Oxidative stress is an important pathophysiological pathway for the development and progression of ferroptosis. Under pathological conditions, the production of a large amount of reactive oxygen species （ROS） exceeds the buffering capacity of the antioxidant defense system, resulting in lipid peroxidation and cell ferroptosis in the state of oxidative stress. Cellular lipid peroxidation can generate toxic aldehydes, which interact with important biological macromolecules and break the normal function of cells. At present, it has been found that aldehyde dehydrogenase 2 （ALDH2） can eliminate these aldehydes and regulate the cycle of toxic aldehydes-ROS-oxidative stress-lipid peroxidation, thereby improving the prognosis of diseases associated with iron death. Ferroptosis and ALDH2 were introduced, and the current researches on ALDH2 were summarized to improve diseases associated with iron death, which can open up new directions for the subsequent research on the treatment of diseases associated with iron death.

Objective To investigate the effects of implant length,diameter,and abutment angle on bone stress distributions around maxillary central incisors,and determine the optimal parameter combination.Methods A three-dimensional(3D)model of the maxilla was reconstructed based on CBCT data.Using an orthogonal table,a total of 16 dental implant 3D models were established,varying in length,diameter,and abutment angle.These models were assembled with the maxillary and rigid-body models.Finite element analysis was performed using the transient dynamics module of ANSYS.Orthogonal experiments and one-way analysis of variance(ANOVA)were conducted on the obtained stress data.Results The implant diameter showed a statistically significant effect on the maximum von Mises stress in cortical bone(P=0.010),while implant length(P=0.229)and abutment angle(P=0.844)did not demonstrate a statistical significance.The optimal parameter combination for cortical bone stress was 5.0 mm implant diameter,12 mm implant length,and 0° abutment angle.In cancellous bone,implant length(P=0.001),diameter(P=0.011),and abutment angle(P=0.013)all had statistically significant effects on the maximum von Mises stress.The optimal parameter combination for cancellous bone stress was 14 mm implant length,5.0 mm implant diameter,and 5° abutment angle.Conclusions Implant diameter significantly affects the stress of both cortical and cancellous bone.Clinically,a larger diameter should be preferred to reduce the stress peak.Implant length is the next most important factor,while abutment angle has the least effect.

Objective To analyze the main epidemiological characteristics of fungal infection in this hospital in the past 7 years,and to provide reference for clinical treatment and prevention and control strategies of fun-gal infection.Methods The fungal data and clinical data of related patients isolated from clinical samples in Peking Union Medical College Hospital from early January 2018 to the end of May 2024 were selected,and the main epidemiological characteristics of fungal infection in this hospital were identified and described through multi-angle statistical analysis.Results A total of 4 479 patients with filamentous fungal infection were en-rolled.The proportion of male patients[57.5％(2 576/4 479)]was higher than that of female patients[42.5％(1 903/4 143)],mainly distributed in internal medicine,Intensive Care Unit(ICU)and emergency de-partment,among which internal medicine accounted for the highest proportion[50.0％(2 241/4 479)].About 90.0％of the specimens were from the lower respiratory tract,in addition to specimens from skin and soft tis-sue,tissue,ear and blood culture.In terms of seasonal distribution,there are more patients in winter.The fun-gi were mainly composed of Aspergillus,Mucor,Cerdosporium,Fusarium and Penicillium,among which As-pergillus was the most abundant,accounting for 74.6％of the total.Aspergillus fumigatus was the most a-bundant Aspergillus,accounting for 42.5％of the total Aspergillus(1 418/3 340).Among the related infec-tions caused by mold,Aspergillus was the most common in the lower respiratory tract,accounting for 76.8％.Among them,Aspergillus fumigatus accounted for the highest proportion(33.6％).98.6％of the molds infected the ear were Aspergillus,of which Aspergillus niger and Aspergillus terreus were the most common.Skin infections are mainly caused by Sporothrix schenckii,Trichophyton rubrum,Microsporum ca-nis.The results of in vitro drug sensitivity test showed that the four common Aspergillus isolated in this hos-pital were sensitive to voriconazole,and amphotericin B had better antifungal activity against Mucorales in vitro.Conclusion Based on the main epidemiological characteristics of fungal infections in this hospital,it is recommended that special attention be paid to the admission of patients in the respiratory department during the peak infection period in autumn and winter.In the treatment of fungal infections in different regions and on different body parts,attention should be paid to the differences in the distribution of bacterial species.

Objective To analyze the epidemiological characteristics of acute respiratory infections(ARIs)during the autumn-winter season in Beijing,providing evidence for the prevention,control,diagnosis,and treatment of ARIs.Methods A convenience sampling method was employed,enrolling patients who visited Peking Union Medical College Hospital(PUMCH)between September 2023 and February 2024 due to ARIs.Na-sopharyngeal swabs were collected,and real-time fluorescence quantitative PCR was used to detect six common respiratory pathogens[influenza A virus(FluA),influenza B virus(FluB),human rhinovirus(HRV),Myco-plasma pneumoniae(MP),respiratory syncytial virus(RSV),and adenovirus(ADV)],as well as SARS-CoV-2 infection.The distribution patterns of pathogen infections were analyzed.Results A total of 5556 eligible patients were included.The overall positivity rate for the six common respiratory pathogens was 63.7％,with sin-gle-pathogen positivity at 54.0％,dual-pathogen positivity at 8.9％,and triple or more pathogen positivity at 0.7％.The predominant pathogens detected were FluA(16.1％)and RSV(15.7％),followed by ADV(11.1％),MP(11.1％),HRV(10.0％),and FluB(10.0％).No significant difference in overall pathogen positivity was observed between genders.However,significant differences were found between autumn and winter(x2=34.617,P＜0.001)and among pediatric,young/middle-aged,and elderly patients(x2=422.38,P＜0.001).Specifically,MP(x2=8.647,P=0.003),FluA(x2=131.932,P＜0.001),and HRV(x2=174.199,P＜0.001)exhibited significantly higher positivity rates in autumn than in winter,whereas FluB was more prevalent in winter(x2=287.894,P＜0.001).In pediatric patients,MP,RSV,HRV,and ADV positivity rates were significantly higher than in young/middle-aged and elderly patients(all P＜0.001),whereas FluB was more common in young/middle-aged patients(both P＜0.001).The positivity rates of the six common respiratory pathogens significantly declined during the SARS-CoV-2 epidemic period,exhibiting an asynchronous seasonal pattern.Conclusions The prevalence of respiratory pathogens in Beijing is associated with age and season.Tar-geted preventive measures should be implemented in different seasons and for key populations.

Objective To investigate the effects of implant length,diameter,and abutment angle on bone stress distributions around maxillary central incisors,and determine the optimal parameter combination.Methods A three-dimensional(3D)model of the maxilla was reconstructed based on CBCT data.Using an orthogonal table,a total of 16 dental implant 3D models were established,varying in length,diameter,and abutment angle.These models were assembled with the maxillary and rigid-body models.Finite element analysis was performed using the transient dynamics module of ANSYS.Orthogonal experiments and one-way analysis of variance(ANOVA)were conducted on the obtained stress data.Results The implant diameter showed a statistically significant effect on the maximum von Mises stress in cortical bone(P=0.010),while implant length(P=0.229)and abutment angle(P=0.844)did not demonstrate a statistical significance.The optimal parameter combination for cortical bone stress was 5.0 mm implant diameter,12 mm implant length,and 0° abutment angle.In cancellous bone,implant length(P=0.001),diameter(P=0.011),and abutment angle(P=0.013)all had statistically significant effects on the maximum von Mises stress.The optimal parameter combination for cancellous bone stress was 14 mm implant length,5.0 mm implant diameter,and 5° abutment angle.Conclusions Implant diameter significantly affects the stress of both cortical and cancellous bone.Clinically,a larger diameter should be preferred to reduce the stress peak.Implant length is the next most important factor,while abutment angle has the least effect.

Nonalcoholic fatty liver disease （NAFLD） is a multisystem disease associated with obesity， insulin resistance， and dyslipidemia and has a complex pathogenesis. Studies have shown that gut microbiota dysbiosis is closely associated with the onset of NAFLD， and traditional Chinese medicine treatment can improve the laboratory markers and clinical symptoms of NAFLD patients by regulating intestinal microbiota and its metabolites. This article elaborates on the association between NAFLD and gut microbiota， the involvement of gut microbiota dysbiosis in the pathogenesis of NAFLD， and the possible mechanism of traditional Chinese medicine treatment in improving NAFLD from the perspective of gut microbiota， in order to provide new ideas for the treatment of NAFLD.

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 To explore the characteristics of blood vitamins A, B2, B6, B12, D, E, K1, K2 and folic acid and their correlation with severity in patients with metabolic-related fatty liver disease (MAFLD). Methods　From September to December 2022, a total of 473 cases of residents were recruited through community MAFLD screening activities and their health information was obtained through questionnaire survey and physical examination. The severity of hepatic steatosis was determined with FibroScan, and vitamin concentrations were determined with liquid chromatography-tandem mass spectrometry. Two independent samples' t-tests were used to assess the differences between the two groups, and univariate chi-square tests and multivariate logistic regression analysis were used to explore the related factors of MAFLD. Results　Of the 473 inhabitants, 195 (41.23%, 195/473) met the diagnostic criteria for MAFLD, including mild 43 (22.05%, 43/195) cases of fatty liver, 88 (45.13%, 88/195) cases of moderate fatty liver, and 64 (32.82%, 64/195) cases of severe fatty liver. Using healthy residents collected during the same period as controls, the overall mean of vitamins A, E, K1, and K2 in the MAFLD group was higher than that of the healthy group, with a statistical difference (P<0.05). Furthermore, the concentrations of vitamins A, E, K1 and K2 increased with the severity of fatty liver [R=0.149, P=0.004; R=0.245, P<0.001; R=0.110, P=0.032; R=0.129，P=0.012]. There were statistically significant differences (P<0.05) in the blood levels of vitamin A and E between patients with moderate or severe fatty liver and the healthy population. The blood vitamins K1 and K2 in severe fatty liver patients were also different from those of healthy people (P<0.05). However, there was no significance between folic acid, vitamin D, B2, B6, B12, and MAFLD (P>0.05). Through univariate chi-square analysis and multivariate logistic regression analysis, it was found that male [Wald=5.789, P=0.034，OR=1.598(1.037-2.463)] and vitamin E≥8.13 μg/mL[Wald=14.632，P<0.001，OR=2.378(1.522-3.674)] were risk factors for moderate and severe MAFLD. Conclusions The concentrations of vitamin A, E, and K in the blood are increased in patients with MAFLD compared to the healthy population, and they are positively correlated with the severity of MAFLD. ale gender and high levels of vitamin E may be related to moderate to severe MAFLD.

The gene encoding regulatory subunit 15 A of protein phosphatase 1 produces a protein that is a universally present protein phosphatase in eukaryotic cells.In this study,genomic DNAs were extracted from the blood of 89 Chinese Holstein cows and were used as templates for PCR amplification of the target fragment of the PPP1R15A gene.The product was tested and a polymor-phic site,E3-250T＞A was found.The polymorphism of this side and its correlation with milk pro-duction traits in Chinese Holstein cattle were statistically analyzed using SPSS 23.0 software.The findings revealed three genotypes at this site:AA,AT and TT.Cows possessing the AT and TT genotypes exhibited significant differences(P＜0.01)in milk fat and solid non-fat content com-pared to those with the AA genotype.While no significant differences were noted for other milk production traits,including milk yield,protein,lactose,somatic cell count,blood urea nitrogen,and corrected milk.The identification of functional SNPs in the PPP1R15A gene provides a theoretical basis for further research and identification of causal variations in the cow PPP1R15A gene.

To analyze the epidemiological characteristics of acute respiratory infections (ARIs) during the autumn-winter season in Beijing, providing evidence for the prevention, control, diagnosis, and treatment of ARIs.