Abstract:Objective：To isolate and identify exosomes derived from human umbilical cord mesenchymal stem cells （HUCMCS） and to testify the potential of hemolysis of exosomes. Methods：HUCMSC-derived exosomes were isolated and purified through ultracentrifugation. Western blot and transmission electron microscope were used to identify the characteristic of the exosome. Exosomes were incubated with human erythrocyte suspension to observe the hemolysis. Results：HUCMSCs derived exosomes expressed positive makers of CD9，CD81 and Alix，didn’t express the Golgi Body protein Gm130 as negative marker. The particles size displayed range from 40-120 nm. It can be seen a classical doughnut shape of exosomes through transmission electron microscope. And the exosome derived from HUCMSCs didn’t cause the hemolysis of human red cell. Conclusion：Exosomes secreted by human umbilical cord stem cells possessed classical characteristics of exosomes and had no effects on hemolysis，which provide the experimental basis of potential clinical use of HUCMSC exosomes for drug delivery.

Abstract:Objective：Construct YTH N6-methyladenosine RNA binding protein 1（Ythdf1） knockout mice and study its role during mouse spermatogenesis. Methods：Ythdf1 knockout mice were generated by microinjection of CRISPR/Cas9 into zygote successfully. The role of Ythdf1 in mouse spermatogenesis was detected by immunofluorescence，HE and fertility test. Results：The results of RT-PCR showed that Ythdf1 was expressed in the testis of 1 to 8-week-old male mice. Ythdf1 knockout mice were successfully generated. These knockout mice showed normal spermatogenesis，epididymis morphology and fertility. Conclusion：This study found that deletion of Ythdf1 gene had no effect on spermatogenesis under normal breeding conditions.

Abstract:Objective：To detect the expression of TRAF7 in normal brain tissue and glioblastoma，and further analyze the effect of TRAF7 on proliferation and migration of glioblastoma cells. Methods：Expression of TRAF7 in normal brain tissue and glioblastomas were analyzed in the Chinese Glioblastoma Genome Project（CGGA）Database. The small interfering RNA of TRAF7（si-TRAF7）was transfected into U87 and LN229 glioblastoma cells to downregulate the expression level of TRAF7. The CCK8 assay，colony formation assay and scratch assay were performed to observe the changes of proliferation and migration ability of glioblastoma cells. Results：The expression of TRAF7 in glioblastomas was significantly higher than that in normal brain tissue. Compare to low-expression group of TRAF7，poor prognosis was observed in high-expression group of TRAF7 in glioblastoma patients. Down-regulation of TRAF7 inhibit the proliferation and migration of glioblastoma cells. Conclusion：TRAF7 is highly expressed in glioblastomas，and its expression level is corelated with clinical prognosis in patients with glioblastomas. TRAF7 promotes proliferation and migration in glioblastoma cells.

Abstract:Objective：To detect dynamic expression of Tenascin-X（TNX）and CD34（marker of vascular endothelial cell）and explore the correlation of both in formation of atherosclerotic plaque in apolipoprotein E gene knockout mice（ApoE-/-mice）. Methods：The experimental group of atherosclerotic model was established in ApoE-/- mice fed with a high-fat diet，and the normal C57BL/6 mice fed with normal diet served as the control group. Blood lipid levels were measured and blood samples of aorta were collected at 8 th，12 th，20 th，28 th，and 36 th week after feeding respectively. Oil red O staining and HE staining were used to observe the pathological changes of the aorta，and the quantitative histological and immunohistochemical were analysed meanwhile. Results：The experimental group of low-density lipoprotein（LDL），total cholesterol（TC） levels in each period were higher than the control group（P < 0.05）. With the extension of modeling time，the plaque area and plaque area/lumen area ratio were continually increased in experimental group（plaque area：F=31.473，P < 0.001；plaque area/lumen area：F=178.422，P < 0.001）. The expression quantities of TNX and CD34 increased along with feeding time extendins，and both of them were most expressed at 36 weeks. The TNX and CD34 positive microvessels were highly expressed around the fibrous cap and lipid core，and both were positively correlated（r=0.87，P < 0.001）. However，there were no significant formation of plaques seen in the control group. Conclusion：The expression of Tenascin-X and CD34 increased with the progress of plaque，and the expression sites of Tenascin-X and CD34 in plaque were similar. TNX may be closely related to plaque stability.

Abstract:Objective：To study chronic intermittent hypoxia（CIH）-induced ultrastructural damage of hypoglossal motor nucleus in modeling rat. Methods：Twelve adult male Sprague-Dawley（SD）rats（8 weeks old，weighing 180-200 g）were randomly and meanly devided into two groups（the CIH group and the control group），with 6 rats in each group. The control group was fed in atmosphere environment cabins with 21% oxygen. And the rats of CIH group were fed in low oxygen cabins for 8 hours a day for 35 days with 5% to 21% oxygen. We study the ultrastructural damage of hypoglossal motor nucleus in rat under electron microscope. Results：Electron microscopy showed that the cell membrane of the hypoglossal neurons in the normoxic group was continuous，the nuclear membrane was smooth，the chromatin was homogeneous，and the organelles were abundant. In the CIH group，the cell membrane was discontinuous，the shape of nucleus was irregular，and its membrane was invaginated. There were some areas of edema vacuolization in the neurons . The mitochondria are swollen，and its outer membrane is ambiguous；the Golgi body and the smooth endoplasmic reticulum appear to be swollen and dilated；and lipofuscin is also observed. Conclusion：CIH can induce sublingual nucleus damage in rats，so that a series of ultrastructural changes in the hypoglossal nucleus can be observed under electron microscope.

Abstract:Objective：To investigate the effects of carcinoma-associated fibroblasts（CAFs）on chemoresistance of epithelial cancer cells and the underlying mechanism. Methods：Epithelial ovarian cancer cell Ovcar3 were exposed to cis-diammin-odichloroplatinum（DDP） with various concentrations and different duration，then CAFs cultured with Ovcar3 cell. The apoptosis of Ovcar3 cell was assessed by flow cytometry. The mRNA level of PI3K/AKT/XIAP was detected by real-time PCR. The protein level of PI3K，XIAP，AKT and AKT phosphorylation（p-AKT）was detected by Western blot. Signaling transduction inhibitors，LY294002 was used to block PI3K/AKT signaling pathways. Results：After co-culture，CAFs prevent DDP-induced apoptosis by upregulating the mRNA level and protein levels of PI3K/XIAP（P＜0.05）. In addition，p-AKT was enhanced by CAFs. Remarkably，inhibition of p-AKT by LY294002 can block the effects on DDP-induced XIAP up-regulation. Conclusion：These results demonstrate a novel mechanism by which CAFs regulates apoptosis and the possible involvement of the PI3K/AKT/XIAP survival pathway in chemoresistance of epithelial ovarian cancer cells.

Abstract:Objective：To investigate the efficacy and mechanism of baicalin（BA）inhibiting coxsackie virus B3（CVB3） infection in vitro. Methods：Hela cell viability was measured by CellTiter 96- AQueous single reagent. The virus titer was detected by virus plaque assay. The concentration of cholesterol（CHO）and free fatty acids（FAA）were detected by CHOD-PAP and ACS-ACOD，respectively. The expression levels of fatty acid synthase（Fasn） mRNA and acetyl-CoA carboxylase（ACC） mRNA were detected by RT-PCR. The expression of VP1 protein was detected by Western blot in CVB3 virus. Results：BA had no significant toxic effect on Hela cells at less than 100 μg/mL，but was able to against cytopathy by CVB3 in a dose-dependent manner. The viral titers and CVB3/VP1 expression were significantly reduced by BA treatment in CVB3 infected cells. The levels of CHO and FAA，mRNA of Fasn and ACC were all significantly expressed in CVB3 infected cells，but ware all significantly reduced by BA treatment. Compared with BA treatment group by BSA pretreatment，palmitic acid pretreatment could increase the expression of CVB3/VP1 in Hela cells. Conclusion：BA can against CVB3 infection by regulating cellular lipid synthesis.

Abstract:Objective：To observe the effect of artesunate on pathological changes and inflammatory factors induced by glucocorticoid in guinea pig models. Methods：Thirty male guinea pigs were used 0.05% clobetasol propionate solution continuously on the shaved belly areas for 30 days to establish guinea pig models of steroid-induced dermatitis. They were randomly and equally divided into 5 groups：model groups were intraperitoneal injected with 0.9% sodium chloride solution，treatment groups were intraperitoneal injected with 5，10 and 20 mg/kg artesunate solution separately，glucocorticoid receptor blocking groups were intraperitoneal injected with mifepristone，and 6 guinea pigs only external used with 75% ethanol solution on shaving back as blank control groups. Pathological changes in skin tissue of each group were observed. Enzyme-linked immunosorbent assay（ELISA）was perfomed to detect the content of IL-1 and IL-4 in the serum of each group. The expressions of GRα mRNA and TNF-α mRNA in the skin of each group were detected by RT-PCR. Results：The levels of IL-1 and IL-4 in the serum of model groups were significantly higher than those in the blank control groups and the glucocorticoid receptor blocked groups. The levels of IL-1 and IL-4 in the serum of artesunate groups were lower than those in the model group（P < 0.05）. There was no significant difference between the treatment groups. There was no significant difference in the expression of GRa mRNA in the skin tissues of guinea pigs. The TNF-α mRNA content in the skin tissue of the model group was higher than that in the blank control group and the glucocorticoid receptor blocked group（P < 0.05）. The content of TNF-α mRNA in the skin tissue of the high dose and middle dose group of artesunate was lower than that of the model group（P < 0.05）. There was no significant difference in TNF-α mRNA between the middle dose artesunate group and the high dose arteunate group. Conclusion：Artesunate can inhibit steroid dermatitis in guinea pig models，especially the middle and high dose artesunate，which may associate with IL-1，IL-4 and TNF-α，and the mechanism needs to be further studied.

Abstract:Objective：To explore an induced and culture method for CD4+CD25+Treg cells in vitro，study the effect of Zerumbone about the differentiation and secretion functions of Treg cells and explore the mechanisms included. Methods：CD4+CD62L+T cells were isolated from BALB/c mice spleen and purified with magnetic bead methods. CD4+CD62L+T cells were co-cultured with transforming growth factor（TGF）-beta（5 ng/mL），interleukin（IL）-2（30 μg/mL） for CD4+CD25+Treg polarization．The cultured CD4+CD25+Treg cells were divided into five groups：the normal group；the induced group，which were cultured with the above protocol；Zerumbone（1 μmol/L）group；Zerumbone（10 μmol/L）group； Zerumbone（30 μmol/L）group. Flow cytometry was used to detect the proportion of CD4+CD25+Treg cells. The ELISA method was detected the levels of IL-10. Reverse transcriptase polymerase chain reaction（RT-PCR）was detected the level of IL-10 mRNA and Foxp3 mRNA. Results：The proportion of CD4+CD25+Treg cells cultured with the protocol were significantly higher compared with the normal group（P < 0.05）. The CD4+CD25+Treg cells proportion in Zerumbone（1 μmol/L），Zerumbone（10 μmol/L），Zerumbone（30 μmol/L）groups were significantly increased compared with group model，there is dose dependent（P < 0.05）. The protein level of IL-10 was increased by Zerumbone and that was also dose-dependent. Zerumbone increased the expression of IL-10 mRNA and Foxp3 mRNA（P < 0.05）. Conclusion：Zerumbone can increase the differentiation of splenic CD4+CD62L Zerumbone into CD4+CD25+Treg cells and induce the expressions of IL-10 protein in vitro. The results may be thought the activation of Foxp3 in CD4+CD25+Treg cells.

Abstract:Objective：To explore the role of fatty acid binding protein 4（FABP4）in colon cancer cell invasion. Methods：The expression of FABP4 in a panel of colon cancer cell lines was detected by ELISA and Western blot. Transwell assays were performed to determine invasion of colon cancer cells. The glucose transporter 1（GLUT1）expression in HT29 cell was knockdown by siRNA and glucose uptake. LDH level and lactate production of colon cancer cells were analysed. Results：The expression of FABP4 in medium supernatant and cells was increased in colcon cancer cells HTCC116，SW620 than that in HT29，Colo-2 and SW116 cells. Overexpression of hrFABP4 promoted invasion in HT29 cells，whereas inhibitor of FABP4 impaired the invasion rate of HTC116 cells. The expression of GLUT1 and aerobic glycolysis of colon cancer cells were upregulated by hrFABP4. Knockdown of GLUT1 or inhibition of aerobic glycolysis in HT29 cell abrogated the effect of hrFABP4 on cell invasion. Conclusion：FABP4 may promotes invasion in colon cancer cells through upregulation of GLUT1 and increased aerobic glycolysis.

Abstract:Objective：To analyze the clinical effect of single kidney from pediatric donors ≤ 5 years of age in adult recipients transplantation. Methods：A retrospective study was conducted to analyze the clinical data of nine adult recipients recieving single kidney from pediatric donors from November 2013 to September 2016 in the First Affiliated Hospital with Nanjing Medical University. Results：Six adult recipients received single kidney from five pediatric donors ≤ 5 years of age. For the donors，the median age was 50 months（range，20 to 60 months）and the median weight was 15.5 kg（range，12.0 to 17.0 kg）. Six recipients were female，with their median age 25 years（range，18~31 years），their median weight 43.5 kg（range，34.0~55.0 kg），their median BMI 18.3（range，14.7~22.0）. During the follow-up period，the recipients’ serum creatinine level gradually decreased，and their eGFR increased steadily. The renal function stayed stable within six months to three years after transplantation. The long diameter of the transplanted kidney grew rapidly within 2 weeks after operation（P=0.042），and further growth occurred within 1 year after operation. The 1-year patient/graft survival was 100%. Conclusion：Single renal supply from pediatric donors ≤ 5 years of age is feasible and effective for adult recipients transplantation.

Abstract:Objective：To determine the prognostic relevance of postoperative morbidity in advanced perihilar cholangiocarcinoma（PHC）. Methods：From 2008 to 2017，clinical data of patients undergoing major hepatectomy with caudate lobectomy for PHC were reviewed retrospectively. Severe morbidity was defined as any complication of Clavien-Dindo grade Ⅲ or Ⅳ. Results：A total of 123 patients were enrolled and severe morbidity occurred in 35 patients（28.4%）. The 5-year disease-specific survival and recurrence-free survival for those with and without severe morbidity were：12.9% versus 40.2%（P=0.012）and 0% versus 28.1%（P < 0.001），respectively. Multivariate analysis revealed that severe morbidity independently predicted decreased recurrence-free survival（hazard ratio=1.87，P=0.043）；however，severe morbidity did not emerge as an independent predictor of disease-specific survival. Subgroup analysis of patients stratified by morbidity grade showed similar results，while patients with minor morbidity showed similar survival to those without morbidity. Conclusion：Severe morbidity adversely affects survival outcomes following major liver resection for PHC；thus，optimal preoperative preparation and careful dissection are important to reduce postoperative complications and improve long-term survival.

Abstract:Objective：Observing the expression of visceral fat-specific serine protease inhibitor（Vaspin），cardiac troponin T（cTnT）and N-terminal pro-brain natriuretic peptide（NT-pro-BNP）in acute coronary syndrome（ACS），stable coronary heart disease and control to provide new basis of Vaspin for clinical diagnostic and prognostic evaluation of ACS. Methods：A total of 158 patients with ACS，80 patients with stable coronary heart disease and 90 patients without coronary heart disease were included. The expression of Vaspin was detected by enzyme-linked immunosorbent assay，while the levels of cTnT and NT-pro-BNP were detected at the same time. The expression levels of Vaspin，cTnT and NT-pro-BNP were analyzed and compared in three groups by one-way ANOVA. A 2-year follow-up of clinical outcomes including cardiac death，rehospitalization and revascularization was conducted and logistic analysis was used to evaluate the relationship between Vaspin level and clinical prognosis. Results：The results showed significant difference of Vaspin，cTnT and NT-pro-BNP among three groups（P < 0.01）. The expression level of Vaspin was lowest in ACS group and highest in control group，while the expression level of cTnT and NT-pro-BNP were highest in ACS group and lowest in control group. There was significant negative correlations between Vaspin and NT-pro-BNP or cTnT. Furthermore，lower expression level of Vaspin indicated higher risk of cardiovascular adverse events，such as cardiac death，rehospitalization and revascularization. Conclusion：The expression level of Vaspin in ACS was significantly lower than that in stable and non-coronary heart disease，which was negatively correlated with NT-pro-BNP and cTnT. Vaspin is an independent risk factor for ACS，and the lower expression level of Vaspin，the worse prognosis of patients.

Abstract:Objective：To investigate the effect of fasting plasma glucose（FPG） on the severity of cerebrovascular stenosis in patients with ischemic stroke. Methods：Three hundred and seven patients with ischemic stroke were divided into three groups according to the level of FPG. The clinical features and imaging data of patients were analyzed. Results：With the increase of FPG，the number of diseased vessel，the severity of cerebrovascular stenosis were increased. In patients with age< 60 years，the cerebrovascular stenosis in FPG 5.6-7.0 mmol/L group and FPG > 7.0 mmol/L group was severe than that in FPG < 5.6 mmol/L group. And in patierts with age≥60 years the stenosis in FPG > 7.0 mmol/L group were more serious than that in FPG < 5.6 mmol/L group. Conclusion：Stenosis of cerebrovascular in ischemic stroke increased along with the increase of FPG. The vascular stenosis in patients less than 60 years old with FPG > 5.6 mmol/L or over 60 years old with FPG > 7.0 mmol/L is more serious than that in patients with FPG < 5.6 mmol/L.

Abstract:Objective：To investigate the relationship between serum adropin and carotid atherosclerosis in patients with type 2 diabetes mellitus（T2DM）. Methods：A total of 108 T2DM patients were divided into two groups based on the results of carotid color Doppler ultrasound： 68 with carotid atherosclerosis（T2DM+CAS group）and 40 without carotid atherosclerosis（simple T2DM group），and 60 healthy volunteers were enrolled as normal control（NC group）. General information was gathered. Biochemistry，glycosylated hemoglobin A1c（HbA1c） and fasting insulin（FIns） were detected by clinical laboratory. Serum adropin concentration was measured by enzyme-linked immunosorbent assay. Results：The levels of adropin in T2DM+CAS and simple T2DM were significantly lower than that in NC（P＜0.01）.There was no significant difference of the adropin concentration between T2DM+CAS group and simple T2DM group. Adropin level was negatively correlated with body mass index，triglycerides，fasting plasma glucose，FIns，homeostasis model assessment of insulin resistance（HOMA-IR），HbA1c，high-sensitive C reactive protein and positively correlated with high-density lipoprotein cholesterol（all P＜0.01）. Multiple linear regression analysis revealed that FIns and HbA1c were independent influencing factors of serum adropin（all P＜0.01）. Conclusion：Serum adropin levels were significantly reduced in patients with T2DM，which may be closely related to the pathological process of T2DM by regulating insulin sensitivity，lipid metabolism and inflammatory responses.

Abstract:Objective：To study the association between different types of Modic changes and lumbar disc degeneration，as well as their association with low back pain（LBP） further. Methods：Two hundred individuals with lumbar Modic changes had magnetic resonance imaging（MRI）from Oct to Dec 2016. Lumbar disc degeneration was determined by the Pfirrmann grading system. Intensity of LBP was evaluated via a 10-cm visual analog scale（VAS） through telephone interviews. The distribution of Modic changes and disc degeneration in lower segments（L4/5 and L5/S1 level）along with their associations，as well as their association with LBP，was analyzed. Results：Modic Ⅱ and Ⅱ-Ⅰwere associated with lower disc degeneration（grade 3，P < 0.05）. Modic Ⅰ-Ⅱ was associated with both lower（grade 3）and severe（grade 4）degenerative discs（P < 0.05），while Modic Ⅰcorrelated to severe disc degeneration（grade 4，P < 0.05）. Modic Ⅰ，Ⅱ and Ⅰ-Ⅱ were associated with LBP（P < 0.05）. Significant association between severe disc degeneration（grade 4）and LBP lost in multivariate analyses（P > 0.05）. Conclusion：Severe lumbar degenerative discs are more likely to be accompanied with Modic Ⅰ，while Modic Ⅱ with lower disc degeneration. At the early stage of degenerative process，Modic Ⅱ may change to Modic Ⅰ. Although both causing LBP，lumbar disc degeneration may exert indirect weak influence on LBP through the direct impact of Modic changes.

Abstract:Objective：To evaluate the efficacy and safety of pituitrin injection combined with hysteroscopy and suction curettage for typeⅠcesarean scar pregnancy（CSP）. Methods：From November 2016 to July 2018，21 patients（the experimental group）with typeⅠ CSP in the First Affiliated Hospital of Nanjing Medical University were treated with pituitrin injection combined with hysteroscopic suction curettage，while 83 patients（the control group）with typeⅠCSP were treated with uterine artery embolization（UAE）followed by suction curettage as first-line therapy. The clinical data were analyzed with statistics to compare the efficacy and safety between the two groups. Results：The time of postoperative vaginal bleeding，postoperative hospitalization and the total hospitalization duration was shorter in the experimental group（P < 0.05）.The total hospitalization expenses and the occurrence rate of adverse reactions were lower in the experimental group than the control group（P < 0.05）.There was no significant difference in the treatment success rate，the average operative duration，the intraoperative blood loss，the time when serum β-HCG return to the normal range and the recovery time of menstruation after hospital discharge between the two groups（P > 0.05）. Conclusion：For TypeⅠCSP，both UAE followed by suction curettage and pituitrin injection combined with hysteroscopic suction curettage appear to be nice options. However pituitrin injection combined with hysteroscopic suction curettage possesses an apparent advantage over UAE followed by suction curettage. It may be a priority option for typeⅠCSP.

Abstract:Objective：By comparing with the friction and wear properties of three grown materials and tooth enamel in vitro experiment，to provide a certain experiment basis for choosing the repair materials with the wear resistance close to nature tooth in clinical. Methods：Choosing the veneering porcelain with highly polishing，aierchuang zirconia and machinable compound resin material Lava Ultimate as the experiment group，the tooth enamel was chosen for the control group. Taking the steatite ceramics as resist ware material，simulating the oral environment to do the friction and wear experiment of the two material on the CFT-Ⅰ type material surface properties general-purpose tester. By testing the inspection of surface roughness Ra，surface hardness，abrasion loss and rubbed surface to research the friction and wear properties between abrasion loss and different materials. The statistical analysis was conducted by the method of one-way analysis of variance. Results：Compared with the enamel group，the self-abrasion loss of the three materials and abrasion loss of the resist ware material have statistic difference（P < 0.05），in which the abrasion loss between Lava Ultimate and resist ware material closed to the abrasion loss between tooth enamel and resist ware material most. Conclusion：Compared with veneering porcelain，the zirconia had a better abrasive resistance and lower abrasion of resist ware material. Compared with tooth enamel，the Lava Ultimate had a better abrasive resistance and lower abrasion of resist ware material. Compared with the veneering porcelain and zirconia，Lava Ultimate closed to the tooth enamel more on the aspects of wear-resisting property and abrasion of resist wear material .

Abstract:Objective：To evaluate the effects of ridge preservation in non-molar sites with advanced periodontitis，and to compare the effects of Bio-Oss，Bio-Gene and equal-ratio mixed of both materials. Methods：A total of 26 patients with 32 non-molar regions who were diagnosed with advanced periodontitis at our institution were included. They were classified into three experimental groups and one control group. The experimental groups were grafted with Bio-Oss，or Bio-Gene or the equal-ratio mixed of both materials after the tooth extraction，while the control group did not graft any meterials. Clinical and CBCT parameters were measured before，immediately and 6 months after the extraction. Data statistics used one-way ANOVA and LSD-t analysis. Results：The alveolar ridges of the control group were narrow，while the experimental groups were relatively plump at 6 months after the extraction. The difference of changes of alveolar bone height and width among the control and experimental groups was statistically significant（P＜0.05）. The changes of alveolar bone height，width and density postoperatively of the mixed group were minimal，then was the Bio-Oss group，and last was the Bio-Gene group. The difference among the experimental groups was statistically. Conclusion：Ridge preservation after the extraction was superior in the maintenance of soft and hard tissues. The equal-ratio mixed of Bio-Oss and Bio-Gene was better than either one alone.

Abstract:Objective：To investigate the incidence and location of distolingual canal orifice in permanent mandibular first molars using cone-beam computed tomography（CBCT）and the relevant receiver operating characteristic（ROC）analysis. Methods：A total of 572 mandibular first molars were chosen from 300 patients undergoing CBCT scan in Department of Radiology，Stomatology Hospital of Jiangsu. The number of the distal roots and the root canals of mandibular first molars were recorded by the analysis of the CBCT data using SIMPLANT software，and the distance and angle（∠DBML and ∠DBDL）between the root orifices were measured accordingly. The best diagnostic index for the presence of the distolingual canal orifice in the permanent mandibular first molars was selected by ROC curve，and the critical value was calculated by Youden index. Then，the relationships between the angles and distances formed by the distolingual canal orifice and other root canals orifice were analyzed. Results：The prevalence of two distolingual canals in mandibular first molars was 37.2％（213/572）. The balance test of the classification of distal roots showed no statistically significant difference in gender，age and side（P > 0.05）. ROC analysis showed a high diagnostic accuracy of 0.988 of the area under the ROC curve，which suggested that the ∠DBML could be used as a prediction data to the presence of distolingual canal orifice. The critical value for the diagnosis of distolingual canal orifice of mandibular first molars by ∠DBML is 72.143°. The distolingual canal orifice can be located using the ∠DBDL and ∠DBML angle ratio（∠DBDL=0.551×∠DBML），and the MBO-DLO and MLO-DBO distance ratio（MBO-DLO=1.035 × MLO-DBO）. Conclusion：The angle of ∠DBDL and the distance of MLO-DBO in permanent mandibular first molars could be used clinically for the location of the distolingual canal orifice.

Abstract:Objective：Multi-regional Clinical Trials（MRCTs）are more widely accepted by regulatory authorities from different countries to evaluate the robustness of clinical trial results. FDA requires pharmaceutical companies to conduct two identical multi-regional clinical trials in some therapeutical areas，which is named as twin studies，to ensure that the trials results are repeatable. The paper evaluates two strategies for China to participate MRCT in case twin studies are required. Methods：Data simulation is performed to evaluate these two strategies，and further assess the consistency in efficacy between China and overall population. Results：Accordind to the consistency probabilinies calculate by standard 1 and standard 2，the strategy A is better than the strategy B in the two strategies. Conclusion：Strength and weakness of two strategies are illustrated under different scenarios，and provides corresponding solution and recommendation.

Abstract:Exosomes are nanometer-sized vesicles produced by the fusion of multivesicular bodies and cell membranes which are widely distributed in almost all body fluids such as blood，urine，pleural and peritoneal effusions. As an important role of intercellular communication and genetic material carrier，exosomes play its biological function by stimulating target cells directly through the transfer of various bioactive molecules such as cell membrane receptors，proteins，messenger RNAs（mRNAs）and micro RNAs（miRNAs）. Tumor-derived exosome（TEX）is a type of exosome secreted by tumor cells which not only has the general characteristics of exosomes but also has special features. Studying the effect of TEX will open up a whole new way to diagnosis and treatment of tumor.

Abstract:The occurrence and development of cervical cancer is a complex pathological process. In addition to HPV infection，oncogene activation and inactivation of suppressor genes play an important role in the cancer process. LncRNAs are long RNA transcripts，which are longer than 200 nucleotides and are unable to encode proteins. Some lncRNAs are abnormally expressed in tumors and can be involved in the cellular pathways regulation as oncogenes or tumor suppressor genes，and are closely related to its development and metastasis. There are growing evidences that some lncRNAs are abnormally expressed in cervical cancer cells，and there are various ways to regulate their proliferation，migration and apoptosis. LncRNAs are closely related to tumor size，angiogenesis，FIGO late stage，lymph node metastasis and poor prognosis of cervical cancer. They are important indicators for diagnosis and prognosis，and also are potential therapeutic targets.