Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros

Base de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
AJR Am J Roentgenol ; 188(3): W276-80, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17312036

RESUMO

OBJECTIVE: We describe the application of an optical flow method to inspiratory and expiratory high-resolution volumetric lung MDCT for the assessment of regional air trapping. CONCLUSION: Qualitative and quantitative assessment of regional air trapping is feasible using an optical flow method to align volumetric MDCT data sets.


Assuntos
Medidas de Volume Pulmonar/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Espaço Morto Respiratório , Reologia/métodos , Tomografia Computadorizada por Raios X/métodos , Expiração , Estudos de Viabilidade , Humanos , Imageamento Tridimensional/métodos , Inalação , Óptica e Fotônica , Ventilação Pulmonar , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Técnica de Subtração
2.
Circulation ; 112(9): 1274-83, 2005 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-16129812

RESUMO

BACKGROUND: Whether mechanical restraint of the left ventricle (LV) can influence remodeling after myocardial infarction (MI) remains poorly understood. This study surgically placed a cardiac support device (CSD) over the entire LV and examined LV and myocyte geometry and function after MI. METHODS AND RESULTS: Post-MI sheep (35 to 45 kg; MI size, 23+/-2%) were randomized to placement of the CorCap CSD (Acorn Cardiovascular, Inc) (MI+CSD; n=6) or remained untreated (MI only; n=5). Uninstrumented sheep (n=10) served as controls. At 3 months after MI, LV end-diastolic volume (by MRI) was increased in the MI only group compared with controls (98+/-8 versus 43+/-4 mL; P<0.05). In the MI+CSD group, LV end-diastolic volume was lower than MI only values (56+/-7 mL; P<0.05) but remained higher than controls (P<0.05). Isolated LV myocyte shortening velocity was reduced by 35% from control values (P<0.05) in both MI groups. LV myocyte beta-adrenergic response was reduced with MI but normalized in the MI+CSD group. LV myocyte length increased in the MI group and was reduced in the MI+CSD group. Relative collagen content was increased and matrix metalloproteinase-9 was decreased within the MI border region of the CSD group. CONCLUSIONS: A CSD beneficially modified LV and myocyte remodeling after MI through both cellular and extracellular mechanisms. These findings provide evidence that nonpharmacological strategies can interrupt adverse LV remodeling after MI.


Assuntos
Coração Auxiliar , Infarto do Miocárdio/cirurgia , Miocárdio/patologia , Remodelação Ventricular , Actinas/análise , Animais , Colágeno/análise , Matriz Extracelular/fisiologia , Masculino , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 9 da Matriz/análise , Contração Miocárdica , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miócitos Cardíacos/patologia , Miócitos Cardíacos/fisiologia , Ovinos , Inibidores Teciduais de Metaloproteinases/análise , Função Ventricular Esquerda
3.
Psychon Bull Rev ; 9(4): 706-13, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12613673

RESUMO

Rats learn the spatial pattern in which hidden caches of food are located. Once the pattern is learned, finding one or more baited locations provides (positive) information about the remaining baited locations. In the present experiment, we examined whether negative information (the absence of food in a location) would also be used in locating the remaining baited locations. Rats were tested in an apparatus containing a matrix of vertical poles, on top of which food could be hidden. At the beginning of the trial, the location of the baited poles was unpredictable, but the poles were always arranged in a linear pattern. The rats learned the pattern and used both positive and negative information in locating baited poles.


Assuntos
Comportamento Apetitivo , Comportamento de Escolha , Orientação , Reconhecimento Visual de Modelos , Animais , Masculino , Rememoração Mental , Resolução de Problemas , Ratos , Ratos Sprague-Dawley
4.
Vascular ; 17(6): 359-64, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19909685

RESUMO

Isolated dissection of the origin of both celiac and superior mesenteric arteries is a rare vascular pathology with limited management guidelines. The presentation is generally nonspecific, most often manifesting with epigastric pain radiating to the back. A high diagnostic index of suspicion and stepwise management are essential for a successful outcome. This case report details the clinical course of a 57-year-male who presented with a 2-week history of epigastric discomfort with back pain and was found to have focal celiac artery dissection with aneurysmal dilation of 1.2 cm. His vital signs were stable, and the physical examination was unremarkable. At this time, he was placed on antiplatelet medication and was scheduled for endovascular repair of his celiac aneurysm with a covered stent graft. Two weeks later, recurrent abdominal pain prompted a repeat computed tomographic scan that revealed sequential superior mesenteric artery (SMA) dissection. The patient was admitted and anticoagulated. A complete workup ruled out underlying collagen vascular and autoimmune pathology. He remained stable, with significant symptomatic improvement. After 6 months, anticoagulation was discontinued and antiplatelet therapy was instituted for long-term management. Subsequent operative or endovascular intervention was not required. The patient was continuing to do well on his 18-month clinical follow-up. There are 71 cases of SMA and 12 cases of celiac artery dissection in the literature. This report outlines this rare presentation of isolated, proximal sequential celiac artery and SMA dissection. This case illustrates that conservative management may be warranted in uncomplicated, isolated visceral arterial dissection.


Assuntos
Anticoagulantes/administração & dosagem , Dissecção Aórtica/tratamento farmacológico , Artéria Celíaca , Artéria Mesentérica Superior , Inibidores da Agregação Plaquetária/administração & dosagem , Dor Abdominal/etiologia , Dissecção Aórtica/complicações , Dissecção Aórtica/diagnóstico , Dor nas Costas/etiologia , Artéria Celíaca/diagnóstico por imagem , Esquema de Medicação , Humanos , Masculino , Artéria Mesentérica Superior/diagnóstico por imagem , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Ultrassonografia
5.
Ann Thorac Surg ; 80(6): 2257-62, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16305885

RESUMO

BACKGROUND: Early infarct expansion impairs function of normally perfused borderzone myocardium (BZM), initiates adverse remodeling, and portends a poor long-term outcome. Early ventricular restraint has been demonstrated to improve global remodeling but its effect on BZM function has not been assessed. Using an ovine model of infarct induced remodeling and MRI, we tested the hypothesis that ventricular restraint early after MI preserves BZM function and reduces remodeling. METHODS: Six sheep had a large anterior infarction after ligation of all diagonal branches. One week after infarction 3 sheep had placement of a cardiac support device (CSD) to restrain infarct expansion. Global remodeling and borderzone wall thickening strain were assessed using tagged MRI before and 8 weeks after infarction. RESULTS: Global remodeling was greatly reduced in the CSD group compared with control. The BZM systolic wall thickening was similar in both groups at baseline (13.5% +/- 2.0%, control; 12.8% +/- 2.0%, CSD, p = 0.8). After 8 weeks of infarction-induced remodeling, systolic wall thickening strain decreased significantly to 4.9% +/- 0.7% in the control group (p = 0.03). In contrast, systolic wall thickening was preserved in the CSD group at 8 weeks (11.0% +/- 1.6%, p = 0.3). In the control group all thickening occurred during isovolemic contraction, plateauing during ejection. The CSD improved late systolic borderzone wall thickening, although dynamics remained perturbed. CONCLUSIONS: Ventricular restraint early after MI improves both contractile function of the BZM and global ventricular remodeling. The dynamics of BZM wall thickening are impaired during remodeling. The CSD significantly improves but does not completely maintain baseline BZM wall thickening dynamics.


Assuntos
Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Remodelação Ventricular , Animais , Masculino , Ovinos , Fatores de Tempo
6.
Horm Behav ; 43(5): 531-9, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12799169

RESUMO

Plasma testosterone (T) was measured in control male and female rats on gestational days 16, 17, 18, 19, and 20 and on days 17-20 in males from dams who were fed ethanol and/or were stressed during pregnancy. Circulating T in control males showed an earlier rise, yielding a longer period of prenatal T elevation, than was reported previously (Endocrinology 106 (1980)306). Compared to control males, exposure to alcohol-alone augmented T on days 18 and 19, stress-alone attenuated prenatal T, and the combination of stress and alcohol completely blocked the normal rise in T between days 17 and 18. When these prenatal alterations in T are viewed along with effects these same treatments have on the postparturient T surge (Horm. Behav. 41 (2002) 229), a possible explanatory mechanism emerges for the uniquely different behavioral patterns of sexual behavior differentiation induced in males by prenatal exposure to alcohol, stress, or both factors. Whereas the potential for feminine behavior is retained to the extent that either the prenatal or the neonatal T surge is attenuated, the male potential is more sensitive to reductions in the fetal surge and is maximally disrupted if both the prenatal and the postparturitional T surges are suppressed.


Assuntos
Consumo de Bebidas Alcoólicas/fisiopatologia , Sangue Fetal/metabolismo , Complicações na Gravidez/fisiopatologia , Efeitos Tardios da Exposição Pré-Natal , Estresse Psicológico/fisiopatologia , Testosterona/sangue , Animais , Ingestão de Alimentos/fisiologia , Etanol , Feminino , Masculino , Análise por Pareamento , Exposição Materna , Gravidez , Ratos , Ratos Sprague-Dawley , Taxa Secretória , Caracteres Sexuais , Diferenciação Sexual , Testosterona/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA