Hepatitis C virus (HCV) genotype determination is required in clinical practice to establish the dose and duration of antiviral treatment. Although subtype identification does not impact on current therapy this is changing with new specific inhibitors of HCV enzymes and functions which are becoming available worldwide. These new drugs may yield different antiviral responses and resistance profiles. Accurate classification of HCV genotype and subtype is therefore crucial. An "in-house" method was developed for improving HCV subtyping and the results were compared with a second-generation line probe assay (LiPA) used extensively in Portugal. Phylogenetic analysis was undertaken of the C/E1 and NS5B genomic regions of HCV isolated from 72 prisoners with chronic HCV infection and from reference samples. Although LiPA is considered to be a good method for genotyping, HCV was subtyped in only 47.2% of cases compared with 95.8% of cases by the "in-house" method. Molecular data for both C/E1 and NS5B regions were obtained in 88.9% of the samples. Two out of 23 cases of subtype 1a were misclassified as subtype 1b by LiPA. A putative recombinant like RF1_2k/1b, two potential inter-genotypic recombinants 1b/4a and 3a/4a, and also a potential intra-genotypic recombinant 2q/2k in C/E1 and 2k/2a in NS5B were also identified. The "in-house" method enabled HCV to be subtyped accurately with the detection, in some cases, of recombinant viruses or dual HCV infections. Near full-length genomic analysis to characterize these potential recombinant viruses is planned.

Concerns regarding the status of marine ecosystems have increased in part due to traditional and emerging human activities in marine waters, driving a demand for approaches with high sample throughput capability to improve ecosystem monitoring. Nematodes are already used as indicator species in biodiversity assessments and biomonitoring of terrestrial and marine systems, with molecular approaches offering the opportunity to utilize these organisms further in large scale ecological surveys and environmental assessments. Based on an available nematode dataset for estuarine sediments of the Mira estuary (SW coast, Portugal), we evaluated the diversity of the nematode community of this system, using the molecular markers 18S rRNA and COI genes. These approaches were compared to voucher specimens from a morphological characterization of the same samples allowing validation and comparison between nematode communities. The spatial and temporal variability of the density and diversity of the nematode assemblages was analyzed based on morphological characterization to allow the validation and efficiency of the genetic characterization. A PCO ordination plot showed a distinct separation of the assemblages between sampling occasions confirmed by PERMANOVA analysis, which showed significant differences, although no significant differences were detected between sampling sites. The morphological characterization identified 50 genera of which only 26 and 25 distinct 18S rRNA and COI DNA barcodes, respectively, were obtained. 90.2% of the morphologically identified specimens representing eleven different genera, successfully generated DNA barcodes for both 18S rRNA and COI genes. This study confirmed that the success of the 18S rRNA gene PCR amplification is higher than of COI gene with 43 species amplified against 34. The study highlights a limitation of available sequences for both targets in databases when compared to the known diversity of marine nematodes. The gene sequences of Avó et al. DNA Barcoding of Estuarine Nematode Assemblages this study enriched the databases, contributing gene sequences from 7 to 16 new genera for the 18S rRNA and COI genes, respectively. A robust database of gene sequences is a prerequisite for the development of robust high sample throughput techniques to be applied in marine assessing and monitoring programs.

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Acta Med Port 2015 Nov-Dec;28(6):695-701 RESUMOIntrodução: A identificação dos genótipos do vírus da hepatite C foi essencial para o prognóstico e tratamento dos doentes crónicos durante os últimos anos. Foram objetivos deste estudo conhecer a frequência de genótipos do vírus da hepatite C nos últimos seis anos, e revelar o contributo de um ensaio in-house para caracterização molecular do vírus. Material e Métodos:A genotipagem do vírus da hepatite C por LiPA foi realizada em 923 amostras, maioritariamente provenientes de indivíduos do sexo masculino. A subtipagem do vírus da hepatite C pelo ensaio in-house com alvo nas regiões Core/E1 e/ou NS5B foi efetuada em 112 amostras. Resultados: Observámos elevada prevalência do genótipo 1 (56,6%), sendo a frequência do subtipo 1a quatro vezes superior ao subtipo 1b. Todos os casos de genótipo 3 (27,5%) foram classificados em subtipo 3a. Nas infeções pelo genótipo 4 (12,9%), identificaram-se os subtipos 4a (65,5%), 4d (31%), 4b (1,7%) e 4c (1,7%). Foram identificadas a RF1_2k/1b, recombinantes intragenótipo 2 e potenciais infeções mistas na população analisada. Discussão: Os subtipos mais prevalentes, 1a e 3a, estão descritos como comuns em utilizadores de drogas injetáveis. Apesar da maioria das amostras analisadas corresponder a reclusos (78,4%), não podemos excluir eventuais comportamentos de risco associados ao consumo de drogas ilícitas. Conclusões: A prevalência elevada do subtipo 1a, a frequência e diversidade do genótipo 4 e a identificação de vírus geneticamente recombinados, sugerem alteração do padrão molecular vírus da hepatite C descrito no passado. O ensaio in-house implementado revelou ser útil para a correta classificação do vírus da hepatite C e melhoria do conhecimento sobre a diversidade do vírus em circulação no país. Palavra-chave: Diversidade Genética; Genótipos; Subtipos; Vírus da Hepatite C. ABSTRACT Introduction:The identification of genotypes was essential for the prognosis and treatment of hepatitis C virus chronic patients in recent years. The aims of the study were to know the frequency of genotypes diagnosed in the last six years at the laboratory, and reveal the contribution of an in-house assay for molecular characterization of viruses. Material and Methods:The genotyping of hepatitis C virus by LiPA was performed in 923 samples, mostly from male individuals. The subtyping of hepatitis C virus by an in-house assay to target regions in the Core/E1 and/or NS5B was performed in 112 samples. Results:We observed a high prevalence of genotype 1 (56.6%), with a frequency of subtype 1a four times higher compared to 1b. All cases of genotype 3 (27.5%) were subtype 3a. For the cases of genotype 4 (12.9%), it were identified subtypes 4a (65.5%), 4d (31%), 4b (1.7%) and 4c (1.7%). Recombinants intragenotype 2, the RF1_2k/1b, and mixed infections, were also identified. Discussion: The most prevalent subtypes (1a and 3a) obtained are usually described in injecting drug users. Although most of the samples analysed match to inmates (78.4%), we cannot excl...

Nowadays molecular approaches are being used in population estimation of terrestrial nematode communities offering a more efficient and faster alternative over microscopy-based methods. A molecular profiling tool was developed using directed Terminal-Restriction Fragment Length Polymorphism (dT-RFLP) to characterize soil nematode assemblages by relative abundance of feeding guilds, and validated by comparison with traditional morphological method. Combining morphological and molecular analysis of benthic nematodes assemblages, the main aim of this study was to develop and validate the dT-RFLP tool for benthic nematodes. Estimation of population size was derived using real time PCR (qPCR). A molecular phylogenetic analysis of benthic nematodes was created based on a database of 18S rDNA sequences related to individuals identified to species level. dT-RFLP results showed that the digest strategy developed for soil nematodes was not suitable for benthic nematodes. A new dT-RFLP strategy for benthic assemblages was designed by using the sequence database coupled with cloning and sequencing the whole assemblage from five samples. Several solutions were identified by the DRAT software and tested empirically to select the optimum solution that separates the assemblages. qPCR results showed differences in gene copy number between two sampling sites, which is consistently with the results of nematode density obtained by traditional methods. The application of these high-throughput molecular approaches for benthic nematodes will improve sample throughput and their implementation more efficient and faster as an indicator of marine ecosystem health.