Malaria pigment crystals as magnetic micro-rotors: Key for high-sensitivity diagnosis

The need to develop new methods for the high-sensitivity diagnosis of malaria has initiated a global activity in medical and interdisciplinary sciences. Most of the diverse variety of emerging techniques are based on research-grade instruments, sophisticated reagent-based assays or rely on expertise. Here, we suggest an alternative optical methodology with an easy-to- use and cost-effective instrumentation based on unique properties of malaria pigment reported previously and determined quantitatively in the present study. Malaria pigment, also called hemozoin, is an insoluble microcrystalline form of heme. These crystallites show remarkable magnetic and optical anisotropy distinctly from any other components of blood. As a consequence, they can simultaneously act as magnetically driven micro-rotors and spinning polarizers in suspensions. These properties can gain importance not only in malaria diagnosis and therapies, where hemozoin is considered as drug target or immune modulator, but also in the magnetic manipulation of cells and tissues on the microscopic scale

Comunicação de risco em contexto municipal: Reflexões preliminares

Os contornos da atual realidade – global e isenta de fronteiras - onde o digital revolucionou relações interpessoais e noção de distância, democratizando o acesso ao conhecimento e melhorando a vida dos indivíduos, lançaram a sociedade num drama enraizado na sua própria atividade tecnocientífica, cujo estado normal ameaça tornar-se catastrófico, dado o seu caráter de vulnerabilidade, incerteza, complexidade e ambiguidade, e originando a denominada ‘sociedade de risco’.Neste paradoxo, reside a pertinência em estudar num contexto municipal o fluxo comunicacional, assim como os mecanismos de resposta a situações de risco da comunidade. Os objetivos do estudo são avaliar o esforço empregue na comunicação do risco pela autarquia e captar a perceção dos munícipes, quer do risco, quer da receção das mensagens e participação ativa nas decisões para a capacitação de um município alerta, consciente e capaz de agir preventivamente.Não existindo consenso entre técnicos, decisores e o público leigo em matéria de perceção do risco, urge comungar a noção de risco, simetrizando conteúdos entre peritos e desconhecedores. A prática de uma comunicação integrada do risco, estrategicamente voltada para públicos em diferentes níveis de consciência/informação, constitui-se como um meio eficaz para a capacitação populacional quanto à compreensão, avaliação e ação sobre os riscos a que pode, infortunadamente, estar sujeita. Esta comunicação aproxima-se do ideal de governança do risco, caracterizado por uma comunicação bilateral, na qualidade de canal de troca de (in)formações e opiniões entre os stakeholders para que, no fim, convirjam na tomada de decisão face aos comportamentos a implementar.Acreditando na comunicação como pedra basilar, apta a instituir as condições do relacionamento organis- mos-público, registam-se parcas investigações na área da comunicação estratégica, nomeadamente em contexto local, daí o interesse pela Vila de Mafra.Recorre-se a uma metodologia mista, usando ferramentas de pesquisa qualitativas – como uma auditoria à comunicação da Câmara; análise SWOT; mapeamento de stakeholders; entrevistas a responsáveis pela tomada de decisão, governança e comunicação do risco – e quantitativas – com o inquérito a uma amostra da população mafrense.Em resultado queremos aferir as dúvidas da comunidade mafrense no que concerne à comunicação rececionada para a sua capacitação, assim como qual a abertura à sua opinião sobre a legitimidade das decisões tomadas em situação de risco. Esperamos auxiliar no (re)estabelecimento de uma comunicação estratégica fluida e mútua entre a Câmara Municipal e a comunidade envolvente, corroborando a grande responsabilidade que justifica a sua existência neste município.N/

Effect of ionizing radiation exposure on Trypanosoma cruzi ubiquitin-proteasome system

In recent years, proteasome involvement in the damage response induced by ionizing radiation (IR) became evident. However, whether proteasome plays a direct or indirect role in IR-induced damage response still unclear. Trypanosoma cruzi is a human parasite capable of remarkable high tolerance to IR, suggesting a highly efficient damage response system. Here, we investigate the role of T. cruzi proteasome in the damage response induced by IR. We exposed epimastigotes to high doses of gamma ray and we analyzed the expression and subcellular localization of several components of the ubiquitin-proteasome system. We show that proteasome inhibition increases IR-induced cell growth arrest and proteasome-mediated proteolysis is altered after parasite exposure. We observed nuclear accumulation of 19S and 20S proteasome subunits in response to IR treatments. Intriguingly, the dynamic of 19S particle nuclear accumulation was more similar to the dynamic observed for Rad51 nuclear translocation than the observed for 20S. In the other hand, 20S increase and nuclear translocation could be related with an increase of its regulator PA26 and high levels of proteasome-mediated proteolysis in vitro. The intersection between the opposed peaks of 19S and 20S protein levels was marked by nuclear accumulation of both 20S and 19S together with Ubiquitin, suggesting a role of ubiquitin-proteasome system in the nuclear protein turnover at the time. Our results revealed the importance of proteasome-mediated proteolysis in T. cruzi IR-induced damage response suggesting that proteasome is also involved in T. cruzi IR tolerance. Moreover, our data support the possible direct/signaling role of 19S in DNA damage repair. Based on these results, we speculate that spatial and temporal differences between the 19S particle and 20S proteasome controls proteasome multiple roles in IR damage response. (C) 2017 Elsevier B.V. All rights reserved.CNPq - BrazilFAPEMIGPRONEXNewton Fund/FAPEMIGFAPESPUniv Fed Minas Gerais, Inst Ciencias Biol, Dept Bioquim Imunol, Belo Horizonte, MG, BrazilUniv Fed Sao Paulo, Dept Microbiol Imunol Parasitol, Sao Paulo, BrazilUniv Fed Ouro Preto, Inst Ciencias Exatas Biol, Dept Ciencias Biol & Nucleo Pesquisa Ciencias Bio, Ouro Preto, BrazilInst Carlos Chagas, FIOCRUZ, Curitiba, Parana, BrazilInst Biol Mol Parana, Curitiba, Parana, BrazilUniv Fed Sao Paulo, Dept Microbiol Imunol Parasitol, Sao Paulo, BrazilCNPq: 444334/2014-9FAPEMIG: APQ-00827-15Web of Scienc

Agglomerates Containing Pantoprazole Microparticles: Modulating the Drug Release

Pantoprazole-loaded microparticles were prepared using a blend of Eudragit® S100 and Methocel® F4M. The accelerated stability was carried out during 6 months at 40°C and 75% relative humidity. In order to improve technological characteristics of the pantoprazole-loaded microparticles, soft agglomerates were prepared viewing an oral delayed release and gastro-resistant solid dosage form. The agglomeration was performed by mixing the pantoprazole microparticles with spray-dried mannitol/lecithin powders. The effects of factors such as the amount of lecithin in the spray-dried mannitol/lecithin powders and the ratio between pantoprazole microparticles and spray-dried mannitol/lecithin powders were evaluated. The pantoprazole-loaded microparticles present no significant degradation in 6 months. The agglomerates presented spherical shape, with smooth surface and very small quantity of non-agglomerated particles. The agglomerates presented different yields (35.5–79.0%), drug loading (58–101%), and mechanical properties (tensile strength varied from 44 to 69 mN mm−2), when the spray-dried mannitol/lecithin powders with different lecithin amounts were used. The biopharmaceutical characteristics of pantoprazole microparticles, i.e., their delayed-release properties, were not affected by the agglomeration process. The gastro-resistance of the agglomerates was affected by the amount of spray-dried mannitol/lecithin powders. The ratio of lecithin in the spray-dried mannitol/lecithin powders was the key factor in the agglomerate formation and in the drug release profiles. The agglomerates presenting better mechanical and biopharmaceutical characteristics were prepared with 1:2 (w/w) ratio of pantoprazole-loaded microparticles and mannitol/lecithin (80:20) powder