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1.
Appl Environ Microbiol ; 84(1)2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29079627

RESUMO

Norovirus (NoV) is the leading cause of gastroenteritis outbreaks linked to oyster consumption. In this study, we investigated the potential of F-specific RNA bacteriophages (FRNAPH) as indicators of viral contamination in oysters by focusing especially on FRNAPH subgroup II (FRNAPH-II). These viral indicators have been neglected because their behavior is sometimes different from that of NoV in shellfish, especially during the depuration processes usually performed before marketing. However, a significant bias needs to be taken into account. This bias is that, in the absence of routine culture methods, NoV is targeted by genome detection, while the presence of FRNAPH is usually investigated by isolation of infectious particles. In this study, by targeting both viruses using genome detection, a significant correlation between the presence of FRNAPH-II and that of NoV in shellfish collected from various European harvesting areas impacted by fecal pollution was observed. Moreover, during their depuration, while the long period of persistence of NoV was confirmed, a similar or even longer period of persistence of the FRNAPH-II genome, which was over 30 days, was observed. Such a striking genome persistence calls into question the relevance of molecular methods for assessing viral hazards. Targeting the same virus (i.e., FRNAPH-II) by culture and genome detection in specimens from harvesting areas as well as during depuration, we concluded that the presence of genomes in shellfish does not provide any information on the presence of the corresponding infectious particles. In view of these results, infectious FRNAPH detection should be reconsidered as a valuable indicator in oysters, and its potential for use in assessing viral hazard needs to be investigated.IMPORTANCE This work brings new data about the behavior of viruses in shellfish, as well as about the relevance of molecular methods for their detection and evaluation of the viral hazard. First, a strong correlation between the presence of F-specific RNA bacteriophages of subgroup II (FRNAPH-II) and that of norovirus (NoV) in shellfish impacted by fecal contamination has been observed when both viruses are detected using molecular approaches. Second, when reverse transcription-PCR and culture are used to detect FRNAPH-II in shellfish, it appears that the genomes of the viruses present a longer period of persistence than infectious virus, and thus, virus genome detection fails to give information about the concomitant presence of infectious viruses. Finally, this study shows that FRNAPH persist at least as long as NoV does. These data are major arguments to reconsider the potential of FRNAPH as indicators of shellfish viral quality.


Assuntos
Genoma Viral , Norovirus/isolamento & purificação , Ostreidae/virologia , Fagos RNA/isolamento & purificação , Medição de Risco/métodos , Frutos do Mar/virologia , Animais , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Fezes/virologia , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/virologia , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/estatística & dados numéricos , Sensibilidade e Especificidade , Ensaio de Placa Viral/estatística & dados numéricos
2.
Appl Environ Microbiol ; 81(18): 6505-15, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26162878

RESUMO

F-specific RNA bacteriophages (FRNAPH) have been widely studied as tools for evaluating fecal or viral pollution in water. It has also been proposed that they can be used to differentiate human from animal fecal contamination. While FRNAPH subgroup I (FRNAPH-I) and FRNAPH-IV are often associated with animal pollution, FRNAPH-II and -III prevail in human wastewater. However, this distribution is not absolute, and variable survival rates in these subgroups lead to misinterpretation of the original distribution. In this context, we studied FRNAPH distribution in urban wastewater and animal feces/wastewater. To increase the specificity, we partially sequenced the genomes of phages of urban and animal origins. The persistence of the genomes and infectivity were also studied, over time in wastewater and during treatment, for each subgroup. FRNAPH-I genome sequences did not show any specific urban or animal clusters to allow development of molecular tools for differentiation. They were the most resistant and as such may be used as fecal or viral indicators. FRNAPH-II's low prevalence and low sequence variability in animal stools, combined with specific clusters formed by urban strains, allowed differentiation between urban and animal pollution by using a specific reverse transcription-PCR (RT-PCR) method. The subgroup's resistance over time was comparable to that of FRNAPH-I, but its surface properties allowed higher elimination rates during activated-sludge treatment. FRNAPH-III's low sequence variability in animal wastewater and specific cluster formation by urban strains also allowed differentiation by using a specific RT-PCR method. Nevertheless, its low resistance restricted it to being used only for recent urban pollution detection. FRNAPH-IV was too rare to be used.


Assuntos
Fezes/virologia , Fagos RNA/genética , Esgotos/virologia , Águas Residuárias/virologia , Microbiologia da Água , Poluição da Água , Animais , Sequência de Bases , Genoma Viral , Humanos , Filogenia , Reação em Cadeia da Polimerase , Fagos RNA/isolamento & purificação , Poluição da Água/análise
3.
J Sports Sci ; 5(1): 49-53, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3430680

RESUMO

The use of large cross-sectional norms on Brazilian children and youths aged 7 to 18 years within a six level competition plan helps to assess development status and monitor change. Non-athletic prototypes for comparative purposes are illustrated by the use of the lowest competitive level of 18 year olds to assess differences from internationally elite players. The purpose of this study was to establish the efficacy of this practice in male and female basketball and volleyball samples. Comparisons were made on 11 anthropometric and performance variables using percent difference (% delta) and z-score values. The z-scores were highest for height, weight, and jumping ability in both sports groups. The volleyball players were the more linear in physique and the better jumpers. Related to their prototypes the female basketball players had the highest estimated VO2 max (ml kg-1 min-1), and the best values of anaerobic power measures. It is concluded that differences in physique and performance at various levels of competition compared to non-athletic prototypes may be used to infer selective and training factors.


Assuntos
Antropometria , Aptidão Física , Esportes , Adolescente , Basquetebol , Brasil , Criança , Feminino , Humanos , Masculino , Educação Física e Treinamento
4.
Bull Assoc Anat (Nancy) ; 60(168): 63-79, 1976 Mar.
Artigo em Francês | MEDLINE | ID: mdl-797406

RESUMO

About one hundred years ago, the two major lymphological works of the XIXth century were published by SAPPEY; this gives the opportunity to recall who was the man who studied: Plagiostoma, Sharks, Teleosts, domestic Mammals and Man.


Assuntos
Sistema Linfático/anatomia & histologia , Anatomia/história , Animais , Peixes , França , História do Século XIX , Humanos , Coelhos
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