OBJECTIVE To investigate the delayed cytotoxicity effect of chlorpyrifos (CPF) with?drawal on primary hippocampal neurons. METHODS Hippocampal neurons were prepared from SD rat fetuses on the 17th day of gestation. Seven days after culture,neurons were exposed to CPF 10 and 30 μmol · L-1,respectively,for 72 h or for 48 h followed by CPF withdrawal for 24 h. CCK-8 kit and neuronal nuclei(NeuN), 5-bromodeoxyuridine(BrdU) and β Ⅲ tubulin immunofluorescence expression methods were used to evaluate the cell viability. RESULTS Compared with normal control, no significant cytotoxicity was found after CPF 72 h continuous exposure. However,CPF 48 h expo?sure followed by CPF withdrawal for 24 h induced evident cytotoxicity. The amount of BrdU positive and β Ⅲ tubulin positive hippocampal neurons were both decreased significantly(P<0.05),and cell survival and viability reduced after CPF withdrawal. CONCLUSION CPF exposure withdrawal can induce more seriously delayed cytotoxicity than continuous exposure in rat primary hippocampal neurons.

ObjectiveTo investigate the clinical effect of endoscopic sphincterotomy with balloon dilation (ESBD) versus sphincterotomy (EST) alone in the treatment of large common bile duct stones. Methods Foreign databases (including PubMed, CochraneCentral, and Embase) and Chinese databases (including CNKI and Wanfang Data) were searched for randomized controlled trials (RCTs) on the clinical effect of ESBD versus EST in the treatment of large common bile duct stones published up to July 8, 2019. Related data were extracted and RevMan5.3 was used for analysis. Results A total of 13 RCTs with 1926 patients were included, with 973 patients in the ESBD group and 953 patients in the EST group. The meta-analysis showed that there were significant differences between the ESBD group and the EST group in stone clearance rate (odds ratio ［OR］=1.53, 95% confidence interval ［CI］: 1.03-2.29, P=0.04), one-time clearance rate (OR=1.77, 95%CI: 1.06-2.93, P=0.03), rate of use of mechanical lithotripsy (OR=0.40, 95%CI: 0.25-0.63, P＜0.000 1), bleeding rate (OR=0.23, 95%CI: 0.11-0.50, P＜0.001), incidence rate of cholangitis (OR=0.31, 95%CI: 0.12-0.78, P=0.01), incidence rate of early complications (OR=0.59, 95%CI: 0.42-0.84, P=0.003), and time of operation (mean difference=-8.89, 95%CI: -17.56 to -0.22, P=0.04), while there were no significant differences between the two groups in perforation (OR=0.27, 95%CI: 0.05-1.30, P=0.10) and pancreatitis after endoscopy (OR=1.03, 95% CI: 0.66-1.61, P=0.91). ConclusionIn endoscopic treatment of large common bile duct stones, ESBD has several advantages over EST in stone clearance rate, rate of use of mechanical lithotripsy, bleeding rate, incidence rate of cholangitis, and time of operation.

Objective: To compare the efficacy of purse-string skin closure (PSC) and linear skin closure (LSC) in stoma reversal. Methods: Randomized controlled trials (RCT) comparing the use of PSC and LSC during stoma reversal were searched from Embase, PubMed, Web of Science, CNKI net, Wanfang database, VIP Chinese Science and Technology Journal Database. Literature inclusion criteria: (1) randomized controlled trials about comparing PSC and LSC in stoma reversal published publicly; only including English literature; (2) patients undergoing stoma (ileostomy or colostomy) reversal without limitation of age, sex and ethnicity; (3) PSC group receiving the suture of the dermis layer of the skin by purse-string suture, and forming a pore channel in the center of the skin after tightening and knotting, in order to achieve the purpose of secondary healing; the LSC group receiving the suture of the skin with conventional simple interrupted suture; (4) the enrolled literatures needed to include at least one of the following outcome indicators: the primary outcome was the incidence of SSI; the secondary outcome included the operation time, incisional hernia, hospital stay and patient satisfaction. Literature exclusion criteria: (1) duplicate published studies, incomplete studies, reviews, case reports, unpublished literature, retrospective studies, non-RCT. The search time ended on November 15, 2018. The basic information and important outcome indicators of the included articles were extracted. The Cochrane bias risk assessment tool was used to evaluate the quality of the selected literatures. Patient satisfaction was assessed using the following scales: (1) the patient and observer scar assessment scale (POSAS); (2) the body image questionnaire (BIQ); (3) Likert scale; (4) short form 36 (SF-36), version 2; (5) visual analog scale (VAS). Meta-analysis was performed using Review manager 5.3 software provided by the Cochrane Collaboration. Results: A total of 9 randomized controlled trials were included, involving 806 patients with 411 cases in the PSC group and 395 cases in the LSC group. Baseline data such as age, gender, body mass index (BMI), underlying disease, and anesthesia grading were not significantly different between the two groups (all P>0.05). The quality of these nine randomized controlled trials was high. Because the evaluation methods for these studies are not uniform, it is impossible to conduct a meta-analysis of patient satisfaction. However, from the summary results of various studies, the postoperative satisfaction of the purse-string suture group was better than that of the linear suture group. The meta-analysis showed that there was significant difference in postoperative SSI incidence between the PSC group and the LSC group [OR=0.14, 95%CI: 0.08-0.24, P<0.00001], while there were no significant differences in incidence of incisional hernia [OR=0.66, 95%CI: 0.24-1.82, P=0.42], operation time [MD=0.61, 95%CI: -3.17-4.38, P=0.75], and hospital stay [MD=-0.26, 95%CI: -0.82-0.30, P=0.37]. Conclusions PSC can be used for closure of the wound following stoma reversal. Compared with LSC, PSC can significantly reduce the incidence of SSI, and increase patients′ satisfaction.

Objective To evaluate the dynamic contrast-enhanced MRI (DCE-MRI)in detecting experimentally induced testicular ischemia. Methods Thirty healthy male New Zealand rabbits were randomly assigned into 6 groups. There were 5 rabbits in each of the following experimental groups: ( 1 ) Normal control, (2) Sham-operated, (3) ischemia of 3 h group, (4) ischemia of 6 h group, (5) ischemia of 12 h group, (6) ischemia of 24 h group. In all experiment groups, the right testis served as the internal control while the left testis served as the experimental side. DCE-MRI for each animal lasts about 10 minutes. Signal enhanced ratios (SERs) of ROI for both sides of each group were calculated by a computer, and parameters of SERs of 30 s, 75 s, 120 s and maximal SER were used for statistical analysis.Time intensity curves (TICs) were made for two sides of each group via Excel 2003 software and classified into 4 types. Statistical analysis was performed to compare the differences of SERs between left and right testis by two independent Kolmogorov-Smirnov test. Results In group I and 2, significant enhancement was observed on both testes of 10 rabbits. The enhancement decreased gradually with the elongation of ischemia in torsion groups. Three cases of type Ⅰ and 2 cases of type Ⅱ were observed in group 1,5 cases of type Ⅰ in group two, 2 cases of type Ⅰ and 3 cases of type Ⅱ b in group three, 2 cases of type Ⅰ and 2 cases of type Ⅱ b in group four, 5 cases of type Ⅱ b in group five and 5 cases of type Ⅲ in group six were noticed in the left testes. And in TICs of right testes, all cases showed TICs of type Ⅰ except 2 cases of type Ⅱ a in group six. In four torsion groups, the values for SER75 of the left side were 0. 084%, 0. 076%, 0.164% and 0.065%, while the right side were 0.255%, 0.410%, 0.586% and 0.302% (P ＜0.05). The values for SER120 in group three, five and six were 0.221% , 0.158% and 0.059% for the left side, and 0.405%,0.522% and 0.207% for the right side(P ＜0.05). The values for MSER in group three, five and six were 0.217% ,0.164% and 0.072% for the left side, and 0.405%, 0.586% and 0.302% for the right side(P ＜0.05). Conclusion DCE-MRI technique may be useful in the diagnosis of testicular torsion, which shows potential in the clinical application.

Construction and ethanol production effects of SNF4 gene knockout in Saccharomyces cerevisiae were described in this paper. For knockout of SNF4 gene in S. cerevisiae YS2, a PCR-amplified disruption cassette was used, encoding the short flanking homologous regions to the SNF4 gene and Kan(r) as selectable marker. The SNF4 gene disruption cassette was transformed into S. cerevisiae YS2 through LiAc/SS Carrier DNA/PEG. The positive transformants were grown on G418 plates and verified by PCR. The Kan(r) marker was rescued by transforming plasmid pSH65 into positive transformants and inducing expression of Cre recombinase in galactose-containing medium. Lastly, the YS2-deltaSNF4 strain, in which SNF4 allele gene were completely knocked out, was obtained by repeating the same procedure. The result of anaerobic fermentation showed that ethanol production of the SNF4 gene knockout strain had increased by 7.57 percent as compared with the original strain YS2. The experiment indicated ethanol production could be improved significantly with the approach ofSNF4 gene knockout by Cre-LoxP system.
AMP-Activated Protein Kinases ; genetics ; Ethanol ; metabolism ; Fermentation ; Gene Knockout Techniques ; methods ; Mutation ; Saccharomyces cerevisiae ; genetics ; Saccharomyces cerevisiae Proteins ; genetics ; Transcription Factors ; genetics