Spatiotemporal expression patterns of thymosin and its immune regulation after bacterial stimulation in American cockroach (Periplaneta americana)

Yang Zhen,Xie Jiqin,Yang Yu,Sun Xiaohong,Jing Jie,Shen Yongmei,Yue Bisong,Zhang Xiuyue 한국곤충학회 2021 Entomological Research Vol.51 No.12

Thymosin is a physiologically active polypeptide hormone which has many functions involved in promoting wound healing, promoting hair growth, and accelerating tissue and organ regeneration. American cockroach (Periplaneta americana) has three subtypes thymosin (THY1, THY2, THY3) which are different splices from the same thymosin gene. Real-time PCR was used to detect and analyze the expression differences of THY1 and THY2 in different stages, sexes, tissues and after stimulation by bacteria. Thymosins were expressed in adult, eclosion, and ootheca, and their expression levels were significantly up-regulated during the eclosion period, showing the thymosin might be involved in the eclosion process. The expression levels of thymosins in females were higher than males, and the differences in eclosion stages were more significant (P < 0.01), indicating that they were closely related to development and female reproduction. The expressions of THY1 and THY2 in hemolymph were significantly higher (P < 0.01) than that in other tissues. The up-regulated expression of thymosin in two immune-related tissues (Hemolymph and adipose) after Escherichia coli stimulation further confirmed its involvement in the immune response. Our research would provide a basis for screening of novel pesticides target genes.

GC–MS analysis of chemical constituents and determination of the total antioxidant capacity of adult powder of Periplaneta americana

Yang Zhen,Xie Jiqin,Huang Feiyun,Yang Yu,Zhang Xiuyue,Yue Bisong 한국곤충학회 2022 Entomological Research Vol.52 No.2

Edible insects are alternative sources of high protein. Southeast Asia, South America, Africa, and Europe have recorded edible insects and, especially in Europe and America, there are factories that produce insects as food. In some areas of China, there has also been the habit of eating insects since ancient times. Periplaneta americana is an insect with the homology of medicine and food. In recent years, its medicinal and nutritional functions have attracted extensive attention and research. Its adult powder has been certified as a health product. It not only contains a variety of proteins but also is rich in fatty acids. The composition and antioxidant function of adult powder extract was analyzed in this study. Using adult P. americana powder as the raw material, it was extracted with n-Hexane, dichloromethane, and ethyl acetate, respectively. Gas chromatography–mass spectrometry (GC–MS) removed a total of 60 compounds, and many active components were extracted from P. americana powder for the first time. The parts and relative content of each extracted sample were obtained, and the total antioxidant capacity (T-AOC) of each extracted piece was determined, among which the antioxidant activity of ethyl acetate was the highest.

Oxidative Stress Mediates Chemical Hypoxia-Induced Injury and Inflammation by Activating NF-κb-COX-2 Pathway in HaCaT Cells

Chuntao Yang,Jianqiang Feng,Hongzhong Ling,Meifen Zhang,Zhanli Yang,Xiuyu Wang,Fanqin Zeng,Chuhuai Wang 한국분자세포생물학회 2011 Molecules and cells Vol.31 No.6

Hypoxia of skin is an important physiopathological process in many diseases, such as pressure ulcer, diabetic ulcer, and varicose ulcer. Although cellular injury and inflammation have been involved in hypoxia-induced dermatic injury, the underlying mechanisms remain largely unknown. This study was conducted to investigate the effects of cobalt chloride (CoCl_2), a hypoxia-mimicking agent, on human skin keratinocytes (HaCaT cells) and to explore the possible molecular mechanisms. Exposure of HaCaT cells to CoCl_2 reduced cell viability and caused overproduction of reactive oxygen species (ROS) and oversecretion of interleukin-6 (IL-6) and interleukin-8 (IL-8). Importantly, CoCl_2 exposure elicited overexpression of cyclooxygenase-2 (COX-2) and phosphorylation of nuclear factor-kappa B (NF-κB) p65 subunit. Inhibition of COX-2 by NS-398, a selective inhibitor of COX-2, significantly repressed the cytotoxicity, as well as secretion of IL-6 and IL-8 induced by CoCl2. Inhibition of NF-κB by PDTC (a selective inhibitor of NF-κB) or genetic silencing of p65 by RNAi (Si-p65), attenuated not only the cytotoxicity and secretion of IL-6 and IL-8, but also overexpression of COX-2 in CoCl2-treated HaCaT cells. Neutralizing anti-IL-6 or anti-IL-8 antibody statistically alleviated CoCl2-induced cytotoxicity in HaCaT cells. N-acetyl-L-cysteine (NAC), a well characterized ROS scavenger, obviously suppressed CoCl_2-induced cytotoxicity in HaCaT cells, as well as secretion of IL-6 and IL-8. Additionally, NAC also repressed overexpression of COX-2 and phosphorylation of NF-κB p65 subunit induced by CoCl_2 in HaCaT cells. In conclusion, our results demonstrated that oxidative stress mediates chemical hypoxia-induced injur and inflammatory response through activation of NF-κB–COX-2 pathway in HaCaT cells.

Deciphering the possible role of H2O2 in methylmercury‑induced neurotoxicity in Xenopus laevis

Xufeng Fu,Xiuyu Yang,Xing Du,Qinghua Cui 대한독성 유전단백체 학회 2020 Molecular & cellular toxicology Vol.16 No.3

Backgrounds Methylmercury (MeHg) is regarded as a developmental neurotoxicant but the detailed mechanism remains not completely clear. Methods The Xenopus laevis embryos were exposed to methylmercury chloride and the expression of neurodevelopment and oxidative stress genes was detected by qRT-PCR or Western blotting. PC12 cells were exposed to various levels of H2O2, and then cell cycle, neurite length, neurodevelopment-related genes, protein expression of apoptosis and autophagy were detected. Results The genes of neurodevelopment and oxidative stress were disrupted by methylmercury chloride and H2O2 were increased interestingly in X. laevis embryos. Then, PC12 cells were exposed to H2O2 and the results showed the cell cycle, neurite length, and neurodevelopment-related genes, the proteins apoptosis and autophagy were changed. Conclusion These results supported the idea that neurodevelopment-related gene expression was regulated by oxidative stress and that apoptosis and autophagy pathways were activated by H2O2 and involved in methylmercury neurotoxicity.

An Accelerated Iterative Hard Thresholding Method for Matrix Completion

Juan Geng,Xingang Yang,Xiuyu Wang,Laisheng Wang 보안공학연구지원센터 2015 International Journal of Signal Processing, Image Vol.8 No.7

The matrix completion problem is to reconstruct an unknown matrix with low-rank or approximately low-rank constraints from its partially known samples. Most methods to solve the rank minimization problem are relaxing it to the nuclear norm regularized least squares problem. Recently, there have been some simple and fast algorithms based on hard thresholding operator. In this paper, we propose an accelerated iterative hard thresholding method for matrix completion (AIHT). Then we report numerical results for solving noiseless and noisy matrix completion problems and image reconstruction. The numerical results suggest that significant improvement can be achieved by our algorithm compared to the other reported methods, especially in terms of CPU time.

Multidrug Resistance Mechanisms of Carbapenem Resistant Klebsiella pneumoniae Strains Isolated in Chongqing, China

Jinrong Yan,Shuli Pu,Xiaojiong Jia,XiuYu Xu,Shuangshuang Yang,Jing Shi,Shan Sun,Liping Zhang 대한진단검사의학회 2017 Annals of Laboratory Medicine Vol.37 No.5

Background: Carbapenem-resistant Klebsiella pneumoniae (CRKP) is considered a serious global threat. However, little is known regarding the multidrug resistance (MDR) mechanisms of CRKP. This study investigated the phenotypes and MDR mechanisms of CRKP and identified their clonal characteristics. Methods: PCR and sequencing were utilized to identify antibiotic resistance determinants. Integron gene cassette arrays were determined by restriction fragment length polymorphism (RFLP) analysis. Multi-locus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE) were used for epidemiological analysis. Plasmids were typed by using a PCR-based replicon typing and analyzed by conjugation and transformation assays. Results: Seventy-eight strains were identified as resistant to at least one carbapenem; these CRKP strains had a high prevalence rate (38.5%, 30/78) of carbapenemase producers. Additionally, most isolates harbored MDR genes, including Extended spectrum β-lactamases (ESBLs), AmpC, and quinolone and aminoglycoside resistance genes. Loss of porin genes was observed, and Class 1 integron was detected in 66.7% of the investigated isolates. PFGE and MLST results excluded the occurrence of clonal dissemination among these isolates. Conclusions: A high prevalence of NDM-1 genes encoding carbapenem resistance determinants was demonstrated among the K. pneumoniae isolates. Importantly, this is the first report of blaNDM-1 carriage in a K. pneumoniae ST1383 clone in China and of a MDR CRKP isolate co-harboring blaNDM-1, blaKPC-2, blaCTX-M, blaSHV, acc(6’)-Ib, rmtB, qnrB, and acc(6’)-Ib-cr.

Studies on Pharmacokinetics of Floxuridine in Patients with Trophoblastic Neoplasms

Peng Wang,Zhu Zhu,Qiang Fu,Xiuyu Yang,Dakui Li 한국임상약학회 2004 학술대회 Vol.2004 No.1