Analysis of genetic susceptibility to mercury contamination evaluated through molecular biomarkers in at-risk amazon amerindian populations

We investigated Individual differences in susceptibility to methylmercury (MeHg) contamination and its relationship with polymorphisms of the detoxifying enzyme glutathione S-transferase (GST). In Brazil, some Amerindian tribes from the Amazon region have an increased level of mercury in their hair. Samples of hair and blood were taken from inhabitants of two villages in the Kayabi and Munduruku Amerindian communities to investigate mercury levels in association with genetic polymorphism of GSTs. Other molecular biological markers were also studied, such as hemoglobin, haptoglobin and glucose 6-phosphate dehydrogenase (G-6-PDH). Higher levels of mercury contamination were found in the Kayabi villagers, who had a null genotype (GSTM1 0/0, also denominated GSTM1 null) frequency of 26%, than in the Munduruku villagers, for which the null genotype frequency was 0%. Individuals with the GSTM1 null phenotype had higher concentrations of mercury in their hair than individuals with GSTM1+/+ phenotypes (F = 21.51, p < 0.0001). No association with other markers studied was observed. This study suggests that GSTM1 may be involved in the biotransformation of mercury in humans

Ações de gestão ambiental: o caso da Embrapa Pecuária Sudeste.

Fatores de degradação ambiental como desmatamentos, queimadas, eliminação de áreas verdes permanentes que atuam como umidificadores do ar e estabilizadores térmicos, práticas agrícolas não conservacionistas com perda da capacidade produtiva dos solos e impedimento na recarga adequada de lençóis freáticos, aumento da produção de dejetos e rejeitos, consumismo e ruptura no conhecimento da sociedade urbana sobre sua dependência do meio natural resultam na redução da biodiversidade, no aumento de pragas e patógenos e nas mudanças climáticas regionais e global. Várias são as ações de gestão ambiental que podem minimizar estes efeitos. O presente trabalho tem por objetivo relatar e descrever as experiências relacionadas à gestão ambiental realizadas pela Embrapa Pecuária Sudeste. A metodologia utilizada é a de estudo de caso, que envolve a obtenção de dados descritivos por meio da observação direta e entrevista com os participantes da ação

Attention&ndash;memory training yields behavioral and academic improvements in children diagnosed with attention-deficit hyperactivity disorder comorbid with a learning disorder

BackgroundRecent studies have suggested that children with attention-deficit hyperactivity disorder (ADHD) may benefit from computerized cognitive training. Therapy implementation is especially complicated when ADHD is associated with learning disorders (LDs). This study tested the efficacy of a computer-based cognitive training program, namely, computerized cognitive training (CCT), in children with ADHD comorbid with an LD (ADHD-LD), with or without psychostimulant medication.Materials and methodsAfter diagnostic evaluations, 27 children with ADHD-LD (8 unmedicated and 19 medicated) participated in CCT, which is intended to improve attention, memory, reasoning, visual processing, and executive functioning. The participants completed 24 1-hour sessions over 3 months. Neuropsychometric and standardized academic test results before and after training were compared to assess treatment efficacy. Shapiro-Wilk normality tests were applied, and subsequent Wilcoxon tests were used to identify significant differences in pre-versus post-training performance.ResultsAfter CAT, children diagnosed with ADHD-LD showed 1) improvements in trained skills, measured directly within the software and indirectly by external psychometric tests; 2) improvements in attention, memory, and some executive functioning; 3) improvements in academic performance, particularly in mathematics; and 4) reductions in maladaptive behavioral features.ConclusionThe present findings suggest that cognitive training programs should be explored further as potential adjunctive therapies to improve outcomes in children with ADHD-LD

Potential link between caffeine consumption and pediatric depression: A case-control study

<p>Abstract</p> <p>Background</p> <p>Early-onset depressive disorders can have severe consequences both from developmental and functional aspects. The etiology of depressive disorders is complex and multi-factorial, with an intricate interaction among environmental factors and genetic predisposition. While data from studies on adults suggest that caffeine is fairly safe, effects of caffeine in children, who are in period of rapid brain development, are currently unknown. Furthermore, systematic research addressing the relationship between depressive symptoms in children and caffeine consumption is lacking.</p> <p>The present study examined the effects of caffeine consumption on depressed mood in children with depression and non-depressed participants.</p> <p>Methods</p> <p>Children and adolescents (n = 51) already enrolled in an ongoing longitudinal study, aged 9-12 years, were assessed for depressive symptoms with the Children Depressive Inventory (CDI). Psychopathological symptoms were assessed with the Child Behavioral Checklist (CBCL) and eating habits were assessed with the Nutrition-Behavior Inventory (NBI) <abbrgrp><abbr bid="B1">1</abbr></abbrgrp>. The children were compared to control children without psychopathology attending public schools in a Southern Brazilian city.</p> <p>Results</p> <p>Participants with CDI scores ≥ 15 (mean = 19; S.D. = 4) also had high NBI scores (mean = 52; S.D. = 19, p < 0.001) suggestive of a relationship between depressive symptoms and environmental factors, in this case nutrition/behavior. Additional linear regression adjusted statistical analysis, considering the factors of consumption of sweets and caffeine individually, showed that caffeine, but not sweets, was associated with depressive symptoms.</p> <p>Conclusions</p> <p>These findings indicate that depressed children consume more caffeinated drinks than non-depressed children. Nonetheless while a strong association between depressive symptoms and caffeine consumption among children was found, further research should investigate whether or not this association is due to a cause and effect relationship.</p

Valoración de la actividad biológica de nuevas formulaciones farmacéuticas de nifurtimox y anfotericina B

Los fármacos utilizados contra la Enfermedad de Chagas y Leishmaniasis están asociados a severos efectos secundarios. El desarrollo de nuevas drogas activas o mejorar las existentes constituye una necesidad prioritaria. Por este motivo, este proyecto desarrollo 7 nuevas formulaciones SNEDDS de nifurtimox y una formulación de microesferas de albumina de anfotericina B para ser ensayados in vitro e in vivo contra T. cruzi y Leishmania sp,respectivamente. De las 7 formulaciones NfxS, 3 fueron activas in vitro y una de ellas fue ensayada in vivo con una actividad parasitaria del 100%. La nueva formulación Anfo Bma fue un tratamiento intravenoso en 6 perros naturalmente infectados con L. infantum y solo 1 de ellos presento cura parasitológica.CONACYT – Consejo Nacional de Ciencia y TecnologíaPROCIENCI

Indirect DNA Readout by an H-NS Related Protein: Structure of the DNA Complex of the C-Terminal Domain of Ler

Ler, a member of the H-NS protein family, is the master regulator of the LEE pathogenicity island in virulent Escherichia coli strains. Here, we determined the structure of a complex between the DNA-binding domain of Ler (CT-Ler) and a 15-mer DNA duplex. CT-Ler recognizes a preexisting structural pattern in the DNA minor groove formed by two consecutive regions which are narrower and wider, respectively, compared with standard B-DNA. The compressed region, associated with an AT-tract, is sensed by the side chain of Arg90, whose mutation abolishes the capacity of Ler to bind DNA. The expanded groove allows the approach of the loop in which Arg90 is located. This is the first report of an experimental structure of a DNA complex that includes a protein belonging to the H-NS family. The indirect readout mechanism not only explains the capacity of H-NS and other H-NS family members to modulate the expression of a large number of genes but also the origin of the specificity displayed by Ler. Our results point to a general mechanism by which horizontally acquired genes may be specifically recognized by members of the H-NS family

The influence of rice husk ash addition on the properties of metakaolin-based geopolymers

This paper investigates the replacement of metakaolin (MK) with rice husk ash (RHA) in the production of alkali-activated binders or geopolymers. The influence of the RHA addition on compressive and flexural strength, as well as water absorption and apparent porosity were determined, in terms of the percentage of RHA in the mixture and molar ratios of the mixes. Fourier Transform Infrared (FTIR) spectroscopy and Energy Dispersive spectroscopy (EDS) were carried out to assess the changes in the microstructure of the geopolymer matrices with the RHA addition. Results have shown that RHA may be a supplementary precursor for geopolymers. The composition of the geopolymer matrices containing 0-40% RHA is very similar, which indicates that the additional Si provided by RHA is not incorporated to the geopolymer matrix. In addition, geopolymers with RHA content higher than 40% present a plastic behavior, characterized by extremely low strength and high deformation, which can be attributed to the formation of silica gel in formulations containing variable Si/Al ratio