Objective To understand the distribution of M protein gene (emm) of group A streptococcus (GAS) infections among children in Xicheng District of Beijing. Methods Throat swab samples from scarlet fever and pharyngeal infection cases were collected in sentinel hospitals of Xicheng District, Beijing from 2011 to 2024. GAS strains were isolated and identified, and emm gene was amplified and sequenced by PCR to determine the genotype. The differences in emm genotype between different groups were compared. Results A total of 3 130 throat swab samples were collected, and 400 GAS strains were isolated, with a positive rate of 12.78%. The highest positive rate was 19.93% in 2011. The positive rate of scarlet fever (45.71%) was higher than that of pharyngeal infection (6.14%) (P<0.001). There were 391 emm gene positive strains, and the differences in the positive rate of emm gene among different cases were statistically significant (P<0.001). A total of 7 genotypes and 27 gene subtypes were detected. Among different groups, the emm genotypes were mainly emm12 and emm1. The emm gene subtypes were mainly emm12.00 and emm1.00. Except for some years, the genotypes and their subtypes were dominated by emm12 and emm12.00, and the distribution differences of the two major genotypes and their subtypes were statistically significant from 2011 to 2019 (P<0.001). There were differences in genotypes and subtypes among different age groups (P=0.002). Conclusion The dominant types of emm genes in group A streptococcus infections among children were emm12 and emm1 in Xicheng District of Beijing from 2011 to 2024, and the dominant gene subtypes were emm12.00 and emm1.00. It is necessary to comprehensively strengthen the monitoring of the epidemic situation and genotype, timely grasp the distribution and variation of emm gene.

Objective: To analyze the epidemiological and molecular characteristics of norovirus outbreaks in schools in Xicheng District of Beijing from 2017 to 2022, so as to provide evidence for the prevention and control of norovirus outbreaks in schools. Methods: Data of norovirus outbreaks in schools in Xicheng District, Beijing during 2017 to 2022 were collected and analyzed by descriptive epidemiological methods. Realtime PCR was used to detect the nucleic acid of group GⅠand GⅡnorovirus, the positive norovirus nucleic acid samples were sent to Beijing Center for Disease Control and Prevention for molecular typing. Results: From 2017 to 2022, 185 norovirus outbreaks were reported in schools in Xicheng District, including 166 cluster outbreaks and 19 outbreaks. A total of 2 044 cases were reported, with a total attack rate of 13.92%. There were two peaks in the outbreak time, which were from March to June after the spring semester and from October to December after autumn semester. Primary schools were the most common place of occurrence (101 cases), followed by nursery institutions (68 cases) and secondary schools (16 cases). There were statistically significant differences in the incidence rates among different sites(12.37%, 22.78%, 8.47%, χ2=263.34, P<0.01). There were significant differences in the incidence of vomiting, diarrhea, nausea and stomachache among different students (χ2=263.33, 90.58, 20.42, 30.29, P<0.01). Vomiting was the main symptom in primary school and nursery school children (96.41%, 98.28%), and the diarrhea rate was higher in middle school students (68.22%). The outbreaks were mainly caused by type GⅡ norovirus. The genotype from 2017 to 2021 showed the characteristics of diversity, mainly GⅡ.2[P16], but there was no significant advantage for the GⅡ.2 [P16] during 2019 to 2021. Conclusions The norovirus outbreak in schools in Xicheng district of Beijing from 2017 to 2022 are mainly caused by GⅡ type genome. The main genotype is GⅡ.2[P16]. Norovirus infection mainly occurred in primary schools and kindergartens. For the vulnerable populations, it is necessary to improve the capacity to early identification, student infectious disease management, active infection control and prevention measures, and pathogen surveillance and sporadic case monitoring.

AIM: To investigate the effect of dapagliflozin on myocardial injury in type 1 diabetes mice and its mechanism. METHODS: Normal C57BL / 6J male mice were randomly divided into normal control group (Control), diabetes cardiomyopathy group (DCM) and dapagliflozin group (DAPA). The model of diabetes was induced by streptozotocin (STZ) and given maintenance feed. DAPA group was given 10 mg · kg

Objective To investigate the pathology, epidemiology of severe pneumonia in Xicheng District of Beijing. Methods From 2014 to 2020, in 3 sentinel hospitals, collected and detected the respiratory tract specimens of the severe pneumonia patients. Multiple pathogens including Stenotrophomonas maltophilia, Streptococcus pyogenes, Staphylococcus aureus, Klebsiella Pneumoniae, Haemophilus influenzae, Legionella pneumophila, Mycobacterium tuberculosis, Acinetobacter baumannii, Moraxella catarrhalis, Escherichia coli, Streptococcus pneumoniae, Pseudomonas aeruginosa, Pneumocystis,Parainfluenza virus, Bocavirus, Rhinovirus, Coronavirus, Influenza, Human metapneumovirus, Adenovirus, Respiratory syncytial virus, Enterovirus, Mycoplasma pneumoniae, Chlamydia pneumoniae were detected with PT-PCR. Analyze epidemic characteristics of the cases. Results Of the 1 247 respiratory samples cultured during the period from 2014 to 2020, 560(44.91%) are positive. The positive rates of virus(29.91%) is higher than Bacteria(20.21%). The top five pathogens were Acinetobacter baumannii(9.22%), Pseudomonas aeruginosa(8.26%), Stenotrophomonas maltophilia(7.78%), Klebsiella Pneumoniae（6.74%） and Parainfluenza virus（6.58%）. Conclusion There was a variety of pathogen in the severe pneumonia patients. Acinetobacter baumannii, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Klebsiella Pneumoniae and Parainfluenza virus were the main pathogens of respiratory infections in Xicheng district of Beijing. It is necessary to strengthen the surveillance of the disease.

Objective:To analyze the expression of LC3-Ⅱ and ATF3 in hepatocellular carcinoma (HCC) , to explore the relationship between their expression and the prognosis of patients with HCC, and to analyze the expression correlation betweenLC3-Ⅱ and ATF3 in HCC tissues.Methods:Immunohistochemical method was used to detect the expression of LC3-Ⅱ and ATF3 protein in HCC tissue and corresponding paracancerous tissue specimens, to analyze the relationship between these two proteins and the patient's clinicopathological characteristics as well as survival time. Western blot was used to detect the expression of LC3-Ⅱ and ATF3 proteins in fresh HCC tissues and corresponding paracancerous tissue.Results:The expression of LC3-Ⅱ and ATF3 inparacancerous tissues was significantly higher than that in HCC tissues. The expression levels of were related to HCC histopathological grade and venous tumor thrombus (all P<0.05), but were not related to age, gender, and serum alpha-fetoprotein, tumor diameter, HBsAg, etc (all P>0.05) . The low expression of LC3-Ⅱ and ATF3 was significantly related to the poor prognosis of patients with HCC (both P<0.05). Conclusions:Both LC3-Ⅱ and ATF3 protein expression are related to the occurrence and development of HCC. The combined detection of LC3-Ⅱ and ATF3 is helpful for the assessment of the malignant degree of HCC and it is expected to become an important indicator for judging the prognosis of patients.

Objective:To investigate the association of single nucleotide polymorphism at the estrogen receptor 1(ESR1) gene rs1801132 with the risk of brick-tea type skeletal fluorosis.Methods:The typical brick-tea type fluorosis areas in Qinghai, Xinjiang, and Inner Mongolia were selected as the survey sites for a cross-sectional study. An epidemiological questionnaire was conducted by the staffs on the sites for participants older than 16 years, and physical examination and X-ray diagnosis were performed. Brick tea, blood, and urine samples were collected at the same time. The diagnosis of skeletal fluorosis through X-ray was based on the "Diagnostic Criteria for Endemic Skeletal Fluorosis" (WS/T 192-2008); The determination of tea's fluoride and urinary fluoride was performed by fluoride ion-selective electrode method; gene sequencing analysis of rs1801132 locus of ESR1 gene was done by Sequenom MassARRAY flight mass spectrometry system.Results:A total of 994 patients were included in this study. The total prevalence of skeletal fluorosis was 23.9% (238/994). The prevalence of skeletal fluorosis in Tibetans(39.9%, 123/308) was higher than those of Mongolian and Han nationality [22.2% (58/261), 13.4% (57/425), χ 2=20.435, 67.811, P < 0.05]. Based on binary logistic analysis, the daily tea fluoride intake ≤ 3.5 mg, urinary fluoride content ≤1.6 mg/L, and age ≤45 years were used as the reference groups, and then, when the daily tea fluoride intake > 7.0 mg ( OR=2.865, 95% CI: 1.923-4.268), urinary fluoride content > 1.6-3.2 mg/L ( OR=2.368, 95% CI: 1.686-3.326) and > 3.2 mg/L ( OR=3.559, 95% CI: 2.401-5.276), the age > 45-65 years old ( OR=2.361, 95% CI: 1.603-3.477) and > 65 years old ( OR=4.556, 95% CI: 2.845-7.296), the risk of fluorosis was higher than that of the reference group, respectively. When the daily tea fluoride intake was > 3.5-7.0 mg and the level of urinary fluoride was > 1.6-3.2 mg/L, G allele had a protective effect on skeletal fluorosis in Mongolian population (adjusted OR=0.207, 95% CI: 0.044-0.974); when the daily tea fluoride intake was > 3.5-7.0 mg, gender was male group, G allele had a protective effect on skeletal fluorosis in Han population (adjusted OR=0.315, 95% CI: 0.112-0.887). Conclusion:The single nucleotide polymorphism of the rs1801132 locus at the ESR1 gene may be associated with the risk of susceptibility to brick-tea type skeletal fluorosis in Mongolian and Han nationality.

Objective:To study and establish a high-throughput and rapid detection method for fluorine ion content in water based on 96-well plate and microplate reader, and to evaluate its performance.Methods:According to the principle of blue ternary complex formed by reaction of fluorine ion with fluorine reagent and lanthanum nitrate, the absorbance of the complex at the wavelength of 650 nm was proportional to the concentration of fluoride ion, and the content of fluoride ion in water samples was quantitatively determined by microplate reader. The accuracy, precision and detection limit of the method were evaluated by the standard recovery rate method and the reference material method.Results:The linear correlation coefficient of the standard curve of this method was > 0.999; the standard recovery rates of different concentrations were 99.00% - 103.33% in the accuracy experiment of this method, and the average recovery rate was 101.08%. In the standard material method, the measured values are all within the calibration range of the standard solution. The relative standard deviation of water samples with different concentrations was ≤10% in the precision experiment and the detection limit was 0.06 mg/L.Conclusion:The method has good accuracy and precision, low detection limit and small sample consumption, and this method can greatly improve the detection efficiency.

Objective: To understand the situation of inoculation and influencing factors of children in the Xicheng District of Beijing after the enterovirus 71（EV71）vaccine was marketed . Methods: A questionnaire survey was conducted among the parents of children aged 6 to 35 months in the vaccination clinics in Xicheng District from May to September 2017. Demographic characteristics,awareness of hand-foot-mouth disease and EV71 vaccine,the access to these knowledge,acceptance of the vaccine price and advice on the management were collected. The influencing factors for EV71 vaccination were analyzed by multivariate logistic regression . Results: There were 1 850 out of 1 885 parents investigated,with the effective rate of 98.14%. The EV71 vaccination rate of children aged 6 to 35 months was 27.03%. The awareness rate of hand-foot-mouth disease and EV71 vaccine in parents was 55.95%. The results of logistic regression analysis showed that the parents with the annual household income of 50 000 yuan and above （OR50 000 yuan- =2.665,95%CI：1.535-4.628;OR100 000 yuan-=4.732,95%CI：2.830-7.914;OR200 000 yuan-=3.576,95%CI：2.084-6.135）,with acceptance of 100 yuan and above in the price of the vaccine （OR100 yuan-= 9.487,95%CI：6.873-13.096;OR200 yuan-=5.940,95%CI：3.465-10.183;OR300-500 yuan-=2.415,95%CI：1.183-4.933）,with more than two sources of the information for EV71 vaccine （OR=3.062,95%CI：2.306-4.065）,without the care about the management of the EV71 vaccine（OR=1.650,95%CI：1.156-2.356）were more likely to have their children vaccinated;while the parents who lived in bungalows and cabinets （OR=0.589,95%CI：0.386-0.899）,who were medical staff（OR=0.240,95%CI：0.118-0.487）,who were not residents of Beijing（OR=0.587,95%CI：0.399-0.863）,who had more than one children （OR=0.338,95%CI：0.236-0.483） were less likely to have their children vaccinated . Conclusion The parents of children aged below three years in Xicheng District of Beijing should improve their awareness of hand-foot-mouth disease and EV71 vaccine. The vaccination rate of EV71 were mainly related to the registration,occupation,number of children, household income,the access to the information about vaccine,acceptance of the vaccine price and advice on the management in parents.

Objective: The objective was to identify the incidence of influenza-like syndromes and related health behavior factors among Beijing residents. Methods: From December 6, 2013 to January 16, 2014, we selected 150 villages or communities from 30 towns or streets as survey locations using a multi-stage random sampling method, and then conducted a cross-sectional study among 7 354 residents who aged 18 years or above and had live in Beijing for more than a half year using self-administered anonymous questionnaires, and totally 7 327 valid questionnaires are collected. The questionnaire consisted of demographic information, self-reported influenza-like syndromes in the past two weeks, and health behaviors. Multiple logistic regression models were used to identify the factors associated with self-reported influenza-like syndromes. Results: The mean (SD) age of the partcipants was 44.6 (15.2) years. Among them, 6.9% (506 cases) reported having influenza like illness during the past two weeks. The multiple logistic regression analysis indicated that regular physical exercise, optimal hand hygiene, and avoidance of going to the crowded places during respiratory infectious disease epidemics were significantly associated with a lower likelihood of reporting influenza-like syndromes, compared with those without regular physical exercises, without optimal hand hygiene, and not avoiding going to the crowded places, and the OR(95%CI) were 0.80 (0.66-0.97), 0.75 (0.57-0.99) and 0.80 (0.65-0.98), respectively. Conclusion Personal health behaviors were associated with the incidence of respiratory infectious diseases such as influenza in Beijing, and future interventions to improve personal hygiene behaviors are needed to prevent the spread of respiratory infectious diseases.

Objective To investigate the effects of fluoride on trabecular bone of the tibia and lumbar in BALB/c mice.Methods Totally 64 four-week-old BALB/c mice were randomly divided into 4 groups by weight,16 per group:control group (treated with distilled water) and 3 sodium fluoride (NaF) exposure groups (treated with NaF at 25,50 and 100 mg/L F-),respectively.At 12 weeks,mice were killed and blood,two hind limbs and lumbar were collected.Bone fluoride content and incidence rates of dental fluorosis were determined.Serum content of alkaline phosphatase (AKP) and acid phosphatase (ACP) were detected by micro enzyme labeled method.The ultrastructure of osteoblasts and osteoclasts in lumbar were observed via transmission electron microscope.The pathological changes of the trabecular bone of the tibia and the lumbar were observed under optical microscope,the percentage of trabecular area (％Tb.Ar) was measured with Image-Pro Plus (IPP) software.Results Bone fluoride contents of low,middle and high fluoride groups [(1 828.62 ± 102.93),(3 308.27 ± 185.63),(4 933.36 ± 301.16) mg/kg] were higher than that of the control group [(775.23 ± 92.56) mg/kg,all P ＜ 0.05].The incidences of dental fluorosis in the 4 groups were 0(0/16),47％(7/15),93％(14/15) and 100％(16/16),respectively;the difference was statistically significant (x2 =27.23,P ＜ 0.05).In middle and high fluoride groups,serum AKP [(18.30 ± 1.99),(24.50 ± 3.14) king unit/100 ml] and ACP [(11.97 ± 1.73),(11.31 ± 1.46) king unit/100 ml] were significantly higher than those of control [(14.63 ± 1.21),(9.07 ± 1.47) king unit/100 ml,respectively,all P ＜ 0.05].Under the electron microscope,osteoblast had developed organelles in each fluoride group,rough endoplasmic reticulum,Golgi body,and mitochondria were abundant,and nucleolus was obvious in the osteoblast.Osteoclast was rich in mitochondria,ruffled border clear and distributed phagocytic vacuoles in low fluoride group and middle fluoride group.Compared with the control group (17.03 ± 3.73),HE staining of tibia ％Tb.Ar in high fluoride group (28.79 ± 8.26) was significantly increased (P ＜ 0.05).The lumbar spine ％Tb.Ar in low,middle and high fluoride groups (15.87 ± 2.59,18.28 ± 0.89,21.99 ± 1.81) were higher than that of the control group (12.06 ± 1.76,all P ＜ 0.05].Conclusions BALB/c mice could be used as a model of skeletal fluorosis.Osteoblast and osteoclast are activated in BALB/c mice with skeletal fluorosis.Bone formation is more obvious than bone resorption and bone mass is increased.What is more,bone mass has increased more significantly in the lumbar spine of mice.