NANOTOXICITY OF MULTIWALL CARBON NANOTUBES TO A549 CELLS IN VITRO

FU-DE WANG,Ying Tang,Yong Ji Yang,CHAN JIN,HUA ZHANG,HAO LIANG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.2

Multiwall carbon nanotubes (MWCNTs) have been widely applied in many ¯elds due to theexcellent physical and chemical properties. As the production and applications of nanotubesexpand, public concern about their potential risks to human health has also raised. Cytotoxicityof MWCNTs was evaluated in this study using a cultured human epithelial cell line A549. Uptakeof MWCNTs by cultured A549 cells was observed by TEM imaging. Dose-dependent decrease ofcell viability showed the cytotoxicity of MWCNTs. Signi¯cant reactive oxygen species (ROS)generation and GSH depletion which reduced the cellular antioxidant level could be the majorfactor of cytotoxicity induced by MWCNTs. MWCNTs seemed to trigger the activation of cellautophagy with the intracellular ATG16L1 level increase as a defense mechanism.

Suppression of the Epidermal Growth Factor-like Domain 7 and Inhibition of Migration and Epithelial-Mesenchymal Transition in Human Pancreatic Cancer PANC-1 Cells

Wang, Yun-Liang,Dong, Feng-Lin,Yang, Jian,Li, Zhi,Zhi, Qiao-Ming,Zhao, Xin,Yang, Yong,Li, De-Chun,Shen, Xiao-Chun,Zhou, Jin Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.9

Background: Epidermal growth factor-like domain multiple 7 (EGFL7), a secreted protein specifically expressed by endothelial cells during embryogenesis, recently was identified as a critical gene in tumor metastasis. Epithelial-mesenchymal transition (EMT) was found to be closely related with tumor progression. Accordingly, it is important to investigate the migration and EMT change after knock-down of EGFL7 gene expression in human pancreatic cancer cells. Materials and Methods: EGFL7 expression was firstly testified in 4 pancreatic cancer cell lines by real-time polymerase chain reaction (Real-time PCR) and western blot, and the highest expression of EGFL7 was found in PANC-1 cell line. Then, PANC-1 cells transfected with small interference RNA (siRNA) of EGFL7 using plasmid vector were named si-PANC-1, while transfected with negative control plasmid vector were called NC-PANC-1. Transwell assay was used to analyze the migration of PANC-1 cells. Real-time PCR and western blotting were used to detect the expression change of EGFL7 gene, EMT markers like E-Cadherin, N-Cadherin, Vimentin, Fibronectin and transcription factors like snail, slug in PANC-1, NCPANC-1, and si-PANC-1 cells, respectively. Results: After successful plasmid transfection, EGFL7 gene were dramatically knock-down by RNA interference in si-PANC-1 group. Meanwhile, migration ability decreased significantly, compared with PANC-1 and NC-PANC-1 group. Meanwhile, the expression of epithelial phenotype marker E-Cadherin increased and that of mesenchymal phenotype markers N-Cadherin, Vimentin, Fibronectin dramatically decreased in si-PANC-1 group, indicating a reversion of EMT. Also, transcription factors snail and slug decreased significantly after RNA interference. Conclusions: Current study suggested that highly-expressed EGFL7 promotes migration of PANC-1 cells and acts through transcription factors snail and slug to induce EMT, and further study is needed to confirm this issue.

Study on the Lethal Reason of Overwintering Weedy Rice Seed in Cold Rice Production Area in China

Ming-gen Wu,Jie Yang,De-liang Yang,Feng Xu,Min-jie Fu 한국잡초학회 2011 한국잡초학회 별책(학술대회 초록집) Vol.31 No.2

The outdoor trails were carried out to investigate overwintering survival rate of different weedy rice seeds in two latitude areas including Longjing city located in Jilin province and Donggang city located in Liaoning province in China, respectively. The survival rates of all weedy rice seeds which were frozen under the condition of saturated soil for 3 months are about 0%. The germination rates of weedy rice seeds overwintering in air-dried soil are more than 50%. The death of overwintering weedy rice seed in the two production areas was positively related to its dormancy characteristic, seed water content and temperature during seed frozen period.

Risk Factors for Pulmonary Cement Embolism (PCE) After Polymethylmethacrylate Augmentation: Analysis of 32 PCE Cases

Huizhi Guo,Huasheng Huang,Yang Shao,Qiuli Qin,De Liang,Shuncong Zhang,Yongchao Tang 대한척추신경외과학회 2021 Neurospine Vol.18 No.4

Objective: Pulmonary cement embolism (PCE) is an underestimated but potentially fatal complication after cement augmentation. Although the treatment and follow-up of PCE have been reported in the literature, the risk factors for PCE are so far less investigated. This study aims to identify the preoperative and intraoperative risk factors for the development of PCE. Methods: A total of 1,373 patients treated with the polymethylmethacrylate (PMMA) augmentation technique were retrospectively included. Patients with PCE were divided into vertebral augmentation group and screw augmentation group. Possible risk factors were collected as follows: age, sex, bone mineral density, body mass index, diagnosis, comorbidity, surgical procedure, type of screw, augmented level, number of augmented vertebrae, fracture severity, presence of intravertebral cleft, cement volume, marked leakage in the paravertebral venous plexus, and periods of surgery. Binary logistic regression analyses were used to analyze independent risk factors for PCE. Results: PCE was identified in 32 patients, with an incidence rate of 2.33% (32 of 1,373). For patients who had undergone vertebral augmentation, marked leakage in the paravertebral venous plexus (odds ratio [OR], 1.2; 95% confidence interval [CI], 0.1–10.3; p=0.000) and previous surgery (OR, 16.1; 95% CI, 4.2–61.0; p=0.007) were independent risk factors for PCE. Regarding patients who had undergone screw augmentation, the marked leakage in the paravertebral venous plexus (OR, 4.2; 95% CI, 0.5–37.3; p=0.004) was the main risk factor. Conclusion: Marked leakage in the paravertebral venous plexus and previous surgery were significant risk factors related to PCE. Paravertebral leakage and operator experience should be concerned when performing PMMA augmentation.

A Novel Intermediate Estimator Based Secure Consensus Control for Multi-agent Systems with Application to Networked Multi-axis Motion Synchronization

Jun-Wei Zhu,Chao-Yang Liang,De-Feng He,Xin Wang 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.4

This paper studies the secure consensus control problem of multi-agent systems under DoS attacks onthe sensor, the actuator, and the communication topology. A resilient intermediate estimator based attack tolerantcontrol strategy is proposed. By fully exploiting the hardware redundancies, both of the estimators and the controlprotocols can be reconstructed online according to different DoS attack scenarios. Finally, the experiment results ofthe networked multi-axis motion control system are given to verify the effectiveness of the proposed method.

MicroRNA Let-7c inhibits Bcl-xl expression and regulates ox-LDL-induced endothelial apoptosis

( Bing Qin ),( Bo Xiao ),( De Sheng Liang ),( Ye Li ),( Ting Jiang ),( Huan Yang ) 생화학분자생물학회(구 한국생화학분자생물학회) 2012 BMB Reports Vol.45 No.8

Endothelial cells (ECs) apoptosis induced by oxidized low-density lipoprotein (ox-LDL) is thought to play a critical role in atherosclerosis. MicroRNAs (miRNAs) are a class of noncoding RNAs that posttranscriptionally regulate the expression of genes involved in diverse cell functions, including differentiation, growth, proliferation, and apoptosis. MiRNA let-7 family is known to be involved in the regulation of cell apoptosis. However, the function of let-7 in ox-LDL induced ECs apoptosis and atherosclerosis is still unknown. Here, we show that let-7c expression was markedly up-regulated in ox-LDL induced apoptotic human umbilical cord vein endothelial cells (HUVECs). Let-7c over-expression enhanced apoptosis in ECs whereas inhibition of let-7c could partly alleviate apoptotic cell death mediated by ox-LDL. Searching for how let-7c affected apoptosis, we discovered that antiapoptotic protein Bcl-xl was a direct target of let-7c in ECs. Our data suggest that let-7c contributes to endothelial apoptosis through suppression of Bcl-xl. [BMB Reports 2012; 45(8): 464-469]

중국 제초제 저항성 논잡초 발생 현황 및 대책

吳明根(Wu Minggen),徐鳳(Feng Xu),楊德亮(De Liang Yang),楊杰(Jie Yang) 韓國雜草學會 2012 Weed&Turfgrass Science Vol.32 No.3

China is one of most important countries for production and consumption of herbicide. Although the chemical weeding technology promoted the development of agricultural modernization in Chinese, it led to the negative effects to agriculture. In particular, the weeds resistant herbicide in paddy field had been serious challenge for safe production of rice. The chemical control technology for weed resistant herbicide with effective, low cost and safety characteristic will be key problem being solved in futhure.

Increased Serotonin Signaling Contributes to the Warburg Effect in Pancreatic Tumor Cells Under Metabolic Stress and Promotes Growth of Pancreatic Tumors in Mice

Jiang, Shu-Heng,Li, Jun,Dong, Fang-Yuan,Yang, Jian-Yu,Liu, De-Jun,Yang, Xiao-Mei,Wang, Ya-Hui,Yang, Min-Wei,Fu, Xue-Liang,Zhang, Xiao-Xin,Li, Qing,Pang, Xiu-Feng,Huo, Yan-Miao,Li, Jiao,Zhang, Jun-Feng Elsevier 2017 Gastroenterology Vol.153 No.1

<P><B>Background & Aims</B></P> <P>Desmoplasia and poor vascularity cause severe metabolic stress in pancreatic ductal adenocarcinomas (PDACs). Serotonin (5-HT) is a neuromodulator with neurotransmitter and neuroendocrine functions that contributes to tumorigenesis. We investigated the role of 5-HT signaling in the growth of pancreatic tumors.</P> <P><B>Methods</B></P> <P>We measured the levels of proteins that regulate 5-HT synthesis, packaging, and degradation in pancreata from Kras<SUP>G12D/+</SUP>/Trp53<SUP>R172H/+</SUP>/Pdx1-Cre (KPC) mice, which develop pancreatic tumors, as well as in PDAC cell lines and a tissue microarray containing 81 human PDAC samples. We also analyzed expression levels of proteins involved in 5-HT synthesis and degradation by immunohistochemical analysis of a tissue microarray containing 311 PDAC specimens, and associated expression levels with patient survival times. 5-HT level in 14 matched PDAC tumor and non-tumor tissues were analyzed by ELISA. PDAC cell lines were incubated with 5-HT and cell survival and apoptosis were measured. We analyzed expression of the 5-HT receptor HTR2B in PDAC cells and effects of receptor agonists and antagonists, as well as HTR2B knockdown with small hairpin RNAs. We determined the effects of 5-HT stimulation on gene expression profiles of BxPC-3 cells. Regulation of glycolysis by 5-HT signaling via HTR2B was assessed by immunofluorescence and immunoprecipitation analyses, as well as by determination of the extracellular acid ratio, glucose consumption, and lactate production. Primary PDACs, with or without exposure to SB204741 (a selective antagonist of HTR2B), were grown as xenograft tumors in mice, and SB204741 was administered to tumor-bearing KPC mice; tumor growth and metabolism were measured by imaging analyses.</P> <P><B>Results</B></P> <P>In immunohistochemical analysis of a tissue microarray of PDAC specimens, increased levels of TPH1 and decreased level of MAOA, which regulate 5-HT synthesis and degradation, correlated with stage and size of PDACs and shorter patient survival time. We found levels of 5-HT to be increased in human PDAC tissues compared with non-tumor pancreatic tissues, and PDAC cell lines compared with non-transformed pancreatic cells. Incubation of PDAC cell lines with 5-HT increased proliferation and prevented apoptosis. Agonists of HTR2B, but not other 5-HT receptors, promoted proliferation and prevented apoptosis of PDAC cells. Knockdown of HTR2B in PDAC cells, or incubation of cells with HTR2B inhibitors, reduced their growth as xenograft tumors in mice. We observed a correlation between 5-HT and glycolytic flux in PDAC cells; levels of metabolic enzymes involved in glycolysis, the phosphate pentose pathway, and hexosamine biosynthesis pathway increased significantly in PDAC cells following 5-HT stimulation. 5-HT stimulation led to formation of the HTR2B–LYN–p85 complex, which increased PI3K–Akt–mTOR signaling and the Warburg effect by increasing protein levels of MYC and HIF1A. Administration of SB204741 to KPC mice slowed growth and metabolism of established pancreatic tumors and prolonged survival of the mice.</P> <P><B>Conclusions</B></P> <P>Human PDACs have increased levels of 5-HT, and PDAC cells increase expression of its receptor, HTR2B. These increases allow for tumor glycolysis under metabolic stress and promote growth of pancreatic tumors and PDAC xenograft tumors in mice.</P>