Knockdown of the M2 Isoform of Pyruvate Kinase (PKM2) with shRNA Enhances the Effect of Docetaxel in Human NSCLC Cell Lines In Vitro

Tiankui Qiao,Tiankui Qiao,Xibing Zhuang,Wei Chen,Na Xing,Qi Zhang 연세대학교의과대학 2016 Yonsei medical journal Vol.57 No.6

Purpose: The aim of our study was to explore the relationships between the M2 isoform of pyruvate kinase (PKM2) and the sensitivityof human non-small cell lung cancer (NSCLC) cells to docetaxel in vitro. Materials and Methods: With the method of plasmid transfection, we silenced the expression of PKM2 successfully in A549 and H460 cells. Western blotting and real-time PCR were applied to detect PKM2 expression at protein and gene levels. Cell viability was examined by CCK8 assay. Cell cycle distribution and apoptosis were examined by flow cytometry. P21 and Bax were detected. Results: Expression of PKM2 mRNA and protein were significantly decreased by shRNA targeting PKM2. Silencing of PKM2 increaseddocetaxel sensitivity of human NSCLC A549 and H460 cells in a collaborative manner, resulting in strong suppression of cell viability. The results of flow cytometric assays suggested that knockdown of PKM2 or docetaxel treatment, whether used singlyor in combination, blocked the cells in the G2/M phase, which is in consistent with the effect of the two on the expression of p21. Cells with PKM2 silencing were more likely to be induced into apoptosis by docetaxel although knockdown of PKM2 alone can’t induce apoptosis significantly, which is in consistent with the effect of the two on Bax expression. Conclusion: The results suggest that PKM2 knockdown could serve as a chemosensitizer to docetaxel in non-small lung cancer cells through targeting PKM2, leading to inhibition of cell viability, increase of cell arrest of G2/M phase and apoptosis.

D-RADA16-RGD-Reinforced Nano-Hydroxyapatite/Polyamide 66 Ternary Biomaterial for Bone Formation

Bo Qiao,Bin He,Ao Zhou,Yuling Li,Xiaojun Chen,Qiming Yang,Beike Chen,Bo Qiao,Dianming Jiang 한국조직공학과 재생의학회 2019 조직공학과 재생의학 Vol.16 No.2

BACKGROUND: Nano-hydroxyapatite/polyamide 66 (nHA/PA66) is a composite used widely in the repair of bone defects. However, this material is insufficient bioactivity. In contrast, D-RADA16-RGD self-assembling peptide (DRADA16- RGD sequence containing all D-amino acids is Ac-RADARADARADARADARGDS-CONH2) shows admirable bioactivity for both cell culture and bone regeneration. Here, we describe the fabrication of a favorable biomaterial material (nHA/PA66/D-RADA16-RGD). METHODS: Proteinase K and circular dichroism spectroscopy were employed to test the stability and secondary structural properties of peptide D-RADA16-RGD respectively. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the surface of these materials. Confocal laser scanning (CLS), cell counting kit-8 tests (CCK-8), alizarin red S staining, cell immunofluorescence analysis and Western blotting were involved in vitro. Also biosafety and bioactivity of them have been evaluated in vivo. RESULTS: Proteinase K and circular dichroism spectroscopy demonstrated that D-RADA16-RGD in nHA/PA66 was able to form stable-sheet secondary structure. SEM and TEM showed that the D-RADA16-RGD material was 7–33 nm in width and 130–600 nm in length, and the interwoven pore size ranged from 40 to 200 nm. CLS suggests that cells in nHA/PA66/ D-RADA16-RGD group were linked to adjacent cells with more actin filaments. CCK-8 analysis showed that nHA/PA66/ D-RADA16-RGD revealed good biocompatibility. The results of Alizarin-red S staining and Western blotting as well as vivo osteogenesis suggest nHA/PA66/D-RADA16-RGD exhibits better bioactivity. CONCLUSION: This study demonstrates that our nHA/PA66/D-RADA16-RGD composite exhibits reasonable mechanical properties, biocompatibility and bioactivity with promotion of bone formation.

Examining Stock Volatility in the Segmented Chinese Stock Markets: A SWARCH Approach

ZHUO QIAO,WEIWEI QIAO,Wing-Keung Wong 연세대학교 동서문제연구원 2010 Global economic review Vol.39 No.3

This study adopts the SWARCH model to examine the volatile behavior and volatility linkages among the four major segmented Chinese stock indices.We find strong evidence of a regime shift in the volatility of the four markets, and the SWARCH model appears to outperform standard generalized autoregressive conditional heteroskedasticity (GARCH) family models. The evidence suggests that, compared with the A-share markets, B-share markets stay in a high-volatility state longer and are more volatile and shift more frequently between high- and low-volatility states. In addition, the relative magnitude of the high-volatility compared with that of the low-volatility state in the B-share markets is much greater than the case in the two A-share markets. B-share markets are found to be more sensitive to international shocks, while A-share markets seem immune to international spillovers of volatility. Finally, analyses of the volatility spillover effect among the four stock markets indicate that the A-share markets play a dominant role in volatility in Chinese stock markets.

Examining the Day-of-the-Week Effects in Chinese Stock Markets: New Evidence from a Stochastic Dominance Approach

ZHUO QIAO,WEIWEI QIAO,Wing-Keung Wong 연세대학교 동서문제연구원 2011 Global economic review Vol.40 No.3

Many researchers have investigated the existence of day-of-the-week effects in different financial markets. However, they have usually adopted a parametric approach, which is known to have a few limitations. This paper adopts a non-parametric stochastic dominance (SD) approach to examine the day-of-the-week effects in Chinese stock markets. In contrast to the extensive evidence of day-of-the-week effects disclosed by a parametric mean-variance (MV) approach, our SD tests show that the day-of-the-week effect is much weaker. We find that there are only Wednesday effects in Chinese A-share and B-share stock markets.

Ceratovacuna atrovirensa Qiao, a new species from China (Aphididae: Hormaphdinae)

Jiang Li-Yun,Chen Jing,Xu Ying,Qiao Ge-xia 한국응용곤충학회 2021 Journal of Asia-Pacific Entomology Vol.24 No.3

Ceratovacuna atrovirensa Qiao sp.n., a woolly aphid on Indocalamus tessellatus from China, is described and illustrated. The new species is supported by both morphological and molecular data. An updated key to apterous viviparous females of Ceratovacuna is provided. The type specimens are deposited in the National Zoological Museum of China, Institute of Zoology, the Chinese Academy of Sciences, Beijing, China and the Natural History Museum, London, United Kingdom.

Lamb wave-based damage imaging method for damage detection of rectangular composite plates

Qiao, Pizhong,Fan, Wei Techno-Press 2014 Structural monitoring and maintenance Vol.1 No.4

A relatively low frequency Lamb wave-based damage identification method called damage imaging method for rectangular composite plate is presented. A damage index (DI) is generated from the delay matrix of the Lamb wave response signals, and it is used to indicate the location and approximate area of the damage. The viability of this method is demonstrated by analyzing the numerical and experimental Lamb wave response signals from rectangular composite plates. The technique only requires the response signals from the plate after damage, and it is capable of performing near real time damage identification. This study sheds some light on the application of Lamb wave-based damage detection algorithm for plate-type structures by using the relatively low frequency (e.g., in the neighborhood of 100 kHz, more suitable for the best capability of the existing fiber optic sensor interrogator system with the sampling frequency of 500 kHz) Lamb wave response and a reference-free damage detection technique.

Exogenous Spermidine Promoted Ca2+ Absorption in Lettuce Roots and Reduced the Incidence of Tipburn

Qiao Yang,Na Lu,Lei Wang,Xiao-qing Huang,Da-quan Yang,Jin Sun 한국원예학회 2018 원예과학기술지 Vol.36 No.5

A physiological disorder, called tipburn, commonly occurs in lettuce (Lactuca sativa L.), particularly in greenhouse cultivation and in hot seasons, and reduces its marketability. Calcium (Ca) deficiency is the main cause of tipburn injury. In the present study, we investigated the effect of exogenous spermidine (Spd) on the occurrence of tipburn in hydroponically cultivated head lettuce (var. capitata L.) and elucidated the role of Ca ions (Ca2+) in its prevention with respect to absorption and transport. Ca deficiency in the nutrient solution resulted in reduced uptake of Ca2+ in lettuce roots, thereby resulting in Ca deficiency in leaves, leading to leaf senescence and tipburn. An application of exogenous Spd promoted Ca2+ uptake in lettuce roots under Ca deficiency and promoted Ca2+ transportation to leaves, especially to inner leaves, thus delaying leaf senescence and reducing the incidence of tipburn. The results indicated that application of exogenous Spd is an effective method to decrease tipburn in lettuce caused by Ca deficiency.

Integrity

Qiao Luo 한국콘텐츠학회 2018 ICCC International Digital Design Invitation Exhib Vol.2018 No.12

Pollution in the Sea

Qiao Luo 한국콘텐츠학회 2017 ICCC International Digital Design Invitation Exhib Vol.2017 No.5

Integrity

Qiao Luo 한국콘텐츠학회 2018 한국콘텐츠학회 ICCC 논문집 Vol.2018 No.12