This study established an efficient and specific method for type analysis of genetic variants of Balantioides coli.The restriction endonucleases ApoI and PflMI were selected to digest the PCR amplification products of ITS1-5.8S rDNA-ITS2 of B.coli,and to establish a PCR-RFLP typing method.The PCR-RFLP method was subsequently used to analyze the genetic variants in clinical fecal samples from pigs,sheep,and guinea pigs.The PCR-RFLP method based on ApoI and PflMI accurately distinguished the main A and B genetic variants of B.coli,and further divided the main B type into B-c and B-t sub-types of genetic variants with PflMI.Compared with the results of microscopy and sequencing,the PCR-RFLP method showed good specificity and higher sensitivity,and was able to identify not only single but also multiple variants of B.coli in a single clinical sample.This study successfully established the PCR-RFLP method for B.coli,which can be used for genetic di-versity identification and molecular epidemiological studies of B.coli.

Objective:To observe the genetic variation of SH2B3 in patients with myeloid neoplasms.Methods:The results of targeted DNA sequencing associated with myeloid neoplasms in the Department of Hematology,Xuanwu Hospital,Capital Medical University from November 2017 to November 2022 were retrospectively analyzed,and the patients with SH2B3 gene mutations were identified.The demographic and clinical data of these patients were collected,and characteristics of SH2B3 gene mutation,co-mutated genes and their correlations with diseases were analyzed.Results:The sequencing results were obtained from 1 005 patients,in which 19 patients were detected with SH2B3 gene mutation,including 18 missense mutations(94.74％),1 nonsense mutation(5.26％),and 10 patients with co-mutated genes(52.63％).Variant allele frequency(VAF)ranged from 0.03 to 0.66.The highest frequency mutation was p.Ile568Thr(5/19,26.32％),with an average VAF of 0.49,involving 1 case of MDS/MPN-RS(with SF3B1 mutation),1 case of MDS-U(with SF3B1 mutation),1 case of aplastic anemia with PNH clone(with PIGA and KMT2A mutations),2 cases of MDS-MLD(1 case with SETBP1 mutation).The other mutations included p.Ala567Thr in 2 cases(10.53％),p.Arg566Trp,p.Glu533Lys,p.Met437Arg,p.Arg425Cys,p.Glu314Lys,p.Arg308*,p.Gln294Glu,p.Arg282Gln,p.Arg175Gln,p.Gly86Cys,p.His55Asn and p.Gln54Pro in 1 case each.Conclusion:A wide distribution of genetic mutation sites and low recurrence of SH2B3 is observed in myeloid neoplasms,among of them,p.Ile568Thr mutation is detected with a higher incidence and often coexists with characteristic mutations of other diseases.

Objective:To investigate the spectrum and antimicrobial resistance of major pathogens causing nosocomial infections in China during 2020-2021.Methods:A total of 1 311 non-duplicated nosocomial pathogens causing bloodstream infections (BSI, n=670), hospital-acquired pneumonia (HAP, n=394) and intra-abdominal infections (IAI, n=297) were collected from 10 teaching hospitals across China. The minimum inhibitory concentrations (MICs) of clinical common strains were determined using agar dilution or broth microdilution method. Interpretation of reults followed the CLSI M100-Ed33 criteria, with data analysis conducted using WHONET-5.6 software. The Chi-square test was used to compare rates. Results:The most prevalent pathogens causing BSI were Escherichia coli (21.2%, 142/670), Klebsiella pneumoniae (14.9%, 100/670) and Staphylococcus aureus (11.5%, 77/670); the most prevalent pathogens causing HAP were K. pneumoniae (27.7%, 109/394), Acinetobacter baumanii (22.1%, 87/394) and Pseudomonas aeruginosa (18.3%, 72/394). IN IAI, E. coli (24.3%, 60/247), Enterococcus faecium and K. pneumoniae (both 14.6%, 36/247) were dominated. All S. aureus strains were susceptible to tigecycline, linezolid, daptomycin and glycopeptides. Rates of methicillin-resistant S. aureus (MRSA) and coagulase-negative Staphylococcus (MRCNS) were 36.5% (42/115) and 74.5% (38/51), respectively. The rate of vancomycin-resistant E. faecium and E. faecalis was 3.3% (3/90) and 1.9% (1/53), respectively. The prevalence of extended-spectrum β-lactamase (ESBL) was 23.7% (58/245) in K. pneumonia and 60.5% (130/215) in E. coli.The rate of carbapenem-resistant K. pneumonia and E. coli was 29.8% (73/245) and 4.2% (9/215), respectively; the percentage of tigecycline-resistant K. pneumonia and E. coli was 1.6% (4/245) and 0, respectively; the rate of colistin-resistant K. pneumonia and E. coli was 1.6% (4/245) and 2.8% (6/215), respectively; the percentage of ceftazidime/avibactam-resistant K. pneumonia and E. coli was 2.0% (5/245) and 2.3% (5/215), respectively. The rate of carbapenem-resistant A. baumanii and P. aeruginosa was 76.7% (125/163) and 28.4% (33/116), respectively. A. baumanii showed low susceptibility to most antimicrobial agents except colistin (98.8%, 161/163) and tigecycline (89.6%, 146/163). Colistin, amikacin and ceftazidime/avibactam demonstrated high antibacterial activity against P. aeruginosa with susceptility rates of 99.1% (115/116), 94.0% (109/116) and 83.6% (97/116), respectively. Conclusions:The major pathogens of nosocomial infections were K. pneumonia, E. coli, A. baumanii, P. aeruginosa and S. aureus. Nosocomial Gram-negative pathogens exhibited high susceptibilities to tigecycline, colistin and ceftazidime/avibactam. Antimicrobial resistance in A. baumannii remains a significant challenge. The increasing prevalence of carbapenem-resistant Enterobacterales underscores the urgency of antibiotics rational applications and hospital infection controls.

Objective To design a novel oxygenator to solve the existing problems of extracorporeal membrane oxygenation(ECMO)machine in high transmembrane pressure difference,low efficiency of blood oxygen exchange and susceptibility to thrombosis.Methods The main body of the oxygenator vascular access flow field was gifted with a flat cylindrical shape.The topology of the vascular access was modeled in three dimensions,and the whole flow field was cut into a blood inlet section,an inlet buffer,a heat exchange zone,a blood oxygen exchange zone,an outlet buffer and a blood outlet section.The oxygenator was compared with Quadrox oxygenator by means of ANSYS FLUENT-based simulation and prototype experiments.Results Simulation calculations showed the oxygenator designed was comparable to the clinically used ones in general,and gained advantages in transmembrane pressure difference,blood oxygen exchange and flow uniformity.Experimental results indicated that the oxygenator behaved better than Quadrox oxygenator in transmembrane pressure difference and blood oxygen exchange.Conclusion The oxygenator has advantages in transmem-brane pressure difference,temperature change,blood oxygen ex-change and low probability of thrombosis.[Chinese Medical Equipment Journal,2024,45(3):23-28]

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Hip fracture in the elderly is characterized by high incidence, high disability rate, and high mortality and has been recognized as a public health issue threatening their health. Surgery is the preferred choice for the treatment of elderly patients with hip fracture. However, lower extremity deep venous thrombosis (DVT) has an extremely high incidence rate during the perioperative period, and may significantly increase the risk of patients′ death once it progresses to pulmonary embolism. In response to this issue, the clinical guidelines and expert consensuses all emphasize active application of comprehensive preventive measures, including basic prevention, physical prevention, and pharmacological prevention. In this prevention system, basic prevention is the basis of physical and pharmacological prevention. However,there is a lack of unified and definite recommendations for basic preventive measures in clinical practice. To this end, the Orthopedic Nursing Professional Committee of the Chinese Nursing Association and Nursing Department of the Orthopedic Branch of the China International Exchange and Promotive Association for Medical and Health Care organized relevant nursing experts to formulate Expert consensus on perioperative basic prevention for lower extremity deep venous thrombosis in elderly patients with hip fracture ( version 2024) . A total of 10 recommendations were proposed, aiming to standardize the basic preventive measures for lower extremity DVT in elderly patients with hip fractures during the perioperative period and promote their subsequent rehabilitation.