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Effect of mutations on acetohydroxyacid synthase(AHAS)function in Cyperus difformis L.
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作者 Xiaotong Guo Xiangju Li +4 位作者 Zheng Li Licun Peng Jingchao Chen Haiyan Yu Hailan Cui 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期177-186,共10页
Cyperus difformis L.is a troublesome weed in paddy fields and has attracted attention due to its resistance to acetohydroxyacid synthase(AHAS)inhibitors.It was found that the amino acid mutation in AHAS was the primar... Cyperus difformis L.is a troublesome weed in paddy fields and has attracted attention due to its resistance to acetohydroxyacid synthase(AHAS)inhibitors.It was found that the amino acid mutation in AHAS was the primary cause for the resistance of Cyperus difformis.However,the effect of different mutations on AHAS function is not clear in Cyperus difformis.To confirm the effect of mutations on AHAS function,six biotypes were collected,including Pro197Arg,Pro197Ser,Pro197Leu,Asp376Glu,Trp574Leu and wild type,from Hunan,Anhui,Jiangxi and Jiangsu provinces,China and the function of AHAS was characterized.The AHAS in vitro inhibition assay results indicated that the mutations decreased the sensitivity of AHAS to pyrazosulfuron-ethyl,in which the I_(50)(the half maximal inhibitory concentration)of wild type AHAS was 0.04μmol L^(-1)and Asp376Glu,Pro197Leu,Pro197Arg,Pro197Ser and Trp574Leu mutations were 3.98,11.50,40.38,38.19 and 311.43μmol L^(-1),respectively.In the determination of enzyme kinetics parameters,the Km and the maximum reaction velocity(Vmax)of the wild type were 5.18 mmol L^(-1)and 0.12 nmol mg^(-1)min^(-1),respectively,and the Km values of AHAS with Asp376Glu,Trp574Leu,Pro197Leu and Pro197Ser mutations were 0.38-0.93 times of the wild type.The Km value of the Pro197Arg mutation was 1.14times of the wild type,and the Vmax values of the five mutations were 1.17-3.33-fold compared to the wild type.It was found that the mutations increased the affinity of AHAS to the substrate,except for the Pro197Arg mutation.At a concentration of 0.0032-100 mmol L^(-1)branched-chain amino acids(BCAAs),the sensitivity of the other four mutant AHAS biotypes to feedback inhibition decreased,except for the Pro197Arg mutation.This study elucidated the effect of different mutations on AHAS function in Cyperus difformis and provided ideas for further study of resistance development. 展开更多
关键词 acetohydroxyacid synthase(ahas) MUTATION enzyme function Cyperus difformis
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Phytoene synthases 1 modulates tomato fruit quality through influencing the metabolic flux between carotenoid and flavonoid pathways
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作者 Xue Cao Ran Du +13 位作者 Yuanchao Xu Yaoyao Wu Keyi Ye Jing Ma Yaqing Lyu Tianshu Sun Xijian Zhu Zhihong Liu Jian Yin Guangtao Zhu Zejun Huang Hongjun Lyu Sanwen Huang Jinzhe Zhang 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第6期1383-1397,共15页
The deterioration in fruit quality of commercial tomatoes is a major concern of modern tomato breeding.However,the metabolism and genetics of fruit quality are poorly understood.Here,we performed transgenic and molecu... The deterioration in fruit quality of commercial tomatoes is a major concern of modern tomato breeding.However,the metabolism and genetics of fruit quality are poorly understood.Here,we performed transgenic and molecular biology experiments to reveal that tomato phytoene synthase 1(SlPSY1)is responsible for the accumulation of an important flavor chemical,6-methyl-5-hepten-2-one(MHO).To dissect the function of SlPSY1 in regulating fruit quality,we generated and analyzed a dataset encompassing over 2000 compounds detected by GC-MS and LC-MS/MS along with transcriptomic data.The combined results illustrated that SlPSY1 deficiency imparts novel flavor to yellow tomatoes with 236 volatiles significantly changed and improves fruit firmness,possibly due to accumulation of seven cutins.Further analysis indicated SlPSY1 is essential for carotenoid-derived metabolite biosynthesis by catalyzing prephytoene-PP(PPPP)to 15-cis-phytoene.Notably,we showed that SlPSY1 can influence the metabolic flux between carotenoid and flavonoid pathways,and this metabolic flux was confirmed by silencing SlCHS1.Our study provided insights into the multiple effects of SlPSY1 on tomato fruit metabolome and highlights the potential to produce high-quality fruit by rational design of SlPSY1 expression. 展开更多
关键词 TOMATO FLAVOR METABOLOME Phytoene synthase 1 CAROTENOID Flavonoid
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Enhancing the radiosensitivity of colorectal cancer cells by reducing spermine synthase through promoting autophagy and DNA damage
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作者 Yu-Bin Guo Yue-Ming Wu Zhi-Zhao Lin 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第12期4716-4727,共12页
BACKGROUND Colorectal cancer(CRC),the third most common cancer worldwide,has increasingly detrimental effects on human health.Radiotherapy resistance diminishes treatment efficacy.Studies suggest that spermine synthas... BACKGROUND Colorectal cancer(CRC),the third most common cancer worldwide,has increasingly detrimental effects on human health.Radiotherapy resistance diminishes treatment efficacy.Studies suggest that spermine synthase(SMS)may serve as a potential target to enhance the radiosensitivity.AIM To investigate the association between SMS and radiosensitivity in CRC cells,along with a detailed elucidation of the underlying mechanisms.METHODS Western blot was adopted to assess SMS expression in normal colonic epithelial cells and CRC cell lines.HCT116 cells were transfected with control/SMS-specific shRNA or control/pcDNA3.1-SMS plasmids.Assessments included cell viability,colony formation,and apoptosis via MTT assays,colony formation assays,and flow cytometry.Radiosensitivity was studied in SMS-specific shRNA-transfected HCT116 cells post-4 Gy radiation,evaluating cell viability,colony formation,apoptosis,DNA damage(comet assays),autophagy(immunofluorescence),and mammalian target of rapamycin(mTOR)pathway protein expression(western blot).RESULTS Significant up-regulation of SMS expression levels was observed in the CRC cell lines.Upon down-regulation of SMS expression,cellular viability and colonyforming ability were markedly suppressed,concomitant with a notable increase in apoptotic indices.Furthermore,attenuation of SMS expression significantly augmented the sensitivity of HCT116 cells to radiation therapy,evidenced by a pronounced elevation in levels of cellular DNA damage and autophagy.Impor tantly,down-regulation of SMS corresponded with a marked reduction in the expression levels of proteins associated with the mTOR signaling pathway.CONCLUSION Knocking down SMS attenuates the mTOR signaling pathway,thereby promoting cellular autophagy and DNA damage to enhance the radiosensitivity of CRC cells. 展开更多
关键词 Spermine synthase Colorectal cancer RADIOSENSITIVITY AUTOPHAGY DNA damage
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The gene encoding flavonol synthase contributes to lesion mimic in wheat
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作者 Tingting Dong Hongchun Xiong +8 位作者 Huijun Guo Yongdun Xie Linshu Zhao Jiayu Gu Huiyuan Li Shirong Zhao Yuping Ding Xiyun Song Luxiang Liu 《The Crop Journal》 SCIE CSCD 2024年第3期814-825,共12页
Lesion mimic often exhibits leaf disease-like symptoms even in the absence of pathogen infection,and is characterized by a hypersensitive-response(HR)that closely linked to plant disease resistance.Despite this,only a... Lesion mimic often exhibits leaf disease-like symptoms even in the absence of pathogen infection,and is characterized by a hypersensitive-response(HR)that closely linked to plant disease resistance.Despite this,only a few lesion mimic genes have been identified in wheat.In this investigation,a lesion mimic wheat mutant named je0297 was discovered,showing no alteration in yield components when compared to the wild type(WT).Segregation ratio analysis of the F_(2)individuals resulting from the cross between the WT and the mutant revealed that the lesion mimic was governed by a single recessive gene in je0297.Using Bulked segregant analysis(BSA)and exome capture sequencing,we mapped the lesion mimic gene designated as lm6 to chromosome 6BL.Further gene fine mapping using 3315 F_(2)individuals delimited the lm6 within a 1.18 Mb region.Within this region,we identified 16 high-confidence genes,with only two displaying mutations in je0297.Notably,one of the two genes,responsible for encoding flavonol synthase,exhibited altered expression levels.Subsequent phenotype analysis of TILLING mutants confirmed that the gene encoding flavonol synthase was indeed the causal gene for lm6.Transcriptome sequencing analysis revealed that the DEGs between the WT and mutant were significantly enriched in KEGG pathways related to flavonoid biosynthesis,including flavone and flavonol biosynthesis,isoflavonoid biosynthesis,and flavonoid biosynthesis pathways.Furthermore,more than 30 pathogen infection-related(PR)genes exhibited upregulation in the mutant.Corresponding to this expression pattern,the flavonoid content in je0297 showed a significant decrease in the 4^(th)leaf,accompanied by a notable accumulation of reactive oxygen,which likely contributed to the development of lesion mimic in the mutant.This investigation enhances our comprehension of cell death signaling pathways and provides a valuable gene resource for the breeding of disease-resistant wheat. 展开更多
关键词 Lesion mimic mutant WHEAT Gene mapping Flavonol synthase gene Flavonoid
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Genome-wide identification and function analysis of the sucrose phosphate synthase MdSPS gene family in apple 被引量:2
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作者 ZHANG Li-hua ZHU Ling-cheng +7 位作者 XU Yu LÜLong LI Xing-guo LI Wen-hui LIU Wan-da MA Feng-wang LI Ming-jun HAN De-guo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第7期2080-2093,共14页
Sucrose phosphate synthase(SPS)is a rate-limiting enzyme that works in conjunction with sucrose-6-phosphate phosphatase(SPP)for sucrose synthesis,and it plays an essential role in energy provisioning during growth and... Sucrose phosphate synthase(SPS)is a rate-limiting enzyme that works in conjunction with sucrose-6-phosphate phosphatase(SPP)for sucrose synthesis,and it plays an essential role in energy provisioning during growth and development in plants as well as improving fruit quality.However,studies on the systematic analysis and evolutionary pattern of the SPS gene family in apple are still lacking.In the present study,a total of seven MdSPS and four MdSPP genes were identified from the Malus domestica genome GDDH13 v1.1.The gene structures and their promoter cis-elements,protein conserved motifs,subcellular localizations,physiological functions and biochemical properties were analyzed.A chromosomal location and gene-duplication analysis demonstrated that whole-genome duplication(WGD)and segmental duplication played vital roles in MdSPS gene family expansion.The Ka/Ks ratio of pairwise MdSPS genes indicated that the members of this family have undergone strong purifying selection during domestication.Furthermore,three SPS gene subfamilies were classified based on phylogenetic relationships,and old gene duplications and significantly divergent evolutionary rates were observed among the SPS gene subfamilies.In addition,a major gene related to sucrose accumulation(MdSPSA2.3)was identified according to the highly consistent trends in the changes of its expression in four apple varieties(‘Golden Delicious’,‘Fuji’,‘Qinguan’and‘Honeycrisp’)and the correlation between gene expression and soluble sugar content during fruit development.Furthermore,the virus-induced silencing of MdSPSA2.3 confirmed its function in sucrose accumulation in apple fruit.The present study lays a theoretical foundation for better clarifying the biological functions of the MdSPS genes during apple fruit development. 展开更多
关键词 APPLE sucrose phosphate synthase evolutionary pattern expression profile sugar accumulation
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Mutations in Plasmodium knowlesi Kelch protein 13 and the dihydropteroate synthase gene in clinical samples 被引量:1
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作者 Ahmed Saif 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2023年第2期72-79,I0004,I0005,I0006,I0007,共12页
Objective:To determine the genetic diversity,natural selection and mutations in Plasmodium(P.)knowlesi drug resistant molecular markers Kelch 13 and dhps gene in clinical samples of Malaysia.Methods:P.knowlesi full-le... Objective:To determine the genetic diversity,natural selection and mutations in Plasmodium(P.)knowlesi drug resistant molecular markers Kelch 13 and dhps gene in clinical samples of Malaysia.Methods:P.knowlesi full-length gene sequences Kelch 13 gene(PkK13)from 40 samples and dhps gene from 30 samples originating from Malaysian Borneo were retrieved from public databases.Genetic diversity,natural selection,and phylogenetic analysis of gene sequences were analysed using DNAsp v5.10 and MEGA v5.2.Results:Seventy-two single nucleotide polymorphic sites(SNPs)across the full-length PkK13 gene(63 synonymous substitutions and 9 non-synonymous substitutions)with nucleotide diversity ofπ~0.005 was observed.Analysis of the full-length Pkdhps gene revealed 73 SNPs andπ~0.006(44 synonymous substitutions and 29 non-synonymous substitutions).A high number of haplotypes(PkK13;H=37 and Pkdhps;H=29)with haplotype diversity of Hd~0.99 were found in both genes,indicating population expansion.Nine mutant alleles were identified in PkK13 amino acid alignment of which,7(Asp3Glu,Lys50Gln,Lys53Glu,Ser123Thr,Ser127Pro,Ser149Thr and Ala169Thr)were within the Plasmodium specific domain,2(Val372Ile and Lys424Asn)were in the BTB/POZ domain and no mutation was observed within the kelch propeller domain.The 29 non-synonymous mutations in the Pkdhps gene were novel and only presented in exon 1 and 2.Conclusions:Monitoring the mutations from clinical samples collected from all states of Malaysia along with clinical efficacy studies will be necessary to determine the drug resistance in P.knowlesi. 展开更多
关键词 Plasmodium knowlesi Kelch 13 dhps Dihydropteroate synthase Drug resistance MUTATION
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Metformin promotes angiogenesis and functional recovery in aged mice after spinal cord injury by adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway 被引量:3
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作者 Jin-Yun Zhao Xiao-Long Sheng +7 位作者 Cheng-Jun Li Tian Qin Run-Dong He Guo-Yu Dai Yong Cao Hong-Bin Lu Chun-Yue Duan Jian-Zhong Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第7期1553-1562,共10页
Treatment with metformin can lead to the recovery of pleiotropic biological activities after spinal cord injury.However,its effect on spinal cord injury in aged mice remains unclear.Considering the essential role of a... Treatment with metformin can lead to the recovery of pleiotropic biological activities after spinal cord injury.However,its effect on spinal cord injury in aged mice remains unclear.Considering the essential role of angiogenesis during the regeneration process,we hypothesized that metformin activates the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway in endothelial cells,thereby promoting microvascular regeneration in aged mice after spinal cord injury.In this study,we established young and aged mouse models of contusive spinal cord injury using a modified Allen method.We found that aging hindered the recovery of neurological function and the formation of blood vessels in the spinal cord.Treatment with metformin promoted spinal cord microvascular endothelial cell migration and blood vessel formation in vitro.Furthermore,intraperitoneal injection of metformin in an in vivo model promoted endothelial cell proliferation and increased the density of new blood vessels in the spinal cord,thereby improving neurological function.The role of metformin was reversed by compound C,an adenosine monophosphate-activated protein kinase inhibitor,both in vivo and in vitro,suggesting that the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway likely regulates metformin-mediated angiogenesis after spinal cord injury.These findings suggest that metformin promotes vascular regeneration in the injured spinal cord by activating the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway,thereby improving the neurological function of aged mice after spinal cord injury. 展开更多
关键词 adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway ANGIOGENESIS aged mice compound C METFORMIN spinal cord injury
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Glycogen Synthase Kinase-3β,NLRP3 Inflammasome,and Alzheimer's Disease 被引量:1
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作者 Yue-ran JIA Zi-qing GUO +1 位作者 Qian GUO Xiao-chuan WANG 《Current Medical Science》 SCIE CAS 2023年第5期847-854,共8页
Alzheimer’s disease (AD) is the most prevalent cause of dementia worldwide. Because of the progressive neurodegeneration, individual cognitive and behavioral functions are impaired, affecting the quality of life of m... Alzheimer’s disease (AD) is the most prevalent cause of dementia worldwide. Because of the progressive neurodegeneration, individual cognitive and behavioral functions are impaired, affecting the quality of life of millions of people. Although the exact pathogenesis of AD has not been fully elucidated, amyloid plaques, neurofibrillary tangles (NFTs), and sustaining neuroinflammation dominate its characteristics. As one of the major tau kinases leading to hyperphosphorylation and aggregation of tau, glycogen synthase kinase-3β (GSK-3β) has been drawing great attention in various AD studies. Another research focus of AD in recent years is the inflammasome, a multiprotein complex acting as a regulator in immunological reactions to exogenous and endogenous danger signals, of which the Nod-like receptor (NLR) family, pyrin domain-containing 3 (NLRP3) inflammasome has been studied mostly in AD and proven to play a significant role in AD development by its activation and downstream effects such as caspase-1 maturation and interleukin (IL)-1β release. Studies have shown that the NLRP3 inflammasome is activated in a GSK-3β-dependent way and that inhibition of the NLRP3 inflammasome downregulates GSK-3β, suggesting that these two important proteins are closely related. This article reviews the respective roles of GSK-3β and the NLRP3 inflammasome in AD as well as their relationship and interaction. 展开更多
关键词 glycogen synthase kinase-3β NLRP3 inflammasome Alzheimer's disease
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Neuronal nitric oxide synthase/reactive oxygen species pathway is involved in apoptosis and pyroptosis in epilepsy 被引量:2
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作者 Xiao-Xue Xu Rui-Xue Shi +11 位作者 Yu Fu Jia-Lu Wang Xin Tong Shi-Qi Zhang Na Wang Mei-Xuan Li Yu Tong Wei Wang Miao He Bing-Yang Liu Gui-Lan Chen Feng Guo 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第6期1277-1285,共9页
Dysfunction of neuronal nitric oxide synthase contributes to neurotoxicity,which triggers cell death in various neuropathological diseases,including epilepsy.Studies have shown that inhibition of neuronal nitric oxide... Dysfunction of neuronal nitric oxide synthase contributes to neurotoxicity,which triggers cell death in various neuropathological diseases,including epilepsy.Studies have shown that inhibition of neuronal nitric oxide synthase activity increases the epilepsy threshold,that is,has an anticonvulsant effect.However,the exact role and potential mechanism of neuronal nitric oxide synthase in seizures are still unclear.In this study,we performed RNA sequencing,functional enrichment analysis,and weighted gene coexpression network analysis of the hippocampus of tremor rats,a rat model of genetic epilepsy.We found damaged hippocampal mitochondria and abnormal succinate dehydrogenase level and Na+-K+-ATPase activity.In addition,we used a pilocarpine-induced N2a cell model to mimic epileptic injury.After application of neuronal nitric oxide synthase inhibitor 7-nitroindazole,changes in malondialdehyde,lactate dehydrogenase and superoxide dismutase,which are associated with oxidative stress,were reversed,and the increase in reactive oxygen species level was reversed by 7-nitroindazole or reactive oxygen species inhibitor N-acetylcysteine.Application of 7-nitroindazole or N-acetylcysteine downregulated the expression of caspase-3 and cytochrome c and reversed the apoptosis of epileptic cells.Furthermore,7-nitroindazole or N-acetylcysteine downregulated the abnormally high expression of NLRP3,gasdermin-D,interleukin-1βand interleukin-18.This indicated that 7-nitroindazole and N-acetylcysteine each reversed epileptic cell death.Taken together,our findings suggest that the neuronal nitric oxide synthase/reactive oxygen species pathway is involved in pyroptosis of epileptic cells,and inhibiting neuronal nitric oxide synthase activity or its induced oxidative stress may play a neuroprotective role in epilepsy. 展开更多
关键词 APOPTOSIS bioinformatics analysis cell death EPILEPSY nitric oxide synthase oxidative stress PYROPTOSIS RNA sequencing Tremor rat weighted gene co-expression network analysis
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Prostaglandin F_(2α)synthase promotes oxaliplatin resistance in colorectal cancer through prostaglandin F_(2α)-dependent and F_(2α)-independent mechanism 被引量:1
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作者 Yi-Jun Wang Xiao-Li Xie +10 位作者 Hong-Qun Liu Hui Tian Xiao-Yu Jiang Jiu-Na Zhang Sheng-Xiong Chen Ting Liu Shu-Ling Wang Xue Zhou Xiao-Xu Jin Shi-Mao Liu Hui-Qing Jiang 《World Journal of Gastroenterology》 SCIE CAS 2023年第39期5452-5470,共19页
BACKGROUND Oxaliplatin(Oxa)is the first-line chemotherapy drug for colorectal cancer(CRC),and Oxa resistance is crucial for treatment failure.Prostaglandin F_(2α)synthase(PGF 2α)(PGFS),an enzyme that catalyzes the p... BACKGROUND Oxaliplatin(Oxa)is the first-line chemotherapy drug for colorectal cancer(CRC),and Oxa resistance is crucial for treatment failure.Prostaglandin F_(2α)synthase(PGF 2α)(PGFS),an enzyme that catalyzes the production of PGF_(2α),is involved in the proliferation and growth of a variety of tumors.However,the role of PGFS in Oxa resistance in CRC remains unclear.AIM To explore the role and related mechanisms of PGFS in mediating Oxa resistance in CRC.METHODS The PGFS expression level was examined in 37 pairs of CRC tissues and paracancerous tissues at both the mRNA and protein levels.Overexpression or knockdown of PGFS was performed in CRC cell lines with acquired Oxa resistance(HCT116-OxR and HCT8-OxR)and their parental cell lines(HCT116 and HCT8)to assess its influence on cell proliferation,chemoresistance,apoptosis,and DNA damage.For determination of the underlying mechanisms,CRC cells were examined for platinum-DNA adducts and reactive oxygen species(ROS)levels in the presence of a PGFS inhibitor or its products.RESULTS Both the protein and mRNA levels of PGFS were increased in the 37 examined CRC tissues compared to the adjacent normal tissues.Oxa induced PGFS expression in the parental HCT116 and HCT8 cells in a dosedependent manner.Furthermore,overexpression of PGFS in parental CRC cells significantly attenuated Oxainduced proliferative suppression,apoptosis,and DNA damage.In contrast,knockdown of PGFS in Oxa-resistant HCT116 and HCT8 cells(HCT116-OxR and HCT8-OxR)accentuated the effect of Oxa treatment in vitro and in vivo.The addition of the PGFS inhibitor indomethacin enhanced the cytotoxicity caused by Oxa.Treatment with the PGFS-catalyzed product PGF_(2α)reversed the effect of PGFS knockdown on Oxa sensitivity.Interestingly,PGFS inhibited the formation of platinum-DNA adducts in a PGF_(2α)-independent manner.PGF_(2α)exerts its protective effect against DNA damage by reducing ROS levels.CONCLUSION PGFS promotes resistance to Oxa in CRC via both PGF_(2α)-dependent and PGF_(2α)-independent mechanisms. 展开更多
关键词 Prostaglandin F_(2α)synthase Colorectal cancer OXALIPLATIN Drug resistance DNA damage
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Identifi cation of sesquiterpene synthase genes in the genome of Aquilaria sinensis and characterization of anα-humulene synthase
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作者 Jiadong Ran Yuan Li +5 位作者 Xin Wen Xin Geng Xupeng Si Liping Zhang Yimian Ma Zheng Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第4期1117-1131,共15页
Sesquiterpenes are the major pharmacodynamic components of agarwood,a precious traditional Chinese medicine obtained from the resinous portions of Aquilaria sinensis trees that form in response to environmental stress... Sesquiterpenes are the major pharmacodynamic components of agarwood,a precious traditional Chinese medicine obtained from the resinous portions of Aquilaria sinensis trees that form in response to environmental stressors.To characterize the sesquiterpene synthases responsible for sesquiterpene production in A.sinensis,a bioinformatics analysis of the genome of A.sinensis identifi ed six new terpene synthase genes,and 16 sesquiterpene synthase genes were identifi ed as type TPS-a in a phylogenetic analysis.The expression patterns for eight of the sesquiterpene synthase genes after treatment with various hormones or hydrogen peroxide were analyzed by real-time quantitative PCR.The results suggest that 100μM methyl jasmonate,ethephon,(±)-abscisic acid or hydrogen peroxide could be eff ective short-term eff ectors to increase the expression of sesquiterpene synthase genes,while 1 mM methyl salicylate may have long-term eff ects on increasing the expression of specifi c sesquiterpene synthase genes(e.g.,As-SesTPS,AsVS,AsTPS12 and AsTPS29).The expression changes in these genes under various conditions refl ected their specifi c roles during abiotic or biotic stresses.Heterologous expression of a novel A.sinensis sesquiterpene synthase gene,AsTPS2,in Escherichia coli produced a major humulene product,so AsTPS2 is renamed AsHS1.AsHS1 is diff erent from ASS1,AsSesTPS,and AsVS,for mainly producingα-humulene.Based on the predicted space conformation of the AsHS1 model,the small ligand molecule may bind to the free amino acid by hydrogen bonding for the catalytic function of the enzyme,while the substrate farnesyl diphosphate(FPP)probably binds to the free amino acid on one side of the RxR motif.Arg450,Asp453,Asp454,Thr457,and Glu461 from the NSE/DTE motif and D307 and D311 from the DDxxD motif were found to form a polar interaction with two Mg^(2+)clusters by docking.The Mg^(2+)-bound DDxxD and NSE/DTE motifs and the free RXR motif are jointly directed into the catalytic pocket of AsHS1.Comparison of the tertiary structural models of AsHS1 with ASS1 showed that they diff ered in structures in several positions,such as surrounding the secondary catalytic pocket,which may lead to diff erences in catalytic products.Based on the results,biosynthetic pathways for specifi c sesquiterpenes such asα-humulene in A.sinensis are proposed.This study provides novel insights into the functions of the sesquiterpene synthases of A.sinensis and enriches knowledge on agarwood formation. 展开更多
关键词 AGARWOOD Aquilaria sinensis Sesquiterpene synthase Humulene
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A nonsynonymous mutation in an acetolactate synthase gene (Gh_D10G1253) is required for tolerance to imidazolinone herbicides in cotton
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作者 CHEN Tianzi LING Xitie +1 位作者 YU Yue ZHANG Baolong 《Journal of Cotton Research》 CAS 2023年第1期25-36,共12页
Background Herbicide tolerance in crops enables them to survive when lethal doses of herbicides are applied to surrounding weeds.Herbicide-tolerant crops can be developed through transgenic approaches or traditional m... Background Herbicide tolerance in crops enables them to survive when lethal doses of herbicides are applied to surrounding weeds.Herbicide-tolerant crops can be developed through transgenic approaches or traditional mutagenesis approaches.At present,no transgenic herbicide tolerant cotton have been commercialized in China due to the genetically-modified organism(GMO)regulation law.We aim to develop a non-transgenic herbicide-tolerant cotton through ethyl methanesulfonate(EMS)mutagenesis,offering an alternative choice for weed management.Results Seeds of an elite cotton cultivar Lumianyan 37(Lu37)were treated with EMS,and a mutant Lu37-1 showed strong tolerance to imidazolinone(IMI)herbicides was identified.A novel nonsynonymous substitution mutation Ser642Asn at acetolactate synthase(ALS)(Gh_D10G1253)in Lu37-1 mutant line was found to be the potential cause to the IMI herbicides tolerance in cotton.The Ser642Asn mutation in ALS did not present among the genomes of natural Gossypium species.Cleaved amplified polymorphic sequence(CAPS)markers were developed to identify the ALS mutant allele.The Arabidopsis overexpressing the mutanted ALS also showed high tolerance to IMI herbicides.Conclusion The nonsynonymous substitution mutation Ser642Asn of the ALS gene Gh_D10G1253 is a novel identi-fied mutation in cotton.This substitution mutation has also been identified in the orthologous ALS genes in other crops.This mutant ALS allele can be used to develop IMI herbicide-tolerant crops via a non-transgenic or transgenic approach. 展开更多
关键词 Acetolactate synthase COTTON EMS mutagenesis Herbicide tolerance IMIDAZOLINONE
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Identification and Pathogen Stimulation Patterns of Neuronal Nitric Oxide Synthase(nNOS)in Black Rockfish(Sebastes schlegelii)
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作者 YAN Xu WANG Ningning +5 位作者 CAO Min LI Chao YANG Ning XUE Ting FU Qiang SONG Lin 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第3期842-850,共9页
Neuronal nitric oxide synthase(nNOS)was the producer of nitric oxide(NO)which played important gas messenger molecules in biological process.It also can take effect as immune regulation molecule in organism.Black rock... Neuronal nitric oxide synthase(nNOS)was the producer of nitric oxide(NO)which played important gas messenger molecules in biological process.It also can take effect as immune regulation molecule in organism.Black rockfish(Sebastes schlegelii)is an important economic fish which were widely farmed in East Asia countries.Meanwhile,the pathogenic bacteria such as the Edwardsiella tarda and Vibrio anguillarum in seawater always brought serious obstacles to their healthy growth.In order to explore the expression pattern of n NOS gene under the pathogen stimulation and predict its immune function,the n NOS gene in black rockfish named Ssn NOS was identified.It was 3780 bp in length,located on chromosome 6,and contained 27 coding domain sequence(CDs).According to the phylogenetic analysis,the Ssn NOS showed closest relative to the counterpart gene of swamp eel(Monopterus albus).Meanwhile,analysis of Ssn NOS expression in various healthy tissues showed that Ssn NOS expression level was highest in healthy brain tissues,followed by intestinal tissues.In addition,Ssn NOS showed significant expression changes in response to stimulation by two pathogens.Particular in gill,the expression of Ssn NOS after pathogenic stimulation increased significantly.The Elisa analysis showed the Ssn NOS content in gills was much higher than that in other tissues at all time points.Moreover,the expression patterns of Ssn NOS in brain,intestine and kidney after stimulation by pathogens showed a distinct expression pattern which first down-regulated and then up-regulated.Therefore,the Ssn NOS may be an important signaling molecule for fish to respond rapidly in immune stimulation. 展开更多
关键词 neuronal nitric oxide synthase black rockfish immune function Edwardsiella tarda Vibrio anguillarum
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ZmMS39 encodes a callose synthase essential for male fertility in maize(Zea mays L.)
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作者 Qunkai Niu Ziwen Shi +11 位作者 Peng Zhang Shuai Su Bin Jiang Xiaowei Liu Zhuofan Zhao Suzhi Zhang Qiang Huang Chuan Li Tao Yu Hongyang Yi Tingzhao Rong Moju Cao 《The Crop Journal》 SCIE CSCD 2023年第2期394-404,共11页
Callose contributes to many biological processes of higher plants including pollen development,cell plate and vascular tissue formation,as well as regulating the transport function of plasmodesmata.The functions of ca... Callose contributes to many biological processes of higher plants including pollen development,cell plate and vascular tissue formation,as well as regulating the transport function of plasmodesmata.The functions of callose synthase genes in maize have been little studied.We describe a maize male-sterile mutant 39(ms39)characterized by reduced plant height.In this study,we confirmed using CRISPR/Cas9 technology that a mutation in Zm00001d043909(ZmCals12),encoding a callose synthase,is responsible for the male sterility of the ms39 mutant.Compared with male-fertile plants,callose deposition around the dyads and tetrads in ms39 anthers was significantly reduced.Increased cell autophagy observed in ms39 anthers may have been due to the premature programmed cell death of tapetal cells,leading to collapse of the anther wall structure.Disordered glucose metabolism in ms39 may have intensified autophagy in anthers.Evaluation of the ms39 gene on maize heterosis by paired-crossed experiment with 11 maize inbred lines indicated that ms39 can be used for maize hybrid seed production. 展开更多
关键词 MAIZE Genic male sterility Callose synthase Tapetal PCD Anther and pollen development AUTOPHAGY
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Correlation between the expressions of metastasis-associated factor-1 in colon cancer and vacuolar ATP synthase
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作者 Miao He Zuo-Feng Cao +4 位作者 Li Huang Wen-Juan Zhong Xue-Ming Xu Xiao-Li Zeng Jing Wang 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第11期2463-2469,共7页
BACKGROUND Clinical prognosis often worsens due to high recurrence rates following radical surgery for colon cancer.The examination of high-risk recurrence factors post-surgery provides critical insights for disease e... BACKGROUND Clinical prognosis often worsens due to high recurrence rates following radical surgery for colon cancer.The examination of high-risk recurrence factors post-surgery provides critical insights for disease evaluation and treatment planning.AIM To explore the relationship between metastasis-associated factor-1 in colon cancer(MACC1)and vacuolar ATP synthase(V-ATPase)expression in colon cancer tissues,and recurrence rate in patients undergoing radical colon cancer surgery.METHODS We selected 104 patients treated with radical colon cancer surgery at our hospital from January 2018 to June 2021.Immunohistochemical staining was utilized to assess the expression levels of MACC1 and V-ATPase in these patients.RESULTS The rates of MACC1 and V-ATPase positivity were 64.42%and 67.31%,respe-ctively,in colon cancer tissues,which were significantly higher than in paracan-cerous tissues(P<0.05).Among patients with TNM stage III,medium to low differentiation,and lymph node metastasis,the positive rates of MACC1 and V-ATPase were significantly elevated in comparison to patients with TNM stage I-II,high differentiation,and no lymph node metastasis(P<0.05).The rate of MACC1 positivity was 76.67%in patients with tumor diameters>5 cm,notably higher than in patients with tumor diameters≤5 cm(P<0.05).We observed a positive correlation between MACC1 and V-ATPase expression(rs=0.797,P<0.05).The positive rates of MACC1 and V-ATPase were significantly higher in patients with recurrence compared to those without(P<0.05).Logistic regression analysis revealed TNM stage,lymph node metastasis,MACC1 expression,and V-ATPase expression as risk factors for postoperative colon cancer recurrence(OR=6.322,3.435,2.683,and 2.421;P<0.05).CONCLUSION The upregulated expression of MACC1 and V-ATPase in colon cancer patients appears to correlate with clinicopathological features and post-radical surgery recurrence. 展开更多
关键词 Metastasis-associated factor-1 in colon cancer Vacuolar ATP synthase Colon cancer Radical surgery Recurrence
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内皮型一氧化氮合酶在运动预适应改善心肌缺血-再灌注损伤中的作用 被引量:1
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作者 娄国 张艳 付常喜 《中国组织工程研究》 CAS 北大核心 2024年第8期1283-1288,共6页
背景:运动是防治各种心血管疾病并保护心脏免受缺血-再灌注损伤的有效策略,其作用机制有待深入研究。目的:观察有氧运动预适应对心肌缺血-再灌注损伤的影响,并探讨内皮型一氧化氮合酶(endothelial nitric oxide synthase,eNOS)激活(包... 背景:运动是防治各种心血管疾病并保护心脏免受缺血-再灌注损伤的有效策略,其作用机制有待深入研究。目的:观察有氧运动预适应对心肌缺血-再灌注损伤的影响,并探讨内皮型一氧化氮合酶(endothelial nitric oxide synthase,eNOS)激活(包括偶联和磷酸化)在其间的作用。方法:取80只成年Wistar大鼠,采用随机数字表法分为安静组(n=40)和运动组(n=40),运动组进行8周有氧运动,安静组在鼠笼内安静饲养。8周后进行3项实验:①实验1:末次训练后,检测大鼠心功能、心脏NO代谢物含量及心脏eNOS、磷酸化eNOS-S1177、eNOS二聚体、eNOS单体的蛋白表达量;②实验2:将大鼠分为安静对照组、运动对照组、安静+eNOS抑制剂组、运动+eNOS抑制剂组,均进行体外心肌缺血-再灌注损伤实验,安静+eNOS抑制剂组、运动+eNOS抑制剂组再灌注前10 min持续灌注eNOS抑制剂,再灌注3 h后检测心功能与心肌梗死面积;③实验3:将大鼠分为安静对照组、运动对照组、安静+eNOS偶联剂组和运动+eNOS偶联剂组,均进行体外心肌缺血-再灌注损伤实验,安静+eNOS偶联剂组和运动+eNOS偶联剂组再灌注前10 min持续灌注eNOS偶联剂,再灌注3 h后检测心肌梗死面积、心脏NO代谢物含量及心脏eNOS、磷酸化eNOS-S1177、eNOS二聚体、eNOS单体和3-硝基酪氨酸的蛋白表达量(其中,磷酸化eNOS-S1177/eNOS比值反映eNOS磷酸化/去磷酸化水平,eNOS二聚体/单体比值反映eNOS偶联/解偶联水平)。结果与结论:①实验1:与安静组比较,运动组大鼠心输出量、左心室射血分数升高(P<0.05),亚硝酸盐和S-亚硝基硫醇含量升高(P<0.05),磷酸化eNOS-S1177、eNOS蛋白表达和磷酸化eNOS-S1177/eNOS比值上调(P<0.05),eNOS二聚体蛋白表达和eNOS二聚体/单体比值升高(P<0.05);②实验2:与安静对照组比较,运动对照组左心室发展压升高(P<0.05),心肌梗死面积下降(P<0.05);与运动对照组比较,运动+eNOS抑制剂组左心室发展压降低(P<0.05),心肌梗死面积增加(P<0.05);③实验3:与安静对照组比较,运动对照组左心室发展压升高(P<0.05),心肌梗死面积下降(P<0.05),磷酸化eNOS-S1177/eNOS比值下降(P<0.05),eNOS二聚体/单体比值下降(P<0.05),S-亚硝基硫醇含量增加(P<0.05),3-硝基酪氨酸蛋白表达量下调(P<0.05);与运动对照组比较,运动+eNOS偶联剂组左心室发展压降低(P<0.05),心肌梗死面积增加(P<0.05),磷酸化eNOS-S1177/eNOS比值升高(P<0.05),eNOS二聚体/单体比值升高(P<0.05),3-硝基酪氨酸蛋白表达升高(P<0.05);④结果表明:有氧运动预适应可诱导心脏保护效应,其机制与心脏缺血-再灌注期间eNOS解偶联以及去磷酸化进而抑制NO过度产生并降低硝基-氧化应激有关。 展开更多
关键词 运动预适应 内皮型一氧化氮合酶 磷酸化/去磷酸化 偶联/解偶联 缺血-再灌注损伤 硝基-氧化应激
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聚酮化合物非天然延伸单元的生物合成与结构改造应用 被引量:1
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作者 张俊 金诗雪 +1 位作者 云倩 瞿旭东 《合成生物学》 CSCD 北大核心 2024年第3期561-570,共10页
聚酮天然产物包括10000多种具有广泛生物活性的分子,是获批临床药物中最著名的类别之一。已知活性先导化合物通常需要经过结构修饰改良其吸收、分布、代谢和排泄等特性,从而促进成药开发,但针对聚酮化合物的结构修饰极具挑战,需要应对... 聚酮天然产物包括10000多种具有广泛生物活性的分子,是获批临床药物中最著名的类别之一。已知活性先导化合物通常需要经过结构修饰改良其吸收、分布、代谢和排泄等特性,从而促进成药开发,但针对聚酮化合物的结构修饰极具挑战,需要应对聚酮骨架中大量的立体中心以及多个惰性碳原子,导致化学合成手段难以对聚酮骨架进行精准和高效的衍生化,因此,通过合成生物学方法实现其结构优化就成为了研究者们关注的热点。自然界中,绝大多数聚酮化合物主要由简单的乙酸盐和丙酸盐结构单元通过聚酮合酶组装而成,而少数存在的具有特殊结构单元的聚酮案例给了研究者以灵感——通过设置和引入非天然结构单元从而有选择性地高效改造聚酮结构。聚酮骨架的生物合成有赖于一个起始单元与多个延伸单元的组装,因此,通过人工设计延伸单元向聚酮引入预期结构被认为是精准高效改造聚酮的有力突破点。本文在此总结了近十年来报道的聚酮非天然延伸单元的三种重要的酶促合成方法,通过挖掘新颖的延伸单元合成酶并探索其底物宽泛性,或利用酶工程手段改造延伸单元合成酶的底物催化范围,获得了大量自然界不存在的延伸单元。此外,本文还归纳了利用非天然延伸单元对聚酮结构进行改造的案例,借助聚酮的天然合成途径或利用改造的合成途径达到预期目的。最后,作者讨论了该研究领域内存在的一些制约因素以及可优化的研究方向,包括聚酮合酶对非天然延伸单元的兼容性问题、非天然延伸单元的前体供给等。近年来,利用非天然延伸单元改造聚酮结构的研究兴趣和热度日益高涨,本文绘制了一份基于延伸单元改造聚酮结构研究的简明清晰的图谱,期望为加速聚酮类药物的高效开发打下坚实基础。 展开更多
关键词 天然产物 聚酮化合物 聚酮合酶 延伸单元 生物合成 酶工程
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基于Fas/FasL信号通路对桂药生精胶囊治疗少精子症的临床研究
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作者 戴芳 唐亚平 +2 位作者 买鹏宇 张泽朝 朱闽 《检验医学与临床》 CAS 2024年第11期1543-1547,共5页
目的探讨桂药生精胶囊对少精子症(肾精亏虚型)患者的精子浓度(SC)、前向运动精子比例(PR)、PR+非前向运动精子比例(NP)、精子总数、精子脂肪酸合成酶(Fas)信使RNA(mRNA)、脂肪酸合成酶配体(FasL)mRNA表达水平及精浆Fas蛋白、FasL蛋白表... 目的探讨桂药生精胶囊对少精子症(肾精亏虚型)患者的精子浓度(SC)、前向运动精子比例(PR)、PR+非前向运动精子比例(NP)、精子总数、精子脂肪酸合成酶(Fas)信使RNA(mRNA)、脂肪酸合成酶配体(FasL)mRNA表达水平及精浆Fas蛋白、FasL蛋白表达水平的影响。方法选取2019年10月至2020年3月就诊于广西中医药大学附属瑞康医院男性科门诊的少精子症(肾精亏虚型)患者60例,随机分为对照组和治疗组,每组30例。对照组采用左卡尼汀治疗,治疗组在对照组的基础上联合桂药生精胶囊治疗,12周为1个疗程。观察治疗前后两组患者的SC、PR、PR+NP、精子总数、精子Fas mRNA、FasL mRNA和精浆Fas蛋白、FasL蛋白表达水平。结果治疗组总有效率比对照组高(P<0.05)。治疗前两组患者SC、PR、PR+NP和精子总数比较,差异均无统计学意义(P>0.05)。治疗后两组患者精子SC、PR、PR+NP和精子总数均比治疗前高(P<0.05),且治疗组患者精子SC、PR和精子总数高于对照组(P<0.05)。治疗前两组患者精浆Fas和FasL蛋白表达水平比较,差异均无统计学意义(P>0.05)。治疗后两组精浆Fas蛋白表达水平低于治疗前(P<0.05),且治疗组Fas蛋白表达水平低于对照组(P<0.05)。治疗前两组患者精子Fas mRNA和FasL mRNA表达水平比较,差异均无统计学意义(P>0.05)。治疗后两组患者精子Fas mRNA和FasL mRNA表达水平低于治疗前(P<0.05),且治疗组Fas mRNA表达水平低于对照组(P<0.05)。结论桂药生精胶囊能明显提高少精子症(肾精亏虚型)患者的SC、PR、精子总数,降低精子Fas mRNA及精浆Fas蛋白的表达水平。 展开更多
关键词 桂药生精胶囊 少精子症 肾精亏虚型 脂肪酸合成酶 脂肪酸合成酶配体
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醛固酮合成酶抑制剂治疗原发性醛固酮增多症的可行性探讨
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作者 董徽 左毓杰 蒋雄京 《中国循环杂志》 CSCD 北大核心 2024年第9期920-923,共4页
近年来,醛固酮合成酶抑制剂(aldosterone synthase inhibitor,ASI)治疗高血压受到广泛关注,osilodrostat、baxdrostat、lorundrostat和dexfadrostat等药物相继被研发并开展了一系列临床研究。本文拟对当前ASI治疗高血压的临床研究结果... 近年来,醛固酮合成酶抑制剂(aldosterone synthase inhibitor,ASI)治疗高血压受到广泛关注,osilodrostat、baxdrostat、lorundrostat和dexfadrostat等药物相继被研发并开展了一系列临床研究。本文拟对当前ASI治疗高血压的临床研究结果及存在的问题和争议进行阐述,并探讨ASI治疗原发性醛固酮增多症的可行性。 展开更多
关键词 原发性醛固酮增多症 醛固酮合成酶抑制剂 醛固酮
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基于血清iNOS和eNOS水平建立慢性阻塞性肺疾病急性加重患者机械通气撤机预测模型
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作者 郭志强 刘云峰 +2 位作者 高晓玲 李润杰 赵立春 《中国急救医学》 CAS CSCD 2024年第7期593-597,共5页
目的 基于血清诱导型一氧化氮合酶(iNOS)和内皮型一氧化氮合酶(eNOS)水平建立慢性阻塞性肺疾病急性加重(AECOPD)患者机械通气撤机的预测模型。方法 选择2020年1月至2023年6月在河北北方学院附属第一医院接受机械通气治疗的166例AECOPD患... 目的 基于血清诱导型一氧化氮合酶(iNOS)和内皮型一氧化氮合酶(eNOS)水平建立慢性阻塞性肺疾病急性加重(AECOPD)患者机械通气撤机的预测模型。方法 选择2020年1月至2023年6月在河北北方学院附属第一医院接受机械通气治疗的166例AECOPD患者,按照撤机结局分为撤机成功组(n=112)和撤机失败组(n=54)。比较两组患者的临床资料及入院时、自主呼吸试验(SBT)前的血清iNOS、eNOS水平。采用Logistic回归分析撤机失败的影响因素,采用受试者工作特征(ROC)曲线分析iNOS、eNOS预测撤机失败的价值。结果 与撤机成功组比较,撤机失败组SBT前24 h内的急性生理学与慢性健康状况评价Ⅱ(APACHEⅡ)评分、肌酐(Cr)、iNOS、eNOS水平较高,白蛋白(Alb)水平较低(P<0.05);多因素Logistic回归分析显示,APACHEⅡ、Alb、iNOS、eNOS是撤机失败的影响因素(P<0.05);ROC曲线分析显示,iNOS、eNOS预测撤机失败的ROC曲线下面积为0.648(95%CI 0.563~0.733,P=0.002)、0.755(95%CI 0.683~0.827,P<0.001),以4.418 ng/mL、3.821 ng/mL为最佳截断值,预测敏感度分别为68.52%、83.33%,特异度分别为51.82%、66.36%;iNOS、eNOS与Alb、APACHEⅡ联合预测撤机失败的ROC曲线下面积为0.961(95%CI 0.928~0.993),优于单一指标(Z=7.412、6.682、4.323、4.951,P<0.05),敏感度和特异度分别为94.44%和90.91%。结论 AECOPD患者SBT前血清iNOS、eNOS水平增加与撤机失败相关,SBT前检测iNOS、eNOS联合Alb、APACHEⅡ能够较好地预测撤机结局。 展开更多
关键词 慢性阻塞性肺疾病急性加重 机械通气 撤机失败 诱导型一氧化氮合酶
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