Effects of high-pressure processing on the physicochemical and adsorption properties, structural characteristics, and dietary fiber content of kelp (Laminaria japonica).

To investigate the effects of high-pressure processing (HPP) on the physicochemical and adsorption properties and structural characteristics of kelp, kelp slice (KS) and kelp powder (KP) were treated under different pressures (300, 450, and 600 MPa) for 5 and 10 min. Compared to untreated KP, HPP-treated KP yielded a 1.31-fold increase in water holding capacity (600 MPa/5 min), a 0.12-fold increase in swelling capacity (450 MPa/10 min), a 1.33-fold increase in oil holding capacity (600 MPa/10 min), a 10-fold increase in glucose adsorption capacity (450 MPa/10 min), and a 0.22-fold increase in cholesterol adsorption capacity (163.1 mg/g DW at 450 MPa/10 min), and exhibited good Cd (Ⅱ) adsorption capacity when its concentration was 10 mmol/L in the small intestine. The physicochemical properties of HPP-treated KS were not improved due to its low specific surface area. In addition, HPP treatment efficiently reduced the particle size of KP and increased its total and soluble dietary fiber content by 17% and 63% at 600 MPa/10 min, respectively. Scanning electron microscope micrographs demonstrated that the surface of HPP-treated KP was rough and porous, and the specific surface area increased with increasing pressure and processing time. To conclude, the results obtained in the present study suggest that HPP is a promising processing method for improving the functionality and structural characteristics of KP and provide a theoretical basis for the utilization of HPP-treated KP as a fiber-rich ingredient in the functional food industry.

Risk factors of sitting-induced tachycardia syndrome in children and adolescents.

BACKGROUND: The study was designed to explore the risk factors for sitting-induced tachycardia syndrome (STS) in children and adolescents. METHODS AND RESULTS: In this case-control study, 46 children with STS and 184 healthy children and adolescents were recruited. Demographic characteristics, lifestyle habits, allergy history, and family history were investigated using a questionnaire. The changes in heart rate and blood pressure from supine to sitting were monitored using a sitting test. The possible differences between STS patients and healthy children were analyzed using univariate analysis. Logistic regression analysis was used to explore the independent risk factors for STS. Univariate analysis showed that the daily sleeping time of the STS children were significantly shorter than that of the control group [(8.8 ± 1.2) hours/day vs. (9.3 ± 1.0) hours/day, P = 0.009], and the proportion of positive family history of syncope in the STS patients was higher than the controls (4/42 vs. 3/181, P = 0.044). Multivariate logistic regression studies showed that reduced daily sleeping time was an independent risk factor of STS in children (P = 0.006). Furthermore, when daily sleeping time was prolonged by 1 h, the risk of STS was decreased by 37.3%. CONCLUSION: Reduced daily sleeping was an independent risk factor for STS in children and adolescents.

Sitting-induced hemodynamic changes and association with sitting intolerance in children and adolescents: a cross-sectional study.

Hemodynamic alteration with postural change from supine to sitting has been unclear in the young. In the cross-sectional study, 686 participants (371 boys and 315 girls, aged 6-18 years) were recruited from 4 schools in Kaifeng city, the central area of China. The active sitting test was performed to obtain heart rate (HR) and blood pressure (BP) changes from supine to sitting in children and adolescents. Hemodynamic change-associated sitting intolerance was analyzed. In the study participants, the 95th percentile (P95) values of changes in HR and BP within 3 min from supine to sitting were 25 beats/min and 18/19 mm Hg, respectively. Sixty-six participants had sitting intolerance symptoms. Compared with participants without sitting intolerance symptoms, those with symptoms more frequently had HR increase ≥ P95 or BP increase ≥ P95 within 3 min from supine to sitting (P < 0.001). Risk factors for sitting intolerance were age (odds ratio 1.218, 95% confidence interval 1.072-1.384, P = 0.002) and changes in HR or BP ≥ P95 within 3 min after sitting (odds ratio 2.902, 95% confidence interval 1.572-5.357, P = 0.001). We firstly showed hemodynamic changing profiles from supine to sitting and their association with sitting intolerance in children and adolescents. Sitting tachycardia is likely suggested with a change in HR ≥ 25 beats/min and sitting hypertension with a change in BP ≥ 20/20 mm Hg when changing from supine to sitting within 3 min. The age and changes in HR or BP were independent risk factors for sitting intolerance.