Publications

959 Publications visible to you, out of a total of 959

Abstract (Expand)

PURPOSE: Daytime sleepiness is associated with several medical problems. The aim of this paper is to provide normative values for one of the most often used questionnaires measuring daytime sleepiness, the Epworth Sleepiness Scale (ESS). METHODS: A large sample of 9711 people from the German general population took part in this study. In addition to the ESS, several other questionnaires were used, and sociodemographic and behavioral factors were recorded. RESULTS: Normative values for the ESS are given. According to the generally accepted criterion ESS > 10, 23 % of the sample showed excessive daytime sleepiness. Males reported significantly more daytime sleepiness than females (effect size d = 0.19). In the age range of 40-80 years, a continuous decline of daytime sleepiness was observed. Psychometric properties of the ESS were good. Alcohol intake and nicotine consumption were marginally associated with daytime sleepiness, and obese people reported significantly more sleepiness than people of normal weight (OR = 1.39). CONCLUSIONS: The normative tables allow clinicians and researchers to assess the degree of their patients' daytime sleepiness, especially in the upper range of scores.

Authors: C. Sander, U. Hegerl, K. Wirkner, N. Walter, R. D. Kocalevent, K. Petrowski, H. Glaesmer, A. Hinz

Date Published: 29th May 2016

Publication Type: Journal article

Abstract (Expand)

Speckle tracking echocardiography (STE) is a widespread method for calculating myocardial strains and estimating left ventricle function. Since echocardiographic clips are corrupted by speckle decorrelation noise, resulting in irregular, nonphysiological tissue displacement fields, smoothing is performed on the displacement data, affecting the strain results. Thus, strain results may depend on the specific implementations of 2-D STE, as well as other systems' characteristics of the various vendors. A novel algorithm (called K-SAD) is introduced, which integrates the physiological constraint of smoothness of the displacement field into an optimization process. Simulated B-mode clips, modeling healthy and abnormal cases, were processed by K-SAD. Peak global and subendocardial longitudinal strains, as well as regional strains, were calculated. In addition, 410 healthy subjects were also processed. The results of K-SAD are compared with those of one of the leading commercial product. K-SAD provides global mid-wall strain values, as well as subendocardial and regional strain values, all in good agreement with the ground-truth-simulated phantom data. K-SAD peak global longitudinal systolic strain values for 410 healthy subjects are quite similar for the different regions: - 17.02 +/- 4.02%, - 19.00 +/- 3.45%, and - 19.72 +/- 5.06% at the basal, mid, and apical regions, respectively. Improved performance under noisy conditions was demonstrated by comparing a subgroup of 40 subjects with the best image quality with the remaining 370 cohort: K-SAD provides statistically similar global and regional results for the two cohorts. Our study indicates that the sensitivity of strain values to speckle noise, caused by the post block-matching weighted smoothing, can be significantly reduced and accuracy enhanced by employing an integrated one-stage, physiologically constrained optimization process.

Authors: H. Khamis, S. Shimoni, A. Hagendorff, N. Smirin, Z. Friedman, D. Adam

Date Published: 24th May 2016

Publication Type: Journal article

Abstract (Expand)

Lung diseases are described by a wide variety of developmental mechanisms and clinical manifestations. Accurate classification and diagnosis of lung diseases are the bases for development of effective treatments. While extensive studies are conducted toward characterization of various lung diseases at molecular level, no systematic approach has been developed so far. Here we have applied a methodology for pathway-centered mining of high throughput gene expression data to describe a wide range of lung diseases in the light of shared and specific pathway activity profiles. We have applied an algorithm combining a Pathway Signal Flow (PSF) algorithm for estimation of pathway activity deregulation states in lung diseases and malignancies, and a Self Organizing Maps algorithm for classification and clustering of the pathway activity profiles. The analysis results allowed clearly distinguish between cancer and non-cancer lung diseases. Lung cancers were characterized by pathways implicated in cell proliferation, metabolism, while non-malignant lung diseases were characterized by deregulations in pathways involved in immune/inflammatory response and fibrotic tissue remodeling. In contrast to lung malignancies, chronic lung diseases had relatively heterogeneous pathway deregulation profiles. We identified three groups of interstitial lung diseases and showed that the development of characteristic pathological processes, such as fibrosis, can be initiated by deregulations in different signaling pathways. In conclusion, this paper describes the pathobiology of lung diseases from systems viewpoint using pathway centered high-dimensional data mining approach. Our results contribute largely to current understanding of pathological events in lung cancers and non-malignant lung diseases. Moreover, this paper provides new insight into molecular mechanisms of a number of interstitial lung diseases that have been studied to a lesser extent.

Authors: A. Arakelyan, L. Nersisyan, M. Petrek, H. Loffler-Wirth, H. Binder

Date Published: 21st May 2016

Publication Type: Not specified

Human Diseases: lung disease

Abstract (Expand)

Pneumonia is considered to be one of the leading causes of death worldwide. The outcome depends on both, proper antibiotic treatment and the effectivity of the immune response of the host. However, due to the complexity of the immunologic cascade initiated during infection, the latter cannot be predicted easily. We construct a biomathematical model of the murine immune response during infection with pneumococcus aiming at predicting the outcome of antibiotic treatment. The model consists of a number of non-linear ordinary differential equations describing dynamics of pneumococcal population, the inflammatory cytokine IL-6, neutrophils and macrophages fighting the infection and destruction of alveolar tissue due to pneumococcus. Equations were derived by translating known biological mechanisms and assuming certain response kinetics. Antibiotic therapy is modelled by a transient depletion of bacteria. Unknown model parameters were determined by fitting the predictions of the model to data sets derived from mice experiments of pneumococcal lung infection with and without antibiotic treatment. Time series of pneumococcal population, debris, neutrophils, activated epithelial cells, macrophages, monocytes and IL-6 serum concentrations were available for this purpose. The antibiotics Ampicillin and Moxifloxacin were considered. Parameter fittings resulted in a good agreement of model and data for all experimental scenarios. Identifiability of parameters is also estimated. The model can be used to predict the performance of alternative schedules of antibiotic treatment. We conclude that we established a biomathematical model of pneumococcal lung infection in mice allowing predictions regarding the outcome of different schedules of antibiotic treatment. We aim at translating the model to the human situation in the near future.

Authors: Sibylle Schirm, Peter Ahnert, Sandra Wienhold, Holger Mueller-Redetzky, Geraldine Nouailles-Kursar, Markus Loeffler, Martin Witzenrath, Markus Scholz

Date Published: 19th May 2016

Publication Type: Journal article

Abstract (Expand)

Negative emotional stimuli are particularly salient events that receive privileged access to neurocognitive resources. At the neural level, the processing of negative stimuli relies on a set of sensory, limbic, and prefrontal areas. However, controversies exist on how demographic and task-related characteristics modulate this brain pattern. Here, we used activation likelihood estimation (ALE) meta-analysis and replicator dynamics to investigate the processing of negative visual stimuli in healthy adults. Our findings endorse the central role of the amygdala. This result might reflect how this structure modulates perceptual and attentional mechanisms in response to emotional stimuli. Additionally, we characterize how the neural processing of negative visual stimuli is influenced by the demographic factors of age and sex as well as by task-related characteristics like stimulus type, emotion category, and task instruction, with the amygdala showing comparable engagement across different sexes, stimulus types, and task instructions. Our findings practically inform experimentation in the affective neurosciences but also suggest brain circuits for neurobiological investigations of affective symptomatology.

Authors: I. Garcia-Garcia, J. Kube, M. Gaebler, A. Horstmann, A. Villringer, J. Neumann

Date Published: 12th May 2016

Publication Type: Not specified

Abstract (Expand)

Treatment of relapse and primary progression in aggressive lymphoma remains unsatisfactory; outcome is still poor. Better treatment strategies are much needed for this patient population. The R1 study is a prospective multi-center phase I/II study evaluating a dose finding approach with a triple transplant regimen in four BEAM dose levels in patients with relapsed aggressive non-Hodgkin lymphoma. The aim of the study was to determine feasibility, toxicity, and remission rate. In a total of 39 patients (pts.) enrolled in the study, 24 pts. were evaluated in the following analysis. Twenty pts. had aggressive B cell lymphoma, and two pts. had T cell lymphoma. All evaluated patients responded to DexaBEAM with a sufficient stem cell harvest. The phase I/II study was started with BEAM dose level II. Four patients were treated at dose level II, and 20 pts. were treated at dose level III. Due to the early termination of the study, dose levels I and IV were never administered. Sixteen pts. completed therapy according to protocol, and eight pts. (33.3 %) stopped treatment early. Infections (27 %) and stomatitis (13 %) were the most frequent grade III/IV non-hematologic toxicities. Thirteen percent of patients presented with severe grade III/IV lung toxicity during modified BEAM (m-BEAM). Fourteen pts. achieved a complete response (CR), one pt. achieved no change (NC), six pts. had progressive disease (PD), and two pts. died; for one pt., outcome is not known. One-year and 3-year event-free survival (EFS) was 38 and 33 %, respectively. Overall survival (OS) after 1 and 3 years was 50 and 38 %. In conclusion, dose escalation of standard BEAM is not feasible due to toxicity.

Authors: K. Hohloch, S. Zeynalova, B. Chapuy, M. Pfreundschuh, M. Loeffler, M. Ziepert, A. C. Feller, L. Trumper, D. Hasenclever, G. Wulf, N. Schmitz

Date Published: 12th May 2016

Publication Type: Not specified

Human Diseases: non-Hodgkin lymphoma

Abstract (Expand)

Dopamine has been implicated in the regulation of sleep-wake states and the circadian rhythm. However, there is no consensus on the impact of two established dopaminergic gene variants: the catechol-O-methyltransferase Val158Met (COMT Val158Met; rs4680) and the dopamine D4 receptor Exon III variable-number-of-tandem-repeat polymorphism (DRD4 VNTR). Pursuing a multi-method approach, we examined their potential effects on circadian preferences, arousal regulation and sleep. Subjects underwent a 7-day actigraphy assessment (SenseWear Pro3), a 20-minute resting EEG (analyzed using VIGALL 2.0) and a body mass index (BMI) assessment. Further, they completed the Morningness-Eveningness Questionnaire (MEQ), the Epworth Sleepiness Scale (ESS) and the Pittsburgh Sleep Quality Index (PSQI). The sample comprised 4625 subjects (19-82 years) genotyped for COMT Val158Met, and 689 elderly subjects (64-82 years) genotyped for DRD4 VNTR. The number of subjects varied across phenotypes. Power calculations revealed a minimum required phenotypic variance explained by genotype ranging between 0.5% and 1.5% for COMT Val158Met and between 3.3% and 6.0% for DRD4 VNTR. Analyses did not reveal significant genotype effects on MEQ, ESS, PSQI, BMI, actigraphy and EEG variables. Additionally, we found no compelling evidence in sex- and age-stratified subsamples. Few associations surpassed the threshold of nominal significance (p < .05), providing some indication for a link between DRD4 VNTR and daytime sleepiness. Taken together, in light of the statistical power obtained in the present study, our data particularly suggest no impact of the COMT Val158Met polymorphism on circadian preferences, arousal regulation and sleep. The suggestive link between DRD4 VNTR and daytime sleepiness, on the other hand, might be worth investigation in a sample enriched with younger adults.

Authors: P. Jawinski, S. Tegelkamp, C. Sander, M. Hantzsch, J. Huang, N. Mauche, M. Scholz, J. Spada, C. Ulke, R. Burkhardt, A. Reif, U. Hegerl, T. Hensch

Date Published: 6th May 2016

Publication Type: Not specified

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