Rhamnolipid biosurfactant is mainly produced by Pseudomonas aeruginosa that is the opportunistic pathogenic strain and not suitable for future industrial development. In order to develop a relatively safe microbial strain for the production of rhamnolipid biosurfactant, we constructed engineered Escherichia coli strains for rhamnolipid production by expressing different copy numbers of rhamnosyltransferase (rhlAB) gene with the constitutive synthetic promoters of different strengths in E. coli ATCC 8739. We further studied the combinatorial regulation of rhlAB gene and rhaBDAC gene cluster for dTDP-1-rhamnose biosynthesis with different synthetic promoters, and obtained the best engineered strain-E. coli TIB-RAB226. Through the optimization of culture temperature, the titer of rhamnolipd reached 124.3 mg/L, 1.17 fold higher than that under the original condition. Fed-batch fermentation further improved the production of rhamnolipid and the titer reached the highest 209.2 mg/L within 12 h. High performance liquid chromatography-mass spectrometry (LC-MS) analysis showed that there are total 5 mono-rhamnolipid congeners with different nuclear mass ratio and relative abundance. This study laid foundation for heterologous biosynthesis of rhanomilipd.
Bacterial Proteins ; genetics ; Batch Cell Culture Techniques ; Decanoates ; Escherichia coli ; metabolism ; Fermentation ; Glycolipids ; biosynthesis ; Hexosyltransferases ; genetics ; Industrial Microbiology ; methods ; Multigene Family ; Promoter Regions, Genetic ; Pseudomonas aeruginosa ; Rhamnose ; analogs & derivatives ; biosynthesis ; Surface-Active Agents ; metabolism

Objective To investigate the supporting policies of assistant general practioner training program (3 + 2 mode) in Shanghai.Methods Total 53 subjects were involved in 15 in-depth interviews and 5 focus group discussions held from October 2012 to October 2013,including 8 graduates from the specialty of country doctor of Shanghai Institute of Health Sciences,12 country doctors,2 leaders of 3 + 2 mode training hospital,5 leaders of rural community health centers,3 leaders of Shanghai Institute of Health Sciences,9 leaders of Commission of Health and Family Planning in Shanghai suburbs,3 leaders of Shanghai Municipal Commission of Health and Family Planning,1 leader of National Health and Family Planning Commission.Results Three leaders of Shanghai Municipal Commission of Health and Family Planning admitted the training program involved multiple departments and there were no unified supporting policies,2 leaders of Commission of Health and Family Planning in Shanghai suburbs thought the enrollment amount should be appropriately controlled.The exploration of social person (non-formal employees)mode was encouraged by the leaders of Shanghai Municipal Commission of Health and Family Planning.Leaders of rural community health centers strongly recommended to increase the selection and withdrawal mechanism to ensure the quality of students and training.Three leaders of rural Commission of Health and Family suggested to enroll student from other provinces.Leaders of rural community health centers and Shanghai Municipal Commission of Health and Family Planning agreed that qualifying as assistant general practioner was an important target of training which should be obtained before graduation.All 3 + 2 mood trainees had a strong expectation to get a bachelor degree at the same time of completing the training.Leaders of Shanghai Municipal Commission of Health and Family Planning and 3 + 2 mode training hospitals proposed to pay attention to the construction of training base and teacher training.About one third of the 3 + 2 mood trainees,graduates from the specialty of country doctor of Shanghai Institute of Health Sciences and country doctors hoped to get more space for development.Leaders of rural community health centers and Shanghai Municipal Commission of Health and Family Planning considered that the qualification of assistant general practioner should be the minimal recruitment for recruitment of new medical personel.Leaders of Shanghai Institute of Health Sciences and 3 + 2 mode training hospital suggested the relevant departments to support the new country doctors in terms of income,promotion policies and so on.Conclusions The supporting policies of the pilot 3 + 2 training in Shanghai are imperfect.It can be improved from organization,management,training implementation and career development.Effective support policies can help to generalize the 3 + 2 training.

Objective To evaluate the effect of hydrogen peroxide (H2O2) on autophagy in melanocytes,and to explore its possible regulatory mechanisms.Methods Normal human melanocytes at exponential growth phase were divided into several groups:blank control group receiving no treatment,positive control group treated with 100 nmol/L sirolimus solution,and experiment groups treated with H2O2 solution at different volume fractions of 10-7-10-3 respectively.After 4-hour treatment,cell counting kit-8 (CCK-8) assay and flow cytometry were performed to evaluate the cellular proliferative activity and detect apoptosis of melanocytes respectively.Acridine orange staining was performed to detect autophagosome formation,transmission electron microscopy to observe ultrastructural changes of autophagosomes,and Western blot analysis to measure the expression of autophagy-specific protein Beclin 1 and microtubuleassociated protein 1 light chain 3B (LC3B).A total of 84 autophagy-related genes were analyzed by RT2 Profiler PCR Array,so as to screen differentially expressed autophagy-related genes.Results After the treatment with H2O2 at different volume fractions of 10-3,5 × 10-4,10-4,5 × 10-5,10-5,5 × 10-6 and 10-6,experiment groups showed significantly decreased cellular proliferative activity,but significantly increased apoptosis rate compared with the blank control group (F =286.95,301.23,respectively,both P ＜ 0.05).With the increase in volume fractions of H2O2,the cellular proliferative activity was significantly gradually decreased (P ＜ 0.05),while the apoptosis rate showed an opposite trend (P ＜ 0.05),except that the 5 ×10-6 H2O2 group showed no significant differences in the apoptosis rate compared with the 10-5 H2O2 group and 10-6 H2O2 group.Acridine orange staining and electron microscopy showed autophagosome formation in the 10-5 H2O2 group,10-6 H2O2 group and positive control group.Western blot analysis revealed that Beclin1 expression and LC3B-Ⅱ/LC3B-Ⅰ ratio were significantly higher in the 10-5 H2O2 group,10-6 H2O2 group and positive control group than in the blank control group (all P ＜ 0.05).RT2 Profiler PCR Array showed significant up-regulation of ATG12,ATG3,ULK1,PIK3CG,PTEN and PIK3C3 genes and significant downregulation of EIF2AK3 gene in the 10-5 H2O2 group,10-6 H2O2 group and positive control group compared with the blank control group.In the 10-5 H2O2 group and positive control group,the mTOR gene was significantly up-regulated,and the ULK2 gene was significantly down-regulated.The 10-6 H2O2 group showed no obvious changes in the expression of mTOR gene,but significant up-regulation of AMPK and JNK1 genes.Conclusion H2O2 at volume fractions of 10-5 and 10-6 can induce autophagy in melanocytes,likely by influencing the expression of some related signaling molecules.

Objective To investigate the clinical characteristics and etiology in infants undergoing colonoscopy in order to improve the understandings of lower gastrointestinal tract diseases and their endoscopic manifestations.Methods The clinical and endoscopic data of the infants aged ≤ 3 years old who underwent conoloscopy at the Department of Gastroenterology,Children's Hospital of Chongqing Medical University,from July 2010 to December 2014,were retrospectively analyzed.A total of 223 children were included,148 male and 75 female.The age range was from 26 d to 3 years old(＜6 months:41 cases;6-12 months:68 cases;1-3 years old:114 cases).Results A total of 235 colonoscopies were performed under deep sedation by single or double manipulators.Cecal intubation was successful in 192 colonoscopies and terminal ileal intubation was completed in 29 colonoscopies,with a high success rate of 94.0％ (221/235 colonoscopies).The main symptoms included hematochezia (124 cases,55.6％),persistent/chronic diarrhea (55 cases,24.7％),hematochezia with chronic diarrhea(22 cases,9.5％),and others(22 cases,9.5％).Of the 223 patients,clear diagnosis were established for 215 children (96.4％),with food protein-induced proctocolitis (FPIPC) (78/223 cases,35.0％),colonic polyps (50/223 cases,22.4％),colitis (29/223 cases,13.0％),antibiotic associated diarrhea (AAD) (19/223 cases,8.5％),FPIPC with AAD (10/223 cases,4.5％).Conclusions Colonoscopy serves as a very important tool for the accurate diagnosis of lower gastrointestinal diseases with hematochezia and/or chronic diarrhea.FPIPC and colonic polyps are the most common causes for hematochezia and/or chronic diarrhea.AAD may be another important cause of chronic diarrhea and bloody stool in infants.Moreover,ghe application of colonoscopy in combination with histopathology can also play an important role in the diagnosis of some rare diseases,such as intestinal tuberculosis,primary intestinal lymphangiectasia,Behcet's disease and primary immunodeficiency disease.

Objective To learn the effects of family supportive supervisors on medical staff turnover intention. Methods The scales of family supportive supervisor behavior scales, work-family conflict scale and turnover intention scale were used in the study. The data were collected from a questionnaire survey of 214 army tertiary hospitals′ medical staff during October to December 2017. Hierarchical regression analysis was used to establish a model to understand the influence of family supportive supervisor behavior, two-way conflict between work and family, using the independent variables, on turnover intention of medical staff. Results The and family supportive supervisor behaviors had a negative explanation to medical staff turnover intention ( β = - 0. 211, P < 0. 01), work interference with family had a positive explanation to it (β = 0. 358, P < 0. 01), family interference with work had an obscure explanation to medical staff turnover intention (β = 0. 104, P > 0. 05). Work interference with family had a partially mediating effect which influenced family supportive supervisor behaviors on medical staff turnover intention. Conclusions Family supportive supervisor behavior, as an organizational support, can effectively alleviate the work interference on family for medical staff and thus minimize their turnover intention.

Objective To evaluate the clinical effect of endoscopic retrograde biliary drainage (ERBD) and endoscopic naso-biliary drainage (ENBD) on hilar cholangiocarcinoma (HACC).Methods The clinical data of 87 patients with HACC,who underwent ERBD and ENBD form January 2010 to January 2016,were retrospectively analyzed.The incidence of postoperative severe cholangitis,biliary obstruction again within 4 weeks,reduction of total bilirubin and survival time were studied.Results There were significant differences between ERBD group and ENBD group on the incidence of severe cholangitis[29.2％ (14/48) VS 10.3％ (4/39),x2 =4.689,P=0.030] and bile duct obstruction in 4 weeks after operation [47.9％ (23/48) VS 23.1％ (9/39),x2=5.710,P =0.017].The total bilirubin within 2 weeks and 4 weeks postoperatively was significantly reduced compared with that before operation (P＜0.05).There was no statistical difference in descend range of total bilirubin between the two groups.There was significant difference between ERBD group and ENBD group in the median survival time [14 weeks (range,0-60 weeks) VS 34 weeks (range,2-96 weeks),x2 =10.101,P=0.010].Conclusion Compared to ERBD,ENBD has certain advantages on palliative care for HACC.

Objective:To deeply understand the pain perception and experience of patients after mixed hemorrhoid surgery, so as to provide reference for taking targeted intervention measures to relieve pain symptoms.Methods:Purpose sampling method was used to conduct semi-structured in-depth interviews with 9 patients with postoperative pain of mixed hemorrhoids admitted to Guilin Hospital of Integrated Traditional Chinese and Western Medicine from February to March 2021, and Colaizzi phenomenological analysis method was used to analyze data and refine themes.Results:The pain perception and experience of patients after mixed hemorrhoid surgery can be summarized into 5 themes: fear of pain, persistent negative thinking about pain, perception of inability to cope with pain, emotional expectation, and expectation of Traditional Chinese Medicine nursing techniques.Conclusions:Patients after mixed hemorrhoid surgery have many burdens and needs in terms of pain experience. Medical staff must establish a complete pain management system for patients after mixed hemorrhoid surgery, aiming at the catastrophic pain experience of patients, correcting their cognitive level of pain management, and satisfying patients Alleviate the need for pain, establish an effective emotional and family support system, improve its pain self-management ability, and promote postoperative recovery.

Objective:To investigate the current situation of early postoperative pain beliefs in patients with mixed hemorrhoids and its influencing factors, and to provide a basis for formulating targeted intervention measures.Methods:Totally 242 postoperative patients with mixed hemorrhoids who were treated in Guilin Integrated Traditional Chinese and Western Medicine were selected by convenience sampling method from January 2020 to January 2021 as the research object. The general information questionnaire, Pain Belief and Perception Scale, Visual Analogue Scale, Positive and Negative Emotion Scale were used to investigate. Multiple linear regression was used to analyze the factors influencing of early postoperative pain beliefs in patients with mixed hemorrhoids.Results:The total score of early postoperative pain belief in patients with mixed hemorrhoids was -21-30 (5.32 ± 2.57) points; the results of multiple linear regression analysis showed that age, education level, anal visual analogue score, and negative emotion scores were main factors affecting their pain beliefs ( r=0.736, P<0.05). Conclusions:Patients with mixed hemorrhoids have negative pain beliefs in the early postoperative period. Patients with advanced age, primary/junior high school, high anal pain intensity, and high negative emotion scores are more likely to have negative pain beliefs. Nursing staff should promptly formulate targeted intervention measures according to the main influencing factors in order to reduce the occurrence of negative beliefs about pain.

Objective:A scoping review of factors influencing eHealth literacy in older adults to inform future research and clinical practice.Methods:Accordance with the scope review methodological framework, research questions were established, and PubMed, Web of Science, Medline, CINAHL, Embase, Cochrane Library, CBM, CNKI, Wanfang, and VIP databases were systematically searched for the timeframe of the search from the time the database was constructed to November 24, 2023.Results:A total of 29 articles were included in the literature, which met the criteria of inclusion exclusion. The main factors influencing eHealth literacy among older adults included sociodemographic factors, disease-related factors, Internet use characteristics, psychosocial factors, healthy aging, and perceived health risks.Conclusions:eHealth literacy in older adults is affected by many complex factors. Most of the measurement tools are universal scales, and there are differences in the results of studies in different groups and regions. Future studies may consider using or developing specific eHealth literacy assessment tools for older adults, and carrying out targeted studies on older adults with different group characteristics.

The pathogenesis of diabetic peripheral neuropathy(DPN)is driven by environmental factors,which can induce epigenetic changes and make it a bridge between environment and gene expression.Hyperglycemia causes changes in DNA methylation,abnormal regulation of enzyme activity involved in his tone modification,and is associated with chromatin structural modification,leading to alterations in DPN gene expression.This article reviews the research progress of epigenetic effects on DPN.