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BACKGROUND AND AIM: Parvovirus B19 has been reported to be detected in the sera of patients with acute or chronic hepatitis. The prevalence and clinical significance of B19 DNA in serum samples from patients with chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection were investigated. METHODS: Serum samples from 54 patients with HBV infection, 51 with HCV infection and 53 normal controls were examined for anti-B19 antibodies and B19 DNA by enzyme-linked immunosorbent assay (ELISA), the nested polymerase chain reaction (PCR), Southern blotting and direct nucleotide sequencing, respectively. RESULTS: Anti-B19 IgM and IgG antibodies were detected in 19 (35.2%) and 46 (85.2%) of 54 serum samples from patients with HBV infection, and eight (15.7%) and 36 (70.6%) of 51 serum samples from patients with HCV infection. B19 DNA was detected in serum samples of 20 (37%) of 54 patients with HBV infection and 12 (23.5%) of 51 patients with HCV infection, but not in 53 serum samples from normal controls. The occurrence of liver dysfunction was not affected by B19 infection in patients with HBV and HCV infection (P > 0.05). All of the 20 serum samples with B19 DNA from patients with chronic HBV infection and all of the 12 serum samples with B19 DNA from patients with chronic HCV infection exhibited TW-3 subtype and TW-9 subtype, respectively. The variant subtypes of B19 were found to be distinctive in patients with HBV or HCV infection. CONCLUSIONS: These data revealed that human parvovirus B19 infection was frequently found in patients with chronic HBV or HCV infection. The variant genotypes were present in patients with different chronic hepatitis. The coinfection of B19 with HBV or HCV did not increase the frequency of liver dysfunction in patients with chronic hepatitis. Long-term longitudinal studies are required to determine the natural course of parvovirus B19 infection and whether its coinfection affects the natural history of chronic hepatitis B or hepatitis C.  相似文献   
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Huang CN  Hsu TC  Chou HH  Tsay GJ 《Lupus》2004,13(6):450-454
One hundred and forty patients with Graves' disease [32 new patients, 54 treated with propylthiouracil (PTU) for a mean of 27.2 months and 54 treated with methimazole (MMI) for a mean of 48.6 months] were tested for anti-thyroid microsomal antibody (AMA), anti-thyroglobulin antibody (ATA), thyroid binding inhibitory immunoglobulin (TBII), and the non organ specific autoantibodies [i.e., anti-nuclear antibody (ANA), anti-double stranded DNA antibody (anti-dsDNA Ab), anti-cardiolipin antibody (aCL Ab) and anti-beta2-glycoprotein I antibody (IgG beta2GPI)]. Treatment with MMI or PTU produced a significant difference in IgG aCL Ab production but not in ANA, dsDNA Ab, IgM aCL or IgG beta2GPI. For those treated with MMI but not those treated with PTU, ANA and anti-dsDNA Ab were positively correlated. IgG and IgM aCL Ab were positively correlated overall and for those on MMI but not PTU treatment. No significant difference was found for any of the four non organ specific antibodies in AMA positive or negative patients but there was a significant difference in IgG aCL positivity rates for ATA positive and negative patients. On the other hand, ANA negative patients were significantly more likely to have higher TBII values. These results suggest that the appearance of the non organ specific autoantibodies is probably largely a coincidental effect of polyclonal activation - except, perhaps, for IgG aCL, which may be related to treatment.  相似文献   
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OBJECTIVE: The clinical significance of the presence of B19 DNA in patients with SLE was studied. METHODS: Sera from 72 patients with systemic lupus erythematosus (SLE), 23 patients with rheumatoid arthritis (RA), 18 patients with Sj?gren's syndrome (SS), eight patients with Raynaud's phenomenon (RP), five patients with primary biliary cirrhosis (PBC), five patients with polymyositis (PM), four patients with erythema infectiosum (EI) and 22 normal controls were examined for parvovirus B19 (B19) infection by serological assays, nested PCR and Southern blotting. RESULTS: Parvovirus B19 DNA was detected in 17 of 72 patients with SLE and in three of four patients with EI, but not in patients with other systemic rheumatic diseases. Of the 17 patients with B19 DNA, only one had IgG anti-B19 antibody and two had IgM anti-B19 antibodies, whereas IgG and IgM anti-B19 antibodies were detected in 27 (49.1%) and 21 (38.2%) of 55 SLE patients without B19 DNA respectively. All sera from the patients with EI contained both IgG and IgM anti-B19 antibodies. B19 DNA was found more commonly in sera from SLE patients without anti-B19 antibodies than in those with anti-B19 antibodies (P<0.05). CONCLUSIONS: B19 infection in patients with SLE may be due to lack of anti-B19 antibodies because of either the immunocompromised nature of the host or the use of immunosuppressive drugs. There was a higher prevalence of hypocomplementaemia and RP in patients with parvovirus B19 viraemia than in those without parvovirus B19 viraemia.  相似文献   
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Human parvovirus B19 has been found in various tissues in addition to erythroid lineage cells, and non-structural protein (NS1) is reported to induce cytotoxicity and apoptosis in erythroid lineage cells, but the mechanism in non-permissive cells is still unclear. To address this issue, we have constructed the NS1 gene in a cytomegalovirus episomal vector, pEGFP-C1 and transfected it into monkey epithelial cells, COS-7. EGFP-NS1 expression in transfected cells was monitored and assessed by fluorescence microscopy, RT-PCR and Western blot. The flow cytometric analysis showed that the NS1-transfected cells were arrested at G1 phase by paclitaxel treatment and there was increased apoptosis. The expression of p53, an important molecule in apoptosis and cell cycle regulation, and its downstream cell cycle kinase inhibitors p16(INK4) and p21(WAF1/CIP1) were up-regulated in the NS1-transfected cells. Also, increased expression of the pro-apoptotic Bcl-2 members Bax, Bad and activation of caspase 3 and caspase 9, but not the activation of caspase 8 or Fas were detected in the NS1-transfected cells. p53-induced Bax expression and subsequent activation of caspase 9 is probably the apoptotic pathway in NS1-transfected cells since activation of the caspase 9 was suppressed by the p53 inhibitor and apoptosis was significantly inhibited by the caspase 9 inhibitor. Our results suggest that the cell death of the NS1-transfected cells is associated with mitochondria related apoptosis. These findings might provide alternative information for further study and characterization of B19 NS1 protein in B19 non-permissive cells.  相似文献   
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