bluuebunny/crossref_metadata_2025 huggingface dataset:
Occurrence and distribution of sucrose-metabolizing enzymes in oral streptococci
Authors: Chassy B M , Beall J R , Bielawski R M , Porter E V , Donkersloot J A
Published: January 2020

Specific growth rates, growth yields, and the level and cellular distribution of three sucrose-metabolizing enzyme activities were determined for seven oral streptococci (Streptococcus mutans strains E49, BHT, 10449, SL-1, and LM-7, S. sanguis 10558, and S. salivarius 25975). Cultures were grown in a fermentor at pH 6 with either 20 mM glucose or 10 mM sucrose.Generation times varied between 21 and 70 min. Whereas some strains grew 10 to 50% more slowly with sucrose than with glucose, others did not. Growth was always logarithmic, and the growth yields were similar. Glcosyl transferase (EC 2.4.1.5) was largely extracellular; in sucrose cultures it was appreciably lower, but no major shift to a cell-associated form was found. In glucose cultures, the activity varied between 4 and 140 IU per 6-liter culture. The glucan formed was mostly or exclusively water insoluble. Glcosyl transferase was stimulated weakly (60% or less) by various dextrans. Fructosyl transferase (EC 2.4.1.10) was primarily extracellular (except in glucose cultures of S. salivarius) and varied between 0 and 337 IU/culture. In S. salivarius, the extracellular fructosyl transferase was induced by sucrose. In all S. Mutans cultures, the total fructosyl transferase activity was lower after growth with sucrose. All strains had extra- and intracellular invertase (EC 3.2.1.26) activity. Total levels varied between 210 and 3,500 IU/culture. Less extracellular activity was present in sucrose cultures. Only S. salivarius had appreciable activity in the cellular particulate fraction. Invertase activity was significantly higher than the combined glucosyl and fructosyl transferase activities in all cultures.
Lymphocyte populations in acute viral gastroenteritis
Authors: Dolin R , Reichman R C , Fauci A S
Published: January 2020

Viral gastroenteritis was induced in 16 of 24 normal volunteers after oral administration of either the Norwalk or Hawaii agents. Clinical illness lasted for 24 to 48 h and resolved spontaneously. During acute illness, a transient lymphopenia was noted which involved all lymphocyte subpopulations (thymus-and bone marrow-derived, and null cells). No circulating lymphocytotoxins were detected, and the lymphocytes remaining in the circulation responded normally to mitogenic stimuli. The acute lymphopenia occurred at the time that mononuclear cell infiltration of the jejunal mucosa has been noted. These findings are consistent with the occurrence of a redistribution of circulating lymphocytes during acute illness, with accumulation of lymphocytes at the site of infection in the gut.
Inherited resistance to Corynebacterium kutscheri in mice
Authors: Hirst R G , Wallace M E
Published: January 2020

An analysis of the factors responsible for inherited resistance to Corynebacterium kutscheri was undertaken. Various inbred mouse strains were examined; these included the Swiss Lynch and C57Bl/l mice, their F1 and F2 progeny, and the progeny of the F1 backcrossed to each parent strain. Two modes of inherited resistance are described. An examination suggested that resistance as measured by the mean lethal dose of C. kutscheri was under polygenic control and was inherited continuously. However, the efficiency with which C. kutscheri was eliminated by the mononuclear phagocyte cells of the liver over 3 days differed markedly among strains. A genetic analysis of this mononuclear phagocyte microbicidal efficiency (MPME) in Swiss Lynch and C57Bl/6 mice was undertaken. The trait, MPME, was present, but did not segregate, in the F1 progeny or in the progeny of the backcross to the resistant C57Bl/6 parent; this was clear evidence of dominance. Moreover, MPME segregated in a ratio of 1:1 in the progeny of the backcross to the sensitive Swiss Lynch parent and in a ratio of 3:1 in the F2 progeny. It was concluded that MPME was inherited discontinuously and was controlled by a single dominant autosomal gene (or closely linked group); the recessive allele was assigned the gene symbol ack. Linkage experiments showed there to be no association between the ack locus and any of the immune-response genes.
Induction of cellular and humoral immunological responsiveness to a soluble cercarial antigen preparation from Schistosoma mansoni
Authors: Katz S P , Colley D G
Published: January 2020

The development of immunological responsiveness to a soluble cercarial antigenic preparation (CAP) from Schistosoma mansoni was analyzed in inbred CBA/J mice infected with cercariae, one or multiple times, or sensitized using CAP. Repeated exposure to 75 cercariae at three weekly intervals (3X-75) or subcutaneous administration of 20 mug of CAP (CAP/complete Freund adjuvant [CFA]) stimulated the development of specific anti-CAP lymph node cell blastogenesis. The degree of responsiveness was dependent upon the concentration of CAP in the culture system and was optimal in the dose range of 20 to 30 mug of protein of CAP per culture. Animals exposed once to 75 or 225 cercariae or to two sequential weekly infections with 75 cercariae exhibited a minimal response to CAP in comparison to the responsiveness of 3X-75 or CAP/CFA lymph node cells. Assessment of anti-CAP agglutinating antibody by application of a microtiter passive hemagglutination technique revealed that both 3X-75 and CAP/CFA animals possessed low titers of activity. In addition, both 3X-75 and CAP/CFA sera contained reagin-like antibodies to CAP as detected by the heterologous (rat), 72-h latent period, passive cutaneous anaphylaxis technique.
Isolation of skin permeability factors from culture filtrates of Salmonella typhimurium
Authors: Sandefur P D , Peterson J W
Published: January 2020

Engerotoxins isolated from Vibrio cholerae and toxigenic Escherichia coli cause permeability alterations in rabbit skin. Firm induration and erythema are observed within 18 to 24 h, and visualization of the reaction may be enhanced by intravenous injection of Pontamine sky blue dye. Two skin permeability factors (PF) have been found in culture filtrates of Salmonella typhimurium. A rapid acting factor, produced optimally in brain heart infusion broth at 37 degrees C by numerous Salmonella species, has a critical bluing time of 1 h after completion of skin testing. This rapid PF is heat stable at 100 degrees C for at least 4 h and has no associated induration. The delayed factor is heat labile, being completly destroyed within 30 min at 75 degrees C and causes marked duration of the rabbit skin within 18 h that is indistinguishable from the permeability reactions of V. cholerae and E. coli enterotoxins. Induration produced by the delayed PF is observed only after chromatography of the culture filtrate on a Sephadex G-100 column. Thus, the effects of the delayed PF appear to be masked or blocked by an inhibitor-like substance present in crude culture filtrates. Both early and delayed factors are estimated to have a molecular weight of at least 90,000. It is postulated that one or both of these factors may participate in the pathogenesis of Salmonella infections.
Uptake of diphtheria toxin and its fragment A moiety by mammalian cells in culture
Authors: Saelinger C B , Bonventre P F , Ivins B , Straus D
Published: January 2020

Evidence suggesting that diphtheria toxin reaches the cytoplasm of susceptible mammalian cells by two independent mechanisms is presented. A schematic model describing the two processes of toxin entry into the cell is developed. One process of toxin uptake considered to by physiologically significant is passage of the protein toxin through the plasma membrane. This most likely happens by binding of fragment B to receptors on the membrane and by subsequent toxin-membrane interaction so that ultimately fragment A, the enzymatically active moiety, is transported tothe cell interior. This process, which ultimately leads to cessation of protein synthesis and cell death, involves a comparatively small number of toxin molecules. A second mechanism of toxin uptake is by classical pinocytosis. The majority of toxin taken into the cell is accomplished by this process. The fate of toxin taken into HEp-2 cells via pinocytosis is proteolysis by lysosomal enzymes. Thus, such vesicle-bound toxin is ordinarily not expressed biologically. Evidence suggesting that ammonium chloride provides total protection to diphtheria toxin-susceptible cells by preventing entry of toxin by the specific receptor-associated process is also provided; data showing that the ammonium salt immobilizes bound toxin on the plasma membrane of HEp-2 cells are presented. Finally, it is suggested that actively endocytic cells such as guinea pig macrophages interact with toxin in a significantly different manner than do nonphagocytic cells.
Effect of
Aeromonas salmonicida
(Furunculosis) Infection on the Incorporation of [1-
14
C]Acetate into Lipids of Trout Liver
Authors: Shieh H. S.
Published: January 2020

[1-
14
C]acetate is incorporated into lipids more rapidly by liver from
Aeromonas salmonicida
-infected trout than by normal trout liver, both in vitro and in vivo. The increase was, in general, about twofold to less than threefold.
T2 lipopolysaccharide antigen of Salmonella: comparison of the properties of T2 and mucoid forms
Authors: Sarvas M , Malinen M , Nurminen M , Mäkelä P H
Published: January 2020

The T2 form of Salmonella was found to resemble mucoid mutants to some extent by growing as rather slimy colonies, especially at low temperatures. Its sensitivity to rough-specific phages was greatly reduced at low temperature. However, the T2 form did not produce colanic acid. The mucoid mutants of Salmonella studies corresponded to previously described mucoid mutants of Escherichia coli culturally, chemically,and genetically.
Comparison of serological tests for antibody to hepatitis A antigen, using coded specimens from individuals infected with the MS-1 strain of hepatitis A virus
Authors: Dienstag J L , Krugman S , Wong D C , Purcell R H
Published: January 2020

To compare serological tests for antibody to hepatitis A antigen (anti-HA), we tested 15 paired serum specimens, submitted under code, from individuals infected with the MS-1 strain of hepatitis A virus. Immune electron microscopy (IEM), immune adherence hemagglutination (IAHA), and solid-phase radioimmunoassay (RIA) tests for anti-HA were performed with hepatitis A antigen (HA Ag) derived from human stool; results were also compared with previously reported titers determined by IAHA with HA Ag derived from marmoset liver. Antibody titers (IAHA and RIA) and ratings (IEM) determined with stool-derived HA Ag compared favorably, and a seroresponse to HA Ag was detected by all three methods for every serum pair tested. Differences in titers were noted between IAHA tests with liver-derived and with stool-derived HA Ag, but the discrepancies could be accounted for by differences in test technique. The agreement found in this study among the three techniques was quite good and confirms the specificity and sensitivity of tests for anti-HA that are done with stool-derived HA-Ag.
In vitro growth inhibition of mastitis-causing coliform bacteria by bovine apo-lactoferrin and reversal of inhibition by citrate and high concentrations of apo-lactoferin
Authors: Bishop J G , Schanbacher F L , Ferguson L C , Smith K L
Published: January 2020

Bovine apo-lactoferrin (apo-Lf) was added to in vitro cultures of eight strains of coliform bacteria associated with bovine mastitis. As little as 0.02 mg of APO-Lf per ml resulted in marked inhibition of growth of all coliforms. Growth inhibition was lost if saturated Lf or iron plus apo-Lf was added to the synthetic medium. The inhibition of growth increased as the concentration of apo-Lf increased from 0.02 to 0.2 mg/ml for Klebsiella pneumoniae (OARDC-A1), Klebsiella spp. (K1-21), and Aerobacter aerogenes (55-12222) and 2 mg/ml for A. aerogenes (76-2414-1), Escherichia coli (60-Lilly), E. coli (66-S16), and Klebsiella spp. (K6-24). As the concentration of apo-Lf was increased above 0.2 or 2 mg/ml, there was less inhibition of growth except for E. coli (33-C4). Apo-Lf at 20 mg/ml was bactericidal for E. coli (33-C4). Results are compatible with the hypothesis that coliform bacteria respond to low-iron environments by production of iron-sequestering agents that complete effectively with apo-Lf for free iron. Addition of apo-Lf plus citrate resulted in loss of growth inhibition. The molar ratio (citrate to apo-Lf) was found to be more important than the absolute concentration of either component. A ratio of 75 resulted in 50% growth inhibition, whereas ratios of 300 and greater resulted in less than 10% growth inhibition. These results suggest that the ratio of citrate to Lf would be important in evaluating Lf as a nonspecific protective factor of bovine mammary secretions.
Viral spread in the presence of neutralizing antibody: mechanisms of persistence in foamy virus infection
Authors: Hooks J J , Burns W , Hayashi K , Geis S , Notkins A L
Published: January 2020

Several viruses were categorized on the basis of their ability to spread from cell to contiguous cell and form plaques in the presence of antiviral antibody. Herpes simplex virus, cytomegalovirus, and vaccinia, measles, and foamy viruses were able to spread in the presence of neutralizing antibody, whereas coxsackievirus, encephalomyocarditis virus, vesicular stomatitis virus, mumps virus, and simian virus 5 failed to spread. A detailed study of one of these virus groups (simian foamy viruses) suggested that the ability of these viruses to spread from cell to cell in the presence of antiviral antibody, the failure of antiviral antibody and complement to lyse infected cells, and the poor induction and relative resistance of these viruses to the antiviral action of interferon contribute to the persistent nature of this infection.
Blastogenic response of human lymphocytes to oral bacterial antigens: characterization of bacterial sonicates
Authors: Reed M J , Patters M R , Mashimo P A , Genco R J , Levine R J
Published: January 2020

Soluble sonicate supernatant preparations were made from Actinomyces viscosus (ATCC 19246), A. naeslundii (ATCC 12104), two strains of Veillonella alcalescens (strain HV-1 and a human oral isolate), Streptococcus sanguis (ATCC 10556), S. mutans (strain 6715-T2), Bacteroides melaninogenicus (strain K110), and Leptotrichia buccalis (isolated from human dental plaque). These supernatants were characterized with reference to their chemical and antigenic components and their biological activity determined by using in vitro lymphocyte blastogenesis as a measure of the host's cellular immune response. The sonicate supernatant of each bacterium contained protein, neutral sugars, methylpentose, and nucleic acids. Protein was the major component in all except L. buccalis, in which neutral sugars predominated. The antigenic components in each supernatant were detected by using rabbit antisera prepared against the whole bacteria and the sonicate supernatant. The supernatants showed a complex antigenic distribution on immunoelectrophoretic analysis. The supernatants were shown to be antigenic and not mitogenic in nature, since neither cord blood lymphocytes nor all adult lymphocytes were stimulated. The supernatant antigen preparations showed a reproducible, dose-dependent, and kinetic response in vitro, which was similar to that seen with the antigen preparation streptokinase-streptodornase.
Immunological and serological diversity of Neisseria gonorrhoeae: immunotyping of gonococci by cross-protein in guinea pig subcutaneous chambers
Authors: Arko R J , Wong K H , Bullard J C , Logan L C
Published: January 2020

An in vivo typing system for studying the immunological relationship of gonococcal strains was established. Nine gonococcal strains of proven virulence for guinea pig subcutaneous chambers were selected, and these isolates were used to immunize groups of guinea pigs that were subsequently cross-challenged with graduated numbers of gonococci from these isolates. Resistance to infection was determined by culture of fluid from challenged chambers; results were expressed as the median dose, in colony-forming units, of gonococci required to produce infection in each group of immunized guinea pigs. This information was then used to develop immunotypes of gonococci based on the cross-protection results obtained. Four cross-protecting immunotypes were established from the preliminary nine strains tested.
Granulomagenic activity of serologically active glycolipids from Mycobacterium bovis BCG
Authors: Reggiardo Z , Shamsuddin A K
Published: January 2020

The granulomagenic properties of serologically active glycolipids A1, B2, B3, and C isolated from Mycobacterium bovis BCG were studied. Glycolipid A1, dissolved in olive and injected intradermally in guinea pigs, was able to elicit a granulomatous response that seemed to be of the nonallergic type. This granulomagenic activity was quite striking since only 2 mug was necessary to elicit the reaction. The B and C glycolipids were milder granulomagenic agents. Glycolipid A1, dissolved in olive oil and injected intraperitoneally, was toxic for mice. Mice lost weight after the injection of as little as 10 mug of A1, although not even a dose of 100 mug was lethal. Glycolipid A1 failed to immunize mice against aerogenic infection with virulent tubercle bacilli.
Glucosyltransferase production by Streptococcus sanguis 804 (NCTC 10904)
Authors: Beeley J A , Black P M
Published: January 2020

Streptococcus sanguis 804 (NCTC 10904) was grown ih batch culture at constant pH. and the glucosyltransferase activity of the supernatant was assayed over a 40-h growth period. The optimum pH for enzyme production was 7.0 to 7.2. During growth of the culture, three reproducible phases of enzyme activity were observed. The polysaccharides synthesized during each of these phases were characterized as dextran-like glucans by analysis of acid hydrolysates, gas-liquid chromatography, and a specific aggregation technique. The glucans were studied further by infrared spectroscopy, enzymic degradation, and periodate oxidation. Differences in the proportions of alpha-(1 leads to 3)- and alpha-(1 leads to 6)-linkages were observed. The results suggest that glucan synthesis by S. sanguis involves a multienzyme system.
C-type virus protein p30 in blood from inbred mice correlates with their later incidence of leukemia
Authors: Nexø B A , Krog H H
Published: January 2020

The major core protein, p30, of mouse C-type viruses was quantitated radioimmunologically in lymphoid organs and blood from inbred strains of mice. The concentration of p30 in thymus and spleen had a weak and moderate correlation, respectively, to leukemia frequency. In contrast, the concentration of p30 in blood from mice with a high incidence of leukemia (strains AKR and C58) was 100-fold increased at 2 months of age compared with 10 strains with a low incidence of the disease. The SJL mice, which have a high incidence of reticulum cell neoplasms, showed generally elevated, but variable, values. The high concentration in AKR blood developed during the first weeks of life. Approximately one-third of the DBA/2 mice had elevated levels after 4 to 5 months, whereas the values from mice of the 129 strain were low irrespective in their age. The major part of p30 appeared to be associated with the erythrocytes. The concentration of p30 in the blood seems to reflect the presence of replicating virus in mice. It identifies among the inbred strains a high leukemia group one-half year prior to disease.
Virulence of Streptococcus mutans: cariogenicity of S. mutans in adult gnotobiotic rats
Authors: Michalek S M , McGhee J R , Shiota T , Devenyns D
Published: January 2020

Gnotobiotic rats infected with Streptococcus mutant 6715, mutans C211 at 45 days of age on provided a purified diet containing 5% sucrose developed carious lesions on buccal, sulcal, and proximal molar surfaces within 15 days (60 days of age). The level of caries increased significantly (P less than or equal to 0.01) within the next 15 days (by day 75), an extensive decay was observed on all three molar surfaces of 90-day-old infected rats (45 days after challenge). Mutant C211 was previously shown to exhibit increased glucosyltransferase activity and greater adherence and virulence than S. mutans 6715 wild type (wt). Gnotobiotic rats (90 days of age) infected with either S. mutans AHT or S. mutans 6715 (wt) at 45 days of age developed significantly (P less than or equal to 0.01) fewer caries on all molar surfaces than rats of the same age that were infected with S. mutans 6715, mutant C211. The level of plaque increased 2-fold, and the number of viable S. mutans in plaque increased 10-fold between days 60 and 90 in rats infected with S. mutans 6715, mutant C211. Ninety-day-old rats infected with either S. mutans AHT or S. mutans 6715 (wt) had similar levels of plaque and numbers of S. mutans in plaque; however, these values were two- to fourfold lower than those observed in rats of the same age that were infected with S. mutans 6715, mutant C211.
Comparison of the virulence of O:9,12 and O:4,5,12 Salmonella typhimurium his+ transductants for mice
Authors: Lyman M B , Stocker B A , Roantree R J
Published: January 2020

The purpose of these experiments was to determine whether qualitative differences in the O repeat unit of the lipopolysaccharide of pathogenic Salmonella species affected virulence for mice. O:4,5,12 and O:9,12 sister his+ transductants were derived from a virulent Salmonella typhimurium. Fermentation markers were introduced by transduction to differentiate these strains, and the strains were used as mixed challenge to CF1 and C57B1/6J mice. Liver and spleen cultures of the mice of various intervals after challenge indicated that the O:4,5,12 member of the nearly isogenic pair regularly multiplied to a greater extent than the O:9,12 after intraperitoneal challenge for both strains of mice. After oral challenge, there was little difference in the amount of multiplication of the O:4,5,12 and O:9,12 strains in CF1 mice, but the O:4,5,12 was the predominant strain recovered in 8 of 10 instances in the C57B1/6J mice.
Fat of Coxiella burnetti in macrophages from immune guinea pigs
Authors: Kishimoto R A , Veltri B J , Shirey F G , Canonico P G , Walker J S
Published: January 2020

The interaction between Coxiella burnetii and peritoneal macrophages obtained from immune guinea pigs was studied by transmission electron microscopy. Phagocytosis and subsequent fate of ingested phase I and II rickettsiae were compared. Phase I rickettsiae were more resistant to phagocytosis than were phase II organisms. Macrophages from phase I- and II-immunized animals were equally capable of phagocytizing rickettsiae. Phase I and II rickettsiae previously treated with normal serum multiplied and destroyed macrophages from guinea pigs that had been immunized with phase II rickettsiae. Phase II organisms were initially suppressed in macrophages from phase I-immunized animals, but eventually multiplied in these cells. In contrast, only phase I organisms were destroyed by macrophages from phase I-immunized animals. Treatment of rickettsiae with immune serum enhanced ingestion by macrophages and potentiated the destruction of organisms by both types of macrophages. The macrophage migration inhibition assay was performed on peritoneal exudate cells from immune animals. Migration of peritoneal macrophages from phase I-immunized guinea pigs was inhibited, whereas macrophages from phase II-immunized animals migrated when cells were cultured in the presence of killed, intact phase I or II C. burnetii.
Genital inoculation of male baboons with Neisseria gonorrhoeae
Authors: DiGiacomo R F , Gale J L , Holmes K K , Buchanan T M
Published: January 2020

Eight male baboons inoculated intraurethrally with Neisseria gonorrhoeae failed to shed gonococci or develop serum antibody. Urethral inoculation, preceded by epididymal inoculation, elicited an anamnestic antibody response.
Penicillin sensitivity and serum resistance are independent attributes of strains of Neisseria gonorrhoeae causing disseminated gonococcal infection
Authors: Eisenstein B I , Lee T J , Sparling P F
Published: January 2020

We have determined that isolates of Neisseria gonorrhoeae from patients with disseminated gonococcal infection (DGI) are different from randomly collected isolates from patients with uncomplicated (local) disease. Our comparison was based on the six phenotypic properties of: sensitivity to penicillin (PenS), erythromycin, and streptomycin; resistance to the bactericidal effects of pooled human sera; requirements for arginine, hypoxanthine, and uracil (AHU-); and sensitivity to toxic agar. Although the marked association among these traits made analysis difficult, several factors independently related to virulence were defined. The DGI isolates were significnatly more PenS and resistant to serum, even when the other variables were held constant. An apparent correlation between AHU- auxotype and virulence was shown to be due to the PenS property of most AHU- isolates. Thus, certain mutations to antibiotic resistance as well as susceptibility to sera, may result in loss of virulence in the gonococcus, perhaps through alteration of cell envelope structure.
Induction of the synthesis of cell wall alpha-1,3-glucan in the yeastlike form of Paracoccidioides brasiliensis strain IVIC Pb9 by fetal calf serum
Authors: San-Blas G , Vernet D
Published: January 2020

In vitro subculturing of the yeastlike form of Paracoccidioides brasiliensis strain IVIC Pb9 leads to the disappearance of alpha-1,3-glucan as a main component of its cell wall. However, the addition of fetal calf serum to the growth medium induces the synthesis of this polysaccharide. It is suggested that the synthesis of alpha-1,3-glucan in the cell wall of the yeastlike form of P. brasiliensis is induced by external factors.
Role of zinc in the abatement of hepatocellular damage and mortality incidence in endotoxemic rats
Authors: Sobocinski P Z , Powanda M C , Canterbury W J , Machotka S V , Walker R I , Snyder S L
Published: January 2020

Intraperitoneal administration of zinc (ZnIP) as zinc chloride prior to or simultaneously with a lethal quantity of intraperitoneally administered Salmonella typhimurium endotoxin significantly protected rats against toxin-induced mortality and hepatocellular damage. Pretreatment with amounts of zinc chloride ranging from 0.4 to 2.0 mg/100 g of body weight resulted in 80 to 100% survival compared with 10% survival in untreated control rats at 24 h after endotoxin treatment. Zinc chloride treatment in excess of 2.0 mg/100 g of body weight appeared to be toxic and provided diminished protection. In contrast with the protection obtained with ZnIP, intravenously administered zinc did not provide protection. The effectiveness of ZnIP to enhance survival if it was given after endotoxin was greatly diminished as a function of time after endotoxin. The extent of hepatocellular damage was assessed at various times after endotoxin administration in ZnIP-treated and untreated rats by measurement of plasma ornithine carbamoyltransferase activity and histological examination of liver sections. Endotoxin absorption from the peritoneal cavity and hepatic uptake were studied by using 51Cr-labeled endotoxin. ZnIP pretreatment significantly reduced 51Cr-labeled endotoxin content of blood and liver when compared to untreated controls, and effectively prevented endotoxin-induced elevations in plasma ornithine carbamoyltransferase activity and hepatic tissue necrosis. These data indicate that protection afforded by ZnIP treatment results as a consequence of the ability of zinc to diminish absorption of the toxin from the peritoneal cavity and subsequent hepatic uptake.
Development of arthrospores of Trichophyton mentagrophytes
Authors: Bibel D J , Crumrine D A , Yee K , King R D
Published: January 2020

Arthrosporogenesis of the dermatophyte Trichophyton mentagrophytes was examined by light and by scanning and transmission electron microscopy. Sabouraud dextrose agar plates were inoculated with microconidia and incubated in an atmosphere of 8% CO2. Typical germination and hyphal branching continued to day 4, when hyphae began to be increasingly coated with granular-fibrillar material. Multiple replication of nuclei and formation of segregating septa followed. By day 6 the thick surface mesh sometimes was restricted to protruding rings, probably over septa. Between days 6 and 7, after thickening of outer and septal walls, units began to round and separate. Triangular gaps, which developed at the junction of septa and outer wall layers, enlarged so that spores were held together at their poles and along a tangential ring. With elongation of the spore to its barrel shape, the halves of the septum separated and the ring pulled apart, leaving a jagged, circular flange originating from the outer layer of cell wall extended toward the poles, covering the apparently exposed inner wall layer. Newly formed arthrospores, which measured 2.0 to 3.3 by 2.9 to 3.8 micronm and possessed walls of about 0.33-micronm thickness, has smooth sides but somewhat rough poles.
Inhibitory action of galactose on phagocytes from normal and hypergalactosemic chicks
Authors: Litchfield W J , Wells W W
Published: January 2020

The inhibitory effect of galactose on phagocyte function was investigated in normal and hypergalactosemic chicks by monitoring the in vitro killing of Escherichia coli by leukocytes and the in vivo clearance of colloidal 125I-labeled bovine serum albumin ([125I]BSA) from the circulation. Elevated levels of galactose (30 mM) significantly impaired the bactericidal activities of leukocytes from both control and hypergalactosemic chicks. However, the latter cells were more susceptible to the galactose-dependent inhibition. Leukocytes from hypergalactosemic chicks displayed near-normal bactericidal activity when assayed in vitro under simulated normal conditions in the absence of galactose. Mean corrected phagocytic indexes, obtained from data on the clearance of colloidal [125I]BSA, were calculated to be 0.358 and 0.299 for control and hypergalactosemic chicks, respectively. Moreover, increased concentrations of galactose significantly impaired the bactericidal activity of circulating leukocytes but did not significantly affect the phagocytic activity of the reticuoendothelial system.
Release of e antigen from a Dane particle-rich preparation of hepatitis B virus
Authors: Lam K C , Tong M J , Rakela J
Published: January 2020

Tween 80 treatment of a Dana particle-rich pellet obtained from sera of a carrier with a hepatitis type B infection resulted in the release of e antigen.
Identification, separation, and preliminary characterization of invertase and beta-galactosidase in Actinomyces viscosus
Authors: Kiel R A , Tanzer J M , Woodiel F N
Published: January 2020

The initial step of disaccharide dissimilation by Actinomyces viscosus serotype 2 strain M-100 was studied. Sucrase activity was found in the 3,000 X g particulate fraction and the 37,000 X g soluble fraction of the cells, whereas lactase activity was found almost exclusively in the 37,000 X g soluble fraction. Neither sucrase nor lactase activity was appreciable in the culture liquor. Sucrose phosphorylase, alpha-glucosidase, and polysaccharide synthesis activities were not observed in the soluble cell fraction. The sucrase was identified as invertase (EC 3.2.1.26; beta-D-fructofuranoside fructohydrolase). The lactase was identified as beta-galactosidase (EC 3.2.1.23; beta-D-galactoside galactohydrolase). The enzymes in the 37,000 X g soluble fraction were separable by diethylamino-ethyl-cellulose chromatography, giving one beta-galactosidase peak and one major and one minor invertase peak. Acrylamide gel electrophoresis showed different electrophoretic mobilities of the enzymes. The molecular weight of the beta-galactosidase is about 4.2 X 10(5) and that of invertase is about 8.6 X 10(4). The beta-galactosidase has a Km for lactose of about 6 mM and a pH optimum between pH 6.0 and 6.5. The major invertase component has a Km for sucrose of about 71 mM and a pH optimum between pH 5.8 and 6.3.
Antibody response in vitro of spleen cells from Plasmodium yoelii-infected mice
Authors: Brown I N , Watson S R , Sljivić V S
Published: January 2020

The primary antibody response to sheep erythrocytes and dinitrophenylated Ficoll of spleen cells from mice infected with Plasmodium yoelii was studied in vitro. The response to sheep erythrocytes was enhanced between 2 and 4 days after infection and depressed at later intervals. Cell fractionation experiments carried out at the time of immunosuppression indicated a defect of macrophage function. At the same time the response to dinitrophenylated Ficoll was normal.
Human nasal epithelial cell culture system: evaluation of response to human interferons
Authors: Harmon M W , Greenberg S B , Johnson P E , Couch R B
Published: January 2020

This report describes the response of human nasal epithelial cells to exogenously applied human interferon (IF). To measure the response, a system developed to study human nasal epithelial cells in vitro was used. Nasal epithelial cells responded equally to both leukocyte and fibroblast IF, with development of resistance to virus replication that was time and dose dependent. Cells required contact with 1,000 U of IF (400 69/19 reference units) for 4 h to produce consistently a significant reduction in virus yield. This in vitro cell cultured system may be useful in predicting the in vivo response of human IF in respiratory viral infections.
Bacterial lipopolysaccharide induction of a mouse spleen factor stimulating ribonucleic acid polymerase II
Authors: Tsuda M , Mizuno D , Natori S
Published: January 2020

When bacterial lipopolysaccharide, a B-cell mitogen, was injected intraperitoneally into mice, the rate of deoxyribonucleic acid synthesis and the number of antibody-secreting cells in the spleen increased simultaneously, reaching a maximum in 3 days. The rate of ribonucleic acid synthesis also increased during this period, and this was found to be due to activation of alpha-amanitin-sensitive transcription in lymphoid cells of the spleen. The factors stimulating ribonucleic acid polymerase II in the spleens of normal mice and those treated with lipopolysaccharide were compared, and an additional factor besides that present in normal spleens was found in the spleen of lipopolysaccharide-treated mice.
Serological cross-reactivity between group B Streptococcus and Sporothrix schenckii, Ceratocystis species, and Graphium species
Authors: Nakamura Y , Ishizaki H , Wheat R W
Published: January 2020

Serological cross-reactivity of a group B Streptococcus (H36B) with Sporothrix schenckii and 39 different Ceratocystis and Graphium species was investigated by double immunodiffusion. Rabbit anti-H36B serum reacted with antigens from S. schenckii and from 36 of 39 Ceratocystis and Graphium species. It is speculated that low-titer agglutinins to S. schenckii in normal sera are due to antibodies raised against various bacteria which share common antigens with S. schenckii.
Interaction of lipoteichoic acid of group A streptococci with human platelets
Authors: Beachey E H , Chiang T M , Ofek I , Kang A H
Published: January 2020

The interaction of group A streptococcal lipoteichoic acid (LTA) with mammalian cell membranes was studied in human platelets. The binding of LTA to platelets was platelet concentration and time dependent. Binding approached a maximum within 10 min of incubation. The bound LTA could be displaced by adding a 50-fold excess of unlabeled LTA. An association constant of 1.9 X 10(-7) M was calculated, and only one population of binding sites was detected. Immuno-ferritin labeling of LTA-treated platelets demonstrated a patchy distribution of LTA binding sites on the platelet surface. LTA inhibited collagen- and alpha1 chain-induced platelet aggregation, but not the platelet release reaction, suggesting that the LTA and collagen binding sites on human platelets are distinct. Apparently, LTA binds to platelets and interferes with collagen-induced aggregation although collagen is still able to attach to binding sites to trigger the release reaction.
Effect of Staphylococcus aureus delta toxin on Chinese hamster ovary cell morphology and Y-1 adrenal cell morphology and steroidogenesis
Authors: O'Brien A D , Kapral F A
Published: January 2020

Since Staphylococcus aureus delta toxin previously had been shown to increase the cyclic adenosine 3',5'-monophosphate (cAMP) content of guinea pig ileum, the effect of delta toxin on such cAMP-mediated responses as morphogenesis and steroidogenesis in cultured tissue cells was examined. In contrast to cholera toxin, delta toxin did not cause spindling of Chinese hamster ovary cells. Unlike adrenocorticotropin or cholera toxin, delta toxin was unable to cause rounding of Y-1 adrenal cells or to promote steroid production by the cells. S. aureus alpha toxin and enterotoxin B were also unable to cause rounding of Y-1 adrenal cells. Omission of Ca2+ from the media still allowed for increased steroid production by adrenocorticotropin but not by delta toxin. Delta toxin at concentrations greater than 10 micrograms/ml did cause lysis of both Chinese hamster ovary and Y-1 adrenal cells. These findings suggest that the increase in intestinal cAMP levels caused by delta toxin is mediated through a mechanism different from that initiated by cholera toxin.
Correlation between oral toxicity and in vitro stability of Clostridium botulinum type A and B toxins of different molecular sizes
Authors: Sugii S , Ohishi I , Sakaguchi G
Published: January 2020

The in vitro sensitivity to acid and pepsin differed markedly among Clostridium botulinum type A and B toxins of different molecular sizes. The larger the molecular size of the toxin, the higher the resistance to these agents. Tye B derivative toxin was rapidly inactivated, but the progenitor toxins resisted in vitro exposure to rat intestinal juice. The molecular dissociation of the progenitor toxins did not occur in rat intestinal juice of pH 7.0, but did occur in a buffer solution of the same pH. The oral toxicity may depend mostly on the stability of toxin molecules in the stomach and, to a less extent, in the intestine. The present results seem to justify the conclusion that C. botulinum type A and B progenitor toxins with molecular sizes larger than 16S are more potent oral toxins than 12S progenitor toxins.
Factors Regulating Cell Wall Thickening and Intracellular Iodophilic Polysaccharide Storage in
Streptococcus mutans
Authors: Mattingly S. J. , Daneo-Moore L. , Shockman G. D.
Published: January 2020

The effects of a series of different antibiotics on the synthesis and accumulation of deoxyribonucleic acid (DNA), ribonucleic acid (RNA), protein, cell wall peptidoglycan (PG), and intracellular iodophilic polysaccharide (IPS) in
Streptococcus mutans
FA-1 were examined.
d
-Cycloserine, penicillin G, or vancomycin treatment resulted in rapid inhibitions of PG synthesis and a consequent decrease in the relative amount of lysine found in PG fractions. Decreases in culture turbidity, an indicator of gross cellular lysis, were not observed. Secondary inhibitions of the rates and extent of syntheses of DNA, RNA, and protein were observed. With all three inhibitors of PG synthesis, IPS synthesis continued for varying time intervals but, at most, resulted in only relatively small and transient increases in cellular IPS content. Chloramphenicol inhibited protein synthesis but permitted continued synthesis of RNA and PG. After 6 h, the cells contained 42% of their [
3
H] lysine in the PG fraction compared with 25% in exponential-phase cells, a good indication of thickened cell walls. In the presence of chloramphenicol, cellular IPS content increased about 2.5-fold during the first 45 min and then decreased to a level (13%) at 6 h very similar to that of exponential-phase cells (about 10%). Rifampin inhibition of RNA (and, consequently, also protein) synthesis resulted in accumulation of cellular PG and IPS. After 6 h, IPS accounted for 38% of the cellular dry weight, and the cells contained 43% of their lysine in PG. Thus, rifampin-inhibited cells appear to have both thickened walls and a high IPS content. The correlation between inhibition of RNA synthesis and IPS accumulation was confirmed by exposing cultures to rifampin for 60 min and then removing the drug, thus permitting the cells to regrow. Upon removal of rifampin and resumption of RNA synthesis, cellular IPS content rapidly decreased to the level expected for exponentialphase cells.
Effects of Trypan Blue Treatment on the Immune Responses of Mice
Authors: Kripke Margaret L. , Norbury Kenneth C. , Gruys Eilene , Hibbs John B.
Published: January 2020

It has been reported that trypan blue treatment decreases the nonspecific resistance of mice to transplanted tumors and inhibits the in vitro cytotoxic activity of activated macrophages. We wished to determine whether this effect of trypan blue could be due to a selective inhibition of certain macrophage functions or whether it reflected a broader form of immunosuppression. We therefore tested the effects of trypan blue on a variety of immunological responses. Treatment of mice with trypan blue delayed their rejection of skin allografts and transplants of a highly antigenic syngeneic ultraviolet light-induced tumor. Trypan blue treatment of either donor or recipient decreased the local graft-versus-host reaction. Filtration of lymph node cells from trypan blue-treated donors on a nylon wool column before use in the graft-versus-host assay abrogated the depressive effect of trypan blue. A transient reduction in the blastogenic response of spleen cells to concanavalin A and lipopolysaccharide mitogens was observed after a single injection of trypan blue, but the response of lymph node cells was unaffected. The depressed response of splenic lymphocytes was not entirely reversed by removal of adherent cells. The primary and secondary hemagglutinin responses to sheep erythrocytes were unaffected in trypan blue-treated mice, and the proportion and phagocytic activity of thioglycolate-induced peritoneal macrophages were also unaltered. We conclude that treatment of mice with trypan blue selectively inhibits certain macrophage functions but, at high doses, it can also inhibit some lymphocyte activities.
Effect of indomethacin on intestinal water transport in salmonella-infected rhesus monkeys
Authors: Giannella R A , Rout W R , Formal S B
Published: January 2020

Indomethacin, a nonsteroidal anti-inflammatory agent, will abolish salmonella-induced rabbit ileal secretion when given prior to the establishment of infection. In the present study, we assessed whether indomethacin can inhibit salmonella-induced intestinal secretion when administered after infection and net intestinal secretion are well established. A physiological model of salmonellosis, salmonella-infected rhesus monkeys, was used. This model also permitted an examination of the effects of indomethacin in both the small and large intestines. The effect of indomethacin in control monkeys was also studied. Indomethacin caused a striking enhancement of net intestinal water transport in the jejunum,, ileum, and colon of salmonella-infected monkeys. These effects occurred promptly and were of sufficient magnitude in the ileum and colon to cause a reversal in the direction of net transport from net secretion to net absorption. Indomethacin also enhanced net water transport in the jejunum ileum, and colon of normal animals. These data show that indomethacin markedly enhances net intestinal water transport in both the small and large intestines of salmonella-infected monkeys, even when administered after salmonella infection and intestinal secretion are well established. Similar enhancement also occurs in the normal intestine. The mechanism(s) by which indomethacin produces these effects is not known.
Immunization with R mutants of Salmonella minnesota. II. Comparison of the protective effect of immunization with lipid A and the Re mutant
Authors: Bruins S C , Stumacher R , Johns M A , McCabe W R
Published: January 2020

The protective effect of active immunization with Salmonella minnesota Re bacilli or lipid A was assessed in the granulocytopenic rabbit model. Animals were immunized with Re bacilli, lipid A, or Pseudomonas aeruginosa as a nonspecific immunogen. After colonization with one of three enterobacterial strains (two Escherichia coli, one Enterobacter aerogenes), the immunized rabbits as well as controls given saline injections were made leukopenic with nitrogen mustard and monitored for fever, bacteremia, and death. Survival rates were significantly greater in Re-immunized animals than in saline controls or P. aeruginosa-immunized animals. Immunization with lipid A afforded no protection. In addition, rabbits immunized with Re mutant bacilli developed bacteremia less frequently than the others, indicating that antibody to Re may inhibit invasion of the intestinal mucosa as well as protect after bacteremia has developed.
Effect of neonatal gastrointestinal colonization with cross reacting Escherichia coli on anticapsular antibody production and bacteremia in experimental Haemophilus influenzae type b disease of rats
Authors: Myerowitz R L , Norden C W
Published: January 2020

Neonatal gastrointestinal colonization of newborn rats with Escherichia coli 075:K100:H5, cross-reactive with the capsular polysaccharide of Haemophilus influenzae type b, was harmless but failed to stimulated detectable ( greater than 200 ng/ml) serum anticapsular antibodies. Neonatally colonized rats, when challenged at age 13 weeks by intraperitoneal inoculation of H. influenzae b, showed no difference in the frequency, magnitude, or duration of bacteremia or in the postinfection anticapsular antibody response when compared with saline-fed controls. However, neonatally colonized rats challenged at age 4 weeks had a significantly decreased incidence of sustained bacteremia and/or endophthalmitis when compared with controls. This decreased frequency of disease correlated with a significant increase in postinfection serum anticapsular antibodies. Neonatal gastrointestinal colonization with cross-reacting E. coli appears to "prime" the young host to respond to infection with H. influenzae b with an anticapsular antibody response that protects against sustained H. influenzae b bacteremia and its complications.
Immunization with R mutants of Salmonella minnesota. II. Serological response to lipid A and the lipopolysaccharide of Re mutants
Authors: Johns M A , Bruins S C , McCabe W R
Published: January 2020

Rabbits were immunized with Salmonella minnesota Re mutant bacilli or lipid A, and the serological responses were compared. Re lipopolysaccharide and lipid A were found to possess distinct antigenic determinants as measured by hemagglutination, hemolysis, and precipitin techniques. Lipid A preparations from several enterobacterial and non-enterobacterial species were shown to cross-react in agar gel precipitation reactions. In contrast, preparations from bacilli that do not contain glucosamine as an integral part of their lipid A structure did not demonstrate cross-reactivity with enterobacterial lipid A. Antibody to smooth heterologous bacilli present in some antisera prepared against Re bacilli or lipid A was directed specifically against the smooth lipopolysaccharide and not against the Re or lipid A determinants, demonstrating a nonspecific mitogenic response. Precipitation and immunofluorescence tests indicated that the Re determinant was available on smooth bacilli for reactions with specific antisera but that the lipid A determinant was not.