11 research outputs found

    Higher Expression of CCL2, CCL4, CCL5, CCL21, and CXCL8 Chemokines in the Skin Associated with Parasite Density in Canine Visceral Leishmaniasis

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    Several previous studies correlated immunopathological aspects of canine visceral leishmaniasis (CVL) with tissue parasite load and/or the clinical status of the disease. Recently, different aspects of the immune response in Leishmania-infected dogs have been studied, particularly the profile of cytokines in distinct compartments. However, the role of chemokines in disease progression or parasite burdens of the visceralising species represents an important approach for understanding immunopathology in CVL. We found an increase in inflammatory infiltrate, which was mainly composed of mononuclear cells, in the skin of animals presenting severe forms of CVL and high parasite density. Our data also demonstrated that enhanced parasite density is positively correlated with the expression of CCL2, CCL4, CCL5, CCL21, and CXCL8. In contrast, there was a negative correlation between parasite density and CCL24 expression. These findings represent an advance in the knowledge of the involvement of skin inflammatory infiltrates in CVL and the systemic consequences and may contribute to developing a rational strategy for the design of new and more efficient prophylactic tools and immunological therapies against CVL

    Terrestrial behavior in titi monkeys (Callicebus, Cheracebus, and Plecturocebus) : potential correlates, patterns, and differences between genera

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    For arboreal primates, ground use may increase dispersal opportunities, tolerance to habitat change, access to ground-based resources, and resilience to human disturbances, and so has conservation implications. We collated published and unpublished data from 86 studies across 65 localities to assess titi monkey (Callicebinae) terrestriality. We examined whether the frequency of terrestrial activity correlated with study duration (a proxy for sampling effort), rainfall level (a proxy for food availability seasonality), and forest height (a proxy for vertical niche dimension). Terrestrial activity was recorded frequently for Callicebus and Plecturocebus spp., but rarely for Cheracebus spp. Terrestrial resting, anti-predator behavior, geophagy, and playing frequencies in Callicebus and Plecturocebus spp., but feeding and moving differed. Callicebus spp. often ate or searched for new leaves terrestrially. Plecturocebus spp. descended primarily to ingest terrestrial invertebrates and soil. Study duration correlated positively and rainfall level negatively with terrestrial activity. Though differences in sampling effort and methods limited comparisons and interpretation, overall, titi monkeys commonly engaged in a variety of terrestrial activities. Terrestrial behavior in Callicebus and Plecturocebus capacities may bolster resistance to habitat fragmentation. However, it is uncertain if the low frequency of terrestriality recorded for Cheracebus spp. is a genus-specific trait associated with a more basal phylogenetic position, or because studies of this genus occurred in pristine habitats. Observations of terrestrial behavior increased with increasing sampling effort and decreasing food availability. Overall, we found a high frequency of terrestrial behavior in titi monkeys, unlike that observed in other pitheciids

    Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial

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    Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure <= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt

    Schistosoma mansoni encodes SMT3B and SMT3C molecules responsible for post-translational modification of cellular proteins

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    The sumoylation pathway is a post-translational modification of nuclear proteins widespread among several organisms. SMT3C is the main protein involved in this process and it is covalently conjugated to a diverse assortment of nuclear protein targets. To date, 3 SUMO paralogues (SMT3C, A/B) have been characterized in mammals and plants. In this work we characterized two SUMO related genes, named SMT3B and SMT3C throughout Schistosoma mansoni life cycle. The SmSMTB/C encodes for proteins sharing significant amino acid homology with SMT3. Phylogenetical analyses revealed that both SmSMT3B/C are distinct proteins. Additionally, SmSMT3B and C are expressed in cercariae, adult worms, eggs and schistosomula however SinSMT3C gene showed an expression level 7 to 9 fold higher than SmSMT3B in eggs, schistosomula and adult worms. The comparison between the SmSMT3C genomic and cDNA sequences established that the encoding sequence is interrupted by 3 introns of 70, 37 and 36 bp. Western Blot has shown SMT3 conjugates are present in nuclear and total protein fractions of adults and cercariae. Therefore our results suggest a functional sumoylation pathway, and the presence of two paralogues also suggests the specificity of substrates for SMT3 in S. mansoni. (c) 2008 Elsevier Ireland Ltd. All rights reserved

    Molecular cloning, sequencing, and expression analysis of presenilin cDNA from Schistosoma mansoni

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    Presenilins (PS) are integral membrane proteins involved, among other functions, in regulated intramembrane proteolysis. In this study, we report the identification and characterization of a complementary DNA from Schistosoma mansoni exhibiting a significant homology to human and nonvertebrate presinilins. S. mansoni contained a 1,485 bp open reading frame encoding a predicted protein of 494 amino acids. Alignment of predicted amino acid sequence of S. mansoni with PS (SmPS) from other species revealed up to 40% similarity shared among the investigated organisms. In addition, phylogenetic analyses demonstrated SmPS being closely related to its orthologues found in Schistosoma japonicum and Caenorhabditis elegans. Expression analysis of SmPS using quantitative real-time PCR revealed that the transcript is up-regulated in the egg stage. We hypothesize that the high level of SmPS in the S. mansoni embryo correlates to an important role during cellular signaling associated to larval development. To our knowledge, this study represents the first attempt to investigate the existence and abundance of PS from a helminth parasite.FAPESP Fundacao de Amparo a Pesquisa do Estado de Sao PauloCNPq Conselho Nacional de Desenvolvimento Cientifico e TecnologicoCAPES Coordenação de Aperfeiçoamento de Pessoal de Nível Superio

    Perfil audiométrico de trabalhadores do distrito industrial de Maracanaú - CE Audiometric profile of Maracanaú's industrial district workers

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    OBJETIVO: Estabelecer o perfil audiométrico de trabalhadores expostos ao ruído, acima do nível de ação (85 dB), em empresas do Distrito Industrial de Maracanaú, Ceará. MÉTODOS: Foi realizado um estudo descritivo de prevalência a partir da avaliação de dados de exames audiométricos, coletados de arquivos das empresas pesquisadas realizados no período de abril a outubro de 2006. Foram avaliados 5372 trabalhadores das 47 (52,80%) empresas que autorizaram a pesquisa e as variáveis analisadas foram: faixa etária, tempo total de exposição ao ruído, estado da acuidade auditiva, tipo de perda auditiva, lateralidade da perda auditiva e configuração audiométrica sugestiva de perda auditiva induzida por ruído nos trabalhadores e setor da atividade econômica e porte da empresa. RESULTADOS: Constatou-se que 19,00% da população estudada apresentaram alteração, predominando a perda auditiva sensório neural em 90,67% dos casos. Em 12,71% da população estudada observou-se quadro sugestivo de perda auditiva induzida por ruído (PAIR) e, em 71,77% da população portadora de perda auditiva sensório neural, há indícios de PAIR. Em relação à lateralidade da perda, 39,09% é unilateral, sendo 24,03% unilateral esquerda. CONCLUSÕES: Apesar dos resultados não representarem a prevalência total de perdas auditivas do Distrito, eles apontam para a necessidade não apenas de realização de audiometrias ocupacionais pontuais, mas também de monitoramento da audição dos trabalhadores de forma longitudinal, como parte de um programa de conservação auditiva.<br>PURPOSE: To establish the audiometric profile of workers exposed to noise above the action level (85 dB) in Maracanaú's Industrial District, Ceará (Brazil). METHODS: A descriptive study of prevalence was carried out through the evaluation of audiometric data gathered from the files of the researched companies between April and October of 2006. There were 5372 workers evaluated, from the 47 (52,80%) companies that authorized the study. The studied variables were: age range, total period of exposition to noise, auditory acuity status, type of hearing loss, hearing loss laterality and audiometric configuration suggestive of noise-induced hearing loss (NIHL) in workers, economic activity trade and size of the company. RESULTS: It was observed that 19% of the studied population presented alterations, with predominance of sensory neural hearing loss (SNHL) in 90.67% of the cases. In 12.71% of the population suggestive signs of noise-induced hearing loss (NIHL) were observed, and in 71.77% of the population with SNHL there were signs of NIHL. Regarding laterality of the hearing loss, 39.09% was unilateral, from which 24.03% was on the left ear. CONCLUSION: Although the results do not represent the total prevalence of hearing loss in the District, they point out to the necessity not only to perform occupational audiometry, but also to longitudinally monitor the hearing of these workers as part of a hearing conservation program

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

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    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
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