Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
1.
Sci Rep ; 11(1): 18456, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34531412

RESUMO

The variant 20I/501Y.V1, associated to a higher risk of transmissibility, emerged in Nice city (Southeast of France, French Riviera) during January 2021. The pandemic has resumed late December 2020 in this area. A high incidence rate together with a fast turn-over of the main circulating variants, provided us the opportunity to analyze modifications in clinical profile and outcome traits. We performed an observational study in the University hospital of Nice from December 2020 to February 2021. We analyzed data of sequencing of SARS-CoV-2 from the sewage collector and PCR screening from all positive samples at the hospital. Then, we described the characteristics of all COVID-19 patients admitted in the emergency department (ED) (n = 1247) and those hospitalized in the infectious diseases ward or ICU (n = 232). The UK-variant was absent in this area in December, then increasingly spread in January representing 59% of the PCR screening performed mid-February. The rate of patients over 65 years admitted to the ED decreased from 63 to 50% (p = 0.001). The mean age of hospitalized patients in the infectious diseases ward decreased from 70.7 to 59.2 (p < 0.001) while the proportion of patients without comorbidity increased from 16 to 42% (p = 0.007). Spread of the UK-variant in the Southeast of France affects younger and healthier patients.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/epidemiologia , SARS-CoV-2/genética , Esgotos/virologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , COVID-19/virologia , Comorbidade , Feminino , França/epidemiologia , Hospitalização/estatística & dados numéricos , Hospitais Universitários , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Reino Unido/epidemiologia , Vigilância Epidemiológica Baseada em Águas Residuárias
2.
Blood Adv ; 5(5): 1523-1534, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33683342

RESUMO

Dysregulated immune response is the key factor leading to unfavorable coronavirus disease 2019 (COVID-19) outcome. Depending on the pathogen-associated molecular pattern, the NLRP3 inflammasome can play a crucial role during innate immunity activation. To date, studies describing the NLRP3 response during severe acute respiratory syndrome coronavirus 2 infection in patients are lacking. We prospectively monitored caspase-1 activation levels in peripheral myeloid cells from healthy donors and patients with mild to critical COVID-19. The caspase-1 activation potential in response to NLRP3 inflammasome stimulation was opposed between nonclassical monocytes and CD66b+CD16dim granulocytes in severe and critical COVID-19 patients. Unexpectedly, the CD66b+CD16dim granulocytes had decreased nigericin-triggered caspase-1 activation potential associated with an increased percentage of NLRP3 inflammasome impaired immature neutrophils and a loss of eosinophils in the blood. In patients who recovered from COVID-19, nigericin-triggered caspase-1 activation potential in CD66b+CD16dim cells was restored and the proportion of immature neutrophils was similar to control. Here, we reveal that NLRP3 inflammasome activation potential differs among myeloid cells and could be used as a biomarker of a COVID-19 patient's evolution. This assay could be a useful tool to predict patient outcome. This trial was registered at www.clinicaltrials.gov as #NCT04385017.


Assuntos
COVID-19/sangue , Inflamassomos/metabolismo , Células Mieloides/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Biomarcadores/sangue , COVID-19/imunologia , Estudos de Casos e Controles , Humanos , Inflamassomos/sangue , Pessoa de Meia-Idade , Estudos Prospectivos , SARS-CoV-2/imunologia , SARS-CoV-2/isolamento & purificação
4.
JAMA Dermatol ; 157(2): 202-206, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33237291

RESUMO

Importance: Chilblain-like lesions have been reported during the coronavirus 2019 (COVID-19) pandemic. The pathophysiology of such manifestations remains largely unknown. Objective: To perform a systematic clinical, histologic, and biologic assessment in a cohort of patients with chilblain-like lesions occurring during the COVID-19 pandemic. Design, Setting, and Participants: In this prospective case series carried out with a COVID-19 multidisciplinary consultation group at the University Hospital of Nice, France, 40 consecutive patients presenting with chilblain-like lesions were included. Main Outcomes and Measures: Patients underwent a thorough general and dermatologic examination, including skin biopsies, vascular investigations, biologic analyses, interferon-alpha (IFN-α) stimulation and detection, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) polymerase chain reaction (PCR) and serologic analysis. Results: Overall, 40 consecutive patients with chilblain-like lesions were included. Most patients were young, with a median (range) age of 22 (12-67) years; 19 were male and 21 were female. The clinical presentation was highly reproducible with chilblain-like lesions mostly on the toes. Bullous and necrotic evolution was observed in 11 patients. Acrocyanosis or cold toes were reported in 19 (47.5%) cases. Criteria compatible with COVID-19 cases were noted in 11 (27.5%) within 6 weeks prior to the eruption. The real-time PCR (rt-PCR) testing results were negative in all cases. Overall, SARS-CoV-2 serology results were positive in 12 patients (30%). D-dimer concentration levels were elevated in 24 (60.0%) cases. Cryoglobulinemia and parvovirus B19 serologic results were negative for all tested patients. The major histologic findings were features of lymphocytic inflammation and vascular damage with thickening of venule walls and pericyte hyperplasia. A significant increase of IFN-α production after in vitro stimulation was observed in the chilblain population compared with patients with mild-severe acute COVID-19. Conclusions and Relevance: Taken together, our results suggest that chilblain-like lesions observed during the COVID-19 pandemic represent manifestations of a viral-induced type I interferonopathy. Trial Registration: ClinicalTrials.gov Identifier: NCT04344119.


Assuntos
COVID-19/complicações , Pérnio/etiologia , Adolescente , Adulto , Idoso , COVID-19/imunologia , Pérnio/imunologia , Criança , Feminino , Humanos , Interferon-alfa/imunologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
5.
Int J Antimicrob Agents ; 56(1): 105949, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32205204

RESUMO

BACKGROUND: Chloroquine and hydroxychloroquine have been found to be efficient on SARS-CoV-2, and reported to be efficient in Chinese COV-19 patients. We evaluate the effect of hydroxychloroquine on respiratory viral loads. PATIENTS AND METHODS: French Confirmed COVID-19 patients were included in a single arm protocol from early March to March 16th, to receive 600mg of hydroxychloroquine daily and their viral load in nasopharyngeal swabs was tested daily in a hospital setting. Depending on their clinical presentation, azithromycin was added to the treatment. Untreated patients from another center and cases refusing the protocol were included as negative controls. Presence and absence of virus at Day6-post inclusion was considered the end point. RESULTS: Six patients were asymptomatic, 22 had upper respiratory tract infection symptoms and eight had lower respiratory tract infection symptoms. Twenty cases were treated in this study and showed a significant reduction of the viral carriage at D6-post inclusion compared to controls, and much lower average carrying duration than reported in the litterature for untreated patients. Azithromycin added to hydroxychloroquine was significantly more efficient for virus elimination. CONCLUSION: Despite its small sample size, our survey shows that hydroxychloroquine treatment is significantly associated with viral load reduction/disappearance in COVID-19 patients and its effect is reinforced by azithromycin.


Assuntos
Azitromicina/administração & dosagem , Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Hidroxicloroquina/administração & dosagem , Pneumonia Viral/tratamento farmacológico , Adulto , COVID-19 , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Reação em Cadeia da Polimerase , SARS-CoV-2 , Carga Viral , Tratamento Farmacológico da COVID-19
6.
Transplant Proc ; 52(1): 204-211, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31889538

RESUMO

Cytomegalovirus (CMV) is the most common viral pathogen in kidney transplant recipients (KTRs), and CMV disease impacts patient and graft survivals. CMV-specific CD8 T cell mediated-immunity (CMI) may help to assess the risk of CMV disease and to adapt preventive treatment strategies. High-risk KTRs with CMV seropositive donors/seronegative recipients (D+/R-) were prospectively monitored after CMV prophylaxis discontinuation and during the first year post transplant for CMV viremia (World Health Organization standardization) and CMI (QuantiFERON-CMV). We analyzed the ability of CMI test to predict either subsequent spontaneous viral clearance or CMV disease after prophylaxis discontinuation in patients with asymptomatic viremia. We enrolled 12 consecutive (D+/R-) KTRs. Eleven patients developed a viremia during follow-up, but 7 of them (64%) exhibited a spontaneous viral clearance. At viremia onset, 6 of 11 patients (55%) had a positive CMI test, and all of them (6 of 6, 100%) had subsequent spontaneous viral clearance, compared with only 1 of 5 patients (20%) displaying a nonreactive CMI (P = .02). This latter patient exhibited a positive CMI test 15 days after viremia onset. Four of the 11 patients (36%) developed a CMV disease, and their CMI either remained nonreactive or became positive only after antiviral treatment. We conclude that D+/R- KTRs with asymptomatic viremia after prophylaxis discontinuation may benefit from QuantiFERON-CMV to predict when positive for the spontaneous viral clearance or when persistently negative or the development of a CMV disease.


Assuntos
Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/imunologia , Transplante de Rim , Viremia/diagnóstico , Adulto , Linfócitos T CD8-Positivos/imunologia , Citomegalovirus/imunologia , Infecções por Citomegalovirus/prevenção & controle , Feminino , Humanos , Imunidade Celular/imunologia , Masculino , Pessoa de Meia-Idade , Viremia/imunologia
7.
J Clin Virol ; 110: 42-44, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30530285

RESUMO

BACKGROUND: HSV-1 infection is very common worldwide and can be associated with severe medical conditions such as encephalitis and neonatal herpes. Current diagnosis relies heavily on molecular assays targeting the viral genome. One of the pitfalls of these assays is genetic variability, as viral polymorphisms located in the target region can impair the detection of HSV-1. OBJECTIVES: The aim of this study was to determine if genetic diversity of HSV-1 could account for equivocal assay results we obtained during routine diagnosis of HSV-1 in a genital specimen with the HSV-1 HSV-2 VZV R-gene® assay. STUDY DESIGN: The presence of HSV-1 in the genital swab studied was assessed using the HSV-1 HSV-2 VZV R-gene® qPCR assay and viral culture. Genetic variability of the patient's HSV-1 isolate was determined using molecular cloning, sequencing and comparison of the sequence of the isolate with those of previously published strains. RESULTS: We identified an HSV-1 isolate carrying a novel single-nucleotide polymorphism (SNP) located in the US7 gene from a genital swab. This SNP resulted in a missense substitution in the gI protein. It was responsible for the generation of an altered amplification curve when the genital specimen was checked for HSV-1 presence with the Argene HSV-1 HSV-2 VZV R-gene® assay, preventing unequivocal determination of the HSV-1 status of the sample analyzed. CONCLUSIONS: This study raises awareness of the risk of misdiagnosis of HSV-1 infections when "single-target" molecular assays are employed.


Assuntos
Variação Genética , Herpes Simples/diagnóstico , Herpesvirus Humano 1/genética , Polimorfismo de Nucleotídeo Único , Proteínas Virais/genética , DNA Viral , Feminino , Herpes Genital/diagnóstico , Herpes Genital/virologia , Herpes Simples/virologia , Herpesvirus Humano 1/isolamento & purificação , Humanos , Técnicas de Diagnóstico Molecular
8.
J Clin Med ; 7(12)2018 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-30544787

RESUMO

High-risk human papillomaviruses (HPVs) have been identified as the main contributors to cervical cancer. Despite various diagnostic tools available, including the predominant Papanicolaou test (Pap test), technical limitations affect the efficiency of cervical cancer screening. The aim of this study was to evaluate the diagnostic performance of spliced HPV16 E6/E7 mRNA viral loads (VL) for grade 2 or higher cervical intraepithelial neoplasia diagnosis. A new dedicated (quantitative reverse transcription polymerase chain reaction) qRT-PCR assay was developed, allowing selective quantification of several HPV16 E6/E7 mRNA: Full length (FL) with or without all or selected spliced forms (total E6/E7 mRNA corresponding to SP + E6^E7 mRNA (T), + spliced E6/E7 mRNA containing intact E7 ORF (SP), and E6/E7 mRNA containing disrupted E6 and E7 ORFs calculated by the following subtraction T-SP (E6^E7)). Twenty HPV16 DNA and mRNA positive uterine cervical smears representative of all cytological and histological stages of severity were tested. We have shown that all E6/E7 mRNA isoforms expression levels were significantly increased in high grade cervical lesions. Statistical analysis demonstrated that the SP-E6/E7 VL assay exhibited: (i) The best diagnostic performance for identification of both cervical intraepithelial neoplasia (CIN)2+ (90% (56⁻100) sensitivity and specificity) and CIN3+ (100% (72⁻100) sensitivity and 79% (49⁻95) specificity) lesions; (ii) a greater sensitivity compared to the Pap test for CIN2+ lesions detection (80% (44⁻97)); (iii) a predictive value of the histological grade of cervical lesions in 67% of atypical squamous cells of unknown significance (ASC-US) and 100% of low-grade (LSIL) patients. Overall, these results highlight the value of SP-E6/E7 mRNA VL as an innovative tool for improving cervical cancer screening.

9.
Genome Med ; 9(1): 33, 2017 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-28381277

RESUMO

BACKGROUND: Head and neck squamous cell carcinomas (HNSCCs) represent a heterogeneous group of cancers for which human papilloma virus (HPV) infection is an emerging risk factor. Previous studies showed promoter hypermethylation in HPV(+) oropharyngeal cancers, but only few consistent target genes have been so far described, and the evidence of a functional impact on gene expression is still limited. METHODS: We performed global and stratified pooled analyses of epigenome-wide data in HNSCCs based on the Illumina HumanMethylation450 bead-array data in order to identify tissue-specific components and common viral epigenetic targets in HPV-associated tumours. RESULTS: We identified novel differentially methylated CpGs and regions associated with viral infection that are independent of the anatomic site. In particular, most hypomethylated regions were characterized by a marked loss of CpG island boundaries, which showed significant correlations with expression of neighbouring genes. Moreover, a subset of only five CpGs in a few hypomethylated regions predicted HPV status with a high level of specificity in different cohorts. Finally, this signature was a better predictor of survival compared with HPV status determined by viral gene expression by RNA sequencing in The Cancer Genome Atlas cohort. CONCLUSIONS: We identified a novel epigenetic signature of HPV infection in HNSCCs which is independent of the anatomic site, is functionally correlated with gene expression and may be leveraged for improved stratification of prognosis in HNSCCs.


Assuntos
Carcinoma de Células Escamosas/genética , Metilação de DNA , Neoplasias de Cabeça e Pescoço/genética , Infecções por Papillomavirus/complicações , Regiões Promotoras Genéticas , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/metabolismo , Ilhas de CpG , Feminino , Regulação da Expressão Gênica , Genoma Humano , Neoplasias de Cabeça e Pescoço/etiologia , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma de Células Escamosas de Cabeça e Pescoço , Adulto Jovem
11.
Front Immunol ; 7: 197, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27252701

RESUMO

Several subsets of dendritic cells (DCs) are present in the oropharyngeal tonsillar tissues and are thought to behave as major actors in development and regulation of immunity by acting as a first line of recognition for airborne and alimentary antigens. We previously discovered in human adult tonsils infected with Epstein-Barr virus (EBV), a subset of DCs that expressed langerin/CD207, a lectin usually recognized as a hallmark of epidermal Langerhans cells (LCs). In the present study, we analyzed the content of several child and adult tonsils in order to characterize in more detail the phenotype of these tonsillar CD207-expressing DCs (tCD207 DCs) and to compare it with that of other human DC subsets. We showed that all the human tonsils studied (n = 12) contained significant proportions of tCD207 DCs among tonsillar cells expressing HLA-DR. Moreover, the presence of tCD207 DCs in tonsils from young children free of EBV infection indicated that these cells could be established early in the tonsil independently of EBV infection. We also showed that tCD207 DCs, that were found mainly located within the tonsillar lymphoid stroma, were distinguishable from LCs by the level of expression of CD1a and EpCAM, and also from human inflammatory DCs by the lack of CD1a, CD206, and CD14 expression. Detailed analysis of cell surface DC markers showed that tCD207 DCs were unrelated to CD141(+) DCs or macrophages, but defined a subtype of tonsillar DCs closely related to myeloid resident CD1c DCs. Since it was established that blood CD1c myeloid DCs exhibit plasticity and are capable of expressing CD207 notably in the presence of inflammatory cytokines, it is tempting to speculate that CD207(+) CD1c(+) DCs may play a specific immune role.

12.
Ann Biol Clin (Paris) ; 74(2): 244-50, 2016.
Artigo em Francês | MEDLINE | ID: mdl-27029729

RESUMO

Congenital cytomegalovirus (CMV) infection is the leading cause of sensoneurinal disability due to infectious congenital disease. The diagnosis of congenital CMV infection is based on the search of CMV in the urine within the first two weeks of life. Viral culture of urine is the gold standard. However, the PCR is highly sensitive and faster. It is becoming an alternative choice. The objective of this study is the validation of real-time PCR by Abbott RealTime CMV with m2000 for the detection of cytomegalovirus in urine. Repeatability, reproducibility, detection limit and inter-sample contamination were evaluated. Urine samples from patients (n=141) were collected and analyzed simultaneously in culture and PCR in order to assess the correlation of these two methods. The sensitivity and specificity of PCR were also calculated. The Abbott RealTime CMV PCR in urine is an automated and sensitive method (detection limit 200 UI/mL). Fidelity is very good (standard deviation of repeatability: 0.08 to 0.15 LogUI/mL and reproducibility 0.18 LogUI/mL). We can note a good correlation between culture and Abbott RealTime CMV PCR (kappa 96%). When considering rapid culture as reference, real-time PCR was highly sensitive (100%) and specific (98.2%). The real-time PCR by Abbott RealTime CMV with m2000 is optimal for CMV detection in urine.


Assuntos
Infecções por Citomegalovirus/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/instrumentação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Urinálise , Automação Laboratorial , Citomegalovirus/genética , Citomegalovirus/isolamento & purificação , Infecções por Citomegalovirus/congênito , Infecções por Citomegalovirus/genética , Infecções por Citomegalovirus/urina , Humanos , Recém-Nascido , Triagem Neonatal/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Urinálise/instrumentação , Urinálise/métodos , Urinálise/normas , Virologia/instrumentação , Virologia/métodos
13.
J Clin Virol ; 78: 27-30, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26967675

RESUMO

Use of direct-acting antiviral drugs (DAAs) greatly improves management of adults infected with hepatitis C virus (HCV) whether patients are treatment-naive or unsuccessfully pre-treated. Several inhibitors of viral nonstructural proteins (NS3/4A protease, NS5A and NS5B polymerase) allow a rapid HCV clearance and increase rates of sustained virological response. Both the EASL and AASLD guidelines have recently published up-to-date recommendations for their use, addressing each HCV genotype and particular situations. However, management of patients coinfected with hepatitis B virus (HBV) has been developed by these guidelines with reference to cases of HBV reactivation reported during previous anti-HCV regimens containing interferon known active against both HBV and HCV. In the setting of the interferon-free HCV therapies with DAAs only, the possibility of HBV reactivation during treatment of hepatitis C is raised due to viral interferences in HCV/HBV coinfected persons. Herein, we report a case of early HBV reactivation during DAAs-based anti-HCV treatment (ledipasvir/sofosbuvir) in a patient having a resolved HBV infection and chronically infected with HCV genotype 4 and HIV. Moreover, we review similar recent cases of HBV reactivation in patients infected with HBV and HCV genotype 1 during treatment of hepatitis C by regimen incorporating other combination of DAAs (sofosbuvir/simeprevir or daclatasvir/asunaprevir). Due to the potential risk of early HBV reactivation in HCV/HBV-coinfected patients during interferon-free DAAs-based HCV therapies, altogether these cases highlight the necessity to closely monitor HBV coinfection, regardless its stage (chronic, occult, resolved), whatever HCV genotype or class of DAAs used.


Assuntos
Antivirais/efeitos adversos , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/virologia , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Inibidores de Proteases/efeitos adversos , Ativação Viral/efeitos dos fármacos , Antivirais/administração & dosagem , Coinfecção/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores de Proteases/administração & dosagem
14.
World J Hepatol ; 7(18): 2177-83, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26328030

RESUMO

AIM: To evaluate virological response to telaprevir or boceprevir in combination with pegylated interferon and ribavirin and resistance mutations to NS3/4A inhibitors in hepatitis C virus-human immunodeficiency virus (HCV-HIV) coinfected patients in a real life setting. METHODS: Patients with HCV genotype 1-HIV coinfection followed in Nice University Hospital internal medicine and infectious diseases departments who initiated treatment including pegylated interferon and ribavirin (PegIFN/RBV) + telaprevir or boceprevir, according to standard treatment protocols, between August 2011 and October 2013 entered this observational study. Patient data were extracted from an electronic database (Nadis(®)). Liver fibrosis was measured by elastometry (Fibroscan(®)) with the following cut-off values: F0-F1: < 7.1 kPa, F2: 7.1-9.5 kPa, F3: 9.5-14.5 kPa, F4: ≥ 14.5 kPa. The proportion of patients with sustained virological response (SVR) twelve weeks after completing treatment, frequency and type of adverse events, and NS3/4A protease inhibitor mutations were described. RESULTS: Forty-one patients were included: 13 (31.7%) patients were HCV-treatment naïve, 22 (53.7%) had advanced liver fibrosis or cirrhosis (Fibroscan stage F3 and F4); none had decompensated cirrhosis or hepatocellular carcinoma; all were receiving antiretroviral treatment, consisting for most them (83%) in either a nucleoside reverse-transcriptase inhibitor/protease inhibitor or/integrase inhibitor combination; all patients had undetectable HIV-RNA. One patient was lost to follow-up. SVR was achieved by 52.5% of patients. Five patients experienced virological failure during treatment and four relapsed. Seven discontinued treatment due to adverse events. Main adverse events included severe anemia (88%) and rash (25%). NS3/4A protease mutations were analyzed at baseline and at the time of virological failure in the 9 patients experiencing non-response, breakthrough or relapse. No baseline resistance mutation could predict resistance to HCV protease inhibitor-based treatment. CONCLUSION: Telaprevir and boceprevir retain their place among potential treatment strategies in HIV-HCV coinfected patients including those with advanced compensated liver disease and who failed previous PegIFN/RBV therapy.

15.
J Clin Microbiol ; 51(5): 1428-33, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23426922

RESUMO

Hepatitis C virus (HCV) protease inhibitor resistance-associated substitutions are selected during triple-therapy breakthrough. This multicenter quality control study evaluated the expertise of 23 French laboratories in HCV protease inhibitor resistance genotyping. A panel of 12 well-defined blinded samples comprising two wild-type HCV strains, nine transcripts from synthetic NS3 mutant samples or from clinical strains, and one HCV RNA-negative sample was provided to the participating laboratories. The results showed that any laboratory with expertise in sequencing techniques should be able to provide reliable HCV protease inhibitor resistance genotyping. Only a 0.7% error rate was reported for the amino acid sites studied. The accuracy of substitution identification ranged from 75% to 100%, depending on the laboratory. Incorrect results were mainly related to the methodology used. The results could be improved by changing the primers and modifying the process in order to avoid cross-contamination. This study underlines the value of quality control programs for viral resistance genotyping, which is required prior to launching observational collaborative multicenter studies on HCV resistance to direct-acting antiviral agents.


Assuntos
Antivirais/farmacologia , Farmacorresistência Viral/genética , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/genética , Sequência de Aminoácidos , Antivirais/química , Sequência de Bases , Genótipo , Hepacivirus/enzimologia , Mutação , Inibidores de Proteases/química , Controle de Qualidade , Análise de Sequência de DNA
17.
J Gen Virol ; 92(Pt 10): 2428-2436, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21752964

RESUMO

We previously isolated human papillomavirus 83 (HPV83m) from a cervical smear. Sequence analysis of E6 and E7 proteins highlighted five mutations located in the second putative zinc-finger region of E6 (E6m), an important domain for protein-protein or protein-DNA interactions. Here, we show that E6m of HPV83m can trigger human primary cell proliferation and anchorage-independent growth properties, similarly to E6 of HPV16, a high-risk HPV (HR-HPV). Interestingly, we demonstrate that, in contrast to E6 of HPV16, E6m corrupts neither p53 stability nor telomerase activity, but acts as a specific modulator of the transcriptional machinery. By studying E6m reversion mutants, we confirmed the importance of the second zinc-finger domain in triggering the observed upregulation of cell growth and of the transcriptional machinery. Reversion of these mutations in E6m (to yield strain E6r) fully abolished the oncogenic potential of E6m, transforming the phenotype of E6 from a high-risk to a low-risk phenotype. Importantly, our data define the importance of a cluster of mutations in the second zinc finger of E6m in increasing the oncogenic potential of HPV83.


Assuntos
Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Papillomaviridae/genética , Papillomaviridae/patogenicidade , Displasia do Colo do Útero/virologia , Proliferação de Células , Células Cultivadas , DNA Viral/química , DNA Viral/genética , Células Epiteliais/fisiologia , Células Epiteliais/virologia , Humanos , Papillomaviridae/isolamento & purificação , Mutação Puntual , Estrutura Terciária de Proteína , Análise de Sequência de DNA , Dedos de Zinco
20.
J Virol Methods ; 154(1-2): 206-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18848582

RESUMO

Routine use of the automated chemiluminescent microparticle immunoassay Abbott ARCHITECT anti-HBc for diagnosis of hepatitis B is limited in case of borderline reactive sera with low signal close to the cut-off index. In order to determine the significance of anti-HBc detection when borderline reactivity occurs using the ARCHITECT anti-HBc assay, a comparative study was designed. 3540 serum samples collected over a 2-month period in the hospital of Nice were examined for markers of HBV infection (HBsAg, anti-HBs and anti-HBc). One hundred seven samples with sufficient volume and with borderline reactivity by the ARCHITECT assay were tested by two other anti-HBc assays, a microparticle enzyme immunoassay (MEIA, AxSYM Core, Abbott Laboratories, IL, USA) and an enzyme linked fluorescent assay (ELFA, VIDAS Anti-HBc Total II, bioMérieux, Lyon, France). Only 46 samples were confirmed by the AxSYM and the VIDAS assays. Additional serological information linked to patient history showed that the remaining samples (61) were false positives (11), had low titer of anti-HBc antibodies (13), or were inconclusive (37). This comparative study highlighted the existence of a grey zone around the cut-off index. Confirmative results through a different immunoassay are needed to confirm the diagnosis of HBV on borderline reactive sera using the ARCHITECT anti-HBc assay.


Assuntos
Anticorpos Anti-Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite B/diagnóstico , França , Humanos , Valor Preditivo dos Testes
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...