Nisin is a cationic antimicrobial peptide produced by some lactic acid bacteria. However, expression of nisin resistance protein (NSR) could confer nisin resistance on some non-nisin-producing Lactococcus lactis. To deeply elucidate molecular mechanism underlying NSR-mediated nisin resistance, an NSR mutant with N-terminal 38 amino acid residues deleted (NSR?38) was overexpressed in Escherichia coli by fusion with GST. Purified NSR?38 was obtained through glutathione (GSH) affinity chromatography followed by cleavage of GST tag. Putative proteolytic activity of NSR?38 was determined in vitro against nisin. Antimicrobial activity analysis revealed that nisin lost its bactericidal activity after incubation with NSR?38. Further reversed-phase high performance liquid chromatography (RP-HPLC) analysis indicated that NSR?38 displayed proteolytic activity against nisin, thus inactivating the antimicrobial peptide. The current study paves the way for in-depth functional studies on NSR.

Objective To systematically evaluate the comprehensive effect of subglottic secretion drainage (SSD) on patients with mechanical ventilation (MV) in intensive care unit (ICU). Methods The randomized controlled clinical trials (RCTs) comparing SSD (intervention group) versus non-SSD (control group) in adult patients with MV in ICU was collected through the databases such as the PubMed database of the National Library of Medicine, CNKI, Wanfang database and the Chinese journal of science and technology database (VIP). The subjects were ICU patients with MV, and the retrieval time ranged from January 2006 to December 2016. Two reviewers independently screened the studies according to the inclusive and exclusive criteria, extracted the data, and assessed the quality. Then RevMan 5.3 software was used for Meta-analysis. Sensitivity analysis was performed using Stata 11.0 software. Funnel plot was used to analyze publication bias. Results In the 1004 documents obtained from preliminary screening, a total of 13 studies involving 2052 patients were enrolled after excluding duplicated documents and literature did not meet the inclusion criteria, with 1021 patients in intervention group, and 1031 in control group. Meta-analysis showed that compared with control group, the application of SSD in patients with MV could contribute to the reduction of the incidence of ventilator-associated pneumonia [VAP; risk ratio (RR) = 0.54, 95% confidence interval (95% CI) = 0.46-0.64, P < 0.00001], the duration of MV [mean difference (MD) = -3.29, 95%CI = -4.53 to -2.05, P < 0.00001] and length of hospital stay (MD = -4.27, 95% CI = -7.36 to -1.18, P = 0.007) were shortened, while there was no significant difference in ICU or hospital mortality rate between the intervention group and control group (RR = 0.89, 95%CI = 0.73-1.09, P = 0.25). The sensitivity analysis for studies enrolled in Meta-analysis of MV duration showed that individual research results were stable through step remove of the included literatures and combined calculation of the remaining literature value, suggesting that individual research results were stable, and would not have a significant impact on the overall results. The results of the funnel analysis showed that there was a symmetry in the inclusion studies, and no significant publication bias was found. Conclusions SSD did have effect in reducing the incidence of VAP, shortening the duration of MV and length of hospital stay, while there was no significant effect on reducing mortality rate. Effective use of SSD is an important measure to prevent VAP. It is necessary to objectively evaluate the clinical effect of SSD.

Objective To understand the life quality status of freshmen in higher medical colleges,and discuss the factors influencing the quality of life,in order to improve their life quality,and put forward the countermeasures and suggestions.Methods We randomly selected a higher medical colleges and universities in Yunnan,the grade one students were investigated with SF-36 scale investigation,the data were analyzed by t test and multiple linear regression analysis.Results The quality of life scores (PCS,MCS) of freshmen in this medical college are lower than the national norm,the segmentation in the field of eight only GH is higher than the national norm,and the RP,BP,VT,RE are lower than the national norm.There are six factors into the regression equation of the quality of life:health,insomnia,life pressure,communicating with people,life rule.Conclusions The QOL of freshmen in higher medical colleges and universities is low,relevant departments should be caused to take seriously.To improve the QOL,the government,society,school,personal must make joint efforts in many ways,and take targeted measures.

Objective To study the methodology and effect of auricle reconstruction with prefabricated expanded fascial flap in temporal and parietal area and skin flap in mastoid area, covered on the Medpor support. Methods Thirty cases of congenital vestigial auricle were involved in this study. The operations were divided into two stages: in the stage I,the temporal and parietal superficial fascia flap was cut with a vascular pedicle in the parietal and temporal superficial area, which was implanted under the skin of mastoid, and then both layers of those were expanded at the same time; in the stage II, this fascial skin flap was cut down and covered on the whole Medpor support to rebuild the man-made auricle. Results Thirty cases were successful after following-up for 6 months to 3 years. Their auricle shapes were vivid; their skin color was normal, and it had no any difference from all around skins, or no any appearance of the support. Conclusions With best understanding the biological characteristics of the Medpor support and choosing the suitable procedures and using the prefabricated expanded support, we could minimize the surgical complications in this operation. The results show that this procedure is satisfactory, without any necrosis of flap, swelling of contour, or appearance of the support. The combination of two flaps is the best method for the auricle reconstruction.

Objective:To investigate the current status of the employment quality of public health graduates and feedback from employers.Method:s The questionnaires covering employing fields, coherence between major and employment, ways to find job and feedback from employers were used. A total of 309 bachelor graduates majoring in public health from Grade 2011 to Grade 2016 were selected as study objects via random cluster sampling method. In addition, online and offline synchronization survey were adopted to collect employment data; SPSS 22.0 was used for analyzing the data. Employment quality of graduates from different specialties as well as feedback of employers were compared.Result:s Bachelor graduates in public health had an employment rate of 100%; 19.75% (61/309) graduates in public health changed work place, while the most had a stable job; 50.10% (155/309) graduates had work relatively or fully related to their specialties. Bachelor graduates in public affairs management had a relatively high level of satisfaction in salary, welfare insurance and others (χ 2=18.805, P=0.043). Employers were satisfied with the bachelor graduates generally, but also believed that their professional knowledge and innovation ability should be improved. Conclusion:The overall employment quality of bachelor graduates in public health is good, but there is still room to improve the quality. The overall evaluation for graduates is high, and few organizations consider bachelor graduates of poor quality. In summary, schools should optimize course setting, cultivate comprehensive quality, and strengthen students' humanistic education.

Nosiheptide is a typical thiopeptide antibiotic displaying potent activity toward various drug-resistant strains of Gram-positive pathogens.Although nosiheptide lacks in vivo activity, and good water-solubility with a series of uncontrollable analogues, which may limit its clinical application, glycosylated analogues may overcome problem of low activity and may improve its druggability.In search of novel glycosylated nosiheptide producers, we applied a genome mining strategy that identified Actinoalloteichus sp.AHMU CJ021 that contains all genes required.However, despite the presence of a predicted glycosyltransferase, glycosylated derivatives of nosiheptide were not detected, after following one strain many compounds (OSMAC) strategy and heterologous expression of a regulatory protein NocP.Nevertheless, nosiheptide produced by this strain was remarkably pure, and further experiments were conducted to improve its production by optimization of the culture medium.Under optimal conditions, 58.73 mg/L nosiheptide was produced, representing an almost 6-fold improvement compared to the original fermentation medium.Therefore, we consider Actinoalloteichus sp.AHMU CJ021 a suitable potential candidate for industrial production of nosiheptide, which provides the basis for solving the problem of nosiheptide structural analogues.

Objective:To explore the expression level of exosomal miR-218-5p in the serum of patients with colorectal cancer (CRC) and its correlation with the clinical pathological characteristics, and evaluate its diagnostic efficacy in CRC.Methods:A group of 78 patients with colorectal cancer diagnosed in Tongji Hospital affiliated to Tongji University from October 2016 to October 2018 were selected. Blood was collected before operation and serum was preserved. Forty cases of healthy people in the same period were selected as the control group. ExoQuick kit was used to extract serum exosomes. Transmission electron microscope, NTA and western blot were used to identify the morphology and molecular phenotype of exosomes. MiRNeasy kit was used to extract total RNA in serum exosomes. Real-time fluorescent quantitative PCR (RT-qPCR) was used to detect the expression level of serum exosomal miR-218-5p in each group. CRC patients were divided into high expression and low expression groups using the median relative expression level of miR-218-5p as the cut off value, and the four-square chi-square test (χ 2 test) was used to judge the relationship between miR-218-5p and clinicopathological features. The receiver operating characteristic (ROC) curve was used to evaluate the diagnostic efficacy of miR-218-5p in colorectal cancer. Results:The exosomes in serum were successfully extracted by kit method. The expression level of serum exosomal miR-218-5p in patients with colorectal cancer was significantly lower than that in normal healthy people [0.566(0.364, 0.850) vs 1.054(0.781, 1.709), P<0.001]. The low expression level was significantly better then the correlated with tumor size, TNM stage, lymph node metastasis and depth of invasion (all P<0.05). Receiver operating characteristic (ROC) analysis showed that the area under the curve (AUC) of serum exosomal miR-218-5p for the diagnosis of CRC was 0.827 (95% CI 0.754-0.900), which was significantly better than the conventional tumor marker carcinoembryonic antigen CEA (AUC =0.718, 95% CI 0.626-0.811) and carbohydrate antigen CA199 (AUC = 0.661, 95% CI 0.564-0.758). Conclusions:The down-regulation of miR-218-5p expression in serum exosomes of colorectal cancer patients is associated with a variety of adverse clinicopathological factors, which has the potential to become a diagnostic biomarker for colorectal cancer.

Objective:To investigate the incidence and influencing factors of parastomal hernia in patients with permanent colostomy.Methods:The retrospective cohort study was conduc-ted. The clinicopathological data of 72 patients with permanent colostomy in the Beijing Friendship Hospital of Capital Medical University from January 2016 to June 2020 were collected. There were 50 males and 22 females, aged (66±12)years. Observations indicators: (1) follow-up; (2) analysis of factors affecting the incidence of parastomal hernia; (3) comparison of the incidence of parastomal hernia in patients with different age. Follow-up was conducted using outpatient examination. Patients were followed up once every 12 months after surgery to detect the incidence of parastomal hernia up to September 2021. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was conducted using the t test. Measurement data with skewed distribution were represented as M(range). Count data were expressed as absolute numbers and percentages, and comparison between groups was conducted using the chi-square test. Univariate analysis was conducted using the corresponding statistical methods based on data type. Multivariate analysis was conducted using the Logistic regression model. Kaplan-Meier method was used to draw the parastomal hernia occurrence curve and calculate the incidence rate of parastomal hernia and Log-rank test was used to analyze the incidence of parastomal hernia. Results:(1) Follow-up. All 72 patients were followed up for 23(range, 12?76)months. During the follow-up, there were 31 patients developed parastomal hernia, with the incidence as 20.8%(15/72), 36.1%(26/72) and 43.1%(31/72) at postoperative 1 year, postoperative 2 year and postoperative 5 year, respectively. Of the 31 patients with parastomal hernia, there were 21 cases of type Ⅰ, 3 cases of type Ⅱ and 7 cases of type Ⅲ. Patients with parastomal hernia recovered with conservative treatment. (2) Analysis of factors affecting the incidence of parastomal hernia. Results of univariate analysis showed that age, subcutaneous fat thickness and rectus abdominis thickness were related factors affecting the incidence of parastomal hernia ( χ2=7.98, t=?2.95, 2.02, P<0.05). Results of multivariate analysis showed that age, subcutaneous fat thickness and rectus abdominis thickness were independent factors affecting the incidence of parastomal hernia ( odds ratio=4.07, 3.19, 0.07, 95% confidence interval as 1.46?11.32, 1.43?7.09, 0.01?0.84, P<0.05). (3) Comparison of the incidence of parastomal hernia in patients with different age. Of the 72 patients, there were 37 cases with age <65 years and 35 cases with age >65 years. Of the 31 patients with parastomal hernia, there were 10 cases with age<65 years and all of them with type Ⅰ parastomal hernia, and the incidence of parastomal hernia in postoperative 1 year and postoperative 2 year was 13.5%(5/37) and 27.0%(10/37), respectively. There were 21 cases with age ≥65 years and cases with type Ⅰ, type Ⅱ and type Ⅲ parastomal hernia were 11, 3 and 7, respectively. The postoperative 1 year and postoperative 2 year incidence of parastomal hernia in the 21 cases was 28.6%(10/35) and 45.7%(16/35), respectively. There was a significant difference in the incidence of parastomal hernia between patients<65 years and ≥65 years ( χ2=9.28, P<0.05). Conclusion:Age, subcutaneous fat thickness and rectus abdominis thickness are independent factors affecting the incidence of parastomal hernia.

Objective:To investigate the effect of polypeptide N-acetylgalactosaminaminyltransferase 2 (GALNT2) on the proliferation and apoptosis of human retinal vascular endothelial cells (HRCECs) cultured in high glucose and its possible mechanism.Methods:The small hairpin RNA (shRNA) targeting GALNT2 gene was constructed to interfere with the lentiviral vector and infect HRCECs.HRCECs were divided into blank control group, model group, NC-shGALNT2 group and shGALNT2 group, which were cultured in medium containing 5.5 mmol/L glucose, 25 mmol/L glucose, shGALNT2 negative control virus 25 mmol/L glucose and shGALNT2 knockdown virus 25 mmol/L glucose for 24 hours, respectively.The relative expression of GALNT2 mRNA in the four groups was detected by real-time fluorescence quantitative PCR.The relative expression levels of GALNT2, epidermal growth factor (EGF), EGF receptor (EGFR) and phosphorylated EGFR (p-EGFR) were detected by Western blot.The proliferative values of HRCECs were detected by cell counting kit-8 method.The apoptosis rate of different groups was detected by flow cytometry. Results:The relative expression levels of GALNT2 mRNA and protein were significantly higher in model group than in blank control group, and were significantly lower in shGALNT2 group than in blank control group (all at P<0.05). The cell proliferation value was significantly lower in model group than in blank control group, and was significantly higher in shGALNT2 than in model group and NC-shGALNT2 group (all at P<0.05). The apoptosis rates of blank control group, model group, NC-shGALNT2 group and shGALNT2 group were (4.73±0.26)%, (8.66±0.25)%, (9.26±1.12)% and (5.47±0.18)%, respectively, with a significant overall difference ( F=342.921, P<0.001). The apoptosis rate was significantly higher in model group than in blank control group, and was significantly lower in shGALNT2 group than in model group and NC-shGALNT2 group (all at P<0.05). The relative expression level of EGFR protein was significantly higher and the relative expression level of p-EGFR protein was significantly lower in model group than in blank control group (all at P<0.05). The relative expression of p-EGFR protein was significantly higher in shGALNT2 group than in model group (all at P<0.05). Conclusions:Knocking down GALNT2 can improve the proliferative ability of HRCECs under high glucose culture and reduce apoptosis, which may be related to the activation of EGFR signaling pathway.

Objective:To compare the perioperative complications and prognosis of intracorporeal and extracorporea lileal conduit urinary diversion(ICUD or ECUD)following robot-assisted radical cystectomy(RARC).Methods:The data of 95 patients who underwent RARC treatment in Nanjing Drum Tower Hospital from March 2016 to June 2019 were retrospectively analyzed. Among them, 37 underwent ICUD and 58 underwent ECUD. In the ICUD group, there were 32 males and 5 females, aged(68.0±7.8) years, body mass index (BMI) of (24.1±3.4) kg/m 2, American Society of Anesthesiologists(ASA)score of 1-2 in 4 cases(10.8%), ASA score of 3-5 in 33 cases(89.2%), preoperative hemoglobin of(126.5±14.2)g/L, albumin of(39.0±2.2)g/L, and C-reactive protein of 4.0(2.0-8.5) mg/L. In the ECUD group, there were 53 males and 5 females, aged(67.5±9.0)years, BMI of(24.2±3.6)kg/m 2, ASA score of 1-2 in 16 cases(27.6%), ASA score of 3-5 in 42 cases (72.4%) , preoperative hemoglobin of(129.0±12.4)g/L, albumin (38.2±3.1) g/L, and C-reactive protein of 4.9 (3.1-14.4) mg/L. There was no significant difference in preoperative data between the two groups ( P>0.05). The two groups underwent RARC and pelvic lymph node dissection similarly. The ICUD group underwent a total intracorporeal ileal conduit and the ECUD group underwent extracorporeal ileal conduit with direct vision through a median incision in the lower abdomen.There were 32 cases (86.5%) and 46 cases (79.3%) undergoing expanded pelvic lymph node dissection in the ICUD group and the ECUD group respectively, and the difference was not statistically significant ( P=0.374). The complications were graded according to the Clavien-Dindo grading system. The perioperative complications and prognosis of the two groups were compared. Results:The operation time of the ICUD group and the ECUD group were (430±63) min vs. (410±69) min, respectively ( P=0.163). The estimated blood loss were (435±233) ml vs. (388±277) ml, respectively ( P=0.182). Intraoperative blood transfusion were 10 cases (27.0%) and 12 cases (20.7%)( P=0.475). None of the above differences were statistically significant. Postoperative albumin of the ICUD group and the ECUD group were (31.5±2.4) g/L vs. (31.0±2.8) g/L ( P=0.387), postoperative C-reactive protein were 30.9 (10.4-52.1) mg/L vs.29.5 (14.4-58.5) mg/L ( P=0.655) and postoperative hemoglobin were (110.0±13.8) g/L vs. (113.7±13.4) g/L ( P=0.187). The postoperative feeding recovery were 4(3-5) d vs. 4(3-5) d ( P=0.752) and the postoperative hospital stay were 13(10-19) d vs. 13(11-18) d ( P=1.000). There was no statistically significant difference in perioperative data. The postoperative pathological examination results of ICUD group and ECUD group showed that there were 17 cases (45.9%) vs.19 cases (32.8%) in T a/T 1/Tis stage, 12 cases (32.4%) vs. 18 cases (31.0%) in T 2 stage, 5 cases (13.5%) vs. 19 cases (32.8%) in T 3 stage, 3 cases (8.1%) vs. 2 cases (3.4%) in T 4 stage, respectively and the difference was not statistically significant( P=0.166). The number of lymph nodes removed were (18.2±6.7) vs.(16.5±7.9)( P=0.178) and the number of patients with positive lymph nodes were 6(16.2%) vs.11(19.0%), respectively( P=0.733). None of the patients had positive margins. There was no statistically significant difference in pathological examination overall. There were 14 cases (37.8%) in the ICUD group and 21 cases (36.2%) in the ECUD group experiencing complications within 30 days after operation and the difference was not statistically significant( P=0.872). The complications within 90 days after operation were 14 cases (37.8%) vs. 24 cases (41.4%) respectively and the difference was not statistically significant( P=0.731). Clavien-Dindo grade Ⅲ-Ⅴ complications in the two groups were 1 case (2.7%) vs.1 case (1.7%) respectively, with no significant difference ( P=0.849). One patient in the ICUD group developed an intestinal anastomotic leakage and underwent reoperation for repairing and 1 patient in the ECUD group developed mechanical intestinal obstruction and underwent reoperation. The rate of readmission within 90 days after operation of the ICUD group was lower than that of the ECUD group, but the difference was not statistically significant [3 cases (8.1%) vs. 11 cases (19.0%), P=0.090]. Postoperative follow-up was 13-53 months and the median follow-up of ICUD group and ECUD group were 19 months and 31 months respectively. There was no significant difference in the survival curve between the two groups( P=0.746). The 1-year survival rate was 91.9% in the ICUD group and 91.4% in the ECUD group. Routine re-examination of urinary system CT or B-ultrasound was performed 3 months, 6 months and 1 year after surgery. The incidence of ureteral dilatation/hydronephrosis in the ICUD group was lower than that of the ECUD group, with 4.1%(3 sides) vs. 14.7%(17 sides)( P=0.020). Conclusion:Compared with RARC+ ECUD, RARC+ ICUD does not increase the incidence of complications within 90 days after surgery and may reduce the risk of upper urinary tract dilatation.