Is the human T-cell lymphotropic virus type 2 in the process of endogenization into the human genome?

Human T-cell lymphotropic virus type 2 (HTLV-2) infection has been shown to be endemic among intravenous drug users in parts of North America, Europe and Southeast Asia and in a number of Amerindian populations. Despite a 65% genetic similarity and common host humoral response, the human T-cell lymphotropic viruses type 1 (HTLV-1) and 2 display different mechanisms of host interaction and capacity for disease development. While HTLV-1 pathogenicity is well documented, HTLV-2 etiology in human disease is not clearly established. From an evolutionary point of view, its introduction and integration into the germ cell chromosomes of host species could be considered as the final stage of parasitism and evasion from host immunity. The extraordinary abundance of endogenous viral sequences in all vertebrate species genomes, including the hominid family, provides evidence of this invasion. Some of these gene sequences still retain viral characteristics and the ability to replicate and hence are potentially able to elicit responses from the innate and adaptive host immunity, which could result in beneficial or pathogenic effects. Taken together, this data may indicate that HTLV-2 is more likely to progress towards endogenization as has happened to the human endogenous retroviruses millions of years ago. Thus, this intimate association (HTLV-2/human genome) may provide protection from the immune system with better adaptation and low pathogenicity.

Risk factors associated with hypovitaminosis D in HIV/aids-infected adults.

OBJECTIVE: To investigate risk factors associated with hypovitaminosis D in adult patients infected with HIV/aids, at a referral hospital in Maceió, Brazil. SUBJECTS AND METHODS: This cross-sectional study involved 125 patients evaluated from April to September 2013 by means of interviews, review of medical records, physical examination, and laboratory tests. The data were analyzed using the SPSS® software, version 17.0; the prevalence of hypovitaminosis D and mean levels of vitamin D were determined. The association between hypovitaminosis D and the independent variables was assessed using the Chi-square or the Fisher's exact tests; mean vitamin D concentrations were analyzed using Kolmogorov-Smirnov, Mann-Whitney, and Kruskal-Wallis tests. The level of significance was set at 5% across tests. RESULTS: The prevalence of hypovitaminosis D was 24%, with a significant association with higher household income (p < 0.05). Higher vitamin D levels were associated with female gender (p < 0.001), no use of sunscreen (p < 0.05), and previous opportunistic infections (p < 0.01). Lower values were associated with the use of antiretroviral medication (p < 0.05), overweight and obesity (p < 0.01). CONCLUSION: Lower vitamin D concentrations were significantly associated with well-known risk factors for hypovitaminosis D: use of sunscreen, antiretroviral medication, overweight, and obesity. The prevalence of hypovitaminosis D in this study, considering values > 20 ng/mL or > 30 ng/mL as vitamin D sufficiency, was lower to that of previous studies with HIV-infected patients, a fact that might be related to the low latitude and high intensity of solar radiation of the location of the present study.

Risk factors associated with hypovitaminosis D in HIV/aids-infected adults / Fatores de risco associados à hipovitaminose D em indivíduos adultos infectados pelo HIV/aids

Objective To investigate risk factors associated with hypovitaminosis D in adult patients infected with HIV/aids, at a referral hospital in Maceió, Brazil. Subjects and methods This cross-sectional study involved 125 patients evaluated from April to September 2013 by means of interviews, review of medical records, physical examination, and laboratory tests. The data were analyzed using the SPSS® software, version 17.0; the prevalence of hypovitaminosis D and mean levels of vitamin D were determined. The association between hypovitaminosis D and the independent variables was assessed using the Chi-square or the Fisher’s exact tests; mean vitamin D concentrations were analyzed using Kolmogorov-Smirnov, Mann-Whitney, and Kruskal-Wallis tests. The level of significance was set at 5% across tests. Results The prevalence of hypovitaminosis D was 24%, with a significant association with higher household income (p < 0.05). Higher vitamin D levels were associated with female gender (p < 0.001), no use of sunscreen (p < 0.05), and previous opportunistic infections (p < 0.01). Lower values were associated with the use of antiretroviral medication (p < 0.05), overweight and obesity (p < 0.01). Conclusion Lower vitamin D concentrations were significantly associated with well-known risk factors for hypovitaminosis D: use of sunscreen, antiretroviral medication, overweight, and obesity. The prevalence of hypovitaminosis D in this study, considering values > 20 ng/mL or > 30 ng/mL as vitamin D sufficiency, was lower to that of previous studies with HIV-infected patients, a fact that might be related to the low latitude and high intensity of solar radiation of the location of the present study. .

Objetivo Investigar fatores de risco associados à hipovitaminose D em pacientes adultos infectados por HIV/aids, num centro de referência em Maceió-AL. Sujeitos e métodos Por meio de desenho transversal, 125 pacientes foram avaliados por entrevista, revisão de prontuário, exame físico e laboratorial, no período de abril a setembro de 2013. Os dados foram analisados por meio do software SPSS®, versão 17.0, sendo determinados a prevalência de hipovitaminose D e os níveis médios de vitamina D. Para avaliação da associação entre hipovitaminose D e as variáveis pesquisadas, foram utilizados o teste Qui-quadrado ou o teste exato de Fisher, enquanto para os níveis médios de vitamina D foram utilizados os testes Kolmogorov-Smirnov, Mann-Whitney e Kruskal-Wallis. O nível de significância foi de 5% para todos os testes. Resultados Foi observada prevalência de hipovitaminose D de 24% com associação significativa com maior renda familiar (p < 0,05); níveis de vitamina D mais altos nas mulheres (p < 0,001), em pacientes que não faziam uso de filtro solar (p < 0,05) e naqueles com infecções oportunistas pregressas (p < 0,01). Valores mais baixos foram associados ao uso de antirretrovirais (p < 0,05), sobrepeso e obesidade (p < 0,01). Conclusão Níveis mais baixos de vitamina D estiveram significativamente associados com tradicionais fatores de risco para hipovitaminose D como uso de filtro solar e antirretrovirais, sobrepeso e obesidade. A prevalência de hipovitaminose encontrada, considerando suficiência de vitamina D tanto para valores acima de 20 ng/mL quanto de 30 ng/mL, foi inferior a estudos anteriores em pacientes infectados pelo HIV, fato que pode estar relacionado às características da localidade do estudo, com baixa latitude e elevada incidência solar. .