Bacterial multi-drug resistance (MDR) is a global challenge in the fields of medicine and health, agriculture and fishery, ecology and environment. The cross-region spread of antibiotic resistance genes (ARGs) among different species is one of the main cause of bacterial MDR. However, there is no effective strategies for addressing the intensifying bacterial MDR. The CRISPR-Cas system, consisting of clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR associated proteins, can targetedly degrade exogenous nucleic acids, thus exhibiting high application potential in preventing and controlling bacterial MDR caused by ARGs. This review briefly introduced the working mechanism of CRISPR-Cas systems, followed by discussing recent advances in reducing ARGs by CRISPR-Cas systems delivered through mediators (e.g. plasmids, bacteriophages and nanoparticle). Moreover, the trends of this research field were envisioned, providing a new perspective on preventing and controlling MDR.
Anti-Bacterial Agents ; Bacteriophages/genetics* ; CRISPR-Cas Systems ; Drug Resistance, Bacterial/genetics* ; Plasmids/genetics*

OBJECTIVE:To determine the median effective dose (ED50) of propofol with single intravenous injection in alcohol dependence or withdrawal model rats,and to observe the anaesthetic effect of 2-fold ED50 propofol. METHODS:Fifty SD rats were divided into drinking group(n＝23)and control group(n＝27)based on whether the consumption of alcohol was greater than 3.0 g/(kg·d). Drinking group continued to drink freely and intermittently to establish alcohol dependence model. Control group was only given drinking water for ethanol elution 16 rats were randomly selected from each group to determine ED50 of propofol with single intravenous injection by sequential method,and initial dose was 6.02 mg/kg. After eluting for a week,alcohol dependence rats stopped drinking for 24 hours and had alcohol withdrawal symptoms to establish alcohol withdrawal model. ED50 of propofol in alcohol withdrawal group and control group were determined with same method. After eluting for a week,anaesthetic effect [disappearance time and reappearance time of forepaw righting reflex(FRR),time of activity complete recovery] of 2-fold ED50 propofol with single intravenous injection were observed in alcohol dependence group,alcohol withdrawal group and control group,and corresponding time point and the frequency of respiration before administration were also observed. Changes of liver function indexes(serum albumin,alanine transaminase,total bilirubin,γ glutamyl transaminopeptidase)and liver histomorphology were observed 48 h after medication,10 in each group. RESULTS:ED50 of propofol in alcohol dependence model rats was 9.563 mg/kg,which was higher than 5.623 mg/kg of control group. ED50 of propofol in alcohol withdrawal model rats was 4.086 mg/kg,which was lower than 5.297 mg/kg of control group. Compared with control group,reappearance time of FRR was prolonged significantly in alcohol dependence group and alcohol withdrawal group (P＜0.05). There was no statistical significance in disappearance time of FRR or activity complete recovery time (P＞0.05). The frequency of respiration during FRR disappearance was lower than before propofol injection,FRR reappearance and activity complete recovery (P＜0.01). After intravenous injection of 2-fold ED50 propofol,reappearance time of FRR in alcohol dependence group and alcohol withdrawal group were longer than control group(P＜0.05)；the alcohol dependence group was longer than the alcohol withdrawal group(P＜0.05).The time of activity complete recovery in alcohol dependence group was longer than control group and alcohol withdrawal group (P＜0.05). The frequency of respiration in 3 groups during FRR disappearance were all lower than before propofol injection,FRR reappearance and activity complete recovery(P＜0.01). There was no significant difference in the change of liver function indexes or liver histomorphology. CONCLUSIONS:ED50 of propofol is increased in alcohol dependence rats,while ED50 of propofol is decreased in alcohol withdrawal rats. 2-fold ED50 of propofol has no significant toxicity to liver function.

Objective To analyze the negative experience from medical practice of medical students by Balint group case study,and to explore new approach for training doctor-patient communication skills.Methods 10 times of Balint group activities were held in Zhongshan Hospital of Fudan University,with one case each time.Grounded theory approach were applied for analyzing discussion record.Results The cases were occurred in doctor-patient interaction,teamwork,conflict between one's personal life and vocational development planning.Trigger events involved doctor-patient conflict,conflict of values,decision making problem while conffronted with incurable patients,role ambiguity,unfair treatment.Topics of discussion included emotional experience with patients,career development orientation,medical teamwork,clinical education of medical student.Conclusion Through practice of Balint group,medical students in teaching hospital can improve their awareness of complicating psycho-social problem of patients and themselves,as well as handling it.And it can improve the professional identity,professional growth and professional self-identity.

Objective To investigate nursing undergraduates' career maturity and its influencing factors.Methods A total of 467 nursing undergraduates from a certain comprehensive university were investigated with general informarion questionnaire,Undergraduate Career Maturity Inventory and Undergraduate Specialty Commitment.Results The mean score of career maturity was (3.12 ±0.29).The highest score and lowest score was (3.74 ± 0.45 ) for professional reference and (2.53 ± 0.61 ) for professional value,respectively.Nursing undergraduates' career maturity was influenced by grade,hometown,father' s education,participation and organization of social association activity,and specialty commitment ( P ＜ 0.05,P ＜ 0.01 ).Conclusions Career maturity of nursing undergraduates is generally well,but its overall level is rather low.Nursing undergraduates' career maturity is influenced by grade,hometown,father' s education,participation and organization of social association activity,and specialty commitment.