A longitudinal examination of the measurement properties and invariance of the Sleep Condition Indicator in Chinese healthcare students.

BACKGROUND: The Sleep Condition Indicator (SCI), an insomnia measurement tool based on the updated Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria with sound psychometric properties when applied in various populations, was evaluated here among healthcare students longitudinally, to demonstrate its measurement properties and invariance in this particularly high-risk population. METHODS: Healthcare students of a Chinese university were recruited into this two-wave longitudinal study, completing the simplified Chinese version of the SCI (SCI-SC), Chinese Regularity, Satisfaction, Alertness, Timing, Efficiency, Duration (RU_SATED-C) scale, Chinese Patient Health Questionnaire-4 (PHQ-4-C), and sociodemographic variables questionnaire (Q-SV) between September and November 2022. Structural validity, measurement invariance (MI), convergent and discriminant validity, internal consistency, and test-retest reliability of the SCI-SC were examined. Subgroups of gender, age, home location, part-time job, physical exercise, and stress-coping strategy were surveyed twice to test cross-sectional and longitudinal MI. RESULTS: We identified 343 valid responses (62.9% female, mean age = 19.650 ± 1.414 years) with a time interval of seven days. The two-factor structure was considered satisfactory (comparative fit index = 0.953-0.989, Tucker-Lewis index = 0.931-0.984, root means square error of approximation = 0.040-0.092, standardized root mean square residual = 0.039-0.054), which mostly endorsed strict invariance except for part-time job subgroups, hence establishing longitudinal invariance. The SCI-SC presented acceptable convergent validity with the RU_SATED-C scale (r ≥ 0.500), discriminant validity with the PHQ-4-C (0.300 ≤ r < 0.500), internal consistency (Cronbach's alpha = 0.811-0.835, McDonald's omega = 0.805-0.832), and test-retest reliability (intraclass correlation coefficient = 0.829). CONCLUSION: The SCI-SC is an appropriate screening instrument available for assessing insomnia symptoms among healthcare students, and the promising measurement properties provide additional evidence about validity and reliability for detecting insomnia in healthcare students.

[Intervention effects of Zuoguiwan containing serum on osteoblast through ERK1/2 and Wnt/ß-catenin signaling pathway in models with kidney-Yang-deficiency, kidney-Yin-deficiency osteoporosis syndromes].

To clarify the effects of Zuoguiwan containing serum on osteoblast proliferation and alkaline phosphatase(ALP) expression and its effects on the expression of ß-catenin, ERK1, ERK2 mRNA and protein of osteoblast through ERK1/2, Wnt/ß-catenin signaling pathway in models with osteoporosis(OP) kidney-Yang-deficiency, osteoporosis(OP) kidney-Yin-deficiency syndrome. Rat osteoporosis models were established by ovariectomy surgery, and 10 weeks after surgery, hydrocortisone was injected and thyroxine was administered by intragastric administration to establish OP kidney-Yang-deficiency rat model, and OP kidney-Yin-deficiency rat model. Osteoblasts were obtained from 24 h newborn rat skull and were identified by alkaline phosphatase and alizarin red staining. Zuoguiwan containing serum of OP, OP kidney-Yang-deficiency, and OP kidney-Yin-deficiency, as well as the blank serum were used to intervene the osteoblast, and the cells proliferation was detected by MTS. ELISA assay was used to detect ALP expression. RT-PCR assay was used to detect the mRNA expression of ERK1, ERK2, ß-catenin and protein expression levels were detected by Western blot. The results showed that Zuoguiwan containing serum in OP kidney-Yin-deficiency model had stronger effect than OP kidney-Yang-deficiency in promoting osteoblast proliferation, ALP expression, osteoblast ERK1/2, Wnt/ß-catenin signaling pathway related factors ß-catenin, ERK1, ERK2 mRNA and protein expression levels. This was consistent with the TCM theory of "Zuoguiwan nourishes kidney Yin", providing a scientific basis for the clinical and dialectical treatment of osteoporosis. Zuoguiwan could regulate the proliferation and differentiation of bone cells by ERK1/2 and Wnt/ß-catenin signaling pathway, which may be one of the mechanisms of Zuoguiwan for the prevention of osteoporosis.