BACKGROUND:Culture condition,isolation method and efficiency are different in reported human umbilical cord-derived mesenchymal stem cells,which lack of unified identification standards.Therefore,it is necessary to establish a high-efficiency and economical culture system for human umbilical cord-derived mesenchymal stem calls(hUCMSCs).OBJECTIVE:To isolate hUCMSCs and induced differentiate into adipocytes and osteblasts.METHODS:The hUCMSCs were isolated form human umbilical cord by tissue adherence and digested with collagenase.The morphology,proliferation and immunophenotype of the 3rd passage cells were analyzed,and then cells were induced to osteogenic and adipogenic differentiation in vitro.RESULTS AND CONCLUSION:The hUCMSCs isolated from human umbilical cord by tissue adherence and digested with collagenase could be cultured and proliferated in vitro.Flow cytometry analysis revealed that the hUCMSCs were positive for CD29 CD44,CD59,CD105,but were negative for CD40,CD86 and HLA-DR.These calls could be induced to differentiate into adipocytes and osteblasts under proper inducing conditions.The hUCMSCs retained the appearance and phenotype even after being expanded more than 40 passages in vitro.This confirmed that the existence of MSCs in human umbilical cord and they had the capacity of differentiating into adipocytes and osteblasts.

Objective To investigate the relationship between vitamin A and vitamin E concentra-tions and preeclampsia. Methods A total of 160 pregnant women who were finished normal perinatal care and tested for serum vitamin A and vitamin E concentrations in the First Affiliated Hospital of Shenzhen Uni-versity (Shenzhen Second People's Hospital) from March 1, 2018 to February 28, 2019, including 80 pre-eclampsia cases and 80 healthy control cases were enrolled in the study. The concentrations of serum vita-mins A and E in early pregnancy ( <14 weeks) and late pregnancy (≥34 weeks) were determined by high performance liquid chromatography tandem mass spectrometry. The collected clinical and test data were sta-tistically analyzed. Results ⑴There was no significant difference in vitamin A concentration between pre-eclampsia group and control group during early pregnancy (P=0. 360) and there was no significant differ-ence in vitamin A concentration between preeclampsia group and control group during late pregnancy ( P=0. 450). ⑵ The concentration of vitamin E in early pregnant women in preeclampsia group was [(9. 51 ± 2. 82)mg/L], which was lower than that in healthy control group [(11. 19 ± 3. 04)mg/L], with significant statistically difference (t=8. 85, P=0. 01); the vitamin E concentration in late pregnant women in pre-eclampsia group was [(13. 52 ± 4. 40)mg/L], which was lower than that in healthy control group [(16. 20 ± 5. 00)mg/L], with significant statistically difference (t=10. 9, P=0. 01). ⑶Logistic regression anal-ysis showed that there was a correlation between vitamin E concentration in early pregnancy and late preg-nancy and preeclampsia. Conclusions There was no significant correlation between vitamin A concentra-tion and preeclampsia. Vitamin E may be involved in the pathogenesis of pre-eclampsia.