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[Current advances in the analysis of free RNA modified nucleosides by high performance liquid chromatography-tandem mass spectrometry]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 3-12页

作者： Lyu-Ye Zhang Wei-Bing Zhang Hai-Lin Wang State Key Laboratory of environmental Chemistry and ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China. Shanghai Key Laboratory of Functional Materials Chemistry School of Chemistry & Molecular Engineering East China University of Science and Technology Shanghai 200237 China. State Key Laboratory of environmental Chemistry and ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China 3. University of Chinese Academy of sciences Beijing 100049 China. University of Chinese Academy of sciences Beijing 100049 China.

Post-transcriptional ribonucleic acid (RNA) modifications play crucial roles in regulating gene expression, with both eukaryotic and prokaryotic RNA exhibiting more than 170 distinct and ubiquitous modifications. RNA turnover generates numerous free nucleosides, including unmodified nucleosides and a variety of modified ones. Unlike unmodified nucleosides, modified nucleosides are not further degraded or used in the salvage-synthesis pathway owing to a lack of specific enzymes, which leads to the cytosolic accumulation or cellular efflux of modified nucleosides. These modified nucleosides can act as signaling molecules that regulate downstream pathways once transported to the extracellular space; alternatively, they are metabolized in the bloodstream and excreted in urine. Metabolized modified nucleosides are altered by cellular stress responses and mediate abnormal physiological states. Changes in the urinary and blood levels of modified nucleosides associated with cancer can serve as biomarkers for disease. Therefore, identifying and accurately quantifying nucleosides is vital for understanding RNA degradation and associated patterns of nucleoside metabolism. Such analyses are helpful when studying the biological functions and potential clinical applications of modified nucleosides. In this regard, high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) offers significant advantages in terms of sensitivity, selectivity, and efficiency, and has been widely used to analyze DNA and RNA nucleosides/nucleotides and their analogues. Multiple MS detection patterns and quantification methods have been established to detect nucleosides in biological samples, including cultured cells, urine, blood, and tissue samples. However, the development of an accurate HPLC-MS/MS method faces several challenges. Firstly, the presence of a complex biological matrix that contains macromolecules, small molecules, and salts can interfere with analysis. Salts and co-elu

关键词： RNA modifications high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) metabolite analysis methylated nucleosides

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[Determination of 12 halogenated organic pollutants in edible fish by ultra performance liquid chromatography-high resolution mass spectrometry combined with ultrasound-assisted extraction and gel permeation chromatography purification]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 68-77页

作者： Yi-Zhe Zhu Rui-Fen Zheng Zi-Hao Fan Ling Liu Jing-Yao Ye Kai Wang Cai-Ming Tang research center for eco-environmental Engineering Dongguan University of Technology Dongguan 523808 China. Guangdong Key Laboratory of environmental Resources Utilization and Protection Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China.

Halogenated organic pollutants (HOPs) have attracted considerable attention owing to their persistence, bioaccumulation, and toxicity. The development of methods to detect HOPs in fish is challenging owing to the compositional complexity of fish matrices, which contain high levels of lipids and relatively low concentrations of HOPs. In addition, the lipophilicity of most HOPs renders their extraction difficult. Moreover, the simultaneous determination of multiple HOPs to achieve the high-throughput screening of these analytes is complex. In this study, a reliable and efficient pretreatment method based on ultrasound-assisted extraction, gel permeation chromatography purification, and ultra performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS) was developed for the determination of 12 HOPs in edible fish. The procedures of sample extraction and purification and LC-HRMS detection parameters were optimized to improve the performance of the method. Fresh fish samples were thoroughly rinsed with water, and non-edible parts, including the skin, bones, and phosphorus, were removed. The fish were weighed, cut into small pieces, and vacuum freeze-dried for 48 h. Subsequently, a freeze grinder was used to grind the dried fish into a fine powder. Exactly 2 g of the fish powder was weighed, fortified with isotope-labeled internal standards of the HOPs, and allowed to stand for 5 min. Methanol-acetonitrile (1∶1, v/v) was then added, followed by vortex mixing and ultrasonication. After centrifugation, the supernatant was transferred to a fresh tube. The extraction process was repeated twice and all extracts were combined. The extract was evaporated under a gentle nitrogen flow and redissolved in a mixture of ethyl acetate-cyclohexane (1∶1, v/v). The sample mixture was cleaned using gel permeation chromatography, and the eluate was collected and concentrated under a nitrogen flow. Sample residuals were reconstituted with water-methanol (1∶1, v/v) prior to

关键词： edible fish gel permeation chromatography (GPC) halogenated organic pollutants (HOPs) ultra performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS)

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EFFECTS OF DDT AND BHC ON AMINO ACID CONTENT AND ITS VARIETIES IN CHLORELLA VULGARISBEU. AND CLADOPHORA SP.

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Chinese Journal of Oceanology and Limnology 1991年第1期9卷 57-63页

作者：林毅雄 research center for eco-environmental sciences Academia Sinica Beijing 100083

In Chlorella vulgaris Beg. and Cladophora sp. treated with different concentrations of r-BHC and p,p-DDT, the protein and free amino acid content in both were higher than those in the controls, and the free amino acid... 详细信息

关键词： Chlorella vulgaris algae ACID wastewater methionine illumination histidine Tianjin algal

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[Construction of a 17 β-estradiol sensor based on a magnetic graphene oxide/aptamer separating material]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 87-95页

作者： Xin-Yu Jin Le-Yuan Chen Ya-Nna Liu Wen-Jing Xie Han-Yong Peng State Key Laboratory of environmental Chemistry and ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China. University of Chinese Academy of sciences Beijing 100049 China. School of Environment Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences Hangzhou 310024 China.

17-Estradiol (E2) is a natural steroidal estrogen essential for a variety of physiological functions in organisms. However, external E2, which is renowned for its potent biological effects, is also considered to be an endocrine-disrupting compound (EDC) capable of disturbing the normal operation of the endocrine system, even at nanogram-per-liter (ng/L) concentrations. Studies have revealed that medical and livestock wastewater can be contaminated with E2, which poses potential risks to human health. Currently, the primary method for detecting E2 relies on liquid chromatography-mass spectrometry, which is limited with regard to on-site or large-scale sample testing due to instrumental constraints. Herein, we developed a magnetic graphene oxide (MGO)/aptamer separating material. The MGO was synthesized by creating a water-in-oil microemulsion at 90 ℃, an agarose hydrogel to load the FeO nanoparticles, and layered graphene oxide (GO). In contrast to conventional methods, such as chemical co-precipitation and solvothermal approaches, this method is more time-efficient and does not require high temperature or pressure. Moreover, the use of a physical encapsulation technique for enwrapping the FeO nanoparticles and layered GO eliminates the need for chemical modification. This approach reduces the use of harmful chemicals, ensures complete loading, and results in highly efficient encapsulation. The MGO was characterized using Fourier-transform infrared (FT-IR) spectroscopy and transmission electron microscopy (TEM), as well as dynamic light scattering (DLS) and Zeta potential analyses, which revealed that the FeO nanoparticles had been successfully loaded onto the GO to produce MGO particles mainly around 5 μm in size. Additionally, this study demonstrated that the aqueous MGO dispersion is highly stable. This substance was used to develop a fluorescent biosensor that uses a "turn-on" mechanism to rapidly and highly sensitively detect E2. MGO is capable of adsorbing a fl

关键词： 17-estradiol (E2) fluorescence biosensor magnetic graphene oxide (MGO) magnetic solid phase separation

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Characterization and reactivity of biogenic manganese oxides for ciprofloxacin oxidation

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Journal of environmental sciences 2014年第5期26卷 1154-1161页

作者： Jinjun Tu Zhendong Yang Chun Hu Jiuhui Qu State Key Laboratory of environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesResearch Center for Eco-Environmental Sciences

Biogenic manganese oxides （BioMnOx） were synthesized by the oxidation of Mn（II） with Mn- oxidizing bacteria Pseudomonas sp. G7 under different initial pH values and Mn（II） dosages, and were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and UV-Vis absorption spectroscopy. The crystal structure and Mn oxidation states of BioMnOx depended on the initial pH and Mn（lI） dosages of the medium. The superoxide radical （O2） was observed in Mn-containing （III/IV） BioMnOx suspensions by electron spin resonance measurements. BioMnOx（0.4）-7, with mixed valence of Mn（II/III/IV） and the strongest O^- signals, was prepared in the initial pH 7 and Mn（II） dosage of 0.4 mmol/L condition, and exhibited the highest activity for ciproftoxacin degradation and no Mn（II） release. During the degradation of ciprofloxacin, the oxidation of the Mn（II） formed came from biotic and abiotic reactions in BioMnOx suspensions on the basis of the Mn（II） release and O2- formation from different BioMnOx. The degradation process of ciprofloxacin was shown to involve the cleavage of the hexatomic ring having a secondary amine and carbon-carbon double bond connected to a carboxyl group, producing several compounds containing amine groups as well as small organic acids.

关键词： Mn oxidation state Mn-oxidizing bacteria superoxide radicals ciprofloxacin degradation

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THE FUZZY CORE OF SUM-COMPOUND FUZZY GAMES

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中国科学院研究生院学报 1989年第2期6卷 18-20页

作者： Zhao Jingzhu research center for eco-environmental sciences Academia Sinica

In this paper, the model of sum-compound fuzzy game is established, and the fuzzy core of sum-compound fuzzy game is studied.

关键词： FUZZY games 云西 nonnegative nonempty write strategic

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An equivariant index theorem on R~n in the context of continuous fields of C*-algebras

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Science China Mathematics 2025年

作者： Baiying Ren Hang Wang Zijing Wang research center for Operator Algebras School of Mathematical SciencesEast China Normal University

We prove an equivariant index theorem on the Euclidean space using a continuous field of C*-algebras. This generalizes the work of Elliott et al.（1996）, which is a special case of the algebraic index theorem by Nest and Tsygan （1995）. Using our formula, we see that the equivariant index of the Bott-Dirac operator on R2ncan be explicitly calculated.

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Small molecule inhibitor DDQ-treated hippocampal neuronal cells show improved neurite outgrowth and synaptic branching

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Neural Regeneration research 2025年第9期20卷 2624-2632页

作者： Jangampalli Adi Pradeepkiran Priyanka Rawat Arubala P.Reddy Erika Orlov PHemachandra Reddy Department of Internal Medicine Texas Tech University Health Sciences CenterLubbockTXUSA Department of Nutritional sciences College of Human SciencesTexas Tech UniversityLubbockTXUSA Department of Pharmacology&Neuroscience Texas Tech University Health Sciences CenterLubbockTXUSA Department of Neurology Texas Tech University Health Sciences CenterLubbockTXUSA Department of Speech Language and Hearing SciencesTexas Tech University Health Sciences CenterLubbockTXUSA Department of Public Health Texas Tech University Health Sciences CenterLubbockTXUSA

The process of neurite outgrowth and branching is a crucial aspect of neuronal development and *** and dendrites,sometimes referred to as neurites,are extensions of a neuron's cellular body that are used to start *** we explored the effects of diethyl(3,4-dihydroxyphenethylamino)(quinolin-4-yl)methylphosphonate(DDQ)on neurite developmental features in HT22 neuronal *** this work,we examined the protective effects of DDQ on neuronal processes and synaptic outgrowth in differentiated HT22cells expressing mutant Tau(mTau)*** investigate DDQ chara cteristics,cell viability,biochemical,molecular,western blotting,and immunocytochemistry were *** outgrowth is evaluated through the segmentation and measurement of neural *** neural processes can be seen and measured with a fluorescence microscope by manually tracing and measuring the length of the neurite *** neuronal processes can be observed and quantified with a fluorescent microscope by manually tracing and measuring the length of the neuronal ***-treated mTau-HT22 cells(HT22 cells transfected with cDNA mutant Tau)were seen to display increased levels of synaptophysin,MAP-2,andβ-***,we confirmed and noted reduced levels of both total and p-Tau,as well as elevated levels of microtubule-associated protein 2,β-tubulin,synaptophysin,vesicular acetylcholine transporter,and the mitochondrial biogenesis protein-pe roxisome prolife rator-activated receptor-gamma coactivator-1α.In mTa u-expressed HT22 neurons,we observed DDQ enhanced the neurite characteristics and improved neurite development through increased synaptic *** findings conclude that mTa u-HT22(Alzheimer's disease)cells treated with DDQ have functional neurite developmental chara *** key finding is that,in mTa u-HT22 cells,DDQ preserves neuronal structure and may even enhance nerve development function with mTa u inhibition.

关键词： diethyl(3 4-dihydroxyphenethylamino)(quinolin-4-yl)methylphosphonate(DDQ) hippocampal neuronal cells HT22 neurite outgrowth neuronal development small molecule

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Temporal variation of microbial population in a thermophilic biofilter for SO_2 removal

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Journal of environmental sciences 2016年第1期28卷 4-12页

作者： Jingying Zhang Lin Li Junxin Liu research center for eco-environmental sciences Chinese Academy of Sciences

The performance of a biofilter relies on the activity of microorganisms during the gas contaminant treatment process. In this study, SO2 was treated using a laboratory-scale biofilter packed with polyurethane foam cubes（PUFC）, on which thermophilic desulfurization bacteria were attached. The thermophilic biofilter effectively reduced SO2 within 10 months of operation time, with a maximum elimination capacity of 48.29 g/m^3/*** shifts in the microbial population in the thermophilic biofilter were determined through polymerase chain reaction-denaturing gradient gel electrophoresis and deoxyribonucleic acid（DNA） sequence analysis. The substrate species and environmental conditions in the biofilter influenced the microbial population. Oxygen distribution in the PUFC was analyzed using a microelectrode. When the water-containing rate in PUFC was over 98%, the oxygen distribution presented aerobic–anoxic–aerobic states along the test route on the PUFC. The appearance of sulfate-reducing bacteria was caused by the anaerobic conditions and sulfate formation after 4 months of operation.

关键词： Thermophilic biofilter Sulfur dioxide Microbial population DGGE analysis O2 distribution

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Flow field and dissolved oxygen distributions in the outer channel of the Orbal oxidation ditch by monitor and CFD simulation

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Journal of environmental sciences 2013年第4期25卷 645-651页

作者： Xuesong Guo Xin Zhou Qiuwen Chen Junxin Liu research center for eco-environmental sciences Chinese Academy of Sciences

In the Orbal oxidation ditch, denitrification is primarily accomplished in the outer channel. However, the detailed characteristics of the flow field and dissolved oxygen （DO） distribution in the outer channel are not well understood. Therefore, in this study, the flow velocity and DO concentration in the outer channel of an Orbal oxidation ditch system in a wastewater treatment plant in Beijing （China） were monitored under actual operation conditions. The flow field and DO concentration distributions were analyzed by computed fluid dynamic modeling. In situ monitoring and modeling both showed that the flow velocity was heterogeneous in the outer channel. As a result, the DO was also heterogeneously distributed in the outer channel, with concentration gradients occurring along the flow direction as well as in the cross-section. This heterogeneous DO distribution created many anoxic and aerobic zones, which may have facilitated simultaneous nitrificafion-denitrification in the channel. These findings may provide supporting information for rational optimization of the performance of the Orbal oxidation ditch.

关键词： computed fluid dynamic dissolved oxygen distribution flow field Orbal oxidation ditch

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