bluuebunny/crossref_metadata_2025_split huggingface dataset:
ANTIMICROBIAL AGENTS IN THE PREVENTION OF DIETARY HEPATIC INJURY (NECROSIS, CIRRHOSIS) IN RATS
Authors: György Paul , Stokes Joseph , Goldblatt Harry , Popper Hans 
Published: June 2004

The effect of various antimicrobial agents, such as aureomycin, terramycin, streptomycin, chloromycetin, penicillin, polymyxin, and sulfaguanidine on the development of massive dietary necrosis of the liver in rats has been studied. Delay in the production of hepatic necrosis was obtained from aureomycin and, to a lesser extent, from terramycin and streptomycin. Indication of temporary protection was shown by sulfaguanidine, whereas chloromycetin, polymyxin, and penicillin were not protective.
B12, added alone, or in combination with aureomycin, to the basal experimental diet had no influence on the development of hepatic necrosis. A combination of pectin with streptomycin enhanced the protective effect of the antibiotic.
All the antimicrobial agents tested, without relation to their effect on hepatic necrosis, produced temporary stimulation of growth in the experimental animals.
The beneficial effect of aureomycin was not limited to the delay of hepatic necrosis but manifested itself also in the prevention of hepatic cirrhosis in rats fed a low protein (casein)-high fat diet. In contrast to control animals showing the usual combination of cirrhosis and renal changes, the rats receiving supplements of aureomycin were free of both cirrhosis and renal changes. The rats receiving aureomycin took more food in and gained weight.
No microscopic alterations were seen in the pancreas of the control rats with cirrhosis.
In both groups of experiments (necrosis and cirrhosis) the antimicrobial agents, with the exception of penicillin, were given mixed with the food. Their possible effect on the intestinal flora is discussed.
VARIABILITY OF BCG STRAINS (BACILLUS CALMETTE-GUÉRIN)
Authors: Suter W. Emanuel , Dubos René J. 
Published: June 2004

Three different cultures of BCG propagated for over 2 years in a liquid medium containing Tween 80 and albumin were found to differ in several of their intrinsic properties.
Cultures of the three strains were found to consist of morphologically heterogeneous populations—each culture being made up of three main colonial types—spreading, intermediate, and non-spreading. The percentage distribution of colonial types was characteristic for each culture and remained constant during cultivation in liquid media.
Injection of the various cultures into mice and guinea pigs resulted in a self-limited disease. The distribution, extent, and duration of the lesions were also characteristic for each culture.
Both the spreading and non-spreading substrains derived from the various cultures exhibited the degree of attenuation of virulence characteristic of the parent strain.
STUDIES ON ACUTE DISSEMINATED ENCEPHALOMYELITIS PRODUCED EXPERIMENTALLY IN RHESUS MONKEYS
Authors: Kabat Elvin A. , Wolf Abner , Bezer Ada E. , Murray Jean P. 
Published: June 2004

The white cell count, total protein, gamma globulin, and percentage of gamma globulin in the cerebrospinal fluid of monkeys with acute disseminated encephalomyelitis produced by the injection of brain emulsions with adjuvants have been studied.
The acute phase of the disease is characterized by a rise in the white cell count, total protein, and gamma globulin in the cerebrospinal fluid. In some instances the percentage of gamma globulin, to the total protein may be normal while in others it is elevated.
As the acute process subsides, the total protein declines and animals frequently show an increase in the percentage of gamma globulin to total protein. The relation of the cerebrospinal fluid findings in acute disseminated encephalomyelitis in the rhesus monkey to those in human multiple sclerosis is discussed.
THE RELATION OF THE KREBS CYCLE TO VIRAL SYNTHESIS
Authors: Ackermann W. W. ,   With the Technical Assistance of Elaine Kleinschmidt and Hilda Kurtz
Published: June 2004

A further study has been made of the relationship of reactions of the Krebs cycle to the propagation of influenza virus. By the administration of sublethal doses of sodium fluoroacetate which were found to increase the concentration of citrate in the mouse lung, it was possible to demonstrate a blocking of the citric acid cycle in that organ. Further, the intraperitoneal administration of these concentrations of fluoroacetate was found to inhibit markedly the propagation of influenza, Type A, virus in the lungs of mice.
The inhibition was observed when the fluoroacetate was administered 15 minutes, 6 hours, or 12 hours after the mice were inoculated with virus. This effect was also demonstrable when the concentration of the viral inoculum was varied over a range of virus titers from 103.5 to 106.5.
Sodium fluoroacetate was found to have no effect in vitro on the infectivity or hemagglutinating property of the virus.
The significance of these findings with regard to chemotherapy and to the mechanism of viral synthesis is described.
LOCALIZATION OF ADRENOCORTICOTROPIC HORMONE BY HISTOCHEMICAL AND IMMUNOCHEMICAL METHODS
Authors: Marshall John M. 
Published: June 2004

The fluorescent antibody technique was adapted to the localization of native protein antigens in cells and tissues. This method was applied specifically to the localization of adrenocorticotropic hormone in the pituitary gland.
An antiserum to hog ACTH was produced in an adrenalectomized rabbit. The γ2-globulin fraction of the serum was conjugated with fluorescein. After purification, the fluorescent antibody solution stained selectively the cytoplasm of basophil cells of the hog pituitary. No cells of sheep or beef pituitary or of hog kidney were stained. A fluorescent globulin solution prepared from normal rabbit serum gave no selective staining in any of these tissues.
Immunochemical tests showed that the fluorescent antibody gave a precipitin reaction with a highly active ACTH preparation of low molecular weight. The supernatant solution from this reaction showed a loss of hormone activity.
INFLUENCE OF THE PHYSIOLOGICAL BLOOD CLOTTING PROCESS ON THE COAGULATION OF BLOOD BY STAPHYLOCOAGULASE
Authors: Tager Morris , Lodge Anne L. 
Published: June 2004

The conversion of plasma to serum results in a variable loss of the coagulase-reacting factor (C.R.F.) of the plasma.
The C.R.F. loss is incurred during the process of prothrombin conversion: conditions which favor the most effective prothrombin conversion result in maximal C.R.F. loss, while factors which interfere with prothrombin conversion spare the C.R.F.
In a system containing an adequate concentration of calcium, thrombo-plastin, and prothrombin, the C.R.F. loss reflects the amount of prothrombin conversion-accelerating substances (factor V or AC globulin).
If fibrin clots are produced directly by thrombin, and prothrombin conversion is excluded, there is no significant C.R.F. loss.
A SPECIFIC COMPLEMENT-FIXATION TEST FOR INFECTION WITH POLIOMYELITIS VIRUS
Authors: Casals Jordi , Olitsky Peter K. , Anslow Ralph O. 
Published: June 2004

A complement-fixing antigen has been developed, using as source of material CNS tissue from newborn mice infected with the newborn mouse-adapted strain of the Lansing type, MEF1 virus. With this antigen, specific reactions have been obtained with sera from mice, cotton rats, and monkeys immunized with the Lansing-type virus, and from monkeys and chimpanzees convalescent from infection with this virus.
Twenty-one of 35 human sera obtained from individuals convalescent from poliomyelitis were positive and 6 of 22 from apparently normal persons having Lansing-neutralizing antibody, while this held true for only 1 of 19 from those having no Lansing-neutralizing antibody.
The fact that positive results were found in sera from patients having an infection with poliomyelitis virus of the Brunhilde type and at the same time no Lansing-neutralizing antibody brings up the possibility of the existence of a cross-reaction in complement fixation between the two types.
INHIBITION OF ESCHERICHIA COLI BY p-AMINOBENZOIC ACID AND ITS REVERSAL BY p-HYDROXYBENZOIC ACID
Authors: Davis Bernard D. 
Published: June 2004

p-Aminobenzoic acid (PABA) exerts three metabolic effects on E. coli: it acts as a normal vitamin at low concentrations, as a source of another vitamin, p-hydroxybenzoic acid (POB), at moderate concentrations, and as a growth inhibitor at high concentrations (150 to 1600 µg./ml.). The inhibition is competitively reversed by POB in 1/100 the concentration of PABA. The inhibition is also reversed to a limited extent by shikimic acid and compound X, precursors of POB.
p-Nitrobenzoic acid is an inhibitory competitor of both POB and PABA.
The retardation of growth produced by PABA and other competitive analogues of POB (p-nitrobenzoic acid; 4,4'-dihydroxydiphenyl sulfone; phenosulfazole) is converted to complete bacteriostasis by the addition of L-aspartic acid in a remarkably low concentration (1 µg./ml.)) without change in the competitive ratio with POB. The mechanism underlying this synergism is not clear.
In contrast to wild type, mutants that require POB not only are inhibited by much lower concentrations of the above analogues, but also show inhibition by weaker competitors of POB such as p-hydroxybenzenesulfonamide, p-chlorobenzoic acid, and p-fluorobenzoic acid.
OBSERVATIONS WITH THE ELECTRON MICROSCOPE ON THE SOLVATION AND RECONSTITUTION OF COLLAGEN
Authors: Vanamee Parker , Porter Keith R. 
Published: June 2004

The course of events in the solvation and reconstitution of collagen obtained from rat tail tendon is described as seen with the electron microscope. Under the influence of 0.01 per cent acetic acid the collagen fibers swell and dissociate into submicroscopic filaments, the smallest of which are probably beyond the resolution of the electron microscope. These filaments can be made to reconstitute into fibers either by the addition of neutral salts to the acid solution or by raising the pH. The structural form of the resulting fibers is influenced by the concentration of the salt and by the pH of the solution employed. Saline-concentrations around 1 per cent and pH's ranging from 4.8 to 6.8 lead to the formation of needle-shaped crystals, or tactoids, showing the striated structure characteristic of collagen. Saline concentrations outside of this range (0.5 per cent and 5.0 per cent) lead to the formation of long fibrils without evidence of striations. pH's on the alkaline side of 6.8 bring about the formation of long slender fibers. Some of the possible reasons for these different fiber forms are discussed.
Apparently fibers are formed in vitro by the lateral and longitudinal association of the filaments seen in the original solutions. Some of the fibers thus formed may in turn associate laterally and longitudinally to form the larger fibers.
The formation of the needle-shaped crystals appears to be an orderly process since it leads to the formation of a periodicity in the fibers. The striations in the smaller fibers are uniform and regularly spaced at around 210 A. With continued growth of these fibers there is a simultaneous development of a more obvious and precise banding. It is evident that two out of each group of three regularly spaced striae are more prominent. This produces the macroperiod of collagen measuring around 640 A in length.
STUDIES ON HOST-VIRUS INTERACTIONS IN THE CHICK EMBRYO-INFLUENZA VIRUS SYSTEM
Authors: Liu Oscar C. , Henle Werner 
Published: June 2004

The combined passage of influenza A and B viruses in series, as reported by Sugg and Magill, has been confirmed. When the mixed passage materials were not too highly diluted both agents could be traced through 10 transfers.
Growth curve experiments revealed that both agents developed independently, as measured by hemagglutination-inhibition tests in the presence of specific immune sera against one or the other type. However, the hemagglutinin titers of the 2 viruses in the mixed series were always substantially lower than those recorded when the strains were used individually as seed in the same concentrations as were employed in the mixed series.
Assay of the infectivity titers of the individual strains in the presence of appropriate immune sera led to the demonstration that the time required for the growth cycle of influenza B virus varied with the dose of seed virus. With undiluted infected allantoic fluid as seed only 4 to 5 hours elapsed before new generations of virus were liberated. With increasing 10-fold dilution of the seed the constant period became increasingly longer until it stabilized at 8 to 10 hours. This finding offers an explanation for the seeming discrepancy between the observations on interference between the 2 viruses and the difference reported previously in the extent of their growth periods, on the one hand, and the fact that the 2 agents could be carried simultaneously in series through numerous passages in the chick embryo.
STUDIES ON HOST-VIRUS INTERACTIONS IN THE CHICK EMBRYO-INFLUENZA VIRUS SYSTEM
Authors: Henle Werner , Liu Oscar C. 
Published: June 2004

Evidence has been presented that influenza viruses both of type A and B partially inactivated by ultraviolet irradiation may regain their capacity to propagate in the allantoic membrane of the chick embryo. In using such irradiated preparations as inocula for growth curve experiments it could be shown that the development of hemagglutinins as well as of infectivity preceded at rates resembling those noted with more than 10 times the amount of infective virus actually found in the irradiated seed. Partial inactivation of the inocula by heating to 56°C. gave similar results.
The phenomenon was observed only with seed irradiated for short periods of time so that the virus particles sustained only few hits of radiation. On prolonged exposure resulting in numerous hits per virus particle the capacity of reactivation was lost. Likewise, an irradiated preparation capable of reactivation in the allantoic membrane, could not be diluted more than about 30-fold and still clearly produce this phenomenon. This indicated that reactivation is obtained only when one host cell adsorbs more than one non-infective virus particle but not upon adsorption of a single particle.
These data are in striking agreement with the phenomenon of "multiplicity reactivation" observed in the bacteriophage-E. coli system by Luria and Dulbecco.
AN ELECTROPHORETIC STUDY OF A STREPTOCOCCAL PROTEINASE AND ITS PRECURSOR
Authors: Shedlovsky Theodore , Elliott S. D. 
Published: June 2004

An electrophoretic study of crystalline preparations of a streptococcal proteinase and its precursor established their isoelectric points at pH values of 8.42 and 7.35 respectively (ionic strength 0.10).
Preparations of the proteinase appeared to be electrophoretically homogeneous over a pH range of 5 to 8.5. Precursor preparations contained a relatively low concentration of the active enzyme visible as a separate peak in electrophoretic patterns of sufficiently concentrated solutions.
Autocatalytic conversion of precursor to active enzyme was complete and resulted in a corresponding change in the electrophoretic pattern.
Treatment of precursor preparations with trypsin produced incomplete conversion to the active enzyme and resulted in the formation of a modified precursor protein. This differed from the parent substance in electrophoretic mobility and in susceptibility to trypsin, but resembled it in immunological specificity and, as previously shown, in susceptibility to conversion to active enzyme by autocatalysis.
Serological reactions of precursor and active enzyme components withdrawn from the cell after electrophoresis are described. It appears that the precursor protein may have two antigenic groups, one specific, the other shared by the active enzyme which behaves as a single antigen.
THE EFFECT OF ADRENOCORTICOTROPIC HORMONE ON INFLAMMATION DUE TO TUBERCULIN HYPERSENSITIVITY AND TURPENTINE AND ON CIRCULATING ANTIBODY LEVELS
Authors: Osgood Charles K. , Favour Cutting B. 
Published: June 2004

The treatment with adrenocorticotropic hormone of guinea pigs sensitized with heat-killed tubercle bacilli caused suppression of their skin reactivity to tuberculin. Similar animals treated with saline did not show this change.
Normal guinea pigs treated with adrenocorticotropic hormone showed suppression of inflammation, but not necrosis, produced by intracutaneous oil of turpentine. There was slight, but probably not significant, diminution of inflammation during saline administration.
Tuberculin complement-fixing antibody titers were not altered by either adrenocorticotropic hormone or saline administration.
Adrenocorticotropic hormone produced marked eosinopenia and lymphopenia in guinea pigs.
THE DOMINANT ROLE OF THE LIVER IN PLASMA PROTEIN SYNTHESIS
Authors: Miller L. L. , Bly C. G. , Watson M. L. , Bale W. F. 
Published: June 2004

A direct study of the isolated rat liver perfused with oxygenated blood containing amino acids and lysine-ϵ-C14 has yielded facts indicating that the liver synthesizes practically all the plasma fibrinogen, the albumin fraction, and probably more than 80 per cent of the plasma globulin fraction.
The response of the isolated perfused liver in protein synthesis is qualitatively and quantitatively analogous to that of the intact animal, notably in (a) the ability to discriminate between natural L-lysine and D-lysine, (b) the per cent of isotopic amino acid converted to CO2, (c) the per cent utilized in liver and plasma protein synthesis.
The results obtained with the perfused liver are compared and contrasted with those reported for tissue homogenates, minces, and slices.
STUDIES ON ENTRY AND EGRESS OF POLIOMYELITIC INFECTION
Authors: Faber Harold K. , Silverberg Rosalie J. , Dong Luther 
Published: June 2004

Within 48 hours after simple oropharyngeal exposures of cynomolgus monkeys to poliomyelitis virus, histological signs of infection were found in ganglia supplying the exposed mucous membranes. At 3 days, virus was found in the Gasserian, petrosal-nodose, and superior cervical sympathetic ganglia. Lesions were most extensive and severe in the Gasserian. Virus continued to be detected daily from the 3rd to the 8th day, inclusive, in the Gasserian but not on the 9th; from the 3rd to the 6th day, inclusive, in the petrosal-nodose but not on the 7th, 8th, or 9th; on the 3rd and 6th days only, in the superior cervical sympathetic; and on the 5th day only, in the celiac.
In all the ganglia examined, the histological signs of infection increased to a maximum on the 5th day, and thereafter declined. In the sympathetic ganglia, a secondary late increase was observed on the 7th day.
During the first 7 days, no signs of infection were found in the CNS in 84 per cent of the animals examined, and in the remainder such lesions as were found were probably not significant. In control animals permitted to survive, the median period before the onset of symptoms of poliomyelitis, when these occurred, was 9 days (range 7 to 16 days), and in the animals with symptoms typical extensive lesions were found in the CNS. In two control animals failing to show symptoms and sacrificed at 26 and 30 days respectively, histological signs of infection were present in the Gasserian and other ganglia but none in the CNS.
THE GROWTH CURVE OF THE LANSING STRAIN OF POLIOMYELITIS VIRUS IN THE CENTRAL NERVOUS SYSTEM OF THE MOUSE
Authors: Ainslie John D. 
Published: June 2004

After intracerebral inoculation of mice with a 10 per cent suspension (approximately 2000 LD50) of the Lansing strain of poliomyelitis virus, the infectivity titer in the brain decreased for approximately 6 hours. It then rose rapidly for 12 to 18 hours to reach titers of over 10–4. The rise in titer in the spinal cord closely paralleled that in the brain for 18 hours, after which the titer surpassed that in the brain by as much as one log. The infectivity titers in the central nervous system of unparalyzed mice remained between 10–3.5 and 10–4.2 for at least 7 days. With the onset of paralysis it was found that the titer was consistently and significantly higher in the spinal cords of paralyzed mice than in their brains or in the brains or cords of unparalyzed mice.
After inoculation of 1 per cent virus suspension the increase in titer occurred about 9 hours later than after the inoculation of 10 per cent virus suspension, and the onset of clinical signs of illness was also delayed. Once the titers began to rise, the rate was the same after the inoculation of either concentration of virus, and the maximal levels reached were the same. With both concentrations of virus, maximal infectivity titers in non-paralyzed mice were reached about 9 hours before the onset of signs of poliomyelitis.
The significance of these findings is discussed.
GROUP A STREPTOCOCCUS POLYSACCHARIDE: STUDIES ON ITS PREPARATION, CHEMICAL COMPOSITION, AND CELLULAR LOCALIZATION AFTER INTRAVENOUS INJECTION INTO MICE
Authors: Schmidt Willard C. 
Published: June 2004

A method was developed for the extraction of the group A streptococcus polysaccharide employing pepsin digestion of ground streptococcal cells. This method did not result in the isolation of polysaccharide with chemical and physical chemical properties different from those exhibited by preparations extracted with hot formamide.
Studies of the chemical composition of this polysaccharide demonstrated it to be composed chiefly of rhamnose and glucosamine monosaccharide units in the approximate ratio of five moles of rhamnose to two moles of glucosamine.
The fate of the polysaccharide after intravenous injection into mice was studied using the fluorescent antibody technique. It was found to be rapidly eliminated by the kidney. The presence of the polysaccharide in the renal tubular epithelial cells during the excretory phase was the only evidence of its cellular localization that could be detected under the conditions of these experiments.
OBSERVATIONS CONCERNING THE PRODUCTION AND EXCRETION OF CHOLESTEROL IN MAMMALS
Authors: Byers Sanford O. , Friedman Meyer 
Published: June 2004

Plasma cholesterol was observed to fall after release of biliary obstruction without any concurrent change in biliary excretion of cholesterol.
Excision of the nerve trunks accompanying the hepatic artery did not change the degree of hypercholesteremia following biliary obstruction.
No significant change in the cholesterol content of hepatic tissue occurred following biliary obstruction.
Animals with gastro-intestinal systems removed exhibited no significant change in plasma cholesterol, whereas those subjected to gastro-intestinal removal plus biliary obstruction exhibited a marked hypercholesteremia.
Anastomosis of the bile duct to the inferior vena cava resulted in a hypercholesteremia similar to that occurring after obstruction of the bile duct.
THE ANTISTREPTOCOCCAL PROPERTY OF MILK
Authors: Wilson Armine T. , Rosenblum Herman 
Published: June 2004

Lactenin is reversibly inactivated by the exclusion of atmospheric oxygen. It is also inactivated by the sulfur-containing reducing agents cysteine, glutathione, thioglycollic acid, and BAL.
Group A streptococci which have been acted upon by lactenin have been killed, and not merely prevented from multiplying, since they cannot be revived by inactivating lactenin through the addition of a reducing agent.
Thiamine in great excess inactivates lactenin. The mechanism by which it accomplishes this has not been discovered, but it suggests that the mode of action of lactenin may be to deny thiamine to the lactenin-sensitive cell. Lactenin sensitivity is not, however, related to a requirement for exogenous thiamine, nor does lactenin appear to function by binding environmental thiamine in a form unavailable to the sensitive cell.