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.

BACKGROUND:Studies have shown that platelet-derived growth factor BB can stimulate the proliferation and osteogenic differentiation of mesenchymal stem cells and accelerate the calcification process of osteoblast-like cells.However,its clinical application has problems such as short half-life and easy decomposition.Loading the growth factor onto a suitable biomaterial scaffold can enable its slow and continuous release and maintain an effective concentration,which has become a hot topic in current research.OBJECTIVE:To observe the effect of chitosan/reduced graphene oxide scaffolds loaded with platelet-derived growth factor BB on the repair of alveolar bone defect in rats.METHODS:(1)Chitosan/reduced graphene oxide scaffolds(referred to as CS/rGO scaffolds)and chitosan/reduced graphene oxide scaffolds loaded with different mass concentrations(5,10,15,and 20 mg/L)of platelet-derived growth factor BB(referred to as CS/rGO/PDGF-BB-5,CS/rGO/PDGF-BB-10,CS/rGO/PDGF-BB-15,and CS/rGO/PDGF-BB-20 scaffolds)were prepared respectively.The five groups of scaffolds were co-cultured with rat periodontal ligament stem cells.The cell proliferation and migration were detected by CCK-8 assay and Transwell chamber assay,respectively,to screen the appropriate growth factor loading mass concentration for subsequent experiments.CS/rGO scaffolds(or extracts)and CS/rGO/PDGF-BB-15 scaffolds(or extracts)were co-cultured with rat periodontal ligament stem cells,and the osteogenic differentiation and angiogenic ability of the cells were detected.(2)The alveolar bone defect model was prepared in front of the bilateral maxillary first molars of 16 SD rats,and the rats were randomly divided into 4 intervention groups:the blank control group did not receive any intervention,the simple scaffold group was implanted with CS/rGO/PDGF-BB-15 scaffold,the control group was implanted with CS/rGO scaffold and rat periodontal ligament stem cell complex,and the experimental group was implanted with CS/rGO/PDGF-BB-15 scaffold and rat periodontal ligament stem cell complex,with 4 rats in each group.Twelve weeks after surgery,the bone repair of the alveolar bone defect was observed by Micro CT scanning and hematoxylin-eosin staining.RESULTS AND CONCLUSION:(1)CS/rGO/PDGF-BB-5,CS/rGO/PDGF-BB-10,CS/rGO/PDGF-BB-15,and CS/rGO/PDGF-BB-20 scaffolds could promote the proliferation and migration of rat periodontal ligament stem cells.Among them,the CS/rGO/PDGF-BB-15 scaffold had the most significant effect on promoting cell proliferation and migration,and this scaffold was used for subsequent experiments.Compared with the CS/rGO scaffold,the CS/rGO/PDGF-BB-15 scaffold could promote the osteogenic and angiogenic differentiation of rat periodontal ligament stem cells.(2)Micro CT scanning and hematoxylin-eosin staining results showed that the experimental group had the best alveolar bone defect repair effect,and a large amount of new bone tissue and blood vessel formation could be seen.(3)The chitosan/reduced graphene oxide scaffold loaded with platelet-derived growth factor BB can effectively promote the repair of rat alveolar bone defects by promoting the proliferation,migration,angiogenic and osteogenic differentiation of rat periodontal ligament stem cells.

BACKGROUND:Studies have shown that platelet-derived growth factor BB can stimulate the proliferation and osteogenic differentiation of mesenchymal stem cells and accelerate the calcification process of osteoblast-like cells.However,its clinical application has problems such as short half-life and easy decomposition.Loading the growth factor onto a suitable biomaterial scaffold can enable its slow and continuous release and maintain an effective concentration,which has become a hot topic in current research.OBJECTIVE:To observe the effect of chitosan/reduced graphene oxide scaffolds loaded with platelet-derived growth factor BB on the repair of alveolar bone defect in rats.METHODS:(1)Chitosan/reduced graphene oxide scaffolds(referred to as CS/rGO scaffolds)and chitosan/reduced graphene oxide scaffolds loaded with different mass concentrations(5,10,15,and 20 mg/L)of platelet-derived growth factor BB(referred to as CS/rGO/PDGF-BB-5,CS/rGO/PDGF-BB-10,CS/rGO/PDGF-BB-15,and CS/rGO/PDGF-BB-20 scaffolds)were prepared respectively.The five groups of scaffolds were co-cultured with rat periodontal ligament stem cells.The cell proliferation and migration were detected by CCK-8 assay and Transwell chamber assay,respectively,to screen the appropriate growth factor loading mass concentration for subsequent experiments.CS/rGO scaffolds(or extracts)and CS/rGO/PDGF-BB-15 scaffolds(or extracts)were co-cultured with rat periodontal ligament stem cells,and the osteogenic differentiation and angiogenic ability of the cells were detected.(2)The alveolar bone defect model was prepared in front of the bilateral maxillary first molars of 16 SD rats,and the rats were randomly divided into 4 intervention groups:the blank control group did not receive any intervention,the simple scaffold group was implanted with CS/rGO/PDGF-BB-15 scaffold,the control group was implanted with CS/rGO scaffold and rat periodontal ligament stem cell complex,and the experimental group was implanted with CS/rGO/PDGF-BB-15 scaffold and rat periodontal ligament stem cell complex,with 4 rats in each group.Twelve weeks after surgery,the bone repair of the alveolar bone defect was observed by Micro CT scanning and hematoxylin-eosin staining.RESULTS AND CONCLUSION:(1)CS/rGO/PDGF-BB-5,CS/rGO/PDGF-BB-10,CS/rGO/PDGF-BB-15,and CS/rGO/PDGF-BB-20 scaffolds could promote the proliferation and migration of rat periodontal ligament stem cells.Among them,the CS/rGO/PDGF-BB-15 scaffold had the most significant effect on promoting cell proliferation and migration,and this scaffold was used for subsequent experiments.Compared with the CS/rGO scaffold,the CS/rGO/PDGF-BB-15 scaffold could promote the osteogenic and angiogenic differentiation of rat periodontal ligament stem cells.(2)Micro CT scanning and hematoxylin-eosin staining results showed that the experimental group had the best alveolar bone defect repair effect,and a large amount of new bone tissue and blood vessel formation could be seen.(3)The chitosan/reduced graphene oxide scaffold loaded with platelet-derived growth factor BB can effectively promote the repair of rat alveolar bone defects by promoting the proliferation,migration,angiogenic and osteogenic differentiation of rat periodontal ligament stem cells.

The concept of "spirit" in traditional Chinese medicine （TCM） aligns closely with "the liver governs the designing of strategy". By exploring the relationship between the liver and executive function decline， it is proposed that prolonged liver constraint leads to indecisiveness in strategy designing， which is the initiating factor for executive function decline； liver blood deficiency causes difficulties in executing strategy， which forms an essential foundation for the progression of executive function decline； obstruction in the "liver-du mai-brain" pathway leads to unclear strategy designing， which accelerates executive function decline. This relationship is examined from the perspectives of TCM， modern medicine， and cognitive psychology， aiming to provide insights into addressing executive function decline through treatments focused on the liver.

This case report describes a 68-year-old male patient diagnosed with primary hepatocellular carcinoma (HCC). After receiving Yttrium-90 microsphere selective internal radiation therapy (⁹⁰Y-SIRT), the tumor significantly reduced in size, and tumor markers alpha fetoprotein (AFP) and abnormal prothrombin (PIVKA-Ⅱ) decreased. Postoperative pathological results showed minimal residual tumor cells, indicating that ⁹⁰Y-SIRT has good efficacy and safety in downstaging and conversion of HCC, thereby facilitating subsequent surgical resection.

The pathogenesis of tinnitus is unclear and may involve the peripheral and central nervous sys-tems.Recent studies have found that neuroinflammatory response leads to hyperactivity of nerve center,in which tumor necrosis factor-α(TNF-α)has an important impact on neurotransmitter transmission,transmembrane ion concentration,neuronal synaptic structure and functional reorganisation,and may play an important role in the path-ogenesis of acute tinnitus.This article discusses the central mechanism of TNF-α in mediating the onset of acute tin-nitus.

Objective To evaluate the efficacy and safety of recombinant staphylokinase in patients with acute ST-segment elevation myocardial infarction(STEMI)by a multi-center,randomized,position-controlled,parallel post-marketing clinical trial.Methods This study was a multi-center,randomized,positive drug parallel control,non-inferiority clinical trial.From July 2019 to June 2022,a total of 251 patients with STEMI were enrolled in 31 hospitals.Patients were randomly assigned to receive intravenous staphylokinase or alteplase in a ratio of 1∶1.Vascular recanalization was evaluated by clinical indicators 30 minutes,60 minutes and 120 minutes after the initiation of thrombolysis.Coronary angiography was performed 90 to 120 minutes after the initiation of thrombolysis.The proportion of infarct-related artery(IRA)with thrombolysis in myocardial infarction(TIMI)grade Ⅱ and Ⅲ,corrected TIMI frame count(CTFC)and TIMI myocardial perfusion grade(TMPG)were analyzed Major adverse cardiac events(MACE,including all-cause death,rehospitalization,reinfarction,urgent target vessel revascularization)and bleeding events were followed up at 30 days(±2 days)after thrombolysis.Results After excluding 7 subjects who did not use thrombolytic drugs,244 subjects were finally eligibled from 31 hospitals(117 in trial group and 127 in control group),and 232 subjects completed the follow-up(111 in trial group and 121 in control group).The vascular recanalization rate evaluated by clinical indicators at 120 minutes after thrombolysis was 85.6％ in trial group and 83.5％ in control group(P=0.657).The difference between the two groups was 2.11(95％CI-7.19-11.41).Given that the lower confidence limit of the 95％CI was greater than-12％,the non-inferiority of the vascular recanalization rate was established based on clinical judgment.Coronary angiography showed that the total patency rate of IRA(TIMIⅡ-Ⅲ)was 77.5％ in trial group and 77.7％ in control group(P=0.970).The difference between the two groups was-0.21(95％CI-10.95-10.54),with the lower bound of the 95％CI exceeding-12％.Therefore,the non-inferiority of the TIMI blood flow grade was confirmed,indicating that the total patency rate of IRA in the trial group was not inferior to that in the control group.The CTFC was(32.7±17.6)frames in trial group and(37.6±16.6)frames in control group,with no statistically significant difference between the two groups(P=0.054).The difference between the two groups was-4.9(95％CI-10.0-0.1).As the lower limit of the 95％CI exceeded-12％,the noninferiority of CTFC was successfully demonstrated.The proportions of TMPG 0-Ⅲ were 20.7％,6.3％,2.7％and 69.4％in trial group,and 22.3％,4.1％,6.6％ and 66.9％ in control group,respectively.There was no significant difference in TIMI myocardial perfusion grade between the two groups(P=0.086).The incidence of MACE was 7.7％ in trial group and 7.1％ in control group within 30 days after the initiation of thrombolysis,and there was no significant difference between the two groups(P=0.857).Further analysis showed that there was no significant difference in cardiovascular mortality(3.4％ vs.4.7％,P=0.751).All 244 subjects were included in the safety analysis set.There was no significant difference in the total incidence of bleeding events between the two groups(22.2％ vs.15.0％,P=0.144).There was no significant difference in the incidence of major bleeding(1.7％ vs.0.8％,P=0.609).Conclusions Recombinant staphylokinase is simple to use and has a rapid onset of action.The efficacy and safety of recombinant staphylokinase are not inferior to alteplase in the treatment of acute STEMI.

Objective To analyze the preferences of elderly cancer patients for internet hospital diagnosis and treatment services,providing a reference for the sustainable development of internet hospitals.Methods This study was based on the method of discrete choice experiments.By combining literature review and expert consultation,10 relevant attributes affecting the choice of internet hospitals by elderly cancer patients were determined.Through KANO questionnaires,6 key attributes were se-lected to form the final DCE questionnaire,consisting of 11 choice sets and 1"quality control"set.Using the convenience sam-pling method,elderly cancer patients visiting a certain tertiary hospital in Tianjin were selected to collect 318 valid question-naires.The obtained data were analyzed using mixed Logit regression.Results Patients visiting a certain specialized cancer hos-pital in Tianjin tend to prefer hospitals with a grade of Grade Ⅲ-A(β=0.661 6,P＜0.05)and those offering out-of-hospital rehabilitation guidance for cancer patients(β=0.559 9,P＜0.05).The page operation process(β=0.352 2,P＜0.05)and the accessibility mode for the elderly(β=0.357 5,P＜0.05)are the attributes with lower attention.In the subgroup analysis,for patients of different genders and different family incomes,hospital grade and out-of-hospital rehabilitation guidance for cancer patients remain the most influential factors,but male patients pay more attention to the page operation process(β=0.378 3,P＜0.05)and the accessibility mode for the elderly(β=0.373 7,P＜0.05),while female patients pay more attention to the cover-age of medical insurance reimbursement(β=0.435 9,P＜0.05),which has a greater impact than that of male patients(β=0.394 7,P＜0.05);patients with a monthly per capita income of less than 5 000 yuan pay more attention to the coverage of medical insurance reimbursement(β=0.423 0,P＜0.05)and the self-appointment check function(β=0.467 0,P＜0.05);while patients with a monthly per capita income of more than 5 000 yuan pay more attention to the page operation process(β=0.364 7,P＜0.05)and the accessibility mode for the elderly(β=0.359 1,P＜0.05).Conclusion Hospitals should en-hance elderly patients' awareness and trust in internet hospitals by providing comprehensive health education and support,simpli-fying operational processes,strengthening age-friendly design,and highlighting medical insurance coverage to address the diverse needs across genders and income levels.

Lentiviral vectors(LVs)are key gene delivery tools for integrating target genes into the host genome,but they may also pose risks of insertional mutagenesis.The vector copy number(VCN)in cells is critical for determining the safety of gene modification.However,the reliability and accuracy of its quantification process are influenced by multiple factors.Developing cell reference materials with specific vector copy numbers represents a viable approach to enhance the reliability and consistency of measurement results,enabling quality control of the quantification process and traceability of outcomes.However,the preparation of such reference materials faces challenges in cell sample design,preparation protocols,and advanced quantification techniques.In this study,T lymphocyte cell line Jurkat-based reference materials with LV gene copy numbers of 1 and 2 copy/cell were developed.A high-precision duplex digital polymerase chain reaction(dPCR)method was established to quantify the LV gene and endogenous genes simultaneously.Additionally,the results of dPCR were cross-validated through next-generation sequencing and flow cytometric analysis.Ultimately,confocal microscopy characterization results showed that the developed cell reference materials had intact morphology.The quantification result of VCN-1 was(1.07±0.11)copy/cell,and that of VCN-2 was(2.09±0.21)copy/cell.These cell reference materials demonstrated compliance with stability and homogeneity requirements,and could be applied for quality control throughout the VCN measurement workflow and metrological traceability,improving the accuracy,comparability,and validity of copy number measurements.

Obesity represents a complex, heritable condition shaped by interactions among genetic, epigenetic, metagenomic, and environmental factors. Nevertheless, the mechanistic contributions of genetic variation and epigenetic regulation to obesity pathogenesis remain incompletely elucidated. Advances in molecular profiling technologies have enabled the identification of numerous biomarkers associated with childhood obesity phenotypes. These discoveries facilitate understanding of obesity etiology and its links to chronic diseases. This review synthesizes current research on genomic and epigenomic biomarkers influencing childhood obesity susceptibility, advances our comprehension of etiological heterogeneity and intervention strategies, and offers conceptual frameworks for precision prevention based on epigenetic mechanisms.