Preparation of Silver Nanocap Arrays and Their Surface-enhanced Raman Scattering Activity

Chunxu Wang,Duo Xu,Yuhai Wang,Li Wang,Lei Chen,Xiangxin Xue,Zhengkun Qin 대한화학회 2017 Bulletin of the Korean Chemical Society Vol.38 No.10

In this article, a surface-enhanced Raman scattering (SERS) substrate of silver nanocap arrays was reported. With increasing the size of nanocaps, the localized surface plasmon resonance (LSPR) of the arrays exhibited tunable ability in the visible spectral region. The optical response of the nanocap arrays stimulated their use in SERS experiments. The assessment of SERS activity of the nanocap arrays was performed by using the 514.5 nm excitation line, and different average enhancement factor (EF) values were obtained. The good tunability of LSPR, relatively high average EF values and long-range order of these substrates suggest that the silver nanocap arrays have promising applications as functional components in spectroscopy, immunoassay, biosensors, and biochips.

PRR11 and SKA2 gene pair is overexpressed and regulated by p53 in breast cancer

Wang, Yitao,Zhang, Chunxue,Mai, Li,Niu, Yulong,Wang, Yingxiong,Bu, Youquan Korean Society for Biochemistry and Molecular Biol 2019 BMB Reports Vol.52 No.2

Our previous study found that two novel cancer-related genes, PRR11 and SKA2, constituted a classic gene pair that was regulated by p53 and NF-Y in lung cancer. However, their role and regulatory mechanism in breast cancer remain elusive. In this study, we found that the expression levels of PRR11 and SKA2 were upregulated and have a negative prognotic value in breast cancer. Loss-of-function experiments showed that RNAi-mediated knockdown of PRR11 and/or SKA2 inhibited proliferation, migration, and invasion of breast cancer cells. Mechanistic experiments revealed that knockdown of PRR11 and/or SKA2 caused dysregulation of several downstream genes, including CDK6, TPM3, and USP12, etc. Luciferase reporter assays demonstrated that wild type p53 significantly repressed the PRR11-SKA2 bidirectional promoter activity, but not NF-Y. Interestingly, NF-Y was only essential for and correlated with the expression of PRR11, but not SKA2. Consistently, adriamycin-induced (ADR) activation of endogenous p53 also caused significant repression of the PRR11 and SKA2 gene pair expression. Notably, breast cancer patients with lower expression levels of either PRR11 or SKA2, along with wild type p53, exhibited better disease-free survival compared to others with p53 mutations and/or higher expression levels of either PRR11 or SKA2. Collectively, our study indicates that the PRR11 and SKA2 transcription unit might be an oncogenic contributor and might serve as a novel diagnostic and therapeutic target in breast cancer.

Target-biased informed trees: sampling-based method for optimal motion planning in complex environments

Wang Xianpeng,Ma Xinglu,Li Xiaoxu,Ma Xiaoyu,Li Chunxu 한국CDE학회 2022 Journal of computational design and engineering Vol.9 No.2

Aiming at the problem that the progressively optimized Rapidly-exploring Random Trees Star (RRT*) algorithm generates a large number of redundant nodes, which causes slow convergence and low search efficiency in high-dimensional and complex environments. In this paper we present Target-biased Informed Trees (TBIT*), an improved RRT* path planning algorithm based on target-biased sampling strategy and heuristic optimization strategy. The algorithm adopts a combined target bias strategy in the search phase of finding the initial path to guide the random tree to grow rapidly toward the target direction, thereby reducing the generation of redundant nodes and improving the search efficiency of the algorithm; after the initial path is searched, heuristic sampling is used to optimize the initial path instead of optimizing the random tree, which can benefit from reducing useless calculations, and improve the convergence capability of the algorithm. The experimental results show that the algorithm proposed in this article changes the randomness of the algorithm to a certain extent, and the search efficiency and convergence capability in complex environments have been significantly improved, indicating that the improved algorithm is feasible and efficient.

A Light-Weighted Data Trust Model in WSN

Na Wang,Liping Gao,Chunxue Wu 보안공학연구지원센터(IJGDC) 2014 International Journal of Grid and Distributed Comp Vol.7 No.2

Research in Distributed Evolution based on Real-time Collaboration Technology

Shanshan Wang,Liping Gao,Sizhen Zhu,Chunxue Wu 보안공학연구지원센터 2015 International Journal of Multimedia and Ubiquitous Vol.10 No.3

Evolution design takes the advantage of the evolution technology into the art design, and designers can achieve satisfactory products by performing evolutionary operations. It’s a powerful method in the procedure of the art design. However, the traditional evolution running on single site leads to the low efficiency and the less diversity. In addition, the products just represent the aesthetics of the single site. Based on these problems, this paper aims at using distributed evolution technology to complete the collaborative evolution, broadcasting evolutionary operations among distributed sites and executing evolutionary operations on each site. Then, the acquired products could represent the aesthetics of most sites due to its rich diversity. The paper mainly solves the problems of the operation conflicts which come from different sites, builds a new hybrid document model designs several algorithms based on Operation Transformation (OT) to solve the conflicts, and describes the procedure of the consistency maintenance. The proposed solution has been theoretically verified for its correctness in hybrid model.

MiR-144-3p and Its Target Gene beta-Amyloid Precursor Protein Regulate 1-Methyl-4-Phenyl-1,2-3,6-Tetrahydropyridine-Induced Mitochondrial Dysfunction

Lixuan Wang,Kuo Li,Junling Zhang,Chunxue Ji 한국분자세포생물학회 2016 Molecules and cells Vol.39 No.7

MicroRNAs (miRNAs) have been reported to be involved in many neurodegenerative diseases. The present study focused on the role of hsa-miR-144-3p in one of the neurodegenerative diseases, Parkinson’s disease (PD). Our study showed a remarkable down-regulation of miR-144-3p expression in 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-treated SH-SY5Y cells. MiR-144-3p was then overexpressed and silenced in human SH-SY5Y cells by miRNA-mimics and miRNA-inhibitor transfections, respectively. Furthermore, -amyloid precursor protein (APP) was identified as a target gene of miR-144-3p via a luciferase reporter assay. We found that miR-144-3p overexpression significantly inhibited the protein expression of APP. Since mitochondrial dysfunction has been shown to be one of the major pathological events in PD, we also focused on the role of miR-144-3p and APP in regulating mitochondrial functions. Our study demonstrated that up-regulation of miR-144-3p increased expression of the key genes in-volved in maintaining mitochondrial function, including peroxisome proliferator-activated receptor γ coactivator-1 (PGC-1), nuclear respiratory factor 1 (NRF-1) and mitochondrial transcription factor A (TFAM). Moreover, there was also a significant increase in cellular ATP, cell viability and the relative copy number of mtDNA in the presence of miR-144-3p overexpression. In contrast, miR-144-3p silencing showed opposite effects. We also found that APP overexpression significantly decreased ATP level, cell viability, the relative copy number of mtDNA and the expression of these three genes, which reversed the effects of miR-144-3p overexpression. Taken together, these results show that miR-144-3p plays an important role in maintaining mitochondrial function, and its target gene APP is also involved in this process.

Synthesis of Praseodymium-Doped TiO₂ Nanocatalysts by Sol-Microwave and Their Photocatalytic Activity Study

Huang, Fengping,Wang, Shuai,Zhang, Shuang,Fan, Yingge,Li, Chunxue,Wang, Chuang,Liu, Chun Korean Chemical Society 2014 Bulletin of the Korean Chemical Society Vol.35 No.8

The praseodymium-doped $TiO_2$ photocatalyst samples, which could degrade methyl orange under UV irradiation, were prepared by sol-microwave method for improving the photocatalytic activity of $TiO_2$. The resulting materials were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Raman spectra, Fourier transform infrared spectra (FTIR) and Ultraviolet-visible diffuse reflectance spectra (UV-vis DRS). It was found Pr doping retarded the growth of crystalline size and the phase transformation from anatase to rutile, and narrowed the band gap energy. Praseodymium doping brought about remarkable improvement in the photoactivity. The optimal dopant amount of Pr was 2% by molar of cement and the calcination temperature was $500^{\circ}C$ for the best photocatalytic activity. The improvement of photocatalytic activity was ascribed to the occurrence of lattice distortion and the effective containment of the recombination of the electron-hole by $Pr^{3+}$.

Effect of Hydrogen on O₂ Adsorption and Dissociation on a TiO₂ Anatase (001) Surface

Liu, Liangliang,Wang, Zhu,Pan, Chunxu,Xiao, Wei,Cho ,, Kyeongjae WILEY‐VCH Verlag 2013 Chemphyschem Vol.14 No.5

<P><B>Abstract</B></P><P>The effect of hydrogen on the adsorption and dissociation of the oxygen molecule on a TiO<SUB>2</SUB> anatase (001) surface is studied by first‐principles calculations coupled with the nudged elastic band (NEB) method. Hydrogen adatoms on the surface can increase the absolute value of the adsorption energy of the oxygen molecule. A single H adatom on an anatase (001) surface can lower dramatically the dissociation barrier of the oxygen molecule. The adsorption energy of an O<SUB>2</SUB> molecule is high enough to break the OO bond. The system energy is lowered after dissociation. If two H adatoms are together on the surface, an oxygen molecule can be also strongly adsorbed, and the adsorption energy is high enough to break the OO bond. However, the system energy increases after dissociation. Because dissociation of the oxygen molecule on a hydrogenated anatase (001) surface is more efficient, and the oxygen adatoms on the anatase surface can be used to oxidize other adsorbed toxic small gas molecules, hydrogenated anatase is a promising catalyst candidate.</P>

Structure evolution in carbon molecular sieve membranes derived from binaphthol-6FDA polyimide and their gas separation performance

Guoxiong Deng,Yilei Wang,Xueping Zong,Jiangzhou Luo,Xuezhen Wang,Chunxue Zhang,Song Xue 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.94 No.-

Here we reported a causal relationship between the molecular structure of binaphthol-based polyimideprecursor and the pore-size distribution of the derived carbon membrane. The binaphthol-basedpolyamide acid is synthesized from 2,20-diol-1,10-binaphthyl-6,60-diamine and 4,40-(hexafluoroisopro-pylidene)diphthalic anhydride (6FDA). Then, an azeotropic imidiaztion method was used to synthesizethe polyimide with naphthol groups (XS1). When the imidization is carried out by using acetic anhydride,the polyimide with acetyl groups (XS4) is achieved. The CMS membranes prepared by pyrolyzing XS1 andXS4 at 500, 550, and 600 ℃ are named using the temperature as the suffix, such as XS1-500. Their poreevolution has been investigated using TGA, FTIR, XRD, and Raman measurements. The trimodal pore-sizedistribution is in the carbon molecular sieve (CMS) membranes derived from XS4 and the CMS onesderived from XS1 exhibit a bimodal pore structure. Among them, XS4-500 exhibits the highest gaspermeabilities of 3332 barrer for CO2, 773 barrer for O2, and 119 barrer for N2. XS1-500 only affords theCO2, O2, and N2 permeabilities of 1086, 230, and 30.2 barrer. The esterification of naphthol not justdisturbs the hydrogen bonds between polyimide chains but also affects the pore generation of thederived CMS membranes. Our work provides an effective way to enhance the gas permeability of a CMSmembrane derived from the binaphthol-based polyimide.

MiR-144-3p and Its Target Gene β-Amyloid Precursor Protein Regulate 1-Methyl-4-Phenyl-1,2-3,6-Tetrahydropyridine-Induced Mitochondrial Dysfunction

Li, Kuo,Zhang, Junling,Ji, Chunxue,Wang, Lixuan Korean Society for Molecular and Cellular Biology 2016 Molecules and cells Vol.39 No.7

MicroRNAs (miRNAs) have been reported to be involved in many neurodegenerative diseases. The present study focused on the role of hsa-miR-144-3p in one of the neuro-degenerative diseases, Parkinson's disease (PD). Our study showed a remarkable down-regulation of miR-144-3p expression in 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-treated SH-SY5Y cells. MiR-144-3p was then overexpressed and silenced in human SH-SY5Y cells by miRNA-mimics and miRNA-inhibitor transfections, respectively. Furthermore, ${\beta}$-amyloid precursor protein (APP) was identified as a target gene of miR-144-3p via a luciferase reporter assay. We found that miR-144-3p overexpression significantly inhibited the protein expression of APP. Since mitochondrial dysfunction has been shown to be one of the major pathological events in PD, we also focused on the role of miR-144-3p and APP in regulating mitochondrial functions. Our study demonstrated that up-regulation of miR-144-3p increased expression of the key genes involved in maintaining mitochondrial function, including peroxisome proliferator-activated receptor ${\gamma}$ coactivator-$1{\alpha}$(PGC-$1{\alpha}$), nuclear respiratory factor 1 (NRF-1) and mitochondrial transcription factor A (TFAM). Moreover, there was also a significant increase in cellular ATP, cell viability and the relative copy number of mtDNA in the presence of miR-144-3p overexpression. In contrast, miR-144-3p silencing showed opposite effects. We also found that APP overexpression significantly decreased ATP level, cell viability, the relative copy number of mtDNA and the expression of these three genes, which reversed the effects of miR-144-3p overexpression. Taken together, these results show that miR-144-3p plays an important role in maintaining mitochondrial function, and its target gene APP is also involved in this process.