ObjectiveTo conduct an epidemiological investigation, isolate and identify the pathogenic bacteria, and perform whole-genome sequencing (WGS) analysis of a food poisoning outbreak in Suzhou High-tech Zone, so as to provide references for the prevention and management of similar incidents. MethodsAn epidemiological investigation was carried out on affected individuals and restaurant staff. Multi-pathogen screening was performed on rectal swab samples from affected cases and restaurant staff, as well as on environmental swab samples from food preparation areas and retained food samples. WGS was performed on the pathogens isolated from the samples. ResultsA total of 15 cases were identified through hospital visit record reviews and on-site inquiries. Of the 15 case samples, 14 tested positive for Staphylococcus aureus (SA). In addition, 3 out of 15 staff samples and 6 out of 34 retained food samples tested positive for SA. WGS results revealed that the 6 food-derived isolates and 13 case-derived isolates shared the same sequence type (ST), Staphylococcal Protein A (SPA) type, and enterotoxin gene profile, with whole-genome single nucleotide polymorphism (wgSNP) differences of ≤5. Two novel SA sequence types: ST9159 and ST9161, were also identified in this study. ConclusionThis food poisoning outbreak is caused by contamination food with SA harbouring the seb and sec enterotoxin genes. The primary causes of contamination and cross-contamination included improper food handling practices, the use of the same utensils for raw and cooked foods, and extended storage of certain dishes at room temperature. Strengthening sanitary supervision in food handling facilities is crucial for reducing the occurrence of similar incidents.

【Objective】 To analyze the association between the composition of gut microbiota and blood pressure in children aged 6 - 9 years, in order to provide new ideas for childhood hypertension prevention and treatment. 【Methods】 A total of 411 children aged 6 - 9 years were recruited in Guangzhou from December 2015 to March 2017. The gut microbiota was characterized by 16S ribosomal RNA amplicon sequencing. The multivariate methods with unbiased variable selection in R (MUVR) were performed to identify the significant OTUs. Spearman correlation as well as multiple linear regression were used to explore the relationship between gut microbiota and blood pressure in children. 【Results】 Significant difference in β diversity index was observed between children with normal blood pressure and those with abnormal blood pressure (R²weighted=0.015,Pweighted=0.01; R²unweighted=0.027, Punweighted=0.001). After adjustment for covariates and controlling the false discovery rate (FDR), multiple linear regression analysis showed that blood pressure level in children decreased with the increasing abundance of OTU_3 (genus Blautia), OTU_131 (genus [Clostridium]_innocuum_group), OTU_1776 (genus Blautia), OTU_2159 (genus Prevotella) and OTU_91 (species Bifidobacterium_breve) (β:-0.18 --0.14; PFDR<0.05. In contrast, blood pressure in children increased with the increasing abundance of OTU_108(genus Sutterella), OTU_1(species Faecalibacterium_prausnitzii)、OTU_8(genus Roseburia), OTU_48 (genus Lachnoclostridium), OTU_81 (genus Coprococcus), OTU_401 (family Lachnospiraceae), OTU_1284 (family Lachnospiraceae) and OTU_2793 (family Lachnospiraceae)(β: 0.14 - 0.21; PFDR<0.05. The influence of gut microbiota on systolic pressure and diastolic pressure may be mediated by the increase of body mass index (BMI). 【Conclusions】 Pediatric blood pressure level is associated with the composition of gut microbiota, while BMI partially plays a mediating role in the relationship. It is recommended to modulate the abundance of microbiota as genus Blautia, Sutterella and so on to prevent hypertension in children.

Objective To understand the infection status of patients with maintenance hemodialysis(MHD)in Guizhou Province,and provide basis for the prevention and control of hemodialysis-related infection.Methods MHD patients in hemodialysis centers of 124 secondary and or higher grade medical institutions in Guizhou Province from July to December 2022 were surveyed.Survey content included the general conditions of patients,hemodialysis-related conditions,infection of pathogens of blood-borne diseases,and other infection-related conditions.Results A total of 15 114 MHD patients were surveyed,with age mainly ranging from 36 to＜60 years old(55.83％).Hemodialysis history ranged mainly from 1 year to＜5 years(59.37％),and the frequency of hemodi-alysis was mainly 3 times per week(73.91％).Autologous arteriovenous fistula(AVF)was the major vascular access for dialysis,with a total of 12 948 cases(85.77％).The main primary disease was chronic renal failure(99.89％).The infection rates of hepatitis B virus(HBV),hepatitis C virus(HCV),human immunodeficiency vi-rus(HIV),and Treponema pallidum in MHD patients were 5.29％,0.64％,0.24％,and 1.70％,respectively.HBV infection rates among MHD patients of different ages,different numbers of dialysis hospitals,and dialysis in-stitutions of different scales showed statistically significant differences(all P＜0.05).HCV infection rates among MHD patients of different ages,with different dialysis times and from institutions of different scales were signifi-cantly different(all P＜0.05).TP infection rates among MHD patients of different ages and different numbers of dialysis hospitals were all significantly different(all P＜0.05).Infection rates of HBV and HCV in MHD patients aged from 36 to 60 years old(not included)were relatively higher(6.10％and 0.84％,respectively).Patients with dialysis time ≥10 years had a higher HCV infection rate(1.64％).Infection rates of HCV,HIV,and TP in pa-tients dialyzed in medical institutions with ≥90 dialysis beds were relatively higher(0.74％,0.28％,and 1.94％,respectively).Medical institutions with＜30 dialysis beds had the highest HBV infection rate(18.64％).There were 9 cases(0.06％)of vascular puncture infection,12 cases(0.08％)of bloodstream infection,7 cases(0.05％)of vascular access-related bloodstream infection,and 30 cases(0.20％)of pulmonary infection.Vascular access-re-lated bloodstream infection rate and pulmonary infection rate among MHD patients with different types of vascular access showed statistically significant difference(all P＜0.05).Vascular access-related bloodstream infection rate(0.37％)and pulmonary infection rate(1.10％)of patients with non-cuffed catheters vascular access were higher than those of other types.Conclusion MHD patients in Guizhou Province are mainly middle-aged and young peo-ple,with more males than females.The dialysis frequency is mostly 3 times per week,and AVF is the major vascu-lar access.MHD patients are prone to complications such as infections of HBV,HCV,HIV,and TP,as well as bloodstream infection and pulmonary infection.

Objective To conduct risk assessment analysis through risk assessment model for postoperative pneu-monia(POP)in surgical departments constructed according to analytic hierarchy process(AHP)-risk matrix,and evaluate the application effectiveness of the model.Methods Taking a tertiary comprehensive teaching hospital as an example,a risk assessment was conducted on the occurrence of POP in 15 surgical departments in 2022.The ap-plication effect of POP risk assessment model for the surgical departments constructed based on the AHP-risk ma-trix was evaluated,and the POP risk level of the surgical departments was determined.Results Through applica-tion of risk assessment model,the POP risk level of the surgical departments was divided into 5 levels,namely ex-tremely high risk(n=3),high risk(n=1),medium risk(n=5),low risk(n=4),and extremely low risk(n=2).Conclusion The application effect of the surgical POP risk assessment model based on AHP-risk matrix method is good,achieving quantitative assessment of healthcare-associated infection risk,and providing data basis and support for further targeted risk control.

Objective To investigate a suspected outbreak of carbapenem-resistant Klebsiella pneumoniae(CRKP)healthcare-associated bloodstream infection(HA-BSI),provide reference for effective control of CRKP in-fection.Methods The characteristics of CRKP infected patients and the risk factors for the event transmission in an adult hematology department of a teaching hospital in June 2022 were obtained by field epidemiological investigation.The specimens of environmental target strains were co-llected by blood nutrient agar inoculation,the removal status of environmental microorganisms and the effect of infection control after implementing control measures were com-pared.Results There were a total of 6 cases of CRKP HA-BSI,with an attacking rate of 1.29％(6/464),which was significantly higher than 0 during the same period in 2021,and difference was statistically significant(P=0.011).In environmental hygiene monitoring,the detection rate of CRKP was 2.27％(1/44),which was from the surface of bed curtain in the living unit of infected patients,homology analysis with CRKP detected from 2 patients revealed that the 16s RNA of 3 CRKP strains was completely identical,with a similarity of 100％.Seven house-keeping genes of 3 CRKP strains were all identical and belonged to the ST11 type.Comprehensive control measures were taken:appropriate closure of the ward,centralized isolation of patients,terminal disinfection of the ward,reg-ular health care workers and relative restriction of their activity areas.After the measures were taken,the qualified rate of microbial colony count in the ward increased compared to before taking the measures(2.27％vs 68.89％,P＜0.001),with a statistically significant difference,there were no more CRKP infected cases after the intervention,indicating that the control measures were effective.Conclusion This outbreak was caused by ST11 type of common CRKP in China,and laminar bed curtains are carriers of pathogen transmission.It is speculated that non-standard cleaning and disinfection,as well as inadequate implementation of hand hygiene are the main causes for transmis-sion.Adopting an appropriate strategy of closing the ward and concentrating patient isolation can quickly and effec-tively prevent the transmission of the event.

Objective To study the possibility of using cone-beam computed tomography(CBCT)with CTAn software to analyze bone resistance during mandibular third molar extraction surgery.Methods Fifty-three patients who underwent CBCT scans for third molars at the Department of Stomatology from January 1st 2021 to July 31th 2023 were induded,involving a total of 91 mandibular third mo-lars.CTAn software was used to analyze the buccal and lingual bone volume regions around mandibular third molars in CBCT images,assessing three-dimensional bone microstructural parameters.Results Significant differences(P＜0.05)in tissue volume,trabecular bone volume/tissue volume,bone surface/trabecular bone volume,bone surface/tissue volume,and bone mineral density between the buccal and lingual bone volume areas were observed in both the total sample and in stratified analyses based on themesially inclined/verticalmandibular third molar impactionand gender.In high/mid-level mesially inclined and vertical impactions,females showed more significant differences in microstructural parameters of the buccal and lingual bone volume compared to males.Conclusion The inte-gration of CBCT with CTAn software offers a viable method for assessing bone resistance during mandibular third molar extractions.Lin-gual bone exhibits greater bone tissue content,denser trabeculae with smaller tissue volume compared to buccal bone.During mandibu-lar third molar extraction,compressing the buccal alveolar bone helps create trabecular compression space more easily.Additionally,the buccal alveolar bone is more amenable to grinding than the lingual side,thereby achieving a reasonable buccal dislocation of root.For female patients with high/mid-level mesially inclined and vertical impactions of the mandibular third molars,a buccal approach is more advisable to be followed.The evaluation of bone microstructural parameters and accurate determination of bone resistance offer valuable insights for the minimally invasive removal of impacted teeth.

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.

Objective:To investigate the role of dendritic cells (DC) in Chlamydia muridarum ( Cm) respiratory infection and their effect on adaptive immune response. Methods:C57BL/6 mice were exposed to 1×10 3 inclusion-forming units (IFU) of Cm through inhalation to establish the mouse model of Cm respiratory infection. The proportion of CD11c + MHCⅡ + DC and the expression of costimulatory molecules (CD40, CD80 and CD86) in spleen tissues were detected by flow cytometry on 0, 3 and 7 d after infection. The expression of IL-12p40, IL-10 and IL-6 at mRNA level in spleen tissues was detected by qPCR. Mouse splenic DC isolated on 7 d after Cm infection were sorted by magnetic beads and then transferred to recipient mice. Th1 response in the recipient mice was measured using intracellular cytokine staining 14 d after infection. Results:Cm respiratory infection induced massive infiltration of DC and promoted the expression of costimulatory molecules on splenic DC. The expression of IL-12 and IL-10 at mRNA level in splenic DC reached the peak on 3 d after infection. Transferring the splenic DC of Cm-infected mice into the recipient mice could alleviate the disease condition in the recipient mice after Cm infection with reduced Cm inclusion-forming units in lung tissues and significantly increased proportion of Th1 cells in lung and spleen tissues. Conclusions:Cm respiratory infection could induce the maturation and activation of DC, which promoted Th1 immune response. DC played an important role in Cm infection.

Objective:To compare the efficacy of intraluminal microwave ablation with radiofrequency ablation in the treatment of varicose veins of the lower extremities.Methods:The clinical data of 520 patients (522 affected limbs) who underwent lower extremity varicose vein surgery at the Department of Vascular Surgery of the First Affiliated Hospital of Anhui Medical University from Jun 2021 to Sep 2022 were collected. Patients were divided into endovenous microwave ablation group (EMWA group, n = 201) and radiofrequency ablation group (RFA group, n = 321). Follow-up was performed at 1 week, 1 , 6 and 12 months after surgery. The primary efficacy endpoint was the occlusion rate of the treated segment vein, the primary safety endpoint was the incidence of surgery-related and/or device-related complications, and the secondary endpoints were the venous clinical severity score (VCSS) and chronic venous insufficiency quality of life questionnaire (CIVIQ) scores at follow-up. Results:The technique success rate and the occlusion rate of the affected segment vein was 100% in both groups evaluated one week after surgery; Six and 12 months after surgery, the occlusion rate in the RFA group was 98.9%, and that in the EMWA group was 99.3% and respectively 97.8%, 97.2% ,without statically significant difference.During the follow-up period, there were no cases of reoperation due to vein recanalization. no serious events such as deep vein thrombosis, pulmonary embolism or death occurred in either group. The incidence of adverse events (induration, ecchymosis, skin burn, incision infection, limb numbness, hematoma, thrombotic superficial phlebitis, endovenous heat induced thrombosis, etc.) in both groups was compared, and the difference was not statistically significant. VCSS and CIVIQ scores improved significantly in both groups at 1 ,6 and 12 months after treatment, and the difference was statistically significant(all P < 0.01). Conclusion:EMWA and RFA have the advantages of simple operation, good clinical efficacy and high degree of improvement in quality of life.

Objective:To investigate the role of IL-21/IL-21R-mediated CD4 + T cells in Chlamydia muridarum ( Cm) respiratory infection. Methods:C57BL/6 mice (WT mice) and IL-21R -/- mice were used to establish the models of Cm respiratory infection through intranasal inhalation of Cm. Flow cytometry was used to detect the proportion, number, activity and function of CD4 + T cells in lung and spleen tissues at 0, 3, 7 and 14 d after Cm respiratory tract infection. IFN-γ and IL-4 levels in spleen cell culture supernatants were detected by ELISA. Na?ve WT mice were transferred with CD4 + T cells in the spleen tissues of IL-21R -/- mice or WT mice on 7 d after infection and given Cm intranasally 2 h later. Then the mice were weighed daily and sacrificed on 14 d after infection. The bacterial load and pathological changes in lung were analyzed. Flow cytometry was performed to detect the proportions and numbers of neutrophils (CD45 + CD11b + Gr-1 high) and alveolar macrophages (CD45 + F4/80 + CD11c high)as well as the proportions of Th1 (IFN-γ + CD4 + ) and Th2 (IL-4 + CD4 + ) cells. ELISA was also performed to measure IFN-γ and IL-4 levels in spleen cell culture supernatants. Results:Compared with WT mice, IL-21R -/- mice showed elevated numbers and enhanced activation of CD4 + T cells, increased proportion of Th1 cells and decreased proportion of Th2 cells in spleen and lung tissues after Cm respiratory infection. Besides, IFN-γ levels increased, while IL-4 levels decreased in spleen cell culture supernatants of IL-21R -/- mice. After Cm infection, the na?ve WT transferred with CD4 + T cells from IL-21R -/- mice showed less body weight loss, reduced bacterial load and alleviated pathological changes in lung tissues, increased proportion of Th1 cells in lung tissue and higher IFN-γ level in spleen cell culture supernatants. Conclusions:IL-21/IL-21R-mediated CD4 + T cells could aggravate Cm respiratory infection by suppressing Th1 cell immune responses.