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生物样品中聚苯乙烯纳米塑料指示物的热裂解-气相色谱质谱检测方法研究

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环境卫生学杂志 2024年第6期14卷 501-507页

作者：谢颖李明姣杨波张少平董小艳王琼唐宋徐州医科大学公共卫生学院徐州221004 中国疾病预防控制中心环境与人群健康重点实验室/中国疾病预防控制中心环境与健康相关产品安全所北京100021 北京市顺义区疾病预防控制中心

目的采用热裂解-气相色谱质谱法(py-GC/MS)建立一种从生物组织样品中定量测定纳米级聚苯乙烯(PS)塑料的方法。方法通过比较和优化不同消解液、蛋白沉淀剂以及仪器检测参数体系,确定生物样品中PS塑料的最优前处理和检测方法。通过开展实... 详细信息

目的采用热裂解-气相色谱质谱法(py-GC/MS)建立一种从生物组织样品中定量测定纳米级聚苯乙烯(PS)塑料的方法。方法通过比较和优化不同消解液、蛋白沉淀剂以及仪器检测参数体系,确定生物样品中PS塑料的最优前处理和检测方法。通过开展实验研究确定方法特性指标(包括检出限、定量限、精密度和准确度),并基于方法开展了实际样品测定。结果本研究建立了大鼠肝和肺组织样本经10%氢氧化钾溶液消解和无水乙醇蛋白沉淀后上py-GC/MS检测的方法,PS在0.05~2.00μg范围内线性关系良好,相关系数为0.999,检出限和定量限分别为0.012和0.036μg/g,且当添加水平为低浓度(2μg/g)、中浓度(10μg/g)、高浓度(30μg/g)PS时,其加标回收率分别为68.0%~85.0%、80.0%~105%和62.0%~93.1%,精密度(RSD)范围在7.8%~15.2%。结论本研究建立的方法满足方法学要求,且为其他生物样本及其他类型微塑料的检测提供了参考,为进一步开展纳米塑料的人群内暴露水平研究和健康风险评估奠定了技术基础。

关键词：热裂解-气相色谱质谱法生物组织纳米塑料

不同授粉方式对连翘果实农艺性状和品质的影响

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中国野生植物资源 2024年第2期43卷 73-77,90页

作者：薛帼珍刘佳宁闫晓睿杨晓霞刘计权山西中医药大学中药与食品工程学院山西榆次030619 北京协和医学院药物研究所北京100050

目的:研究不同授粉方式对连翘果实农艺性状和主要药用成分含量的影响。方法:花期采用不同方式对连翘进行授粉,在青翘收获期测定结果率、果长、果宽、鲜重、干重、折干率等农艺性状指标和连翘酯苷A、连翘苷2个品质指标。结果:连翘♀长×... 详细信息

目的:研究不同授粉方式对连翘果实农艺性状和主要药用成分含量的影响。方法:花期采用不同方式对连翘进行授粉,在青翘收获期测定结果率、果长、果宽、鲜重、干重、折干率等农艺性状指标和连翘酯苷A、连翘苷2个品质指标。结果:连翘♀长×♂短异花授粉产生的果实农艺性状和含量最优;其余果实农艺性状和含量测定值由大到小依次为连翘♀短×♂长异花授粉、♀短×♂短(同型异花)授粉、♀长×♂长(同型异花)授粉,连翘自花授粉不结实;♀长×♂短异花授粉后的结果率、鲜重、干重、折干率、连翘酯苷A和连翘苷含量显著高于♀短×♂短(同型异花)授粉和♀长×♂长(同型异花)授粉。结论:连翘♀长×♂短异花授粉的果实农艺性状、连翘酯苷A和连翘苷含量最佳,可为连翘的规范化种植提供参考依据。

关键词：连翘授粉方式结果率连翘酯苷A 连翘苷

Crystalline-State Solvent:Metal-Organic Frameworks as a Platform for Intercepting Aggregation-Caused Quenching

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Chinese Journal of Chemistry 2022年第5期40卷 589-596页

作者： yan-Yuan Jia Jia-Cheng Yin Na Li Ying-Hui Zhang Rui Feng Zhao-Quan Yao Xian-He Bu School of Materials Science and Engineering Tianjin Key Laboratory of Metal and Molecule-Based Material ChemistryNankai UniversityTianjin300350 China State Key Laboratory of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin300071 China

The sequestration of organic luminescent molecules(OLMs)within cage-based metal-organic frameworks(MOFs)as a dispersion platform has been developed to impede aggregation-caused quenching(ACQ).The homogenous encapsulation of distinct luminescent guests of different sizes and emissive behaviors in the cage structure of a MOF resulted in high fluorescent quantum yields of 44.8%for DAPI@NKU-110(DAPI=4',6-diamidino-2-phenylindole),65.4%for TPPA@NKU-110(TPPA=tris(4-(pyridin-4-yl)phenyl)amine),31.3%for R6G@NKU-110(R6G=Rhodamine 6G),and 58.3%for py@NKU-110(py=pyronin Y),attributable to the confinement effect caused by the rigid cages of *** significantly,a positive correlation of the encapsulated quantity of OLMs with their concentration in the in-situ solvothermal reaction was unveiled by spectral analysis and utilized to facilely fabricate a white-light-emitting crystal material TPPA+R6G@*** material features a large crystal size on the millimeter-scale,broadband white emission,ideal CIE coordinates(0.33,0.34),and a high quantum yield(49.1%)when excited at 365 ***,such a strategy can be easily generalized to an abundance of other cage-based MOFs and a plentiful volume of OLMs for the future development of colorful,high performance luminescent materials.

关键词： Metal-organic frameworks Cage compounds Fluorescence Color tunability In-situ encapsulation

Advances in technologies for 3D genomics research

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Science China(Life Sciences) 2020年第6期63卷 811-824页

作者： yan Zhang Guoliang Li National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070China Agricultural Bioinformatics Key Laboratory of Hubei Province Hubei Engineering Technology Research Center of Agricultural Big DataCollege of InformaticsHuazhong Agricultural UniversityWuhan 430070China

The spatial structure of the orderly organized chromatin in the nucleus has important roles in maintaining normal cell function and in regulation of gene expression, and the high-throughput Hi-C and Ch IA-PET methods have been widely used in various biological studies for determining potential spatial genome structures and their functions. However, there are still great difficulties and challenges in three-dimensional(3D) genomics research. More efficient, economical, and unbiased approaches to studying 3D genomics need to be developed for more widespread and easier applications. Here, we review the most recent studies on new 3D genomics research technologies, such as improvements of the traditional Hi-C and Ch IA-PET methods, new approaches based on non-proximal-ligation strategies, and imaging-based methods improved in recent years. Especially, we review the CRISPR-based methods for functional validations in 3D genomics, which could be the forthcoming directions. We hope this review can show some insights into the potential improvements for future 3D genomics.

关键词： 3D genomics Hi-C Ch IA-PET FISH CRISPR

atg7 and beclin1 are essential for energy metabolism and survival during the larval-to-juvenile transition stage of zebrafish

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Aquaculture and Fisheries 2022年第4期7卷 359-372页

作者： Suzan Attia Mawed Jin Zhang Fan Ren yan He Jie Mei College of Fisheries Huazhong Agricultural UniversityWuhan430070China Zoology Department Faculty of ScienceZagazig UniversityZagazig44519Egypt

The high mortality in larval-to-juvenile transition is a big problem in aquaculture which is related to the shifting from endogenous to exogenous ***,the underlying causes remain poorly ***,an evolutionary regulated cellular mechanism,is highly conserved in eukaryotic organisms to maintain energy homeostasis against stress including *** investigate whether autophagy plays a role during larval-to-juvenile transition,we generated atg7 and beclin1 zebrafish mutant lines using CRISPR/Cas9 gene editing *** this study,both atg7 and beclin1 null zebrafish died during larval-to-juvenile transition because atg7 and beclin1 mutants were unable to cope with the metabolic stress after yolk absorption and fail to activate autophagy in response to nutrient ***,dramatic defects in the intestine architecture and metabolic functions in the liver of these mutants were observed even though refeeding *** with rapamycin,an activator of autophagy,could effectively extend the survival time of both atg7 and beclin1 null zebrafish through decreasing the metabolic rate while it couldn’t activate autophagy in mutants via the canonical ***,our results revealed that autophagy played a crucial role in zebrafish ontogeny during larval-to-juvenile transition,and it could be considered as one of the most important endogenous factors judging the survival rate of the developing embryos during this period.

关键词： Autophagy Larval-to-juvenile transition atg7 beclin1 Metabolism Rapamycin

去红衣与超声处理对花生油体提取及其乳化特性、抗氧化活性的影响

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中国油脂 2024年第1期49卷 22-28,42页

作者：曾广镇赵志浩周鹏飞邓媛元魏振承张雁唐小俊刘光李萍张名位天津科技大学食品科学与工程学院天津300457 广东省农业科学院蚕业与农产品加工研究所农业农村部功能食品重点实验室广东省农产品加工重点实验室广州510610

为了对花生油体的工业化提取和基于油体乳化体系新产品的开发提供参考,探究了去红衣与超声处理对花生油体提取及其乳化特性、抗氧化活性的影响。不同预处理的花生经水相提取,得到油体、清液和沉淀三相,测定了三相中固形物、脂肪、蛋白... 详细信息

为了对花生油体的工业化提取和基于油体乳化体系新产品的开发提供参考,探究了去红衣与超声处理对花生油体提取及其乳化特性、抗氧化活性的影响。不同预处理的花生经水相提取,得到油体、清液和沉淀三相,测定了三相中固形物、脂肪、蛋白质的含量和分布,并分析了油体的乳化特性、总酚与总黄酮含量以及抗氧化活性。结果表明:去红衣将脂肪在油体中的分布由63.36%提高至65.30%,与超声联合处理时进一步将其提高至68.13%;去红衣处理不利于花生油体的稳定性和抗氧化活性;与对照组相比,去红衣组油体乳液平均粒径由2510.00 nm上升至2953.67 nm,动力学稳定性降低;去红衣组油体总酚、总黄酮含量最低,分别为71.01μg/g与47.14μg/g;超声处理促进了花生油体的溶出,且提取的油体乳化稳定性和抗氧化活性最高,其乳液平均粒径为1742.00 nm,乳化活性指数和乳化稳定性指数分别为114.48 m^(2)/g与1848.40 min,动力学稳定性最佳,总酚、总黄酮含量分别为101.24μg/g与59.97μg/g。综上,去红衣处理有利于花生油体的提取,但会降低其稳定性与抗氧化活性,而超声处理不仅有利于花生油体的提取,还增强了其乳化稳定性和抗氧化活性。

关键词：花生去红衣超声油体乳液抗氧化活性

基于多谱学技术剖析“白转黑”发用产品功效成分

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分析测试学报 2024年第7期43卷 971-977页

作者：夏泽敏梁文耀黄敏涵贾芳陈彦君孙剑聂明霞席绍峰谭建华广州质量监督检测研究院广州市NQI-质量安全科技协同创新中心广东广州511447

组合采用色谱、质谱、光谱及能谱等分析技术,对“白转黑”发用产品中可能存在的功效成分进行筛查、鉴定和确认。采用高效液相色谱靶向筛查常见染发剂,气相色谱-质谱联用和超高效液相色谱-高分辨质谱非靶向筛查可能存在的染发和致黑成分... 详细信息

组合采用色谱、质谱、光谱及能谱等分析技术,对“白转黑”发用产品中可能存在的功效成分进行筛查、鉴定和确认。采用高效液相色谱靶向筛查常见染发剂,气相色谱-质谱联用和超高效液相色谱-高分辨质谱非靶向筛查可能存在的染发和致黑成分。在优化的筛查条件下,超高效液相色谱-高分辨质谱识别出样品放置72 h后m/z 147.930 9处的峰强度出现明显下降。结合精准质量数、同位素分布及保留时间推测该成分为银离子。采用电感耦合等离子体质谱、离子色谱对银元素和硝酸根离子进行含量测定并结合原料性质剖析其来源,同时利用低真空热场发射扫描电镜对产品变黑成分进行确认,推测硝酸银可能是“白转黑”发用产品产生功效的重要原因。基于硝酸银为功效成分的“白转黑”发用产品在合规性和安全风险方面存在较大问题,亟需对该类产品加强监管。该文建立的组合式分析模式将为后续深入开展化妆品安全风险剖析提供技术参考。

关键词： “白转黑”发用产品多谱学技术功效成分安全风险

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Metal Exposure and Risk of Diabetes and Prediabetes among Chinese Occupational Workers

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Biomedical and Environmental Sciences 2015年第12期28卷 875-883页

作者： yanG Ai Min CHENG Ning PU Hong Quan LIU Si Min LI Juan Sheng BASSIG bryan A. DAI Min LI Hai yan HU Xiao Bin REN Xiao Wei ZHENG Tong Zhang BAI Ya Na Institute of Epidemiology and Statistics School of Public HealthLanzhou University Department of Epidemiology School of Public HealthBrown University Center of Medical Laboratory Lanzhou University Workers’ Hospital of Jinchuan Group Co. Ltd. Department of Environmental Health Sciences School of Public HealthYale University Cancer Hospital Chinese Academy of Medical Sciences

Objective To study the association between metal exposure and risk of diabetes and prediabetes among Chinese workers exposed to *** We used data obtained from the baseline survey of the Jinchang Cohort Study of workers in Jinchang Industry,the largest nickel production company in China.A total of 42,122 workers ≥20 years of age were included in the study.A standardized,structured questionnaire was used to collect epidemiological *** examinations and laboratory tests were conducted to evaluate the health status of the participants and to measure various biomarkers including blood sugar,lipids,and urinary metal *** regression was used to study the association between occupational groups categorized according to the measured metal levels(office workers,low-level;mining/production workers,mid-level;and smelting/refining workers,high-level)and risk of diabetes and *** The overall prevalence of diabetes and prediabetes was 7.5% and 16.8%,*** adjusted odds ratios for diabetes among mining/production workers and smelting/refining workers compared to office workers were 1.5(95% CI:1.3,1.7)and 3.8(95% CI:3.4,4.3),*** association was observed between these occupational groups and prediabetes in this *** Occupations associated with higher levels of metal exposure were associated with an increased risk of diabetes in this *** studies are needed to confirm this observed association.

关键词： Metals Occupational exposure Diabetes Prediabetes Risk factors

Experimental investigation on the relevance of mechanical properties and porosity of sandstone after hydrochemical erosion

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Journal of Mountain Science 2016年第11期13卷 2053-2068页

作者： CAI yan-yan YU Jin FU Guo-feng LI Hong Fujian Research Center for Tunneling and Urban Underground Space Engineering Huaqiao University School of Civil and Hydraulic Engineering Dalian University of Technology

Under the effect of chemical etching,the macroscopic mechanical properties,mesoscopic structure,mineral content,and porosity of rocks undergo significant changes,which can lead to the geological disasters; thus,an understanding of changes in the microscopic and macroscopic structure of rocks after chemical etching is *** this study,uniaxial mechanical tests and nuclear magnetic resonance(NMR) spectroscopy were carried out on sandstone samples that had been previously subjected to chemical erosion under different p H *** aim was to study changes in properties and mechanical characteristics,including deformation and strength characteristics,of the rock,and microscopic pore variation characteristics,and to perform preliminary studies of the chemical corrosion *** show that different chemical solutions have a significant influence on the uniaxial compressive strength,the axial strain corresponding to the peak axial stress,elastic modulus,*** the passage of time,porosity increases gradually with exposure to different chemical solutions,and exposure to chemical solutions results in large changes in the NMR T2 curve and T2 spectrum *** exposed to different chemical solutions exhibits different corrosion mechanisms; the root cause is the change of mineral.

关键词：化学侵蚀砂岩样品力学特性孔隙度宏观力学性能单轴抗压强度实验核磁共振