Objective To study the effects of short-term cryopreservation on the proliferation ,bio-characteristics and osteogenic capability of rabbit BMSCs and lay the foundation for the further study .Methods The 5th generation of rabbit BMSCs were cryo-preservated by liquid nitrogen for 30 days ,and then thawing the cells to culture it to the 10th generation in vitro ,put the non-cryo-preservated and the same generation BMSCs as the control group .The MTT ,cell cycle ,cell surface marker ,the content of ALP and the immunohistochemical staining for collagen typeⅠ and alizarin red staining for calcium after differentiation induced by osteogene-sis were used to evaluate the proliferation ,bio-characteristic and osteogenic differentiation capability of rabbit BMSCs .Results The growth incubation period of BMSCs after cryopreservated was extended ,but it gradually recover through serial passage .The prolif-eration index and the proportion of BMSCs in G1 phase were 42 .9% ± 3 .4% and 57 .0% ± 3 .4% respectively .The positive rate of cell surface marker of CD44 was 93 .62% ± 1 .05% without expression of CD45 .The contents of ALP(U/gprot) were 6 .73 ± 1 .92 and 15 .99 ± 4 .36 in BMSCs after 7th day and 14th day with osteogenic induction ,respectively .The collagen typeⅠ and alizarin red staining for calcium indicated positive at BMSCs after 14th day and 21th day with osteogenic induction ,respectively .These results showed no significant difference compared with the control group (P>0 .05) .Conclusion Short-term cryopreservation has no obvi-ous impacts on the proliferation ,bio-characteristic and osteogenic capability of BMSCs and it could be used for further study .

Objective To culture the rabbit bone marrow derived mesenchymal stem cells (BMSCs) ,and to observe their biologi-cal characteristics in vitro and the expression of BMP2 and EGFP after Ad-EGFP-BMP2 infected on them .Methods To isolate and cultivate BMSCs by density gradient centrifugation and adherent culture in vitro ;the cell cycle and the surface marks were detected by flow cytometer ;rabbit BMSCs were differentiated into the direction of osteogenetic cells by in vitro induction .After transfection , the expression of exogenous gene in the cells was detected by the immunocytochemical staining and Western blot .Results About 56 .84% of rabbit BMSCs cell cycle was in the G1 phase;the D44 expression was positive and the CD45 expression was negative ;af-ter induction by osteogenetic cells ,the Ⅰtype collagen immunohistochemical staining was positive and the alizarin red staining was positive .After transfection ,the strong expression of BMP2 and EGFP in cells was showed by Western blot and the immunocyto-chemical staining .Conclusion rabbit BMSCs are successfully isolated ,cultured and identified to have the ability of osteogenetic dif-ferentiation ;the structured Ad-BMP-2/EGFP can efficiently transfected rabit BMSCs and stably express the target gene of BMP 2 .

Objective To observe the biocompatibility of rabbit bone marrow mesenchymal stem cells (BMSCs)combined with allogeneic decalcified bone matrix(DBM)after transfecting adenoviral recombinant human bone morphogenetic protein-2(Ad-rhBMP-2).Methods The rabbit allogeneic DBM material was prepared according to the Ursit method.After transfecting Ad-BMP-2 on rabbit bone marrow mesenchymal stem cells,the immunohistochemical was used to detect the expression of BMP-2 in the transfected cells;after 48 h of transfection,the cells were planted on the allograft DBM,then the scanning electron microscopy was used to observe the cell growth and adhesion condition on material,and the proliferation condition of BMSCs was detected by MTT. Results After 48 h of adenoviral transfection,BMSCs could express BMP-2 successfully.The scanning electron microscopy showed that the cells after transfection adhered well and massively proliferated on DBM material.The MTT assay showed that the prolifer-ation condition of the cells after transfection planted on DBM was normal,which showed no statistically significant difference when compared with the control group (P >0.05).Conclusion The Ad-BMP-2 transfection on BMSCs is well biocompatible to allogene-ic DBM.

Objective: To explore the relationship of sleep quality and emotional regulation difficulties in middle school students, and to analyze its mediating role of daytime dysfunction, social rejection and selfcontrol ability, so as to provide a scientific reference for improving middle school students mental health. Methods: From October to November, 2023, the Pittsburgh Sleep Quality Index, Adolescent Social Rejection Questionnaire, Brief Selfcontrol Scale and Difficulties in Emotion Regulation Scaleshort Form (DERS-16) were used to assess 806 students recruited from four middle schools in Bengbu City by a convenient cluster random sampling method. And model-6 of PROCESS and 5 000 Bootstraps were used to make a chainmediating model analysis. Results: Daytime dysfunction was positively correlated with sleep quality(r=0.57), social rejection(r=0.19), selfcontrol(r=0.29, P＜0.01). Selfcontrol was positively correlated with emotional regulation difficulties(r=0.54, P<0.01).Poor sleep quality showed a significant positive association with on daytime dysfunction, and daytime dysfunction further affected social rejection, selfcontrol ability and emotional regulation difficulties (β=0.86, 0.60, 1.27, 1.56, P<0.05). Meanwhile, daytime dysfunction, social rejection and selfcontrol played a serial mediating role in the relationship between sleep quality and emotional regulation difficulties (Estimate=0.11,95%CI=0.04-0.20,P<0.05). Conclusion The study reveals the complex relationship between sleep quality and emotional regulation difficulties in middle school students and provides a new theoretical basis for adolescent sleep improvement and mental health interventions.

OBJECTIVE: To analyze the current status of core emergency response capability of nurses for systematically managing coronavirus disease(COVID-19) in intensive care units and to explore the related influencing factors. METHODS: A total of 100 nurses who systematically manage COVID-19 in the intensive care units from a class 3 grade A hospital in Wuhan City were selected as study subjects by convenience sampling method. The self-designed COVID-19 Core Emergency Response Capability Questionnaire for Nurses was used to investigate the status of COVID-19 core emergency response capability. RESULTS: The total score of the core emergency capability of the nurses averaged 133.1±18.1, and the scoring rate was 80.7%, which was at a high level. The scoring rates of each dimension from high to low were prevention ability, rescue ability and preparation ability, with the score rate of 85.2%, 81.7% and 71.0% respectively. The results of generalized linear regression analysis showed that the level of core emergency response capability of nurses was higher in high-risk departments such as respiratory department, infectious department, intensive care unit, outpatient department and emergency department than that of low-risk departments [partial regression coefficient(β) =11.18, P<0.01]. The levels of core emergency response capability of nurses who were married, once worked in the fever clinic, and were members of the National Health Emergency Rescue Team was higher(β were 8.28, 24.34 and 10.89, respectively, P<0.05). CONCLUSION: The core emergency response capability of nurses who systematically manage COVID-19 in the critical care units in Wuhan City is at a high level. Their core emergency response capability is affected by factors such as personal work experience, marital status, emergency work experience and trainings.

Objective To investigate the application value of the human B cell-confinement receptor P2RY8 in the diagnosis and prognosis of hepatocellular carcinoma (HCC) and its association with tumor immunity. Methods The Cancer Genome Atlas database was used to compare the expression of P2RY8. R software package was used to analyze the correlation between P2RY8 and tumor staging, and the receiver operating characteristic (ROC) curve and a nomogram model were established for diagnosis and survival. Tumor Immune Evaluation Resource was used to analyze immune cell infiltration, immune cell biomarkers, and immune checkpoints. STRING database was used to analyze protein-protein interaction network information. Gene ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were used to analyze the function of P2RY8 and its interacting genes. For the purpose of validation, HCC tissue samples were collected from 64 patients who underwent radical surgery for HCC from June 2007 to November 2008, and the corresponding adjacent tissue samples were collected from 35 patients out of these patients (tissue chips were purchased from Shanghai Outdo Biotech Co., Ltd.); related clinical data and follow-up data were analyzed, and immunohistochemistry was used to measure the expression of P2RY8 in HCC and adjacent tissue samples. The t -test was used for comparison of normally distributed continuous data between two groups; the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between two groups, and the Kruskal-Wallis H test was used for comparison between multiple groups. The chi-square test was used for comparison of categorical data between two groups. A Spearman correlation analysis was used to investigate the correlation between two variables. The Kaplan-Meier method was used to plot survival curves, and the log-rank test was used to calculate survival rates. Results P2RY8 was overexpressed in HCC, and the expression level of P2RY8 could accurately differentiate tumor from normal tissue, with an area under the ROC curve of 0.794. The patients with a higher expression level of P2RY8 tended to have a better prognosis ( P =0.005). The data from 64 clinical samples also confirmed that compared with the patients with a low expression level of P2RY8, the patients with a high expression level of P2RY8 had significantly higher 3-year survival rate (78.9% vs 46.2%, P =0.007), 5-year survival rate (76.3% vs 38.5%, P =0.002), and overall survival time [92.5 (48.8-102.0) months vs 33.0 (25.0-95.5) months, P =0.022], and the Kaplan-Meier survival curve further indicated that the expression level of P2RY8 was associated with the prognosis of HCC patients. In addition, P2RY8 was positively correlated with immune cell infiltration and immune checkpoint in HCC. The GO/KEGG pathway enrichment analyses showed that P2RY8 was enriched in the signal transduction pathways such as humoral immunity and cellular immunity. Conclusion P2RY8 participates in the development, progression, and immune regulation of HCC, and therefore, P2RY8 can serves as a potential biomarker and a therapeutic target for the diagnosis and prognosis of HCC.