AIM: To examine the expression of CD69 on NK cells at the fetomaternal interface in CBA/J?DBA/2 mice as a model of recurrent spontaneous abortion (RSA), and to evaluate the effects of lymphocyte immunotherapy (LIT) on the level of CD69 expression and the relationship with the outcomes of murine fetuses and pups. METHODS: The outcomes of murine fetuses and pups were evaluated in breeding pairs of CBA/J?DBA/2, C57BL/6?DBA/2 and BALB/c?DBA/2 mice. Both preweaning growth curves and Kaplan-Meier survival graphs of pups were constructed throughout postnatal days 1 to 21. In addition, the level of CD69 expression on NK cells at the fetomaternal interface with and without LIT were determined by two-color flow cytometric analysis, stained with PE-CD69 and FITC-DX5. The subpopulation of CD16/CD32 + NK cells was also evaluated. RESULTS: Statistically significant differences were observed between CBA/J?DBA/2 mice and normal fertile controls in the median increase of maternal weight during pregnancy, the number of pups born per litter, the median neonatal weight on postnatal day 1, and the resorption rate of fetuses. The proportion of CD69 +DX5 + cells which represents activated NK cells was significantly higher in CBA/J?DBA/2 mice compared with normal fertile controls, while efficient LIT was able to dramatically decrease the expression of CD69 on NK cells at the fetomaternal interface and this was associated with the decrease of resorption rate accordingly. CONCLUSION: The fraction of CD69 +DX5 + cells seems to be functionally important in the mechanisms by which the embryos were rejected, whereas efficient LIT is capable of reducing the abortion rate via decreasing the expression of CD69 molecules on NK cells at the fetomaternal interface.

Objective:To explore the teaching effect of individualized teaching based on problem-based learning (PBL) that applied in gynecology practice teaching under the background of conflicts between postgraduate examination preparation and clinical internship for medical undergraduates.Methods:A total of 157 medical students of the five-year program who started gynecology internship and meanwhile prepared for the postgraduate entrance examination in 2018 were enrolled in the study and divided into two groups randomly. One group received traditional teaching (control group), and the other group received individualized teaching mode based on PBL (observation group). After the internship, the two groups of students were assessed for their theoretical and clinical skills, and the students' evaluation of the teaching effect was acquired through a questionnaire survey. SPSS 22.0 was used to perform chi-square test.Results:The students in observation group had statistically significant higher scores in theory and skill tests than those in the control group ( P<0.001). The evaluation of boosting their enthusiasm for internship, advancing self-learning ability, conducing to improving learning methods in the future, and enhancing clinical skills and thinking ability in the observation group was significantly better than that in the control group ( P<0.05). Conclusion:The individualized teaching model based on PBL could efficiently alleviate the conflicts between internship and postgraduate entrance examination preparation and improve the effect of gynecology practice teaching.

COVID-19 ; Humans ; Kidney Transplantation ; Retrospective Studies ; SARS-CoV-2 ; Transplant Recipients