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1.
J Med Biochem ; 43(2): 250-256, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38699694

RESUMO

Background: To investigate the expression levels and diagnostic value of glial cell line-derived neurotrophic factor (GDNF), carcinoembryonic antigen (CEA) and carbohydrate antigen199 (CA199) in patients with colorectal carcinoma (CRC). Methods: 50 CRC patients at our hospital from Feb. 2020 to Feb. 2021 were chosen as the malignant group, another 50 patients with benign colonic diseases were chosen as the benign group, and 50 healthy people who came to our hospital for physical examination during the same period were considered as the control group. Fasting peripheral venous blood was taken from all research subjects in the morning and tested by a fully-automated electrochemiluminometer to determine the GDNF, CEA and CA199 levels. The sensitivity and specificity of the combined detection of the three indexes for CRC were analyzed, and the receiver operating characteristic (ROC) curve was plotted to record the area under the curve (AUC). Results: The malignant group had remarkably higher CEA and CA199 levels (P<0.001) and a lower GDNF level (P<0.001) when compared with the benign and control groups. The sensitivity, specificity, positive predictive value and negative predictive value of the combined detection were 96.0%, 94.0%, 88.9% and 97.9%, respectively. Under combined detection, AUC (95% CI) = 0.950 (0.909-0.991), standard error = 0.021, and P<0.001. Conclusions: The combined diagnosis of serum GDNF, CEA and CA199 is a reliable method to improve the diagnostic accuracy of CRC, and this strategy can effectively reduce the missed diagnosis rate and has high application value in clinic.

2.
IEEE Comput Graph Appl ; 37(3): 70-81, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28113833

RESUMO

A color sketch creates a vivid depiction of a scene using sparse pencil strokes and casual colored brush strokes. The interactive drawing system ColorSketch can help novice users generate color sketches from photos. To preserve artistic freedom and expressiveness, the proposed system gives users full control over pencil strokes, while automatically augmenting pencil sketches using color mapping, brush stroke rendering, and blank area creation. Experimental and user study results demonstrate that users, especially novices, can create better color sketches with our system than when using traditional manual tools.

3.
IEEE Trans Med Imaging ; 36(3): 769-780, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28114011

RESUMO

We present a fast enclosure transform (ET) to localize complex objects of interest from speckle imagery. This approach explores the spatial confinement on regional features from a sparse image feature representation. Unrelated, broken ridge features surrounding an object are organized collaboratively, giving rise to the enclosureness of the object. Three enclosure likelihood measures are constructed, consisting of the enclosure force, potential energy, and encloser count. In the transform domain, the local maxima manifest the locations of objects of interest, for which only the intrinsic dimension is known a priori. The discrete ET algorithm is computationally efficient, being on the order of O(MN) using N measuring distances across an image of M ridge pixels. It involves easy and few parameter settings. We demonstrate and assess the performance of ET on the automatic detection of the prostate locations from supra-pubic ultrasound images. ET yields superior results in terms of positive detection rate, accuracy and coverage.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Ultrassonografia/métodos , Feminino , Humanos , Masculino , Mamografia , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem
4.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 34(3): 291-4, 2016 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-27526456

RESUMO

OBJECTIVE: To study the effects of pulsed ultrasound (PUS) and pulsed electromagnetic fields (PEMF) on the secretion of extracellular matrix from a culture complex during in vitro chondrogenesis. METHODS: All the rat bone marrow mesen- chymal stem cell pellets were cultured in achondrogenic medium. Different intensities of PUS (100, 150, and 200 mW · cm⁻²) and PEMF (1, 2, and 5 mT) were applied to the cell pellets for 2 weeks. Group N was cultured without PUS and PEMF stimu- lation as control. The culture medium was collected after 2 weeks of culture. Enzyme-linked immunosorbent assay (ELISA) was used to detect the type of collagen and glycosaminoglycan (GAG) in the culture medium. RESULTS: PUS increased the secreting-type collagen and GAG from cell pellets compared with group N (P < 0.05), whereas there was no difference in different intensities (P > 0.05). PEMF had no significant effect on the secretion of the type of collagen (P > 0.05). A PEMF of 1 mT had no significant effect on the secretion of GAG (P > 0.05). A PEMF 2 and 5 mT decreased the secretion of GAG (P < 0.05). CONCLUSION: To prevent the secretary of extracellular matrix may play a role in chondrogenic effect of PEMF.


Assuntos
Células da Medula Óssea/efeitos da radiação , Condrogênese/efeitos da radiação , Campos Eletromagnéticos , Células-Tronco Mesenquimais/efeitos da radiação , Animais , Células Cultivadas , Matriz Extracelular , Glicosaminoglicanos , Células-Tronco Hematopoéticas , Ratos , Ondas Ultrassônicas
5.
Org Biomol Chem ; 13(37): 9551-8, 2015 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-26288320

RESUMO

New chiral S,N- and S,P-ligands starting from tert-butanesulfinamide were synthesized in four steps, applying Pd-catalyzed asymmetric allylic substitutions of dimethyl 2-fluoromalonate. The induced effect of the Pd/S,N-ligand catalyst on the enantioselectivity depends on the steric demand of the substituent at the o-position of the pyridine ring. This method produced monofluorinated allylation products in up to high yield with high enantioselectivity.


Assuntos
Compostos Alílicos/química , Halogenação , Malonatos/química , Malonatos/síntese química , Paládio/química , Compostos de Sulfônio/química , Catálise , Técnicas de Química Sintética , Ligantes , Estereoisomerismo
6.
PLoS One ; 10(6): e0128978, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26053177

RESUMO

AIMS: We previously demonstrated that resveratrol (RSV) administration causes cardiac stromal cell-derived factor (SDF)-1 upregulation and can enhance the mobilization of stem cells in mice with acute myocardial infarction (AMI). However, the upstream signal transduction involved in SDF-1 regulation in the setting of AMI and RSV administration remains unclear. Because RSV is a sirtuin 1 (SIRT1) activator and SIRT proteins act as deacetylases, we investigated the role of SIRT1 in SDF-1 upregulation and its subsequent effects. METHODS AND RESULTS: In vitro experiments with H9C2 cardiomyocytes under hypoxia and serum-deprivation conditions showed that p53 acted upstream of SDF-1. RSV could not regulate SDF-1 effectively after SIRT1 silencing, indicating that it is dependent on SIRT1. Subsequently, male C57BL/6 mice were divided into four groups: 1) sham, 2) MI, 3) MI+RSV, and 4) MI+RSV plus nicotinamide, an inhibitor of the deacetylase activity of SIRT (MI+RSV+NAM). Compared with the sham mice, AMI caused a slight increase in the cardiac p53 level and resulted in significant SIRT1 downregulation and p53 acetylation or activation. Compared with the MI mice, MI+RSV administration improved the cardiac SDF-1 level and reversed the reduction of SIRT1 and the activation of p53. Furthermore, we observed less cardiac dysfunction in MI+RSV mice and determined that NAM abolished the effects of RSV. CONCLUSIONS: RSV enhances cardiac SDF-1 excretion after AMI partially through a SIRT1 normalization/p53 inactivation pathway.


Assuntos
Quimiocina CXCL12/metabolismo , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Estilbenos/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima/efeitos dos fármacos , Acetilação/efeitos dos fármacos , Animais , Hipóxia Celular/efeitos dos fármacos , Fibrose , Inativação Gênica/efeitos dos fármacos , Testes de Função Cardíaca/efeitos dos fármacos , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Resveratrol , Sirtuína 1/metabolismo , Ultrassonografia
7.
Cogn Neurodyn ; 8(2): 167-75, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24624236

RESUMO

Previous experimental work has shown that the firing rate of multiple time-scales of adaptation for single rat neocortical pyramidal neurons is consistent with fractional-order differentiation, and the fractional-order neuronal models depict the firing rate of neurons more verifiably than other models do. For this reason, the dynamic characteristics of the fractional-order Hindmarsh-Rose (HR) neuronal model were here investigated. The results showed several obvious differences in dynamic characteristic between the fractional-order HR neuronal model and an integer-ordered model. First, the fractional-order HR neuronal model displayed different firing modes (chaotic firing and periodic firing) as the fractional order changed when other parameters remained the same as in the integer-order model. However, only one firing mode is displayed in integer-order models with the same parameters. The fractional order is the key to determining the firing mode. Second, the Hopf bifurcation point of this fractional-order model, from the resting state to periodic firing, was found to be larger than that of the integer-order model. Third, for the state of periodically firing of fractional-order and integer-order HR neuron model, the firing frequency of the fractional-order neuronal model was greater than that of the integer-order model, and when the fractional order of the model decreased, the firing frequency increased.

8.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 5362-4, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17281463

RESUMO

A noninvasive EEG biofeedback system based on virtual reality (VR) environment is developed. The system translates EEG signals into movement and interaction. VR environment provides an ideal medium to represent the spatial and temporal nature of electrical activity emanating from the brain. The VR environment is developed based on MS DirectX technique. SMR-component based biofeedback training in three normal male subjects and two female subjects are reported. The difficulties in biofeedback research and our future research interests are discussed.

9.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 2790-3, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17282821

RESUMO

Non-negative matrix factorization (NMF) is an algorithm that is able to learn a parts-based representation. The paper proposes a new spontaneous EEG classification method for attention-related tasks. NMF was employed as feature extraction tool, which leads to more localized and sparse features than other two reference methods: power spectrum method and principal component analysis. With conventional back propagation neural network classifier, several experiments were carried out. It was showed that the NMF-ANN structure preserved the spatio-temporal characteristics of EEG signals.

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