RESUMO
There are several phenolic compounds in rice grains providing benefits for human health. The concentration of phenolic compounds in rice is strongly affected by the polishing steps during rice production. A new sensitive ultraperformance liquid chromatography-ultraviolet-visible spectroscopy method with a photodiode array detection protocol has been developed and validated for the quantitation of phenolic compounds in rice grains. Several working variables and two different columns were evaluated. Finally, a less than 3 min analysis time was developed to achieve enough resolution for the simultaneous determination of the 20 most common phenolic compounds in rice. The analytical properties for the separation method produced an adequate sensitivity for all phenolic compounds in the regular range for phenolics in rice, 0.5-100 mg L-1 ( R2 > 0.997), with high precisions for both repeatability and intermediate precisions (coefficients of variation less than 0.4 and 2.5% for the retention time and area of the peaks, respectively).
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Oryza/química , Fenóis/análise , Extratos Vegetais/análise , Sementes/química , Cromatografia Líquida de Alta Pressão/instrumentaçãoRESUMO
OBJECTIVE: Reports have suggested that human T-cell lymphotropic virus type 1 (HTLV-1) may influence immunological response and therefore the clinical course of tuberculosis (TB) in co-infected individuals. We wished to determine the prevalence of HTLV-1 infection among hospitalized patients in Salvador, Brazil, a region endemic for both HTLV-1 infection and latent TB infection. DESIGN: A cross-sectional study was conducted at a pulmonary disease hospital between 1 September 2006 and 31 August 2007. Study participants were interviewed and tested for HTLV-1 infection and current or past episode of TB. RESULTS: Of 607 participants recruited into the study, 360 (59.3%) had a current or past history of TB and 50 (8.2%) had HTLV-1 infection; 39 (6.4%) had both. After controlling for confounding variables, we found that the odds of patients with a positive HTLV-1 test having TB were 2.6 times the odds in those who tested negative for HTLV-1 infection (95%CI 1.2-5.4). CONCLUSION: In a region endemic for both TB and HTLV-1 infection, HTLV-1 infection increases the risk of Mycobacterium tuberculosis infection. Such a risk may influence TB transmission and the epidemiology of the disease in this community.