Risk Factors for Adopting Extreme Weight-Control Behaviors among Public School Adolescents in Salvador, Brazil: A Case-Control Study.

OBJECTIVE: This study identifies the risk factors for extreme weight-control behaviors among adolescents in public school in Salvador, northeastern Brazil. METHODS: A case-control study nested to a cross-sectional study, including 252 adolescents of both sexes, age between 11 to 17 years, with 84 cases and 168 age-matched controls was conducted. The variable outcome is represented by extreme weight-control behaviors, integrated by following the variables: self-induced vomiting and the use of laxatives, diuretics, or diet pills. Covariables included body image dissatisfaction, dieting, prolonged fasting, and self-perception of body weight. The study also investigated the demographic and anthropometric variables and economic conditions of the students' families. Conditional logistic regression was used to identify risk factors for the adoption of extreme weight-control behaviors among adolescents. RESULTS: Among the adolescents investigated, the conditional logistic regression explained 22% the occurrence of extreme weight-control behaviors and showed that these behaviors were positively associated to overweight (odds ratio [OR] = 3.61; 95% confidence interval [CI], 1.42-9.17), body image dissatisfaction (OR = 3.87; 95% CI, 1.75-8.54), and the adoption of a restrictive diet (OR = 2.83; 95% CI, 1.16-6.91). CONCLUSIONS: The results of this study suggest that among adolescents, overweight, body image dissatisfaction, and restrictive diet are important risk factors to adoption of extreme weight-control behaviors.

Cosavirus infection in persons with and without gastroenteritis, Brazil.

To determine possible cosavirus association with clinical disease, we used real-time reverse transcription PCR to test children and HIV-positive adults in Brazil with and without gastroenteritis. Thirteen (3.6%) of 359 children with gastroenteritis tested positive, as did 69 (33.8%) of 204 controls. Low prevalence, frequent viral co-infections, and low fecal cosavirus RNA concentrations argue against human pathogenicity.

Full genome sequence analysis of parechoviruses from Brazil reveals geographical patterns in the evolution of non-structural genes and intratypic recombination in the capsid region.

Due to high genome plasticity, the evolutionary fate and geographical history of picornaviruses is hard to follow. Here, we determined the complete coding sequences of eight human parechoviruses (HPeV) of types 1, 5 and 6 directly from clinical samples from Brazil. The capsid genes of these strains were not remarkably different from European, North American and Japanese HPeV. Full genome analysis revealed frequent intertypic recombination in the non-structural genome region. In addition, evidence of recombination between viruses of the same type in the capsid-encoding genome region among HPeV1 and HPeV4 was obtained. Bayesian phylogenetic analysis indicated that strains without evidence of recombination with each other in any genome region were separated by no more than 35 years of circulation. Interestingly, in the 3C gene, all Brazilian parechoviruses grouped together regardless of serotype. The most recent common ancestor of these strains dated back 108 years, suggesting long-term endemicity of this particular P3 genome lineage in South America. Our results support the idea that picornavirus replicative genes acquire capsid proteins introduced by new strains. Under certain epidemiological conditions, replicative genes may be maintained in circumscript geographical regions.

Genomic features and evolutionary constraints in Saffold-like cardioviruses.

This study identified the complete genomic sequence of four type 2 and type 3 human Saffold-like cardioviruses (SLCVs) isolated in Germany and Brazil. The secondary structures of the SLCV internal ribosome entry sites (IRESs) were deduced based on RNA base-pairing conservation and co-variation, using an established Theiler's murine encephalomyelitis virus (TMEV) IRES structure as a reference. The SLCV IRES was highly similar to that of TMEV, but motifs critical in TMEV for binding of the polypyrimidine tract-binding protein (PTB) were disrupted. In TMEV, corresponding alterations have been associated with reduced neurovirulence in mice. In the non-structural genome region, there was evidence of multiple intertypic recombination events between different SLCV types. Between viruses of the same type, recombination also occurred in the capsid-encoding genome region. There were apparently no recombination events between mouse TMEV and human SLCV. In another genus of the family Picornaviridae, Enterovirus, natural recombination occurs strictly within species and can serve as an additional criterion for delimiting species. Accordingly, the results of this study suggest that SLCV and TMEV may represent distinct species within the genus Cardiovirus.

Circulation of 3 lineages of a novel Saffold cardiovirus in humans.

Cardioviruses cause serious disease, mainly in rodents, including diabetes, myocarditis, encephalomyelitis, and multiple sclerosis-like disseminated encephalomyelitis. Recently, a human virus isolate obtained 25 years ago, termed Saffold virus, was sequenced and classified as a cardiovirus. We conducted systematic molecular screening for Saffold-like viruses in 844 fecal samples from patients with gastroenteritis from Germany and Brazil, across all age groups. Six cardioviruses were identified in patients <6 years of age. Viral loads were 283,305-5,044,412,175 copies/g of stool. Co-infections occurred in 4 of 6 children. No evidence for outbreak-like epidemic patterns was found. Phylogenetic analysis identified 3 distinct genetic lineages. Viral protein 1 amino acids were 67.9%-77.7% identical and had a distance of at least 39.4% from known cardioviruses. Because closely related strains were found on 2 continents, global distribution in humans is suspected. Saffold-like viruses may be the first human cardiovirus species to be identified.