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1.
Front Pediatr ; 11: 1205384, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37539011

RESUMO

Pediatric-type follicular lymphoma (PTFL) is a rare pediatric-type indolent B-cell lymphoma that clinicopathologically differs from adult lymphoma. Accurate diagnosis of PTFL, which is often challenging, is essential to avoid missed diagnosis, misdiagnosis, and overtreatment. To improve our understanding of PTFL, clinicopathological features, differential diagnosis, and molecular mutation characteristics of four patients of PTFL were analyzed using hematoxylin and eosin staining, immunohistochemistry, polymerase chain reaction, fluorescence in situ hybridization (FISH), and next-generation sequencing (NGS). A relevant literature review was also performed. All four PTFL patients were male, with ages of 6, 18, 13, and 15 years, and had St. Jude stage I or III. Microscopic results showed that the structure of the lymph nodes was destroyed; the tumor follicles were enlarged and irregular; medium-large blastoid cells with a consistent shape were visible in tumor follicles, and the nucleus was round or oval; and the "starry sky" pattern was easily observed. Tumor cells expressed CD20, PAX-5, BCL6, and CD10. None of the tumor cells expressed BCL2, CD3, CD5, MUM1, and CyclinD1. CD21 showed dilated growth of a follicular dendritic cell network in tumor follicles. EBER genes were negative in all cases. FISH testing also showed negative BCL2 gene breaks and IRF4 gene breaks in all cases. NGS detected 12 related mutant genes, including KMT2D, CD79B, GNA13, MYD88, PCLO, TCF3, IRF8, MAP2K1, FOXO1, POLE, INPP5D, and FAT4. Two of the four patients had an IRF8 gene mutation, and one patient had a dual mutation of the MAP2K1 gene. Our study revealed the unique clinicopathological features and molecular mutational characteristics of PTFL, consolidated our understanding of PTFL, and identified other rare mutant genes, which may further contribute to the study of the molecular mechanism and differential diagnosis of PTFL.

3.
PLoS One ; 15(11): e0240663, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33211704

RESUMO

With the rapid development of big data and deep learning, breakthroughs have been made in phonetic and textual research, the two fundamental attributes of language. Language is an essential medium of information exchange in teaching activity. The aim is to promote the transformation of the training mode and content of translation major and the application of the translation service industry in various fields. Based on previous research, the SCN-LSTM (Skip Convolutional Network and Long Short Term Memory) translation model of deep learning neural network is constructed by learning and training the real dataset and the public PTB (Penn Treebank Dataset). The feasibility of the model's performance, translation quality, and adaptability in practical teaching is analyzed to provide a theoretical basis for the research and application of the SCN-LSTM translation model in English teaching. The results show that the capability of the neural network for translation teaching is nearly one times higher than that of the traditional N-tuple translation model, and the fusion model performs much better than the single model, translation quality, and teaching effect. To be specific, the accuracy of the SCN-LSTM translation model based on deep learning neural network is 95.21%, the degree of translation confusion is reduced by 39.21% compared with that of the LSTM (Long Short Term Memory) model, and the adaptability is 0.4 times that of the N-tuple model. With the highest level of satisfaction in practical teaching evaluation, the SCN-LSTM translation model has achieved a favorable effect on the translation teaching of the English major. In summary, the performance and quality of the translation model are improved significantly by learning the language characteristics in translations by teachers and students, providing ideas for applying machine translation in professional translation teaching.


Assuntos
Ensino , Algoritmos , Big Data , Aprendizado Profundo , Humanos , Redes Neurais de Computação
4.
Carbohydr Polym ; 183: 230-239, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29352879

RESUMO

The aim of the present study was to investigate structural characteristic and in vitro fermentation of a novel polysaccharide named ST-P2 from Sargassum thunbergii by human fecal inoculums, and its impact on human colonic microbiota. The results showed that ST-P2 was homogeneous with molecular weight of 48,788 Da, and consisted of arabinose, galactose, glucose, xylose, and mannose. The main linkage types were identified as (1 → 5)-α-L-Araf, (1 → 3)-α-L-Manp, (1 → 3,6)-ß-D-Galp, (1 → 6)-α-D-Glcp, and (1 → 3)-ß-D-Xylp, respectively. After 48 h fermentation, 67.83 ±â€¯1.15% of total carbohydrate was utilized by colonic microbiota. The pH value in the fecal culture significantly decreased from 6.09 ±â€¯0.11 to 4.70 ±â€¯0.04. The concentrations of total short chain fatty acids, acetic, propionic, n-butyric and n-valeric acids significantly increased compared to the blank. ST-P2 could remarkably modulate the composition and abundance of beneficial microbiota. These results suggest that ST-P2 could potentially be a functional food aimed at promoting the gut health.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Polissacarídeos/química , Sargassum/química , Fermentação , Humanos , Polissacarídeos/farmacologia , Sargassum/crescimento & desenvolvimento , Sargassum/metabolismo
5.
Carbohydr Polym ; 173: 192-201, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28732858

RESUMO

In the present work, optimization of microwave-assisted extraction of polysaccharides from Sargassum thunbergii was investigated. The physicochemical properties, structural characteristics, and in vitro antioxidant and hypoglycemic activities were determined. The optimal extraction conditions with a yield of 2.84±0.09% for extraction of polysaccharides (STP-1) were extraction time 23min, microwave power 547W, extraction temperature 80°C, and the ratio of raw material to water 1:27g/mL. STP-1 contained 32.7% of total carbohydrate, 1.86% of protein, and 15.2% of sulfates. STP-1 had a major molecular weight of 190.4kDa, and comprised of arabinose, galactose, glucose, xylose, mannose, galacturonic acid, and glucuronic acid with molar percentages of 1.94, 30.7, 4.54, 23.2, 17.6, 8.11, and 13.9%, respectively. In addition, STP-1 showed strong antioxidant and α-glucosidase inhibitory activities, and could improve the glucose uptake in insulin-resistant HepG2 cells, suggesting that STP-1 can be exploited as a promising natural antioxidant and hypoglycemic agent.

6.
Artigo em Inglês | MEDLINE | ID: mdl-25832559

RESUMO

A survey of 2-acetyl-4-tetrahydroxybutylimidazole (THI) and 4-methylimidazole (4-MeI) concentrations in caramel colours, vinegar and beverages from the Chinese market were performed by ultrahigh-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). In total, 117 samples, 78 caramel colour samples, 23 vinegar samples and 16 beverage samples, were investigated. The results indicated that 4-MeI was found in all samples. THI was found in a part of the samples and also the level range was lower compared to 4-MeI. In caramel colour samples, the concentration level range of THI was 1.0-74.3 mg/kg and of 4-MeI was 1.5-1291.8 mg/kg. In vinegar samples, the concentration level range of THI was 13.3-119.2 µg/L and for 4-MeI 111.2-2077.8 µg/L. In beverage samples, THI was only found in two samples and the concentration level range of 4-MeI was 10.8-307.1 µg/L. THI and 4-MeI levels in vinegar and beverages were rather low compared with those in caramel colour samples. These observations can be helpful for evaluating individual exposure to THI and 4-MeI from caramel colours, vinegar and beverages in China.


Assuntos
Bebidas/análise , Carboidratos/química , Carcinógenos/análise , Condimentos/análise , Contaminação de Alimentos , Imidazóis/análise , Ácido Acético/química , Ácido Acético/economia , Ácido Acético/normas , Bebidas/economia , Bebidas/normas , Carboidratos/normas , China , Cromatografia Líquida de Alta Pressão , Condimentos/economia , Condimentos/normas , Inspeção de Alimentos/métodos , Guias como Assunto , Limite de Detecção , Reação de Maillard , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
7.
Life Sci ; 110(2): 70-6, 2014 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-25014676

RESUMO

AIMS: Upregulation of heme oxygenase (HO)-1 plays an important role in vascular protection. Valsartan attenuates neointimal hyperplasia in animal studies. The objective of this study was to examine the role of HO-1 and angiotensin II type 1 (AT1) receptor in the action of valsartan on neointimal hyperplasia in balloon-injured rat aortic arteries. MAIN METHODS: Thirty-six male Wistar rats were randomly divided into the following three groups with twelve rats in each group: control group, surgery (model) group, and valsartan group. Aortic balloon injury was performed to elicit endothelial denudation with a 2F balloon catheter. On days 14 and 28 after injury, blood was harvested to measure bilirubin levels. Aortic arteries were harvested for morphometry analysis, to determine angiotensin II (Ang II) level, and to analyze mRNA or protein expression. KEY FINDINGS: Compared with the control group, proliferation and intimal thickening of vascular smooth muscle cells (VSMCs) were obvious in the surgery group rats on days 14 and 28 after injury. Valsartan significantly reduced the proliferation and intimal thickening. Additionally, pretreatment with valsartan significantly reduced Ang II levels, AT1 receptor, and p38 mitogen-activated protein kinase (MAPK) expression. Valsartan increased HO-1 protein and mRNA expression, as well as increased serum bilirubin levels compared with the surgery group. SIGNIFICANCE: Valsartan treatment decreased neointimal hyperplasia in balloon-injured rats. The mechanism of action might be linked to the upregulation of HO-1, downregulation of AT1 receptor and inhibition of p38MAPK signal pathway.


Assuntos
Aorta Torácica/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/metabolismo , Hiperplasia/patologia , Neointima/patologia , Receptor Tipo 1 de Angiotensina/metabolismo , Tetrazóis/farmacologia , Valina/análogos & derivados , Análise de Variância , Angioplastia Coronária com Balão/efeitos adversos , Animais , Aorta Torácica/efeitos dos fármacos , Bilirrubina/sangue , Primers do DNA/genética , Hiperplasia/tratamento farmacológico , Masculino , Neointima/tratamento farmacológico , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tetrazóis/uso terapêutico , Valina/farmacologia , Valina/uso terapêutico , Valsartana
8.
J Geriatr Cardiol ; 10(2): 151-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23888175

RESUMO

OBJECTIVE: To investigate the effects and mechanisms of rosuvastatin on angiotensin -converting enzyme 2 (ACE2) in the process of neointimal formation after vascular balloon injury in rats, and to explore the effects of ACE2 and rosuvastatin in restenosis. METHODS: Thirty-six Wistar rats were randomly allocated into three groups: control group (n = 12), surgery group (n = 12), and statin group (n = 12). Aortic endothelial denudation of rats was performed using 2F balloon catheters. At days 14 and 28 after injury, aortic arteries were harvested to examine the following. Intimal thickening was examined by hematoxylin and eosin staining. We measured angiotensin II (Ang II) and angiotensin 1-7 (Ang-[1-7]) levels by a radioimmunological method or enzyme-linked immunosorbent assay. Protein and mRNA expression of ACE2 and Ang II type 1 receptor (AT1) were investigated by immunohistochemistry, Western blots, and Reverse transcriptase-polymerase chain reaction (RT-PCR). We measured changes in proliferating cell nuclear antigen (PCNA) by immunohistochemistry. The level of phosphorylated extracellular signal regulated kinase 1/2 (P-ERK1/2) was evaluated by Western blotting. RESULTS: Proliferation of vascular smooth muscle cells (VSMC) and intimal thickening were higher at day 14 after vascular balloon injury in the surgery group compared with the control group. Proliferation of VSMC was decreased by day 28 after injury, while intimal thickening continued. With rosuvastatin treatment, the extent of VSMC proliferation and intimal thickening was reduced at day 14 and 28 after injury. Ang II and P-ERK levels were significantly increased, Ang-(1-7) levels were significantly decreased, mRNA and protein expressions of ACE2 were significantly decreased, and AT1 expression was significantly increased at days 14 and 28 after vascular balloon injury in the surgery group compared with the control group. PCNA expression was higher in the surgery group than in the control group, and it was significantly decreased after being given rosuvastatin. Expression of ACE2 mRNA and protein, and Ang-(1-7) levels were significantly increased, while AT1 expression and levels of Ang II and P-ERK were significantly decreased in the statin group compared with the surgery group. CONCLUSIONS: Expression of ACE2 mRNA and protein is decreased in the process of intimal thickening after balloon injury. The inhibitory effect of rosuvastatin on intimal thickening is related to upregulation of ACE2, an increase in Ang-(1-7), downregulation of AT1, and activation of the P-ERK pathway.

9.
Zhonghua Xin Xue Guan Bing Za Zhi ; 40(8): 697-701, 2012 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-23141017

RESUMO

OBJECTIVE: To investigate the process and mechanism of neointimal formation, the level of angiotensin II and angiotensin (1-7), the expression of angiotensin converting enzyme 2(ACE2), angiotensin II type 1 receptor (AT(1)R), extracellular signal regulated kinase (ERK) and the effects of valsartan on them after aortic balloon injury in rats. METHODS: Aortic endothelial denudation of rats was induced by 2F balloon catheter. Thirty-six rats were randomly allocated into three groups: Group 1 (n = 12): controls; Group 2 (n = 12): aortic balloon injury; Group 3 (n = 12): valsartan (20 mg×kg(-1)×d(-1)) given from 1 day before injury to 14 and 28 days after aortic injury. The expression of ACE2 and AT1, the level of P-ERK, AngII, Ang(1-7) and intimal thickening were investigated by RT-PCR technique, immunohistochemistry, Western blot, radioimmunological method, enzyme linked immunosorbent assay (ELISA) and HE stain, respectively. RESULTS: (1) The proliferation of vascular smooth muscle cells (VSMC) and the intimal thickening were evidenced at day 14 and 28 after aortic balloon injury. (2) The mRNA and protein expressions of ACE2 decreased significantly, but AT(1)R mRNA and protein expression increased significantly at day 14 and 28 after balloon injury. (3) The level of AngII and p-ERK increased and Ang(1-7) reduced after balloon injury. (4) Valsartan not only attenuated the proliferation of VSMC and the intimal thickening but also upregulated the expression of ACE2 and the level of Ang(1-7) and downregulated the expression of AT(1)R and the level of AngII, p-ERK in this model. CONCLUSION: Intimal thickening after balloon injury is linked with reduced expression of ACE2.Valsartan can inhibit the intimal thickening possibly by upregulating ACE2 and Ang(1-7) and downregulating AT(1) in this model.


Assuntos
Músculo Liso Vascular/metabolismo , Peptidil Dipeptidase A/metabolismo , Tetrazóis/farmacologia , Valina/análogos & derivados , Angiotensina I/metabolismo , Enzima de Conversão de Angiotensina 2 , Animais , Balão Intra-Aórtico , Masculino , Músculo Liso Vascular/efeitos dos fármacos , Fragmentos de Peptídeos/metabolismo , Ratos , Ratos Wistar , Receptor Tipo 1 de Angiotensina/metabolismo , Valina/farmacologia , Valsartana
10.
IEEE Trans Neural Netw ; 21(8): 1339-45, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20601313

RESUMO

In this brief, adaptive neural control is presented for a class of output feedback nonlinear systems in the presence of unknown functions. The unknown functions are handled via on-line neural network (NN) control using only output measurements. A barrier Lyapunov function (BLF) is introduced to address two open and challenging problems in the neuro-control area: 1) for any initial compact set, how to determine a priori the compact superset, on which NN approximation is valid; and 2) how to ensure that the arguments of the unknown functions remain within the specified compact superset. By ensuring boundedness of the BLF, we actively constrain the argument of the unknown functions to remain within a compact superset such that the NN approximation conditions hold. The semiglobal boundedness of all closed-loop signals is ensured, and the tracking error converges to a neighborhood of zero. Simulation results demonstrate the effectiveness of the proposed approach.


Assuntos
Adaptação Fisiológica/fisiologia , Algoritmos , Inteligência Artificial , Retroalimentação , Redes Neurais de Computação , Dinâmica não Linear , Animais , Artefatos , Humanos , Processamento de Sinais Assistido por Computador
11.
IEEE Trans Neural Netw ; 20(7): 1148-64, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19482574

RESUMO

In this paper, adaptive variable structure neural control is investigated for a class of nonlinear systems under the effects of time-varying state delays and uncertain hysteresis inputs. The unknown time-varying delay uncertainties are compensated for using appropriate Lyapunov-Krasovskii functionals in the design, and the effect of the uncertain hysteresis with the Prandtl-Ishlinskii (PI) model representation is also mitigated using the proposed control. By utilizing the integral-type Lyapunov function, the closed-loop control system is proved to be semiglobally uniformly ultimately bounded (SGUUB). Extensive simulation results demonstrate the effectiveness of the proposed approach.


Assuntos
Algoritmos , Inteligência Artificial , Simulação por Computador , Redes Neurais de Computação , Dinâmica não Linear , Robótica/métodos , Software/tendências , Fatores de Tempo
12.
IEEE Trans Syst Man Cybern B Cybern ; 39(2): 431-43, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19095551

RESUMO

In this paper, adaptive neural control is investigated for a class of unknown nonlinear systems in pure-feedback form with the generalized Prandtl-Ishlinskii hysteresis input. To deal with the nonaffine problem in face of the nonsmooth characteristics of hysteresis, the mean-value theorem is applied successively, first to the functions in the pure-feedback plant, and then to the hysteresis input function. Unknown uncertainties are compensated for using the function approximation capability of neural networks. The unknown virtual control directions are dealt with by Nussbaum functions. By utilizing Lyapunov synthesis, the closed-loop control system is proved to be semiglobally uniformly ultimately bounded, and the tracking error converges to a small neighborhood of zero. Simulation results are provided to illustrate the performance of the proposed approach.

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