Search PubMed⌕ Search

Biomedical subjects

A Goudeau

Publications and source records attributed to A Goudeau.

At least 73 records · Page 4Linked to original sources

Evaluation of four commercial methods for identification and biotyping of genital and neonatal strains of Haemophilus species.

Four commercial methods for identification of Haemophilus species were evaluated in comparison to conventional methods using 188 genital and neonatal Haemophilus strains. In the case of discrepancies between results obtained by the different methods, DNA-DNA hybridization was performed. The four commercial systems and conventional methods showed excellent correlation of results in 167 strains (88%). DNA-DNA hybridization was performed in 8 strains with discrepant identification results and 13 strains with discrepant biotyping results. In 15 cases discrepancies could be explained by the fact that the strains belonged to a newly recognised species of Haemophilus.

DNA, Bacterial↗

Infection due to hepatitis delta virus in Africa: report from Senegal and review.

A review of the literature shows strong variations in the prevalence of hepatitis delta virus (HDV) among Africans seropositive for hepatitis B surface antigen (HBsAg). In Senegal, West Africa, prevalence of antibodies to HDV among asymptomatic HBsAg carriers appears to be linked to regional and/or socioeconomic factors. Antibodies to HDV were found in 22 (47%) of 47 HBsAg-seropositive patients with liver disease who were hospitalized in the main hospital of Dakar and in 4% to 44% of asymptomatic HBsAg carriers. Eight (36%) of 22 patients with liver disease were seropositive for IgM antibodies to HDV, whereas none of 18 asymptomatic subjects were seropositive (P less than .01). According to studies conducted in Europe and the United States, the presence of this marker may constitute support for the argument that HDV plays a role in the development of HBsAg-associated liver diseases in Senegal and, presumably, within the African continent.

Adult↗

Acute measles encephalitis of the delayed type: neuroradiological and immunological findings.

A case of delayed acute measles encephalitis in an immunosuppressed child is reported. Detailed immunological studies have shown defective humoral immunity (defective IgA, IgG2 and IgG3) and decreased natural killer activity. Neuroradiological examination by magnetic resonance imaging revealed several high signal lesions on T2-weighted images in the gray matter without clinical or pathological correlation. The implications of these findings are discussed.

Antigens, Viral↗

[Seroepidemiology of hepatitis A in six departments in West-Central France in 1991].

Antibodies to hepatitis A virus were sought for among residents of 6 "départements" of West-Central France during a routine medical check up provided by the national health insurance system to all affiliated persons. Among them 5,641 subjects (aged 6 to 60) were randomly selected to a sample size of 256 +/- 15 male or female subjects for each five-year age group. Anti-HAV were detected in 51% of the screened population. The prevalence was less than 5% in the 6-15 age group and increased by successive steps to exceed 90% in the subjects over 50. The highest increase was observed between the 26-30 (39%) and the 31-35 (57%) age groups. This study confirms the influence of socio-economical factors on the anti-HAV prevalence rate. Factors such as profession or scholar education were previously known, but the housing conditions and especially the number of siblings were identified in our present report. In relation to this low prevalence of anti-HAV among young adults, one may fear an increase of overt hepatitis cases which are known to be more frequent in adults than in infants or children. Moreover any break in hygiene may expose the population to an epidemia. Only active immunization with a vaccine against hepatitis A could efficiently prevent these individual and community-related risks.

Adolescent↗

Thymic abnormalities in fetuses aborted from human immunodeficiency virus type 1 seropositive women.

Pathological abnormalities of the thymus were found in 3 of 37 fetuses aborted from human immunodeficiency virus (HIV)-infected mothers. These lesions were located predominantly in the thymic cortex, which contains mostly immature lymphocytes. Areas of focal lymphocyte depletion were infiltrated with CD4+ macrophages and were associated with abnormalities of the epithelial stromal network. No evidence of extensive HIV infection in any of the 37 thymuses was detected by either immunofluorescence or in situ hybridization techniques, although rare cells that expressed HIV antigens were found in 3 fetuses. Although less extensive, this thymic fetopathy was similar to that described in postnatal acquired immunodeficiency syndrome thymuses, strongly suggesting that the lesions were related to HIV infection. Thymic fetopathy might represent the initial injury to the lymphoid system in HIV-infected infants in whom early and severe immunosuppression develops.

Abortion, Induced↗

[Prevention of perinatal hepatitis B virus transmission. Epidemiology and cost/efficacy ratio in the Paris region].

The HBs antigen (AgHBs) was detected in 152 out of 6605 (2.3 percent) pregnant women who attended four representative maternity clinics in the Paris region. In 98 percent of the cases this finding reflected chronic hepatitis B virus infection. Among women born outside France (47 percent of the women tested, 79 percent of the AgHBs positive women), the relative risk was 6 for Asiatics, 5.5 for Africans and 4 for French women born in overseas departments or territories. Whatever the women's geographical origin, studies of their medical history revealed no significant difference between AgHBs positivity and AgHBs negativity. Overcrowding and multiparity correlated globally with the presence of AgHBs, but this correlation was absent in French women born in France. In non-African and non-Asiatic women detection guided by medical and socio-familial criteria would not be efficacious. The authors recommend systematic detection of AgHBs in pregnant women and estimate at about 180,000 french francs the cost of prevention for each case evolving toward the vital complications of chronic hepatitis B virus infection, an outcome which in the long term may affect 600 individuals born each year and who had contracted the infection during the perinatal period.

Adult↗

Immunogenicity and safety in newborns of a new recombinant hepatitis B vaccine containing the S and pre-S2 antigens.

A study to evaluate the safety and immunogenicity of a recombinant hepatitis B vaccine containing the S and pre-S2 antigens (GenHevac B Pasteur) was conducted in healthy newborn infants. All infants received 20 micrograms of vaccine within 24 h of birth and at 1 and 2 months with a booster injection at month 12. The vaccine was administered alone in 19 infants born to low risk mothers, i.e. surface antigen (HBsAg)-negative and antibody to the core antigen (Anti-HBc)-positive mothers. The vaccine was administered in combination with 100 IU hepatitis B immune globulin (HBIg) at birth and 1 month in 18 infants born to high risk mothers, i.e. HBsAg positive mothers. In the group not receiving HBIg, the anti-HBs seroconversion rate at the 10 mIU ml-1 threshold was 50% 1 month after the first injection. In both groups, the anti-HBs seroconversion rates were 100% 1 month after the third injection and greater than 85% 1 month after the second injection. After the booster injection greater than 90% of the infants had an anti-HBs titre greater than 1000 mIU ml-1 which will probably provide them with adequate protection for several years. The kinetics of the anti-pre-S2 response was similar to that of the anti-HBs response and 100% of infants in both groups had seroconverted 1 month after the second injection of the vaccine. The side effects were scarce, all mild and transient.(ABSTRACT TRUNCATED AT 250 WORDS)

Antigens, Differentiation↗

Frequent and early in utero HIV-1 infection.

We have investigated in utero human immunodeficiency virus type 1 (HIV-1) transmission by analyzing human fetal tissues for the presence of viral DNA by means of the polymerase chain reaction (PCR). Thirty three fetal samples: thymus, spleen, and peripheral mononuclear blood cells (PMBC) were obtained at abortion (16 to 24 weeks) from HIV-1-infected asymptomatic women. The results of HIV-1-DNA detection were considered only in 9 cases where contamination of fetal samples by infected mother cells could be definitely eliminated by using primers specific for a polymorphic cellular locus. PCR allowed the identification of HIV-1 DNA sequences in 6/8, 8/9, and 5/9 of specimens from thymus, spleen, and PMBC, respectively. Positive results were shown in fetuses as early as 16 weeks. Viral cultures as well as assays for serum p24 HIV-1 antigen were negative in 9.9 and 33/33 tested, respectively. Therefore, our results indicate early and frequent in utero HIV-1 infection. Different patterns of viral activation after birth might then lead to either rapid or delayed onset of acquired immunodeficiency syndrome.

Base Sequence↗

Site-directed serology using synthetic oligopeptides representing the C-terminus of the external glycoproteins of HIV-1, HIV-2, or SIVmac may distinguish subtypes among primate lentiviruses.

In this study the presence of a highly immunogenic domain located at the C-terminus of the external glycoproteins (EGP) of human and simian immunodeficiency viruses (HIV-1, HIV-2, and SIVMAC) is shown using synthetic oligopeptides as antigens in enzyme immunoassays. This epitope is probably located within the last 13 and 15 residues of the EGP of HIV-1 and HIV-2, respectively. The C terminal epitope of the EGP of SIVMAC may involve residues located more upstream. Among the HIV-2/SIV serotype, we observed that the reactivity to the C-terminal epitope of gp120 was dependent of both species and geographical origin of the samples tested. It seems that this gp 120 C-terminal epitope could distinguish subtypes among the HIV-2/SIV serotype. Further studies, using site-directed enzyme immunoassays with synthetic peptides representing the C-terminus of the EGP derived from a wide variety of HIV2/SIV strains must be performed to confirm this observation. These kinds of assays may constitute important tools for use in seroepidemiological studies and broaden our understanding of the distribution and phylogenetic relationship of primate lentiviruses.

Amino Acid Sequence↗

Immune response to a major epitope of p24 during infection with human immunodeficiency virus type 1 and implications for diagnosis and prognosis.

A sequential inhibition enzyme-linked immunoassay (SIEIA) using a peroxidase-conjugated monoclonal antibody reacting to the sequence AAEWDRVHP of p24HIV-1 (amino acids 209 to 217 of p55) was developed in order to detect and determine the titer of antibody to this epitope in various populations of human immunodeficiency virus type 1 (HIV-1)-positive patients. There was a good correlation between SIEIA and a commercially available competition assay that uses recombinant p24 protein and polyclonal antibody to HIV-1 antigen, demonstrating the importance of the described epitope. Analysis of sera from French patients showed a decline of antibody to the AAEWDRVHP sequence associated with the progression of AIDS. No decrease was observed with serum samples from African patients. An immune response to the epitope was detected by SIEIA early in the course of seroconversion. Although our SIEIA uses a single p24 epitope, these data are in accordance with previously published studies in which antibodies to the whole p24 were analyzed. Sera reacting to p24 only (indeterminate profiles by Western blot [immunoblot]) did not bind to AAEWDRVHP. This epitope, which is conserved between HIV-1 and HIV-2/simian immunodeficiency virus, appears to be a major antigenic domain of p24. The area containing the sequence AAEWDRVHP and the corresponding monoclonal antibody may serve as a convenient alternative to whole purified p24 and polyclonal antibody in diagnostic and prognostic assays.

Amino Acid Sequence↗

Fine serotyping of human immunodeficiency virus serotype 1 (HIV-1) and HIV-2 infections by using synthetic oligopeptides representing an immunodominant domain of HIV-1 and HIV-2/simian immunodeficiency virus.

In this study, enzyme immunoassays for detection of type-specific antibodies to human immunodeficiency viruses (HIV) were developed by using short peptides corresponding to sequences located within the immunodominant domain of the transmembrane glycoproteins of both HIV-1 and HIV-2-simian immunodeficiency virus (SIV). The assays were highly sensitive with currently available sera from various geographical areas. Furthermore, they appeared to be more specific in HIV serotyping than the Western blot (immunoblot) assay, since all of the sera were clearly discriminated as one or the other type. It was also shown that in contrast to HIV-1, the C-terminal cysteine residue (amino acid 620, SIV from captive macaques, Mm142 strain) of the HIV-2-SIV peptide is not necessary for recognition of the peptide by antibody to HIV-2.

Amino Acid Sequence↗

[The perinatal transmission of the hepatitis B virus in the Paris area].

HBsAg was detected in 152 pregnant women among 6,605 (2.3%) screened in the prenatal clinics of four hospitals representative of the Paris metropolitan area. In 98% of cases, HBsAg positivity indicated chronic HBV carrier status. Among patients born out of continental France (47% of screened women, 79% of positive women) relative risk of chronic infection was 6 in Asians, 5.5 in Africans, and 4 in French women born in non-continental France. No significant difference in medical history was seen between HBsAg-positive and HBsAg-negative patients, in any of the birthplace groups. In women born out of continental France, number of children and crowding in the home were correlated with HBsAg-positivity; these correlations were not found in French women born in continental France. In non-African, non-Asian women, screening on the basis of medical, social and familial criteria (simulated in this study) would not be effective. Routine screening for HBsAg in pregnancy is advocated. The cost of the prevention of each case of perinatally acquired chronic HBV infection by routine screening followed by prophylactic treatment of a risk neonates was estimated at 180,000 French Francs (35,000 dollars). This approach is the only means of preventing the long-term life-threatening complications of chronic HBV infection in the 600 neonates born each year in France to HBsAg-positive mothers.

Africa↗

[Immunogenicity and harmlessness in the newborn of a vaccine (GenHevac B) containing the antigens S and pre-S2].

A study to evaluate the safety and immunogenicity of a recombinant hepatitis B vaccine containing the S and pre-S2 antigens (GenHevac B Pasteur) was conducted in healthy newborn infants. All infants received 20 micrograms of vaccine within 24 hours after birth, at 1 and 2 months with a booster injection at month 12. The vaccine was administered alone in 19 infants born to low risk mothers, i.e. surface antigen (HBsAg)-negative and antibody to the core antigen (Anti-HBc)-positive mothers. The vaccine was administered in combination with 100 IU hepatitis B immune globulin (HBIg) at birth and one month in 18 infants born to high risk mothers, i.e. HBsAg positive mothers. In the group not receiving HBIg, the anti-HBs seroconversion rate at the 10 mlU/ml threshold was 50% one month after the first injection. In both groups, the anti-HBs seroconversion rates were 100% one month after the third injection and above 85% one month after the second injection. After booster injection, more than 90% of the infants had an anti-HBs titre above 1,000 mlU/ml that will probably provide them with adequate protection for several years. The kinetics of the anti-pre-S2 response was similar to those of the anti-HBs response and 100% infants in both groups had seroconverted one month after the second injection of the vaccine. The side effects were scarce, all mild and transient. Given the protective role of the anti-pre-S2 antibodies, the precocity of the response to pre-S2 antigen may therefore increase the effectiveness of hepatitis vaccination.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗

[Perinatal transmission of the hepatitis B virus in Paris region].

HBsAg was detected in 152 pregnant women among 6,605 (2.3%) screened in the prenatal clinics of four hospitals representative of the Paris metropolitan area. In 98% of cases, HBsAg positivity indicated chronic HBV carrier status. Among patients born out of continental France (47% of screened women, 79% of positive women) relative risk of chronic infection was 6 in Asians, 5.5 in Africans, and 4 in French women born in non-continental France. No significant difference in medical history was seen between HBsAg-positive and HBsAg-negative patients, in any of the birthplace groups. In women born out of continental France, number of children and crowding of the home were correlated with HBsAg-positivity; these correlations were not found in French women born in continental France. In non-African, non-Asian women, screening on the basis of medical, social and familial criteria (simulated in this study) would not be effective. Routine screening for HBsAg in pregnancy is advocated. The cost of the prevention of each case of perinatally acquired chronic HBV infection by routine screening followed by prophylactic treatment of at risk neonates was estimated at 180,000 French Francs (35,000 dollars). This approach is the only means of preventing the long-term life-threatening complications of chronic HBV infection in the 600 neonates born each year in France to HBsAg-positive mothers.

Female↗