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1.
Am J Emerg Med ; 31(9): 1422.e3-5, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23773771

RESUMO

Syncope accounts for approximately 1% to 2% of emergency department visits each year and up to 6% of hospital admissions [1,2]. The causes of syncope are numerous, from common benign disorders to life-threatening processes including transient ischemic attack and even stroke. Although cervicocerebral artery dissection is an uncommon etiology in ischemic stroke, it is the second leading cause in patients younger than 45 years, and most of them predominantly involved the extracranial artery [3-5]. Dissections of intracranial arteries are increasingly being recognized with advanced imaging study; however, isolated basilar artery dissection (IBAD) is rarely reported. Here, we present a case of a 32-year-old man who presented to our emergency department with the chief complaint of syncope and finally diagnosed with acute ischemic stroke resulted from IBAD.


Assuntos
Dissecção Aórtica/complicações , Artéria Basilar , Acidente Vascular Cerebral/etiologia , Adulto , Dissecção Aórtica/diagnóstico , Dissecção Aórtica/diagnóstico por imagem , Artéria Basilar/diagnóstico por imagem , Serviço Hospitalar de Emergência , Humanos , Imageamento por Ressonância Magnética , Masculino , Neuroimagem , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X
2.
Lab Chip ; 13(6): 1114-20, 2013 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-23348149

RESUMO

Using a cell culture chip with a deformable substrate driven by a hydraulic force, we investigated the motility of cancer cells affected by myofibroblasts undergoing cyclic tensile strain (CTS). CTS reduced both the expression of α-smooth muscle actin in the myofibroblast and the ability of the myofibroblast to accelerate cancer cell migration. However, with the treatment of a pro-inflammatory factor interleukin-1ß on the myofibroblasts, the effects of CTS on the myofibroblast were diminished. This result suggests an antagonism between mechanical and chemical stimulations on mediating cancer metastasis by the stromal myofibroblast.


Assuntos
Técnicas Analíticas Microfluídicas/métodos , Miofibroblastos/metabolismo , Actinas/metabolismo , Animais , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Humanos , Interleucina-1beta/farmacologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Técnicas Analíticas Microfluídicas/instrumentação , Miofibroblastos/citologia , Células NIH 3T3 , Fator de Crescimento Transformador beta1/farmacologia
3.
Lab Chip ; 11(10): 1808-14, 2011 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-21491053

RESUMO

We use a microfluidic cell culture chip equipped with pneumatic microvalves to analyze the paracrine loop between lung cancer cells and fibroblasts. In order to assess the cellular responses in the paracrine loop, we measure the migration speeds of cancer cells and the aspect ratios of fibroblasts which reflect the phenotype of myofibroblasts. With well-controlled interaction sequences between these two types of cells, we verify that the cytokines from cancer cells effectively stimulate the fibroblasts into myofibroblasts. The cytokines from myofibroblasts, rather than fibroblasts, increase the migration speeds of cancer cells. We confirm that the transforming growth factor-ß1 (TGF-ß1) is involved in the interaction between cancer cells and fibroblasts, and we also interrupt this paracrine loop in the cell culture chip by inhibiting the TGF-ß1 receptors on fibroblasts.


Assuntos
Técnicas Analíticas Microfluídicas/instrumentação , Comunicação Parácrina , Microambiente Tumoral , Actinas/metabolismo , Benzamidas/farmacologia , Linhagem Celular , Movimento Celular , Dioxóis/farmacologia , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Técnicas Analíticas Microfluídicas/métodos , Miofibroblastos/citologia , Miofibroblastos/metabolismo , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Fator de Crescimento Transformador beta1/metabolismo
4.
IEEE Trans Syst Man Cybern B Cybern ; 38(6): 1537-48, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19022725

RESUMO

This paper proposes a type-2 self-organizing neural fuzzy system (T2SONFS) and its hardware implementation. The antecedent parts in each T2SONFS fuzzy rule are interval type-2 fuzzy sets, and the consequent part is of Mamdani type. Using interval type-2 fuzzy sets in T2SONFS enables it to be more robust than type-1 fuzzy systems. T2SONFS learning consists of structure and parameter identification. For structure identification, an online clustering algorithm is proposed to generate rules automatically and flexibly distribute them in the input space. For parameter identification, a rule-ordered Kalman filter algorithm is proposed to tune the consequent-part parameters. The learned T2SONFS is hardware implemented, and implementation techniques are proposed to simplify the complex computation process of a type-2 fuzzy system. The T2SONFS is applied to nonlinear system identification and truck backing control problems with clean and noisy training data. Comparisons between type-1 and type-2 neural fuzzy systems verify the learning ability and robustness of the T2SONFS. The learned T2SONFS is hardware implemented in a field-programmable gate array chip to verify functionality of the designed circuits.


Assuntos
Algoritmos , Lógica Fuzzy , Modelos Teóricos , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão/métodos , Simulação por Computador , Retroalimentação
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