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Changes in the Non-targeted Metabolomic Profile of Three-year-old Toddlers with Elevated Exposure to Polycyclic Aromatic Hydrocarbons
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作者 LI Yang LIN Dan +7 位作者 ZHANG Xiu Qin JU Guang Xiu SU Ya ZHANG Qian DUAN Hai Ping YU Wei Sen WANG Bing Ling PANG Shu Tao 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第5期479-493,共15页
Objective To investigate changes in the urinary metabolite profiles of children exposed to polycyclic aromatic hydrocarbons(PAHs)during critical brain development and explore their potential link with the intestinal m... Objective To investigate changes in the urinary metabolite profiles of children exposed to polycyclic aromatic hydrocarbons(PAHs)during critical brain development and explore their potential link with the intestinal microbiota.Methods Liquid chromatography-tandem mass spectrometry was used to determine ten hydroxyl metabolites of PAHs(OH-PAHs)in 36-month-old children.Subsequently,37 children were categorized into low-and high-exposure groups based on the sum of the ten OH-PAHs.Ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was used to identify non-targeted metabolites in the urine samples.Furthermore,fecal flora abundance was assessed by 16S rRNA gene sequencing using Illumina MiSeq.Results The concentrations of 21 metabolites were significantly higher in the high exposure group than in the low exposure group(variable importance for projection>1,P<0.05).Most of these metabolites were positively correlated with the hydroxyl metabolites of naphthalene,fluorine,and phenanthrene(r=0.336–0.531).The identified differential metabolites primarily belonged to pathways associated with inflammation or proinflammatory states,including amino acid,lipid,and nucleotide metabolism.Additionally,these distinct metabolites were significantly associated with specific intestinal flora abundances(r=0.34–0.55),which were mainly involved in neurodevelopment.Conclusion Higher PAH exposure in young children affected metabolic homeostasis,particularly that of certain gut microbiota-derived metabolites.Further investigation is needed to explore the potential influence of PAHs on the gut microbiota and their possible association with neurodevelopmental outcomes. 展开更多
关键词 Child Gut microbiota non-targeted metabolomics Polycyclic aromatic hydrocarbons Urinary metabolite profile
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Safety Evaluation of Myricetin and Crude Extract from Myrica rubra Leaves on Non-target Organisms
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作者 李桥 徐静 +2 位作者 张绍勇 张旭 陈安良 《Plant Diseases and Pests》 CAS 2010年第4期46-50,共5页
[ Objective] The study aimed to supply important basis for developing environment-friendly pesticides with myricetin and crude extract of Myrica rubra leaves as effective components. [ Method] According to "Test guid... [ Objective] The study aimed to supply important basis for developing environment-friendly pesticides with myricetin and crude extract of Myrica rubra leaves as effective components. [ Method] According to "Test guidelines for environmental safety evaluation on chemical pesticides", the toxicity of myricetin and crude extract of M. rubra leaves on non-target organisms was determined and the safety evaluation was carried out. [Result] MyriceUn and crude extract of M. rubra leaves had low toxicity on non-target organisms, such as earthworm, silkworm and soil microbes. Myricetin showed low toxicity and the crude extract of M. rubra leaves showed middle toxicity on tadpole. The high-concentration crude extract of M. rubra leaves had some antifeedant effect on silkworm. [ Conclusion] Myricetin and crude extract of M. rubra leaves had low toxicity on non-tar- get organisms in environment and they were relatively safe. 展开更多
关键词 MYRICETIN Crude extract of M. rubra leaves non-target organisms Safety evaluation
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Research and countermeasures on how to improve English parole competence of contemporary college students under non-target language environment
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作者 任重远 《Sino-US English Teaching》 2009年第4期15-22,共8页
Based on linguistic theories which developed by Saussure and some other contemporary linguists, this article attempts to analyze the factors that cause low English parole competence of the contemporary college student... Based on linguistic theories which developed by Saussure and some other contemporary linguists, this article attempts to analyze the factors that cause low English parole competence of the contemporary college students under non-target language environment. It views that how to properly deal with the relationship between langue and parole is still a debating focus in applied linguistics. The result of low English parole competence of contemporary college students is due to the interaction of the contemporary College English syllabus, text books pedagogies and the English language level of both students and teachers. Thus it puts forward some suggestions to improve the college students' English parole competence. 展开更多
关键词 non-target language environment college English teaching COUNTERMEASURE RESEARCH
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Effects of Transgenic Bt+CpTI Cotton on Field Abundance of Non-Target Pests and Predators in Xinjiang, China 被引量:10
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作者 XUYao WU Kong-ming +7 位作者 LI Hao-bing LIU Jian DING Rui-feng WANG Fei Ahtam Uwayis LI Hai-qiang WANG Dong-mei CHEN Xue-xin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第9期1493-1499,共7页
Transgenic insect-resistant cotton is being increasingly planted in Xinjiang cotton-planting regions, where geographical climate conditions and species composition of pests and natural enemies are greatly unique in Ch... Transgenic insect-resistant cotton is being increasingly planted in Xinjiang cotton-planting regions, where geographical climate conditions and species composition of pests and natural enemies are greatly unique in China. Limited studies have been conducted on the ecological impacts of transgenic insect-resistant cotton, especially for transgenic double genes (Bt+CpTI) cotton, in this region. In this study, the potential effects of transgenic Bt+CpTI cotton on the seasonal abundance of non-target pests and predators were assessed from 2009 to 2011 in Korla, Xinjiang. The results showed that species composition and seasonal abundance of 5 groups of pests and 5 groups of predators were not significantly different between transgenic Bt+CpTI cotton and non-transgenic cotton every year. It suggests that transgenic Bt+CpTI cotton per se does not affect the population dynamics of non-target pests and predators on this crop in Xinjiang. 展开更多
关键词 transgenic Bt+CpTI cotton non-target pests predators XINJIANG
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Impact Assessments of Transgenic cry1Ab Rice on the Population Dynamics of Five Non-Target Thrips Species and Their General Predatory Flower Bug in Bt and Non-Bt Rice Fields Using Color Sticky Card Traps 被引量:10
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作者 Akhtar Zunnu Raen YE Gong-yin +4 位作者 LU Zeng-bin CHANG Xue SHEN Xiao-jing PENG Yu-fa HU Cui 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第10期1807-1815,共9页
A 2-yr field study was conducted to assess the effects of transgenic japonica rice(KMD1 and KMD2) with a synthetic cry1 Ab gene from Bacillus thuingiensis Berliner on population dynamics and seasonal average densiti... A 2-yr field study was conducted to assess the effects of transgenic japonica rice(KMD1 and KMD2) with a synthetic cry1 Ab gene from Bacillus thuingiensis Berliner on population dynamics and seasonal average densities of five thrips species including Stenchaetothrips biformis(Bagnall),Frankliniella intonsa(Trybom),F.tenuicornis(Uzel),Haplothrips aculeatus(Fabricius),Haplothrips tritici(Kurd) and their general predatory flower bug,Orius similis Zheng as compared to the parental control rice line using the white,blue and yellow sticky card traps.Population dynamics and seasonal average densities of these five thrips species and their general predatory flower bug were not significantly affected by rice type.Additionally,the white sticky card trap was suggested to be the most suitable for monitoring the population of these five thrips species and their general predator.These results show that our tested Bt rice lines do not interrupt the population of non-target thrips species and their general predatory flower bug in the field,and also cannot result in more occurrence of these thrips species in the rice ecosystem. 展开更多
关键词 rice thrips predatory flower bug non-target effects Bt rice risk assessment
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Effect of Colored Sticky Cards on Non-target Insects 被引量:3
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作者 Zhen CHEN Yihang GE +1 位作者 Xia LIU Rongping KUANG 《Agricultural Science & Technology》 CAS 2015年第5期983-987,共5页
Field experiments to evaluate four different colored sticky cards for trapping non-target insects were conducted in an organic maize field in the Heinigou region of China. Yellow, blue, green, and red sticky cards wer... Field experiments to evaluate four different colored sticky cards for trapping non-target insects were conducted in an organic maize field in the Heinigou region of China. Yellow, blue, green, and red sticky cards were used to trap insects in the field. The total number of insects species caught was 54, with 3,862 individuals recorded. Over half of the specimens caught were non-target insects, including phytophagous insects, particularly dipteran species(including many mosquitoes)(50.3%), followed by target pests(37.0%), and beneficial insects(12.7%). Statistical analysis revealed a significant difference in attraction to target pests, non-target pests, and beneficial insects among treatment groups. The results showed that higher numbers of target pests(Myzus persicae Sulzer, Empoasca flavescens Fabricius, Nysius ericaecshinly Schilling) were caught on yellow sticky card traps compared with blue, green, or red sticky card traps, indicating that yellow was the best trap color for target pests, with green and blue being progressively less attractive. For non-target insects, including phytophagous insects, flies, and mosquitoes,higher numbers of were caught on blue sticky card traps compared with yellow,green, or red sticky card traps. Our study indicated that blue was the most attractive color for flies, especially for the housefly, Musca domestica Linnaeus. Our study also showed that most beneficial insects exhibited preferences to particular trap color characteristics: yellow was the most attractive color for parasitic wasps and lady beetles; blue was the most attractive color for hoverflies and honeybees. In contrast,green and red had no significant attraction to beneficial insects. 展开更多
关键词 Colored sticky cards Color trap non-target insects Beneficial insects Natural enemies Conservation
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Identification of key taste components in Baccaurea ramiflora Lour.fruit using non-targeted metabolomics 被引量:2
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作者 Jie Chen Fengnian Wu +7 位作者 Huachen Wang Chunce Guo Wengen Zhang Peisi Luo Jing Zhou Wenwen Hao Guangyao Yang Jianjian Huang 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期94-101,共8页
Among the numerous fruit species of Baccaurea ramiflora Lour.,‘LR’(white flesh)and‘BR’(pink flesh)are two kinds of local strains with high edibility.In order to study the metabolic causes of taste differences,we p... Among the numerous fruit species of Baccaurea ramiflora Lour.,‘LR’(white flesh)and‘BR’(pink flesh)are two kinds of local strains with high edibility.In order to study the metabolic causes of taste differences,we performed the non-targeted metabonomics analysis of‘LR’and‘BR’using LC-MS/MS.541 metabolites were totally identified,and 45 kinds of metabolites(carbohydrates,fatty acids,flavonoids and terpenoids,etc.)were different between the two strains.The results indicate L-sorbose,D-(+)-glucose,citric acid,L-phenylalanine and oleamide,α-eleostearic acid were the main primary metabolites.The significant difference existed in pathways of unsaturated fatty acids between the studied two strains by pathway enrichment analysis.The results demonstrate that the different in composition,as well as the abundance of primary and secondary metabolites may be the potential causes of taste differences,which provides a new insight into the possible metabolic factors setting off the changing taste of B.ramiflora. 展开更多
关键词 Baccaurea ramiflora TASTE Metabolites profiling non-targeted metabonomics analysis
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Non-target Screening and Quantitation of Organic Chlorides in Oilfield Chemicals with Comprehensive Two Dimensional Gas Chromatography Coupled with Time of Flight Mass Spectrometry 被引量:1
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作者 Zheng Kewen Guo Rui +5 位作者 Ren Guofa Xia Lingyan Xiong Wei Zhang Jin Chu Xiaodong Yu Zhiqiang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2017年第4期65-71,共7页
Advanced analytical methodology based on comprehensive two-dimensional gas chromatography-time of flight mass spectrometry(GC×GC-TOFMS) is proposed for investigation of organic chlorides in different oilfield che... Advanced analytical methodology based on comprehensive two-dimensional gas chromatography-time of flight mass spectrometry(GC×GC-TOFMS) is proposed for investigation of organic chlorides in different oilfield chemicals.The target screening was initially carried out on 8 suspected organic chlorides by evaluating the capability of the enhanced separation and reliable identification at a trace concentration. GC×GC-TOFMS allowed for the fast and automated analysis of organic chlorides at a level of 200 μg/L. This method was subsequently applied for non-target screening of organic chlorides in different oilfield chemicals at various locations across China. 22 organic chlorides were identified and verified by comparison with pure standards in the mixed sample. Finally, this method was used to determine the content of the organic chlorides in individual samples. The result showed that the organic chloride levels in 19 of the 39 tested oilfield chemicals were above the threshold limit of 1.0 mg/L. 展开更多
关键词 GC×GC-TOFMS non-target SCREENING OILFIELD chemicals organic chlorides QUANTITATION
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Non-target-site and target-site resistance to AHAS inhibitors in American sloughgrass(Beckmannia syzigachne) 被引量:2
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作者 WANG Jing-jing LI Xiang-ju +4 位作者 LI Dan HAN Yu-jiao LI Zheng YU Hui-lin CUI Hai-lan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第12期2714-2723,共10页
American sloughgrass(Beckmannia syzigachne(Steud.) Fernald) is one of the most competitive and malignant weeds in rice-wheat rotation fields in China. American sloughgrass populations in the Jiangsu Province of China ... American sloughgrass(Beckmannia syzigachne(Steud.) Fernald) is one of the most competitive and malignant weeds in rice-wheat rotation fields in China. American sloughgrass populations in the Jiangsu Province of China became less sensitive to acetohydroxyacid synthase(AHAS) inhibitors after repeated application for many years in these areas. Two suspected resistant American sloughgrass populations(R1 and R2) collected in the field were detected the resistance to inhibitors of AHAS in whole-plant dose-response assays, compared to the susceptible(S) population. These assays indicated that R1 showed low resistance to mesosulfuron-methyl(3.32-fold), imazapic(2.84-fold) and pyroxsulam(1.55-fold), moderate resistance to flazasulfuron(4.67-fold) and pyribenzoxim(7.41-fold), and high resistance to flucarbazone(11.73-fold). However, using a combination of the cytochrome P450 inhibitor, malathion, with mesosulfuron-methyl resulted in a reduction in R1 resistance relative to mesosulfuron-methyl alone. Furthermore, R2 was highly resistant to flazasulfuron(34.90-fold), imazapic(11.30-fold), flucarbazone(49.20-fold), pyribenzoxim(12.94-fold), moderately resistant to mesosulfuron-methyl(9.77-fold) and pyroxsulam(6.26-fold), and malathion had no effect on R2 resistance to mesosulfuron-methyl. The fulllength of AHAS genes was sequenced and the AHAS enzymes were assayed in vitro in order to clarify the mechanism of resistance to AHAS inhibitors in R1 and R2 populations. The results demonstrated that R2 had a Pro-197-Ser mutation in the AHAS gene, and the sensitivity of R2 to the five AHAS inhibitors was decreased, which may result in R2 resistance to AHAS inhibitors. There was no mutation in the AHAS gene of R1, and there were no significant differences in enzyme sensitivity between susceptible(S) and resistant(R1) populations. An enhanced metabolism may be the main mechanism of R1 resistance to AHAS inhibitors. 展开更多
关键词 American sloughgrass CROSS-RESISTANCE gene mutation non-target-site resistance
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Non-target lung embolization during portal vein embolization due to an unrecognized portosystemic venous fistula:A case report
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作者 Sultan R Alharbi Mohammed Bin Nasif Haifa Bandar Alwaily 《World Journal of Clinical Cases》 SCIE 2023年第15期3625-3630,共6页
BACKGROUND Portal vein embolization(PVE)is an effective and relatively safe procedure performed prior to major hepatic resection to enhance future liver remnant.Nontarget embolization during PVE is rare,and if it occu... BACKGROUND Portal vein embolization(PVE)is an effective and relatively safe procedure performed prior to major hepatic resection to enhance future liver remnant.Nontarget embolization during PVE is rare,and if it occurs,it usually affects the future liver remnant.Intrahepatic portosystemic venous fistulas are extremely rare in non-cirrhotic livers.We report a case of non-targeted lung embolization during PVE due to an unrecognized intrahepatic portosystemic fistula.CASE SUMMARY A 60-year-old male presented with metastatic colon cancer of the liver.The patient underwent preoperative right PVE.During the embolization procedure,a small amount of glue and lipiodol emulsion was embolized to the heart and lungs through an unrecognized intrahepatic portosystemic fistula.The patient remained clinically stable and underwent the planned hepatic resection after 4 wk,with an uneventful postoperative course.CONCLUSION Conventional portograms and careful evaluation prior to PVE are advisable to avoid such complications. 展开更多
关键词 Portal vein embolization non-target embolization Portosystemic venous fistula Case report
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Analysis of Differential Metabolites in Selenium-enriched Rice Based on Extensive Non-targeted Metabolome
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作者 Biaojin ZHANG Xiaoyu CHANG +2 位作者 Tianhua TU Xiangxi ZHANG Tingcan DAI 《Agricultural Biotechnology》 CAS 2023年第3期101-105,112,共6页
[Objectives]Selenium(Se)-enriched rice is the main type of Se-enriched agricultural product developed in China,and this study aimed to understand the impact of selenium application on the metabolites in rice.[Methods]... [Objectives]Selenium(Se)-enriched rice is the main type of Se-enriched agricultural product developed in China,and this study aimed to understand the impact of selenium application on the metabolites in rice.[Methods]Se-enriched rice was prepared by foliar application of a sodium selenite aqueous solution,and high-throughput analysis of differential metabolites in Se-enriched rice was conducted based on extensive non-targeted metabolome.[Results]There were significant differences in metabolites between Se-enriched rice and ordinary rice,and a total of 535 differential metabolites were identified.Among them,420 metabolites in Se-enriched rice were upregulated,accounting for 78.5%,far higher than downregulated metabolites.The enrichment differences of three KEGG metabolic pathways,including cysteine and methionine metabolism,zeatin biosynthesis,and arachidonic acid metabolism,reached a significant level,indicating that selenium enrichment had a significant regulatory effect on the metabolism of sulfur-containing amino acids,the synthesis of natural cytokinin zeatin,and arachidonic acid bioactive components in rice.[Conclusions]The results can provide a theoretical basis for the production of Se-enriched rice. 展开更多
关键词 RICE Selenium non-targeted metabolome Differential metabolites
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Thrips-mediated impacts from transgenic rice expressing Cry1Ab on ecological fitness of non-target predator Orius tantilus(Hemiptera:Anthocoridae)
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作者 Akhtar Zunnu Raen DANG Cong +2 位作者 WANG Fang PENG Yu-fa YE Gong-yin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第9期2059-2069,共11页
Various rice lines have been genetically modified with genes from Bacillus thuringiensis(Bt) to continuously produce Bt insecticidal proteins against lepidopteran larvae. The Bt insecticidal protein constantly expre... Various rice lines have been genetically modified with genes from Bacillus thuringiensis(Bt) to continuously produce Bt insecticidal proteins against lepidopteran larvae. The Bt insecticidal protein constantly expresses in the plants to create an opportunity for non-target herbivores to acquire and convey the protein to their predators or parasitoids across trophic levels. This paper evaluates the effects of Bt rice(namely, Kemindao 1(KMD1) and Kemindao 2(KMD2)) expressing Cry1 Ab as compared to its non-Bt control line, Xiushui 11 on non-target predator Orius tantilus(a generalist predatory anthocorid of thrips) under laboratory and field conditions. To measure several biological parameters such as total nymphal duration and fecundity of this bug, it was reared on thrips and pollens of KMD1 and KMD2 as compared to their control under laboratory conditions. By comparison with the control, Bt rice did not significantly affect main life-history characteristics(total nymphal duration, female adult longevity, oviposition period and fecundity) of this anthocorid preying on Bt rice-fed thrips along with Bt rice pollens, except that the fecundity of this predator for KMD1 was distinctly lower as compared with KMD2 or the control. Enzyme-linked immunosorbent assay(ELISA) results showed that no Cry1 Ab protein was detected in this predator fed on thrips or rice pollen from Bt rice but was in Bt rice pollens. With the beat plate, plastic bag and color trap sampling methods, two-year field monitoring of O. tantilus abundance demonstrated that Bt rice had no significant detrimental effects on the population dynamics and seasonal average densities of this predatory anthocorid as compared with the control. Thus, it is suggested that growing our tested Bt rice(KMD1 and KMD2) producing Cry1 Ab will pose a negligible risk to the anthocorid, O. tantilus. 展开更多
关键词 Orius tantilus Btrice Cry1Ab risk assessment non-target effects
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Semi-volatile organic compounds in a museum in China:A non-targeted screening approach
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作者 SONG ZiDong NIAN LuYing +9 位作者 SHI Meng REN XiaoPeng TANG Ming SHI AnMei HAN Ying LIU Min WANG LuYang ZHANG YinPing XU Ying FENG XiaoMeng 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2024年第9期2693-2705,共13页
Non-targeted analysis(NTA)was conducted to identify semi-volatile organic compounds(SVOCs)in a museum in China using the gas chromatography(GC)-Orbitrap-mass spectrometer(MS).Approximately 160 SVOCs were detected,of w... Non-targeted analysis(NTA)was conducted to identify semi-volatile organic compounds(SVOCs)in a museum in China using the gas chromatography(GC)-Orbitrap-mass spectrometer(MS).Approximately 160 SVOCs were detected,of which 93 had not been reported in previous studies of museum environments.Many of the detected SVOCs were found to be associated with the chemical agents applied in conservation treatment and the materials used in furnishings.The results of hierarchical cluster analysis(HCA)indicated a spatial variation of SVOCs in the indoor air in the museum,but there were no obvious temporal differences of SVOCs observed in indoor dust.Spearman's correlation analysis showed that several classes of SVOCs were well correlated,suggesting their common sources.Fragrances and plasticizers were found to be the primary sources of SVOC pollution detected in the museum.Compared with compounds in outdoor air,indoor SVOCs had a lower level of unsaturation and more portions of chemically reduced compounds.This study is the first of its kind to comprehensively characterize SVOCs in a museum using an automated NTA approach with GC-Orbitrap-MS.The SVOCs identified in the current study are likely to be present in other similar museums;therefore,further examination of their potential impacts on cultural heritage artifacts,museum personnel,and visitors may be warranted. 展开更多
关键词 non-target analysis high-resolution mass spectrometry semi-volatile organic compounds museum environment air pollutants
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非靶向代谢组学揭示宫颈癌发展进程的特征代谢谱研究
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作者 翟青枝 马韵之 +5 位作者 叶明侠 王铭洋 李阳 李莉 孟元光 李立安 《中国病理生理杂志》 北大核心 2025年第2期230-238,共9页
目的:探讨宫颈病变过程中的代谢谱差异及其用于辅助诊断宫颈癌的潜在临床价值。方法:采用超高效液相色谱串联高分辨率质谱分析技术,对43例宫颈癌患者,34例高级别鳞状上皮内病变患者和43例健康对照人群的宫颈拭子样本进行了非靶向代谢组... 目的:探讨宫颈病变过程中的代谢谱差异及其用于辅助诊断宫颈癌的潜在临床价值。方法:采用超高效液相色谱串联高分辨率质谱分析技术,对43例宫颈癌患者,34例高级别鳞状上皮内病变患者和43例健康对照人群的宫颈拭子样本进行了非靶向代谢组学分析。在三组代谢谱均有明显特征的基础上,利用主成分分析法确定健康对照,高级别鳞状上皮内病变与宫颈癌之间的代谢差异,并使用Metabo Analyst 5.0对显著差异代谢物进行了KEGG通路富集分析。最后,通过随机森林机器学习构建区分宫颈癌与健康对照,高级别鳞状上皮内病变与健康对照和宫颈癌与高级别鳞状上皮内病变人群的分类预测模型,并通过ROC曲线评估模型效能。结果:健康对照、高级别鳞状上皮内病变和宫颈癌3组经过滤后共得到1543种代谢物,其中包含407个组间差异代谢物。研究发现内源代谢物PGE2同时存在于3组中,且其表达水平随宫颈病变的发展呈现逐步上升状态。差异代谢物富集分析显示宫颈癌具有特异的癌症相关代谢通路,包括三羧酸循环、酪氨酸代谢、色氨酸代谢、戊糖磷酸代谢等。研究基于代谢产物构建了3种可用于辅助诊断高级别鳞状上皮内病变和宫颈癌的预测模型,即全模型、简化模型和PGE2模型。结果表明代谢物具有良好的诊断效能,其中全模型及简化模型均可有效区分宫颈癌与高级别鳞状上皮内病变,宫颈癌与健康人群,以及高级别鳞状上皮内病变与健康人群。前者AUC值分别达到了0.90、0.92和0.84,后者AUC值分别达到了0.81、0.95和0.85。PGE2模型区分宫颈癌与健康对照,高级别鳞状上皮内病变与健康对照的AUC值分别是0.74和0.80。结论:宫颈癌的不同发展进程其代谢谱具有显著差异,且这些代谢物有成为宫颈病变生物标志物的潜在临床价值。 展开更多
关键词 宫颈癌 高级别鳞状上皮内病变 宫颈拭子 代谢谱 非靶向代谢组学
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自发性高血压大鼠的中医证型特点及其代谢物质基础研究
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作者 张秋菊 王宇 +7 位作者 凌必时 司美龙 孟浩先 田萌媛 张铭 连妮妮 康万荣 金华 《中国实验动物学报》 北大核心 2025年第1期44-53,共10页
目的探究自发性高血压大鼠(spontaneously hypertensive rat,SHR)的中医证型特点及可能的代谢物质基础。方法10周龄SPF级SHR及同品系同周龄WKY大鼠,分SHR组和WKY组,每组8只大鼠。通过综合动态观察和检测SHR的一般状态、性情、周围血管... 目的探究自发性高血压大鼠(spontaneously hypertensive rat,SHR)的中医证型特点及可能的代谢物质基础。方法10周龄SPF级SHR及同品系同周龄WKY大鼠,分SHR组和WKY组,每组8只大鼠。通过综合动态观察和检测SHR的一般状态、性情、周围血管充盈度、舌象、饮食饮水量、尿量、粪便量与性状、血压、心率、呼吸频率、痛阈和旷场实验,以辨别其可能的中医证型。同时,利用液相色谱串联质谱技术(liquid chromatography tandem-mass spectrometry,LC-MS/MS)对血清代谢物进行非靶向检测分析,以初步揭示引起血压升高和中医证型表现的物质基础。结果与WKY组相比,SHR组大鼠毛色暗黄、易激惹程度及周围毛细血管充盈评分较高(P<0.0001);舌色赤红,舌质干、津液少;24 h饮食饮水量及尿量、粪便量少(P<0.05),粪便含水率较低(P<0.001);收缩压(systolic blood pressure,SBP)、舒张压(diastolic blood pressure,DBP)、平均动脉压(mean arterial pressure,MAP)、心率(heart rate,HR)、呼吸频率(respiratory rate,RR)均明显较高(P<0.05);痛阈较低(P<0.0001);旷场实验显示,边缘运动距离和停留时间较长(P<0.001)。血清非靶向代谢组学结果显示,与WKY组相比,SHR组大鼠具有显著性差异的代谢物共有114种(P<0.05),这些差异代谢物主要为脂质和类脂分子(40.35%)、有机酸及其衍生物(22.8%)、有机杂环化合物(15.79%)。差异代谢物通过京都基因与基因组百科全书(kyoto encyclopedia of genes and genomes,KEGG)数据库富集分析共得到25条代谢通路,进一步差异丰度得分分析,其中16条通路被激活,仅4条通路被抑制,5条通路未见明显变化;而其中与神经系统兴奋性相关的3条通路中,谷氨酸能突触(glutamatergic synapse)和γ-氨基丁酸能突触(GABAergic synapse)被激活,而5-羟色胺能突触(serotonergic synapse)则被抑制。结论SHR有急躁易怒、周围血管扩张侧支循环形成、球结膜充血膨出、舌色赤红,舌质干、便秘、小便少而赤黄、心率、呼吸频率增快等表现,这些均提示SHR表现为高血压肝阳上亢证,其物质基础除了与脂类、氨基酸、碳水化合物代谢增强有关外,还可能与谷氨酸能、γ-氨基丁酸能及血清素能等神经通路代谢紊乱有关。 展开更多
关键词 高血压 病证结合动物模型 自发性高血压大鼠 肝阳上亢证 非靶向代谢组
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剁辣椒源益生菌筛选及其在发酵剁辣椒中的应用
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作者 杨倩 肖路遥 +2 位作者 白旭红 田玉芳 李伟 《食品工业科技》 北大核心 2025年第3期178-187,共10页
为开发风味优良且具有一定营养健康功效的益生菌发酵剁辣椒,本研究以湖南传统发酵剁辣椒为原料,筛选耐受胃肠消化的益生菌进行剁辣椒发酵,通过理化分析、感官评价及非靶向代谢组学技术,探究益生菌发酵对剁辣椒理化性质、安全性和感官特... 为开发风味优良且具有一定营养健康功效的益生菌发酵剁辣椒,本研究以湖南传统发酵剁辣椒为原料,筛选耐受胃肠消化的益生菌进行剁辣椒发酵,通过理化分析、感官评价及非靶向代谢组学技术,探究益生菌发酵对剁辣椒理化性质、安全性和感官特性的影响。结果表明,筛选得到3株耐受胃肠消化菌株,鉴定为植物乳植杆菌(Lactiplantibacillus plantarumJEB2)、短乳杆菌(Lactobacillus brevisJEB7)和酿酒酵母(Saccharomyces cerevisiae JEE2)。其中L.plantarum JEB2和L.brevis JEB7在24 h内将0.25 mg/mL亚硝酸钠全部降解,S.cerevisiae JEE2在24 h内胆固醇同化率达50.79%;筛选菌种发酵制备的剁辣椒pH<4.2、滴定酸度>0.6%,样品亚硝酸盐含量及大肠菌群明显低于自然发酵剁辣椒;L.plantarum JEB2和L.brevis JEB7复配发酵制备的剁辣椒样品感官得分最高为19.50(满分20),非靶向代谢组学结果显示该剁辣椒样品刺激性物质(4-乙酰氨基-2-氨基丁酸和巴豆苷)表达量下调,芳香物质(4-甲基苯甲醛、黄铜酸乙烯酯、D-山梨醇等)和活性物质(笑脸素、鹅膏苷F5、白花丹等)表达量上调。因此,利用L.plantarum JEB2和L.brevis JEB7发酵剁辣椒,可以降低产品刺激性、增加风味,并提高产品安全性和益生特性,可进一步开发利用作为发酵产品的生产发酵剂。 展开更多
关键词 剁辣椒 益生菌 发酵 非靶向代谢组学 感官评价
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城市环境下智能反射面辅助雷达非视距检测
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作者 杨鹏 周宇 +2 位作者 张宇佳 张哲昊 张世哲 《西安电子科技大学学报》 北大核心 2025年第1期130-141,共12页
雷达非视距目标探测是城市环境下的一个重要问题,建筑物等障碍在雷达与目标之间形成遮挡导致雷达检测性能受限,传统方法是利用电磁波在墙体等介质表面的反射来实现对盲区内目标的有效探测,然而电磁波在墙体处和传播过程中的衰减限制了... 雷达非视距目标探测是城市环境下的一个重要问题,建筑物等障碍在雷达与目标之间形成遮挡导致雷达检测性能受限,传统方法是利用电磁波在墙体等介质表面的反射来实现对盲区内目标的有效探测,然而电磁波在墙体处和传播过程中的衰减限制了探测范围。可重构智能表面是一种在空域能够将电磁波反射并实现能量聚焦的平面阵列,由低功耗的电子电路控制,通过调控元件反射系数可将信号聚焦于不同位置,智能反射面凭借其低成本、易部署、低功耗的优势能够广泛应用于城市环境中。受到智能反射面调控信号能力的启发,提出利用智能反射面辅助雷达非视距探测的方法,将信号转发至目标处从而绕过遮挡,并采用交替优化算法求解反射系数,旨在提高雷达在非视距场景下的目标检测性能,拓宽雷达在城市环境下的应用。仿真实验结果表明,相比传统方法智能反射面辅助雷达非视距目标探测范围得到提升,并且智能反射面增加元件数,位置布置靠近雷达端或目标处时检测性能能够得到增强。 展开更多
关键词 非视距 目标探测 可重构智能表面 交替优化
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2种云南特色小米辣果实成熟过程中代谢物比较分析
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作者 胡华冉 钟秋月 +4 位作者 杜磊 张芮豪 李卫芬 刘发万 桂敏 《热带作物学报》 北大核心 2025年第2期343-358,共16页
辣椒及其制品以其独特的风味深受各国人民喜爱,而代谢物质的组成及其含量对辣椒风味品质有重要影响。小米辣是云南区域性特色辣椒品种,因其营养成分丰富、辣味香浓深受消费者青睐。为了探明不同栽培种云南特色小米辣果实在成熟过程中代... 辣椒及其制品以其独特的风味深受各国人民喜爱,而代谢物质的组成及其含量对辣椒风味品质有重要影响。小米辣是云南区域性特色辣椒品种,因其营养成分丰富、辣味香浓深受消费者青睐。为了探明不同栽培种云南特色小米辣果实在成熟过程中代谢产物和代谢途径的异同,本研究以绿熟期和红熟期云南本地传统小米辣(Capsicum frutescens L.)和晶翠(C. baccatum L.)小米辣果实为研究对象,借助非靶向代谢组技术揭示2种小米辣果实在不同生育期的代谢物变化和代谢途径差异。结果表明:在云南小米辣中共鉴定出12类880个代谢产物,其中脂类、有机酸类占比最高,表明云南小米辣营养物质丰富,可以作为一种潜在的功能性食品原料。差异代谢物的种类、数量因生育期、品种差异出现显著不同,但小米辣红熟果较绿熟果的营养物质更丰富;2种栽培种相比,云南本地小米辣中的黄酮类物质较丰富,而晶翠中的氨基酸数量、种类更多。从不同比较组筛选出特有差异代谢物,黄酮类、甘油磷脂类、氨基酸类等物质可作为2种栽培种在不同生育期的潜在生物标志。KEGG富集分析发现包含了常见代谢物的代谢通路(脂质、氨基酸、糖类、碳水化合物、次生代谢产物、萜类和多酮类等),小米辣在2个生育期的关键代谢通路主要富集在甘油磷脂代谢通路、黄酮和黄酮醇生物合成、植物次生代谢产物的生物合成、苯丙素的生物合成,并找到不同比较组特有差异代谢通路。综上,2种小米辣果实代谢物种类、数量差异显著且独具特色,本研究结果为小米辣风味品质育种及后期采收策略提供数据支持。 展开更多
关键词 小米辣 不同生育期 非靶向代谢组 差异代谢物 代谢途径
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基于非中心逆威沙特分布的非线性扩展目标跟踪方法
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作者 陈辉 王秋菊 +1 位作者 彭天曙 赵永红 《兰州理工大学学报》 北大核心 2025年第1期100-107,共8页
针对非线性扩展目标跟踪问题,提出了在非中心逆威沙特分布条件下的非线性扩展目标跟踪方法.首先,在贝叶斯滤波框架下采用非中心逆威沙特分布进行算法的迭代,避免了因矩匹配或KL散度最小化而导致的信息丢失.其次,考虑到传统随机矩阵(RM)... 针对非线性扩展目标跟踪问题,提出了在非中心逆威沙特分布条件下的非线性扩展目标跟踪方法.首先,在贝叶斯滤波框架下采用非中心逆威沙特分布进行算法的迭代,避免了因矩匹配或KL散度最小化而导致的信息丢失.其次,考虑到传统随机矩阵(RM)模型只能在线性观测条件下应用,利用去相关无偏转换量测将极坐标系下的非线性量测信息进行线性化处理,保证了量测转换的无偏性以及避免转换后的量测协方差估计与量测噪声的相关性,从而最终推导得到在非中心逆威沙特分布下非线性扩展目标跟踪的有效算法.椭圆形扩展目标的跟踪仿真实验验证了所提方法的有效性. 展开更多
关键词 扩展目标跟踪 随机矩阵 非中心逆威沙特分布 非线性量测
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茉莉酸甲酯诱导马尿泡根系分泌物的差异含量及分析
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作者 孟静 叶星 +7 位作者 林鹏程 杜和艳 胡星强 曹雪叶 王环 师生波 沈建伟 周党卫 《广西植物》 北大核心 2025年第1期172-184,共13页
马尿泡是一种濒危高山植物,产于青藏高原,托烷类生物碱为其主要活性成分。马尿泡的根、种子和全草都可入药,具有重要的药用价值。为探究茉莉酸甲酯诱导下马尿泡根系分泌物的变化,该研究采用LC-MS/MS非靶向代谢组学技术对0、150μmol... 马尿泡是一种濒危高山植物,产于青藏高原,托烷类生物碱为其主要活性成分。马尿泡的根、种子和全草都可入药,具有重要的药用价值。为探究茉莉酸甲酯诱导下马尿泡根系分泌物的变化,该研究采用LC-MS/MS非靶向代谢组学技术对0、150μmol·L^(-1)茉莉酸甲酯处理3 d和7 d的马尿泡根系分泌物进行了分析。结果表明:(1)在0、150μmol·L^(-1)茉莉酸甲酯处理3 d和7 d后,马尿泡根系分泌物含量具有明显差异。(2)与空白处理相比,150μmol·L^(-1)茉莉酸甲酯处理后,根系分泌物数量明显增加。(3)马尿泡根系分泌物主要参与的KEGG通路有α-亚麻酸代谢通路、植物激素信号转导通路和赖氨酸生物合成通路。综上认为,茉莉酸甲酯诱导影响了马尿泡根系的代谢,改变了马尿泡根系分泌物的含量和数量。该研究通过非靶向代谢组学分析,初步揭示了参与马尿泡根系应答茉莉酸甲酯诱导分泌的关键代谢物,为进一步了解在茉莉酸甲酯诱导下高山植物根系分泌物的变化和代谢机制提供了理论依据,也为马尿泡资源的可持续发展和空间提供了新思路。 展开更多
关键词 马尿泡 根系分泌物 茉莉酸甲酯 非靶向代谢组学 代谢途径
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