Amelioration of Bleomycin-induced Pulmonary Fibrosis of Rats by an Aldose Reductase Inhibitor, Epalrestat

Xianwei Li,Yuanyuan Shen,Yining Lu,Jieren Yang 대한생리학회-대한약리학회 2015 The Korean Journal of Physiology & Pharmacology Vol.19 No.5

Aldose reductase (AR) is known to play a crucial role in the mediation of diabetic and cardiovascular complications. Recently, several studies have demonstrated that allergen-induced airway remodeling and ovalbumin-induced asthma is mediated by AR. Epalrestat is an aldose reductase inhibitor that is currently available for the treatment of diabetic neuropathy. Whether AR is involved in pathogenesis of pulmonary fibrosis and whether epalrestat attenuates pulmonary fibrosis remains unknown. Pulmonary fibrosis was induced by intratracheal instillation of bleomycin (5 mg/kg) in rats. Primary pulmonary fibroblasts were cultured to investigate the proliferation by BrdU incorporation method and flow cytometry. The expression of AR, TGF-β₁, α-SMA and collagen I was analyzed by immunohis-tochemisty, real-time PCR or western blot. In vivo, epalrestat treatment significantly ameliorated the bleomycin-mediated histological fibrosis alterations and blocked collagen deposition concomitantly with reversing bleomycin-induced expression up-regulation of TGF-β₁, AR, α-SMA and collagen I (both mRNA and protein). In vitro, epalrestat remarkably attenuated proliferation of pulmonary fibroblasts and expression of α-SMA and collagen I induced by TGF-β₁, and this inhibitory effect of epalrestat was accompanied by inhibiting AR expression. Knockdown of AR gene expression reversed TGF-β₁-induced proliferation of fibroblasts, up-regulation of α-SMA and collagen I expression. These findings suggest that AR plays an important role in bleomycin-induced pulmonary fibrosis, and epalrestat inhibited the progression of bleomycin-induced pulmonary fibrosis is mediated via inhibiting of AR expression.

Amelioration of Bleomycin-induced Pulmonary Fibrosis of Rats by an Aldose Reductase Inhibitor, Epalrestat

Li, Xianwei,Shen, Yuanyuan,Lu, Yining,Yang, Jieren The Korean Society of Pharmacology 2015 The Korean Journal of Physiology & Pharmacology Vol.19 No.5

Aldose reductase (AR) is known to play a crucial role in the mediation of diabetic and cardiovascular complications. Recently, several studies have demonstrated that allergen-induced airway remodeling and ovalbumin-induced asthma is mediated by AR. Epalrestat is an aldose reductase inhibitor that is currently available for the treatment of diabetic neuropathy. Whether AR is involved in pathogenesis of pulmonary fibrosis and whether epalrestat attenuates pulmonary fibrosis remains unknown. Pulmonary fibrosis was induced by intratracheal instillation of bleomycin (5 mg/kg) in rats. Primary pulmonary fibroblasts were cultured to investigate the proliferation by BrdU incorporation method and flow cytometry. The expression of AR, TGF-${\beta}_1$, ${\alpha}$-SMA and collagen I was analyzed by immunohistochemisty, real-time PCR or western blot. In vivo, epalrestat treatment significantly ameliorated the bleomycin-mediated histological fibrosis alterations and blocked collagen deposition concomitantly with reversing bleomycin-induced expression up-regulation of TGF-${\beta}_1$, AR, ${\alpha}$-SMA and collagen I (both mRNA and protein). In vitro, epalrestat remarkably attenuated proliferation of pulmonary fibroblasts and expression of ${\alpha}$-SMA and collagen I induced by TGF-${\beta}_1$, and this inhibitory effect of epalrestat was accompanied by inhibiting AR expression. Knockdown of AR gene expression reversed TGF-${\beta}_1$-induced proliferation of fibroblasts, up-regulation of ${\alpha}$-SMA and collagen I expression. These findings suggest that AR plays an important role in bleomycin-induced pulmonary fibrosis, and epalrestat inhibited the progression of bleomycin-induced pulmonary fibrosis is mediated via inhibiting of AR expression.

Selective Production of Aromatic Aldehydes from Heavy Fraction of Bio-oil via Catalytic Oxidation

Li, Yan,Chang, Jie,Ouyang, Yong,Zheng, Xianwei Korean Chemical Society 2014 Bulletin of the Korean Chemical Society Vol.35 No.6

High value-added aromatic aldehydes (e.g. vanillin and syringaldehyde) were produced from heavy fraction of bio-oil (HFBO) via catalytic oxidation. The concept is based on the use of metalloporphyin as catalyst and hydrogen peroxide ($H_2O_2$) as oxidant under alkaline condition. The biomimetic catalyst cobalt(II)-sulfonated tetraphenylporphyrin ($Co(TPPS_4)$) was prepared and characterized. It exhibited relative high activity in the catalytic oxidation of HFBO. 4.57 wt % vanillin and 1.58 wt % syringaldehyde were obtained from catalytic oxidation of HFBO, compared to 2.6 wt % vanillin and 0.86 wt % syringaldehyde without $Co(TPPS_4)$. Moreover, a possible mechanism of HFBO oxidation using $Co(TPPS_4)/H_2O_2$ was proposed by the research of model compounds. The results showed that this is a promising and environmentally friendly method for production of aromatic aldehydes from HFBO under $Co(TPPS_4)/H_2O_2$ system.

Hydrate Management in Deadlegs: Effect of Header Temperature on Hydrate Deposition

Zhang, Xianwei,Lee, Bo Ram,Sa, Jeong-Hoon,Kinnari, Keijo J.,Askvik, Kjell M.,Li, Xiaoyun,Sum, Amadeu K. American Chemical Society 2017 ENERGY AND FUELS Vol.31 No.11

<P>Deadlegs in oil and gas production systems often encounter hydrate plugs by deposition. Temperature is generally known to be an important variable in hydrate formation, but the effects in deadlegs are not exactly known. This study focuses on the effects of the header temperature on the hydrate deposition in gas-filled vertical deadlegs at constant wall temperature. All experiments are conducted with a methane/ethane gas mixture at constant pressure. The pipe wall temperature is kept constant while considering different header temperatures. The tests show that the header temperature has a significant impact in the hydrate deposit growth rate and distribution in the deadleg. It is also found that the hydrate deposit can, in turn, change the temperature field inside the pipe. The header temperature or the pipe temperature field can be used to estimate the hydrate distribution in the deadleg. Under the right conditions, hydrates can form a restriction in the deadleg and its location is usually close to the boundary of a hydrate-stable region. The location of the restriction can be correlated to the header temperature. At 80 °C, the location is estimated to be 15–18 ID, and at 30 °C, the location is estimated to be 9–12 ID. The results of this study contribute to the understanding of the hydrate deposition mechanism in deadlegs.</P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ef7b02095'>ACS Electronic Supporting Info</A></P>

Selective Production of Aromatic Aldehydes from Heavy Fraction of Bio-oil via Catalytic Oxidation

Yan Li,Jie Chang,Yong Ouyang,Xianwei Zheng 대한화학회 2014 Bulletin of the Korean Chemical Society Vol.35 No.6

High value-added aromatic aldehydes (e.g. vanillin and syringaldehyde) were produced from heavy fraction of bio-oil (HFBO) via catalytic oxidation. The concept is based on the use of metalloporphyin as catalyst and hydrogen peroxide (H2O2) as oxidant under alkaline condition. The biomimetic catalyst cobalt(II)-sulfonated tetraphenylporphyrin (Co(TPPS4)) was prepared and characterized. It exhibited relative high activity in the catalytic oxidation of HFBO. 4.57 wt % vanillin and 1.58 wt % syringaldehyde were obtained from catalytic oxidation of HFBO, compared to 2.6 wt % vanillin and 0.86 wt % syringaldehyde without Co(TPPS4). Moreover, a possible mechanism of HFBO oxidation using Co(TPPS4)/H2O2 was proposed by the research of model compounds. The results showed that this is a promising and environmentally friendly method for production of aromatic aldehydes from HFBO under Co(TPPS4)/H2O2 system.

Alpha-Hemolysin from Staphylococcus aureus Obstructs Yeast-Hyphae Switching and Diminishes Pathogenicity in Candida albicans

Yu Xiaoyu,Mao Yinhe,Li Guangbo,Wu Xianwei,Xuan Qiankun,Yang Simin,Chen Xiaoqing,Cao Qi,Guo Jian,Guo Jinhu,Wu Wenjuan 한국미생물학회 2023 The journal of microbiology Vol.61 No.2

The use of antibiotics can disrupt the body’s natural balance and increase the susteptibility of patients towards fungal infections. Candida albicans is a dimorphic opportunistic fungal pathogen with niches similar to those of bacteria. Our aim was to study the interaction between this pathogen and bacteria to facilitate the control of C. albicans infection. Alpha-hemolysin (Hla), a protein secreted from Staphylococcus aureus, causes cell wall damage and impedes the yeast–hyphae transition in C. albicans. Mechanistically, Hla stimulation triggered the formation of reactive oxygen species that damaged the cell wall and mitochondria of C. albicans. The cell cycle was arrested in the G0/G1 phase, CDC42 was downregulated, and Ywp1 was upregulated, disrupting yeast hyphae switching. Subsequently, hyphae development was inhibited. In mouse models, C. albicans pretreated with Hla reduced the C. albicans burden in skin and vaginal mucosal infections, suggesting that S. aureus Hla can inhibit hyphal development and reduce the pathogenicity of candidiasis in vivo.

A Summary of Multicast Routing Algorithms in Wireless Mesh Networks

Liang Zhao,Changqing Gong,Xianwei Li,Guolong Chen 보안공학연구지원센터 2015 International Journal of Multimedia and Ubiquitous Vol.10 No.6

Wireless Mesh Network (WMN) presents us a key emerging technology which can construct the next generation wireless multi-hop network. It combines the advantages of both mobile ad-hoc network (MANET) and traditional fixed network. The applications of WMNs also attract significant industrial and academic attentions. As a vital function of network communication, multicast is normally applied to transmit data for high-definition video and gaming in WMNs. Therefore, the multicast routing algorithms are very important to the performance of group communication in WMNs. In this paper, we review a list of existing multicast routing algorithms in WMNs. Based on the findings, we also point out the open issues of multicast routing algorithms.

Scaffold Engineering with Flavone-Modified Biomimetic Architecture for Vascular Tissue Engineering Applications

Xie Chao,Guo Ting,Wang Wei,Li Gang,Cai Zhou,Chen Shen,Wang Xianwei,Liu Ziyu,Wang Zuyong 한국조직공학과 재생의학회 2022 조직공학과 재생의학 Vol.19 No.4

BACKGROUND: Vascular intimal hyperplasia (IH) is one of the key challenges in the clinical application of smalldiameter vascular grafts. Current tissue engineering strategies focus on vascularization and antithrombotics, yet few approaches have been developed to treat IH. Here, we designed a tissue-engineered vascular scaffold with portulaca flavonoid (PTF) composition and biomimetic architecture. METHOD: By electrospinning, PTF is integrated with biodegradable poly(e-caprolactone) (PCL) into a bionic vascular scaffold. The structure and functions of the scaffolds were evaluated based on material characterization and cellular biocompatibility. Human vascular smooth muscle cells (HVSMCs) were cultured on scaffolds for up to 14 days. RESULTS: The incorporation of PTF and preparation parameters during fabrication influences the morphology of the scaffold, including fibre diameter, structure, and orientation. Compared to the PCL scaffold, the scaffolds integrated with bioactive PTF show better hydrophilicity and degradability. HVSMCs seeded on the scaffold alongside the fibres exhibit fusiform-like shapes, indicating that the scaffold can provide contact guidance for cell morphology alterations. This study demonstrates that the PCL/PTF (9.1%) scaffold inhibits the excessive proliferation of HVSMCs without causing cytotoxicity. CONCLUSION: The study provides insights into the problem of restenosis caused by IH. This engineered vascular scaffold with complex function and preparation is expected to be applied as a substitute for small-diameter vascular grafts.

Functional Characterization of the Copper-Transporting P-Type ATPase Gene of Penicillium janthinellum Strain GXCR

Hongmin Lai,Changbin Sun,Huaying Tang,Xianwei Fan,Yili Ma,Youzhi Li 한국미생물학회 2009 The journal of microbiology Vol.47 No.6

Copper (Cu)-transporting P-type ATPase (CTPA) genes have been documented to play an important role in resistance to heavy metals. However, our understanding of roles of CTPA genes of the filamentous fungi was based only on sequence similarity prediction before. In a previous study, we isolated a Penicillum janthinellum strain GXCR of higher tolerance to Cu (200 mM). In this study, we cloned the partial cDNA of CTPA gene, named PcpA, from the strain GXCR. Sequence alignment indicated that the cloned cDNA sequence has the highest identity (94.4%) with a predictive CTPA gene of Aspergillus clavatus. The PcpA- encoded protein, termed PcpA, has classical functional domains of CTPAs, and shows differences from reported CTPAs in some specific sequence motifs and transmembrane regions. Expression of the PcpA was induced by extracellular Cu, cadmium (Cd), and silver (Ag). PcpA RNA interference (RNAi) mutants with a reduced level of PcpA mRNA were more sensitive to Cu, iron, Cd, and Ag than the wild-type (WT) strain GXCR. When grown in the presence of Cu, iron, and Cd, intracellular Cu and iron contents in the PcpA RNAi mutant were significantly (P<0.05) lower than those in the WT; However, intracellular Cd content in the mutant was significantly (P<0.05) higher than that in the WT. Taken together, it can be concluded that the PcpA functions in Cu uptake and homeostasis, iron uptake, and Cd export from the cytosol to the extracytosol.

Analysis of Undrained Shear Characteristics and Structural Damage of Granite Residual Soil

Song Yin,Pengfei Liu,Pan Yan,Xianwei Zhang,Xinming Li 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.9

Three-dimensional consolidation testing, scanning electron microscopy, and undrained triaxial testing of granite residual soil (GRS) in Shenzhen, China, were conducted. The effect of the structural strength of GRS was quantitatively analyzed using the method of comprehensive structure potential parameter description. The failure strength ratio of the soil decreases with increasing confining pressure, and it is approximately 1 when the confining pressure is higher than the yield stress (σs). The undrained shear strength (Su) of the undisturbed soil varies in stages with confining pressure σ3. The relationship between Su and σ3 for the reconstituted soil is approximated as a straight line through the origin. The soil’s comprehensive structure potential parameters (the structural contribution rates of the tangential shear modulus, mE, and the deviatoric stress, md) decrease linearly with increasing σ3. The mE and md sample values are similar under the same confining pressure. It is reasonable to use structure potential parameters to quantitatively evaluate the structure contribution rate of GRS. The microstructure is constantly adjusted, and the soil microstructure form for different confining pressures strongly correlates with its shear characteristics.