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1.
Clin Microbiol Infect ; 22(12): 1002.e9-1002.e14, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27554204

RESUMO

Rhinoviruses (RVs) are frequently detected respiratory viruses that cause mild common cold symptoms, but may also lead to more severe respiratory tract infections. The large number of RV types, classified into species A, B and C, hampers clear insights into the epidemiology and clinical significance of each RV type. The aim of this study was to map the circulation of RV types in the Amsterdam area. RV-positive nasopharyngeal and oropharyngeal samples, collected from 2007 to 2012 in the Academic Medical Centre (Amsterdam, the Netherlands), were typed based on the sequence of the region coding for capsid proteins VP4 and VP2. RV-A, RV-B and RV-C were found in proportions of of 52.4% (334/637), 11.3% (72/637), and 36.2% (231/637), respectively. We detected 129 of the 167 currently classified types. RVs circulated throughout the entire year with a peak in the autumn and a decline in the summer. Some RV types were observed throughout the entire sampling period and others had a more seasonal pattern. Nine RV-A and four RV-B novel provisionally assigned types were identified. This study provides an insight into the molecular epidemiology of RVs in the Amsterdam area. The RVs circulating are diverse and include several provisionally new types.


Assuntos
Proteínas do Capsídeo/genética , Resfriado Comum/epidemiologia , Rhinovirus/genética , Rhinovirus/isolamento & purificação , Resfriado Comum/virologia , Técnicas de Genotipagem , Humanos , Epidemiologia Molecular , Nasofaringe/virologia , Países Baixos/epidemiologia , RNA Viral/isolamento & purificação , Rhinovirus/classificação , Estações do Ano , Análise de Sequência de DNA
2.
PLoS One ; 11(3): e0152509, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27028128

RESUMO

BACKGROUND: Despite much debate, there is little evidence on consequences of consent procedures for residual tissue use. Here, we investigated these consequences for the availability of residual tissue for medical research, clinical practice, and patient informedness. METHODS: We conducted a randomised clinical trial with three arms in six hospitals. Participants, patients from whom tissue had been removed for diagnosis or treatment, were randomised to one of three arms: informed consent, an opt-out procedure with active information provision (opt-out plus), and an opt-out procedure without active information provision. Participants received a questionnaire six weeks post-intervention; a subsample of respondents was interviewed. Health care providers completed a pre- and post-intervention questionnaire. We assessed percentage of residual tissue samples available for medical research, and patient and health care provider satisfaction and preference. Health care providers and outcome assessors could not be blinded. RESULTS: We randomised 1,319 patients, 440 in the informed consent, 434 in the opt-out plus, and 445 in the opt-out arm; respectively 60.7%, 100%, and 99.8% of patients' tissue samples could be used for medical research. Of the questionnaire respondents (N = 224, 207, and 214 in the informed consent, opt-out plus, and opt-out arms), 71%, 69%, and 31%, respectively, indicated being (very) well informed. By questionnaire, the majority (53%) indicated a preference for informed consent, whereas by interview, most indicated a preference for opt-out plus (37%). Health care providers (N = 35) were more likely to be (very) satisfied with opt-out plus than with informed consent (p = 0.002) or opt-out (p = 0.039); the majority (66%) preferred opt-out plus. CONCLUSION: We conclude that opt-out with information (opt-out plus) is the best choice to balance the consequences for medical research, patients, and clinical practice, and is therefore the most optimal consent procedure for residual tissue use in Dutch hospitals. TRIAL REGISTRATION: Dutch Trial Register NTR2982.


Assuntos
Pesquisa Biomédica , Inquéritos e Questionários , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos
3.
J Viral Hepat ; 22(3): 263-71, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25174990

RESUMO

The natural course of serum HCV RNA levels during chronic infection remains unclear. We investigated HCV RNA levels and factors associated with HCV RNA levels for the entire course from HCV seroconversion. We measured HCV RNA levels of 54 HCV seroconverters from the Amsterdam Cohort Studies among drug users at yearly intervals up to 23 years using bDNA (VERSANT 3.0, lower limit of detection 615 IU/mL). Samples below the cut-off of the assay were tested by TMA (Siemens VERSANT, detection limit 5 IU/mL). We used a latent class linear mixed model to examine the HCV RNA patterns and factors associated with HCV RNA levels. The median follow-up time was 10.8 years (IQR 6.5-14.9). We found two distinct HCV RNA patterns characterized by 45/54 cases and 9/54 cases. In multivariable analyses, HCV RNA levels were 0.41 log(10) IU/mL (95% confidence interval (CI) 0.06-0.75) higher for males as compared to females. Individuals with the IL28B CC genotype had 0.40 log(10) IU/mL (95% 0.08-0.73) higher HCV RNA levels than individuals with IL28B CT/TT genotypes. Body mass index (BMI) was associated with higher HCV RNA levels, 0.055 log(10) IU/mL per BMI point (95% CI 0.027-0.083). In this unique study, which examines the HCV RNA patterns over an extended period and following seroconversion, male sex, IL28B CC genotype and BMI were independently associated with higher average HCV RNA levels. These results contribute to defining the natural history of HCV infection and could play an important part in clinical decision-making.


Assuntos
Usuários de Drogas , Genótipo , Hepacivirus , Hepatite C Crônica/genética , Hepatite C Crônica/virologia , Interleucinas/genética , Carga Viral , Adulto , Índice de Massa Corporal , Estudos de Coortes , Feminino , Seguimentos , Predisposição Genética para Doença , Hepacivirus/genética , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/sangue , Anticorpos Anti-Hepatite C/imunologia , Hepatite C Crônica/epidemiologia , Hepatite C Crônica/imunologia , Humanos , Interferons , Masculino , Fatores Sexuais
4.
J Viral Hepat ; 20(11): 779-89, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24168257

RESUMO

Narlaprevir, a hepatitis C virus (HCV) NS3/4A serine protease inhibitor, has demonstrated robust antiviral activity in a placebo-controlled phase 1 study. To study evolutionary dynamics of resistant variants, the NS3 protease sequence was clonally analysed in thirty-two HCV genotype 1-infected patients following treatment with narlaprevir. Narlaprevir monotherapy was administered for one week (period 1) followed by narlaprevir/pegylated interferon-alpha-2b combination therapy with or without ritonavir (period 2) during two weeks, interrupted by a washout period of one month. Thereafter, all patients initiated pegylated interferon-alpha-2b/ribavirin combination therapy. Longitudinal clonal analysis was performed in those patients with NS3 mutations. After narlaprevir re-exposure, resistance-associated mutations at position V36, T54, R155 and A156 were detected in five patients in >95% of the clones. Narlaprevir retreatment resulted in a 2.58 and 5.06 log10 IU/mL viral load decline in patients with and without mutations, respectively (P=<0.01). After treatment, resistant variants were replaced with wild-type virus within 2-24 weeks in three patients. However, the R155K mutation was still observed 3.1 years after narlaprevir dosing in two patients in 5% and 45% of the viral population. Resistant variants could be detected early during treatment with narlaprevir. A slower viral load decline was observed in those patients with resistance-associated mutations detectable by direct population sequencing. These mutations disappeared within six months following treatment with the exception of R155K mutation, which persisted in two patients.


Assuntos
Antivirais/uso terapêutico , Dipeptídeos/uso terapêutico , Evolução Molecular , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Inibidores de Proteases/uso terapêutico , Sulfonas/uso terapêutico , Proteínas não Estruturais Virais/genética , Adulto , Ciclopropanos , Quimioterapia Combinada/métodos , Feminino , Hepacivirus/genética , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Leucina/análogos & derivados , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/uso terapêutico , Prolina/análogos & derivados , Proteínas Recombinantes/uso terapêutico , Ribavirina/uso terapêutico , Análise de Sequência de DNA , Ureia , Carga Viral
5.
J Clin Microbiol ; 51(1): 238-42, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23152551

RESUMO

To evaluate the analytical performance and explore the clinical applicability of the new Roche cobas AmpliPrep/cobas TaqMan HCV test, v2.0 (CAP/CTM v2.0), a platform comparison was performed on panels and diagnostic samples with the Roche cobas AmpliPrep/cobas TaqMan HCV test (CAP/CTM v1.0), the Siemens Versant HCV RNA 3.0 branched DNA (bDNA) test, the Abbott m2000 RealTime HCV assay (Realtime assay), and the Siemens Versant HCV transcription-mediated amplification (TMA) test (TMA assay). The analytical performance of the CAP/CTM v2.0 on WHO and Acrometrix panels and clinical specimens of patients infected with HCV genotype 1, 2, 3, 4, 5, or 6 relative to that of the CAP/CTM v1.0 was significantly improved. In a qualitative comparison of the CAP/CTM v2.0 relative to the TMA assay on genotype 1 to 4 samples, the two tests proved to be almost equally sensitive. Response-guided therapy in one of five HCV genotype 4-infected patients previously tested with the CAP/CTM v1.0 would have significantly changed if tested with the CAP/CTM v2.0. In conclusion, the Roche CAP/CTM v2.0 has significantly better performance characteristics than the former CAP/CTM HCV v1.0 and the bDNA assay and performance characteristics comparable to those of the Realtime assay.


Assuntos
Hepacivirus/isolamento & purificação , Hepatite C/virologia , Técnicas de Diagnóstico Molecular/métodos , RNA Viral/isolamento & purificação , Carga Viral/métodos , Hepacivirus/genética , Humanos , RNA Viral/genética
6.
J Med Virol ; 81(3): 413-6, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19152408

RESUMO

Serial monotherapy and add-on regimes for treatment of chronic hepatitis B virus (HBV) infection may induce the accumulation of viral resistance mutations in patients, reducing the options for ongoing viral suppression. The induction of antiviral resistance by serial application of polymerase inhibitors does not necessarily imply that the subsequent combined use of the drugs will fail. Some HIV strains resistant to one polymerase inhibitor show increased susceptibility to another polymerase inhibitor. After failure of sequential lamivudine and adefovir monotherapy, two patients with hepatitis B changed to treatment with lamivudine plus adefovir and had renewed suppression of HBV. To study the mutational history of resistant HBV subpopulations in the two patients, a part of the HBV polymerase gene was amplified, cloned, sequenced, and analyzed for the presence of mutations, in sequential plasma samples. In both patients serial monotherapy caused the replacement in all HBV clones of wild-type virus by classical lamivudine resistant mutants (L180M and M204V/I), which were replaced subsequently by adefovir resistant mutants (A181V and N236T). When finally lamivudine was added to adefovir, the A181V adefovir mutation persisted in all clones and lamivudine-related mutations did not reappear. During 18 months of combination therapy, HBV-DNA levels decreased 10,000, respectively, 1,000-fold, despite the earlier resistance to lamivudine and adefovir. Although clinically insufficient, this effect indicates that HBV polymerase resistance mutations may be antagonistic, which is relevant if chronic HBV infection is to be treated by a combination of polymerase inhibitors.


Assuntos
Adenina/análogos & derivados , Antivirais/uso terapêutico , Farmacorresistência Viral , Vírus da Hepatite B/efeitos dos fármacos , Lamivudina/uso terapêutico , Organofosfonatos/uso terapêutico , Adenina/farmacologia , Adenina/uso terapêutico , Adulto , Substituição de Aminoácidos , Antivirais/farmacologia , Análise Mutacional de DNA , DNA Viral/genética , Quimioterapia Combinada , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Humanos , Lamivudina/farmacologia , Masculino , Mutação de Sentido Incorreto , Organofosfonatos/farmacologia , Análise de Sequência de DNA , Carga Viral
7.
J Clin Microbiol ; 38(9): 3442-4, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10970398

RESUMO

Hepatitis C virus (HCV) RNA was detected and quantified in human fecal specimens with the Roche COBAS AMPLICOR system adapted by us for fecal specimens. HCV RNA could be detected in the feces of four of six (67%) patients chronically infected with HCV, with loads up to about 2.8 x 10(5) copies/ml of feces. The same HCV genotypes were observed in feces and plasma as determined by direct sequencing of the 5' untranslated region.


Assuntos
Fezes/virologia , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , RNA Viral/análise , Hepatite C Crônica/diagnóstico , Humanos , RNA Viral/sangue , Kit de Reagentes para Diagnóstico
8.
Transfusion ; 40(6): 682-6, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10864988

RESUMO

BACKGROUND: A new device for sterile docking, the Compodock (Fresenius NPBI Transfusion Technology), was developed for connecting PVC tubing for medical use while maintaining sterility. STUDY DESIGN AND METHODS: Sterility of the connections was assessed by welding tubing with a heavy exterior contamination with Bacillus subtilis spores and also by welding in an environment contaminated with aerosols of B. subtilis. Tubing was either dry or liquid-filled ("wet") and had various diameters. Bacterial culture medium was flushed through the welded area and subsequently cultured. Tensile strength was measured, and, under semi-routine conditions, Compodock was tested for user friendliness and speed. RESULTS: None of the cultures of welded tubing with exterior contamination showed growth, neither the dry-dry (n = 434) nor the wet-wet connections (n = 622). Cultures were also negative for welds made in the contaminated environment (dry-dry, 67; wet-wet, 55). Tensile strength complied fully with ISO 3826 standards (that is, a force of 20 newtons [N] for 15 sec), with a mean maximal strength ranging from 73 to 100 N, depending on diameter and content of the tubing. The semi-routine handling was regarded as good: welds were easily opened; there were clear instructions and error warnings; and the processing time averaged 52 seconds. CONCLUSION: The Compodock is able to maintain a functionally closed system, with maintenance of sterility, despite heavy exterior bacterial contamination; tensile strength conformed to ISO standards. Compodock is suitable for routine implementation in the blood bank.


Assuntos
Preservação de Sangue/instrumentação , Coleta de Amostras Sanguíneas/instrumentação , Bacillus subtilis/isolamento & purificação , Sangue/microbiologia , Contaminação de Equipamentos , Desenho de Equipamento , Estudos de Avaliação como Assunto , Humanos , Controle de Qualidade , Esterilização , Resistência à Tração
9.
Transfusion ; 40(5): 575-9, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10827262

RESUMO

BACKGROUND: The objective of this study was the evaluation of NAT technology for the detection of HCV RNA in plasma pools according to the recommendations of the Paul Ehrlich Institute (5000 IU/mL/donation) and the Committee for Proprietary Medical Products (100 IU/mL/manufacturing pool). STUDY DESIGN AND METHODS: Serial dilutions of both the EUROHEP standard (3,800 genome equivalents [geq]/mL; HCV genotype 1) and the World Health Organization (WHO) international standard (100,000 IU/mL; HCV genotype 1) were made in S/D plasma (ESPEP plasma, OctaPharma), which was nonreactive in serologic tests. Serial dilutions of plasma (2 mL) were used for extraction of HCV RNA with an automated version of a nucleic acid isolation method (NucliSens Extractor, Organon Teknika). HCV RNA was co-extracted from 2 mL of plasma, together with 84 copies of an in vitro-synthesized single-strand RNA serving as internal extraction control (IC) to monitor the efficiency of extraction and PCR. Amplification and detection of both HCV RNA and IC RNA were performed with an automated PCR system and a qualitative HCV assay (COBAS Amplicor 2.0 HCV, Roche Diagnostics). RESULTS: A cutoff value of 16 geq per mL (10/10 runs [100% hit rate]) was found by using the EUROHEP standard, whereas the WHO international standard had a cutoff value of approximately 12 IU per mL (10/10 runs [100% hit rate]). The IC had a cutoff value of approximately 17.5 copies per mL (6/6 runs [100% hit rate]). Forty-two copies per mL of IC RNA were found in 282 of 284 runs (99% hit rate). The negative controls (ESDEP plasma) were negative in all experiments. Experiments with pool sizes of 12, 24, 48, and 96 using serial dilutions of the WHO international standard revealed a cutoff value of 8 IU per mL (100% hit rate). The EUROHEP standard and the WHO international standard were detected with a 50 percent detection endpoint of 5.2 geq per mL and 1.5 IU per mL, respectively. CONCLUSION: This test system (NucliSens Extractor, and the COBAS Amplicor 2.0 HCV assay) revealed a high sensitivity for HCV RNA; considering the proposed requirements for sensitivity of NAT assays for the detection of HCV RNA in donor plasma, pool sizes of about 400 donors are possible. These endpoint results indicated that 1 IU is equal to about 3.4 geq.


Assuntos
Hepacivirus/genética , RNA Viral/sangue , Autoanálise/normas , Transmissão de Doença Infecciosa/estatística & dados numéricos , Estudos de Avaliação como Assunto , Humanos , Padrões de Referência , Sensibilidade e Especificidade , Reação Transfusional
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