[Epidemiological study on streptococcal infectious diseases and group A streptococci in Akita: classification of 21 serotypes of group A streptococci (author's transl)].
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Biomedical subjects
Publications and source records attributed to N Ishida.
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One strain of human rotavirus subgroup 1 (KUN) and one strain of subgroup 2 (MO) were isolated with the MA104 cell line, a fetal rhesus monkey kidney cell line. Their subgroup specificities and RNA patterns were identical to those of rotaviruses present in stools before cultivation. Distinct cytopathic effects consisting of obscure cell boundaries, cell fusion, cell rounding, cell detachment, and lytic foci were recognized at passage 3 of MO and passage 6 of KUN. No differences in cytopathic changes were found between the two isolates.
Cold-reactive lymphocytotoxic antibodies (LCA) were investigated in sera from patients with multiple sclerosis (MS) in relation to disease activity. When a serum with more than 20% cytotoxicity is considered positive for the presence of LCA, the positive frequency at remission was 21% (6/28), but at exacerbation it was 83% (10/12). All the sera from normal controls were negative. The average of cytotoxicity expressed as a % killing of target cells by sera at remission was 13%; on the other hand, at exacerbation it was 39%. These results showed that in multiple sclerosis the level of LCA was not persistently high, but increased correlating with the disease activity. From these findings and previous experiments of rescue of measles virus antigens, it was suggested that multiple sclerosis is likely a virus-induced autoimmune disease.
Pigs in Miyagi Prefecture, Japan were examined for swine (Hssw1N1) and Hong Kong (H3N2) influenza virus infection by serological tests. The results obtained revealed that a swine influenza was prevalent with relatively high positive ratios throughout that time, and that the Hong Kong influenza virus closely related to a recent human epidemic strain, A/Yamanashi/2/77, also persisted, corresponding to a human endemic. These epidemiological findings strongly suggested the possibility of direct transmission of Hong Kong virus from humans to pigs and vice versa.
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After oral administration of an organic germanium compound, Ge-132 (300 mg/kg), a significant level of interferon (IFN) activity was detected in the sera of mice at 20 hr and it reached a maximum of 320 U/ml at 24 hr. This IFN activity was lost after heat- or acid-treatment, suggesting that the induced IFN is of gamma nature. The molecular weight of this IFN was estimated to be 19,000 daltons by gel filtration. After the oral administration of Ge-132, NK activity of spleen cells had increased at 24 hr and cytotoxic macrophages were induced in the peritoneal cavity at 48 hr. In mice, receiving intraperitoneal (i.p.) injections of trypan blue or carrageenan 2 days before oral administration of Ge-132, neither induction of IFN nor augmentation of NK activity followed. X ray irradiation of mice also rendered the mice incapable of producing IFN, all suggesting that both macrophages and lymphocytes are required for this IFN induction. After i.p. administration of induced IFN, both NK and cytotoxic macrophage activities appeared at 48 hr with as little as 20 U/ml titered IFN. These facts may indicate that the augmentation of NK and activation of macrophages in mice after oral administration of Ge-132 is mediated by induced IFN.
The antitumor effect of TH69, a lyophilized whole cell preparation of Streptococcus faecalis, was examined in mice using four experimental tumors: Ehrlich carcinoma and sarcoma-180 in DDI mice, MCA tumor in syngeneic C3H mice and Meth-A tumor in syngeneic BALB/c mice. Consecutive intraperitoneal injections of TH69 started one day after the tumor implantation markedly inhibited the growth of the two allogeneic ascites tumors and two syngeneic solid tumors. However, even with the most sensitive Ehrlich ascites tumor, TH69 was ineffective when the tumor cell inoculum was more than 2 X 10(6) cells per mouse. Neither oral nor subcutaneous administrations of TH69 produced significant antitumor effects. After a single intraperitoneal administration of TH69 (300 mg/kg) to mice, interferon was induced in the serum with a titer of 220 U/ml at 14 hr after administration. As TH69 has no direct cytotoxic activity against Ehrlich tumor cells, the antitumor effect of TH69 in mice must be ascribed to some immunopotentiating activity including interferon induction.
Recent findings that OK-432 induces IFN gamma both in vivo and in vitro prompted us to examine the host-mediated antitumor effects of OK-432 previously observed, such as activation of cytotoxic macrophages and augmentation of NK cell activity, through the action of induced IFN. By using partially purified IFN gamma produced in vitro with mouse spleen cells in the presence of OK-432, antitumor effects were examined against Meth-A cells both in vivo and in vitro. Repeated intratumoral injections of IFN gamma (300 U/mouse) resulted in 75% inhibition of tumor growth. In vitro studies also showed that 50 U/ml was enough to inhibit the growth of Meth-A cells. Augmentation of NK cell activity was found both in vivo by a single i.p. injection of 200 U/mouse, and in vitro, with as low a concentration as 5 U/ml. When macrophages obtained from mice after i.p. injection of thioglycolate medium were treated in vitro with OK-432 induced IFN gamma, 20 U/ml was shown to activate the cytotoxic effect of M phi on Meth-A cells. All of the experiments were conducted with a positive control of purified mouse IFN-alpha/beta. With antitumor and cell activating effects compared in units, OK-432 induced IFN gamma was almost 10 times or more as active as IFN alpha/beta.
It was demonstrated that TH69, an lyophylized preparation of streptococcus faecalis TH001 (ATCC No. 31663) induced interferon gamma (IFN gamma) in spleen cell cultures. The IFN activity was found in 8 hrs and reached to the peak of 120-240 U/ml 24-48 hrs after incubation in every concentration of 4, 20, and 100 micrograms/ml of TH69. TH69-induced IFN (TH69-IFN) was produced by T cells assisted by macrophages which were stimulated with TH69, and the activity was neutralized by 80-90% with anti-IFN gamma serum but hardly neutralized with anti-IFN alpha, beta serum. Therefore, TH69-IFN was found to be mostly gamma type. The elution profile of TH69-IFN activity on a column with Toyopearl HW-55S showed that molecular weight of IFN was estimated at 18,000-28,000. Sequential purification on this column of TH69-IFN increased the specific activity to approximately 2.5 X 10(4) U/mg protein (partially purified TH69-IFN: TH69-IFNp). A small amount of TH69-IFNp (5-50 U/ml) augmented NK activity and induced cytotoxic macrophages in vitro. Growth of Meth-A tumor cells exposed to TH69-IFNp of 100 U/ml in vitro declined to 50% and three times injection of TH69-IFN (200 U/50 microliters) into the tumor sites of mice given implants of Meth-A suppressed the tumor growth.
The inhibitory effect of a nonprotein chromophore removed from neocarzinostatin on protein phosphorylation by nuclear protein kinase in vitro has been studied. Low levels of the chromophore greatly inhibited protein phosphorylation in vitro. This inhibition, however, was not selectively dependent on the indicated kinases and their different phosphate acceptors (histones and non-histone protein). In contrast, the protein component (apoprotein) of neocarzinostatin did not affect the phosphorylation even at a concentration of 400-times higher than that of the chromophore. Moreover, apoprotein suppressed the chromophore-induced inhibition of protein phosphorylation in vitro in proportion to the apoprotein concentrations. Kinetic and analytical experiments suggest that the chromophore-induced inhibition of protein phosphorylation seems to be due to the binding of the chromophore to the kinases. In addition, we found that ultraviolet irradiation as well as methanol extraction can release the chromophore from neocarzinostatin, but it exhibits no inhibitory activity of DNA synthesis in growing cells. The fact that the chromophore-induced inhibition of protein phosphorylation in vitro was not sensitive to ultraviolet irradiation, which rapidly inactivated the ability of the chromophore to induce DNA degradation in vitro, suggests that there are different actions involved in the two inhibitions induced by the chromophore which is removed from neocarzinostatin.
Morphogenesis of human rotavirus type 2 Wa strain in MA 104 cells was observed. The virus antigen in the cytoplasm was detected by indirect immunofluorescence twelve hours after infection. The cytopathic effect occurred 24 hours after infection when virus particles were detected by EM in the culture fluid as well as in thin sections of the infected cells. Virus particles were observed in the dilated RER, nuclear envelope (perinuclear space), viroplasm, and a lysosome-like body. Three types of virus particles were noted: double-shelled particles 75-85 nm in diameter, single-shelled particles 64-68 nm in diameter and electron-dense nucleoids or cores 32-40 nm in diameter. The outer shell of virus particles was acquired by budding through the membrane of the dilated RER. Tubular structures, similar in diameter to the single-shelled particles, were found in the cytoplasm and nucleus of infected MA 104 cells. Bundles of filaments or the leaflet-like inclusion bodies of membrane-bounded bundles of filaments were found in the cytoplasm and seemed to be associated with virus particles.
Antibody responses to influenza virus immunizations were examined among junior high school students. The students received two doses of a commercial split-product vaccine containing influenza A H1N1 during a 2-year period following the first appearance of H1N1 virus in the winter of 1977-78. In haemagglutination-inhibition (HI) tests, the students who had been infected with H1N1 virus in 1977-78 showed a better response and wider cross-reactivity to the drift strain than the students who had not experienced earlier H1N1 influenza infection. Neuraminidase-inhibition (NAI) antibody titres after immunization depended upon a history of natural infection with H1N1 virus, since students not previously infected showed no significant NAI antibody rise after immunization.
Mouse immunoglobulin epsilon chain gene was cloned from DNA of a hybridoma producing anti-dinitrophenyl IgE, which was constructed by fusing a spleen cell of a BALB/c mouse with a variant clone of MOPC21 myeloma (IgG1 producer). Because a given active heavy chain constant region (CH) gene is linked to a heavy chain joining segment (JH) gene at its 5' side, the expressed C epsilon gene of the hybridoma was cloned from a phage library containing partial Sau3A digests of IgE hybridoma DNA by using a J gene fragment as a probe. Among 6 X 10(5) phages screened, five positive clones were obtained and three of them were identified as C epsilon gene clones by restriction mapping, Southern blot hybridization, R-loop formation, and partial nucleotide sequence determination. The determined nucleotide sequence predicted the amino acid sequence which resembles a part of the CH3 domain of human epsilon chain. The deletion profile of the C epsilon gene in various myelomas expressing different CH genes indicates that the C epsilon gene is located between the C gamma 2a and C alpha genes. The linkage (5'-epsilon-alpha-3') was directly confirmed by molecular cloning of the overlapping chromosomal segments from newborn mouse DNA.
Mutants of enterovirus type 71 with respect to plaque size were selected from two American and two Japanese strains, and the antigenic relationship between the mutants was analyzed using immune animal and patients' sera. All four strains were mixtures of m+ (big) and m (minute) plaque mutants that were serologically different from each other. Thus, it appears that selected m+ and m mutants must be used for identification and antigenic analysis of isolates of enterovirus type 71. In patients with hand, foot, and mouth disease, the antibody responses to the m mutants of all four strains were significant, but responses to the m+ mutants were poor or absent. No antibody was detected if the current strain including the m+ mutant was used. Thus, the selected m mutant should be used for serologic diagnosis of infection with enterovirus type 71.
Naturally occurring infection with Korean hemorrhagic fever virus among four families living in rural areas of northern and central Japan was proved by the demonstration of antibody to the virus. Furthermore, Korean hemorrhagic fever virus antigen was detected in the lung tissues of wild rodents captured in the endemic area. These findings indicate the endemic presence of Korean hemorrhagic fever virus on Honshu Island, Japan.
Hepatitis B virus e antigen (HBeAg) derived from liver at autopsy or from the serum of asymptomatic carriers has been characterized. The liver-derived HBeAg consisted of two different molecules, one with a mol. wt. of 30 000 (monomer) and the other with a mol. wt. of 90 000 (trimer), in a ratio of 3:1. Both were free of IgG. The serum-derived HBeAgs were heterogeneous with mol. wt. of 30 000, 90 000, 240 000, 400 000 and 540 000. Among them, the so-called IgG-free HBeAgs consisted almost exclusively of the 30 000 and 90 000 molecular species, in a ratio of 1:9. The serum HBeAg of mol. wt. 90 000 was further differentiated into two molecular species, one trimer and the other associated with albumin. The large mol. wt. HBeAgs (240 000, 400 000 and 540 000) were associated with IgG in ratios of one molecule of HBeAg to one, two or three molecules of IgG respectively. The complete dissociation of the IgG molecule was not achieved by 5 M-urea treatment of such HBeAgs, suggesting that it was bound in an immune complex. A hypothetical model is proposed which describes the heterogeneity of the HBeAgs derived from both the liver and serum, and containing HBeAgs either in a free form or associated with serum IgG.