12 resultados para Berendsen, Herman J.

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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During sporulation, Bacillus subtilis redeploys the division protein FtsZ from midcell to the cell poles, ultimately generating an asymmetric septum. Here, we describe a sporulation-induced protein, RefZ, that facilitates the switch from a medial to a polar FtsZ ring placement. The artificial expression of RefZ during vegetative growth converts FtsZ rings into FtsZ spirals, arcs, and foci, leading to filamentation and lysis. Mutations in FtsZ specifically suppress RefZ-dependent division inhibition, suggesting that RefZ may target FtsZ. During sporulation, cells lacking RefZ are delayed in polar FtsZ ring formation, spending more time in the medial and transition stages of FtsZ ring assembly. A RefZ-green fluorescent protein (GFP) fusion localizes in weak polar foci at the onset of sporulation and as a brighter midcell focus at the time of polar division. RefZ has a TetR DNA binding motif, and point mutations in the putative recognition helix disrupt focus formation and abrogate cell division inhibition. Finally, chromatin immunoprecipitation assays identified sites of RefZ enrichment in the origin region and near the terminus. Collectively, these data support a model in which RefZ helps promote the switch from medial to polar division and is guided by the organization of the chromosome. Models in which RefZ acts as an activator of FtsZ ring assembly near the cell poles or as an inhibitor of the transient medial ring at midcell are discussed.

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Introduction: Compulsive buying (CB) is currently classified as an impulse control disorder (ICD) not otherwise classified. Compulsive buying prevalence is estimated at around 5% of the general population. There is controversy about whether CB should be classified as an ICD, a subsyndromal bipolar disorder (BD), or an obsessive-compulsive disorder (OCD) akin to a hoarding syndrome. To further investigate the appropriate classification of CB, we compared patients with CB, BD, and OCD for impulsivity, affective instability, hoarding, and other OCD symptoms. Method: Eighty outpatients (24 CB, 21 BD, and 35 OCD) who were neither manic nor hypomanic were asked to fill out self-report questionnaires. Results: Compulsive buying patients scored significantly higher on all impulsivity measures and on acquisition but not on the hoarding subdimensions of clutter and "difficulty discarding." Patients with BD scored higher on the mania dimension from the Structured Clinical Interview for Mood Spectrum scale. Patients with OCD scored higher on obsessive-compulsive symptoms and, particularly, higher on the contamination/washing and checking dimensions from the Padua Inventory; however, they did not score higher on any hoarding dimension. A discriminant model built with these variables correctly classified patients with CB (79%), BD (71%), and OCD (77%). Conclusion: Patients with CB came out as impulsive acquirers, resembling ICD- rather than BD- or OCD-related disorders. Manic symptoms were distinctive of patients with BD. Hoarding symptoms other than acquisition were not particularly associated with any diagnostic group. (C) 2012 Elsevier Inc. All rights reserved.

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Dilthey claimed that first psychology and then hermeneutics played the foundational role for his philosophy of life, whose main practical goal is to develop a pedagogy or theory of education. Pedagogy needs help from h ethics to establish its ends, and from psychology to indicate it means. This paper intends to show the relationship between Dilthey's hermeneutics of life and his pedagogy. Dilthey's philosophy of life, in so far it adopts the hermeneutical procedure, engages in the understanding of or the search for the meaning of human socio-historical creations, by adopting a special type of relationship between parts and whole. It is exactly within this hermeneutical balance that we propose to extinguish any indication of a rupture, breach, or contradiction between the quest for universal principles of human behavior and :Dilthey's defense of the impossibility of constructing human moral tasks by means of universal principles. Dilthey began his ethics lectures at the University of Berlin in 1890. These lectures, published in 1958 by Herman Nohl in volume X of Dilthey's collected works, indicate the direction of the trajectory by which formative or social ethics are consolidated as a historical solution for reaching universal principles that can guide human purposes. This trajectory is a result of the distinctively human exercise of self-reflection, by means of which we can fulfill our destiny of manifesting and exteriorizing in time the immanent energy of the absolute spirit. We wish to show that it is possible that such a pedagogy can respect its universal task of orienting the historical development of the younger generation without directing this process by means of fixed and rigid aims.

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The European Position Paper on Rhinosinusitis and Nasal Polyps 2012 is the update of similar evidence based position papers published in 2005 and 2007. The document contains chapters on definitions and classification, we now also propose definitions for 'difficult to treat' rhinosinusitis, control of disease and better definitions for rhinosinusitis in children. More emphasis is placed on the diagnosis and treatment of acute rhinosinusitis. Throughout the document the terms chronic rhinosinusitis without nasal polyps (CRSsNP) and chronic rhinosinusitis with nasal polyps (CRSwNP) are used to further point out differences in pathophysiology and treatment of these two entities. There are extensive chapters on epidemiology and predisposing factors, inflammatory mechanisms, (differential) diagnosis of facial pain, genetics, cystic fibrosis, aspirin exacerbated respiratory disease, immunodeficiencies, allergic fungal rhinosinusitis and the relationship between the upper and lower airways. The chapters on paediatric acute and chronic rhinosinusitis are totally rewritten. Last but not least all available evidence for management of acute rhinosinusitis and chronic rhinosinusitis with or without nasal polyps in adults and children is analyzed and presented and management schemes based on the evidence are proposed. This executive summary for otorhinolaryngologists focuses on the most important changes and issues for otorhinolaryngologists.

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Molecular dynamics simulations of the model protein chignolin with explicit solvent were carried out, in order to analyze the influence of the Berendsen thermostat on the evolution and folding of the peptide. The dependence of the peptide behavior on temperature was tested with the commonly employed thermostat scheme consisting of one thermostat for the protein and another for the solvent. The thermostat coupling time of the protein was increased to infinity, when the protein is not in direct contact with the thermal bath, a situation known as minimally invasive thermostat. In agreement with other works, it was observed that only in the last situation the instantaneous temperature of the model protein obeys a canonical distribution. As for the folding studies, it was shown that, in the applications of the commonly utilized thermostat schemes, the systems are trapped in local minima regions from which it has difficulty escaping. With the minimally invasive thermostat the time that the protein needs to fold was reduced by two to three times. These results show that the obstacles to the evolution of the extended peptide to the folded structure can be overcome when the temperature of the peptide is not directly controlled.

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Stress is the most commonly reported precipitating factor for seizures in patients with epilepsy. Despite compelling anecdotal evidence for stress-induced seizures, animal models of the phenomena are sparse and possible mechanisms are unclear. Here, we tested the hypothesis that increased levels of the stress-associated hormone corticosterone ( CORT) would increase epileptiform activity and spontaneous seizure frequency in mice rendered epileptic following pilocarpine-induced status epilepticus. We monitored video-EEG activity in pilocarpine-treated mice 24/7 for a period of four or more weeks, during which animals were serially treated with CORT or vehicle. CORT increased the frequency and duration of epileptiform events within the first 24 hours of treatment, and this effect persisted for up to two weeks following termination of CORT injections. Interestingly, vehicle injection produced a transient spike in CORT levels - presumably due to the stress of injection - and a modest but significant increase in epileptiform activity. Neither CORT nor vehicle treatment significantly altered seizure frequency; although a small subset of animals did appear responsive. Taken together, our findings indicate that treatment of epileptic animals with exogenous CORT designed to mimic chronic stress can induce a persistent increase in interictal epileptiform activity.

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Objectives: Laparoscopic resection for benign liver disease has gained wide acceptance in recent years and hepatocellular adenoma (HA) seems to be an appropriate indication. This study aimed to discuss diagnosis and treatment strategies, and to assess the feasibility, safety and outcomes of pure laparoscopic liver resection (LLR) in a large series of patients with HA. Methods: Of 88 patients who underwent pure LLR, 31 were identified as having HA. Diagnosis was based on radiological evaluation and resections were performed for lesions measuring >5.0 cm. Results: The sample included 29 female and two male patients. Their mean age was 33.2 years. A total of 27 patients had a single lesion, one patient had two and one had four lesions. The two remaining patients had liver adenomatosis. Mean tumour size was 7.5 cm. Three right hepatectomies, 17 left lateral sectionectomies and 11 wedge resections or segmentectomies were performed. There was no need for blood transfusion or conversion to open surgery. Postoperative complications occurred in two patients. Mean hospital stay was 3.8 days. Conclusions: Hepatocellular adenoma should be regarded as an excellent indication for pure LLR. Pure LLR is safe and feasible and should be considered the standard of care for the treatment of HA when performed by surgeons with experience in liver and laparoscopic surgery.

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This work aimed to evaluate the efficiency of fungicides in controlling in vitro and in vivo the causal agents of anthracnose (Colletotrichum gloeosporioides and C. acutatum) and black spot (Guignardia psidii) and evaluate the effect of alternative products to control these diseases. Inhibition of mycelial growth of the pathogens was evaluated for ten fungicides at concentrations of 1, 10 and 100 mg L-1 of active ingredient in potato-dextrose-agar medium. The effectiveness of the fungicides azoxystrobin + difenoconazole, cyproconazole, pyraclostrobin, tebuconazole and tebuconazole + trifloxystrobin in controlling disease incidence and severity of anthracnose, through applications in the field, was measured in fruits collected at three stages of maturation, according to the skin color ( dark green, light green and yellowish green). In postharvest dipping of fruits, the products evaluated were citric acid, peracetic acid, salicylic acid, sodium bicarbonate, chlorine dioxide, Ecolife (R) and chitosan. The fungicides azoxystrobin + difenoconazole, pyraclostrobin, tebuconazole and trifloxystrobin + tebuconazole were highly effective in inhibiting the in vitro mycelial growth of G. psidii and moderately to highly effective in inhibiting C. acutatum and C. gloeosporioides. In field conditions, the fungicide azoxystrobin + difenoconazole was effective in controlling anthracnose and black spot in fruit at three maturity stage ( skin color yellowish green). The alternative products tested were ineffective in the curative control of anthracnose and early blight at postharvest of guava.

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CONTEXT: Liver metastases are a common event in the clinical outcome of patients with colorectal cancer and account for 2/3 of deaths from this disease. There is considerable controversy among the data in the literature regarding the results of surgical treatment and prognostic factors of survival, and no analysis have been done in a large cohort of patients in Brazil. OBJECTIVES: To characterize the results of surgical treatment of patients with colorectal liver metastases, and to establish prognostic factors of survival in a Brazilian population. METHOD: This was a retrospective study of patients undergoing liver resection for colorectal metastases in a tertiary cancer hospital from 1998 to 2009. We analyzed epidemiologic variables and the clinical characteristics of primary tumors, metastatic disease and its treatment, surgical procedures and follow-up, and survival results. Survival analyzes were done by the Kaplan-Meier method and the log-rank test was applied to determine the influence of variables on overall and disease-free survival. All variables associated with survival with P<0.20 in univariate analysis, were included in multivariate analysis using a Cox proportional hazard regression model. RESULTS: During the period analyzed, 209 procedures were performed on 170 patients. Postope-rative mortality in 90 days was 2.9% and 5-year overall survival was 64.9%. Its independent prognostic factors were the presence of extrahepatic disease at diagnosis of liver metastases, bilateral nodules and the occurrence of major complications after liver surgery. The estimated 5-year disease-free survival was 39.1% and its prognostic factors included R1 resection, extrahepatic disease, bilateral nodules, lymph node involvement in the primary tumor and primary tumors located in the rectum. CONCLUSION: Liver resection for colorectal metastases is safe and effective and the analysis of prognostic factors of survival in a large cohort of Brazilian patients showed similar results to those pointed in international series. The occurrence of major postoperative complications appears to be able to compromise overall survival and further investigation in needed in this topic.

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O Brasil é considerado o maior produtor de citros e o maior exportador de suco de laranja. Doenças de pós-colheita representam uma grande perda para a citricultura, sendo que para a exportação de frutos são rígidas as exigências com relação a isenção de resíduos químicos nos mesmos. Patógenos de importância em pós-colheita de citros incluem o Penicillium digitatum, agente causal do bolor-verde e o Colletotrichum gloeosporioides, agente causal da antracnose. Dada a importância econômica que representam estas doenças dos frutos cítricos, tanto em termos de comprometimento da qualidade e dificuldade de controle, a busca de alternativas adicionais que possam viabilizar a capacidade produtiva e garantir a obtenção de frutos com excelentes padrões de qualidade torna-se imprescindível. Portanto, estudou-se os efeitos dos extratos aquosos do flavedo de Citrus aurantifolia var. Tahiti, Lentinula edodes, Agaricus subrufescens (syn. Agaricus brasiliensis), albedo de Citrus sinensis var. Valência e do ácido jasmônico no controle póscolheita do bolor verde e da antracnose e na indução de resistência em frutos de laranjeira Valência (Citrus sinensis). Foi possível observar que o extrato aquoso do flavedo (C. aurantifolia) apresentou efeito inibitório sobre os patógenos, quando tratados em pós-colheita, em função da redução dos sintomas e esporulação. Porém, os extratos de albedo (C. sinensis), L. edodes, A. subrufescens e o ácido jasmônico não apresentaram efeitos sobre P. digitatum e C. gloeosporioides.

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Dilthey apontou primeiro a psicologia e depois a hermenêutica como tendo papel fundamental para sua filosofia da vida, cujo principal objetivo prático é desenvolver a pedagogia ou teoria geral da educação. A pedagogia necessita da ajuda da ética para estabelecer seus fins e da psicologia para indicar seus meios. Este texto tem por objetivo mostrar a relação entre hermenêutica da vida e pedagogia, para Dilthey. A filosofia da vida do autor, ao adotar procedimento hermenêutico, exercita a compreensão ou busca de significado das criações humanas histórico-sociais por um tipo especial de relação entre as partes e o todo. É justamente dentro desse balanço hermenêutico que propomos apagar qualquer vestígio de ruptura, brecha ou contradição entre a busca de princípios universais da ação humana e a impossibilidade de construção da tarefa humana moral, por meio de princípios universais. Só em 1890 Dilthey deu início às conhecidas conferências sobre ética, na Universidade de Berlim. Tais conferências, publicadas em 1958 por Herman Nohl, no volume X das Obras Completas, apontam as diretrizes do caminho que deverá consolidar a ética formativa ou social, enquanto solução histórica para o alcance de princípios universais de orientação para a conduta humana. Essa trajetória efetiva-se graças ao exercício distintivamente humano da autorreflexão. Por meio dela, é possível cumprir nosso destino de manifestar, exteriorizar no tempo a energia do espírito absoluto que nos é imanente. Diante desse panorama, este texto procura sublinhar como é possível que tal pedagogia possa respeitar sua tarefa universal de orientar historicamente o desenvolvimento das novas gerações, sem dirigir o processo por meio de fins rígida e fixamente estabelecidos.

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Este trabalho descreve a preparação e caracterização do híbrido celulose/fosfato de nióbio hidratado (Cel/NbOPO4.nH2O) utilizando como material de partida a celulose branqueada de bagaço de cana-de-açúcar e o nióbio metálico. O híbrido foi preparado por dois métodos: denominados métodos I e II. O método I consistiu na dissolução do nióbio metálico em solução de ácido fluorídrico/nítrico (100:10), com tempo de contato de 16 horas entre a celulose branqueada do bagaço de cana-de-açúcar e a solução ácida. Adicionou-se a essa solução ácido fosfórico para precipitação do material. O método II foi semelhante, com proporções diferentes da solução ácida fluorídrico/nítrico (160/100), sem tempo de contato da celulose com a solução ácida. Os métodos I e II utilizaram as seguintes proporções de cel/ Nb2O5.nH2O: (10:10);(10:6) e (10:2). Os materiais preparados pelos métodos I e II foram caracterizados por difração de raios X (DRX), termogravimetria (TG/DTG) e microscopia eletrônica de varredura (MEV). Observou-se aumento do índice do grau de cristalinidade e mudanças na morfologia dos materiais preparados.