Katholieke Universiteit Leuven

About: Katholieke Universiteit Leuven is a education organization based out in Leuven, Belgium. It is known for research contribution in the topics: Population & Context (language use). The organization has 61109 authors who have published 176584 publications receiving 6210872 citations.

Adalimumab induction therapy for Crohn disease previously treated with infliximab: a randomized trial.

Abstract: BACKGROUND Adalimumab, a fully human tumor necrosis factor (TNF) antagonist, is an effective treatment for patients with Crohn disease who are naive to the chimeric TNF antagonist, infliximab. No anti-TNF agent has been evaluated prospectively in patients with Crohn disease who had responded to another anti-TNF agent and then lost that response or were intolerant of the agent. OBJECTIVE To determine whether adalimumab induces remissions more frequently than placebo in adult patients with Crohn disease who have symptoms despite infliximab therapy or who cannot take infliximab because of adverse events. DESIGN 4-week, randomized, double-blind, placebo-controlled trial (November 2004 to December 2005). SETTING 52 sites in the United States, Canada, and Europe. PATIENTS 325 adults 18 to 75 years of age who had a history of Crohn disease for 4 months or more that was moderate to severe at baseline (Crohn's Disease Activity Index [CDAI] score, 220 to 450 points). INTERVENTION Patients were randomly assigned to receive induction doses of adalimumab, 160 mg and 80 mg, at weeks 0 and 2, respectively, or placebo at the same time points. MEASUREMENTS The primary end point was induction of remission at week 4. Decreases in CDAI score by 70 or more and 100 or more points (secondary end points) were also measured. RESULTS A total of 301 patients completed the trial. Twenty-one percent (34 of 159) of patients in the adalimumab group versus 7% (12 of 166) of those in the placebo group achieved remission at week 4 (P < 0.001). The absolute difference in clinical remission rates was 14.2 percentage points (95% CI, 6.7 to 21.6 percentage points). A 70-point response occurred at week 4 in 52% (82 of 159) of patients in the adalimumab group versus 34% (56 of 166) of patients in the placebo group (P = 0.001). The absolute difference in 70-point response rates was 17.8 percentage points (CI, 7.3 to 28.4 percentage points). Two of 159 patients in the adalimumab group and 4 of 166 patients in the placebo group discontinued treatment because of adverse events. No patients in the adalimumab group and 4 of 166 patients in the placebo group had a serious infection. LIMITATIONS The trial did not directly compare alternative active treatments and did not evaluate maintenance of response or long-term immunogenicity of adalimumab. CONCLUSION Adalimumab induces remissions more frequently than placebo in adult patients with Crohn disease who cannot tolerate infliximab or have symptoms despite receiving infliximab therapy. For more information on adalimumab in Crohn disease, click here. ClinicalTrials.gov registration number: NCT00105300.

The impact of agricultural soil erosion on the global carbon cycle

Abstract: Agricultural soil erosion is thought to perturb the global carbon cycle, but estimates of its effect range from a source of 1 petagram per year(-1) to a sink of the same magnitude. By using caesium-137 and carbon inventory measurements from a large-scale survey, we found consistent evidence for an erosion-induced sink of atmospheric carbon equivalent to approximately 26% of the carbon transported by erosion. Based on this relationship, we estimated a global carbon sink of 0.12 (range 0.06 to 0.27) petagrams of carbon per year(-1) resulting from erosion in the world's agricultural landscapes. Our analysis directly challenges the view that agricultural erosion represents an important source or sink for atmospheric CO2.

Self-Calibration and Metric Reconstruction Inspite of Varying and Unknown Intrinsic Camera Parameters

Abstract: In this paper the theoretical and practical feasibility of self-calibration in the presence of varying intrinsic camera parameters is under investigation. The paper‘s main contribution is to propose a self-calibration method which efficiently deals with all kinds of constraints on the intrinsic camera parameters. Within this framework a practical method is proposed which can retrieve metric reconstruction from image sequences obtained with uncalibrated zooming/focusing cameras. The feasibility of the approach is illustrated on real and synthetic examples. Besides this a theoretical proof is given which shows that the absence of skew in the image plane is sufficient to allow for self-calibration. A counting argument is developed which—depending on the set of constraints—gives the minimum sequence length for self-calibration and a method to detect critical motion sequences is proposed.

Practising orientation identification improves orientation coding in V1 neurons

Abstract: The adult brain shows remarkable plasticity, as demonstrated by the improvement in fine sensorial discriminations after intensive practice. The behavioural aspects of such perceptual learning are well documented, especially in the visual system1,2,3,4,5,6,7,8. Specificity for stimulus attributes clearly implicates an early cortical site, where receptive fields retain fine selectivity for these attributes; however, the neuronal correlates of a simple visual discrimination task remained unidentified. Here we report electrophysiological correlates in the primary visual cortex (V1) of monkeys for learning orientation identification. We link the behavioural improvement in this type of learning to an improved neuronal performance of trained compared to naive neurons. Improved long-term neuronal performance resulted from changes in the characteristics of orientation tuning of individual neurons. More particularly, the slope of the orientation tuning curve that was measured at the trained orientation increased only for the subgroup of trained neurons most likely to code the orientation identified by the monkey. No modifications of the tuning curve were observed for orientations for which the monkey had not been trained. Thus training induces a specific and efficient increase in neuronal sensitivity in V1.

The human leukemia cell line, THP-1: A multifacetted model for the study of monocyte-macrophage differentiation

Abstract: THP-1 is a human monocytic leukemia cell line. After treatment with phorbol esters, THP-1 cells differentiate into macrophage-like cells which mimic native monocyte-derived macrophages in several respects. Compared to other human myeloid cell lines, such as HL-60, U937, KG-1, or HEL cell lines, differentiated THP-1 cells behave more like native monocyte-derived macrophages. Because of these characteristics, the THP-1 cell line provides a valuable model for studying the mechanisms involved in macrophage differentiation, and for exploring the regulation of macrophage-specific genes as they relate to physiological functions displayed by these cells.