986 resultados para PERIAQUEDUCTAL GRAY


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Development of adequate diving capabilities is crucial for survival of seal pups and may depend on age and body size. We tracked the diving behavior of 20 gray seal pups during their first 3 mo at sea using satellite relay data loggers. We employed quantile analysis to track upper limits of dive duration and percentage time spent diving, and lower limits of surface intervals. When pups first left the breeding colony, extreme (ninety-fifth percentile) dive duration and percentage time spent diving were positively correlated with age, but not mass, at departure. Extreme dive durations and percentage time spent diving peaked at [Formula: see text] d of age at values comparable with those of adults, but were not sustained. Greater peaks in extreme percentage time spent diving occurred in pups that had higher initial values, were older at their peak, and were heavier at departure. Pups that were smaller and less capable divers when they left the colony improved extreme dive durations and percentage time spent diving more rapidly, once they were at sea. Minimum survival time correlated positively with departure mass. Pups that were heavier at weaning thus benefitted from being both larger and older at departure, but smaller pups faced a trade-off. While age at departure had a positive effect on early dive performance, departure mass impacted on peak percentage time spent diving and longer-term survival. We speculate that once small pups have attained a minimum degree of physiological development to support diving, they would benefit by leaving the colony when younger but larger to maximize limited fuel reserves, rather than undergoing further maturation on land away from potential food resources, because poor divers may be able to "catch up" once at sea.

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Leptin is a multifunctional hormone, produced predominantly in adipocytes. It regulates energy balance through its impact on appetite and fat metabolism, and its concentration indicates the size of body fat reserves. Leptin also plays a vital role in stretch-induced surfactant production during alveolar development in the fetus. The structure, expression pattern, and role of leptin have not previously been explored in marine mammals. Phocid seals undergo cyclical changes in body composition as a result of prolonged fasting and intensive foraging bouts and experience rapid, dramatic, and repeated changes in lung volume during diving. Here, we report the tissue-specific expression pattern of leptin in these animals. This is the first demonstration of leptin expression in the lung tissue of a mature mammal, in addition to its expression in the blubber and bone marrow, in common with other animals. We propose a role for leptin in seal pulmonary surfactant production, in addition to its likely role in long-term energy balance. We identify substitutions in the phocine leptin sequence in regions normally highly conserved between widely distinct vertebrate groups, and, using a purified seal leptin antiserum, we confirm the presence of the leptin protein in gray seal lung and serum fractions. Finally, we report the substantial inadequacies of using heterologous antibodies to measure leptin in unextracted gray seal serum.

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This research aims to study wall paitings created by artists Newton Navarro and Dorian Gray, installed in public buildings of modern architecture, in Natal/RN from 1950 to 1970. The subject is seen by focusing on its concepts and characterization, linked to the ideia of integration of the arts and the meaning of modern mural painting in Brasil. The study presents an analyses of those paitings considering themes, techiniques and dimensions, comparing the solutions of local artists with brasilian muralist painters, particularly the work of Cândido Portinari. Registers of artistic works show a view of the inclusion of arts in modern architecture in the city

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Uno de los aspectos más documentados a la hora de estudiar las obras de Óscar Wilde en profundidad ha sido el concepto de máscara u ocultación. Este concepto fue tratado a su vez por el propio escritor en su ensayo titulado The Truth of Masks (1891), donde analiza, entre otras cosas, la puesta en escena y los objetos que aparecen a la hora de llevar a cabo la representación de las obras de teatro de Shakespeare. Por otra parte, no es necesario señalar que Wilde es harto reconocido por su gusto por la filosofía del arte y la estética, o mejor dicho, por su afinidad y apología al arte por el arte, así como también se le asocia con la figura del dandy decandente y esteta. Precisamente ambos aspectos, tanto el de la ocultación como el de la filosofía del arte y la estética, nos servirán como ineludible punto de partida para este estudio, que, mediante el análisis cultural de sus obras más representativas, completarán la recepción actual existente de Wilde. Se verá en este estudio que una faceta indispensable del escritor recae principalmente en la aportación que realiza el artesano, en estrecha comunión con el artista, tal y como él mismo defendió en numerosos de sus ensayos-conferencias, en los que propugnaba el individualismo mediante la realización del ser, en el plano artístico. Se ha llevado a cabo por tanto, un exhaustivo análisis para profundizar aún más en la conexión que existe entre estos conceptos, y ahondando por ende en la visión del artista artesano, que justificará ese nuevo perfil consumado del escritor, a través del análisis de los objetos en sus obras, escritos e, incluso, en su propia persona, entendida ésta como creación artística. No en vano, Wilde es el escritor que nos permite retomar el sentido etimológico de la palabra ‘persona’, para descubrir que, en su origen, ésta significaba ‘máscara’, y que consiguientemente, entronca directamente con la persona del escritor, y nos hace volver a plantearnos dónde empieza o acaba la máscara y dónde su propia persona artística...

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El presente estudio refleja los argumentos teóricos y propuestas en el campo de la investigación artística, que resultaron de la autoreflexión en torno a la tesis Art Realities y el proyecto artístico visual The Cloudwalkers, que el autor realizó para la obtención del grado MFA in New Media en la Danube Universität (Austria), en colaboración con el Transart Institute (E.U.A.). Es un análisis autocrítico de caso que abarca tanto la parte escrita como práctica del proyecto de titulación, del que se deriva un estudio teórico que expone posibles instrumentos y estrategias de investigación para las artes visuales.

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This research aims to study wall paitings created by artists Newton Navarro and Dorian Gray, installed in public buildings of modern architecture, in Natal/RN from 1950 to 1970. The subject is seen by focusing on its concepts and characterization, linked to the ideia of integration of the arts and the meaning of modern mural painting in Brasil. The study presents an analyses of those paitings considering themes, techiniques and dimensions, comparing the solutions of local artists with brasilian muralist painters, particularly the work of Cândido Portinari. Registers of artistic works show a view of the inclusion of arts in modern architecture in the city

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To evaluate the modified US7 score (MUS7 score SYN) in the assessment of patients with early rheumatoid arthritis (ERA). In addition, dorsal and palmar recesses of the wrists as well as of small joints of the hands and feet were examined for the presence of synovitis by means of a global assessment of joints. The study sample comprised 32 patients treated for arthritis, with an average disease duration of 13 months. An ultrasound machine with high frequency transducer was used. Hands were also X-rayed and analysed by Larsen score. Out of the 832 examined joints, synovitis was detected in 173 (20,79%), tenosynovitis in 22 (4,91%), and erosions in 3 (1,56%). Synovitis was predominantly detected in the dorsal recess (73,38%) of MCP and PIP joints, when compared with palmar recess (26%). The presence of synovitis in the joints evaluated correlated with clinical (HAQ-DI, DAS28), laboratory (ACPA, RF, CRP), and ultrasound results (r = 0,37 to r = 0,42; p = 0,04 to p = 0,003). We found correlation of the MUS7 score SYN of the gray scale US or of the power Doppler US with DAS28 (PCR) values (r = 0,38; p = 0,0332), and with CRP results (r = 0,39; p = 0,0280), respectively. The dorsal recess, the wrist, and small joints can be considered as important sites to detect synovitis by the MUS7 score SYN in patients with ERA.

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The pathological mechanisms underlying cognitive dysfunction in multiple sclerosis (MS) are not yet fully understood and, in addition to demyelinating lesions and gray-matter atrophy, subclinical disease activity may play a role. To evaluate the contribution of asymptomatic gadolinium-enhancing lesions to cognitive dysfunction along with gray-matter damage and callosal atrophy in relapsing-remitting MS (RRMS) patients. Forty-two treated RRMS and 30 controls were evaluated. MRI (3T) variables of interest were brain white-matter and cortical lesion load, cortical and deep gray-matter volumes, corpus callosum volume and presence of gadolinium-enhancing lesions. Outcome variables included EDSS, MS Functional Composite (MSFC) subtests and the Brief Repeatable Battery of Neuropsychological tests. Cognitive dysfunction was classified as deficits in two or more cognitive subtests. Multivariate regression analyses assessed the contribution of MRI metrics to outcomes. Patients with cognitive impairment (45.2%) had more cortical lesions and lower gray-matter and callosal volumes. Patients with subclinical MRI activity (15%) had worse cognitive performance. Clinical disability on MSFC was mainly associated with putaminal atrophy. The main independent predictors for cognitive deficits were high burden of cortical lesions and number of gadolinium-enhancing lesions. Cognitive dysfunction was especially related to high burden of cortical lesions and subclinical disease activity. Cognitive studies in MS should look over subclinical disease activity as a potential contributor to cognitive impairment.

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A ocorrência de Giardia, Cryptosporidium e microsporídios foi investigada por meio da análise de 98 amostras fecais de animais silvestres capturados em uma área de desmatamento para a construção das barragens de Paraitinga e Biritiba, localizadas nos Municípios de Mogi das Cruzes, Salesópolis e Biritiba-Mirim, no Estado de São Paulo. As amostras foram obtidas de 46 roedores, 21 marsupiais, 16 sapos, nove morcegos, três primatas e três lagartos. As técnicas de centrífugo-flutuação com sulfato de zinco, de Kinyoun e a coloração de Gram-Chromotrope foram utilizadas, respectivamente, para a pesquisa de Giardia, de Cryptosporidium e de microsporídios. O total de animais parasitados por um dos protozoários investigados foi de 17,35% (17/98). Cistos de Giardia foram encontrados em amostras fecais de dois pequenos roedores da espécie Coendou villosus (ouriço-cacheiro). Os três animais positivos para Cryptosporidium foram roedores das espécies Akodon montensis, Thaptomys nigrita (ambos conhecidos como ratos do mato) e Sciurus aestuans (serelepe ou caxinguelê). Esporos de microsporídios foram encontrados nas fezes de 12 animais, sendo seis roedores das espécies Oligoryzomys sp.(um), Akodon montensis (três) e Coendou villosus (dois), três marsupiais pertencentes às espécies Didelphis aurita (dois) e Marmosops incanus (um) e três morcegos da espécie Diphylla ecaudata. Este é o primeiro relato de microsporidiose em animais silvestres no Brasil. A presente investigação enfatiza a importância de animais silvestres, particularmente pequenos mamíferos, como potenciais fontes de infecção desses protozoários para outras populações animais, incluindo o homem, em áreas de desmatamento.

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A imagem por ressonância magnética (IRM) é o método de diagnóstico por imagem não invasivo mais sensível para avaliar as partes moles, particularmente o encéfalo, porém trata-se de uma técnica onerosa. O método fundamenta-se no fenômeno da ressonância magnética nuclear que ocorre quando núcleos atômicos com propriedades magnéticas presentes no corpo são submetidos a um campo magnético intenso, sendo posteriormente excitados por energia de radiofrequência e gerando, por sua vez, um sinal de onda de radiofrequência capaz de ser captado por uma antena receptora, passando por um processo matemático, chamado Transformada de Fourier, para posterior formação da imagem. Esse estudo objetivou realizar 10 exames completos da cabeça em cadáveres de cães normais à IRM e confeccionar um Atlas com as estruturas identificadas. As imagens foram adquiridas em um aparelho de ressonância magnética Gyroscan S15/HP Philips com campo magnético de 1,5Tesla. Os cadáveres foram posicionados com a cabeça no interior de uma bobina de cabeça humana e foram submetidos a cortes iniciais sagitais a partir de onde se planejou os cortes transversais e dorsais nas sequências de pulso spin-eco T1, T2 e DP. Em T1 utilizou-se TR=400ms e TE=30ms, T2 utilizou-se TR=2000ms e TE=80ms e na DP utilizou-se TR=2000ms e TE=30ms. A espessura do corte foi de 4mm, o número de médias foi igual a 2, a matriz foi de 256x256, o fator foi igual a 1,0 e o campo de visão foi de 14cm. A duração do exame completo da cabeça foi de 74,5minutos. As imagens obtidas com as sequências utilizadas e com a bobina de cabeça humana foram de boa qualidade. Em T1 a gordura tornou-se hiperintensa e o líquido hipointenso. Em T2 a gordura ficou menos hiperintensa e o líquido hiperintenso. A cortical óssea e o ar foram hipointensos em todas as sequências utilizadas devido a baixa densidade de prótons. A sequência DP mostrou o melhor contraste entre a substância branca e cinzenta quando comparada a T2 e a T1. T2 evidenciou o líquido cefalorraquidiano tornando possível a distinção dos sulcos e giros cerebrais. Através do exame de IRM foi possível, pelo contraste, identificar as estruturas ósseas componentes da arquitetura da região, músculos, grandes vasos venosos e arteriais e estruturas do sistema nervoso central, além de elementos do sistema digestório, respiratório e estruturas dos olhos entre outras. Nesse estudo as IRM adquiridas nas sequências T1, DP e T2 foram complementares para o estudo dos aspectos anatômicos da cabeça de cães demonstrando-os com riqueza de detalhes. O tempo requerido para o exame completo da cabeça é compátivel para uso em animais vivos desde que devidamente anestesiados e controlados. Os resultados obtidos por esse trabalho abrem caminho em nosso meio, para o estudo de animais vivos e para o início da investigação de doenças, principalmente as de origem neurológica, visto ser esta técnica excelente para a visibilização do encéfalo.

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Due to its relationship with other properties, wood density is the main wood quality parameter. Modern, accurate methods - such as X-ray densitometry - are applied to determine the spatial distribution of density in wood sections and to evaluate wood quality. The objectives of this study were to determinate the influence of growing conditions on wood density variation and tree ring demarcation of gmelina trees from fast growing plantations in Costa Rica. The wood density was determined by X-ray densitometry method. Wood samples were cut from gmelina trees and were exposed to low X-rays. The radiographic films were developed and scanned using a 256 gray scale with 1000 dpi resolution and the wood density was determined by CRAD and CERD software. The results showed tree-ring boundaries were distinctly delimited in trees growing in site with rainfall lower than 25 10 mm/year. It was demonstrated that tree age, climatic conditions and management of plantation affects wood density and its variability. The specific effect of variables on wood density was quantified by for multiple regression method. It was determined that tree year explained 25.8% of the total variation of density and 19.9% were caused by climatic condition where the tree growing. Wood density was less affected by the intensity of forest management with 5.9% of total variation.

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Objectives: Adults with major depressive disorder (MDD) are reported to have reduced orbitofrontal cortex (OFC) volumes, which could be related to decreased neuronal density. We conducted a study on medication naive children with MDD to determine whether abnormalities of OFC are present early in the illness course. Methods: Twenty seven medication naive pediatric Diagnostic and Statistical Manual of Mental Disorders, 4(th) edition (DSM-IV) MDD patients (mean age +/- SD = 14.4 +/- 2.2 years; 10 males) and 26 healthy controls (mean age +/- SD = 14.4 +/- 2.4 years; 12 males) underwent a 1.5T magnetic resonance imaging (MRI) with 3D spoiled gradient recalled acquisition. The OFC volumes were compared using analysis of covariance with age, gender, and total brain volume as covariates. Results: There was no significant difference in either total OFC volume or total gray matter OFC volume between MDD patients and healthy controls. Exploratory analysis revealed that patients had unexpectedly larger total right lateral (F = 4.2, df = 1, 48, p = 0.05) and right lateral gray matter (F = 4.6, df = 1, 48, p = 0.04) OFC volumes compared to healthy controls, but this finding was not significant following statistical correction for multiple comparisons. No other OFC subregions showed a significant difference. Conclusions: The lack of OFC volume abnormalities in pediatric MDD patients suggests the abnormalities previously reported for adults may develop later in life as a result of neural cell loss.

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Objective: The striatum, including the putamen and caudate, plays an important role in executive and emotional processing and may be involved in the pathophysiology of mood disorders. Few studies have examined structural abnormalities of the striatum in pediatric major depressive disorder (MDD) patients. We report striatal volume abnormalities in medication-naive pediatric MDD compared to healthy comparison subjects. Method: Twenty seven medication-naive pediatric Diagnostic and Statistical Manual of Mental Disorders, 4(th) edition (DSM-IV) MDD and 26 healthy comparison subjects underwent volumetric magnetic resonance imaging (MRI). The putamen and caudate volumes were traced manually by a blinded rater, and the patient and control groups were compared using analysis of covariance adjusting for age, sex, intelligence quotient, and total brain volumes. Results: MDD patients had significantly smaller right striatum (6.0% smaller) and right caudate volumes (7.4% smaller) compared to the healthy subjects. Left caudate volumes were inversely correlated with severity of depression in MDD subjects. Age was inversely correlated with left and right putamen volumes in MDD patients but not in the healthy subjects. Conclusions: These findings provide fresh evidence for abnormalities in the striatum of medication-naive pediatric MDD patients and suggest the possible involvement of the striatum in the pathophysiology of MDD.

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Background: Matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of MMP (TIMP) promote derangement of the extracellular matrix, which is ultimately reflected in plaque images seen on ultrasound. Videodensitometry can identify structural disturbances in plaques. Objectives: To establish the correlations between values determined using videodensitometry in B-mode ultrasound images of advanced carotid plaques and the total expression of MMP-9 and TIMP-1 in these removed plaques. Methods: Thirty patients underwent ultrasonic tissue characterization of carotid plaques before surgery, using mean gray level (MGL), energy, entropy and homogeneity. Each patient was assigned preoperatively to one of 2 groups: group I, symptomatic patients (n = 16; 12 males; mean age 66.7 +/- 6.8 years), and group II, asymptomatic patients (n = 14; 8 males; mean age 67.6 +/- 6.81 years). Tissue specimens were analyzed for MMP-9 and TIMP-1 expression. Nine carotid arteries were used as normal tissue controls. Results: MMP-9 expression levels were elevated in group II and in normal tissues compared to group I (p < 0.001). TIMP-1 levels were higher in group II than in group I, and significantly higher in normal tissues than in group I (p = 0.039). The MGL was higher in group II compared to group I (p = 0.038). Energy had greater values in group II compared to group I (p = 0.02). There were no differences between patient groups in homogeneity and entropy. Energy positively correlated with MMP-9 and TIMP-1 expression (p = 0.012 and p = 0.031 respectively). Homogeneity positively correlated with MMP-9 and TIMP-1 expression (p = 0.034 and p = 0.047 respectively). There were no correlations between protein expression and MGL or entropy. Conclusions: Videodensitometric computer analysis of ultrasound scanning images can be used to identify stable carotid plaques, which have higher total expression levels of MMP-9 and TIMP-1 than unstable plaques.