ObjectiveTo analyze the epidemiological characteristics and spatial clustering patterns of brucellosis in humans in Zhangjiakou City, Heibei Province from 2018 to 2023, so as to provide a basis for the prevention and control of brucellosis. MethodsIncidence data of brucellosis in Zhangjiakou City from 2018 to 2023 were collected. Descriptive epidemiological analysis, Joinpoint regression modelling, and spatial autocorrelation analysis were used to analyze the temporal trends and spatial clustering patterns of the epidemic. ResultsA total of 3 812 cases of brucellosis were reported in Zhangjiakou City from 2018 to 2023, with no death case, yielding an average annual incidence rate of 15.43/100 000 (incidence range: 12.82/100 000‒17.76/100 000). Cases of brucellosis occurred year-round, with a distinct seasonal pattern, predominantly concentrated between March and September, peaking in May and June. The male-to-female ratio was 2.58∶1, with a higher incidence in males than that in females. The highest incidence rates were observed in the 40‒<50 years (74.98/100 000) and 50‒<60 years age group (87.14/100 000). The majority of cases were farmers and herdsmen (3 557 cases, 93.31%). Joinpoint regression analyses indicated that from 2018 to 2023, the incidence rate of human brucellosis in pastoral areas of Zhangjiakou City showed a declining trend (APC=-9.70%, 95%CI: -15.31%‒ -4.63%), while the incidence rate in mixed-use areas exhibited an increasing trend (APC=6.90%, 95%CI: 0.17%‒14.30%). Spatial clustering analyses showed that the incidence of brucellosis in Zhangjiakou from 2018 to 2023 was non-randomly distributed across the whole city, with a positive spatial correlation and significant clustering (Moran’s I>0, all P<0.001). Local spatial autocorrelation analyses showed that the high-high clusters were concentrated in the pastoral areas during 2018‒2020. From 2021 onward, the number of high-high clusters in mixed and non-pastoral regions exceeded those in traditional pastoral areas. ConclusionFrom 2018 to 2023, the incidence of brucellosis in Zhangjiakou City showed a declining trend, with significant spatial clustering observed across the city. It is recommended to intensify health education among males aged 40‒<60 years. Scientific livestock management practices should be promoted in non-pastoral and mixed areas, and cross-sectoral quarantine and joint prevention and control efforts should be strengthened as well.

Objective:To explore the clinical and genetic characteristics of three children with Hyperekplexia.Methods:Three children who were diagnosed with Hyperekplexia at the Third Affiliated Hospital of Zhengzhou University between June 2018 and March 2020 were selected as the study subjects. Clinical data of the three children were collected. All children were subjected to whole exome sequencing. Pathogenicity of candidate variants were verified by Sanger sequencing and bioinformatic analysis.Results:The three children were all males, and had presented exaggerated startle reflexes and generalized stiffness in response to unexpected auditory or tactile stimulation, or had frequent traumatic falls following exaggerated startle. All children had shown positive nose-tapping reflex, though EEG and cranial MRI exams were all negative. Whole exome sequencing revealed that two children had harbored homozygous variants of the GLRB gene, of which the c. 1017_c.1018insAG (p.G340Rfs*14) was unreported previously. The third child had harbored compound heterozygous variants of the GLRA1 gene, among which the c.1262T>A (p.IIe421Asn) variant showed an unreported autosomal recessive inheritance. All children had responded well to clonazepam treatment. Conclusion:Patients with Hyperekplexia have typical clinical manifestations. Early clinical identification and genetic analysis can facilitate their diagnosis.

Objective:To analyze the drug resistance characteristics of Klebsiella pneumoniae in the nasopharynx of hospitalized patients in North China from 2022 to 2023. Methods:From November 2022 to July 2023, nasopharyngeal swabs were collected from 100 inpatients in Affiliated Hospital of North China University of Science and Technology, and Klebsiella pneumoniae was isolated and cultured. At the same time, the clinical data of the patients were collected, including gender, age, department, clinical diagnosis of disease type, etc. The minimum inhibitory concentration of strains was detected by an automatic bacterial drug sensitivity system. The drug resistance genes, ST types, capsule serotypes and population structure of the strains were analyzed by whole genome sequencing and data analysis. Results:Klebsiella pneumoniae was isolated from 55 nasopharyngeal swabs of 100 inpatients(55.00%). Among the 55 inpatients with Klebsiella pneumoniae in the nasopharynx, 70.91% (39/55) were male, with an age distribution concentrated between 61 and 80 years old (58.18%, 32/55), and 50.91% (28/55) were in intensive care units (ICU). The main underlying disease type was nervous system disease (49.09%, 27/55). The results of drug sensitivity showed that the non-susceptibility rates of 55 strains of Klebsiella pneumoniae to cephalosporins, quinolones, aztreonam and nitrofurantoin were all more than 80.00%. Twenty-eight carbapenem-resistant Klebsiella pneumoniae strains (50.91%), 47 extended-spectrum β-lactamase producing strains (85.45%), and 48 multi-drug-resistant strains (87.27%) were detected. A total of 11 antibiotic resistance genes were detected, including carbapenems (carrying rate 76.36%) and extended-spectrum β-lactamase (carrying rate 96.36%). The 55 strains could be divided into 17 ST types, and the most common type was ST11 (25.45%). The 55 strains were divided into 18 capsular serotypes, among which K102 was the most prevalent (23.64%). OXA-1_ST307_K102 (21.82%) and KPC-2_ST5492_K125 (18.18%) were the dominant clones, distributed in the Department of Neurosurgery and ICU. The result of whole genome sequence analysis showed that there were four clusters with high homology among the 55 strains. The strains from the ICU formed two independent clusters, and strains from the Neurology ICU and Neurosurgery department formed one cluster respectively. Conclusion:The carrying rate of Klebsiella pneumoniae in the nasopharynx of inpatients is high, and the drug resistance of the strains is serious. There are many types of drug-resistant genes.

Objective To detect and analyze the drug resistance characteristics,phylogenetic typing,and virulence gene distribution of Escherichia coli(E.coli)in blood culture.Methods The strains of E.coli isolated from consecutive non-repetitive blood cultures in our hospital from January 1,2019 to December 13,2020 were collected.The sensitivity of E.coli to 17 antibiotics was determined u-sing the micro-broth method.The bacterial genomic DNA was extracted using the boiling method,and then the arpA,chuA,yjaA,TspE4C2,ArpAgpE and trpAgpC genes were detected by PCR to determine the bacterial phylogroup.The virulence genes,including iutA,fimH,fyuA,kpsMT Ⅱ,cnf1,cvac,hlyA,traT,kpsMT Ⅲ,and PAI,were detected using the multiplex PCR.The differences in drug resistance and virulence gene distribution among different phylogroups were analyzed by the Chi-square test.Results 270 strains of E.coli in blood culture showed high resistance rates to ceftriaxone,compound sulfamethoxazole,ampicillin,ampicillin sulbactam,cefazolin,and ciprofloxacin,all exceeding 50.0％.They had good susceptibility to imipenem,ertapenem,amikacin,and piperacillin tazobactam,with resistance rates all below 5.0％.The most common phylogroups were types B2 and D,accounting for 38.0％and 16.2％,respectively,while type E and hidden branch type I were relatively rare,accounting for less than 1.0％.The virulence gene analysis revealed that the distribution rates of fimH and fyuA genes were the highest,both above 99.0％.The distribution rates of kpsMT Ⅲ,hlyA,and cvaC genes were relatively low,all below 20.0％.The Chi-square test showed that the distribution rates of viru-lence genes such as iutA,fimH,fyuA,kpsMT Ⅱ,cnf1,and PAI in the B2 group were significantly higher than those in the non-B2 group(P<0.05).The distribution rates of iutA,fyuA,kpsMT Ⅱ,cnf1,and PAI genes in the B2 group were significantly higher than those in the D group(P<0.05).Conclusion When treating bloodstream infections caused by E.coli,caution should be exercised in the use of drugs such as ceftriaxone,compound sulfamethoxazole,ampicillin,ampicillin sulbactam,cefazolin,and ciprofloxacin.When bloodstream infections are caused by phylogroup B2 E.coli,middle-stream urine culture should be performed simultaneously to confirm the source of infection and monitor the success rate of treatment.

Objective To evaluate the ability of average nucleotide identity(ANI)and 16S rDNA technology on the identification of Salmonella.Methods The genomes and corresponding serovars of global Salmonella were downloaded in batch from the GenBank database.The classical strains of Salmonella were used as typing strains.The ANI analysis was conducted by the fastANI software according to the silent parameters.The species and serovars of Salmonella were identified by their 16S rDNA using the online software SpeciesFinder.Results Among the downloaded 2 306 genomes,1 767 strains of Salmonella had 178 serovars,with 323 strains(18.3%)of Salmonella Typhimurium and 300 strains(17.0%)of Salmonella Enteritidis being the most common.The ANI analysis showed that with a 95%threshold,only 30 strains(1.3%)of Salmonella were assigned to a specific subspecies,while the remaining 2 276 strains(98.7%)of Salmonella could be assigned to 2-5 subspecies.When the threshold was 97%,all 2 306 strains(100%)of Salmonella could be assigned to a specific subspecies.Based on the analysis of 16S rDNA,only 1 072 strains(46.5%)of Salmonella were identified,of which 95.2%(1 021/1 072)of Salmonella subspecies were completely consistent with the results of ANI(≥97%)analysis.Only 2.4%(19/784)of Salmonella strains showed consistent results with known serovars.Conclusion ANI is more suitable for the identification of Salmonella species and subspecies,and ANI≥97%can be used as the identification standard for Salmonella subspecies.The sensitivity of 16S rDNA for the identification of Salmonella still needs to be improved.

Objective To analyze the epidemiological characteristics of mobile colistin resistance(mcr)genes in global Klebsiella pneumoniae(K.pneumoniae).Methods The genomes of K.pneumoniae were downloaded from the NCBI genome database by the As-pera software.After quality filtering using the CheckM v1.1.3 and Quest 5.0.2 software,the genomes were annotated using the Prokka v1.13.All the mcr gene sequences were downloaded from the NCBI website and a database was built using the makeblastdb command.Then,a self-made Perl script program was used to extract the nucleotide sequences of all genes from the annotation file as Query,and the local BLASTN analysis was performed to obtain mcr-positive strains.The gene sequence files and Profiles files of 7 housekeeping genes of K.pneumoniae were downloaded from the PubMLST website as the database,and the nucleotide sequences of the genes were extracted as Query using a self-made Perl script program.The local BLASTN analysis was implemented to determine the sequence type(ST)of each genome.Meta information of each strain,including isolation source,sample type,country,and date,were extracted in batch from the GenBank file of the downloaded K.pneumoniae genomes using a self-written Perl program to analyze the distribution characteristics of mcr-positive strains.The distribution differences of the mcr between different ST types were compared by the Chi-square test.Results Among the 11 429 global K.pneumoniae genomes included in this study,229 mcr genes were detected from 207 strains.Six variants of mcr were identified,mainly mcr-1(87/229,38.0％),mcr-8(59/229,25.8％),and mcr-9(59/229,25.8％).76 STs were identified from 207 strains,with ST15(21/207,10.1％),ST43(17/207,8.2％),ST11(16/207,7.7％),and ST 147(16/207,7.7％)being the predominant.Among 87 mcr-1 positive strains,31 STs were found,with ST43(17/87,19.5％)and ST15(10/87,11.5％)being the main ones.Among 59 mcr-8 positive strains,17 STs were identified,with ST43(17/59,28.8％)and ST11(9/59,15.3％)being the predominant.Among 59 mcr-9 positive strains,27 STs were detected,with ST147(11/59,18.6％)and ST274(11/59,18.6％)being the main ones.There were statistical differences in the variants of mcr genes carried by different ST types.The mcr-positive K.pneumoniae came from 28 countries across five continents worldwide,led by China(68/207,32.9％)and Thailand(45/207,21.7％),which were mainly from the human body(100/207,48.3％)and had a concentrated outbreak time from 2015 to 2018.Conclusion Among the global K.pneumoniae,the prevalence of mcr is mainly domina-ted by mcr-1,mcr-8,and mcr-9.The dominant clones of mcr-1 are mainly ST15 and ST43,while those of mcr-8 are mainly ST11 and ST43.The popularity of mcr-9 is mainly based on ST147 and ST274.Strengthening the monitoring of such bacteria may play an impor-tant role in preventing and controlling nosocomial infections.

Objective To analyze the prevalence and molecular characteristics of global Salmonella Typhimurium.Method The ge-nome and the corresponding serovars as well as meta-information of global Salmonella were downloaded in batch from the National Cen-ter for Biotechnology Information(NCBI)database using the online softwares,ResFinder,PlasmidFinder,Mobile Element Finder and MLST,to analyze the distribution of antibiotic resistant genes(ARGs),plasmids,mobile genetic elements(MGEs)and the sequence types(STs)among S.Typhimurium strains.Results A total of 101 ARGs were detected in 323 strains of S.Typhimurium,among which the most common was aac(6')-Iaa(322/323,99.69％),followed by sul2(155/323,47.99％),aph(3")-Ib(128/323,39.63％),aph(6)-Id(127/323,39.32％),tet(B)(109/323,33.75％),and blaTEM-1B(106/323,32.82％).Totally,36 plasmids were identified,among which IncFⅡ(S)(110/323,34.06％)and IncFⅠB(S)(108/323,33.44％)were the most common.Moreo-ver,376 MGEs were found,including 367 insertion sequences and nine transposons,among which MITEEc1(322/323,99.69％)and ISSen1(308/323,95.36％)were the most popular.Furthermore,323 strains of S.Typhimurium were assigned into 32 different STs,a-mong which,ST19(157/323,48.61％)and ST34(105/323,32.51％)were the most common accounting for over 82％.Among 115 strains of S.Typhimurium from human,18 STs were identified including ST19(52/115,45.22％)and ST34(39/115,33.91％)which were the most common.Conclusion S.Typhimurium carried multiple types of ARGs,in addition to the wide distribution of a large number of insertion sequences and plasmids,whch provide favorable conditions for the spread of drug resistance.Therefore,the meas-ures of prevention and control against the infection from this bacterium should be strengthened.

Objective To develop and validate a prediction model for severe disability or death(SDD)in acute ischemic stroke(AIS)patients who underwent endovascular treatment(EVT).Methods Based on the dataset of ANGEL-ACT study who received EVT for AIS between november 2017 and march 2019,a retrospective analysis was performed on 1 677 patients,including 1 111 males and 566 females,aged ≥ 18 years.Patients were divided into two groups according to whether SDD occurred(mRS 5-6 scores 90 days after surgery):SDD group(n=478)and non-SDD group(n=1 199).Risk factors that might influence SDD after EVT in AIS patients were screened and analyzed by multifactorial analysis,LAS-SO regression,and RF-RFE methods.A nomogram was developed after evaluating the model performance and the execution of internal validation.Results SDD occurred in 380(28.1％)patients in the develop-ment cohort and 98(30.2％)patients in the validation cohort.Combining the three variable screening meth-ods,10 risk factors were selected for inclusion in the final model:age,NIHSS score,whether successful re-canalization,glucose level,hemoglobin,hematocrit,onset to puncture time,systolic blood pressure,AS-PECT score,and whether have treatment-related serious adverse events.A two-stage model means that model 1 contains pre-treatment variables(7 in total)and model 2 contains pre-treatment and post-treatment variables(10 in total).The area under the curve(AUC)of model 1 in the development cohort was 0.705(95％CI 0.674-0.736)and 0.731(95％CI 0.701-0.760)in model 2.Both models had good calibration with aslope of 1.000,and the decision curve analysis showed good clinical applicability.The results of the validation cohort were similar to those of the development cohort.Conclusion Age,admission NIHSS score,whether successful recanalization,admission glucose level,hemoglobin content,erythrocyte pressure volume,onset to puncture time,admission systolic blood pressure,ASPECT score,and whether have treat-ment-related serious adverse events are risk factors for SDD in patients with acute ischemic stroke.The two prediction models based on the above factors were used before and after endovascular treatment to predict SDD occurrence better.

Objective:To assess the capability of seven reference medical laboratories to detect BCR::ABL1 p210 transcription levels and to compare the results among those laboratories.Methods:The interlaboratory comparison was carried out in two stages. The samples were prepared by the reference laboratory. The quantitative values of BCR::ABL1 p210 of the comparison samples covered 0.001%-0.01%, 0.01%-0.1%, 0.1%-1%, 1%-10% and>10% in each stage. Real-time quantitative PCR (RT-PCR) and dPCR (digital PCR) were used to examine the samples. The conversion factor (CF) was calculated and validated for each laboratory.Results:In the RT-PCR comparison, one laboratory was failed to detect BCR::ABL1 p210 in fourteen samples at the first stage. The results of the other six laboratories were qualified with the bias <±1.2 folds (-0.133-0.338) and 95% limits of agreement within ±5 folds (upper limit 0.147-0.785, lower limit -0.770--0.109), and the corresponding CF values were calculated and validated. In the dPCR comparison, one laboratory did not report results at the second stage. The results of the other six laboratories were qualified with the bias <±1.2 folds (-0.026-0.267) and 95% limits of agreement within±5 folds (upper limit 0.084-0.991, lower limit -0.669--0.135), and the corresponding CF values were calculated and validated. The samples with BCR::ABL1 p210 quantitative values of 0.01%-0.1%, 0.1%-1%, 1%-10% and >10% could be detected by both RT-PCR and qPCR. When the quantitative value of BCR::ABL1 p210 was 0.001%-0.01%, the detection rate of dPCR was higher than that of RT-PCR (85.56% vs. 68.00%).Conclusions:A good consistency is present among various laboratories. The quantitative value of BCR::ABL1 p210 is comparable among laboratories as shown by the CF value conversion. For quantitative detection of BCR::ABL1 p210 deep molecular reaction, dPCR has a higher positive detection rate and more advantages than RT-PCR. To ensure the accuracy and reproducibility of the BCR::ABL1 p210 test, it is imperative for every laboratory to enhance their daily quality control practices.

Objective:To retrospectively analyze the treatment status of tyrosine kinase inhibitors (TKI) in newly diagnosed patients with chronic myeloid leukemia (CML) in China.Methods:Data of chronic phase (CP) and accelerated phase (AP) CML patients diagnosed from January 2006 to December 2022 from 77 centers, ≥18 years old, and receiving initial imatinib, nilotinib, dasatinib or flumatinib-therapy within 6 months after diagnosis in China with complete data were retrospectively interrogated. The choice of initial TKI, current TKI medications, treatment switch and reasons, treatment responses and outcomes as well as the variables associated with them were analyzed.Results:6 893 patients in CP ( n=6 453, 93.6%) or AP ( n=440, 6.4%) receiving initial imatinib ( n=4 906, 71.2%), nilotinib ( n=1 157, 16.8%), dasatinib ( n=298, 4.3%) or flumatinib ( n=532, 7.2%) -therapy. With the median follow-up of 43 ( IQR 22-75) months, 1 581 (22.9%) patients switched TKI due to resistance ( n=1 055, 15.3%), intolerance ( n=248, 3.6%), pursuit of better efficacy ( n=168, 2.4%), economic or other reasons ( n=110, 1.6%). The frequency of switching TKI in AP patients was significantly-higher than that in CP patients (44.1% vs 21.5%, P<0.001), and more AP patients switched TKI due to resistance than CP patients (75.3% vs 66.1%, P=0.011). Multi-variable analyses showed that male, lower HGB concentration and ELTS intermediate/high-risk cohort were associated with lower cytogenetic and molecular responses rate and poor outcomes in CP patients; higher WBC count and initial the second-generation TKI treatment, the higher response rates; Ph + ACA at diagnosis, poor PFS. However, Sokal intermediate/high-risk cohort was only significantly-associated with lower CCyR and MMR rates and the poor PFS. Lower HGB concentration and larger spleen size were significantly-associated with the lower cytogenetic and molecular response rates in AP patients; initial the second-generation TKI treatment, the higher treatment response rates; lower PLT count, higher blasts and Ph + ACA, poorer TFS; Ph + ACA, poorer OS. Conclusion:At present, the vast majority of newly-diagnosed CML-CP or AP patients could benefit from TKI treatment in the long term with the good treatment responses and survival outcomes.