Anti-Wear and Friction Properties of Nanoparticles as Additives in the Lithium Grease

Ho Chang,Chou-Wei Lan,Chih-Hao Chen,Mu-Jung Kao,Jia-Bin Guo 한국정밀공학회 2014 International Journal of Precision Engineering and Vol. No.

TiO2/CuO nano-particles were dispersed into lithium grease to improve the lubricating properties of the greases. Then, the processof sliding friction was tested. The friction force of the contact interface between a ball and a flat surface with TiO2/CuO nano-greasewas measured for a ball on a flat sliding wear tester. The worn surface was examined by a surface roughness tester and scanningelectron microscopy (SEM). The tested lithium grease was synthesized with 0.5wt.%, 1.0wt.%, 1.5wt.% and 2.0wt.% TiO2/CuO nanoparticles. Results indicate that the TiO2/CuO nano-particle additives can improve the wear resistance of lithium grease and decreasethe friction coefficient. In addition, the results show that a 1.0 wt% content of TiO2 nano-particles is the most efficient in reducingfriction and wear, and can significantly reduce the friction coefficient of the rubbing interface by about 40%, according to the frictiontests. The wear of the lithium grease with a 2.0wt.% content of CuO nano-particles added can reduce wear about by 60% incomparison with lithium grease. Furthermore, the SEM analysis results demonstrate that the addition of tribo-film forms and TiO2/CuO nano-particles on the worn surface is responsible for the decrease in friction and wear.

Curcumin Analogue A501 induces G2/M Arrest and Apoptosis in Non-small Cell Lung Cancer Cells

Xia, Yi-Qun,Wei, Xiao-Yan,Li, Wu-Lan,Kanchana, Karvannan,Xu, Chao-Chao,Chen, Da-Hui,Chou, Pei-Hong,Jin, Rong,Wu, Jian-Zhang,Liang, Guang Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.16

Curcumin and its analogues have been reported to exert anti-cancer activity against a variety of tumors. Here, we reported A501, a new curcumin analogue. The effect of A501 on cell viability was detected by MTT assay, the result showed that A501 had a better inhibiting effect on the four non-small cell lung cancer (NSCLC) cells than that of curcumin. Moreover, Colony forming experiment showed A501 significant restrained cell proliferation. Flow cytometry displayed A501 can cause G2/M arrest and induce apoptosis. Western blotting showed that A501 decreased the expression of cyclinB1, cdc-2, bcl-2, while increased the expression of p53, cleaved caspase-3 and bax. In conclusion, curcumin analogues A501 played antitumor activity by inhibiting cell proliferation and inducing apoptosis of NSCLC cells. And it was likely to be a promising starting point for the development of curcumin-based anticancer drugs.

Maintenance of pegylated liposomal doxorubicin/carboplatin in patients with advanced ovarian cancer: randomized study of an Asian Gynecologic Oncology Group

Chyong-Huey Lai,Elizabeth Vallikad,Hao Lin,Lan-Yan Yang,Shih-Ming Jung,Hsueh-Erh Liu,Yu-Che Ou,Hung-Hsueh Chou,Cheng-Tao Lin,Huei-Jean Huang,Kuan-Gen Huang,Jiantai Qiu,Yao-Ching Hung,Tzu-I Wu,Wei-Yang 대한부인종양학회 2020 Journal of Gynecologic Oncology Vol.31 No.1

Objectives: An Asian Gynecologic Oncology Group phase III randomized trial was conducted to determine whether maintenance chemotherapy could improve progression-free survival (PFS) in stages III/IV ovarian cancer. Methods: Between 2007 and 2014, 45 newly-diagnosed ovarian cancer patients were enrolled after complete remission and randomized (1:1) to arm A (4-weekly carboplatin area under the curve 4 and pegylated liposomal doxorubicin [PLD] 30 mg/m2, n=24) for 6 cycles or arm B (observation, n=21). The primary end-point was PFS. A post hoc translational study was conducted to deep sequence BRCA/homologous recombination deficiency (HRD) genes, because BRCA/HRD mutations (BRCA/HRDm) are known to be associated with better prognosis. Results: Enrollment was slow, accrual was closed when 7+ years had passed. With a median follow-up of 88.9 months, the median PFS was significantly better in arm A (55.5 months) than arm B (9.2 months) (hazard ratio [HR]=0.40; 95% confidence interval [CI]=0.19–0.87; p=0.020), yet the median overall survival was not significantly different in arm A (not reached) than arm B (95.1 months) (p=0.148). Overall grade 3/4 adverse events were more frequent in arm A than arm B (60.9% vs 0.0%) (p<0.001). Quality of life was generally not significantly different. Distribution of BRCA1/2m or BRCA/HRDm was not significantly biased between the two arms. Wild-type BRCA/non-HRD subgroup seemed to fare better with maintenance therapy (HR=0.35; 95% CI=0.11–1.18; p=0.091). Conclusions: Despite limitations in small sample size, it suggests that maintenance carboplatin-PLD chemotherapy could improve PFS in advanced ovarian cancer.

BRCA1/2 mutation status in patients with metachronous breast and ovarian malignancies: clues towards the implementation of genetic counseling

Angel Chao,Yi-Hao Lin,Lan-Yan Yang,Ren-Chin Wu,Wei-Yang Chang,Pi-Yueh Chang,Shih-Cheng Chang,Chiao-Yun Lin,Huei-Jean Huang,Cheng-Tao Lin,Hung-Hsueh Chou,Kuan-Gen Huang,Wen-Ling Kuo,Ting-Chang Chang,Ch 대한부인종양학회 2020 Journal of Gynecologic Oncology Vol.31 No.3

Objective: The characteristics of patients with metachronous breast and ovarian malignancies and the pathogenic role of BRCA1/2 mutations remain poorly understood. We investigated these issues through a review of hospital records and nationwide Taiwanese registry data, followed by BRCA1/2 mutation analysis in hospital-based cases. Methods: We retrospectively retrieved consecutive clinical records of Taiwanese patients who presented with these malignancies to our hospital between 2001 and 2017. We also collected information from the Data Science Center of the Taiwan Cancer Registry (TCR) between 2007 and 2015. Next-generation sequencing and multiplex ligation-dependent probe amplification were used to identify BRCA1/2 mutations and large genomic rearrangements, respectively. When BRCA1/2 mutations were identified in index cases, pedigrees were reconstructed and genetic testing was offered to family members. Results: A total of 12,769 patients with breast cancer and 1,537 with ovarian cancer were retrieved from our hospital records. Of them, 28 had metachronous breast and ovarian malignancies. We also identified 113 cases from the TCR dataset. Eighteen hospital-based cases underwent BRCA1/2 sequencing and germline pathogenic mutations were detected in 7 patients (38.9%, 5 in BRCA1 and 2 in BRCA2). All BRCA1/2 mutation carriers had ovarian high-grade serous carcinomas. Of the 12 patients who were alive at the time of analysis, 5 were BRCA1/2 mutation carriers. All of them had family members with BRCA1/2-associated malignancies. Conclusions: Our results provide pilot evidence that BRCA1/2 mutations are common in Taiwanese patients with metachronous breast and ovarian malignancies, supporting the clinical utility of genetic counseling.

Synthesis and Effect of Nanogrease on Tribological Properties

Ho Chang,Mu-Jung Kao,Jin-De Luo,Chou-Wei Lan 한국정밀공학회 2015 International Journal of Precision Engineering and Vol. No.

This study aims to improve the lubrication performance of grease by letting Tin (Sn) nanoparticles dispersed in lithium grease, and tests the tribological properties of nanogrease. We use the chemical reduction method to prepare Sn nanoparticles of different particle sizes. After applying Sn nanogrease on the self-made pin-on-disk tribology tester that meets ASTM G99 standards, this study explores the properties of wear resistance and friction decreases of nanogrease with nanparticles of different particle sizes, concentrations and loads. Experimental results show that adding Sn nanoparticles to lithium grease can enhance wear resistance and reduce the coefficient of friction. Under the condition that Sn nanoparticles are in smaller particle size and at a concentration of 1.0 wt.%, friction and wear can both be reduced significantly. Compared to pure lithium base grease, when the grease has loads of 39.2 N and 49 N respectively, the friction coefficients reduce from 0.05434 to 0.01985 and from 0.05635 to 0.02155, with reduction rates at around 63.5% and 61.8%, respectively. Moreover, wear scar diameters decrease from 0.7651 mm to 0.3145 mm and from 0.8263 mm to 0.3658 mm, with reduction rates at around 58.9% and 55.7%, respectively. Additionally, through SEM photographs, this study proves that Sn nanoparticles produce filling and sedimentary effects on wear surfaces.