Clinical death refers to the permanent cessation of life functions. This article reviews the definition of clinical death and the various scenarios in which it occurs, classifies the process of clinical death, and discusses the criteria for determining uncontrollable cardiac death, controllable cardiac death and the criteria and workflow for determining brain death. It elaborates on the relationship between brain death and death, and proposes the areas to note when standardizing the medical documentation of death cases. Based on this, it introduces the content of the management system and workflow construction for death determination in medical institutions, including management structure, personnel qualifications, document norms, quality control system and training mechanism. Paying attention to the construction of the management system and workflow for death determination in medical institutions is of great significance for ensuring medical quality and safety, promoting the healthy development of organ donation, and maintaining the seriousness of legal and ethical practices.

Metabolic associated fatty liver disease （MAFLD） is the most prevalent chronic liver disease worldwide， and its progression is closely associated with the development of liver fibrosis， liver cirrhosis， and even hepatocellular carcinoma. However， there is still a lack of effective therapies for MAFLD in clinical practice. Telomere is the protective structure at the end of chromosomes， and telomere shortening and functional impairment have been identified as one of the key factors regulating the pathological progression of MAFLD. This article systematically reviews the core mechanism of action of telomere regulation in MAFLD， including its molecular functions in nucleotide metabolism， oxidative stress， and epigenetic regulation， as well as its pathological effect in hepatocytes and hepatic stellate cells. In addition， this article explores the clinical prospects of telomeres as biomarkers and therapeutic targets for MAFLD， in order to provide a theoretical reference for improving the precise diagnosis and treatment system of MAFLD.

Objective:To evaluate the efficacy and safety of nebulized inhalation of recombinant human interferon (IFN) α1b injection in the treatment of respiratory syncytial virus (RSV) associated lower respiratory tract infections (pneumonia and bronchiolitis) in children.Methods:A randomized, double-blind, parallel, placebo-controlled add-on design was used.Children with pneumonia or bronchiolitis aged 2 months to 5 years who tested positive for RSV antigen within 72 hours of onset from 30 clinical trial sites including Beijing Children′s Hospital, Capital Medical University between February 2021 and December 2022 were included in this study and randomly divided into 2 groups at a ratio of 1∶1 based on a stratified-block method.Both groups received basic treatments such as cough control, asthma relieving, expectorant treatment, fever reduction, oxygen therapy, etc.The experimental group received additional nebulized inhalation of IFN α1b injection at a dose of 2.0 μg/(kg·time), twice a day.The control group received nebulized inhalation of placebo twice a day.Clinical efficacy was evaluated based on indicators such as the duration of clinical symptoms and signs, and the Kaplan-Meier method was used to calculate the median and 95% CI of the duration of clinical symptoms and signs.The Log-rank test was used to compared data between groups.Safety was assessed through the incidence of adverse reactions and laboratory tests, and the Chi-square test was used to analyze the difference between groups. Results:There were 123 children in the experimental group and 122 children in the control group.The median durations of all the 5 clinical symptoms and signs [including shortness of breath, wheezing, dyspnea (visible retractions), decreased transcutaneous oxygen saturation, and abnormal mental state] in the experimental group after treatment were slightly shortened than those in the control group [2.7 d(95% CI: 1.9-3.0 d)] vs.[2.9 d(95% CI: 2.6-3.6 d), P=0.027].The improvement in dyspnea (retractions) was especially pronounced in the experimental group, with a relief rate of 50.0% (0, 100%) on the first day of administration[compared with 0 (0, 50.0%) in the control group ( Z=2.002, P=0.025)].The median duration of dyspnea in the experimental group was nearly 1 day shorter than that in the control group [1.0 d(95% CI: 0.7-1.7 d) vs.1.8 d(95% CI: 1.0-2.5 d), P=0.046].There were no significant difference in hospital stay [6.0(5.0, 8.0) d vs.6.5(5.0, 8.0) d, Z=0.675, P=0.500], oxygen therapy duration [32.0(14.0, 96.3) h vs.39.0 (24.0, 83.2) h, Z=0.094, P=0.925], the recovery rate from clinical symptoms during treatment [(105/106, 99.1%) vs.(96/101, 95.0%)], and recurrence rate [(0/106, 0) vs.(2/101, 2.0%)] between the 2 groups (all P>0.05).However, the above-mentioned four indicators in the experimental group showed a trend of clinical benefits.The quantitative virus detection results showed that the RSV viral load in both groups decreased after treatment compared to before treatment.After 2 days of treatment, the decline rate of RSV viral load from the baseline was 0.90 lg copies/(mL·d) in the experimental group and 0.25 lg copies/(mL·d)in the control group, with a statistically significant difference ( P<0.05).Furthermore, there was no statistically significant difference in the incidence of adverse reactions between the 2 groups ( P>0.05).Importantly, no drug-related serious adverse reactions occurred in both groups. Conclusions:The nebulized inhalation therapy of IFN α1b demonstrates efficacy and safety in treating pediatric RSV associated lower respiratory tract infections.It particularly offers outstanding clinical therapeutic value for severe children.

Objective:To construct a sizeable naive human Fab phage display antibody library to screen high-affinity specific antibodies in vitro. Methods:Total RNA was extracted from peripheral blood mononuclear cells (PBMCs) of 126 healthy individuals, subsequently reverse-transcribed into cDNA, and used as a template. PCR amplification was performed to obtain the V H from IgG, IgM and light chain κ, λ, separately, with the initial PCR products serving as templates for a second round of PCR. Overlap extension PCR was employed to generate fragments of the κ and λ light chains. These fragments were ligated with the phage vector pNC3, which harbors the variable region 1 of the heavy chain, to construct a recombinant phage plasmid. This plasmid was then electroporated into competent Escherichia Coli TG1 cells to establish a naive human Fab phage display antibody library. One hundred clones were randomly selected for identification and sequencing, and antibody gene polymorphisms were analyzed using the IMGT database and MAFFT software. Recombinant α-hemolysin from Staphylococcus aureus was utilized to screen Fab antibody fragments through biopanning of the antibody library, followed by random selection of phage ELISA-identified clones. The positive clones (antigen A450∶blank control A450≥2.1) were sequenced. Results:Two large naive Fab phage display antibody libraries were successfully constructed, in which the capacity of κ and λ chain antibody libraries were 1.25×10 11 and 1.54×10 11, respectively. The titers for two antibody libraries were 6.04×10 13 CFU/ml and 3.50×10 13 CFU/ml. The positive transformation insertion rates for κ and λ chain antibody libraries were 96% (96/100) and 100% (100/100), respectively. Sequence analysis revealed that all antibody sequences were unique. The amino acid sequences in the skeletal region were relatively conserved. In contrast, significant variations in the length of the complementarity determining region (CDR) were found, and the diversity of amino acid sequence of the complementary determining region was high, especially the CDR3. Analysis using the IMGT database indicated that the sequences exhibited a broad distribution across variable-diversity-joining gene families. After six rounds of panning, specific phage antibodies enrichment targeting α-hemolysin were achieved. A total of 142 monoclonal antibodies were sequenced, yielding 8 distinct Fab antibody sequences. Conclusion:This study successfully constructed two naive human Fab phage display antibody libraries with large capacity and good diversity, which can be used for screening human antibodies for serum epidemiology.

Objective:To analyze the epidemiological characteristics and trend of hospitalization of the patients with herpes zoster in Beijing from 2017 to 2022.Methods:In this retrospective study, the information of hospitalization of herpes zoster patients were collected from all medical institutions at the first level and above in Xicheng, Changping, and Miyun districts of Beijing. The age and gender specific hospitalization rates and age-standardized hospitalization rates were calculated. Joinpoint regression model was used to explore the trend of the hospitalization rates, and the influencing factors of the hospital stay length and complications were analyzed.Results:The age-standardized hospitalization rate of the patients with herpes zoster was 10.82/100 000-18.43/100 000 in Beijing from 2017 to 2022 [annual percent change (APC) =5.86%, 95% CI: -2.80%-15.98%]. The age-standardized hospitalization rate of the cases with herpes zoster as the main diagnosis showed an upward trend (APC=11.35%, 95% CI: 7.21%-16.23%). The age-standardized hospitalization rate showed an upward trend in women (APC=14.34%, 95% CI: 7.95%-22.37%). The hospitalization rate showed a downward trend in age group 30-39 years (APC=-24.92%, 95% CI: -48.56% - -1.85%) and showed upward trends in age group 70-79 years and 80-109 years (APC=23.18%, 95% CI: 13.53%-35.58%; APC=4.90%, 95% CI: 1.18%-9.19%). Complications occurred in 66.28% (680/1 026) of the patients. The median hospital stay length was 9 (5,15) days, and the patients with high age (≥80 years) and two or more complications had longer hospital stay, which were 12 (6, 23) and 14 (7, 27) days respectively ( P<0.001). Conclusions:The hospitalization rate in women and the elderly aged ≥70 years with herpes zoster as the main diagnosis showed upward trends in Beijing in recent years. The elderly aged ≥80 years usually had longer hospital stay, showing a relatively disease burden level. More attention should be paid to development of intervention strategies, such as vaccine, for this population.

Aim To systematically analyze the risk factors for comorbid ischemic cardiovascular and cerebrovas-cular diseases using principal component analysis.It seeks to identify key risk factors influencing comorbidity and to con-struct a predictive model to serve as a screening tool for the prevention and management of comorbidities.Methods This retrospective study included patients diagnosed with coronary artery disease from December 1,2009 to June 30,2020,at the First Affiliated Hospital of Xinjiang Medical University,using data from the hospital's integrated coronary heart dis-ease prevention platform.Patients were divided into two groups:those with both cardiovascular and cerebrovascular disea-ses and those with only coronary artery disease based on inclusion and exclusion criteria.Clinical indicators during hospi-tal admission were collected.The sample was randomly divided into a modeling set and a validation set in a 7∶3 ratio.In the modeling set,principal component analysis was used to explore the distribution differences in risk factors between the comorbid group and the single-disease group.By analyzing factor load contributions,the most significant variables were i-dentified.Logistic regression was then used to construct a predictive model,and a nomogram was generated.The model's predictive ability and robustness were evaluated in the validation set.Results A total of 11 808 participants were included,with 2 781(23.6%)in the comorbid group and 9 027(76.4%)in the coronary heart disease-only group.Compared with the single-disease group,the comorbid group had a higher average age,a greater proportion of females,and higher systolic blood pressure levels at admission(P<0.001).Additionally,thelevelsof hemoglobin,platelet distri-bution width,low density lipoprotein,and blood sodium were significantly higher in the comorbid group(P<0.05).A total of 8 265 participants were randomly assigned to the modeling set.Principal component analysis identified seven key factors with factor load contributions greater than 5:sodium level,systolic blood pressure,diastolic blood pressure,age,hemoglobin concentration,platelet distribution width,and total bilirubin level.Using these factors,a nomogram was con-structed via Logistic regression.The nomogram's area under the receiver operating characteristic curve for predicting co-morbid ischemic cardiovascular and cerebrovascular diseases was 0.630(95%CI:0.600～0.768,P<0.001).A total of 3 543 participants were randomly assigned to the validation set.In the validation set,the receiver operating characteristic curve was 0.628.Conclusion Elevated sodium level,higher systolic and diastolic blood pressure at admission,older age,increased hemoglobin concentration,higher platelet distribution width,and lower total bilirubin level are risk factors for comorbid ischemic cardiovascular and cerebrovascular diseases.The nomogram constructed has clinical value for screening patients with such comorbidities.

Objective:To understand the incidence rate of herpes zoster (HZ) and postherpetic neuralgia (PHN) in Beijing, and analyze the incidence trend of HZ and PHN from 2015 to 2022.Methods:Cases of HZ and PHN from 2015 to 2022 were retrieved from the Hospital Information Systems (HIS) of all primary and above hospitals/clinics in three districts representing the urban, inner suburban, and outer suburban areas of Beijing. After duplication screening, the first visit cases were screened, and the incidence characteristics were described. The incidence rate of HZ and PHN in each year by sex and age group and the age-standardized incidence rate were calculated. The annual percentage increase (APC) of incidence rate was calculated using the Joint regression model, and the change trend was analyzed.Results:The age-standardized incidence rate of HZ in Beijing from 2015 to 2022 ranged from 7.44‰ to 10.05‰, with an average annual incidence rate of 8.95 ‰, significantly increasing with age ( P<0.001). The Joinpoint regression model showed that the overall age-standardized incidence of HZ remained relatively stable, with no significant difference (APC=2.28%, t=1.56, P=0.170). However, the incidence rate among the 0-19-year-old group exhibited a trend of decrease (APC=-10.70%, t=-6.29, P<0.001). For PHN, the age-standardized incidence in Beijing ranged from 0.77‰ to 2.67‰, with an average annual incidence rate of 1.59‰ and a proportion of 9.48% to 26.86% among HZ cases. Both the incidence of PHN and its proportion among HZ cases increased with age ( P<0.001). The age-standardized incidence of PHN increased annually (APC=18.56%, t=9.02, P<0.001). Conclusion:The incidence rate of HZ and PHN in Beijing continues to be at a high level, and PHN shows an increasing trend over time.

Mandibular reconstruction refers to the restoration of the continuity of the mandible through techniques such as autologous bone grafting,thereby restoring the patient's basic appearance,reconstructing the occlusal relationship,and restoring functions such as opening the mouth,chewing,and swallowing,in order to achieve a unity of oral and maxillofacial forms and functions.Due to the fact that mastication necessitates the coordinated efforts of the masticatory muscles,mandible,dental arch,and tongue,the recovery of masticatory function not only serves as a robust indicator for the success of surgery but also enhances the patients'quality of life,facilitating an early return to normal life.Currently,for the rehabilitation of oral function in patients after mandibular reconstruction surgery,standardized tools have been established in the fields of swallowing,occlusion,and speech assessment,and targeted training has been implemented,yielding significant therapeutic outcomes.However,research related to masticatory function faces two major challenges.First,existing assessment tools primarily focus on a single dimension,such as masticatory efficiency or subjective perception,and an integrated assessment system that encompasses multiple dimensions,including bite force distribution and oral sensory perception,has not yet been established.Second,although individual studies have explored factors affecting postoperative masticatory function,a systematic consensus has not been veached,leading to a lack of precision and individualization in clinical interventions,which significantly prolongs the patients'rehabilitation period.This paper reviews the scope and limitations of existing assessment tools for masticatory function in patients after mandibular reconstruction and systematically analyzes the key factors affecting postoperative masticatory function,aiming to promote a shift in clinical practice from"structural reconstruction"to a"function-perception collaborative rehabilitation"approach,and to provide a theoretical framework for constructing evidence-based,personalized masticatory rehabilitation programs.

Objectives:This study aims to evaluate the causal relationship between plasma proteins and myocardial infarction(MI)using two-sample bidirectional Mendelian randomization(MR)analysis,identify key biomarkers,and validate their expression.Methods:The study utilized publicly available genome-wide association study(GWAS)data of 4 907 plasma proteins as the exposure factor,with single nucleotide polymorphisms(SNPs)as instrumental variables,and four MI datasets as outcomes.Two-sample MR analysis was performed using the inverse variance weighted(IVW)method,complemented by simple model,weighted model,weighted median estimator(WME),and MR-Egger regression methods to assess the causal relationship between exposure factors and outcomes.Venn diagrams and word clouds were used to screen proteins associated with MI as candidate biomarkers.Reverse MR analysis was conducted to evaluate reverse causality.Sensitivity analysis was performed to assess the robustness of the results.Immunohistochemistry(IHC)was used to validate the expression of proteasome activator subunit 1(PSME1)and vacuolar protein sorting 29(VPS29)in the aorta of mice,and enzyme-linked immunosorbent assay(ELISA)was used to verify the expression of PSME1 and VPS29 in plasma from patients with acute myocardial infarction(AMI).Results:The two-sample MR analysis indicated that PSME1 was significantly negatively associated with myocardial infarction in all four datasets,with OR(95%CI)of 0.684(0.557-0.839),0.990(0.987-0.993),0.579(0.448-0.748),and 0.993(0.990-0.996),respectively,with all P<0.001.Similarly,VPS29 also showed a significant negative association with MI in all four datasets,with OR(95%CI)of 0.902(0.862-0.945),0.998(0.997-0.999),0.866(0.808-0.929),and 0.998(0.997-0.999),respectively,with all P<0.001.Reverse MR analysis did not detect reverse causality,and sensitivity analysis confirmed the robustness of the results.IHC results showed significantly reduced expression of PSME1 and VPS29 in the aortas of AMI mice with an atherosclerotic background compared to control mice(both P<0.05).ELISA results indicated significantly lower plasma levels of PSME1 and VPS29 in AMI patients compared to healthy controls(both P<0.05).Conclusions:Higher levels of PSME1 and VPS29 are negatively associated with the risk of MI,suggesting that PSME1 and VPS29 may serve as protective biomarkers for cardiovascular diseases.

Objectives:This study aims to evaluate the causal relationship between plasma proteins and myocardial infarction(MI)using two-sample bidirectional Mendelian randomization(MR)analysis,identify key biomarkers,and validate their expression.Methods:The study utilized publicly available genome-wide association study(GWAS)data of 4 907 plasma proteins as the exposure factor,with single nucleotide polymorphisms(SNPs)as instrumental variables,and four MI datasets as outcomes.Two-sample MR analysis was performed using the inverse variance weighted(IVW)method,complemented by simple model,weighted model,weighted median estimator(WME),and MR-Egger regression methods to assess the causal relationship between exposure factors and outcomes.Venn diagrams and word clouds were used to screen proteins associated with MI as candidate biomarkers.Reverse MR analysis was conducted to evaluate reverse causality.Sensitivity analysis was performed to assess the robustness of the results.Immunohistochemistry(IHC)was used to validate the expression of proteasome activator subunit 1(PSME1)and vacuolar protein sorting 29(VPS29)in the aorta of mice,and enzyme-linked immunosorbent assay(ELISA)was used to verify the expression of PSME1 and VPS29 in plasma from patients with acute myocardial infarction(AMI).Results:The two-sample MR analysis indicated that PSME1 was significantly negatively associated with myocardial infarction in all four datasets,with OR(95%CI)of 0.684(0.557-0.839),0.990(0.987-0.993),0.579(0.448-0.748),and 0.993(0.990-0.996),respectively,with all P<0.001.Similarly,VPS29 also showed a significant negative association with MI in all four datasets,with OR(95%CI)of 0.902(0.862-0.945),0.998(0.997-0.999),0.866(0.808-0.929),and 0.998(0.997-0.999),respectively,with all P<0.001.Reverse MR analysis did not detect reverse causality,and sensitivity analysis confirmed the robustness of the results.IHC results showed significantly reduced expression of PSME1 and VPS29 in the aortas of AMI mice with an atherosclerotic background compared to control mice(both P<0.05).ELISA results indicated significantly lower plasma levels of PSME1 and VPS29 in AMI patients compared to healthy controls(both P<0.05).Conclusions:Higher levels of PSME1 and VPS29 are negatively associated with the risk of MI,suggesting that PSME1 and VPS29 may serve as protective biomarkers for cardiovascular diseases.