The tumor hypoxic microenvironment not only induces genetic and epigenetic changes in tumor cells, immature vessels formation for oxygen demand, but also compromises the efficiency of therapeutic... Show moreThe tumor hypoxic microenvironment not only induces genetic and epigenetic changes in tumor cells, immature vessels formation for oxygen demand, but also compromises the efficiency of therapeutic interventions. On the other hand, conventional therapeutic approaches which kill tumor cells or destroy tumor blood vessels to block nutrition and oxygen supply usually facilitate even harsher microenvironment. Thus, simultaneously relieving the strained response of tumor cells and blood vessels represents a promising strategy to reverse the adverse tumor hypoxic microenvironment. In the present study, an integrated amphiphilic system (RSCD) is designed based on Angiotensin II receptor blocker candesartan for siRNA delivery against the hypoxia-inducible factor-1 alpha (HIF-1α), aiming at both vascular and cellular "relaxation" to reconstruct a tumor normoxic microenvironment. Both in vitro and in vivo studies have confirmed that the hypoxia-inducible HIF-1α expression is down-regulated by 70% and vascular growth is inhibited by 60%. The "relaxation" therapy enables neovascularization with more complete and organized structures to obviously increase the oxygen level inside tumor, which results in a 50% growth inhibition. Moreover, reconstruction of tumor microenvironment enhances tumor-targeted drug delivery, and significantly improves the chemotherapeutic and photodynamic anticancer treatments. Show less
As a result of the BEPS Action Plan, the limitation on benefits rule, which is aimed at preventing treaty shopping, has become an OECDrecommended rule. The importance of the rule has been... Show moreAs a result of the BEPS Action Plan, the limitation on benefits rule, which is aimed at preventing treaty shopping, has become an OECDrecommended rule. The importance of the rule has been significantly elevated, and an increasing number of countries have adopted this rule under the impact of the BEPS project. The limitation on benefits rule has been incorporated in five of the Chinese tax treaties, and China has been actively responding to the BEPS Action Plan, therefore it is necessary to have a thorough understanding of the concept of treaty shopping and the limitation on benefits rule, especially the theoretical underpinnings and the rationales for the design of the rule. For this reason, it is hoped that thisarticle will provide useful information and analysis for policy makers to better understand and evaluate the rule, and respond to the BEPS project. Show less
Objective: To address the need for standardization of osteoarthritis (OA) phenotypes by examining the effect of heterogeneity among symptomatic (SOA) and radiographic osteoarthritis (ROA)... Show moreObjective: To address the need for standardization of osteoarthritis (OA) phenotypes by examining the effect of heterogeneity among symptomatic (SOA) and radiographic osteoarthritis (ROA) phenotypes. Methods: Descriptions of OA phenotypes of the 28 studies involved in the TREAT-OA consortium were collected. We investigated whether different OA definitions result in different association results by creating various hip OA definitions in one large population based cohort (the Rotterdam Study I (RSI)) and testing those for association with gender, age and body mass index using one-way ANOVA. For ROA, we standardized the hip-, knee- and hand ROA definitions and calculated prevalence's of ROA before and after standardization in nine cohort studies. This procedure could only be performed in cohort studies and standardization of SOA definitions was not feasible at this moment. Results: In this consortium, all studies with SOA phenotypes (knee, hip and hand) used a different definition and/or assessment of OA status. For knee-, hip- and hand ROA five, four and seven different definitions were used, respectively. Different hip ROA definitions do lead to different association results. For example, we showed in the RSI that hip OA defined as "at least definite joint space narrowing (JSN) and one definite osteophyte" was not associated with gender (P=0.22), but defined as "at least one definite osteophyte" was significantly associated with gender (P=3 x 10(-9)). Therefore, a standardization process was undertaken for ROA definitions. Before standardization a wide range of ROA prevalence's was observed in the nine cohorts studied. After standardization the range in prevalence of knee- and hip ROA was small. Conclusion: Phenotype definitions influence the prevalence of OA and association with clinical variables. ROA phenotypes within the TREAT-OA consortium were standardized to reduce heterogeneity and improve power in future genetics studies. (C) 2010 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved. Show less
Evangelou, E.; Valdes, A.M.; Kerkhof, H.J.M.; Styrkarsdottir, U.; Zhu, Y.Y.; Meulenbelt, I.; ... ; Translation Res Europe Appl 2011
Objectives Osteoarthritis (OA) is the most prevalent form of arthritis and accounts for substantial morbidity and disability, particularly in older people. It is characterised by changes in joint... Show moreObjectives Osteoarthritis (OA) is the most prevalent form of arthritis and accounts for substantial morbidity and disability, particularly in older people. It is characterised by changes in joint structure, including degeneration of the articular cartilage, and its aetiology is multifactorial with a strong postulated genetic component. Methods A meta-analysis was performed of four genome-wide association (GWA) studies of 2371 cases of knee OA and 35 909 controls in Caucasian populations. Replication of the top hits was attempted with data from 10 additional replication datasets. Results With a cumulative sample size of 6709 cases and 44 439 controls, one genome-wide significant locus was identified on chromosome 7q22 for knee OA (rs4730250, p = 9.2 x 10(-9)), thereby confirming its role as a susceptibility locus for OA. Conclusion The associated signal is located within a large (500 kb) linkage disequilibrium block that contains six genes: PRKAR2B (protein kinase, cAMP-dependent, regulatory, type II, beta), HPB1 (HMG-box transcription factor 1), COG5 (component of oligomeric golgi complex 5), GPR22 (G protein-coupled receptor 22), DUS4L (dihydrouridine synthase 4-like) and BCAP29 (B cell receptor-associated protein 29). Gene expression analyses of the (six) genes in primary cells derived from different joint tissues confirmed expression of all the genes in the joint environment. Show less
Kerkhof, H.J.; Meulenbelt, I.; Arden, N.; Cooper, C.; Doherty, M.; Felson, D.; ... ; Meurs, J. van 2010