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.

Network Embeddedness and the Exploration of Novel Technologies: Technological Distance, Betweenness Centrality and Density

Abstract: In this paper we analyze the innovative performance of alliance networks as a function of the technological distance between partners, a firm's network position (centrality) and total network density. We study how these three elements of an alliance network, apart and in combination, affect the 'twin tasks' in exploration, namely novelty creation on the one hand and its efficient absorption on the other hand. For an empirical test, we study technology-based alliance networks in the pharmaceutical, chemical and automotive industry.

The Strengths and Difficulties Questionnaire (SDQ)--further evidence for its reliability and validity in a community sample of Dutch children and adolescents.

Abstract: This study was a first attempt to examine the psychometric properties of the Strengths and Difficulties Questionnaire (SDQ) in Dutch youths. A large sample of normal children and adolescents (N = 562) and their parents completed the SDQ along with a number of other psychopathology measures. Factor analysis of the SDQ yielded five factors that were in keeping with the hypothesised subscales of hyperactivity-inattention, emotional symptoms, peer problems, conduct problems, and prosocial behaviour. Furthermore, internal consistency, test-retest stability, and parent-youth agreement of the various SDQ scales were acceptable. Finally, the concurrent validity of the SDQ was good: that is, its scores correlated in a theoretically meaningful way with other measures of psychopathology. It can be concluded that the psychometric properties of the parent- and self-report version of the SDQ were satisfactory in this Dutch community sample. Moreover, the current data provide further support for the utility of the SDQ as an index of psychopathological symptoms in youths.

Fibril structure of amyloid-β(1-42) by cryo-electron microscopy.

Abstract: Amyloids are implicated in neurodegenerative diseases. Fibrillar aggregates of the amyloid-β protein (Aβ) are the main component of the senile plaques found in brains of Alzheimer’s disease patients. We present the structure of an Aβ(1–42) fibril composed of two intertwined protofilaments determined by cryo–electron microscopy (cryo-EM) to 4.0-angstrom resolution, complemented by solid-state nuclear magnetic resonance experiments. The backbone of all 42 residues and nearly all side chains are well resolved in the EM density map, including the entire N terminus, which is part of the cross-β structure resulting in an overall “LS”-shaped topology of individual subunits. The dimer interface protects the hydrophobic C termini from the solvent. The characteristic staggering of the nonplanar subunits results in markedly different fibril ends, termed “groove” and “ridge,” leading to different binding pathways on both fibril ends, which has implications for fibril growth.

Randomized trial of cyclophosphamide versus methotrexate for induction of remission in early systemic antineutrophil cytoplasmic antibody–associated vasculitis

Abstract: Objective. Standard therapy for antineutrophil cytoplasmic antibody-associated systemic vasculitis (AASV) with cyclophosphamide (CYC) and prednisolone is limited by toxicity. This unblinded, prospective, randomized, controlled trial was undertaken to determine whether methotrexate (MTX) could replace CYC in the early treatment of AASV. Methods. Patients with newly diagnosed AASV, with serum creatinine levels <150 mu moles/liter, and without critical organ manifestations of disease were randomized to receive either standard oral CYC, 2 mg/kg/day or oral MTX, 20-25 mg/week; both groups received the same prednisolone regimen. All drug treatments were gradually tapered and withdrawn by 12 months. Followup continued to 18 months. The primary end point was the remission rate at 6 months (noninferiority testing). Results. One hundred patients were recruited from 26 European centers; 51 patients were randomized to the MTX group and 49 to the CYC group. At 6 months, the remission rate in patients treated with MTX (89.8%) was not inferior to that in patients treated with CYC (93.5%) (P = 0.041). In the MTX group, remission was delayed among patients with more extensive disease (P = 0.04) or pulmonary involvement (P = 0.03). Relapse rates at 18 months were 69.5% in the MTX group and 46.5% in the CYC group; the median time from remission to relapse was 13 months and 15 months, respectively (P = 0.023, log rank test). Two patients from each group died. Adverse events (mean 0.87 episodes/patient) included leukopenia, which was less frequent in the MTX versus the CYC group (P = 0.012), and liver dysfunction, which was more frequent in the MTX group (P = 0.036). Conclusion. MTX can replace CYC for initial treatment of early AASV. The MTX regimen used in the present study was less effective for induction of remission in patients with extensive disease and pulmonary involvement and was associated with more relapses than the CYC regimen after termination of treatment. The high relapse rates in both treatment arms support the practice of continuation of immunosuppressive treatment beyond 12 months.