Effects of Ti nonstoichiometry on microstructure, dielectric, ferroelectric and piezoelectric properties of (Na0.54Bi0.5)0.94Ba0.06Ti1+xO3 lead-free ceramics

Xu-mei Zhao,Xiao-Ming Chen,Jian Wang,Xiao-xia Liang,Jian-Ping Zhou,Peng Liu 한양대학교 세라믹연구소 2015 Journal of Ceramic Processing Research Vol.16 No.1

The lead-free ceramics (Na0.54Bi0.5)0.94Ba0.06Ti1+xO3 with x = −0.02, 0, 0.02, and 0.04 were prepared by a solid-state reaction method. Effects of Ti4+ nonstoichiometry on crystallite structure, microstructure, dielectric, ferroelectric and piezoelectric properties were studied. The ceramics with x = −0.02 and 0 exhibit typical diffraction peaks of perovskite structure. A secondary phase appears in the ceramics with x = 0.02 and 0.04. The rhombohedral-tetragonal morphotropic phase boundary exists in all samples, and the relative amount of the tetragonal phase changes with the increase in the Ti4+ amount from deficiency to excess. Grain sizes and shape of the ceramics are unaffected by changes in Ti4+ nonstoichiometry. But, dielectric, ferroelectric and piezoelectric properties of the ceramics are close related to the Ti4+ amounts. Compared with the ceramic with x = 0, the ceramics with the Ti4+ nonstoichiometry have higher depolarization temperature, lower maximum dielectric constant, decreased piezoelectric constant and ferroelectric properties.

Optimization of Reference Genes for Normalization of the Quantitative Polymerase Chain Reaction in Tissue Samples of Gastric Cancer

Zhao, Lian-Mei,Zheng, Zhao-Xu,Zhao, Xiwa,Shi, Juan,Bi, Jian-Jun,Pei, Wei,Feng, Qiang Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.14

For an exact comparison of mRNA transcription in different samples or tissues with real time quantitative reverse transcription-polymerase chain reaction (qRT-PCR), it is crucial to select a suitable internal reference gene. Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and beta-actin (ACTB) have been frequently considered as house-keeping genes to normalize for changes in specific gene expression. However, it has been reported that these genes are unsuitable references in some cases, because their transcription is significantly variable under particular experimental conditions and among tissues. The present study was aimed to investigate which reference genes are most suitable for the study of gastric cancer tissues using qRT-PCR. 50 pairs of gastric cancer and corresponding peritumoral tissues were obtained from patients with gastric cancer. Absolute qRT-PCR was employed to detect the expression of GAPDH, ACTB, RPII and 18sRNA in the gastric cancer samples. Comparing gastric cancer with corresponding peritumoral tissues, GAPDH, ACTB and RPII were obviously upregulated 6.49, 5.0 and 3.68 fold, respectively. Yet 18sRNA had no obvious expression change in gastric cancer tissues and the corresponding peritumoral tissues. The expression of GAPDH, ${\beta}$-actin, RPII and 18sRNA showed no obvious changes in normal gastric epithelial cells compared with gastric cancer cell lines. The carcinoembryonic antigen (CEA), a widely used clinical tumor marker, was used as a validation gene. Only when 18sRNA was used as the normalizing gene was CEA obviously elevated in gastric cancer tissues compared with peritumoral tissues. Our data show that 18sRNA is stably expressed in gastric cancer samples and corresponding peritumoral tissues. These observations confirm that there is no universal reference gene and underline the importance of specific optimization of potential reference genes for any experimental condition.

G Protein–Coupled Receptor 30 Mediates the Anticancer Effects Induced by Eicosapentaenoic Acid in Ovarian Cancer Cells

Yue Zhao,Meng-Fei Zhao,Mei-Lin Yang,Tian-Yu Wu,Cong-Jian Xu,Jing-Mei Wang,Chao-Jun Li,Xi Li 대한암학회 2020 Cancer Research and Treatment Vol.52 No.3

Purpose: While numerous epidemiological studies have indicated that omega-3 polyunsaturated fatty acids have anticancer properties in various cancers, the effects and mechanisms of eicosapentaenoic acid (EPA) in ovarian cancer cell growth are poorly understood. Materials and Methods: ES2 ovarian clear cell carcinoma cells and SKOV3 adenocarcinoma cells were treated with palmitic acid or EPA, followed by flow cytometry and cell counting to measure apoptosis and proliferation, respectively. A modified protein lipid overlay assay was used to further verify whether EPA was a ligand of G protein–coupled receptor 30 (GPR30) in ES2 cells. The levels of apoptosis-related genes, phosphorylated AKT, and phosphorylated ERK1/2 were detected to explore the underlying mechanism. Finally, inhibitory effect of EPA on tumor growth via GPR30 was determined in vitro and in vivo. Results: EPA suppressed ES2 ovarian clear cell carcinoma cells growth via GPR30, a novel EPA receptor, by inducing apoptosis. As a ligand of GPR30, EPA activated the GPR30-cAMP– protein kinase A signaling pathway. When GPR30 was suppressed by siRNA or its inhibitor G15, the antiproliferative action of EPA was impaired. Furthermore, EPA inhibited tumor growth by blocking the activation of AKT and ERK. In the mouse xenograft model, EPA decreased tumor volume and weight through GPR30 by blocking tumor cell proliferation. Conclusion: These results confirm that EPA is a tumor suppressor in human ovarian clear cell carcinoma cells and functions through a novel fatty acid receptor, GPR30, indicating a mechanistic linkage between omega-3 fatty acids and cancers.

Genetic Variants of NBS1 Predict Clinical Outcome of Platinum-based Chemotherapy in Advanced Non-small Cell Lung Cancer in Chinese

Xu, Jia-Li,Hu, Ling-Min,Huang, Ming-De,Zhao, Wan,Yin, Yong-Mei,Hu, Zhi-Bin,Ma, Hong-Xia,Shen, Hong-Bing,Shu, Yong-Qian Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.3

Objective: NBS1 plays a key role in the repair of DNA double-strand break (DSB). We conducted this study to investigate the effect of two critical polymorphisms (rs1805794 and rs13312840) in NBS1 on treatment response and prognosis of advanced non-small cell lung cancer (NSCLC) patients with platinum-based chemotherapy. Methods: Using TaqMan methods, we genotyped the two polymorphisms in 147 NSCLC patients. Odds ratios (ORs) and their 95% confidential intervals (CIs) were calculated as a measure of difference in the response rate of platinum-based chemotherapy using logistic regression analysis. The Kaplan-Meier and log-rank tests were used to assess the differences in progression-free survival (PFS) and overall survival (OS). Cox proportional hazards model was applied to assess the hazard ratios (HRs) for PFS and OS. Results: Neither of the two polymorphisms was significantly associated with treatment response of platinum-based chemotherapy. However, patients carrying the rs1805794 CC variant genotype had a significantly improved PFS compared to those with GG genotype (16.0 vs. 8.0 months, P = 0.040). Multivariable cox regression analysis further showed that rs1805974 was a significantly favorable prognostic factor for PFS [CC/CG vs. GG: Adjusted HR = 0.62, 95% CI: 0.39-0.99; CC vs. CG/GG: Adjusted HR = 0.56, 95% CI: 0.32-0.97). Similarly, rs13312840 with a small sample size also showed a significant association with PFS (CC vs. CT/TT: Adjusted HR = 25.62, 95% CI: 1.53-428.39). Conclusions: Our findings suggest that NBS1 polymorphisms may be genetic biomarkers for NSCLC prognosis especially PFS with platinum-based chemotherapy in the Chinese population.

Antiproliferative Effects of Celecoxib in Hep-2 Cells through Telomerase Inhibition and Induction of Apoptosis

Zhao, Yong-Qiang,Feng, Hui-Wei,Jia, Tao,Chen, Xue-Mei,Zhang, Hui,Xu, An-Ting,Zhang, Hai-Ling,Fan, Xian-Liang Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.12

Background: To investigate the effect of celecoxib on telomerase activity and apoptosis in a human laryngeal squamous carcinoma cell line (Hep-2 cells). Materials and Methods: The growth inhibition rate of Hep-2 cells in vitro was measured by MTT assay, and apoptosis by TUNEL assay and flow cytometry (FCM). The TRAP-ELISA method was used to determine telomerase activity in Hep-2 cells. The mRNA expression of human telomerase RNA component(hTR), human telomerase reverse transcriptase (hTERT) and human telomerase-associated protein(hTEP1) was determined by RT-PCR assay. Expression of Bax and Bcl-2 proteins was assessed by Western blotting. Results: Celecoxib can inhibit proliferation and induce apoptosis in a dose- and time-dependent manner, repress telomerase activity, decrease hTERT mRNA and Bcl-2 protein expression and increase Bax protein expression, PGE2 had no effect on telomerase. Conclusions: Celecoxib had the antiproliferative and pro-apoptotic effect in Hep-2 cells. Apoptosis was accompanied by a decrease in telomerase activity which was directly correlated with hTERT mRNA and up-regulation of Bax/Bcl-2. Bcl-2 may thus play an important role in telomerase activity as well as apoptosis.

Association between Dietary Behavior and Esophageal Squamous Cell Carcinoma in Yanting

Zhao, Lin,Liu, Chun-Ling,Song, Qing-Kun,Deng, Ying-Mei,Qu, Chen-Xu,Li, Jun Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.20

Background: Yanting is one of high risk areas for esophageal cancer and the screening program was therefore initiated there. This study was aimed to investigate the dietary behaviors on the risk of esophageal squamous cell carcinoma (ESCC), among the individuals with normal and abnormal esophagus mucosa. Materials and Methods: A frequency matched case-controls study was proposed to estimate the different distribution of dietary behavior between individuals of control, esophagitis and cancer groups. Cancer cases were selected from hospitals. Esophagitis cases and controls were selected from screening population for ESCC. Health workers collected data for 1 year prior to interview, in terms of length of finishing a meal, temperature of eaten food and interval between water boiling and drinking. Chi-square, Kruskal-Wallis tests and unconditional logistic regression model were used to estimate differences and associations between groups. Results: Compared with controls, length of finishing a meal ${\geq}15mins$ was related to a reduced OR for cancer (OR=0.46, 95%CI, 0.22-0.97) and even compared with cases of esophagitis, the OR of cancer was reduced to 0.30 (95%CI, 0.13-0.72). The OR for often eating food at a high temperature was 2.48 (95%CI 1.06, 5.82) for ESCC as compared with controls. Interval between water boiling and drinking of ${\geq}10mins$ was associated with lower risk of cancer: the OR was 0.18 compared with controls and 0.49 with esophagitis cases (p<0.05). Conclusions: Length of eating food ${\geq}15mins$ and interval between water boiling and drinking ${\geq}10mins$ are potentially related to reduced risk of esophageal SCC, compared with individuals with normal and abnormal esophageal mucosa. Recommendations to Yanting residents to change their dietary behaviors should be made in order to reduce cancer risk.

Metabolites from the Fungus Cephalosporium sp. AL031

Yun-Mei Bi,Xu-Bin Bi,Fang A,Qian-Rong Zhao 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.3

A new pyrone derivative, 7, 9-dihydroxy-10-methyl-2H, 4aH, 6H, 10bH-pyrano[5,6-c][2]benzopyran- 2,6-dione (1), was isolated from a culture broth of a strain of the fungus Cephalosporium sp. AL031, together with three known compounds, 3-acetyl-7-hydroxy-5-methoxyl-3Hisobenzofuran- 1-one (2), vermopyrone (3), and 5-methylmellein (4). Their structures were elucidated by spectroscopic analysis including MS and 2D-NMR. Compounds 2, 3, and 4 are reported for the first time from fermentation broth of this fungus through the present study.

A Rapidly New-typed Detection of Norovirus Based on F0F1-ATPase Molecular Motor Biosensor

Zhuo Zhao,Jie Zhang,Mei-Ling Xu,Zhi-Peng Liu,Hua Wang,Ming Liu,Yan-Yan Yu,Li Sun,Hui Zhang,Hai-Yan Wu 한국생물공학회 2016 Biotechnology and Bioprocess Engineering Vol.21 No.1

In order to adapt port rapid detection of food borne norovirus, presently we developed a new typed detection method based on F0F1-ATPase molecular motor biosensor. A specific probe was encompassed the conservative region of norovirus and F0F1-ATPase within chromatophore was constructed as a molecular motor biosensor through the “ε-subunit antibody-streptomycinbiotin- probe” system. Norovirus was captured based on probe-RNA specific binding. Our results demonstrated that the Limit of Quantification (LOQ) is 0.005 ng/mL for NV RNA and also demonstrated that this method possesses specificity and none cross-reaction for food borne virus. What’s more, the experiment used this method could be accomplished in 1 h. We detected 10 samples by using this method and the results were consistent with RT-PCR results. Overall, based on F0F1-ATPase molecular motors biosensor system we firstly established a new typed detection method for norovirus detection and demonstrated that this method is sensitive and specific and can be used in the rapid detection for food borne virus.

Metabolites from the Fungus Cephalosporium sp. AL031

Bi, Xu-Bin,A, Fang,Zhao, Qian-Rong,Bi, Yun-Mei 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.3

Promoting effect of Mn and Ti on the structure and performance of Co3O4 catalysts for oxidation of dibromomethane

Jian Mei,Zan Qu,Songjian Zhao,Xiaofang Hu,Haomiao Xu,Naiqiang Yan 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.57 No.-

Co3O4 catalysts modified with Mn and Ti, prepared by co-precipitation method, were used for catalytic oxidation of dibromomethane (CH2Br2), a model molecule for brominated volatile organic compounds (BVOCs). Addition of Ti or Ti + Mn distorted the crystal structure and led to the formation of a Co–O–Ti solid solution. The addition of Mn further enhanced the surface acidity and redox ability of the catalysts. Co–Mn–Ti exhibited the highest activity with a T90 of approximately 234 °C and the highest selectivity to CO2 at low temperatures. Additionally, Co–Mn–Ti showed good stability for at least 30 h at 500 ppm CH2Br2, 0 or 2 vol% H2O, 0 or 500 ppm p-xylene (PX), and 10% O2 at a gas hourly space velocity of 60,000 h−1, and the final products were COx, Br2, and HBr, without the formation of other Br-containing organic byproducts. This high catalytic activity was attributed to its high specific area, high surface acidity, and strong redox property. Furthermore, the synergetic effect of Co, Mn, and Ti made it superior for CH2Br2 oxidation. A plausible reaction mechanism for CH2Br2 oxidation over Co–Mn–Ti catalysts was proposed based on the analysis of the products and in situ diffuse-reflectance infrared Fourier transform spectroscopy results.