896 resultados para Non-muscle myosin II
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Aims: In the present work we investigated the in vitro effect of cis-4-decenoic acid, the pathognomonic metabolite of medium-chain acyl-CoA dehydrogenase deficiency, on various parameters of bioenergetic homeostasis in rat brain mitochondria. Main methods: Respiratory parameters determined by oxygen consumption were evaluated, as well as membrane potential, NAD(P)H content, swelling and cytochrome c release in mitochondrial preparations from rat brain, using glutamate plus malate or succinate as substrates. The activities of citric acid cycle enzymes were also assessed. Key findings: cis-4-decenoic acid markedly increased state 4 respiration, whereas state 3 respiration and the respiratory control ratio were decreased. The ADP/O ratio, the mitochondrial membrane potential, the matrix NAD(P)H levels and aconitase activity were also diminished by cis-4-decenoic acid. These data indicate that this fatty acid acts as an uncoupler of oxidative phosphorylation and as a metabolic inhibitor. cis-4-decenoic acid also provoked a marked mitochondrial swelling when either KCl or sucrose was used in the incubation medium and also induced cytochrome c release from mitochondria, suggesting a non-selective permeabilization of the inner mitochondria! membrane. Significance: It is therefore presumed that impairment of mitochondrial homeostasis provoked by cis-4-decenoic acid may be involved in the brain dysfunction observed in medium-chain acyl-CoA dehydrogenase deficient patients. (C) 2010 Elsevier Inc. All rights reserved.
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We have demonstrated previously that the complex bis[(2-oxindol-3-ylimino)-2-(2-aminoethyl)pyridine-N,N`]copper(II), named [Cu(isaepy)(2)], induces AMPK (AMP-activated protein kinase)-dependent/p53-mediated apoptosis in tumour cells by targeting mitochondria. In the present study, we found that p38(MAPK) (p38 mitogen-activated protein kinase) is the molecular link in the phosphorylation cascade connecting AMPK to p53. Transfection of SH-SY5Y cells with a dominant-negative mutant of AMPK resulted in a decrease in apoptosis and a significant reduction in phospho-active p38(MAPK) and p53. Similarly, reverse genetics of p38(MAPK) yielded a reduction in p53 and a decrease in the extent of apoptosis, confirming an exclusive hierarchy of activation that proceeds via AMPK/p38(MAPK)/p53. Fuel supplies counteracted [Cu(isaepy)(2)]-induced apoptosis and AMPK/p38(MAPK)/p53 activation, with glucose being the most effective, suggesting a role for energetic imbalance in [Cu(isaepy)(2)] toxicity. Co-administration of 3BrPA (3-bromopyruvate), a well-known inhibitor of glycolysis, and succinate dehydrogenase, enhanced apoptosis and AMPK/p38(MAPK)/p53 signalling pathway activation. Under these conditions, no toxic effect was observed in SOD (superoxide dismutase)-overexpressing SH-SY5Y cells or in PCNs (primary cortical neurons), which are, conversely, sensitized to the combined treatment with [Cu(isaepy)(2)] and 3BrPA only if grown in low-glucose medium or incubated with the glucose-6-phosphate dehydrogenase inhibitor dehydroepiandrosterone. Overall, the results suggest that NADPH deriving from the pentose phosphate pathway contributes to PCN resistance to [Cu(isaepy)(2)] toxicity and propose its employment in combination with 3BrPA as possible tool for cancer treatment.
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Two porous mixed valent diruthenium(II,III)-dicarboxylate compounds have been prepared and characterized by spectroscopic methods, X-ray diffraction and thermogravimetry. Crystalline solids of [Ru(2)(tere)(2)Cl] center dot 3.5H(2)O (tere=terephthalate) and [Ru(2)(adip)(2)Cl] center dot 1.5H(2)O (adip=adipate) consist of extended chains in which polymeric layers of multiply metal-metal bonded [Ru(2)](5+) cores are bridged by dicarboxylate ligands in paddlewheel type geometries. Units of [Ru(2)(dicarboxylate)(2)](n)(+) are linked by axial bridging chloride ions generating three-dimensional networks. The polymers loose non-bonded water molecules at low temperatures but do not undergo thermal decomposition below 280-300 degrees C. Both of compounds exhibit high BET surface areas, [Ru(2)(tere)(2)Cl]: 235 m(2) g(-1) and [Ru(2)(adip)(2)Cl]: 281 m(2) g(-1), and occlude similar numbers of mol of N(2) per mol of metal. The terephthalate ligand generated an organized structure with supermicropores (total pore size of 0.24 cm(3) g(-1)) while the adipate ligand led to a mesoporous structure (total pore sizes of 0.47 cm(3) g(-1)) for the corresponding diruthenium(II,III)-dicarboxylate polymers. (c) 2008 Elsevier B.V. All rights reserved.
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Social Entrepreneurship (SE) has attracted growing interest from a wide variety of actors over the last 30 years, especially due to a general agreement that it could be an important tool for tackling many of the world’s social ills. In the academic sphere, this growing interest did not translate into a matured field of study. Quite the opposite, a quick look at this literature makes it evident that: SE has been consistently subjected to numerous theoretical discussions and disagreements, especially over the definition of the concept of SE which is often based on a taken-for-granted notion of social change; it has been more systematically investigated in restricted contexts, often leaving aside so called developing/emerging countries like Brazil and especially lacking in-depth qualitative studies; SE literature lags behind SE practices and few studies focus on how SE actually occurs in a daily and bottom-up manner. In order to address such gaps, this thesis examines how social entrepreneurship practices accomplish social change in the context of Brazil. In this investigation I conducted an inductive practice-based, qualitative/ethnographic study in three Non-Governmental Organizations (NGOs) located in different cities in the Brazilian state of São Paulo. Data collection lasted from February 2014 until March 2015 and was mainly done through participant observations and through in-depth unstructured conversations with research participants. Secondary data and documents were also collected whenever available. The participants of this study included a variety of the studied organizations’ stakeholders: two founders, volunteers, employees, donors and beneficiaries. Observation data was kept in fieldnotes, conversations were recorded whenever possible and were later transcribed. Data was analyzed through an iterative thematic analysis. Through this I identified eight recurrent themes in the data: (1) structure; (2) relationship with other organizational actors (sub-themes: relationship with state, relationship with businesses and relationship with other NGOs); (3) beliefs, spirituality and moral authority; (4) social position of participants, (5) stakeholders’ mobilization and participation; (6) feelings; (7) social purpose; and (8) social change. These findings were later discussed under the lens of practice theory, and in this discussion I argue and show that, in the context studied: (a) even though SE embraces a wide variety of different social purposes, they are intertwined with a common notion of social change based on a general understanding and aspiration for social equality; (b) this social change is accomplished in a processual and ongoing manner as stakeholders from antagonistic social groups felt compelled to and participated in SE practices. In answering the proposed research question the contributions of this thesis are: (i) the elaboration a working definition for SE based on its relationship with social change; (ii) providing in-depth empirical evidence which accounts for and explains this relationship; (iii) characterizing SE in the Brazilian context and reflecting upon its transferability to other contexts. This thesis also makes a methodological contribution, for it demonstrates how thematic analysis can be used in practice-based studies.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Introduction: Chagas Disease is a serious public health problem, with 5 million infected individuals in Brazil. Of these, approximately 30% develop chronic Chagas cardiomyopathy (CCC), where the main symptoms are fatigue and dyspnea. Objective: To correlate maximal exercise capacity with pulmonary function, inspiratory muscle strength and quality of life in patients with CCC. Methodology: Twelve individuals suffering from CCC were evaluated (7 men), with a mean age of 54.91± 8.60 years and the following inclusion criteria: functional class II and III according to the New York Heart Association (NYHA); left ventricle ejection fraction below 45%; clinical stability (> 3 months); symptom duration > 1 year, body mass index (BMI) < 35Kg/m2 and non-smokers or ex-smokers with a history of smoking <10 packs/day. All subjects were submitted to spirometry, manometer testing, maximal cardiopulmonary exercise testing (CPX) and a quality of life questionnaire (Minnesota). Results: A negative correlation was observed between VO2máx and MLHFQ scores (r=-0.626; p=0.03) and a positive association with MIP (r=0.713; p=0.009). Positive correlations were also recorded between MIP and spirometric variables [FEV1(r=0.825;p=0.001 ), FVC(r=0.66;p=0.01 and FEF25-75%(r=0.639;p=0.02)]. Conclusion: The present study demonstrated that in patients with CCC: VO2MAX is directly related to inspiratory muscle strength and quality of life, while deteriorating lung function is directly associated with respiratory muscle weakness
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Partial neutralization of the myotoxic effect of Bothrops jararacussu venom (BV) and two of its myotoxins [bothropstoxin-I (BthTX-I), catalytically inactive, and II (BthTX-II), showing low PLA(2) activity], by the lyophilized aqueous extract of Tabernaemontana catharinensis (AE), was studied in rat isolated soleus muscle preparations (in vitro) and through i.m. injection in the gastrocnemius muscle (in vivo) by determination of creatine kinase (CK) activity and histopathological analysis. Incubation of soleus muscle for 1 h with BV or toxins (20 mug/ml) plus AE (400 mug/ml) added immediately after BV, BthTX-I or BthTX-II reduced CK levels by 53%, 37% and 56%, respectively. The myonecrotic effects of BV (20 mug/ml) upon soleus muscle was reduced 24%, 35% and 36% when AE (400 mug/ml) was added 1 h after BV and CK was evaluated 30 min, 1 and 2 h later, respectively. For BthTX-I these values were 46%, 48% and 47%, while for BthTX-II no inhibitory effect was detected. Histological analysis of soleus muscle after incubation with AE (400 mug/ml, I h) did not reveal any change in muscle fibers, but severe necrosis induced by -BV or toxins (20 mug/ml) was clearly in evidence, and decreased significantly when soleus muscle was protected by AE. This protection was also observed when AE was administered 1 h after BV or BthTX-I, but not after BthTX-II. AE did not inhibit the catalytic PLA(2), activity of BthTX-II or BV and did not change the PAGE pattern of BV, BthTX-I or BthTX-II. In vivo assays were performed in 100-g rats and maximal CK release was attained at a dose of 100 mug of BV, 3 h after injection. AE was not effective when injected 20 s after BV or toxins. However, injecting BV or toxins (100 mug), which were pre-incubated with AE (2 mg) caused an inhibition of 57%, 59% and 51%, respectively, with zero time pre-incubation, but was less effective with I h pre-incubation. This plant represents a potential source of promising myotoxin inhibitors. (C) 2004 Elsevier GmbH. All rights reserved.
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Este estudo objetivou caracterizar a resposta imune celular no sistema nervoso central (SNC) de eqüinos com infecção crônica experimental por Trypanosoma evansi. Para este propósito, foram utilizados os métodos histoquímicos (HE) e imunoistoquímicos do complexo avidina-biotina peroxidase (ABC). O fenótipo do infiltrado celular foi caracterizado com o auxílio de anticorpos anti - CD3, para linfócitos T e antiBLA36 para linfócitos B. Os macrófagos foram marcados com anticorpo antiantígenos da linhagem mielóide/histiócitos (Clone Mac387). A lesão no sistema nervoso central (SNC) dos eqüinos infectados com T. evansi foi caracterizada como meningoencefalite e meningomielite não supurativa. A gravidade das lesões variou em diferentes segmentos do SNC, refletindo distribuição irregular das alterações vasculares. A distribuição de células T e B e antígenos do complexo maior de histocompatibilidade classe II foram avaliados dentro do SNC de eqüinos cronicamente infectados com T. evansi. O infiltrado perivascular e meníngeo eram constituídos predominantemente por células T e B. Macrófagos foram raramente visualizados. T.evansi não foi identificado no parênquima do SNC dos eqüinos.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Background: In this study we evaluated the rehabilitation profile of Brazilian soccer players which underwent lower limb muscle lesions.Methods: This is a descriptive investigation. We evaluated 139 professional soccer players (1724 years old). We evaluated the following variables: muscle lesion diagnosis, symptoms, non steroidal anti-inflammatory used, physiotherapy treatment, which physiotherapy recourses was used if treated and train adaptation.Results: In great part of the athletes muscle lesion remained between 2 weeks and 1 month. Around 54% were diagnosed by a physician; the other part was diagnosed by a physical therapist. Non steroidal anti-inflammatory were prescribed by physicians in 42% of the cases; in 7% the physical therapist prescribed the medication while in 49% of the cases the masseur prescribed the drug. More than 1/4 of the athletes received physiotherapy treatement between 48 hours and 5 days. Isometric exercise therapy was applied in 15% of the cases. 63% were not accompanied by the physiotherapist on their return to the field. 48% received massages immediately after injury.Conclusion: We presented discrepancy between the recommended theory described by several researches and the practice. We indicate the necessity of recycling in a general context the rehabilitation of muscle injuries.
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The occurrence of Aeromonas spp., Vibrio cholerae, and Plesiomonas shigelloides in fresh water from various sources in Araraquara, State of São Paulo, Brazil was determined. Samples from ten distinct irrigation systems used in vegetable cultivation, from five distinct streams, from two reservoirs, from one artificial lake, and from three distinct springs were analyzed. All isolates were serotyped and tested for hemolysin, cytotoxin, heat-stable (ST) and heat-labile (LT) enterotoxins production; presence of plasmid; autoagglutination and drug resistance. V. cholerae isolates were also tested for cholera enterotoxin (CT) production, and Aeromonas isolates for suicide phenomenon. No P. shigelloides was found. V. cholerae non 01 was found in five irrigation water samples and in three stream samples. Aeromonas sp. were isolated in two samples of irrigation water, in three streams, and in one reservoir. All the V. cholerae and Aeromonas isolates were positive for P-hemolysin production, and all Aeromonas isolates were positive for suicide phenomenon; cytotoxic activities were observed in two Aeromonas strains. Cholera enterotoxin was not found in eight V. cholerae non-01 isolates tested by the Y-1 mouse adrenal cell. All isolates were also negative for the other virulence markers. Ii cholelerae isolates were found to be sensitive to the majority of drugs tested, while Aeromonas strains presented multiple drug resistance..
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The treatment for abusive users of alcohol and other drugs suffered significant modifications until arriving to the psychosocial model that is used by Centro de Atenção Psicossocial CAPSad II Eastern Natal/RN (Psychosocial Support Center). That model appears starting from Brazilian sanitary and psychiatric reforms which are expressed in the principles and propositions of Sistema Único de Saúde SUS (Unique System of Health). The Psychiatric Reform meant a rupture with the mental hospital and hospital centered treatment pattern which was destined to the abusive users of alcohol and other drugs. The new proposal offers the universalization, democratization, regionalization and completeness of the actions in the field of mental health. It gathers a strictly interdisciplinary health staff. The purpose of this study is to evaluate the effectiveness of the treatment for abusive users of alcohol and other drugs offered by CAPSad II Eastern Natal/RN. The evaluation used, as priority, the qualitative social research through an evaluating study starting from the non-experimental model. The methodological process used different instruments of data collection: bibliographical and documental researches, systematic observations at CAPSad II Eastern Natal/RN and, mainly, the semistructured interviews (21) that were accomplished with the professionals, users and relatives of CAPSad II Eastern Natal/RN. The investigation showed the effectiveness of the service and, therefore, CAPSad II Eastern Natal/RN constitute itself as the main confronting strategy to the mental hospital and hospital centered treatment pattern of caring the abusive users of alcohol and other drugs
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In this work, we use a nonlinear control based on Optimal Linear Control. We used as mathematical model a Duffing equation to model a supporting structure for an unbalanced rotating machine with limited power (non-ideal motor). Numerical simulations are performed for a set control parameter (depending on the voltage of the motor, that is, in the static and dynamic characteristic of the motor) The interaction of the non-ideal excitation with the structure may lead to the occurrence of interesting phenomena during the forward passage through the several resonance states of the system. Chaotic behavior is obtained for values of the parameters. Then, the proposed control strategy is applied in order to regulate the chaotic behavior, in order to obtain a periodic orbit and to decrease its amplitude. Both methodologies were used in complete agreement between them. The purpose of the paper is to give suggestions and recommendations to designers and engineers on how to drive this kind of system through resonance.
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This thesis presents ⇡SOD-M (Policy-based Service Oriented Development Methodology), a methodology for modeling reliable service-based applications using policies. It proposes a model driven method with: (i) a set of meta-models for representing non-functional constraints associated to service-based applications, starting from an use case model until a service composition model; (ii) a platform providing guidelines for expressing the composition and the policies; (iii) model-to-model and model-to-text transformation rules for semi-automatizing the implementation of reliable service-based applications; and (iv) an environment that implements these meta-models and rules, and enables the application of ⇡SOD-M. This thesis also presents a classification and nomenclature for non-functional requirements for developing service-oriented applications. Our approach is intended to add value to the development of service-oriented applications that have quality requirements needs. This work uses concepts from the service-oriented development, non-functional requirements design and model-driven delevopment areas to propose a solution that minimizes the problem of reliable service modeling. Some examples are developed as proof of concepts
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Heart failure is associated with a skeletal muscle myopathy with cellular and extracellular alterations. The hypothesis of this investigation is that extracellular changes may be associated with enhanced mRNA expression and activity of matrix metalloproteinases (MMP). We examined MMP mRNA expression and MMP activity in Soleus (SOL), extensor digitorum longus (EDL), and diaphragm (DIA) muscles of young Wistar rat with monocrotaline-induced heart failure. Rats injected with saline served as age-matched controls. MMP2 and MMP9 mRNA contents were determined by RT-PCR and MMP activity by electrophoresis in gelatin-containing polyacrylamide gels in the presence of SDS under non-reducing conditions. Heart failure increased MMP9 mRNA expression and activity in SOL, EDL and DIA and MMP2 mRNA expression in DIA. These results suggest that MMP changes may contribute to the skeletal muscle myopathy during heart failure.