Maastricht University

About: Maastricht University is a education organization based out in Maastricht, Limburg, Netherlands. It is known for research contribution in the topics: Population & Health care. The organization has 19263 authors who have published 53291 publications receiving 2266866 citations. The organization is also known as: Universiteit Maastricht & UM.

Myeloperoxidase: Molecular Mechanisms of Action and Their Relevance to Human Health and Disease

Abstract: Myeloperoxidase (MPO) is a heme-containing peroxidase abundantly expressed in neutrophils and to a lesser extent in monocytes. Enzymatically active MPO, together with hydrogen peroxide and chloride, produces the powerful oxidant hypochlorous acid and is a key contributor to the oxygen-dependent microbicidal activity of phagocytes. In addition, excessive generation of MPO-derived oxidants has been linked to tissue damage in many diseases, especially those characterized by acute or chronic inflammation. It has become increasingly clear that MPO exerts effects that are beyond its oxidative properties. These properties of MPO are, in many cases, independent of its catalytic activity and affect various processes involved in cell signaling and cell-cell interactions and are, as such, capable of modulating inflammatory responses. Given these diverse effects, an increased interest has emerged in the role of MPO and its downstream products in a wide range of inflammatory diseases. In this article, our knowledge pertaining to the biologic role of MPO and its downstream effects and mechanisms of action in health and disease is reviewed and discussed.

In vivo expression of Toll-like receptor 2 and 4 by renal epithelial cells: IFN-gamma and TNF-alpha mediated up-regulation during inflammation.

Abstract: The reported requirement of functional Toll-like receptor (TLR)4 for resistance to Gram-negative pyelonephritis prompted us to localize the expression of TLR2 and TLR4 mRNA in the kidney at the cellular level by in situ hybridization The majority of the constitutive TLR2 and TLR4 mRNA expression was found to be strategically located in the renal epithelial cells Assuming that the TLR mRNA expression is representative of apical protein expression, this suggests that these cells are able to detect and react with bacteria present in the lumen of the tubules To gain insight in the regulation of TLR expression during inflammation, we used a model for renal inflammation Renal inflammation evoked by ischemia markedly enhanced synthesis of TLR2 and TLR4 mRNA in the distal tubular epithelium, the thin limb of Henle’s loop, and collecting ducts The increased renal TLR4 mRNA expression was associated with significant elevation of renal TLR4 protein expression as evaluated by Western blotting Using RT-PCR, the enhanced TLR2 and TLR4 mRNA expression was shown to be completely dependent on the action of IFN-γ and TNF-α These results indicate a potential mechanism of increased immunosurveillance during inflammation at the site in which ascending bacteria enter the kidney tissue, ie, the collecting ducts and the distal part of the nephron

A network approach to psychopathology: New insights into clinical longitudinal data

Abstract: In the network approach to psychopathology, disorders are conceptualized as networks of mutually interacting symptoms (e.g., depressed mood) and transdiagnostic factors (e.g., rumination). This suggests that it is necessary to study how symptoms dynamically interact over time in a network architecture. In the present paper, we show how such an architecture can be constructed on the basis of time-series data obtained through Experience Sampling Methodology (ESM). The proposed methodology determines the parameters for the interaction between nodes in the network by estimating a multilevel vector autoregression (VAR) model on the data. The methodology allows combining between-subject and within-subject information in a multilevel framework. The resulting network architecture can subsequently be analyzed through network analysis techniques. In the present study, we apply the method to a set of items that assess mood-related factors. We show that the analysis generates a plausible and replicable network architecture, the structure of which is related to variables such as neuroticism; that is, for subjects who score high on neuroticism, worrying plays a more central role in the network. Implications and extensions of the methodology are discussed.