Objective:To investigate the correlations between the bone mineral densities and biomechanical properties on different layers of the cancellous bone in the proximal tibia.Methods:Quantitative CT was conducted of the 15 specimens of adult male tibia. Based on the artificial destruction levels at the trabecular bone on the tibial plateau, the 15 specimens were randomly divided into 3 groups ( n=5): group A (cancellous bone on the 1.5 cm layer below the articular cartilage), group B (cancellous bone on the 3.0 cm layer under the articular cartilage) and group C (cancellous bone on the 0 to 3 cm range of the subchondral bone). After standing positions were simulated in the 3 sets of specimens, they were connected to a biomechanical testing machine. Twenty-four sites were selected and subjected to a vertical load of 600 N. Strain values and overall displacement values of the specimens were recorded before and after trabecular bone destruction. The correlations were analyzed between bone density and displacement values in groups A and B. The strain values before and after trabecular bone destruction, as well as the overall deformation values of the specimens were compared between the 3 groups. Results:The bone densities of specimens in groups A and B were negatively correlated with the displacement values before and after destruction ( P<0.05). Comparisons of strain values at the 24 sites before and after trabecular bone destruction within 3 groups: There were statistically significant differences in the strain values at 8 sites between before and after trabecular bone destruction in group A ( P<0.05). Of the 8 sites, 6 showed increased strains which were mainly concentrated around the insertion point of the anterior cruciate ligament and the medial tibial plateau. There were statistically significant differences in the strain values between before and after trabecular bone destruction at 3 sites in group B ( P<0.05). The strains at all the 3 sites increased, mainly concentrated behind the surface below the level of destruction. There were statistically significant differences in the strain values at 10 sites in group C between before and after trabecular bone destruction ( P<0.05). Of the 10 sites, 5 showed a decrease in the strain which was concentrated above the destruction plane, and 5 showed an increase in the strain which was concentrated below the destruction plane. The overall deformation values of the specimens in groups A, B, and C were (0.033±0.003) mm, (0.015±0.003) mm, and (0.066±0.007) mm, respectively, showing statistically significant differences between the 3 groups ( P<0.05) as well as between any 2 groups ( P<0.05). Conclusions:Bone mineral density in the cancellous bone of the proximal tibia has some value in assessment of the bone strength. Destruction of the proximal tibial cancellous bone can significantly change the strain distribution on the proximal tibia. The proximal cancellous bone of the tibia plays a key role in stress support and load conduction.

As a generally-recognized-as-safe microorganism, Saccharomyces cerevisiae is a widely studied chassis cell for the production of high-value or bulk chemicals in the field of synthetic biology. In recent years, a large number of synthesis pathways of chemicals have been established and optimized in S. cerevisiae by various metabolic engineering strategies, and the production of some chemicals have shown the potential of commercialization. As a eukaryote, S. cerevisiae has a complete inner membrane system and complex organelle compartments, and these compartments generally have higher concentrations of the precursor substrates (such as acetyl-CoA in mitochondria), or have sufficient enzymes, cofactors and energy which are required for the synthesis of some chemicals. These features may provide a more suitable physical and chemical environment for the biosynthesis of the targeted chemicals. However, the structural features of different organelles hinder the synthesis of specific chemicals. In order to ameliorate the efficiency of product biosynthesis, researchers have carried out a number of targeted modifications to the organelles grounded on an in-depth analysis of the characteristics of different organelles and the suitability of the production of target chemicals biosynthesis pathway to the organelles. In this review, the reconstruction and optimization of the biosynthesis pathways for production of chemicals by organelle mitochondria, peroxisome, golgi apparatus, endoplasmic reticulum, lipid droplets and vacuole compartmentalization in S. cerevisiae are reviewed in-depth. Current difficulties, challenges and future perspectives are highlighted.
Saccharomyces cerevisiae/metabolism* ; Saccharomyces cerevisiae Proteins/metabolism* ; Golgi Apparatus/metabolism* ; Metabolic Engineering ; Vacuoles/metabolism*

BACKGROUND: Nowadays, biological tissue engineering is a growing field of research. Biocompatibility is a key indicator for measuring tissue engineering biomaterials, which is of great significance for the replacement and repair of damaged tissues. METHODS: In this study, using gelatin, carboxymethyl chitosan, and sodium alginate, a tissue engineering material scaffold that can carry cells was successfully prepared. The material was characterized by Fourier transforms infrared spectroscopy. In addition, the prepared scaffolds have physicochemical properties, such as swelling ratio, biodegradability.we observed the biocompatibility of the hydrogel to different adult stem cells (BMSCs and ADSCs) in vivo and in vitro. Adult stem cells were planted on gelatin-carboxymethyl chitosan-sodium alginate (Gel/SA/CMCS) hydrogels for 7 days in vitro, and the survival of stem cells in vitro was observed by live/died staining. Gel/SA/CMCS hydrogels loaded with stem cells were subcutaneously transplanted into nude mice for 14 days of in vivo culture observation. The survival of adult stem cells was observed by staining for stem cell surface markers (CD29, CD90) and Ki67. RESULTS: The scaffolds had a microporous structure with an appropriate pore size (about 80 lm). Live/died staining showed that adult stem cells could stably survive in Gel/SA/CMCS hydrogels for at least 7 days. After 14 days of culture in nude mice, Ki67 staining showed that the stem cells supported by Gel/SA/CMCS hydrogel still had high proliferation activity. CONCLUSION Gel/SA/CMCSs hydrogel has a stable interpenetrating porous structure, suitable swelling performance and degradation rate, can promote and support the survival of adult stem cells in vivo and in vitro, and has good biocompatibility. Therefore, Gel/SA/CMCS hydrogel is a strong candidate for biological tissue engineering materials.

Objective:To investigate the clinical efficacy and prognostic influencing factors of radical surgery for duodenal gastrointestinal stromal tumor (GIST).Methods:The retrospective cohort study was conducted. The clinicopathological data of 741 duodenal GIST patients who under-went radical surgery in 17 medical centers, including 121 cases in Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine, 121 cases in Chinese PLA General Hospital, 116 cases in Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 77 cases in Fudan University Shanghai Cancer Center, 77 cases in West China Hospital, Sichuan University, 31 cases in Guangdong Provincial People′s Hospital, 24 cases in Fujian Cancer Hospital, 22 cases in Fujian Medical University Union Hospital, 25 cases in Shengjing Hospital of China Medical University, 19 cases in Xiangya Hospital, Central South University, 23 cases in Zhejiang Cancer Hospital, 17 cases in Liaoning Cancer Hospital＆Institute, 17 cases in the First Affiliated Hospital of Xiamen University, 15 cases in Sun Yat-sen University Cancer Center, 14 cases in the First Affiliated Hospital of Nanjing Medical University, 14 cases in Zhongshan Hospital Affiliated to Xiamen University and 8 cases in General Hospital of Chinese People′s Liberation Army Air Force, from January 2010 to April 2020 were collected. There were 346 males and 395 females, aged 55(range, 17?86)years. Observation indicators: (1) neoadjuvant treatment; (2) surgical and postoperative situations; (3) follow-up; (4) stratified analysis. Follow-up was conducted using outpatient examination or telephone interview. Patients were followed up once every 3?6 months during neoadjuvant therapy and once every 6?12 months after radical surgery to detect tumor recurrence and survival of patient up to April 2022. Measurement data with normal distribution were represented as Mean± SD. Measurement data with skewed distribution were represented as M(range), and comparison between groups was conducted using the Mann-Whitney U test. Count data were described as absolute numbers or percentages, and comparison between groups was conducted using chi-square test or Fisher exact probability. The Kaplan-Meier method was used to draw survival curves and calculate survival rates. Log-rank test was used for survival analysis. The COX regression model was used for univariate and multivariate analyses. Propensity score matching was done by the 1∶1 nearest neighbor matching method, and the matching tolerance was 0.02. Results:(1) Neoadjuvant therapy. Of the 741 patients, 34 cases received neoadjuvant therapy for 8(range, 3?44)months. Cases assessed as partial response, stable disease and progressive disease before the radical surgery of the 34 cases were 21, 9, 4, respectively. The tumor diameter of the 34 patients before the neoadjuvant therapy and before the radical surgery were 8.0(range, 3.0?26.0)cm and 5.3(range, 3.0?18.0)cm, with the regression rate as 31.9%(range, ?166.7% to 58.3%). (2) Surgical and postoperative situations. Of the 741 patients, 34 cases underwent radical surgery after receiving neoadjuvant therapy, and 707 cases underwent radical surgery directly. All the 741 patients underwent radical surgery successfully, in which 633, 102 and 6 cases received open surgery, laparoscopic surgery and endoscopic treatment, respectively. Of the 633 cases receiving open surgery and the 102 cases receiving laparoscopic surgery, cases with surgical resection range as pancreatoduodenectomy (PD) was 238, and cases with surgical resection range as duodenal limited resection, including duodenal wedge resection, distal gastrectomy, segmental duodenal resection, local resection of duodenal tumor or segmental duodenum combined with subtotal gastrectomy, was 497, 226, 55, 204, 12. Of the 741 patients, 131 cases had post-operative complications including 113 cases with grade Ⅰ?Ⅱ complications and 18 cases with ≥ grade Ⅲ complications of the Clavien-Dindo classification. The duration of postoperative hospital stay of the 741 patients was 13(range, 4?120)days. Of the 707 patients receiving direct radical surgery, 371 cases were evaluated as extremely low risk, low risk, medium risk of the modified National Institutes of Health (NIH) risk classification after surgery, and 336 cases were evaluated as high risk in which 205 cases receive postoperative adjuvant imatinib therapy with the treatment time as 24(range, 6?110)months. (3) Follow-up. All the 741 patients were followed up for 58(range, 7?150)months. During the follow-up, 110 patients had tumor recurrence and metastasis. The 1-, 3-, 5-year overall survival rates and 1-, 3-, 5-year disease-free survival rates of the 741 patients were 100.0%, 98.6%, 94.5% and 98.4%, 90.9%, 84.9%, respectively. The 1-, 3-, 5-year overall survival rates and 1-, 3-, 5-year disease-free survival rates of the 707 patients receiving direct radical surgery were 100.0%, 98.5%, 94.3% and 98.4%, 91.1%, 85.4%, respectively. (4) Stratified analysis. ① Analysis of prognostic factors in patients undergoing radical surgery directly. Results of univariate analysis showed that primary tumor location, tumor diameter, mitotic count, modified NIH risk classification and tumor gene information were related factors affecting the overall survival of 707 patients with primary duodenal GIST who underwent direct radical surgery ( hazard ratio=0.43, 0.18, 0.22, 0.06, 0.29, 95% confidence intervals as 0.20?0.93, 0.09?0.35, 0.10?0.50, 0.03?0.12, 0.09?0.95, P<0.05). The primary tumor location, tumor diameter, mitotic count, modified NIH risk classification were related factors affecting the disease-free survival of 707 patients with primary duodenal GIST who underwent direct radical surgery ( hazard ratio=0.65, 0.25, 0.25, 0.10, 95% confidence intervals as 0.41?1.03, 0.17?0.37, 0.15?0.42, 0.07?0.15, P<0.05). Results of multivariate analysis showed that primary tumor located at the horizontal segment of duodenum, mitotic count >5/50 high power field, tumor gene KIT exon 9 mutation were independent risk factors affecting the overall survival of 365 patients with primary duodenal GIST after removing 342 patients without tumor gene information who underwent direct radical surgery ( hazard ratio=2.85, 2.73, 3.13, 95% confidence intervals as 1.12?7.20, 1.07?6.94, 1.23?7.93, P<0.05). Tumor diameter >5 cm and mitotic count >5/50 high power field were independent risk factors affecting the disease-free survival of 707 patients with primary duodenal GIST who underwent direct radical surgery ( hazard ratio=3.19, 2.98, 95% confidence intervals as 2.05?4.97, 1.99?4.45, P<0.05). ② Effect of postoperative adjuvant therapy on prognosis of high-risk patients of modified NIH risk classification. Of the 336 patients evaluated as high risk of the modified NIH risk classification, the 5-year overall survival rate and 5-year disease-free survival rate were 94.6% and 77.3% in the 205 cases with postoperative adjuvant therapy, versus 83.2% and 64.4% in the 131 cases without postoperative adjuvant therapy, showing significant differences between them ( χ2=8.39, 4.44, P<0.05). Of the 205 patients evaluated as high risk of the modified NIH risk classification who received postoperative adjuvant therapy, there were 106 cases receiving postoperative adjuvant therapy <36 months, with the 5-year overall survival rate and 5-year disease-free survival rate were 87.1% and 58.7%, and there were 99 cases receiving post-operative adjuvant therapy ≥36 months, with the 5-year overall survival rate and 5-year disease-free survival rate were 100.0% and 91.5%. There were significant differences in the 5-year overall survival rate and 5-year disease-free survival rate between the 106 patients and the 99 patients ( χ2=13.92, 29.61, P<0.05). ③ Comparison of clinical efficacy of patients with different surgical methods. Before propensity score matching, cases with primary tumor located at bulb, descending, horizontal, ascending segment of duodenum, cases with tumor diameter ≤5 cm and >5 cm were 95, 307, 147, 34, 331, 252, in the 583 patients receiving open surgery with complete clinical data, versus 15, 46, 17, 5, 67, 16 in the 83 patients receiving laparoscopic surgery with complete clinical data, showing no significant difference in the primary tumor location ( χ2=0.94, P>0.05), and a significant difference in the tumor diameter ( χ2=17.33, P<0.05) between them. After propensity score matching, the above indicator were 16, 39, 20, 8, 67, 16 in the 83 patients receiving open surgery, versus 15, 46, 17, 5, 67, 16 in the 83 patients receiving laparoscopic surgery, showing no significant difference between them ( χ2=1.54, 0.00, P>0.05). Cases with postoperative complications, cases with grade Ⅰ?Ⅱ complica-tions and ≥grade Ⅲ complications of the Clavien-Dindo classification, duration of postoperative hospital stay, the 5-year overall survival rate and 5-year disease-free survival rate were 17, 12, 5, 11(range, 5?120)days, 92.0%, 100.0% in the 83 patients receiving open surgery, versus 9, 7, 2, 11(range, 5?41)days, 91.6%, 97.3% in the 83 patients receiving laparoscopic surgery, showing no signi-ficant difference in postoperative complications, duration of postoperative hospital stay, the 5-year overall survival rate and 5-year disease-free survival rate ( χ2=2.91, Z=3 365.50, χ2=3.02, 1.49, P>0.05) between them. There was no significant difference in complications of the Clavien-Dindo classification between them ( P>0.05). ④ Comparison of clinical efficacy of patients with primary tumor located at the descending segment of duodenum who underwent surgery with different surgical resection scopes. Before propensity score matching, cases with tumor diameter ≤5 cm and >5 cm, cases with tumor located at opposite side of mesangium and mesangium were 71, 85, 28, 128 in the 156 patients with primary tumor located at the descending segment of duodenum who underwent PD with complete clinical data, versus 92, 41, 120, 13 in the 133 patients with primary tumor located at the descending segment of duodenum who underwent duodenal limited resection with complete clinical data, showing significant differences between them ( χ2=16.34, 150.10, P<0.05). After propensity score matching, the above indicator were 28, 13, 16, 25 in the 41 patients with primary tumor located at the descending segment of duodenum who underwent PD with complete clinical data, versus 28, 13, 16, 25 in the 41 patients with primary tumor located at the descending segment of duodenum who underwent duodenal limited resection with complete clinical data, showing no significant difference between them ( χ2=0.00, 0.00, P>0.05). Cases with postopera-tive complications, cases with grade Ⅰ?Ⅱ complications and ≥grade Ⅲ compli-cations of the Clavien-Dindo classification, duration of postoperative hospital stay, the 5-year overall survival rate and 5-year disease-free survival rate were 13, 11, 2, 15(range, 9?62)days, 94.2%, 64.3% in the 41 patients with primary tumor located at the descending segment of duodenum who underwent PD with complete clinical data, versus 9, 8, 0, 15(range, 7?40)days, 100.0%, 78.8% in the 41 patients with primary tumor located at the descending segment of duodenum who underwent duodenal limited resection with complete clinical data, showing no significant difference in post-operative complica-tions, the 5-year overall survival rate and 5-year disease-free survival rate ( χ2=0.99, 0.34, 1.86, P>0.05) between them. There was no significant difference in complications of the Clavien-Dindo classification ( P>0.05) and there was a significant difference in duration of postopera-tive hospital stay ( Z=614.50, P<0.05) between them. Conclusions:The clinical efficacy of radical surgery for duodenal GIST are ideal. Primary tumor located at the horizontal segment of duodenum, mitotic count >5/50 high power field, tumor gene KIT exon 9 mutation are independent risk factors affec-ting the overall survival of patients undergoing direct radical surgery and tumor diameter >5 cm and mitotic count >5/50 high power field are independent risk factors affecting the disease-free survival of patients. There is no significant difference in the short-term efficacy and long-term prognosis between patients undergoing open surgery and laparoscopic surgery. For patients with primary tumor located at the descending segment of duodenum, the duration of postoperative hospital stay is longer in patients undergoing PD compared with patients undergoing duodenal limited resection. For patients evaluated as high risk of the modified NIH risk classification, posto-perative adjuvant therapy and treatment time ≥36 months are conducive to improving the prognosis of patients.

Effective utilization of xylose is a basis for economic production of biofuels or chemicals from lignocellulose biomass. Over the past 30 years, through metabolic engineering, evolutionary engineering and other strategies, the metabolic capacity of xylose of the traditional ethanol-producing microorganism Saccharomyces cerevisiae has been significantly improved. In recent years, the reported results showed that the transcriptome and metabolome profiles between xylose and glucose metabolism existed significant difference in recombinant yeast strains. Compared with glucose, the overall process of xylose metabolism exhibits Crabtree-negative characteristics, including the limited glycolytic pathway activity, which reduces the metabolic flux of pyruvate to ethanol, and the enhanced cytosolic acetyl-CoA synthesis and respiratory energy metabolism. These traits are helpful to achieve efficient synthesis of downstream products using pyruvate or acetyl-CoA as precursors. This review provides a detailed overview on the modification and optimization of xylose metabolic pathways in S. cerevisiae, the characteristics of xylose metabolism, and the construction of cell factories for production of chemicals using xylose as a carbon source. Meanwhile, the existed difficulties and challenges, and future studies on biosynthesis of bulk chemicals using xylose as an important carbon source are proposed.
Biofuels ; Ethanol ; Fermentation ; Metabolic Engineering ; Saccharomyces cerevisiae/genetics* ; Xylose

Objective:To investigate the learning curve of laparoscopic transanal total mesorectal excision (taTME) for rectal cancer operated by one or two surgery teams.Methods:The retrospective cross-sectional study was conducted. Based on the concept of real-world research, the clinical data of 1 458 patients undergoing laparoscopic rectal cancer taTME from 44 medical centers who were registered in the Chinese taTME registry collaborative (CTRC) database from May 2010 to May 2020 were collected. The 1 458 patients were divided into cohorts with one surgery team or two surgery teams according to the operation method. Patients with one surgery team underwent taTME by transabdominal operation and then by transanal operation. Patients with two surgery teams underwent taTME by transabdominal and transanal operation simultaneously with duration of the simutaneous operation time ≥30 minutes. The entire surgical process of patients with two surgery teams is not required to be performed by two surgery teams simutaneously. The clinical data were collected from the medical centers with similar operation amount according to the operation time sequence to analyze the difference between different operation stages and explore the learning curve. The operation time was taken as the parameter to carry out cumulative sum analysis and draw the learning curve of laparoscopic rectal cancer taTME in each medical center. The clinicopathological characteristics of patients from two medical centers with the largest difference in learning curves were analyzed. Observation indicators: (1) screening results of clinical data; (2) clinical data collection of patients with one surgery team; (3) surgical situations of laparoscopic rectal cancer taTME from the one surgery team in different operation stages; (4) learning curve of the one surgery team; (5) clinical data collection of patients with two surgery teams; (6) surgical situations of laparoscopic rectal cancer taTME from the two surgery teams; (7) learning curve of the two surgery teams. The cumulative sum was calculated by the CUSUM=∑i=1nXi-U, where Xi represented the operation time of each taTME, U represented the average operation time of all cases, and n represented the operation number. Fitting process was conducted on scatter plot of learning curves. Taking the apex of learning curve as the boundary, the learning curve was divided into two stages. The abscissa corresponding to the apex of learning curve was the number of operations that needed to be performed to cross the learning curve. Measurement data with normal distribution were represented as Mean±SD. Comparison between two groups was conducted using the t test and comparison between multiple groups was conducted using the ANOVA. Measurement data with skewed distribution were represented as M( P25,P75), and comparison between groups was conducted using the Mann-Whitney U test. Comparison of ordinal data was analyzed using the rank sum test. Count data were analyzed using the chi-square test or Fisher exact probability. Results:(1) Screening results of clinical data:the clinical data of 661 patients from 7 medical centers with one surgery team and two surgery teams were collected. (2) Clinical data collection of patients with one surgery team: the clinical data of 312 patients undergoing laparoscopic rectal cancer taTME from 5 medical centers were collected including 42 cases in the number 2 medical center, 97 cases in the number 20 medical center, 82 cases in the number 33 medical center, 35 cases in the number 37 medical center and 56 cases in the number 39 medical center, respectively. (3) Surgical situations of laparoscopic rectal cancer taTME from the one surgery team in different operation stages: three medical centers including the number 2, number 37 and number 39 medical center with close operation volume provided the clinical data of cases distributed in five operation stages. Among the five operation stages, the proportion of high-quality operation of total mesorectal excision (TME) was ≥17/18, the incidence of postoperative complications was ≤13.3%(4/30) and the incidence of anastomotic leakage was ≤10.0%(3/30). There was no significant difference in the TME quality, postoperative complications or anastomotic leakage among the five operation stages ( P>0.05). There was no significant difference in the operation time among the five operation stages ( χ2=6.950, P>0.05). (4) Learning curve of the one surgery team: the number of operations corresponding to the turning point of learning curve in number 2 and number 20 medical center was 22 and 39, respectively. The number of operations corresponding to the turning points of learning curve in number 33 and number 37 medical center was 15, 66 and 10, 28, respectively. The number of operations corresponding to the turning point of learning curve in number 39 medical center was 20. The overall curve of number 20 medical center was in line with the trend of learning curve and 39 cases of operations was the minimum number needed to cross the learning curve. The biggest difference in learning curve was shown between the number 20 and number 33 medical center. Cases with the gender of male or female, age, body mass index, cases classified as stage 1, stage 2, stage 3 or stage 4 of the American Society of Anesthesiologists (ASA) Classification, cases with neoadjuvant therapy, duration of postoperative hospital stay of the number 20 medical center were 77, 20, (60±10)years, 24 kg/m 2(22 kg/m 2, 26 kg/m 2), 1, 88, 8, 0, 8, 8, 11 days (9 days, 13 days), respectively, versus 51, 31, (64±11)years, 23 kg/m 2(21 kg/m 2, 26 kg/m 2), 0, 35, 43, 1, 31, 16 days (13 day, 21 day) of number 33 medical center, showing significant differences in the above indicators between the two medical centers ( χ2 =6.442, t=-2.265, Z=-2.032, -6.870, χ2 =22.120, Z=-8.408, P<0.05). (5) Clinical data collection of the two surgery teams: the clinical data of 259 patients undergoing laparoscopic rectal cancer taTME from 5 medical centers were collected, including 46 cases in the number 2 medical center, 47 cases in the number 8 medical center, 78 cases in the number 18 medical center, 43 cases in the number 33 medical center and 45 cases in the number 44 medical center, respectively. (6) Surgical situations of laparoscopic rectal cancer taTME from the two surgery teams: four medical centers including the number 2, number 8, number 33 and number 44 medical center with close operation volume provided the clinical data of cases distributed in four operation stages. Among the four operation stages, the proportion of high-quality operation of TME was ≥50.0%(13/26), the incidence of postoperative complications was ≤35.0%(14/40) and the incidence of anastomotic leakage was ≤22.5%(9/40). There was no significant difference in the TME quality, postoperative complications or operation time among the four operation stages ( χ2 =3.252, 4.733, 8.848, P>0.05). There was a significant difference in the incidence of anastomotic leakage among the four operation stages ( P<0.05). (7) Learning curve of the two surgery teams: the number of operations corresponding to the turning point of learning curve in number 2 and number 8 medical center was 28 and 16, respectively. The number of operations corresponding to the turning points of learning curve in number 18, number 33 and number 44 medical center was 12 and 58, 10 and 36, 14 and 36, respectively. The overall curve of number 2 medical center was in line with the trend of learning curve and 28 cases of operations was the minimum number needed to cross the learning curve. The biggest difference in learning curve was shown between the number 2 and number 33 medical center. The age and cases with tumor in stage T0 and (or) Tis, stage T1, stage T2, stage T3 or stage T4 of the T staging of the number 2 and number 33 medical center were (60±12)years, 3, 1, 9, 11, 20 and (65±10)years, 2, 3, 22, 15, 0, respectively, showing significant differences in the above indicators between the two medical centers ( t=-2.280, Z=-4.033, P<0.05). Conclusion:Thirty-nine cases of operations was the minimum number for the one surgery team to cross the learning curve of laparoscopic rectal cancer taTME and 28 cases of operations was the minimum number for the two surgery teams to cross the learning curve of laparoscopic rectal cancer taTME.

The simultaneous electrochemical determination of myricetin and rutin remains a challenge due to their indistinguishable potentials. To solve this problem, we constructed a ternary platinum nanoparticle, reduced graphene oxide, multi-walled carbon nanotubes (Pt@r-GO@MWCNTs) nanocomposite via a facile one-pot synthetic method. Under the optimized conditions, the ternary Pt@r-GO@MWCNTs nanocomposite exhibited good electrocatalytic activity toward myricetin and rutin via solid phase extraction and excellent performance for the simultaneous determination of myricetin and rutin. The oxidation peak current of myricetin was proportional to its concentrations in the range of 0.05-50μM with a detection limit of 0.01μM (S/N = 3). The linear range for rutin was 0.05-50μM with a detection limit of 0.005μM (S/N = 3). The ternary nanocomposite sensor also exhibited good reproducibility and stability, and was successfully used for the simultaneous determination of myricetin and rutin in real orange juice samples with recoveries ranging between 100.57％and 108.46％.

An ultrasensitive electrochemical sensor based on polydopamine/carboxylic multi-walled carbon nano-tubes (MWCNTs-COOH) nanocomposites modified glassy carbon electrode (GCE) was presented in this work, which has been developed for highly selective and highly sensitive determination of an anti-microbial drug, metronidazole. The preparation of polydopamine/MWCNTs―COOH nanocomposites/GCE sensor is simple and possesses high reproducible, where polydopamine can be coated on the surface of MWCNTs―COOH via a simple electropolymerization process. Under optimized conditions, the proposed sensor showed ultrasensitive determination for metronidazole with a wide linear detection range from 5 to 5000μmol/dm3 and a low detection limit of 0.25μmol/dm3 (S/N = 3). Moreover, the proposed sensor has been successfully applied for the quantitative determination of metronidazole in real drug samples. This work may provide a novel and effective analytical platform for determination of me-tronidazole in application of real pharmaceutical and biological samples analysis.

The teaching team of medical functional sciences in Fudan University carried out exper-imental courses targeting problem-based designing and reformed the present teaching system. These experi-mental courses gave up the traditional teacher-based teaching method and guided students to learn knowledge and understand theories independently. At the same time, students could discuss the problems thoroughly, design the experimental plans and verify their hypothesis. This teaching method combines PBL, flipped classes, experimental designs and statistics analysis, which could provide experience for the education of medical functional sciences in medical colleges.

Objective To analyze the dTP value in the patients with coronary heart disease (CHD) complicating diabetes mellitus (DM) and its relationship with major adverse cardiovascular events (MACE) and rehospitalization.Methods Two hundreds and seventy CHD patients were selected as the research subjects,including 136 cases of non-MD and 134 cases of DM.Their clinical condition was recorded.The indicators such as height,body mass,blood pressure and heart rate were measured.ECG,echocardiography,coronary angiography and other examiantions were carried out.The various indicators were detected.11-dh-TXB2 and 6-k-PGF1a levels were detected in the two groups and then dTP value was calculated.The 1-year follow-up was performed,MACE and rehospitalization were recorded.Epdate software was used for building a database and SPSS 17.0 software was applied for conducting the statistical analysis.Results The dTP level in the f non-DM and DM patients were 1.8 ± 0.6 and 2.0 ± 0.7 respectively,the difference was statistically significant (P＜ 0.05).For the non-DM CHD group,hs-CRP,systolic blood pressure,diastolic pressure,lesions number and severe lesions number were correlated with dTP level(P＜0.05).For the complicating DM CHD group,hs CRP,blood glucose,CHO level,lesions number and severe lesions number were correlated with dTP level(P＜0.05).After 1-year follow-up,MACE had 33 cases (24.3％) in the non-DM group and 44 cases (32.8％) in the DM group respectively,the difference was not statistically significant (P＞0.05).The rehospitalized cases had 12 cases (8.8％) in the non-DM group and 24 cases (17.9 ％).in the DM group respectively,the difference was statistically significant (P＜ 0.05).The dTP levels of MACE occurrence and non-MACE occurrence were 2.3 ± 0.8 and 1.8 ± 0.6 respectively,the difference was statistically significant (P＜0.05).The dTP levels of rehospitalized patients and non-rehospitalized patients were 2.4 ± 1.0 and 1.9 ±-0.6 respectively,the difference was statistically significant(P＜0.05).Conclusion The dTP level in the patients with CHD complicating DM is significantly increased,suggesting that platelet is obviously activated,moreover higher dTP level increases the risk of MACE and rehospitalization.So the anti-platelet therapy should be strengthened.