Microstructure and Mechanical Properties of Cold Drawn Ti–Nb–Ta–Zr–O Wires for Orthodontic Applications

Wei‑dong Zhang,Junye Ren,Bin Liu,Yong Liu,Zhenggang Wu,Jingwen Qiu 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.7

Ti–36Nb–2Ta–3Zr–0.35O (TNTZO) alloy is an excellent candidate for biomedical applications. In this study, a new methodcombining cold-swaging and cold-drawing was used to fabricate the TNTZO alloy wires with 0.3 mm diameter for orthodonticapplications. The microstructure and mechanical properties of cold-drawn and annealed TNTZO wires (referred toas TNTZO0.3and TNTZO0.3(HT), respectively) were investigated. The results show that the microstructure of cold drawnTNTZO0.3consists of main-sized elongated grains with 70 nm width. After annealing at 700 °C for 5 min, the microstructureof TNTZO0.3(HT) wires becomes equiaxial with a grain size of ~ 5 μm. The cold drawn TNTZO0.3wires exhibit improvedmechanical properties, higher tensile strength (about 1000 MPa) and similar elastic modulus (69 GPa), compared to annealedTNTZO0.3(HT) wires. Besides, TNTZO0.3has higher creep resistance and lower stress exponent (around 2), compared to Tiwires and TC4 wires with the same diameter. These results prove that TNTZO0.3wires have most of the ideal characteristicsof orthodontic wires.

Identification of candidate odorant‐degrading enzyme genes in the antennal transcriptome of Aphidius gifuensis

Kang Zhi‐Wei,Liu Fang‐Hua,Xu Yong‐Yu,Cheng Jia‐Hui,Lin Xiao‐Li,Jing Xiang‐Feng,Tian Hong‐Gang,Liu Tong‐Xian 한국곤충학회 2021 Entomological Research Vol.51 No.1

Odorant‐degrading enzymes (ODEs) have been found in insect antennae and play a critical role in signal chemical degradation once the message is conveyed. Significant progress has been made in characterizing ODEs in a variety of pests but very little is known in their natural enemies. We have carried out an antennae‐ and sex‐specific transcriptome of Aphidius gifuensis, a natural enemy of aphid, to identify the candidate ODEs. Based on the antennae‐ and sex‐specific transcriptome, a total of 100 putative ODEs were identified including one aldehyde oxidase (AOX), four alcohol dehydrogenases (ADs), eight UDP‐glucuronosyltransferases (UGTs), 45 cytochrome P450 (P450s), nine glutathione S‐transferases (GSTs) and 40 carboxylesterases (CCEs or CXEs). Additionally, we used RT‐qPCR to determine the expression profiles of these genes in tissues of both sexes. Based on the phylogenic analysis and tissue‐expression patterns, AgifEstE4, AgifCXE3, AgifCCE4, AgifCCE7, and AgifCCE18 were suggested as key ODEs in A. gifuensis. In addition, the female or male specifically enriched genes, such as AgifCCE17, AgifEstB1, AgifCYP18a1, AgifUGT2C2, were also considered to involve in the chemosensory processing in A. gifuensis. This study not only identified the candidate ODEs in A. gifuensis but also provided source for further exploration of the molecular mechanisms of chemical signal transductions in A. gifuensis, as well as other hymenopteran species.

W(110) 표면에 CO의 흡착

이경희,유위량,한현석,부진효,이순보,곽현태 성균관대학교 기초과학연구소 1998 論文集 Vol.49 No.-

The interaction of CO with W(110) surface was investigated through LEED, TDS, and photoelectron spectroscopy using synchrotron radiation under UHV condition. After CO saturation at RT, two desorption states, called α and β , were observed at about 400 and 1150 K in thermal desorption spectra, respectively. The kinetics of 3-CO followed the first order kinetics, indicating the existence of molecular CO on W(110) surface. This is contrary to the previous results. The O 1s BE(binding energy) of CO adsorbed on W(110) surface at room temperature was 529.9 eV. On the other hand, the O 1s BE of β-CO after heating to 900 K was different from that of oxygen adsorbed W(110) surface, suggesting a different adsorption state. According to the UP valence band spectra, we observed two peaks at near -10.7 eV (4σ) and -7.0 eV (5σ+1π), indicating the molecular adsorption of CO at room temperature. Furthermore we could see the 4σ peak at the various photon energy and elevated temperatures. Comparing the energy separation, Δ(4σ-1π) , between 4σ and 1π UP peaks of chemisorbed CO, we found that an increased separation reflects an decreased C-O bond strength. Therefore on the basis of TDS and photoelectron spectroscopy, we could suggest that β state of CO on W(110) may not be dissociated and has an adsorption geometry of lying-down mode.

Review of the Macrophya formosana group (Hymenoptera: Tenthredinidae) with descriptions of two new species

Meng-Meng LIU,Ze-Jian LI,Mei-Cai WEI 한국곤충학회 2019 Entomological Research Vol.49 No.5

The Macrophya formosana group is reviewed and six species are recognized from Europe and East Asia, among them two new species, M. brevispuralis Li, Liu & Wei sp. nov. and M. pseudoformosana Li, Liu &Wei sp. nov. from China, and four known species, M. crassula (Klug 1817), M. dolichogaster Wei & Ma, 1997, M. formosana Rohwer 1916 and M. liukiuana Takeuchi 1926. A key to all known species of the Macrophya formosana group is provided.

Silencing of Lysyl Oxidase Gene Expression by RNA Interference Suppresses Metastasis of Breast Cancer

Liu, Jian-Lun,Wei, Wei,Tang, Wei,Jiang, Yi,Yang, Hua-Wei,Li, Jing-Tao,Zhou, Xiao Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.7

Objective: The aim of this study was to investigate possible mechanisms of LOX gene effects on invasion and metastasis of breast cancer cells by RNA interference. Methods: LOX-RNAi-LV was designed, synthesized, and then transfected into a breast cancer cell line (MDA-MB-231). Expression of LOX, MMP-2 and MMP-9 was determined by real-time PCR, and protein expression of LOX by Western blotting. Cell migration and invasiveness were assessed with Transwell chambers. A total of 111 cases of breast cancer tissues, cancer-adjacent normal breast tissues, and 20 cases of benign lesion tissues were assessed by immunohistochemistry. Results: Expression of LOX mRNA and protein was suppressed, and the expression of MMP-2 and MMP-9 was significantly lower in the RNAi group than the control group (P<0.05), after LOX-RNAi-LV was transfection into MDA-MB-231 cells. Migration and invasion abilities were obviously inhibited. The expression of LOX protein in breast cancer, cancer-adjacent normal breast tissues and benign breast tumor were 48.6% (54/111), 26.1% (29/111), 20.0% (4/20), respectively, associations being noted with clinical stage, lymph node metastasis, tumor size and ER, PR, HER2, but not age. LOX protein was positively correlated with MMP-2 and MMP-9. Conclusion: LOX displayed an important role in invasion and metastasis of breast cancer by regulating MMP-2 and MMP-9 expression which probably exerted synergistic effects on the extracellular matrix (ECM).

Synthesis of 2,5-Disubstituted Pyrrolidines from N-Alkenyl and Alkynyl N-Benzoyloxysulfonamides Catalyzed by (CuOTf)₂･C₆H₆

Liu, Wei-Min,Liu, Zhen-Hong,Cheong, Wei-Wen,Priscilla, Lu-Yi Teo,Li, Yongxin,Narasaka, Koichi Korean Chemical Society 2010 Bulletin of the Korean Chemical Society Vol.31 No.3

A new synthetic method of 2,5-disubstituted pyrrolidines is developed by the cyclization of unsaturated N-benzoyloxysulfonamides by $(CuOTf)_2{\cdot}C_6H_6$ in refluxing dichloroethane. Various N-4- and N-5-alkenyl and alkynyl N-benzoyloxysulfonamides are cyclized to give pyrrolidines. The cyclization proceeds via addition of sulfonamidoyl radicals to intramolecular unsaturated bonds or allylic hydrogen abstraction with the radical intermediates.

5-Aza-2'-deoxycytidine Induces Hepatoma Cell Apoptosis via Enhancing Methionine Adenosyltransferase 1A Expression and Inducing S-Adenosylmethionine Production

Liu, Wei-Jun,Ren, Jian-Guo,Li, Ting,Yu, Guo-Zheng,Zhang, Jin,Li, Chang-Sheng,Liu, Zhi-Su,Liu, Quan-Yan Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

In hepatocellular cancer (HCC), lack of response to chemotherapy and radiation treatment can be caused by a loss of epigenetic modifications of cancer cells. Methionine adenosyltransferase 1A is inactivated in HCC and may be stimulated by an epigenetic change involving promoter hypermethylation. Therefore, drugs releasing epigenetic repression have been proposed to reverse this process. We studied the effect of the demethylating reagent 5-aza-2'-deoxycitidine (5-Aza-CdR) on MAT1A gene expression, DNA methylation and S-adenosylmethionine (SAMe) production in the HCC cell line Huh7. We found that MAT1A mRNA and protein expression were activated in Huh7 cells with the treatment of 5-Aza-CdR; the status of promoter hypermethylation was reversed. At the same time, MAT2A mRNA and protein expression was significantly reduced in Huh7 cells treated with 5-Aza-CdR, while SAMe production was significantly induced. However, 5-Aza-CdR showed no effects on MAT2A methylation. Furthermore, 5-Aza-CdR inhibited the growth of Huh7 cells and induced apoptosis and through down-regulation of Bcl-2, up-regulation of Bax and caspase-3. Our observations suggest that 5-Aza-CdR exerts its anti-tumor effects in Huh7 cells through an epigenetic change involving increased expression of the methionine adenosyltransferase 1A gene and induction of S-adenosylmethionine production.

Synthesis of 2,5-Disubstituted Pyrrolidines from N-Alkenyl and Alkynyl N-Benzoyloxysulfonamides Catalyzed by (CuOTf)2・C6H6

Wei-Min Liu,Zhen-Hong Liu,Wei-Wen Cheong,Lu-Yi Teo Priscilla,Yongxin Li,Koichi Narasaka 대한화학회 2010 Bulletin of the Korean Chemical Society Vol.31 No.3

A new synthetic method of 2,5-disubstituted pyrrolidines is developed by the cyclization of unsaturated N-benzoyloxysulfonamides by (CuOTf)2·C6H6 in refluxing dichloroethane. Various N-4- and N-5-alkenyl and alkynyl N-benzoyloxysulfonamides are cyclized to give pyrrolidines. The cyclization proceeds via addition of sulfonamidoyl radicals to intramolecular unsaturated bonds or allylic hydrogen abstraction with the radical intermediates.

ST6Gal-I Predicts Postoperative Clinical Outcome for Patients with Localized Clear-cell Renal Cell Carcinoma

Liu, Hai-Ou,Wu, Qian,Liu, Wei-Si,Liu, Yi-Dong,Fu, Qiang,Zhang, Wei-Juan,Xu, Le,Xu, Jie-Jie Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.23

Hyperactivated ${\alpha}2$-6-sialylation on N-glycans due to overexpression of the Golgi enzyme ${\beta}$-galactoside: ${\alpha}2$-6-sialyltransferase (ST6Gal-I) often correlates with cancer progression, metastasis, and poor prognosis. This study was aimed to determine the association between ST6Gal-I expression and the risk of recurrence and survival of patients with localized clear-cell renal cell carcinoma (ccRCC) following surgery. We retrospectively enrolled 391 patients (265 in training cohort and 126 in validation cohort) with localized ccRCC underwent nephrectomy at a single center. Tissue microarrays were constructed for immunostaining of ST6Gal-I. Prognostic value and clinical outcomes were evaluated. High ST6Gal-I expression was associated with Fuhrman grade (p<0.001 and p=0.016, respectively) and the University of California Los-Angeles Integrated Staging System (UISS) score (p=0.004 and p=0.017, respectively) in both cohorts. Patients with high ST6Gal-I expression had significantly worse overall survival (OS) (p<0.001 and p<0.001, respectively) and recurrence free survival (RFS) (p<0.001 and p=0.002, respectively) than those with low expression in both cohorts. On multivariate analysis, ST6Gal-I expression remained associated with OS and RFS even after adjusting for the UISS score. Stratified analysis suggested that the association is more pronounced among patients with low and intermediate-risk disease defined by the UISS score. High ST6Gal-I expression is a potential independent adverse predictor of survival and recurrence in ccRCC patients, and the prognostic value is most prominent in those with low and intermediate-risk disease defined by the UISS score.

Targeting treatment of bladder cancer using PTK7 aptamer-gemcitabine conjugate

Xiang Wei,Peng Yongbo,Zeng Hongliang,Yu Chunping,Zhang Qun,Liu Biao,Liu Jiahao,Hu Xing,Wei Wensu,Deng Minhua,Wang Ning,Liu Xuewen,Xie Jianfei,Hou Weibin,Tang Jin,Long Zhi,Wang Long,Liu Jianye 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

Gemcitabine (GEM) is one of the first-line chemotherapies for bladder cancer (BC), but the GEMs cannot recognize cancer cells and have a low long-term response rate and high recurrence rate with side effects during the treatment of BC. Targeted transport of GEMs to mediate cytotoxicity to tumor and avoid the systemic side effects remains a challenge in the treatment of BC.Based on a firstly confirmed biomarker in BC-protein tyrosine kinase 7 (PTK7), which is overexpressed on the cell membrane surface in BC cells, a novel targeting system protein tyrosine kinase 7 aptamer-Gemcitabine conjugate (PTK7-GEMs) was designed and synthesized using a specific PTK7 aptamer and GEM through auto-synthesis method to deliver GEM against BC. In addition, the antitumor effects and safety evaluation of PTK7-GEMs was assessed with a series of in vitro and in vivo assays.PTK7-GEMs can specifically bind and enter to BC cells dependent on the expression levels of PTK7 and via the macropinocytosis pathway, which induced cytotoxicity after GEM cleavage from PTK7-GEMs respond to the intracellular phosphatase. Moreover, PTK7-GEMs showed stronger anti-tumor efficacy and excellent biosafety in three types of tumor xenograft mice models.These results demonstrated that PTK7-GEMs is a successful targeted aptamer-drug conjugates strategy (APDCs) to treat BC, which will provide new directions for the precision treatment of BC in the field of biomarker-oriented tumor targeted therapy.