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1.
Artigo em Chinês | MEDLINE | ID: mdl-31914300

RESUMO

Objective:To investigate the expression of BRCA1 associated protein(BRAP) and its correlations with clinicopathological features and prognosis of patients with laryngeal squamous cell carcinoma(LSCC). Method:The protein expression of BRAP in LSCC tissues and normal laryngeal tissues were assessed by immunohistochemistry and Western blot, and their correlations with clinicopathological features and prognosis were statistically analyzed. Result:The expression of BRAP in LSCC was significantly higher than that in normal laryngeal tissues(P<0.05). BRAP expression was significantly correlated with the TNM stage and lymph node metastasis(P<0.05). Kaplan-Meier survival analysis showed that LSCC patients with high BRAP expression had worse overall survival than those with low BRAP expression(P<0.01). Multivariate Cox proportional-hazards analysis showed that the high expression of BRAP protein was an important poor prognostic indicator of the patients. Conclusion:BRAP is related with the development of LSCC, and it may be used as an important prognostic biomarker for LSCC patients.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Laríngeas , Humanos , Metástase Linfática , Prognóstico , Ubiquitina-Proteína Ligases
2.
Clin Radiol ; 73(11): 983.e15-983.e22, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30093066

RESUMO

AIM: To determine the diagnostic performance of instantaneous wave-free ratio (iFR) derived from non-invasive coronary computed tomography angiography (CTA; iFRCT) for ischaemia-causing coronary stenosis, and to compare the diagnostic efficacy of iFRCT, CTA, and CTA plus iFRCT. METHODS AND MATERIALS: Thirty-nine patients (55 vessels) with known or suspected coronary artery disease were included. All patients underwent invasive coronary angiography and fractional flow reserve (FFR) according to CTA findings and clinical indicators. The same raw data used for CTA were used to build patient-specific computed flow dynamic models and to calculate iFRCT. RESULTS: On a vessel-based level, the correlation between iFRCT and FFR was moderate (r=0.65, p<0.05); the optimal iFRCT cut-off value was 0.85 based on an FFR cut-off value of 0.80, resulting in 85% sensitivity, 69% specificity, 61% positive predictive value (PPV), 89% negative predictive value (NPV), and 75% accuracy. The AUC showed significant differences between iFRCT and CTA (vessel-based: 0.84 versus 0.68; patient-based: 0.84 versus 0.62; both p<0.01). The accuracy of CTA combined with iFRCT was significantly increased compared to CTA alone for vessels with intermediate stenosis (83% versus 40%, p<0.01). CONCLUSION: iFRCT showed better diagnostic performance than CTA. iFRCT may be a promising method for detection of ischaemia-causing coronary stenosis, even in vessels with intermediate stenosis.


Assuntos
Angiografia por Tomografia Computadorizada , Angiografia Coronária , Estenose Coronária/diagnóstico por imagem , Reserva Fracionada de Fluxo Miocárdico , Isquemia Miocárdica/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Estenose Coronária/complicações , Estenose Coronária/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/etiologia
3.
Ann Biomed Eng ; 43(1): 154-67, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25118668

RESUMO

Validation studies are prerequisites for computational fluid dynamics (CFD) simulations to be accepted as part of clinical decision-making. This paper reports on the 2011 edition of the Virtual Intracranial Stenting Challenge. The challenge aimed to assess the reproducibility with which research groups can simulate the velocity field in an intracranial aneurysm, both untreated and treated with five different configurations of high-porosity stents. Particle imaging velocimetry (PIV) measurements were obtained to validate the untreated velocity field. Six participants, totaling three CFD solvers, were provided with surface meshes of the vascular geometry and the deployed stent geometries, and flow rate boundary conditions for all inlets and outlets. As output, they were invited to submit an abstract to the 8th International Interdisciplinary Cerebrovascular Symposium 2011 (ICS'11), outlining their methods and giving their interpretation of the performance of each stent configuration. After the challenge, all CFD solutions were collected and analyzed. To quantitatively analyze the data, we calculated the root-mean-square error (RMSE) over uniformly distributed nodes on a plane slicing the main flow jet along its axis and normalized it with the maximum velocity on the slice of the untreated case (NRMSE). Good agreement was found between CFD and PIV with a NRMSE of 7.28%. Excellent agreement was found between CFD solutions, both untreated and treated. The maximum difference between any two groups (along a line perpendicular to the main flow jet) was 4.0 mm/s, i.e. 4.1% of the maximum velocity of the untreated case, and the average NRMSE was 0.47% (range 0.28-1.03%). In conclusion, given geometry and flow rates, research groups can accurately simulate the velocity field inside an intracranial aneurysm-as assessed by comparison with in vitro measurements-and find excellent agreement on the hemodynamic effect of different stent configurations.


Assuntos
Hidrodinâmica , Aneurisma Intracraniano/fisiopatologia , Modelagem Computacional Específica para o Paciente , Stents , Circulação Cerebrovascular , Simulação por Computador , Hemodinâmica , Humanos , Reprodutibilidade dos Testes
4.
Genet Mol Res ; 10(4): 3385-402, 2011 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-22179997

RESUMO

Anthocyanidin is a group of flavonoid compounds used as a vegetable pigment and plays an important role in flower coloration and environmental adaptations of the Chinese ornamental plant Scutellaria viscidula. We determined the cDNA sequences of phenylalanine ammonia-lyase (SvPAL), flavanone 3-hydroxylase (SvF3H) and dihydroflavonol 4-reductase (SvDFR) genes in S. viscidula. Comparative analysis showed that the protein products of these three genes did not have a transit peptide at their N-terminal portion, which indicated that these enzymes were directly involved in the substrate conversion in the cytoplasmic matrix. Bioinformatic analysis further revealed that Svpal, Svf3h and Svdfr were the members of flavonoid biosynthetic genes with highly conserved motifs. Based on phylogenetic tree analysis, it appears that PAL, F3H or DFR from different plants might have originated from the same ancestor. This study can help to map and regulate the important stages involved in anthocyanidin biosynthesis by genetic engineering to diversify flower color and improve the ornamental value of S. viscidula.


Assuntos
Oxirredutases do Álcool/genética , Antocianinas/genética , Genes de Plantas/genética , Oxigenases de Função Mista/genética , Fenilalanina Amônia-Liase/genética , Scutellaria/genética , Oxirredutases do Álcool/química , Oxirredutases do Álcool/isolamento & purificação , Sequência de Aminoácidos , Antocianinas/biossíntese , Sequência de Bases , Vias Biossintéticas/genética , Clonagem Molecular , Sequência Conservada/genética , DNA Complementar/genética , Evolução Molecular , Oxigenases de Função Mista/química , Oxigenases de Função Mista/isolamento & purificação , Modelos Moleculares , Dados de Sequência Molecular , Fenilalanina Amônia-Liase/química , Fenilalanina Amônia-Liase/isolamento & purificação , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Estrutura Terciária de Proteína , Scutellaria/enzimologia , Alinhamento de Sequência
5.
Transplant Proc ; 42(5): 1830-4, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20620533

RESUMO

We used in situ perfusion and a multiple-organ harvesting technique to collect islets from adult pig pancreata. The tissues were digested with collagenase P followed by purification in a lympholyte discontinuous gradient using a COBE2991 cell separator. The yield and purity of isolated islets were evaluated with a light microscope after dithizone (DTZ) staining. Islet function was assessed using an in vitro insulin release assay. The results showed that before purification 275,000 +/- 20,895 islet equivalents (IEQ) were obtained from 1 digested pancreas. After purification with gradient centrifugation, the islet yield was 230,350 +/- 26,679 IEQ/pancreas. Each gram of the purified pancreatic tissues yielded 2710 +/- 229 IEQ with an average purity of 50.2 +/- 2.0%. The purified islet cells responded to stimulation with high glucose concentrations (16.7 mmol/L), namely, 4.74-fold greater than the insulin secretion with exposure to the basal level of glucose (3.3 mmol/L; P < .001). These results suggested that the established isolation method can be applied to large-scale purification of fully functional islets from pig pancreata.


Assuntos
Ilhotas Pancreáticas/citologia , Animais , Contagem de Células , Separação Celular/métodos , Tamanho Celular , Humanos , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/metabolismo , Transplante das Ilhotas Pancreáticas/estatística & dados numéricos , Tamanho do Órgão , Pâncreas/anatomia & histologia , Pâncreas/citologia , Suínos
6.
Int J Hyperthermia ; 22(6): 491-506, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16971369

RESUMO

PURPOSE: The objective of this research was to reveal the thermal characteristics of microwave ablations in the vicinity of an arterial bifurcation. METHODS: The temperature distribution after microwave heating of a liver-like material in the close proximity of an arterial bifurcation was simulated using the finite element method. Coupled fluid flow and solid heat transfer were taken into consideration and a three-dimensional analysis was performed. An experimentally determined SAR (specific absorption rate) generated by the absorption of microwaves in liver-like material was used in the analysis instead of utilizing electromagnetic calculations. Several different tests of time-controlled ablations with varying distances between the microwave antenna and the bifurcation were performed and detailed temperature distributions near the bifurcation were obtained. RESULTS: The interaction between the recirculation flow in the bifurcation and the heat transfer in the surrounding tissue makes the temperature distribution near the bifurcation complicated. Most importantly, after a period of continuous heating with constant microwave output power, the maximum temperatures caused by the ablation did not always increase with the distance between the antenna and the bifurcation. CONCLUSION: It can be concluded that inadequate ablations can be the result not only from a close proximity between the antenna and the blood vessel, but also from a complicated blood flow in large vessels whose structure causes recirculation flow.


Assuntos
Artérias/anatomia & histologia , Artérias/fisiologia , Hipertermia Induzida/métodos , Micro-Ondas/uso terapêutico , Temperatura Corporal , Simulação por Computador , Análise de Elementos Finitos , Humanos , Hipertermia Induzida/estatística & dados numéricos , Técnicas In Vitro , Fígado/irrigação sanguínea , Circulação Hepática , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/fisiopatologia , Neoplasias Hepáticas/terapia , Matemática , Modelos Anatômicos , Modelos Teóricos , Imagens de Fantasmas
7.
J Med Eng Technol ; 30(5): 310-4, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16980286

RESUMO

In this paper, a 3-channel wavelet transform method is introduced to recover palm print images following serious deformation. The deformation processing is actually a kind of digital re-sampling. A filter bank consisting of three filters is implemented for wavelet decomposition of the palm print image, and then a procedure of binary interpolation is performed after the image is reconstructed by another filter bank consisting of another three filters. The design of multi-channel wavelet filter bank is based on the Quadrature Mirror Filter (QMF) method. Because the noise is caused by the Morie stripe, the images are further de-noised after the geometry deformation is addressed. Acceptable results have been obtained.


Assuntos
Mãos , Processamento de Imagem Assistida por Computador/métodos , Dermatoglifia , Humanos
8.
Australas Phys Eng Sci Med ; 29(2): 196-202, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16845925

RESUMO

In order to simulate the hemodynamic environment of human arteries in vivo, we designed a laminar flow apparatus which can precisely simulate the normal stress and shear stress to which cultured endothelial cells are exposed. Under both normal and abnormal physiological conditions, this apparatus can accurately control and adjust the values of normal stress and shear stress and the frequency of pulse waves, as well as the amplitude of pulsatile flow. This in vitro apparatus provides an experimental platform for studying the response of the biological characteristics of cultured endothelial cells in a hemodynamic environment.


Assuntos
Técnicas de Cultura de Células/instrumentação , Células Endoteliais/citologia , Células Endoteliais/fisiologia , Mecanotransdução Celular/fisiologia , Técnicas Analíticas Microfluídicas/instrumentação , Estimulação Física/instrumentação , Transdutores , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Técnicas de Cultura de Células/métodos , Células Cultivadas , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Técnicas Analíticas Microfluídicas/métodos , Estimulação Física/métodos , Fluxo Pulsátil/fisiologia , Resistência ao Cisalhamento , Estresse Mecânico
9.
Med Eng Phys ; 26(7): 545-52, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15271282

RESUMO

The nonlinear pulsatile blood flow in S-shaped curved arteries was studied with finite element method. Numerical simulations for flows in two models of S-shaped curved arteries with different diameters and under the same boundary conditions were performed. The temporal and spatial distributions of hemodynamic variables during the cardiac cycle such as velocity field, secondary flow, pressure, and wall shear stresses in the arteries were analyzed. Results of numerical simulations showed that the secondary flow in the larger S-shaped curved artery is more complex than that in the smaller one; stronger eddy flow occurred in the inner bends of curved arteries; pressure and wall shear stresses changed violently in the curved arteries, especially in the larger model. These hemodynamic variables in curved arteries will cause important effects on the function of arterial endothelium in the region. For instance, they may lead to the proliferation of smooth muscle cells and the thickening of the intima, and cardiovascular diseases such as atherosclerosis may develop in such regions. Due to having the special blood flow characteristics in the S-shaped arteries, it is worthwhile to study flow in this kind of curved artery. The comprehensive theoretical foundation showed in the present study can be extended to approach problems of nonlinear pulsatile flow in curved arteries with more complex geometrical shape.


Assuntos
Artérias/fisiologia , Modelos Cardiovasculares , Miócitos de Músculo Liso/fisiologia , Fluxo Pulsátil , Animais , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Análise de Elementos Finitos , Hemorreologia , Pressão , Resistência ao Cisalhamento , Estresse Mecânico
10.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 18(4): 583-8, 2001 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-11791314

RESUMO

The blood flows in the ascending aorta and the aortic arch are studied. The theoretical models, boundary conditions and calculation conditions are proposed. The numerical simulation with finite element method of the blood flow in aortic arch of dogs is carried out according to the physiologically pulsatile flow conditions. The calculation results are analyzed with scientific visualization method.


Assuntos
Aorta Torácica/fisiologia , Análise de Elementos Finitos , Modelos Cardiovasculares , Fluxo Pulsátil , Animais , Aorta/fisiologia , Arteriosclerose/fisiopatologia , Simulação por Computador , Cães , Hemodinâmica , Dinâmica não Linear
11.
Hua Xi Yi Ke Da Xue Xue Bao ; 32(4): 587-9, 2001 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-12528557

RESUMO

OBJECTIVE: To investigate the effect of salvia miltiorrhiza and shengmai (SS) on inflammatory mediator and renal function in patients with obstructive jaundice (OJ). METHODS: This study included three groups: the OJ patients receiving SS for 6 days after operation (the SS group, n = 15); the OJ patients not receiving SS (the OJ group, n = 15); the patients with other hepato-biliary disorders (the Non-OJ group, n = 15). The levels of ET, LPs, TNF-alpha, IL-6, IL-8 and urine RBP, TFR, ALB were measured one day before operation and 1, 4, 7 days after operation. RESULTS: The SS group's LPs, TNF-alpha, IL-6, IL-8, ET, RBP, TFR and ALB levels were obviously lower on Day 7 after operation as compared with those on Day 1 after operation (P < 0.05). The urine RBP and ALB levels were significantly lower in the SS group than in the OJ group (P < 0.05). CONCLUSION: The post-operative use of salvia miltiorrhiza and shengmai for patients with obstructive jaundice may effectively decrease the postoperative levels of plasma LPs, ET, TNF-alpha, IL-6 and IL-8. At the same time, salvia miltiorrhiza and shengmai may protect renal function by inhibiting inflammatory mediator and improving blood dynamics.


Assuntos
Colestase/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Fitoterapia , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Idoso , Colestase/fisiopatologia , Colestase/cirurgia , Combinação de Medicamentos , Endotoxinas/sangue , Feminino , Humanos , Interleucina-6/sangue , Interleucina-8/sangue , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Panax , Extratos Vegetais , Salvia miltiorrhiza
12.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 17(1): 95-100, 106, 2000 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-10879204

RESUMO

This paper introduces the importance of studying pulse wave propagation and neviews the development process of the theories of pulse wave propagation. The main research achievements of nonlinear theories of pulse wave propagation are described, and the developing directions of studying pulse wave propagation are briefly stated.


Assuntos
Artérias/fisiologia , Pulso Arterial , Humanos , Matemática , Modelos Biológicos
13.
Hua Xi Yi Ke Da Xue Xue Bao ; 31(3): 402-4, 2000 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-12545846

RESUMO

This study was designed to evaluate the efficacy of traditional Chinese Medicine-X in preventing the necrotic infection of the pancreas in severe acute pancreatitis (SAP). Sixty rats were randomly divided into five groups with 12 rats in each one: (1) normal control, (2) SAP + 0.9% normal saline (1 ml x 100 g-1 x 24 h-1), (3) SAP + gentamycin (2000 u x 100 g-1 x 24 h-1), (4) SAP + TCM-X (1.0 g x 100 g-1 x 24 h-1), and (5) SAP + gentamycin (2000 u x 100 g-1 x 24 h-1) + TCM-X (1.0 g x 100 g-1 x 24 h-1). The medicines were given by way of gastrotube, once every 24 hours, twice in all. Pancreatitis was induced by a single intraperitoneal injection of 500 mg.100 g-1 of L-arginine. Serum endotoxin were observed and the clone forming units from mesenteric lymphnode and pancreas were obtained after 48 hours treatment. 96 hours after the experiment, the bacteria found in the mesenteric lymphnodes and pancreas in groups three, four and five were reduced as compared to that in group two; the levels of serum endotoxin were reduced, too. These data indicate that TCM-X and gentamycin in decontamination by way of gastrotube are effective in preventing bacterial translocation complicated by SAP, and the effect of TCM-X is stronger than that of gentamycin.


Assuntos
Translocação Bacteriana , Medicamentos de Ervas Chinesas/uso terapêutico , Escherichia coli/fisiologia , Pancreatite/tratamento farmacológico , Fitoterapia , Doença Aguda , Animais , Antibacterianos/uso terapêutico , Endotoxinas/sangue , Feminino , Gentamicinas/uso terapêutico , Masculino , Ratos , Ratos Sprague-Dawley
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