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1.
To assess the infectivity of hepatitis B surface antigen (HBsAg)-containing body fluids other than blood, chimpanzees were inoculated intravenously with saliva and semen obtained from HBsAg-positive individuals implicated in non-percutaneous transmission of hepatitis B. Saliva and semen samples were negative for occult blood. The titer of HBsAg in saliva was on the average only 1/3,000 that of the corresponding serum. One chimpanzee, inoculated sequentially with saliva from three individuals, developed HBsAg at 9 weeks and serum glutamic pyruvic transaminase elevation at 13 weeks after injection. HBsAg persisted for 15 weeks. This animal also developed e antigen, anti-core antibody, and anti-surface antibody. Liver biopsies showed acute hepatitis that subsequently resolved. A second chimpanzee, inoculated with HBsAg-positive semen, developed HBsAg and elevated serum glutamic pyruvic transaminase 4 weeks after inoculation and then died suddenly without explanation. HBsAg was positive in two consecutive samples and was confirmed by specific neutralization. Autopsy did not reveal evidence of hepatitis. This study demonstrates that HBsAg-positive saliva and, probably, semen contain infectious virus and suggests that saliva and/or semen may serve as important mechanisms in the transmission of type B hepatitis.  相似文献   

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Oral glucose tolerance tests were performed on 16 addicts and 16 control subjects. A flat delayed glucose response was demonstrated, with hyperinsulinaemia, elevated plasma growth hormone and normal plasma cortisol in heroin addicts compared with control subjects. These studies suggest a relative insulin resistance in addicts which might be mediated by the elevated growth hormone or some other pharmacologic effect of the chronic opiate abuse.  相似文献   

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24 consecutive AIDS patients with wasting, and who had never received anabolic therapies, were evaluated to determine their profile of sex hormones and whether transformation of testosterone (T) to the nuclear androgen, dihydrotestosterone (DHT), was impaired. Eleven (46%) patients had normal testosterone and DHT (group I), 10 (42%) had normal testosterone but low DHT (group II), and 3 (12%) had low testosterone and low DHT (group III). Age, prior opportunistic complications, symptoms, serum albumin, hemoglobin levels, and CD4 lymphocyte counts were similar in the groups. DHT was significantly lower (22.2 +/- 6.8 microg/dl) in group II compared with group I (50.8 +/- 15.3 microg/dl). The ratio of T/DHT, a measure of the conversion of testosterone to DHT, in group I was 15.1 +/- 3.5, which was within the range for eugonadal young men. In group II, the ratio was 22.3 +/- 1.5, indicating a defect in generation of DHT. Patients in group II had lost 9.2 +/- 3.5 kg compared with 5.6 +/- 2.6 kg in group I (p = .015). Thus, a syndrome of low DHT with normal testosterone was associated with significantly greater weight loss than in patients with normal testosterone and DHT. Further studies are needed to clarify whether low DHT is a result of AIDS wasting or is causally related to weight loss and whether androgen therapy in the form of DHT could reverse some of the metabolic changes associated with AIDS wasting.  相似文献   

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Anti-HBs was undetectable in the plasma of 303 HBsAg-positive blood donors. The apparent reactivity of anti-HBs in the chromatographically isolated IgG fractions of these antigen-positive donors was shown to be nonneutralizable by HBsAg. The false-positive antiHBs reactions were apparently due to the isolation and concentration of IgG from the plasma which was initially nonreactive for anti-HBs.  相似文献   

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A novel recombinant interferon-alpha B/D hybrid was applied to assess tolerability, antiviral effect, and biological activity in chronic hepatitis B. The study was designed as an open nonrandomized trial. Treatment comprised a two-week run-in phase with 16 MU three times a week followed by 14 weeks with 64 MU three times a week (or 48 MU if toxicity occurred with 64 MU). Total follow-up was 36 weeks. Nineteen patients were included; three discontinued treatment during the run-in with 16 MU. Fourteen of 16 patients had 14 weeks of treatment with > or = 32 MU three times a week. Fourteen dose reductions were necessary in nine patients. The adverse experience profile was similar to other interferon-alphas. HBV-DNA decreased using all doses studied. HBV-DNA became undetectable in five patients, two of whom had HBeAg seroconversion. No HBsAg seroconversion was observed. It is concluded that interferon-alpha B/D is well tolerated in high doses. The anti-viral effect starts at at least 16 MU three times a week.  相似文献   

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Purified 22-nm forms of hepatitis B surface antigen (Hbsag) representing the three major antigenic subtypes (adw, ayw, and adr) were analyzed for their constituent polypeptides by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. No consistent difference in either the number or relative distributions of the polypeptides was observed for the various subtypes. Seven polypeptides were designated as P-1 through P-7 in order of their decreasing mobilities. By comparison with protein standards, their molecular weights were estimated as 23, 29.5, 36, 41.5, 53.5, 72, and 97 thousand. The P-1 and P-2 components represented the major polypeptides; P-2 and P-5 might by glycoproteins, based on their reaction with periodic acid-Shiff reagent. Each polypeptide contains cysteine residues. HBSAg was radiolabeled with 3H or 14C by reductive methylation or iodinated with 125I by the chloramine-T or lactoperoxidase procedures. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of labeled HBSAg yielded patterns identical to those obtained with protein stain. Comparison of HBSAg labeled by the chloramine-T and lactoperoxide procedures indicated that there was no distinction between internal or external components within the 22-nm structure.  相似文献   

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The histologic manifestations in the livers of chimpanzees inoculated with hepatitis A and B virus were compared with each other and correlated with biochemical, serologic, and virologic observations. Both types of hepatitis reveal alterations similar to those seen in human hepatitis, but the lesions--particularly the hepatocellular necrosis--are far milder. Hepatitis Type A in chimpanzees is a disease of short incubation period and duration. The hepatocytic alterations are mainly restricted to the periportal areas, and the parenchymal changes are less severe than the portal inflammation. The lesions correlated well with biochemical changes, the presence of virus in the liver, and its shedding in the stool. In contrast, experimental Type B hepatitis has a long incubation period and longer duration, involves the entire lobular parenchyma, and is, if anything, more severe in the lobular centers while portal inflammation is less conspicuous. Biochemical alterations and presence of virus in the liver correlate with these lesions, and the antibody response is similar to that seen in man. The chimpanzee is a useful model for studying the pathogenesis of viral hepatitis; additional study of serial morphologic events may contribute to our understanding of the clinical differences between hepatitis Type A and Type B.  相似文献   

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Thirty-nine carriers of hepatitis B surface antigen (HBs Ag) were studied with respect to e antigen and Dane particle-associated DNA polymerase activity and their relation to chronic hepatitis. Most of these individuals were followed for four or five years. A strong correlation between e antigen and DNA polymerase activity was found. Of the 22 e antigen-positive patients, 21 showed polymerase activity; none of the 13 e antigen-negative patients (one of whom had antibody to e antigen) had such activity. Three of four patients who became e antigen-negative after being e antigen-positive showed loss of polymerase activity. An independent clinical evaluation showed a strong correlation between chronic hepatitis and positive reactions in the tests for e antigen and DNA polymerase. The results emphasize the possibility of differentiating between groups of chronic carriers of HBs Ag by testing for e antigen and Dane particle-associated DNA polymerase activity. The differentiation may have important clinical implications.  相似文献   

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In order to evaluate the interference of hepatitis delta virus (HDV) in hepatitis B viral particle (HBsAg, HBcAg) expression in the liver of chronic HDV patients, 39 and 81 liver biopsies of HBsAg carriers seropositive for anti-HDV and anti-HDV negative controls, respectively, were studied. HBcAg was positive in 16.7% of the HBeAg-positive patients with HDAg in the liver and in 91,4% of controls. In contrast, in HBeAg- and anti-HDV negative patients the intrahepatic expression of HBcAg was detected in 32.6%. In anti-HDV negative patients the HBcAg liver expression correlated significantly with the HBeAg in serum (p < 0.00001). The distribution of HBcAg was exclusively cytoplasmatic in 30% of HDV-infected patients but mixed nuclear and cytoplasmic in 38.3% of the controls. The nuclear expression of HBcAg was decreased in chronic HDV infection. HBsAg was positive in 70.3% of patients who were anti-HDV positive and in 82.3% of controls. The membranous expression of HBsAg was detected less frequently in HDV-infected patients (p < 0.05) than in controls, while associated with HBeAg in serum of HBV carriers without HDV superinfection (p < 0.00001). The prevalence and the HBsAg cytoplasmic expression was not different for the chronic HDV infection or controls. Our results show: 1) decreased intrahepatic expression of HBcAg and membranous HBsAg in HBV carriers superinfected with HDV, suggesting decreased HBV replication in the liver of these patients. 2) the changing of HBcAg and HBsAg expression in the liver of HDV-infected patients, suggest not so much a decrease but rather a modulation in HBV replication.  相似文献   

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BACKGROUND/AIM: During the course of persistent hepatitis B virus infection, viral replication markedly decreases after acute exacerbation of liver inflammation accompanied by emergence of antihepatitis B e antibody (anti-HBe) and/or anti-hepatitis B surface antibody (anti-HBs). In some cases, however, persistent viral replication continues even after such exacerbation with or without HBeAg/anti-HBe seroconversion. The aim of the present study was to investigate the extent of genetic variations of HBV in this phenomenon. METHODS: Full-length HBV genomes were amplified by polymerase chain reaction from sera of three patients before and after acute exacerbation and were directly sequenced. RESULTS: In the whole genomes of 3215 nucleotides, only six nucleotide mutations for six amino acid substitutions (2 in the surface gene, 2 in the X gene, 1 in the core gene and 1 in the polymerase gene) were observed in patient 1, 15 mutations for 14 amino acid substitutions (1 in the pre-core codon 28, 4 in the surface gene, 4 in the core gene and 5 in the polymerase gene) were observed in patient 2, and 5 mutations for 6 amino acid substitutions (2 in the surface gene, 2 in the X gene, pre-core stop codon mutation and 1 in the polymerase gene) were observed in patient 3. Substitution in the a determinant of the surface gene, which encodes target epitopes for neutralizing antibodies, as well as those in the pre-core/core gene, which encodes epitopes for cytotoxic T cells, were mainly found. CONCLUSION: HBV that remained after the emergence of anti-HBe and anti-HBs are considered to possess mutations in epitopes for both humoral and cellular immunity. These mutant HBV may be involved in the pathogenesis of persistent hepatic injury after acute exacerbation.  相似文献   

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Eighty-seven cases of chronic persistent hepatitis (CPH) and 29 cases of chronic active hepatitis (CAH) were treated with Astragali Composita (AC), the clinical markedly effective rates were 69.0% and 55.2%, the total effective rates were 90.8% and 89.7% respectively; the sero-negative conversion rates of HBeAg and HBV-DNA were 27.7% and 28.0% respectively, they were higher than that of control group (P < 0.05-0.01). Eight ducks infected hepatitis B virus were treated with AC, sero-negative conversion of DHBV-DNA was seen in 3 ducks, DHBV-DNA levels of duck sera were lower after treatment than that before treatment (P < 0.05); mild inflammatory changes in liver tissues were seen in 3 ducks, its pathologic changes were milder than that of control groups; DHBV-DNA in liver tissues of 2 ducks was negative in situhybridization. The results indicated that AC had obvious effects of protecting liver tissues and some effects of inhibiting sera HBV and HBV replication.  相似文献   

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The crystal structure of the mouse major histocompatibility complex (MHC) class I molecule H-2Dd with an immunodominant peptide, designated P18-I10 (RGPGRAFVTI), from human immunodeficiency virus envelope glycoprotein 120 was determined at 3.2 A resolution. A novel orientation of the alpha3 domain of Dd relative to the alpha1/alpha2 domains results in significantly fewer contacts between alpha3 and beta2-microglobulin compared with other MHC class I proteins. Four out of ten peptide residues (P2 Gly, P3 Pro, P5 Arg and P10 Ile) are nearly completely buried in the Dd binding groove. This is consistent with previous findings that Dd exploits a four-residue binding motif comprising a glycine at P2, a proline at P3, a positively charged residue at P5, and a C-terminal hydrophobic residue at P9 or P10. The side-chain of P5 Arg is directed toward the floor of the predominantly hydrophobic binding groove where it forms two salt bridges and one hydrogen bond with Dd residue Asp77. The selection of glycine at P2 appears to be due to a narrowing of the B pocket, relative to that of other class I molecules, caused by Arg66 whose side-chain folds down into the binding cleft. Residue P3 Pro of P18-I10 occupies part of pocket D, which in Dd is partially split by a prominent hydrophobic ridge in the floor of the binding groove formed by Trp97 and Trp114. Residues P6 through P9 form a solvent-exposed bulge, with P7 Phe protruding the most from the binding groove and thereby probably constituting a major site of interaction with T cell receptors. A comparison of H-2Dd/P18-I10 with other MHC class I/peptide complexes of known structure provides insights into the possible basis for the specificity of the natural killer cell receptor Ly-49A for several related class I molecules.  相似文献   

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A serial prospective study of cellular immunity to HBsAg and liver-specific membrane lipoprotein was undertaken in 21 adults with acute hepatitis type B. Cellular immunity to HBsAg as determined by leucocyte migration inhibition with partially purified HBsAg as antigen was detected in all the patients during the recovery phase of the illness and was already detectable at the time of admission in 13 (62%) of the cases. In five of the remaining eight the titre of HBsAg in the serum at this time was high and in the whole series there was an inverse correlation between the degree of migration inhibition on admission and the peak HBsAg titre suggesting that antigen or possibly antigen/antibody complexes might be interfering with the demonstration of cellular immunity in vitro. Using a combination of minimum migration index recorded during the recovery period peak HBsAg titre, it was possible to compute the peak aspartate aminotransferase level with reasonable accuracy, a finding consistent with the hypothesis that the severity of the illness is related to both the number of infected hepatocytes and the vigour of the immune response to HBsAg. Evidence of an immune response to the liver-specific hepatocyte membrane lipoprotein was present in 50% of the patients tested at the time of admission, but was transient, having disappeared in every case by four weeks. The minimum migration index recorded with HBsAg as antigen was significantly lower in those with detectable sensitisation to the lipoprotein and it is possible that this autoimmune reaction is also generated by the interaction of T cells with viral antigenic determinants on the liver cell surface.  相似文献   

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AIM: Because there are few adoptable children in France, parents, for the last 20 years, have turned to international adoption. Alerted by the generally poor health of these children, we paid particular attention to their health problems and especially to infection by hepatitis B virus (HBV). POPULATION AND METHODS: The 60 internationally-adopted children seen from June 1993 to June 1997 were included in this study. All had hemogram and serum iron dosage, and search for intestinal parasites and tuberculosis was performed in each child, as were HBs antigen and HBs antibody screening. When HBs antigen was positive, HBe antigen and antibodies, HBV DNA and hepatitis C and delta serology were also studied. RESULTS: Six out of the 60 children were HBV chronic carriers. The six presented HBs antigen and five out of the six presented viral DNA. One child was co-infected with delta virus. Serum aminotransferase was normal in three children and increased in the three others. DISCUSSION: Some internationally adopted children are exposed to chronic infection by HBV. This concerns children coming from countries known for the high frequency of the disease, but also children with long stay in Eastern European nurseries. Chronic HBV carriage puts the child, as well as the family and other children in institutions and/or schools at risk, thus necessitating preventive measures.  相似文献   

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