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Dive into the research topics where Alexandra Ducancelle is active.

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Featured researches published by Alexandra Ducancelle.


Journal of Clinical Microbiology | 2007

Human Papillomavirus Quantification in Urine and Cervical Samples by Using the Mx4000 and LightCycler General Real-Time PCR Systems

Christopher Payan; Alexandra Ducancelle; Mohamed H. Aboubaker; Julien Caer; Malena Tapia; Amelie Chauvin; Damien Peyronnet; Elodie Le Hen; Zohra Arab; Marie-Christine Legrand; Adissa Tran; E. Postec; Françoise Tourmen; Martine Avenel; Chantal Malbois; Marie-Anne De Brux; Philippe Descamps; Françoise Lunel

ABSTRACT During the last decade, growing efforts have focused on human papillomavirus (HPV) detection using liquid hybridization, conventional PCR, and real-time PCR-based methods to increase the overall proportion of patients participating in cervical cancer screening procedures. We proposed a new general HPV DNA real-time PCR on the Mx4000 (Stratagene) and LightCycler (Roche Diagnostics) systems usable for both cervical scrape specimens and urine samples. A linear range was obtained from 5 DNA copies to 8 log10 DNA copies/ml, and intra- and interassay variations were between 1.8 and 4%. Cervical carcinoma and HPV DNA screening was performed in 333 individual women referred for gynecological examination at the university hospitals of Angers and Brest and enrolled in the PapU study. Among cervical specimens (n = 333), 45% were positive for HPV DNA, with a mean viral load at 5.00 log/ml (± 1.73). Among urine samples (n = 177), 37% were positive with a significant 50-fold-lower mean viral load (3.77 ± 1.32 log/ml; P < 0.0001). Kappa agreement for HPV DNA between cervical and urine specimens was excellent (93%). Thus, we developed a highly sensitive and quantitative general HPV DNA real-time PCR method that allows mass screening of patients with HPV infection. The ongoing longitudinal and prospective multicenter PapU study should give us the opportunity to validate this method adapted to HPV DNA screening in urine samples in a larger population.


Journal of Medical Virology | 2012

Prevalence, risk factors, and molecular epidemiology of hepatitis B and hepatitis delta virus in pregnant women and in patients in Mauritania.

Wael Mansour; F Zahra Fall Malick; Ahmad Sidiya; Mariama Abdou Chekaraou; Pascal Veillon; Alexandra Ducancelle; Ségolène Brichler; Frédéric Le Gal; Baidy Lo; Emmanuel Gordien; Françoise Lunel-Fabiani

No recent data are available on hepatitis B virus (HBV) and hepatitis Delta virus (HDV) prevalence in Mauritania. One thousand twenty pregnant women and 946 patients visiting for routine checkups were screened for HBV and HDV infection. Demographic, epidemiological, ethnic, clinical, and biological data were recorded. HBV and HDV genotypes were determined by sequencing and phylogenetic analyses. In the pregnant women and patients cohorts, respectively, the prevalence of HBsAg (10.7% and 18.3%) and anti‐HBcAb (66.3% and 76.5%) indicated high HBV endemicity. In pregnant women, exposure to HBV was significantly associated in multivariate analysis with education level, ethnicity, blood transfusion, and occupation. HDV antibodies (HDVAb) were found in 14.7% of pregnant women. In patients, HBsAg was found less frequently in females than in males. Again in multivariate analysis, exposure to HBV was significantly correlated with gender (males), and HDVAb positivity with age and gender. The HBV DNA viral load was >3 log IU/ml in only 10.1% of pregnant women and in 17.3% of patients. HDV‐RNA was detectable in 21 (67.7%) of the 31 patients positive for HDVAb, and in 11 of the 16 pregnant women positive for HDVAb (68.8%). The most frequent HBV genotypes were: HBV/D, 53%; HBV/E, 35%; and HBV/A, 12%. Sub‐genotyping revealed HBV/D1,/D7, and the recently described/D8. HDV genotypes were: HDV‐1, 90.3% and HDV‐5, 9.7%. This study confirms the high prevalence of HBV and HDV infections in Mauritania and demonstrates the high genetic diversity of HBV in this country. J. Med. Virol. 84: 1186–1198, 2012.


Antimicrobial Agents and Chemotherapy | 2004

Natural Polymorphism of Cytomegalovirus DNA Polymerase Lies in Two Nonconserved Regions Located between Domains Delta-C and II and between Domains III and I

Anne-Marie Fillet; Laetitia Auray; Sophie Alain; Karine Gourlain; Berthe Marie Imbert; Fatiha Najioullah; Gaël Champier; Stéphanie Gouarin; Jocelyne Carquin; Nadhira Houhou; Isabelle Garrigue; Alexandra Ducancelle; Danielle Thouvenot; Marie-Christine Mazeron

ABSTRACT We described the natural polymorphism of cytomegalovirus DNA polymerase in 42 unrelated isolates susceptible to ganciclovir, foscarnet, and cidofovir. All variations, including an eight-amino-acid deletion, were located between domains delta-C and II and between domains III and I, suggesting that these specific residues are not involved in enzymatic functions.


Journal of Clinical Virology | 2004

Comparison of sequential cytomegalovirus isolates in a patient with lymphoma and failing antiviral therapy

Alexandra Ducancelle; Stéphanie Belloc; Sophie Alain; Catherine Scieux; Marion Malphettes; Françoise Petit; Jean-Claude Brouet; Marie-José Sanson-Le Pors; Marie-Christine Mazeron

BACKGROUND Long-term anti-cytomegalovirus (CMV) treatments in immunocompromised patients are hampered by resistance to antiviral drugs. Longitudinal changes in the resistance genotype may depend on changes in selective pressure and the complexity of CMV isolates. OBJECTIVE To evaluate longitudinal changes in the CMV resistance genotype and phenotype along with strain-specific variability in a patient with non-Hodgkins lymphoma in whom successive anti-CMV treatments failed. STUDY DESIGN The resistance phenotype and genotype of seven CMV isolates collected from one patient during a 2-year follow-up period were retrospectively analysed. In parallel, we used glycoprotein B (gB) genotyping, and a- and UL10-13-sequence analysis to study CMV interstrain variability. RESULTS The patient was infected by at least three CMV strains plus variants of the parental strains. Resistance to ganciclovir, cidofovir and foscarnet was successively detected during the follow-up period. UL97 protein kinase changes responsible for resistance to ganciclovir were initially detected at residues 591 and 592, and then at position 594. Decreased sensitivity to foscarnet coincided with the appearance of amino acid substitution N495K in DNA polymerase, whereas cross-resistance to ganciclovir and cidofovir was due to the L501I substitution. CONCLUSIONS The CMV isolates obtained from our patient were complex mixtures of strains. Changes in resistance genotypes depended on resistance selective pressure and were not linked to interstrain variation.


Clinical Microbiology and Infection | 2010

Venous thrombosis in immunocompetent patients with acute cytomegalovirus infection: a complication that may be underestimated

Pierre Abgueguen; Valérie Delbos; Alexandra Ducancelle; S. Jomaa; Serge Fanello; Eric Pichard

In the present study, we retrospectively studied clinical and laboratory findings associated with cytomegalovirus (CMV) infection in immunocompetent patients. We focused on severe CMV infection. Among 38 patients, five had a severe form of infection: one had meningitis, one had symptomatic thrombocytopenia and three had venous thromboses with pulmonary embolism, a rarely described complication. CMV-induced thrombosis has been reported in immunocompromised patients such as transplant recipients and patients with AIDS. Recent case reports have also described thrombotic phenomena in immunocompetent patients with CMV infection. Our study suggests that venous thrombosis during acute CMV infection is an underestimated complication.


Journal of Clinical Virology | 2012

Virological and epidemiological features of hepatitis delta infection among blood donors in Nouakchott, Mauritania

Wael Mansour; Mohamed-Abdellahi Bollahi; Cheikh-Tijani Hamed; Ségolène Brichler; Frédéric Le Gal; Alexandra Ducancelle; Baidy Lô; Emmanuel Gordien; Michel Rosenheim; Françoise Lunel

BACKGROUND In Mauritania, some authors have described a possible high prevalence of hepatitis delta virus (HDV) infection in the 1990s in studies of small-size samples. OBJECTIVES The aims of our study were to assess the prevalence of HDV in HBsAg positive blood donors in Mauritania, to identify the main risk factors for HDV transmission and to analyze genetic diversity of HDV strains. STUDY DESIGN From October 2008 to December 2009, 11,100 consecutive blood donors were considered in this study. Among them, 1700 (15.3%) were HBsAg positive and 455 accepted to participate in this study. Demographic, epidemiological, ethnical, clinical and biological data were recorded. HDV screening, i.e., antibodies (HDVAb) and RNA (HDV-RNA) detection, was performed for all of them as well as HDV and HBV genotyping. RESULTS Ninety/455 (19.78%) donors were HDVAb positive and HDV-RNA was detectable in 56 (62.2%) of them. HDV infection was significantly associated with older age, number of marriages, military profession, residence in the desert and a history of hospitalization. The HDV genotypes of the circulating strains were HDV-1 (89.3%) and HDV-5 (10.7%). CONCLUSION HDV is highly endemic in Mauritanian blood donors indicating that a high number of them will develop chronic hepatitis, cirrhosis or hepatocellular carcinoma. Associated risk factors support nosocomial transmission of HDV. These data underline the need to reinforce HBV vaccination in newborns and in blood donors without HBV markers, together with screening for HDV in HBV-infected individuals.


Liver International | 2014

Improved fibrosis staging by elastometry and blood test in chronic hepatitis C

Paul Calès; Jérôme Boursier; Alexandra Ducancelle; Frédéric Oberti; I. Hubert; Gilles Hunault; Victor de Ledinghen; Jean-Pierre Zarski; Dominique Salmon; Françoise Lunel

Our main objective was to improve non‐invasive fibrosis staging accuracy by resolving the limits of previous methods via new test combinations. Our secondary objectives were to improve staging precision, by developing a detailed fibrosis classification, and reliability (personalized accuracy) determination.


Journal of Clinical Virology | 2010

Resolution of chronic hepatitis Delta after 1 year of combined therapy with pegylated interferon, tenofovir and emtricitabine.

Wael Mansour; Alexandra Ducancelle; Frédéric Le Gal; Hélène Le Guillou-Guillemette; Pierre Abgueguen; A. Pivert; Paul Calès; Emmanuel Gordien; Françoise Lunel

BACKGROUND Hepatitis Delta virus (HDV) Infection has a worldwide distribution, with approximately 20 millions infected persons. Interferon (IFN) is the only approved drug for the treatment of HDV infection which is still a difficult to treat disease. OBJECTIVES To report a successful treatment of a patient with a chronic severe hepatitis Delta using combination therapy with Pegylated interferon (PegIFN), Tenofovir disoproxil fumarate (TDF) and Emtricitabine (FTC). STUDY DESIGN The patient, a 47 years -old male patient, originating from Dagestan (East Asia), suffered of chronic hepatitis Delta infection. The patient was HBsAg, HBeAg, and anti-Delta Ab (IgG) positive. Serum HBV-DNA level was elevated (more than 9 log UI/mL). Serum HDV-RNA level was up to 5.6 log (copies/ml). Genotypes HBV/D and HDV-1 were demonstrated. The liver histology revealed chronic active hepatitis (Metavir score: A2F2). The treatment was started with PegIFN (180 microg/week) for two months and then TDF (300 mg/day) (combined later with FTC) was added. RESULTS Sustained response was obtained after 10 months of treatment and was accompanied by the clearance of serum hepatitis B virus surface antigen with seroconversion to anti-HBs. CONCLUSION This case report suggests that Delta infection may co-exist with high replicative HBV infection and that combination therapy with PegIFN and nucleoside/tide analogues seems to be more effective than IFN alone. Given that only a single case is reported, further studies including more patients are warranted.


Joint Bone Spine | 2014

Systemic diseases and biotherapies: Understanding, evaluating, and preventing the risk of hepatitis B reactivation

Françoise Lunel-Fabiani; Charles Masson; Alexandra Ducancelle

Hepatitis B virus (HBV) reactivation can occur in chronic carriers of the HBV surface antigen (HBsAg) and constitutes a well-known complication of immunosuppressive therapy. HBV reactivation has also been reported after contact with the HBV. The increasing use of biological agents (TNFα antagonists, rituximab, abatacept, and tocilizumab) to treat systemic diseases has resulted in numerous publications about the risk of HBV reactivation. The relevant scientific societies have issued recommendations designed to prevent HBV reactivation. The main measures consist of screening for markers indicating chronic HBV infection (HBsAg) or HBV infection in the distant past (antibodies to the HBV core antigen) before initiating biological therapies, vaccinating marker-negative patients, and considering close follow-up or antiviral treatment before immunosuppressive treatment initiation or in the event of HBV reactivation. Here, we discuss the pathophysiological mechanisms underlying HBV reactivation during biological treatments, most notably in patients with occult HBV infection or markers for remote HBV infection, whose hepatocyte nuclei may contain a resistance form of HBV DNA known as covalently closed circular DNA (cccDNA). Assessment of the risk of reactivation relies on the HBV status, drugs used, and data from the literature. Finally, we discuss the various recommendations and modalities for HBV vaccination, preemptive treatment, and patient management, according to the level of risk and to the circumstances in which reactivation occurs.


Journal of Infection | 2015

Home-based urinary HPV DNA testing in women who do not attend cervical cancer screening clinics.

Alexandra Ducancelle; Justine Reiser; A. Pivert; Hélène Le Guillou-Guillemette; Anne Sophie Le Duc-Banaszuk; Françoise Lunel-Fabiani

In France, cervical cancer screening is currently based on cytological examination of a Pap smear for women aged 25 to 65, but screening coverage is unsatisfactory. Previous studies have shown that self-sampling for human papillomavirus (HPV) testing increases rates of compliance. With this purpose in mind, we performed the CapU study to evaluate the acceptance of a urinary HPV test. Letters proposing a new cervical cancer screening method using at-home urine self-sampling were sent to 5000 women aged 40-65 years who had not had a Pap smear over the past three years. The participating patients had to send their urine samples to the Angers Hospital Virology Laboratory for analysis using real-time PCR. Of the 771 samples received, 687 were analyzed. High-risk HPV were detected in 29 women. In follow-up, 28 women with positive urinary HPV results had a Pap smear or colposcopy done. The cytological results showed nine abnormal Pap smears, among which histology studies confirmed three cases of cervical intraepithelial neoplasia grade III lesions. Our study shows that urinary HPV testing may be pertinent to women who do not have cervical Pap smears done and lead to the diagnosis of high-grade cervical lesions.

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