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1.
IEEE Trans Med Imaging ; 42(12): 3590-3601, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37432809

RESUMO

Computed tomography (CT) images are the most commonly used radiographic imaging modality for detecting and diagnosing lumbar diseases. Despite many outstanding advances, computer-aided diagnosis (CAD) of lumbar disc disease remains challenging due to the complexity of pathological abnormalities and poor discrimination between different lesions. Therefore, we propose a Collaborative Multi-Metadata Fusion classification network (CMMF-Net) to address these challenges. The network consists of a feature selection model and a classification model. We propose a novel Multi-scale Feature Fusion (MFF) module that can improve the edge learning ability of the network region of interest (ROI) by fusing features of different scales and dimensions. We also propose a new loss function to improve the convergence of the network to the internal and external edges of the intervertebral disc. Subsequently, we use the ROI bounding box from the feature selection model to crop the original image and calculate the distance features matrix. We then concatenate the cropped CT images, multiscale fusion features, and distance feature matrices and input them into the classification network. Next, the model outputs the classification results and the class activation map (CAM). Finally, the CAM of the original image size is returned to the feature selection network during the upsampling process to achieve collaborative model training. Extensive experiments demonstrate the effectiveness of our method. The model achieved 91.32% accuracy in the lumbar spine disease classification task. In the labelled lumbar disc segmentation task, the Dice coefficient reaches 94.39%. The classification accuracy in the Lung Image Database Consortium and Image Database Resource Initiative (LIDC-IDRI) reaches 91.82%.


Assuntos
Deslocamento do Disco Intervertebral , Humanos , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Metadados , Diagnóstico por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Pulmão , Processamento de Imagem Assistida por Computador/métodos
2.
BMC Sports Sci Med Rehabil ; 15(1): 88, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37464427

RESUMO

BACKGROUND: Chronic ankle instability (CAI) is a form of musculoskeletal disease that can occur after a lateral ankle sprain, and it is characterized by pain, recurrent ankle sprains, a feeling of "giving way" at the ankle joint, and sensorimotor deficits. There has been increasing evidence to suggest that plastic changes in the brain after the initial injury play an important role in CAI. As one modality to treat CAI, whole-body vibration (WBV) has been found to be beneficial for treating the sensorimotor deficits accompanying CAI, but whether these benefits are associated with brain plasticity remains unknown. Therefore, the current study aims to investigate the effect of WBV on sensorimotor deficits and determine its correlation with plastic changes in the brain. METHODS: The present study is a single-blind randomized controlled trial. A total of 80 participants with CAI recruited from the university and local communities will be divided into 4 groups: whole-body vibration and balance training (WBVBT), balance training (BT), whole-body vibration (WBV), and control group. Participants will be given the WBV intervention (25-38 Hz, 1.3-2 mm, 3-time per week, 6-week) supervised by a professional therapist. Primary outcome measures are sensorimotor function including strength, balance, proprioception and functional performance. Brain plasticity will be evaluated by corticomotor excitability, inhibition, and representation of muscles, as measured by transcranial magnetic stimulation. Activation of brain areas will be assessed through functional near-infrared spectroscopy. Secondary outcome measures are self-reported functional outcomes involving the Cumberland Ankle Instability Tool and the Foot and Ankle Ability Measure. All tests will be conducted before and after the WBV intervention, and at 2-week follow-up. Per­protocol and intention-to-treat analysis will be applied if any participants withdraw. DISCUSSION: This is the first trial to investigate the role of brain plasticity in sensorimotor changes brought by WBV for individuals with CAI. As plastic changes in the brain have been an increasingly important aspect in CAI, the results of the current study can provide insight into the treatment of CAI from the perspective of brain plasticity. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR2300068972); registered on 02 March 2023.

3.
Med Image Anal ; 81: 102567, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35994969

RESUMO

The automatic segmentation of lumbar anatomy is a fundamental problem for the diagnosis and treatment of lumbar disease. The recent development of deep learning techniques has led to remarkable progress in this task, including the possible segmentation of nerve roots, intervertebral discs, and dural sac in a single step. Despite these advances, lumbar anatomy segmentation remains a challenging problem due to the weak contrast and noise of input images, as well as the variability of intensities and size in lumbar structures across different subjects. To overcome these challenges, we propose a coarse-to-fine deep neural network framework for lumbar anatomy segmentation, which obtains a more accurate segmentation using two strategies. First, a progressive refinement process is employed to correct low-confidence regions by enhancing the feature representation in these regions. Second, a grayscale self-adjusting network (GSA-Net) is proposed to optimize the distribution of intensities dynamically. Experiments on datasets comprised of 3D computed tomography (CT) and magnetic resonance (MR) images show the advantage of our method over current segmentation approaches and its potential for diagnosing and lumbar disease treatment.


Assuntos
Disco Intervertebral , Imageamento por Ressonância Magnética , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Redes Neurais de Computação
4.
Food Res Int ; 156: 111339, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35651087

RESUMO

Milk-derived peptides have been identified as the essential ingredients in the food industry for the health-promoting properties. Some bioactive peptides in the milk product can be released by the specific protease system of lactic acid bacteria (LAB) during the fermentation processing. In this research, the bioactive peptides released from the casein and whey protein are investigated by the hydrolyzing ability of the Lactobacillus brevis CGMCC15954, Lactobacillus reuteri WQ-Y1 and Lactobacillus plantarum A3. Results found that the hydrolysates of casein/whey protein generated by L. reuteri WQ-Y1 have the potential antioxidant activity. Furthermore, milk-derived peptides identified by the liquid chromatography-mass spectrometry (LC-MS/MS) with the BIOPEP-UWM database showed the YLGYLEQLLR (αS1-casein), VKEAMAPK (ß-casein), YIPIQYVLSR (κ-casein) fragment had the promising antioxidant activity, especially VKEAMAPK, which exhibited IC50 of 0.63 and 0.86 mg/mL in DPPH and ABTS free radical scavenging activity. The finding of this study sheds some light of obtaining milk-derived peptides by using the Lactobacillus strains and proves the potential bioactive function of the LAB fermented milk products.


Assuntos
Antioxidantes , Proteínas do Leite , Antioxidantes/química , Caseínas/química , Cromatografia Líquida , Lactobacillus/metabolismo , Proteínas do Leite/análise , Peptídeos/química , Espectrometria de Massas em Tandem , Proteínas do Soro do Leite/análise
5.
Anal Chem ; 92(5): 4101-4107, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32037810

RESUMO

Depression is immensely attributed to the overactivation of N-methyl-d-aspartic acid (NMDA) receptor in the brains. As regulatory binding partners of NMDA receptor, both Zn2+ and H+ are intimately interrelated to NMDA receptor's activity. Therefore, exploring synergistic changes on the levels of Zn2+ and H+ in brains will promote the knowledge and treatment of depression. However, the lack of efficient, appropriate imaging tools limits simultaneously tracking Zn2+ and H+ in living mouse brains. Thus, a well-designed dual-color fluorescent probe (DNP) was fabricated for the simultaneous monitoring of Zn2+ and H+ in the brains of mice with depression. Encountering Zn2+, the probe evoked bright blue fluorescence at 460 nm. Meanwhile, the red fluorescence at 680 nm was decreased with H+ addition. With blue/red dual fluorescence signal of DNP, we observed the synchronous increased Zn2+ and H+ in PC12 cells under oxidative stress. Notably, in vivo imaging for the first time revealed the simultaneous reduction of Zn2+ and pH in brains of mice with depression-like behaviors. Further results implied that the NMDA receptor might be responsible for the coinstantaneous fluctuation of Zn2+ and H+ during depression. Altogether, this work is conducive to the knowledge of neural signal transduction mechanisms, advancing our understanding of the pathogenesis in depression.


Assuntos
Encéfalo/metabolismo , Depressão/patologia , Corantes Fluorescentes/química , Hidrogênio/metabolismo , Microscopia Confocal/métodos , Receptores de N-Metil-D-Aspartato/metabolismo , Zinco/metabolismo , Animais , Corticosterona/uso terapêutico , Depressão/tratamento farmacológico , Depressão/metabolismo , Modelos Animais de Doenças , Corantes Fluorescentes/síntese química , Concentração de Íons de Hidrogênio , Íons/química , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo , Células PC12 , Ratos
6.
Metab Eng ; 48: 13-24, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29753069

RESUMO

Microbial processes can produce a wide range of compounds; however, producing complex and long chain hydrocarbons remains a challenge. Aldol condensation offers a direct route to synthesize these challenging chemistries and can be catalyzed by microbes using aldolases. Deoxyribose-5-phosphate aldolase (DERA) condenses aldehydes and/or ketones to ß-hydroxyaldehydes, which can be further converted to value-added chemicals such as a precursor to cholesterol-lowering drugs. Here, we implement a short, aldolase-based pathway in Escherichia coli to produce (R)-1,3-BDO from glucose, an essential component of pharmaceutical products and cosmetics. First, we expressed a three step heterologous pathway from pyruvate to produce 0.3 g/L of (R)-1,3-BDO with a yield of 11.2 mg/g of glucose in wild-type E. coli K12 MG1655. We used a systems metabolic engineering approach to improve (R)-1,3-BDO titer and yield by: 1) identifying and reducing major by-products: ethanol, acetoin, and 2,3-butanediol; 2) increasing pathway flux through DERA to reduce accumulation of toxic acetaldehyde. We then implemented a two-stage fermentation process to improve (R)-1,3-BDO titer by 8-fold to 2.4 g/L and yield by 5-fold to 56 mg/g of glucose (11% of maximum theoretical yield) in strain BD24, by controlling pH to 7 and higher dissolved oxygen level. Furthermore, this study highlights the potential of the aldolase chemistry to synthesize diverse products directly from renewable resources in microbes.


Assuntos
Butileno Glicóis/metabolismo , Escherichia coli K12 , Proteínas de Escherichia coli , Frutose-Bifosfato Aldolase , Engenharia Metabólica , Escherichia coli K12/enzimologia , Escherichia coli K12/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Frutose-Bifosfato Aldolase/genética , Frutose-Bifosfato Aldolase/metabolismo
7.
Sci Rep ; 6: 38725, 2016 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-27924940

RESUMO

Quorum-sensing (QS) systems exist universally in bacteria to regulate multiple biological functions. Klebsiella pneumoniae, an industrially important bacterium that produces bio-based chemicals such as 2,3-butanediol and acetoin, can secrete a furanosyl borate diester (AI-2) as the signalling molecule mediating a QS system, which plays a key regulatory role in the biosynthesis of secondary metabolites. In this study, the molecular regulation and metabolic functions of a QS system in K. pneumoniae were investigated. The results showed that after the disruption of AI-2-mediated QS by the knockout of luxS, the production of acetoin, ethanol and acetic acid were relatively lower in the K. pneumoniae mutant than in the wild type bacteria. However, 2,3-butanediol production was increased by 23.8% and reached 54.93 g/L. The observed enhancement may be attributed to the improvement of the catalytic activity of 2,3-butanediol dehydrogenase (BDH) in transforming acetoin to 2,3-butanediol. This possibility is consistent with the RT-PCR-verified increase in the transcriptional level of budC, which encodes BDH. These results also demonstrated that the physiological metabolism of K. pneumoniae was adversely affected by a QS system. This effect was reversed through the addition of synthetic AI-2. This study provides the basis for a QS-modulated metabolic engineering study of K. pneumoniae.


Assuntos
Acetoína/metabolismo , Boratos/metabolismo , Compostos Bicíclicos Heterocíclicos com Pontes/metabolismo , Butileno Glicóis/metabolismo , Klebsiella pneumoniae/metabolismo , Percepção de Quorum/fisiologia
8.
Am J Chin Med ; 40(3): 643-56, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22745076

RESUMO

The mechanism of action of Prunella vulgaris L. (PV) affecting cell migration and invasion of human liver cancer cells remains unknown. In this work we showed that the aqueous extract of PV affected migration and invasion of human liver carcinoma cells by inhibiting activities of metalloproteases, MMP-2 and MMP-9, without affecting cell viabilities. We further showed that PV suppressed migration through attenuation of enzymatic activities of MMP-9 and MMP-2 at transcriptional levels and the effects can be correlated with the status of p53 in hepatocarcinoma cells. This work provides a new dimension of understanding on Prunella vulgaris in restraining migration and invasion in human liver cancer cells.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Metaloproteinases da Matriz/metabolismo , Fitoterapia , Prunella , Antineoplásicos Fitogênicos/farmacologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Proteína Supressora de Tumor p53/metabolismo
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