30 resultados para Presentation of awards


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Perceiving a possible predator may promote physiological changes to support prey 'fight or flight'. In this case, an increase in ventilatory frequency (VF) may be expected, because this is a way to improve oxygen uptake for escape tasks. Therefore, changes in VF may be used as a behavioral tool to evaluate visual recognition of a predator threat. Thus, we tested the effects of predator visual exposure on VF in the fish Nile tilapia, Oreochromis niloticus. For this, we measured tilapia VF before and after the presentation of three stimuli: an aquarium with a harmless fish or a predator or water (control). Nile tilapia VF increased significantly in the group visually exposed to a predator compared with the other two, which were similar to each other. Hence, we conclude that Nile tilapia may recognize an allopatric predator; consequently VF is an effective tool to indicate visual recognition of predator threat in fish. (C) 2002 Elsevier B.V. B.V. All rights reserved.

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Following previously published observations that a conditioned response (CR) was lost more quickly by rainbow trout (Oncorhynchus mykiss) exhibiting a high responsiveness to stressors than by low responding individuals this study was designed to investigate the effects of exogenous cortisol on the retention of a CR in unselected rainbow trout. Fish held in isolation were conditioned over a 10-day period by pairing an innocuous signal (conditioned stimulus, CS: a water jet played on the surface of the tank water) with a mild stressor (unconditioned stimulus, US: 30 min of confinement). This resulted in a brief elevation of plasma cortisol levels (the CR) when the fish was exposed to the CS only. The effect of exogenous cortisol on the retention of the CR was evaluated by comparing the performance of fish that received cortisol-containing slow-release intraperitoneal implants, with fish receiving vehicle-only implants. Retention of the CR was assessed at intervals up to 35 days after conditioning ceased. The CR was considered to be evident when 30 min following presentation of the CS, mean plasma cortisol levels were significantly higher in conditioned than untrained fish. on day 1 both cortisol-implanted and vehicle-implanted conditioned fish exhibited a CR. However, from day 5 onwards the CR was observed only in the vehicle-implanted and conditioned group. This finding indicates that administration of cortisol accelerated the extinction of the CR in the cortisol-implanted fish, suggesting that elevated plasma cortisol levels can impair memory processes in rainbow trout. (c) 2006 Elsevier B.V. All rights reserved.

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This study tested the adequacy of feeding as an unconditioned stimulus (US) to condition an endocrine response (plasma cortisol increase) in the cichlid fish Nile tilapia (Oreochromis niloticus). In a first study, conditioning was confirmed in grouped fish in the only experiment using single-held Nile tilapia. In this test a conditioned stimulus (CS - aeration off) was associated with a stressor (air emersion for 2 min - US). We then assessed whether several events of paired CS-US resulted in a conditioned endocrine response (CR), in this case an increase in plasma cortisol after presentation of the CS only. Before testing feeding as US, the postprandial or social holding condition for feeding effects on cortisol levels was tested. Nile tilapia showed increased cortisol after feeding associated to social context (grouped fish), but not to food only (single-held fish). In a third study, feeding was tested as US in an experiment similar to the first study but an increase in feeding-induced cortisol could not be conditioned. The absence of CR suggests that the stressor affects acquisition of this response, which may be a consequence of stimulus intensity or biological relevance. This study expands the recently reported Pavlovian conditioning paradigm for endocrine response in fish. (C) 2007 Elsevier B.V. All rights reserved.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Two lines of rainbow trout (Oncorhynchus mykiss) that exhibit divergent endocrine responsiveness to stressors also display disparate behavioral traits. To investigate whether the high-responding (HR) and low-responding (LR) fish also differ in cognitive function, the rate of extinction of a conditioned response was compared between the two lines. Groups of HR and LR fish were exposed to a paired conditioned stimulus (CS- water off) and unconditioned stimulus (US; confinement stressor). After exposure to 18 CS-US pairings, at least 70% of individuals of both lines acquired a conditioned response (CR) manifested as an elevation of blood cortisol levels on presentation of the CS only. Post-conditioning, the fish were tested by presentation of the CS at weekly intervals, for 4 weeks, with no further reinforcement, and the extinction of the CR in the two lines was compared. The decline in mean plasma cortisol levels after exposure to the CS over successive tests suggested that the CR was retained for a shorter period among the HR (<14 days) than LR fish (<21 days). The frequency of individuals within each line whose plasma cortisol levels indicated a stress response when exposed to the CS was significantly greater among the LR than HR fish at 14 and 21 days with no HR fish falling into this category at 21 days. At 28 days post-conditioning, there were no HR fish and only three LR fish were categorized as stressed. These results suggest that there are differences in cognitive function between the two lines. Possible mechanisms underlying these differences are discussed. (C) 2004 Elsevier B.V. All rights reserved.

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Heat-shock proteins (HSPs) are currently one of the most promising targets for the development of immunotherapy against tumours and autoimmune disorders. This protein family has the capacity to activate or modulate the function of different immune system cells. They induce the activation of monocytes, macrophages and dendritic cells, and contribute to cross-priming, an important mechanism of presentation of exogenous antigen in the context of MHC class I molecules, These various immunological properties of HSP have encouraged their use in several clinical trials. Nevertheless, an important issue regarding these proteins is whether the high homology among HSPs across different species may trigger the breakdown of immune tolerance and induce autoimmune diseases. We have developed a DNA vaccine codifying the Mycobacterium leprae Hsp65 (DNAhsp65), which showed to be highly immunogenic and protective against experimental tuberculosis. Here, we address the question of whether DNAhsp65 immunization could induce pathological autoimmunity in mice. Our results show that DNAhsp65 vaccination induced antibodies that can recognize the human Hsp60 but did not induce harmful effects in 16 different organs analysed by histopathology up to 210 days after vaccination. We also showed that anti-DNA antibodies were not elicited after DNA vaccination. The results are important for the development of both HSP and DNA-based immunomodulatory agents.

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The main objective of this paper is to make a prospective analysis about the tendencies of the world wide strategies of commercial vehicles development, in relation of the current local and international scenery. It has been done a research by using the Delphi method, which consists into regulate, systematically, the presentation of questions about a specified problem to a group of specialists. In order to guarantee more representative data, it has been adopted three distinct groups: academics, OEMs managers and Tier 1 suppliers managers. The results showed that the three mentioned groups have similar opinion about the necessity of having a product development in the subsidiaries companies; also it has been pointed the necessity of having more taylor made vehicles, due to the intrinsic characteristics of this industry segment. Copyright © 2008 SAE International.

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Background. Oral lichen planus (OLP) is a chronic autoimmune disease characterized by multiple clinical presentations and a relatively high prevalence in the population. This retrospective patient record study investigated the profile of OLP in a group of Brazilian patients seen between 1989 and 2009. Findings. The clinical records were analyzed and data such as gender, age, race, clinical presentation of OLP, site affected, presence of symptoms and extraoral manifestations of the disease, smoking habit, and consumption of alcoholic beverages were obtained. Among the 1822 records of patients with oral mucosal lesions, OLP was identified in 6.03%. Of these, 76.36% were females, with a mean age of 54 years, and 85% were whites. The reticular form was the most frequent (81.81%). Extraoral lesions were observed in 32.72% of the patients and painful symptoms were reported by 50.90%. The cheek mucosa was the site most affected (92.72%) and multiple oral lesions were observed in 77.27% of the patients. Among patients with OLP, 18.18% reported a smoking habit and 29.09% the consumption of alcoholic beverages. Conclusions. This retrospective study showed a relatively high prevalence of OLP in the population studied, with a predominance of the disease among middle-aged white women and bilateral involvement of the cheek mucosa. Reticular lesions were the most frequent, followed by the erosive form which is mainly associated with painful symptoms. No relationship with tobacco or alcohol consumption was observed. © 2010 Almeida et al; licensee BioMed Central Ltd.

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The multi-relational Data Mining approach has emerged as alternative to the analysis of structured data, such as relational databases. Unlike traditional algorithms, the multi-relational proposals allow mining directly multiple tables, avoiding the costly join operations. In this paper, is presented a comparative study involving the traditional Patricia Mine algorithm and its corresponding multi-relational proposed, MR-Radix in order to evaluate the performance of two approaches for mining association rules are used for relational databases. This study presents two original contributions: the proposition of an algorithm multi-relational MR-Radix, which is efficient for use in relational databases, both in terms of execution time and in relation to memory usage and the presentation of the empirical approach multirelational advantage in performance over several tables, which avoids the costly join operations from multiple tables. © 2011 IEEE.

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INTRODUCTION Sinking skin flap syndrome or syndrome of the trephined is a rare complication after a large craniectomy, with a sunken skin above the bone defect with neurological symptoms such as severe headache, mental changes, focal deficits, or seizures. PRESENTATION OF CASE We report a case of 21 years old man with trefinated syndrome showing delayed dysautonomic changes. DISCUSSION Our patient had a large bone flap defect and a VP shunt that constitute risk factors to develop this syndrome. Also, there is reabsorption of bone tissue while it is placed in subcutaneous tissue. The principal symptoms of sinking skin flap syndrome are severe headache, mental changes, focal deficits, or seizures. Our patient presented with a delayed dysautonomic syndrome, with signs and symptoms very characteristics. Only few cases of this syndrome were related in literature and none were presented with dysautonomic syndrome. CONCLUSION We reported here a very uncommon case of sinking skill flap syndrome that causes a severe dysautonomic syndrome and worsening the patient condition. © 2013 The Authors.

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The strut-and-tie models are widely used in certain types of structural elements in reinforced concrete and in regions with complexity of the stress state, called regions D, where the distribution of deformations in the cross section is not linear. This paper introduces a numerical technique to determine the strut-and-tie models using a variant of the classical Evolutionary Structural Optimization, which is called Smooth Evolutionary Structural Optimization. The basic idea of this technique is to identify the numerical flow of stresses generated in the structure, setting out in more technical and rational members of strut-and-tie, and to quantify their value for future structural design. This paper presents an index performance based on the evolutionary topology optimization method for automatically generating optimal strut-and-tie models in reinforced concrete structures with stress constraints. In the proposed approach, the element with the lowest Von Mises stress is calculated for element removal, while a performance index is used to monitor the evolutionary optimization process. Thus, a comparative analysis of the strut-and-tie models for beams is proposed with the presentation of examples from the literature that demonstrates the efficiency of this formulation. © 2013 Elsevier Ltd.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Aim: To report a possible case of tremor fluoxetine-induced treated as Parkinson’s disease in an elderly female patient noncompliant with the pharmacotherapy, with uncontrolled hypertension and using fluoxetine to treat depression. Presentation of Case: Patient complained of sleepiness in the morning, agitation, anxiety, insomnia and mental confusion. Her greatest concern was about bilateral hand tremors which, in her view became, worse after biperiden was prescribed. Therefore, she stopped taking it. The initial medication was: omeprazole, losartan, biperiden, fluoxetine, atenolol + chlorthalidone, acetylsalicylic acid, atorvastatin and diazepam. Pharmacotherapeutic follow up was performed in order to check the necessity, safety and effectiveness of treatment. Discussion: During the analysis of pharmacotherapy, the patient showed uncontrolled blood pressure and had difficulty complying with the treatment. Thus, in view of the complaints expressed by the patient, our first hypothesis was a possible serotonin syndrome related to fluoxetine use. We proposed a change in the fluoxetine regime and discontinuation of biperiden. As tremors persisted, we suggested the replacement of fluoxetine by sertraline, since a possible tremor fluoxetine-induced could explain the complaint. This approach solved the drug-related problem identified. Conclusion: Tremors reported by the patient was identified as an iatrogenic event related to fluoxetine, which was solved by management of serotonin-reuptake inhibitors.

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Background: Most of the primary pulmonary tumors in dogs are malignant and from epithelial origin, being bronchioalveolar tumors more prevalent. Adenocarcinoma of clear cells, however, is a very rare pulmonary tumor and its origin is still unknown. It is related to several clinical abnormalities, including hypertrophic osteopathy, an unusual paraneoplastic syndrome characterized by a periosteal reaction along the shaft of long bones. Because of the unusual presentation of the pulmonary adenocarcinoma, the aim of this study was to describe the radiographic, histopathological, and immunohistochemical fi ndings of a dog affl icted with hypertrophic osteopathy secondary to an undifferentiated pulmonary adenocarcinoma of clear cells. Case: A 12-year-old, 45 kg, not castrated male Great Dane dog was presented with painful swelling of all four limbs and moderate respiratory distress. Radiographic examination and computed tomography of the limbs showed palisade-like periosteal bone proliferation involving radius, ulna, femur, patella, tibia, fi bula, tarsus, metacarpal, metatarsal and digits, suggesting hypertrophic osteopathy. Radiographic examination and computed tomography of the lungs also showed a round mass well delimited localized in the right diaphragmatic lobe. A lobectomy of the right diaphragmatic lobe and partial lobectomy of accessory lobe were performed. A poorly differentiated clear squamous cell carcinoma was diagnosed by histological examination. An immune-panel of CK5/CK6, CK7, p63 and TTF-1 was used for immunophenotyping. Immunostaining was weakly positive for CK5/CK6 and negative to all others. Therefore, the diagnosis was poorly differentiated clear cell adenocarcinoma. The dog showed improvement in clinical signs seven days after surgery. One month postoperatively, radiographic examination of the limbs showed less intense periosteal reaction and initiation of bone remodeling. Discussion: Primary pulmonary tumors are considered very infrequent in small animals, but its true incidence rate is dif- fi cult to establish in animal populations. The histological origin of the tumor in the present case, as verifi ed in the literature, is not well established by histological analysis. In these situations, the immunohistochemistry panel may be useful. The modifi cation of the diagnosis between histological analysis and by immunohistochemistry, among other factors, might be due to transdifferentiation from one phenotype to another at various stages in the neoplastic process. The clear cell appearance observed in this case may be verifi ed in all types of carcinoma due to intracellular accumulation of glycogen, most of which is dissolved during the preparation of paraffi n sections. This uncommon neoplasm apparently did not infl uence the radiographic or tomographic fi ndings of the hypertrophic osteopathy in the present case. The frequency of metastases depends on the histological type of the tumor, being common in the pulmonary adenocarcinoma and usually to tracheobronchial lymph nodes and pulmonary parenchyma. Although in this case the imaging studies did not show metastases to other pulmonary lobes, the histological exams showed metastatic lesions that may be associated to the dog’s death after the surgery.