Objective To study the effect of cryopreservation on some biological properties of rabbit adipose -de-rived mesenchymal stem cells (rADMSCs).Methods rADMSCs culture was isolated by tissue explants adherent meth-od.Morphology of the primary cells was observed by inverted microscopy .Immunophenotypes of the rADMSCs were deter-mined using flow cytometry .The third passage cells were preserved in liquid nitrogen for 6 months, and then were thawed , and subcultured to passage 7.The growth curves of the cryopreserved cells were analyzed by MTT assay , and the cryopre-served cells were cultured in adipogenic and osteogenic medium , with non-cryopreserved rADMSCs as a control group .The adipogenic and osteogenic abilities of the rADMSCs were evaluated by oil red O staining , alizarin red staining and alkaline phosphatase activity assay , respectively.Results The rADMSCs cultured in vitro exhibited a spindle-shaped appearance and rapid growth expansion .Flow cytometry analysis revealed that the third passage rADMSCs were CD 44-and CD90-posi-tive, but negative for hematopoietic cells surface marker CD 45.The growth curves of cells in the experimental and control groups were “S” shaped, showing a non-significant difference between the two groups (P>0.05).The oil red O staining and alizarin red staining results were positive at 2 weeks after adipogenic and osteogenic induction .The ALP activities of the two groups were increased with osteogenic induction time , with a non-significant difference (P>0.05).Conclusions Cryopreservation does not affect the growth and differentiation pluripotency of rADMSCs significantly .

Objective:To isolate SD rat adipose-derived stem cells(ASCs)by suspended explant culture method.Methods: The healthy rat inguinal fat pads were obtained.The SD rat ASCs were isolated by suspended explant culture method and explant adherent culture method.The growth status and morphology were observed.The growth curve and cell surface markers CD29,CD44,CD45 of the 3rd passage cells were analyzed respectively by CCK-8,immunocytochemistry;the 3rd passage cells were induced individually by adipogenic differentiation medium and osteogenic differentiation medium,and cells were examined by oil red O staining and alizarin red staining.Results: The SD rat ASCs obtained by the two methods exhibited a spindle-shaped appearance and could rapidly expand.The cell growth curves were typical of S type.Immunocytochemistry analysis revealed that the third passage of SD rat ASCs were positive for CD29,CD44,but were negative for CD45.SD rat ASCs were positive for oil red O staining at 14 days after adipogenic induction,and positive for alizarin red staining at 14 days after osteogenic induction.Conclusion: Isolation of SD rat ASCs by suspended explant culture method is successfully established.The method is simple.It provides a new method for the isolation of SD rat ASCs in vitro.

Objective To explore the value of combined detection of lipoprotein-associated phospholipase A2(Lp-PLA2),neuron specific enolase(NSE)and S-100 calcium binding protein β(S-100β)in the diagnosis and prognosis evaluation of acute cerebral infarction(ACI)in patients with carbon monoxide poisoning(CMP).Methods A total of 102 patients with CMP complicated with ACI admitted to the hospital from Jan-uary 2020 to November 2021 were selected as the study group,meanwhile,102 patients with simple CMP were enrolled as the control group.Patients in the study group were followed up for 6 months after discharge,ac-cording to the follow-up results,they were grouped into good prognosis group(60 cases)and poor prognosis group(42 cases).The serum levels of Lp-PLA2,NSE and S-100β were detected by enzyme-linked immunosor-bent assay(ELISA).The receiver operating characteristic(ROC)curve was applied to analyze the value of the combination of serum Lp-PLA2,NSE and S-100β in the early diagnosis and prognosis evaluation of patients with CMP and ACI.Results Compared with the control group,the levels of Lp-PLA2,NSE and S-100β in the study group were obviously higher(P<0.05).The ROC curve analysis results showed that the area under the curve(AUC)of the combined detection of serum Lp-PLA2、NSE、S-100β for the diagnosis of CMP complicat-ed with ACI was greater than the AUC of single detection of each indicator(P<0.001).Compared with the good prognosis group,the levels of Lp-PLA2,NSE and S-100β in the poor prognosis group were obviously higher(P<0.05).The results of ROC curve analysis showed that the AUC of the combined detection of ser-um Lp-PLA2、NSE、S-100β for the prognosis of patients with CMP complicated with ACI was greater than the AUC of single detection of each indicator(P<0.05).Conclusion The expression of Lp-PLA2,NSE and S-100β in serum of patients with CMP complicated with ACI is high,and the combined detection of the three has certain value in the diagnosis and prognosis evaluation for patients with CMP complicated with ACI.

Objective To analyze the timeliness of the start time of the first elective operation in a hospital and observe its impact on the operating room cost.Methods Make statistics and analysis on the opening of the first operation in a hospital,record the on-time opening rate of the first operation,analyze the reasons for the delay in the opening time of the first operation,formulate corresponding intervention measures and set up a"management team to improve the efficiency of operating room use".The on-time rate of the first operation,operation,cost control and the satisfaction of surgeons and patients were compared before and after the operation.Results The overall punctuality rate of the first operation was 53.74％,among which the colorectal sur-gery department had the highest punctuality rate of 63.16％,while the minimally invasive surgery department had the lowest punctuality rate of 45.45％.The main reasons for the delay of first operation(35.29％),failed anesthesia(30.88％),and the termination of the operation(17.65％);compared with before implementation,higher overtime time of nurses,shorter opening time and expected time,decreased interval between operation(P＜0.05),lower frequency of centralized delivery and unnecessa-ry consumables cost within 1 month after implementation(P＜0.05),and higher satisfaction of patients and physicians after im-plementation(P＜0.05).Conclusion By improving the first elective operation on time,can effectively reduce the cost of the operating room,shorten the nurse overtime time,at the same time improve the satisfaction of doctors and patients,and improve the management efficiency of the operating room,the first operation on time improved,interval time and unnecessary consumables costs are significantly reduced,optimize the use efficiency of the operating room resources.