282 research outputs found

    Efeitos antiangiogĂȘnicos in vivo convalidam a atividade antineoplĂĄsica potencial do metiljasmonato

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    Molecular plant components have long been aimed at the angiogenesis and anti-angiogenesis pathways, and have been tested as sources for antineoplasic drugs with promising success. The present work deals with the anti-angiogenic effects of Methyl Jasmonate. Jasmonate derivatives were demonstrated to selectively damage the mitochondria of cancer cells. In vitro, 1-10 mM Methyl Jasmonate induced the cell death of the human umbilical vein endothelial cells (HUVEC) and the Murine melanoma cells (B16F10), while micromolar concentrations were ineffective. In vivo, comparable concentrations were toxic and reduced the vessel density of the Chorioallantoic Membrane of the Chicken Embryo (CAM). However, 1-10 ”M concentrations produced a complex effect. There was increased capillary budding, but the new vessels were leakier and less organised than corresponding controls. It is suggested that not only direct toxicity, but also the drug effects upon angiogenesis are relevant to the antineoplasic effects of Methyl Jasmonate.MolĂ©culas de origem vegetal sĂŁo, hĂĄ muito, conhecidas como substĂąncias ativas sobre as vias de angiogĂȘnese e antiangiogĂȘnese e foram testadas como fonte de drogas antineoplĂĄsicas com sucesso promissor. Este trabalho trata dos efeitos antiangiogĂȘnicos do Metiljasmonato, um protĂłtipo da famĂ­lia dos derivados do ĂĄcido jasmĂŽnico, que danificam seletivamente a mitocĂŽndria de cĂ©lulas neoplĂĄsicas. In vitro, metiljasmonato 1-10 mM promoveu a morte celular de cĂ©lulas endoteliais humanas de cordĂŁo umbilical (HUVEC) e de melanoma murino (B16F10); concentraçÔes micromolares foram inĂłcuas. In vivo, concentraçÔes equivalentes foram tĂłxicas e reduziram a densidade de vasos em membranas corioalantoicas de embriĂŁo de galinha (CAM). Entretanto, concentraçÔes entre 1-10 ”M produziram um efeito complexo. Ocorreu aumento no brotamento capilar, mas os novos vasos apresentaram-se frĂĄgeis e menos organizados que os controles correspondentes. Sugere-se que, alĂ©m da toxicidade direta contra as cĂ©lulas tumorais, a ação do metiljasmonato sobre a angiogĂȘnese seja relevante para seu efeito antineoplĂĄsico

    Plasma glucose regulation and insulin secretion in hypertriglyceridemic mice

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    In this study, we examined glucose homeostasis and insulin secretion in transgenic mice overexpressing the human apolipoprotein CIII gene (apo CIII tg). These mice have elevated plasma levels of triglycerides, FFA and cholesterol compared to control mice. The body weight, plasma glucose, and insulin levels, glucose disappearance rates, areas under the ipGTT curve for adult (4-8 mo. old) and aged (20-24 mo. old) apo CIII tg mice and the determination of insulin during the ipGTT were riot different from those of control mice. However, an additional elevation of plasma FFA by treatment with heparin for 2-4h impaired the ipGTT responses in apo CIII tg mice compared to saline-treated mice. The glucose disappearance rate in heparin-treated transgenic mice was slightly lower than in heparin-treated controls. Glucose (22.2 mmol/l) stimulated insulin secretion in isolated islets to the same extent in saline-treated control and apo CIII tg mice. in islets from heparin-treated apo CIII tg mice, the insulin secretion at 2.8 and 22.2 mmol glucose/l was lower than in heparin-treated control mice. In conclusion, hypertriglyceridemia per se or a mild elevation in FFA did not affect insulin secretion or insulin resistance in adult or aged apo CIII tg mice. Nonetheless, an additional elevation of FFA induced by heparin in hypertriglyceridemic mice impaired the ipGTT by reducing insulin secretion.341212

    Aves que nidificam em cavidades na Reserva Natural Salto Morato - Guaraqueçaba (PR) /

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    Orientador : James Joseph RoperDissertaçăo (mestrado) - Universidade Federal do Paraná, Setor de Cięncias Biológicas, Programa de Pós-Graduaçăo em Ecologia e Conservaçao. Defesa: Curitiba, 2007Inclui bibliografi

    Design-time formal verification for smart environments: an exploratory perspective

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    Smart environments (SmE) are richly integrated with multiple heterogeneous devices; they perform the operations in intelligent manner by considering the context and actions/behaviors of the users. Their major objective is to enable the environment to provide ease and comfort to the users. The reliance on these systems demands consistent behavior. The versatility of devices, user behavior and intricacy of communication complicate the modeling and verification of SmE's reliable behavior. Of the many available modeling and verification techniques, formal methods appear to be the most promising. Due to a large variety of implementation scenarios and support for conditional behavior/processing, the concept of SmE is applicable to diverse areas which calls for focused research. As a result, a number of modeling and verification techniques have been made available for designers. This paper explores and puts into perspective the modeling and verification techniques based on an extended literature survey. These techniques mainly focus on some specific aspects, with a few overlapping scenarios (such as user interaction, devices interaction and control, context awareness, etc.), which were of the interest to the researchers based on their specialized competencies. The techniques are categorized on the basis of various factors and formalisms considered for the modeling and verification and later analyzed. The results show that no surveyed technique maintains a holistic perspective; each technique is used for the modeling and verification of specific SmE aspects. The results further help the designers select appropriate modeling and verification techniques under given requirements and stress for more R&D effort into SmE modeling and verification researc

    Lichen rehydration in heavy metal polluted environments: Pb modulates the oxidative response of both Ramalina farinacea thalli and its isolated microalgae

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    Lichens are adapted to desiccation/rehydration and accumulate heavy metals, which induce ROS especially from the photobiont photosynthetic pigments. Although their mechanisms of abiotic stress tolerance are still to be unravelled, they seem related to symbionts' reciprocal upregulation of antioxidant systems. With the aim to study the effect of Pb on oxidative status during rehydration, the kinetics of intracellular ROS, lipid peroxidation and chlorophyll autofluorescence of whole Ramalina farinacea thalli and its isolated microalgae (Trebouxia TR1 and T. TR9) was recorded. A genetic characterization of the microalgae present in the thalli used was also carried out in order to assess possible correlations among the relative abundance of each phycobiont, their individual physiological responses and that of the entire thallus. Unexpectedly, Pb decreased ROS and lipid peroxidation in thalli and its phycobionts, associated with a lower chlorophyll autofluorescence. Each phycobiont showed a particular pattern, but the oxidative response of the thallus paralleled the TR1's, agreeing with the genetic identification of this strain as the predominant phycobiont. We conclude that: (1) the lichen oxidative behaviour seems to be modulated by the predominant phycobiont and (2) Pb evokes in R. farinacea and its phycobionts strong mechanisms to neutralize its own oxidant effects along with those of rehydration

    Folliculin mutations are not associated with severe COPD

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    <p>Abstract</p> <p>Background</p> <p>Rare loss-of-function folliculin (<it>FLCN</it>) mutations are the genetic cause of Birt-Hogg-Dubé syndrome, a monogenic disorder characterized by spontaneous pneumothorax, fibrofolliculomas, and kidney tumors. Loss-of-function folliculin mutations have also been described in pedigrees with familial spontaneous pneumothorax. Because the majority of patients with folliculin mutations have radiographic evidence of pulmonary cysts, folliculin has been hypothesized to contribute to the development of emphysema.</p> <p>To determine whether folliculin sequence variants are risk factors for severe COPD, we genotyped seven previously reported Birt-Hogg-Dubé or familial spontaneous pneumothorax associated folliculin mutations in 152 severe COPD probands participating in the Boston Early-Onset COPD Study. We performed bidirectional resequencing of all 14 folliculin exons in a subset of 41 probands and subsequently genotyped four identified variants in an independent sample of345 COPD subjects from the National Emphysema Treatment Trial (cases) and 420 male smokers with normal lung function from the Normative Aging Study (controls).</p> <p>Results</p> <p>None of the seven previously reported Birt-Hogg-Dubé or familial spontaneous pneumothorax mutations were observed in the 152 severe, early-onset COPD probands. Exon resequencing identified 31 variants, including two non-synonymous polymorphisms and two common non-coding polymorphisms. No significant association was observed for any of these four variants with presence of COPD or emphysema-related phenotypes.</p> <p>Conclusion</p> <p>Genetic variation in folliculin does not appear to be a major risk factor for severe COPD. These data suggest that familial spontaneous pneumothorax and COPD have distinct genetic causes, despite some overlap in radiographic characteristics.</p

    Evaluation of Cellular Phenotypes Implicated in Immunopathogenesis and Monitoring Immune Reconstitution Inflammatory Syndrome in HIV/Leprosy Cases

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    BACKGROUND: It is now evident that HAART-associated immunological improvement often leads to a variety of new clinical manifestations, collectively termed immune reconstitution inflammatory syndrome, or IRIS. This phenomenon has already been described in cases of HIV coinfection with Mycobacterium leprae, most of them belonging to the tuberculoid spectrum of leprosy disease, as observed in leprosy reversal reaction (RR). However, the events related to the pathogenesis of this association need to be clarified. This study investigated the immunological profile of HIV/leprosy patients, with special attention to the cellular activation status, to better understand the mechanisms related to IRIS/RR immunopathogenesis, identifying any potential biomarkers for IRIS/RR intercurrence. METHODS/PRINCIPAL FINDINGS: Eighty-five individuals were assessed in this study: HIV/leprosy and HIV-monoinfected patients, grouped according to HIV-viral load levels, leprosy patients without HIV coinfection, and healthy controls. Phenotypes were evaluated by flow cytometry for T cell subsets and immune differentiation/activation markers. As expected, absolute counts of the CD4+ and CD8+ T cells from the HIV-infected individuals changed in relation to those of the leprosy patients and controls. However, there were no significant differences among the groups, whether in the expression of cellular differentiation phenotypes or cellular activation, as reflected by the expression of CD38 and HLA-DR. Six HIV/leprosy patients identified as IRIS/RR were analyzed during IRIS/RR episodes and after prednisone treatment. These patients presented high cellular activation levels regarding the expression of CD38 in CD8+ cells T during IRIS/RR (median: 77,15%), dropping significantly (p<0,05) during post-IRIS/RR moments (median: 29,7%). Furthermore, an increase of cellular activation seems to occur prior to IRIS/RR. CONCLUSION/SIGNIFICANCE: These data suggest CD38 expression in CD8+ T cells interesting tool identifying HIV/leprosy individuals at risk for IRIS/RR. So, a comparative investigation to leprosy patients at RR should be conducted
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