Objective To detect gene mutations associated with dapsone-,rifampicin-and ofloxacinresistance in lesions of patients with recurring or treatment-resistant leprosy collected from 2010 to 2011.Methods Clinical data and lesional specimens were collected during 2010-2011 from patients with recurring or treatment-resistant leprosy who were diagnosed and reported by provincial centers for leprosy control.Mycobacterium leprae DNA was extracted from the specimens and subjected to PCR for the amplification of folP1,rpoB and gyrA genes.The PCR products were directly sequenced and BLAST program was used to compare the sequence of isolated strains with the reference sequence in GenBank.Results Twenty-four patients were enrolled in this study,including 13 with recurring leprosy and 11 with treatment-resistant leprosy.Twenty-one patients showed positive PCR results in all the three regions.Of these PCR-positive specimens,3 from 1 patient with recurring and 2 patients with resistant leprosy harbored a point mutation,acc (threonine)→gcc (alanine),at codon 53 in the floP1 gene,1 from a patient with recurring leprosy harbored a missense mutation,gat (aspartic acid) → aac (asparagine),at codon 441 in the rpoB gene.Conclusions Mutations are detected in the folP1 and rpoB genes,which are associated with the resistance to dapsone and rifampicin respectively,but not in the ofloxacin resistance-associated gyrA gene,in Mycobacterium leprae isolates from patients with recurring or treatment-resistant leprosy.

Objective:To analyze the interim clinical efficacy of laparoscopic and open distal gastrectomy for gastric cancer in elderly patients.Methods:The prospective randomized controlled study was conducted. The clinicopathological data of 102 patients aged ≥65 years who underwent distal gastrectomy for gastric cancer in the Nanfang Hospital of Southern Medical University from September 2014 to May 2018 were collected. After excluding 6 patients, 96 patients were finally included. Based on random number table, patients were allocated into two groups. Patients undergoing laparoscopic distal gastrectomy were allocated into laparoscopic group, and patients undergoing open distal gastrectomy were allocated into open group, respectively. Obser-vation indicators: (1) grouping situations of the enrolled patients; (2) intraoperative situations; (3) postoperative situations; (4) follow-up. Follow-up using outpatient examination and telephone interview was conducted to detect complications in the postoperative 30 days up to July 2018. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was analyzed using the t test. Measurement data with skewed distribution were represented as M( P25, P75) or M(range), and comparison between groups was analyzed using the Mann-Whitney U test. Count data were described as absolute numbers or percentages, and comparison between groups was analyzed using the chi-square test. Comparison of ordinal data was analyzed using the non-parameter Mann-Whitney U test. Results:(1) Grouping situations of the enrolled patients: a total of 96 patients were selected for eligibility. There were 66 males and 30 females, aged from 65 to 85 years, with a median age of 69 years. There were 49 of 96 patients in the laparoscopic group and 47 patients in the open group. (2) Intraoperative situations: patients in the two groups underwent distal gastrectomy successfully with D 2 lymphadenectomy, without intra-operative conversion to laparotomy. The volume of intraoperative blood loss and surgical incision length were 50 mL(50 mL,100 mL) and (7.1±1.7)cm for the laparoscopic group, respectively, versus 100 mL(100 mL,200 mL) and (19.1±1.7)cm for the open group, showing significant differences between the two groups ( Z=?3.779, t=?34.880, P<0.05) . (3) Postoperative situations: the number of lymph node dissected, time to postoperative initial out-of-bed activities, time to postoperative first flatus, time to postoperative first liquid food intake, time to postoperative first semi-liquid food intake, time to drainage tube removal, duration of postoperative hospital stay were 49(35,62), 1.9 days(1.3 days,2.9 days), 2.6 days(2.2 days,2.9 days), 3.4 days(2.7days,4.0 days), 5.9 days(4.7 days,7.7 days), 4.9 days(3.5 days,6.8 days), 7.7 days(6.7 days,8.9 days) for the laparoscopic group, respectively, versus 40(27,51), 2.5 days (1.8 days,3.3 days), 2.6 days(2.2 days,2.9 days), 3.9 days(2.9 days,5.7 days), 4.9 days(3.9 days, 5.9 days), 6.3 days(4.7 days,8.9 days), 8.7 days(6.9 days,11.7 days), showing significant differences between the two groups ( Z=?2.354, ?2.210, ?2.743, ?2.474, ?2.906, ?2.503, ?2.359, P<0.05). (4) Follow-up: patients in the two groups received 30 days of follow-up. During the follow-up, 8 patients in the laparoscopic group had postoperative complications, including 1 case with Clavien-Dindo grade Ⅰ complications, 7 cases with Clavien-Dindo grade Ⅱ complications, and no patient with Clavien-Dindo grade Ⅲ complications. Thirteen patients in the open group had postoperative complications, including 2 cases with Clavien-Dindo grade Ⅰ complications, 10 cases with Clavien-Dindo grade Ⅱ complications, and 1 case with Clavien-Dindo grade Ⅲ complications. There was no significant difference in the above indicators between the two groups ( χ2=1.135, 1.973, 1.054, P>0.05). The overall complication rate was 16.3%(8/49) and 27.7%(13/47) for the laparoscopic group and open group, respectively, showing no significant difference between the two groups ( χ2=1.803, 99.7% confidence interval as ?∞ to 2.4%, P>0.05). The upper limit of 99.7% confidence interval was less than non-inferiority level of 15%, interim analysis of which showed that the complication rate of the laparoscopic group was non-inferior to the open group. Conclusion:For elderly patients undergoing laparoscopic or open distal gastrectomy for gastric cancer, laparoscopic surgery does not increase intraoperative or postoperative complications, and has advantages of minimally invasiveness, fine operation, quicker recovery, and shorter hospital stay. Registry: this study was registered at clinicaltrials.gov in United States, with the registry number of NCT02246153.

OBJECTIVE: To investigate whether DNMT1 protein induces retinoblastoma proliferation by silencing MEG3 gene. METHODS: Two retinoblastoma cell lines (HXO-RB44 and SO-RB50) and a normal human retinal pigment epithelial (RPE) cell line were transfected with the plasmid pcDNA-DNMT1 or si-DNMT1 for up-regulating or interference of DNMT1 expression, and with pcDNA-MEG3 or si-MEG3 for up-regulating or interference of MEG3 expression. Western blotting was used to detect the changes in the expression of DNMT1 protein in the transfected cells, and CCK-8 and EdU assays were used to detect the changes in cell proliferation. Real-time quantitative PCR (qRT-PCR) was performed to detect MEG3 expression in SO-RB50 and HXO-RB44 cells after transfection, and the methylation level of MEG3 gene promoter after interference of DNMT1 expression was detected using methylation-specific PCR. RESULTS: SO-RB50 and HXO-RB44 cells showed significantly increased expression of DNMT1 protein as compared with normal RPE cells ( < 0.05). In HXO-RB44 cells, transfection with pcDNADNMT1 resulted in significantly increased expression of DNMT1 protein, enhanced cell proliferation ability, and significantly reduced expression of MEG3 ( < 0.05). In SO-RB50 cells, transfection with si-DNMT1 significantly reduced the expression of DNMT1 protein, suppressed the cell proliferation, and increased MEG3 expression ( < 0.05). Interference of DNMT1 significantly reduced the methylation level of MEG3 gene promoter. After reversing the regulatory effect of DNMT1 on MEG3 gene, DNMT1 protein showed significantly weakened ability to regulate retinoblastoma cell proliferation ( < 0.05). CONCLUSIONS In retinoblastoma cells, the up-regulation of DNMT1 protein induces promoter methylation and inactivation of MEG3 gene and eventually leads to abnormal cell proliferation.