Fabrication and Analyses of Bionic Polymer Lens System

Xuan Yin Wang,Dan Liang,Feng Tang,Jia Wei Du 한국고분자학회 2016 폴리머 Vol.40 No.2

In this paper, we design and fabricate a bionic solid tunable lens which is mainly made of polymer materials. The lens focal length can be changed flexibly by pressing the lens surface to alter the curvature radius. A detailed description of the lens structure, materials and fabrication process is presented. The lens mechanical properties and deformation process are simulated and analyzed using Ansys software. A precise experimental device based on a stepping motor is fabricated to measure and analyze the relationship between the displacement load and focal length. The lens focal length can be reversibly changed from 31.8 to 14.1 mm under 1 mm variation of displacement load. This paper offers a feasible way for the design, fabrication, and actuation of the solid tunable lens, which can be used in various machine vision apparatus.

Lactate exacerbates lung damage induced by nanomicroplastic through the gut microbiota–HIF1a/PTBP1 pathway

Xuan Lihui,Xu Zheng,Luo Jinhua,Yin Wang,Yan Yuhui,Qu Can,Xie Zuozhong,Skonieczna Magdalena,Zhou Ping-Kun,Huang Ruixue 생화학분자생물학회 2023 Experimental and molecular medicine Vol.55 No.-

Exposure to nanomicroplastics (nano-MPs) can induce lung damage. The gut microbiota is a critical modulator of the gut–lung axis. However, the mechanisms underlying these interactions have not been elucidated. This study explored the role of lactate, a key metabolite of the microbiota, in the development of lung damage induced by nano-MPs (LDMP). After 28 days of exposure to nano-MPs (50–100 nm), mice mainly exhibited damage to the lungs and intestinal mucosa and dysbiosis of the gut microbiota. Lactate accumulation was observed in the lungs, intestines and serum and was strongly associated with the imbalance in lactic acid bacteria in the gut. Furthermore, no lactate accumulation was observed in germ-free mice, while the depletion of the gut microbiota using a cocktail of antibiotics produced similar results, suggesting that lactate accumulation in the lungs may have been due to changes in the gut microbiota components. Mechanistically, elevated lactate triggers activation of the HIF1a/PTBP1 pathway, exacerbating nano-MP-induced lung damage through modulation of the epithelial–mesenchymal transition (EMT). Conversely, mice with conditional knockout of Ptbp1 in the lungs (Ptbp1flfl) and PTBP1-knockout (PTBP1-KO) human bronchial epithelial (HBE) cells showed reversal of the effects of lactate through modulation of the HIF1a/PTBP1 signaling pathway. These findings indicate that lactate is a potential target for preventing and treating LDMP.

Anti-tumor Activity and Apoptosis-regulation Mechanisms of Bufalin in Various Cancers: New Hope for Cancer Patients

Yin, Pei-Hao,Liu, Xuan,Qiu, Yan-Yan,Cai, Jian-Feng,Qin, Jian-Min,Zhu, Hui-Rong,Li, Qi Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.11

The induction of apoptosis in target cells is a key mechanism for most anti-tumor therapies. Bufalin is a cardiotonic steroid that has the potential to induce differentiation and apoptosis of tumor cells. Research on bufalin has so far mainly involved leukemia, prostate cancer, gastric cancer and liver cancer, and has been confined to in vitro studies. The bufadienolides bufalin and cinobufagin have been shown to induce apoptosis in a wide spectrum of cancer cell. The present article reviews the anticancer effects of bufalin. It induces apoptosis of lung cancer cells via the PI3K/Akt pathway and also suppressed the proliferation of human non-small cell lung cancer A549 cell line in a time and dose dependent manner. Bufalin, bufotalin and gamabufotalin, key bufadienolides, significantly sensitize human breast cancer cells with differing ER-alpha status to apoptosis induction by the TNF-related apoptosis-inducing ligand (TRAIL). In addition, bufadienolides induce prostate cancer cell apoptosis more significantly than that in breast epithelial cell lines. Similar effects have been observed with hepatocellular carcinoma (HCC) but the detailed molecular mechanisms of inducing apoptosis in this case are still unclear. Bufalin exerts profound effects on leukemia therapy in vitro. Results of multiple studies indicate that bufalin has marked anti-tumor activities through its ability to induce apoptosis. Large-scale randomized, double-blind, placebo or positive drug parallel controlled studies are now required to confirm the efficacy and apoptosis-inducing potential of bufalin in various cancers in the cliniucal setting.

Synergistic effect of micro-textures and MoS2 on the tribological properties of PTFE film against GCr15 bearing steel

Xuan Xie,Xijun Hua,Jianhua Li,Xiaobin Cao,Zhixiang Tian,Rui Peng,Bifeng Yin,Peiyun Zhang 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.5

To enhance the friction and wear resistance of GCr15/PTFE sliding contact surfaces, the synergistic lubrication effect of micro-textures and solid lubricants were studied in this paper. Micro-textures were processed on GCr15 samples by Nd:YAG laser, which were filled with MoS 2 . Tribological performance tests were carried out on a Rtec-MFT 5000 tester. Tribological properties were optimal with the textures density of 20 % and depth of 9 μm. A continuous composite solid lubricating film was formed by PTFE and MoS 2 . As load increases, friction coefficient of the sample shows a rapid decline and then stabilizes. With the increase of reciprocating frequency, friction curve of the sample shows a trend of slight fluctuation. When frequency is 2.7 Hz, friction coefficient is the lowest. Tribological properties of PTFE/GCr15 contact surfaces could be significantly optimized by micro-textures and MoS 2 , which performs favorable prospect of engineering application such as guide rails, bearings, machinery seal, etc.

Characterization and Expression Profile Analysis of a New cDNA Encoding Taxadiene Synthase from Taxus media

Guo Yin Kai,Ling Xia Zhao,Lei Zhang,Zhu Gang Li,Bin Hui Guo,Dong Li Zhao,Xiao Fen Sun,Zhi Qi Miao,Ke Xuan Tang 한국생활환경학회 2005 BMB Reports Vol.38 No.6

Genetically Encoded Biosensor Engineering for Application in Directed Evolution

Mao Yin,Huang Chao,Zhou Xuan,Han Runhua,Deng Yu,Zhou Shenghu 한국미생물·생명공학회 2023 Journal of microbiology and biotechnology Vol.33 No.10

Although rational genetic engineering is nowadays the favored method for microbial strain improvement, building up mutant libraries based on directed evolution for improvement is still in many cases the better option. In this regard, the demand for precise and efficient screening methods for mutants with high performance has stimulated the development of biosensor-based highthroughput screening strategies. Genetically encoded biosensors provide powerful tools to couple the desired phenotype to a detectable signal, such as fluorescence and growth rate. Herein, we review recent advances in engineering several classes of biosensors and their applications in directed evolution. Furthermore, we compare and discuss the screening advantages and limitations of two-component biosensors, transcription-factor-based biosensors, and RNA-based biosensors. Engineering these biosensors has focused mainly on modifying the expression level or structure of the biosensor components to optimize the dynamic range, specificity, and detection range. Finally, the applications of biosensors in the evolution of proteins, metabolic pathways, and genome-scale metabolic networks are described. This review provides potential guidance in the design of biosensors and their applications in improving the bioproduction of microbial cell factories through directed evolution.

Seroprevalence and Risk Factors of Fascioliasis in Yaks, Bos grunniens, from Three Counties of Gansu Province, China

Xiao-Xuan Zhang,Sheng-Yong Feng,Jian-Gang Ma,Wen-Bin Zheng,Ming-Yang Yin,Si-Yuan Qin,Dong-Hui Zhou,Quan Zhao,Xing-Quan Zhu 대한기생충학열대의학회 2017 The Korean Journal of Parasitology Vol.55 No.1

Lipase Inactive Mutant of PLC-γ1 Regulates NGF-induced Neurite Outgrowth Via Enzymatic Activity and Regulation of Cell Cycle Regulatory Proteins

Le Xuan Nguyen, Truong,Ahn, Jee-Yin Korean Society for Biochemistry and Molecular Biol 2007 Journal of biochemistry and molecular biology Vol.40 No.6

Src homology (SH) domains of phospholipase C-$\gamma1$ (PLC-$\gamma1$) impair NGF-mediated PC12 cells differentiation. However, whether the enzymatic activity is also implicated in this process remains elusive. Here, we report that the enzymatic activity of phospholipase C-$\gamma1$ (PLC-$\gamma1$) is at least partially involved to the blockage of neuronal differentiation via an abrogation of MAPK activation, as well as sustained Akt activation. By contrast, Overexpression of WT-PLC-$\gamma1$ exhibited sustained NGF-induced MAPK activation, and triggered transient Akt activation resulting in profound inhibition of neurite outgrowth. However, lipase-inactive mutant (LIM) PLC-$\gamma1$ cells fail to suppress neurite outgrowth, although it contains intact SH domains, specifically enhancing the expression of cyclin D1 and p21 proteins, which regulate the function of retinoblastoma Rb protein. These observations show that the lipase inactive mutant of PLC-$\gamma1$ does not alter NGF-induced neuronal differentiation via enzymatic inability and the modulation of cell cycle regulatory proteins independent on SH3 domain.

Nonlinear low-velocity impact response of graphene platelets reinforced metal foams doubly curved shells

Hao-Xuan Ding,Yi-Wen Zhang,Yin-Ping Li,Gui-Lin She 국제구조공학회 2023 Steel and Composite Structures, An International J Vol.49 No.3

Due to the fact that the nonlinear low-velocity impact response of graphene platelets reinforced metal foams (GPLRMF) doubly curved shells have not been investigated in the existing works, this paper aims to solve this issue. Using Reddy's high-order shear deformation theory (HSDT), the nonlinear governing equations of GPLRMF doubly curved shells are obtained by Euler-Lagrange method, discretized by Galerkin principle, and solved by the fourth-order Runge-Kutta method to obtain the impact force and central deflection. The nonlinear Hertz contact law is applied to determine the contact force. Finally, the impacts of graphene platelets (GPLs) distribution pattern, porosity distribution form, porosity coefficient, damping coefficient, impact parameters (radius and initial velocity), GPLs weight fraction, pre-stressing force and different shell types on the low-velocity impact curves are analyzed. It can be found that, among the four shell structures, the impact resistance of spherical shell is the best, while that of cylindrical shell is the worst.

Effects of Lower Dietary Lysine and Energy Content on Carcass Characteristics and Meat Quality in Growing-finishing Pigs

Zhang, Jinxiao,Yin, Jingdong,Zhou, Xuan,Li, Fengna,Ni, Jianjun,Dong, Bing Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.12

Fifty-four PIC barrows were used to evaluate the effects of lower dietary lysine content and energy level on carcass characteristics and meat quality in slaughter pigs. Pigs were allotted to one of three treatments by body weight with six replicate pens in each treatment. The dietary treatments for body weights of 20-50 kg, 50-80 kg and 80-90 kg were as follows, respectively: control diet (digestible energy 14.22 MJ/kg, lysine/DE 0.67 g/MJ, 0.53 g/MJ and 0.42 g/MJ); a low lysine group (digestible energy 14.22 MJ/kg, lysine/DE 0.49, 0.38 and 0.30 g/MJ); and a low lysine-low energy group or low nutrient group (digestible energy 13.11 MJ/kg, lysine/DE 0.49, 0.38 and 0.30 g/MJ). The daily weight gain, daily feed intake and feed efficiency were calculated in the overall growth period (nearly 12 weeks). Meanwhile, carcass characteristics and meat quality were evaluated at 60 and 90 kg body weight respectively. During the overall growth trial, lowering dietary lysine and nutrient level both decreased weight gain (p<0.05) and feed efficiency (p<0.01). At 60 kg body weight, decreasing dietary lysine and nutrient level noticeably decreased dressing percentage (p<0.01) and back fat depth at last rib of PIC pigs (p<0.01), but enhanced marbling scores (p<0.10), intramuscular fat content (p<0.10) and water loss rate (p<0.01) of the longissimus dorsi muscle. At 90 kg body weight, lean percentage (p<0.01) was evidently reduced by both lowering lysine content and nutrient level in the diet. However, the shoulder back fat depth (p<0.05) and marbling scores of the loin eye muscle (p<0.05) were increased; Lowering dietary nutrient level could improve back fat depth of 10th rib (p<0.01) and last rib (p<0.01), intramuscular fat content (p<0.10), redness (p<0.01) and water loss rate of the loin eye muscle (p<0.05), but decrease loin area (p<0.05). Finally, when comparing the 60 kg and 90 kg slaughter weights, it was found that the shoulder back fat depth (p<0.01, p<0.10), 6th-7th rib (p<0.01, p<0.01), 10th-rib (p<0.01, p<0.01) and last rib back fat depth (p<0.01, p<0.01) of the low lysine and low nutrient group were all obviously increased comparing with the control group. Taken together, the results showed that decreasing dietary lysine content and nutrient level increased intramuscular fat content and water loss rate of longissimus dorsi muscle; On the other hand, both lowering dietary lysine and nutrient level markedly compensated to increase back fat deposition in the later finishing period (body weight from 60 to 90 kg) in contrast to the control group.