Objective·To investigate the effects and molecular mechanisms of phosphatidylethanolamine(PE)on macrophage senescence and its senescence-associated secretory phenotype(SASP),as well as its pathophysiological role in liver injury.Methods·A macrophage senescence model was established using doxorubicin(DOX),followed by PE treatment.A mouse liver injury model was generated via intraperitoneal co-administration of PE and lipopolysaccharide(LPS)to investigate the effects of PE on liver injury.Senescence markers and SASP factors,including senescence-associated β-galactosidase(SA-β-gal),cell cycle inhibitor p21,tumor necrosis factor-α(TNF-α),and interleukin-6(IL-6),were evaluated using SA-β-gal staining,quantitative real-time PCR,and Western blotting.RNA sequencing(RNA-seq)was performed,followed by Gene Ontology(GO)cellular component enrichment analysis,Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis,Gene Set Variation Analysis(GSVA),and Gene Set Enrichment Analysis(GSEA),to explore the molecular mechanisms and signaling pathways by which PE promotes macrophage senescence.The expression of endoplasmic reticulum(ER)stress-related proteins,including inositol-requiring enzyme 1 α(IRE1α),spliced X-box binding protein 1(XBP1s),activating transcription factor 6(ATF6),ATF4,and C/EBP homologous protein(CHOP),was analyzed through in vivo and in vitro experiments.Results·PE significantly promoted the expression of senescence markers SA-β-gal,p21,p16 and SASP factors.RNA-seq analysis revealed that ER stress was involved in PE-induced promotion of SASP.Further experiments demonstrated that PE activated the ER stress signaling pathway,promoting macrophage senescence and the expression of SASP factors.In vivo experiments further confirmed that PE exacerbated LPS-induced liver injury in mice through ER stress.Conclusion·PE promotes macrophage senescence and the expression of SASP factors by activating ER stress signaling pathway,thereby aggravating LPS-induced liver injury.

Objective·To investigate the effects and molecular mechanisms of phosphatidylethanolamine(PE)on macrophage senescence and its senescence-associated secretory phenotype(SASP),as well as its pathophysiological role in liver injury.Methods·A macrophage senescence model was established using doxorubicin(DOX),followed by PE treatment.A mouse liver injury model was generated via intraperitoneal co-administration of PE and lipopolysaccharide(LPS)to investigate the effects of PE on liver injury.Senescence markers and SASP factors,including senescence-associated β-galactosidase(SA-β-gal),cell cycle inhibitor p21,tumor necrosis factor-α(TNF-α),and interleukin-6(IL-6),were evaluated using SA-β-gal staining,quantitative real-time PCR,and Western blotting.RNA sequencing(RNA-seq)was performed,followed by Gene Ontology(GO)cellular component enrichment analysis,Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis,Gene Set Variation Analysis(GSVA),and Gene Set Enrichment Analysis(GSEA),to explore the molecular mechanisms and signaling pathways by which PE promotes macrophage senescence.The expression of endoplasmic reticulum(ER)stress-related proteins,including inositol-requiring enzyme 1 α(IRE1α),spliced X-box binding protein 1(XBP1s),activating transcription factor 6(ATF6),ATF4,and C/EBP homologous protein(CHOP),was analyzed through in vivo and in vitro experiments.Results·PE significantly promoted the expression of senescence markers SA-β-gal,p21,p16 and SASP factors.RNA-seq analysis revealed that ER stress was involved in PE-induced promotion of SASP.Further experiments demonstrated that PE activated the ER stress signaling pathway,promoting macrophage senescence and the expression of SASP factors.In vivo experiments further confirmed that PE exacerbated LPS-induced liver injury in mice through ER stress.Conclusion·PE promotes macrophage senescence and the expression of SASP factors by activating ER stress signaling pathway,thereby aggravating LPS-induced liver injury.

ObjectiveTo investigate a cluster epidemic of coronavirus disease 2019 （COVID-19） infections in a school in Longchuan County， Yunnan Province， and further guide the prevention and control of COVID-19 in the border area. MethodsAccording to the Protocol on Prevention and Control of Novel Coronavirus Pneumonia （8th Edition）， an epidemiological investigation was performed on all COVID-19 cases to collect the information on demographics， onset， diagnosis and treatment， prognosis， and epidemiological history. Close contacts were also tracked to determine the transmission chains. ResultsIn this cluster epidemic， a total of 37 COVID-19 cases were identified， including 32 females and 5 males aged from 13 to 25 years， who were 35 students and 2 teachers. The student cases were found in four classes of two grades. Furthermore， gene sequencing showed that all cases had been infected with delta variants， belonging to the same transmission chain that was not related to the previous epidemics in Dehong Prefecture. In additionally， a total of 2 127 close contacts were found. After 21 days of centralized quarantine for medical observation， all close contacts tested negative for SARS-CoV-2. In the COVID-19 cases， only one case remained positive for SARS-CoV-2， while the other 36 cases were successfully treated and became negative. ConclusionThis school cluster is caused by the border villagers who contacted the water polluted with SARS-CoV-2. It warrants more strict management of students from border villages and their belongings to prevent similar epidemics in school settings.