ObjectiveTo analyze the epidemiological characteristics and influencing factors of SARS-CoV-2 reinfection by conducting follow-up investigations among community residents who experienced their first SARS-CoV-2 infection between March and June 2022, so as to provide a scientific basis for predicting future epidemic trends and adjusting prevention and control strategies. MethodsA cohort study was conducted in Xuhui District, Shanghai. A total of 1 208 individuals with a documented primary SARS-CoV-2 infection between March and June 2022 were enrolled and followed-up longitudinally. Data were collected using structured questionnaire surveys to assess the reinfection rate, incidence density, and clinical manifestations of SARS-CoV-2 reinfection. A logistic regression model was used to analyze the influencing factors of SARS-CoV-2 reinfection. ResultsA total of 497 SARS-CoV-2 reinfection cases were observed among the 1 208 research subjects, with a reinfection rate of 41.14% and an incidence density of 0.63 cases per 1 000 person-days. The cumulative reinfection rates at 6, 9, 12, 15, and 18 months following the initial infection were 0.08%, 15.31%, 19.04%, 33.53%, and 38.25%, respectively. Compared with the primary infection, reinfection was more likely to be symptomatic, with a greater severity of fever, dry cough, sore throat, and runny nose. Being female, younger age, and symptom duration ≥7 days during the primary infection were identified as influencing factors for SARS-CoV-2 reinfection, while a higher socioeconomic status can reduce the risk of SARS-CoV-2 reinfection. ConclusionSARS-CoV-2 reinfection is relatively common and often symptomatic. Age, gender, income level, and the duration of symptoms during the primary infection are identified as infuencing factors for SARS-CoV-2 reinfection. Continuous monitoring of reinfection in the population is recommended, along with the development of effective strategies to mitigate the impact of reinfection.

ObjectiveTo analyze the epidemiological characteristics of long COVID and to investigate its main influencing factors by examining individuals infected with SARS-CoV-2 between March and June 2022 in two communities in Shanghai, to lay the foundation for further research on the mechanism and clinical treatment of long COVID, and to provide the basis for the development of inexpensive, convenient, and feasible prevention and intervention strategies. MethodsA cross-sectional study was conducted, enrolling 6 410 individuals infected with SARS-CoV-2. Data were collected through a questionnaire survey. The incidence and common symptoms of long COVID were analyzed, along with their associations with demographic characteristics, medical history, and behavioral factors. A logistic regression model was used to identify the major factors associated with the development of long COVID symptoms. ResultsThe overall incidence rate of long COVID among the study population was 13.9%. The most commonly reported symptoms included fatigue (65.1%), attention disorders (23.1%), and cough (16.9%). The analysis showed that having underlying chronic diseases (OR=2.580, 95%CI: 2.165‒3.074), a history of allergies (OR=1.418, 95%CI: 1.003‒1.971), current smoking (OR=1.461, 95%CI: 1.013‒2.079), ever smoking (OR=2.462, 95%CI: 1.687‒3.551), a greater number of symptoms during the acute phase [1 symptom (OR=1.778, 95%CI: 1.459‒2.162), 2 symptoms (OR=2.749, 95%CI: 2.209‒3.409), ≥3 symptoms (OR=7.792, 95%CI: 6.333‒9.593)] and aggravated symptoms during the acute phase (OR=1.082, 95%CI: 1.070‒1.094) were factors associated with a higher risk of developing long COVID symptoms. Additionally, individuals who had consumed alcohol in the past year (OR=1.914, 95%CI: 1.344‒2.684) were more prone to objective long COVID symptoms. Among individuals under 50 years of age, females (OR=1.427, 95%CI: 1.052‒1.943) were more likely to develop objective long COVID symptoms. ConclusionThis study has identified the diversity of long COVID symptoms, which involve multiple organs and systems, including fatigue, attention disorders, cough, and joint pain. It has also revealed associations between long COVID and various demographic factors (e.g., age, gender), personal medical history (e.g., underlying chronic diseases, history of allergies), acute-phase characteristics (e.g., number and severity of symptoms), and behavioral factors (e.g., smoking, alcohol consumption). These findings highlight the need for further research and ongoing surveillance of long COVID and may inform the development of more targeted health management strategies for specific populations.

BACKGROUND:Epidemiologic investigations and some experiments have shown that there is a close relationship between peripheral blood cells and osteoporosis,but the causal relationship between the two at the genetic level is still unclear. OBJECTIVE:To explore the causal relationship between peripheral blood cells and osteoporosis using Mendelian randomization methods. METHODS:Genome-wide association study data sets on peripheral blood cells,overall bone density at different ages,and calcaneal bone density were obtained from databases such as Blood Cell Consortium and MRC Integrative Epidemiology Unit. Blood cells were used as exposure data,with bone density at different ages and calcaneal bone density serving as outcome data. Mendelian randomization analyses were performed using methods such as inverse variance weighting,MR-Egger,weighted median method,and simple median. The results were assessed for heterogeneity,pleiotropy,and sensitivity using Cochran's Q,MR-Egger regression,and Leave-one-out method. The causal relationship between exposure and outcomes was evaluated using β values. RESULTS AND CONCLUSION:Due to the heterogeneity revealed by Cochran's Q test in the Mendelian randomization results,the results of the study were based on the inverse variance weighting method. The inverse variance weighting results showed that when age-specific bone density was used as an outcome,there was a negative causal relationship between white blood cell count and whole-body bone mineral density at the age of 45-60 years[β=-0.07,95％ confidence interval (CI):-0.13,-0.01,P=0.02],a positive causal relationship between monocyte count and whole-body bone mineral density at the age of 45-60 years (β=0.05,95％ CI:0.00,0.10,P=0.037),a negative causal relationship between white blood cell and basophil counts and whole-body bone mineral density over 60 years old (β=-0.04,95％ CI:-0.07,-0.01,P=0.005;β=-0.04,95％ CI:-0.07,-0.00,P=0.038),a positive causal relationship between hemoglobin concentration and hematocrit and whole-body bone mineral density over 60 years old (β=0.04,95％ CI:0.01,0.08,P=0.012;β=0.04,95％ CI:0.00,0.07,P=0.039),and a negative causal relationship between white cell count and whole-body bone mineral density at an undistinguished age (β=-0.10,95％ CI:-0.16,-0.03,P=0.002). When heel bone mineral density was used as an outcome,there was a negative causal relationship between white cell count and heel bone mineral density (β=-0.04,95％ CI:-0.07,-0.01,P=0.016),and a positive causal relationship between hemoglobin concentration and hematocrit and heel bone mineral density (β=0.05,95％ CI:0.01,0.08,P=0.007;β=0.05,95％ CI:0.01,0.08,P=0.004). To ensure the robustness of the results,meta-analyses of Mendelian randomization results of peripheral blood cells and whole-body bone mineral density as well as heel bone mineral density in different age groups were conducted. The results suggested that for every standard deviation decrease in log-transformed white blood cell count,there was a 5％ reduction in the risk of decreased bone mineral density (OR=0.95,95％ CI:0.94,0.97,P<0.001);whereas for every standard deviation increase in hemoglobin concentration and hematocrit,there was a 4％ reduction in the risk of decreased bone density (OR=1.04,95％ CI:1.03,1.06,P<0.001). In conclusion,increased white blood cell count in peripheral blood is a risk factor for bone mineral density;whereas increased hematocrit and hemoglobin concentration are protective factors for bone mineral density.

Objective To investigate the role of miR-185-5p expression changes in inducing myo-cardial metabolic abnormalities mediated by inflammatory responses in patients with chronic heart failure(CHF).Methods A total of 228 CHF patients treated in our department from June 2022 to June 2024 were prospectively enrolled and served as observation group,and another 108 healthy individuals taking physical examinations were subjected as the control group.Cardioechography was used to detect ejection time,fractional shortening,stroke volume,left ventricular mass index(LVMI),left ventricular end-diastolic diameter(LVEDD),left ventricular ejection fraction(LVEF),and left ventricular end-systolic diameter(LVESD).Then LV circumferential end-systolic wall stress(CESS)and MEE were calculated.The levels of IL-6,CRP,and TNF-α were detected with ELISA.Results The expression of miR-185-5p was significantly lower,and the levels of IL-6,CRP,and TNF-α were obviously higher in the observation group than the control group(P＜0.01).MiR-185-5p was negatively correlated with IL-6,CRP and TNF-α levels(r=-0.765,-0.558,-0.693,P＜0.01);MEE was negatively correlated with miR-185-5p(r=-0.594,P＜0.01)and positively with IL-6,CRP and TNF-α levels(r=0.712,0.684,0.559,P＜0.01).Multivariate logistic regression analysis showed that ejection time,fractional shortening,stroke volume,LVEF,and miR-185-5p were independent protective factors for MEE,while LVMI,LVESD,LVEDD,CESS,IL-6,CRP,and TNF-α were independent risk factors for MEE(P＜0.05,P＜0.01).Conclusion Low expression of miR-185-5p is associated with myocardial metabolic abnormalities mediated by inflammatory responses in CHF patients.

Objective To investigate the value of MRI of the sternal end of clavicle in bone age assessment in Chinese population,especially its applicability in the determination of criminal responsible age.Methods A total of 431 patients aged from 10.00 to 29.99 years with neck or chest MRI were retrospectively collected.According to the Schmeling grading method,the epiphyseal development of the clavicle MRI was divided into five grades.The consistency of methods was evaluated.The correlation and general descriptive analysis between MRI grades and age was analyzed.The sex difference was analyzed.Curve fitting was used to establish a nonlinear model between age and grades.Results The grades of clavicle MRI showed a significant age-related trend(Figure 2),and the correlation was 0.861(0.887 in males and 0.840 in females).Except for grade 1,there was no significant difference between males and females in other grades.The minimum age of male grade 3 was greater than 14 years old,and the minimum age of female grade 3 was greater than 16 years old.The minimum age in grade 4 and grade 5 was over 18 years old in both sexes.The best curve fitting model was cubic model for both sexes(R2=0.805 for men and 0.722 for women).Conclusion Clavicle MRI can be used for the assessment of bone age in Chinese population.Complete epiphyseal plate closure can be used as a reliable indicator for the determination of age at 18 years old,and it is expected to achieve radiation-free forensic bone age assessment.

Objective:To review and synthesize the best evidence for non-surgical offloading management in patients with diabetic foot ulcers, so as to provide reference for clinical medical staff.Methods:A literature retrieval strategy was developed to search the related articles on the management of offloading in patients with diabetic foot ulcer on the websites and databases of various guidelines.The retrieval time limit was from the establishment of the database to June 15, 2024. The quality of the literature was evaluated by two graduate students, and the evidence was extracted and synthesized.Results:A total of 15 articles were included, including 5 guidelines, 8 systematic reviews/Meta-analyses, 1 expert consensus and 1 randomized controlled trial, the best 31 pieces of evidence were obtained from 5 aspects: assessment and screening of foot ulcers, preventive offloading intervention, selection of offloading devices, other offloading techniques, and structured education.Conclusions:The evidence of non-surgical offloading management in patients with diabetic foot ulcers summarized in this study is helpful for medical and nursing professionals to provide optimal nursing and treatment outcomes for patients with diabetic foot ulcers, it also reduces the risk of infection, hospitalization and amputation.

Objective:To review and synthesize the best evidence for non-surgical offloading management in patients with diabetic foot ulcers, so as to provide reference for clinical medical staff.Methods:A literature retrieval strategy was developed to search the related articles on the management of offloading in patients with diabetic foot ulcer on the websites and databases of various guidelines.The retrieval time limit was from the establishment of the database to June 15, 2024. The quality of the literature was evaluated by two graduate students, and the evidence was extracted and synthesized.Results:A total of 15 articles were included, including 5 guidelines, 8 systematic reviews/Meta-analyses, 1 expert consensus and 1 randomized controlled trial, the best 31 pieces of evidence were obtained from 5 aspects: assessment and screening of foot ulcers, preventive offloading intervention, selection of offloading devices, other offloading techniques, and structured education.Conclusions:The evidence of non-surgical offloading management in patients with diabetic foot ulcers summarized in this study is helpful for medical and nursing professionals to provide optimal nursing and treatment outcomes for patients with diabetic foot ulcers, it also reduces the risk of infection, hospitalization and amputation.

Objective To investigate the role of miR-185-5p expression changes in inducing myo-cardial metabolic abnormalities mediated by inflammatory responses in patients with chronic heart failure(CHF).Methods A total of 228 CHF patients treated in our department from June 2022 to June 2024 were prospectively enrolled and served as observation group,and another 108 healthy individuals taking physical examinations were subjected as the control group.Cardioechography was used to detect ejection time,fractional shortening,stroke volume,left ventricular mass index(LVMI),left ventricular end-diastolic diameter(LVEDD),left ventricular ejection fraction(LVEF),and left ventricular end-systolic diameter(LVESD).Then LV circumferential end-systolic wall stress(CESS)and MEE were calculated.The levels of IL-6,CRP,and TNF-α were detected with ELISA.Results The expression of miR-185-5p was significantly lower,and the levels of IL-6,CRP,and TNF-α were obviously higher in the observation group than the control group(P＜0.01).MiR-185-5p was negatively correlated with IL-6,CRP and TNF-α levels(r=-0.765,-0.558,-0.693,P＜0.01);MEE was negatively correlated with miR-185-5p(r=-0.594,P＜0.01)and positively with IL-6,CRP and TNF-α levels(r=0.712,0.684,0.559,P＜0.01).Multivariate logistic regression analysis showed that ejection time,fractional shortening,stroke volume,LVEF,and miR-185-5p were independent protective factors for MEE,while LVMI,LVESD,LVEDD,CESS,IL-6,CRP,and TNF-α were independent risk factors for MEE(P＜0.05,P＜0.01).Conclusion Low expression of miR-185-5p is associated with myocardial metabolic abnormalities mediated by inflammatory responses in CHF patients.

BACKGROUND:Epidemiologic investigations and some experiments have shown that there is a close relationship between peripheral blood cells and osteoporosis,but the causal relationship between the two at the genetic level is still unclear. OBJECTIVE:To explore the causal relationship between peripheral blood cells and osteoporosis using Mendelian randomization methods. METHODS:Genome-wide association study data sets on peripheral blood cells,overall bone density at different ages,and calcaneal bone density were obtained from databases such as Blood Cell Consortium and MRC Integrative Epidemiology Unit. Blood cells were used as exposure data,with bone density at different ages and calcaneal bone density serving as outcome data. Mendelian randomization analyses were performed using methods such as inverse variance weighting,MR-Egger,weighted median method,and simple median. The results were assessed for heterogeneity,pleiotropy,and sensitivity using Cochran's Q,MR-Egger regression,and Leave-one-out method. The causal relationship between exposure and outcomes was evaluated using β values. RESULTS AND CONCLUSION:Due to the heterogeneity revealed by Cochran's Q test in the Mendelian randomization results,the results of the study were based on the inverse variance weighting method. The inverse variance weighting results showed that when age-specific bone density was used as an outcome,there was a negative causal relationship between white blood cell count and whole-body bone mineral density at the age of 45-60 years[β=-0.07,95％ confidence interval (CI):-0.13,-0.01,P=0.02],a positive causal relationship between monocyte count and whole-body bone mineral density at the age of 45-60 years (β=0.05,95％ CI:0.00,0.10,P=0.037),a negative causal relationship between white blood cell and basophil counts and whole-body bone mineral density over 60 years old (β=-0.04,95％ CI:-0.07,-0.01,P=0.005;β=-0.04,95％ CI:-0.07,-0.00,P=0.038),a positive causal relationship between hemoglobin concentration and hematocrit and whole-body bone mineral density over 60 years old (β=0.04,95％ CI:0.01,0.08,P=0.012;β=0.04,95％ CI:0.00,0.07,P=0.039),and a negative causal relationship between white cell count and whole-body bone mineral density at an undistinguished age (β=-0.10,95％ CI:-0.16,-0.03,P=0.002). When heel bone mineral density was used as an outcome,there was a negative causal relationship between white cell count and heel bone mineral density (β=-0.04,95％ CI:-0.07,-0.01,P=0.016),and a positive causal relationship between hemoglobin concentration and hematocrit and heel bone mineral density (β=0.05,95％ CI:0.01,0.08,P=0.007;β=0.05,95％ CI:0.01,0.08,P=0.004). To ensure the robustness of the results,meta-analyses of Mendelian randomization results of peripheral blood cells and whole-body bone mineral density as well as heel bone mineral density in different age groups were conducted. The results suggested that for every standard deviation decrease in log-transformed white blood cell count,there was a 5％ reduction in the risk of decreased bone mineral density (OR=0.95,95％ CI:0.94,0.97,P<0.001);whereas for every standard deviation increase in hemoglobin concentration and hematocrit,there was a 4％ reduction in the risk of decreased bone density (OR=1.04,95％ CI:1.03,1.06,P<0.001). In conclusion,increased white blood cell count in peripheral blood is a risk factor for bone mineral density;whereas increased hematocrit and hemoglobin concentration are protective factors for bone mineral density.

Objective To investigate the value of MRI of the sternal end of clavicle in bone age assessment in Chinese population,especially its applicability in the determination of criminal responsible age.Methods A total of 431 patients aged from 10.00 to 29.99 years with neck or chest MRI were retrospectively collected.According to the Schmeling grading method,the epiphyseal development of the clavicle MRI was divided into five grades.The consistency of methods was evaluated.The correlation and general descriptive analysis between MRI grades and age was analyzed.The sex difference was analyzed.Curve fitting was used to establish a nonlinear model between age and grades.Results The grades of clavicle MRI showed a significant age-related trend(Figure 2),and the correlation was 0.861(0.887 in males and 0.840 in females).Except for grade 1,there was no significant difference between males and females in other grades.The minimum age of male grade 3 was greater than 14 years old,and the minimum age of female grade 3 was greater than 16 years old.The minimum age in grade 4 and grade 5 was over 18 years old in both sexes.The best curve fitting model was cubic model for both sexes(R2=0.805 for men and 0.722 for women).Conclusion Clavicle MRI can be used for the assessment of bone age in Chinese population.Complete epiphyseal plate closure can be used as a reliable indicator for the determination of age at 18 years old,and it is expected to achieve radiation-free forensic bone age assessment.