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P Coursaget

Publications and source records attributed to P Coursaget.

At least 37 records · Page 2Linked to original sources
PubMed1998

Outbreak of enterically-transmitted hepatitis due to hepatitis A and hepatitis E viruses.

BACKGROUND/AIMS: One hundred and eleven patients with acute hepatitis and 61 controls were investigated for hepatitis serological markers in order to determine the viral etiology of cases involved in a waterborne epidemic of hepatitis observed in 1993 in Djibouti, Republic of Djibouti (East Africa). These cases occurred both in indigenous Djiboutians, and in French soldiers and their families in Djibouti. A retrospective study of the viral etiology of acute hepatitis cases observed in French soldiers and relatives living in Djibouti during the 3-year period preceding the epidemic was also undertaken. METHODS: HAV, HBV and HCV infections were investigated using commercial ELISA tests. HEV infections were investigated by testing IgG and IgM-specific antibodies by means of three different ELISA tests using recombinant proteins or synthetic peptides. RESULTS: Hepatitis A was observed in 37 (33%) and hepatitis E in 43 (39%) of the 111 cases of acute hepatitis recorded during this epidemic. Hepatitis B represented only 6% of the indigenous cases and hepatitis C was not observed among the cases investigated. Anti-HEV IgG antibodies were also detected in 19% of the indigenous control group. CONCLUSION: These results suggest that both HAV and HEV were responsible for this waterborne epidemic of acute hepatitis. However, HAV and HEV infections were not equally distributed between French expatriates and Djibouti residents. Whereas HAV infections were mainly observed in French patients, HEV was almost exclusively found in indigenous patients. This study reports for the first time a waterborne outbreak of acute hepatitis simultaneously due to HAV and HEV.

Adolescent↗
PubMed1998

The L1 major capsid protein of human papillomavirus type 16 variants affects yield of virus-like particles produced in an insect cell expression system.

The L1 major capsid proteins of six human papillomavirus type 16 (HPV-16) strains were expressed in insect cells by using recombinant baculoviruses. Virus-like particles (VLPs) which appeared similar to empty virions were identified by electron microscopy for all HPV strains investigated. However, the yield of VLPs produced varied in a range from 1 to 79 depending on the HPV-16 strain. The L1 proteins of these strains differed by up to 15 amino acids from the L1 protein of the prototype HPV-16 strain. Mutations in the amino acid region from residues 83 to 97 seemed to affect the level of expression of the L1 protein. These results are important when considering the development of HPV vaccines and serological tests. They indicate that strains inducing high levels of VLP production must be selected for the development of vaccines. Moreover, the L1 proteins of all strains investigated were able to bind with DNA. We also investigated the seroreactivities of VLPs derived from three different HPV-16 strains from Algeria, Senegal, and the Philippines by testing sera from women from 11 countries in immunoglobulin G-specific enzyme-linked immunosorbent assays. We observed a strong correlation between the reactivities of the three different VLP variants, independent of the geographical origin of the sera investigated. These results indicate that the three strains investigated are serologically cross-reactive despite the fact that their L1 proteins differ in 14 amino acids and suggest that VLPs derived from only one HPV-16 strain could be sufficient for the development of an HPV-16 vaccine and anti-HPV-16 tests.

Amino Acid Sequence↗
PubMed1998

Role of hepatitis E virus in sporadic cases of acute and fulminant hepatitis in an endemic area (Chad).

Forty-one patients with acute or fulminant hepatitis and 86 control patients were entered into a study of sporadic, acute, and fulminant hepatitis in the N'Djamena area of Chad in 1993. Acute hepatitis B was diagnosed in nine (22%) patients and acute hepatitis E in 27 (66%) patients. No acute hepatitis A was observed and 10% of the patients had serologic markers of hepatitis C virus (HCV) infection. Dual acute hepatitis B and E were observed in four patients (10%) and acute HEV infection was associated with chronic hepatitis B surface antigen carriage in 16 (39%). Epidemiologic findings concerning HBV from Chad suggest that these patients had undiagnosed chronic liver disease due to HBV, with acute deterioration caused by superimposed HEV replication. Moreover, it is obvious that in developing countries only the most severe cases of hepatitis are seen in hospital settings and a large proportion of them are related to superinfection with HBV and HEV. Antibody to HEV was observed in 22% of the control patients. This observation and the fact that epidemic and sporadic cases of HEV are observed in Chad indicates that HEV is highly endemic in this country.

Acute Disease↗
PubMed1998

[Philippe Maupas : hepatitis B vaccine discoverer].

Philippe Maupas Day 8th February 1981, an official ceremony with all the Profession, the Tours Faculty of Pharmacy was called Philippe Maupas, Hepatitis B vaccine discoverer - Galien Prize 1981. This communication presents the man, the scientist and the teacher. Born on 30th June 1939 in Toulon (south of France), married and the father of two children, Ph. Maupas was a man of action and an humanist. Full of enthusiasm, always available, passionate about his work, he never hesitated to brave the odds if he felt it would be of use to the community. With a pluridisciplinary training - Veterinary Doctor (1965), Pharmacist (1970), Science Doctor (1970) and Physician Doctor (1976) - he was Professor of Microbiology and Dean of the Faculty of Pharmacy of Tours. His scientific career fully illustrates his thirst for knowledge and his unflagging struggle against infectious diseases. Ph. Maupas approached his research work in a relaxed, imaginative frame of mind. Always passionate about his work and fired by spirit of Louis Pasteur, he was moved by a preoccupation of efficacy and a will of prevention in Public Health. He carried out research into both animal and human infectious diseases as well as anthropozoonosis. Ph. Maupas's most remarkable discoveries concerned the hepatitis B virus: he produced the first vaccine against hepatitis B and applied it to the prevention in man of this disease (1976); he confirmed the aetiological link between the hepatitis B and primary liver cancer.

France↗
PubMed1997

Characterization of hepatitis E virus (HEV) from Algeria and Chad by partial genome sequence.

The purpose of this study was to analyze partial nucleotide sequences and derived peptide sequences of hepatitis E virus (HEV) from two outbreaks of hepatitis E in Africa (Chad 1983-1984; Algeria 1978-1980). A portion of ORF3 and the major portion of ORF2 were amplified by Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR). The PCR products were sequenced directly or after cloning into the pCRII vector. Sequences were then compared to the corresponding regions of reported full length HEV sequences. In the ORF2 and ORF3 regions, the homology between the Algerian and the Chad isolates at the nucleic acid level was 92 and 95%, respectively. At the peptide level the homology was 98% in both regions. In these regions, both strains are more related to Asian strains at the nucleic acid level (89 to 95%) and at the amino acid level (95 to 100%) than to the Mexico strain. At the peptide level the differences are less apparent. Both African isolates have amino acid changes in common with some reference strains although the Chad isolate has three unique changes. These African strains of HEV, based on the ORF2 and ORF3 phylogenetic trees, appear to be a distinct phylogenetic group, separate from the Mexican and Asian strains.

Algeria↗
PubMed1997

Cell mediated immunity induced in mice by HPV 16 L1 virus-like particles.

Recombinant human papillomavirus (HPV) type 16 L1 virus-like particles (VLPs) expressed in the baculovirus system were used to investigate the cellular immune response to human papillomavirus type 16. The cell-mediated immune response was evaluated through immunization of mice with HPV 16 L1 virus-like particles using a lymphoproliferation assay and cytokine production and cytometric analysis of lymphocyte subsets. A significant proliferative response was observed which was associated with secretion of both interferon-gamma and interleukin-2. FACS analysis of splenic lymphocytes revealed that CD8+ T-cells were increased in the immunized mice. These results demonstrate that HPV 16 L1 VLPs induce a T-cell response characterized by a Th1 profile and confirm that the HPV 16 VLP is a reasonable candidate for vaccine development.

Animals↗
PubMed1997

Detection of antibodies to hepatitis E virus in patients with autoimmune chronic active hepatitis and primary biliary cirrhosis.

BACKGROUND: Viral hepatitis E (HIV) frequently causes epidemic outbreaks in many developing countries. It is also present in developed countries as imported cases. The role of hepatitis A virus as trigger for autoimmune chronic hepatitis has been demonstrated, and it has been suggested that this may also apply to HEV. METHODS: The presence of anti-HEV antibodies in serum samples from patients with autoimmune chronic active hepatitis (n = 52) and with primary biliary cirrhosis (n = 25) was investigated using an Abbott assay and a peptide-based test. RESULTS: Anti-HEV antibodies were detected with the Abbott test in 13% (7 of 52) of the patients with autoimmune chronic active hepatitis, but not of these were positive in the synthetic peptide-based test. CONCLUSION: These findings indicate the HEV is not associated with primary biliary cirrhosis but may be implicated in some cases of autoimmune chronic active hepatitis.

Autoimmune Diseases↗
PubMed1997

African strains of hepatitis E virus that are distinct from Asian strains.

Partial genomic sequences of four hepatitis E virus (HEV) strains from Africa (Morocco and Tunisia) and one from Central Asia (Tashkent, Uzbekistan) were obtained. The reverse transcriptase-polymerase chain reaction was used to amplify 5' and hypervariable regions of open reading frame 1 (ORF1) and a region overlapping all 3 ORFs. Sequence analysis of these regions revealed the African strains to be quite distinct from all known Asian strains but more similar to them than to the Mexican strain. Sequence analysis of the Tashkent strain revealed almost complete identity with another central Asian strain from Osh, Kirgizia. These results thus further confirm the geographical origin of HEV strain divergence.

Animals↗
PubMed1996

Production of human papillomavirus type 45 virus-like particles in insect cells using a recombinant baculovirus.

The L1 major capsid protein of human papillomavirus type 45 was expressed in insect cells using recombinant baculovirus technology. Human papillomavirus type 45 L1 major capsid protein self-assembled into empty virus-like particles (VLPs). These 50-60 nm diameter particles were present in the nuclei of recombinant baculovirus-infected insect cells and had a density of 1.29 - 1.30 g/cm3 in cesium chloride. The expressed human papillomavirus type 45 L1 protein sequence is identical to the reference human papillomavirus type 45 strain except for one amino acid located at position 49 of the human papillomavirus type 45 L1 protein. It must be noted that the quantity of purified human papillomavirus type 45 virus-like particles is at a lower level than that previously observed with human papillomavirus type 16. Nevertheless, the ability to generate preparative amounts of human papillomavirus type 45 virus-like particles is of great importance for the production of an anti-human papillomavirus vaccine.

Animals↗
PubMed1996

Detection by PCR of human papillomavirus genotypes in cervical lesions of Senegalese women.

In order to analyse human papillomavirus (HPV) infection in the Senegalese population, HPV DNA was sought in 65 women with evidence of cervical cytological abnormality and in 72 pregnant women. Ninety-four percent of the patients were positive for HPV DNA as compared to 24% of pregnant women. HPV 16 was detected in cervical smears in 42% of cases, HPV 18 in 39%, HPV 6 in 26%, HPV 11 in 15%, HPV 45 in 10%, HPV 52 in 3%, and HPV 31, HPV 33 and HPV 68 in 1.5%. HPV 16 and HPV 18 were detected in 16% and 7% respectively of pregnant women. HPV DNA of unknown type was detected in 6% of cases, and multiple HPV infections were observed in 28% of cases. Low risk genital HPVs (6/11) were detected in smaller proportions (17%) among high grade squamous intraepithelial lesions (SILs) than the low grade SILs (43%). High risk HPVs (16/18) were detected in high proportions both in low and high grade SIL lesions, though the highest frequency (70%) was observed among patients with high grade lesions. In conclusion, the results confirm that HPV infections are frequent in Senegal and that HPV 18 and 45 are detected in a high proportion of patients in Africa.

Adolescent↗
PubMed1996

Short report: polymerase chain reaction detection of hepatitis E virus in north African fecal samples.

Epidemics of enterically-transmitted non-A, non-B hepatitis were described in 1983-1984 involving French soldiers in Chad and in 1979-1980 in residents of Algeria. Hepatitis E virus (HEV) was subsequently implicated by serology. In this study, the presence of HEV in patient stool specimens from both outbreaks and from sporadic cases in residents of Chad (1994) was documented. This virus was detected in fecal suspensions by antibody capture of the virus and reverse transcriptase-polymerase chain reaction amplification of the viral RNA in the 3' end of open reading frame 2. Two of five epidemic cases from Chad (1983-1984) were positive, as well as one of five sporadic cases from Chad (1994), and two of three epidemic cases from Algeria (1979-1980). Of these 13 patients, 12 had detectable anti-HEV IgG in their serum. These results confirmed that HEV was the cause of hepatitis in at least five of these 13 patients.

Africa, Northern↗
PubMed1995

Detection of antibodies to L1, L2, and E4 proteins of human papillomavirus types 6, 11, and 16 by ELISA using synthetic peptides.

Antibodies against eight synthetic peptides spanning different epitopes located on L1, L2, and E4 proteins of human papillomavirus (HPV) types 16, 6, and 11 were examined in sera from 73 women infected by HPV and from 139 healthy controls. Only three of these peptides were reactive. Two located on proteins L2 and E4 of HPV 16 seem type specific since antibodies to these peptides were detected, respectively, in 21% and 15% of the HPV 16 infected patients and in 2.5% and none of women infected by other HPVs. The third peptide located on the L1 protein of HPV 6 bears a common epitope since antibodies to this peptide were detected not only in 85% of women infected by HPV 6 or 11, but also in 82% of women infected by other HPVs, and in 74% and 71% of the control groups (10-12-year-old children and adults, respectively). In conclusion, none of the peptides investigated seems useful to develop ELISAs for serological diagnosis of HPV infection.

Adolescent↗
PubMed1995

Simultaneous injection of plasma-derived or recombinant hepatitis B vaccines with yellow fever and killed polio vaccines.

Previous studies have shown an absence of interaction between hepatitis B (HB) vaccine and other vaccines used in EPI programmes except for an apparent decrease of yellow fever antibody levels when hepatitis B and yellow fever vaccines are given simultaneously. We have therefore reinvestigated the interaction of these two vaccines and assessed the absence of interaction between inactivated polio vaccine and recombinant or plasma-derived HB vaccine. The immune responses to polio vaccine injected simultaneously with plasma-derived or recombinant HB vaccine were observed to be equivalent and similar to those observed in the literature. In this randomized study, the immune responses to yellow fever injected simultaneously with plasma-derived or recombinant HB vaccine were comparable to those observed after separate administration of each vaccine. Moreover, no increase in adverse reactions was noted.

Female↗
PubMed1995

Detection of antibodies against human papillomavirus (HPV) type 16 virions by enzyme-linked immunosorbent assay using recombinant HPV 16 L1 capsids produced by recombinant baculovirus.

The L1 major capsid protein of human papillomavirus type 16 (HPV-16) was expressed in Sf-21 insect cells with a recombinant baculovirus. Virus-like particles obtained were purified and used to develop an enzyme-linked immunosorbent assay for detection of anti-HPV-16 antibodies in sera from 76 women with evidence of genital HPV infection and 79 controls. HPV-16-infected individuals developed antibodies directed at HPV-16 virions since reactivity against recombinant HPV-16L1 capsids was observed in 50% of them compared with only 6% in the general adult population. However, some cross-reactivities with sera from women infected with others HPV types were observed.

Animals↗
PubMed1995

Etiology of acute sporadic hepatitis in adults in Senegal and Tunisia.

Markers for acute hepatitis A, B, C and E virus infections were examined in the sera of 72 patients suffering from acute hepatitis in Senegal and Tunisia. Hepatitis B was responsible for 36% and hepatitis C for 21% of the cases. Acute hepatitis A was not diagnosed. HEV infection was not observed in Senegal and represents only 4% of the acute hepatitis cases in Tunisia.

Acute Disease↗
PubMed1994

Self-assembly of human papillomavirus type 16 capsids by expression of the L1 protein in insect cells.

The L1 major protein of human papillomavirus type 16 was expressed in Sf-21 insect cells with a recombinant baculovirus vector. Virus-like particles similar in appearance to empty virions were identified by electron microscopy at densities of 1.29-1.30. Purified particles reacted with monoclonal anti-HPV-16-L1 antibody in Western blot and immuno dot blot suggesting that conformational epitopes are present in the recombinant particles. Immunodot blot assays using human sera correlated with the detection of HPV-16 DNA by the polymerase chain reaction. The results suggest that HPV-16-L1 virions produced by the baculovirus system might be useful for developing serologic tests to measure antibodies to conformational epitopes and may offer potential for vaccine development.

Animals↗
PubMed1994

Familial clustering of hepatitis B virus infections and prevention of perinatal transmission by immunization with a reduced number of doses in an area of intermediate endemicity (Tunisia).

Hepatitis B surface antigen (HBsAg) was detected in 3.3% of 7162 pregnant Tunisian women tested and HBeAg in 9.6% of the HBsAg-positive mothers. Family members of 46 of these HBsAg-positive mothers (33 husbands and 61 children aged 1-6 years) were investigated for the presence of HBV markers. HBsAg was detected in 21% of the children and 18% of the husbands. Fifty children born to HBsAg-positive mothers received hepatitis B vaccine at birth, at the age of 2-3 months and at the age of 9 months. After immunization, anti-HBs were detected in 92% of them with an anti-HBs geometric mean titre of 415 mIU ml-1. Compared with the HBsAg carrier state in older siblings, the protective efficacy was estimated to be 60%. It was 100% for infants born to HBeAg-negative mothers, but only 31% for those born to HBeAg-positive mothers. For a better efficacy, the schedule of the EPI needs to be modified to include an immunization session at 1 month of age.

Adult↗