0.05),respectively.Conclusion:Gatifloxacin injection is a highly effective and well tolerated antibacterial agent for the treatment of moderate and severe bacterial infections.

Objective:To identify the sequence of the multiple-antibiotic-resistant efflux acrAB gene in Salmonella typhi 275(a clinically isolated strain) and analyze its structure,amino acid sequence.Methods:The whole acrAB gene of Salmonella typhi 275 were amplified by PCR with the primers designed from Genebank,and the sequence of products and the amino acid sequence were detected.Results:The whole sequence of acrAB gene of Salmonella typhi 275 contained 5156 bases and 99.38% identity were found in comparison with the reference sequence of Salmonella typhi (Genebank No. AL627267);84.69% identity were detected in comparison with that of Escherichia coli (Genebank No.ECUO0734).The acrR,actA,acrB of Salmonella typhi 275 coded AcrR,AcrA,AcrB proteins with 217,397 and 1049 amino acids,respectively.1 amino acid alteration existed in both AcrA (Ser270Thr)and AcrB (Met964Thr) in comparison with the reference Genebank amino acids sequence.Compared with Escherichia coli,28,33 and 56 amino acids alteration and 86.98%,91.69% and 94.66% identity in the AcrR,Acta and AcrB were found respectively.2 additional amino acids existed in AcrR of Salmonella typhi 275.The promoter region of Acta and acrR was located in 4367-4507 bases and the SD sequence was in 4373-4377 bases.Conclusion:The multiple-antibiotic-resistant active efflux system gene acrAB of Salmonella typhi shows high homology in bases,amino acids and protein structure with that of Escherichia coli and it is the possible reason that Salmonella typhi is resistant to multi-antibiotics without similar chemical structure.

Objective To investigate the effects of low density lipoprotein receptor (LDLr) pathway on podocyte injury in diabetic nephropathy (DN) under inflammatory stress.Methods Male db/db mice and db/m mice were randomly divided into four groups (8 mice in each group):db/m group (control),casein injected db/m group (db/m + casein),db/db group (db/db),and casein injected db/db group (db/db + casein).An inflamed model of DN was established according to our previous study.24-hour urinary protein was measured every week.The plasma lipid profile was detected by clinical biochemistry assay.Podocyte changes were evaluated by electron microscope and immunofluorescent staining.Lipid accumulation in the kidney was evaluated by oil red O staining and intracellular cholesterol quantitative assay.The protein expression of Wilm's tumor-1 (WT-1),nephrin,α-smooth muscle actin (t-SMA),and molecules correlated with LDLr pathway were examined by immunohistochemical staining or Western blotting.The colocalized protein expression of LDLr with WT-1 was examined by immunofluorescent staining and laser confocal microscopy.Results There were no differences in plasma levels of LDL and HDL among four groups.Compared with db/db group,the db/db+ casein group showed markedly increased 24-hour urinary protein,more significant podocyte foot process effacement and podocyte damage,increased lipid droplet accumulation in kidneys,increased protein expressions of LDLr,SCAP and SREBP-2 in kidneys (all P ＜ 0.05).Interestingly,increased LDLr protein expression in kidneys of db/db mice was negatively correlated with decreased nephrin protein expression (r =-0.855,P ＜ 0.01) and positively correlated with increased α-SMA protein expression (r=0.768,P ＜ 0.01).Conclusions The disruption of LDLr pathway induced by inflammation contributes to podocyte injuries in diabetic nephropathy.

ObjectiveTo systematically evaluate the association between vitamin D level and nonalcoholic fatty liver disease (NAFLD) in children and adolescents. MethodsRelated English and Chinese databases, including PubMed, Cochrane Library, Embase, CNKI, CBM, Wanfang Data, and VIP, were searched for studies on the association between vitamin D level and NAFLD in children and adolescents published up to August 2020. Newcastle-Ottawa Scale (NOS) was used to evaluate quality of studies, and RevMan 5.3 software was used for data analysis. ResultsA total of 10 articles were included in the meta-analysis, with 622 patients in the NAFLD group and 1608 in the healthy control group. All 10 articles had an NOS score of ≥6. A pooled analysis of the 10 articles was performed using a random effects model (I2=97%, P＜0.05). The NAFLD group had a significantly lower serum 25(OH) D level than the healthy control group (standardized mean difference=-1.40, 95% confidence interval: -2.07 to -0.72). ConclusionThere is a significant reduction in serum vitamin D level in children and adolescents with NAFLD, which may be associated with the progression and severity of NAFLD.

The department of Blood Transfusion in the First Affiliated Hospital of Chongqing Med-ical University has started clinical practice teaching reform and established blood transfusion medical in-terns since 2013. Combined with teaching practice, this study proposed 8 points of teaching experience:providing detailed training rules and assessment criteria; facilitating the close integration between standard-ized technical operationsand clinical practice; promoting flexible communication for a harmonious doctor-patient relationship; adopting question-oriented teaching to mobilize students' enthusiasm; intensifying biosecurity training to ensure blood and personal safety; developing a sense of responsibility; learning bloodtransfusion techniques and blood management knowledge for the pursuit of safe blood transfusion; cultivating strong innovation ability to improve the level of scientific research. For cultivating high-quality talents of blood transfusion, we should update teaching philosophy, adjust teaching methods to explore tailored teach-ing for blood transfusion interns.

Myasthenia gravis(MG)is an autoimmune disease mainly mediated by autoantibodies that disorders the transmission of excitation at the neuromuscular junction.The predominant clinical manifestation is the muscle fluctuant weakness and fatigability,and the extraocular and skeletal muscles are slightly affected at the early onset for the majority of MG patients.However,there is a rapid progression in a short period of time for a small group,involving the laryngeal mus-cles and respiratory muscles and developing the myasthenia crisis,which severely threatens their lives.It's commonly used for such patients to be rescued by therapeutic plasma exchange(TPE)or intravenous immunoglobulins(IVIG)that rapidly relieves their symptoms of muscle weakness and improves the respiratory function.In recent years,plentiful clinical studies about TPE have emerged,and the clinical value of TPE in improving MG symptoms,exerting early efficacy,reducing the length of ICU hospital stay and its safety has been gradually clarified.This review aims to summarize the clinical research ad-vancement of TPE in the treatment of MG in terms of basic conditions of MG and TPE,the therapeutic efficiency and safety of TPE,and the application of TPE extension technology in the treatment of MG by searching for clinical research articles at home and abroad in the past 5 years,which can provide reference for better clinical application of MG.

To cultivate high-quality professionals of transfusion medicine and construct a new mode of undergraduate practice of transfusion medicine. Since 2013, orientation interns in blood transfusion medicine were recruited from the undergraduate program of laboratory medicine, and a new teaching mode of orientation practice of blood transfusion medicine was established from the aspects of teaching staff, rotation of posts, practice content and comprehensive quality. Through the new training mode of orientation practice, excellent transfusion medical professionals with solid basic knowledge, strong operational skills and high comprehensive quality were cultivated. The establishment of the oriented practice mode of blood transfusion medicine is beneficial to the cultivation and output of high-quality transfusion talents and plays a positive role in promoting the development of transfusion medicine education.

【Objective】 To compare the efficacy and safety of transfusion of suspended RBCs and washed RBCs in patients with positive direct Coombs testing results. 【Methods】 A retrospective analysis was conducted on 98 patients with positive direct Coombs testing results as 2+ or less in the First Affiliated Hospital of Chongqing Medical University from January 2015 to December 2020. Among them, 31 patients, from January 2015 to December 2016, were transfused with washed RBCs and set as the control group; the other 67 patients, from January 2017 to December 2020, transfused with suspended RBCs, were enrolled as the experimental group. The changes of main laboratory indexes and the incidence of transfusion adverse reactions before and after transfusion of 2 U and 4 U RBCs were compared between the two groups to evaluate the efficacy and safety of transfusion. 【Results】 After 2 U and 4 U transfusion, Hb increased by 12±4.967 (g/L) and 23.78±12.736 (g/L) in the control group, while 12.85±7.109 (g/L) and 22.68±9.832 (g/L) in the experimental group, All transfusions of the two groups were effective, and no significant differences in Hb, TBIL, IBIL and LDH were noticed by groups (P>0.05). No significant difference in the incidence of adverse reactions to blood transfusion between the 2 groups was observed (P>0.05). 【Conclusion】 The transfusion of suspended RBCs is safe and effective in patients with positive direct Coombs testing results as 2+ or less, and the transfusion of washed RBCs was unnecessary.

【Objective】 To explore platelet antibody production and its influencing factors in common platelet transfusion diseases. 【Methods】 From January 2018 to June 2020, patients who applied for platelet transfusion in the First Affiliated Hospital of Chongqing Medical University were enrolled. The solid phase agglutination method was used to detect the platelet antibodies of the patients. The platelet antibody positive rate of common platelet transfusion diseases and the types of diseases with higher platelet antibody-positive rates were analyzed. 【Results】 The overall positive rate of platelet antibodies in transfusion candidates was 15.0%. The 21~40 years old age patients(21.5%), females(18%) had a significantly higher platelet antibody positive rate than other ages and males(12.1%) (P<0.05). Besides, patients with a history of blood transfusion and pregnancy also had a higher platelet antibody positive rate. Tumors, blood and hematopoietic organ diseases, and digestive system diseases have higher platelet antibody-positive rates, which were 24.0%, 18.3%, and 16.6%, respectively. The platelet antibody positive rate varies significantly in common platelet transfusion diseases. As to transfused patients stratified by diseases, the platelet antibody positive rate of myeloid leukemia(48.7%)was higher than that of other diseases(P<0.05). In comparison, the platelet antibody positive rate of non-transfusion patients with liver failure and miscellaneous diseases(46.7%)was higher than that of others (P<0.05). 【Conclusion】 The positive rate of platelet antibody is somewhat higher in female, 21~40 years old patients. History of blood transfusion is a key risk factor for the production of platelet antibodies.

【Objective】 To analyze the root causes of adverse events to insufficient plasma transfusion, so as to explore improvement measures, optimize the transfusion strategy and avoid such adverse events. 【Methods】 The root causes of insufficient plasma transfusion were analyzed by health care failure mode and effect analysis, the targeted improvement measures were formulated and the effect was evaluated. 【Results】 After the improvement, the incidence of adverse events to insufficient plasma transfusion decreased significantly.The risk priority value affecting the safety of blood transfusion decreased from 70 to 8, and the proportion of coagulation function test after blood transfusion increased from 44.61%(1 309/2 934)in 2012 to 80.55% (2 187/2 715)in 2019, and plasma transfusion volume per capital increased from 300 mL to 528 mL. PT and APTT values after plasma transfusion in 2019 significantly increased compared with those in 2012. Meanwhile, the proportion of plasma transfusion in hospitalized patients decreased from 3.16% (2 934/92 838)to 2.12%(2 715/128 352). 【Conclusion】 Risk management of quality and safety of blood transfusion by combing healthcare failure mode, effect analysis and root cause analysis(RCA) can improve the risk awareness of clinical blood transfusion, optimize the proportion of plasma transfusion, and is essential to ensure the safety and effectiveness of blood transfusion and improve the prognosis of transfused patients.