Microenvironmental interplay predominated by Aspergillus cvjetkovicii abates fungal pathogen incidence in paddy environment

Xiaoyan Fan,Haruna Matsumoto,Yue Wang,Yang Hu,Yufei Liu,Hongda Fang,artosz Nitkiewicz,Sharon Yu Ling Lau,Qiangwei Wang,Hua Fang,Mengeen Wang 대한환경공학회 2019 대한환경공학회 학술발표논문집 Vol.2019 No.-

DnaJ of Streptococcus suis Type 2 Contributes to Cell Adhesion and Thermotolerance

Zhang, Xiaoyan,Jiang, Xiaowu,Yang, Ling,Fang, Lihua,Shen, Hongxia,Lu, Xingmeng,Fang, Weihuan The Korean Society for Microbiology and Biotechnol 2015 Journal of microbiology and biotechnology Vol.25 No.6

To examine if the molecular chaperone DnaK operon proteins of Streptococcus suis type 2 (SS2) are involved in adhesion to host cells, the abundance values of these proteins from the surface of two SS2 strains of different adhesion capability were compared. Their roles in growth and adhesion to human laryngeal epithelial cell line HEp-2 cells were investigated on SS2 strain HA9801 and its mutants with DnaK operon genes partially knocked-out (PKO mutant) under heat stress. The major difference was that DnaJ was more abundant in strain HA9801 than in strain JX0811. Pretreatment of the bacteria with hyperimmune sera to DnaJ, but not with those to other proteins, could significantly reduce SS2 adhesion to HEp-2 cells. PKO of dnaJ g ene resulted in decreased SS2 growth at 37℃ and 42℃, and reduced its adhesion to HEp-2 cells. The wild-type strain stressed at 42℃ had increased expression of DnaJ on its surface and elevated adhesion to HEp-2 cells, which was also inhibitable by DnaJ specific antiserum. These results indicate that the DnaJ of S. suis type 2 is important not only for thermotolerance but also for adhesion to host cells. Because DnaJ expression is increased upon temperature upshift with increased exposure on the bacterial surface, the febrile conditions of the cases with systemic infections might help facilitate bacterial adhesion to host cells. DnaJ could be one of the potential candidates as a subunit vaccine because of its good immunogenicity.

Crosslinked Ionic Alginate and Cellulose-based Hydrogels for Photoresponsive Drug Release Systems

Fang Zhou,Shaohua Wu,Chris Rader,Jianwei Ma,Shaojuan Chen,Xiaoyan Yuan,E Johan Foster 한국섬유공학회 2020 Fibers and polymers Vol.21 No.1

In this work, photosensitive alginate and cellulose-based hydrogels with interpenetrating polymer networks weresuccessfully prepared from alginate, TEMPO-oxidized cellulose nanofibers (TEMPO-CNFs) and polyacrylamide,crosslinked by both Fe3+ and N,N'-methylenebis-acrylamide. The obtained hydrogels showed a clear relationship between themechanical properties and the content of the TEMPO-CNFs. The results indicated that the mechanical properties ofcrosslinked hydrogels were enhanced with the mass ratio of TEMPO-CNFs and alginate increased from 1/2 to 2. Moreover,the crosslinked ionic alginate and cellulose-based hydrogels with various TEMPO-CNFs contents exhibited aninterconnected porous morphology with an average pore size of ca. 130 μm, and demonstrated an increased cumulativerelease amount of BSA drugs under the ultraviolet irradiation. This study demonstrated that the as-prepared photoresponsivehydrogels would have a potential application as local drug release systems for wound dressings.

ON THE NONLINEAR MATRIX EQUATION X + ∑m i=1 A iX−qAi = Q(0 < q 1)

Xiaoyan Yin,Ruiping Wen,Liang Fang 대한수학회 2014 대한수학회보 Vol.51 No.3

In this paper, the nonlinear matrix equation X + m ∑ i=1 A∗ i X−qAi = Q (0 < q 1) is investigated. Some necessary conditions and sufficient conditions for the existence of positive definite solutions for the matrix equation are derived. Two iterative methods for the maximal positive definite solution are proposed. A perturbation estimate and an explicit expression for the condition number of the maximal positive definite solution are obtained. The theoretical results are illustrated by numerical examples.

On positive definite solutions of a class of nonlinear matrix equation

Liang Fang,San-Yang Liu,Xiaoyan Yin 대한수학회 2018 대한수학회보 Vol.55 No.2

This paper is concerned with the positive definite solutions of the nonlinear matrix equation $X-A^{*}\bar{X}^{-1}A=Q$, where $A, Q$ are given complex matrices with $Q$ positive definite. We show that such a matrix equation always has a unique positive definite solution and if $A$ is nonsingular, it also has a unique negative definite solution. Moreover, based on Sherman-Morrison-Woodbury formula, we derive elegant relationships between solutions of $X-A^{*}\bar{X}^{-1}A=I$ and the well-studied standard nonlinear matrix equation $Y+B^{*}Y^{-1}B=Q$, where $B, Q$ are uniquely determined by $A$. Then several effective numerical algorithms for the unique positive definite solution of $X-A^{*}\bar{X}^{-1}A=Q$ with linear or quadratic convergence rate such as inverse-free fixed-point iteration, structure-preserving doubling algorithm, Newton algorithm are proposed. Numerical examples are presented to illustrate the effectiveness of all the theoretical results and the behavior of the considered algorithms.

ON THE NONLINEAR MATRIX EQUATION $X+\sum_{i=1}^{m}A_i^*X^{-q}A_i=Q$(0<q≤1)

Yin, Xiaoyan,Wen, Ruiping,Fang, Liang Korean Mathematical Society 2014 대한수학회보 Vol.51 No.3

In this paper, the nonlinear matrix equation $$X+\sum_{i=1}^{m}A_i^*X^{-q}A_i=Q(0<q{\leq}1)$$ is investigated. Some necessary conditions and sufficient conditions for the existence of positive definite solutions for the matrix equation are derived. Two iterative methods for the maximal positive definite solution are proposed. A perturbation estimate and an explicit expression for the condition number of the maximal positive definite solution are obtained. The theoretical results are illustrated by numerical examples.

GBA inhibition suppresses ovarian cancer growth, survival and receptor tyrosine kinase AXL-mediated signaling pathways

Gang Wang,Baisha Ouyang,Fang Jing,Xiaoyan Dai 대한약리학회 2023 The Korean Journal of Physiology & Pharmacology Vol.27 No.1

The poor outcome of advanced ovarian cancer under conventional therapy necessitates new strategies to improve therapeutic efficacy. β-glucosidase (encoded by GBA) is a lysosomal enzyme and is involved in sphingolipids metabolism. Recent studies revealed that β-glucosidase plays a role in cancer development and chemoresistance. In this work, we systematically evaluated the expression and role of GBA in ovarian cancer. Our work demonstrates that inhibition of β-glucosidase has therapeutic potential for ovarian cancer. Gene Expression Profiling Interactive Analysis database, western blot and immunohistochemistry analyses of patient samples demonstrated that GBA mRNA and protein expression levels were significantly increased in ovarian cancer compared to normal tissues. Functional studies using gainof- function and loss-of-function approaches demonstrated that GBA overexpression did not affect growth and migration but alleviated cisplatin’s efficacy in ovarian cancer cells. In addition, GBA depletion resulted in growth inhibition, apoptosis induction, and enhancement of cisplatin’s efficacy. Of note, we found that GBA inhibition specifically decreased receptor tyrosine kinase AXL level, leading to the suppression of AXL-mediated signaling pathways. Our data suggest that GBA represents a promising target to inhibit AXL signaling and overcome cisplatin resistance in ovarian cancer.

Catabolite Control Protein A of Streptococcus suis Type 2 Contributes to Sugar Metabolism and Virulence

Yulong Tang,Wei Wu,Xiaoyan Zhang,Zhongyan Lu,Jianshun Chen,Weihuan Fang 한국미생물학회 2012 The journal of microbiology Vol.50 No.6

Catabolite control protein A (CcpA) is the major transcriptional regulator in carbon catabolite repression in several Gram-positive bacteria. We attempted to characterize the role of a CcpA homologue of Streptococcus suis type 2 in sugar metabolism and virulence. Addition of glucose or sucrose to the defined medium significantly reduced the activity of raffinose-inducible α-galactosidase, cellobiose-inducible β-glucosidase, and maltose-inducible α-glucosidase of the wildtype strain by about 9, 4, and 2-3 fold, respectively. Deletion of ccpA substantially derepressed the effects of repressing sugars on α-galactosidase or β-glucosidase activity. The ccpA deletion mutant showed reduced expression of virulence genes sly and eno (P<0.05), decreased adhesion to and invasion into endothelial cells (P<0.05), and attenuated virulence to mice with significant reduction of death rate and bacterial burden in organs, as compared to the wild-type strain. Both the in vitro and in vivo defect phenotypes were reversible by ccpA complementation. Thus, this study shows that CcpA of S. suis type 2 plays an important role in carbon catabolite repression and virulence.

Anti-proliferation and pro-apoptosis effects of miR-582-5p in chronic lymphocytic leukemia via targeting HNRNPA1 and suppression of NF-κB

Wang Zengsheng,Li Yan,Kuang Xiaochuan,Guo Fang,Lang Tao,Mao Min,Zhang Xiaoyan,Yang Haiqing 대한독성 유전단백체 학회 2021 Molecular & cellular toxicology Vol.17 No.3

Background MicroRNAs (miRNAs) function as post-transcriptional mediators for genes involved in cancer progression, including chronic lymphocytic leukemia. MiR-582-5p has been identified as a tumor suppressor in various tumors. The antioncogenic role of miR-582-5p was then validated in this study. Objective Mononuclear cells were isolated from peripheral blood samples of patients with chronic lymphocytic leukemia and healthy donors. Expression of miR-582-3p in the mononuclear cells was examined by qRT-PCR. CCK8 assay was performed to detect cell viability, and cell cycle and apoptosis were evaluated by flow cytometry. Dual luciferase activity assay was performed to determine the targeting relationship between miR-582-3p and HNRNPA1, and western blot was performed to unravel the mechanism. Results MiR-582-5p was reduced in mononuclear cells of patients with chronic lymphocytic leukemia compared to healthy donors. Forced miR-582-5p expression reduced cell viability, and promoted apoptosis of chronic lymphocytic leukemia cells. Cell cycle was arrested in G0/G1 phase via miR-582-5p mimic. MiR-582-5p bound to HNRNPA1 (heterogeneous nuclear ribonucleoprotein A1) and down-regulated its expression. Silence of HNRNPA1 decreased cell viability, promoted apoptosis, and blocked cell cycle at G0/G1 phase through up-regulation of IκBα (IkappaBalpha). Moreover, HNRNPA1 silencing attenuated the promotive effect induced by miR-582-5p inhibitor on the progression of chronic lymphocytic leukemia. Conclusion MiR-582-5p demonstrated anti-proliferative and pro-apoptotic roles in chronic lymphocytic leukemia cell growth via down-regulation of HNRNPA1 and up-regulation of IκBα, thus inactivating NF-κB. Background MicroRNAs (miRNAs) function as post-transcriptional mediators for genes involved in cancer progression, including chronic lymphocytic leukemia. MiR-582-5p has been identified as a tumor suppressor in various tumors. The antioncogenic role of miR-582-5p was then validated in this study. Objective Mononuclear cells were isolated from peripheral blood samples of patients with chronic lymphocytic leukemia and healthy donors. Expression of miR-582-3p in the mononuclear cells was examined by qRT-PCR. CCK8 assay was performed to detect cell viability, and cell cycle and apoptosis were evaluated by flow cytometry. Dual luciferase activity assay was performed to determine the targeting relationship between miR-582-3p and HNRNPA1, and western blot was performed to unravel the mechanism. Results MiR-582-5p was reduced in mononuclear cells of patients with chronic lymphocytic leukemia compared to healthy donors. Forced miR-582-5p expression reduced cell viability, and promoted apoptosis of chronic lymphocytic leukemia cells. Cell cycle was arrested in G0/G1 phase via miR-582-5p mimic. MiR-582-5p bound to HNRNPA1 (heterogeneous nuclear ribonucleoprotein A1) and down-regulated its expression. Silence of HNRNPA1 decreased cell viability, promoted apoptosis, and blocked cell cycle at G0/G1 phase through up-regulation of IκBα (IkappaBalpha). Moreover, HNRNPA1 silencing attenuated the promotive effect induced by miR-582-5p inhibitor on the progression of chronic lymphocytic leukemia. Conclusion MiR-582-5p demonstrated anti-proliferative and pro-apoptotic roles in chronic lymphocytic leukemia cell growth via down-regulation of HNRNPA1 and up-regulation of IκBα, thus inactivating NF-κB.

Grinding Damage of BK7 using Copper-Resin Bond Coarse-Grained Diamond Wheel

Qingliang Zhao,Junyun Chen,Haitao Huang,Xiaoyan Fang 한국정밀공학회 2011 International Journal of Precision Engineering and Vol. No.

Coarse-grained wheels can realize high efficient grinding of optical glass. However, the serious surface and subsurface damage will be inevitably introduced by the coarse-grained wheels. In this paper, the grinding damage of a copper-resin bond coarse-grained diamond wheel with grain size of 150μm was investigated on optical glass BK7. The wheel was first properly trued with a metal bond diamond wheel, then pre-dressing for the wheel and grinding experiments are carried out on a precision grinder assisted with electrolytic in process dressing (ELID) method. The surface roughness (Ra) of ground surface was measured using an atomic force microscope (AFM) and the surface topography were imaged by a white light interferometer (WLI) and the AFM. The subsurface damage level of ground surface was evaluated by means of both MRF spot method and taper polishing-etching method, in term of the biggest depth of subsurface damage, distribution of micro defects beneath the ground surface, the cluster depth of subsurface damage, relationship between subsurface damage (SSD)and PV surface roughness (SR), propagating distance and pattern of cracks beneath the ground surface. Experimental results indicate that a well conditioned copper-resin bond coarse-grained diamond wheel on a precision grinder can generate good surface quality of Ra less than 50nm and good subsurface integrity with SSD depth less than 3.5μm for optical glass BK7.