Biomedical subjects

F Barin

Publications and source records attributed to F Barin.

152 records · Page 9Linked to original sources

PubMedDate not supplied

Serological evidence for virus related to simian T-lymphotropic retrovirus III in residents of west Africa.

Serological evidence is presented here suggesting that a virus closely related to simian T-lymphotropic virus type III (STLV-III) infects man in Senegal, west Africa, a region where AIDS or AIDS-related diseases have not yet been observed. 25 sera from Senegalese individuals that were positive for antibodies to HTLV-III by enzyme-linked immunosorbent assay were examined for antibodies to HTLV-III and STLV-III by western blotting. Sera from individuals originating from regions where AIDS has been reported, such as the United States and Burundi (central Africa), reacted best with antigens of HTLV-III, although antibodies that cross-reacted with STLV-III p24 were also detected. Conversely, sera originating from Senegalese people reacted better with STLV-III than with HTLV-III. This was exemplified by the absence of reactivity in sera from both monkeys and Senegalese people to p41, an antigen regularly detected by sera from antibody positive individuals originating from central Africa or from the United States. In contrast sera from central Africa or the United States did not react with p32, the putative envelope transmembrane protein of STLV-III that is regularly detected by sera from both monkeys and antibody-positive Senegalese people. These results suggest that certain healthy Senegalese people have been exposed to a virus that is more closely related to STLV-III than to HTLV-III. The existence and study of such virus variants potentially with differential pathogenicity may provide important information for the development of an AIDS virus vaccine.

Africa, Western↗

PubMedDate not supplied

Aetiology of AIDS--antibodies to human T-cell leukaemia virus (type III) in haemophiliacs.

Human T-cell leukaemia virus type III (HTLV-III) is suspected of having a key role in the pathogenesis of acquired immune deficiency syndrome (AIDS). Epidemiological data suggest that AIDS is transmitted by an infectious agent through intimate contact with body secretions, blood or blood products. To maintain haemostasis, many haemophiliac patients depend on commercially prepared clotting concentrates made from large multi-donor plasma pools and are thus at increased risk of developing the disease. We report here that, using indirect membrane immunofluorescence and radioimmunoprecipitation with SDS-polyacrylamide gel electrophoresis, we have detected antibodies to HTLV-III in 30 of 47 (64%) asymptomatic haemophiliacs and in all of three haemophiliacs who either had or soon developed AIDS. Of 34 samples drawn before 1984, 18 (53%) were antibody-positive, whereas of 16 samples drawn during 1984, 15 (94%) were positive (P less than or equal to 0.002). These data suggest that exposure to HTLV-III antigens is widespread among asymptomatic haemophiliacs.

Acquired Immunodeficiency Syndrome↗

PubMedDate not supplied

AIDS vaccine predictions.

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Acquired Immunodeficiency Syndrome↗

PubMedDate not supplied

[Hepatitis B vaccine: characterization of the polypeptides of hepatitis B surface antigen (author's transl)].

In order to realize a new kind of hepatitis B vaccine, the polypeptide components of the outer-coat of the hepatitis B virus have been studied. The characterization of the polypeptides of purified hepatitis B surface antigen (HBsAg) was performed by SDS-polyacrylamide gel electrophoresis. Seven polypeptides were observed, designated P1 to P7, according to their increasing molecular weight: P1 (MW = 24,000), P2 (MW = 32,500) and P6 (MW = 78,000) represented the major components. When the reducing action was increased and followed by alkylation and citraconylation, a single polypeptide of low MW (5,000 less than MW less than 10,000) was isolated from HBsAg.

Electrophoresis, Polyacrylamide Gel↗

PubMedDate not supplied

[Epidemiology and pathologic results of chronic carriers state of hepatitis B in Mali].

The HB antigen of the hepatitis B (HB) virus, studied by counter immunoelectrophoresis shows a prevalence of 8.7% in 1,860 rural Malians and 11.3% in 764 blood donors from Bamako. Amongst 1,350 hospitalised patients, no correlation could be established between the HBs antigen chronic carriers state and other infectious diseases, malnutrition or genetic deficiencies. On the other hand, the prevalence of HBs antigen is particularly high in hepatic infections: acute and chronic hepatitis (53.5%), cirrhosis (31.5%) and hepatomas (25.3%). The study of the prevalence of hepatitis B by radioimmunoassay of the HBV seric markers was carried out in: --176 "healthy" town dwellers of which 97.2% were carriers of at least one marker--HBs Ag: 16.5%; anti-HBc alone: 34.1%; anti-HBs: 46.6%--. --30 subjects with cirrhosis--HBs Ag: 66.7%; anti-HBc alone: 10.0%; anti-HBs: 23.3%--. --42 subjects with PHC--HBs Ag: 47.6%; anti-HBc alone: 23.8%; anti-HBs: 28.6%--. The difference in HBs Ag carrier state between patients (cirrhosis and PHC) and controls, cross-matched for sex and age, is highly significative--p = 0,0001--.

Adolescent↗

PubMedDate not supplied

[Spontaneous reactivation of the hepatitis B virus?].

The authors present 4 cases of chronic AgHBs positive hepatitis, with reactivations of hepatitis B virus. The reactivations occurred spontaneously, as mentioned in references. The authors appreciate that the cause of B virus reactivation bases upon factors which modify the immune status of the host. Alcohol is one of these factors, not yet mentioned in references as cause of virus B reactivation. Are also presented data about the existence of virus B mutants, in the studied patients, which could play a role in the reactivation of chronic hepatitis B.

Adult↗

PubMedDate not supplied

[Hepatitis B virus reactivation in patients infected with HIV].

The authors study the reactivation of B hepatitis virus in three HIV infected patients, correlating the moment of reactivation of and the CD4 and CD8 lymphocytes. Prior to the B viral reactivation, the three patients were with Ac HBc IgG (+) in serum, assessing that the presence of AC HBc IgG is insufficient to prevent the reactivation and to consider a B hepatitis cured. In two patients, prior to the B virus reactivation, AgHBs was (-) in the serum. It is considered that the predominant hepatocytolysis mechanism is the viral one, in the stage of B virus reactivation in patients with AIDS, the cell immunity mechanism being depressed.

Biomarkers↗

PubMedDate not supplied

[Anti-HCV serology for screening, diagnosis and surveillance of hepatitis C: role of the immunoblot].

Screening for antibody to hepatitis C virus (anti-HCV) is usually carried out using microplate enzyme immunoassays (EIA). According to French Ministry of Health recommendations, any positive or dubious result has to be controlled on a second blood sample with a anti-HCV assay differing from the one used for the initial screening. This second test can either be another EIA or an immunoblot assay. The present article investigates the advantage of a strip immunoblot assay including 4-viral peptides (Riba-3) for this control. The use of Riba for the early diagnosis of hepatitis C infection and for the follow-up of infected patients is also evaluated. Riba can be used to assess false positive EIA reactions, for instance in cases with isolated antibody to NS5. From large clinical series, it appears that positive Riba serum profiles can be divided in two main groups: Strongly positive sera associate at least strong (3 or 4+) anti-capsid and anti-NS3 antibody reactivities. These profiles are often completed by anti-NS4 and/or anti-NS5 reactivities. Such profiles are associated with HCV viremia in about 90% of the cases. In this group, prevalence of viremia reaches 100% in patients with elevated level of serum alanin aminotransferase (ALT) and is slightly less frequent, 85%, in patients with normal level of ALT; Weakly positive sera lack either anti-capsid or anti-NS3 antibodies or exhibit only low reactivities (1+ or 2+) to these two antigens. These profiles can also be associated with antibodies to NS4 and/or NS5. Only 10% of patients with such Riba profiles are viremic. Weakly positive profile can be encountered during the early phase of HCV infection (recent seroconversion) or in patients who experience a favourable evolution of their HCV infection. Change of Riba profiles during follow-up provides fruitful information on recent seroconversions (increase in number and intensity of the reactivities). It can also help predict the outcome of HCV infection, a diminution of the intensity of Riba reactivities will confirm the extinction of viral replication.

Hepatitis C↗