Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0019163 (hepatitis B)
 38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The minor glycoproteins from hepatitis B surface antigen, GP33 and GP36, contain at their carboxy-terminal part the sequence of the major protein P24. They have 55 additional amino acids at the amino-terminal part which are coded by the pre-S region of the viral DNA.
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PMID:Structural relationships between minor and major proteins of hepatitis B surface antigen. 684 80

To investigate the association of human immunodeficiency virus (HIV) with various DNA viruses, including hepatitis B virus (HBV), cytomegalovirus (CMV) and Epstein-Barr virus, (EBV), simultaneous detection of HIV p24 antigen, HBV surface antigen and DNA, CMV-DNA and EBV-DNA expression was performed in phytohemagglutinin-stimulated peripheral blood mononuclear (PBMC) culture supernatants obtained from 54 individuals at risk for HIV infection. HIV expression in PBMC culture supernatants never occurred alone; expression of other viruses was always detected in the 24 samples expressing HIV antigen in vitro. Furthermore, in 16 patients expression of other viruses was detected without HIV expression, and in 14 patients none of the tested viruses were detected. These results indicate a strong association between the presence of HIV antibody and expression of DNA viruses in vitro (p = 0.0001). The coexpression of these viruses could be related to the evolution of HIV infection and AIDS.
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PMID:Association between HIV and other DNA viruses in vitro. 758 43

A major epidemic of human immunodeficiency virus type 1 (HIV-1) infections has developed in Thailand since 1988. The blood banks in Chiang Mai began screening donors for HIV-1 antibodies in February 1988 and for p24 antigen in April 1992. The trends of HIV-1 antibody prevalence were analyzed by type of donor (i.e., paid, replacement, and voluntary) for the period of 1988 through 1993. In addition, the prevalence of HIV-1 p24 antigen and of antibodies to syphilis, hepatitis B surface antigen, and hepatitis C virus was evaluated among blood donors at Chiang Mai University Hospital and the Thai Red Cross blood banks in Chiang Mai. The prevalence of HIV-1 antibodies in donor sera increased from 0.84% in 1988 to 3.23% in 1989. It continued to increase in subsequent years, reaching a maximum of 4.04% in 1991; the prevalence declined slightly in 1992 and 1993. In the first year of screening, the prevalence of HIV antibodies was highest in paid professional donors. The use of paid donors was discontinued on July 1, 1992, largely because of their high rates of HIV seropositivity. This action lowered the prevalence of HIV infection in the overall donor population in 1992 to 3.61%, from the peak of 4.04% in 1991. Antibody prevalence in replacement donors increased from 0.56% in 1988 to 5.82% in 1991. Screening for p24 antigen, introduced on April 29, 1992, identified 48 infected donors (among the 44,446 donors tested in 1992 and 1993) who were HIV p24 antigen positive. Altogether, 7 (0.016%) donors tested repeatedly reactive for p24 antigen, had positive p24 antigen neutralization tests, and were negative for antibodies to HIV. The exclusion of paid donors and the use of p24 antigen testing are justified in northern Thailand. Additional strategies to exclude donors at very high risk and to attract those at low risk for infection should be developed.
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PMID:Infectious disease markers in blood donors in northern Thailand. 787 21

Three different groups of asymptomatic children, aged from 12 to 24 months (30 subjects per each group), i.e. controls, only HIV, or HIV/hepatitis B virus (HBV) double infected, were studied, as concerned the following systemic immune parameters: immunoglobulin (IgG, IgM, IgA, IgD) levels; absolute numbers of blood CD+4, CD+8, CD+16 and CD+19 cells; phytohaemagglutinin (PHA)-blast responsiveness of T lymphocytes; natural killer (NK) cell activity--as tested by means of cytotoxicity assays; per cent suppression of PHA-dependent T cell blastogenesis in the presence of concanavalin A (Con A) selected T suppressor (Ts) cells. On the other hand, in 15 ARC-shifting cases belonging to HIV, and HIV/HBV groups, respectively, a second serum sample was collected and searched comparatively with the corresponding first serum sample, as regarded: presence of total and anti-p24 HIV antibodies, patterns of Western Blot (WB), as well as amounts of free p24-HIV antigen. In asymptomatic double HIV/HBV infected subjects, some immune disorders occurred, at a more significant degree, as compared to only HIV-infected. Once the shift toward ARC being installed, in both infected groups a decrease of anti-p24 HIV antibody presence, disappearance of corresponding band in WB confirmation test, as well as presence of free p24 antigen in serum, were noticed. However, greater amounts of p24 antigen in HIV/HBV infected, as compared to only HIV infected patients, were found. Some considerations about diagnostic and predictive value of presented data are discussed.
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PMID:Comparative study on some systemic humoral and cellular immune markers in only HIV or HIV and hepatitis B infected children. 804 85

Results are reported for a small study of 11 patients positive for HIV and with chronic active viral hepatitis. Low dose zidovudine/interferon alfa-2b combined treatment produced a general reduction in alanine aminotransferase activities and increased the CD4 lymphocyte count, hepatitis B e seroconversion, and the loss of HIV p24 antigen. The treatment was well tolerated and progression of HIV disease was not seen.
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PMID:Zidovudine plus interferon alfa-2b treatment in patients with HIV and chronic active viral hepatitis. 831 72

The usefulness of the direct virus detection by polymerase chain reaction (PCR) and reverse transcription/polymerase chain reaction (RT PCR) for blood donor screening was investigated, including the following viruses: cytomegalovirus (CMV), hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency type 1 virus (HIV1). Hepatitis C viraemia was detected by RT PCR in 97% of anti-HCV-positive haemophiliacs, in 48% of anti-HCV-positive hepatitis patients, in only 21% of anti-HCV-positive blood donors from North-West Germany, and not at all in 945 blood donors with elevated serum ALT. In order to compare HIV1 detection by PCR and by p24 antigen determination, we tested 34 anti-HIV1-positive AIDS patients for p24 antigen, HIV1 RNA and HIV1 provirus DNA. 97% had HIV1 provirus DNA, 35% had HIV RNA, but only 30% had p24 antigen. A multiplex PCR specific for HBV, HCV and HIV1 (RNA and DNA) was developed for the investigation of a blood donor population from Namibia, where HBV and HIV1 infections occur more frequently than in German blood donors. The prevalence of anti-HIV1 antibodies in this population was 0.6%. HIV1 RNA was never detected in the plasma of 2,569 anti-HIV1-negative donors. HIV1 provirus DNA was present in 75% of the 16 anti-HIV1-positive individuals. None of these anti-HIV1-positive blood donors was also positive for p24 antigen. CMV infections and reactivations in 130 immunocompromised heart transplant patients and in 420 healthy anti-CMV-positive blood donors were monitored using cytochemical detection of CMV early antigen, and PCR. CMV DNA was neither detected in the plasma nor in the leucocytes of any anti-CMV-positive blood donor. During the course of CMV reactivation in immunocompromised heart transplant patients, CMV DNA was always detectable first in granulocytes and afterwards in the plasma. The cytochemical demonstration of CMV early antigen was typically delayed by several days and was observed in only 11% of those blood samples which contained CMV DNA in leucocytes. The determination of CMV DNA in leucocytes proved to be the most sensitive method to detect viraemia. Thus, CMV detection in leucocytes is the method of choice for the monitoring of transplant patients. This method is also promising for blood donor screening. The sensitive routine monitoring of blood donations for virus infections by multiplex PCR is practicable. However, nucleic acid must be extracted both from the plasma and from the cellular compartments of blood in order to detect HIV and CMV provirus DNA. Lysate from EDTA blood is a suitable material for this purpose. The determination of the surrogate marker serum ALT activity is of no use in hepatitis C screening, and determination of p24 antigen is not required in HIV1 screening.
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PMID:[Molecular biological screening of viruses important to transfusion medicine]. 948 64

Three different groups of asymptomatic children, aged from 12 to 24 months (30 subjects per each group), i.e. controls, only HIV, or HIV/hepatitis B virus (HBV) double infected, were studied, as concerned the following systemic immune parameters: immunoglobulin (IgG, IgM, IgA, IgD) levels; absolute numbers of blood CD+4, CD+8, CD+16 and CD+19 cells; phytohaemagglutinin (PHA)-blast responsiveness of T lymphocytes; natural killer (NK) cell activity--as tested by means of cytotoxicity assays; per cent suppression of PHA-dependent T cell blastogenesis in the presence of concanavalin A (Con A) selected T suppressor (Ts) cells. On the other hand, in 15 ARC-shifting cases belonging to HIV, and HIV/HBV groups, respectively, a second serum sample was collected and searched comparatively with the corresponding first serum sample, as regarded: presence of total and anti-p24 HIV antibodies, patterns of Western Blot (WB), as well as amounts of free p24-HIV antigen. In asymptomatic double HIV/HBV infected subjects, some immune disorders occurred, at a more significant degree, as compared to only HIV-infected. Once the shift toward ARC being installed, in both infected groups a decrease of anti-p24 HIV antibody presence, disappearance of corresponding band in WB confirmation test, as well as presence of free p24 antigen in serum, were noticed. However, greater amounts of p24 antigen in HIV/HBV infected, as compared to only HIV infected patients, were found. Some considerations about diagnostic and predictive value of presented data are discussed.
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PMID:Comparative study on some systemic humoral and cellular immune markers in only HIV or HIV and hepatitis B infected children. 970 55

This longitudinal study examines differences in hepatitis B immune titres in children and adolescents with haemophilia to determine if they are dependent on how immunity was acquired (vaccination or natural infection), and whether they are related to the child's HIV status and/or are influenced by HIV disease progression. Serologic titres (HBcAb, HBsAb) and HBsAg were measured prospectively at baseline, and at years 1, 2 and 3 of follow-up in 126 HIV- and 207 HIV+ children and adolescents with haemophilia. Analyses were performed to assess the impact of HIV status on the measured titres, and for HIV+ subjects to examine the association with CD4+ lymphocyte counts and p24 antigen status. The results show that HIV+ children were more likely than HIV- children to lose vaccine-induced immunity as indicated by the loss of HBsAb. There was an increased risk of losing HBsAb with higher CD4+ counts and younger age. Re-immunization was not successful in seven of eight HIV+ children. Two subjects (one HIV+, one HIV-) entered the study HBsAg- but became HBsAg+ over the course of follow-up. Seven HIV+ subjects lost natural immunity as indicated by the loss of HBcAb. The loss of either HBsAb or HBcAb in HIV--subjects was negligible to absent. In conclusion, because of the loss of immunity in HIV+ children the viral safety of factor replacement concentrates for these children is an important consideration. HIV- children rarely lose immunity, therefore frequent measures of HBsAb are not necessary.
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PMID:Changes in hepatitis B serologic titers in HIV+ and HIV- children with haemophilia. 1058 18

Various methods are described for the elimination of infectious viruses from activated prothrombin complex concentrates (aPCCs) and for the analysis of the final products (AUTOPLEX T and FEIBA VH). Viruses of concern in human plasma-derived products are enveloped (hepatitis B and C, cytomegalovirus, Epstein-Barr virus, and human immunodeficiency virus [HIV]) and nonenveloped (hepatitis A and parvovirus B19). Donated blood used for AUTOPLEX T is screened for antihepatitis C, HBsAg, anti-HIV types 1 and 2, and p24 antigen. Plasma pools utilized for raw materials are also tested by PCR for HIV and hepatitis C virus. Partial virus inactivation and partitioning are achieved by purification of the aPCC. Further reduction of virus infectivity is accomplished by lyophilization and dry-heat treatment. Each step undergoes virus elimination validation studies in which a relevant sample is 'spiked' with the appropriate virus or model virus. The total reduction in virus from raw material to final product can then be calculated. For AUTOPLEX T the cumulative log10 reduction factors for several viruses vary from 4.2 to 14.3. This ensures an exceptionally high margin of safety. Definitive evidence for product safety was obtained by clinical observation of treated patients. The viral inactivation process of AUTOPLEX T involves a four-tier viral safety program, including Cohn alcohol fractionation and dry-heat treatment, in place of the two-stage vapour-heating process for FEIBA.
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PMID:Efficacy of viral clearance methods used in the manufacture of activated prothrombin complex concentrates: focus on AUTOPLEX T. 1059 84

During the last 5 years, considerable scientific and financial efforts have been made in the development of quantitative nucleic acid detection technology. For detection of human immunodeficiency virus (HIV), quantitative culture is time consuming, cumbersome and requires appropriate laboratory safety equipment. Quantitative determination of p24 antigen by enzyme immunoassay is of limited value due to its relatively poor sensitivity. Therefore, quantitative determination of viral load using nucleic acid amplification techniques is the most accurate, prognostic marker for HIV type 1 infection, independently of the CD4+ cell count. Hepatitis B virus (HBV) is not cultivable in vitro. Serological assays allow an accurate diagnosis and follow-up of acute or chronic infection. Quantification of HBV DNA is used for the monitoring of antiviral therapy, determination of infectivity and for resolution of unclear serological profiles, e.g. isolated anti-HBc reactivity, as well as for patients in which HBV mutants are suspected. Hepatitis C virus (HCV) can only be detected by molecular based assays because no cell culture system, which permits a reliable isolation of clinical specimens, is currently available. Furthermore, early diagnosis and follow-up of infection cannot be achieved with antibody serology. The prognostic relevance of quantitative HCV RNA determination is of limited value for the long-term prognosis of chronic hepatitis C. However, viral load may predict the outcome of antiviral therapy. Genetic diversity is another challenge for HCV RNA quantification.
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PMID:The role of viral load determination for the management of human immunodeficiency virus, hepatitis B virus and hepatitis C virus infection. 1116 79


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