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Fulltext The Chinese version of the physical activity questionnaire for adolescents: a psychometric validity, reliability, and invariance study

Qin L, Ho WKY, Khoo S

BMC Public Health, 2024 Nov 11;24(1):3117.
PMID: 39529046 DOI: 10.1186/s12889-024-20563-0

BACKGROUND: The Physical Activity Questionnaire for Adolescents (PAQ-A) is one of the most commonly used questionnaires for assessing adolescents' levels of moderate to vigorous physical activity (PA). Although a Chinese version of the PAQ-A (comprising nine items) exists, it has been assessed for only internal consistency coefficients, test-retest reliability, and correlations with the GT3X + accelerometer. Therefore, this study aimed to evaluate the psychometric properties of the Chinese version of the PAQ-A among Chinese adolescents.
METHODS: This study included three samples of 1,101 secondary school students (12-19 years old). The first sample consisted of 518 participants (50.4% males, 49.6% females) for correlation tests and exploratory factor analysis (EFA). The second sample consisted of 227 participants (55.75% males, 44.24% females) for confirmatory factor analysis (CFA), convergent validity, and sample size invariance tests. The third sample consisted of 356 participants (54.50% male, 45.50% female) for the internal consistency reliability test, invariance test (cross sample size, education level and gender), and t-test.
RESULTS: Pearson correlation analysis of the PAQ-A indicated that all the total-item correlations exceeded 0.2, indicating good consistency across the items. Subsequent EFA of the Chinese version of the PAQ-A revealed a two-factor structure. CFA subsequently validated this structure. One of the items exhibited a standardized loading below 0.4 and was excluded. The exclusion of this item resulted in increased standardized loadings for the remaining items, ranging from 0.40 to 0.82, which indicates improved fit indices. This adjustment underscores the questionnaire's satisfactory convergent validity and robust discriminant validity. The overall Cronbach's alpha was 0.821, with the values for the first and second factors being 0.757 and 0.716, respectively. The questionnaire demonstrated stable invariance across sample sizes and education levels and additionally showed partial scalar invariance across genders. A t-test revealed a significant difference between males and females, which aligns with previous findings. These findings supported the construct validity of the questionnaire.
CONCLUSION: This study validated the Chinese version of the PAQ-A for assessing adolescent PA in China, with a two-factor structure improved by removing one item.
Crystal structures of Nipah and Hendra virus fusion core proteins

Lou Z, Xu Y, Xiang K, Su N, Qin L, Li X, et al.

FEBS J, 2006 Oct;273(19):4538-47.
PMID: 16972940

The Nipah and Hendra viruses are highly pathogenic paramyxoviruses that recently emerged from flying foxes to cause serious disease outbreaks in humans and livestock in Australia, Malaysia, Singapore and Bangladesh. Their unique genetic constitution, high virulence and wide host range set them apart from other paramyxoviruses. These characteristics have led to their classification into the new genus Henpavirus within the family Paramyxoviridae and to their designation as Biosafety Level 4 pathogens. The fusion protein, an enveloped glycoprotein essential for viral entry, belongs to the family of class I fusion proteins and is characterized by the presence of two heptad repeat (HR) regions, HR1 and HR2. These two regions associate to form a fusion-active hairpin conformation that juxtaposes the viral and cellular membranes to facilitate membrane fusion and enable subsequent viral entry. The Hendra and Nipah virus fusion core proteins were crystallized and their structures determined to 2.2 A resolution. The Nipah and Hendra fusion core structures are six-helix bundles with three HR2 helices packed against the hydrophobic grooves on the surface of a central coiled coil formed by three parallel HR1 helices in an oblique antiparallel manner. Because of the high level of conservation in core regions, it is proposed that the Nipah and Hendra virus fusion cores can provide a model for membrane fusion in all paramyxoviruses. The relatively deep grooves on the surface of the central coiled coil represent a good target site for drug discovery strategies aimed at inhibiting viral entry by blocking hairpin formation.
Comparison of virus-capsid mimicking biologic-shell based versus polymeric-shell nanoparticles for enhanced oral insulin delivery

Cui Z, Cui S, Qin L, An Y, Zhang X, Guan J, et al.

Asian J Pharm Sci, 2023 Sep;18(5):100848.
PMID: 37881796 DOI: 10.1016/j.ajps.2023.100848

Virus-capsid mimicking mucus-permeable nanoparticles are promising oral insulin carriers which surmount intestinal mucus barrier. However, the impact of different virus-capsid mimicking structure remains unexplored. In this study, utilizing biotin grafted chitosan as the main skeleton, virus-mimicking nanoparticles endowed with biologic-shell (streptavidin coverage) and polymeric-shell (hyaluronic acid/alginate coating) were designed with insulin as a model drug by self-assembly processes. It was demonstrated that biologic-shell mimicking nanoparticles exhibited a higher intestinal trans-mucus (>80%, 10 min) and transmucosal penetration efficiency (1.6-2.2-fold improvement) than polymeric-shell counterparts. Uptake mechanism studies revealed caveolae-mediated endocytosis was responsible for the absorption of biologic-shell mimicking nanoparticles whereas polymeric-shell mimicking nanoparticles were characterized by clathrin-mediated pathway with anticipated lysosomal insulin digestion. Further, in vivo hypoglycemic study indicated that the improved effect of regulating blood sugar levels was virus-capsid structure dependent out of which biologic-shell mimicking nanoparticles presented the best performance (5.1%). Although the findings of this study are encouraging, much more work is required to meet the standards of clinical translation. Taken together, we highlight the external structural dependence of virus-capsid mimicking nanoparticles on the muco-penetrating and uptake mechanism of enterocytes that in turn affecting their in vivo absorption, which should be pondered when engineering virus-mimicking nanoparticles for oral insulin delivery.
Mental Health, Loneliness, and Social Support Among Undergraduate Students: A Multinational Study in Asia

Backhaus I, Fitri M, Esfahani M, Ngo HT, Lin LJ, Yamanaka A, et al.

Asia Pac J Public Health, 2023 May;35(4):244-250.
PMID: 37226778 DOI: 10.1177/10105395231172311

In this study, we aimed to investigate the prevalence of poor mental health and its association with loneliness and social support among 3531 undergraduate students in nine Asian countries. Mental health was assessed using the Self-Reporting Questionnaire, which was developed by the World Health Organization. Across the entire sample, we detected that nearly half of the students reported poor mental health according to the Self-Reporting Questionnaire and nearly one out of seven students felt lonely. While feeling lonely increased the odds of experiencing poor mental health (odds ratio [OR]), moderate (OR: 0.35) and strong social support (OR: 0.18) decreases the odds of experiencing poor mental health. The high prevalence of poor mental health calls for further in-depth investigations and implementation of mental health support interventions.
Fulltext PDLLA-Zn-nitrided Fe bioresorbable scaffold with 53-μm-thick metallic struts and tunable multistage biodegradation function

Shen D, Qi H, Lin W, Zhang W, Bian D, Shi X, et al.

Sci Adv, 2021 Jun;7(23).
PMID: 34088662 DOI: 10.1126/sciadv.abf0614

Balancing the biodegradability and mechanical integrity of a bioresorbable scaffold (BRS) with time after implantation to match the remodeling of the scaffolded blood vessel is important, but a key challenge in doing so remains. This study presents a novel intercalated structure of a metallic BRS by introducing a nanoscale Zn sacrificial layer between the nitrided Fe platform and the sirolimus-carrying poly(d,l-lactide) drug coating. The PDLLA-Zn-FeN BRS shows a multistage biodegradation behavior, maintaining mechanical integrity at the initial stage and exhibiting accelerated biodegradation at the subsequent stage in both rabbit abdominal aortas and human coronary arteries, where complete biodegradation was observed about 2 years after implantation. The presence of the nanoscale Zn sacrificial layer with an adjustable thickness also contributes to the tunable biodegradation of BRS and allows the reduction of the metallic strut thickness to 53 μm, with radial strength as strong as that of the current permanent drug-eluting stents.