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.

Objective To investigate the size variation in the first metatarsal of extant primates.Methods In this study,we analyzed 135 first metatarsal specimens across 12 primate genera,quantifying eight linear measurements,articular surface areas,mid-shaft cross-sectional area,total surface area,volume,and derived indices.Multivariate patterns were assessed through mean-based correspondence analysis and principal component analysis(PCA).Results Eulemur,Otolemur,Cebus,and Perodicticus exhibited a relatively high metatarsal surface-area-to-volume ratio.Perodicticus additionally showed a low articular facet index.Propithecus,Colobus,and Macaca displayed lower values for metatarsal shaft robusticity,the ratio of shaft cross-sectional area to base articular surface area,and the proximal articular facet index.Nasalis possessed a relatively high articular facet index.Pongo,Pan,Gorilla,and Homo sapiens were characterized by higher metatarsal shaft robusticity and a lower metatarsal surface-area-to-volume ratio.Principal component analysis revealed that the 12 extant primate genera could be broadly divided into two groups.Group 1 comprised Pongo,Pan,Gorilla and H.sapiens,although H.sapiens formed a distinct cluster relative to the extant great apes.Group 2 included Eulemur,Otolemur,Perodicticus,Propithecus,Cebus,Colobus,Macaca and Nasalis.Conclusion The relative sizedistribution of the first metatarsal provides some reference value for classifying extant primates.However,it demonstrates no clear correlations with specific locomotor patterns or foot grasping ability.

Objective To explore the neuroelectrophysiological mechanism of the decline of overall cognitive function and prospective memory,the syndrome manifestation of liver failing to govern conveyance and dispersion of the middle-aged and elderly people in the community with long-term emotional disturbance were evaluated.Methods Eysenck personality questionnaire(EPQ)and general condition questionnaire were used to screen the middle-aged and elderly people from 46 to 65 years old in the community who met the high and low neuroticism criteria,which were included in the long-term emotional disturbance group and the control group.According to the principle of matching sex,age(±2 years)and years of education(±2 years),60 subjects in each group were included.The scores of livers meridian syndrome,anxiety factor,depression factor and the total scores of three factors in the two groups were detected with the emotion rating scale for Ganzangxiang of traditional Chinese medicine.The overall cognitive function,the overall level of prospective memory and the dual-task paradigm of event-related memory were evaluated and event-related potential components were detected.Results Compared to the control group,the total scores of emotion rating scale for Ganzangxiang of traditional Chinese medicine and the scores of liver meridian syndrome factor,anxiety factor and depression factor all increased in the long-term emotional disturbance group significantly(P<0.05).The total scores of MoCA scale(after correction)and the level scores of visual space and executive function,attention and delayed recall decreased significantly(P<0.05),and the total scores of prospective memory questionnaire decreased significantly(P<0.05).The correct rates of ongoing tasks and prospective memory tasks in the event-based prospective memory dual task paradigm were decreased,and the reaction time was prolonged in the long-term emotional disorder group significantly(P<0.05).The amplitude of P200 of ongoing task and prospective memory task were increased in the long-term emotional disorder group(0.05

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.

In the era of precision medicine,integrating radionuclide-based molecular imaging with targeted internal radiotherapy,integrated theranostics of nuclear medicine emerged as a promising and rapidly advancing field to achieve both visualization and precise treatment of tumors.The advances of commonly used and emerging radiotheranostic agents in oncology were systematically reviewed in this article.

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.

In this study,the similarities and differences of plasma collection and quality control in China and abroad were analyzed by comparing the related regulations,standards,guidelines and literatures.Rational and constructive suggestions were proposed,aiming to optimize domestic plasma management and promote the improvement of plasma-related standards.There was little difference on facilities and safety control process of plasma between China and the developed countries(United States,EU and Japan),However,significant differences existed on plasma station setting,donor screening standards,collection interval,volume limits,plasma testing modes and tests,plasma quarantine standard and utilization of recovered plasma.The United States sets the industry benchmark and is worthy of reference for our country both in plasma collection and quality control.