Oscillation Phase Locking and Late ERP Components of Intracranial Hippocampal Recordings Correlate to Patient Performance in a Working Memory Task

In working memory tasks, stimulus presentation induces a resetting of intracranial temporal lobe oscillations in multiple frequency bands. To further understand the functional relevance of this phenomenon, we investigated whether working memory performance depends on the phase precision of ongoing oscillations in the hippocampus. We recorded intra-hippocampal local field potentials in individuals performing a working memory task. Two types of trials were administered. For high memory trials presentation of a list of four letters ( List ) was followed by a single letter memory probe ( Test ). Low memory load trials, consisting of four identical letters (AAAA) followed by a probe with the same letter (A), were interspersed. Significant phase locking of ongoing oscillations across trials, estimated by the Pairwise Phase Consistency Index (PPCI) was observed in delta (0.5-4 Hz), theta (5-7 Hz), and alpha (8-12 Hz) bands during stimulus presentation and recall but was increased in low memory load trials. Across patients however, higher delta PPCIs during recall in the left hippocampus were associated with faster reaction times. Because phase locking could also be interpreted as a consequence of a stimulus evoked potential, we performed event related potential analysis (ERP) and examined the relationship of ERP components with performance. We found that both amplitude and latency of late ERP components correlated with both reaction time and accuracy. We propose that, in the Sternberg task, phase locking of oscillations, or alternatively its ERP correlate, synchronizes networks within the hippocampus and connected structures that are involved in working memory

Correlation Structures of Correlated Binomial Models and Implied Default Distribution

We show how to analyze and interpret the correlation structures, the conditional expectation values and correlation coefficients of exchangeable Bernoulli random variables. We study implied default distributions for the iTraxx-CJ tranches and some popular probabilistic models, including the Gaussian copula model, Beta binomial distribution model and long-range Ising model. We interpret the differences in their profiles in terms of the correlation structures. The implied default distribution has singular correlation structures, reflecting the credit market implications. We point out two possible origins of the singular behavior.Comment: 16 pages, 7 figure

Minimally invasive coronary artery bypass grafting versus percutaneous transluminal coronary angioplasty with stenting in isolated high-grade stenosis of the proximal left anterior descending coronary artery: Six months' angiographic and clinical follow-up of a prospective randomized study

AbstractObjective: We sought to compare minimally invasive coronary artery bypass grafting (surgical intervention) with percutaneous transluminal coronary angioplasty with primary stenting (stenting) in patients having an isolated high-grade stenosis (American College of Cardiology/American Heart Association classification type B2 or C) of the proximal left anterior descending coronary artery. At 6 months, both procedures were compared on the basis of quantitative angiography and clinical outcome. Methods: Both treatments were compared in a single-center, prospective, randomized study. The primary end point of this study was quantitative angiographic outcome at 6 months. The secondary end point was 6-month clinical outcome. Statistical analysis was performed in accordance with the intention-to-treat principle. Results: From March 1997 to September 1999, patients with angina pectoris caused by an isolated high-grade stenosis of the proximal left anterior descending coronary artery were randomly assigned to surgical intervention (n = 51) or stenting (n = 51). At 6 months, quantitative coronary angiography showed an anastomotic stenosis rate of 4% after surgical intervention and a restenosis rate of 29% after stenting (P <.001). Periprocedural events did not significantly differ between surgical intervention and stenting. After surgical intervention, 2 patients died; no patients died after stenting. After 6 months, no significant difference was found for major adverse cardiac or cerebral events and need for repeat target vessel revascularization. After 6 months, return of angina pectoris, physical work capacity, and use of antianginal drugs did not significantly differ between treatments. Conclusions: After 6 months, surgical intervention had a significantly better angiographic outcome than stenting in patients with an isolated high-grade stenosis of the proximal left anterior descending coronary artery. Clinical outcome did not significantly differ between treatments.J Thorac Cardiovasc Surg 2002;124:130-

Direct observation of free-exciton thermalization in quantum-well structures

We report on a direct observation of free-exciton thermalization in quantum-well structures. A narrow energy distribution of free 1s excitons is created in ZnSe-based quantum wells by emission of one LO phonon after optical excitation of the continuum states with picosecond laser pulses. The subsequent relaxation dynamics within the 1s-exciton dispersion is directly monitored by time-resolved studies of the phonon-assisted photoluminescence. It is demonstrated that the free-exciton distribution remains nonthermal for some 100 ps. The observed dynamics is in reasonable agreement with numerical results of a rate-equation model which accounts for the relevant exciton-phonon coupling mechanisms

Prevalence and influence on outcome of HER2/neu, HER3 and NRG1 expression in patients with metastatic colorectal cancer

Our aim was to explore the impact of the HER2/neu, HER3 receptor as well as their ligands' neuregulin (NRG1) expression on the outcome of patients with metastatic colorectal cancer (mCRC). NRG1, HER2/neu and HER3 expression was evaluated in 208 patients with mCRC receiving 5-FU/LV plus irinotecan or irinotecan plus oxaliplatin as the first-line treatment. Biomarker expression was correlated with the outcome of patients. NRG1 (low: 192 vs. high: 16), HER2/neu (low: 201 vs. high: 7) and HER3 (low: 69 vs. high: 139) expressions were assessed in 208 patients. High versus low NRG1 expression significantly affected progression-free survival (PFS) 4.7 vs. 8.2 months, hazard ratio (HR): 2.45; 95{\%} confidence interval (CI): 1.45-4.13; P=0.001, but not overall survival (OS) (15.5 vs. 20.7 months, HR: 1.33; 95{\%} CI: 0.76-2.35; P=0.32). High versus low HER3 expression (PFS: 7.1 vs. 8.8 months, HR: 1.11; 95{\%} CI: 0.82-1.50; P=0.50; OS: 19.8 vs. 21.1 months, HR: 0.95; 95{\%} CI: 0.70-1.30; P=0.75) and high compared with low HER2/neu expression (PFS: 7.7 vs. 8.0 months, HR: 1.07; 95{\%} CI: 0.71-1.60; P=0.75; OS: 16.6 vs. 21.1 months, HR: 1.13; 95{\%} CI: 0.75-1.71; P=0.57) did not influence outcome. High NRG1 expression was associated with inferior PFS in the FIRE-1 trial. We did not detect a prognostic impact of HER2/neu and HER3 overexpression in mCRC. The frequency of overexpression was comparable with other studies

Effects of MitraClip on cognitive and psychological function in heart failure patients: the sicker the better

Purpose: Cognitive impairment and reduced quality of life is a common condition in patients with heart failure (HF). Percutaneous mitral valve repair using (PMVR) MitraClip (MC) has emerged as a promising interventional tool, reducing all-cause mortality and hospitalization as well as increasing cognitive functioning and quality of life. However, the benefit of HF patients with severely depressed cognitive functioning remains unknown. Methods: We assessed cognitive functioning (figural memory—FGT, executive function—TOL, TMT B), psychosocial functioning (depression—PHQ-9, quality of life—SF36), and clinical parameters (echocardiography, 6-min walk test distance, and cardiac biomarkers) 1 day before (t0) and 6 weeks after (t1) MC intervention in HF patients (n = 40). First, paired sample t tests were conducted to uncover improvements in cognitive functioning post-MC intervention. Second, the COGBAT Norm-sample, a representative age-matched healthy sample, was used to compare participants’ individual scores. Third, bivariate linear regressions were calculated for all key predictors of the detected improvements in cognitive functioning post-MC intervention (t1–t0). Results: Following the MC intervention, we found significant improvements in figural memory, executive functioning, and psychosocial functioning. Most of the patients with depressed executive functioning before the MC intervention showed post-intervention test scores within the normal range (> 50th percentile; t0 22.5% vs. t1 60%) as compared to the normative COGBAT sample. Regression analyses revealed that lower baseline scores in planning ability before the MC intervention (t0) were associated with greater planning ability (TOL; B = − 0.78, 95% CI − 1.04 to − 0.53), figural memory (FGT; B = − 0.26, 95% CI − 0.44 to − 0.07), and cognitive flexibility (TMT B; B = − 0.36, 95% CI − 0.50 to − 0.23) improvement post-MC intervention (t1–t0). Psychosocial functioning and age were not associated with these improvements. Conclusions: Patients with depressed executive functioning showed the greatest benefit from the MC intervention regarding cognitive functioning. Age and psychological functioning seem less important for cognitive performance improvements post-MC intervention. Hence, severely depressed cognitive functioning in patients is not a contraindication for PMVR using MitraClip

Diagnosis of Alzheimer's Disease Based on Disease-Specific Autoantibody Profiles in Human Sera

After decades of Alzheimer's disease (AD) research, the development of a definitive diagnostic test for this disease has remained elusive. The discovery of blood-borne biomarkers yielding an accurate and relatively non-invasive test has been a primary goal. Using human protein microarrays to characterize the differential expression of serum autoantibodies in AD and non-demented control (NDC) groups, we identified potential diagnostic biomarkers for AD. The differential significance of each biomarker was evaluated, resulting in the selection of only 10 autoantibody biomarkers that can effectively differentiate AD sera from NDC sera with a sensitivity of 96.0% and specificity of 92.5%. AD sera were also distinguishable from sera obtained from patients with Parkinson's disease and breast cancer with accuracies of 86% and 92%, respectively. Results demonstrate that serum autoantibodies can be used effectively as highly-specific and accurate biomarkers to diagnose AD throughout the course of the disease

Third Yearly Activity Report

The calculation work performed during the 3rd project year in WP2 as well as the R&amp;D activities carried out in WP3, WP4 and WP5 are described in this report. In addition, the work dedicated to the project management (WP1) as well as to WP6 regarding the dissemination/communication activities and the education/training program (e.g. the follow-up of the mobility program between different organizations in the consortium, training on simulation tools and activities accomplished by PhD/post-doctoral students) is also reported