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S Hamada

Publications and source records attributed to S Hamada.

At least 379 records · Page 21Linked to original sources
PubMed1985

Chemical and immunological characterization of a novel amphipathic antigen from biotype B Streptococcus sanguis.

A new type of amphipathic antigen was extracted from whole cells of Streptococcus sanguis ATCC 10557 (biotype B, serotype II) by the phenol/water method. The extract was treated with nuclease P1, and was applied to a column of Sepharose 6B. Each fraction was checked by passive haemagglutination (PHA) and immunodiffusion tests against anti-10557 serum which was obtained by immunizing rabbits with whole cells of strain ATCC 10557. Strong PHA activity was demonstrated in the first hexose-containing peak (peak 1) eluted near the void volume, while the second hexose-containing peak (peak 2) produced a heavy band against anti-10557 serum in an immunodiffusion test. The third peak (peak 3) which partially overlapped with peak 2 reacted with concanavalin A, but not with the antiserum, in agar gel. Peaks 2 and 3 had no PHA activity. Peak 1 contained only 1% phosphorus, indicating that cells of strain ATCC 10557 possess an amphipathic antigen which differs from the lipoteichoic acids that are common in many Gram-positive bacteria. Peak 1 was a fatty acid-substituted heteropolysaccharide composed of glucose, galactose, mannose, glycerol and fatty acids in a molar ratio of approximately 1.0:1.3:2.7:0.3:1.0. PHA activity was inhibited in the presence of polymerized mannose. Peak 2 was composed of glucose, galactose, rhamnose and N-acetylgalactosamine in a molar ratio of approximately 1.0:1.4:0.8:0.8, which was essentially identical to the serotype II carbohydrate antigen reported previously.

Antigens, Bacterial↗
PubMed1985

Biochemical and immunobiological properties of lipopolysaccharide (LPS) from Bacteroides gingivalis and comparison with LPS from Escherichia coli.

Lipopolysaccharides (LPSs) were isolated from Bacteroides gingivalis and Escherichia coli by the phenol-water and butanol-water procedures. The phenol-water-extracted LPS from B. gingivalis 381 was composed of 46% carbohydrate, 23% hexosamine, 18% fatty acid, and 5% protein. The major component sugars of this preparation were glucose, glucosamine, rhamnose, galactose, galactosamine, and mannose, and their molecular ratio was 1:0.9:0.7:0.6:0.6:0.4, respectively. Neither heptose nor 2-keto-3-deoxyoctonate was detected. The butanol-water-extracted LPS from this strain was composed of 76% glucose, 7% fatty acid, and 13% protein, and it was associated with a number of polypeptides (13 to 56 kilodaltons). The main fatty acid of both LPS preparations was palmitic acid. It was found that biological activities of LPS from B. gingivalis were comparable to those of LPS from E. coli in terms of activation of the clotting enzyme of Limulus amebocyte lysate, mitogenicity, polyclonal B cell activation, and stimulation of interleukin 1 production in BALB/c mice. Furthermore, LPS-nonresponsive C3H/HeJ spleen cells were found to yield good mitogenic responses to both phenol-water-extracted LPS and butanol-water-extracted LPS from B. gingivalis or butanol-water-extracted LPS from E. coli. On the other hand, spleen cells from LPS-responsive C3H/HeN mice responded well to all these LPS preparations.

Amino Acids↗
PubMed1985

Immunoregulation in the rat: ontogeny of B cell responses to types 1, 2, and T-dependent antigens.

The development of rat B cells has been examined in neonatal and adult Fischer rats through the use of type 1 (TNP-Brucella abortus), type 2 (TNP-LPS(Ph), TNP-Ficoll) and T cell-dependent (TD) (SRBC) antigens. In vivo splenic PFC responses to TNP-Brucella abortus could be induced in newborn rats and by 12 days of age had reached adult levels. In contrast, the responses to the type 2 and TD antigens were 30% and 70%, respectively, of the adult levels at 30 days of age. Adoptive transfer of the B cells from neonatal and young rats into irradiated adult hosts demonstrated that the kinetics in the development of responses to these antigens (early for type 1, intermediate for TD, and late for type 2) were not due to limiting accessory cell or T cell help in immature rats. In vitro cultures of purified B cells from neonatal and adult rats were responsive to TNP-BA and TNP-LPS(Ph) but not to TNP-Ficoll and SRBC. However, the addition of spleen cell-derived Con A supernatant to the B cell cultures resulted in responses to all four antigens, which arose as a function of B cell age, with kinetics that were identical to those observed in vivo. Fluorescent staining of B cells from rats of various ages for cell surface IgM and analysis on the fluorescence-activated cell sorter (FACS) revealed that all splenic B cells from rats 4 days of age expressed a relatively high level of sIgM, and that a subpopulation that expressed a relatively low level of sIgM increased with age until it represented approximately 50% of the adult splenic B cells. Challenging Con A supernatant-supplemented cultures of FACS-prepared low sIgM+ and high sIgM+ cells revealed that B cells responsive to TNP-Ficoll were confined to the ontogenically late-arising low sIgM+ subpopulation but that B cells responsive to TNP-BA, TNP-LPS(Ph), and SRBC were present in both subpopulations.

Aging↗
PubMed1985

Immunoregulation in the rat: cellular and molecular requirements for B cell responses to types 1, 2, and T-dependent antigens.

The requirements for primary in vitro plaque-forming cell (PFC) development in cultures of purified rat splenic B cells have been examined. Rat B cells were directly responsive to the type 1 antigen trinitrophenyl-Brucella abortus (TNP-BA), but both T cells and adherent accessory cells were required for B cell responses to the type 2 antigen TNP-Ficoll and the T cell-dependent (TD) antigen sheep erythrocytes (SRBC). However, the cellfree supernatants from concanavalin A-induced spleen cells of rat or mouse origin replaced the requirement for T cells and macrophages, and resulted in PFC development in response to TNP-Ficoll and SRBC and augmented PFC numbers in response to TNP-BA. Culture supernatants from induced murine T cell and macrophage cell lines were used to partially deduce the molecular requirements for the support of PFC development by rat B cells to these three antigens. Supernatants from the EL-4 (EL-4 sup) and B151 K12 (B15 sup) T cell lines augmented TNP-BA responses, suggesting that B cell growth factor II (BCGF-II) mediated this effect. An admixture of purified interleukin 2 (IL 2) and B15 sup supported PFC development to SRBC; indicating that IL 2, BCGF-II, and the T cell-replacing factor in B15 sup (B15-TRF) were sufficient to support this response. In addition, the IL 2 plus B15 sup-supported anti-SRBC PFC response was increased by the addition of an interleukin 1-containing fraction from the supernatant of the macrophage line P388D1. PFC development in response to TNP-Ficoll had the most stringent requirements and only occurred in the presence of EL-4 sup and B15 sup (IL 2, BCGF-I, BCGF-II, EL-TRF, B15-TRF). These data indicate that different cellular and molecular requirements exist for PFC development in response to types 1, 2, and TD antigens by rat B cells.

Animals↗
PubMed1985

Transmission of Streptococcus mutans in some selected families.

The aim of the present study was to determine the source and transmission route of Streptococcus mutans. The frequency of this organism in saliva and plaque samples was compared among fifteen pairs of mothers and their children. The results showed that most of the mothers harboured almost equal or greater levels of S. mutans than their children. Similarities of the distribution of various serotypes and mutacin types were observed between these mothers and their offspring. Samples were also collected from plaque and/or carious lesions of the relatives of the subjects who carried one of the serotypes other than serotype c as the dominant S. mutans. The strains of the same serotypes of S. mutans which possessed similar mutacin patterns were predominantly detected in the siblings and mothers of each subject. However, a similar distribution of S. mutans strains was not clearly observed in other relatives including fathers, aunts, uncles and grandparents.

Adult↗
PubMed1985

Diabetic osteopenia in central Japan.

A large scale study of diabetic osteopenia was conducted in central Japan. The degree of bone mass loss was measured in 1267 diabetic patients and 646 control subjects. Based on six indices obtained by microdensitometry, the bone mass of 21.1% of the diabetic patients was found to be markedly decreased and that of 8.2% was found to be severely decreased, while only 7.9% of the control group showed bone mass loss. The prevalence of diabetic osteopenia in female patients was significantly higher than in males, but a positive correlation between the degree of bone mass loss and age was observed in both the male and female patients. Patients requiring oral agents or insulin had significantly more bone mass loss than those on dietary therapy alone.

Adolescent↗
PubMed1985

Longer survival and fewer metastases by levamisole and tegafur in 1, 2-dimethylhydrazine-induced murine colonic cancers.

The anticancer effects of levamisole, tegafur and their combination were experimentally compared in rats on the 1, 2-dimethylhydrazine (DMH)-induced colonic cancers. DMH at 20 mg/kg of body weight was injected subcutaneously to Donryu rats once a week for 24 weeks long. Nineteen weeks after the start of DMH administration, early colonic cancers were induced and, 28 weeks after, they developed into advanced cancers with distant metastases. From 19 weeks after the start of DMH injection, subcutaneous administration of levamisole at the dose of 2 mg/kg, oral administration of tegafur at 90 mg/kg and their combination were given to the rats daily for nine weeks. The animals were sacrificed 28 weeks after the start of DMH administration. Tegafur was effective, but levamisole with or without tegafur was not effective against early cancer. From 28 weeks after the start of DMH injection, levamisole, tegafur and their combination were administered to the rats daily for four weeks. All of the rats were necropsied when they died. The survival rate and mean survival days were significantly higher and longer in the levamisole groups than in the control rats (p less than 0.05). The incidence of distant metastases was also significantly lower in the levamisole groups than in the control group.

1,2-Dimethylhydrazine↗
PubMed1984

Analysis of DNA ploidy patterns of gastric carcinomas of Japanese.

Ploidy patterns of gastric carcinomas of 54 Japanese patients, ranging in age from 28 to 82 years, were determined by cytofluorometry. The gastric cancers were divided into four basic ploidy patterns; the first pattern was a diploid mode, the second was a heteroploid mode, the third was a mosaic pattern of a diploid and a heteroploid mode, and the fourth was a mosaic of two or more different heteroploid modes. The incidence was 68.4%, 14.8%, 12.9%, and 3.7% in the first, second, third, and fourth patterns, respectively. All the cancers contained polyploid populations, whereas the early cancers tended to contain a lesser amount of polyploid cells than the advanced ones. Diffuse-type cancers and well-differentiated, intestinal-type adenocarcinomas were mostly unimodal cancers of the diploidy or heteroploidy, whereas poorly differentiated adenocarcinomas were often mosaic cancers of several different ploidies. There was no correlation between ploidy patterns and ages and sexes of patients. For 11 cases, labeling indices with 3H-thymidine were determined. Labeling indices of the intestinal-type and diffuse-type cancers were 12% to 27% and 7% to 19%, respectively.

Adenocarcinoma↗
PubMed1984

Immunochemical characteristics of Streptococcus mutans serotype h carbohydrate antigen.

Serotype h carbohydrate antigen was prepared from cell walls of Streptococcus mutans strain MFe28 of monkey origin. The h antigen was extracted from the cell walls with 5% trichloracetic acid at 4 C, and purified by DEAE-Sephadex A-25 ion exchange chromatography followed by Sephacryl S-300 gel filtration. The purified antigen was composed of galactose (75%), glucose (16%), and rhamnose (3%). Although the antiserum against whole cells of S. mutans MFe28 gave a strong cross reaction with serotype d S. mutans, serotype h-specific antiserum could be obtained by adequate adsorption. The precipitin reactions and hapten inhibition test using serotype h-specific antiserum showed that galactose, glucose, and their derivative sugars were markedly potent inhibitors. It was concluded that the serotype h antigen is immunologically distinguishable from the known serotypes of S. mutans, although it is closely related to serotype d antigen of S. mutans.

Antigens, Bacterial↗