Objective To investigate and observe the morphology of subcutaneous induced membrane and osteogenic factor expres-sion of the novel material calcium hydroxide-bone cement.Methods 15 4-week-old Specific Pathogen Free(SPF)female Kunming mice were randomly divided into three groups(n=5):experimental group,control group and blank group.A cut running deep under the skin was made on the back side,calcium hydroxide-bone cement was placed subcutaneously in the experimental group,the Polymethyl Methacrylate(PMMA)was placed subcutaneously in the control group,the blank group only with operation.After 6 weeks,the subcuta-neous tissue surrounded the material was taken from each group to be observed the pathological structure,calculated the collagen volume fraction(CVF)and detected the positive expression and relative expression of osteogenic factors such as bone morphogenetic protein-2(BMP-2),transforming growth factor-β1(TGF-β1)and vascular endothelial growth factor(VEGF)in the subcutaneous tissues.Results Comparing with the pathological sections of the blank group,there were induced membrane structure rich in collagenous fiber,microvessel and cell in subcutaneous tissue of the control and experimental groups.Comparing with control group,there were decrease of inflammatory cells,collagen content,microvessels,and disorder of collagenous fiber in experimental group.Comparing the CVF,average optical density(AOD)of osteogenic factors and grey scale value of protein bands in each group,the blank group,experimental group and control group increased sequentially,and there was a significant difference between each group(P＜0.05).Conclusion The new mate-rial,calcium hydroxide-bone cement,can form an induced membrane structure subcutaneously,but the 6-week induced membrane was not as good as the PMMA induced membrane during the same period in terms of morphology and osteogenic factor levels.

Objective To investigate and observe the morphology of subcutaneous induced membrane and osteogenic factor expres-sion of the novel material calcium hydroxide-bone cement.Methods 15 4-week-old Specific Pathogen Free(SPF)female Kunming mice were randomly divided into three groups(n=5):experimental group,control group and blank group.A cut running deep under the skin was made on the back side,calcium hydroxide-bone cement was placed subcutaneously in the experimental group,the Polymethyl Methacrylate(PMMA)was placed subcutaneously in the control group,the blank group only with operation.After 6 weeks,the subcuta-neous tissue surrounded the material was taken from each group to be observed the pathological structure,calculated the collagen volume fraction(CVF)and detected the positive expression and relative expression of osteogenic factors such as bone morphogenetic protein-2(BMP-2),transforming growth factor-β1(TGF-β1)and vascular endothelial growth factor(VEGF)in the subcutaneous tissues.Results Comparing with the pathological sections of the blank group,there were induced membrane structure rich in collagenous fiber,microvessel and cell in subcutaneous tissue of the control and experimental groups.Comparing with control group,there were decrease of inflammatory cells,collagen content,microvessels,and disorder of collagenous fiber in experimental group.Comparing the CVF,average optical density(AOD)of osteogenic factors and grey scale value of protein bands in each group,the blank group,experimental group and control group increased sequentially,and there was a significant difference between each group(P＜0.05).Conclusion The new mate-rial,calcium hydroxide-bone cement,can form an induced membrane structure subcutaneously,but the 6-week induced membrane was not as good as the PMMA induced membrane during the same period in terms of morphology and osteogenic factor levels.

Objective:To compare the efficacy between laparoscopy and open surgery for gastric gastrointestinal stromal tumor (GIST) larger than 2 cm.Methods:A multicenter retrospective cohort study was performed. Inclusion criteria: long diameter of primary gastric GIST > 2 cm; undergoing laparoscopy or open surgery; diagnosis confirmed by postoperative pathology without distant metastasis; without preoperative targeted therapy. Clinicopathological data of 857 gastric GIST patients, including 320 in PLA General Hospital, 284 in Shanghai Renji Hospital, 175 in Wuhan Union Hospital and 78 in Tianjin Cancer Hospital, from January 2010 to May 2017 were retrospectively collected. There were 418 males and 439 females, mainly aged between 50 and 70 years old. Among 857 patients, 413 were in the laparoscopy group and 444 in the open group. The nearest neighbor matching of propensity score matching method was conducted with 1:1 matching based on tumor location and size between laparoscopy and open group to obtain samples of covariate equilibrium, and the caliper value was 0.04. The t test, χ 2 test and Wilcoxon rank test were used to compare short-term efficacy, and the Kaplan-Meier curve and log rank test were applied to compare long-term outcomes between the two groups. Results:After propensity score matching, laparoscopy group and open group both enrolled 293 cases. The baseline data, including age, gender, tumor location, tumor long diameter, NIH classification, etc. were not significantly different between the two groups (all P>0.05). Compared with the open group, the laparoscopy group had less intraoperative blood loss [<100 ml: 2.9% (155/293) vs. 36.2% (106/293), Z=-12.857, P<0.001], shorter time to postoperative feeding [(4.0±0.2) days vs. (5.3±0.9) days, t=1.505, P=0.003] and to the removal of drainage tube [(4.8±1.0) days vs. (6.5±1.0) days, t=1.847, P=0.008], and shorter postoperative hospital stay [(8.6±0.3) days vs. (10.5±0.3) days, t=4.235, P<0.001]. Subgroups analysis according to anatomical location: (1) Gastric cardia and pylorus: there were no statistically significant differences in perioperative parameters between the two groups (all P>0.05). (2) Stomach base: feeding time after surgery [(4.0±0.2) days vs. (4.5±0.2) days, t=0.512, P=0.038], drainage tube removal time [(5.1±0.4) days vs. (6.4±0.6) days, t=0.517, P=0.044], postoperative hospital stay [(8.0±0.5) days vs. (11.1±0.9) days, t=0.500, P=0.002] were all significantly shorter in the laparoscopy group as compared to the open group, while the differences in other perioperative parameters were not statistically significant (all P>0.05). (3) Lesser curvature of the stomach: the laparoscopy group had less intraoperative blood loss [<100 ml ratio: 58.1% (43/74) vs. 33.7% (25/74), Z=7.632, P=0.034], shorter gastric tube removal time [(2.7±0.2) days vs. (3.2±0.3) days, t=0.503, P=0.007], earlier postoperative passage of gas [(2.8±0.1) days vs. (3.4±0.2) days, t=0.532, P=0.030], earlier postoperative feeding [(3.6±0.2) days vs. (4.3±0.2) days, t=0.508, P=0.020], shorter drainage tube removal time [(4.2±0.4) days vs. (5.7±0.5) days, t=0.508, P=0.020] and postoperative hospital stay [(8.3±0.6) days vs. (10.7±0.3) days, t=0.502, P=0.006] as compared to the open group. (4) Great curvature of the stomach: the laparoscopy group presented less intraoperative blood loss [<100 ml ratio: 52.7% (39/74) vs. 36.5% (27/74), Z=7.681, P=0.032], earlier gastric tube removal [(2.6±0.2) days vs. (3.6±0.2) days, t=0.501, P=0.001], earlier postoperative passage of gas [(2.7±0.2) days vs. (3.4±0.2) days, t=0.501, P=0.016], earlier postoperative feeding [(3.6±0.2) days vs. (4.7±0.2) days, t=0.500, P=0.001], shorter drainage tube removal time [(4.0±0.5) days to (5.9±0.4) days, t=0.508, P=0.002] and postoperative hospital stay [(7.5±0.3) days to (9.5±0.1) days, t=0.500, P=0.001] than the open group. Subgroup analysis according to tumor size: (1) Tumor long diameter 2.0-5.0 cm: the laparoscopy group had earlier passage of gas [(2.9±0.1) days vs. (3.5±0.1) days, t=0.500, P=0.001], earlier postoperative feeding [(4.5±0.1) days vs. (5.0±0.2) days, t=0.501, P=0.013], shorter drainage tube removal time [(4.8±0.3) days vs. (6.0±0.3) days, t=0.511, P=0.008] and postoperative hospital stay [(8.1±0.4) days to (10.1±0.3) days, t=0.513, P=0.001] than the open group. (2) Tumor long diameter 5.1-10.0 cm: in the laparoscopic group, postoperative feeding time [(4.0±0.2) days vs. (4.7±0.2) days, t=0.506, P=0.015], drainage tube removal time [(4.6±0.4) days vs. (6.4±0.5)) days, t=0.501, P=0.004], postoperative hospital stay [(8.2±0.3) days vs. (10.9±0.6) days, t=0.500, P=0.001] were all shorter than those in the open group. No intraoperative and postoperative complications were observed in each group. The 5-year recurrence-free survival rates of the laparoscopy group and the open group were 95.4% and 91.6%, respectively ( P=0.734), and the 5-year overall survival rates were 93.8% and 90.8% ( P=0.691), respectively, and the differences were not statistically significant. Conclusions:In experienced medical centers, laparoscopic surgery for gastric GIST larger than 2 cm is safe and feasible, and can achieve comparable efficacy with open surgery. For gastric GISTs which do not locate in the greater curvature and the anterior wall of the stomach, and whose long diameter is ≤5 cm, laparoscopic surgery does not increase the risk of recurrence and metastasis, and can accelerate postoperative recovery.

Objective:To compare the efficacy between laparoscopy and open surgery for gastric gastrointestinal stromal tumor (GIST) larger than 2 cm.Methods:A multicenter retrospective cohort study was performed. Inclusion criteria: long diameter of primary gastric GIST > 2 cm; undergoing laparoscopy or open surgery; diagnosis confirmed by postoperative pathology without distant metastasis; without preoperative targeted therapy. Clinicopathological data of 857 gastric GIST patients, including 320 in PLA General Hospital, 284 in Shanghai Renji Hospital, 175 in Wuhan Union Hospital and 78 in Tianjin Cancer Hospital, from January 2010 to May 2017 were retrospectively collected. There were 418 males and 439 females, mainly aged between 50 and 70 years old. Among 857 patients, 413 were in the laparoscopy group and 444 in the open group. The nearest neighbor matching of propensity score matching method was conducted with 1:1 matching based on tumor location and size between laparoscopy and open group to obtain samples of covariate equilibrium, and the caliper value was 0.04. The t test, χ 2 test and Wilcoxon rank test were used to compare short-term efficacy, and the Kaplan-Meier curve and log rank test were applied to compare long-term outcomes between the two groups. Results:After propensity score matching, laparoscopy group and open group both enrolled 293 cases. The baseline data, including age, gender, tumor location, tumor long diameter, NIH classification, etc. were not significantly different between the two groups (all P>0.05). Compared with the open group, the laparoscopy group had less intraoperative blood loss [<100 ml: 2.9% (155/293) vs. 36.2% (106/293), Z=-12.857, P<0.001], shorter time to postoperative feeding [(4.0±0.2) days vs. (5.3±0.9) days, t=1.505, P=0.003] and to the removal of drainage tube [(4.8±1.0) days vs. (6.5±1.0) days, t=1.847, P=0.008], and shorter postoperative hospital stay [(8.6±0.3) days vs. (10.5±0.3) days, t=4.235, P<0.001]. Subgroups analysis according to anatomical location: (1) Gastric cardia and pylorus: there were no statistically significant differences in perioperative parameters between the two groups (all P>0.05). (2) Stomach base: feeding time after surgery [(4.0±0.2) days vs. (4.5±0.2) days, t=0.512, P=0.038], drainage tube removal time [(5.1±0.4) days vs. (6.4±0.6) days, t=0.517, P=0.044], postoperative hospital stay [(8.0±0.5) days vs. (11.1±0.9) days, t=0.500, P=0.002] were all significantly shorter in the laparoscopy group as compared to the open group, while the differences in other perioperative parameters were not statistically significant (all P>0.05). (3) Lesser curvature of the stomach: the laparoscopy group had less intraoperative blood loss [<100 ml ratio: 58.1% (43/74) vs. 33.7% (25/74), Z=7.632, P=0.034], shorter gastric tube removal time [(2.7±0.2) days vs. (3.2±0.3) days, t=0.503, P=0.007], earlier postoperative passage of gas [(2.8±0.1) days vs. (3.4±0.2) days, t=0.532, P=0.030], earlier postoperative feeding [(3.6±0.2) days vs. (4.3±0.2) days, t=0.508, P=0.020], shorter drainage tube removal time [(4.2±0.4) days vs. (5.7±0.5) days, t=0.508, P=0.020] and postoperative hospital stay [(8.3±0.6) days vs. (10.7±0.3) days, t=0.502, P=0.006] as compared to the open group. (4) Great curvature of the stomach: the laparoscopy group presented less intraoperative blood loss [<100 ml ratio: 52.7% (39/74) vs. 36.5% (27/74), Z=7.681, P=0.032], earlier gastric tube removal [(2.6±0.2) days vs. (3.6±0.2) days, t=0.501, P=0.001], earlier postoperative passage of gas [(2.7±0.2) days vs. (3.4±0.2) days, t=0.501, P=0.016], earlier postoperative feeding [(3.6±0.2) days vs. (4.7±0.2) days, t=0.500, P=0.001], shorter drainage tube removal time [(4.0±0.5) days to (5.9±0.4) days, t=0.508, P=0.002] and postoperative hospital stay [(7.5±0.3) days to (9.5±0.1) days, t=0.500, P=0.001] than the open group. Subgroup analysis according to tumor size: (1) Tumor long diameter 2.0-5.0 cm: the laparoscopy group had earlier passage of gas [(2.9±0.1) days vs. (3.5±0.1) days, t=0.500, P=0.001], earlier postoperative feeding [(4.5±0.1) days vs. (5.0±0.2) days, t=0.501, P=0.013], shorter drainage tube removal time [(4.8±0.3) days vs. (6.0±0.3) days, t=0.511, P=0.008] and postoperative hospital stay [(8.1±0.4) days to (10.1±0.3) days, t=0.513, P=0.001] than the open group. (2) Tumor long diameter 5.1-10.0 cm: in the laparoscopic group, postoperative feeding time [(4.0±0.2) days vs. (4.7±0.2) days, t=0.506, P=0.015], drainage tube removal time [(4.6±0.4) days vs. (6.4±0.5)) days, t=0.501, P=0.004], postoperative hospital stay [(8.2±0.3) days vs. (10.9±0.6) days, t=0.500, P=0.001] were all shorter than those in the open group. No intraoperative and postoperative complications were observed in each group. The 5-year recurrence-free survival rates of the laparoscopy group and the open group were 95.4% and 91.6%, respectively ( P=0.734), and the 5-year overall survival rates were 93.8% and 90.8% ( P=0.691), respectively, and the differences were not statistically significant. Conclusions:In experienced medical centers, laparoscopic surgery for gastric GIST larger than 2 cm is safe and feasible, and can achieve comparable efficacy with open surgery. For gastric GISTs which do not locate in the greater curvature and the anterior wall of the stomach, and whose long diameter is ≤5 cm, laparoscopic surgery does not increase the risk of recurrence and metastasis, and can accelerate postoperative recovery.

Objective To investigate insulin resistance in type 1 diabetes(T1DM)with euglycemic-hyperinsulinemic clamp.Methods Eight cases of newly diagnosed T1DM and 8 cases of newly diagnosed type 2 diabetes(T2DM)were selected.Their insulin sensitivity index(ISI)was evaluated with euglycemic-hyperinsulinemic clamp after 2 week insulin intensive treatment and compared with that of 10 heMthy volunteers(normal control group,NC group).Results Age,BMI,fasting insulin(Fins),fasting C-peptide in the TI DM group were significantly lower than those in the NC group.while waist-to-hip ratio (WHR),systolic blood pressure(SBP),diastolic blood pressure(DBP),TC,TG,LDL-C,HDL-C were not significantly different between the T1DM and NC groups.Age,BMI,WHR,Fins,fasting C-peptide,SBP,TC,TG in the T1DM group were significantly lower than those in the T2DM group.The ISI of the NC,TlDM and T2DM groups were 12.83±1.09,9.95±0.50,3.80±0.20,respectively.There was significant difference among the three groups(P＜0.05).Conclusion The ISI in T1DM Was significantly lower than that in NC group,but higher than that in T2DM.