PubMed Health⌕ Search

Biomedical subjects

J Ducos

Publications and source records attributed to J Ducos.

At least 19 recordsLinked to original sources
PubMed2001

Hepatitis C in a ward for cystic fibrosis and diabetic patients: possible transmission by spring-loaded finger-stick devices for self-monitoring of capillary blood glucose.

OBJECTIVE: To identify the routes of transmission in a nosocomial outbreak of hepatitis C virus (HCV) infection. DESIGN: Epidemiological investigation, including screening for HCV of hospitalized patients, and a retrospective cohort study, review of hygiene and medical practices, and molecular comparison of HCV isolates. SETTING: A specialized care unit for cystic fibrosis (CF) and diabetic patients at an acute-care facility in the south of France. RESULTS: Of the 57 CF patients (age in 1995: 2-28 years), 38 (66.7%) were tested and 22 (57.9%) were anti-HCV positive. Eight (50%) of 16 patients with anti-HCV antibody tested by polymerase chain reaction were viremic. No patients had received blood products or had any history of intravenous drug use. All 18 (100%) patients with CF who had ever undergone self-monitoring of capillary blood glucose in the unit were anti-HCV positive, compared to 4 (20%) of 20 who had not (relative risk, 5.0; 95% confidence interval, 2.1-12.0). Seventy (39.5%) of the patients with diabetes were screened for anti-HCV; 12 (18.8%) tested positive, with 3 (25%) positive for HCV-RNA. Patients with diabetes had routine capillary blood glucose monitoring while hospitalized and shared with CF patients the same spring-triggered devices for capillary blood glucose monitoring. The disposable platform of the devices was not changed between patient use. All HCV isolates belonged to the type 1, subtype b, and phylogenetic analysis showed a close homology by sequencing of NS5b and E2/HVR regions. CONCLUSION: As reported earlier for the hepatitis B virus, shared spring-triggered devices for capillary blood glucose monitoring by finger puncture may transmit HCV. Strict application of Standard Precautions procedures is warranted in any healthcare setting.

Adolescent↗
PubMed1999

Hepatitis C virus genotypes and quantification of serum hepatitis C RNA in liver transplant recipients. Relationship with histologic outcome of recurrent hepatitis C.

The reasons for wide variations in the severity of recurrent hepatitis C after liver transplantation are unclear. We studied liver transplant recipients to assess the effect of hepatitis C virus (HCV) genotype and HCV RNA quantification on histologic progression of recurrent hepatitis C after transplantation. Twenty-five patients underwent transplantation for HCV cirrhosis and were followed up with virologic and histologic assessments for a mean of 51 months. HCV genotype was determined by line probe assay. HCV RNA was quantitated in serum samples by nested polymerase chain reaction. The HCV genotype 1 was detected in 17 patients and other genotypes in 8. Acute lobular hepatitis developed in 17 patients 162 days posttransplantation on average. Long-term biopsy specimens (mean, 51 months after the date of liver transplantation; range, 24-86 months) showed chronic hepatitis in 19 patients (mild, 5; moderate, 9; and severe, 5, 2 with extensive scarring). The serum alanine aminotransferase level was correlated with hepatocyte necrosis (piecemeal and lobular) but not with portal inflammation or fibrosis. Patients infected with genotype 1 had a higher Knodell score, and the 5 patients with severe hepatitis C all were infected with genotype 1. HCV RNA levels were significantly higher in patients with genotype 1 than in patients with other genotypes, as were the severity of histologic recurrence and levels of viral replication.

Adult↗
PubMed1998

Prevalence of antiphospholipid antibodies in patients with chronic liver disease related to alcohol or hepatitis C virus: correlation with liver injury.

Antiphospholipid antibodies (APAs) have been reported in various clinical conditions. However, the pathogenesis and clinical significance of these antibodies are still unclear. The objective of this study was to assess the prevalence of APAs in patients with chronic alcohol- or hepatitis C virus (HCV)-related liver disease and to evaluate their relation to the underlying liver disease. We prospectively studied 201 patients referred to an hepato-gastroenterology department, including 77 patients with a history of alcohol abuse (group I) and 124 with chronic HCV infection (group II), and 107 healthy subjects (control population). Liver biopsy was performed in all patients. In cirrhotic patients, the severity of the liver disease was assessed with the use of Child's classification, as modified by Pugh. Several biologic parameters, including lupus anticoagulant and anticardiolipin antibodies, were determined. Forty-eight percent of patients in group I and 33% of those in group II had APAs. Among cirrhotic patients, APAs were more frequent in patients with Child grade B or C than in those with grade A severity. In patients with chronic HCV-related liver disease, a correlation was found between APA levels and liver fibrosis (P = 0.009); no relation was found between APA levels and histologic liver disease activity (P = 0.25). In the control group, one subject was APA-positive. None had lupus anticoagulant. APAs seem to be frequently associated with chronic liver disease of various causes. These results suggest further investigations on the potential role of these antibodies in fibrosis or liver injury.

Adult↗
PubMed1998

In vitro infection of adult normal human hepatocytes in primary culture by hepatitis C virus.

In vitro infection of adult normal human hepatocytes in primary culture has been performed for investigating the replication cycle of hepatitis C virus (HCV) in differentiated cells. Hepatocytes were prepared from liver tissue resected from donors who tested negative for HCV, and inoculation was performed 3 days after plating with 33 HCV serum samples of different virus load and genotype. The presence of intracellular HCV RNA, detected by a strand-specific rTth RT-PCR assay, was used as evidence of infection. A kinetics analysis of HCV replication revealed that intracellular negative-strand RNA appeared at day 1 post-infection with a maximum level at days 3 and 5, followed by a decrease until day 14. At day 5, we estimated that the copy level of viral RNA was amplified at least 15-fold in infected cells. The level of intracellular HCV RNA in response to different serum samples was reproducible from one hepatocyte culture to another, suggesting that there is no inter-individual variability in the susceptibility of hepatocytes to HCV infection. These findings indicate that adult human hepatocytes in primary culture retain their susceptibility to in vitro HCV infection and support HCV RNA replication. This model should represent a valuable tool for the study of initial steps of the HCV replication cycle and for the evaluation of antiviral molecules.

Adult↗
PubMed1997

Hepatitis C virus genotypes and quantitation of serum hepatitis C virus RNA in liver transplant recipients: relationship with severity of histological recurrence and implications in the pathogenesis of HCV infection.

The reasons for the wide variation of incidence and severity of recurrent hepatitis C after liver transplantation are not clear. We have studied liver transplant recipients to assess the impact of hepatitis C virus (HCV) genotype and HCV RNA quantification on HCV recurrence after transplantation. Twenty-two patients received transplants for HCV cirrhosis and were followed up with virological and histological assessments. Mean follow-up was 39 months. HCV genotype was determined with line probe assay (Inno-Lipa). HCV RNA quantity was determined in serum samples by use of polymerase chain reaction nested assay. HCV genotype 1 was detected in 13 patients and other genotypes in 9. Histological recurrence rates were 69% in patients with genotype 1 and 66% in patients with other genotypes. All cases of severe histological injury (chronic active hepatitis or cirrhosis) were observed in patients with genotype 1. HCV RNA quantity was significantly higher in patients with genotype 1 (mean, 2.023 x 10(3) copies/mL) than in patients with other genotypes (mean, 27,403 copies/mL). In conclusion, the severity of histological recurrence after liver transplantation for HCV disease was higher in patients infected by HCV genotype 1 than in those infected with other genotypes. The levels of viral replication were higher in patients with HCV genotype 1 than in those with other genotypes.

Adult↗
PubMed1996

Hepatitis B virus (HBV)-specific in vitro antibody production by peripheral blood mononuclear cells (PBMC) after vaccination by recombinant hepatitis B surface antigen (rHBsAg).

To study the immunization induced by rHBsAg, we analysed the in vitro antibody production (IVAP) to HBsAg by PBMC from 18 subjects vaccinated by two injections on days 0 and 30. HBsAg-specific IVAP was detectable in all subjects after both the first and the second injection, and lasted for about 10 days and then disappeared. However, when the spontaneous HBsAg-specific IVAP became negative, HBsAg stimulation of PBMC cultures induced again a specific HBsAg IVAP. Cultures of cell populations separated by erythrocyte rosetting or Percoll density centrifugation showed that the cells responsible for spontaneous secretion, after in vivo stimulation, were low-density B lymphocytes. High-density B lymphocytes were involved in anti-HBs production induced by in vitro stimulation when spontaneous secretion disappeared. These data suggest that the IVAP test could be a source of important information along with serologic analysis for exploration of the immune response to hepatitis B vaccine.

Adult↗
PubMed1994

Spontaneous in vitro anti-human immunodeficiency virus type 1 antibody secretion by peripheral blood mononuclear cells is related to disease progression in zidovudine-treated adults.

As part of a continuous search for surrogate markers of therapeutic efficacy in AIDS, spontaneous in vitro production by peripheral blood mononuclear cells of antibody to human immunodeficiency virus type 1 (HIV-1) was investigated in 50 HIV-1-infected adults. It was independent of CD4+ cell counts, p24 antigenemia, serum beta 2-microglobulin concentration, and clinical status of the patients. The effect of zidovudine on this antibody secretion and the appearance of signs or symptoms of HIV-1 disease progression were evaluated in 20 patients over 24 weeks. Anti-HIV-1 antibody secretion decreased significantly (P = .002) as of the first month of zidovudine treatment only in the 13 HIV-1-infected patients without disease progression. This is earlier than the occurrence of variations in CD4+ cell count and serum beta 2-microglobulin concentration. These results suggest that in vitro antibody production could be a surrogate marker for evaluation of the in vivo antiretroviral efficacy of zidovudine, even in p24 antigen-negative patients.

Adult↗
PubMed1994

Hepatitis C virus (HCV)-specific in vitro antibody secretion by peripheral blood lymphocytes: correlation with progression of disease and HCV RNA in HCV antibody-positive patients.

Hepatitis C virus-specific in vitro antibody production (HCV IVAP) by peripheral blood lymphocytes in 53 HCV antibody-positive patients was investigated in comparison with alanine aminotransferase (ALT) levels and HCV RNA in serum samples. All 29 HCV IVAP-positive patients were HCV RNA positive; 26 had elevated ALT levels. Among the 24 HCV IVAP-negative patients, 16 were HCV RNA negative, with 12 presenting normal ALT values. These data indicate that HCV IVAP results are highly correlated (P < 0.001) with HCV RNA results and ALT levels. Our study indicates that HCV IVAP can be used as a novel assay in the diagnosis and pathogenesis exploration of HCV infection.

Adult↗
PubMed1993

Comparative humoral responses to human immunodeficiency virus type 1-p24gag linear B-cell epitopes among individuals showing atypical western immunoblotting reactions and implications for diagnosis.

Serum specimens from 25 individuals with an isolated human immunodeficiency virus type 1 (HIV-1) core antigen reactivity in a Western immunoblot test were examined for their reactivities with HIV-1 virions, control cellular antigens, HIV-1-Bru p24gag recombinant protein (p24gag), and a panel of 22 p24gag-derived peptides. The results were as follows: (i) serum specimens from eight HIV-1-uninfected subjects did bind to virions but failed to bind to p24gag; (ii) sera from 13 HIV-1-uninfected subjects and from one HIV-2-infected patient reacted with HIV-1 virions and p24gag but failed to bind to any of the peptides expressing major p24gag epitopes, and (iii) 3 serum specimens obtained from one neonate carrying anti-HIV-1 maternal antibody and from two HIV-1-infected subjects who had seroconverted during the study reacted with HIV-1 virions, p24gag, and one or more peptides containing the major p24gag epitopes. Our data suggest that the combination of p24gag and appropriate peptides could be useful for resolution when atypical Western immunoblot results are encountered.

Amino Acid Sequence↗
PubMed1992

Survival of human monoclonal anti-Rho (D) antibodies in the rhesus monkey.

In vivo half-life of a 125I-labeled human anti-D monoclonal antibody (mAb) and that of 131I-labeled Rho-GAM was assessed in a rhesus monkey injected simultaneously with both reagents. The half-life of the mAb was 7.9 days, compared to 17 days of Rho-GAM. Survival of the second dose of mAb, given 34 days after the first injection, was identical to that of the first dose, thus showing that the human mAb did not elicit an immune response. The in vitro produced human mAbs appear to be an alternative, unlimited source of anti-D antibodies for possible use in prevention of feto-maternal Rh immunization.

Animals↗
PubMed1991

Spontaneous in vitro secretion of antibody to cytomegalovirus (CMV) by human peripheral blood mononuclear cells: a new approach to studying the CMV-immune system interaction.

The in vitro secretion of cytomegalovirus (CMV)-specific antibodies by peripheral blood mononuclear cells (PBMC) was analyzed in patients with acute CMV infection and CMV-seropositive patients infected with human immunodeficiency virus. This active and spontaneous in vitro secretion was not affected by the depletion of T cells or adherent cells. The number of anti-CMV antibody-secreting cells was estimated to be 28-176/10(6) PBMC; 30%-65% of the total in vitro antibody production was CMV-specific. This secretion seemed to be independent of in vitro polyclonal B cell activation, in vitro antigen-specific lymphocyte stimulation, or in vivo Epstein-Barr virus-induced B cell transformation. In vitro anti-CMV antibody production may therefore result from an in vivo stimulation of the immune system by CMV antigens and might indicate CMV replication in the host.

Acute Disease↗
PubMed1991

Analysis of the spontaneous in vitro anti-HIV-1 antibody secretion by peripheral blood mononuclear cells in HIV-1 infection.

We studied the spontaneous in vitro secretion of anti-HIV-1 antibodies by peripheral blood mononuclear cells (PBMC) from HIV-1-infected patients. Specific antibody production was detected in supernatants of PBMC cultures using an ELISA; HIV-1 specificity was confirmed by antigen adsorption and Western blotting. This antibody secretion was found to be an active phenomenon and was not due to a release of plasma antibodies passively adsorbed onto the cell membranes. In all positive supernatants, anti-HIV-1-secreted antibodies were directed against env-encoded antigens and many supernatants also contained antibodies to pol- and gag-encoded antigens. PBMC from all HIV-1-infected patients tested (140 adults and 18 infants) secreted anti-HIV-1 antibodies. This production was found during all the clinical stages of HIV-1 infection. Our results suggest that this spontaneous HIV-1-specific antibody secretion represents a marker of HIV-1 infection. Detection of these antibodies could be a valuable tool for early confirmation of HIV-1 infection in neonates born to HIV-1-seropositive mothers.

Adolescent↗
PubMed1991

Polyreactivity of human monoclonal antibodies: human anti-Rh monoclonal antibodies of IgM isotype are frequently polyreactive.

The specific aim of this study was to characterize human anti-Rh monoclonal antibodies cross-reacting with self-antigens. We studied supernatants from man-mouse hybridomas and from lymphoblastoid cell lines. Man-mouse hybridomas were established by fusion of peripheral blood lymphocytes from healthy individuals recently immunized against Rh alloantigens, with mouse myeloma (or man-mouse heteromyeloma) cell lines. Lymphoblastoid cell lines were produced by Epstein-Barr virus induction of lymphocytes from identical sources. Of the 55 monoclonal alloantibodies studied, 11 also reacted with intracellular self-antigens as demonstrated by immunofluorescence assay on cryostat sections of human tissues. This cross-reactivity was mainly a property of monoclonal alloantibodies belonging to the IgM isotype (among the 11 cross-reacting mAbs 10 were IgM). The cross-reactivities of these monoclonal antibodies were ascertained by absorption of alloreacting antibodies with red blood cells. Similar results were obtained on a panel of purified cellular antigens by ELISA. The results confirm that during an immune response against a foreign antigen (alloantigen), B cells that produce polyreactive antibodies are not excluded from the pool of responding cells. Therefore, polyreactive autoantibodies present in sera from healthy individuals may be the result of an immune response against foreign antigens.

Antibodies, Monoclonal↗
PubMed1990

Cytomegalovirus-specific B cell activation as a potential marker for the diagnosis of cytomegalovirus infection.

In vitro secretion of antibodies to cytomegalovirus was investigated by analysis of peripheral blood mononuclear cell culture supernatants from subjects infected with cytomegalovirus. Patients with primary or recurrent cytomegalovirus infection showed transient in vitro cytomegalovirus-specific antibody secretion. A high proportion of patients infected with human immunodeficiency virus and sero-positive for cytomegalovirus showed in vitro cytomegalovirus-specific antibody secretion. All peripheral blood mononuclear cell cultures from patients with symptomatic human immunodeficiency virus infection were found to secrete in vitro antibodies to cytomegalovirus, despite the fact that isolation of cytomegalovirus from some of these patients was not achieved. In human immunodeficiency virus-infected patients, in vitro secretion of anti-cytomegalovirus antibodies appeared to be persistent. In vitro cytomegalovirus-specific antibody secretion by peripheral blood lymphocytes probably reflects an in vitro cytomegalovirus-specific B cell activation. This new assay could be considered an interesting method for detecting both acute or chronic cytomegalovirus infection, with potential use in routine laboratory practice.

Adult↗