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51.
Purification and characterization of Staphylococcus aureus FRI 1169 and 587 toxic shock syndrome exotoxins. 总被引:9,自引:6,他引:9 下载免费PDF全文
An exotoxin was purified from a toxic shock toxin (TST)-producing Staphylococcus aureus strain, FRI 1169, and another exotoxin was purified from a pyrogenic exotoxin C (PEC)-producing S. aureus strain, 587. Both strains had been isolated from toxic-shock syndrome patients. The two exotoxins were purified by the same method of ion-exchange chromatography, chromatofocusing, and gel filtration. After purification, those exotoxins gave a line of identity against an anti-TST serum and also were immunologically similar to TST in a double-diffusion test. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis, each exotoxin gave a single band with a relative mobility identical to that of the other. Their molecular weights (24,000), isoelectric points (7.0), amino acid compositions, and NH2-terminal amino acid sequences (the first four residues) were identical. Both produced fever and enhanced host susceptibility to lethal endotoxin shock in rabbits, comparable with PEC. These findings show that the two exotoxins are the same protein, which is assumed to be TST. When injected into rabbits, the culture supernatant of strain 587 showed biological activity like that described above, whereas the culture supernatant neutralized with anti-TST immunoglobulin did not. This showed that PEC-producing strain 587 does not produce any toxin with these biological activities in rabbits except TST. 相似文献
52.
53.
Role of complement in acute tubulointerstitial injury of rats with aminonucleoside nephrosis. 总被引:4,自引:1,他引:4 下载免费PDF全文
A. Nomura Y. Morita S. Maruyama N. Hotta M. Nadai L. Wang T. Hasegawa S. Matsuo 《The American journal of pathology》1997,151(2):539-547
The present work was designed to elucidate the in vivo role of complement in the proteinuria-associated tubulointerstitial injury. Rats were intravenously injected with puromycin aminonucleoside, and massive proteinuria was observed within 5 days. Prominent tubulointerstitial injury characterized by proximal tubular degeneration, tubular dilatation, and leukocyte infiltration were observed 7 days after injection. C3 and C5b-9 were observed in the luminal side of proximal tubular cells. Renal function, assessed by inulin and para-aminohippurate clearance, was significantly decreased. To-assess the role of complement in this model, rats were injected with either cobra venom factor or soluble recombinant human complement receptor type 1 starting at day 3. These manipulations significantly improved tubulointerstitial pathology and para-aminohippurate clearance without affecting the degree of proteinuria. Deposition of C3 and C5b-9 was not detected in the kidney of rats depleted of complement by cobra venom factor. In rats treated with soluble complement receptor, C3 was still detected in the tubules, but deposition of C5b-9 was not observed. Soluble complement receptor was detected at the site of C3 deposition and in the urine. These data strongly suggest that complement plays a pivotal role in proteinuria-associated tubulointerstitial injury and that systemic complement depletion or inhibition of complement in the tubular lumen may diminish the tubulointerstitial damage. 相似文献
54.
M Yamaguchi K Hirai Y Morita T Takaishi K Ohta S Suzuki K Motoyoshi O Kawanami K Ito 《International archives of allergy and immunology》1992,97(4):322-329
Human basophils were purified from normal peripheral blood, using density gradient followed by negative panning selection. We tested the effects of hemopoietic growth factors on the survival of these basophils in vitro. In the absence of exogenous factors, basophils (purity greater than 90%) decreased in number rapidly. At day 7 only 11% of the cells remained alive in cultures; less than 1% of cells survived at day 14. Interleukin (IL)-3 maintained numbers of viable cells; cell viability was 67% at day 7 and 45% at day 14. Granulocyte-macrophage (GM)-colony-stimulating factor (CSF) exhibited slight effect on the survival; 33% of cells remained at day 7. Other growth factors including granulocyte (G)-CSF, macrophage (M)-CSF, and IL-4 had no significant effect on the survival of basophils at all. Morphological and functional characterization of cells maintained by IL-3 revealed that they belonged to the basophil lineage. These observations indicate that normal basophils possess functional receptors for IL-3 and GM-CSF and that both factors modulate immediate- and delayed-type hypersensitivity reactions by prolonging the life span of basophils. 相似文献
55.
Histochemical, immunohistochemical and ultrastructural investigations of giant cell tumors of bone 总被引:1,自引:0,他引:1
The origin and characteristics of so-called stromal cells (stromal cell) and the osteoclast-like giant cell series of 19 cases of giant cell tumor (G.C.T.) of bone were studied. Immunohistochemically, two interesting cases were found. The stromal cells of one case were alpha-1-antitrypsin positive and those of the other case were alpha-1-antichymotrypsin positive. The histiocytic stromal cells of the latter case seemed to be surely neoplastic since they showed mild to moderate cell atypism. There were foci consisting of fibroblastic cells or osteoid and osteoblasts within the tumor. Those cells in the foci were apparently continuous with the surrounding stromal cells, and they were, therefore, also considered to be neoplastic. These findings strongly indicate that the stromal cells originate from the undifferentiated mesenchymal cells in the bone marrow and may differentiate to osteoblastic, fibroblastic, and histiocytic cells. All cells of these three series were not stained for a high stable form of acid phosphatase (SAPhase). SAPhase activity was demonstrated only in osteoclast-like giant cells and some mononuclear cells, which are recently believed to be non-neoplastic. Therefore, the cell atypia of SAPhase negative stromal cells is considered to have a prognostic value. 相似文献
56.
Nishiya K Chikazawa H Matsumori A Chijiwa T Tahara K Morita T Hosokawa T Ito H Hashimoto K Fujieda M 《Rinsho byori. The Japanese journal of clinical pathology》1999,47(2):185-187
Antineutrophil cytoplasmic antibodies (ANCA) for two antigens, i.e. myeloperoxidase (MPO) and lactoferrin (LF) in sera from 19 IgA nephropathy (IgAN), 3 adult Henoch-Sch?nlein purpura (HSP) and 8 child HSP patients were examined by enzyme-linked immunoabsorbent assay (ELISA) for immunoglobulin isotypes. All of child HSP patients showed negative ANCA. On the other hand, one IgAN patient and two adult HSP patients showed weak positivity for IgA class anti-MPO antibody. There was no patients who showed positivity for IgG and IgM class anti-MPO antibody. In anti-LF antibody, one IgAN and one adult HSP showed positivity in IgG class; 2 IgAN and 2 HSP in IgA class and 2 IgAN and one HSP in IgM class. These results indicate that adult HSP patients have higher prevalence of IgA class anti-MPO antibody and anti-LF antibody than IgAN or child HSP. 相似文献
57.
Cloning and characterization of the cDNA encoding the HA protein of a hemagglutination-defective measles virus strain 总被引:3,自引:0,他引:3
Hiroyuki Saito Hiroyasu Sato Mariko Abe Seizaburo Harata Ken-Ichi Amano Tsunehisa Suto Morihiro Morita 《Virus genes》1994,8(1):107-113
cDNA clones corresponding to the mRNA for the hemagglutinin of the hemagglutination-defective strain AK-1 of measles virus were isolated and characterized. Compared with the prototype Edmonstron strain, 60 nucleotide substitutions that resulted in 18 amino acid changes were detected. An additional potential N-linked glycosylation site was added by point mutation, which was supported by the observation that the hemagglutinin of the AK-1 strain was stained more heavily after NaDodSO4PAGE and periodic acid-Schiff (PAS) staining than the Edmonston strain. Computer-assisted analysis revealed that three reverse turns in the secondary structure had disappeared in the hemagglutinin of the AK-1 strain. Moreover, one of these structural changes occurred in the closely glycosylated region at amino acid residues 168–240, which appeared to be a biologically important functional domain. The isoelectric point calculated from the predicted amino acid sequence became about 1 pH unit more basic in the AK-1 strain than the Edmonston strain. This present study is the first sequence analysis of the hemagglutinin gene in a hemagglutination-defective strain of the measles virus. 相似文献
58.
Four hundred and sixty-five male and 159 female consecutive autopsy cases of lung cancer, autopsied over the 27 years from 1958 to 1984, were analysed and were compared with other materials and mortality statistics, including statistics from other countries. Malignant tumor autopsy cases are gradually increasing and now comprise more than 60% of total autopsy cases. The percentage of lung cancer cases among all autopsy cases was 7% in males and 4% in females. The percentage of lung cancer in autopsies of patients with malignancies was about 13% for males and 9% for females. The most frequent fatal malignant tumors were gastric cancer, lung cancer, and leukemia. The relative incidence of gastric cancer was decreasing, while that of lung cancer was increasing. In the distribution of the histological types of lung cancer, adenocarcinomas were the most frequent types in both sexes. As has been noted in mortality statistics, we noticed a gradual shift in the peak age of lung cancer autopsy cases towards older patients. During the period under study, the peak shifted from patients in their sixties to patient in their seventies; this was true for most of the major histological types in both sexes. The male/female ratio of all lung cancer cases was 2.9, which was much lower than the ratio found in the United States and Europe, and very similar to the ratio of the mortality rates in Japan and other Asian countries. It was pointed out that the male/female ratios by age-group in each country is a very good reflection of the histological distribution. 相似文献
59.
Autopsy cases of lung cancer, 41,988 in males and 13,818 in females, consecutively registered between 1958 and 1987, were analysed statistically and compared with other case materials and mortality statistics. Cases of malignant tumor showed a gradual increase, and now comprise 60% of the total male and 55% of the total female autopsy cases. The percentage of lung cancer cases among the total autopsy cases was 9% for males and 5% for females. The percentage of lung cancer cases among total cases of malignant tumor was about 17% for males and 9% for females. Among fatal malignant tumors, gastric cancer and lung cancer showed the highest frequency. The relative incidence of gastric cancer was seen to decrease, whereas that of lung cancer increased. Of the histological types of lung cancer in both sexes, adenocarcinoma was the most frequent, followed by squamous cell carcinoma. During the period studied the peak age of patients with lung cancer shifted from the seventh to eighth decade, and a significant elevation of mean age was demonstrated for all of the major histological types in both sexes. The male:female ratio for all lung cancer cases was 3.0, which was much lower than those for the United States and Europe, but very similar to the ratios of mortality statistics in Japan and other Asian countries. As a result of a previous autopsy study at the University of Tokyo, it was also confirmed that the male:female ratio relative to age in each country reflects very well the histological distribution. 相似文献
60.
Nishioji K Okanoue T Itoh Y Narumi S Sakamoto M Nakamura H Morita A Kashima K 《Clinical and experimental immunology》2001,123(2):271-279
To clarify the role of IP-10 in autoimmune liver diseases, we studied the serum levels of IP-10 in 14 patients with autoimmune hepatitis (AIH), 23 patients with primary biliary cirrhosis (PBC), and 65 patients with chronic viral hepatitis (20 type B and 45 type C). The hepatic expression of IP-10 mRNA and the correlation between the serum levels of IP-10 and clinical parameters were also evaluated. In addition to 20 healthy controls, 16 rheumatoid arthritis (RA) patients were included as an extrahepatic inflammatory disease. The serum level of IP-10 was significantly (P < 0.02) higher in patients with AIH, PBC, and chronic hepatitis B and C than in healthy controls, and it was significantly correlated (P < 0.05) with the serum levels of aspartate aminotransferase and alanine aminotransferase in patients with AIH, PBC, and chronic hepatitis B and C. The serum level of IP-10 was not elevated in RA patients. After successful treatment of AIH and chronic hepatitis C, the serum level of IP-10 decreased to the same level as in healthy volunteers. As we previously showed in cases with chronic hepatitis B or C, in situ hybridization in both AIH and PBC cases demonstrated the expression of IP-10 mRNA in hepatocytes around focal or lobular necrosis surrounded by infiltrating mononuclear cells, whereas IP-10 mRNA was not expressed in areas around the damaged bile ducts in PBC cases. The present results suggest that IP-10 is specifically produced by hepatocytes in inflammatory areas irrespective of the aetiology of hepatitis, and that IP-10 may help to recruit T cells to the hepatic lesions in autoimmune liver diseases as well as in chronic viral hepatitis. 相似文献