21 results on '"Charles HE"'
Search Results
2. Boot camp approach to surgical residency preparation: feedback from a French university hospital
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Etienne Buscail, Fabrice Muscari, Aurélien Hostalrich, Manon Bolzinger, Sandra Malavaud, Vincent Minville, Charlotte Martin, Magali Delhoste, Charles Henri Houze-Cerfon, Simon Buscail, Bruno Bastiani, Mathieu Roumiguié, Ariane Weyl, Nicolas Carrère, and Olivier Abbo
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Education ,Surgery ,Video-based learning ,Surgical residency program in France ,Surgical skills ,Curriculum design ,Special aspects of education ,LC8-6691 ,Medicine - Abstract
Abstract Introduction The transition from medical student to surgical resident is not a simple one. The aim of this study was to report the experience of a university hospital in the organization of the induction course for future surgical residents and the contribution of a video support in the learning of the suture. Material and method We were able to study two consecutive years of students (October 2020 and 2021). Concerning the practical and technical workshops (learning suture) we carried out a comparative study between two groups of students. A group that had video support for learning suture (video group) and a group without video (control group). The evaluation of the suture was performed in a blinded manner by two supervising surgeons. The other practical workshop was drain fixation; the students did not have a video for this workshop. A comparative study was also performed for the drain fixation workshop between the two groups (video group and control group). A program of theoretical courses was also set up. This program is established according to the different future functions of the residents by integrating medico-legal notions and teamwork. Satisfaction questionnaires were given to the students and the answers were given two months after taking up their duties in the hospital (6 questions with Likert scale and 4 free questions). Results The cohort consisted of 58 students (29 each in 2020 and 29 in 2021). Comparative analyses of the evaluation of the suture workshops showed better performance in the video group compared with the group without video. The comparison of these two groups did not show significant differences in the drain fixation workshop. The theoretical teaching was broken down according to the students' future tasks and each speaker was a specialist in his or her field of expertise. The results of the questionnaires showed a desire on the part of the students to increase the time spent on practical workshops and theoretical forensic teaching. Conclusion We were able to show through these two years of a program that we were able to offer a surgical resident preparation course. In addition, we have highlighted the contribution of a video support in the learning curve of the suture.
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- 2022
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3. Evaluation of the effect of sodium zirconium cyclosilicate on arrhythmia-related cardiovascular outcomes in patients receiving chronic haemodialysis with hyperkalaemia: protocol for the multicentre, randomised, controlled DIALIZE-Outcomes study
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Michel Jadoul, Steven Fishbane, Laura Dember, CP Kovesdy, Ayman Al-Shurbaji, Vera Lisovskaja, Priya Sekar, Brian Katona, Nicolas Guzman, and Charles Herzog
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Medicine - Abstract
Introduction Patients with kidney failure receiving chronic haemodialysis have elevated risk of arrhythmias potentially increasing the likelihood of sudden cardiac death, stroke and hospitalisation. The DIALIZE study (NCT03303521) demonstrated that sodium zirconium cyclosilicate (SZC) was an efficacious and well-tolerated treatment for predialysis hyperkalaemia in patients undergoing haemodialysis. The DIALIZE-Outcomes study evaluates the effect of SZC on sudden cardiac death and arrhythmia-related cardiovascular outcomes in patients receiving chronic haemodialysis with recurrent hyperkalaemia.Methods and analysis International, multicentre, randomised, double-blind, placebo-controlled study conducted at 357 study sites across 25 countries. Adults (≥18 years) receiving chronic haemodialysis three times per week with recurrent predialysis serum potassium (K+) ≥5.5 mmol/L post long interdialytic interval (LIDI) are eligible. Patients (~2800) will be randomised 1:1 to SZC or placebo, starting at 5 g orally once daily on non-dialysis days and titrated weekly in 5 g increments (maximum 15 g) to target predialysis serum K+ 4.0–5.0 mmol/L post LIDI. The primary objective is to evaluate efficacy of SZC versus placebo in reducing occurrence of the primary composite endpoint of sudden cardiac death, stroke or arrhythmia-related hospitalisation, intervention or emergency department visit. Secondary endpoints include efficacy of SZC versus placebo in maintaining normokalaemia (serum K+ 4.0–5.5 mmol/L post LIDI) at the 12-month visit, preventing severe hyperkalaemia (serum K+ ≥6.5 mmol/L post LIDI) at the 12-month visit and reducing the incidence of individual cardiovascular outcomes. Safety of SZC will be evaluated. The study is event driven, with participants remaining in the study until 770 primary endpoint events have occurred. Average time in the study is expected to be ~25 months.Ethics and dissemination Approval was obtained from the relevant institutional review board/independent ethics committee from each participating site (approving bodies in supplementary information). The results will be submitted to a peer-reviewed journal.Trial registration numbers EudraCT 2020-005561-14 and clinicaltrials.gov identifier NCT04847232.
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- 2023
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4. Hubble Space Telescope Metallized Teflon ® FEP thermal Control Materials: On-Orbit Degradation and Post-Retrieval Analysis
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Patricia A. Hansen, Len Wang, Joyce A. Dever, Jacqueline A. Townsend, Charles He, Bruce A. Banks, and Kim K. de Groh
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Materials science ,Polymers and Plastics ,02 engineering and technology ,Temperature cycling ,Radiation ,medicine.disease_cause ,law.invention ,Telescope ,chemistry.chemical_compound ,Fluorinated ethylene propylene ,Optics ,020401 chemical engineering ,law ,Shield ,Materials Chemistry ,medicine ,0204 chemical engineering ,Stress concentration ,business.industry ,Organic Chemistry ,021001 nanoscience & nanotechnology ,chemistry ,0210 nano-technology ,business ,Layer (electronics) ,Ultraviolet - Abstract
During the Hubble Space Telescope (HST) second servicing mission (SM2), degradation of unsupported Teflon® FEP (fluorinated ethylene propylene), used as the outer layer of the multilayer insulation (MLI) blankets, was evident as large cracks on the telescope light shield. A sample of the degraded outer layer was retrieved during the mission and returned to Earth for ground testing and evaluation. The results of the Teflon® FEP sample evaluation and additional testing of pristine Teflon® FEP led the investigative team to theorize that the HST damage was caused by thermal cycling with deep-layer damage from electron and proton radiation which allowed the propagation of cracks along stress concentrations, and that the damage increased with the combined total dose of electrons, protons, ultraviolet and x-ray radiation along with thermal cycling. This paper discusses the testing and evaluation of the retrieved Teflon® FEP.
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- 1999
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5. Investigating transmission of SARS-CoV-2 using novel face mask sampling: a protocol for an observational prospective study of index cases and their contacts in a congregate setting
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Daniel Olson, Stephanie James, Thomas Jaenisch, Stephen Berman, Molly M Lamb, Emily N Gallichotte, Brian Adams, Charles Henry, Jeannine Riess, Joni Triantis van Sickle, Kellie L Hawkins, Brian T Montague, Cody Coburn, Leisha Conners Bauer, Jennifer Kovarik, Mark T Hernandez, Amy Bronson, Lucy Graham, Stephanie Hanenberg, James Kovacs, John S Spencer, Mark Zabel, Philip D Fox, Olivia Pluss, William Windsor, Geoffrey Winstanley, Michael Barer, Gregory Ebel, and May Chu
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Medicine - Abstract
Introduction This study aims to measure how transmission of SARS-CoV-2 occurs in communities and to identify conditions that lend to increased transmission focusing on congregate situations. We will measure SARS-CoV-2 in exhaled breath of asymptomatic and symptomatic persons using face mask sampling—a non-invasive method for SARS-CoV-2 detection in exhaled air. We aim to detect transmission clusters and identify risk factors for SARS-CoV-2 transmission in presymptomatic, asymptomatic and symptomatic individuals.Methods and analysis In this observational prospective study with daily follow-up, index cases and their respective contacts are identified at each participating institution. Contact definitions are based on Centers for Disease Control and Prevention and local health department guidelines. Participants will wear masks with polyvinyl alcohol test strips adhered to the inside for 2 hours daily. The strips are applied to all masks used over at least 7 days. In addition, self-administered nasal swabs and (optional) finger prick blood samples are performed by participants. Samples are tested by standard PCR protocols and by novel antigen tests.Ethics and dissemination This study was approved by the Colorado Multiple Institutional Review Board and the WHO Ethics Review Committee. From the data generated, we will analyse transmission clusters and risk factors for transmission of SARS-CoV-2 in congregate settings. The kinetics of asymptomatic transmission and the evaluation of non-invasive tools for detection of transmissibility are of crucial importance for the development of more targeted control interventions—and ultimately to assist with keeping congregate settings open that are essential for our social fabric.Trial registration number ClinicalTrials.gov (#NCT05145803).
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- 2022
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6. Agranulocytosis‐complicated DRESS with medullar HHV‐6 replication
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Margot Lehericey, Florence Tétart, Priscille Carvalho, Olivia Bauvin, Charles Hervouet, Pascal Joly, and Vivien Hébert
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agranulocytosis ,bone marrow ,drug reaction with eosinophilia and systemic symptoms ,HHV‐6 ,Medicine ,Medicine (General) ,R5-920 - Abstract
Abstract HHV‐6B is the subtype most often involved in the systemic manifestations of the DRESS, but also in myelosuppression in bone marrow transplant. We report a new observation of its myelosuppressive effect: a case of DRESS complicated by agranulocytosis with detectable HHV‐6 RNA in bone marrow.
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- 2020
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7. What really impacts the use of active learning in undergraduate STEM education? Results from a national survey of chemistry, mathematics, and physics instructors.
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Naneh Apkarian, Charles Henderson, Marilyne Stains, Jeffrey Raker, Estrella Johnson, and Melissa Dancy
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Medicine ,Science - Abstract
Six common beliefs about the usage of active learning in introductory STEM courses are investigated using survey data from 3769 instructors. Three beliefs focus on contextual factors: class size, classroom setup, and teaching evaluations; three focus on individual factors: security of employment, research activity, and prior exposure. The analysis indicates that instructors in all situations can and do employ active learning in their courses. However, with the exception of security of employment, trends in the data are consistent with beliefs about the impact of these factors on usage of active learning. We discuss implications of these results for institutional and departmental policies to facilitate the use of active learning.
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- 2021
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8. Besoins en réinsertion psycho-sociale et économique des patientes opérées de fistule vésico-vaginale au Cameroun
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Pierre Marie Tebeu, Jean Pierre Kamga Olen, Estelle Carine Ngoula Zeck, Jesse Saint Saba Antaon, Charlemagne Simplice Moukouta, and Charles Henry Rochat
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fistule obstétricale ,réintégration ,économie ,caractéristiques ,psychosocial ,Medicine - Abstract
Introduction: la fistule obstétricale est une communication anormale entre le vagin et la vessie et/ou le rectum par la quelle les urines et/ou les matières fécales coulent constamment. Beaucoup de femmes présentant cette pathologie ont tendance à penser à se cacher et à se suicider. L´objectif de cette étude était d´étudier les besoins en réinsertion psychosociale des patientes opérées de fistule vésico-vaginale. Méthodes: nous avons conduit une étude transversale descriptive dans deux hôpitaux de références en matière de prise en charge de la fistule obstétricale au Cameroun : l´Hôpital Protestant de Ngaoundéré et le Centre Hospitalier et Universitaire de Yaoundé. L´étude a été faite sur une durée de 9 mois (octobre 2016 à juin 2017). Toutes les femmes présentant une Fistule vésico-vaginale (FVV) étaient incluses. Parmi elles nous avons exclu celles qui n´avaient pas donné leur consentement éclairé. Les proportions ont été calculées à l´aide du logiciel EPI info version 7.1.3.3. Les effectifs et les pourcentages ont été calculés pour les variables qualitatives et les moyennes et les écarts types pour les variables quantitatives. Résultats: l´âge de la population variait de 17 à 48 ans avec une moyenne de 32,13 ± 8,03 ans. Parmi les 50 patientes, 37 (74%) avaient rapporté le décès du nouveau-né à la grossesse causale et 4 sur les 24 (16,66%) qui avaient un travail avant la fistule avaient été contraintes de l´abandonner. Les besoins psychologiques non couverts étaient dominés par la paucité de counseling focalisé en cas du décès 5/37 (13,5%), la paucité du counseling en cas d´abandon par la famille/conjoint, 9/28 (32,1%), la paucité du counseling spécifique en cas d´idée suicidaire 2/16 (12,5%) et l´absence de prise en charge des patientes avec anxiété/dépression. Sur le plan social, les besoins non couverts étaient dominés par la paucité dans l´intégration d´une association, 21/50 (42%). Sur le plan économique, ils étaient dominés par l´absence d´activité génératrice de revenu particulièrement chez toutes les 26 femmes initialement sans emploi et chez les 4 femmes qui ont perdu leur emploi à cause de la fistule. Conclusion: les besoins psycho-sociaux non couverts sont dominés par l´absence de counseling focalisé sur la condition spécifique de chaque femme, la faible proportion d´intégration d´une association et l´absence d´activité génératrice de revenu.
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- 2020
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9. Hypoglycemic Toxins and Enteroviruses as Causes of Outbreaks of Acute Encephalitis-Like Syndrome in Children, Bac Giang Province, Northern Vietnam
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Nga Thi Phan, Meriadeg Ar Gouilh, Juliette Paireau, Loan Phuong, Justine Cheval, Nghia Duy Ngu, Charles Hébert, Tuan Hai Nguyen, Olivier Lortholary, Laura Tondeur, Jean-Claude Manuguerra, Robert Barouki, Johannes Sander, Nils Janzen, Hien Tran Nguyen, Paul T. Brey, Arnaud Fontanet, and Marc Eloit
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hypoglycemic toxins ,enteroviruses ,viruses ,meningitis/encephalitis ,encephalitis ,acute encephalitis syndrome ,Medicine ,Infectious and parasitic diseases ,RC109-216 - Abstract
We investigated the cause of seasonal outbreaks of pediatric acute encephalitis-like syndrome associated with litchi harvests (May–July) in northern Vietnam since 2008. Nineteen cerebrospinal fluid samples were positive for human enterovirus B, and 8 blood samples were positive for hypoglycemic toxins present in litchi fruits. Patients who were positive for hypoglycemic toxins had shorter median times between disease onset and admission, more reports of seizures, more reports of hypoglycemia (glucose level
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- 2018
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10. Pixel: a content management platform for quantitative omics data
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Thomas Denecker, William Durand, Julien Maupetit, Charles Hébert, Jean-Michel Camadro, Pierre Poulain, and Gaëlle Lelandais
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Data cycle analyses ,Omics ,Open source ,Pixel Web App ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
Background In biology, high-throughput experimental technologies, also referred as “omics” technologies, are increasingly used in research laboratories. Several thousands of gene expression measurements can be obtained in a single experiment. Researchers are routinely facing the challenge to annotate, store, explore and mine all the biological information they have at their disposal. We present here the Pixel web application (Pixel Web App), an original content management platform to help people involved in a multi-omics biological project. Methods The Pixel Web App is built with open source technologies and hosted on the collaborative development platform GitHub (https://github.com/Candihub/pixel). It is written in Python using the Django framework and stores all the data in a PostgreSQL database. It is developed in the open and licensed under the BSD 3-clause license. The Pixel Web App is also heavily tested with both unit and functional tests, a strong code coverage and continuous integration provided by CircleCI. To ease the development and the deployment of the Pixel Web App, Docker and Docker Compose are used to bundle the application as well as its dependencies. Results The Pixel Web App offers researchers an intuitive way to annotate, store, explore and mine their multi-omics results. It can be installed on a personal computer or on a server to fit the needs of many users. In addition, anyone can enhance the application to better suit their needs, either by contributing directly on GitHub (encouraged) or by extending Pixel on their own. The Pixel Web App does not provide any computational programs to analyze the data. Still, it helps to rapidly explore and mine existing results and holds a strategic position in the management of research data.
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- 2019
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11. Is the discopathy associated with Modic changes an infectious process? Results from a prospective monocenter study.
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Salim Ahmed-Yahia, Jean-Winoc Decousser, Charles Henri Flouzat-Lachaniette, Guillaume Dervin, François Roubineau, Etienne Audureau, Alexia Hourdille, Guilhem Royer, Florent Eymard, and Xavier Chevalier
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Medicine ,Science - Abstract
BackgroundThe local infectious origin and the putative role of Cutibacterium acnes (CA) of a particular subtype of discopathy (Modic 1) are still debated.PurposeTo establish the association of CA in intervertebral disc (IVD) and Modic 1 discopathy in patients with low back pain.MethodsThe prevalence of bacteria in IVD samples obtained by anterior approach in patient with chronic low back pain harboring Modic type 1, 2 or no Modic changes was compared to that measured in IVD samples obtained by posterior approach for sciatica. From 45 patients included in the study, 77 discs samples were obtained: 58 by anterior approach (32 Modic 1/2 changes, 26 without Modic change) and 19 by posterior approach. Conventional microbial cultures, universal 16S rRNA molecular detection and a CA specific PCR were performed.Results12 /77 (15.6%) disc samples were culture positive. Among the 10 CA positive cultures, 5 out of 58 (8.6%) were identified from specimens obtained by anterior approach and 5/19 (26.3%) from posterior approach (p = 0.046). Moreover, the percentage of CA culture positive sample was statistically no different between the patient with or without Modic changes. The CA prevalence was lower through molecular, culture-free approaches: the universal 16S rRNA PCR was positive for 6 specimens, including one CA positive sample and the CA specific PCR was positive for one specimen obtained by posterior approach.ConclusionsIn spine surgery the prevalence of CA in culture was significantly higher in IVD samples collected through a posterior approach compared to an anterior approach, suggesting a contamination process. This study did not support the CA related local infectious origin of Modic 1 discopathy.
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- 2019
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12. The heparan sulfate 3-O-sulfotransferases (HS3ST) 2, 3B and 4 enhance proliferation and survival in breast cancer MDA-MB-231 cells.
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Charles Hellec, Maxime Delos, Mathieu Carpentier, Agnès Denys, and Fabrice Allain
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Medicine ,Science - Abstract
Heparan sulfate 3-O-sulfotransferases (HS3STs) catalyze the final maturation step of heparan sulfates. Although seven HS3ST isozymes have been described in human, 3-O-sulfation is a relatively rare modification, and only a few biological processes have been described to be influenced by 3-O-sulfated motifs. A conflicting literature has recently reported that HS3ST2, 3A, 3B and 4 may exhibit either tumor-promoting or anti-oncogenic properties, depending on the model used and cancer cell phenotype. Hence, we decided to compare the consequences of the overexpression of each of these HS3STs in the same cellular model. We demonstrated that, unlike HS3ST3A, the other three isozymes enhanced the proliferation of breast cancer MDA-MB-231 and BT-20 cells. Moreover, the colony forming capacity of MDA-MB-231 cells was markedly increased by the expression of HS3ST2, 3B and 4. No notable difference was observed between the three isozymes, meaning that the modifications catalyzed by each HS3ST had the same functional impact on cell behavior. We then demonstrated that overexpression of HS3ST2, 3B and 4 was accompanied by increased activation of c-Src, Akt and NF-κB and up-regulation of the anti-apoptotic proteins survivin and XIAP. In line with these findings, we showed that HS3ST-transfected cells are more resistant to cell death induction by pro-apoptotic stimuli or NK cells. Altogether, our findings demonstrate that HS3ST2, 3B and 4 share the same pro-tumoral activity and support the idea that these HS3STs could compensate each other for loss of their expression depending on the molecular signature of cancer cells and/or changes in the tumor environment.
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- 2018
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13. The pattern of non-obstetric fistula: A Cameroonian experience
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Pierre-Marie Tebeu, Eric Brice Touka, Yvette Mawamba, Calvin Tiyou, Joseph Nelson Fomulu, and Charles Henry Rochat
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Non-obstetrical genital fistula ,Uro-genital fistula ,Genito-digestive fistula ,Medicine - Abstract
Objective: To investigate the pattern of Non-obstetrical genital fistula (NOGF) in Cameroonian context. Materials and methods: This was a cross-sectional analytic study, with two groups of patients, including those treated for non-obstetrical fistula as subject, and their obstetrical counterparts as the control. Data were retrieved from the obstetric fistula database of the Department of Obstetrics and Gynecology in the University Teaching Hospital of Yaoundé Cameroon for patients operated from January, 1, 2009 to December 31, 2012. Results: NOGF represented 19.78% of genital fistula. Uro-genital fistula (UGF) represented 72.20% while non-obstetrical genito-digestive fistula (GDF) represented 27.80% of NOGF. The main cause of UGF was hysterectomy (46.15%) while the main cause of genito-digestive fistula was vaginal infections (40.00%). Most patients had never been operated before their arrival in the YUTH (84.60% for UGF and 60.00% for GDF). We had one failure at first surgical attempt. Conclusion: UGF fistula is the main type of NOGF in Cameroonian context, with hysterectomy being the leading cause. Proper knowledge on NOGF will enable better strategies to fight against genital fistula.
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- 2014
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14. Siglec receptors impact mammalian lifespan by modulating oxidative stress
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Flavio Schwarz, Oliver MT Pearce, Xiaoxia Wang, Annie N Samraj, Heinz Läubli, Javier O Garcia, Hongqiao Lin, Xiaoming Fu, Andrea Garcia-Bingman, Patrick Secrest, Casey E Romanoski, Charles Heyser, Christopher K Glass, Stanley L Hazen, Nissi Varki, Ajit Varki, and Pascal Gagneux
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inflammation ,reactive oxygen species ,aging ,Siglec ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
Aging is a multifactorial process that includes the lifelong accumulation of molecular damage, leading to age-related frailty, disability and disease, and eventually death. In this study, we report evidence of a significant correlation between the number of genes encoding the immunomodulatory CD33-related sialic acid-binding immunoglobulin-like receptors (CD33rSiglecs) and maximum lifespan in mammals. In keeping with this, we show that mice lacking Siglec-E, the main member of the CD33rSiglec family, exhibit reduced survival. Removal of Siglec-E causes the development of exaggerated signs of aging at the molecular, structural, and cognitive level. We found that accelerated aging was related both to an unbalanced ROS metabolism, and to a secondary impairment in detoxification of reactive molecules, ultimately leading to increased damage to cellular DNA, proteins, and lipids. Taken together, our data suggest that CD33rSiglecs co-evolved in mammals to achieve a better management of oxidative stress during inflammation, which in turn reduces molecular damage and extends lifespan.
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- 2015
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15. Ixodid and Argasid Tick Species and West Nile Virus
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Charles Henderson Lawrie, Nathalie Yumari Uzcátegui, Ernest Andrew Gould, and Patricia Anne Nuttall
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West Nile virus ,virus ,ticks ,Ixodidae,Argasidae,transmission,co-feedingtransmission. ,Medicine ,Infectious and parasitic diseases ,RC109-216 - Abstract
Control of West Nile virus (WNV) can only be effective if the vectors and reservoirs of the virus are identified and controlled. Although mosquitoes are the primary vectors, WNV has repeatedly been isolated from ticks. Therefore tick-borne transmission studies were performed with an ixodid (Ixodes ricinus) and an argasid tick species (Ornithodoros moubata). Both species became infected after feeding upon viremic hosts, but I. ricinus ticks were unable to maintain the virus. In contrast, O. moubata ticks were infected for at least 132 days, and the infection was maintained through molting and a second bloodmeal. Infected O. moubata ticks transmitted the virus to rodent hosts, albeit at a low level. Moreover, the virus was nonsystemically transmitted between infected and uninfected O. moubata ticks co-fed upon uninfected hosts. Although ticks are unlikely to play a major role in WNV transmission, our findings suggest that some species have the potential to act as reservoirs for the virus.
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- 2004
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16. Next generation sequencing uncovers unexpected bacterial pathogens in ticks in western Europe.
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Muriel Vayssier-Taussat, Sara Moutailler, Lorraine Michelet, Elodie Devillers, Sarah Bonnet, Justine Cheval, Charles Hébert, and Marc Eloit
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Medicine ,Science - Abstract
BACKGROUND AND AIMS: Ticks are highly susceptible to global environmental and socio-economical changes. Several tick-borne pathogens have been reported in new geographical regions while new species, strains or genetic variants of tick-borne microorganisms are continually being detected. However, tick-borne pathogens are still poorly understood, and it is estimated that half of all human tick-borne disease has an unknown origin. Therefore in order to prevent these diseases, more effort is required to identify unknown or unexpected tick-borne pathogens. Ixodes ricinus is the vector for a broad range of bacterial pathogens and the most prevalent tick in Europe. The aim of the present study was to evaluate the capability of Next Generation Sequencing (NGS) to extend the inventory of pathogenic bacteria carried by this species of tick in France. METHODS: RNA and DNA were extracted from 1450 I. ricinus questing nymphs collected by flagging in Alsace, France. RNA was pooled and used for NGS. Following de novo assembly, bacterial contigs were assigned to the closest known taxonomy. DNA was used for real time PCR to confirm taxonomic species assignment of NGS-derived contigs for the doubtful cases, and for determination of prevalence. RESULTS: We have generated a global in-depth picture of tick-borne bacteria. We identified RNA from the main pathogenic bacterial species known to be transmitted by I. ricinus. In addition we also identified unanticipated bacterial species for which we have estimated the prevalence within those ticks inhabiting the studied areas. CONCLUSIONS: The data obtained from this study has proven that NGS has an enormous potential to detect the unexpected and provides the means to monitor pathogen occurrence.
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- 2013
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17. Inactivation of MARCH5 prevents mitochondrial fragmentation and interferes with cell death in a neuronal cell model.
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Lei Fang, Charles Hemion, David Goldblum, Peter Meyer, Selim Orgül, Stephan Frank, Josef Flammer, and Albert Neutzner
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Medicine ,Science - Abstract
To study the impact of the mitochondrial ubiquitin ligase MARCH5 on mitochondrial morphology and induction of apoptosis using an in vitro model of neuronal precursor cells exposed to glaucoma-relevant stress conditions.RGC5 cells transfected with expression constructs for MARCH5, MARCH5(H43W), Dpr1(K38A) or vector control were exposed to either elevated pressure of 30 mmHg, oxidative stress caused by mitochondrial electron transport chain (ETC) inhibition, or hypoxia-reoxygenation conditions. Mitochondrial morphology of RGC5 cells was analyzed following staining of the mitochondrial marker cytochrome c and photoactivatable GFP (PAGFP) diffusion assay. Induction of apoptotic cell death in these cells was determined by analyzing the release of cytochrome c from mitochondria into the cytosol and flow cytometry.Exposure of RGC5 cells to oxidative stress conditions as well as to elevated pressure resulted in the fragmentation of the mitochondrial network in control cells as well as in cells expressing MARCH5. In cells expressing inactive MARCH5(H43W) or inactive Drp(K38A), mitochondrial fragmentation was significantly blocked and mitochondrial morphology was comparable to that of control cells under normal conditions. Exposure of RGC5 cells to elevated pressure or oxidative stress conditions induced apoptotic cell death as assessed by cytochrome c release and DNA staining, while expression of dominant-negative MARCH5(H43W) or Drp1(K38A) did significantly delay cell death.Preventing mitochondrial fragmentation through interference with the mitochondrial fission machinery protects neuronal cells from programmed cell death following exposure to stressors physiologically relevant to the pathogenesis of glaucoma.
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- 2012
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18. Human skin microbiota: high diversity of DNA viruses identified on the human skin by high throughput sequencing.
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Vincent Foulongne, Virginie Sauvage, Charles Hebert, Olivier Dereure, Justine Cheval, Meriadeg Ar Gouilh, Kevin Pariente, Michel Segondy, Ana Burguière, Jean-Claude Manuguerra, Valérie Caro, and Marc Eloit
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Medicine ,Science - Abstract
The human skin is a complex ecosystem that hosts a heterogeneous flora. Until recently, the diversity of the cutaneous microbiota was mainly investigated for bacteria through culture based assays subsequently confirmed by molecular techniques. There are now many evidences that viruses represent a significant part of the cutaneous flora as demonstrated by the asymptomatic carriage of beta and gamma-human papillomaviruses on the healthy skin. Furthermore, it has been recently suggested that some representatives of the Polyomavirus genus might share a similar feature. In the present study, the cutaneous virome of the surface of the normal-appearing skin from five healthy individuals and one patient with Merkel cell carcinoma was investigated through a high throughput metagenomic sequencing approach in an attempt to provide a thorough description of the cutaneous flora, with a particular focus on its viral component. The results emphasize the high diversity of the viral cutaneous flora with multiple polyomaviruses, papillomaviruses and circoviruses being detected on normal-appearing skin. Moreover, this approach resulted in the identification of new Papillomavirus and Circovirus genomes and confirmed a very low level of genetic diversity within human polyomavirus species. Although viruses are generally considered as pathogen agents, our findings support the existence of a complex viral flora present at the surface of healthy-appearing human skin in various individuals. The dynamics and anatomical variations of this skin virome and its variations according to pathological conditions remain to be further studied. The potential involvement of these viruses, alone or in combination, in skin proliferative disorders and oncogenesis is another crucial issue to be elucidated.
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- 2012
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19. Crystal structure of Diedel, a marker of the immune response of Drosophila melanogaster.
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Franck Coste, Cordula Kemp, Vanessa Bobezeau, Charles Hetru, Christine Kellenberger, Jean-Luc Imler, and Alain Roussel
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Medicine ,Science - Abstract
BACKGROUND:The Drosophila melanogaster gene CG11501 is up regulated after a septic injury and was proposed to act as a negative regulator of the JAK/STAT signaling pathway. Diedel, the CG11501 gene product, is a small protein of 115 residues with 10 cysteines. METHODOLOGY/PRINCIPAL FINDINGS:We have produced Diedel in Drosophila S2 cells as an extra cellular protein thanks to its own signal peptide and solved its crystal structure at 1.15 Å resolution by SIRAS using an iodo derivative. Diedel is composed of two sub domains SD1 and SD2. SD1 is made of an antiparallel β-sheet covered by an α-helix and displays a ferredoxin-like fold. SD2 reveals a new protein fold made of loops connected by four disulfide bridges. Further structural analysis identified conserved hydrophobic residues on the surface of Diedel that may constitute a potential binding site. The existence of two conformations, cis and trans, for the proline 52 may be of interest as prolyl peptidyl isomerisation has been shown to play a role in several physiological mechanisms. The genome of D. melanogaster contains two other genes coding for proteins homologous to Diedel, namely CG43228 and CG34329. Strikingly, apart from Drosophila and the pea aphid Acyrthosiphon pisum, Diedel-related sequences were exclusively identified in a few insect DNA viruses of the Baculoviridae and Ascoviridae families. CONCLUSION/SIGNIFICANCE:Diedel, a marker of the Drosophila antimicrobial/antiviral response, is a member of a small family of proteins present in drosophilids, aphids and DNA viruses infecting lepidopterans. Diedel is an extracellular protein composed of two sub-domains. Two special structural features (hydrophobic surface patch and cis/trans conformation for proline 52) may indicate a putative interaction site, and support an extra cellular signaling function for Diedel, which is in accordance with its proposed role as negative regulator of the JAK/STAT signaling pathway.
- Published
- 2012
- Full Text
- View/download PDF
20. Murine GRPR and stathmin control in opposite directions both cued fear extinction and neural activities of the amygdala and prefrontal cortex.
- Author
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Guillaume Martel, Charles Hevi, Alexandra Wong, Ko Zushida, Shusaku Uchida, and Gleb P Shumyatsky
- Subjects
Medicine ,Science - Abstract
Extinction is an integral part of normal healthy fear responses, while it is compromised in several fear-related mental conditions in humans, such as post-traumatic stress disorder (PTSD). Although much research has recently been focused on fear extinction, its molecular and cellular underpinnings are still unclear. The development of animal models for extinction will greatly enhance our approaches to studying its neural circuits and the mechanisms involved. Here, we describe two gene-knockout mouse lines, one with impaired and another with enhanced extinction of learned fear. These mutant mice are based on fear memory-related genes, stathmin and gastrin-releasing peptide receptor (GRPR). Remarkably, both mutant lines showed changes in fear extinction to the cue but not to the context. We performed indirect imaging of neuronal activity on the second day of cued extinction, using immediate-early gene c-Fos. GRPR knockout mice extinguished slower (impaired extinction) than wildtype mice, which was accompanied by an increase in c-Fos activity in the basolateral amygdala and a decrease in the prefrontal cortex. By contrast, stathmin knockout mice extinguished faster (enhanced extinction) and showed a decrease in c-Fos activity in the basolateral amygdala and an increase in the prefrontal cortex. At the same time, c-Fos activity in the dentate gyrus was increased in both mutant lines. These experiments provide genetic evidence that the balance between neuronal activities of the amygdala and prefrontal cortex defines an impairment or facilitation of extinction to the cue while the hippocampus is involved in the context-specificity of extinction.
- Published
- 2012
- Full Text
- View/download PDF
21. Quality care in vesico-vaginal obstetric fistula: case series report from the regional hospital of Maroua-Cameroon
- Author
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Pierre Marie Tebeu, Joseph Nelson Fomulu, Achille Aurelien Mbassi, Jean Marie Tcheliebou, Anderson Sama Doh, and Charles Henry Rochat
- Subjects
Obstetric fistula ,closure ,continence ,Cameroon ,Medicine - Abstract
The World Health Organization (WHO) proposes a successful closure rate for first repair of vesico-vaginal obstetric fistula to be at 85% in each facility, with the continence achievement among the closed cases at 90 %. We are reporting the vesico-vaginal obstetric fistula outcome at the provincial hospital of Maroua-Cameroon from 2005 to August 2007. Among the overall 32 patients with vesico-vaginal fistula operated, 25 patients were at their first operation. The complete closure of vesico-vaginal fistula (VVF) was 23/25 (92%) and among the 23 patients with complete closure 17(74%) had good continence. When we consider only the 25 patients who were at their first operation, the overall closure of VVF was 23/25 (92%) and among them 17/23 (74%) were continent. Large lesion, bladder neck lesions, vaginal adherence and rigid margin are associated with failure/incontinence. These factors must be taken into consideration when preparing patients for surgery or when assigning them to a surgeon within the surgical team
- Published
- 2010
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