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61.
Evelien van der Meij Giel G. Koning Patrick W. Vriens Marcel F. Peeters C. Arnoud Meijer Kim E. Kortekaas Ronald L. Dalman J. Hajo van Bockel Roeland Hanemaaijer Teake Kooistra Robert Kleemann Jan H. N. Lindeman 《PloS one》2013,8(1)
Statins are thought to reduce vascular inflammation through lipid independent mechanisms. Evaluation of such an effect in atherosclerotic disease is complicated by simultaneous effects on lipid metabolism. Abdominal aortic aneurysms (AAA) are part of the atherosclerotic spectrum of diseases. Unlike atherosclerotic occlusive disease, AAA is not lipid driven, thus allowing direct evaluation of putative anti-inflammatory effects. The anti-inflammatory potency of increasing doses (0, 20 or 40 mg/day) simvastatin or atorvastatin was evaluated in 63 patients that were at least 6 weeks on statin therapy and who underwent open AAA repair. A comprehensive analysis using immunohistochemistry, mRNA and protein analyses was applied on aortic wall samples collected during surgery. The effect of statins on AAA growth was analyzed in a separate prospective study in incorporating 142 patients. Both statins equally effectively and dose-dependently reduced aortic wall expression of NFκB regulated mediators (i.e. IL-6 (P<0.001) and MCP-1 (P<0.001)); shifted macrophage polarization towards a M2 phenotype (P<0.0003); selectively reduced macrophage-related markers such as cathepsin K and S (P<0.009 and 0.0027 respectively), and ALOX5 (P<0.0009), and reduced vascular wall NFκB activity (40 mg/day group, P<0.016). No effect was found on other cell types. Evaluation of the clinical efficacy of statins to reduce AAA progression did not indicate an effect of statins on aneurysm growth (P<0.337). Hence, in the context of AAA the clinical relevance of statins pleiotropy appears minimal. 相似文献
62.
Verónica García-Alonso Esther Titos Jose Alcaraz-Quiles Bibiana Rius Aritz Lopategi Cristina López-Vicario Per-Johan Jakobsson Salvadora Delgado Juanjo Lozano Joan Clària 《PloS one》2016,11(4)
Obesity induces white adipose tissue (WAT) dysfunction characterized by unremitting inflammation and fibrosis, impaired adaptive thermogenesis and increased lipolysis. Prostaglandins (PGs) are powerful lipid mediators that influence the homeostasis of several organs and tissues. The aim of the current study was to explore the regulatory actions of PGs in human omental WAT collected from obese patients undergoing laparoscopic bariatric surgery. In addition to adipocyte hypertrophy, obese WAT showed remarkable inflammation and total and pericellular fibrosis. In this tissue, a unique molecular signature characterized by altered expression of genes involved in inflammation, fibrosis and WAT browning was identified by microarray analysis. Targeted LC-MS/MS lipidomic analysis identified increased PGE2 levels in obese fat in the context of a remarkable COX-2 induction and in the absence of changes in the expression of terminal prostaglandin E synthases (i.e. mPGES-1, mPGES-2 and cPGES). IPA analysis established PGE2 as a common top regulator of the fibrogenic/inflammatory process present in this tissue. Exogenous addition of PGE2 significantly reduced the expression of fibrogenic genes in human WAT explants and significantly down-regulated Col1α1, Col1α2 and αSMA in differentiated 3T3 adipocytes exposed to TGF-β. In addition, PGE2 inhibited the expression of inflammatory genes (i.e. IL-6 and MCP-1) in WAT explants as well as in adipocytes challenged with LPS. PGE2 anti-inflammatory actions were confirmed by microarray analysis of human pre-adipocytes incubated with this prostanoid. Moreover, PGE2 induced expression of brown markers (UCP1 and PRDM16) in WAT and adipocytes, but not in pre-adipocytes, suggesting that PGE2 might induce the trans-differentiation of adipocytes towards beige/brite cells. Finally, PGE2 inhibited isoproterenol-induced adipocyte lipolysis. Taken together, these findings identify PGE2 as a regulator of the complex network of interactions driving uncontrolled inflammation and fibrosis and impaired adaptive thermogenesis and lipolysis in human obese visceral WAT. 相似文献
63.
Exploiting the natural diversity in adenovirus tropism for therapy and prevention of disease 总被引:15,自引:0,他引:15
Havenga MJ Lemckert AA Ophorst OJ van Meijer M Germeraad WT Grimbergen J van Den Doel MA Vogels R van Deutekom J Janson AA de Bruijn JD Uytdehaag F Quax PH Logtenberg T Mehtali M Bout A 《Journal of virology》2002,76(9):4612-4620
Since targeting of recombinant adenovirus vectors to defined cell types in vivo is a major challenge in gene therapy and vaccinology, we explored the natural diversity in human adenovirus tissue tropism. Hereto, we constructed a library of Ad5 vectors carrying fibers from other human serotypes. From this library, we identified vectors that efficiently infect human cells that are important for diverse gene therapy approaches and for induction of immunity. For several medical applications (prenatal diagnosis, artificial bone, vaccination, and cardiovascular disease), we demonstrate the applicability of these novel vectors. In addition, screening cell types derived from different species revealed that cellular receptors for human subgroup B adenoviruses are not conserved between rodents and primates. These results provide a rationale for utilizing elements of human adenovirus serotypes to generate chimeric vectors that improve our knowledge concerning adenovirus biology and widen the therapeutic window for vaccination and many different gene transfer applications. 相似文献
64.
Reduced expression of CD62L can identify tumor-specific T cells in lymph nodes draining murine tumors. Here, we examined whether this strategy could isolate tumor-specific T cells from vaccinated patients. Tumor vaccine-draining lymph node (TVDLN) T cells of seven patients were separated into populations with reduced (CD62LLow) or high levels of CD62L (CD62LHigh). Effector T cells generated from CD62LLow cells maintained or enriched the autologous tumor-specific type 1 cytokine response compared to unseparated TVDLN T cells in four of four patients showing tumor-specific cytokine secretion. Interestingly, effector T cells generated from CD62LLow or CD62LHigh TVDLN were polarized towards a dominant type 1 or type 2 cytokine profile, respectively. For CD62LLow T cells the type 1 cytokine profile appeared determined prior to culture. Since a tumor-specific type 1 cytokine profile appears critical for mediating anti-tumor activity in vivo, this approach might be used to isolate T cells for adoptive immunotherapy. 相似文献
65.
Zuurbier CJ Eerbeek O Meijer AJ 《American journal of physiology. Heart and circulatory physiology》2005,289(1):H496-H499
Association of hexokinase (HK) with mitochondria preserves mitochondrial integrity and is an important mechanism by which cancer cells are protected against hypoxic conditions. Maintenance of mitochondrial integrity also figures prominently as a major characteristic of many cardioprotective manipulations. In this study, we provide evidence that cardioprotective interventions may promote HK redistribution from the cytosol to the mitochondria in the heart. Isolated Langendorff-perfused rat hearts (n = 6/group) were subjected to normoxic perfusion (control, Con), three 5-min ischemia-reperfusion periods (ischemic preconditioning, IPC), 1 U/l insulin (Ins), or 1 microM morphine (Mor). Hearts were immediately homogenized and centrifuged to obtain whole cell, cytosolic, and mitochondrial fractions. HK, lactate dehydrogenase (LDH), and citrate synthase (CS) enzyme activities were determined. No change in LDH or CS present in the cytosol fraction relative to whole cell activity was observed with any of the cardioprotective interventions. By contrast, HK present in the cytosol fraction relative to whole cell activity decreased significantly (P < 0.05) with all cardioprotective interventions, from 0.58 +/- 0.03 (Con) to 0.46 +/- 0.04 (IPC), 0.41 +/- 0.01 (Ins), and 0.45 +/- 0.02 (Mor). In addition, HK relative to CS activity in the mitochondrial fraction increased significantly with cardioprotection, from 0.15 +/- 0.001 (Con) to 0.21 +/- 0.002 (IPC), 0.18 +/- 0.003 (Ins), and 0.21 +/- 0.005 (Mor). Our novel data suggest that well-known cardioprotective interventions share a common end-effector mechanism of cytosolic HK translocation. Association of HK with mitochondria may promote inhibition of the mitochondrial permeability transition pore and thereby reduce cell death and apoptosis. 相似文献
66.
67.
Bloem E Meems H van den Biggelaar M van der Zwaan C Mertens K Meijer AB 《The Journal of biological chemistry》2012,287(8):5775-5783
The A2 domain rapidly dissociates from activated factor VIII (FVIIIa) resulting in a dampening of the activity of the activated factor X-generating complex. The amino acid residues that affect A2 domain dissociation are therefore critical for FVIII cofactor function. We have now employed chemical footprinting in conjunction with mass spectrometry to identify lysine residues that contribute to the stability of activated FVIII. We hypothesized that lysine residues, which are buried in FVIII and surface-exposed in dissociated activated FVIII (dis-FVIIIa), may contribute to interdomain interactions. Mass spectrometry analysis revealed that residues Lys(1967) and Lys(1968) of region Thr(1964)-Tyr(1971) are buried in FVIII and exposed to the surface in dis-FVIIIa. This result, combined with the observation that the FVIII variant K1967I is associated with hemophilia A, suggests that these residues contribute to the stability of activated FVIII. Kinetic analysis revealed that the FVIII variants K1967A and K1967I exhibit an almost normal cofactor activity. However, these variants also showed an increased loss in cofactor activity over time compared with that of FVIII WT. Remarkably, the cofactor activity of a K1968A variant was enhanced and sustained for a prolonged time relative to that of FVIII WT. Surface plasmon resonance analysis demonstrated that A2 domain dissociation from activated FVIII was reduced for K1968A and enhanced for K1967A. In conclusion, mass spectrometry analysis combined with site-directed mutagenesis studies revealed that the lysine couple Lys(1967)-Lys(1968) within region Thr(1964)-Tyr(1971) has an opposite contribution to the stability of FVIIIa. 相似文献
68.
Jinkook Lee Jenny Wilkens Erik Meijer T. V. Sekher David E. Bloom Peifeng Hu 《PLoS medicine》2022,19(1)
BackgroundHypertension is the most important cardiovascular risk factor in India, and representative studies of middle-aged and older Indian adults have been lacking. Our objectives were to estimate the proportions of hypertensive adults who had been diagnosed, took antihypertensive medication, and achieved control in the middle-aged and older Indian population and to investigate the association between access to healthcare and hypertension management.Methods and findingsWe designed a nationally representative cohort study of the middle-aged and older Indian population, the Longitudinal Aging Study in India (LASI), and analyzed data from the 2017–2019 baseline wave (N = 72,262) and the 2010 pilot wave (N = 1,683). Hypertension was defined as self-reported physician diagnosis or elevated blood pressure (BP) on measurement, defined as systolic BP ≥ 140 mm Hg or diastolic BP ≥ 90 mm Hg. Among hypertensive individuals, awareness, treatment, and control were defined based on self-reports of having been diagnosed, taking antihypertensive medication, and not having elevated BP, respectively. The estimated prevalence of hypertension for the Indian population aged 45 years and older was 45.9% (95% CI 45.4%–46.5%). Among hypertensive individuals, 55.7% (95% CI 54.9%–56.5%) had been diagnosed, 38.9% (95% CI 38.1%–39.6%) took antihypertensive medication, and 31.7% (95% CI 31.0%–32.4%) achieved BP control. In multivariable logistic regression models, access to public healthcare was a key predictor of hypertension treatment (odds ratio [OR] = 1.35, 95% CI 1.14–1.60, p = 0.001), especially in the most economically disadvantaged group (OR of the interaction for middle economic status = 0.76, 95% CI 0.61–0.94, p = 0.013; OR of the interaction for high economic status = 0.84, 95% CI 0.68–1.05, p = 0.124). Having health insurance was not associated with improved hypertension awareness among those with low economic status (OR = 0.96, 95% CI 0.86–1.07, p = 0.437) and those with middle economic status (OR of the interaction = 1.15, 95% CI 1.00–1.33, p = 0.051), but it was among those with high economic status (OR of the interaction = 1.28, 95% CI 1.10–1.48, p = 0.001). Comparing hypertension awareness, treatment, and control rates in the 4 pilot states, we found statistically significant (p < 0.001) improvement in hypertension management from 2010 to 2017–2019. The limitations of this study include the pilot sample being relatively small and that it recruited from only 4 states.ConclusionsAlthough considerable variations in hypertension diagnosis, treatment, and control exist across different sociodemographic groups and geographic areas, reducing uncontrolled hypertension remains a public health priority in India. Access to healthcare is closely tied to both hypertension diagnosis and treatment.Jinkook Lee and colleagues investigate hypertension management and its association with healthcare access in middle-aged and older adults in India. 相似文献
69.
Emmanuel Deau Yvonnick Loidreau Pascal Marchand Marie-Renée Nourrisson Nadège Loaëc Laurent Meijer Vincent Levacher Thierry Besson 《Bioorganic & medicinal chemistry letters》2013,23(24):6784-6788
The efficient synthesis of 7-substituted pyrido[2′,3′:4,5]furo[3,2-d]pyrimidin-4-amines and their N-aryl analogues is described. 3,5-Dibromopyridine was converted into 3-amino-6-bromofuro[3,2-b]pyridine-2-carbonitrile intermediate which was formylated with DMFDMA. Functionalization at position 7 of the tricyclic scaffold was accomplished, before or after cyclisation step, by palladium-catalyzed Suzuki–Miyaura cross-coupling while the pyrimidin-4-amines and N-aryl counterparts were synthesized by microwave-assisted formamide degradation and Dimroth rearrangement, respectively. The final products were evaluated for their potent inhibition of a series of five Ser/Thr kinases (CDK5/p25, CK1δ/ε, CLK1, DYRK1A, GSK3α/β). Compound 35 showed the best inhibitory activity with an IC50 value of 49 nM and proved to be specific to CLK1 among the panel of tested kinases. 相似文献
70.
Hermes HF Sonke T Peters PJ van Balken JA Kamphuis J Dijkhuizen L Meijer EM 《Applied and environmental microbiology》1993,59(12):4330-4334
An l-aminopeptidase of Pseudomonas putida, used in an industrial process for the hydrolysis of d,l-amino acid amide racemates, was purified to homogeneity. The highly l-enantioselective enzyme resembled thiol reagent-sensitive alkaline serine proteinases and was strongly activated by divalent cations. It possessed a high substrate specificity for dipeptides and alpha-H amino acid amides, e.g., l-phenylglycine amide. 相似文献