Objective To introduce a finger leaf design that is applied to dual layer MLCs.Methods An optimization model was firstly constructed to describe the problem of determining leaf end shapes,and the corresponding problems were then solved by the simplex search method or the simulated annealing technique.Optimal parameters for arc shapes of leaf end projections were obtained,and a comparison was done between optimized MLCs and conventional MLCs in terms of field conformity.The optimization process was based on 634 target fields selected from the patient data base of a treatment planning system.Areas of these fields ranged from 20.0 to 602.7 cm with a mean and its standard deviation of (125.7 ±0.0) cm~2.Results The optimized leaf end shapes projected to the isocenter plane were semicircles.With the finger leaf design,the total area of discrepancy regions between MLC fields and target fields was reduced by 32.3% .Conclusions The finger leaf design improves the conformity of the MLC shaped fields to the desired target fields.

Objective To investigate the correlation between electrogastrogram and gastric emptying in functional dyspepsia (FD) patients.Methods Fifty-one patients with FD were detected by polygraf ID 4-channel electrogastrogram(EGG) analysis system and solid radiopaque marker 5 h after a solid meal.Results 31.4％ (16/51) patients showed delayed gastric emptying(GE),and 72.5％(37/51) patients showed abnormal EGG.The rate of GE between normal EGG patients and abnormal EGG patients had no significant difference(P ＞ 0.05).In patients who had both abnormal EGG and delayed GE,EGG abnormality mainly exhibited dysrhythmia and the dominant frequency of EGG was normal.Some patients also exhibited non enhanced postprandial dominant power.The rate of GE among mild,moderate and severe symptom patients had no significant difference (P ＞ 0.05).The rate of abnormal EGG in severe symptom patients was significantly higher than that in mild and moderate symptom patients [92.9％ (13/14) vs.62.5％ (10/16),66.7％(14/21)] (P ＜0.05).The rate of abnormal EGG in mild and moderate symptom patients had no significant difference (P ＞ 0.05).The rate of GE between Helicobacter pylori (Hp) positive patients and Hp negative patients had no significant difference (P ＞ 0.05).The rate of abnormal EGG in Hp positive patients was significantly higher than that in Hp negative patients [90.0％ (18/20) vs.61.3％ (19/31)] (P ＜ 0.05).The rate of GE and the rate of abnormal EGG had no significant difference between patients with and without active gastritis(P ＞ 0.05).Conclusions The abnormality of EGG plays an important role in the pathogenesis of FD.There is no significant relationship between EGG and GE.The patients with severe symptom and with Hp positive have higher abnormal EGG percentage.Gastritis has no significant correlation with EGG or GE.

Objective To investigate the value of endoscopic submucosal dissection (ESD) and submucosal tunneling endoscopic resection (STER) for the diagnosis and therapy of gastric ectopic pancreas.Methods A total of 86 patients who were suspicion diagnose with gastric ectopic pancreas received ESD or STER in hospital,and the therapeutic effect and safety were followed-up.Results Fifty-four gastric ectopic pancreas patients were definitely diagnosed by postoperative pathology.Of the 54 patients,43 cases were located at the gastric antrum,7 cases were located at gastric fundus and gastric corpus juncture,4 cases were located at gastric corpus.Forty-five cases received ESD,9 cases received STER,rate of completely resection was 88.9％ (48/54),6 cases had a little tissue residual after resection.One case (1.9％,1/54) happened postoperative delay-bleeding,intraoperative and postoperative perforation was not found.During 1-32 months followed up,recurrence was not found.Conclusion ESD could excise the whole lesion to offer an accurate pathology diagnose,meanwhile good for treatment,ESD is an effective and relatively safe method for gastric ectopic pancreas,STER may be a new approach for gastric ectopic pancreas.

Objective To investigate the diagnostic value of tumor marker measurement in biliary juice obtained during endoscopic retrograde cholangiopancreatography (ERCP) in differential diagnosis of suspected biliary-pancrentic diseases.Methods ERCP was performed in patients with suspected biliarypancreatic lesions that could not be diagnosed by routine methods including ultrasonography,MRCP,blood biochemistry and serum tumor marker test,and biliary juice was obtained to measure tumor markers including CEA and CA199.A total of 29 patients with definitive diagnosis were recruited and divided into benign and malignant groups.Serum biochemical findings and tumor markers were compared between 2 groups.The diagnostic value of uhrasonography,EUS,MRCP,ERCP and ERCP combined with biliary tumor markers were also compared.Results There was no significant difference in serum biochemical findings,serum CEA,serum CA19-9 or biliary CA19-9 between 2 groups,while the average biliary CEA in malignant group was significandy higher than that in benign group (P＜0.001).The accuracy of ERCP combined with biliary tumor markers in diagnosing suspected biliary-pancreatic diseases was 69.0%,which was higher than that of ultrasonography (6.9%),MRCP (37.9%) and ERCP (41.4%),respectively.Conclusion The diagnostic accuracy of suspected biliary-pancreatic diseases can be improved through ERCP combined with biliary CEA test,which is helpful in differential diagnosis between benign and malignant lesions.

Objective To use clustering analysis to help physicians detect abnormal parameters in radiotherapy treatment plans and improve the efficiency of plan verification. Methods From 2010 to 2015, 835 breast cancer treatment plans for using 4?field hybrid intensity?modulated radiotherapy from MOSAIQ were collectted. Fractional dose, beam angle, and monitor unit were used as featured parameters of a treatment plan to generate a dataset. The K?means clustering algorithm based on principal component analysis was used to perform a clustering analysis of the dataset and divide the dataset into different clusters. The outliers of clusters were automatically detected based on the distance threshold. The outlier?contained treatment plans were manually verified by physicians to determine the accuracy of clustering analysis in detection of abnormal plans. Results In the clustering analysis, the sample space composed by parameters of treatment plans for breast cancer was divided into 4 clusters, 3 of which had outliers detected. In the targeted treatment plans, 3 plans became outliers because of special target volume and the other 4 plans needed improvement. Conclusions Clustering analysis is effective to help physicians to independently verify treatment plans.

Objective To evaluate the efficacy of itopride hydrochloride combined with alpha-lipoic acid in treatment of diabetic gastroparesis.Methods One hundred and ten patients with diabetic gastroparesis were randomly assigned to two groups.Sixty patients received α-lipoic acid plus itopride (α-lipoic acid 0.6 g intravenously for 14 d plus itopride 50 mg orally t.i.d), and 50 cases received oral itopride only.The clinical symptoms including postprandial abdominal fullness, belching, acid reflux, anorexia, nausea and vomiting were observed;the gastric emptying rate was tested, and plasma motilin and serum ganstrin levels were measured groups, before and after two weeks of treatment.Results The clinical symptom scores of combination therapy group (4.62 ± 3.46 vs.12.26-± 3.43) and control groups (5.43-± 3.65 vs.12.31-± 3.37) were improved after treatment.The overall effective rate of combination group was 91.6％ and that of itopride therapy group was 78.0％ (x2 =4.098, P ＜ 0.05).Gastric emptying rate of combination group [(76.9 ± 9.7) ％ vs.(37.3 ± 10.2) ％] was increased more markedly than that ofitopridegroup[(57.2-± 10.4)％ vs.(36.8-± 11.2)％] (t =10.221, P ＜0.05).Plasma motilin and serum ganstrin levels in combination group [(640.2 ± 64.4) ng/L vs.(554.0 ± 67.6) ng/L, (152.6 ± 20.3)ng/L vs.(96.8 ± 22.2)ng/L] were reduced more markedly than those in itopride group [(636.3 ±66.4)ng/L vs.(589.4 48.3)ng/L, (153.5-± 19.4) ng/L vs.(120.9 ± 19.7)ng/L] respectively (t =3.100, 5.959, all P ＜ 0.05).Conclusion For patients with diabetic gastroparesis, α-lipoic acid and itopride combination therapy can significantly improve symptoms and gastric emptying rate, decrease motlin and gastrin levels;and the efficacy of combination therapy is better than that of itopride monotherapy.

Objective To investigate the influence of epigallocatechin gallate ( EGCG)on reactive oxygen species (ROS) in mouse podocytes exposed to high glucose. Methods Mouse podocytes cultured in high glucose were exposed to different concentrations of EGCG (0.2, 10, 100 μmol/L) or α-tocopherol (0.2 μmol/L) for 6, 12, 24 hours. The viability of podocytes was detected by MTT. The intracellular formation of ROS was detected by confocal microscopy with fluorescent probe CM-H2DCFDA and was measured by fluorescence microscopy. RT-PCR was used to examine the expression of p22phox, p47phox and p67phox mRNA in cultured podocytes exposed to different concentrations of EGCG. Results Intracellular ROS generation was significantly higher in high glucose than that in control conditions (P<0.01). EGCG could significantly inhibit ROS induced by high glucose significantly (P<0.01). EGCG (100 μmol/L) led to an inhibition of the increased production of NADPH oxidase components of p22phox and p67phox mRNA in high glucose (P<0.05). The expression of p47phox mRNA in high glucose was inhibited by EGCG(0.2 μmol/L) and ot-tocopherol(0.2 μmol/L) (P<0.05). Conclusion EGCG can protect cultured mouse podocytes from injury of high glucose by inhibiting ROS formation.

Objective To observe the formation of asymmetric dimethylarginine (ADMA)and the expression of dimethylarginine dimethylaminohydrolase 2 (DDAH-2) of human umbilical vein endothelial cells (HUVECs) stimulated by uric acid (UA), and to explore the role of ADMADDAH axis in the vascular endothelial dysfunction induced by uric acid. Methods HUVECs were cultured in M199 medium supplemented with 10% FBS. Cells were exposed to different concentrations of UA (0, 60, 120 mg/L) for 6 h and 24 h. Under different concentrations and times, the level of ADMA in cell suspension was detected by high performance liquid chromatography (HPLC) technique; the gene and protein expressions of DDAH-2 were detected by RT-PCR and Western blotting; the fluorescence intensity of intracellular 2',7'-dichlorofluorescein (DCF) which represented the productions of ROS was detected by the flow cytometry (FCM). The activity of DDAH-2 in HUVCEs which were exposed to different concentrations of UA (0, 60, 120mg/L) or UA (120 mg/L) +NAC (10 mmol/L) for 24 h was estimated by directly measuring the amount of ADMA metabolized by the enzyme and the role of NAC in the activity was studied.Results The expression of ADMA induced by urid acid was dose-depent and higher at 24 h than that at 6 h in the same dosage (all P＜0.05). The dosage and stimulation time of UA did not have any influence on the expression of intracellular DDAH-2 (all P＞0.05). When HUVECs exposed to UA (120 mg/L) for 24 h, the production of intracellular ROS was significantly increased while the activity of DDAH-2 was decreasesd (all P＜0.05) as compared to 60 mg/L stimulation. This effect could be inhibited by the intervention of anti-oxidant NAC. Conclusions The high UA stimulation on HUVECs can increase the expression of intracellular ROS and inhibit the activity of DDAH-2 which increases the concentration of ADMA by decreasing the degradation of ADMA as well as the formation of NO. DDAH-ADMA axis may participate in the vascular endothelial dysfunction induced by UA.

Objective To study the effectiveness and safety of different endoscopic papillary balloon dilation time in treatment of common bile duct stones. Methods 45 patients with common bile duct stones received ERCP treat﹣ment, and they were randomly divided into short-term and long-term balloon dilatation group, then compared opera﹣tive time, intraoperative and postoperative complication rate, hospitalization days and the total cost of hospitalization between the two groups. Results Short-term group included 22 people, the long term group included 23 people, there were no significant difference in stones' size, number and diameter of common bile duct between the two groups (P> 0.05), however, the success rate of surgery, time of stones' extraction, intraoperative complications and postoperative fistula were significant differences (P<0.05). Conclusion Long-term balloon dilation during ERCP for treatment of common bile duct stones can improve the success rate of stone removal and reduce complications.

Inhibition of human cytochrome P450 (CYP) can lead to drug-drug interactions, resulting in serious adverse reactions.It is therefore crucial to accurately predict the inhibitory power of a given compound against a particular CYP isoform.This study compared 11 machine learning methods and 2 deep learning models based on different molecular representations.The experimental results showed that the CatBoost machine learning model based on RDKit_2d+Morgan outperformed other models in terms of accuracy and Mathews coefficient, and even outperformed previously published models.Moreover, the experimental results also showed that the CatBoost model not only had superior performance, but also consumed less computational resources.Finally, this study combined the top 3 performing models as co_model, which slightly outperformed the CatBoost model alone in terms of performance.