Translocation of residual ethoprophos and tricyclazole from soil to spinach

Yuan Xiu,Lee Junghak,Han Heeju,Ju Boeun,Park Eunyoung,Shin Yongho,Lee Jonghwa,Kim Jeong-Han 한국응용생명화학회 2021 Applied Biological Chemistry (Appl Biol Chem) Vol.64 No.3

The dissipation of ethoprophos and tricyclazole in soil and their translocation tendency to spinach were investigated. Prior to field trials, the analytical method for the determination of these pesticide residues was optimized and validated on soil and spinach. The field trial was conducted under greenhouse conditions for two different pretreatment periods with the pesticides. After treating with pesticides 30 (PBI-30) and 60 days (PBI-60) before seeding, soil samples were collected on different days for the dissipation study of soil. Spinach samples were harvested from the soil, and 50% and 100% mature spinach samples were collected. The initial amounts of ethoprophos residue in the PBI-60 and PBI-30 soils were 0.21 and 2.74 mg/kg, respectively, and these both decreased to less than 0.01 mg/kg on the day of spinach harvest. Similar initial residues of tricyclazole were observed in the PBI-60 (0.87 mg/kg) and PBI-30 soils (0.84 mg/kg), and these decreased to 0.44 and 0.34 mg/kg, respectively. The half-lives of ethoprophos in the soils were calculated as 7.6 and 4.8 days, respectively, while relatively long half-lives of 36.5 and 77.0 days were calculated for tricyclazole. According to the pesticide residue amounts in the spinach, the translocation rate from the soil to the spinach was determined. In the case of ethoprophos, the residual amount was already rapidly degraded in the soil, and the translocation rate could not be confirmed. On the other hand, for tricyclazole, it was confirmed that 1.19 to 1.61% of the residual amount in soil was transferred to spinach. According to these results, safe management guidelines for tricyclazole in soil were suggested considering the maximum residue limit on spinach.

Toxicometabolomics of lindane in adult zebrafish (Danio rerio) using GC‑MS/MS and LC‑Orbitrap‑MS/MS

Yuan Xiu,Lee Junghak,Park Eunyoung,Lee Hwa-Kyung,Kim Jeong-Han 한국응용생명화학회 2021 Applied Biological Chemistry (Appl Biol Chem) Vol.64 No.S

Lindane is a broad-spectrum persistent organochlorine pesticide that has been used to control pests for many years. In this study, its toxic mechanisms in adult zebrafish were investigated using targeted metabolomics with GC-MS/MS and non-targeted metabolomics with LC-Orbitrap-MS/MS. Zebrafish was exposed to lindane in water for 48 h in three groups: control, low exposure (1/10 LC50) and high exposure ( LC50). In the zebrafish exposed to low concentration of lindane, 2.24–3.98 mg/kg of lindane were determined, while 35.67–56.46 mg/kg were observed in the zebrafish exposed to high concentration. A total of 118 metabolites were identified from 394 metabolites on GC-MS/MS and 45 metabolites were selected as biomarkers. A total of 62 metabolites were identified on LC-Orbitrap-MS/MS and 7 metabolites were selected as biomarkers. Three groups were well separated on partial least squares-discriminant analysis (PLS-DA), and a total of 52 metabolites in both the targeted and non-targeted metabolites were selected as biomarkers through VIP and ANOVA tests to construct a heatmap. Five metabolic pathways such as the pentose phosphate pathway (PPP), histidine metabolism, phenylalanine metabolism, alanine/aspartate/glutamate metabolism, and phenylalanine/tyrosine/tryptophan biosynthesis, were observed to show toxicologically significant alterations. Oxidative stress was also confirmed through MDA and ROS assays. Such perturbations of the metabolic pathways of zebrafish caused by the exposure to lindane resulted in significant toxicological effects.

LC-MS/MS를 이용한 농산물 중 유기인계 살충제 다성분동시분석법 확립

원수 ( Xiu Yuan ),김창조 ( Chang Jo Kim ),김민 ( Min Kim ),이래근 ( Raekeun Lee ),신희정 ( Hee Jeong Shin ),김이선 ( Leesun Kim ),손경애 ( Kyeong-ae Son ),경기성 ( Kee Sung Kyung ),노현호 ( Hyun Ho Noh ) 한국환경농학회 2022 한국환경농학회 학술대회집 Vol.2022 No.-

농약허용물질목록관리제도가 도입됨에 따라 신속하고 정밀한 다종농약 동시분석에 대한 요구가 증가하고 있다. 특히 잔류가 길지 않은 유기인계 농약은 전 세계적으로 많은 나라들에서 사용하고 있는데 높은 독성을 가지고 있기 때문에 안전성 평가를 위한 다성분 분석법 확립이 필수적이다. 따라서 이 연구는 QuEChERS 방법과 LC-MS/MS를 기반으로 배추, 사과, 고추, 현미 및 대두에 대한 유기인계 살충제 다성분동시분석법을 확립하기 위하여 수행하였다. 분석기기는 ExionLC^TM with QTRAP 5500 system, AB SCIEX를 사용였으며, scheduled MRM (multiple reaction monitoring) mode로 기기분석법을 확립하였다. 시료 중 잔류농약 전처리 방법을 최적화하기 위해 acetonitrile로 추출한 다음 QuEChERS salts에 따른 분배 효율과 흡착제 조성에 따른 정제 효율을 비교 평가하였다. 결과적으로 EN QuEChERS salts을 첨가하여 분배하고 MgSO₄ 150 mg, PSA 25 mg, C18 25 mg으로 정제하는 방법으로 분석법을 최적화하였다. 최적화된 방법은 정량한계, 직선성, 회수율 및 재현성을 평가하는 방식으로 검증하였다. 정량한계는 대상 농약 모두 PLS 기준인 0.01 mg/kg 이하이었으며, 표준검량선의 상관계수는 모두 r²≥0.990로 직선성은 확보되었다고 판단되었다. 0.02 mg/kg 및 0.1 mg/kg 수준에서 수행한 회수율 시험 결과 72.0-115.3% 범위이었으며, 상대표준편차는 모두 11.3% 미만으로 분석법은 적합하다고 판단되었다.

Inhibition of α-glucosidase by 2-thiobarbituric acid: Molecular dynamics simulation integrating parabolic noncompetitive inhibition kinetics

Qin, Xiu-Yuan,Lee, Jinhyuk,Zheng, Li,Yang, Jun-Mo,Gong, Yan,Park, Yong-Doo Elsevier 2018 Process biochemistry Vol.65 No.-

<P><B>Abstract</B></P> <P>The phenomenon of α-glucosidase inhibition has attracted the attention of researchers due to its association with type 2 diabetes treatment in humans. In this study, we found that 2-thiobarbituric acid (TBA) induces complex inhibition of α-glucosidase using kinetics tests and molecular dynamics (MD) simulations. Computational MD and docking simulations demonstrate that TBA interacts with three residues on active sites of α-glucosidase such as Met69, Arg212, and His348. These biochemical tests indicate that TBA reversibly inhibits α-glucosidase in a parabolic noncompetitive manner (<I>IC</I> <SUB>50</SUB> =17.13±1.14mM; <I>K</I> <SUB>i</SUB> =13.25±0.56mM) and that this inhibition is accompanied by a biphasic kinetic process. The tertiary conformational changes were not synchronized with TBA inhibition but we observed hydrophobic disruption after inactivation at higher concentrations of TBA. Our results provide insight into the functional roles of residues located at the active sites of α-glucosidase, and we suggest that compounds similar to TBA (heterocyclic compounds) targeting the key residues of active sites are potential α-glucosidase inhibitors.</P> <P><B>Highlights</B></P> <P> <UL> <LI> 2-Thiobarbituric acid (TBA) induces complex inhibition of α-glucosidase. </LI> <LI> Computational MD simulations demonstrate that TBA interacts with Met69, Arg212, and His348. </LI> <LI> TBA reversibly inhibits α-glucosidase in a parabolic noncompetitive manner (<I>IC</I> <SUB>50</SUB> =17.13±1.14mM; <I>K</I> <SUB>i</SUB> =13.25±0.56mM). </LI> <LI> The high dose of TBA induces hydrophobic disruption after inactivation. </LI> <LI> Heterocyclic compounds targeting the key residues of active sites are potential α-glucosidase inhibitors. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Expression of the E-cadherin/β-catenin/tcf-4 Pathway in Gastric Diseases with Relation to Helicobacter pylori Infection: Clinical and Pathological Implications

Yu, Xiu-Wen,Xu, Qian,Xu, Ying,Gong, Yue-Hua,Yuan, Yuan Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.1

Objective: To determine the expression of E-cadherin, ${\beta}$-catenin, and transcription factor 4 (TCF4) proteins in gastric diseases with relation to Helicobacter pylori infection. Methods: A total of 309 patients including 60 with superficial gastritis (SG), 57 with atrophic gastritis (AG) and 192 with gastric cancer (GC), were enrolled. The expression of E-cadherin, ${\beta}$-catenin, TCF4 proteins in the gastric mucosa was detected by immunohistochemistry and H. pylori infection by immunohistochemistry and PCR. Results: The expression rates of E-cadherin were significantly higher in SG and AG than in GC (P<0.01), while those of ${\beta}$-catenin in the nucleus were significantly lower in SG and AG than in GC (P<0.05). In GC cases, the expression rates of E-cadherin, ${\beta}$-catenin and TCF4 were significantly higher in the intestinal type than in the diffuse type (P<0.05). In GC patients, the expression rate of E-cadherin was significantly higher in the presence of H. pylori than in the absence of infection (P=0.011). Moreover, the expression level of TCF4 and ${\beta}$-catenin protein was significantly higher in the nucleus and cytoplasm in H. pylori positive than in H. pylori negative GC patients, especially in those with the intestinal type (all P < 0.05). Conclusion: The expression of E-cadherin and ${\beta}$-catenin progressively decreases during the process of GC tumorigenesis, while overexpression of TCF4 occurs. H. pylori infection is associated with a significant increase in the expression of E-cadherin and ${\beta}$-catenin in the cytoplasm and nucleus in GC patients, especially those with the intestinal type.

대도시 대안으로서의 강소도시, AI-유니온 시티

박수원(Piao, Xiu Yuan) 한국도시설계학회 2023 도시설계 : 한국도시설계학회지 Vol.24 No.3

Construction of polysulfone anion exchange hybrid membranes by incorporating carbon quantum dots and facilitated transport mechanisms

Yuan Jin,Xiu Zhang,Tianci Feng,Mei-Sheng Li,Huifang Xiao,Shouyong Zhou,Yijiang Zhao,Jing Zhong,Dawei Yang 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.115 No.-

Low ion conductivity and poor alkali resistance are still the two major obstacles for the applications ofanion exchange membranes (AEMs). In this work, the combined strategies of Carbon quantum dots(CQDs) hybrid and cross-linking modification via side-chains designing were employed to prepareorganic–inorganic hybrid AEMs. Then, the cross-linked quaternized polysulfone (CQPSf-CQDs) hybridAEMs by incorporating carbon quantum dots were successfully fabricated. After hybrid and crosslinking,the mechanical properties of CQPSf-CQDs hybrid AEMs were higher than that of the pristineone, reaching 49.4 MPa for the best one. Meanwhile, the existence of CQDs can expand the hydrophilicarea in the membrane, which is beneficial to the transport of OH. The incorporated CQDs interact weaklywith cationic groups in the side chains through hydrogen bonds. The simulation results further demonstratedthat the introduction of CQDs was beneficial to the construction of hydrophilic and hydrophobicdomains, thereby increasing OH conductivity. In addition, the prepared hybrid membranes own excellentdimensional stabilities and ion transport performances. These preliminary results give us a lot ofhopes for further experiments and optimizations for the hybrid AEMs.

Digital Controller Candidate for Point-of-load Synchronous Buck Converter in Tri-mode Mechanism

Xiu, Li-Mei,Zhang, Wei-Ping,Li, Bo,Liu, Yuan-Sheng The Korean Institute of Power Electronics 2014 JOURNAL OF POWER ELECTRONICS Vol.14 No.4

A digital controller with a low-power approach for point-of-load synchronous buck converters is discussed and compared with its analog counterpart to confirm its feasibility for system integration. The tri-mode digital controller IC in $0.35{\mu}m$ CMOS process is presented to demonstrate solutions that include a PID, quarter PID, and robust RST compensators. These compensators address the steady-state, stand-by, and transient modes according to the system operating point. An idle-tone free condition for ${\Sigma}-{\Delta}$ DPWM reduces the inherent tone noise under DC-excitation. Compared with that of the traditional approach, this condition generates a quasi-pure modulation signal. Experimental results verify the closed-loop performances and confirm the power-saving mechanism of the proposed controller.

Calculation of Life-Time Death Probability due Malignant Tumors Based on a Sampling Survey Area in China

Yuan, Ping,Chen, Tie-Hui,Chen, Zhong-Wu,Lin, Xiu-Quan Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.10

Purpose: To calculate the probability of one person's life-time death caused by a malignant tumor and provide theoretical basis for cancer prevention. Materials and Methods: The probability of one person's death caused by a tumor was calculated by a probability additive formula and based on an abridged life table. All data for age-specific mortality were from the third retrospective investigation of death cause in China. Results: The probability of one person's death caused by malignant tumor was 18.7% calculated by the probability additive formula. On the same way, the life-time death probability caused by lung cancer, gastric cancer, liver cancer, esophageal cancer, colorectal and anal cancer were 4.47%, 3.62%, 3.25%, 2.25%, 1.11%, respectively. Conclusions: Malignant tumor is still the main cause of death in one's life time and the most common causes of cancer death were lung, gastric, liver, esophageal, colorectal and anal cancers. Targeted forms of cancer prevention and treatment strategies should be worked out to improve people's health and prolong life in China. The probability additive formula is a more scientific and objective method to calculate the probability of one person's life-time death than cumulative death probability.

Microporous Zn(II)-MOF for Selective C₂H₂ Adsorption and Anti-cancer Activity on Liver Cancer Combined with LL-37

Xiu-Qin Wei,Shuan-Yuan Yang,Xiao-Xia Li,Mei-Li Xu 한국고분자학회 2021 폴리머 Vol.45 No.6

By employment of a semi-rigid carboxylic acid ligand 5,5" -((5-carboxy-1,3-phenylene)bis(azanediyl))diiso- phthalic acid (H5L) with the -NH- joints, a new porous metal-organic framework (MOF) based on Zn(II) ions as nodes has been generated in success, and its chemical formula is {[Zn₃(μ₃-OH)(L)(H₂O₃)]·3DEF·H₂O}n (1). Owing to its Lewis basic -NH- joints and the π-electron-rich benzene rings on the skeleton, the activated complex 1 offers a favourable pore environment for binding C₂H₂ in preference to CO₂ and CH₄. The inhibitory activity of compound on the liver cancer viability was determined through exploiting the Cell Counting Kit-8 kit. Afterwards, the invasion and migration ability for the liver cancer cells was measured after indicated treatment. Multiple binding interactions are identified by performing the molecular docking simulation, indicating the stabilization effect of the Zn complex towards the target protein, and therefore, the proposed drug molecule exhibits good anticancer activities.