Anti-serum validation for use in immunohistochemistry for Trypanosoma cruzi detection.

Introduction: The detection of Trypanosoma cruzi in tissue samples is important in many situations, such as testing of the reactivation of the infection. The detection of T. cruzi nests in endomyocardial biopsies (EMB) may be useful to evaluate graft rejection. Given their scarcity, such nests are not routinely identified. To increase the diagnosis sensitivity, immunohistochemistry (IHC) may serve as a promising strategy. Here, we validate an antiserum for the detection of T. cruzi infection by IHC. Methods: We used 1) positive controls (PCs) ? 13 EMB, 12 skin biopsies, and 1 heart with T. cruzi nests as sections stained with hematoxylin and eosin (HE); 2) negative controls ? a) 10 explant hearts and 10 EMB with no amastigote nests or clinical/laboratory signs of chagasic infection; and b) eight samples with leishmaniasis, toxoplasmosis, or histoplasmosis; and 3) Cases ? 31 EMB of chagasic patients with no parasite nests in HE sections but detected positive for T. cruzi DNA by polymerase chain reaction. As a primary antibody, a hyperimmune serum from T. cruzi-infected rabbits was used. Results: IHC results were positive for 21 of 26 PCs (80.8%) and one case of cutaneous leishmaniasis. In 4 of 31 cases, IHC revealed nests (12.9%), which were undetected by conventional histological examination. Conclusions: This study shows that IHC with the tested antiserum increases the sensitivity of the diagnosis and may be recommended for routine use in EMB analyses of cardiac transplant patients with Chagas disease

Factors that influence the occurrence and dispersion of iron minerals in sandy sediments of terraces and floodplains of rivers draining the Quadrilatero Ferrifero (MG).

Este trabalho apresenta os resultados de estudos sedimentol?gicos realizados ao longo dos cursos de ?gua das bacias hidrogr?ficas dos rios Piracicaba, das Velhas e Doce que drenam as ?reas das minas de ferro do Quadril?tero Ferr?fero. Foram realizadas caracteriza??es sedimentol?gicas e mineral?gicas de amostras coletadas na calha dos cursos de ?gua visando obter a concentra??o de minerais de ferro. Paralelamente, foram analisadas amostras de sedimentos coletados nas v?rzeas e terra?os, com objetivo de obter elementos de compara??o temporal da ocorr?ncia de minerais de ferro em sedimentos aluviais depositados anteriormente ? instala??o das minas na regi?o. Os resultados obtidos indicam que a presen?a de barramentos nos cursos de ?gua interfere na dispers?o dos minerais de ferro. A malha ferrovi?ria utilizada como escoamento da produ??o de ferro ao longo do rio Piracicaba atua como fonte secund?ria de minerais de ferro nas v?rzeas e na calha do rio. Quando comparados ? concentra??o de minerais de ferro nos terra?os, os sedimentos das calhas fluviais mostram substancial aumento da concentra??o, indicando que a a??o antr?pica ? a causadora deste aumento a despeito das a??es mitigadoras que a legisla??o ambiental preconiza.This work presents the results of sedimentological studies conducted along the watercourses of the Piracicaba, Velhas and Doce river basins that drain the iron mining areas of the Quadrilatero Ferr?fero. Sedimentological and mineralogical characterization of sandy sediment samples collected in the channel of the water courses was carried out in order to obtain the concentration of iron minerals. In addition, samples of sediments from the floodplains and terraces were collected and analyzed, with the pourpose of make temporal comparison among sandy iron mineral concentration in alluvial sediments deposited prior to the installation of the mines in the region. The results indicate that the presence of dams in the watercourses interferes with the dispersion of iron minerals. The railroad used in transport of the iron production along the Piracicaba river valley acts as a secondary source of iron minerals in the floodplains and in the river channel. When compared to the concentration of iron minerals in the terraces, the sediments of the river channels show a substantial increase in concentration, indicating that the anthropic action is the main cause of this increase despite mitigating actions regulated by environmental laws

The effect of benznidazole dose among the efficacy outcome in the murine animal model. A quantitative integration of the literature.

Despite more than 100 years since it was firstly described Chagas disease, only two drugs are available to treat Chagas disease: Nifurtimox launched by Bayer in 1965 and benznidazole launched by Roche in 1971. Drug discovery initiatives have been looking for new compounds as an alternative to these old drugs. Although new platforms have been used with the latest technologies, a critical step on that process still relies on the in vivo model. Unfortunately, to date, available animal models have limited predictive value and there is no standardization. With the aim to better understand the role of benznidazole, the current standard of care of Chagas disease, we performed this review. We intend to analyze the influence of the experimental design of the most used animal model, the murine model, in the assessment of the efficacy endpoint

Food insecurity, food waste, food behaviours and cooking confidence of UK citizens at the start of the COVID-19 lockdown

Purpose The current pilot study explored food insecurity, food waste, food related behaviours and cooking confidence of UK consumers following the COVID-19 lockdown. Design/methodology/approach Data were collected from 473 UK-based consumers (63% female) in March 2020. A cross-sectional online survey measured variables including food insecurity prevalence, self-reported food waste, food management behaviours, confidence and frequency of use of a range of cooking methods, type of food eaten (ultra-processed, semi-finished, unprocessed) and packaging type foods are purchased in. Findings 39% of participants have experienced some food insecurity in the last 12 months. Being younger, having a greater BMI and living in a smaller household were associated with food insecurity. Green leaves, carrots, potatoes and sliced bread are the most wasted of purchased foods. Polenta, green leaves and white rice are the most wasted cooked foods. Food secure participants reported wasting a smaller percentage of purchased and cooked foods compared to food insecure participants. Overall, participants were most confident about boiling, microwaving and stir-frying and least confident with using a pressure cooker or sous vide. Food secure participants were more confident with boiling, stir-frying, grilling and roasting than insecure food participants. Practical implications This has implications for post lockdown policy, including food policies and guidance for public-facing communications. Originality/value We identified novel differences in self-report food waste behaviours and cooking confidence between the food secure and insecure consumers and observed demographics associated with food insecurity

Predictors of HBeAg status and hepatitis B viraemia in HIV-infected patients with chronic hepatitis B in the HAART era in Brazil

<p>Abstract</p> <p>Background</p> <p>HBV-HIV co-infection is associated with an increased liver-related morbidity and mortality. However, little is known about the natural history of chronic hepatitis B in HIV-infected individuals under highly active antiretroviral therapy (HAART) receiving at least one of the two drugs that also affect HBV (TDF and LAM). Information about HBeAg status and HBV viremia in HIV/HBV co-infected patients is scarce. The objective of this study was to search for clinical and virological variables associated with HBeAg status and HBV viremia in patients of an HIV/HBV co-infected cohort.</p> <p>Methods</p> <p>A retrospective cross-sectional study was performed, of HBsAg-positive HIV-infected patients in treatment between 1994 and 2007 in two AIDS outpatient clinics located in the São Paulo metropolitan area, Brazil. The baseline data were age, sex, CD4 T+ cell count, ALT level, HIV and HBV viral load, HBV genotype, and duration of antiretroviral use. The variables associated to HBeAg status and HBV viremia were assessed using logistic regression.</p> <p>Results</p> <p>A total of 86 HBsAg patients were included in the study. Of these, 48 (56%) were using combination therapy that included lamivudine (LAM) and tenofovir (TDF), 31 (36%) were using LAM monotherapy, and 7 patients had no previous use of either one. Duration of use of TDF and LAM varied from 4 to 21 and 7 to 144 months, respectively. A total of 42 (48. 9%) patients were HBeAg positive and 44 (51. 1%) were HBeAg negative. The multivariate analysis revealed that the use of TDF for longer than 12 months was associated with undetectable HBV DNA viral load (serum HBV DNA level < 60 UI/ml) (<it>p </it>= 0. 047). HBeAg positivity was associated with HBV DNA > 60 UI/ml (p = 0. 001) and ALT levels above normality (<it>p </it>= 0. 038).</p> <p>Conclusion</p> <p>Prolonged use of TDF containing HAART is associated with undetectable HBV DNA viral load. HBeAg positivity is associated with HBV viremia and increased ALT levels.</p

Diversity of HIV-1 Subtype B: Implications to the Origin of BF Recombinants

BACKGROUND: The HIV-1 subtype B epidemic in Brazil is peculiar because of the high frequency of isolates having the GWGR tetramer at V3 loop region. It has been suggested that GWGR is a distinct variant and less pathogenic than other subtype B isolates. METHODOLOGY/PRINCIPAL FINDINGS: Ninety-four percent of the HIV-1 subtype B worldwide sequences (7689/8131) obtained from the Los Alamos HIV database contain proline at the tetramer of the V3 loop of the env gene (GPGR) and only 0.74% (60/8131) have tryptophan (GWGR). By contrast, 48.4% (161/333) of subtype B isolates from Brazil have proline, 30.6% (102/333) contain tryptophan and 10.5% (35/333) have phenylalanine (F) at the second position of the V3 loop tip. The proportion of tryptophan and phenylalanine in Brazilian isolates is much higher than in worldwide subtype B sequences (chi-square test, p = 0.0001). The combined proportion of proline, tryptophan and phenylalanine (GPGR+GWGR+GFGR) of Brazilian isolates corresponds to 89% of all amino acids in the V3 loop. Phylogenetic analysis revealed that almost all subtype B isolates in Brazil have a common origin regardless of their motif (GWGR, GPGR, GGGR, etc.) at the V3 tetramer. This shared ancestral origin was also observed in CRF28_BF and CRF29_BF in a genome region (free of recombination) derived from parental subtype B. These results imply that tryptophan substitution (e.g., GWGR-to-GxGR), which was previously associated with the change in the coreceptor usage within the host, also occurs at the population level. CONCLUSIONS/SIGNIFICANCE: Based on the current findings and previous study showing that tryptophan and phenylalanine in the V3 loop are related with coreceptor usage, we propose that tryptophan and phenylalanine in subtype B isolates in Brazil are kept by selective mechanisms due to the distinct coreceptor preferences in target cells of GWGR, GFGR and GFGR viruses