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Sankt Peter-Ording, Germany

Just T.,University of Rostock | Lankenau E.,University of Lu beck | Prall F.,University of Rostock | Huttmann G.,University of Lu beck | And 2 more authors.
Laryngoscope | Year: 2010

Objectives/Hypothesis: A newly developed microscope-based spectral-domain optical coherence tomography (SD-OCT) device and an endoscopebased time-domain OCT (TD-OCT) were used to assess the inter-rater reliability, sensitivity, specificity, and accuracy of benign and dysplastic laryngeal epithelial lesions. Study Design: Prospective study. Methods: OCT during microlaryngoscopy was done on 35 patients with an endoscope-based TDOCT, and on 26 patients by an SD-OCT system integrated into an operating microscope. Biopsies were taken from microscopically suspicious lesions allowing comparative study of OCT images and histology. Results: Thickness of the epithelium was seen to be the main criterion for degree of dysplasia. The inter-rater reliability for two observers was found to be kappa = 0.74 (P <.001) for OCT. OCT provided test outcomes for differentiation between benign laryngeal lesions and dysplasia/CIS with sensitivity of 88%, specificity of 89%, PPV of 85%, NPV of 91%, and predictive accuracy of 88%. However, because of the limited penetration depth of the laser light primarily in hyperkeratotic lesions (thickness above 1.5 mm), the basal cell layer was no longer visible, precluding reliable assessment of such lesions. Conclusions: OCT allows for a fairly accurate assessment of benign and dysplastic laryngeal epithelial lesion and greatly facilitates the taking of precise biopsies. © 2010 The American Laryngological, Rhinological and Otological Society, Inc. Source

Oyanedel C.N.,University of Tu Bingen | Binder S.,University of Lu beck | Kelemen E.,University of Tu Bingen | Petersen K.,University of Lu beck | And 3 more authors.
Behavioural Brain Research | Year: 2014

Our previous experiments showed that sleep in rats enhances consolidation of hippocampus dependent episodic-like memory, i.e. the ability to remember an event bound into specific spatio-temporal context. Here we tested the hypothesis that this enhancing effect of sleep is linked to the occurrence of slow oscillatory and spindle activity during slow wave sleep (SWS). Rats were tested on an episodic-like memory task and on three additional tasks covering separately the where (object place recognition), when (temporal memory), and what (novel object recognition) components of episodic memory. In each task, the sample phase (encoding) was followed by an 80-min retention interval that covered either a period of regular morning sleep or sleep deprivation. Memory during retrieval was tested using preferential exploration of novelty vs. familiarity. Consistent with previous findings, the rats which had slept during the retention interval showed significantly stronger episodic-like memory and spatial memory, and a trend of improved temporal memory (although not significant). Object recognition memory was similarly retained across sleep and sleep deprivation retention intervals. Recall of episodic-like memory was associated with increased slow oscillatory activity (0.85-2.0. Hz) during SWS in the retention interval. Spatial memory was associated with increased proportions of SWS. Against our hypothesis, a relationship between spindle activity and episodic-like memory performance was not detected, but spindle activity was associated with object recognition memory. The results provide support for the role of SWS and slow oscillatory activity in consolidating hippocampus-dependent memory, the role of spindles in this process needs to be further examined. © 2014 The Authors. Source

Riba J.,Institute Of Recerca | Heldmann M.,University of Lu beck | Carreiras M.,Basque Center on Cognition | Carreiras M.,Ikerbasque | Munte T.F.,University of Lu beck
NeuroReport | Year: 2010

Using functional magnetic resonance imaging the neural activity associated with error commission and conflict monitoring in a lexical decision task was assessed. In a cohort of 20 native speakers of Spanish conflict was introduced by presenting words with high and low lexical frequency and pseudo-words with high and low syllabic frequency for the first syllable. Erroneous versus correct responses showed activation in the frontomedial and left inferior frontal cortex. A similar pattern was found for correctly classified words of low versus high lexical frequency and for correctly classified pseudo-words of high versus low syllabic frequency. Conflict-related activations for language materials largely overlapped with error-induced activations. The effect of syllabic frequency underscores the role of sublexical processing in visual word recognition and supports the view that the initial syllable mediates between the letter and word level. © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins. Source

Pichler I.,European Academy Bozen Bolzano | Pichler I.,University of Chicago | Fuchsberger C.,European Academy Bozen Bolzano | Fuchsberger C.,University of Chicago | And 8 more authors.
European Journal of Human Genetics | Year: 2010

Although the North American Hutterites trace their origins to South Tyrol, no attempts have been made to examine the genetic migration history of the Hutterites before emigrating to the United States in the 1870s. To investigate this, we studied 9 microsatellite loci and 11 unique event polymorphism (UEP) markers on the Y-chromosome, the hypervariable region I (HVRI) of the mitochondrial DNA (mtDNA), as well as the complete mtDNA genome of Hutterite and South Tyrolean samples. Only 6 out of 14 Y-chromosome UEPmicrosatellite haplotypes and 3 out of 11 mitochondrial haplotypes that were present in the Hutterites were also present in the South Tyrolean population. The phylogenetic relationships inferred from Y-chromosome and mtDNA databases show that the Hutterites have a unique genetic background related to a similar extent to central and eastern European populations. An admixture analysis indicates, however, a relatively high genetic contribution of central European populations to the Hutterite gene pool. These results are consistent with historical records on Hutterite migrations and demographic history. In addition, our data reveal similar numbers of Y and mitochondrial haplotypes in Hutterite male and female founders, respectively. The Hutterite male and female gene pools are similar with respect to genetic diversity and genetic distance measures and comparable with respect to their origins, suggesting a similar evolutionary history. © 2010 Macmillan Publishers Limited All rights reserved. Source

Dahl M.C.,Eden Inc | Ahrens M.,University of Lu beck | Sherman J.E.,Twin Cities Orthopedics | Martz E.O.,Eden Inc
Spine | Year: 2010

Study Design. A validated L3-L4 nonlinear finite element model was used to evaluate strain and pressure in the surrounding structures for 4 nucleus replacement technologies. Objective. The objective of the current study was to compare subsidence and anular damage potential between 4 current nucleus replacement technologies. It was hypothesized that a fully conforming nucleus replacement would minimize the risk of both subsidence and anular damage. Summary of Background Data. Nucleus pulposus replacements are emerging as a less invasive alternative to total disc replacement and fusion as a solution to degenerative intervertebral discs. Multiple technologies have been developed and are currently undergoing clinical investigation. Methods. The testing conditions were applied by excavating the nucleus of the intact model and virtually implanting models representing the various nucleus replacement technologies. The implants consisted of a conforming injectable polyurethane (E = 4 MPa), soft hydrogel (E = 4 MPa), stiff hydrogel (E = 20 MPa), and polyether-etherketone (PEEK) on PEEK articulating designs. The model was exercised in flexion, extension, lateral bending, axial rotation (7.5 Nm with 450 N preload), and compression (1000 N). Vertebral body strain, anular maximum shear strain, endplate contact pressure, anulus-implant contact pressure, and bone remodeling stimulus were reported. Results. The PEEK implant induced strain maxima in the vertebral bodies with associated endplate contact pressure concentrations. For the PEEK and hydrogel implants, areas of nonconformity with the endplate indicatedadjacent bone resorption. Lack of conformity between the implant and inner anulus for the PEEK and hydrogel implants resulted in inward anular bulging with associated increased maximum shear strain. The conforming polyurethane implant maintained outward bulging of the inner anular wall and indicated no bone resorption or stress shielding adjacent to the implant. Conclusion. A fully conforming nucleus replacement resulted in a decreased propensity for subsidence, anular bulging, and further degeneration of the anulus when compared with nonconforming implants. © 2010, Lippincott Williams & Wilkins. Source

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