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1.
Front Physiol ; 15: 1362386, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38651048

RESUMO

Accurate image segmentation plays a crucial role in computer vision and medical image analysis. In this study, we developed a novel uncertainty guided deep learning strategy (UGLS) to enhance the performance of an existing neural network (i.e., U-Net) in segmenting multiple objects of interest from images with varying modalities. In the developed UGLS, a boundary uncertainty map was introduced for each object based on its coarse segmentation (obtained by the U-Net) and then combined with input images for the fine segmentation of the objects. We validated the developed method by segmenting optic cup (OC) regions from color fundus images and left and right lung regions from Xray images. Experiments on public fundus and Xray image datasets showed that the developed method achieved a average Dice Score (DS) of 0.8791 and a sensitivity (SEN) of 0.8858 for the OC segmentation, and 0.9605, 0.9607, 0.9621, and 0.9668 for the left and right lung segmentation, respectively. Our method significantly improved the segmentation performance of the U-Net, making it comparable or superior to five sophisticated networks (i.e., AU-Net, BiO-Net, AS-Net, Swin-Unet, and TransUNet).

2.
Artif Intell Med ; 148: 102757, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38325920

RESUMO

Semi-supervised segmentation plays an important role in computer vision and medical image analysis and can alleviate the burden of acquiring abundant expert-annotated images. In this paper, we developed a residual-driven semi-supervised segmentation method (termed RDMT) based on the classical mean teacher (MT) framework by introducing a novel model-level residual perturbation and an exponential Dice (eDice) loss. The introduced perturbation was integrated into the exponential moving average (EMA) scheme to enhance the performance of the MT, while the eDice loss was used to improve the detection sensitivity of a given network to object boundaries. We validated the developed method by applying it to segment 3D Left Atrium (LA) and 2D optic cup (OC) from the public LASC and REFUGE datasets based on the V-Net and U-Net, respectively. Extensive experiments demonstrated that the developed method achieved the average Dice score of 0.8776 and 0.7751, when trained on 10% and 20% labeled images, respectively for the LA and OC regions depicted on the LASC and REFUGE datasets. It significantly outperformed the MT and can compete with several existing semi-supervised segmentation methods (i.e., HCMT, UAMT, DTC and SASS).

3.
Onco Targets Ther ; 14: 157-164, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33447057

RESUMO

BACKGROUND: Long noncoding RNAs (lncRNA) exert essential functions during tumorigenesis. However, how lncRNAs participate in glioma development remains poorly researched. This study aimed to determine how DDX11-AS1 affects glioma progression. METHODS: Gene expression was analyzed by qRT-PCR. Survival rate curve was plotted in 56 glioma patients. Loss-of-function assays were performed to analyze proliferation, migration, and invasion through CCK8, colony formation, and transwell assays. Luciferase assay and RNA pulldown assays were conducted to illustrate the underlying molecular mechanism. RESULTS: DDX11-AS1 expression was upregulated in glioma tissues and cells. DDX11-AS1 overexpression was linked with poor prognostic value. DDX11-AS1 knockdown suppressed proliferation, migration, and invasion while inducing apoptosis. DDX11-AS1 interacted with miR-499b-5p to eliminate it, leading to upregulation of RWDD4 expression. RWDD4 was upregulated in glioma while miR-499b-5p was downregulated. CONCLUSION: DDX11-AS1 upregulation promotes glioma progression through acting as a competing endogenous RNA for miR-499b-5p to upregulate RWDD4.

4.
Clin Exp Pharmacol Physiol ; 45(3): 226-233, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29047147

RESUMO

Epilepsy is a common complex neurological disorder, and some forms are resistant to drug treatment. The HCN1/HCN2 genes encode hyperpolarization-activated cyclic nucleotide-gated channels, which play important roles in the electrophysiology of neurons. We investigated the association between HCN1/HCN2 variants and drug resistance or the risk of genetic generalized epilepsies (GGEs). We used matrix-assisted laser desorption/ionization time-of-flight mass spectrometry to assess nine variants of HCN1/HCN2 in 284 healthy participants and 483 GGEs (279 drug-responsive, 204 drug-resistant). Frequencies of HCN2 rs7255568 and rs3752158 G alleles differed in GGEs and in controls (P = .039, P = .027, respectively). The frequency of HCN2 haplotype (CAC) was higher in patients than controls (P = .046). The frequency of the HCN1 rs10462087 CC+CT genotype was lower in patients with childhood absence epilepsy (CAE) than controls (P = .047). Rs7255568 was associated with the risk of CAE (P = .028) and juvenile myoclonic epilepsy (JME) (P = .02). Rs3752158 was associated with the risk of generalized tonic-clonic seizures, JME, and febrile seizures (all P < .05). The frequency of the HCN2 haplotype (CAC) was higher in patients with JME (P = .015) and in those with febrile seizures (P = .024) than in controls. No significant association was found between HCN1/HCN2 alleles, genotypes or haplotypes, and drug resistance in patients. After Bonferroni's multiple comparisons correction, only the HCN2 rs3752158 C allele and GC+CC genotype frequencies in patients with JME were higher than those in controls (19.2% vs 11.6%, odds ratio (OR) = 1.71, 95% CI = 1.18-2.32), P = .004 < 0.05/9; 36% vs 22.2%, OR = 1.62(1.18-2.23), P = .003 < 0.05/9). Our study suggests that HCN2 rs3752158 is involved in the susceptibility to JME.


Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsia Generalizada/genética , Predisposição Genética para Doença , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Polimorfismo de Nucleotídeo Único , Canais de Potássio/metabolismo , Estudos de Casos e Controles , Resistência a Medicamentos/genética , Epilepsia Generalizada/tratamento farmacológico , Feminino , Genótipo , Humanos , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Masculino , Canais de Potássio/genética
5.
DNA Cell Biol ; 36(10): 853-861, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28817313

RESUMO

Chemokine receptor 7 (CCR7) has emerged as an inducer of invasion, migration, and epithelial-mesenchymal transition (EMT) in cancer. In this research, human malignant glioma cells were stimulated with transforming growth factor beta 1 (TGF-ß1) and siCCR7. The data show that CCR7 mediates TGF-ß1-induced EMT, migration, and invasion in U251 and U87 cells and that these effects of TGF-ß1 were reversed by treatment with siCCR7 or a CCR7 neutralizing antibody. Importantly, the TGF-ß1-mediated increase in nuclear factor kappaB (NF-κB) activity in human glioma cells was reduced by treatment with siCCR7 or a CCR7 neutralizing antibody. Furthermore, CCR7 was shown to mediate TGF-ß1-induced glioma cancer cell migration by activating matrix metalloproteinase 2 (MMP2)/9. Our results indicate that CCR7 mediates TGF-ß1-induced MMP2/9 expression through NF-κB signaling, thus facilitating glioma cell migration, invasion, and EMT, all of which progressively increase with glioblastoma progression. These findings indicate that CCR7 is a potential therapeutic target for malignant glioma.


Assuntos
Movimento Celular/fisiologia , Transição Epitelial-Mesenquimal , Glioblastoma/metabolismo , Glioma/metabolismo , Receptores CCR7/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/fisiologia , Humanos , Neoplasias Pulmonares/patologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo
6.
Acta Otolaryngol ; 137(6): 567-571, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28084876

RESUMO

CONCLUSION: To make a comprehensive analysis with a variety of diagnostic maneuvers is conducive to the correct diagnosis and classification of BPPV. OBJECTIVE: Based on the standard spatial coordinate-based semicircular canal model for theoretical observation on diagnostic maneuvers for benign paroxysmal positional vertigo (BPPV) to analyze the meaning and key point of each step of the maneuver. MATERIALS AND METHODS: This study started by building a standard model of semicircular canal with space orientation by segmentation of the inner ear done with the 3D Slicer software based on MRI scans, then gives a demonstration and observation of BPPV diagnostic maneuvers by using the model. RESULTS: The supine roll maneuver is mainly for diagnosis of lateral semicircular canal BPPV. The Modified Dix-Hallpike maneuver is more specific for the diagnosis of posterior semicircular canal BPPV. The side-lying bow maneuver designed here is theoretically suitable for diagnosis of anterior semicircular canal BPPV.


Assuntos
Vertigem Posicional Paroxística Benigna/diagnóstico , Exame Físico/métodos , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Modelos Biológicos , Estudos Retrospectivos
7.
Zhonghua Nan Ke Xue ; 19(4): 321-3, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23678710

RESUMO

OBJECTIVE: To assess the long-term effect and safety of non-occlusive intra-vas device (IVD) for male contraception in comparison with no-scalpel vasectomy (NSV). METHODS: We conducted a follow-up investigation on 100 males who had received IVD and another 50 who had undergone NSV 6 years before. We compared the rates of sperm absence and complications between the two groups. RESULTS: Follow-up visits were successfully performed on 95 males (95%) of the IVD group and 44 (88%) of the NSV group. Pregnancy was not found in any of the cases. Spermatozoa (> or = 5 x 10(6)/ml) were not detected in 87 cases (91.58%) in the IVD group and in 44 cases (95.45%) in the NSV group, with no significant differences between the two groups (P > 0.05). The rate of postoperative complications in the IVD group (11.58%) showed no significant difference from that of the NSV group (4.55%) (P > 0.05). CONCLUSION: IVD is as effective and safe as NSV for male contraception.


Assuntos
Anticoncepção/métodos , Ducto Deferente , Adulto , Seguimentos , Humanos , Masculino , Vasectomia
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