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1.
JMIR Mhealth Uhealth ; 9(9): e24402, 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34473067

RESUMO

BACKGROUND: For rehabilitation training systems, it is essential to automatically record and recognize exercises, especially when more than one type of exercise is performed without a predefined sequence. Most motion recognition methods are based on feature engineering and machine learning algorithms. Time-domain and frequency-domain features are extracted from original time series data collected by sensor nodes. For high-dimensional data, feature selection plays an important role in improving the performance of motion recognition. Existing feature selection methods can be categorized into filter and wrapper methods. Wrapper methods usually achieve better performance than filter methods; however, in most cases, they are computationally intensive, and the feature subset obtained is usually optimized only for the specific learning algorithm. OBJECTIVE: This study aimed to provide a feature selection method for motion recognition of upper-limb exercises and improve the recognition performance. METHODS: Motion data from 5 types of upper-limb exercises performed by 21 participants were collected by a customized inertial measurement unit (IMU) node. A total of 60 time-domain and frequency-domain features were extracted from the original sensor data. A hybrid feature selection method by combining filter and wrapper methods (FESCOM) was proposed to eliminate irrelevant features for motion recognition of upper-limb exercises. In the filter stage, candidate features were first selected from the original feature set according to the significance for motion recognition. In the wrapper stage, k-nearest neighbors (kNN), Naïve Bayes (NB), and random forest (RF) were evaluated as the wrapping components to further refine the features from the candidate feature set. The performance of the proposed FESCOM method was verified using experiments on motion recognition of upper-limb exercises and compared with the traditional wrapper method. RESULTS: Using kNN, NB, and RF as the wrapping components, the classification error rates of the proposed FESCOM method were 1.7%, 8.9%, and 7.4%, respectively, and the feature selection time in each iteration was 13 seconds, 71 seconds, and 541 seconds, respectively. CONCLUSIONS: The experimental results demonstrated that, in the case of 5 motion types performed by 21 healthy participants, the proposed FESCOM method using kNN and NB as the wrapping components achieved better recognition performance than the traditional wrapper method. The FESCOM method dramatically reduces the search time in the feature selection process. The results also demonstrated that the optimal number of features depends on the classifier. This approach serves to improve feature selection and classification algorithm selection for upper-limb motion recognition based on wearable sensor data, which can be extended to motion recognition of more motion types and participants.

2.
BMC Complement Med Ther ; 21(1): 23, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413354

RESUMO

BACKGROUND: Evidence showed that Tai Chi may have beneficial effects among hypertensive individuals, although the results are not convincing. We aim to conduct a high-quality clinical trial with 24-h BP measurement to provide robust evidence of Tai Chi for essential hypertension. METHODS: This is an open-label single-center randomized controlled trial with 3 parallel arms. We will compare Tai Chi with walking and waiting-list control. We will recruit 234 hypertensive patients with mild to moderate essential hypertension and randomly assign them to 3 different groups. Participants in Tai Chi group will receive a group-format Yang style 24-form Tai Chi exercise program, 3 sessions per week for 12 weeks. The walking group will be asked to walk, 3 sessions per week for 12 weeks. The waiting-list group will not receive any interventions and/or exercise training. The primary outcome is the change in average 24-h systolic blood pressure (SBP) between baseline and 12 weeks after randomization. The secondary outcomes include 24-h Diastolic Blood Pressure (DBP), average SBP and average DBP during the daytime and night-time, blood pressure (BP) variability, SBP load and DBP load, circadian rhythm of BP, and morning BP surge, endothelial functional indicators, home measured BP, quality of life, adverse events and so on. DISCUSSION: We expect findings of this trial will provide important insight into application of Tai Chi as an effective and acceptable method for hypertensive patients. Successful completion of this proposed study will also contribute to promotion of Tai Chi in the community in the future. TRIAL REGISTRATION: Clinicaltrials.gov registry: https://clinicaltrials.gov/ct2/show/NCT04267471 , date: February 12, 2020.


Assuntos
Hipertensão Essencial/terapia , Tai Ji , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Humanos , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Caminhada
3.
Am J Mens Health ; 14(2): 1557988320916402, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32321348

RESUMO

This study aimed to report a rare case of intermittent azoospermia and ring-like small supernumerary marker chromosomes (sSMCs). An infertile man was diagnosed with azoospermia presenting a normal male phenotype with complete masculinization. Karyotyping and polymerase chain reaction (PCR) were used to detect 16 sequence-tagged sites on the AZF subregions of the Y chromosome, and 115 candidate genes were screened for mutations. Mutations included single nucleotide variations, insertions, and deletions. Metaphase chromosomes were studied by standard trypsin-Giemsa banding; fluorescent in situ hybridization and PCR were performed to analyze specific Y chromosome regions; gene mutations were detected. Chromosomal analysis detected 117 metaphase cells; a mosaicism with marker 1 and marker 2 sSMCs in 2 metaphase cells (47, X, +mar1x2 karyotype), a mosaicism with marker 2 sSMCs in 14 metaphase cells (46, X, +mar2 karyotype), and a mosaicism with marker 1 sSMCs in 76 metaphase cells (46, X, +mar1 karyotype), coexisting with a 45,X cell line in the remaining 25 metaphase cells. PCR analysis showed the sY160 heterochromosome on the AZFc subregion was absent. Next-generation sequencing identified an asthenozoospermia-specific mutation in GAPDHS (rs2293681), and Sanger sequencing verified this mutation. This gene encodes a protein belonging to the glyceraldehyde-3-phosphate dehydrogenase family of enzymes that play an important role in carbohydrate metabolism. Like its somatic cell counterpart, this sperm-specific enzyme functions in a nicotinamide adenine dinucleotide-dependent manner to remove hydrogen and add phosphate to glyceraldehyde 3-phosphate to form 1,3-diphosphoglycerate. During spermiogenesis, this enzyme may play an important role in regulating the switch between different energy-producing pathways, and it is required for sperm motility and male fertility. A mosaic 46, X, +mar1[76]/45, X[25]/46, X, +mar2[14]/47, X, +mar1x2[2] karyotype could be the main explanation for the azoospermia/severe oligospermia, while the likely pathogenic GAPDHS intron mutation may contribute to the symptom of immotile sperms detected in the semen analysis.


Assuntos
Azoospermia/genética , Cromossomos Humanos Y/genética , Mutação/genética , Adulto , Andrologia , China , Humanos , Infertilidade/genética , Cariotipagem/métodos , Masculino
4.
Acta Diabetol ; 49(1): 47-55, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21327982

RESUMO

Increase in vascular permeability is the most important pathological event during the development of diabetic retinopathy. Deposition of advanced glycation end products (AGEs) plays a crucial role in the process of diabetes. This study was to investigate the role of moesin and its underlying signal transduction in retinal vascular hyper-permeability induced by AGE-modified mouse serum albumin (AGE-MSA). Female C57BL/6 mice were used to produce an AGE-treated model by intraperitoneal administration of AGE-MSA for seven consecutive days. The inner blood-retinal barrier was quantified by Evans blue leakage assay. Endothelial F-actin cytoskeleton in retinal vasculature was visualized by fluorescence probe staining. The expression and phosphorylation of moesin in retinal vessels were detected by RT-PCR and western blotting. Further studies were performed to explore the effects of Rho kinase (ROCK) and p38 MAPK pathway on the involvement of moesin in AGE-induced retinal vascular hyper-permeability response. Treatment with AGE-MSA significantly increased the permeability of the retinal microvessels and induced the disorganization of F-actin in retinal vascular endothelial cells. The threonine (T558) phosphorylation of moesin in retinal vessels was enhanced remarkably after AGE administration. The phosphorylation of moesin was attenuated by inhibitions of ROCK and p38 MAPK, while this treatment also prevented the dysfunction of inner blood-retinal barrier and the reorganization of F-actin in retinal vascular endothelial cells. These results demonstrate that moesin is involved in AGE-induced retinal vascular endothelial dysfunction and the phosphorylation of moesin is triggered via ROCK and p38 MAPK activation.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Produtos Finais de Glicação Avançada/farmacologia , Proteínas dos Microfilamentos/metabolismo , Proteínas Quinases/metabolismo , Retina/efeitos dos fármacos , Vasos Retinianos/efeitos dos fármacos , Animais , Permeabilidade Capilar/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Ativação Enzimática/efeitos dos fármacos , Feminino , Produtos Finais de Glicação Avançada/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Retina/metabolismo , Vasos Retinianos/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologia , Quinases Associadas a rho/metabolismo , Quinases Associadas a rho/fisiologia
5.
Sensors (Basel) ; 11(4): 3527-44, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22163809

RESUMO

This paper is focused on the study of the energy hole problem in the Progressive Multi-hop Rotational Clustered (PMRC)-structure, a highly scalable wireless sensor network (WSN) architecture. Based on an analysis on the traffic load distribution in PMRC-based WSNs, we propose a novel load-similar node distribution strategy combined with the Minimum Overlapping Layers (MOL) scheme to address the energy hole problem in PMRC-based WSNs. In this strategy, sensor nodes are deployed in the network area according to the load distribution. That is, more nodes shall be deployed in the range where the average load is higher, and then the loads among different areas in the sensor network tend to be balanced. Simulation results demonstrate that the load-similar node distribution strategy prolongs network lifetime and reduces the average packet latency in comparison with existing nonuniform node distribution and uniform node distribution strategies. Note that, besides the PMRC structure, the analysis model and the proposed load-similar node distribution strategy are also applicable to other multi-hop WSN structures.


Assuntos
Redes de Comunicação de Computadores/instrumentação , Tecnologia sem Fio , Algoritmos , Simulação por Computador , Modelos Teóricos
6.
Brain Res ; 1373: 1-10, 2011 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-21167822

RESUMO

Advanced glycation end products (AGEs) have been found to play an important role in the development of diabetes, and AGE levels are correlated with the severity of diabetic complications. We have demonstrated that moesin, a protein linker between actin filaments and the plasma membrane, undergoes phosphorylation of its threonine 558 residue by AGE stimulation in human dermal microvascular endothelial cells through activation of p38 and Rho kinase (ROCK) pathways. In this study, we observed in situ whether AGEs caused phosphorylation of vascular endothelial cells in the brains of AGE-stimulated mice. The animals were injected with AGE-modified mouse serum albumin (AGE-MSA) for 7 consecutive days. Immunohistochemistry was conducted to assess the phosphorylation of moesin in brain vessels. The level of moesin protein phosphorylation was also assessed in cerebral microvessels by western blotting. The effects of p38 and ROCK activation were determined by application of a p38 inhibitor (SB203580) and a ROCK inhibitor (Y27632) at 30 min before each AGE administration. The results showed specific expression of moesin in murine brain vascular endothelial cells. AGE treatment induced a significant increase of threonine 558 phosphorylation in moesin, while inhibition of p38 and ROCK remarkably attenuated the phosphorylation of moesin. The level of moesin protein phosphorylation was also increased in cerebral microvessels, along with an increased permeability of the blood-brain barrier, while inhibition of the p38 and ROCK attenuated these responses. These results demonstrate that AGEs cause the phosphorylation of moesin in murine brain microvascular endothelial cells, with p38 and ROCK being involved in this process.


Assuntos
Encéfalo/anatomia & histologia , Endotélio/efeitos dos fármacos , Produtos Finais de Glicação Avançada/farmacologia , Proteínas dos Microfilamentos/metabolismo , Amidas/farmacologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiologia , Interações Medicamentosas/fisiologia , Células Endoteliais/efeitos dos fármacos , Endotélio/citologia , Inibidores Enzimáticos/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Imidazóis/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Piridinas/farmacologia , Treonina/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Quinases Associadas a rho/metabolismo
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