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The diet of the gracile mouse opossum Gracilinanus microtarsus was studied in a cerrado remnant in south-eastern Brazil through the analysis of faeces sampled from adult individuals. Patterns of food resource consumption were assessed using the statistics of per cent occurrence. Intrapopulation variation in the number of food items detected in faeces as a function of relevant factors was inferred using generalized linear models. The latter statistical formalism also allowed variation in the number of food items detected in faeces to be interpreted in terms of rate ratios among levels of significant factors. Insects, spiders, snails and fruits were detected in the faeces of G. microtarsus, with insects, particularly termites, beetles and ants, being the most frequently detected food resource. These food resources were consumed in proportion to their relative abundance in the cerrado, suggesting that G. microtarsus is an opportunistic forager feeding primarily on insects. The generalized linear model identified sex, season and food resource as significant factors affecting the number of food items detected in faeces, as well as interactions between sex and season and season and food resource. Rate ratios calculated between sexes within seasons showed that the number of food items detected in the faeces of males was larger than that detected in the faeces of females in the warmwet and cool-dry seasons. Rate ratios calculated between seasons within sexes showed different trends in the number of food items detected in faeces for each significant food resource. It is suggested that differences in the number of food items detected in faeces between sexes within season and between seasons within sexes are related to energetic requirements associated with reproduction.

The chromosomal ends of Leishmania (Leishmania) amazonensis contain conserved 5¢-TTAGGG-3¢ telomeric repeats. Protein complexes that associate in vitro with these DNA sequences, Leishmania amazonensis G-strand telomeric protein (LaGT1-3), were identified and characterized by electrophoretic mobility shift assays and UV cross-linking using protein fractions purified from S100 and nuclear extracts. The three complexes did not form (a) with doublestranded DNA and the C-rich telomeric strand, (b) in competition assays using specific telomeric DNA oligonucleotides, or (c) after pretreatment with proteinase K. LaGT1 was the most specific and did not bind a Tetrahymena telomeric sequence. All three LaGTs associated with an RNA sequence cognate to the telomeric G-rich strand and a complex similar to LaGT1 is formed with a double-stranded DNA bearing a 3¢ G-overhang tail. The protein components of LaGT2 and LaGT3 were purified by affinity chromatography and identified, after renaturation, as 35 and 52 kDa bands, respectively. The £ 15 kDa protein component of LaGT1 was gel-purified as a UV cross-linked complex of 18-20 kDa. Peptides generated from trypsin digestion of the affinity and gel-purified protein bands were analysed by matrix-assisted laser desorption/ ionization-time of flight and electrospray ionization tandem mass spectrometry. The fingerprint and amino acid sequence analysis showed that the protein components of LaGT2 and of LaGT3 were, respectively, similar to the kinetoplastid Rbp38p and to the putative subunit 1 of replication protein A of Leishmania spp., whereas the £ 15 kDa protein component of LaGT1 was probably a novel Leishmania protein.Keywords: affinity purification; EMSA; Leishmania amazonensis; mass spectrometry; telomeric proteins.In almost all eukaryotes, including the pathogenic protozoan Leishmania (Leishmania) amazonensis, telomeres are nucleoprotein complexes formed by tandem repeats of conserved DNA sequences associated with proteins [1,2]. One of the telomere strands is G-rich and runs 5¢ fi 3¢ towards the end of the chromosomes, where it forms a single-stranded protrusion or 3¢ G-overhang [3]. The G-rich strand is the substrate for telomerase and for other telomere binding proteins involved in telomere length regulation and maintenance [4,5]. The length of this G-rich telomere extension appears to be cell cycle regulated in humans and yeast [6][7][8] and its loss leads to genome instability and chromosomal end fusion through the activation of DNA damage checkpoints [5,9].Proteins associated with both double-stranded and G-rich single-stranded telomeric DNA and with accessory proteins have been described in many eukaryotes. These proteins form a high order nucleoprotein complex that functions mainly to maintain the genome stability by regulating telomerase activity, the expression of genes positioned at telomeres, and the capping of chromosome ends to protect them from degradation and fusions [10,11]. For example, during the S phase, which is the period of increased single-strand extensi...

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Despite technological advances in efficiency enhancement of quantification assays, biomedical studies on HIV RNA collect viral load responses that are often subject to detection limits. Moreover, some related covariates such as CD4 cell count may be often measured with errors. Censored non-linear mixed-effects models are routinely used to analyze this type of data and are based on normality assumptions for the betweensubject and within-subject random terms. However, derived inference may not be robust when the underlying normality assumptions are questionable, especially in presence of skewness and heavy tails. In this article, we address these issues simultaneously under a Bayesian paradigm through joint modeling of the response and covariate processes using an attractive class of skew-normal independent densities. The methodology is illustrated using a case study on longitudinal HIV viral loads. Diagnostics for outlier detection is immediate from the MCMC output. Both simulation and real data analysis reveal the advantage of the proposed models in providing robust inference under non-normality situations commonly encountered in HIV/AIDS or other clinical studies.Supplementary materials accompanying this paper appear on-line.

Background: In Brazil coronary heart disease (CHD) constitutes the most important cause of death in both sexes in all the regions of the country and interestingly, the difference between the sexes in the CHD mortality rates is one of the smallest in the world because of high rates among women. Since a question has been raised about whether or how the incidence of several CHD risk factors differs between the sexes in Brazil the prevalence of various risk factors for CHD such as high blood cholesterol, diabetes mellitus, hypertension, obesity, sedentary lifestyle and cigarette smoking was compared between the sexes in a Brazilian population; also the relationships between blood cholesterol and the other risk factors were evaluated.

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Genomics, Hamming distance, Martingale, Orthogonal system, Permutation measure, Second-order asymptotics, Higher order decomposability,