948 resultados para Frontal disk


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O córtex pré-frontal medial (CPFM) é uma região límbica envolvida no controle da atividade autonômica e cardiovascular. Foi demonstrado que a inibição da região infra-límbica (IL) do CPFM reduziu as repostas comportamentais, neuroendócrinas e autônomas induzidas por estímulos aversivos. Entretanto, apesar das evidências de um importante papel do córtex IL na integração das respostas ao estresse, informações sobre os mecanismos neuroquímicos locais envolvidos no controle destas respostas ainda são escassos. Diante disso, o presente estudo teve o objetivo de investigar um possível envolvimento de mecanismos noradrenérgicos do córtex IL nas respostas autonômicas ao estresse por restrição agudo em ratos. Para tanto, nós investigamos, em grupos independentes de animais, o efeito da microinjeção bilateral no córtex IL de veículo (salina, 100nL), WB4101 (antagonista seletivo de adrenoceptores α1), RX821002 (antagonista seletivo de adrenoceptores α2) e propranolol (antagonista não-seletivo de adrenoceptores β, 10nmol/100nL), sobre as respostas de aumento da pressão arterial (PA) e frequência cardíaca (FC) e redução da temperatura cutânea da cauda induzidas pelo estresse por restrição agudo em ratos. A microinjeção bilateral de WB4101, RX821002 e propranolol no córtex IL não afetou os parâmetros basais de PA, FC e temperatura cutânea da cauda, o que indica uma ausência de influência na manutenção tônica do sistema cardiovascular. Entretanto, o bloqueio de adrenoceptores α1 no córtex IL diminuiu a resposta taquicárdica induzida pelo estresse por restrição, sem afetar as respostas pressora e de redução da temperatura cutânea da cauda. O bloqueio de adrenoceptores α2 no córtex IL reduziu todos os parâmetros analisados e o bloqueio de adrenoceptores β no córtex IL atenuou a resposta de redução da temperatura cutânea induzida pelo estresse por restrição. As respostas de elevação da ...

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Medo e a ansiedade são emoções que têm origem nas reações de defesa que os animais exibem diante de ameaças que podem comprometer sua integridade física ou a própria sobrevivência, tais como confrontos com o predador ou com animais da mesma espécie. Em se tratando da espécie humana, estas respostas defensivas eliciadas representariam a ocorrência de transtornos de ansiedade e, a busca por sua compreensão, resultou no desenvolvimento de modelos animais de ansiedade, dentre os quais se destaca o labirinto em cruz elevado (LCE) que é baseado na aversão natural de roedores a espaços abertos. Com relação aos substratos neurais envolvidos nestas manifestações, cabe destacar a matéria cinzenta periaquedutal bem como estruturas prosencefálicas, como o córtex pré-frontal (CPFm), uma estrutura límbica que tem sido frequentemente descrita como relevante na neurobiologia da ansiedade. O óxido nítrico (NO) tem sido investigado em diferentes estruturas cerebrais de roedores nas quais foram evidenciadas respostas pró-aversivas. Sendo o CPFm uma estrutura que contém neurônios nitrérgicos, este estudo teve o objetivo de investigar o efeito da facilitação nitrérgica através da injeção intra-CPFm de um doador de NO, o NOC-9 [6-(Hidroxi-1-metil-2-nitrosohidrazino)-N-metil-1-hexanamina], sobre o comportamento de camundongos expostos ao labirinto em cruz elevado (LCE). Métodos e Resultados: Camundongos Suíços machos (25-35g, n = 53) receberam implante de cânula guia no CPFm. Cinco dias após, os animais receberam microinjeção de veículo ou NOC-9 nas doses de (1,875 nmol; 18,75 nmol; 37,5 nmol ou 75nmol) e, após cinco minutos, foram expostos... (Resumo completo, clicar acesso eletrônico abaixo)

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Pós-graduação em Engenharia Mecânica - FEG

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This study evaluated postoperative results of 8 cases of frontal sinus fractures treated by frontal sinus obliteration with autogenous bone from the anterior iliac crest. Patients and methods: The medical charts of patients sequentially treated for frontal sinus fractures by obliteration with autogenous cancellous iliac crest bone in the Oral and Maxillofacial Surgery Division of this institution were reviewed. From those, eight had complete records and adequately described long-term follow-up. All were operated by the same surgical team. Those patients were recalled and independently evaluated by 2 examiners. Radiographs and/or CT scans were available for this evaluation. Associated fractures and complications were noted. The average postoperative follow-up was 7 years, ranging from 3 to 16 years. The main complication was infection. Four patients (50%) had uneventful long-term follow-ups and four (50%) experienced complications requiring reoperation. Based on the studied sample studied the authors conclude that the obliteration with autogenous bone presented a high percentage of complications in this series.

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This study evaluated postoperative results of 8 cases of frontal sinus fractures treated by frontal sinus obliteration with autogenous bone from the anterior iliac crest.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Craniofacial trauma can lead to several complications. The combined fractures of anterior and posterior walls of the frontal bone are almost always followed by lesions in nasofrontal orifices and disruption of nasofrontal ostia or ducts, a significant factor for the development of early and late complications after sinus fractures. This article reports a case of trauma patient, who underwent neurological evaluation and at first showed good general condition. Computed tomography noted fracture of the anterior and posterior walls of the frontal sinus and small foci of pneumocephalus in the cerebral cortex. The patient was monitored periodically and 9 days after trauma showed increased areas of pneumocephalus in prefrontal cortex, cerebrospinal fluid draining, and large dura mater lesion, with signs of necrosis and inflammation (meningitis). The necrotic tissues were removed, and dura mater was repaired through the approximation with resorbable wire polyglactin 910 5-0, oxidized cellulose application, and bonding with human fibrin sealant (fibrinogen, thrombin, and calcium chloride). Sinusectomy, frontal sinus, and nasofrontal duct obliteration with pedicled pericranium flap were performed. Tomographically, a reanatomization was noted in frontal region, and a 12-month follow-up showed no complication. The use of fibrin glue to repair dura mater lacerations, as well as the pedicle pericranium flap for frontal sinus and nasofrontal duct obliteration, is an efficient method for treating fractures of the frontal bone.

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Many methods based on biometrics such as fingerprint, face, iris, and retina have been proposed for person identification. However, for deceased individuals, such biometric measurements are not available. In such cases, parts of the human skeleton can be used for identification, such as dental records, thorax, vertebrae, shoulder, and frontal sinus. It has been established in prior investigations that the radiographic pattern of frontal sinus is highly variable and unique for every individual. This has stimulated the proposition of measurements of the frontal sinus pattern, obtained from x-ray films, for skeletal identification. This paper presents a frontal sinus recognition method for human identification based on Image Foresting Transform and shape context. Experimental results (ERR = 5,82%) have shown the effectiveness of the proposed method.

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The purpose of this study was to evaluate the repair process in the reconstruction of the anterior wall of the frontal sinus of monkeys with bovine bone matrix. Four adult Cebus apella monkeys underwent an ostectomy of the anterior wall of the frontal sinus. The frontal sinus mucosa and the nasofrontal duct were not manipulated. Reconstruction occurred with implants of bovine bone matrix laminae measuring 2.0 x 2.5 cm and 0.4 mm thick, stabilized under pressure in the lateral wall of the frontal sinus. The monkeys were sacrificed over a period of 150 days and routine laboratory procedures were followed for hematoxylin-eosin staining and histologic evaluation of the specimens. Neoformed bone tissue was observed in contact with the frontal sinus mucosa and the bovine bone matrix. The frontal sinus mucosa remained whole without fibrous tissue or cystic formations. There was no occurrence of cellularization as well as revascularization of the bovine bone matrix, though it has permitted bone conduction on this surface. It was possible to conclude that the demineralized bovine bone matrix was biotolerable, being incorporated into the bone without the presence of inflammatory cells with characteristics of inertness and antigenicity and behaved as an osteoconductive material.

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The frontal sinus fractures are derived from accidents of great intensity. Are usually associated with fractures of the midface, including the naso-orbital fractures and zygomatic ethmoid. Several treatment modalities have been proposed. In this case it was used to access bicoronal reconstruction of the anterior frontal sinus, and restore contour fronto-naso-orbital-ethmoid with satisfactory results.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Purpose: To compare 2 methods used to determine the disk position based on sagittal magnetic resonance images. Patients and Methods: A cross-sectional study of patients with the signs and symptoms of temporomandibular disorders was conducted. The patients' ages and gender distributions were collected. The disk position diagnosis from the clinical examination was considered the primary outcome. Three observers evaluated the presence of anterior displacement on magnetic resonance images according to 2 criteria: method 1 (12-o'clock position) and method 2 (location of the intermediate zone). To assess the intraobserver variability of the 2 methods, the examiners evaluated the same magnetic resonance images at the beginning of the study (time 1) and 40 days later (time 2). The intraobserver agreement was assessed using the observed agreement and the kappa statistic. McNemar's test was used to assess the differences between each method and the clinical examination findings (P < .05). The accuracy, sensitivity, specificity, and positive and negative predictive values were calculated by comparing the diagnosis from each method with that from the clinical examination (considered the reference standard). Results: The final sample was composed of 20 subjects with a mean age of 33.0 +/- 33.7 years; 3 were men (15%) and 17 were women (85%). A statistically significant difference between the 2 methods was found. Method 1 yielded a greater percentage of anterior displaced disks (52.5%). The agreement between the clinical diagnosis and method 1 was lower (70.0%) than that between the clinical diagnosis and method 2 (87.5%). No statistically significant difference was found between the clinical diagnosis and method 2. Conclusion: The disk position should be judged according to the intermediate zone criterion. (C) 2012 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 70:1534-1539, 2012

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The main purposes of this manuscript are to provide an overview of various modalities of surgical correction of anterior plagiocephaly and to emphasize their differences with the classic open frontal-orbital advancement. Advancement of technology provides development of many other ways to achieve the same results. The authors describe the classic open frontal-orbital advancement and compare with other proposed techniques for correction of frontal plagiocephaly. The main limitation of the use of new forms of treatment of the anterior plagiocephaly is the age of the patient. There is still no consensus on criteria for quantitative evaluation of surgical results, and new forms of treatment do not present results with long follow-up. Frontal-orbital advancement is the preferred procedure to correct unicoronal synostosis due to its universal indication regardless of the age and degree of deformation of the anterior plagiocephaly.