Riscos na qualidade sanitária da carne de jacaré da Amazônia Central

Determining caiman meat quality is a major problem when establishing the production chain of wild populations. In Brazil, there are no protocols for this type of meat. The slaughter and processing were performed using a simplified, traditional floating raft system and a water treatment system that used both filtration and chemicals. The animals were caught using a hook, harpoon, resting pole, and cable snare. The wild caimans of two species (Melanosuchus niger and Caiman crocodilus) were captured in the region of the Piagaçu-Purus Sustainable Development Reserve in Central Amazon during three harvesting events. After each event, we progressively improved the meat-processing protocol. Microbiological testing of the meat was performed as described in norms and Brazilian legislation for fish meat. As a result, we achieved improvements in the sanitary quality of the meat of the killed animals for 57%, 76.5% and 100% of the samples obtained during the first, second, and third harvesting events, respectively. There were significant differences in the microbiological quality of the meat, with a reduction in the disapproval of the samples. The process of capturing animals, the cable snare, and the restraining pole were the factors that least affected the quality of the meat; in addition, animals between 81 and 100 cm of CRC had a lower risk of microbiological contamination. We can conclude that health surveillance activities, such as hand hygiene when handling meat, improvements in water quality, selection of animals of the most appropriate size for slaughter, and capture by less invasive methods can reduce the potential for microbiological contamination of the meat contribute to decrease the potential for microbiological contamination of meat.A determinação da qualidade sanitária da carne de jacaré é um dos principais problemas no estabelecimento da cadeia produtiva deste animal, pois não existem protocolos no Brasil para esse tipo de carne. O abate e processamento da carne foram realizados em sistema simplificado e artesanal em balsa flutuante, com sistema de tratamento de água por filtração e produtos químicos. Os animais foram capturados por anzol, arpão, cambão e laço. Foram capturados animais de vida silvestre na região da Reserva de Desenvolvimento Sustentável Piagaçu-Purus, na Amazônia Central, das espécies Melanosuchus niger e Caiman crocodilos, em três eventos de abate, com melhoria progressiva no protocolo de beneficiamento da carne. Foram feitas análises microbiológicas da carne, conforme descrito em normas e legislações brasileiras para a carne de pescado. Como resultados da pesquisa obtivemos melhorias na qualidade microbiológica da carne dos animais abatidos, conforme as medidas de vigilância sanitária que foram adotadas, passando de 57% de amostras aprovadas no 1º lote de abate para 76,5% no 2º lote e, no final, para 100% no 3º lote. Ocorreram diferenças significativas no comprometimento da qualidade sanitária da carne, com diminuição das reprovações das amostras. Os processos de captura dos animais, laço e cambão foram os que menos comprometeram a qualidade da carne, e animais com tamanho na faixa de 81 a 100 cm de CRC foram os que apresentaram menor risco de contaminação microbiológica. Podemos concluir que ações de vigilância sanitária como: higienização das mãos durante a manipulação da carne, melhorias na qualidade da água, abate de animais no tamanho mais adequado e captura por métodos menos invasivos contribuem para diminuição dos riscos potenciais de contaminação microbiológica da carne

Expression Atlas update: from tissues to single cells.

Expression Atlas is EMBL-EBI's resource for gene and protein expression. It sources and compiles data on the abundance and localisation of RNA and proteins in various biological systems and contexts and provides open access to this data for the research community. With the increased availability of single cell RNA-Seq datasets in the public archives, we have now extended Expression Atlas with a new added-value service to display gene expression in single cells. Single Cell Expression Atlas was launched in 2018 and currently includes 123 single cell RNA-Seq studies from 12 species. The website can be searched by genes within or across species to reveal experiments, tissues and cell types where this gene is expressed or under which conditions it is a marker gene. Within each study, cells can be visualized using a pre-calculated t-SNE plot and can be coloured by different features or by cell clusters based on gene expression. Within each experiment, there are links to downloadable files, such as RNA quantification matrices, clustering results, reports on protocols and associated metadata, such as assigned cell types

Pulsed magnetic field-induced twin boundary motion on Ni-Mn-Ga

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2003.Includes bibliographical references (p. 201-210).The magnetic field-induced strain (ferromagnetic shape memory effect - FSME) in Ni-Mn-Ga was first reported in 1996 by Ullakko et al. Since then, up to 6% FSME in single-crystal tetragonal-Ni-Mn-Ga samples has been observed in static fields, and up to 3% at 500 Hz. The present work demonstrates 6% FSME of a Ni-Mn-Ga single crystal of 5 x 5 x 9.85 mm³ in 200[mu]s is by application of a magnetic field pulse. It proves the feasibility of actuators operating at frequencies above of 1 kHz at room temperature for this geometry, and that the actuation can be accomplished using compact, air-core Helmholtz coils operated in pulsed mode. The eddy-current attenuation of 620 [mu]s-long pulses in the samples tested is small, reducing the need for lamination. The field-induced extension does not begin at the same time as the field. Part of the delay is the time that the field takes to reach the threshold level for actuation. The mass-inertia of the sample results in an additional delay, which depends on the position and number of mobile twin-boundaries in the crystal. The delay is maximum for a single twin-boundary moving from the fixed to the free end of the crystal. For several twin-boundaries distributed uniformly throughout the crystal the delay is shorter. The peak acceleration observed is 50 ± 10 m/s². For typical twin-boundary energies of the order of 40 erg/cm² homogeneous nucleation of partial dislocations was found to be unlikely. Accordingly, twin-boundaries must be seeded through stress. High-speed video images and photographs have demonstrated that field-induced twin-boundary motion is not uniform along a Ni-Mn-Ga single crystal. Twin boundaries stop when they reach certain positions of the crystal, and remain pinned unless the field is increased. The observed scatter in the data of field-induced extension is related to the existence of pinning sites. The maximum rate of extension can be expressed as an exponential function of the driving force, andreaches 6 m/s for saturated driving force in the present case.by Miguel Augusto Marioni.Ph.D

Mercury concentration in the spectacled caiman and black caiman (Alligatoridae) of the Amazon: Implications for human health

Mercury (Hg) concentrations in the Amazon are generally high, but no studies have been published on Hg concentrations in caimans (Alligatoridae) from the region. Aiming for sizes representative of caimans traded for food in the Amazon, we measured Hg concentration in tail muscle of spectacled caiman (Caiman crocodilus crocodilus) and black caiman (Melanosuchus niger) from the Purus River basin. The information on Hg concentration in caimans from this area is important because of the potential health risk to humans and other animals that eat them as well as the potential use of these top-level predators as bioindicators. There were no significant interspecific or sex differences in Hg concentrations. The mean Hg concentration was 291.2 μg/kg in C. c. crocodilus and 193.9 μg/kg in M. niger. A significant positive correlation between Hg concentration and size was found for M. niger (p = 0.005) but not for C. c. crocodilus. Our Hg sample from M. niger corresponded to the size of M. niger collected for commercial trade, but our Hg sample from C. c. crocodilus turned out to be significantly smaller than the trade samples (p = 0.004), but this difference is not pertinent in the absence of a correlation between size and Hg concentration for this species. Although there are no standards for reptile meat, both species had mean Hg concentrations lower than the maximum allowable level of 500 μg/kg Hg recommended by the World Health Organization and by the Brazilian Health Ministry for fish. However, by calculating daily consumptions limits and number of meals per month that can be safely consumed, we found that consumers who eat caimans frequently may be at risk for Hg-related health problems. © Springer Science+Business Media, LLC 2012

Liver retransplantation in adults: a 20–year experience of one center in southern Brazil

Introduction. Liver retransplantation (LReTx) is the therapeutic option for hepatic graft failure. Survival after LReTx is poorer than after primary liver transplantation. Given the organ shortage, it is essential to optimize the use of this resource.Objective. To evaluate rates, indications and patient survival after LReTx and identify factors associated with mortality following LReTx.Material and methods. We conducted a retrospective cohort study of all adults undergoing LReTx based on registry data from the Liver Transplantation Group (Complexo Hospitalar Santa Casa de Porto Alegre), southern Brazil.Results. Between June 16, 1991 and July 19, 2011, 824 patients underwent 866 liver transplants. Forty-two procedures corresponded to LReTx (4.8% of all liver transplants performed). Thirty-eight patients who underwent a single LReTx procedure were included in this study. The leading indication for LReTx was hepatic artery thrombosis (HAT) (31.6%), followed by primary nonfunction (PNF) (18.4%). The main indication for early LReTx was PNF (58.3%) and for late LReTx was HAT (38.5%). During the follow-up period, 26 patients (68.4%) died after LReTx. Patient survival at 1 and 3 years after LReTx was 44.7% and 44.7%, respectively. Patients infected with hepatitis C virus, serum albumin < 2.5 g/dL and receiving mechanical ventilation immediately before LReTx had a significantly lower survival rate than the other patients.Conclusion. Considering the increased mortality when the graft loss is delayed, it is necessary to define the minimum acceptable results to indicate LReTx and identify the patients who would most benefit from this treatment