Objective Studies have shown that low concentrations of nicotine can promote neovascularization and promote wound healing.This article aimed to investigate the influence of low concentration collagen membrane slow-release system on the hard palate trauma of rats.Methods Using poly(lactic acid-co-glycolic acid) (PLGA) copolymer as carrier materials, low concentration nicotine sustained-release particles were prepared by emulsion evaporation method (w/o/w), using collagen membrane as the brace and establish a low concentration collagen membrane system.48 Wistar rats were divided into experimental group and blank group, 3 mm diameter circular wound was made in the forepart palate.Low concentration of nicotine collagen membrane sustained-release particle system and blank collagen membrane (control) were sutured on the wound with 6-0 absorbable thread.Then, observed the wound healing of 0, 3, 7, 10 days and compared the healing differences between each groups.Results Under the electron microscope, the nicotine sustained-release particles were circular, similar size with rough surface, the average diameter were 3.0±0.2μm, the encapsulation efficiency and drug loading rate was 50.2% and 4.12% respectively.In vitro, nicotine sustained-release particles released much more nicotine on the first day, less on the second day, tends to stable and fluctuate within a certain range from the third day on, and declined sharply after about 10 days, nicotine concentration from 3rd to 10th day was fluctuate within 10-5-10-4mol/L.Postoperative wound healing, no significant difference in 3 days(P>0.05), after 7 days, the wound healing of experimental group significantly greater compared with the control (P=0.015).The wound was healed in 10 days after operative, there was no significant difference between two groups(P>0.05).The epithelial proliferation in the experimental group was significantly greater than that in the blank group, there were many fibroblasts, inflammatory cells and new capillaries, the epithelial process is short, the submucosa is loose, and a large number of collagen fibers are produced.The lamina propria is closely connected with the periosteum, and the wound is healed Conclusion Low concentration of nicotine sustained-release particles collagen membrane system may promote wound healing in the hard palate mucosa of rats.

Objective To evaluate Roux-en-Y gastric bypass operation on carbohydrate and lipid metabolism in type 2 diabetes mellitus patients with BMI range of 24 -29. Methods Thirty seven cases of type 2 diabetes mellitus patients undergoing Roux-en-Y gastric bypass operation were studied. Body mass index (BMI), glycosylated hemoglobin ( GHbAlc), fasting glucose ( FPG), fasting insulin (FIns) and C-peptide( FC-p), HOMA-IR, oral glucose tolerance (OGTT) including 2 hour insulin (2hIns) and C-peptide (2hC-p) , plasma levels of total cholesterol (TC), triglycerides(TG), high density lipoprotein( HDL-c)and low density lipoprotein ( LDL-c) were measured preoperatively and on 3 months, 6 months, later postoperatively. Result There was no statistically significant difference between BMI values measured preoperatively and postoperatively (P>0. 05 ). Serum levels measured in pre-operative and third and sixth post-operative months were: FPG (8. 8 ± 0. 9, 7. 0 ± 2. 0, 6. 3 ± 0. 6, P<0. 01) ( mmol/L) , GHbAlc (8.2±1.2, 7.0±0.8, 6.2±0.7, P<0.01)(%), FIns(10. 6 ±1. 2, 9.0±0.9, 9.0±0.8, P<0.05)(mU/L), FC-p(1.9±0.5, 1.2 ±0.6, 1.2 ±0.4, P<0. 01) (nmol/L), TG(3.3 ±0.8, 2.7 ±0.9,2.6±0.7, P<0.05)(mmol/L), TC(6.5±1.8, 4.6±0.9, 4.2 + 1.0, P<0. 05) (mmol/L)and LDL-c (3. 6 ±1.2, 2. 8 ±0.8, 2. 7 ±0.2, P<0.01) (mmol/L), 2 hour glucose after OGTT(2hPG) (18. 6 ±3.0, 12.7 ±2.3, 11.4±2.0, P<0. 01) (mmol/L), HOMA-IR(3. 2 ± 1. 7, 2.6±1.6, 2. 5 ±1.3, P<0. 05). Postoperative levels of HDL-c (1. 2 ± 0. 1, 1. 4 ± 0. 4, 1. 4 ± 0. 2, P<0. 01) ( mmol/L) , 2hIns (17. 2 ±3.4, 26. 3 ±4.7, 28. 6 ±4.1, P<0. 01) (mU/L)and 2hC-p(4. 2 ± 1. 0, 6. 3 ± 1. 5, 6. 2 ± 1.4,P<0. 01 ) ( nmol/L) were significantly higher than that of the pre-operative values ( P<0. 01 ).Conclusions Roux-en-Y gastric bypass significantly improves the metabolism of carbohydrate and lipid in type 2 diabetes patients with BMI 24-29, and the effects are not associated with weight loss.

Objective:To construct the siRNA expression vector of focal adhesion kinase(FAK) gene and inhibit the expression of FAK gene in tongue cancer cell line Tca8113 by RNA interfering technique. Methods:According to the encoding sequence of FAK mRNA, two pieces of oligonucleotide sequences were designed and synthesized. The annealed oligonucleotide fragments were subcloned into pGCSilencerTM-U6/Neo siRNA expression vector. After being identified by restriction enzyme method, the recombinant pSilencer-FAK plasmids were transfected into Tca8113 cells. The transfected cells were selected by G418 method. Immuocytochemistry and Western blotting were used to evaluate FAK gene silencing efficiency. Results:The oligonucleotide fragments were correctly inserted into pGCSilencerTM-U6/Neo vector. FAK expression of the transfected cells was significantly down-regulated by pSilencer-FAK. Conclusion:The siRNA expression vector of FAK is successfully constructed and FAK expression of Tca8113 cells can be inhibited by RNA interfering technique.

Objective During the rapid expansion of postgraduate education,it is meeting more and more conflicts between enroll-ment scale and cultivation quality.The construction of a cultivation quality assurance system for postgraduates becomes an urgent task in the new situation.Methods The data was analyzed with SPSS 24.0,based on the anonymous review results of postgraduates'disserta-tions by a three-A stomatological hospital during 2022-2023.Results The results showed that the overall evaluation of anonymous dis-sertation opinions in 2022 was better than that in 2023,and the passing rate of anonymous dissertation evaluation of doctoral students was higher than that of master students.Irregular forms of composition,low research workload,and insufficient innovation were found in failed postgraduates'dissertations.Conclusion Strengthening the management of study style education and training process,and ex-ploring cultivating mode of overlapping subjects,are necessary to improve the construction of cultivation quality assurance system of postgraduates.