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81.
Hepatitis E virus (HEV) is an emerging cause of acute hepatitis in Europe, particularly in southern France, and HEV is a new causative agent of chronic hepatitis and cirrhosis in immunocompromised patients. However, the data regarding HEV infection after kidney transplantation are still scarce with respect to the clinical issues that have been raised, and no study has specifically focused on kidney transplant recipients. This study described the clinical features and outcomes of HEV infections in a cohort of kidney transplant recipients living in southeastern France. The epidemiological, clinical, and virological characteristics of HEV infections diagnosed by PCR over a 53‐month period were retrospectively analyzed in a cohort of 1,350 kidney transplant recipients monitored at the Marseille University Hospital. Sixteen HEV infections were diagnosed, all of which were autochthonous and involved genotype 3 viruses (HEV‐3). Chronic infections occurred in 80% of these patients and resolved in half of the cases after a median time of 39 months. The rate of HEV clearance was 54% after a decrease in the dose of immunosuppressants. One patient developed liver cirrhosis 14 months after infection and experienced acute rejection after a decrease in the dose of immunosuppressants. Autochthonous HEV‐3 infections in kidney transplant recipients progress to chronicity in most cases and might be complicated by early liver cirrhosis. Chronic HEV infection can resolve following the reduction of immunosuppressive therapy, but ribavirin may be required if reduction of the immunosuppressant dose is not associated with HEV clearance or is inappropriate for the patient management. J. Med. Virol. 85:462–471, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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SARS-CoV-2 infection causes an abrupt response by the host immune system, which is largely responsible for the outcome of COVID-19. We investigated whether the specific immune responses in the peripheral blood of 276 patients were associated with the severity and progression of COVID-19. At admission, dramatic lymphopenia of T, B, and NK cells is associated with severity. Conversely, the proportion of B cells, plasmablasts, circulating follicular helper T cells (cTfh) and CD56CD16+ NK-cells increased. Regarding humoral immunity, levels of IgM, IgA, and IgG were unaffected, but when degrees of severity were considered, IgG was lower in severe patients. Compared to healthy donors, complement C3 and C4 protein levels were higher in mild and moderate, but not in severe patients, while the activation peptide of C5 (C5a) increased from the admission in every patient, regardless of their severity. Moreover, total IgG, the IgG1 and IgG3 isotypes, and C4 decreased from day 0 to day 10 in patients who were hospitalized for more than two weeks, but not in patients who were discharged earlier. Our study provides important clues to understand the immune response observed in COVID-19 patients, associating severity with an imbalanced humoral response, and identifying new targets for therapeutic intervention.  相似文献   
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BackgroundThough women increasingly make up the majority of medical-school and other science graduates, they remain a minority in academic biomedical settings, where they are less likely to hold leadership positions or be awarded research funding. A major factor is the career breaks that women disproportionately take to see to familial duties. They experience a related, but overlooked, hurdle upon their return: they are often too old to be eligible for ‘early-career researcher’ grants and ‘career-development’ awards, which are stepping stones to leadership positions in many institutions and which determine the demographics of their hierarchies for decades to come. Though age limits are imposed to protect young applicants from more experienced seniors, they have an unintended side effect of excluding returning workers, still disproportionately women, from the running.MethodsIn this joint effort by the European Society of Clinical Microbiology and Infectious Diseases, the Federation of European Microbiological Societies, the Infectious Disease Society of America, the International Society for Infectious Diseases and the Swiss Society for Infectious Diseases, we invited all European Congress of Clinical Microbiology and Infectious Diseases-affiliated medical societies and funding bodies to participate in a survey on current ‘early-career’ application restrictions and measures taken to provide protections for career breaks.RecommendationsThe following simple consensus recommendations are geared to funding bodies, academic societies and other organizations for the fair handling of eligibility for early-career awards: 1. Apply a professional, not physiological, age limit to applicants. 2. State clearly in the award announcement that career breaks will be factored into applicants' evaluations such that: ? Time absent is time extended: for every full-time equivalent of career break taken, the same full-time equivalent will be extended to the professional age limit. ? Opportunity costs will also be taken into account: people who take career breaks risk additional opportunity costs, with work that they did before the career break often being forgotten or poorly documented, particularly in bibliometric accounting. Although there is no standardized metric to measure additional opportunity costs, organizations should (a) keep in mind their existence when judging applicants' submissions, and (b) note clearly in the award announcement that opportunity costs of career breaks are also taken into account. 3. State clearly that further considerations can be undertaken, using more individualized criteria that are specific to the applicant population and the award in question.The working group welcomes feedback so that these recommendations can be improved and updated as needed.  相似文献   
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IntroductionThe management of endodontic emergencies has been particularly challenging during the coronavirus disease 2019 (COVID-19) outbreak because of the possible generation of airborne particles and aerosols. The aim of this report was to contribute to the practice of endodontics by proposing a general protocol for the management of emergencies showing the rationale for remote diagnosis, clinical procedures, and the use of personal protective equipment and barriers at the dental office during the COVID-19 outbreak.MethodsA review of the literature was conducted up to May 2020 on relevant institutional sites, aiming to retrieve the best updated evidence. The reporting considered the Reporting Tool for Practice Guidelines in Health Care statement.ResultsRecommendations from Cochrane Oral Health, the American Dental Association, and the Centers for Disease Control and Prevention were included along with the American Association of Endodontists resources and scientific articles that addressed the issue.ConclusionsThe proposed protocol could contribute to the management of endodontic emergencies at the dental office during the COVID-19 outbreak.  相似文献   
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BackgroundDiagnosis of human papillomavirus (HPV) disease remains a challenge due to several factors related to the cost, the workload of available commercial assays to detect and genotype HPV, and to the low prevalence of infected patients.ObjectiveOur study aimed to develop a real-time PCR, based on SPF10 primers, in order to combine HPV-DNA detection and genotype identification avoiding the negative samples.Study designValidation of SYBR-green based SPF10 real-time PCR on HPV-DNA plasmids followed by the investigation of the viral status in 92 samples from oropharyngeal (94%) cutaneous biopsies (3%) and anal smears (3%) which had previously been HPV-genotyped by LiPA hybridization. In-house HPV viral loads were performed to evaluate the SPF10 real-time PCR sensitivity.ResultsData showed that 100% of HPV plasmids, assessable by LiPA hybridization, were detected and genotyped appropriately after SPF10 real-time PCR assays. These results defined a range of melting temperature peaks for HPV positivity by real-time PCR. The efficient determination of the presence of HPV-DNA by SPF10 real-time PCR was validated for 98% of clinical samples compared to commercial method. Discordant results were due to a low HPV-DNA amount and to a supplementary HPV genotype identified. The SPF10 real-time PCR sensitivity was evaluated between 1 and 10 copies/103 cells using in-house HPV (6, 11 and 16) viral load assays.ConclusionThe real-time PCR method was efficient in combining screening and genotyping of HPV-DNA. Cost and workload reduction by SPF10 real-time PCR approach may facilitate earlier diagnosis and clinical management of HPV infected patients.  相似文献   
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We assessed the possible role in vivo CD4(+) CD8(+) T cells as a viral reservoir for simian immunodeficiency virus (SIV), in a macaque with 50% CD4(+) CD8(+) T cells in peripheral blood. During primary infection (day 14) of this rhesus macaque with the pathogenic SIVmac251 strain, proviruses were detected at similar frequencies in CD4(+) CD8(+) T cells (1/10) and CD4(+) T cells (1/10) and at a lower frequency in CD8(+) T cells (1/800). On day 235, no viral DNA was detected in CD8(+) cells, despite the persistent high viral load, indicating that CD8(+) cells do not constitute a reservoir during the chronic phase of SIV infection. Infection induced early lymphopenia of CD4(+), CD4(+) CD8(+), and CD8(+) cells; only the CD8(+) cell population returned to initial levels and expanded further. We found that CD4(+) CD8(+) T cells expressed the costimulatory CD28 molecule less and were more prone to die in vitro after phytohemagglutinin/interleukin 2 stimulation than were CD4(+) T cells. Taken together, massive death of CD4(+) CD8(+) T cells during acute stages of SIV infection may explain why CD8(+) T cells did not represent a major reservoir for SIV at the onset of infection.  相似文献   
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