succinoxidase activity.

The present data indicate that the action of DOCA is not limited to a control of the transfer of sodium from the lumen of the kidney tubule to the surrounding blood stream but also influences the transfer of sodium from the lumen of the intestine to the surrounding blood stream. DOCA, in addition, influences the transfer of sodium through the sweat and salivary glands by decreasing the sodium concentrations in their secretions (13,14). The evidence indicates that DOCA affects the transfer of sodium through various organs, among them the colon, in each instance limiting the escape of sodium from the body.

1. Bilateral cortical necrosis of the kidneys was observed in rabbits which were treated with large doses of cortisone and then given a single intravenous injection of meningococcal or S. marcescens (P-25) toxin. This lesion did not occur when animals were given injections of cortisone alone, or toxin alone. 2. A similar renal lesion occurred in cortisone-treated Syrian Hamsters following an intraperitoneal injection of P-25 toxin.

Study of hypophysectomized dogs that manifest (a) atrophic changes in all three cortical layers of the adrenals, (b) severe disturbances in carbohydrate and protein metabolism and (c) reduced renal functions (glomerular filtration rate, renal plasma flow and tubular transfer maxima) reveals that: (1) their ability to excrete an orally administered water load is impaired, (2) their ability to withstand sodium restriction is normal and (3) their renal tubules retain the ability to excrete potassium and the animals are able to handle potassium loads almost as well as the normals.

Continued administration of purified growth hormonc significantly improves the hypophysectomized dog's impaired response to water load. Concomitantly it increases the daily water exchange to levels seen in surgically induced diabetes insipidus. Growth hormone increases the glomerular filtration rate and renal plasma flow of hypophysectomized dogs but not to the pre-operative levels. It is suggested that growth hormone is one of the factors concerned with the maintenance of normal water metabolism.