Objective To explore the value of phase contrast(PC)MRI intracranial hemodynamic parameters for predicting acute mountain sickness(AMS).Methods Totally 72 healthy young volunteers were prospectively recruited.Intracranial hemodynamic parameters of internal carotid artery(ICA)and internal jugular vein(IJV)were measured using PC MRI under normal breathing,as well as mild,moderate and severe Valsalva maneuvers(VM)in plain area.The subjects were divided into AMS group(n=9)and non-AMS group(n=63)according to results of Lake Louise score(LLS)10 h after a rapid ascent to plateau area with altitude of 4 411 m.Univariate and multivariate logistic regression analyses were performed to screen independent predictors of AMS under different states and then construct single and combined VM states prediction models.Receiver operating characteristic curves were plotted,and the area under the curve(AUC)was calculated to evaluate the predictive efficacy of each model.Results ICA pulsatility index(PIICA)under mild VM,IJV cross-sectional area(SIJV)under moderate VM and IJV resistance index(RIIJV)under severe VM were all independent predictors of AMS(all P＜0.05).The efficacy of combined VM states model(AUC=0.869)for predicting AMS was higher than each single VM state model(AUC=0.698-0.738).Conclusion The model constructed based on PIICA under mild VM,SIJV under moderate VM and RIIJV under severe VM could be used to effectively predict AMS.

Objective To explore the value of phase contrast(PC)MRI intracranial hemodynamic parameters for predicting acute mountain sickness(AMS).Methods Totally 72 healthy young volunteers were prospectively recruited.Intracranial hemodynamic parameters of internal carotid artery(ICA)and internal jugular vein(IJV)were measured using PC MRI under normal breathing,as well as mild,moderate and severe Valsalva maneuvers(VM)in plain area.The subjects were divided into AMS group(n=9)and non-AMS group(n=63)according to results of Lake Louise score(LLS)10 h after a rapid ascent to plateau area with altitude of 4 411 m.Univariate and multivariate logistic regression analyses were performed to screen independent predictors of AMS under different states and then construct single and combined VM states prediction models.Receiver operating characteristic curves were plotted,and the area under the curve(AUC)was calculated to evaluate the predictive efficacy of each model.Results ICA pulsatility index(PIICA)under mild VM,IJV cross-sectional area(SIJV)under moderate VM and IJV resistance index(RIIJV)under severe VM were all independent predictors of AMS(all P＜0.05).The efficacy of combined VM states model(AUC=0.869)for predicting AMS was higher than each single VM state model(AUC=0.698-0.738).Conclusion The model constructed based on PIICA under mild VM,SIJV under moderate VM and RIIJV under severe VM could be used to effectively predict AMS.

Objective: To retrospectively analyze the epidemic characteristics and spatial distribution of vomiting and diarrhea outbreaks in schools and kindergartens in Shanghai from 2015 to 2019, so as to provide the scientific evidence for optimizing prevention and control of vomiting and diarrhea outbreaks in schools and kindergartens. Methods: Data collection and analysis were carried out on the vomiting and diarrhea outbreaks reported to Shanghai Municipal Center for Disease Control and Prevention from 2015 to 2019. Epidemiological characteristics were analyzed and compared. The proportion and incidence of outbreaks in schools and kindergartens were calculated, and the influencing factors of outbreaks were analyzed by multivariate Logistic regression. The index of Moran s I was used for the global and local spatial auto correlation analysis. Results: Among the 344 vomiting and diarrhea outbreaks, 98.26% occurred in kindergartens, primary schools, middle schools and other educational institutions. The median number of cases per outbreak was 15. The number of suspected outbreaks and the percentage of cases involved peaked in 2015 ( 60.00% , 84.35%) and then decreased year by year to 16.00% and 38.80% in 2019. About 86.98% of the outbreaks were transmitted by human to human contact. Among the 329 outbreaks with samples collected from cases and/or environments, the main pathogen detected was norovirus ( n =280), and sapovirus was detected in outbreak for the first time in 2016. The outbreaks showed obvious seasonality, with two peaks (November, March) and one trough (July), and the majority of outbreaks occurred in primary schools (44.38%) and kindergartens (32.84%). Compared with kindergartens, the probabilities of suspected epidemic outbreaks in primary schools, combined schools, middle schools and other educational institutions were higher (adjusted OR =6.40, 9.16, 12.64 , 5.58, P <0.01). The proportion and incidence of outbreaks in educational institutions in different districts showed no high-high aggregation areas. Conclusions Primary schools and kindergartens are key places for the prevention and control of vomiting and diarrhea outbreaks. Targeted prevention and control measures should be strengthened at the beginning of each semester and before the peak of the epidemic each year. Timely reporting of symptoms, suspension of school admissions after symptoms appear and standardized disposal of vomit are effective measures to reduce interpersonal transmission and control the scale of an outbreak.

ObjectiveTo investigate the changes in the pathogen spectrum of viral diarrhea in local pediatric inpatients as well as any variations in genotypes of major pathogens during the COVID-19 control period. MethodsFecal samples were collected from the children <5 years who were hospitalized due to acute gastroenteritis in a pediatric hospital in Shanghai. PCR test was carried out to detect rotavirus， norovirus， sapovirus， astrovirus and enteric adenovirus， and then genotyping was performed for major pathogens. ResultsOut of 546 samples， 37.55% tested positive for virus with the following positive rate ranking： norovirus GⅡ （22.16%）， group A rotavirus （16.12%）， astrovirus （2.93%）， enteric adenovirus （2.38%）， sapovirus （0.92%） and norovirus GⅠ （0.18%）. The predominant genotype within norovirus GⅡ were GⅡ.4［P31］ and GⅡ.4［P16］ with a proportion of 24.79% and 14.05% respectively. The detection rate of GⅡ.4［P31］ dropped significantly over the 2-year period （χ²＝16.140，P<0.001）. In addition， an emerging rotavirus genotype G8P ［8］， which was rarely found nationally， was discovered for the first time locally with an increasing proportion， accounting for 7.95% of all rotavirus positive cases. Phylogenic analysis demonstrated that the representative strains of this genotype were genetically closer to the DS-1-like G8P ［8］ strain found in Southeast Asia. ConclusionThe changes in the prevalence of various norovirus genotypes together with the emergence of rare rotavirus genotype in the local area illustrate the importance of continuous monitoring of viral diarrhea and genotyping of key pathogens. Increased local activity of the rare genotype also adds new parameters in the efficacy evaluation of marketed vaccines and development of potential new vaccines in near future.

ObjectiveTo present the exploration and application of a prospective follow-up research method for acute infectious disease surveillance based on natural community populations， using COVID-19 infection as an example， and to provide a reference for improving the infectious disease surveillance and early warning system. MethodsA multi-stage probability proportional sampling method was employed to sample residents from all communities of 16 administrative districts in Shanghai， with households as the units. A cohort for acute infectious diseases based on natural community populations was established. The baseline survey was conducted for all cohort subjects， and COVID-19 antigen test kits were distributed. From December 21， 2022 to September 30， 2023， prospective follow-up monitoring of COVID-19 antigen and nucleic acid was carried out on the study subjects on a weekly basis. The baseline characteristics and follow-up information of the cohort subjects were described. ResultsThe cohort for acute infectious diseases included a total of 12 881 subjects， comprising 6 098 males （47.3%） and 6 783 females （52.7%）. The baseline survey revealed that 35.2% （4 540/12 881） of the subjects had a history of COVID-19 infection. During the follow-up period from December 21， 2022 to September 30， 2023， the average incidence density in the cohort was 0.61/person-year， with a higher incidence density in females （0.63/person-year） compared to males （0.59/person-year）. Individuals aged 60 and above （0.64/person-year） and those with underlying health conditions （0.67/person-year） had a higher incidence density. Healthcare workers showed a notably higher incidence density （0.84/person-year） than that in other occupational groups. As of September 30， 2023， a total of 340 subjects in the cohort experienced secondary infections， with a median interval of 170 days between the first and second infections. ConclusionThis study applies cohort study method to acute infectious disease surveillance， providing crucial data support for estimating infection rates and forecasting alerts for acute infectious diseases in the community. This method can be promoted and applied as a new approach for acute infectious disease surveillance.

Objective The oxidative damage of DNA can be caused by excessive levels of Reactive oxygen species(ROS).Monitoring of DNA oxidative damage enables effective evaluation of ROS damage effects.Although the detection of DNA damage effects based on microbial sensor allows quantitative analysis of oxidative damage,the ROS clearance mechanism existed in bacterial will affect the sensitive of detection.The work of this article is to knockout the key genes of ROS clearance mechanism and construct an antioxidant gene-knock-out microbial sensor.The microbial sensor can realize sensitive monitoring of DNA damage effects and then evaluates the damage effects of cells by ROS.Methods The antioxidant damage genes of bacterial ahpCF,katE and katG were knocked out by λ-Red homologous recombination and antioxidant gene-knockout microbial sensor was constructed.The nalidixic acid sodium salt and UV irradiation were used to characterize the performance for monitoring of DNA damage effects.Results The antioxidant gene-knockout microbial sensors ΔahpC,ΔahpCF/ΔkatEG and ΔahpCF/ΔkatE/ΔkatG were constructed successfully.The results showed that the microbial sensor ΔahpCF/ΔkatE/ΔkatGl had the highest sensitive of damage effects and the limit of detection for nalidixic acid sodium salt was 0.40 μmol/L.In addition,1.80 min of UV irradiation(254 nm)was sufficient to induce a significant fluorescent expression effect in the engineered bacteria.Conclusion In this article,antioxidant gene-knockout microbial sensors had been constructed to realize active and sensitive monitoring of DNA damage effects such as DNA damage reagents and UV irradiation.The sensors could provide an active,effective,and sensitive potential monitoring method for future evaluation of radiation effects in space.

Objective To investigate the role of sea-level cerebral blood flow(CBF)in predicting acute mountain sickness(AMS)using three-dimensional pseudo-continuous arterial spin labeling(3D-pCASL). Methods Forty-eight healthy volunteers reached an altitude of 3,650 m by air after undergoing a head magnetic resonance imaging(MRI)including 3D-pCASL at sea level.The CBF values of the bilateral anterior cerebral artery(ACA),middle cerebral artery(MCA),posterior cerebral artery(PCA),and posterior inferior cerebellar artery(PICA)territories and the laterality index(LI)of CBF were compared between the AMS and non-AMS groups.Statistical analyses were performed to determine the relationship between CBF and AMS,and the predictive performance was assessed using receiver operating characteristic(ROC)curves. Results The mean cortical CBF in women(81.65±2.69 mL/100 g/min)was higher than that in men(74.35±2.12 mL/100 g/min)(P<0.05).In men,the cortical CBF values in the bilateral ACA,PCA,PICA,and right MCA were higher in patients with AMS than in those without.Cortical CBF in the right PCA best predicted AMS(AUC=0.818).In women,the LI of CBF in the ACA was different between the AMS and non-AMS groups and predicted AMS with an AUC of 0.753. Conclusion Although the mechanism and prediction of AMS are quite complicated,higher cortical CBF at sea level,especially the CBF of the posterior circulatory system,may be used for prediction in male volunteers using non-invasive 3D-pCASL.

Objective:To understand the epidemiological characteristics of diarrheagenic Escherichia ( E. ) coli infection in infectious diarrhea outpatients aged 15 years and older in Shanghai and provide evidence for the development of disease control strategies .Methods:Based on multistage systematic sampling, diarrhea surveillance was conducted in 22 sentinel hospitals in Shanghai, the information about cases' demographic, clinical, and epidemiological characteristics were collected. Stool samples were collected for the detection and typing of diarrheagenic E. coli by local centers for disease control and prevention. The positive rate of diarrheagenic E. coli in different populations and seasons from 2014 to 2021 were analyzed. Statistical analysis was conducted by using χ2 test. Results:In 15 185 diarrhea cases, 8.05% (1 222/15 185) were positive for diarrheagenic E. coli. The positive rate was higher in men (8.74%, 684/7 824) than in women (7.31%, 538/7 361). The positive rate was highest in age group 15-29 years (9.14%, 335/3 665) and the annual positive rate was highest in 2021 (10.21%, 83/813), the differences were all significant ( P<0.05). In the 1 264 strains of diarrheagenic E. coli analyzed through PCR, enterotoxingenic E. coli was the most frequently identified pathogen (50.24%, 635/1 264), followed by enteroadhesive E. coli (27.93%, 353/1 264), and enteropathogenic E. coli (21.36%, 270/1 264). The positive rate of diarrheagenic E. coli showed obvious seasonality with peak in summer (13.92%, 774/5 562) ( χ2=495.73, P<0.001). Conclusions:Diarrheagenic E. coli has become a prominent pathogen in infectious diarrhea cases in Shanghai, the disease can occur all the year round with incidence peak during summer and autumn. Predominant subtypes included enterotoxingenic E. coli, enteroadhesive E. coli and enteropathogenic E. coli. Targeted prevention and control strategies are needed for diarrheagenic E. coli-induced infectious diarrhea in different age groups, seasons and for different types of infections.

Objective:To investigate the changes in symptoms of inflammatory bowel disease (IBD) patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the coronavirus disease 2019 (COVID-19) pandemic, as well as the situation of IBD treatment medication use.Methods:A cross-sectional survey study method was used. A questionnaire survey was conducted on a voluntary sampling basis for IBD patients of multiple centers nationwide from December 1st to 31st 2022, collecting clinical data of patients diagnosed with COVID-19 through nucleic acid/antigen testing. Patients were divided into symptomatic exacerbation group and asymptomatic exacerbation group based on whether they felt an exacerbation of IBD symptoms including abdominal discomfort, increased bloody stool or the appearance of purulent bloody stool, increased frequency of diarrhea, etc. And the differences in age, gender, body mass index (BMI) , underlying disease conditions, SARS-CoV-2 vaccination status, IBD type, disease activity, COVID-19 symptoms, and treatment medication between the two groups were compared.Results:A total of 497 patients were included, 317 males and 180 females; age (35.27±11.54) years; 355 CD patients and 142 UC patients; more than 50% of patients exhibited respiratory system symptoms such as fever, muscle soreness, fatigue, cough, expectoration, nasal congestion, and some IBD patients exhibited digestive system symptoms and nervous system symptoms. The symptomatic exacerbation group consisted of 104 patients (20.93%) , and the asymptomatic exacerbation group consisted of 393 (79.07%) . There were no statistically significant differences in gender, age, BMI, underlying diseases, IBD type, and SARS-CoV-2 vaccine doses between the two groups (all P>0.05) . Compared with the asymptomatic exacerbation group, the proportion of patients in the disease active phase was higher [47.12% (49/104) vs. 24.68% (97/393) , P<0.001], and the proportion of patients using mesalazine/sulfasalazine was higher (35.58% vs. 23.41%, P = 0.012) , and the proportions of COVID-19 symptoms such as diarrhea, headache, and dizziness were all higher (all P<0.05) in the symptomatic exacerbation group. Among the 237 IBD patients using biologics, there was a statistically significant difference in the types of biologics used between the symptomatic and asymptomatic exacerbation groups (χ 2 = 9.351, P = 0.031) . Among the 240 patients using biologics, the proportion of delaying or interrupting the use of biologics was higher in symptomatic exacerbation group than that of the asymptomatic exacerbation group, and the difference was statistically significant [45.45% (20/44) vs. 23.98% (47/196) , χ 2 = 8.235, P = 0.004]. Among the 47 patients using immunosuppressants, there was no statistically significant difference in the proportion of stopping immunosuppressants between the symptomatic and asymptomatic exacerbation groups ( P = 0.263) . Conclusion:The main symptoms of IBD patients infected with COVID-19 are respiratory and systemic symptoms, and those in the active phase of the disease or those delaying or withdrawing biologics are more likely to experience an exacerbation of IBD symptoms during the infection.

Objective:To investigate the changes in symptoms of inflammatory bowel disease (IBD) patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the coronavirus disease 2019 (COVID-19) pandemic, as well as the situation of IBD treatment medication use.Methods:A cross-sectional survey study method was used. A questionnaire survey was conducted on a voluntary sampling basis for IBD patients of multiple centers nationwide from December 1st to 31st 2022, collecting clinical data of patients diagnosed with COVID-19 through nucleic acid/antigen testing. Patients were divided into symptomatic exacerbation group and asymptomatic exacerbation group based on whether they felt an exacerbation of IBD symptoms including abdominal discomfort, increased bloody stool or the appearance of purulent bloody stool, increased frequency of diarrhea, etc. And the differences in age, gender, body mass index (BMI) , underlying disease conditions, SARS-CoV-2 vaccination status, IBD type, disease activity, COVID-19 symptoms, and treatment medication between the two groups were compared.Results:A total of 497 patients were included, 317 males and 180 females; age (35.27±11.54) years; 355 CD patients and 142 UC patients; more than 50% of patients exhibited respiratory system symptoms such as fever, muscle soreness, fatigue, cough, expectoration, nasal congestion, and some IBD patients exhibited digestive system symptoms and nervous system symptoms. The symptomatic exacerbation group consisted of 104 patients (20.93%) , and the asymptomatic exacerbation group consisted of 393 (79.07%) . There were no statistically significant differences in gender, age, BMI, underlying diseases, IBD type, and SARS-CoV-2 vaccine doses between the two groups (all P>0.05) . Compared with the asymptomatic exacerbation group, the proportion of patients in the disease active phase was higher [47.12% (49/104) vs. 24.68% (97/393) , P<0.001], and the proportion of patients using mesalazine/sulfasalazine was higher (35.58% vs. 23.41%, P = 0.012) , and the proportions of COVID-19 symptoms such as diarrhea, headache, and dizziness were all higher (all P<0.05) in the symptomatic exacerbation group. Among the 237 IBD patients using biologics, there was a statistically significant difference in the types of biologics used between the symptomatic and asymptomatic exacerbation groups (χ 2 = 9.351, P = 0.031) . Among the 240 patients using biologics, the proportion of delaying or interrupting the use of biologics was higher in symptomatic exacerbation group than that of the asymptomatic exacerbation group, and the difference was statistically significant [45.45% (20/44) vs. 23.98% (47/196) , χ 2 = 8.235, P = 0.004]. Among the 47 patients using immunosuppressants, there was no statistically significant difference in the proportion of stopping immunosuppressants between the symptomatic and asymptomatic exacerbation groups ( P = 0.263) . Conclusion:The main symptoms of IBD patients infected with COVID-19 are respiratory and systemic symptoms, and those in the active phase of the disease or those delaying or withdrawing biologics are more likely to experience an exacerbation of IBD symptoms during the infection.