bluuebunny/crossref_metadata_2025_split huggingface dataset:
STUDIES OF THE MECHANISM OF ACTION OF URETHANE IN INITIATING PULMONARY ADENOMAS IN MICE
Authors: Rogers Stanfield 
Published: June 2004

The process of carcinogenesis following exposure of mice to urethane is demonstrated in the present work to be intimately related to nucleic acid synthesis. Injection of animals with a DNA hydrolysate immediately prior to a single exposure of the animals to urethane markedly reduced the number of pulmonary adenomas initiated. Aminopterin, known to interfere in nucleic acid synthesis (46), potentiated the carcinogenic action of urethane and this potentiation was blocked by injection of a DNA hydrolysate.
Of the components and precursors of nucleic acids the pyrimidine series seemed especially concerned. Alterations in the utilization of oxaloacetate, ureidosuccinic acid, dihydro-orotic acid, orotic acid, cytidylic acid, and thymine appeared to be critical steps in the oncogenic process, following upon the primary disorder of cellular metabolism initiated by the carcinogen. All these substances except oxaloacetate profoundly reduced the number of tumors initiated by urethane. Oxaloacetate potentiated the carcinogenic effect.
When these results are viewed together and in relation to known facts concerning nucleic acid synthesis they provide evidence suggesting that the point of action of the carcinogen is in the pathway of nucleic acid synthesis below orotic acid and perhaps at the level of ureidosuccinic acid.
The potentiating influence of adenine, 4-amino-5-imidazole carboxamide, and aminopterin, the lack of effect of uracil, and the inhibitory influence of thymine together suggest that DNA rather than RNA is the nucleic acid critical to the oncogenic response of mice to urethane.
CELL-FREE TRANSMISSION IN ADULT SWISS MICE OF A DISEASE HAVING THE CHARACTER OF A LEUKEMIA
Authors: Friend Charlotte 
Published: June 2004

A disease with the characteristics of a leukemia has been found to be serially transmissible in adult Swiss mice by means of cell-free filtrates. Thus far, the disease has been transmitted through twenty-six serial passages with filtrates as well as cell suspensions. The agent readily passes through Selas 03, Berkefeld N, and gradocol membrane filters—these last having an average pore size of 220 mµ. Filtrates remain stable when stored for long periods at –70°C. or when lyophilized. Splenic tissue containing the agent, which was subjected to massive doses of x-ray (50,000 r),—far more than sufficient to kill the cells,—show undiminished infectivity. The agent is inactivated by heating to 56°C. for 30 minutes and by exposure to ether or formalin.
The disease can be transmitted to adult Swiss mice or DBA/2 mice, but not to adult PRI, C3H, A, C57B1/6, or F1(C58 x BALB) mice. Intraperitoneal, subcutaneous, intracerebral, and intramuscular injections are all effective.
EFFECT OF NUTRITION ON THE PRODUCTION OF ACUTE DISSEMINATED ENCEPHALOMYELITIS IN MICE
Authors: Schneider Howard A. , Lee Johanna M. , Olitsky Peter K. 
Published: June 2004

The susceptibility of homozygous BSVS mice to acute disseminated encephalomyelitis (ADE) has been found to be nutritionally dependent. On a laboratory stock regimen of commercial fox chow pellets, whole wheat bread, and milk this genotype is 100 per cent susceptible to the disease. On a "synthetic" diet, containing a minimal list of vitamins adequate for growth and maintenance, susceptibility was found to be reduced to 15 per cent. Supplementation of the "synthetic" diet with biotin, folic acid, and vitamin B12 restored susceptibility to a frequency of 70 per cent. Increasing the supplements tenfold had no further effect in restoring susceptibility frequencies to the 100 per cent level.
In the restoration of susceptibility, folic acid and vitamin B12 were equally effective as single supplements and equivalent to the triple vitamin supplement. The effect of single biotin supplementation was less.
An outbreak of fatal pasteurellosis among BSVS mice latently infected with Pasteurella and used in an ADE susceptibility test has been described. The fatal pasteurellosis has been ascribed to a constellation of determinants including (a) diet, (b) sex, (c) inoculation events, and (d) latent infection with Pasteurella. With males the susceptible sex it was possible to avert the fatal pasteurellosis and continue the nutritional experiments by using females exclusively.
THE LEECH AS A POTENTIAL VIRUS RESERVOIR
Authors: Shope Richard E. 
Published: June 2004

Leeches, fed on swine infected with hog cholera, contained virus for as long as 87 days after their infective blood meals. In three instances, infected leeches apparently transmitted hog cholera virus to susceptible swine in the process of normal feeding.
Myxoma virus persisted in leeches for as long as 154 days after the ingestion of a blood meal from rabbits with myxomatosis.
Leeches fed consecutively, first on swine with hog cholera, and later on rabbits with myxomatosis, acquired both viruses. In such dually infected leeches, the hog cholera virus persisted for as long as 122 days and the myxoma virus for as long as 110 days, the longest periods tested.
Leeches fed consecutively, first on rabbits with myxomatosis, and later on swine with hog cholera, acquired only the myxoma virus. Hog cholera virus could not be demonstrated in such dually fed leeches.
Myxoma and hog cholera viruses appeared to be present in about equivalent amounts in the anterior and posterior thirds of the bodies of infected leeches.
Myxoma and hog cholera viruses were present in the bloody gut contents of infected leeches but were not demonstrable in the body tissues of these leeches.
It seems from the findings presented that leeches are not biological carriers of either myxoma or hog cholera virus but instead carry these two agents mechanically in their gastrointestinal tracts. In doing this, they appear to protect the viruses from various deleterious chemical and physical influences to which they would have been exposed in the open.
It is speculated that leeches could play a role in nature in perpetuating the blood-borne viruses of certain diseases in which close association with bodies of fresh water is of epidemiological importance.
THE LEUKOTOXIC ACTION OF STREPTOCOCCI
Authors: Wilson Armine T. 
Published: June 2004

Following phagocytosis of certain streptococci human neutrophils undergo a rapid disintegration: the leukotoxic reaction. Monocytes and eosinophils are similarly injured, as are polymorphonuclear cells of rabbit and guinea pig blood.
The leukotoxic injury is not produced by culture filtrates of leukotoxic cocci nor does it follow phagocytosis of heat-killed cocci. The leukotoxic effect does not appear to be due to action of any presently known streptococcal product.
The distribution of leukotoxicity among streptococci is not random, for it was found in all strains tested of certain types of group A (6, 12), and was absent from almost all strains of other types (5, 14, 30). Still other types (3, 4) had both leukotoxic and non-leukotoxic representatives. The injury was also produced by some group C and G strains.
Often the streptococci that cause leukocyte death remain alive and proliferate in the cellular debris, but sometimes they are injured by the phagocyte before the latter disintegrates and are unable to proliferate on the slides. The capacity of a strain of streptococcus to injure leukocytes does not necessarily confer virulence on it. This is thought to be because a chain of streptococci, having survived its sojourn in a leukocyte it has killed, is still susceptible to phagocytosis by a fresh leukocyte, and serial phagocytoses may continue until the chain has been exposed sufficiently to the unfavorable intracellular environment to be, itself, killed.
Whether leukotoxicity plays a role in naturally occurring streptococcal disease is unknown. The high incidence of leukotoxicity in Type 12 strains suggested that it might be involved in acute hemorrhagic nephritis, but if so there must be other factors since leukotoxic strains are present in types and groups not now known to be associated with nephritis.
STUDIES ON RENAL JUXTAGLOMERULAR CELLS
Authors: Hartroft Phyllis M. 
Published: June 2004

Hypertension in rats produced by constriction of one renal artery was associated with degranulation of juxtaglomerular cells in the contralateral, undamped, kidney. These findings are consistent with those of other investigators. Furthermore, the degree of granulation (JGI) in the unclamped kidney was inversely correlated with the level of blood pressure (r = –0.7).
Degranulation of JG cells also occurred in rats made hypertensive by application of a "figure-of-eight" ligature to one kidney and removal of the other one, except when the interference in blood supply was so severe that scarring resulted. In these damaged areas, granules persisted or increased in number even though they were decreased in adjacent relatively normal areas.
Occlusion of one ureter in rats produced severe hydronephrosis in the homolateral kidney and an elevation in blood pressure. Juxtaglomerular cell granules persisted in the hydronephrotic kidney but were decreased in the contralateral one. This finding confirmed the results of the above experiments.
Unilateral nephrectomy in comparable rats had no effect on the degree of granulation of JG cells in the remaining kidney or on the level of blood pressure under the conditions of these experiments. The possibility that degranulation of JG cells in the contralateral kidney in the rats described above was due to compensatory hypertrophy was thereby excluded. An elevation in blood pressure was therefore implicated as an important factor in causing degranulation of juxtaglomerular cells.
BACTERICIDAL ACTIVITY OF RAT LEUCOCYTIC EXTRACTS
Authors: Fishman M. , Silverman M. S. 
Published: June 2004

All extract of polymorphonuclear leucocytes of the rat, prepared by means of ultrasonic vibration, was found to be bactericidal against M. aureus. The bactericidal activity was primarily confined to the mitochondrial fraction of the leucocytes.
The rat leucocyte mitochondrial extract was bactericidal against both Gram-positive (M. aureus, ß-Streptococci, Diplococcus pneumoniae, Corynebacterium diphtheriae) and Gram-negative (Shigella dysenteriae, Salmonella enteritidis, Pasteurella pestis) bacteria. The Gram-positive organisms were more susceptible to the bactericidal activity of the mitochondrial extracts.
EXPERIMENTAL STUDY OF DIPHTHERITIC POLYNEURITIS IN THE RABBIT AND GUINEA PIG
Authors: Waksman Byron H. , Adams Raymond D. , Mansmann Herbert C. 
Published: June 2004

Diphtheritic neuritis was produced in rabbits and guinea pigs by injection of underneutralized toxin-antitoxin mixtures. The disease is a progressive, ataxic paresis related in severity to the dose of injected toxin-antitoxin. Cerebrospinal fluids of rabbits with this disease showed "albuminocytologic dissociation" similar to that found in the same disease in man. Histologically the disease is a progressive demyelination of the peripheral nervous system, un-accompanied by axis cylinder damage or inflammation. It involves the spinal roots and sensory ganglia in the rabbit, the peripheral nerves in the guinea pig. Diphtheritic neuritis can be distinguished from experimental allergic neuritis in the rabbit and guinea pig on both clinical and histological grounds. The rabbit disease is however an excellent model of diphtheritic neuritis in man.
In the animals with diphtheritic neuritis, studied in the present work, there was vigorous production of circulating antitoxin and infrequently complement-fixing antibody to horse serum proteins. No antibody against rabbit spinal cord or sciatic nerve was demonstrated. Skin reactivity to both rabbit nerve suspension and diphtheria toxoid was present at 1 to 2 weeks following inoculation and reached a maximum well before the peak of antitoxin response. These reactions did not seem to be typical delayed reactions. No correlation existed between the development of diphtheritic polyneuritis and any of these immunologic events or the circulating complement level, either in time or in degree. Treatment of rabbits with 400 r whole body irradiation 48 hours before inoculation resulted in severe leukopenia lasting about 3 weeks, delay of antitoxin formation with considerable reduction of peak titers, and some decreased skin reactivity to toxoid. It had no effect on the disease process. It is concluded that diphtheritic polyneuritis is produced by a non-immunologic mechanism, e.g., direct toxicity.
THE ROLE OF A NATURAL ANTIBODY IN THE REJECTION OF MOUSE TUMOR CELLS BY THE CHICK EMBRYO
Authors: Green Howard , Lorincz Allan L. 
Published: June 2004

Cells of the Krebs ascites tumor of mice grow well in the body of the chick embryo until about the 17th day of incubation, when degeneration of the tumor can be seen in tissue sections and viable tumor cells begin to disappear from the internal organs of the embryo.
This death of tumor cells follows the appearance in the chick embryo of serum gamma globulins. Among these are antibodies which can agglutinate the tumor cells in vitro, and destroy their viability. These antibodies occur in the blood without the introduction of any foreign antigen. Their possible origin is discussed.
Small numbers of mouse tumor cells growing in the chick embryo are completely eliminated shortly after the time when antibodies ordinarily become detectable. When the number of cells present is larger, viable cells persist longer, and at still higher cell numbers, the embryo or chick is unable to eliminate the tumor, and is itself killed by it.
Gamma globulins of older birds injected into young chick embryos bearing growing tumor clear the embryonic organs of viable tumor cells.
DIPHOSPHOPYRIDINE NUCLEOTIDASE AS AN EXTRACELLULAR PRODUCT OF STREPTOCOCCAL GROWTH AND ITS POSSIBLE RELATIONSHIP TO LEUKOTOXICITY
Authors: Bernheimer Alan W. , Lazarides Penelope D. , Wilson Armine T. 
Published: June 2004

Among 170 streptococcal strains, there were encountered 98 that yielded culture supernates which caused splitting of diphosphopyridine nucleotide (DPN). All of the latter belonged to Group A, C, or G. Release of DPNase accompanied the growth of diverse antigenic types of Group A streptococci, and data on the frequency of DPNase-producing strains for certain types are given. In contrast, cultures representing 3 species of yeasts and 42 species of bacteria other than streptococci of the Lancefield groups were examined for the presence of DPNase as an extracellular product of growth, but in none of these was the enzyme detected.
Of the Group A streptococci examined, 41 strains had pedigrees suggesting that they were the etiologic agents of acute glomerulonephritis, and 39 of these were found to produce DPNase.
There is an association between capacity of streptococi to form DPNase and capacity to kill leukocytes. A possible mechanism of leukotoxicity is suggested.
ENZYMATIC VARIANTS OF INFLUENZA VIRUS
Authors: Padgett Billie L. , Walker Duard L. 
Published: June 2004

Slowly reacting enzymatic variants of the Lee strain of influenza B virus were isolated by the serial application of a technique which concentrated the fraction of the virus population obtained by slow elution followed by passage of this fraction at high dilution in chicken embryos. The variants were stable upon serial passage in chicken embryos and did not differ significantly from the parent virus in any of the characteristics tested other than those relating to the virus enzyme.
Enzymatically, the variants had a much slower rate of activity on chicken mucoproteins than the parent virus. Their activity was greater at 25°C. than at 37°C. and was much enhanced by calcium ions and depressed by a calcium chelating agent. The enzyme of the variant virus was more labile to heat than that of the parent virus although their hemagglutinins were equally stable. It was estimated that the variants comprised less than 3 per cent of the original population of the Lee strain of influenza B virus particles.
THE PROPERDIN SYSTEM AND IMMUNITY
Authors: Pillemer Louis , Landy Maurice , Shear Murray J. 
Published: June 2004

High molecular weight polysaccharide complexes derived from normal and neoplastic mammalian tissues were found to combine with properdin and to inactivate C'3 in vitro. These polysaccharide preparations were also found to alter properdin levels and non-specific resistance to Gram-negative infection in mice. In these manifestations, the tissue polysaccharides bore a marked resemblance to bacterial lipopolysaccharides.
Some implications of the interactions of tissue polysaccharides and properdin in certain disease states are considered.
IMPAIRMENT OF THE ANTIGENICITY OF A PROTEIN ANTIGEN FOLLOWING ITS INJECTION INTO RABBITS
Authors: McMaster Philip D. , Edwards Joshua L. 
Published: June 2004

The findings presented in this paper indicate that 60 gm. of liver tissue, taken from adult donor rabbits 2 weeks after injecting them with large amounts of bovine γ-globulin, and transferred to the peritoneal cavities of recipient rabbits prepared for a secondary reaction, contain enough of the antigen to induce the formation of detectable amounts of precipitin in the recipient rabbits. On the other hand, liver taken from donors 21 and 28 days after injecting them with the same antigen fails to bring about a similar effect. The findings outlined in the paper suggest that the antigen is degraded after the 2nd week to such an extent that it fails to engender the formation of complete antibody in the recipient animals, although previous work has shown (2–4) that the transfer of liver tissue from similar donor rabbits to mice renders the recipient mice anaphylactically sensitive to the antigen, bovine γ-globulin.
The implications of the findings are discussed.
THE RELATIONSHIP BETWEEN THE VASCULAR MANIFESTATIONS OF SHOCK PRODUCED BY ENDOTOXIN, TRAUMA, AND HEMORRHAGE
Authors: Zweifach Benjamin W. , Benacerraf Baruj , Thomas Lewis ,   With the Technical Assistance of P. Viera
Published: June 2004

In studies designed to establish the interrelationship between bacterial endotoxins and the vascular sequelae of hemorrhagic and traumatic shock, the effect of factors known to influence the phagocytic behavior of the reticulo-endothelial system (RES) were investigated.
Measures which induced a so called "blockade" of the RES were uniformly associated with an exacerbation of the vascular effects of the endotoxin of E. coli. Such pretreatment also counteracted the cross-tolerance induced by endotoxins against the lethal effects of hemorrhage or drum trauma.
The vascular reactions characteristic of irreversible hemorrhagic shock could be simulated by a combination of pretreatment with carbon or proferrin and the infusion of small doses of E. coli endotoxin.
An increase in the phagocytic activity of the RES, induced by repeated injections of certain colloids, was associated with an enhanced tolerance of shock.
Measurement of carbon clearance values indicated that although an augmented phagocytic capacity was present in rats with induced tolerance to bacterial endotoxins, the development of resistance to trauma was not associated with a comparable change in the phagocytic function of the RES.
DESOXYCORTICOSTERONE-MIMETIC ACTION OF AMMONIATED GLYCYRRHIZIN IN RATS
Authors: Kraus Shirley D. 
Published: June 2004

The desexycorticosterone-mimetic action of ammoniated glycyrrhizin on electrolyte and water metabolism and on pituitary-adrenal function, was demonstrated in rats. Retention of sodium and water was observed in both intact and adrenalectomized rats during 4 hour minerosteroid assays, the degree of retention being a function of log dose. In intact rats, the antidiuretic effect of glycyrrhizin was immediate and cumulative, while retention of sodium appeared only after a latent period and did not increase with time. Adrenalectomized rats, 3 days after the operation, showed a more marked antidiuretic effect than intact rats, but no greater retention of sodium.
Rats receiving glycyrrhizin prior to histamine stress showed a marked decrease in adrenal ascorbic acid depletion, suggesting that glycyrrhizin had suppressed the output of ACTH.
Whether glycyrrhizin acts on the same target organ as desoxycorticosterone in producing sodium and water retention is still an open question. However, the fact that it is capable of producing a pituitary-adrenal inhibition which resembles that of naturally occurring adrenal steroids is further evidence of the strong pharmacological resemblance between glycyrrhizin and desoxycorticosterone.
STUDIES ON PRIMARY ATYPICAL PNEUMONIA
Authors: Liu Chien 
Published: June 2004

By means of fluorescein-labelled antibody, the primary atypical pneumonia virus was found to multiply exclusively in the cytoplasm of the epithelial cells lining the bronchioles and air sacs of developing chick embryos. When 13-day old embryos were inoculated intra-amniotically and incubated at 35°C. for 5 days or longer, over 90 per cent of the inoculated embryos became infected.
Between 1954 and 1956, seven strains of PAP virus were isolated from sputums or nasopharyngeal washings in patients during the acute stage of the PAP infection. One strain of virus was isolated from the frozen lung of a patient who died at Boston in 1943. All eight recently isolated strains and the Mac strain isolated by Eaton et al. in California in 1944 were antigenically closely related if not identical. PAP virus is not related antigenically to agents of psittacosis, Q fever, adenovirus (Types 1 to 6), influenza A or B, or PVM.
FLUORESCENT ANTIBODY DETECTION OF THE ANTIGENS OF THE SHOPE PAPILLOMA VIRUS IN PAPILLOMAS OF THE WILD AND DOMESTIC RABBIT
Authors: Noyes Wilbur Fiske , Mellors Robert C. 
Published: June 2004

The results obtained by a fluorescent antibody study of the Shope papilloma virus in papillomas of the wild and domestic rabbit are presented.
In the wild rabbit papillomas the viral antigens occurred exclusively in the nucleus and were present in the differentiating cells of the keratohyaline layers and in the keratinized layers. The antigens were not present in the deeper proliferating epithelial cells of the papillomas.
The Shope viral antigens were present in very minute amounts in papillomas of the domestic rabbit, as compared with papillomas of the wild rabbit, and were only detected in the superficial keratinized layers.
It is postulated that virus is present in the nuclei of the proliferating cells of the papillomas of the wild and domestic rabbit but exists there in an early stage of development, consisting mainly of nucleic acid and deficient in protein, therefore non-antigenic and not demonstrable by fluorescent antibody. The nucleic acid moiety of the virus may be infective, and the protein component may provide immunologic specificity and serve to preserve transmissibility. The protein-deficient virus can be referred to as masked virus.
FATE OF NON-VIRULENT GROUP A STREPTOCOCCI PHAGOCYTIZED BY HUMAN AND MOUSE NEUTROPHILS
Authors: Wilson Armine T. , Wiley Grove G. , Bruno Pauline 
Published: June 2004

The fate of non-virulent group A streptococci phagocytized in vitro has been investigated by destroying the phagocyte with electric current and observing whether the liberated cocci multiply.
Human and mouse peripheral blood neutrophils quickly injure ingested cocci, the time required to produce 50 per cent non-survival of chains being 8 and 6¾ minutes, respectively.