Biopsy specimens of human gastric mucosa of patients with gastric complaints and subjected to endoscopic examination were cultured microaerobically, and Campylobacter pyloridis was detected in 46 out of 80 cases (57.5%). The organism was found in 13 out of 22 patients with gastritis, 11 out of 16 with gastric ulcer scar, 7 out of 16 with gastric ulcer, 3 out of 9 with gastric polyp, 4 out of 5 with gastric carcinoma, 2 out of 2 with esophagus carcinoma, and 6 out of 9 with other gastric diseases. The isolates were identified as C. pyloridis, demonstrating its characteristic features such as positive for oxidase and catalase, negative for reduction of nitrite and nitrate, positive for urease, no growth at 25C, growth at 37C, not tolerant to 1% glycine, and resistant to nalidixic acid. Positive alkaline phosphatase activity was considered as an additional feature characteristic for the strains of C. pyloridis. The major cellular fatty acids were tetradecanoic acid and 19-carbon-cyclopropane acid. This pattern is unique among Campylobacter species. The survival of the organism for a longer period than 60min at pH 2.5 indicates its significant resistance to acidic environment.

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Mycobacterium avium complex strains previously not exposed to any antituberculosis agents could be divided into two groups according to their susceptibility to rifampicin and ansamycin; one group susceptible to 80μg/ml rifampicin and to 1.25μg/ml ansamycin, and another resistant to these concentrations. In each group, the ratio of the minimal inhibitory concentration of ansamycin against that of rifampicin was greatly different depending on the strain. This naturally occurring resistance to rifampicin and ansamycin was frequently correlated to naturally occurring resistance to ethambutol, kanamycin, enviomycin, kitasamycin, and minocycline, but not correlated to that to isoniazid and sulfadimethoxine. Ansamycin was more active than rifampicin against M. bovis, M. kansasii, M. marinum, M. xenopi, and M. haemophilum.

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Protoplasts of Candida albicans were prepared by digestion with Zymolyase and the effect of aculeacin A, a wall-active antibiotic, on the synthesis of microfibrillar structures by the protoplasts incubated for 5hr in an osmotically stabilized medium was studied using several electron microscopical techniques. Chemical analyses of the protoplasts before and after reversion with or without the antibiotic were also performed. Aculeacin A not only inhibited synthesis of microfibrils mainly composed of alkali-insoluble β-glucan, but also their assembly to form thicker bundles. The antibiotic appeared to have no effect on other wall components constituting the surface structure of reverting protoplasts. These data confirmed our previous postulation that aculeacin A is a specific and potent inhibitor of β-glucan synthesis as well as biogenesis of cell walls including β-glucans in susceptible yeasts.

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Varying levels of cross-reactivity to some mycoplasma species were observed in the sera of patients infected with Mycoplasma pneumoniae and even in normal human sera by enzyme-linked immunosorbent assay (ELISA). The absorption of the patients' sera with M. pneumoniae lysate showed the decrease in ELISA titers not only to M. pneumoniae, but also to other mycoplasma species. These results suggested the existence of cross-reactive antibodies to mycoplasmas in human sera. Cross-reactive antibodies to M. pneumoniae and other mycoplasmas in the patients' sera were also demonstrated by Western blotting technique.

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Mice actively immunized with capsular polysaccharides extracted from capsular type strains A, B, C, and D, determined by the serum-soft agar technique, were protected against lethal infection by homologous strains, but no animals survived infection by heterologous substance immunization even with at high doses. Passive protective antibody in rabbit antisera prepared using these strains was absorbed out only by homologous capsular polysaccharide in mice. These results indicated that resistance was specific for capsular polysaccharide. The substance contained mainly neutral sugar, small amounts of hexosamine, methyl-pentose, and phosphate although these amounts varied depending on the capsular types strains.

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A new medium supplement, NU-SERUM, was evaluated for cultivation of human embryonic lung fibloblasts (HEL) and for propagation and storage of human cytomegalovirus (HCMV). NU-SERUM was comparable to fetal bovine serum (FBS) in promoting rapid growth of HEL if they were seeded at a sufficient density. HCMV replicated quite satisfactorily in HEL cultured with media supplemented with NU-SERUM as well as FBS. Inactivation of HCMV at 37C occurred similarly when the medium contained FBS or NU-SERUM. However, at -70C, HCMV was less stable in NU-SERUM-containing medium than in FBS-containing medium. Sorbitol added to the NU-SERUM-containing medium improved the unstableness of HCMV at -70C, and HCMV was storable with such medium. Thus, NU-SERUM is useful as an alternative to FBS not only for growth of HEL but also for propagation and storage of HCMV.

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Peroxidase-labeled Fab' fragments of rabbit antisera against gp52 (major envelope protein) and A-particles of mammary tumor virus (MTV) were prepared and used for investigation by immunoelectron microscopy of the replication cycle of MTV-specific envelope and core antigens in normal and malignant mammary gland cells of female mice. The specificity of the antisera was proven by absorption tests and lack of reactivity to MTV-free mammary tissues. Periodate-lysine-paraformaldehyde (PLP) fixation sufficiently preserved the antigenicity of gp52, while Zamboni's fixative was useful to preserve the core antigen. Saponin pretreatment was necessary to reveal the intracellular antigen of A particles but had no influence on gp52. In addition to its presence at the envelope of B particles, gp52 was clearly associated with the biomembrane system, including the nuclear membrane, endoplasmic reticulum, Golgi apparatus and plasma membrane independent of the presence of virus particles. In mammary tumors, a significant level of gp52 antigen was often expressed on the entire cell surface membrane. In contrast, it was localized only to the apical plasma membrane in normal mammary gland cells. A particle antigens were confined to the intracytoplasmic A particles, usually visible as clusters, and to the inner part of B particles. These ultrastructural findings support the available biochemical data on the morphogenesis of MTV particles.

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The antitumor activity of lipopolysaccharide (LPS) and radio-detoxified LPS of Vibrio parahaemolyticus was tested against S180 cells in Swiss mice. The toxicity of the LPS was 200 times less than that of Salmonella typhimurium LPS. The V. parahaemolyticus LPS could be detoxified by exposure to gamma radiation. Both LPS and the irradiated LPS exhibited antitumor activity, though the irradiated LPS was less effective than the native LPS. These observations indicated that exposure to gamma radiation caused significant detoxification of V. parahaemolyticus LPS and the detoxified LPS still possessed considerable antitumor activity.

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The effect of lipopolysaccharide (LPS) from Vibrio parahaemolyticus on the biochemical and phagocytic activities of murine peritoneal macrophages was determined. Intraperitoneal treatment with different doses (0.5-25μg) of V. parahaemolyticus LPS markedly increased the cellular RNA content as well as lysosomal enzyme activities of peritoneal macrophages. The treatment also stimulated the phagocytic activities of macrophages. These observations suggest that V. parahaemolyticus LPS causes stimulation of murine peritoneal macrophages.

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An interleukin-2 (IL-2) dependent cell line which could be grown continuously with crude concanavalin A-stimulated rat or mouse spleen cell culture supernatant could not survive for over 48hr in the culture medium supplemented with partially purified or recombinant IL-2. The cell growth was restored by adding another factor obtained from the same crude culture supernatant. This potentiating activity which was physicochemically inseparable from serum albumin was also obtained from the culture medium containing 2-mercaptoethanol (2-ME) and incubated at 37C for 24hr without the spleen cells. By further experiments, it was demonstrated that 2-ME itself had the potentiating activity on the IL-2-dependent proliferation of this cell line and cysteine mediated the activity of 2-ME. The cells could not enter S-phase in the absence of 2-ME even in the presence of IL-2.

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Changes in the lymphocyte subsets of 13 patients with varicella, 5 with hand-foot-and-mouth disease, 4 with scarlet fever, 10 with measles and 20 with Kawasaki disease were examined by immunofluorescent flow cytometric analysis using monoclonal antibodies against lymphocyte cell surface antigens. The results were compared with those of age-matched normal controls. A significant increase in the percentage of Leu-2a positive (Leu-2a⁺) cells was shown during the early convalescence of varicella, scarlet fever and measles. A significant decrease in the percentage of Leu-3a⁺ cells during the acute phase was common to all the diseases examined, and a significant decrease of Leu-4⁺ cells was observed except in measles. As a result, a significant decrease in the Leu-3a⁺/Leu-2a⁺ ratio was common to all the diseases examined during the acute and/or early convalescent phases. Leu-M3⁺ cells increased significantly in varicella, scarlet fever, and Kawasaki disease. HLA-DR⁺ cells increased significantly in varicella and Kawasaki disease. No significant changes in the proportions of Leu-7⁺, Leu-10⁺, and 2H7⁺ cells were found throughout the course of all the diseases examined.

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We have developed a fluorometric enzyme-linked immunosorbent assay for measuring IgE antibody to Dermatophagoides farinae. Polystyrene microplates were coated with proteins extracted from the mites. The IgE antibody which attached to the solid-phase antigen was detected by anti-IgE antibody conjugated with β-galactosidase. Four-methylumbelliferyl-β-D-galactoside was used as the enzyme substrate and the fluorescence intensity of the reaction product was measured. The antibody levels determined by this method well correlated with those determined by the radioallergosorbent test (RAST). This method is simpler and less expensive to carry out than the RAST when dealing with a large number of serum specimens for seroepidemiological studies of asthma and nasal allergy.

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