BACKGROUND:The key to preventing the recurrence of intrauterine adhesions is to reconstruct the endometrium with normal function.The latest breakthrough in the treatment of recurrent intrauterine adhesions in and outside China is the use of degradable materials to prepare hydrogels to prevent the recurrence of adhesions. OBJECTIVE:To review the research advance in hydrogel-promoted endometrial repair in intrauterine adhesions. METHODS:PubMed,Web of Science,China National Knowledge Infrastructure(CNKI),and WanFang databases were searched systematically,with the keywords"intrauterine adhesions,endometrial injury,endometrium regeneration,hydrogel"in Chinese and English.Relevant articles published in each database from January 1990 to March 2023 were collected. RESULTS AND CONCLUSION:In recent years,research on hydrogel-promoted endometrial repair in uterine adhesions in and outside China has made some progress and plays an important role in the prevention and treatment of intrauterine adhesions and the promotion of endometrial repair:(1)As an important carrier in tissue engineering,hydrogel itself has excellent biocompatibility,biodegradability and three-dimensional network structure,which can be better applied in the treatment of intrauterine adhesions.(2)The hydrogel-based carrier system can promote the proliferation and differentiation of endometrial epithelial cells by transporting drugs/biologics/stem cells,and restore normal uterine morphology to prevent adhesion recurrence.(3)Hyaluronic acid hydrogels can not only meet good biocompatibility,but also promote the proliferation and differentiation of endometrial epithelial cells,and will be hydrolyzed by corresponding enzymes in utero,without affecting the normal metabolism of the body.They are currently commonly used uterine anti-adhesion agents in the clinic and are also the most commonly used hydrogel carriers in tissue engineering research.(4)Poloxamer hydrogel with excellent temperature-sensitive properties can rapidly gelate into the body,quickly form a physical barrier,and can play a slow-release effect on carrying substances and provide a platform for cell growth/adhesion.(5)There are broad prospects for the preparation of therapeutic hydrogels using materials with different characteristics,such as temperature-sensitive hydrogels,pH-responsive hydrogels and photosensitive hydrogels,but there are still many problems to be solved,such as the safety of the hydrogel system,whether the degradation products cause immune reactions,and whether they have an impact on the normal body's menstrual period.A large number of animal experiments and clinical trials are needed to verify its safety and efficacy,and continuously improve the treatment strategy.

Objective:To investigate the association of urinary cadmium level with body mass index (BMI) and body circumferences among the older adults over 65 years old in 9 longevity areas of China.Methods:Subjects were older adults over 65 years old from the Healthy Aging and Biomarkers Cohort Study (HABCS) between 2017 and 2018 conducted in 9 longevity areas in China. A total of 1 968 older adults were included in this study. Information including socio-demographic characteristics, lifestyles, diet intake, and health status was collected by using questionnaires and physical examinations. Urine samples were collected to detect urinary cadmium and creatinine levels. Body circumferences included waist circumference, hip circumference and calf circumference. Subjects were divided into three groups (low:<0.77 μg/g·creatinine, middle:0.77-1.69 μg/g·creatinine, high:≥1.69 μg/g·creatinine) by tertiles of creatinine-adjusted urinary cadmium concentration. Multiple linear regression models were used to analyze the association of creatinine-adjusted urinary cadmium level with BMI and body circumferences. The dose-response relationship of creatinine-adjusted urinary cadmium concentration with BMI and body circumferences was analyzed by using restrictive cubic splines fitting multiple linear regression model.Results:The mean age of subjects was (83.34±11.14) years old. The median (Q1, Q3) concentration of creatinine-adjusted urinary cadmium was 1.13 (0.63, 2.09) μg/g·creatinine, and the BMI was (22.70±3.82) kg/m 2. The mean values of waist circumference, hip circumference, and calf circumference were (85.42±10.68) cm, (92.67±8.90) cm, and (31.08±4.76) cm, respectively. After controlling confounding factors, the results of the multiple linear regression model showed that for each increment of 1 μg/g·creatinine in creatinine-adjusted urinary cadmium, the change of BMI, waist circumference, hip circumference, and calf circumference in the high-level group was -0.28 (-0.37, -0.19) kg/m 2, -0.74 (-0.96, -0.52) cm, -0.78 (-0.96, -0.61) cm, and -0.20 (-0.30, -0.11) cm, respectively. The restrictive cubic splines curve showed a negative nonlinear association of creatinine-adjusted urinary cadmium with BMI ( Pnonlinear<0.001) and negative linear associations of creatinine-adjusted urinary cadmium with waist circumference ( Plinear<0.001), hip circumference ( Plinear<0.001), and calf circumference ( Plinear<0.001). Conclusion:Urinary cadmium level is significantly associated with decreased BMI, waist circumference, hip circumference and calf circumference among older adults over 65 years old in 9 longevity areas of China.

Objective:To investigate the association of urinary cadmium level with body mass index (BMI) and body circumferences among the older adults over 65 years old in 9 longevity areas of China.Methods:Subjects were older adults over 65 years old from the Healthy Aging and Biomarkers Cohort Study (HABCS) between 2017 and 2018 conducted in 9 longevity areas in China. A total of 1 968 older adults were included in this study. Information including socio-demographic characteristics, lifestyles, diet intake, and health status was collected by using questionnaires and physical examinations. Urine samples were collected to detect urinary cadmium and creatinine levels. Body circumferences included waist circumference, hip circumference and calf circumference. Subjects were divided into three groups (low:<0.77 μg/g·creatinine, middle:0.77-1.69 μg/g·creatinine, high:≥1.69 μg/g·creatinine) by tertiles of creatinine-adjusted urinary cadmium concentration. Multiple linear regression models were used to analyze the association of creatinine-adjusted urinary cadmium level with BMI and body circumferences. The dose-response relationship of creatinine-adjusted urinary cadmium concentration with BMI and body circumferences was analyzed by using restrictive cubic splines fitting multiple linear regression model.Results:The mean age of subjects was (83.34±11.14) years old. The median (Q1, Q3) concentration of creatinine-adjusted urinary cadmium was 1.13 (0.63, 2.09) μg/g·creatinine, and the BMI was (22.70±3.82) kg/m 2. The mean values of waist circumference, hip circumference, and calf circumference were (85.42±10.68) cm, (92.67±8.90) cm, and (31.08±4.76) cm, respectively. After controlling confounding factors, the results of the multiple linear regression model showed that for each increment of 1 μg/g·creatinine in creatinine-adjusted urinary cadmium, the change of BMI, waist circumference, hip circumference, and calf circumference in the high-level group was -0.28 (-0.37, -0.19) kg/m 2, -0.74 (-0.96, -0.52) cm, -0.78 (-0.96, -0.61) cm, and -0.20 (-0.30, -0.11) cm, respectively. The restrictive cubic splines curve showed a negative nonlinear association of creatinine-adjusted urinary cadmium with BMI ( Pnonlinear<0.001) and negative linear associations of creatinine-adjusted urinary cadmium with waist circumference ( Plinear<0.001), hip circumference ( Plinear<0.001), and calf circumference ( Plinear<0.001). Conclusion:Urinary cadmium level is significantly associated with decreased BMI, waist circumference, hip circumference and calf circumference among older adults over 65 years old in 9 longevity areas of China.

Objective To investigate the effective interval of programmed intermittent epidural bolus(PIEB)in labor analgesia with ropivacaine and hydromorphone.Methods A total of 101 puerpera with singleton pregnancy,head position,aged 20-40 years,BMI 20-35 kg/m2,ASA physical status Ⅰ orⅡ,gestational age 37-42 weeks,were randomly allocated into five different PIEB intervals groups:PIEB 40 minutes group(group P40,n=20),PIEB 50 minutes group(group P50,n=19),PIEB 60 minutes group(group P60,n=20),PIEB 70 minutes group(group P70,n=20),and PIEB 80 minutes group(group P80,n=22).The PIEB dose was fixed at 10 ml with the first bolus given 1 hour after the initial manual loading dose with subsequent boluses continued at intervals according to different group allocation.Analgesia was provided using PIEB with 0.1％ropivacaine combined with hydromorphone 15 μg/ml for a total of 12 ml.Based on effective analgesia rate(proportion of women who do not require additional analgesic drugs by the end of the first stage of labor).Probit regression was used to estimate median effective interval(EI50)and 90％effective interval(EI90).VAS pain scores before analgesia,20 minutes,1 hour,2,3,and 4 hours,at full opening of the cervix were recorded.The highest level of sensory blockade and motor blockade(modified Bromage score)were recorded,maternal adverse effects were recorded.Neonatal weight,1 minute and 5 minutes postnatal Apgar scores were recorded.Results Effective analgesia rates were 95.0％,84.2％,70.0％,55.0％,and 50.0％in groups P40,P50,P60,P70,and P80,respec-tively.The EI50 and EI90 were 76.5 minutes(95％CI 69.0-93.9 minutes)and 43.4 minutes(95％CI 17.6-52.7 minutes)analysing by Probit regression.There were no significant differences in VAS pain score at different time,maximum sensory block plane,modified Bromage score,incidence of maternal adverse re-actions and neonatal conditions between the two groups.Conclusion The EI50 and EI90 of PIEB 0.1％ropiv-acaine combined with hydromorphone 15 μg/ml for labor analgesia were 76.5 minutes(95％CI 69.0-93.9 minutes)and 43.4 minutes(95％CI 17.6-52.7 minutes),respectively.

Objective:To investigate the value of artificial intelligence (AI) cytomorphologic analysis system in the cytomorphological diagnosis and therapeutic evaluation of acute myeloid leukemia (AML).Methods:Bone marrow smear samples were collected from 150 patients with newly diagnosed and treated acute myeloid leukemia who were inpatients and outpatients at the Department of Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College from June 1, 2021 to July 31, 2022 for retrospective analysis. Among them, there were 50 patients in the newly diagnosed group, including 28 males and 22 females, with the onset age of 43.5(32.3,58.8)years. There were 100 patients in the post-treatment group, including 36 males and 64 females, with the onset age of 34.5(23.0,47.0)years. The results from cytomorphology expert were used as the gold standard and the Python 3.6.7 was used for analysis to evaluate the accuracy, sensitivity, and specificity of the AI cytomorphologic analysis system for blast cell recognition in AML diagnosis and treatment.Results:The proportion of blasts in AI analysis of 50 samples in the newly diagnosed group was≥20%, which met the diagnostic criteria of AML. AI analysis of blasts had an accuracy of 90.3%, sensitivity of 85.5%, and specificity of 98.0%. The correlation coefficient between AI and the proportion of blasts analyzed by experts was positively correlated( r=0.882, P<0.001). Meanwhile, in the post-treatment group, the sensitivity and specificity of AI analysis of blasts were 89.7% and 99.2%, respectively. The correlation coefficient between AI and the proportion of blasts analyzed by experts was positively correlated( r=0.957, P<0.001). According to AI analysis data, there are 8 samples in this group whose AI efficacy evaluation results on AML are inconsistent with expert analysis. Conclusion:AI cytomorphologic analysis system has high accuracy, sensitivity and specificity for blast cell recognition in AML morphological diagnosis and therapeutic evaluation.

Objective:To investigate the epidemiological characteristics, diagnosis, treat-ment and prognosis of gallbladder cancer in China from 2010 to 2017.Methods:The single disease retrospective registration cohort study was conducted. Based on the concept of the real world study, the clinicopathological data, from multicenter retrospective clinical data database of gallbladder cancer of Chinese Research Group of Gallbladder Cancer (CRGGC), of 6 159 patients with gallbladder cancer who were admitted to 42 hospitals from January 2010 to December 2017 were collected. Observation indicators: (1) case resources; (2) age and sex distribution; (3) diagnosis; (4) surgical treatment and prognosis; (5) multimodality therapy and prognosis. The follow-up data of the 42 hospitals were collected and analyzed by the CRGGC. The main outcome indicator was the overall survival time from date of operation for surgical patients or date of diagnosis for non-surgical patients to the end of outcome event or the last follow-up. Measurement data with normal distribu-tion were represented as Mean±SD, and comparison between groups was conducted using the t test. Measurement data with skewed distribution were represented as M( Q1, Q3) or M(range), and com-parison between groups was conducted using the U test. Count data were described as absolute numbers or percentages, and comparison between groups was conducted using the chi-square test. Univariate analysis was performed using the Logistic forced regression model, and variables with P<0.1 in the univariate analysis were included for multivariate analysis. Multivariate analysis was performed using the Logistic stepwise regression model. The life table method was used to calculate survival rates and the Kaplan-Meier method was used to draw survival curves. Log-rank test was used for survival analysis. Results:(1) Case resources: of the 42 hospitals, there were 35 class A of tertiary hospitals and 7 class B of tertiary hospitals, 16 hospitals with high admission of gallbladder cancer and 26 hospitals with low admission of gallbladder cancer, respectively. Geographical distribution of the 42 hospitals: there were 9 hospitals in central China, 5 hospitals in northeast China, 22 hospitals in eastern China and 6 hospitals in western China. Geographical distribution of the 6 159 patients: there were 2 154 cases(34.973%) from central China, 705 cases(11.447%) from northeast China, 1 969 cases(31.969%) from eastern China and 1 331 cases(21.611%) from western China. The total average number of cases undergoing diagnosis and treatment in hospitals of the 6 159 patients was 18.3±4.5 per year, in which the average number of cases undergoing diagnosis and treatment in hospitals of 4 974 patients(80.760%) from hospitals with high admission of gallbladder cancer was 38.8±8.9 per year and the average number of cases undergoing diagnosis and treatment in hospitals of 1 185 patients(19.240%) from hospitals with low admission of gallbladder cancer was 5.7±1.9 per year. (2) Age and sex distribution: the age of 6 159 patients diagnosed as gallbladder cancer was 64(56,71) years, in which the age of 2 247 male patients(36.483%) diagnosed as gallbladder cancer was 64(58,71)years and the age of 3 912 female patients(63.517%) diagnosed as gallbladder cancer was 63(55,71)years. The sex ratio of female to male was 1.74:1. Of 6 159 patients, 3 886 cases(63.095%) were diagnosed as gallbladder cancer at 56 to 75 years old. There was a significant difference on age at diagnosis between male and female patients ( Z=-3.99, P<0.001). (3) Diagnosis: of 6 159 patients, 2 503 cases(40.640%) were initially diagnosed as gallbladder cancer and 3 656 cases(59.360%) were initially diagnosed as non-gallbladder cancer. There were 2 110 patients(34.259%) not undergoing surgical treatment, of which 200 cases(9.479%) were initially diagnosed as gallbladder cancer and 1 910 cases(90.521%) were initially diagnosed as non-gallbladder cancer. There were 4 049 patients(65.741%) undergoing surgical treatment, of which 2 303 cases(56.878%) were initially diagnosed as gallbladder cancer and 1 746 cases(43.122%) were initial diagnosed as non-gallbladder cancer. Of the 1 746 patients who were initially diagnosed as non-gallbladder cancer, there were 774 cases(19.116%) diagnosed as gallbladder cancer during operation and 972 cases(24.006%) diagnosed as gallbladder cancer after operation. Of 6 159 patients, there were 2 521 cases(40.932%), 2 335 cases(37.912%) and 1 114 cases(18.087%) undergoing ultrasound, computed tomography (CT) or magnetic resonance imaging (MRI) examination before initial diagnosis, respec-tively, and there were 3 259 cases(52.914%), 3 172 cases(51.502%) and 4 016 cases(65.205%) undergoing serum carcinoembryonic antigen, CA19-9 or CA125 examination before initially diagnosis, respectively. One patient may underwent multiple examinations. Results of univariate analysis showed that geographical distribution of hospitals (eastern China or western China), age ≥72 years, gallbladder cancer annual admission of hospitals, whether undergoing ultrasound, CT, MRI, serum carcinoembryonic antigen, CA19-9 or CA125 examination before initially diagnosis were related factors influencing initial diagnosis of gallbladder cancer patients ( odds ratio=1.45, 1.98, 0.69, 0.68, 2.43, 0.41, 1.63, 0.41, 0.39, 0.42, 95% confidence interval as 1.21-1.74, 1.64-2.40, 0.59-0.80, 0.60-0.78, 2.19-2.70, 0.37-0.45, 1.43-1.86, 0.37-0.45, 0.35-0.43, 0.38-0.47, P<0.05). Results of multivariate analysis showed that geographical distribution of hospitals (eastern China or western China), sex, age ≥72 years, gallbladder cancer annual admission of hospitals and cases undergoing ultrasound, CT, serum CA19-9 examination before initially diagnosis were indepen-dent influencing factors influencing initial diagnosis of gallbladder cancer patients ( odds ratio=1.36, 1.42, 0.89, 0.67, 1.85, 1.56, 1.57, 0.39, 95% confidence interval as 1.13-1.64, 1.16-1.73, 0.79-0.99, 0.57-0.78, 1.60-2.14, 1.38-1.77, 1.38-1.79, 0.35-0.43, P<0.05). (4) Surgical treatment and prognosis. Of the 4 049 patients undergoing surgical treatment, there were 2 447 cases(60.435%) with complete pathological staging data and follow-up data. Cases with pathological staging as stage 0, stage Ⅰ, stage Ⅱ, stage Ⅲa, stage Ⅲb, stage Ⅳa and stage Ⅳb were 85(3.474%), 201(8.214%), 71(2.902%), 890(36.371%), 382(15.611%), 33(1.348%) and 785(32.080%), respectively. The median follow-up time and median postoperative overall survival time of the 2 447 cases were 55.75 months (95% confidence interval as 52.78-58.35) and 23.46 months (95% confidence interval as 21.23-25.71), respectively. There was a significant difference in the overall survival between cases with pathological staging as stage 0, stage Ⅰ, stage Ⅱ, stage Ⅲa, stage Ⅲb, stage Ⅳa and stage Ⅳb ( χ2=512.47, P<0.001). Of the 4 049 patients undergoing surgical treatment, there were 2 988 cases(73.796%) with resectable tumor, 177 cases(4.371%) with unresectable tumor and 884 cases(21.833%) with tumor unassessable for resectabi-lity. Of the 2 988 cases with resectable tumor, there were 2 036 cases(68.139%) undergoing radical resection, 504 cases(16.867%) undergoing non-radical resection and 448 cases(14.994%) with operation unassessable for curative effect. Of the 2 447 cases with complete pathological staging data and follow-up data who underwent surgical treatment, there were 53 cases(2.166%) with unresectable tumor, 300 cases(12.260%) with resectable tumor and receiving non-radical resection, 1 441 cases(58.888%) with resectable tumor and receiving radical resection, 653 cases(26.686%) with resectable tumor and receiving operation unassessable for curative effect. There were 733 cases not undergoing surgical treatment with complete pathological staging data and follow-up data. There was a significant difference in the overall survival between cases not undergoing surgical treatment, cases undergoing surgical treatment for unresectable tumor, cases undergoing non-radical resection for resectable tumor and cases undergoing radical resection for resectable tumor ( χ2=121.04, P<0.001). (5) Multimodality therapy and prognosis: of 6 159 patients, there were 541 cases(8.784%) under-going postoperative adjuvant chemotherapy and advanced chemotherapy, 76 cases(1.234%) under-going radiotherapy. There were 1 170 advanced gallbladder cancer (pathological staging ≥stage Ⅲa) patients undergoing radical resection, including 126 cases(10.769%) with post-operative adjuvant chemotherapy and 1 044 cases(89.231%) without postoperative adjuvant chemo-therapy. There was no significant difference in the overall survival between cases with post-operative adjuvant chemotherapy and cases without postoperative adjuvant chemotherapy ( χ2=0.23, P=0.629). There were 658 patients with pathological staging as stage Ⅲa who underwent radical resection, including 66 cases(10.030%) with postoperative adjuvant chemotherapy and 592 cases(89.970%) without postoperative adjuvant chemotherapy. There was no significant difference in the overall survival between cases with postoperative adjuvant chemotherapy and cases without postoperative adjuvant chemotherapy ( χ2=0.05, P=0.817). There were 512 patients with pathological staging ≥stage Ⅲb who underwent radical resection, including 60 cases(11.719%) with postoperative adjuvant chemotherapy and 452 cases(88.281%) without postoperative adjuvant chemotherapy. There was no significant difference in the overall survival between cases with postoperative adjuvant chemo-therapy and cases without post-operative adjuvant chemo-therapy ( χ2=1.50, P=0.220). Conclusions:There are more women than men with gallbladder cancer in China and more than half of patients are diagnosed at the age of 56 to 75 years. Cases undergoing ultrasound, CT, serum CA19-9 examination before initial diagnosis are independent influencing factors influencing initial diagnosis of gallbladder cancer patients. Preoperative resectability evaluation can improve the therapy strategy and patient prognosis. Adjuvant chemotherapy for gallbladder cancer is not standardized and in low proportion in China.

Objective: To understand the homology and resistance characteristics of Streptococcus pneumoniae (S. pneumoniae) in healthy preschool children, so as to provide basis for disease transmission prevention and rational use of antibiotics. Methods: Stratified cluster random sampling method was used to sample 1 829 healthy children from six kindergartens in Shunde District, Foshan City. Nasal swabs were taken and tested for S. pneumoniae. Multi locus sequence typing was used for homology analysis. The Chi squared test and random forest analysis were used to explore the resistance characteristics. Results: The nasal carriage rate of S. pneumoniae and multidrug resistant S. pneumoniae (MDRSP) in children were 22.5%(412/1 829) and 21.3%(390/1 829), respectively. Homology analysis in sequence types showed that the total homology rates of 6 kindergartens were 93.5%(87/93), 91.1% (72/79), 89.2%(58/65), 88.9%(64/72), 86.2%(50/58), 77.8%(35/45), respectively. It was found that the highest homology rate was 82.8% (48/58) within class and 93.1% (81/87) between classes. S. pneumoniae was mainly resistant to azithromycin (97.1%, 400/412), erythromycin (92.0%, 379/412) and tetracycline (91.5%, 377/412). The dominant multidrug resistance pattern of MDRSP isolates was not sensitive to azithromycin, erythromycin, cotrimoxazole, tetracycline and clindamycin. Random forest analysis indicated that the important phenotypic markers associated with MDRSP were resistance to azithromycin, cotrimoxazole, tetracycline, clindamycin and erythromycin(MDG=8.94, 6.92, 5.80, 4.84, 2.58). Conclusion The risk of cross transmission of S. pneumoniae among preschool children is high, and direct contact is the main way of transmission. Consequently, kindergartens and health departments should take effective measures to effectively prevent and block the spread of Streptococcus pneumoniae.

Objective:To investigate the risk factors of moderate to severe cancer-related fatigue (CRF) in patients undergoing chemotherapy of prostate cancer, and to construct a nomogram model to predict the occurrence of CRF.Methods:Using the case data questionnaire, Brief Fatigue Inventory, Social Support Rating Scale and International Prostate Symptom Scores, 724 patients of prostate cancer treated by chemotherapy in Shanghai Tenth People′s Hospital from August 2016 to June 2021 were selected and were treated with 1∶1 ratio, and the indexes of the moderate and severe CRF group (216 cases) and the non-moderate and severe CRF group (216 cases) were compared. According to the ratio of 7∶3, the envelope method was used to divide into training set and validation set. The independent risk factors of moderate and severe CRF were explored by univariate analysis and multivariate Logistic regression analysis, and the risk prediction model was established and the nomogram model was constructed. The C-index and area under ROC curve were used to verify the prediction effect of the model.Results:Multivariate Logistic regression analysis showed that BMI ranged from 24.0 to 27.9 kg/m 2 ( OR=1.733), BMI≥28.0 kg/m 2 ( OR=3.126), neutropenia occurred during chemotherapy ( OR=1.747), chemotherapy course >6 months ( OR=1.893), moderate social support level ( OR=1.244), low social support level ( OR=2.434), mild urinary tract symptoms ( OR=1.264), moderate urinary tract symptoms ( OR=3.371) and severe urinary tract symptoms ( OR=5.297) were independent risk factors for moderate and severe CRF. The nomogram model constructed according to the above risk factors was internally verified by the training set and the validation set, and its C-index was 0.854 and 0.741 respectively. The area under ROC curve training set was 0.823, and the validation set was 0.733. Conclusions:The nomogram model can effectively predict the occurrence of moderate to severe CRF in patients with prostate cancer undergoing chemotherapy.

Objective: To explore clustering and risk factors of Staphylococcus aureus (S. aureus) carriage among kindergarten children in Liuzhou. Methods: Two sided nasal swabs were collected from 1 702 children in Liuzhou from April to June 2018. Parents of all the children were investigated by questionnaires. The random effect Logistic regression was used to analyze the clustering and risk factors of S. aureus carriage. Results: The carriage rate of S. aureus among kindergarten children was 16.3%. The randomeffect Logistic regression model indicated that the class-level random effect of S. aureus carriage among children was statistically significant(Z=2.12, P<0.01). Children aged 6 to 7 years (OR=2.18, 95%CI=1.45-3.27) and 5 years (OR=1.65, 95%CI=1.08-2.50) had higher carriage rates of S. aureus than those aged 3-4 years. The history of antibiotic using (OR=1.45, 95%CI=1.05-2.01) and skin and soft tissue infections (OR=1.36, 95%CI=1.04-1.79) in the previous year were risk factors of S. aureus carriage among children. Conclusion The class level clustering of S. aureus carriage is observed in healthy children. Age, history of antibiotic usage and history of skin and soft tissue infections are associated with risk of S. aureus carriage among preschool children.

Objective:To investigate the role of Bruton's tyrosine kinase (BTK) in pyroptosis of intestinal cells caused by endotoxin/lipopolysaccharide (LPS) in scalded mice.Methods:The experimental research method was applied. One hundred and twenty-eight male C57BL/6 mice aged 6-8 weeks were divided into sham injury group, scald alone group, scald+LPS group, scald+LPS+3 mg/kg LFM-A13 group, scald+LPS+10 mg/kg LFM-A13 group, and scald+LPS+30 mg/kg LFM-A13 group. There were 8 mice in sham injury group, and there were 24 mice in the other 5 groups, respectively. Mice in 5 scald groups were inflicted with 10% total body surface area full-thickness scald on the back, and mice in sham injury group were sham injured on the back. At post injury hour (PIH) 0 (immediately), mice in sham injury group and scald alone group were intraperitoneally injected with normal saline, mice in scald+LPS group were intraperitoneally injected with LPS, and mice in scald+LPS+3 mg/kg LFM-A13 group, scald+LPS+10 mg/kg LFM-A13 group, and scald+LPS+30 mg/kg LFM-A13 group were intraperitoneally injected with LPS and LFM-A13 in corresponding doses. Mice in sham injury group were sacrificed at PIH 0 to collect serum and intestinal tissue, and 8 mice in each group of 5 scald groups were sacrificed at PIH 0, 12, and 24 to collect intestinal tissue and serum at PIH 12. Immunohistochemistry was used to detect phosphorylation of BTK in intestinal tissue of mice. Western blotting was used to detect the protein expressions of phosphorylated BTK (p-BTK), cleaved cysteine aspartic acid specific protease 1 (caspase-1), and cleaved caspase-11 in intestinal tissue of mice. Enzyme-linked immunosorbent assay method was used to detect interleukin-1β (IL-1β) in serum and intestinal tissue of mice. Data were statistically analyzed with one-way analysis of variance and least significant difference test.Results:There was no obvious phosphorylation of BTK in intestinal tissue of mice in 6 groups at PIH 0 and scald alone group at PIH 12 and 24. Phosphorylation of BTK in intestinal tissue of mice in scald+LPS group at PIH 12 and 24 were obviously increased compared with those in scald alone group. Phosphorylation of BTK in intestinal tissue of mice in scald+LPS+3 mg/kg LFM-A13 group, scald+LPS+10 mg/kg LFM-A13 group, and scald+LPS+30 mg/kg LFM-A13 group were obviously decreased compared with those in scald+LPS group, and the degrees of decline gradually increased with increase of dose in LFM-A13. Compared with (0.130±0.010) of sham injury group and (0.120±0.040 and 0.110±0.040) of scald alone group, protein expressions of p-BTK in intestinal tissue of mice in scald+LPS group at PIH 12 and 24 were obviously increased (0.470±0.090 and 0.430±0.080, P<0.01). Compared with those in scald+LPS group, protein expressions of p-BTK in intestinal tissue of mice in scald+LPS+3 mg/kg LFM-A13 group at PIH 24, and scald+LPS+10 mg/kg LFM-A13 group and scald+LPS+30 mg/kg LFM-A13 group at PIH 12 and 24 were obviously decreased (0.280±0.060, 0.300±0.120, 0.150±0.050, 0.280±0.090, 0.140±0.040, P<0.05 or P<0.01). Compared with those in scald+LPS+3 mg/kg LFM-A13 group, protein expressions of p-BTK in intestinal tissue of mice in scald+LPS+10 mg/kg LFM-A13 group and scald+LPS+30 mg/kg LFM-A13 group at PIH 24 were obviously decreased ( P<0.01). Compared with those in sham injury group and scald alone group, protein expressions of cleaved caspase-1 and caspase-11 in intestinal tissue of mice in scald+LPS group were obviously increased at PIH 12 and 24 ( P<0.01). Compared with those in scald+LPS group, protein expressions of cleaved caspase-1 at PIH 12 and cleaved caspase-11 at PIH 12 and 24 in intestinal tissue of mice in scald+LPS+3 mg/kg LFM-A13 group and protein expressions of cleaved caspase-1 and caspase-11 in intestinal tissue of mice in scald+LPS+10 mg/kg LFM-A13 group and scald+LPS+30 mg/kg LFM-A13 group at PIH 12 and 24 were obviously decreased ( P<0.01). Compared with those in scald+LPS+3 mg/kg LFM-A13 group, protein expressions of cleaved caspase-1 and caspase-11 in intestinal tissue of mice in scald+LPS+10 mg/kg LFM-A13 group and scald+LPS+30 mg/kg LFM-A13 group at PIH 12 and 24 were obviously decreased ( P<0.05 or P<0.01). At PIH 12, content of IL-1β in intestinal tissue and serum of mice in scald+LPS group were obviously higher than those in sham injury group and scald alone group ( P<0.01), and content of IL-1β in intestinal tissue and serum of mice in scald+LPS+30 mg/kg LFM-A13 group were obviously lower than those in scald+LPS group ( P<0.01). Conclusions:Phosphorylation of BTK is related to increases of cleaved caspase-1 and caspase-11 in intestinal tissue, and IL-1β content in intestinal tissue and serum of scalded septic mice caused by LPS. Phosphorylation of BTK mediates intestinal cell pyroptosis of scalded mice caused by LPS. Inhibiting phosphorylation of BTK can alleviate intestinal cell pyroptosis of scalded mice, with protective effect on intestinal injury intestine.