Migration Effect of Selenium in Soil-Grass System

Hu Hua Feng,Jie Xie Lei,Guo Xiao 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

Suppression of Ku80 Correlates with Radiosensitivity and Telomere Shortening in the U2OS Telomerase-negative Osteosarcoma Cell Line

Hu, Liu,Wu, Qin-Qin,Wang, Wen-Bo,Jiang, Huan-Gang,Yang, Lei,Liu, Yu,Yu, Hai-Jun,Xie, Cong-Hua,Zhou, Yun-Feng,Zhou, Fu-Xiang Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.2

Ku70/80 heterodimer is a central element in the nonhomologous end joining (NHEJ) DNA repair pathway, Ku80 playing a key role in regulating the multiple functions of Ku proteins. It has been found that the Ku80 protein located at telomeres is a major contributor to radiosensitivity in some telomerase positive human cancer cells. However, in ALT human osteosarcoma cells, the precise function in radiosensitivity and telomere maintenance is still unknown. The aim of this study was to investigate the effects of Ku80 depletion in the U2OS ALT cell line cell line. Suppression of Ku80 expression was performed using a vector-based shRNA and stable Ku80 knockdown in cells was verified by Western blotting. U2OS cells treated with shRNA-Ku80 showed lower radiobiological parameters (D0, Dq and SF2) in clonogenic assays. Furthermore, shRNA-Ku80 vector transfected cells displayed shortening of the telomere length and showed less expression of TRF2 protein. These results demonstrated that down-regulation of Ku80 can sensitize ALT cells U2OS to radiation, and this radiosensitization is related to telomere length shortening.

Selective miRNA Expression Profile in Chronic Myeloid Leukemia K562 Cell-derived Exosomes

Feng, Dan-Qin,Huang, Bo,Li, Jing,Liu, Jing,Chen, Xi-Min,Xu, Yan-Mei,Chen, Xin,Zhang, Hai-Bin,Hu, Long-Hua,Wang, Xiao-Zhong Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.12

Background: Chronic myeloid leukemia (CML) is a myeloproliferative disorder of hematopoietic stem cell scarrying the Philadelphia (Ph) chromosome and an oncogenic BCR-ABL1 fusion gene. The tyrosine kinase inhibitor (TKI) of BCR-ABL1 kinase is a treatment of choice for control of CML. Objective: Recent studies have demonstrated that miRNAs within exosomes from cancer cells play crucial roles in initiation and progression. This study was performed to assess miRNAs within exosomes of K562 cells. Methods: miRNA microarray analysis of K562 cells and K562 cell-derived exosomes was conducted with the 6th generation miRCURYTM LNA Array (v.16.0). Gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were also carried out. GO terms and signaling pathways were categorized into 66 classes (including homophilic cell adhesion, negative regulation of apoptotic process, cell adhesion) and 26 signaling pathways (such as Wnt). Results: In exosomes, 49 miRNAs were up regulated as compared to K562 cells, and two of them were further confirmed by quantitative real-time PCR. There are differentially expressed miRNAs between K562 cell derived-exosomes and K562 cells. Conclusion: Selectively expressed miRNAs in exosomes may promote the development of CML via effects on interactions (e.g. adhesion) of CML cells with their microenvironment.

Identification and Characterization of the Antifungal Substances of a Novel Streptomyces cavourensis NA4s

( Hua Qi Pan ),( Su Ya Yu ),( Chun Feng Song ),( Nan Wang ),( Hui Ming Hua ),( Jiang Chun Hu ),( Shu Jin Wang ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.3

A new actinomycete strain NA4 was isolated from a deep-sea sediment collected from the South China Sea and showed promising antifungal activities against soilborne fungal pathogens. It was identified as Streptomyces cavourensis by morphological, physiological, and phylogenetic analyses based on its 16S rRNA gene sequence. The main antifungal components were isolated and identified from the fermentation culture as bafilomycins B1 and C1. These compounds exhibited significant antifungal activities and a broad antifungal spectrum. The results suggest that the Streptomyces cavourensis NA4 and bafilomycins B1 and C1 could be used as potential biocontrol agents for soilborne fungal diseases of plants.

A rapid and sensitive molecularly imprinted electrochemiluminescence sensor for Azithromycin determination in biological samples

Hu, Liqin,Zhou, Tingting,Feng, Jingwen,Jin, Hua,Tao, Yun,Luo, Dan,Mei, Surong,Lee, Yong-Ill Elsevier 2018 Journal of Electroanalytical Chemistry Vol.813 No.-

<P><B>Abstract</B></P> <P>Azithromycin (AZM) is a widely used macrolide antibiotic to treat infections caused by bacteria. Considering the side-effect to human health, a rapid and selective electrochemiluminescence (ECL) sensor was fabricated on the basis of molecularly imprinted polymer (MIP) modified carbon paste electrode as a recognition element. We systematically optimized the factors influencing the processes on the extraction and determination for AZM, including the amount of MIP power and paraffin oil, extraction solution, extraction time and the pH of Ru(bpy)<SUB>3</SUB> <SUP>2+</SUP> solution. Under the optimal condition, the wide linear range was observed from 1.0 × 10<SUP>−10</SUP> to 4.0 × 10<SUP>−7</SUP> mol L<SUP>−1</SUP>, and the limit of detection (LOD) was low as 2.3 × 10<SUP>−11</SUP> mol L<SUP>−1</SUP> (S/N = 3). The spiked recoveries of AZM in urine and blood samples were from 98.4% to 113.5% with RSD changing from 3.7% to 13.2%, respectively. The results of AZM determination by this proposed sensor were in accordance with that of high-performance liquid chromatography–tandem mass spectrometry method. Thus, the developed MIP-based ECL sensor will have a great potential application in rapid and sensitive determination of trace AZM in complex biological samples.</P> <P><B>Highlights</B></P> <P> <UL> <LI> ECL sensor </LI> <LI> MIP modified CP electrode </LI> <LI> Trace AZM determined in biological samples </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Dissolution Kinetics of Thiourea in Triglycol Solution

Li, Hua,Guo, Feng,Hu, Guoqin,Zhao, Lei,Zhang, Yadong Korean Chemical Society 2010 대한화학회지 Vol.54 No.1

이소프로필 멀케푸탄은 중요한 약품 중간체이며 싸이오우레아와 트리글리콜은 이소프로필 멀케푸탄을 합성을 하는데 중요한 화합물이다. 그러므로 트리글리콜 용액에서의 싸이오우레아의 용해는 이소프로필 멀케푸탄의 생산에 중요하다. 트리글리콜용액에서 싸이오우레아의 용해 반응속도론을 조사하고 이소프로필 멀케푸탄을 생산하는 대체 공정을 제시하는것이 본 연구의 목적이다. 트리글리콜용액에서 싸이오우레아의 용해 반응속도론을 조사하기 위하여 용액 농도와 반응 온도를 중점적으로 관찰하였다. 싸이오우레아의 용해속도는 용액농도와 온도가 증가할수록 증가하였다. Isopropyl mercaptan is an important pharmaceutical intermediate and chemical material. And thiourea and triglycol are the main materials for the synthesis of isopropyl mercaptan. Therefore the dissolution of thiourea in triglycol solution is very important for the production of isopropyl mercaptan. The aims of this study are to examine the dissolution kinetics of thiourea in triglycol solution, and to present an alternative process for producing isopropyl mercaptan. In order to investigate the dissolution kinetics of thiourea in triglycol solution, the concentrations of solution and reaction temperature were selected as experimental parameters. It was determined that the dissolution rate of thiourea increased with the increase in solution concentration and temperature. An empirical equation was used in fitting the data. Statistical analysis indicated small errors and the results should be reliable.

Association of TNF-α-308 and -238 Polymorphisms with Risk of Cervical Cancer: A Meta-analysis

Pan, Feng,Tian, Jing,Ji, Chu-Shu,He, Yi-Fu,Han, Xing-Hua,Wang, Yong,Du, Jian-Ping,Jiang, Feng-Shou,Zhang, Ying,Pan, Yue-Yin,Hu, Bing Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.11

Published data on the associations between tumor necrosis factor-alpha (TNF-${\alpha}$) promoter -308G>A and -238G>A polymorphisms and cervical cancer risk are inconclusive. To derive a more precise estimation of the relationship, a meta-analysis was performed. Data were collected from MEDLINE and PubMed databases. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were calculated in a fixed/random effect model. 13 separate studies including 3294 cases and 3468 controls were involved in the meta-analysis. We found no association between TNF-${\alpha}$-308G>A polymorphism and cervical cancer in overall population. In subgroup analysis, significantly elevated risks were found in Caucasian population (A vs. G: OR = 1.43, 95% CI = 1.00-2.03; AA vs. GG: OR = 2.09, 95% CI = 1.34-3.25; Recessive model: OR = 2.09, 95% CI = 1.35-3.25) and African population (GA vs. GG: OR = 1.53, 95% CI = 1.02-2.30). An association of TNF-${\alpha}$-238G>A polymorphism with cervical cancer was found (A vs. G: OR = 0.61, 95% CI = 0.47-0.78; GA vs. GG: OR = 0.59, 95% CI = 0.45-0.77; Dominant model: OR = 0.59, 95% CI = 0.46-0.77). When stratified by ethnicity, similar association was observed in Caucasian population (A vs. G: OR = 0.62, 95% CI = 0.46-0.84; GA vs. GG: OR = 0.59, 95% CI = 0.43-0.82; Dominant model: OR = 0.60, 95% CI = 0.44-0.83). In summary, this meta-analysis suggests that TNF-${\alpha}$-238A allele significantly decreased the cervical cancer risk, and the TNF-${\alpha}$-308G>A polymorphism is associated with the susceptibility to cervical cancer in Caucasian and African population.

SIMULATION AND EXPERIMENTAL STUDY OF A NEW ELECTROMECHANICAL BRAKE WITH AUTOMATIC WEAR ADJUSTMENT FUNCTION

Yun Feng Fu,Xin Hua Hu,Wei Rui Wang,Zheng Ge 한국자동차공학회 2020 International journal of automotive technology Vol.21 No.1

This paper presents a novel electromechanical brake (EMB) with automatic wear adjustment function, which has been ignored in most previous studies. With the aim of investigating the parameter characteristics of the EMB system and analyzing the proposed function, the mathematical models of the DC motor, motor friction, worm drive, ball screw and load are established in MATLAB/Simulink. The differences between the simulation and the experiment under step, triangular wave, square wave and sinusoidal input signals are discussed. The parameter characteristics of clamping force-motor current and clamping force-ball screw displacement are obtained, which also verifies that the established model is correct. The results demonstrate that the automatic wear adjustment function of the new EMB could guarantee that the brake stroke and response time remain consistent across each braking manoeuvre.

Structure and property of a vertical cutting Ca0.4Sr0.6Bi4Ti4O15 ferroelectric ceramic

Su-Hua Fan,Ran Yu,Feng-Qing Zhang,Quan-De Che,Wei Hu 한양대학교 세라믹연구소 2011 Journal of Ceramic Processing Research Vol.12 No.3

Ca0.4Sr0.6Bi4Ti4O15 ceramics with a-axis preferred orientation were prepared by a solid-state reaction method. The cylindrical Ca0.4Sr0.6Bi4Ti4O15 ceramics were cut into two types of plates: one was along the cylinder axis (A), and the other was perpendicular to the direction of the cylinder axis. The effects of sintering temperature on the structure and electrical properties of the Ca0.4Sr0.6Bi4Ti4O15 ceramics were investigated. When the sintering temperature was 1180 oC, sample A gave the highest a-axis (200) orientation with a value of about 27.1%. At this sintering temperature, sample A showed better dielectric properties and ferroelectric properties, the relative dielectric constant (εr), dielectric loss (tan δ), remnant polarization (Pr), and coercive field (Ec) were 217.6, 0.0027, 14.2 μC/cm2 and 49.6 kV/cm, respectively.

Indole-3-propionic acid inhibits gut dysbiosis and endotoxin leakage to attenuate steatohepatitis in rats

Ze-Hua Zhao,Feng-Zhi Xin,Yaqian Xue,Zhimin Hu,Yamei Han,Fengguang Ma,Da Zhou,Xiao-Lin Liu,Aoyuan Cui,Zhengshuai Liu,Yuxiao Liu,Jing Gao,Qin Pan,Yu Li,Jian-Gao Fan 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

Microbial metabolites have emerged as critical components that mediate the metabolic effects of the gut microbiota. Here, we show that indole-3-propionic acid (IPA), a tryptophan metabolite produced by gut bacteria, is a potent anti-non-alcoholic steatohepatitis (NASH) microbial metabolite. Here, we demonstrate that administration of IPA modulates the microbiota composition in the gut and inhibits microbial dysbiosis in rats fed a high-fat diet. IPA induces the expression of tight junction proteins, such as ZO-1 and Occludin, and maintains intestinal epithelium homeostasis, leading to a reduction in plasma endotoxin levels. Interestingly, IPA inhibits NF-κB signaling and reduces the levels of proinflammatory cytokines, such as TNFα, IL-1β, and IL-6, in response to endotoxin in macrophages to repress hepatic inflammation and liver injury. Moreover, IPA is sufficient to inhibit the expression of fibrogenic and collagen genes and attenuate diet-induced NASH phenotypes. The beneficial effects of IPA on the liver are likely mediated through inhibiting the production of endotoxin in the gut. These findings suggest a protective role of IPA in the control of metabolism and uncover the gut microbiome and liver cross-talk in regulating the intestinal microenvironment and liver pathology via a novel dietary nutrient metabolite. IPA may provide a new therapeutic strategy for treating NASH.