bluuebunny/crossref_metadata_2025_split huggingface dataset:
STUDIES ON THE PATHOGENESIS OF RABIES IN INSECTIVOROUS BATS
Authors: Sulkin S. Edward , Krutzsch Philip H. , Allen Rae , Wallis Craig 
Published: June 2004

Studies on the pathogenesis of rabies in two species of experimentally infected insectivorous Chiroptera, the Mexican free-tailed bat (Tadarida mexicana), a quasi hibernator, and the little brown bat (Myotis lucifugus), a deep hibernator, provided evidence that brown adipose tissue may serve as an extraneural site for storage and multiplication of rabies virus. Although the Mexican free-tailed bat proved to be relatively insusceptible to experimental rabies infection, virus was demonstrated in the brown fat of 22 per cent of those animals shown to be infected by viral assay in white Swiss mice. Rabies infection in this species was most evident 20 to 40 days after intramuscular inoculation of virus. Rabies virus was found to be widely distributed in the little brown myotis 9 to 26 days following inoculation and virus concentrations in some of the tissues approached the level of the stock mouse brain virus suspension used in inoculating these bats. The shorter incubation period and higher virus titers in the tissues assayed reflect the increased susceptibility of Myotis lucifugus as compared with the Mexican free-tailed bat. Virus was demonstrated in the brown fat of 30 per cent of the experimentally infected Myotis.
In the experimentally infected Myotis lucifugus and in the Syrian hamster which is highly susceptible to rabies infection, rabies virus was isolated more frequently from the brown fat than from the salivary gland indicating that in a susceptible host brown adipose tissue may be as frequent a site of viral proliferation as salivary gland.
Since rabies virus was found to persist for long periods of time in the brown fat of experimentally infected bats and was occasionally demonstrated in this tissue alone, it is suggested that brown adipose tissue provides a mechanism by which these animals may serve as reservoirs for this agent in nature. The possibility that similar mechanisms may be involved in the maintenance of other viral agents during interepidemic periods is discussed.
EFFECTS OF BACTERIAL ENDOTOXIN ON METABOLISM
Authors: Berry L. Joe , Smythe Dorothy S. , Young Leona G. 
Published: June 2004

Mice of different strains were protected against the lethal effect of bacterial endotoxin by concurrent injections of cortisone. Either inadequate amounts of cortisone or excessive quantities of endotoxin voided the protection.
Analyses of blood sugar, liver glycogen, muscle glycogen, and total body carbohydrate in the skinned eviscerated carcass were carried out on different strains of mice given endotoxin and/or cortisone. Poisoned animals were virtually depleted of all carbohydrate while mice given cortisone alone had concentrations of carbohydrate from three to four times that of normal mice. Mice given a lethal amount of endotoxin and a protective dose of cortisone had two to three times as much carbohydrate as animals injected with the same amount of endotoxin alone but significantly less than that found in normal mice.
Dibenzyline failed to alter the lethal effect of endotoxin and to reduce the carbohydrate loss that accompanied endotoxin administration.
Endotoxin, at the dosage level employed, lowered the temperature of mice 2°–3°C. during the first hour or two postinjection and the temperature remained essentially unaltered during the next 4 to 5 hours. Loss in body carbohydrate in endotoxin-poisoned mice cannot be explained, therefore, as the result of an elevated metabolic rate accompanying hyperthermia.
Endotoxin prevented the conversion of injected glucose into liver glycogen but not into muscle glycogen.
Mouse liver mitochondria, in the presence of endotoxin, released from ATP approximately the same amount of inorganic phosphate as that released in the presence of dinitrophenol.
AN ENZYME IN MAST CELLS WITH PROPERTIES LIKE CHYMOTRYPSIN
Authors: Benditt Earl P. , Arase Margaret 
Published: June 2004

Mast cells contain an enzyme which hydrolyzes 3-chloroacetoxy-2-naphthoic acid anilide. By using highly purified mast cells isolated by differential centrifugation in high density sucrose solutions we have been able to study this enzymatic activity in more detail.
The enzyme has properties similar to those of chymotrypsin: Chymotrypsin will hydrolyze the histochemical substrate, and the chymotrypsin and mast cell activities with this substrate are similarly inhibited by diisopropylfluorophosphate. The mast cell enzyme is capable of hydrolyzing the N-acetyl esters of tryptophan, tyrosine, and phenylalanine, the relative rates of hydrolysis being similar to those seen with chymotrypsin. A characteristic trypsin substrate, p-toluenesulfonyl arginine methyl ester, is not acted upon by the mast cell enzyme or chymotrypsin. The pH activity curve of the new cell enzyme is similar to that of chymotrypsin as determined with N-acetyl-L-tryptophan ethyl ester as substrate.
STUDIES ON THE RUNTING SYNDROME IN NEWBORN MICE
Authors: Siskind Gregory W. , Thomas Lewis 
Published: June 2004

Runting was produced by homologous spleen or lymph node cell suspensions, but not by isologous spleen or homologous liver or kidney cell suspensions.
The incidence of runting (a) varied with the particular strain combination employed, (b) increased with increased dose of foreign cells, and (c) decreased as the time interval between birth and inoculation with foreign cells was increased.
A focal, coagulative necrotic, liver lesion was described in runted mice.
It was found that viable cells were required to produce the runting syndrome. Frozen-thawed cells, homogenized cells, and the cell-free supernatant of ground spleen suspensions failed to produce runting.
Runted mice were found to have an anemia of variable degree, and white blood cell counts ranging from marked leukopenia to severe leucocytosis. Mice receiving isologous spleen or homologous liver or kidney showed normal red and white blood cell counts.
Isologous spleen cells, given to newborn mice within 30 minutes following injection of homologous spleen cells, conferred significant protection against the runting syndrome. Isologous spleen injected 1 day after the injection of homologous spleen failed to protect. Newborn mice which had received homologous spleen cells were protected from becoming runted by treatment with "anti-cell donor strain" serum. The offspring of mothers which had been immunized against the spleen cell donor's strain failed to become runted when treated with homologous spleen cells.
The data are regarded as compatible with the concept, presented by previous workers, that runting is the result of an immunological reaction of foreign cells against a tolerant host.
SIMULTANEOUS PRODUCTION OF TWO CAPSULAR POLYSACCHARIDES BY PNEUMOCOCCUS
Authors: Austrian Robert , Bernheimer Harriet P. , Smith Evelyn E. B. , Mills George T. 
Published: June 2004

Study of the capsular genome of pneumococcus has shown that it controls a multiplicity of biochemical reactions essential to the synthesis of capsular polysaccharide.
Mutation affecting any one of several biochemical reactions concerned with capsular synthesis may result in loss of capsulation without alteration of other biochemical functions similarly concerned.
Mutations affecting the synthesis of uronic acids are an important cause of loss of capsulation and of virulence by strains of pneumococcus Type I and Type III.
The capsular genome appears to have a specific location in the total genome of the cell, this locus being occupied by the capsular genome of whatever capsular type is expressed by the cell.
Transformation of capsulated or of non-capsulated pneumococci to heterologous capsular type results probably from a genetic exchange followed by the development of a new biosynthetic pathway in the transformed cell. The new capsular genome is transferred to the transformed cell as a single particle of DNA.
Binary capsulation results from the simultaneous presence within the pneumococcal cell of two capsular genomes, one mutated, the other normal. Interaction between the biochemical pathways controlled by the two capsular genomes leads to augmentation of the phenotypic expression of the product controlled by one and to partial suppression of the product determined by the other.
Knowledge of the biochemical basis of binary capsulation can be used to indicate the presence of uronic acid in the capsular polysaccharide of a pneurnococcal type the composition of the capsule of which is unknown.
AUTOANTIBODIES IN HUMAN ULCERATIVE COLITIS
Authors: Broberger Ove , Perlmann Peter 
Published: June 2004

Sera from 30 children, suffering from ulcerative colitis, were examined for the presence of antibodies capable of reacting with antigens of normal human tissue. It was possible to demonstrate that most of the sera contained a precipitating and hemagglutinating factor, reacting with a constituent of human colonic tissue. This constituent was obtained, within 1 hour after death, from colonic tissue of newborn babies who had died without feeding. It could also be prepared from fetal tissue. The antigen can be extracted with phenol-water at 65°C. and seems to be a polysaccharide. The precipitating factor in the sera of the patients behaves electrophoretically as a γ-globulin.
Phenol-water extracts from liver and from kidney also reacted positively with the sera from certain patients. There are indications which suggest that the antigen obtained from these tissues is identical with that from colon.
Sera from 38 healthy children did not give any reactions with the extracts used. In additional controls, the sera of 32 children with various diseases, all of suspected autoimmune origin, were also tested. A few of these reacted positively with the phenol-water extracts from the organs mentioned above. Most likely, the antigen reacting in these cases is different from that reacting with the antibodies in the sera from patients with ulcerative colitis.
The possible role of the antibodies in the pathogenesis of ulcerative colitis and the mechanism of their formation are discussed.
THE ANTICOMPLEMENTARY EFFECT OF KIDNEY TISSUE
Authors: Beeson Paul B. , Rowley D. 
Published: June 2004

In studying the problem of the peculiar susceptibility of the kidney to coliform bacterial infection it was found that kidney tissue, unlike that of other organs, interferes with the ability of normal serum to destroy these organisms.
The effect was attributable to strong anticomplementary activity, 5 to 15 times greater than that of other organs. Inactivation of complement by kidney tissue was found to have characteristics of a chemical reaction, the active principle being heat-labile, non-dialysable, and difficult to separate from tissue particles. Attempts to purify it or to obtain it in a soluble form usually resulted in great loss in activity.
The component of complement affected was the fourth; i.e., that which is characterized by susceptibility to injury by ammonia. Similarities were found to exist between the conditions of ammonia formation and complement inactivation by kidney homogenates, the most notable being enhancement by phosphate and glutamine.
The possibility is suggested that these findings may help to explain the vulnerability of the kidney to certain infections, especially those due to bacteria which are destroyed by the combined action of complement and antibody.
ALTERATIONS IN STATE OF MOLECULAR AGGREGATION OF COLLAGEN INDUCED IN CHICK EMBRYOS BY ß-AMINOPROPIONITRILE (LATHYRUS FACTOR)
Authors: Levene Charles I. , Gross Jerome 
Published: June 2004

The lathyrogenic agents, ß-aminopropionitrile and semicarbizide, when applied to the chorio-allantoic membrane of the chick embryo produced a dramatic increase in fragility of the embryo.
This alteration was not associated with a change in the concentration of collagen, except in aorta, but was accompanied by a sharp increase in the amount of collagen extractible in cold 1 M NaCl from skin, bone, and aorta.
Increase in fragility and extractible collagen began within 3 hours after introduction of the agent and rose steadily for at least 72 hours. Essentially no collagen could be extracted from tissues of normal chick embryos. Both fragility and amount of extractible collagen were dosage- and time-dependent.
It is concluded that the extractible collagen in lathyrism consists of a large proportion of dissolved fibers previously insoluble and formed prior to administration of the agent. The data also suggest that the "lathyritic" collagen in vivo is not in molecular dispersion but in an aggregate or fibrillar form. It is dispersed by cooling.
The extracted collagen could be reconstituted to typical striated fibrils in vitro and the molecule appeared to be normal in the gross, with regard to asymmetry ratio and intramolecular helical structure.
The evidence at hand suggests that at least one of the defects induced by lathyrogenic agents is an interference with the normal intermolecular cross-linking within the collagen fibril.
THE PRESENCE OF PLASMA INHIBITORS DURING THE CRISIS PHENOMENON IN EXPERIMENTAL RELAPSING FEVER (BORRELIA NOVYI)
Authors: Calabi Ornella 
Published: June 2004

The intensity and duration of Borrelia novyi infection in rats depends upon the dose of spirochetes administered. The spirochetemia in response to an inoculum of 1 x 108 spirochetes/kg. characteristically reaches a peak of 4 to 5 million organisms per c.mm. of blood at about 72 hours. Resolution of the primary infection occurs within 48 hours after the peak counts have been observed, with crisis ending at 100 to 120 hours after inoculation.
Treatment of the acute infection, so standardized, by 10 ml./kg. of crisis plasma intraperitoneally delays the onset of the spirochetemia 76 to 140 hours, and reduces the maximal spirochetal count 10–3 to 10–6 that of the unmodified controls. This is evidence that inhibitor is present in the plasma at the time of crisis and plays a role in limiting the primary infection and subsequent relapses. The activity of crisis plasma is not destroyed by freezing, or after storage at 4°C. for 4 days. Fractions I + II + III and IV + V+ VI from crisis plasma, obtained by method 10 of Cohn et al., were also effective in suppressing the acute spirochetemia, but differed in duration and effectiveness. The first of these was about as potent as the undiluted whole plasma, and the second about as potent as plasma diluted 1:4.
STUDIES ON THE PATHOGENESIS OF FEVER
Authors: Collins Robert D. , Wood W. Barry 
Published: June 2004

Study in vitro of the interaction of bacterial endotoxin with rabbit polymorphonuclear leucocytes has resulted in the following findings:
1. Incubation of endotoxin and leucocytes in saline results in: (a) the release of leucocytic pyrogen, and (b) the inactivation of endotoxin.
2. Cell-free extracts of leucocytes also inactivate endotoxin.
3. Incubation of leucocytes in "physiological" saline causes rapid discharge of leucocytic pyrogen. In contrast, relatively little pyrogen is released by leucocytes incubated in fresh serum.
4. The release of leucocytic pyrogen in serum is markedly stimulated by the presence of endotoxin.
5. Leucocytes obtained from tolerant rabbits interact with endotoxin in essentially the same manner as leucocytes from normal rabbits.
The pertinence of these findings to the pathogenesis of fever and to related information concerning human leucocytes has been discussed.
CELLULAR ORIGIN OF RHEUMATOID FACTOR
Authors: Mellors Robert C. , Heimer Ralph , Corcos Josué , Korngold Leonhard 
Published: June 2004

Fluorescein-labelled aggregated human γ-globulin was found to react in precipitin-type tests with serums of individuals with rheumatoid arthritis. This reagent was also highly reactive and specific for the localization of rheumatoid factor in frozen sections of synovial membranes, lymph nodes, and subcutaneous nodules.
In synovial membranes from patients with active rheumatoid arthritis, rheumatoid factor was present in the cytoplasm of plasma cells at various stages of development and maturity. The appearance of the cytoplasm and the occasional presence nearby of extracellular particles suggested the possibility of a secretory process. All other cells were devoid of rheumatoid factor. Some plasma cells contained 7S and/or 19S γ-globulin and many lacked detectable γ-globulin.
In lymph nodes from a patient with active rheumatoid arthritis, rheumatoid factor was present in approximately one in ten germinal centers as well as in internodular plasma cells. The rheumatoid factor was localized in the cytoplasm and the characteristic protoplasmic processes of the germinal-center cells. All other cells were devoid of rheumatoid factor. 7S and/or 19S γ-globulin was demonstrated in approximately eight in ten germinal centers in these lymph nodes.
Plasma cells with rheumatoid factor were also seen on occasion in rheumatoid subcutaneous nodules.
Tissue sections of comparable structure prepared from normal and pathological control material did not contain rheumatoid factor.
Staining for rheumatoid factor was blocked by pretreatment of sections either with unlabelled aggregated human γ-globulin or with rabbit antiserum against 19S human γ-globulin.
EFFECT OF NUTRITION ON THE RESISTANCE OF MICE TO ENDOTOXIN AND ON THE BACTERICIDAL POWER OF THEIR TISSUES
Authors: Dubos Rene J. , Schaedler Russell W. 
Published: June 2004

Mice on inadequate nutritional regimens were found to be more susceptible to various bacterial diseases than mice fed a complete diet containing 15 to 20 per cent casein. The tests of susceptibility included: (a) infections with virulent bacteria; (b) injection of large doses of avirulent coagulase-negative staphylococci; and (c) lethal effects of bacterial endotoxins.
The infection-enhancing effect of nutritional deficiencies could be rendered even more striking by administering the infective inoculum simultaneously with a sublethal dose of endotoxin.
Despite their great susceptibility to infection, malnourished animals retained much of their ability to eliminate bacteria from the blood, liver, spleen, kidneys, and lungs, at least during the early phases of the infectious processes. This was true even when the animals had received endotoxin simultaneously with the infective dose.
The results suggest that under the conditions of the present study, the nutritional state influenced the outcome of infection not primarily by affecting the fate of the pathogens in vivo, but rather by modifying the ability of the host to resist their toxic effects.
COMPOSITION AND SYNTHESIS OF LIPIDS IN RESTING AND PHAGOCYTIZING LEUKOCYTES
Authors: Elsbach Peter 
Published: June 2004

The lipid content of rabbit polymorphonuclear leukocytes, obtained from peritoneal exudates, constituted 8.7 ± 2.9 per cent of the dry weight of these cells; 60 per cent of all lipids were phospholipids, 20 per cent triglycerides, and the remainder cholesterol and cholesterol esters and a small amount of non-esterified fatty acids (2 to 4 per cent).
The composition of the fatty acids in leukocytes, as determined by gas-liquid chromatography, was slightly different from rabbit serum and red blood cells, but markedly different from the dietary fat.
The synthesis, turnover, and composition of lipids in rabbit leukocytes at rest and during phagocytosis in vitro were compared. Lipid content and composition were not affected by the phagocytic process. However, active phagocytosis resulted in an increase in the rate of turnover of lipids. This stimulation of lipid metabolism was more marked in triglycerides and cholesterol esters than in phospholipids. It is suggested that the increased turnover of lipid during phagocytosis may reflect a general metabolic stimulation accompanying this process, rather than a specific synthesis of phospholipid for the production of new cell membrane.
STUDIES ON FRACTIONS OF METHANOL EXTRACTS OF TUBERCLE BACILLI
Authors: Williams Curtis A. , Dubos Rene J. 
Published: June 2004

Fractionation procedures yielding partially purified vaccine preparations from a 60°C. methanol extract of tubercle bacilli have been described. Some of the preparations have the characteristics of lipopolysaccharides. Certain ones have been found capable of increasing resistance to experimental tuberculosis in albino mice of the Rockefeller Swiss strain. The levels of resistance elicited by these preparations are equivalent to those following vaccination with BCG (Phipps) in this strain of mice as reported by other authors. The admixture of two of the crude fractions in amounts as small as 0.05 mg. each per dose per mouse affords an even greater increase in resistance. Neither of these substances alone in larger doses can approach this degree of efficacy in mouse protection experiments.
The protective activity appears to involve the stimulation of two supplementary mechanisms, one providing a peak resistance between 1 and 3 weeks post vaccination but falling off to a lower level thereafter, the other not responding fully until approximately 6 weeks but continuing undiminished through a 12 week post-vaccination period. The first of these peaks corresponds to an increase in resistance against staphylococci as well as tubercle bacilli. The possibility that the term "broad specificity," rather than "non-specificity," might best describe this phenomenon permits the implication of classical immune mechanisms.
THE ROLE OF OPSONINS IN NON-SPECIFIC IMMUNITY
Authors: Rowley Derrick 
Published: June 2004

A study of the recoveries of radioactivity, and of viable bacteria following injection of P32-labelled E. coli into the mouse peritoneum, has indicated that the rapid decrease in viable bacteria which occurs is largely due to peritoneal events, and not to the transport of bacteria elsewhere.
The serum from mice given lipopolysaccharides 48 hours previously, when used to pretreat bacteria before intraperitoneal injection, was found to stimulate phagocytosis to a greater extent than did pretreatment with normal serum. In addition, macrophages themselves were found to be affected by contact with lipopolysaccharides, either in vivo or in vitro in such a way as to promote their phagocytic abilities. It is suggested that the provocation of non-specific immunity by bacterial lipopolysaccharides involves two facets at least; firstly, an increase in the opsonic capacity of the serum, and secondly an increase in the inherent capacity of phagocytic cells to perform this function.