Biochemical capacitance of geobacter sulfurreducens biofilms

An electrical model able to decouple the electron pathway from microbial cell machinery impedance terms is introduced. In this context, capacitance characteristics of the biofilm are clearly resolved. In other words, the model allows separating, according to the advantage of frequency and spectroscopic response approach, the different terms controlling the performance of the microbial biofilm respiratory process and thus the directly related electricity production process. The model can be accurately fitted to voltammetry measurements obtained under steady-state conditions and also to biofilm discharge amperometric measurements. The implications of biological aspects of the electrochemical or redox capacitance are discussed theoretically in the context of current knowledge with regard to structure and physiological activity of microbial Geobacter biofilms.Fil: Bueno, Paulo R.. Universidade Estadual Paulista. Institute of Chemistry; BrasilFil: Schrott, Germán David. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación En Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; ArgentinaFil: Bonanni, P. Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación En Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; ArgentinaFil: Simison, Silvia Noemi. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación En Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; ArgentinaFil: Busalmen, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación En Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; Argentin

Human Fallopian Tube Mesenchymal Stromal Cells Enhance Bone Regeneration in a Xenotransplanted Model

We have recently reported that human fallopian tubes, which are discarded during surgical procedures of women submitted to sterilization or hysterectomies, are a rich source of human fallopian tube mesenchymal stromal cells (htMSCs). It has been previously shown that human mesenchymal stromal cells may be useful in enhancing the speed of bone regeneration. This prompted us to investigate whether htMSCs might be useful for the treatment of osteoporosis or other bone diseases, since they present a pronounced capacity for osteogenic differentiation in vitro. Based on this prior knowledge, our aim was to evaluate, in vivo, the osteogenic capacity of htMSCs to regenerate bone through an already described xenotransplantation model: nonimmunosuppressed (NIS) rats with cranial defects. htMSCs were obtained from five 30–50 years old healthy women and characterized by flow cytometry and for their multipotenciality in vitro capacity (osteogenic, chondrogenic and adipogenic differentiations). Two symmetric full-thickness cranial defects on each parietal region of seven NIS rats were performed. The left side (LS) of six animals was covered with CellCeram (Scaffdex)—a bioabsorbable ceramic composite scaffold that contains 60% hydroxyapatite and 40% β-tricalciumphosphate—only, and the right side (RS) with the CellCeram and htMSCs (106 cells/scaffold). The animals were euthanized at 30, 60 and 90 days postoperatively and cranial tissue samples were taken for histological analysis. After 90 days we observed neobone formation in both sides. However, in animals euthanized 30 and 60 days after the procedure, a mature bone was observed only on the side with htMSCs. PCR and immunofluorescence analysis confirmed the presence of human DNA and thus that human cells were not rejected, which further supports the imunomodulatory property of htMSCs. In conclusion, htMSCs can be used successfully to enhance bone regeneration in vivo, opening a new field for future treatments of osteoporosis and bone reconstruction

AVALIAÇÃO DE FILÉS DE TILÁPIA, COMERCIALIZADOS EM DIFERENTES TIPOS DE EMBALAGEM

O pescado apresenta expressivo valor nutricional representando uma das mais importantes fontes proteicas de alto valor biológico entre as proteínas de origem animal. Por ser um produto de alta perecibilidade, a qualidade no seu manuseio, preparo e comercialização são essenciais para garantir a qualidade e segurança do produto. Assim, avaliar-se diferentes formas de embalagem/apresentação do produto são importantes para a identificação de melhores práticas para a comercialização de pescados. O objetivo do presente estudo foi avaliar quatro métodos diferentes de manutenção de filés de tilápia no processo de comercialização em temperatura resfriada, por meio da monitoria da vida de prateleira através de análises sensoriais, físico-químicas e histológicas. Foram avaliados os seguintes tratamentos: T1 – filés mantidos em caixa isotérmica com gelo; T2 – filés mantidos em bandejas isotérmicas coberto com filme de PVC; T3 – filés mantidos em embalagem plástica à vácuo; T4 – filés mantidos em embalagem plástica em atmosfera modificada. A temperatura, pH, avaliação sensorial e histológica dos filés foram avaliados diariamente até os filés estarem inadequados para consumo. Dentre os tratamentos avaliados tanto com a embalagem à vácuo quanto em com a atmosfera modificada foi possível estender a vida de prateleira do produto além do que é recomendado de forma geral no comércio varejista. Assim, em continuidade a este estudo seria de grande interesse avaliar-se os custos dessas embalagens em relação à perda por produtos descartados diariamente, bem como o impacto ambiental da introdução do uso dessas embalagens no comércio varejista

The brazilian Amaryllidaceae as a source of acetylcholinesterase inhibitory alkaloids

Nine Brazilian Amaryllidaceae species were studied for their alkaloid composition and acetylcholinesterase (AChE) inhibitory activity via GC-MS and a modified Ellman assay, respectively. A total of thirty-six alkaloids were identified in these plants, of which Hippeastrum papilio and H. glau-cescens exhibited the highest galanthamine content and the best IC50 values against AChE. Furthermore, Hippeastrum vittatum and Rhodophiala bifida also showed notable AChE inhibitory effects. X-ray crys-tallographic data for four galanthamine-type com-pounds revealed significant differences in the orientation of theN-methyl group, which are shown to be related to AChE inhibition