BACKGROUND:Previous studies have shown that human dental pulp stem cells have good osteogenic differentiation potential and are potential seed cells in bone tissue engineering,and the effect of recombinant human growth hormone on the proliferative osteogenic differentiation of human dental pulp stem cells is still unclear. OBJECTIVE:To explore the effect of recombinant human growth hormone on the proliferation and osteogenic differentiation of human dental pulp stem cells. METHODS:Human dental pulp stem cells were isolated and cultured by tissue block culture method.After screening according to the drug concentration gradient,recombinant human growth hormone containing 10,100,250,500,1 000 μg/L was selected as the experimental group,and 0 μg/L without recombinant human growth hormone was selected as the control group.CCK-8 detection reagents were used on days 1,3,5,and 7 after the drug intervention to detect the proliferation of human dental pulp stem cells.Different concentrations(10,100,250,500,and 1 000 μg/L)of recombinant human growth hormone were added to the osteogenesis induction solution to intervene in human dental pulp stem cells.Alkaline phosphatase activity was detected by alkaline phosphatase staining and semi-quantitative analysis on day 7 of mineralization induction.The mRNA expression levels of osteogenic gene type I collagen,osteocalcin and Runt-related transcription factor 2 were detected by fluorescence quantitative RT-qPCR.Alizarin red staining was performed on day 14 of mineralization induction to detect osteogenic mineralized nodules. RESULTS AND CONCLUSION:(1)CCK-8 assay results showed that from the third day of intervention,the 100,250,500,1 000 μg/L recombinant human growth hormone group could promote the proliferation of human dental pulp stem cells compared with the control group(P<0.01).(2)The alkaline phosphatase activity of human dental pulp stem cells in the 100,250,and 500 μg/L recombinant human growth hormone group was significantly increased compared with the control group(P<0.01).The number of alizarin-stained mineralized nodules in human dental pulp stem cells in the 100,250 μg/L recombinant human growth hormone group was significantly increased compared with the control group(P<0.01).Compared with the control group,the mRNA expression of type I collagen and osteocalcin increased in the 250 μg/L recombinant human growth hormone group(P<0.05,P<0.01).mRNA expression of Runt-associated transcription factor 2 increased in the 100 and 250 μg/L recombinant human growth hormone groups(P<0.01).(3)According to the above results,recombinant human growth hormone at a concentration of 250 μg/L is a more suitable concentration to promote the proliferation and osteogenic differentiation of human dental pulp stem cells.

【Objective】 To investigate the current situation concerning volume control of red blood cells in additive solution produced by blood service in Chongqing, and to lay a foundation for promoting the homogenization of preparation process of red blood cells in additive solution. 【Methods】 A questionnaire was designed to investigate the factors related to the preparation of red blood cells in additive solution. The questionnaire was sent by Chongqing Association of Blood Transfusion via E-mail to 18 blood services in the city, and the collected data was sorted, revised and analyzed by research team. 【Results】 A total of 18 blood services(including 1 blood center + 1 sub-center, 6 central blood stations and 11 central blood banks) returned the questionnaires. The results showed that there were differences among blood services across Chongqing, regarding the centrifugal parameters during preparation, the operation mode and monitoring situation of the capacity control during preparation, and the formulation of the capacity standard of red blood cells in additive solution etc. 【Conclusion】 The preparation process of red blood cells in additive solution, produced by Chongqing blood services, should be further standardized, and the capacity control method of this product in Chongqing should be gradually unified to achieve regional homogeneity and to ensure blood safety.