Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 39
Filtrar
1.
Kidney Int Rep ; 9(5): 1333-1342, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38707810

RESUMO

Introduction: Hepatitis E virus (HEV) can cause chronic infection (≥3 months) and cirrhosis in immunocompromised patients, especially kidney transplant recipients. Low alanine aminotransferase (ALT) levels and high HEV intrahost diversity have previously been associated with evolution toward chronicity in these patients. We hypothesized that additional clinical and viral factors could be associated with the risk of chronic HEV infection. Methods: We investigated a series of 27 kidney transplant recipients with HEV infection, including 20 patients with chronic hepatitis E. Results: High tacrolimus trough concentration at diagnosis was the most relevant marker associated with chronic hepatitis E (9.2 vs. 6.4 ng/ml, P = 0.04). Most HEV genetic changes selected during HEV infection were compartmentalized between plasma and feces. Conclusion: This compartmentalization highlights the diversity and complexity of HEV replication compartments. Tacrolimus trough concentration at diagnosis of HEV infection could allow an early identification of patients at high risk of chronic hepatitis E and guide treatment initiation.

2.
Hepatol Commun ; 7(11)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37938097

RESUMO

BACKGROUND: Hepatitis E virus (HEV) is a zoonotic virus transmitted by pig meat and responsible for chronic hepatitis E in immunocompromised patients. It has proved challenging to reproduce this disease in its natural reservoir. We therefore aimed to develop a pig model of chronic hepatitis E to improve the characterization of this disease. METHODS: Ten pigs were treated with a tacrolimus-based regimen and intravenously inoculated with HEV. Tacrolimus trough concentration, HEV viremia, viral diversity, innate immune responses, liver histology, clinical disease and biochemical markers were monitored for 11 weeks post-infection (p.i.). RESULTS: HEV viremia persisted for 11 weeks p.i. HEV RNA was detected in the liver, small intestine, and colon at necropsy. Histological analysis revealed liver inflammation and fibrosis. Several mutations selected in the HEV genome were associated with compartmentalization in the feces and intestinal tissues, consistent with the hypothesis of extrahepatic replication in the digestive tract. Antiviral responses were characterized by a downregulation of IFN pathways in the liver, despite an upregulation of RIG-I and ISGs in the blood and liver. CONCLUSIONS: We developed a pig model of chronic hepatitis E that reproduced the major hallmarks of this disease. This model revealed a compartmentalization of HEV genomes in the digestive tract and a downregulation of innate immune responses in the liver. These original features highlight the relevance of our model for studies of the pathogenesis of chronic hepatitis E and for validating future treatments.


Assuntos
Hepatite E , Humanos , Suínos , Animais , Regulação para Baixo , Viremia , Tacrolimo , Imunidade Inata/genética
3.
Vaccines (Basel) ; 11(4)2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37112703

RESUMO

OBJECTIVE: Anti-HBs antibodies are elicited upon hepatitis B vaccination, and concentrations above 10 mIU/mL are considered protective. Our aim was to assess the relationship between IU/mL of anti-HBs and neutralization activity. METHODS: Immunoglobulins G (IgGs) were purified from individuals who received a serum-derived vaccine (Group 1), a recombinant vaccine, Genevac-B or Engerix-B (Group 2), or who recovered from acute infection (Group 3). IgGs were tested for anti-HBs, anti-preS1, and anti-preS2 antibodies and for their neutralizing activity in an in vitro infection assay. RESULTS: Anti-HBs IUs/mL value did not strictly correlate with neutralization activity. The Group 1 antibodies demonstrated a greater neutralizing activity than those of Group 2. Anti-preS1 antibodies were detected in Groups 1 and 3, and anti-preS2 in Group 1 and Group 2/Genhevac-B, but the contribution of anti-preS antibodies to neutralization could not be demonstrated. Virions bearing immune escape HBsAg variants were less susceptible to neutralization than wild-type virions. CONCLUSION: The level of anti-HBs antibodies in IUs is not sufficient to assess neutralizing activity. Consequently, (i) an in vitro neutralization assay should be included in the quality control procedures of antibody preparations intended for HB prophylaxis or immunotherapy, and (ii) a greater emphasis should be placed on ensuring that vaccine genotype/subtype matches with that of the circulating HBV.

4.
Virologie (Montrouge) ; 26(3): 228-239, 2022 05 01.
Artigo em Francês | MEDLINE | ID: mdl-35792839

RESUMO

Tenofovir is a nucleotidic analog inhibitor used in monotherapy as first line treatment of chronic Hepatitis B virus (HBV) infection. This drug requires a two-step phosphorylation by cellular kinases. The active triphosphate form inhibits viral DNA polymerase. Tenofovir has a very low oral bioavailability following oral administration. Hence, its oral administration requires the use of prodrugs: tenofovir disoproxil fumararate (TDF) or tenofovir alafénamide (TAF). TAF demonstrated a lower kidney and bone toxicity than TDF. TAF and TDF treatments allow prevention of chronic hepatitis B complications, which are cirrhosis and hepatocellular carcinoma. Prevention of these complications requires a virological response to the treatment, defined as undetectable HBV DNA. TDF and TAF are associated with virological response rates from 64 to 94 % after one year of treatment. This rate depends on HBV viral load at diagnostic, HBe antigen status, mutations in the HBV polymerase gene (Pol/RT) and patient compliance to the treatment. Tenofovir has a high genetic barrier and resistance mutations to this drug have not yet been described. However, mutations rt181T/V and/or rtN236T have been associated with reduced susceptibility to TDF/TAF in vitro and delayed response in vivo. Recently described mutations CYEI and rtA194T have been associated with reduced susceptibility to TDF/TAF in vitro without any change in viral response in vivo. Patient compliance can be improved using cognitive behavioral therapy, supporter interventions and use of short message service. Finally, some genetic polymorphisms in MRP(multidrug resistance-associated protein)-2 and MRP4 efflux transporters could be associated with TDF toxicity and virological response to TDF or TAF. In the perspective of functional HBV cure, TDF and TAF are likely to be still used, in association with new class of antivirals. For this reason, it is important to further characterize the pharmacological and virological factors associated with partial virological response to tenofovir.


Le ténofovir est un analogue nucléotidique inhibiteur de l'ADN polymérase à activité de transcriptase inverse du virus de l'hépatite B (VHB). Il nécessite une métabolisation intra-cellulaire par des kinases cellulaires pour obtenir la forme triphosphate active. Cette dernière est incorporée à l'ADN viral en cours de synthèse et exerce un effet terminateur de chaîne. Le ténofovir est administré sous forme de promédicaments : le ténofovir disoproxil fumarate (TDF) ou le ténofovir alafénamide (TAF). Le TAF se caractérise par une meilleure tolérance rénale et osseuse que le TDF. Le TDF et le TAF sont indiqués en monothérapie de longue durée pour le traitement de première intention des hépatites B chroniques. Ce traitement permet de prévenir la cirrhose et le carcinome hépatocellulaire qui sont les principales complications de l'hépatite B chronique. Le critère principal de suivi est l'obtention d'une réponse virologique, définie par une charge virale VHB indétectable. Le TDF et le TAF sont associés à des taux de réponse virologique de 64 à 94 % après un an de traitement. Ce taux de réponse dépend de facteurs virologiques, notamment le statut antigène HBe, la charge virale VHB au diagnostic et la présence de certaines mutations dans la polymérase virale (Pol/RT). Aucune résistance au ténofovir n'a été décrite au cours des essais cliniques, ce qui reflète la barrière génétique élevée associée à cette molécule. Néanmoins, les mutations rt181T/V et/ou rtN236T peuvent réduire la sensibilité au ténofovir in vitro et retarder la réponse virologique in vivo. Les mutations CYEI et A194T, récemment décrites, diminuent aussi la sensibilité au ténofovir in vitro mais ne semblent pas avoir d'impact sur la réponse au traitement. La réponse virologique dépend aussi de facteurs de l'hôte, principalement l'observance au traitement, cruciale pour prévenir les complications de l'infection. Cette observance peut être améliorée par des approches comportementales, le soutien d'un tiers ou des rappels par message texte. Enfin, certains polymorphismes génétiques au niveau des transporteurs MRP (multidrug resistance-associated protein)-2 ou MRP4 pourraient moduler la réponse virologique et la tolérance rénale du ténofovir. Dans une perspective de guérison fonctionnelle de l'hépatite chronique B, le ténofovir sera très probablement toujours utilisé, en association avec de nouveaux antiviraux. Pour ces raisons, il semble important de poursuivre l'identification des facteurs pharmacologiques et virologiques associés à la réponse virologique au ténofovir.


Assuntos
Hepatite B Crônica , Adenina/uso terapêutico , Alanina/uso terapêutico , Antivirais/efeitos adversos , Hepatite B Crônica/tratamento farmacológico , Humanos , Tenofovir/efeitos adversos
5.
J Womens Health (Larchmt) ; 31(10): 1472-1480, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35834620

RESUMO

Objective: We assessed whether general practitioner (GP) delivery of a vaginal self-sampling kit was non-inferior to home-mailed delivery on cervical cancer screening (CCS) participation. Methods: Two hundred and ten French GPs from Indre-et-Loire French department were randomized into two groups, and their unscreened women patients aged 30-65 were included in February-March 2015. In the GP delivery group (n = 105 GPs; 1,806 women), women were sent a reminder letter inviting them to collect a vaginal self-sampling kit at their regular GP's practice. In the home-mailed delivery group (n = 105 GPs; 1,806 women), women were sent a reminder letter with a vaginal self-sampling kit directly at home. The primary outcome was participation in complete CCS within 9 months. A cost-effectiveness analysis was also performed. Results: At 9 months, 14.9% (95% CI: 12.9-16.9) and 27.9% (95% CI: 25.7-30.0) of women in the GP and home-mailed delivery groups participated in complete CCS. The absolute between-group difference was -13.0 percentage points (95% CI: -15.9 to -10.0) in favor of the home-mailed delivery group, crossing the non-inferiority pre-defined non-inferiority margin of 5%. The home-mailed delivery strategy cost 50.81€ more per additional woman screened. Conclusions: The GP delivery was inferior to home-mailed delivery in increasing participation in CCS. Home-mailed delivery of a vaginal self-sampling kit is a cost-effective way to increase CCS in that the additional cost of this strategy seems acceptable. This study is registered at www.Clinicaltrials.gov NCT02255084.


Assuntos
Clínicos Gerais , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/prevenção & controle , Detecção Precoce de Câncer , Análise Custo-Benefício , Papillomaviridae , Infecções por Papillomavirus/diagnóstico , Manejo de Espécimes , Programas de Rastreamento , Esfregaço Vaginal
6.
J Viral Hepat ; 29(9): 719-726, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35633087

RESUMO

It was recently suggested that the composition of circulating hepatitis B subviral particles (SVPs) could be used to differentiate the various stages in chronic hepatitis B virus (HBV) infection, with significantly lower proportions of L and M proteins in inactive carriers than in individuals with chronic hepatitis. L protein is abundant in virions and filamentous SVPs but almost absent from spherical SVPs. We, therefore, performed a morphometric analysis of SVPs in these two groups of patients, by conducting a retrospective analysis on sera from 15 inactive carriers and 11 patients with chronic hepatitis infected with various HBV genotypes. Subviral particles were concentrated by centrifugation on a sucrose cushion, with monitoring by transmission electron microscopy. The percentage of filamentous SVPs and filament length for 100 SVPs was determined with a digital camera. The L protein PreS1 promoter was sequenced from viral genomes by the Sanger method. No marked differences were found between patients, some of whom had only spherical SVPs, whereas others had variable percentages of filamentous SVPs (up to 28%), of highly variable length. High filament percentages were not associated with a particular sequence of the L protein promoter, HBV genotype or even disease stage. High levels of circulating filamentous SVPs are probably more strongly related to individual host factors than to viral strain characteristics or disease stage.


Assuntos
Hepatite B Crônica , Hepatite B , Genótipo , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B/genética , Humanos , Estudos Retrospectivos
8.
Vaccines (Basel) ; 9(10)2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34696163

RESUMO

The impact of a third dose of COVID-19 vaccine on antibody responses is unclear in immunocompromised patients. The objective of this retrospective study was to characterize antibody responses induced by a third dose of mRNA COVID-19 vaccine in 160 kidney transplant recipients and 20 patients treated for chronic lymphocytic leukemia (CLL). Prevalence of anti-spike IgG ≥ 7.1 and ≥ 30 BAU/mL after the third dose were 47% (75/160) and 39% (63/160) in kidney transplant recipients, and 57% (29/51) and 50% (10/20) in patients treated for CLL. Longitudinal follow-up identified a moderate increase in SARS-CoV-2 anti-spike IgG levels after a third dose of vaccine in kidney transplant recipients (0.19 vs. 5.28 BAU/mL, p = 0.03) and in patients treated for CLL (0.63 vs. 10.7 BAU/mL, p = 0.0002). This increase in IgG levels had a limited impact on prevalence of anti-spike IgG ≥ 30 BAU/mL in kidney transplant recipients (17%, 2/12 vs. 33%, 4/12, p = 0.64) and in patients treated for CLL (5%, 1/20 vs. 45%, 9/20, p = 0.008). These results highlight the need for vaccination of the general population and the importance of non-medical preventive measures to protect immunocompromised patients.

9.
Antiviral Res ; 192: 105106, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34214504

RESUMO

Entecavir treatment failure can be observed in compliant patients despite an absence of detectable resistance mutations by Pol/RT Sanger sequencing. We hypothesized that these unexplained treatment failures could rely on other mechanisms of viral resistance, especially on mutations selected outside of the Pol/RT domain. Partial virological response to entecavir was observed in three patients treated with immunosuppressive drugs, without selection of Pol/RT resistance mutations. Mutations selected in the whole HBV genome during entecavir treatment and potentially associated with resistance were searched for using deep sequencing and characterized using a phenotypic resistance assay. Mutations Q206K (pre-core/core), Q120K (pre-S1/pre-S2, T-cell epitope) and A300E (spacer domain) were selected during entecavir treatment in patient #1 but were not associated with an increased level of resistance to entecavir or an increase in HBV replication capacity. Core promoter mutations T1753G, A1762T and G1764A were present as major mutations before and after treatment in patient #1. HBs Ag immune escape mutations were present as major mutations before and after treatment in patients #2 (sK122R, sT126I, sP127S and sG145R) and #3 (sM133I). We demonstrated that PVR to entecavir does not require selection of any resistance mutation in the whole HBV genome. Our results demonstrate that major mutations can be selected outside of the Pol/RT domain before or during entecavir treatment. These mutations could contribute to entecavir treatment failure by other mechanisms than an increased level of resistance.


Assuntos
Antivirais/uso terapêutico , Genoma Viral/genética , Guanina/análogos & derivados , Vírus da Hepatite B/genética , Hepatite B/tratamento farmacológico , Adulto , Idoso , Antivirais/farmacologia , Farmacorresistência Viral/efeitos dos fármacos , Farmacorresistência Viral/genética , Feminino , Guanina/uso terapêutico , Hepatite B/virologia , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/isolamento & purificação , Humanos , Masculino , Mutação , Cooperação do Paciente , Seleção Genética , Falha de Tratamento
10.
Molecules ; 26(5)2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33803417

RESUMO

A series of hitherto unknown (1,4-disubstituted-1,2,3-triazol)-(E)-2-methyl-but-2-enyl nucleosides phosphonate prodrugs bearing 4-substituted-1,2,3-triazoles were prepared in a straight approach through an olefin acyclic cross metathesis as the key synthetic step. All novel compounds were evaluated for their antiviral activities against HBV, HIV and SARS-CoV-2. Among these molecules, only compound 15j, a hexadecyloxypropyl (HDP)/(isopropyloxycarbonyl-oxymethyl)-ester (POC) prodrug, showed activity against HBV in Huh7 cell cultures with 62% inhibition at 10 µM, without significant cytotoxicity (IC50 = 66.4 µM in HepG2 cells, IC50 = 43.1 µM in HepG2 cells) at 10 µM.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Compostos Azo/química , Nucleosídeos/química , Organofosfonatos/química , Pró-Fármacos/síntese química , Pró-Fármacos/farmacologia , Alcenos/química , Animais , Linhagem Celular Tumoral , Chlorocebus aethiops , HIV-1/efeitos dos fármacos , Vírus da Hepatite B/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Metilação , SARS-CoV-2/efeitos dos fármacos , Relação Estrutura-Atividade , Triazóis/química , Células Vero
11.
Euro Surveill ; 26(3)2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33478625

RESUMO

We report the strategy leading to the first detection of variant of concern 202012/01 (VOC) in France (21 December 2020). First, the spike (S) deletion H69-V70 (ΔH69/ΔV70), identified in certain SARS-CoV-2 variants including VOC, is screened for. This deletion is associated with a S-gene target failure (SGTF) in the three-target RT-PCR assay (TaqPath kit). Subsequently, SGTF samples are whole genome sequenced. This approach revealed mutations co-occurring with ΔH69/ΔV70 including S:N501Y in the VOC.


Assuntos
Sequência de Bases , COVID-19/epidemiologia , Genoma Viral , SARS-CoV-2/genética , Deleção de Sequência/genética , Glicoproteína da Espícula de Coronavírus/genética , França/epidemiologia , Humanos
12.
Clin Microbiol Infect ; 27(2): 258-263, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33031948

RESUMO

OBJECTIVES: To describe the clinical evolution and predictors of symptom persistence during 2 months' follow-up in adults with noncritical coronavirus disease 2019 (COVID-19). METHODS: We performed descriptive clinical follow-up (day (D) 7, D30 and D60) of 150 patients with noncritical COVID-19 confirmed by real-time reverse transcriptase PCR at Tours University Hospital from 17 March to 3 June 2020, including demographic, clinical and laboratory data collected from the electronic medical records and by phone call. Persisting symptoms were defined by the presence at D30 or D60 of at least one of the following: weight loss ≥5%, severe dyspnoea or asthenia, chest pain, palpitations, anosmia/ageusia, headache, cutaneous signs, arthralgia, myalgia, digestive disorders, fever or sick leave. RESULTS: At D30, 68% (103/150) of patients had at least one symptom; and at D60, 66% (86/130) had symptoms, mainly anosmia/ageusia: 59% (89/150) at symptom onset, 28% (40/150) at D30 and 23% (29/130) at D60. Dyspnoea concerned 36.7% (55/150) patients at D30 and 30% (39/130) at D60. Half of the patients (74/150) at D30 and 40% (52/130) at D60 reported asthenia. Persistent symptoms at D60 were significantly associated with age 40 to 60 years old, hospital admission and abnormal auscultation at symptom onset. At D30, severe COVID-19 and/or dyspnoea at symptom onset were additional factors associated with persistent symptoms. CONCLUSIONS: Up to 2 months after symptom onset, two thirds of adults with noncritical COVID-19 had complaints, mainly anosmia/ageusia, dyspnoea or asthenia. A prolonged medical follow-up of patients with COVID-19 seems essential, whatever the initial clinical presentation.


Assuntos
COVID-19/complicações , COVID-19/epidemiologia , Adulto , Idoso , Ageusia/epidemiologia , Ageusia/etiologia , Anosmia/epidemiologia , Anosmia/etiologia , Astenia/epidemiologia , Astenia/etiologia , COVID-19/patologia , Dispneia/epidemiologia , Dispneia/etiologia , Feminino , Seguimentos , França/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , SARS-CoV-2 , Avaliação de Sintomas
13.
J Clin Virol ; 132: 104633, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32927357

RESUMO

OBJECTIVES: The aim of the present study was to evaluate the clinical performance of four SARS-CoV-2 immunoassays and their contribution in routine care for the diagnosis of COVID-19, in order to benefit of robust data before their extensive use. METHODS: The clinical performance of Euroimmun ELISA SARS-CoV-2 IgG, Abbott SARS-CoV-2 IgG, Wantai SARS-CoV-2 Ab ELISA, and DiaPro COVID-19 IgG confirmation were evaluated in the context of both a retrospective and a prospective analysis of COVID-19 patients. The retrospective analysis included plasma samples from 63 COVID-19 patients and 89 control (pre-pandemic) patients. The prospective study included 203 patients who tested either negative (n = 181) or positive (n = 22) by RT-PCR before serology sampling. RESULTS: The specificity was 92.1 %, 98.9 %, 100 % and 98.9 % and the sensitivity 14 days after onset of symptoms was 95.6 %, 95.6 %, 97.8 % and 95.6 % for Euroimmun IgG, Abbott IgG, Wantai Ab, and DiaPro IgG confirmation SARS-CoV-2 immunoassays, respectively. The low specificity of Euroimmun IgG (for ratio <5) was not confirmed in routine care setting (98.5 % negative agreement). Serology was complementary to RT-PCR in routine care and lead to identification of false positive (Ct>38, <2 targets detected) and false negative RT-PCR results (>1 month post onset of symptoms). CONCLUSIONS: Serology was complementary to RT-PCR for the diagnosis of COVID-19 at least 14 days after onset of symptoms. First line serology testing can be performed with Wantai Ab or Abbott IgG assays, while DiaPro IgG confirmation assay can be used as an efficient confirmation assay.


Assuntos
Anticorpos Antivirais/sangue , Teste para COVID-19 , COVID-19/diagnóstico , Imunoensaio , SARS-CoV-2/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Teste para COVID-19/métodos , Teste para COVID-19/normas , Criança , Feminino , Humanos , Imunoensaio/métodos , Imunoensaio/normas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Estudos Retrospectivos , SARS-CoV-2/genética , Sensibilidade e Especificidade , Adulto Jovem
14.
Antiviral Res ; 181: 104869, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32735901

RESUMO

Treatment adaptation after hepatitis B virus (HBV) treatment failure relies on genotypic resistance testing. However, the results of such tests are not always consistent with treatment response. These discrepancies may be due to differences in resistance levels between isolates with the same genotypic resistance testing profiles. We explored this hypothesis by investigating six cases of entecavir treatment failure with an integrative strategy combining genotypic and phenotypic resistance testing, medical record review and therapeutic drug monitoring. Among isolates with genotypic reduced susceptibility to entecavir, one displayed a higher level of resistance to entecavir (mean fold change in entecavir IC50 of 1 508 ± 531 vs. 318 ± 53, p = 0.008). This isolate harbored a substitution (rt250L) at a position reported to be associated with resistance (rt250V). Reversion to wild-type amino acid at this position partially restored susceptibility to entecavir, confirming that the rt250L mutation was responsible for the high level of resistance to entecavir. This is the first description of entecavir treatment failure associated with selection of the rt250L mutation without other entecavir resistance mutations. One isolate with genotypic resistance to entecavir, harboring the rt173L mutation, displayed a lower level of resistance than the other, harboring the rt202G mutation (mean fold change of 323 ± 124 vs. 6 036 ± 2 100, p = 0.20). These results suggest that isolates harboring the rt250L mutations should be considered resistant to entecavir, whereas isolates harboring the rt173L mutations should be considered to display reduced susceptibility to entecavir. An integrative approach to antiviral drug resistance in HBV would provide a more accurate assessment of entecavir treatment failures and help to improve the accuracy of genotypic testing algorithms.


Assuntos
Antivirais/farmacologia , Farmacorresistência Viral/genética , Guanina/análogos & derivados , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Adulto , Idoso , Substituição de Aminoácidos , DNA Viral/genética , Monitoramento de Medicamentos , Feminino , Genótipo , Guanina/farmacologia , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Fenótipo , Estudos Retrospectivos , Falha de Tratamento
15.
PLoS One ; 13(4): e0195611, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29664931

RESUMO

Current influenza vaccination strategy is based on limited analyses of circulating strains and has some drawbacks, as illustrated during the 2014-2015 season with the circulation of A(H3N2) viruses belonging to divergent genetic subgroups. We reasoned that these strains, poorly neutralized in vitro, may have been associated with vaccination failure and more severe diseases. We conducted a study on a continuous series of 249 confirmed influenza infections. Incidence was three fold greater than in the previous three years. Most isolates were A(H3N2) viruses (78%) and clustered in subgroups 3C.2a (57%) and 3C.3b (43%). We identified 23 non-synonymous mutations that had already been identified during previous seasons at low frequencies, except mutation Q197H, present in 26% of 3C.3b isolates. We identified lung disorder, tobacco smoking and A(H1N1)pdm09 infection as risk factor of severe influenza disease. In contrast, young age (< 5 years), A(H3N2) infection and initial admission to an emergency department were associated with a better outcome of influenza infection.


Assuntos
Hospitalização/estatística & dados numéricos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vacinas contra Influenza/efeitos adversos , Influenza Humana/tratamento farmacológico , Índice de Gravidade de Doença , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Feminino , França/epidemiologia , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/genética , Influenza Humana/epidemiologia , Influenza Humana/virologia , Pneumopatias/complicações , Masculino , Pessoa de Meia-Idade , Filogenia , Estudos Retrospectivos , Fatores de Risco , Fumar Tabaco/efeitos adversos , Falha de Tratamento , Vacinação , Adulto Jovem
16.
Am J Transplant ; 18(8): 1904-1913, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29377506

RESUMO

We aimed to determine the role of cytomegalovirus (CMV)-infected donor cells in the development of a CMV-specific immune response in kidney transplant recipients. We assessed the CMV pp65-specific immune response by using interferon-É£ ELISPOT and dextramers in peripheral blood mononuclear cells from 115 recipients (D+R- 31, D+R + 44, D-R + 40) late after transplantation (mean 59 ± 42 months). Receiving a kidney from a D+ donor resulted in a higher number of IFN-É£-producing anti-CMV T cells (P = .004). This effect disappeared with the absence of shared HLA class I specificities between donors and recipients (P = .430). To confirm the role of donor cells in stimulating the expansion of newly developed CMV-specific CD8+ T cells after transplantation, we compared the number of HLA-A2-restricted CMV-specific CD8+ T cells in primo-infected recipients who received an HLA-A2 or non-HLA-A2 graft. The median of anti-CMV pp65 T cells restricted by HLA-A2 was very low for patients who received a non-HLA-A2 graft vs an HLA-A2 graft (300 [0-14638] vs. 17972 [222-85594] anti-CMV pp65 CD8+ T cells/million CD8+ T cells, P = .001). This adds new evidence that CMV-infected kidney donor cells present CMV peptides and drive an inflation of memory CMV-specific CD8+ T cells, likely because of frequent CMV replications within the graft.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Genes MHC Classe I/imunologia , Rejeição de Enxerto/etiologia , Transplante de Rim/efeitos adversos , Leucócitos Mononucleares/imunologia , Doadores de Tecidos , Antígenos Virais/imunologia , Estudos Transversais , Infecções por Citomegalovirus/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/imunologia , Fosfoproteínas/imunologia , Estudos Retrospectivos , Linfócitos T Citotóxicos/imunologia , Proteínas da Matriz Viral/imunologia
17.
J Clin Virol ; 99-100: 38-43, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29306112

RESUMO

Cytomegalovirus (CMV) infection occurs frequently after solid organ transplantation. Therapeutic strategies, in particular when to start a curative treatment, has not yet been defined. The purpose of this study was to assess predictive factors associated with spontaneous clearance of CMV DNAemia in kidney transplant recipients. METHODS: All kidney recipients of a single center were recruited. Patients with at least one positive CMV DNAemia during the first year post transplantation were included in our analysis. Whole blood CMV PCR was performed using Abbott® RealTime CMV, calibrated according to WHO standards and expressed in log10 IU/ml (Detection = 1.79 IU log10/ml). Post transplantation, prophylaxis (valganciclovir) was given for 3 months for CMV positive recipients (R+) and 6 months for CMV positive donors giving to seronegative recipients (D + R-). Clinical and biological symptoms attributable to CMV were collected. We defined as spontaneous CMV clearance undetectable DNAemia before the fourth follow up without treatment. Results were expressed as mean ±â€¯SD. Results were prospectively assessed in a French multicenter validation cohort. RESULTS: Between 05/2012 and 05/2015, 95 patients had at least one positive CMV DNAemia. Thirty-six (37.8%) had spontaneous undetectable DNAemia. Fifty-nine patients had non-spontaneous CMV clearance. ROC analysis showed that an initial CMV DNAemia <2.75 log10/IU/mL was optimal to predict CMV spontaneous clearance. On multivariate analysis, factors associated with spontaneous CMV clearance were initial PCR level lower than 2.75 log10/IU/ml (OR = 33.8, 95% CI [7.1-160.0]), and absence of CMV DNAemia increase of more than 1 log10 between two analyses (OR = 128.0, 95% CI [11.9-1368.0]). Clinical and biological abnormalities were not associated CMV DNAemia spontaneous clearance. Observations made for the principal cohort were validated in an independent cohort of 49 kidney transplanted patients. CONCLUSIONS: Initial standardized CMV DNAemia level and evolution of DNAemia are the principal factors associated with CMV spontaneous clearance.


Assuntos
Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/etiologia , DNA Viral/sangue , Transplante de Rim/efeitos adversos , Idoso , Antibioticoprofilaxia , Antivirais/uso terapêutico , Citomegalovirus/genética , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/prevenção & controle , DNA Viral/genética , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Estudos Prospectivos , Curva ROC , Estudos Retrospectivos , Testes Sorológicos , Doadores de Tecidos , Valganciclovir/uso terapêutico
18.
Clin Infect Dis ; 66(11): 1733-1741, 2018 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-29211835

RESUMO

Background: In 2014-2015, 242 individuals aged 2-89 years were newly diagnosed with human immunodeficiency virus type 1 (HIV-1) in Roka, a rural commune in Cambodia. A case-control study attributed the outbreak to unsafe injections. We aimed to reconstruct the likely transmission history of the outbreak. Methods: We assessed in 209 (86.4%) HIV-infected cases the presence of hepatitis C virus (HCV) and hepatitis B virus (HBV). We identified recent infections using antibody (Ab) avidity testing for HIV and HCV. We performed amplification, sequencing, and evolutionary phylogenetic analyses of viral strains. Geographical coordinates and parenteral exposure through medical services provided by an unlicensed healthcare practitioner were obtained from 193 cases and 1499 controls during interviews. Results: Cases were coinfected with HCV (78.5%) and HBV (12.9%). We identified 79 (37.8%) recent (<130 days) HIV infections. Phylogeny of 202 HIV env C2V3 sequences showed a 198-sample CRF01_AE strains cluster, with time to most recent common ancestor (tMRCA) in September 2013 (95% highest posterior density, August 2012-July 2014), and a peak of 15 infections/day in September 2014. Three geospatial HIV hotspots were discernible in Roka and correlated with high exposure to the practitioner (P = .04). Fifty-nine of 153 (38.6%) tested cases showed recent (<180 days) HCV infections. Ninety HCV NS5B sequences formed 3 main clades, 1 containing 34 subtypes 1b with tMRCA in 2012, and 2 with 51 subtypes 6e and tMRCAs in 2002-2003. Conclusions: Unsafe injections in Cambodia most likely led to an explosive iatrogenic spreading of HIV, associated with a long-standing and more genetically diverse HCV propagation.


Assuntos
Surtos de Doenças , Infecções por HIV/epidemiologia , Infecções por HIV/etiologia , Injeções/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Camboja/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , HIV-1 , Humanos , Doença Iatrogênica/epidemiologia , Masculino , Pessoa de Meia-Idade , Filogenia , População Rural , Adulto Jovem
19.
PLoS One ; 12(8): e0183232, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28850623

RESUMO

BACKGROUND: Hepatitis C virus (HCV)-infected patients require a specific continuum of care (CoC) from HCV screening to treatment. We assessed CoC of HCV-infected patients in a longitudinal study. METHODS: We established a cohort of subjects undergoing HCV screening (high alanine aminotransferase levels or risk factors) during preventive consultations at a French regional medical center from 1993 to 2013. Patients were considered to be HCV-infected if HCV RNA was detected in their serum. CoC was assessed as described by Viner et al. (Hepatology 2015): Stage 1, HCV screening; Stage 2, HCV RNA testing; Stage 3, continuing care; Stage 4, antiviral treatment. Cox multivariate analysis was performed to identify factors favoring CoC, defined as at least one course of antiviral treatment. RESULTS: In total, 12,993 HCV tests were performed and 478 outpatients were found to be HCV-seropositive. We included 417 seropositive patients, after excluding false positives and patients lost to follow-up. The baseline characteristics of the patients were: sex ratio (M/F) 1.4; mean age 38.5 years; intravenous drug use (IDU) in 55%; and 28% in unstable social situations, estimated by the EPICES deprivation score. Antiviral treatment was initiated for 179 (42.9%) of the 379 (90.9%) patients attending specialist consultations. CoC was associated with screening after 1997 (HR 2.0, 95%CI 1.4-2.9), age > 45 years (HR 1.5, 95%CI 1.02-2.3), patient acceptance of care (HR 9.3, 95%CI 5.4-16.10), specialist motivation for treatment (HR 10.9, 95%CI 7.4-16.0), and absence of cancer (HR 6.7, 95%CI 1.6-27.9). Other comorbid conditions, such as depression and IDU, were not associated with CoC. CONCLUSIONS: Our 20-year cohort study reveals the real-life continuum of care for HCV-infected patients in France. The number of patients involved in HCV care after positive testing was substantial due to the organization of healthcare in France. An improved CoC along with new direct-acting antivirals should help to decrease chronic HCV infection.


Assuntos
Antivirais/uso terapêutico , Continuidade da Assistência ao Paciente , Hepacivirus/isolamento & purificação , Hepatite C Crônica/tratamento farmacológico , Adulto , Feminino , França , Hepatite C Crônica/diagnóstico , Humanos , Estudos Longitudinais , Perda de Seguimento , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade
20.
PLoS One ; 12(3): e0174852, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28362878

RESUMO

Hepatitis C virus (HCV) evolves rapidly in a single host and circulates as a quasispecies wich is a complex mixture of genetically distinct virus's but closely related namely variants. To identify intra-individual diversity and investigate their functional properties in vitro, it is necessary to define their quasispecies composition and isolate the HCV variants. This is possible using single genome amplification (SGA). This technique, based on serially diluted cDNA to amplify a single cDNA molecule (clonal amplicon), has already been used to determine individual HCV diversity. In these studies, positive PCR reactions from SGA were directly sequenced using Sanger technology. The detection of non-clonal amplicons is necessary for excluding them to facilitate further functional analysis. Here, we compared Next Generation Sequencing (NGS) with De Novo assembly and Sanger sequencing for their ability to distinguish clonal and non-clonal amplicons after SGA on one plasma specimen. All amplicons (n = 42) classified as clonal by NGS were also classified as clonal by Sanger sequencing. No double peaks were seen on electropherograms for non-clonal amplicons with position-specific nucleotide variation below 15% by NGS. Altogether, NGS circumvented many of the difficulties encountered when using Sanger sequencing after SGA and is an appropriate tool to reliability select clonal amplicons for further functional studies.


Assuntos
Hepacivirus/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Feminino , Variação Genética/genética , Genoma Viral/genética , Genômica/métodos , Glicoproteínas/genética , Humanos , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes , Análise de Sequência de DNA/métodos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...