has been recognized as a new human disease [1]. The causative agent was identified as a novel coronavirus strain, named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by the Coronavirus Study Group (CSG) [2]. The mortality rate of SARS-CoV-2 is lower than those of Middle East respiratory syndrome coronavirus (MERS-CoV) and severe acute respiratory syndrome coronavirus (SARS-CoV) [3]. However, SARS-CoV-2 spreads more rapidly than MERS-CoV and SARS-CoV because viral load and infectiousness peak before or around the time of symptom onset, i.e. much earlier than for both MERS-CoV and SARS-CoV [3]. The high transmissibility of SARS-CoV-2 is denoted by a basic reproduction number (R0) of 3.39 over the whole epidemic period [4]. Moreover, COVID-19 can be transmitted by asymptomatic carriers during the incubation period [4-7], probably because they carry viral loads similar to those of symptomatic patients [8]. Although further studies are warranted to ascertain the epidemiological significance of www.aging-us.com

The present study was designed to evaluate the effects of selenium-containing tea polysaccharides (Se-GTP) from a new variety of selenium-enriched Ziyang green tea against high fructose (HF)-induced insulin resistance and hepatic oxidative stress in mice. Healthy male Kunming mice were fed 20% high fructose water and administered 200, 400 and 800 mg per kg bw Se-GTP for 8 weeks. Mice fed HF in drinking water displayed significant insulin resistance, hepatic steatosis and oxidative stress observed by hyperglycemia and hyperinsulinemia, as well as increases in hepatic non-esterified fatty acid (NEFA) and malonaldehyde (MDA). The administration of Se-GTP at 400 and 800 mg per kg bw significantly improved insulin sensitivity, and reduced liver steatosis and oxidative stress damage, and brought back the antioxidants and hepatic lipids towards near-normal values. In the oral glucose tolerance test, the administration of Se-GTP at 400 and 800 mg per kg bw had reduced plasma glucose concentrations after 30 min of glucose loading in HF-fed mice, suggesting that Se-GTP improved glucose intolerance. Histopathological examination indicated that the impaired pancreatic/hepatic tissues were effectively restored in HF-fed mice following the Se-GTP treatment. This is the first report showing that Se-GTP can ameliorate the high fructose-induced insulin resistance and hepatic oxidative injury.

School socioeconomic status (SES) is studied primarily as a variable to explain academic achievement; however, few previous studies have investigated how SES can influence individual student’s academic achievement. The present study used a national representative sample of 10,784 grade 7 to 9 students (53.2% boys and 46.8% girls) in mainland China to examine the links between school SES and students’ math and Chinese achievements, including the math and Chinese teacher-student relationships as mediating factors. The parents provided family socioeconomic information and the students reported on their teacher-student relationships. Achievements in math and Chinese were assessed using standardized tests. Multilevel mediation analyses revealed that school SES was positively related to students’ math and Chinese achievements. Moreover, the link between school SES and students’ math achievement was partially mediated by students’ perception of the math teacher-student relationship. The Chinese teacher-student relationship had no mediating effect. This study indicated that school SES can influence individual student’s academic achievement via their perception of teacher-student relationship. The poverty and lack of resources is obvious, yet low SES schools could make efforts in improving teacher-student relationship’s quality to promote students’ academic performance. Meanwhile, low SES schools should receive more attention from policymakers to improve teaching quality and school climate. Furthermore, the study findings could be used for future research on the gap between low and high SES schools.

BackgroundIn Western countries, a history of major depression (MD) is associated with reports of received parenting that is low in warmth and caring and high in control and authoritarianism. Does a similar pattern exist in women in China?MethodReceived parenting was assessed by a shortened version of the Parental Bonding Instrument (PBI) in two groups of Han Chinese women: 1970 clinically ascertained cases with recurrent MD and 2597 matched controls. MD was assessed at personal interview.ResultsFactor analysis of the PBI revealed three factors for both mothers and fathers: warmth, protectiveness, and authoritarianism. Lower warmth and protectiveness and higher authoritarianism from both mother and father were significantly associated with risk for recurrent MD. Parental warmth was positively correlated with parental protectiveness and negatively correlated with parental authoritarianism. When examined together, paternal warmth was more strongly associated with lowered risk for MD than maternal warmth. Furthermore, paternal protectiveness was negatively and maternal protectiveness positively associated with risk for MD.ConclusionsAlthough the structure of received parenting is very similar in China and Western countries, the association with MD is not. High parental protectiveness is generally pathogenic in Western countries but protective in China, especially when received from the father. Our results suggest that cultural factors impact on patterns of parenting and their association with MD.

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Background and aimsTo understand the interaction between problematic smartphone use (PSU) and related influencing factors (individual variables, family environment, and school environment) and to determine the most influential factors affecting the use of smartphones by juveniles to implement effective interventions in the future.MethodsA total of 3,442 children and adolescents (3,248 actual participants (males = 1,638, average age = 12.27 ± 2.36)) were included in the study. This study measured juveniles’ PSU and its influencing factors: individual variables (4 factors), family environments (13 factors), and school environments (5 factors). This study employed a network analysis approach for data assessment.ResultsThis study found that there were several central influencing factors (such as self-control ability, loss of control, parent-child relationship, and peer attitudes towards smartphone use) and bridge factors (such as peer attitudes towards smartphone use, peer pressure for smartphone use, and fear of missing out).Discussion and conclusionsJuveniles’ PSU included several core symptoms and critical influencing factors. Intervention based on these factors may be effective, timely, and inexpensive.

The present study was designed to investigate the protective effects of Ilex Kuding tea polysaccharides (IKTP) on high fructose (HF)-induced liver injury and vascular endothelial dysfunction in mice. IKTP were identified as acidic heteropolysaccharides by FT-IR and HPLC. Healthy male Kunming mice fed 20% fructose in drinking water for 8 consecutive weeks significantly displayed dyslipidemia, hepatic steatosis, oxidative stress and vascular endothelial dysfunction. However, continuous administration of IKTP at 200, 400 and 800 mg per kg bw in HF-fed mice could prevent the damage caused by HF-diets, especially at dosages of 400 and 800 mg per kg bw (p < 0.01). IKTP significantly reduced the HF-induced elevation of the serum TC, TG, LDL-C, TXA and ET-1 levels, as well as AST and ALT activities, while markedly increased the HF-induced decline of HDL-C, PGI and eNOS levels in the serum compared to HF-fed mice. Meanwhile, the hepatic MDA level was lowered while SOD and GSH-Px activities were increased in IKTP-treated mice, compared to HF-fed mice. Histopathology of the liver and cardiovascular aortic by H&E or oil red O staining confirmed the liver steatosis and the vascular injury induced by HF-diets and the protective effects of IKTP. These findings suggest that HF causes oxidative damage, and IKTP alleviates liver injury and vascular endothelial dysfunction.

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