Serotype distribution and antimicrobial resistance of pediatric Streptococcus pneumoniae isolated from inpatients and outpatients at Beijing Children's Hospital

Abstract Background Understanding the epidemiology of Streptococcus pneumoniae (S. pneumoniae) isolates is important for pneumonia treatment and prevention. This research aimed to explore the epidemiological characteristics of S. pneumoniae isolated from pediatric inpatients and outpatients during the same period. Methods S. pneumoniae were isolated from unsterile samples of inpatients and outpatients younger than five years old between March 2013 and February 2014. The serotypes were determined using diagnostic pneumococcal antisera. The resistance of each strain to 13 antibiotics was tested using either the E-test or the disc diffusion method. The Sequence Types (STs) were analyzed via Multilocus Sequence Typing (MLST). Results The dominant serotypes obtained from inpatients were 19F (32.9 %), 19A (20.7 %), 23F (10.7 %), 6A (10.0 %), and 14 (8.6 %), while those from outpatients were 19F (13.6 %), 23F (12.9 %), 6A (10.0 %), 6B (10.0 %), and 19A (7.9 %). The coverage rates of 13-valent Pneumococcal Conjugate Vaccine (PCV) formulations were high in both groups. The nonsusceptibility to penicillin, cefuroxime, imipenem, erythromycin, and trimethoprim-sulfamethoxazole among the inpatient isolates was 7.1 %, 92.8 %, 65.7 %, 100 %, and 85.0 %, respectively, while that among the outpatient isolates was 0.7 %, 50.0 %, 38.6 %, 96.4 %, and 65.7 %, respectively. There were 45 and 81 STs detected from the pneumococci isolated from inpatients and outpatients, respectively. CC271 was common among both inpatients and outpatients (43.6 % and 14.3 %). Conclusions Pneumococcal vaccine-related serotypes are prevalent among both inpatients and outpatients, especially among inpatients, who exhibit more severe antibiotic resistance. Therefore, universal immunization with PCV13 would decrease the hospitalization rate due to S. pneumoniae and the antibiotic resistance rate of S. pneumoniae.

First report of mixed Trypanosoma cruzi discrete typing units infection in Triatoma phyllosoma in the peri-urban environment of Oaxaca, Mexico

ABSTRACT Background: Chagas disease, a zoonosis transmitted mainly by hematophagous insects of the subfamily Triatominae, is caused by Trypanosoma cruzi, classified into six discrete typing units (DTUs: TcI-TcVI and Tcbat). Methods: Insect vectors were collected from 84 human dwellings in the municipality of Santo Domingo Tehuantepec, Oaxaca, Mexico; 4.76% were infested. DTUs were determined using conventional and nested PCR. Results: The infection rate was 43.6%. All insects were infected with TcI while one specimen showed mixed infection with TcII. Conclusions: This is the first report of T. cruzi mixed infection in Triatoma phyllosoma, its main vector in the study region.

Helicobacter pylori infection factors and immunological typing in community health examination population / 公共卫生与预防医学

Objective To investigate and analyze the risk factors of Helicobacter pylori (Hp) infection and the immunological classification of Hp-infected people in community health examination population. Methods Among of the 2 475 residents in a community who underwent health examination in Guangyuan First People's Hospital were selected between July 2022 and April 2023. Western blotting was used to detect and type the Hp antibodies. The risk factors of Hp infection in the community residents were analyzed by binary logistic regression analysis, and the results of immunological typing were compared among patients with different upper digestive tract diseases and chronic diseases. Results The Hp infection rate among of the 2 475 residents who underwent physical examination was 35.64% (882/2475), and the positive rates of type I Hp antibody and type II Hp antibody were 23.72% (587/2 475) and 11.92% (295/2 475) , respectively. There were significant differences in Hp infection rates in gender, age, smoking history, and whether or not people had diabetes (P<0.05). Multivariate logistic regression analysis showed that male, age ≥60 years old, drinking history and diabetes were risk factors of Hp infection in the community health examination population (P<0.05). The positive rate of type I Hp antibody in men and patients with coronary heart disease was higher than that in women and patients without coronary heart disease (P<0.05). Conclusion The infection rate of Hp among health examination population in this community is low, mainly type I. Hp infection is affected by gender, age, drinking history and diabetes. There are more males in the population with type I Hp antibody positivity, and the risk may be higher in patients with coronary heart disease. Clinically, it is necessary to take susceptible population as the focus of prevention and treatment, and take targeted monitoring and diagnosis and treatment measures.

Hp infection rate, antibody typing and logistics regression analysis of 1111 physical examination people in plateau area / 公共卫生与预防医学

Objective To explore the Helicobacter pylori (Hp) infection rate and antibody typing of 1111 physical examination people in plateau area, and to analyze the risk factors of Hp infection by logistics regression analysis. Methods 1111 healthy people with physical examination in plateau area from January 2022 to December 2022 were selected as the research subjects. The Hp infection rate and antibody typing were calculated, and the risk factors of Hp infection were analyzed by logistics regression analysis. Results The Hp infection rate of physical examination people in plateau area was 62.47% (694/1 111). The infection rate of type I HP in infected patients was higher than that of type Ⅱ HP(75.50% vs 24.50%) (χ2=361.141, P2=4.418, 8.708, 16.565, 32.583, P=0.036, 0.003, 2=5.153, P=0.023). Often eating pickled or barbecued foods [OR (95%CI)=2.038 (1.049-3.961)], history of chronic gastric disease [OR(95%CI)=1.706 (1.132-2.569)] and family members living together≥4 [OR (95%CI)=1.857 (1.135-3.037)] were risk factors of Hp infection, and regular garlic consumption [OR (95%CI)=0.559 (0.346-0.903)] was a protective factor (P=0.036, 0.011, 0.014, 0.018). Conclusion The Hp infection rate and antibody Ure positive rate are higher in physical examination people in plateau area, and chronic gastric disease history and often eating pickled or barbecued foods are risk factors of Hp infection.

Distal tibiofibular syndesmosis fibular notch typing and its clinical significance based on CT / 解剖学报

Objective To investigate the morphological typing and clinical significance of the distal tibiofibular syndesmosis fibular notch based on CT images. Methods According to the inclusion and exclusion ceiteria‚ the imaging data of patients undergoing ankle joint CT examination were analyzed‚ and the inferior tibiofibular joint fibula notch was classified according to the morphological characteristics. The measurements included 8 distances. There were 123 males and 102 females‚ all of whom were Han nationality‚ aged 18-60 years old. Results Retrospectively analyzed the result of 225 patients from December 2013 to December 2022. The distal tibiofibular syndesmosis fibular notch was divided into four types according to morphological characteristics‚ C-shaped (50. 67%)‚ V-shaped (26. 67%)‚ flat-shaped (15. 11%) and L-shaped (7. 56%). The angle between the anterior and posterior facets of the flat shape (145. 56 ± 9. 25)° was the largest and the angle between the anterior and posterior facets of the L shape (125. 07 ± 13. 54)° was the smallest(P< 0. 05); the depth of the notch in the flat shape (3. 11 ± 0. 83) mm was the smallest and in the L shape (4. 47±1. 11) mm was the largest(P<0. 05);The posterior facet length (13. 06 ± 3. 56) mm and anterior tibiofibular gap (3. 83±1. 49) mm on left were larger than on the right side (P<0. 05); The posterior facet length (13. 36 ± 3. 46) mm‚ fibular notch depth (3. 93 ± 1. 10) mm and vertical distance of tibiofibular overlap (9. 10 ± 2. 55) mm larger in men than in women (P<0. 05). Conclusion In this study‚ the data related to the inferior tibiofibular syndesmosis notch were measured and divided into four types according to the shape. The flat inferior tibiofibular syndesmosis notch is more likely to have chronic ankle instability‚ and the fibula is more likely to move forward during anatomical reduction. The inferior tibiofibular syndesmosis of L-shaped and C-shaped notches is more prone to posterior displacement of fibula or poor rotation reduction during anatomical reduction.

Research progress in perioperative management of portal vein thrombosis in liver transplantation / 器官移植

Portal vein thrombosis is one of the common complications of liver cirrhosis. The incidence of portal vein thrombosis is increased with the progression of diseases. The incidence and progression of portal vein thrombosis are associated with multiple factors. The indications of anticoagulant therapy remain to be investigated. At present, portal vein thrombosis is no longer considered as a contraindication for liver transplantation. Nevertheless, complicated portal vein thrombosis will increase perioperative risk of liver transplantation. How to restore the blood flow of portal vein system is a challenge for surgical decision-making in clinical practice. Rational preoperative typing, surgical planning and portal vein reconstruction are the keys to ensure favorable long-term prognosis of liver transplant recipients. In this article, epidemiological status, risk factors, typing and identification of portal vein thrombosis, preoperative and intraoperative management of portal vein thrombosis in liver transplantation, and the impact of portal vein thrombosis on the outcomes of liver transplantation were reviewed, aiming to provide reference for perioperative management of portal vein thrombosis throughout liver transplantation.

New cost-effective human leukocyte antigen testing algorithm for screening of human leukocyte antigen-matched related donor in thalassemia major patient pretransplant workup: A single-center study from resource-constrained settings

Introduction: India has a huge disease burden of thalassemia major with an estimated 40 million carriers and over a million thalassemia major patients. Very few patients are optimally treated, and the standard of care “hematopoietic stem cell transplant” (HSCT) is out of reach for most patients and their families. The cost of HSCT is significant, and a substantial proportion of it goes to human leukocyte antigen (HLA) testing of family members (HLA screening) in hope of getting a matched related donor (MRD) for HSCT. The aim of this study was to establish that a new proposed testing algorithm of HLA typing would be more cost-effective as compared to the conventional HLA screening within MRD families for possible HSCT. Material and Methods: Buccal swab samples of 177 thalassemia patients and their prospective family donors (232) were collected. Using a new HLA testing algorithm, samples were tested for HLA typing in a sequential manner (first HLA-B, then HLA-A, and finally HLA-DR) using the sequence-specific oligonucleotide probe method on the Luminex platform. Results: The new sequential HLA-A, HLA-B, and HLA-DRB1 testing algorithm showed a 49.1% reduction in cost compared to the conventional HLA testing algorithm. Furthermore, 40 patients (22.59%) were found to have HLA-MRD within the family among other samples that were tested. Conclusion: The new HLA testing algorithm proposed in the present study for identifying MRD for HSCT resulted in a substantial reduction in the cost of HSCT workup.

Detection of Trypanosoma cruzi DTUs TcI and TcIV in two outbreaks of orally-transmitted Chagas disease in the Northern region of Brazil

ABSTRACT This study describes the laboratory investigation of two acute Chagas disease outbreaks that occurred in the riverside communities of Marimarituba and Cachoeira do Arua, in the Santarem municipality, Para State, located in the Northern region of Brazil, and occurred in March 2016 and August 2017, respectively. The generation of data regarding the diversity of Trypanosoma cruzi parasites circulating in the Amazon region is key for understanding the emergence and expansion of Chagas disease. This study aimed to identify T. cruzi Discrete Typing Units (DTUs) involved in two outbreaks of acute Chagas disease (ACD) directly from the patient's biological sample. Nested and multiplex PCR targeting the 24Sα (rRNA) and mini-exon genes, respectively, were used to identify T. cruzi DTU in blood samples from patients diagnosed with ACD. The samples with positive cPCR were submitted for analysis for T. cruzi DTUs, which included 13 samples from the patients with ACD by oral transmission and two samples collected from two newborns of two women with ACD, from Marimarituba and Cachoeira do Arua. The samples were classified as T. cruzi TcIV, from Marimarituba's outbreak, and T. cruzi TcI, from Cachoeira do Arua's outbreak. The molecular identification of T. cruzi may increase understanding of the role of this parasite in Chagas disease's emergence within the Amazon region, contributing to the improvement of the management of this important, but also neglected, disease.

Analysis of pathogenic characteristics of enteroaggregative Escherichia coli in children with diarrhea in Shanghai from 2019 to 2021 / 上海预防医学

ObjectiveTo understand the presence of virulence genes， molecular typing characteristics， and antibiotic sensitivity of enteroaggregative Escherichia coli （EAEC） in children with diarrhea in Shanghai， so as to provide a scientific basis for EAEC monitoring and standardized treatment of EAEC infection. MethodsEAEC strains isolated from children （≤5 years old） with diarrhea in six districts of Shanghai were collected as the study subjects. EAEC virulence genes were detected by real-time fluorescence quantitative PCR， molecular typing was performed by pulsed-field gel electrophoresis （PFGE）， and drug susceptibility tests were conducted using the microbroth dilution method. χ2 test and two independent samples t-test were used to compare the differences in virulence genes and antibiotic resistance between suburban and urban EAEC strains. ResultsFrom 2019 to 2021， the overall detection rates of gene aggR， pic and astA of 59 EAEC were 30.5%， 50.8%， and 57.6%， respectively. There was no significant difference in the detection rates of virulence genes between suburban and urban EAEC strains （P>0.05）. PFGE analysis revealed that only two EAEC strains belonged to the same PFGE pattern and were collected from the same hospital， and the overall PFGE patterns were polymorphic. EAEC showed susceptibility to imipenem and colistin E， and the resistance rates to sulfamethoxazole （SXT）， ampicillin （AMP）， nalidixic acid （NAL）， and tetracycline （93.1%， 79.3%， 63.8%， and 58.6%， respectively） were higher than 50.0%. The antibiotic resistance rates of cefazolin （CFZ）， cefotaxime （CTX）， and ciprofloxacin （CIP） were significantly different between EAEC strains from suburban and urban areas （P<0.05）. A total of 47 strains exhibited multi-drug resistance， with the most common resistance spectrum being AMP-SXT-NAL. There was no statistically significant difference in the number of multidrug-resistant EAEC strains between suburban and urban areas （P>0.05）. ConclusionThe EAEC virulence gene assemblages in children with diarrhea in the six districts of Shanghai are diverse， and the molecular typing patterns are relatively scattered， indicating possible cross-infection of homologous strains. Multi-drug resistance in EAEC strains is relatively common， and there is a statistically significant difference in the resistance rates of CFZ， CTX and CIP between urban and suburban EAEC strains. Attention should be given to standardizing the use of clinical antibiotics to effectively control the dissemination of multidrug-resistant EAEC strains.

Antimicrobial resistance and genomic characteristics of Salmonella enterica serovar Derby isolates from clinical patients and food sources in Hangzhou / 中华微生物学和免疫学杂志

Objective:To analyze the antimicrobial resistance and genomic characteristics of Salmonella enterica serovar Derby strains isolated from human and food sources in Hangzhou. Methods:A total of 60 Salmonella enterica serovar Derby strains isolated in Hangzhou during the period from 2015 to 2020 were subjected to antimicrobial susceptibility testing, pulsed field gel electrophoresis (PFGE) typing and whole-genome sequencing. Multilocus sequence typing (MLST), core genome multilocus sequence typing (cgMLST) and the identification of antimicrobial resistance genes were performed using the sequencing data. Phylogenetic tree based on the single nucleotide polymorphism (SNP) sites in the 60 genomes from Hangzhou and 379 genomes from public databases was constructed. Results:No significant difference was observed in the drug resistance rates between the clinical strains and food strains in Hangzhou. The multidrug resistance (MDR) rate was 76.7% (46/60). All of the 60 Salmonella Derby strains were positive for the antimicrobial resistance genes aac(6′)- Iaa and fosA7. The 60 strains were subtyped into 46 molecular types by PFGE and 53 molecular types by cgMLST(HC2). Except for one strain belonging to ST3220, the other Salmonella Derby strains were ST40. The phylogenetic analysis showed that some strains isolated in Hangzhou were close to the strains in Southeast Asia, suggesting the possibility of cross-border transmission of ST40 strains, with the main food sources being pork and fish; other strains were close to those circulating in Beijing, Guangzhou, Hubei, Chongqing and other provinces, suggesting the possibility of cross-province transmission of the strains, with the main food sources being pork, beef and chicken. Conclusions:The epidemic of Salmonella Derby in Hangzhou was mainly caused by the spread of ST40 strains and MDR was common. Clinical infections might be closely related to the consumption of pork, beef, chicken and fish. There was the possibility of cross-border transmission of Salmonella Derby between Hangzhou and Southeast Asia and cross-province transmission in China.

Qualitative characteristics of contrast-enhanced ultrasound and VueBox quantitative perfusion analysis of the molecular classification of breast cancer / 中华超声影像学杂志

Objective:To investigate the value of qualitative characteristics of contrast-enhanced ultrasound (CEUS) and VueBox quantitative parameters in the evaluation of pathological molecular typing of breast cancer.Methods:A retrospective analysis was performed on 133 patients with pathologically confirmed breast cancer who underwent CEUS examination in the People′s Hospital of Guangxi Zhuang Autonomous Region from January 2020 to July 2022. The patients were divided into Luminal A type, Luminal B type, human epidermal growth factor receptor-2(HER-2) type and triple negative type according to the results of immunohistochemistry. The differences of qualitative characteristics and quantitative parameters of CEUS in different molecular subtypes of breast cancer were analyzed. The ROC curve was used to evaluate the diagnostic efficacy of CEUS in the differentiation of molecular subtypes of breast cancer.Results:There were significant differences in enhancement intensity, post-enhancement boundary, filling defect and peripheral radial convergence among different molecular subtypes of breast cancer(all P<0.05), while there was no significant difference in enhancement uniformity ( P>0.05). Peak enhancement (PE), wash-in and wash-out areas under the curve (WiWoAUC), and wash-in ratio (WiR) of HER-2 type and triple-negative type breast cancer were higher than Luminal A type and Luminal B type (all P<0.05). ROC curve analysis showed that PE and radial convergence had reasonable diagnostic efficiency in Luminal A type, and the areas under the curve were 0.849 and 0.780, sensitivity was 0.711 and 0.889, specificity was 0.909 and 0.671, accuracy was 0.842 and 0.744, respectively. The areas under the curve of PE in diagnosing Luminal B type was 0.852, the sensitivity, specificity, and accuracy were 0.825, 0.763 and 0.782, respectively. The area under the curve of WiWoAUC and filling defect in diagnosing HER-2 type were 0.912 and 0.898, the sensitivity was 0.903 and 0.903, the specificity was 0.853 and 0.892, and the accuracy was 0.865 and 0.895, respectively. The area under the curve of clear boundary after enhancement in diagnosing triple negative type was 0.919, and the sensitivity, specificity and accuracy were 0.941, 0.897 and 0.902, respectively. Conclusions:There are differences in the qualitative characteristics and quantitative parameters of contrast-enhanced ultrasound in different molecular types of breast cancer. CEUS is suggested as a noninvasive modality for preoperative prediction of molecular subtypes of breast cancer.

Analysis of the influencing factors of urinary tract infection in pregnant women with diabetes and the distribution characteristics of pathogens in the middle urinary tract / 中国医师杂志

Objective:To investigate the influencing factors of urinary tract infection in pregnant women with diabetes and the distribution characteristics of pathogens in the middle urinary tract.Methods:A total of 220 patients with gestational diabetes who visited the Second People′s Hospital of Lianyungang City from December 2018 to December 2021 were selected as the study subjects, and the incidence of urinary tract infection was counted. According to the diagnosis results of urinary tract infection, they were divided into infected group and uninfected group. The infected group took the middle urine for pathogen culture, and the resistance rate of main gram-negative bacteria to antibiotics was analyzed; Logistic regression model was used to analyze the influencing factors of urinary tract infection in pregnant women with diabetes.Results:There were 32 cases of urinary tract infection in 220 patients with gestational diabetes, and the infection rate was 14.55%(32/220). 43 strains of pathogenic bacteria were identified, mainly gram-negative bacilli [72.09%(31/43)], followed by gram-positive cocci [20.93%(9/43)] and fungi [6.98%(3/43)]. Amongthe main gram-negative bacteria, escherichia coli had a high resistance rate to ampicillin and levofloxacin, while Klebsiella pneumoniae had a high resistance rate to ampicillin and cefazolin; There were significant differences between the infected group and the non infected group in age, hospital stay, personal urinary tract infection history, pregnancy sexual life history, use of antibiotics, fasting blood sugar, serum albumin, and glycated hemoglobin (all P<0.05); Multivariate logistic regression results showed that personal history of urinary tract infection, sexual life during pregnancy, non-standard use of antibiotics, serum albumin<30 g/L, glycated hemoglobin ≥7%, and fasting blood sugar ≥8.5 mmol/L were independent risk factors for urinary tract infection in pregnant diabetes patients (all P<0.05). Conclusions:There is a high incidence of urinary tract infection in patients with gestational diabetes, and the risk factors are complex. Gram negative bacilli are the main pathogenic bacteria. Antibacterial drugs can be reasonably selected for intervention according to drug sensitivity test in clinical practice.

Genetic variation characteristics of HA gene of influenza A virus (H3N2) in Guizhou province from 2017 to 2019 / 中国基层医药

Objective:To analyze the genetic variation characteristics of the HA gene of influenza A virus (H3N2) in Guizhou province from 2017 to 2019. Methods:Twenty strains of influenza A virus (H3N2) were randomly selected from 10 network laboratories in Guizhou province for RNA extraction. Reverse transcriptase-polymerase chain reaction and sequencing were performed. The products were analyzed using bioinformatics software.Results:The nucleotide homology of the HA gene of the 20 strains was 97.7%-100%, which was highly homologous to the vaccine strains A/Hong-Kong/4801/2014 recommended by WHO in 2017 and A/Singapore-INFIMH/16-0019/2016 recommended by WHO in 2018, but they were significantly different from the vaccine strain A/Kansas/14/2017 recommended by WHO in 2019. Genetic analysis showed that the 20 strains were divided into two branches, and the strains that were prevalent in 2019 were located in different branches, with marked genetic differences. Key site analysis showed mutations in antigenic determinants A, B, C, and E and mutations in the anterior and posterior walls of receptor binding sites. Key site analysis also showed that there was an increase in the number of glycosylation sites compared with the vaccine strains prevalent in the same year. Genetic distance, antigen sites, and glycosylation sites were slightly different between virus strains prevalent in 2017-2018 and virus strains prevalent in 2019. Conclusion:The HA gene of the influenza A virus subtype H3N2 in Guizhou province from 2017 to 2019 showed heterogeneity and gene mutation, especially in 2019. Therefore, close monitoring of the genetic evolution of the influenza A virus subtype H3N2 is necessary.

Genetic characteristics of multi-locus sequence typing of Brucella isolates in Guizhou Province from 2017 to 2021 / 中华地方病学杂志

Objective:To study the multi-locus sequence typing (MLST) gene characteristics of Brucella isolates in Guizhou Province. Methods:Brucella strains, which were isolated from 2017 to 2021 in Guizhou Province (preserved in the Bacterial and Viral Seed Bank of Guizhou Center for Disease Control and Prevention) were identified Brucella and species/types by BCSP31-PCR and AMOS-PCR methods, respectively. MLST method was used for genotyping, and Biometrics 8.0 software was used for cluster analysis of the typing results. Results:A total of 32 strains of Brucella were isolated in Guizhou Province and identified as Brucella melitensis ( B.melitensis) by BCSP31-PCR and AMOS-PCR methods. These strains were classified into 2 ST types (ST8 and ST39) by MLST method, with 28 strains of ST8 type(87.5%) and 4 strains of ST39 type (12.5%). The 28 strains of ST8 type were distributed in 7 cities (prefectures) of Guizhou Province, while the 4 strains of ST39 type were only found in Qianxinan Buyi and Miao Autonomous Prefecture. The cluster analysis results showed that ST8 and ST39 types strains were clustered in a group with the reference strain of B.melitensis, and there was only one nucleotide site difference between ST39 and ST8 types in the glk gene, indicating a close genetic relationship. Conclusions:B.melitensis is the main pathogen of the brucellosis epidemic in Guizhou Province in recent years. ST8 is the dominant MLST genotype in Guizhou Province.

Genotyping and traceability analysis of Brucella isolated from Himalayan marmot in Qinghai-Tibet Plateau by MLVA / 中华地方病学杂志

Objective:To observe multiple locus variable-number tandem repeat analysis (MLVA) typing of Brucella isolated from Himalayan marmot in Qinghai-Tibet Plateau of Qinghai Province, and to explore the relationship between the strains and strains previous isolated from Qinghai Province. Methods:Blood samples of Himalayan marmot were collected in Qinghai-Tibet Plateau of Qinghai Province from March 2019 to October 2020. Pathogens were isolated and cultured from Brucella antibody positive samples identified by using the rose bengal test (RBT). Conventional biological methods and molecular biological methods (BCSP31-PCR and AMOS-PCR) were used for strain identification. At the same time, MLVA method was used to genotype the isolated strains, and cluster analysis was used to analyze the genetic relationships between the strains based on the genotype of 70 Brucella isolated from different hosts in Qinghai Province. Results:A total of 1 466 blood samples of Himalayan marmot were collected from Qinghai-Tibet Plateau. Two strains of Brucella were isolated and cultured from 64 RBT-positive samples, named QH2013054 and QH2013062, respectively. They were identified as Brucella ovis biotype Ⅲ by conventional and molecular biological methods. The MLVA genotyping results showed that QH2013054 and QH2013062 were different at the Bru16 locus, indicating different MLVA genotypes. Cluster analysis showed that strain QH2013054 had the same MLVA genotype as 7 strains, among which 6 strains were from 3 farmers and 3 sheep from the same family in Gonghe County, and 1 strain was from a farmer in Menyuan Hui Autonomous County. The strain QH2013062 had the same MLVA genotype as 4 strains, including 3 strains from 3 farmers in Menyuan Hui Autonomous County and 1 strain from a farmer in Tu Autonomous County of Huzhu. Conclusions:The strains of Brucella isolated from Himalayan marmot in Qinghai-Tibet Plateau of Qinghai Province have the same MLVA genotype as some strains of Brucella isolated from humans and sheep in Qinghai Province. It is speculated that the host humans, sheep and Himalayan marmot in Qinghai-Tibet Plateau may have a common source of infection.

Multi-locus sequence typing of human Brucella isolated in Sichuan Province from 2014 to 2020 / 中华地方病学杂志

Objective:To learn about the genotyping of human Brucella isolated from Sichuan Province. Methods:BCSP31-PCR and AMOS-PCR were used to identify the genus and biotype of the 66 strains isolated from confirmed human brucellosis cases in Sichuan Province from 2014 to 2020, respectively. The isolated strains were genotyped by multi-locus sequence typing (MLST)-9. The sequence type (ST) was compared trough the online MLST database. A minimum spanning tree (MST) was constructed to cluster the newly discovered and known ST using the BioNumerics software version 7.6.Results:The 66 strains isolated from human cases of brucellosis in Sichuan Province from 2014 to 2020 were Brucella, and 65 of them were Brucella melitensis while one strain was Brucella abortus. The MLST method identified three known STs (ST-8, ST-39 and ST-2) and one newly type (ST-101). Among them, ST-8 was the main ST in Sichuan Province (90.91%, 60/66), another 4 strains of Brucella melitensis were ST-39, and 1 strain of Brucella abortus was ST-2. The newly type ST-101 was isolated from Leshan City in 2019, belonging to the Brucella melitensis and closely related to the evolution of ST-8. Conclusion:Brucella melitensis is the main epidemic Brucella strain in Sichuan Province, ST-8 is predominant genotype, with a small amount of ST-39, ST-101 and ST-2.

Multilocus sequence typing, clinical characteristic, and drug resistance of Salmonella typhimurium in 93 children / 中华实用儿科临床杂志

Objective:To investigate the multilocus sequence typing (MLST), clinical manifestations, and drug resistance of Salmonella typhimurium in children, thus providing references for the diagnosis, treatment, and prevention of pediatric Salmonella typhimurium infection.Methods:The clinical data of patients with Salmonella typhimurium serotypes confirmed by stool or blood culture between November 2017 and October 2020 were retrospectively collected from Fujian Maternity and Child Health Hospital.MSLT and drug susceptibility test were performed on Salmonella typhimurium isolated from the samples. Kruskal- Wallis test, Chi- square test, and Fisher′ s exact probability method were employed for data analyses. Results:Salmonella typhimurium was cultured from clinical samples of 96 children, of which, 93 samples were effective, including 92 stool samples and 1 blood sample from 53 boys(56.99%) and 40 girls(43.01%). The median age of disease onset occurred at 12.0 (8.5-22.0) months, with peak months of onset ranging from July to October.According to MLST classification, 93 children were divided into ST34 classification( n=58), ST19 classification( n=22) and other classification( n=13). Respiratory symptoms were significant different among MLST classification, and ST34 type Salmonella typhimurium enteritis was more commonly accompanied by respiratory symptoms ( χ2=17.657, P<0.001; Cramer V=0.421, P<0.001). There were significant differences in the drug sensitivity to Ampicillin ( χ2=8.774, P=0.033), Piperacillin tazobactam ( χ2=6.713, P=0.022), Ciprofloxacin ( χ2=20.780, P<0.001), Sulfamethoxazole ( χ2=15.364, P=0.001), Ampicillin sulbactam ( χ2=17.626, P=0.001) and Levofloxacin ( χ2=25.648, P<0.001) among 3 groups.No significant difference was found in the sensitivity to Ceftriaxone ( χ2=1.027, P=0.621), Ceftazidime ( χ2=7.637, P=0.059), Cefepime ( χ2=6.099, P=0.116) and Cefoperazone/Sulbactam ( χ2=2.405, P=0.649). All MLST types were sensitive to Imipenem and Meropenem. Conclusions:Salmonella typhimurium infection mainly affects infants, with the peak months of onset ranging from July to October.MLST34 is the main serotype, accompanied respiratory symptoms.Antibiotics should be selected according to drug sensitivity, and third-generation cephalosporins can be selected empirically without drug susceptibility test results.

Progress of gene alterations and molecular typing of peripheral T-cell lymphoma / 白血病·淋巴瘤

Peripheral T-cell lymphoma (PTCL) is a group of heterogeneous malignant tumors with poor prognosis, with a lack of standard treatment regimen and poor efficacy of traditional chemotherapy. Therefore, finding new and more effective therapeutic targets to improve the efficacy of PTCL is an urgent clinical problem. In recent years, as the exploration of PTCL at the genetic and molecular levels has intensified, novel therapeutic targets based on gene alterations and molecular typing have been identified. This article summarizes the research progress of main gene alterations and molecular typing of PTCL in recent years.

Study on the progress of HIV typing methods / 上海预防医学

As a retrovirus with high recombination and mutation rate， HIV targets CD4+ T lymphocytes， causing damage to the body's immune system and eventually leading to severe immune function defects. Different subtypes of the HIV virus exhibit significant sequence differences in their structural and regulatory genes， and this diversity is closely related to etiology， transmission， diagnosis， drug therapy， disease progression， and vaccine development. As a country with the largest number of HIV subtypes， rapid and accurate typing of the HIV virus holds great significance for China's efforts in disease prevention and control. This study provides a comprehensive reveiw of domestic and international HIV genotyping methods， and summarizes the clinical significance of different subtypes in order to provide reference for further research.

Research on the contamination, drug resistance and molecular typing of Vibrio parahaemolyticus isolated from aquatic products in Nanchang City market / 中国热带医学

@#Abstract: Objective　To understand the contamination status, drug resistance, virulence gene carrying status, and molecular typing characteristics of Vibrio parahaemolyticus (VP) in aquatic products sold in Nanchang City. Methods　A total of 170 commercial crayfishes, freshwater fish frogs and related smears samples were collected from various farmers' markets in Nanchang from March to September 2021. The strains of V. parahaemolyticus were detected and isolated from the samples. Antibiotic resistance test, virulence gene test, and pulsed-field gel electrophoresis (PFGE) molecular typing analysis were carried out. Results　Among the collected samples, V.parahaemolyticus was only isolated from crayfish and crayfish smear samples, with a total of 35 strains of VP isolated. No V.parahaemolyticus strain was isolated from other freshwater fish, frogs, and their smear samples. Among the 17 common antibiotics tested, only two trains showed resistance to ampicillin, and one strain to streptomycin, , and all were sensitive to other antibiotics; all 35 strains of V. parahaemolyticus carried the gene, but only one strain carried the heat-resistant related hemolysin gene trh, and no direct heat-resistant hemolysin gene tdh positive strain was found; PFGE pattern clustering showed that there was no strain with the same PFGE pattern, and there was no obvious dominant cluster among these strains, and their genetic relationship was relatively distant. Conclusions　The contamination of V. parahaemolyticus in small and medium-sized crayfish sold in the market in Nanchang City is relatively serious. The V. parahaemolyticus isolates in these polluted crayfish generally do not carry key virulence genes such as tdh, are sensitive to common antibiotics, and only have low-level resistance to ampicillin and streptomycin. PFGE pattern clustering showed that V. parahaemolyticus does not have no obvious dominant cluster, and these strains have rich genetic diversity, indicating that they may have different sources.