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1.
Bone Rep ; 19: 101711, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37681002

RESUMO

Objective: Osteoporosis is the most common skeletal disease in humans. Early onset of osteoporosis is usually asymptomatic, so early diagnosis is critical. The purpose of this study was to analyze the value of MRI-based VBQ scores for evaluating osteoporosis. Methods: We searched PubMed, Embase, the Cochrane Library databases, Web of Science, and some Chinese electronic databases for published articles and the ClinicalTrials.gov site for completed but unpublished studies on evaluating the value of MRI-based VBQ scores for evaluating osteoporosis. We calculated the summarized sensitivity, specificity, the ROC curve (AUC) values and their 95% confidence intervals (CIs) using MetaDiSc 1.4 software and STATA. Results: Our study included 8 studies involving 999 patients of which 660 patients were diagnosed with osteopenia/osteoporosis, and 339 patients were identified as having normal BMD. The pooled sensitivity was 0.809 (95% CI, 0.777-0.838, I2 = 78.8%), the pooled specificity was 0.640 (95% CI, 0.587-0.691, I2 = 85.9%), and the pooled AUC was 0.8375. Conclusion: MRI-based VBQ scores provided high sensitivity and moderate specificity in detecting osteoporosis. Opportunistic use of VBQ scores could be considered, e.g. before lumbar spine surgery. Prospero registration number: CRD42022377024.

2.
Med Phys ; 48(12): 7930-7945, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34658035

RESUMO

PURPOSE: To create a network which fully utilizes multi-sequence MRI and compares favorably with manual human contouring. METHODS: We retrospectively collected 89 MRI studies of the pelvic cavity from patients with prostate cancer and cervical cancer. The dataset contained 89 samples from 87 patients with a total of 84 valid samples. MRI was performed with T1-weighted (T1), T2-weighted (T2), and Enhanced Dixon T1-weighted (T1DIXONC) sequences. There were two cohorts. The training cohort contained 55 samples and the testing cohort contained 29 samples. The MRI images in the training cohort contained contouring data from radiotherapist α. The MRI images in the testing cohort contained contouring data from radiotherapist α and contouring data from another radiotherapist: radiotherapist ß. The training cohort was used to optimize the convolution neural networks, which included the attention mechanism through the proposed activation module and the blended module into multiple MRI sequences, to perform autodelineation. The testing cohort was used to assess the networks' autodelineation performance. The contoured organs at risk (OAR) were the anal canal, bladder, rectum, femoral head (L), and femoral head (R). RESULTS: We compared our proposed network with UNet and FuseUNet using our dataset. When T1 was the main sequence, we input three sequences to segment five organs and evaluated the results using four metrics: the DSC (Dice similarity coefficient), the JSC (Jaccard similarity coefficient), the ASD (average mean distance), and the 95% HD (robust Hausdorff distance). The proposed network achieved improved results compared with the baselines among all metrics. The DSC were 0.834±0.029, 0.818±0.037, and 0.808±0.050 for our proposed network, FuseUNet, and UNet, respectively. The 95% HD were 7.256±2.748 mm, 8.404±3.297 mm, and 8.951±4.798 mm for our proposed network, FuseUNet, and UNet, respectively. Our proposed network also had superior performance on the JSC and ASD coefficients. CONCLUSION: Our proposed activation module and blended module significantly improved the performance of FuseUNet for multi-sequence MRI segmentation. Our proposed network integrated multiple MRI sequences efficiently and autosegmented OAR rapidly and accurately. We also discovered that three-sequence fusion (T1-T1DIXONC-T2) was superior to two-sequence fusion (T1-T2 and T1-T1DIXONC, respectively). We infer that the more MRI sequences fused, the better the automatic segmentation results.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Humanos , Masculino , Redes Neurais de Computação , Pelve/diagnóstico por imagem , Estudos Retrospectivos
3.
Acad Pediatr ; 21(1): 63-69, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32112865

RESUMO

BACKGROUND: This study aimed to examine individual and combined associations between after-school sedentary time (ST) and daily physical activity (PA) with executive function development in children. METHODS: The study included 4304 children aged 6 to 12 years. ST and PA were assessed using the International Physical Activity Questionnaire Short Form, and executive function was assessed using the Behavior Rating Inventory of Executive Function (Parent Version). Participants were classified as low (<2 h per day) or high (≥2 h per day) ST and low (not meeting guidelines) or high (meeting guidelines) PA. Resulting groups were defined as 1) low ST/high PA, 2) low ST/low PA, 3) high ST/high PA, and 4) high ST/low PA. RESULTS: Children in group 4 had the highest mean T-scores for BRIEF indices (48.23 ± 8.44, indicating increased symptoms of executive function dysfunction), followed by those in group 3 (47.10 ± 8.05), group 2 (45.81 ± 7.78), and group 1 (44.41 ± 7.31). ST was positively related to the T-score of all indices, independent of moderate-to-vigorous physical activity (MVPA). Significantly negative associations were observed between MVPA and Metacognition Index only in the high ST subgroup. CONCLUSIONS: Low ST and high PA were positively associated with executive function development in children. Notably, children with high ST and high PA demonstrated more significant deficits in executive function than those with low ST and low PA, suggesting that intervention efforts should focus on ST reduction in addition to promoting PA.


Assuntos
Função Executiva , Comportamento Sedentário , Acelerometria , Criança , Estudos Transversais , Exercício Físico , Humanos , Pais , Instituições Acadêmicas
4.
Front Public Health ; 9: 736424, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35096728

RESUMO

Aims: Little information exists on the associations of cardiovascular health, a new metric proposed by the American Heart Association, and executive function, particularly in children. We aimed to explore this topic. Methods: We studied 3,798 children aged 6-12 years from 5 schools in Guangzhou, China. The executive function of children was evaluated using parent reports of the Behavioral Rating Inventory of Executive Function, which included 2 composite indexes and 8 subscale scores. We calculated the number of ideal cardiovascular health (range: 0-7) based on smoking, body mass index, physical activity (PA), diet, blood pressure, cholesterol, and glucose. A generalized linear mixed model was used to assess the association of the number of ideal cardiovascular health metrics and executive function. Results: Compared with children exhibiting 1-3 ideal cardiovascular health metrics, decreases of 1.37-2.63 points (indicating better performance) in metacognition index and its 5 subscale indexes (initiate, working memory, plan/organize, organization of materials, and monitor) were observed in children who attained 5 or 6-7 ideal metrics (all p for trend <0.001). Ideal diet and ideal PA were independently associated with lower indexes of behavioral regulation and metacognition. Conclusions: The number of ideal cardiovascular health was positively associated with performance of executive function in children.


Assuntos
Função Executiva , Povo Asiático , Criança , China/epidemiologia , Humanos , Instituições Acadêmicas , Estados Unidos
5.
Child Obes ; 16(8): 554-563, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33185475

RESUMO

Background: The relationship of physical activity (PA) to cardiorespiratory fitness (CRF) is well established in children. However, the extent to which adiposity affects this association remains unclear. Objective: The study aimed to explore whether the relationships of different PA intensities to CRF are explained by adiposity. Methods: Cross-sectional data were collected from 374 children (51.87% boys) aged 7-12 years. The time spent (min/day) in vigorous PA (VPA), moderate PA (MPA), light PA (LPA), and sedentary behavior was objectively measured using triaxial accelerometry. Height, weight, and waist circumference (WC) were objectively measured, from which the BMI was derived. The 20-meter shuttle run test was conducted to estimate maximal oxygen consumption [VO2max, mL/(kg·min)]. Linear mixed models and mediation analysis with bootstrapping were used to analyze data. Results: VO2max was positively associated with VPA [ß = 0.143, 95% confidence interval (95% CI): 0.091 to 0.194], MPA (ß = 0.051, 95% CI: 0.016 to 0.086), and moderate-to-vigorous PA (MVPA) (ß = 0.052, 95% CI: 0.029 to 0.075), but not LPA or sedentary time. Both BMI and WC partially mediated the relationships of VPA and MVPA to VO2max, with the percentage of the total effect mediated by adiposity ranging from 18.0% to 19.6%. Similar results were also observed among boys but not among girls. Conclusions: Only moderate or vigorous intensity of PA is favorably correlated with CRF in children. BMI and WC play a pivotal mediating role in these associations, especially in boys, suggesting that promoting higher intensity of PA might benefit children's CRF through reducing adiposity.


Assuntos
Aptidão Cardiorrespiratória , Obesidade Infantil , Acelerometria , Adiposidade , Índice de Massa Corporal , Criança , Estudos Transversais , Exercício Físico , Feminino , Humanos , Masculino , Obesidade Infantil/epidemiologia , Obesidade Infantil/prevenção & controle , Aptidão Física
6.
Int J Hyg Environ Health ; 229: 113583, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32917369

RESUMO

BACKGROUND: Evidence on the associations between particulate matter (PM) and nitrogen dioxide (NO2) exposure with executive function in children is scarce in developing countries. Moreover, few studies investigated ozone (O3) and sulfur dioxide (SO2). This study aimed to investigate the associations between long-term exposure to air pollution and executive function in Chinese children. METHODS: In 2017, we randomly recruited 5028 children aged 6-12 years from 5 schools in Guangzhou city, southern China. Each of 5028 children's executive function were assessed using parent filled questionnaire. We further randomly selected 522 children to take computerized tests to assess working memory, inhibitory control, and cognitive flexibility. The 1-year average residence-based exposure to PM with diameters ≤2.5 (PM2.5) or 10 µm (PM10), NO2, O3, and SO2 exposures were estimated by using an inverse-distance weighting approach. Associations were evaluated by mixed linear regression models. RESULTS: The 1-year average concentrations of PM2.5, PM10, NO2, SO2, and O3 was 39.06 ± 1.12 µg/m3, 60.95 ± 3.49 µg/m3, 53.64 ± 4.44 µg/m3, 12.33 ± 0.79 µg/m3, and 90.07 ± 7.96 µg/m3, respectively. Each interquartile range increment in PM2.5 was associated with 48.04 ms [95% confidence interval (CI): 2.18 to 93.89] increase in inhibitory control and 0.72 (95% CI: -1.14 to -0.29) points decrease in forward recall. PM10 exposure was associated with 0.55 (95% CI: -1.04 to -0.06) and 0.67 points (95% CI: -1.09 to -0.25) reduction in forward and backward recall, respectively. SO2 exposure was associated with 0.69 (95%CI: 0.37 to 1.02) and 0.73 (95%CI: 0.40 to 1.05) high scores of behavioral regulation index and metacognition index, respectively. Significant association was found between O3 exposure and metacognition index (estimate, 95%CI: 0.87, 0.45 to 1.29). No associations for cognitive flexibility were observed. Stratified analyses did not yield any significant modification effects of sex, physical activity, screen time, and parental smoking. CONCLUSIONS: Long-term exposures to PM2.5, PM10, SO2, and O3 were associated with poorer performance in working memory, inhibitory control, behavioral regulation, and metacognition in children.


Assuntos
Poluição do Ar/efeitos adversos , Cognição , Exposição Ambiental/efeitos adversos , Função Executiva , Memória de Curto Prazo , Poluentes Atmosféricos/efeitos adversos , Criança , Pré-Escolar , China , Feminino , Humanos , Masculino , Dióxido de Nitrogênio/efeitos adversos , Ozônio/efeitos adversos , Material Particulado/efeitos adversos , Dióxido de Enxofre/efeitos adversos
7.
Artigo em Inglês | MEDLINE | ID: mdl-32784949

RESUMO

Background: Time spent in different intensity-specific physical activities is codependent, but the substitution effect of different activities on weight status changes in children remains unclear. This study aims to investigate the prospective association between reallocating time in different intensities of physical activity and weight status changes among Chinese children. Methods: A national sample of 15,100 normal-weight children aged 7-18 years (46.7% boys) were recruited in September 2013 and followed up for nine months. Vigorous-intensity physical activity (VPA), moderate-intensity physical activity (MPA), walking, and sedentary time were obtained by International Physical Activity Questionnaire Short Form (IPAQ-SF). Height and weight were objectively measured, by which body mass index (BMI) and BMI z-score were calculated. Weight status was classified by the Chinese criteria for 7- to 18-year-old children. Isotemporal substitution analyses (including single-factor model, partition model, and isotemporal substitution model) were applied to examine the association of time allocation with weight status changes. Results: Each 30 min/day of increase in VPA was favorably associated with a 13.2% reduced risk of incident overweight/obesity in a single-factor model and a 15.6% reduced risk in a partition model. Negative associations were found between VPA, MPA, walking and the risk of being underweight in the single-factor model, but not in the partition model. In substitution models, replacing 30 min/day sedentary time with an equal amount of VPA was favorably associated with a 16.1% reduction of the risk of being overweight/obese. Conclusion: These findings highlight the need for promoting vigorous-intensity physical activity in children.


Assuntos
Acelerometria , Peso Corporal , Exercício Físico , Comportamento Sedentário , Adolescente , Índice de Massa Corporal , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Estudos Prospectivos
8.
J Hypertens ; 38(11): 2215-2222, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32649627

RESUMO

OBJECTIVES: To assess the associations between long-term air pollution exposure and blood pressure in children, and to explore the modifying effects of diet on prehypertension and hypertension. METHODS: We evaluated 7225 primary school children aged 6-12 years from Guangzhou, China, in 2017. The blood pressure was measured objectively. The individual 1-year average concentration of particles with an aerodynamic diameter of 2.5 µm or less or 10 µm or less (PM2.5, PM10), sulfur dioxide (SO2), and ozone (O3) before each blood pressure measurement were calculated by inverse distance weighting interpolation according to each home address. Generalized linear mixed-effects models were used to examine the health effects and potential effect modifications by diet factors after adjusting for covariates. RESULTS: The results showed that the estimated increase in mean SBP was 0.92 mmHg (95% CI 0.05-1.79) per interquartile range increase in O3. An interquartile range increase in the 1-year mean of SO2 and O3 was associated with odds ratios of 1.26 (95% CI 1.04-1.52) and 1.20 (95% CI 1.06-1.35) for prehypertension, respectively. In addition, an interquartile range increase in PM2.5, SO2, and O3 exposure was positively associated with hypertension, with odds ratios of 1.33 (95% CI 1.11-1.61), 1.70 (95% CI 1.33-2.16), and 1.48 (95% CI 1.20-1.83), respectively. Stronger effect estimates between PM2.5, SO2, and O3 concentration on prehypertension were exhibited among subgroups of children with a higher intake of sugar-sweetened beverages. CONCLUSION: Long-term exposure to PM2.5, SO2, and O3 were associated with higher blood pressure levels in children, and dietary intake might modify these associations.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Pressão Sanguínea/fisiologia , Dieta/estatística & dados numéricos , Criança , China , Humanos , Hipertensão , Exposição por Inalação/análise , Exposição por Inalação/estatística & dados numéricos , Pré-Hipertensão
9.
J Clin Sleep Med ; 16(8): 1285-1293, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32279704

RESUMO

STUDY OBJECTIVES: Although weekend catch-up sleep is common among children, the association between weekend catch-up sleep and executive functions remains unclear. We aimed to determine whether weekend catch-up sleep was related to executive functions in school-aged children. METHODS: We analyzed data for 4,699 children (9.00 years ± 1.73 years old, 52.9% boys) from 5 primary schools in Guangzhou, China. Executive functions performance was examined by the Behavior Rating Inventory of Executive Function Parent Form. Validated self-report questionnaires were used to assess sleep status, socioeconomic status, and health behaviors. Multiple linear regression analyses were used to assess the association of weekend catch-up sleep duration with executive functions. RESULTS: Weekday sleep was negatively associated with scores on three composite indices (Behavioral Regulation Index, Metacognition Index, Global Executive Composite), while weekend catch-up sleep was positively associated with them. Children with < 9 hours weekday sleep duration had higher scores in all indices, and there was no correlation between weekend catch-up sleep and scores of all indices (P > .05). For children who slept ≥ 9 hours on weekdays, weekend catch-up sleep of more than 1 hour was associated with increased scores of Behavioral Regulation Index, Metacognition Index, and Global Executive Composite (P < .05). There was no interaction between sex, age, and weekend catch-up sleep and executive functions (P > .05). CONCLUSIONS: Weekend catch-up sleep could not restore the executive functions deficits related to short weekday sleep. Weekend catch-up sleep over 1 hour may have adverse effects on executive functions in school-aged children. CLINICAL TRIAL REGISTRATION: Registry: ClinicalTrials.gov; Title: Prospective Cohort Study on Cognition and Cardiovascular Disease of Sedentary Behaviors in Children; URL: https://clinicaltrials.gov/ct2/show/NCT03582709; Identifier: NCT03582709.


Assuntos
Função Executiva , Sono , Criança , China , Feminino , Humanos , Masculino , Estudos Prospectivos , Instituições Acadêmicas
10.
Artigo em Inglês | MEDLINE | ID: mdl-32121663

RESUMO

Childhood asthma and obesity have posed a parallel epidemic over the past few decades. However, whether asthma diagnosis is associated with obesity, and what the roles of lifestyle factors play in this relationship, remained unclarified. This study aimed to investigate the association between asthma and weight status in Chinese children and explore the potential mediating and/or modifying roles of lifestyle factors in the association. In this cross-sectional study, 16,837 children aged 6-12 years were recruited from Guangzhou, China. Participants' information on physician-diagnosed asthma was collected from parents, and data on physical activity, screen time, and sleeping were reported in a validated questionnaire. Height and weight were objectively measured, and weight status was classified by body mass index (BMI). Multiple logistic regression analysis and mediation analysis were used. Results showed that asthmatic children were at significantly higher risk of obesity (odds ratio (OR) 1.51, 95% confidence interval (CI) 1.03, 2.21) compared with non-asthmatic children. More importantly, this increased risk was even greater in children with moderate-to-vigorous physical activity <60 min/d and children with screen time >2 h/d (both Pinteraction < 0.05). Also, a positive relationship of asthma with overweight was found in children with screen time >2 h/d (OR 3.92, 95% CI 1.56, 9.88), while a negative association was observed between asthma and underweight in children aged 9-12 years (OR 0.23, 95% CI 0.06, 0.92). Mediation analysis indicated that these associations were not mediated by physical activity, screen time, or sleeping. The findings suggested that physician-diagnosed asthma was associated with higher risks of overweight and obesity, and these risks might be exacerbated by insufficient physical activity and prolonged screen time.


Assuntos
Asma , Sobrepeso , Obesidade Infantil , Asma/complicações , Asma/diagnóstico , Índice de Massa Corporal , Criança , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Estilo de Vida , Masculino , Sobrepeso/complicações , Sobrepeso/epidemiologia , Obesidade Infantil/complicações , Obesidade Infantil/epidemiologia
11.
Accid Anal Prev ; 136: 105435, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31935600

RESUMO

This paper proposes an approach to rationally set automated vehicles' car following behavior that explicitly balances between the competing considerations of safety (i.e. small probabilities of a high-consequence crash) and efficiency (guaranteed but small impacts on journey arrival time due to the choice of car following distance). The specification of safety and efficiency are both based on empirically supported concepts and data. In numerical analyses with empirical vehicle trajectories at two sites, we demonstrate intuitive response to systematic variation in numerical values selected as inputs, as well as whether the scope of the efficiency consideration is selfish or systemwide. The proposed balancing is aligned with the standard "Hand Rule" criterion to demonstrate that a duty of care has been met, in which a burden must be borne if it is less than the product of the probability of loss to a third party and the magnitude of loss. Thus the proposed approach is intended to be useful for designers of control algorithms for AVs to establish that they have met their duty of care, taking both safety and efficiency into account.


Assuntos
Acidentes de Trânsito/prevenção & controle , Condução de Veículo , Algoritmos , Automóveis/classificação , Humanos , Segurança
12.
BMJ Open ; 9(10): e030322, 2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31676650

RESUMO

INTRODUCTION: Although studies showed that physical activity (PA) and sedentary behaviour (SB) were associated with cardiometabolic risk factors and cognitive function, both independent and combined associations among them are inconsistent. Cardiometabolic risk factors are also associated with cognitive function, but research of children is limited. Additionally, the brain level mechanisms have not been fully established. The proposed study aims to explore the associations and mechanisms of PA and SB on cognitive function and cardiometabolic risk factors in children. METHODS AND ANALYSIS: This is a school-based prospective cohort study. A total of 8324 participants of this study are primary school students aged 7-12 years old who are followed up every 2 years from January 2017 to December 2026. We used a stratified cluster random sampling to select five primary schools in Guangzhou, China. There are three phases at baseline. At phase I, we collect PA, SB and cognitive function by questionnaires and also conduct anthropometric and biochemical measurements in all participants. At phase II, PA, SB and cognitive function are measured respectively by accelerometers and cognitive tasks among participants randomly selected from four subgroups with different SB and PA levels. At phase III, event-related potentials are recorded using electroencephalogram during a cognitive task among participants randomly selected from phase II. We plan to follow-up all participants until they graduate from high school. The process applied at baseline and follow-up are approximately identical. ETHICS AND DISSEMINATION: Procedures described in this manuscript have been approved by the Ethical Review Committee for Biomedical Research, School of Public Health, Sun Yat-sen University (L2016-010). All parents or guardians of participants signed the informed consent form voluntarily before participating in the study. The findings of the study will be published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT03582709.


Assuntos
Doenças Cardiovasculares/epidemiologia , Cognição , Dislipidemias/epidemiologia , Exercício Físico , Comportamento Sedentário , Acelerometria , Glicemia/metabolismo , Doenças Cardiovasculares/sangue , Criança , Colesterol/sangue , Estudos de Coortes , Dislipidemias/sangue , Eletroencefalografia , Potenciais Evocados , Feminino , Transtornos do Metabolismo de Glucose/epidemiologia , Transtornos do Metabolismo de Glucose/metabolismo , Humanos , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Obesidade/epidemiologia , Estudos Prospectivos , Fatores de Risco , Triglicerídeos/sangue
13.
Chinese Journal of School Health ; (12): 1791-1795, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-815585

RESUMO

Objective@#To investigate the different patterns of 24-h movement behaviors, and their associations with sociodemographic factors in a nationally representative sample of Chinese children aged 6-13 years.@*Methods@#This study was based on a national multi-centered cluster intervention study involving 31 362 children aged 6-13 years from 7 provinces in China. Questionnaires were used to collect moderate to vigorous physical activity (MVPA), screen time (ST) and sleep duration, as well as sociodemographic variables including age, gender, area of residence, parents’ education level and family income. Generalized linear mixed model (GLMM) analyses were conducted for the 24-hour movement behaviors according to sociodemographic variables.@*Results@#The proportions of individuals meeting the MVPA, ST, and sleep guidelines were 32.2%, 78.5%, 30.1%, respectively. The proportion that meet 0, 1, 2 and 3 recommended items was 9.6%, 47.7%, 35.0% and 7.7%, respectively. Age, gender, parents’ education levels and family income showed associations with PA, ST and sleep. Compared with low parents’ education group, the risk for unhealthy behavioral patterns was lower in those with high parents’ education level(P<0.05).@*Conclusion@#The current status of 24-hour physical activity for children aged 6-13 in China is not ideal, and social demographics should be considered when designing targeted interventions to promote children’s health.

14.
Chinese Journal of School Health ; (12): 1775-1779, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-815581

RESUMO

Objective@#To investigate the associations of reallocating sedentary time to different activity behaviors with body composition, and to provide a reference for prevention and control of childhood obesity.@*Methods@#By using cluster random sampling, 1 621 students from 5 urban primary school in Guangzhou were selected in 2017. Vigorous intensity physical activity (VPA), moderate intensity physical activity (MPA), walking, sedentary behavior, and sleeping were measured by self-reported questionnaire. Inbody 230 was used to assess body composition. Multiple linear regression models were applied to examine isotemporal substitution effect of activity behaviors.@*Results@#In younger children group (aged 6-9 years), replacing 30 min/day sedentary with VPA was associated with a 0.9% lower fat-free mass index(FFMI)(β=0.11, P=0.00). In older children group (aged 10-12 years), replacing 30 min/day sedentary with VPA was associated with a 1.0% lower FFMI(β=0.13, P=0.04); replacing 30 min/day sedentary to walking was associated with both a 2.9% lower percentage of body fat(PBF)(β=-0.65, P<0.01) and a 4.0% lower fat mass index(FMI)(β=-0.18, P=0.00).@*Conclusion@#Replacing sedentary with other intensities of physical activity is crucial for improving fatness status among children aged 6 to 12 years, especially among children aged 10 to 12 years. This current study suggests that children should increase physical activity while reducing sedentary for reducing risk of childhood obesity.

15.
Chinese Journal of School Health ; (12): 1771-1774, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-815573

RESUMO

Objective@#To investigate the independent and joint associations of physical activity and sedentary behavior with 20 m shuttle run test (20 m SRT) performance among children.@*Methods@#Using cluster random sampling method, a total of 1 144 children aged 6-12 years from 1 urban primary school in Guangzhou were selected and completed the questionnaire survey, physical examination, and 20 m SRT. Physical activity and sedentary behavior were collected through questionnaire. Poor performance on 20 m SRT run test was defined as standard Z score ≤0, which was calculated according to gender, age-specific mean and standard deviation. Based on moderate-to-vigorous physical activity (MVPA) (≥60 min/d, 30-<60 min/d, or <30 min/d) and sedentary behavior levels (cut-off point: the gender, age-specific 50th percentile value), all participants were divided into six subgroups. Multiple linear regression and Logistic regression were used to analyze the independent and joint associations of physical activity and sedentary behavior with 20 m SRT performance, respectively.@*Results@#Low level of physical activity (β=-2.99, P<0.05) and high sedentary behavior (β=-1.75, P<0.05) were independently correlated with lower 20 m SRT performance. Compared with the reference group (MVPA≥60 min/d and low sedentary behavior), the risk for low performance on 20 m SRT was higher in those with MVPA<30 min/d, or those with high sedentary behavior. The risk for poor performance on 20 m SRT was gradually elevated with decreased physical activity levels in combination with higher level of sedentary behavior(P<0.05).@*Conclusion@#Physical activity and sedentary behavior were independently related to 20 m SRT performance among children. There is a clear does-response association, with elevated risks for poor performance on 20 m SRT with decreased physical activity levels in combination with higher level of sedentary behavior.

16.
Neurosci Lett ; 646: 43-48, 2017 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-28237799

RESUMO

In order to improve the poor water solubility of genistein (4',5,7-trihydroxyisoflavone), which is extracted from food sources such as tofu, soybeans, and kudzu, we sulfonated genistein to synthesize a relatively more water-soluble compound, namely genistein-3'-sodium sulfonate (GSS). Our previous studies demonstrate that GSS protects cortical neurons from injury induced by focal cerebral ischemia. However, the molecular mechanisms underlying this protective effect remain unclear. We aimed to investigate the protective effect and potential molecular mechanisms of action of GSS in rat glutamate-induced cortical neuron injury in vitro and middle cerebral artery occlusion (MCAO) in vivo models. Our results showed that GSS exhibited a protective effect against glutamate-induced cytotoxicity in rat cortical neurons by reducing lactate dehydrogenase (LDH) release, inhibiting cell apoptosis, increasing Bcl-2/Bax expression ratio, and reducing Caspase 3 activity. GSS also decreased the infarcted area and neurological deficits in the rat MCAO model, reduced LDH release from the brain tissue to the serum, increased the Bcl-2/Bax expression ratio, and reduced Caspase 3 activity. These findings suggest that GSS protects rat cortical neurons from injury induced by focal cerebral ischemia in both in vitro and in vivo models, through increased Bcl-2/Bax expression ratio and reduced Caspase 3 activity.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Genisteína/farmacologia , Infarto da Artéria Cerebral Média/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Isquemia Encefálica/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ratos Sprague-Dawley
17.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 28(3): 451-5, 2011 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-21774200

RESUMO

The occurrence of acute hypotensive episodes (AHE) in intensive care units (ICU) seriously endangers the lives of patients, and the treatment is mainly depended on the expert experience of doctors. In this paper, a model for predicting the occurrence of AHE in ICU has been developed using the theory of medical Informatics. We analyzed the trend and characteristics of the mean arterial blood pressure (MAP) between the patients who were suffering AHE and those who were not, and extracted the median, mean and other statistical parameters for learning and training based on support vector machine (SVM), then developed a predicting model. On this basis, we also compared different models consisted of different kernel functions. Experiments demonstrated that this approach performed well on classification and prediction, which would contribute to forecast the occurrence of AHE.


Assuntos
Diagnóstico por Computador/métodos , Hipotensão/diagnóstico , Modelos Cardiovasculares , Máquina de Vetores de Suporte , Doença Aguda , Previsões , Humanos , Unidades de Terapia Intensiva
18.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 27(3): 529-32, 543, 2010 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-20649012

RESUMO

Motion artifact is a significant source of noise in ambulatory physiologic signals and can affect the diagnoses seriously. To cope with this problem, we adopted certain methods for removing motion artifact from ECG signals via synchronous acquisition of the elector/skin impedance as the reference signal of adaptive filter. The results demonstrated that 3rd order RLS adaptive filter can remove the baseline shift effectively with an exciting current of 120 Hz and 50 microA. Such system was implemented to investigate the utility of ambulatory heart rate monitoring, which provides convenient and reliable monitoring services for patients.


Assuntos
Algoritmos , Artefatos , Eletrocardiografia/métodos , Processamento de Sinais Assistido por Computador , Impedância Elétrica , Humanos
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