Research Articles : The Influence of Challenge on Cathepsin B and D Expression Patterns in the Silkworm Bombyx mori L

( Feng Yao Wu ),( Feng Ming Zou ),( Jun Qiang Jia ),( Sheng Peng Wang ),( Guo Zheng Zhang ),( Xi Jie Guo ),( Zhong Zheng Gui ) 한국잠사학회 2011 International Journal of Industrial Entomology Vol.23 No.1

Cathepsins are well-characterized proteases that are ubiquitously expressed in lysosomes. Previous work revealed that Bombyx mori cathepsins B and D are expressed in the fat body and undergo decomposition during larval-pupal metamorphosis. Quantitative RTPCR was performed to detect cathepsin gene expression at the transcription level when challenged by B. mori nuclear polyhedrosis virus (BmNPV), temperature and hormones (20-hydroxyecdysone (20E) and juvenile hormone analogue (JHA)). mRNAs encoding cathepsins B and D were significantly enhanced after the larvae were infected with BmNPV, and the peak of the induction appeared at 1 day before spinning. This attenuated the inducing effect on cathepsin expression caused by infection. Temperature shock induced cathepsin expression at the later stage of the 5th instar, and transcription levels varied with development stage and temperature. Cathepsin B and D mRNA expression in the fat body were significantly induced by JHA at the day before spinning, and with 20E, the expression reached a peak at the last day of the 5th instar. Cathepsin B and D mRNA expression exhibited detectable changes post-treatment, without significant differences between or among the hormone concentrations.

Notes : Radical Scavenging Hydroxyphenyl Ethanoic Acid Derivatives from a Marine-Derived Fungus

( Xi Feng Li ),( Se Kwon Kim ),( Jung Sook Kang ),( Hong Dae Choi ),( Byeng Wha Son ) 한국미생물 · 생명공학회 2006 Journal of microbiology and biotechnology Vol.16 No.4

Effect of Joint Stiffness on the Stability of Cable-braced Grid Shells

Xi Wang,Ruo-qiang Feng,Gui-rong Yan,Feng-cheng Liu,Wei-jia Xu 한국강구조학회 2016 International Journal of Steel Structures Vol.16 No.4

Bolted joints used in cable-braced grid shells are typically semi-rigid joints, and the joint stiffness has a significant effect on the stability of cable-braced grid shells. The effect of joint stiffness on the stability of cable-braced grid shells is studied in this paper. Based on the experimental results of improved bolted joints, finite element models of elliptic paraboloid cable-braced grid shells with bolted joints are established, and spring elements are used to simulate the joint stiffness. The effect of the joint stiffness on the nonlinear buckling load is studied by changing the joint stiffness. The main conclusions are as follows. First, the joint rotational stiffness has a significant effect on the failure mode. When the joint rotational stiffness is small to a certain extent, the failure mode of cable-braced grid shells changes from overall buckling to local buckling. Second, the nonlinear failure mode is similar to the first-order eigenvalue buckling mode and the maximal compression stress distribution. The structural integrity is weakened, and the maximal steel tube compression stress decreases with the decrease of the joint rotational stiffness. The smaller the joint rotational stiffness, the lower the utilization rate of steel strength. The results suggest that the joint stiffness of elliptic paraboloid cable-braced grid shells should not be less than 20% of the rigid joint stiffness.

Effect of irradiation on the parameters that influence quality characteristics of raw beef round eye

Feng, Xi,Jo, Cheorun,Nam, Ki Chang,Ahn, Dong U. Elsevier 2018 Innovative food science & emerging technologies Vol.45 No.-

<P><B>Abstract</B></P> <P>The objective of this study was to elucidate the relationships among lipid/protein oxidation, color changes, off-taste and off-odor in irradiated raw beef round eye. Raw beef round eye was prepared and irradiated at 0, 1.5, 3.0 and 4.5kGy using a linear accelerator. Significant increases in lipid oxidation and protein oxidation were found in irradiated raw beef round eye, while significant decreases were observed in the color values (L*-, a*-, and b*-value). The degradation of nucleotides can contribute to the taste changes (increase in sourness and decrease in umami taste) in the irradiated raw beef round eye, which was further confirmed by the electronic tongue data. The sulfur volatiles (e.g.: dimethyl disulfide) from the sulfur-containing amino acids increased significantly after irradiation, indicating these are closely related to the off-odor of irradiated beef round eye.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Lipid/protein oxidation was accelerated in raw beef round eye by irradiation. </LI> <LI> After irradiation, color values (L*-, a*-, and b*-value) in raw beef round eye decreased. </LI> <LI> The nucleotides degradation by irradiation can contribute to the taste changes. </LI> <LI> Irradiation off-odor was correlated to dimethyl disulfide and 2-butanone productions. </LI> </UL> </P>

Empirical Study of the Influence of Consumer Relationship Proneness on Customer Loyalty in Service Context

Xi Feng,Mingli Zhang,Jianhua Ye 보안공학연구지원센터 2015 International Journal of u- and e- Service, Scienc Vol.8 No.4

Consumer relationship proneness (CRP) reflects a consumer’s relatively stable and conscious tendency to engage in relationships. This study takes CRP as an important consumer individual trait and examines the influence of CRP on customer loyalty in service environment from perspective of relational benefits (i.e. confidence benefits, social benefits, special treatment benefits). Concept model is proposed to explain the influence. Then SEM (structural equation modeling) is used to analyze the data collected from online survey to test the proposed model. Empirical results show that CRP has direct influence on customer loyalty. The results also show that CRP indirectly relates to customer loyalty via its impact on perceived confidence benefits and social benefits. This study deepens the understanding about the importance of CRP and provides insights into development and implement of customer relationship management and relationship marketing for service enterprises.

Relationship between Fractional Exhaled Nitric Oxide Level and Efficacy of Inhaled Corticosteroid in Asthma-COPD Overlap Syndrome Patients with Different Disease Severity

Jia-Xi Feng,Yun Lin,Jian Lin,Su-Su He,Mei-Fang Chen,Xiao-Mai Wu,You-Zu Xu 대한의학회 2017 Journal of Korean medical science Vol.32 No.3

This study explored the relationship between the fractional exhaled nitric oxide (FeNO) level and the efficacy of inhaled corticosteroid (ICS) in asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) patients with different disease severity. A total of 127 ACOS patients with ACOS (case group) and 131 healthy people (control group) were enrolled in this study. Based on the severity of COPD, the ACOS patients were divided into: mild ACOS; moderate ACOS; severe ACOS; and extremely severe ACOS groups. We compared FeNO levels, pulmonary function parameters including percentage of forced expiratory volume in 1 second (FEV1) to predicted value (FEV1%pred), ratio of FEV1 to forced vital capacity (FEV1/FVC), inspiratory capacity to total lung capacity (IC/TLC) and residual volume to total lung capacity (RV/TLC), arterial blood gas parameters, including PH, arterial partial pressure of oxygen (PaO2) and arterial partial pressure of carbon dioxide (PaCO2), total serum immunoglobulin E (IgE), induced sputum eosinophil (EOS), plasma surfactant protein A (SP-A), plasma soluble receptor for advanced glycation end products (sRAGE), sputum myeloperoxidase (MPO), sputum neutrophil gelatinase-associated lipocalin (NGAL) and Asthma Control Test (ACT) scores, and COPD Assessment Test (CAT) scores. Compared with pre-treatment parameters, the FeNO levels, RV/TLC, PaCO2, total serum IgE, induced sputum EOS, plasma SP-A, sputum MPO, sputum NGAL, and CAT scores were significantly decreased after 6 months of ICS treatment, while FEV1%pred, FEV1/FVC, IC/TLC, PH, PaO2, plasma sRAGE, and ACT scores were significantly increased in ACOS patients with different disease severity after 6 months of ICS treatment. This finding suggests that the FeNO level may accurately predict the efficacy of ICS in the treatment of ACOS patients.

해양균류의 Tyrosinase 저해활성 검색

Li Xi-Feng 한국생약학회 2003 생약학회지 Vol.34 No.2

Effects of silver nanoparticles on neonatal testis development in mice

Zhang, Xi-Feng,Gurunathan, Sangiliyandi,Kim, Jin-Hoi Dove Medical Press 2015 International journal of nanomedicine Vol.10 No.-

<P><B>Background</B></P><P>Metal nanoparticles (MNPs) play an important role in consumer products. An increasing use of MNPs has raised concerns about potential risks for human health. Therefore, in vivo tests of MNPs are urgently required. Using mice as a model animal, the aim of the present study was designed to investigate the effect of biologically synthesized silver nanoparticles (AgNPs) on spermatogenesis in neonatal mice.</P><P><B>Methods</B></P><P>AgNPs were synthesized using <I>Bacillus funiculus</I>. The prepared nanoparticles were characterized using various analytical techniques such as UV–visible spectroscopy, X-ray diffraction, Fourier transform-infrared spectroscopy, and transmission electron microscopy. The prepared AgNPs were used to investigate testis development in neonatal mice. Institute of Cancer Research neonatal male mice were used in all experiments and were treated with different doses (0, 1, and 5 mg/kg) of AgNPs five times (interval of 3 days from postnatal day [PND] 8–21) by abdominal subcutaneous injection.</P><P><B>Results</B></P><P>The results showed that the sperm abnormalities such as quality and quantity were significantly increased by the synthesized AgNPs. The diameter of the convoluted tubules shrank significantly in mice treated with AgNPs on PND28 and PND42. The results of reverse transcription-quantitative polymerase chain reaction indicated that the <I>E1f1ay</I>, <I>Gsta4</I>, and <I>Fdx1</I> genes were up-regulated, and the <I>Amh</I>, <I>Cx43</I>, and <I>Claudin-11</I> genes were down-regulated in response to AgNPs exposure on PND28; however, these genes recovered at PND60. AgNPs had no effect on the recombination levels of chromosomes in germ cells.</P><P><B>Conclusion</B></P><P>These results demonstrated the adverse effects of AgNPs on the male reproductive tract, particularly spermatogenesis and the quality of sperm. This study suggests that the development of nanomaterials should be safer and non-toxic to the living organisms and the potential reprotoxicity of AgNPs should be investigated more carefully.</P>

Differential nanoreprotoxicity of silver nanoparticles in male somatic cells and spermatogonial stem cells

Zhang, Xi-Feng,Choi, Yun-Jung,Han, Jae Woong,Kim, Eunsu,Park, Jung Hyun,Gurunathan, Sangiliyandi,Kim, Jin-Hoi Dove Medical Press 2015 INTERNATIONAL JOURNAL OF NANOMEDICINE Vol.10 No.-

<P><B>Background</B></P><P>Silver nanoparticles (AgNPs) possess unique physical, chemical, and biological properties. AgNPs have been increasingly used as anticancer, antiangiogenic, and antibacterial agents for the treatment of bacterial infections in open wounds as well as in ointments, bandages, and wound dressings. The present study aimed to investigate the effects of two different sizes of AgNPs (10 nm and 20 nm) in male somatic Leydig (TM3) and Sertoli (TM4) cells and spermatogonial stem cells (SSCs).</P><P><B>Methods</B></P><P>Here, we demonstrate a green and simple method for the synthesis of AgNPs using <I>Bacillus cereus</I> culture supernatants. The synthesized AgNPs were characterized using ultraviolet and visible absorption spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy (TEM). The toxicity of the synthesized AgNPs was evaluated by the effects on cell viability, metabolic activity, oxidative stress, apoptosis, and expression of genes encoding steroidogenic and tight junction proteins.</P><P><B>Results</B></P><P>AgNPs inhibited the viability and proliferation of TM3 and TM4 cells in a dose- and size-dependent manner by damaging cell membranes and inducing the generation of reactive oxygen species, which in turn affected SSC growth on TM3 and TM4 as feeder cells. Small AgNPs (10 nm) were more cytotoxic than medium-sized nanoparticles (20 nm). TEM revealed the presence of AgNPs in the cell cytoplasm and nucleus, and detected mitochondrial damage and enhanced formation of autosomes and autolysosomes in the AgNP-treated cells. Flow cytometry analysis using Annexin V/propidium iodide staining showed massive cell death by apoptosis or necrosis. Real-time polymerase chain reaction and western blot analyses indicated that in TM3 and TM4 cells, AgNPs activated the p53, p38, and pErk1/2 signaling pathways and significantly downregulated the expression of genes related to testosterone synthesis (TM3) and tight junctions (TM4). Furthermore, the exposure of TM3 and TM4 cells to AgNPs inhibited proliferation and self-renewal of SSCs.</P><P><B>Conclusion</B></P><P>Our results suggest that AgNPs exhibit size-dependent nanoreprotoxicity in male somatic cells and SSCs, strongly suggesting that applications of AgNPs in commercial products must be carefully evaluated. Further studies of AgNPs-induced nanoreprotoxicity in animal models are required.</P>

Low-dose diethylhexyl phthalate exposure does not impair the expressive patterns of epigenetics-related genes and DNA methylation of breast cancer-related genes in mouse mammary glands

Shun-Feng Cheng,Ling Li,Bo Li,Jing-Cai Liu,Fang-Nong Lai,Yong Zhao,Xi-Feng Zhang,Wei Shen,Lan Li 대한독성 유전단백체 학회 2018 Molecular & cellular toxicology Vol.14 No.2

Backgrounds: Di-(2-ethylhexyl) phthalate (DEHP), as an endocrine-disrupting chemical (EDC), is widely used in plasticizer and other productions. Ubiquitous human exposure to DEHP has been proposed to be a potential risk to public health. Developmental exposure to DEHP could alter epigenetic programming and result in adult-onset disease. Methods: In this study, we investigated whether DEHP exposure to pregnant mice affected epigenetic changes as a result of increase in breast cancer incidence. Results: Our results showed that the expression of total 143 epigenetics-related genes in mammary gland cells, have no significantly altered after short time and low-dose treated with DEHP from 0.5 days post-coitum (dpc) to 3.5 dpc of pregnant mice. DNA methylation status of some neoplastic development genes, such as EGFr, Esr1, Pgr, Fos and Rassf5 also had no obvious change. Conclusion: These finding showed no impact of DEHP on the expressive patterns of epigenetics-related genes and DNA methylation of breast cancer-related genes in pregnant mouse mammary gland cells.