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991.
Autoimmune hepatitis (AIH) and primary biliary cirrhosis (PBC) are representative autoimmune liver diseases in which hepatocytes and intrahepatic bile ducts, respectively, are selectively damaged by autoimmune mechanisms. Bile duct injury and loss is characteristic of PBC and chronic non-suppurative destructive cholangitis (CNSDC), in particular, is a histological hallmark of PBC. In this report, we present an unusual case of AIH accompanied by CNSDC-like bile duct injury in a 46-year-old woman. The patient's serum aminotransferase level was abnormally high. The serum levels of alkaline phosphatase, gamma-GTP and IgG were also elevated, but the IgM level was within normal limits. The titer of antismooth muscle antibody (SMA) was 1:80, while antinuclear autoantibody (ANA) and the M2 fraction of antimitochondrial antibody (AMA) were both negative. Liver biopsy disclosed CNSDC-like bile duct injuries and severe interface hepatitis and lobular hepatitis with perivenular zonal necrosis were observed. The aggregate score of the International Autoimmune Hepatitis Group corresponded to the category of probable AIH. Immunohistochemically, histocompatibility leukocyte antigen-DR, which is aberrantly expressed in the damaged bile ducts of PBC, was not found in the injured bile ducts of this case. Laboratory data were much improved by treatment with prednisone, but ursodeoxycholic acid was not effective. Although the possibility of an overlapping syndrome of AIH- and AMA-negative PBC could not be excluded, this case was diagnosed as AIH with CNSDC-like bile duct lesions.  相似文献   
992.
993.
Extensive immunohistochemical analyses of the hyperplastic human palatine tonsil disclosed variegated B cell phenotypes on the lymphoid cells among the crypt epithelium. The reticular epithelial network was evident by cytokeratin immunostaining. The reticular epithelium near the crypt Iumen was positive for Iysozyme. Secretory component was negative, while HLA-DR was frequently expressed. Intramucosal small Iymphocytes, densely distributed in the Iuminal side, consisted mainly of B cells expressing CD19, CD20, CD21, CD22, CD45R, CD74, DBB42, HLA-DR, HLA-DQ, bcl-2 protein and surface lgM. Some B cells revealed mantle zone phenotypes (surface IgD+, CD5+, CD24+, DBA44+, CD10--, DNA7--). Cells of germinocyte phenotype (CD10+, DNA7+) were sparsely seen. A good number of intramucosal lymphoid cells were further labeled for CD11b, a phenotype of so-called B-1 cells. Plasma cells were clustered within the basal half. IgG was their major immunoglobulin class, followed by IgA, IgM and lgD classes. A smaller number of T cells (CD2+, CD3+, CD5+, CD45RO+, TCR αβ+) were identified among the epithelium. CD4+ cells predominated over CD8+ cells. TCR γΔ + cells were rare. Macrophages (CD68+), dendritic histio-cytes (S-100 protein+, CD1+), and natural killer cells (CD16+ or CD57+) were also dispersed. Another unique feature of this lymphoepithelial complex was the existence of HLA-DR intramucosal microvasculature, where lymphocyte recirculation was suggested. Proliferating cell nuclear antigen was detected commonly in the epithelial cells but rarely in the lymphoid cells. Possible lymphoepithelial interactions and morphologic similarities to the thymic medulla are discussed.  相似文献   
994.
The antigenic specificity of measles virus IgM antibodies in sera from patients with chronic active hepatitis not caused by hepatitis B virus has been examined. An immunosorbent column containing antihuman IgM covalently bound to Sepharose was used to pick up IgM from the sera. Radiolabelled measles virus antigens were then allowed to react with the IgM antibodies. The immune complexes were eluted and analysed by sodium dodecyl sulfate [SDS]-polyacrylamide gel electrophoresis. Four sera from patients with hepatitis B surface antigen [HBsAg]-negative chronic active hepatitis with high measles virus haemagglutination inhibition [HI] and complement fixation [CF] antibody titres and positive enzyme-linked immunosorbent assay [ELISA] for measles-virus-specific IgM were examined. The results were compared with those obtained using sera from patients with an acute measles virus infection and from healthy controls. In both patient groups, IgM antibodies with specificity against the matrix protein represented the major portion of the measles virus IgM. IgM antibodies against the measles virus nucleoprotein and probably against host-cell-derived actin were also present. The patient sera contained only traces of IgM antibodies with specificity against the measles virus haemagglutinin or fusion protein. No specific IgM antibodies were found in sera from healthy controls.  相似文献   
995.
BACKGROUND: Germins and the related germin-like proteins (GLPs) are glycoproteins expressed in many plants in response to biotic and abiotic stress. To test the potential impact of germins and GLPs, recombinant germin from Triticum aestivum (tGermin) and GLPs from Arabidopsis thaliana (tGLP), both produced in transformed tobacco plants, were used. METHODS: Sera from 82 patients with type I allergy to birch, grass or mugwort pollen and/or wheat were tested in immunoblot for IgE binding to tGermin and tGLP, and the IgE reactivity after chemical and enzymatic deglycosylation was analysed. The biological activity of tGermin and tGLP was determined in a histamine release assay and in skin prick testing (SPT). RESULTS: In an immunoblotting assay, 24 out of 82 tested sera (29.26%) from allergic patients showed IgE-binding to tGermin, and 18 of these sera (21.95%) displayed also IgE-binding to tGLP. The deglycosylation experiments indicated that glycan moieties contribute significantly to the IgE-binding of tGermin and tGLP. Both tGermins and tGLP induced specifically histamine release in an in vitro assay as well as in SPT. CONCLUSION: Our in vitro and in vivo findings demonstrate that germin and GLPs are capable to bind IgE most likely via carbohydrate determinants, and represent allergenic molecules.  相似文献   
996.
Growing evidence suggests that G‐proteins may be involved in pathogenesis and treatment of affective disorders. Several studies have reported altered levels and/or activities of stimulatory G‐proteins in depression. The aim of this study was to investigate whether a polymorphism in the stimulatory α subunit of G‐proteins (T/C point mutation in exon 5; ATT → ATC at codon 131) is associated with major depression or response to antidepressant treatment. Therefore, we performed a case‐control association study with 212 depressive patients and 137 healthy, unrelated controls. There was no evidence for an association between the investigated polymorphism in the Gαs gene and major depression, as well as to treatment response. The results of our study are in concordance with recently published findings which do not support the hypothesis that the gene for the stimulatory α subunit of G‐proteins is a major susceptibility factor in the pathophysiology of major depression. © 2002 Wiley‐Liss, Inc.  相似文献   
997.
Cardiomyopathy is a heart muscle disease with impaired stretch response that can result in severe heart failure and sudden death. A small proportion of hepatitis C virus (HCV)-infected patients may be predisposed to develop dilated cardiomyopathy (DCM) and hypertrophic cardiomyopathy (HCM). The molecular mechanisms involved in the predisposition remain unknown due in part to the lack of information on their genetic background. Because the human leukocyte antigen (HLA) region has a pivotal role in controlling the susceptibility to HCV-induced liver disease, we hypothesized that particular HLA alleles and/or non-HLA gene alleles within the human major histocompatibility complex (MHC) genomic region might control the predisposition to HCV-associated DCM (HCV-DCM) and/or HCV-associated HCM (HCV-HCM). Here, we present mapping results of the MHC-related susceptibility gene locus for HCV-associated cardiomyopathy by analyzing microsatellite and single nucleotide polymorphism markers. To delineate the susceptibility locus, we genotyped 44 polymorphic markers scattered across the entire MHC region in a total of 59 patients (21 HCV-DCM and 38 HCV-HCM) and 120 controls. We mapped HCV-DCM susceptibility to a non-HLA gene locus spanning from NFKBIL1 to MICA gene loci within the MHC class III-class I boundary region. Our results showed that HCV-DCM was more strongly associated with alleles of the non-HLA genes rather than the HLA genes themselves. In addition, no significant association was found between the MHC markers and HCV-HCM. This marked difference in the MHC-related disease susceptibility for HCV- associated cardiomyopathy strongly suggests that the development of HCV- DCM and HCV-HCM is under the control of different pathogenic mechanisms.  相似文献   
998.
999.
Structural-mechanical strength and swelling of gels consisting of gelatin and potassium hyaluronate (PHY) or potassium protine-chondroitin-4-sulfate (PPCS) were shown to depend on the ratio between the components. With low concentrations of PHY and PPCS the minimum of structural-mechanical strength coincided with the maximum of swelling of the gels. In zones of neutralization of the positive electric charges of gelatin by macropolyanions, high structural-mechanical strength of the gels coincided with the minimum of swelling. In high concentrations of PHY, structural-mechanical strength and swelling of the gel became equal to the values characteristic of a gel consisting of gelatin only, but in high concentration of PPCS there was an additional parallel increase in this strength and in swelling of the gel.(Presented by Academician of the Academy of Medical Sciences of the USSR S. S. Debov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 10, pp. 1211–1213, October, 1976.  相似文献   
1000.
B19 virus can be transmitted by contaminated blood or blood products. Recent observations, in healthy volunteers, suggest that active B19 infection can follow the administration of plasma pools with a concentration > or =10(7) genome equivalents/ml (geq/ml) of B19 DNA. However, patients receiving batches with levels of virus DNA lower than 10(4) geq/ml do not show any evidence of transmission of the virus. The aim of the study was to show, by in vitro assays, a threshold of viral load in B19 contaminated plasma pools over which the infection can be transmitted. Twenty plasma pools, each containing 960 single donations, were tested to correlate the viral load and the level of antibodies anti-B19 with the in vitro infectivity and expression of B19 virus. All the plasma pools, titrated for B19 viral load by competitive PCR, were inoculated into KU812Ep6 erythroid human cell line. Five of the nine contaminated plasma pools, with a B19 DNA concentration > or =3.60 x 10(6) geq/ml, were able to infect KU812Ep6 cells. In vitro infectivity was shown in KU812Ep6 cells at 24 h post-infection by in situ hybridisation and amplification assays for viral DNA and RNAs. Plasma pools with a viral load in the range of 6.00 x 10(3)-8.96 x 10(4) geq/ml did not show infectivity when inoculated into KU812Ep6 cells. Medium-high titres of IgG antibodies anti-B19 were detectable in all the plasma pools and the neutralising activity associated with specific IgG anti-B19 may explain the lack of infectivity of plasma pools contaminated with a low viral load. In conclusion, in situ hybridisation and amplification assays for viral DNA and RNAs in KU812Ep6 cells inoculated with plasma pools can be valid assays to test for the presence of infectious virus in the production of B19-safe material.  相似文献   
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