Objective:To investigate the genetic causes of fetuses with abnormal nasal bone development in early pregnancy.Methods:A retrospective study was conducted which involved 422 cases of singleton pregnancies with nasal bone development abnormalities indicated by ultrasound screening at 11 to 13 weeks and 6 days of gestation, who underwent chorionic villus sampling for prenatal diagnosis at the Prenatal Diagnosis and Genetic Center, Maternity & Child Health Hospital of Guangxi Zhuang Autonomous Region from January 2015 to May 2023. All cases underwent chromosomal karyotype analysis and single nucleotide polymorphism array (SNP-array) analysis. Based on whether other abnormal ultrasound indicators were present, the cases were divided into isolated (175 cases) and non-isolated groups (247 cases). The results of invasive prenatal diagnosis, distribution of chromosomal abnormalities, detection of copy number variation (CNV) in fetuses with nasal bone development abnormalities, the relationship between maternal age, number of abnormal ultrasound indicators and chromosomal abnormalities, and pregnancy outcomes were analyzed. Statistical analysis was performed using the Chi-square test (continuity correction Chi-square test or Fisher's exact test). Results:(1) Among the 422 cases, 262 cases (62.1%) showed no abnormalities with both detection techniques; 160 cases had abnormalities, including 145 cases (34.4%) had consistent abnormal results and types of abnormalies with the two techniques; two cases (0.5%) had chromosomal translocations detected by karyotype analysis but not by SNP-array analysis; 13 cases (3.1%) had no abnormalities detected by karyotype analysis but had abnormal SNP-array results. This study's overall detection rate of chromosomal abnormalities was 37.9% (160/422), with an additional detection rate of 4.7% (13/275) using SNP-array technology. (2) Among the 160 cases of chromosomal abnormalities, there were 140 cases of aneuploidy, 18 cases of CNV, and two cases of chromosomal translocation. The overall detection rate of chromosomal abnormalities and the detection of aneuploidy, and pathogenic CNV in the non-isolated group was higher than that in the isolated group [74.3% (130/175) vs. 12.1% (30/247), χ2=168.02; 68.0% (119/175) vs. 8.5% (21/247), χ2=163.56; 5.7% (10/175) vs. 0.8% (2/247), χ2=4.74; all P<0.05]. Eighteen cases of CNV were detected using SNP-array technology, including eight cases in the isolated group and ten cases in the non-isolated group. (3) The age of the 422 pregnant women was (33.1±5.4) years. In both isolated and non-isolated groups, the detection rate of chromosomal abnormalities was higher in women of advanced age (expected delivery age ≥35 years) than those not [isolated group: 20.0% (17/85) vs. 8.6% (14/162), χ2=6.55; non-isolated group: 82.1% (69/84) vs. 65.9% (60/91), χ2=5.92; both P=0.010]; regardless of maternal age, the detection rate of chromosomal abnormalities in the non-isolated group was significantly higher than that in the isolated group ( χ2 were 65.28 and 92.42, respectively, both P<0.001). (4) In the non-isolated group, the detection rates of chromosomal abnormalities were 69.0% (78/113) and 83.9% (52/62) when nasal bone abnormalities were combined with one or more other abnormal ultrasound indicators, respectively. When combined with increased nuchal translucency, the detection rate of fetal chromosomal abnormalities was 73.2% (71/97), higher than the detection rate when combined with other single indicators (7/16) ( χ2=5.57, P=0.020). (5) Among the 262 cases with negative karyotype analysis and SNP-array results, 241 cases (92.0%) resulted in live births, with a gestational age at delivery of 39 weeks (32-41 weeks); 12 cases (4.6%) resulted in induced labor, five cases (1.9%) resulted in miscarriage, and four cases (1.5%) were lost to follow-up. The live birth rate in the isolated group was higher than that in the non-isolated group [86.9% (213/245) vs. 20.2% (35/173), χ2=187.00, P<0.001]. Conclusions:Fetuses with nasal bone developmental abnormalities in early pregnancy have a higher detection rate of chromosomal abnormalities and CNV. Invasive prenatal diagnosis is recommended for cases of nasal bone developmental abnormalities in early pregnancy, whether isolated or non-isolated. When combined with other abnormal indicators, the genetic etiology of the fetus is more complex, and detailed genetic counseling should be provided to the patient.

Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

Objective This study aimed to investigate the antimicrobial resistance profiles of bacterial strains isolated from pediatric intensive care units(PICU)in China for better antimicrobial therapy.Methods Clinical isolates were collected from 17 institutions,including tertiary care children's hospitals and pediatric department of tertiary general hospitals in China from January 1,2020 to December 31,2022.Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems.Results were interpreted according to the breakpoints released by the Clinical and Laboratory Standards Institute(CLSI)in 2020.Results A total of 10 688 isolates were collected,including gram-positive organisms(39.2％)and gram-negative organisms(60.8％).The top three organisms were S.aureus(13.6％,1 453/10 688),A.baumannii(10.0％,1 067/10 688),and coagulase-negative Staphylococcus(9.9％,1 058/10 688).Multi-drug resistant organisms(MDROs)were very common in children.The prevalence of methicillin-resistant Staphylococcus aureus(MRSA),carbapenem-resistant Enterobacterales(CRE),carbapenem-resistant E.coli,carbapenem-resistant K.pneumoniae(CRKP),carbapenem-resistant A.baumannii(CRAB),and carbapenem-resistant P.aeruginosa(CRPA)was 41.1％,19.4％,8.8％,30.9％,67.4％,and 28.8％,respectively.Overall,more than 50％of Enterobacteriales isolates were resistant to cephalosporins,while nearly 25％of Enterobacteriales isolates were resistant to carbapenems.MDROs were highly resistant to commonly used antibiotics.More than 80％of CRE and CRAB strains were resistant to all beta-lactam antibiotics.CRE and CRAB showed low resistance rates to tigecycline and polymyxin.CRPA showed lower resistance rates to piperacillin,beta-lactamase inhibitor combinations than the resistance rates to third and fourth generation cephalosporins.All of the Staphylococcus and Enterococcus isolates were susceptible to vancomycin and tigecycline.None of PRSP strains isolated from meningitis and nonmeningitis samples were resistant to rifampicin,vancomycin,or linezolid.The prevalence of β-lactamase-negative ampicillin-resistant(BLNAR)strains was 43.3％in Haemophilus influenzae.Conclusions MDROs were prevalent in PICU.It is necessary to establish an effective multidisciplinary team(MDT)to control the antimicrobial resistance.

Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

Objective This study aimed to investigate the antimicrobial resistance profiles of bacterial strains isolated from pediatric intensive care units(PICU)in China for better antimicrobial therapy.Methods Clinical isolates were collected from 17 institutions,including tertiary care children's hospitals and pediatric department of tertiary general hospitals in China from January 1,2020 to December 31,2022.Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems.Results were interpreted according to the breakpoints released by the Clinical and Laboratory Standards Institute(CLSI)in 2020.Results A total of 10 688 isolates were collected,including gram-positive organisms(39.2％)and gram-negative organisms(60.8％).The top three organisms were S.aureus(13.6％,1 453/10 688),A.baumannii(10.0％,1 067/10 688),and coagulase-negative Staphylococcus(9.9％,1 058/10 688).Multi-drug resistant organisms(MDROs)were very common in children.The prevalence of methicillin-resistant Staphylococcus aureus(MRSA),carbapenem-resistant Enterobacterales(CRE),carbapenem-resistant E.coli,carbapenem-resistant K.pneumoniae(CRKP),carbapenem-resistant A.baumannii(CRAB),and carbapenem-resistant P.aeruginosa(CRPA)was 41.1％,19.4％,8.8％,30.9％,67.4％,and 28.8％,respectively.Overall,more than 50％of Enterobacteriales isolates were resistant to cephalosporins,while nearly 25％of Enterobacteriales isolates were resistant to carbapenems.MDROs were highly resistant to commonly used antibiotics.More than 80％of CRE and CRAB strains were resistant to all beta-lactam antibiotics.CRE and CRAB showed low resistance rates to tigecycline and polymyxin.CRPA showed lower resistance rates to piperacillin,beta-lactamase inhibitor combinations than the resistance rates to third and fourth generation cephalosporins.All of the Staphylococcus and Enterococcus isolates were susceptible to vancomycin and tigecycline.None of PRSP strains isolated from meningitis and nonmeningitis samples were resistant to rifampicin,vancomycin,or linezolid.The prevalence of β-lactamase-negative ampicillin-resistant(BLNAR)strains was 43.3％in Haemophilus influenzae.Conclusions MDROs were prevalent in PICU.It is necessary to establish an effective multidisciplinary team(MDT)to control the antimicrobial resistance.

Objective:To investigate the effect of monocular form deprivation (MD) during the pre-critical period of visual development on the density and morphology of dendritic spines in mouse primary visual cortex (V1) neurons.Methods:Twenty SPF male C57BL/6J mice with eyes opened on postnatal day 14 (P14) were selected and divided into MD and control groups using a random number table, with 10 mice in each group.The MD group was fed to P18 after 4 days of MD in the right eye, and the control group was raised to P18 under the same feeding conditions.All mice were decapitated after cardiac perfusion, and the sections were stained with the cell membrane fluorescent probe 1, 1′-dioctadecyl-3, 3′, 3′-tetramethylindocarbocyanine perchlorate, and imaged by laser scanning confocal microscopy to observe and compare the differences in density and morphology of dendritic spines in bilateral V1 neurons between the control group and the MD group.This study was approved by the Animal Ethics Committee of Tianjin Medical University (No.TMUaMEC2022004).Results:The total density of dendritic spines in the V1 area on the left side of the control group, the right side of the control group, the left side of the MD group, and the right side of the MD group were (7.57±0.25), (7.42±0.25), (6.54±0.18), and (7.51±0.29)spines/10 μm, respectively, with a statistically significant overall difference ( F=3.818, P<0.05).The total density of dendritic spines in the left V1 area of mice in the MD group was significantly lower than that in the left side of the control group and the right side of the MD group, and the differences were statistically significant (both P<0.05).There was a significant difference in the proportion of the four types of dendritic spines in V1 neurons on both sides between the two groups ( χ2=26.295, P=0.002).There was a significant difference in the proportion of the four types of dendritic spines between the left V1 of the MD group and the left and right V1 of the control group (both P<0.008 3).There was a significant difference in the filopodia-type dendritic spine density in bilateral V1 neurons between the two groups ( F=3.253, P<0.05).Compared with the left V1 area of the control group, the density of filopodia-type dendritic spines in the left V1 area of the MD group decreased significantly, with a statistical significance ( P<0.05).There was no significant difference in the density of thin-type, mushroom-type, and stubby-type dendritic spines in bilateral V1 area neurons between the two groups ( F=1.760, 2.618, 1.749; all P>0.05). Conclusions:MD during the pre-critical period of visual development can cause a decrease in the total density of dendritic spines and significant changes in the compositional proportions in the V1 contralateral to the deprived eye, and is mainly manifested by a decrease in the number of filopodia, suggesting that abnormal visual experience can cause plastic changes in the number and structure of synapses in the visual cortex during the pre-critical period of visual development.

Objective:To explore the clinical application value of multimodal Magnetic Resonance Imaging(MRI)in cognitive impairment related to Cerebral Small Vessel Disease(CSVD).Methods:This study was a retrospective analysis of 60 CSVD patients,who were divided into cognitive impairment group(n=32)and normal group(n=28)based on Montreal Cognitive Assessment scale(MoCA).Compare the general information and MRI parameters of two groups of patients,use correlation analysis and logistic regression analysis to investigate the relationship between MRI parameters and cognitive dysfunction,and use receiver operating characteristic curve(ROC)to explore the value of MRI parameters in diagnosing cognitive dysfunction in cerebral small vessel disease.Results:Compared with the cognitively normal group,the cognitive impairment group had older age,higher apparent diffusion coefficient(ADC),lower anisotropy score(FA),and an overall increase in microbleeds(P＜0.05).Age(r=-0.510),ADC value(r=-0.591),and overall number of microbleeds(r=-0.369)were significantly negatively correlated with MoCA score(P＜0.05),while FA value(r=0.262)was significantly positively correlated with MoCA score(P＜0.05).The logistic regression results indicate that age,overall microbleeds,ADC value,and FA value are influencing factors for cognitive impairment in patients with cerebral small vessel disease.ROC curve analysis showed that the combination of age,ADC,FA,and microbleeds significantly improved diagnostic efficacy(AUC=0.990,95％CI=0.974-1.000).Conclusion:The joint analysis of multimodal MRI parameters can provide important imaging evidence for the early identification of cognitive dysfunction in CSVD.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.