Homoisoflavanones from Polygonatum odoratum Rhizomes Inhibit Advanced Glycation End Product Formation

Wei Dong,Hai Bo Shi,Heng Ma,Yan Bo Miao,Tong Jun Liu,Wei Wang 대한약학회 2010 Archives of Pharmacal Research Vol.33 No.5

Protein glycation inhibitors from Polygonatum odoratum rhizomes were investigated using a bioassay-guided procedure to characterize active compounds for preventing and treating diabetic complications. The EtOH extract and soluble fractions were evaluated using an in vivo model of renal advanced glycation end-product (AGE) accumulation in streptozotocin-induced diabetic rats and an in vitro bovine serum albumin-glucose assay. Three homoisoflavanones 3-(4’-hydroxybenzyl)-5,7-dihydroxy-6-methyl-8-methoxychroman-4-one (1), 3-(4’-hydroxybenzyl)-5,7-dihydroxy-6,8-dimethylchroman-4-one (2), and 3-(4’-methoxybenzyl)-5,7-dihydroxy-6-methyl-8-methoxychroman-4-one (3), isolated from the active CHCl3-soluble fraction of the EtOH extract, were subjected to in vitro bioassays to evaluate their inhibitory activities against AGE formation. All the isolates inhibited AGE formation more effectively than the positive control, aminoguanidine. These results indicate that pending further study these compounds could be used as novel natural product drug for mitigating diabetic complications.

Enhanced electrical conductivity and electromagnetic shielding efficiency of epoxy resin using graphene nanoplatelets

Wei Dong,Miao Zhao,Fan-Long Jin,박수진 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.7

Graphene nanoplatelets (GNPs) employed as conductive fillers were added to an epoxy matrix, diglycidyletherof bisphenol-A (DGEBA), to enhance the electrical conductivity and electromagnetic shielding efficiency ofDGEBA. In addition, we investigated the influence of GNP fraction on the thermal properties, flexural strength, impactstrength, electrical conductivity, electromagnetic shielding efficiency, and morphology of DGEBA/GNP nanocomposites. The electrical properties indicated that the electrical conductivity of DGEBA/GNP nanocomposites consisting ofhigher than 7.5 wt% GNPs was significantly improved compared to that of pristine DGEBA. The electromagneticshielding efficiency of the nanocomposite showed a maximum value of 3.87 dB at 10 wt% GNPs, which is 287% higherthan that of pristine DGEBA. An analysis of the fracture surfaces of the nanocomposites showed a rough morphologywith numerous micro-cracks. In addition, the GNPs in the DGEBA matrix were stacked and formed a continuousconductive path at high GNP contents.

Variation of sexual dimorphism and asymmetry in disease expression of inflammatory arthritis among laboratory mouse models with different genomic backgrounds

Wei Dong,Cheng Tian,Z. Galvin Li,David Brand,Yanhong Cao,Xiaoyun Liu,Jiamin Ma,Andy Chai,LindaK.myers,Jian Yan,Karen Hasty,John Stuart,Yan Jiao,Weikuan Gu,Xiaojun Cai 한국실험동물학회 2023 Laboratory Animal Research Vol.39 No.4

Sex difference has shown in the arthritis diseases in human population and animal models. We investigate how the sex and symmetry vary among mouse models with different genomic backgrounds. Disease data of sex and limbs accumulated in the past more than two decades from four unique populations of murine arthritis models were analyzed. They are (1) interleukin-1 receptor antagonist (IL-1ra) deficient mice under Balb/c background (Balb/c KO); (2) Mice with collagen II induced arthritis under DBA/1 background; (3) Mice with collagen II induced arthritis under C57BL/6 (B6) background and (4) A F2 generation population created by Balb/c KO X DBA/1 KO. Our data shows that there is a great variation in sexual dimorphism for arthritis incidence and severity of arthritis in mice harboring specific genetic modifications. For a F2 population, the incidence of arthritis was 57.1% in female mice and 75.6% in male mice. There was a difference in severity related to sex in two populations: B6.DR1/ B6.DR4 (P < 0.001) and F2 (P = 0.023) There was no difference Balb/c parental strain or in collagen-induced arthritis (CIA) in DBA/1 mice. Among these populations, the right hindlimbs are significantly higher than the scores for the left hindlimbs in males (P < 0.05). However, when examining disease expression using the collagen induced arthritis model with DBA/1 mice, sex-dimorphism did not reach statistical significance, while left hindlimbs showed a tendency toward greater disease expression over the right. Sexual dimorphism in disease expression in mouse models is strain and genomic background dependent. It sets an alarm that potential variation in sexual dimorphism among different racial and ethnic groups in human populations may exist. It is important to not only include both sexes and but also pay attention to possible variations caused by disease expression and response to treatment in all the studies of arthritis in animal models and human populations.

A Rerouting-Controlled ISL Handover Protocol For LEO Satellite Networks

( Wei Dong ),( Junfeng Wang ),( Minhuan Huang ),( Jian Tang ),( Hongxia Zhou ) 한국인터넷정보학회 2012 KSII Transactions on Internet and Information Syst Vol.6 No.10

In this paper, a rerouting-controlled ISL (Inter-Satellite link) handover protocol for LEO satellite networks (RCIHP) is proposed. Through topological dynamics and periodic characterization of LEO satellite constellation, the protocol firstly derives the ISL related information such as the moments of ISL handovers and the intervals during which ISLs are closed and cannot be used to forward packet. The information, combined with satellite link load status, is then been utilized during packet forwarding process. The protocol makes a forwarding decision on a per packet basis and only routes packets to living and non-congested satellite links. Thus RCIHP avoids periodic rerouting that occurs in traditional routing protocols and makes it totally unnecessary. Simulation studies show that RCIHP has a good performance in terms of packet dropped possibility and end-to-end delay.

ATCS: An Adaptive TCP Coding Scheme for Satellite IP Networks

( Wei Dong ),( Junfeng Wang ),( Minhuan Huang ),( Jian Tang ),( Hongxia Zhou ) 한국인터넷정보학회 2011 KSII Transactions on Internet and Information Syst Vol.5 No.5

In this paper we propose ATCS, a practical TCP protocol coding scheme based on network coding for satellite IP networks. The proposal is specially designed to enhance TCP performance over satellite networks. In our scheme, the source introduces a degree of redundancy and transmits a random linear combination of TCP packets. Since the redundant packets are utilized to mask packet loss over satellite links, the degree of redundancy is determined by the link error rates. Through a simple and effective method, ATCS estimates link error rates in real time and then dynamically adjusts the redundant factor. Consequently, ATCS is adaptable to a wide range of link error rates by coding TCP segments with a flexible redundancy factor. Furthermore, the scheme is compatible with traditional TCP variants. Simulation results indicate that the proposal improves TCP performance considerably.

Frequency Tracking of Power Grid based on Phase Difference and UKF

Wei Dong,Wei Dong,Shichao Jiang 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.12

For frequency tracking problem of non-stationary signals in power grid, we propose a unscented Kalman filter (UKF) and the weighted phase difference smoothing algorithm. It improved poor initial conditions sensitive situations of robustness UKF. In order to improve the accuracy of the algorithm, real-time and noise immunity, a suboptimal multiple fading factor and weighted smoothing method is added to improve UKF for frequency tracking of power signals. At last, The simulation results are given. It shows that this method has better accurate, real-time tracking of various frequency power signal and its performance is superior to similar documents tracking algorithm.

Fracture toughness improvement of epoxy resins with short carbon fibers

Wei Dong,Fan-Long Jin,박수진,Heng-Chang Liu 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.4

This study examined the thermal stability and fracture toughness of diglycidylether of bisphenol-A (DGEBA)/short carbon fiber (SCF) composites using several techniques. The thermal stability of the DGEBA/SCF composites was similar to that of neat epoxy resin. The fracture toughness of the composites was significantly improved relative to the neat resin. The SEM micrographs indicated that a relatively rough surface with shear deformation and tortuous cracks was formed, thereby preventing deformation and crack propagation and inducing higher fracture toughness in the DGEBA/SCF composites.

ENHANCEMENT OF LIPID EXTRACTION BY MIXTRURE OF ETHYL ACETATE AND EHANOL FROM MICROALGAE VIA DEEP EUTECTIC SOLVENTS PRETREATMENT

Weidong LU,Zhongming WANG,Ying PAN,Zhenhong Yuan 한국신재생에너지학회 2015 AFORE Vol.2015 No.11

Surface interactions between two of the main periodontal pathogens: Porphyromonas gingivalis and Tannerella forsythia

Weidong Zhu,이석우 대한치주과학회 2016 Journal of Periodontal & Implant Science Vol.46 No.1

Purpose: Porphyromonas gingivalis and Tannerella forsythia have been implicated as the major etiologic agents of periodontal disease. These two bacteria are frequently isolated together from the periodontal lesion, and it has been suggested that their interaction may increase each one’s virulence potential. The purpose of this study was to identify proteins on the surface of these organisms that are involved in interbacterial binding. Methods: Biotin labeling of surface proteins of P. gingivalis and T. forsythia and liquid chromatography–tandem mass spectrometry (LC-MS/MS) analysis was performed to identify surface proteins involved in the coaggregating activity between P. gingivalis and T. forsythia. Results: It was found that three major T. forsythia proteins sized 161, 100, and 62 kDa were involved in binding to P. gingivalis , and P. gingivalis proteins sized 35, 32, and 26 kDa were involved in binding to T. forsythia cells. Conclusions: LC-MS/MS analysis identified one T. forsythia surface protein (TonB-linked outer membrane protein) involved in interbacterial binding to P. gingivalis. However, the nature of other T. forsythia and P. gingivalis surface proteins identified by biotin labeling could not be determined. Further analysis of these proteins will help elucidate the molecular mechanisms that mediate coaggregation between P. gingivalis and T. forsythia.

Secretion of Truncated Recombinant Rabies Virus Glycoprotein with Preserved Antigenic Properties Using a Co-Expression System in Hansenula polymorpha

Weidong Qian,Frank Aguilar,Ting Wang,Bingsheng Qiu 한국미생물학회 2013 The journal of microbiology Vol.51 No.2

Rabies virus infection remains a serious public health threat in the developing world, where cost-concerns make widescale public health interventions impractical. The development of novel and inexpensive ELISA diagnostic antigens is critical in early detection and prevention of complications. The transmembrane glycoprotein (G) of rabies virus (RV)contains an external domain capable of inducing the synthesis of anti-rabies, virus-neutralizing antibodies, in infected or immunized hosts. In our study, the external G domain was synthesized and fused in-frame with a polyhistidine-tag coding sequence present in the expression plasmid. Soluble truncated recombinant G was secreted in Hansenula polymorpha (H. polymorpha) using H. polymorpha-derived calnexin (HpCNE1) overproduction and found to be correctly N-glycosylated. The truncated recombinant G was purified from cell culture supernatant by Ni-agarose affinity chromatography and when compared with the full-length glycoprotein,found to be similarly immunogenic in vaccinated rabbits. These results subsequently led us to explore the potential of truncated recombinant G as a diagnostic antigen in ELISA. Our results show that the truncated recombinant G can detect antibodies directed to both whole virion and native glycoprotein. More sophisticated applications of truncated recombinant G would profit from the correctly N-glycosylated and soluble monomer.