Abstract INTRODUCTION: Hepatitis B virus (HBV) infection is a public health problem; therefore, we aimed to report HBV genotypes in Ceará, Brazil. METHODS: A total of 103 HBsAg-positive samples were subjected to HBV genotyping and subgenotyping. RESULTS: The following genetic compositions of samples were found: F-54% (F2-83.33%), A-40% (A1-65%), D-6%, C2-1%, E-1%, and G-1%. CONCLUSIONS: Some genotypes are only prevalent in certain parts of the world; however, the State of Ceará is a hub for migration and has one of the most important liver transplantation centers in Brazil, which can explain the prevalence of the F genotype.

ABSTRACT: The measurements obtained by remote sensing are influenced by issues related to relief. Based on that, this paper aims to analyze the spatial and temporal dynamics of the net radiation (Rn), considering the influence of topographic parameters on it, in Edgárdia Experimental Farm (FEE). It was used the methodology based on the SEBAL algorithm (Surface Energy Balance Algorithm for Land) to estimate the net radiation by orbital images. In order to assess the topographic influence on the computing of net radiation, three methodologies were applied: without topographic correction (RnSem), cosine correction (RnCos) and C correction (RnC). These methodologies were applied on 21 images of the orbital platform Landsat-5/TM, from 1985 up to 2010. Due to the complex relief of the FEE, the cosine correction did not show effectiveness on the attenuation of topographic influence. For the values of RnC, we noticed an average reduction of 5.97% for the standard deviation, relative to the images without correction. These results show the importance of considering the relief, to achieve higher accuracies on the estimation of biophysical parameters with orbital images.

Abstract INTRODUCTION Maytenus guianensis is a member of the Celastraceae family that is used in traditional medicine, particularly for its anti-parasitic and anti-cancer effects. To explore the ethnopharmacological potential of this plant, the present study was designed to screen the in vitro antileishmanial activities of extracts and compounds isolated from M. guianensis. METHODS Maytenus guianensis stems and leaves were extracted in acetone, followed by the preparation of eluates and isolation of secondary metabolites using chromatography on a glass column with silica gel as the fixed phase. The chemical components were identified using spectroscopic methods, including one- and two-dimensional nuclear magnetic resonance of hydrogen-1 and carbon-13, mass spectroscopy, and infrared spectroscopy. The anti-Leishmania amazonensis activities of these eluates and compounds were evaluated by direct promastigote counting and viability assays. RESULTS It was found that the hexane bark eluate produced the strongest anti-L. amazonensis effect, with 90-100% inhibition of the promastigote form. The isolated metabolite that produced the best result was tingenone B, followed by a compound formed by the union of tingenone and tingenone B (80-90% inhibition). CONCLUSIONS Maytenus guianensis shows anti-parasite activity that warrants further investigation to determine the mechanisms underlying this antileishmanial effect and to evaluate the pharmacological potential of these eluates and isolated secondary metabolites, while minimizing any adverse effects.

Hepatitis D virus (HDV) is endemic in the Amazon Region and its pathophysiology is the most severe among viral hepatitis. Treatment is performed with pegylated interferon and the immune response appears to be important for infection control. HDV patients were studied: untreated and polymerase chain reaction (PCR) positive (n = 9), anti-HDV positive and PCR negative (n = 8), and responders to treatment (n = 12). The cytokines, interleukin (IL)-2 (p = 0.0008) and IL-12 (p = 0.02) were differentially expressed among the groups and were also correlated (p = 0.0143). Future studies will be conducted with patients at different stages of treatment, associating the viral load with serum cytokines produced, thereby attempting to establish a prognostic indicator of the infection.

The retrovirus human T lymphotropic virus type 1 (HTLV-1) promotes spastic paraparesis, adult T cell leukaemia and other diseases. Recently, some human microRNAs (miRNAs) have been described as important factors in host-virus interactions. This study compared miRNA expression in control individuals, asymptomatic HTLV-1 carriers and HTLV-1 associated myelopathy (HAM)/tropical spastic paraparesis patients. The proviral load and Tax protein expression were measured in order to characterize the patients. hsa-miR-125b expression was significantly higher in patients than in controls (p = 0.0285) or in the HAM group (p = 0.0312). Therefore, our findings suggest that miR-125b expression can be used to elucidate the mechanisms of viral replication and pathogenic processes.

Toll-like receptors (TLRs) recognise pathogen-derived molecules and influence immunity to control parasite infections. This study aimed to evaluate the mRNA expression of TLRs 2 and 4, the expression and production of the cytokines interleukin (IL)-12, interferon (IFN)-γ, tumor necrosis factor (TNF)-α, IL-17, IL-10 and transforming growth factor (TGF)-β and the production of nitric oxide (NO) in the spleen of mice infected with Leishmania chagasi. It also aimed to evaluate any correlations between mRNA expression TLR2 and 4 and cytokines and NO production. Infection resulted in increased TLR2-4, IL-17, TNF-α and TGF-β mRNA expression during early infection, with decreased expression during late infection correlating with parasite load. IFN-γ and IL-12 mRNA expression decreased at the peak of parasitism. IL-10 mRNA expression increased throughout the entire time period analysed. Although TGF-β, TNF-α and IL-17 were highly produced during the initial phase of infection, IFN-γ and IL-12 exhibited high production during the final phase of infection. IL-10 and NO showed increased production throughout the evaluated time period. In the acute phase of infection, there was a positive correlation between TLR2-4, TNF-α, IL-17, NO, IL-10 and TGF-β expression and parasite load. During the chronic phase of infection, there was a positive correlation between TLR2-4, TNF-α, IL-17 and TGF-β expression and parasite load. Our data suggest that infection by L. chagasi resulted in modulation of TLRs 2 and 4 and cytokines.