Objective: To analyze the epidemiological characteristics, associated factors, and vaccine effectiveness of two pertussis cluster outbreaks in two primary schools in Yangzhong City in 2025, so as to provide evidence for school based epidemic prevention and control. Methods: From August 26 to 30, 2025, a pertussis questionnaire was administered to the epidemic affected classes of two primary schools (school A and school B) in Yangzhong City. A descriptive epidemiological retrospective analysis was used to characterize the pertussis cluster outbreaks in Yangzhong City from March to July 2025. A 1∶5 matched case control study (79 cases, 395 controls) was performed. Multivariate Logistic regression was used to identify associated factors, and the clinical symptom incidence rates, types of pertussis containing vaccines, and timeliness of vaccination were compared between groups using Fisher s exact test. Results: From March to July 2025, a total of 79 pertussis cases were reported in the two schools, with attack rates of 1.33% and 1.01%, respectively. Cases were predominantly aged 7-8 years (85.37% in school A, 73.68% in school B), and the main clinical manifestation was productive cough (63.29%). The pneumonia incidence rate among hospitalized cases ( 57.14 %) was higher than that among nonhospitalized cases(4.17%)(Fisher s exact test, P <0.01). The interval from the last dose to onset was concentrated at 6 to <7 years (44 cases). Logistic regression showed that children exposed to secondhand smoke in daily life ( OR = 3.86 ), those whose desk mates or front/back desk mates took leave due to cough ( OR =4.67), and those whose dining table mates or front/back table mates took leave due to cough ( OR =3.67) had significantly higher risks of pertussis (all P <0.05). A high proportion of both the case group and the control group received the acellular DTaP vaccine (97.47% and 96.96%, respectively),while a low proportion received the pentavalent vaccine (1.27% and 3.04%, respectively). Additionally, one case received only three doses of the acellular DTaP vaccine.The difference in vaccine type distribution between the two groups was not statistically significant (Fisher s exact test, P =0.31). Conclusions The outbreaks represent breakthrough infections under high vaccine coverage. Close contact and secondhand smoke exposure are the main risk factors. A booster immunization strategy with diphtheria-tetanus-pertussis vaccine should be implemented for school aged children.

Objective:To investigate the acute effects of persistent high exposure to atmospheric fine particulate matter (PM 2.5) on residents' outpatient visits for respiratory diseases. Methods:We collected daily outpatient records from 92 hospitals in 13 cities across the Beijing-Tianjin-Hebei region, along with daily PM 2.5, nitrogen dioxide (NO 2), and meteorological data from 2013 to 2018. Five persistent high PM 2.5 exposure scenarios were defined in terms of daily mean PM 2.5 concentrations (>75 μg/m 3 and >150 μg/m 3), duration (≥2 days and ≥3 days), and whether or not there was concurrent exposure to high levels of NO 2 (daily mean NO 2 concentration >50 μg/m 3). A two-stage statistical analysis strategy based on a generalized linear model was applied to conduct a time-series analysis to assess the exposure-response relationship between persistent high PM 2.5 exposure scenarios and residents' outpatient visits for a variety of respiratory diseases, and to estimate excess outpatient visits. Results:During the period, M ( Q1, Q3) PM 2.5 and NO 2 concentrations were 61.2 (42.3, 95.1) μg/m 3 and 40.2 (31.4, 54.4) μg/m 3, respectively, and the daily respiratory disease outpatient visits were 57 (52, 66) cases. When compared with non-permanent high PM 2.5 exposure periods, exposure scenarios with PM 2.5 >75 μg/m 3 and lasting for ≥2 days caused an increased risk of outpatient visits for respiratory diseases by 2.10% (95% CI: 1.44%-2.77%), and resulted in 43 787 (95% CI: 30 025-57 757) excess visits; in this scenario, the concurrent exposure to high levels of NO 2 had a greater acute effect on respiratory disease visits than the absence of exposure to high levels of NO 2 ( P<0.001). The risk of respiratory disease visits increased substantially by 4.41% (95% CI: 3.15%-5.68%) when the daily mean PM 2.5 concentration exceeded 150 μg/m 3 for ≥2 days. Subgroup disease analyses showed that scenarios with daily mean PM 2.5 concentrations exceeding 75 μg/m 3 for ≥3 days caused a significant increase in the risk of lower respiratory tract infections, chronic lower respiratory disease, and asthma visits. Conclusions:Sustained persistent high PM 2.5 exposure increases the risk of outpatient visits for various respiratory diseases; concurrent exposure to high concentrations of NO 2 leads to a greater risk of visiting the clinic, suggesting that the prevention and control of PM 2.5 pollution should be synchronized with the control of mobile source emissions, to synergistically manage the compound pollution of PM 2.5 and NO 2 in the atmosphere.

Objective:To evaluate the relationship between sevoflurane preconditioning-induced reduction of cognitive impairment and hippocampal necroptosis after cardiopulmonary bypass (CPB) in rats.Methods:Sixty SPF healthy male Sprague-Dawley rats, aged 6 months, weighing 400-450 g, were divided into 4 groups ( n=15 each) using the random number table method: control group (group C), sevoflurane group (Sev group), CPB group and CPB+ sevoflurane preconditioning group (CPB+ Sev group). The rats were exposed to 0.4% sevoflurane for 2 h in CPB+ Sev group and Sev group. The CPB model was established at 30 min after the end of sevoflurane preconditioning in CPB+ Sev group. The open field test was performed to assess the autonomic movement ability on the 2nd day after CPB. The Morris water maze test was used to assess the cognitive function on the 3rd day after CPB. The hippocampal tissues were removed after the end of the Morris water maze test for determination of the necroptosis rate and cytosolic calcium concentration of hippocampal neuron ([Ca 2+ ] i) (by flow cytometry) and the expression of phosphorylated receptor-interacting protein kinase 1 (p-RIPK1), phosphorylated RIPK3 and phosphorylated mixed-lineage kinase-like domain (p-MLKL) (by Western blot) and for microscopic examination of the ultrastructure of hippocampal neurons (by transmission electron microscopy). Results:There was no statistically significant difference in the parameters of the open field test among the four groups ( P>0.05). Compared with group C, the escape latency was significantly prolonged, the number of crossing the original platform was decreased, the time of staying at the original platform quadrant was shortened, the hippocampal necroptosis rate and [Ca 2+ ] i were increased, the expression of p-RIPK1, p-RIPK3 and p-MLKL was up-regulated ( P<0.05), the organelles of hippocampal neurons swelled, lysosomes broke, and some chromatin in nuclei dissoluted in CPB group. Compared with CPB group, the escape latency was significantly shortened, the number of crossing the original platform was increased, the time of staying at the original platform quadrant was prolonged, the hippocampal necroptosis rate and [Ca 2+ ] i were decreased, the expression of p-RIPK1, p-RIPK3 and p-MLKL was down-regulated ( P<0.05), and the damage to the ultrastructure of hippocampal neurons was sinificantly reduced in CPB+ Sev group ( P<0.05). Conclusions:The mechanism by which sevoflurane preconditioning attenuates cognitive impairment may be related to the inhibition of calcium overload-mediated hippocampal necroptosis in a rat model of CPB.

Objective:To evaluate the mediating effect of electrocardiographic (ECG) indicators in the association between short-term exposure to fine particulate matter (PM 2.5) and blood pressure and to explore the key PM 2.5 element constituents that produce the mediating effect. Methods:Based on a cross-sectional survey across 10 cities in the Beijing-Tianjin-Hebei region and surrounding areas, PM 2.5 and its element constituents were collected from the nearest air monitoring superstation. Blood pressure and ECG indicators of participants were obtained through physical examinations. A multivariate linear regression was used to evaluate the effect of short-term exposures to PM 2.5 on blood pressure. A mediation analysis was used to identify the mediating effect of ECG indicators in the association between exposure to PM 2.5 and its element constituents and blood pressure. Results:The age of the 1 793 participants was (65.1±13.3) years, and 885 (49.4%) were males. During the study period, the daily mean concentration of PM 2.5 was (70±45) μg/m 3, and the systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and pulse pressure (PP) were (139±20), (82±11), (101±13), and (57±17) mmHg (1 mmHg=0.133 kPa), respectively. The results of the multivariate linear regression showed that for every 10 μg/m 3 increase in PM 2.5 on the same day (lag 0), DBP increased by 0.15 (95% CI: 0.02-0.28) mmHg, and PP decreased 0.18 (95% CI: 0.36-0.01) mmHg. The exposure to 14 elemental constituents, such as Ga, Co and Se, was associated with an increase in DBP, while the exposure to 17 elemental constituents, such as Cs, Se and Ag, was associated with a decrease in PP. At lag 0, the PM 2.5-induced increase in DBP was mediated by the QRS interval (mediation percentage of 18.98%), and the PM 2.5-induced decrease in PP was mediated by the QT interval (mediation percentage of -6.31%). The exposure to K, Br, Pb, Zn, Ca, Co, Pd, Cu, and As constituents was associated with increases in DBP mediated by prolonged QRS interval. The exposure to Pb, Zn, K, and As constituents was associated with decreases in PP mediated by prolonged QRS interval. Conclusion:ECG indicators such as QRS interval may mediate the association between short-term exposure to PM 2.5 and its element constituents and blood pressure.

Objective:To assess the effect of short-term exposures to atmospheric fine particulate matter (PM 2.5) and its components on cognitive function in middle-aged and older people aged 40-89 and identify key components that affect cognitive function. Methods:From October 2018 to March 2019, a cross-sectional survey of middle-aged and older people aged 40-89 was conducted across 10 cities in Beijing-Tianjin-Hebei and neighboring regions of China. Data on PM 2.5 and its components were collected from the nearest air supermonitoring stations to the residential addresses. The cognitive function was assessed using the Min-Mental State Examination (MMSE) scale. Multiple linear regression models were used to assess the effect of short-term exposures to PM 2.5 and its components on cognitive function in middle-aged and older people. The restricted cubic spline function was used to fit the exposure-response relationship between different components and changes in MMSE scores. Results:The age of the 1 978 respondents was (65.1±13.4) years, and 976 (49.34%) were males. During the study period, the daily mean concentration of PM 2.5 was (71.2±43.2) μg/m 3, and the MMSE score was (28.2±3.7). The results of the multiple linear regression model showed that short-term exposures to PM 2.5 and its components were associated with cognitive decline in middle-aged and older people after adjusting for confounding factors, and the effect was higher at lag 0-28 days. For an interquartile range (64.3 μg/m 3) increase in PM 2.5 at lag 0-28 d, the MMSE score decreased by 5.91 (95% CI: 0.04, 11.77). For an interquartile range increase in organic carbon (OC), antimony (Sb), chromium (Cr), zinc (Zn), tin (Sn), and cadmium (Cd), the MMSE scores of middle-aged and older people decreased by 5.71 (95% CI: 1.69, 9.73), 4.67 (95% CI: 2.50, 6.84), 4.49 (95% CI: 1.05, 7.92), 3.65 (95% CI: 0.89, 6.42), 2.76 (95% CI: 1.22, 4.30), and 1.72 (95% CI: 0.53, 2.92). Conclusions:Short-term exposures to atmospheric PM 2.5 and its components (OC, Sb, Cr, Zn, Sn, and Cd) are associated with cognitive decline in middle-aged and older people.

OBJECTIVE To investigate the current status of contamination with carbapenem-resistant gram-negative bacteria in environment of intensive care units(ICU)of tertiary hospitals in Shanghai and find out the potential contamination sources so as to provide bases for prevention and control of multidrug-resistant organisms infec-tions in the ICUs.METHODS The surroundings of the ICU patients detected with CRGNB and environmental ob-jects surfaces in public area were sampled by mSuperCARBA chromogenic media from Dec.2024 to Jan.2025,the strains were isolated,and the targeted strains were identified by matrix-assisted laser desorption/ionization time-of-flight(MALDI-TOF)mass spectrometer.RESULTS A total of 653 samples were collected in the survey,76 of which were positive for bacterial culture,60 were detected with CRGNB,and the isolation rate of CRGNB was 9.19％.The isolation rate of CRGNB was 53.40％in the water-source group,0.91％in the non-water-source group,and there was significant difference(x2=286.450,P＜0.001).The result of whole genome sequencing for 17 strains of CRKP showed that ST11 and ST15 were the two major types of multilocus typing(MT),respective-ly carrying 2-12 types of drug resistance genes.CONCLUSIONS The CRGNB strains are detected in some environ-mental sites of the ICUs of 15 tertiary hospitals in Shanghai,and the isolation rate of CRKP is highest among them.The colonization rate of CRGNB is relatively low on the highly frequent-contact object surfaces of the ICUs,however,sink drain holes poses a risk of hospital-acquired CRGNB infections transmissions.Additionally,the ba-sins and towels of the CRGNB patients are hard to be thoroughly cleaned,disinfected and dried,resulting in a high contamination rate.

Objective:To investigate the role of telomere length in the causal effects of immune-mediated diseases on liver fibrosis.Methods:Genome-wide association study (GWAS) data were extracted from open GWAS (https: //gwas.mrcieu.ac.uk) for a two-sample Mendelian randomization (MR) analysis. Five immune-mediated autoimmune diseases (rheumatoid arthritis, systemic lupus erythematosus, primary biliary cirrhosis, primary biliary cholangitis, and Crohn′s disease) individually and collectively were included as exposure factors, telomere length as a mediator, and liver fibrosis as the outcome. The Wald ratio and inverse variance weighted (IVW) methods were performed to assess causal effects. The MR-Egger intercept test was adopted to evaluate the level of horizontal pleiotropy. Multivariable MR was employed to quantify the proportion of the effect of immune-mediated diseases on liver fibrosis mediated by telomere length. And sensitivity analyses were performed to assess the robustness of the results.Results:The results of IVW analysis revealed that the overall category of immune-mediated diseases, rheumatoid arthritis, systemic lupus erythematosus, primary biliary cirrhosis, primary biliary cholangitis, and Crohn′s disease were causally related to the high risk of liver fibrosis, and the OR were 1.63 (95% confidence intervals (95% CI): 1.33 to 2.10), 1.28 (95% CI: 1.14 to 1.43), 1.34 (95% CI: 1.02 to 1.74), 1.36 (95% CI: 1.27 to 1.47), 1.37 (95% CI: 1.23 to 1.52), and 1.52 (95% CI: 1.15 to 2.01), respectively ( P<0.001, <0.001, =0.032, <0.001, <0.001, =0.003). Horizontal pleiotropy was detected in the association between Crohn′s disease and liver fibrosis (MR-Egger intercept test, P=0.025).The results of multivariable MR indicated that telomere length acted as a mediating factor in the causal relationship between liver fibrosis and the overall category of immune-mediated diseases, rheumatoid arthritis, systemic lupus erythematosus, primary biliary cholangitis ( OR=2.24, 95% CI: 1.41 to 3.56; OR=1.78, 95% CI: 1.03 to 3.06; OR=2.11, 95% CI: 1.31 to 3.40; OR=2.01, 95% CI: 1.06 to 3.80; P<0.001, =0.038, =0.002, =0.032, respectively ). Conclusion:The causal effects of the overall category of immune-mediated diseases, rheumatoid arthritis, systemic lupus erythematosus, and primary biliary cholangitis on liver fibrosis are mediated by telomere length.

Objective To investigate the perioperative use of antimicrobial agents in class Ⅰ incisional ophthalmic surgeries in secondary first-class and above medical institutions in Shanghai City,and provide a basis for the rational use of antimicrobial agents in such surgeries.Methods Perioperative antimicrobial prophylaxis(PAP)in patients undergoing class Ⅰ incisional ophthalmic surgery reported by secondary first-class and above hospitals in Shanghai City from 2017 to 2022 was collected retrospectively.The prophylactic use rate,types,rationality of selection,and timing of use of antimicrobial agents were analyzed comprehensively.Results From 2017 to 2022,a total of 54 868 cases of class Ⅰ incisional ophthalmic surgeries were reported from secondary first-class and above hospitals in Shanghai City.The PAP rates in tertiary comprehensive hospitals,tertiary specialty hospitals,tertiary traditional Chinese medicine hospitals,and secondary comprehensive hospitals were 4.72％,1.79％,3.22％,and 6.63％,re-spectively.The overall PAP rate showed a yearly decreasing trend,from 6.39％in 2017 to 2.31％in 2021.Among different types of hospitals,the PAP rate in secondary comprehensive hospitals decreased most significantly,from 12.72％in 2017 to 0.53％in 2022.The main types of prophylactic antimicrobial use were first-,second-and third-generation cephalosporins,and quinolones.The rational selection rates of antimicrobial agents were highest in ter-tiary comprehensive hospitals(17.13％)and lowest in tertiary specialty hospitals(1.08％).The PAP rates in sys-temic veins 0.5-1 hour before surgery were highest in tertiary specialty hospitals(88.17％)and lowest in tertiary comprehensive hospitals(71.53％).The withdrawal rates of antimicrobial agents within 24 hours after surgery were highest in tertiary traditional Chinese medicine hospitals(80.87％)and lowest in tertiary specialty hospitals(13.26％).Conclusion The PAP for class Ⅰ incisional ophthalmic surgeries in secondary first-class and above medical institutions in Shanghai City still presents certain irrational phenomena in terms of antimicrobial types and administration routes.The administration rate 0.5-1 hour before surgery and withdrawal rate of antimicrobial agents within 24 hours after surgery need to be further improved.Enhanced management is necessary to promote more rational use of antimicrobial agents.

Objective To explore and analyze the characteristics and transmission routes of carbapenem-resistant Klebsiella pneumoniae(CRKP)strains in intensive care unit(ICU).Methods From January to October 2023,17 clinical infection isolates(clinical infection group),5 active screening isolates(active screening group),and 7 envi-ronmental isolates(environmental group)of CRKP in the liver surgery ICU of a hospital were selected and analyzed by whole-genome sequencing.The differences in resistance genes,virulence genes,and sequence typing(ST)were compared,and transmission routes were analyzed based on the phylogenetic tree.Results 29 strains of CRKP car-ried 4-18 resistance genes and 52-98 virulence genes,respectively.There were no statistically significant diffe-rences in genotype distribution of resistance genes,the number of virulence genes,and gene types among three groups of CRKP(all P＞0.05).ST showed that 29 CRKP strains mainly consisted of two categories:ST11 and ST15.Based on the phylogenetic tree constructed from the core genome,there were 7 highly homologous groups of CRKP,among which 4 groups had clear epidemiological associations.Conclusion CRKP in ICU carries more re-sistance and virulence genes,and some strains are highly homologous in ST and phylogenetic tree,which may lead to cross transmission.In the future,prevention and control measures should be strengthened to reduce the trans-mission of CRKP.

Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 ? by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Ⅰa-loop-helix Ⅰβ motif which cor-responds to helix Ⅰ of other P450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,the γ-domain.The structure reveals a homodimer in which the γ-domain of one molecule interacts with the β-domain of another.The plane of heme group makes an angle of ap-proximately 40° with the helix Ⅰa-loop-helix Ⅰβ motif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recogni-tion.Phe-301,Ser-303 and Gly-305 from the helix Ⅰa-loop-helix Ⅰβ motif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.