AIM: To further investagate the mechanism of thrombus formation and develop a new remedy of anti-thrombus formation. METHODS: The amplified DNA fragment of vWF-A1 domain was inserted into expression vector with 6?his taq (pQE-31), the recombinant expression vect or was transformed into E coli (strain M15) and induced by IPTG. The recombinant fragment, comprising residues 449-728 of mature vWF subunit, designate rvWF-A1. It was purified by Ni-NTA agarose column and renatured by Tris buffer containin g GSH and GSSG. FACS and platelet aggregometer were employed to analyse the rvWF -A1 function of binding to platelet glycoprotein Ib and inhibiting ristocetin-in duced platelet aggregation. RESULTS: The rvWF-A1 was expressed successfully in E coli, comin g up to 30% of total bacterial protein. Its purify was over 95% through Ni-NTA a garose. It was identified to have ability to bind to GPIb, its biologic activity to inhibit ristocetin-induced platelet aggregation was observed, and the inhibi tive rate was 84 7%. CONCLUSION: The above results indicated that high-level expressi on of rvWF-A1 was successfully achieved in E coli and rvWF-A1 may be an effectiv e antithromotic agent in preventing thrombus formation.

Objective To analyze the relationship between the catheter to vein ratio and the formation of peripheral insertion of central venous catheter (PICC) related upper extremity deep venous thrombosis (PICC-UEDVT) in cases having undergone PICC in patients at intensive care unit (ICU) and further identify the best optimal ratio cut-off point to reduce the incidence of PICC-UEDVT.Methods A retrospective study was conducted, including 69 patients having undergone PICC with complete clinical data admitted to the Department of Critical Care Medicine of the First Affiliated Hospital of Nanchang University from August 2013 to December 2016; their ages were > 18 years old and catheter indwelling times were > 1 week; the patients' basic information, disease related laboratory parameters and catheter insertion situation were collected. According to the occurrence of PICC-UEDVT, they were divided into PICC-UEDVT group and non PICC-UEDVT group; the receiver operating characteristic (ROC) curve of the catheter to vein ratio versus the incidence ofPICC-UEDVT was plotted to assess the optimal ratio to reduce the incidence of PICC-UEDVT.Results In the 69 patients, there were 7 patients in the PICC-UEDVT group and 62 patients in the non PICC-UEDVT group, the incidence of PICC-UEDVT being 10.14%. Four, 5 and 6 French (Fr) catheters were indwelled in 43, 23 and 3 cases respectively, and the range of catheter to vein ratio was 20% - 67%. The comparisons between PICC-UEDVT group and non PICC-UEDVT group in various aspects were as follows: the incidence of DVT in the PICC-UEDVT group was significantly higher than that in non PICC-UEDVT group [42.9% (3/7) vs. 6.5% (4/62)], the rate of using vasopressor drugs [57.14% (4/7) vs. 17.74% (11/62)], D-dimer level [mg/L: 9.0 (3.0, 12.3) vs. 1.8 (1.0, 3.6)], patients of indwelling 5Fr catheter [71.4% (5/7) vs. 29.0% (18/62)] and the percentage of patientsapplying catheter to vein ratio 45%-67% [57.14% (4/7) vs. 17.74% (11/62)] in PICC-UEDVT group were all higher than those in the non PICC-UEDVT group, the differences being statistically significant (allP < 0.05). ROC analysis showed that the catheter to vein ratio 44% was the optimal cut off or critical point, the area under the ROC curve (AUC) at that point was 0.755, 95% confidence interval (95%CI) = 0.554-0.955, sensitivity = 71.4% and specificity = 79.0%; compared with the patients using 45%-67% catheter to vein ratio, the incidence of PICC-UEDVT was 6.182 times higher than those using the ratio 20%-44% [odds ratio (OR) = 6.182, 95%CI = 1.208-31.634,P = 0.036]; however, there was no significant difference in incidence of PICC-UEDVT between 20%-32% and 33%-44% (P = 1.000).Conclusion It is found that the 44% catheter to vein ratio was the optimal critical point to reduce the incidence of PICC-UEDVT, possessing relatively high sensitivity and specificity; applying <44% catheter to vein ratio can decrease the risk of PICC-UEDVT occurrence in patients at ICU.

Objective The objective of this study was to investigate the underlying causes of catheter rupture in implantable venous assess ports among 4 paediatric patients and to summarise nursing experiences.Methods A total of 319 implantations of venous assess port were admitted in the Department of Paediatric Surgery of our hospital from March 2011 to January 2023,with an incidence rate of catheter fracture at 1.3%(4 cases).The ruptured catheters in all 4 paediatric patients were successfully retrieved via surgery.The reasons for catheter rupture as well as the methods for identification were analysed and summarised.Results In Case 1,a catheter rupture was located at 6 cm from the port and the ruptured catheter was not displaced.In Case 2,a linear crack was observed at 7 cm from the base of port without visible sign of catheter rupture,however,a leakage was observed from the crack when fluid was injected.In Case 3,the location of catheter rupture was identified at 11 cm from the port and again there was no evidence of displacement.However for Case 4,a catheter rupture occurred at just 1 cm away from the base of port,with a displacement along right atrium-right pulmonary artery-right inferior pulmonary artery.The causes of catheter rupture were attributed to frequent and prolonged neck and upper extremity activities in Cases 1,3 and 4,as well as an inappropriate handling of catheter in Case 2.After removal of the catheter,Cases 1,2 and 4 were kept in hospital for treatment of original illnesses,while Case 3 was discharged the day after the removal of catheter.Conclusion Catheter rupture is an extremely serious complication.It is imperative for healthcare personnel to adhere to standardised procedures and maintenance protocols,together with comprehensive health education to both parents and children.Early detection of an abnormality followed by prompt handling is crucial in ensuring the safety usage of an implantable venous assess port in paediatric patients.

miR-135 is a highly conserved miRNA in mammals and includes miR-135a and miR-135b.Recent studies have shown that miR-135b is a key regulatory factor in cardio-cerebrovascular diseases.It is involved in regulating the pathological process of myocardial infarction,myocardial ischemia/reperfusion injury,cardiac hypertrophy,atrial fibrillation,diabetic cardiomyopathy,atherosclerosis,pulmonary hyperten-sion,cerebral ischemia/reperfusion injury,Parkinson's disease,and Alzheimer's disease.Obviously,miR-135b is an emerging player in cardio-cerebrovascular diseases and is expected to be an important target for the treatment of cardio-cerebrovascular diseases.However,the crucial role of miR-135b in cardio-cerebrovascular diseases and its underlying mechanism of action has not been reviewed.Therefore,in this review,we aimed to comprehensively summarize the role of miR-135b and the signaling pathway mediated by miR-135b in cardio-cerebrovascular diseases.Drugs targeting miR-135b for the treatment of diseases and related patents,highlighting the importance of this target and its utility as a therapeutic target for cardio-cerebrovascular diseases,have been discussed.

【Objective】 To investigate the clinical characteristics and diagnosis and treatment of passenger lymphocyte syndrome (PLS) in patients following allogeneic hematopoietic stem cell transplantation (allo-HSCT). 【Methods】 A total of 489 patients who underwent allo-HSCT in Suzhou Hongci Hematology Hospital were retrospectively enrolled. The clinical process, diagnosis and treatment measures and prognosis of four patients complicated with PLS after transplantation were analyzed. 【Results】 Among the 489 patients, 4 were diagnosed with PLS. The blood types of donor/recipient ABO were all secondary incompatible (The blood type of donors were O and the recipients were A or B). The overall incidence of PLS in allo-HSCT was 0.82%(4/489)and 2.2%(4/179)in transplants with donor/recipient secondary incompatible ABO-blood types. PLS occured in 6-13 days after donor stem cell infusion. Clinical manifestations were dizziness and fatigue, low back pain, jaundice, deepening urine, rapid decrease in hemoglobin on laboratory tests, elevated indirect bilirubin and lactate dehydrogenase, positive urobilinogen, positive direct anti-human globulin test (DAT), and anti-A or anti-B antibodies against recipient red blood cells were detected in plasma. After the treatment of O-type washed red blood cells, methylprednisolone, gamma globulin, rituximab and other treatments, the hemolysis was improved. All patients achieved engraftment of neutrophil and platelet. Red blood cell transfusion was halted in 3 weeks. 【Conclusion】 PLS is a rare complication of allo-HSCT, which mainly occurs in allo-HSCT patients with secondary incompatibility of ABO blood group of donor/recipient. The clinical prognosis is good after properly treatment.

Objective To investigate the antimicrobial resistance profile of the clinical isolates collected from selected hospitals across China. Methods Twenty-nine general hospitals and five children's hospitals were involved in this program. Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems. Results were interpreted according to CLSI 2017 breakpoints. Results A total of 190 610 clinical isolates were collected from January to December 2017, of which gram negative organisms accounted for 70.8％ (134 951/190 610) and gram positive cocci 29.2％ (55 649/190 610). The prevalence of methicillin-resistant strains was 35.3％ in S. aureus (MRSA) and 80.3％ in coagulase negative Staphylococcus (MRCNS) on average. MR strains showed much higher resistance rates to most of the other antimicrobial agents than MS strains. However, 91.6％ of MRSA strains were still susceptible to trimethoprim-sulfamethoxazole, while 86.2％ of MRCNS strains were susceptible to rifampin. No staphylococcal strains were found resistant to vancomycin. E. faecalis strains showed much lower resistance rates to most of the drugs tested (except chloramphenicol) than E. faecium. Vancomycin-resistant Enterococcus (VRE) was identified in both E. faecalis and E. faecium. The identified VRE strains were mainly vanA, vanB or vanM type based on phenotype or genotype. The proportion of PSSP or PRSP strains in the non-meningitis S.pneumoniae strains isolated from children decreased but the proportion of PISP strains increased when compared to the data of 2016. Enterobacteriaceae strains were still highly susceptible to carbapenems. Overall, less than 10％ of these strains (excluding Klebsiella spp.) were resistant to carbapenems. The prevalence of imipenem-resistant K. pneumoniae increased from 3.0％ in 2005 to 20.9％ in 2017, and meropenem-resistant K. pneumoniae increased from 2.9％ in 2005 to 24.0％ in 2017, more than 8-fold increase. About 66.7％ and 69.3％ of Acinetobacter (A. baumannii accounts for 91.5％) strains were resistant to imipenem and meropenem, respectively. Compared with the data of year 2016, P. aeruginosa strains showed decreasing resistance rate to carbapenems. Conclusions Bacterial resistance is still on the rise. It is necessary to strengthen hospital infection control and stewardship of antimicrobial agents. The communication between laboratorians and clinicians should be further improved in addition to surveillance of bacterial resistance.

Objective To investigate the distribution and antimicrobial resistance profiles of the common pathogens isolated from urine from 2015 to 2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods The bacterial strains were isolated from urine and identified routinely in 51 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Antimicrobial susceptibility was determined by Kirby-Bauer method,automatic microbiological analysis system and E-test according to the unified protocol.Results A total of 261 893 nonduplicate strains were isolated from urine specimen from 2015 to 2021,of which gram-positive bacteria accounted for 23.8％(62 219/261 893),and gram-negative bacteria 76.2％(199 674/261 893).The most common species were E.coli(46.7％),E.faecium(10.4％),K.pneumoniae(9.8％),E.faecalis(8.7％),P.mirabilis(3.5％),P.aeruginosa(3.4％),SS.agalactiae(2.6％),and E.cloacae(2.1％).The strains were more frequently isolated from inpatients versus outpatients and emergency patients,from females versus males,and from adults versus children.The prevalence of ESBLs-producing strains in E.coli,K.pneumoniae and P.mirabilis was 53.2％,52.8％and 37.0％,respectively.The prevalence of carbapenem-resistant strains in E.coli,K.pneumoniae,P.aeruginosa and A.baumannii was 1.7％,18.5％,16.4％,and 40.3％,respectively.Lower than 10％of the E.faecalis isolates were resistant to ampicillin,nitrofurantoin,linezolid,vancomycin,teicoplanin and fosfomycin.More than 90％of the E.faecium isolates were ressitant to ampicillin,levofloxacin and erythromycin.The percentage of strains resistant to vancomycin,linezolid or teicoplanin was＜2％.The E.coli,K.pneumoniae,P.aeruginosa and A.baumannii strains isolated from ICU inpatients showed significantly higher resistance rates than the corresponding strains isolated from outpatients and non-ICU inpatients.Conclusions E.coli,Enterococcus and K.pneumoniae are the most common pathogens in urinary tract infection.The bacterial species and antimicrobial resistance of urinary isolates vary with different populations.More attention should be paid to antimicrobial resistance surveillance and reduce the irrational use of antimicrobial agents.

Objective To understand the distribution and changing resistance profiles of clinical isolates of Enterococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Enterococcus according to the unified protocol of CHINET program by automated systems,Kirby-Bauer method,or E-test strip.The results were interpreted according to the Clinical & Laboratory Standards Institute(CLSI)breakpoints in 2021.WHONET 5.6 software was used for statistical analysis.Results A total of 124 565 strains of Enterococcus were isolated during the 7-year period,mainly including Enterococcus faecalis(50.7％)and Enterococcus faecalis(41.5％).The strains were mainly isolated from urinary tract specimens(46.9％±2.6％),and primarily from the patients in the department of internal medicine,surgery and ICU.E.faecium and E.faecalis strains showed low level resistance rate to vancomycin,teicoplanin and linezolid(≤3.6％).The prevalence of vancomycin-resistant E.faecalis and E.faecium was 0.1％and 1.3％,respectively.The prevalence of linezolid-resistant E.faecalis increased from 0.7％in 2015 to 3.4％in 2021,while the prevalence of linezolid-resistant E.faecium was 0.3％.Conclusions The clinical isolates of Enterococcus were still highly susceptible to vancomycin,teicoplanin,and linezolid,evidenced by a low resistance rate.However,the prevalence of linezolid-resistant E.faecalis was increasing during the 7-year period.It is necessary to strengthen antimicrobial resistance surveillance to effectively identify the emergence of antibiotic-resistant bacteria and curb the spread of resistant pathogens.

Objective To examine the changing antimicrobial resistance profile of Enterobacter spp.isolates in 53 hospitals across China from 2015 t0 2021.Methods The clinical isolates of Enterobacter spp.were collected from 53 hospitals across China during 2015-2021 and tested for antimicrobial susceptibility using Kirby-Bauer method or automated testing systems according to the CHINET unified protocol.The results were interpreted according to the breakpoints issued by the Clinical & Laboratory Standards Institute(CLSI)in 2021(M100 31st edition)and analyzed with WHONET 5.6 software.Results A total of 37 966 Enterobacter strains were isolated from 2015 to 2021.The proportion of Enterobacter isolates among all clinical isolates showed a fluctuating trend over the 7-year period,overall 2.5％in all clinical isolates amd 5.7％in Enterobacterale strains.The most frequently isolated Enterobacter species was Enterobacter cloacae,accounting for 93.7％(35 571/37 966).The strains were mainly isolated from respiratory specimens(44.4±4.6)％,followed by secretions/pus(16.4±2.3)％and urine(16.0±0.9)％.The strains from respiratory samples decreased slightly,while those from sterile body fluids increased over the 7-year period.The Enterobacter strains were mainly isolated from inpatients(92.9％),and only(7.1±0.8)％of the strains were isolated from outpatients and emergency patients.The patients in surgical wards contributed the highest number of isolates(24.4±2.9)％compared to the inpatients in any other departement.Overall,≤ 7.9％of the E.cloacae strains were resistant to amikacin,tigecycline,polymyxin B,imipenem or meropenem,while ≤5.6％of the Enterobacter asburiae strains were resistant to these antimicrobial agents.E.asburiae showed higher resistance rate to polymyxin B than E.cloacae(19.7％vs 3.9％).Overall,≤8.1％of the Enterobacter gergoviae strains were resistant to tigecycline,amikacin,meropenem,or imipenem,while 10.5％of these strains were resistant to polycolistin B.The overall prevalence of carbapenem-resistant Enterobacter was 10.0％over the 7-year period,but showing an upward trend.The resistance profiles of Enterobacter isolates varied with the department from which they were isolated and whether the patient is an adult or a child.The prevalence of carbapenem-resistant E.cloacae was the highest in the E.cloacae isolates from ICU patients.Conclusions The results of the CHINET Antimicrobial Resistance Surveillance Program indicate that the proportion of Enterobacter strains in all clinical isolates fluctuates slightly over the 7-year period from 2015 to 2021.The Enterobacter strains showed increasing resistance to multiple antimicrobial drugs,especially carbapenems over the 7-year period.

Objective To understand the changing distribution and antimicrobial resistance profiles of Proteus,Morganella and Providencia in hospitals across China from January 1,2015 to December 31,2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods Antimicrobial susceptibility testing was carried out following the unified CHINET protocol.The results were interpreted in accordance with the breakpoints in the 2021 Clinical & Laboratory Standards Institute(CLSI)M100(31 st Edition).Results A total of 32 433 Enterobacterales strains were isolated during the 7-year period,including 24 160 strains of Proteus,6 704 strains of Morganella,and 1 569 strains of Providencia.The overall number of these Enterobacterales isolates increased significantly over the 7-year period.The top 3 specimen source of these strains were urine,lower respiratory tract specimens,and wound secretions.Proteus,Morganella,and Providencia isolates showed lower resistance rates to amikacin,meropenem,cefoxitin,cefepime,cefoperazone-sulbactam,and piperacillin-tazobactam.For most of the antibiotics tested,less than 10％of the Proteus and Morganella strains were resistant,while less than 20％of the Providencia strains were resistant.The prevalence of carbapenem-resistant Enterobacterales(CRE)was 1.4％in Proteus isolates,1.9％in Morganella isolates,and 15.6％in Providencia isolates.Conclusions The overall number of clinical isolates of Proteus,Morganella and Providencia increased significantly in the 7-year period from 2015 to 2021.The prevalence of CRE strains also increased.More attention should be paid to antimicrobial resistance surveillance and rational antibiotic use so as to prevent the emergence and increase of antimicrobial resistance.