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1.
Biochim Biophys Acta ; 1797(8): 1555-62, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20471951

RESUMO

Treatment with the omega-3 polyunsaturated fatty acids (PUFAs) docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) exerts cardioprotective effects, and suppresses Ca2+-induced opening of the mitochondrial permeability transition pore (MPTP). These effects are associated with increased DHA and EPA, and lower arachidonic acid (ARA) in cardiac phospholipids. While clinical studies suggest the triglyceride lowering effects of DHA and EPA are equivalent, little is known about the independent effects of DHA and EPA on mitochondria function. We compared the effects of dietary supplementation with the omega-3 PUFAs DHA and EPA on cardiac mitochondrial phospholipid fatty acid composition and Ca2+-induced MPTP opening. Rats were fed a standard lab diet with either normal low levels of omega-3 PUFA, or DHA or EPA at 2.5% of energy intake for 8 weeks, and cardiac mitochondria were isolated and analyzed for Ca2+-induced MPTP opening and phospholipid fatty acyl composition. DHA supplementation increased both DHA and EPA and decreased ARA in mitochondrial phospholipid, and significantly delayed MPTP opening as assessed by increased Ca2+ retention capacity and decreased Ca2+-induced mitochondria swelling. EPA supplementation increased EPA in mitochondrial phospholipids, but did not affect DHA, only modestly lowered ARA, and did not affect MPTP opening. In summary, dietary supplementation with DHA but not EPA, profoundly altered mitochondrial phospholipid fatty acid composition and delayed Ca2+-induced MPTP opening.


Assuntos
Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácido Eicosapentaenoico/administração & dosagem , Ácidos Graxos/análise , Mitocôndrias Cardíacas/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/fisiologia , Fosfolipídeos/análise , Animais , Cálcio/metabolismo , Suplementos Nutricionais , Masculino , Mitocôndrias Cardíacas/química , Poro de Transição de Permeabilidade Mitocondrial , Consumo de Oxigênio , Ratos , Ratos Wistar
2.
J Pharmacol Exp Ther ; 335(1): 155-62, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20624993

RESUMO

Intake of fish oil containing docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) prevents heart failure; however, the mechanisms are unclear. Mitochondrial permeability transition pore (MPTP) opening contributes to myocardial pathology in cardiac hypertrophy and heart failure, and treatment with DHA + EPA delays MPTP opening. Here, we assessed: 1) whether supplementation with both DHA and EPA is needed for optimal prevention of MPTP opening, and 2) whether this benefit occurs in hypertrophied myocardium. Rats with either normal myocardium or cardiac hypertrophy induced by 8 weeks of abdominal aortic banding were fed one of four diets: control diet without DHA or EPA or diets enriched with either DHA, EPA, or DHA + EPA (1:1 ratio) at 2.5% of energy intake for 17 weeks. Aortic banding caused a 27% increase in left ventricular mass and 25% depletion in DHA in mitochondrial phospholipids in rats fed the control diet. DHA supplementation raised DHA in phospholipids ∼2-fold in both normal and hypertrophied hearts and increased EPA. DHA + EPA supplementation also increased DHA, but to a lesser extent than DHA alone. EPA supplementation increased EPA, but did not affect DHA compared with the control diet. Ca(2+)-induced MPTP opening was delayed by DHA and DHA + EPA supplementation in both normal and hypertrophied hearts, but EPA had no effect on MPTP opening. These results show that supplementation with DHA alone effectively increases both DHA and EPA in cardiac mitochondrial phospholipids and delays MPTP and suggest that treatment with DHA + EPA offers no advantage over DHA alone.


Assuntos
Cálcio/farmacologia , Cardiomegalia/metabolismo , Ácidos Docosa-Hexaenoicos/farmacologia , Ácido Eicosapentaenoico/farmacologia , Mitocôndrias Cardíacas/metabolismo , Animais , Ácido Araquidônico/metabolismo , Cardiomegalia/diagnóstico por imagem , Dieta , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/metabolismo , Ácido Eicosapentaenoico/metabolismo , Eletrocardiografia , Ácidos Graxos/metabolismo , Masculino , Mitocôndrias Cardíacas/efeitos dos fármacos , Miocárdio/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Permeabilidade/efeitos dos fármacos , Fosfolipídeos/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/isolamento & purificação , Ratos , Ratos Wistar , Triglicerídeos/metabolismo , Ultrassonografia
3.
J Med Imaging (Bellingham) ; 7(3): 035001, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32411814

RESUMO

Purpose: Measurement of global spinal alignment (GSA) is an important aspect of diagnosis and treatment evaluation for spinal deformity but is subject to a high level of inter-reader variability. Approach: Two methods for automatic GSA measurement are proposed to mitigate such variability and reduce the burden of manual measurements. Both approaches use vertebral labels in spine computed tomography (CT) as input: the first (EndSeg) segments vertebral endplates using input labels as seed points; and the second (SpNorm) computes a two-dimensional curvilinear fit to the input labels. Studies were performed to characterize the performance of EndSeg and SpNorm in comparison to manual GSA measurement by five clinicians, including measurements of proximal thoracic kyphosis, main thoracic kyphosis, and lumbar lordosis. Results: For the automatic methods, 93.8% of endplate angle estimates were within the inter-reader 95% confidence interval ( CI 95 ). All GSA measurements for the automatic methods were within the inter-reader CI 95 , and there was no statistically significant difference between automatic and manual methods. The SpNorm method appears particularly robust as it operates without segmentation. Conclusions: Such methods could improve the reproducibility and reliability of GSA measurements and are potentially suitable to applications in large datasets-e.g., for outcome assessment in surgical data science.

4.
Acad Radiol ; 25(6): 811-818, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29555567

RESUMO

RATIONALE AND OBJECTIVES: The purpose of this study was to integrate web-based forms with a zero-footprint cloud-based Picture Archiving and Communication Systems (PACS) to create a tool of potential benefit to radiology research and education. MATERIALS AND METHODS: Web-based forms were created with a front-end and back-end architecture utilizing common programming languages including Vue.js, Node.js and MongoDB, and integrated into an existing zero-footprint cloud-based PACS. RESULTS: The web-based forms application can be accessed in any modern internet browser on desktop or mobile devices and allows the creation of customizable forms consisting of a variety of questions types. Each form can be linked to an individual DICOM examination or a collection of DICOM examinations. CONCLUSIONS: Several uses are demonstrated through a series of case studies, including implementation of a research platform for multi-reader multi-case (MRMC) studies and other imaging research, and creation of an online Objective Structure Clinical Examination (OSCE) and an educational case file.


Assuntos
Computação em Nuvem , Radiologia , Software , Pesquisa Biomédica/instrumentação , Pesquisa Biomédica/métodos , Humanos , Internet , Radiologia/educação , Radiologia/métodos , Sistemas de Informação em Radiologia/tendências , Tecnologia Radiológica/educação , Tecnologia Radiológica/métodos , Tecnologia Radiológica/tendências
5.
Neuroradiol J ; 28(2): 87-96, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25963153

RESUMO

Functional imaging modalities, such as functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI), are rapidly changing the scope and practice of neuroradiology. While these modalities have long been used in research, they are increasingly being used in clinical practice to enable reliable identification of eloquent cortex and white matter tracts in order to guide treatment planning and to serve as a diagnostic supplement when traditional imaging fails. An understanding of the scientific principles underlying fMRI and DTI is necessary in current radiological practice. fMRI relies on a compensatory hemodynamic response seen in cortical activation and the intrinsic discrepant magnetic properties of deoxy- and oxyhemoglobin. Neuronal activity can be indirectly visualized based on a hemodynamic response, termed neurovascular coupling. fMRI demonstrates utility in identifying areas of cortical activation (i.e., task-based activation) and in discerning areas of neuronal connectivity when used during the resting state, termed resting state fMRI. While fMRI is limited to visualization of gray matter, DTI permits visualization of white matter tracts through diffusion restriction along different axes. We will discuss the physical, statistical and physiological principles underlying these functional imaging modalities and explore new promising clinical applications.


Assuntos
Encefalopatias/fisiopatologia , Encefalopatias/cirurgia , Encéfalo/fisiopatologia , Encéfalo/cirurgia , Neuroimagem Funcional/métodos , Imageamento por Ressonância Magnética/métodos , Cirurgia Assistida por Computador/métodos , Humanos
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