Erratum to: Experimental Study and Numerical Analysis on Mechanical Behavior of T-shape Stiffened Orthotropic Steelconcrete Composite Bridge Decks

Xu Jiang,Qing-Tian Su,Xu Han,Changyu Shao,Liang Chen 한국강구조학회 2017 International Journal of Steel Structures Vol.17 No.4

Induction of Phase I, II and III Drug Metabolism/Transport by Xenobiotics

Xu Chang Jiang,Li Christina YongTao,Kong AhNg Tony The Pharmaceutical Society of Korea 2005 Archives of Pharmacal Research Vol.28 No.3

Drug metabolizing enzymes (DMEs) play central roles in the metabolism, elimination and detoxification of xenobiotics and drugs introduced into the human body. Most of the tissues and organs in our body are well equipped with diverse and various DMEs including phase I, phase II metabolizing enzymes and phase III transporters, which are present in abundance either at the basal unstimulated level, and/or are inducible at elevated level after exposure to xenobiotics. Recently, many important advances have been made in the mechanisms that regulate the expression of these drug metabolism genes. Various nuclear receptors including the aryl hydrocarbon receptor (AhR), orphan nuclear receptors, and nuclear factor-erythoroid 2 p45-related factor 2 (Nrf2) have been shown to be the key mediators of drug-induced changes in phase I, phase II metabolizing enzymes as well as phase III transporters involved in efflux mechanisms. For instance, the expression of CYP1 genes can be induced by AhR, which dimerizes with the AhR nuclear translocator (Arnt) , in response to many polycyclic aromatic hydrocarbon (PAHs). Similarly, the steroid family of orphan nuclear receptors, the constitutive androstane receptor (CAR) and pregnane X receptor (PXR), both heterodimerize with the ret-inoid X receptor (RXR), are shown to transcriptionally activate the promoters of CYP2B and CYP3A gene expression by xenobiotics such as phenobarbital-like compounds (CAR) and dexamethasone and rifampin-type of agents (PXR). The peroxisome proliferator activated receptor (PPAR), which is one of the first characterized members of the nuclear hormone receptor, also dimerizes with RXR and has been shown to be activated by lipid lowering agent fib rate-type of compounds leading to transcriptional activation of the promoters on CYP4A gene. CYP7A was recognized as the first target gene of the liver X receptor (LXR), in which the elimination of cholesterol depends on CYP7A. Farnesoid X receptor (FXR) was identified as a bile acid receptor, and its activation results in the inhibition of hepatic acid biosynthesis and increased transport of bile acids from intestinal lumen to the liver, and CYP7A is one of its target genes. The transcriptional activation by these receptors upon binding to the promoters located at the 5-flanking region of these GYP genes generally leads to the induction of their mRNA gene expression. The physiological and the pharmacological implications of common partner of RXR for CAR, PXR, PPAR, LXR and FXR receptors largely remain unknown and are under intense investigations. For the phase II DMEs, phase II gene inducers such as the phenolic compounds butylated hydroxyanisol (BHA), tert-butylhydroquinone (tBHQ), green tea polyphenol (GTP), (-)-epigallocatechin-3-gallate (EGCG) and the isothiocyanates (PEITC, sul­foraphane) generally appear to be electrophiles. They generally possess electrophilic-medi­ated stress response, resulting in the activation of bZIP transcription factors Nrf2 which dimerizes with Mafs and binds to the antioxidant/electrophile response element (ARE/EpRE) promoter, which is located in many phase II DMEs as well as many cellular defensive enzymes such as heme oxygenase-1 (HO-1), with the subsequent induction of the expression of these genes. Phase III transporters, for example, P-glycoprotein (P-gp), multidrug resistance-associated proteins (MRPs), and organic anion transporting polypeptide 2 (OATP2) are expressed in many tissues such as the liver, intestine, kidney, and brain, and play crucial roles in drug absorption, distribution, and excretion. The orphan nuclear receptors PXR and GAR have been shown to be involved in the regulation of these transporters. Along with phase I and phase II enzyme induction, pretreatment with several kinds of inducers has been shown to alter the expression of phase III transporters, and alter the excretion of xenobiotics, which implies that phase III transporters may also be similarly regulated in a coord

Cellular phenotypes as inflammatory mediators in Parkinson’s disease: Interventional targets and role of natural products

Jiang, Xu,Ganesan, Palanivel,Rengarajan, Thamaraiselvan,Choi, Dong-Kug,Arulselvan, Palanisamy Elsevier 2018 BIOMEDICINE AND PHARMACOTHERAPY Vol.106 No.-

<P><B>Abstract</B></P> <P>Pathogenesis of Parkinson’s disease (PD) is undoubtedly a multifactorial phenomenon, with diverse etiological agents. Pro-inflammatory mediators act as a skew that directs disease progression during neurodegenerative diseases. Understanding the dynamics of inflammation and inflammatory mediators in preventing or reducing disease progression has recently gained much attention. Inflammatory neuro-degeneration is regulated via cytokines, chemokines, lipid mediators and immune cell subsets; however, individual cellular phenotypes in the Central Nervous System (CNS) acts in diverse ways whose persistent activation leads to unresolving inflammation often causing unfavorable outcomes in neurodegenerative disease like PD. Specifically, activation of cellular phenotypes like astrocytes, microglia, activation of peripheral immune cells requires different activation signals and agents like (cytokines, misfolded protein aggregates, infectious agents, pesticides like organophosphates, etc.,). However, what is unknown is how the different cellular phenotypes respond uniquely and the role of the factors they secrete alters the signal cascades in the complex neuron-microglial connections in the CNS. Hence, understanding the role of cellular phenotypes and the inflammatory mediators, the cross talk among the signals and their receptors can help us to identify the potential therapeutic target using natural products. In this review we have tried to put together the role of cellular phenotypes as a skew that favors PD progression and we have also discussed how the lack of experimental approaches and challenges that affects understanding the cellular targets that can be used against natural derivatives in alleviating PD pathophysiology. Together, this review will provide the better insights into the role of cellular phenotypes of neuroinflammation, inflammatory mediators and the orchestrating factors of inflammation and how they can be targeted in a more specific way that can be used in the clinical management of PD.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Distinct cellular Phenotypes acts uniquely in the pathogenesis of PD. </LI> <LI> Inflammation can be cause and consequence of PD pathogenesis. </LI> <LI> Flavonoids regulate multiple modulators of inflammation in mitigating PD pathology. </LI> <LI> Diverse intrinsic/extrinsic mediators converge together in glial activation in exacerbating PD pathology. </LI> </UL> </P>

The application of new technologies on Panax and Ganoderma

Jiang Xu,Shilin Chen 한국약용작물학회 2012 한국약용작물학회 학술대회논문집 Vol.2012 No.2

Stochastic Revenue and Cost Model for Determining a BOT Concession Period under Multiple Project Constraints

Xu, Jiang-wei,Moon, Sungwoo American Society of Civil Engineers 2014 Journal of management in engineering Vol.30 No.3

The concession period is an important issue in the contractual arrangement of build-operate-transfer (BOT) projects, such as highways, bridges, and tunnels. In determining the concession period, it is predominantly the toll revenue and construction costs that affect how long the concessionaire needs to be in operation after the completion of the project. This paper presents a stochastic revenue and cost model to determine a concession period under multiple constraints in planning a BOT infrastructure project. In the study, the stochastic process is converted into an equivalent discrete form, and its parameters are estimated using historical data. Based on the process, a principle-agent problem is addressed as a solution to the conflict between the owner and the concessionaire. This methodology incorporates these stakeholders' interests in terms of (1)incentive constraints, and (2)participation constraints. In a case study, a numerical simulation is carried out to assess the risk of toll revenue and construction costs when applied in practice and to demonstrate the applicability of the stochastic revenue and cost model.

Fine Mapping of Pa-6 Gene for Purple Apiculus in Rice

Xu Liu,Xu Sun,Wenying Wang,Hanfeng Ding,Wei Liu,Guangxian Li,Mingsong Jiang,Changxiang Zhu,Fangyin Yao 한국식물학회 2012 Journal of Plant Biology Vol.55 No.3

Purple apiculus is one of the important agronomic traits of rice. Single-segment substitution line (SSSL) W23-07-6-02-14 in the genetic background of an elite rice variety Huajingxian74 (HJX74) with the substituted interval of RM225-RM217-RM253 on the chromosome 6 was found to have purple apiculus (Pa). To map the gene governing Pa,W23-07-6-02-14 was crossed with the recipient HJX74 to develop an F2 secondary segregation population. The ratio of purple apiculus to green apiculus showed a good fit to 3:1 ratio,indicating that Pa was controlled by a major dominant gene. The gene locus for Pa was tentatively designated as Pa-6. Using 430 individuals from the F2 segregation population, the Pa-6 locus was mapped between two SSR markers RM19556and RM19561 with genetic distances of 0.2 and 0.3 cM,respectively. For fine mapping of the Pa-6 gene, a large F2:3segregation population of 3890 individuals was developed from F2 heterzygous plants in the RM19556-RM19561 region. Recombinant analyses further mapped the Pa-6 gene locus to an interval of 41.7-kb bounded L02 and RM19561. Sequence analysis of this 41.7-kb region revealed that it contains eleven open reading frames (ORFs), of which, ORF5 is classified as the one that is associated with the C (chromogen for anthocyanin) gene, it was presumed to be the candidate gene for Pa. This result provided a foundation of map-based cloning and function analysis of the Pa-6 gene.

Study on Intrusion Detection Policy for Wireless Sensor Networks

Jiang Xu,Jin Wang,Shengdong Xie,Wenliang Chen,Jeong-Uk Kim 보안공학연구지원센터 2013 International Journal of Security and Its Applicat Vol.7 No.1

Determination of the Optimal Concession Period for BOT Contract Projects Based on a Discrete Stochastic Process Model

Xu, Jiang-Wei,Jiang, Li,Moon, Sungwoo American Society of Civil Engineers 2017 Journal of construction engineering and management Vol.143 No.4

<P>The concession period is one of the most important issues in the contractual arrangement of build-operate-transfer (BOT) projects. When planning a BOT project, the government should aim for a trade-off between the concerned government's satisfaction and the private concessionaire's profit. The objective of this paper is to present a discrete stochastic process model to obtain an optimal concession period considering the trade-off. The process model is developed for a highway project by analyzing the actual traffic data. The net present value (NPV) is calculated for use as a constraint condition that indicates the boundary of risk preference in a utility function. Using a utility function, this paper estimates the duration of concession periods at which the government can both attract investments from private concessionaires and satisfy public opinion. A numerical simulation is applied to demonstrate the applicability of the methodology presented. The result of the simulation shows that the discrete stochastic process model contributes to a better understanding of trade-offs in determining the optimal concession period.</P>

Behavior and molecular physiology of nurses of worker and queen larvae in honey bees (Apis mellifera)

Xu Jiang He,Liu Qing Tian,AndrewB. Barron,Cui Guan,Hao Liu,Xiaobo Wu,Zhi Jiang Zeng 한국응용곤충학회 2014 Journal of Asia-Pacific Entomology Vol.17 No.4

In a honey bee colony, worker bees rear a newqueen by providing herwith a larger cell inwhich to develop and alarge amount of richer food (royal jelly). Royal jelly and worker jelly (fed to developing worker larvae) differ interms of sugar, vitamin, protein and nucleotide composition. Here we examined whether workers attendingqueen andworker larvae are separate specialized sub-castes of the nurse bees.We collected nurse bees attendingqueen larvae (AQL) and worker larvae (AWL) and compared gene expression profiles of hypopharyngeal glandtissues, using Solexa/Illumina digital gene expression tag profiling (DGE). Significant differences in gene expressionwere found that included a disproportionate number of genes involved in glandular secretion and royal jellysynthesis. However behavioral observations showed that thesewere not two entirely distinct populations. Nurseworkers were observed attending both worker larvae and queen larvae, and there was no evidence of a specializedgroup of workers that preferentially or exclusively attended developing queens. Nevertheless, AQL attendedlarvaemore frequently compared toAWL, suggesting that nurses sampled attending queen larvaemay have beenthe most active nurses. This study serves as another example of the relationship between differences in gene expressionand behavioral specialisation in honey bees.

XFEM-based Fatigue Crack Propagation Analysis on Key Welded Connections of Orthotropic Steel Bridge Deck

Xu Jiang,Kai Sun,Xuhong Qiang,Dan Li,Qiwei Zhang 한국강구조학회 2023 International Journal of Steel Structures Vol.23 No.2

Orthotropic steel decks(OSD’s) are prone to fatigue cracking under cyclic loads, especially for rib-to-deck welded connection and rib-to-crossbeam welded connection. To reveal fracturing behaviors of these fatigue-prone sites, a multi-scale model of OSD’s specimen is established, including segmental shell-element part and local solid-element configuration. Based on the extended finite element method(XFEM), propagation analysis was carried out in this research. The analysis of stress intensity factor (SIF) shows that the crack at the weld root or weld toe of the rib-to-deck welded connection is a mixed-crack with modes I, II and III, where mode I plays a leading role. Besides, the maximum SIF KI of the crack at the weld toe is slightly larger than that at the weld root. For rib-to-crossbeam welded connection, the maximum SIF KI at the weld toe of the U-rib is greater than that at the weld toe of the crossbeam. The analysis of crack propagation shows that the crack growth rate at the weld toe is faster than that at the weld root with the same initial crack size and loading conditions. Similarly, for rib-to-crossbeam welded connection, the crack propagation at the weld toe of U-rib performs faster than that at the weld toe of crossbeam.