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 investigate the molecular mechanism and distribution characteristics of RhD negative phenotypes in Han population of blood donors in Wuhu city.Methods:A total of 210 RhD-samples from August 2021 to August 2022 were screened by serological test and collected from Wuhu Central Blood Station for the voluntary blood donor population.Exons 1 and 10 of the RHD gene were amplificated by PCR to determine whether the samples had the RHD gene.Exons 1-10 of the RHD gene were amplificated by PCR and zygosity analysis were performed in 82 samples containing D gene,and Sanger sequencing was performed on 55 samples containing all RHD exons to determine the genotype.Results:Among 210 RhD-specimens,128 cases(60.38％)had RHD gene deletion.27 cases had partial exons of RHD,including 2 cases with RHD*DVI.3/RHD*01N.01,24 cases with RHD*01N.04/RHD*01N.01,and 1 case with RHD-CE(2-10)/RHD*01N.01.55 cases had retained all of 10 exons,including 4 cases with RHD*01/RHD*01N.01,6 cases with RHD*15/RHD*01N.01,1 case with RHD*01W.72/RHD*01N.01,1 case with RHD*15/RHD*01EL.01,39 cases with RHD*01EL.01/RHD*01N.01,and the remaining 4 cases were determined to have no RHD gene deletion by zygosity analysis and sequencing showed the presence of 1227G＞A mutation loci.Conclusion:There is polymorphism in the molecular mechanism of RhD-D gene in Wuhu blood donor population,among which RHD*01EL.01 and RHD*15 are the main variants in this region.The results of this study provide a theoretical basis for RhD blood group identification and clinical blood transfusion in this region.

Human parvovirus B19 (HPVB19) belongs to Parvoviridae, a genus of erythrovirus, and has been associated with various human diseases, and HPVB19 infection is one of the most important causes of refractory anemia after allogeneic hematopoietic stem cell transplantation (allo-HSCT). This study retrospectively analyzed 24 patients with HSCT combined with HPVB19 infection to collate and summarize the clinical presentation, treatment, and regression of patients with combined HPVB19 infection after allo-HSCT and provide experience in the management of HPVB19 infection after allo-HSCT. The median age of the patients with HPVB19 infection was 25 years, and the median time of infection occurrence was +107 days after transplantation, and 22 (91.7% ) had anemia with a median hemoglobin (HGB) level of 77.5 (46-149) g/L, and 13 (54.2% ) had new-onset anemia or persistent decline in HGB. The median length of hospital stay was 19 days. Among patients with new-onset anemia or persistent decline in HGB, the mean increase in HGB after treatment with intravenous immunoglobulin and/or antiviral therapy was 15.69 g/L, and treatment was effective in 10 (76.92% ) patients. HPVB19 infection should be alerted to the development of refractory anemia after HSCT; despite the lack of specific treatment, the overall prognosis of HPVB19-infected patients is good.

Objective:To evaluate the safety of patients with hepatic adenoma undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) .Methods:A retrospective analysis of the clinical characteristics and prognosis of eight patients with hepatic adenoma who underwent allo-HSCT in the Hematology Department of Peking University People’s Hospital from January 2010 to March 2024 was conducted.Results:Of the eight patients who underwent allo-HSCT with hepatic adenoma, one patient was considered MDS-h transfusion-dependent and seven had aplastic anemia. The median age of the patients was 23 years (13-48 years). The median time from the diagnosis of AA or MDS to transplantation was 14 years (6-24 years), whereas the median time from taking androgens to diagnosing hepatic adenoma was 9 years (5-13 years). Six cases underwent haplo-HSCT, one case underwent matched unrelated donor HSCT, and one case underwent matched related donor HSCT. All patients achieved neutrophil engraftment at a median time of 11.5 days (11-20 days) and PLT engraftment within 60 days at a median of 19 days (10-37 days) after haplo-HSCT. Moreover, seven patients developed CMV anemia after transplantation, three patients had hemorrhagic cystitis, and two patients developed acute GVHD. During and after transplantation, eight patients did not show severe liver function damage or rupture of hepatic adenoma. In relation to imaging size, four patients showed varying degrees of reduction in hepatic adenoma size after transplantation, whereas four patients did not show significant changes in hepatic adenoma size after transplantation. The median follow-up time was 540.5 (30-2 989) days. Of the eight patients, six survived and two died. Furthermore, no direct correlation was observed between death and hepatic adenoma.Conclusion:Patients with hepatic adenomas undergoing allo-HSCT are not contraindications for transplantation, which will not increase transplant-related mortality.

This study included 20 patients with hematological diseases who developed Pneumocystis jirovecii pneumonia (PJP) after receiving allogeneic hematopoietic stem cell transplantation (allo-HSCT) from April 2014 to October 2022 at Peking University People’s Hospital. The 20 patients comprised 13 males (65.0% ) and seven females (35.0% ), with a median age of 34 (19-60) years. Eleven cases (55.0% ) of acute myeloid leukemia, four cases (20.0% ) of acute lymphocytic leukemia, two cases (10.0% ) of myelodysplastic syndrome, one case (5.0% ) of chronic myelomonocytic leukemia, one case (5.0% ) of non-Hodgkin lymphoma, and one case (5.0% ) of aplastic anemia were analyzed. Three cases (15.0% ) of HLA-identical sibling hematopoietic stem cell transplantation, three cases (15.0% ) of matched unrelated donor hematopoietic stem cell transplantation, and 14 cases (70.0% ) of haploid hematopoietic stem cell transplantation were identified. The median onset time of PJP was 353 (74-1121) days after transplantation. The clinical symptoms mainly included fever, cough, expectoration, and dyspnea. All patients presented signs of infection based on the CT scan, including bilateral diffuse ground-glass opacities, patchy shadows, and solid nodules. Nine patients (45.0% ) required respiratory support via nasal catheter oxygen inhalation, while seven patients (35.0% ) required ventilator-assisted breathing. Seven (35.0% ) severe infections and 13 (65.0% ) mild to moderate infections were recorded. Moreover, eight patients (40.0% ) were complicated with human cytomegalovirus infection, whereas two patients were complicated with EB virus infection. Furthermore, all 20 patients received treatment with compound sulfamethoxazole (standard dose, 11 cases; low dose, 9 cases). Furthermore, 19 patients survived and one patient died.

AIM:This study employs Brainbow 2.1 mice to trace myocardial cell lineage and investigates the optimal dose of tamoxifen for labeling proliferating myocardial cells.METHODS:Four-week-old Brainbowfl/+;Myh6-Mer-CreMer+mice were administered tamoxifen at three different doses(3,9 and 27 mg/kg)via intraperitoneal injection to in-duce Cre recombinase expression and label myocardial cells with specific colors.Four weeks later,the samples were stained,and the number of myocardial cells labeled with varying doses of tamoxifen was quantified under confocal micro-scope.This quantification included the proportion of individually labeled cells,adjacent clusters of two cells,and clusters of three or more cells.An appropriate dose(9 mg/kg)of tamoxifen for labeling Brainbow mice was selected to compare myocardial cell proliferation between sham and myocardial infarction(MI)model groups.RESULTS:(1)After 9 mg/kg tamoxifen injection,the proportion of individually labeled cells was 99.13%±0.03%,that of adjacent 2-cell clusters was 0.82%±0.09%,and that of≥3-cell clusters was 0.05%±0.01%.The 3 mg/kg group had fewer total labeled cells,while the 27 mg/kg group showed significant clonal expansion and enrichment.(2)After labeling myocardial cells with 9 mg/kg tamoxifen,the MI mice showed increased proportions of 2-cell and≥3-cell clusters compared with sham group(P<0.01),indicating an increase in myocardial cell proliferation after MI.CONCLUSION:The proportion of adjacent myocardial cell clusters labeled with 9 mg/kg tamoxifen more closely approximates the physiological myocardial cell proliferation rate,indicating 9 mg/kg as the most suitable tamoxifen dose for tracing myocardial cell proliferation.

Objective To investigate how maternal MTR gene polymorphisms and their interactions with periconceptional folic acid supplementation are associated with the incidence of ventricular septal defects(VSD)in offspring.Methods A case-control study was conducted,recruiting 426 mothers of infants with VSD under one year old and 740 mothers of age-matched healthy infants.A questionnaire survey collected data on maternal exposures,and blood samples were analyzed for genetic polymorphisms.Multivariable logistic regression analysis and inverse probability of treatment weighting were used to analyze the associations between genetic loci and VSD.Crossover analysis and logistic regression were utilized to examine the additive and multiplicative interactions between the loci and folic acid intake.Results The CT and TT genotypes of the maternal MTR gene at rs6668344 increased the susceptibility of offspring to VSD(P<0.05).The GC and CC genotypes at rs3768139,AG and GG at rs1050993,AT and TT at rs4659743,GG at rs3768142,and GT and TT at rs3820571 were associated with a decreased risk of VSD(P<0.05).The variations at rs6668344 demonstrated an antagonistic multiplicative interaction with folic acid supplementation in relation to VSD(P<0.05).Conclusions Maternal MTR gene polymorphisms significantly correlate with the incidence of VSD in offspring.Mothers with variations at rs6668344 can decrease the susceptibility to VSD in their offspring by supplementing with folic acid during the periconceptional period,suggesting the importance of periconceptional folic acid supplementation in genetically at-risk populations to prevent VSD in offspring.

Objective:To compare and explore the diagnostic performance of adding value of transabdominal and transvaginal contrast-enhanced ultrasound (CEUS) to Ovarian-Adnexal Reporting and Data System (O-RADS US) risk stratification and management system in differential diagnosis of adnexal masses.Methods:A total of 180 adnexal masses with solid components in 175 women were enrolled retrospectively between September 2021 and November 2022. All patients underwent routine Doppler ultrasound examinations and CEUS examinations. Among these masses, 107 masses underwent with transabdominal CEUS, 58 masses underwent with transvaginal CEUS, and 15 masses underwent both transvaginal and transabdominal CEUS. All patients were scheduled for surgery and pathological results served as the reference standard. Routine Doppler ultrasound and CEUS images and video were reviewed by a subspecialty radiologist using Vuebox software. The O-RADS US was downgraded or upgraded according to the CEUS characteristics of the masses. The diagnostic accuracy was assessed using ROC curve analysis. The area under the ROC curve (AUC) was calculated to compare the diagnostic performance of adding value of transabdominal and transvaginal CEUS to O-RADS US.Results:The diagnostic performance of adding transabdominal and transvaginal CEUS to O-RADS US were both significantly higher than of O-RADS US alone (transabdominal CEUS: AUC 0.83 vs 0.76, P=0.018; transvaginal CEUS: AUC 0.92 vs 0.81, P=0.013). Combination of transvaginal CEUS and O-RADS US was superior to that of combination of transabdominal and O-RADS US in the differential diagnosis of adnexal masses ( P=0.047). When the maximal diameter of adnexal masses ≤40 mm, transabdominal combined with O-RADS US presented the lowest diagnostic performance, with an AUC of 0.73. Conclusions:Combination of transvaginal CEUS and O-RADS US was superior to that of combination of transabdominal and O-RADS US in assessing adnexal masses with solid components. When the maximal diameter of adnexal masses ≤40 mm, transvaginal CEUS examination was recommended.

Four pyrazines were isolated from the n-butanol fraction of Hypecoum erectum L. by using various chromatographic methods, including MCI gel, ODS, silica gel and semi-preparative HPLC. The structures of the isolated compounds were identified as hyperectpyrazin A (1), 1′S-(6-methylpyrazin-2-yl)-ethane-1′,2′-diol (2), 2-hydroxymethyl-6-methylpyrazin (3) and pyrazine-2-carboxylic acid (4) by spectroscopy methods (1D NMR, 2D NMR, UV, IR, MS, etc.). The absolute configuration of compound 2 was determined by using the Mo₂(OAc)₄ induced CD analysis for the first time. Compound 1 was a new compound, compounds 2-4 were isolated from H. erectum for the first time. Compounds 1-4 were evaluated for their inhibition against acetylcholinesterase and nitric oxide generation induced by lipopolysaccharide-RAW264.7 macrophage cells. At a concentration of 50 μmol·L^-1, compounds 2 and 4 displayed inhibitory effects on acetylcholinesterase with the inhibition rates of 44.40% and 43.99%, respectively.

【Objective】 To investigate the prevalence and influencing factors of overweight and obesity among preschool children in Suzhou. 【Methods】 A stratified cluster random sampling method was used to select 24 452 children aged 3 - 6 years in different districts of Suzhou from December 2021 to June 2022. Then the prevalence rate of overweight and obesity was determined by physical measurements. A case-control study was conducted with a questionnaire survey of 3 786 children(1 893 in the obesity group and 1 893 in the control group) to analyze the factors influencing preschool obesity. 【Results】 1) The overall detection rates of overweight among preschool children in Suzhou was 14.8%(boys 14.6%, girls 15.0%). The overall detection rates of obesity was 7.9%(boys 8.7%, girls 7.1%), with a statistically significant difference between boys and girls(χ²=19.828, P<0.01). 2) There was statistically significant difference in the detection rates of obesity among different age groups(χ²=98.415, P<0.01), with the lowest rate in the 3 - 4 years old group(5.8%) and the highest rate in the 6 - 7 years old group(11.8%). 3) The overall detection rates of mild, moderate and severe obesity was 4.8%, 2.6% and 0.5%, respectively. The proportion of moderate and severe obesity significantly increased with age(χ²=57.275, P<0.01). 4) Risk factors for preschool obesity included birth weight >4 000g, cesarean section, parental overweight/obesity, strong appetite of children, eating speed <10min/meal, high frequency of fried food consumption(>1time/week), eating while watching television, sedentary behavior >2h/d, insufficient exercise endurance, screen time >1h/d, and late bedtime(after 21∶30)(P<0.05). Protective factors for preschool obesity included larger breakfast consumption, fruits and vegetables as regular snacks, and physical activity after meals(P<0.05). 5) Factors influencing the degree of preschool obesity included paternal overweight(OR=1.33, 95%CI:1.06 - 1.65), paternal obesity(OR=1.91, 95%CI:1.46 - 2.49), maternal overweight(OR=1.25, 95%CI:1.01 - 1.54), maternal obesity(OR=1.94, 95%CI:1.40 - 2.69), low education level of father(junior high school or below)(OR=1.57, 95%CI:1.25 - 1.96), strong appetite of children(OR=1.72, 95%CI:1.41 - 2.11), eating speed <10min/meal(OR=1.29, 95%CI:1.05 - 1.57), sedentary behavior >2h/d(OR=1.51, 95%CI:1.24 - 1.85), insufficient exercise endurance(OR=1.56, 95%CI:1.12 - 2.19), and screen time>1h/d(OR=1.42, 95%CI:1.16 - 1.75). 【Conclusions】 The detection rates of overweight and obesity among preschool children in Suzhou are relatively high, and the detection rate and severity of obesity increase with age. In addition to genetic factors, preschool obesity are also associated with pregnancy and birth history, as well as unhealthy lifestyle after birth.