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PubMed | Apptomics LLC, Tel Aviv University, Harvard University, The Interdisciplinary Center and 20 more.
Type: Journal Article | Journal: Movement disorders : official journal of the Movement Disorder Society | Year: 2016

The miniaturization, sophistication, proliferation, and accessibility of technologies are enabling the capture of more and previously inaccessible phenomena in Parkinsons disease (PD). However, more information has not translated into a greater understanding of disease complexity to satisfy diagnostic and therapeutic needs. Challenges include noncompatible technology platforms, the need for wide-scale and long-term deployment of sensor technology (among vulnerable elderly patients in particular), and the gap between the big data acquired with sensitive measurement technologies and their limited clinical application. Major opportunities could be realized if new technologies are developed as part of open-source and/or open-hardware platforms that enable multichannel data capture sensitive to the broad range of motor and nonmotor problems that characterize PD and are adaptable into self-adjusting, individualized treatment delivery systems. The International Parkinson and Movement Disorders Society Task Force on Technology is entrusted to convene engineers, clinicians, researchers, and patients to promote the development of integrated measurement and closed-loop therapeutic systems with high patient adherence that also serve to (1) encourage the adoption of clinico-pathophysiologic phenotyping and early detection of critical disease milestones, (2) enhance the tailoring of symptomatic therapy, (3) improve subgroup targeting of patients for future testing of disease-modifying treatments, and (4) identify objective biomarkers to improve the longitudinal tracking of impairments in clinical care and research. This article summarizes the work carried out by the task force toward identifying challenges and opportunities in the development of technologies with potential for improving the clinical management and the quality of life of individuals with PD. 2016 International Parkinson and Movement Disorder Society.

Ross C.A.,Johns Hopkins University | Aylward E.H.,Seattle Childrens Research Institute | Wild E.J.,University College London | Langbehn D.R.,University of Iowa | And 11 more authors.
Nature Reviews Neurology | Year: 2014

Huntington disease (HD) can be seen as a model neurodegenerative disorder, in that it is caused by a single genetic mutation and is amenable to predictive genetic testing, with estimation of years to predicted onset, enabling the entire range of disease natural history to be studied. Structural neuroimaging biomarkers show that progressive regional brain atrophy begins many years before the emergence of diagnosable signs and symptoms of HD, and continues steadily during the symptomatic or 'manifest' period. The continued development of functional, neurochemical and other biomarkers raises hopes that these biomarkers might be useful for future trials of disease-modifying therapeutics to delay the onset and slow the progression of HD. Such advances could herald a new era of personalized preventive therapeutics. We describe the natural history of HD, including the timing of emergence of motor, cognitive and emotional impairments, and the techniques that are used to assess these features. Building on this information, we review recent progress in the development of biomarkers for HD, and potential future roles of these biomarkers in clinical trials. © 2014 Macmillan Publishers Limited.

PubMed | Australian Catholic University, Monash University, George Huntington Institute, Leiden University and 4 more.
Type: Journal Article | Journal: Neuropsychologia | Year: 2015

The occipital lobe is an important visual processing region of the brain. Following consistent findings of early neural changes in the occipital lobe in Huntingtons Disease (HD), we examined cortical thickness across four occipital regions in premanifest (preHD) and early HD groups compared with controls. Associations between cortical thickness in gene positive individuals and performance on six cognitive tasks, each with a visual component, were examined. In addition, the association between cortical thickness in gene positive participants and one non-visual motor task was also examined for comparison.Cortical thickness was determined using FreeSurfer on T1-weighted 3T MR datasets from controls (N=97), preHD (N=109) and HD (N=69) from the TRACK-HD study. Regression models were fitted to assess between-group differences in cortical thickness, and relationships between performance on the cognitive tasks, the motor task and occipital thickness were examined in a subset of gene-positive participants (N=141).Thickness of the occipital cortex in preHD and early HD participants was reduced compared with controls. Regionally-specific associations between reduced cortical thickness and poorer performance were found for five of the six cognitive tasks, with the strongest associations in lateral occipital and lingual regions. No associations were found with the cuneus. The non-visual motor task was not associated with thickness of any region.The heterogeneous pattern of associations found in the present study suggests that occipital thickness negatively impacts cognition, but only in regions that are linked to relatively advanced visual processing (e.g., lateral occipital, lingual regions), rather than in basic visual processing regions such as the cuneus. Our results show, for the first time, the functional implications of occipital atrophy highlighted in recent studies in HD.

PubMed | University of Veterinary Medicine Hannover, Huntington University, Academy of Sciences of the Czech Republic and George Huntington Institute
Type: | Journal: Journal of neuroscience methods | Year: 2016

While several novel therapeutic approaches for HD are in development, resources to conduct clinical trials are limited. Large animal models have been proposed to improve assessment of safety, tolerability and especially to increase translational reliability of efficacy signals obtained in preclinical studies. They may thus help to select candidates for translation to human studies. We here introduce a battery of novel tests designed to assess the motor, cognitive and behavioral phenotype of a transgenic (tg) HD minipig model.A group of tgHD and wildtype (wt) Libechov minipigs (n=36) was available for assessment with (1) a gait test using the GAITRite() automated acquisition system, (2) a hurdle-test, (3) a tongue coordination test, (4) a color discrimination test, (5) a startbox back and forth test and (6) a dominance test. Performance of all tests and definition of measures obtained is presented.Minipigs were able to learn performance of all tests. All tests were safe, well tolerated and feasible. Exploratory between group comparisons showed no differences between groups of tgHD and wt minipigs assessed, but low variability within and between groups.So far there are no established or validated assessments to test minipigs in the domains described.The data shows that the tests presented are safe, well tolerated and all measures defined can be assessed. Prospective longitudinal application of these tests is warranted to determine their test-retest reliability, sensitivity and validity in assessing motor, cognitive and behavioral features of tg and wt minipigs.

Reilmann R.,George Huntington Institute | Reilmann R.,University of Tuebingen | Leavitt B.R.,University of British Columbia | Ross C.A.,Johns Hopkins University
Movement Disorders | Year: 2014

Huntington's disease (HD) is currently diagnosed based on the presence of motor signs indicating 99% "diagnostic confidence" for HD. Recent advances in the understanding of HD natural history and neurobiology indicate that disease-related brain changes begin at least 12 to 15 years before the formal diagnosis based on motor onset. Furthermore, subtle motor dysfunction, cognitive changes, and behavioral alterations are often seen before diagnosis made according to the current criteria. As disease-modifying treatments are developed, likely beginning therapy early will be desirable. We therefore suggest that expanded diagnostic criteria for HD should be adapted to better reflect the natural history of the disease, to enable the conduct of clinical trials in premanifest subjects targeting prevention of neurodegeneration, and to facilitate earlier symptomatic treatment. We propose a new set of criteria for HD diagnostic categories in the International Classification of Diseases that reflect our current understanding of HD natural history and pathogenesis. Based on defined criteria, for example, the Diagnostic Confidence Level and the Total Functional Capacity scales of the Unified Huntington's Disease Rating Scale, HD should be divided in the categories "genetically confirmed" with the subcategories "presymptomatic," "prodromal," and "manifest" and "not genetically confirmed" subdivided into "clinically at risk," "clinically prodromal," and "clinically manifest." 2014 International Parkinson and Movement Disorder Society .

PubMed | Charité - Medical University of Berlin and George Huntington Institute
Type: | Journal: BMC neurology | Year: 2015

Muscular weakness in myasthenia gravis (MG) is commonly assessed using Quantitative Myasthenia Gravis Score (QMG). More objective and quantitative measures may complement the use of clinical scales and might detect subclinical affection of muscles. We hypothesized that muscular weakness in patients with MG can be quantified with the non-invasive Quantitative Motor (Q-Motor) test for Grip Force Assessment (QGFA) and Involuntary Movement Assessment (QIMA) and that pathological findings correlate with disease severity as measured by QMG.This was a cross-sectional pilot study investigating patients with confirmed diagnosis of MG. Data was compared to healthy controls (HC). Subjects were asked to lift a device (250 and 500g) equipped with electromagnetic sensors that measured grip force (GF) and three-dimensional changes in position and orientation. These were used to calculate the position index (PI) and orientation index (OI) as measures for involuntary movements due to muscular weakness.Overall, 40 MG patients and 23 HC were included. PI and OI were significantly higher in MG patients for both weights in the dominant and non-dominant hand. Subgroup analysis revealed that patients with clinically ocular myasthenia gravis (OMG) also showed significantly higher values for PI and OI in both hands and for both weights. Disease severity correlates with QIMA performance in the non-dominant hand.Q-Motor tests and particularly QIMA may be useful objective tools for measuring motor impairment in MG and seem to detect subclinical generalized motor signs in patients with OMG. Q-Motor parameters might serve as sensitive endpoints for clinical trials in MG.

Sampaio C.,CHDI Management CHDI Foundation | Borowsky B.,CHDI Management CHDI Foundation | Reilmann R.,George Huntington Institute | Reilmann R.,University of Tübingen
Movement Disorders | Year: 2014

Since the identification of the Huntington's disease (HD) gene, knowledge has accumulated about mechanisms directly or indirectly affected by the mutated Huntingtin protein. Transgenic and knock-in animal models of HD facilitate the preclinical evaluation of these targets. Several treatment approaches with varying, but growing, preclinical evidence have been translated into clinical trials. We review major landmarks in clinical development and report on the main clinical trials that are ongoing or have been recently completed. We also review clinical trial settings and designs that influence drug-development decisions, particularly given that HD is an orphan disease. In addition, we provide a critical analysis of the evolution of the methodology of HD clinical trials to identify trends toward new processes and endpoints. Biomarker studies, such as TRACK-HD and PREDICT-HD, have generated evidence for the potential usefulness of novel outcome measures for HD clinical trials, such as volumetric imaging, quantitative motor (Q-Motor) measures, and novel cognitive endpoints. All of these endpoints are currently applied in ongoing clinical trials, which will provide insight into their reliability, sensitivity, and validity, and their use may expedite proof-of-concept studies. We also outline the specific opportunities that could provide a framework for a successful avenue toward identifying and efficiently testing and translating novel mechanisms of action in the HD field. © 2014 International Parkinson and Movement Disorder Society.

PubMed | University College London, George Huntington Institute, University of Munster, RWTH Aachen and Marienhospital Aachen
Type: | Journal: BMC neurology | Year: 2015

Deterioration of fine motor control of the tongue is common in Multiple Sclerosis (MS) and has a major impact on quality of life. However, the underlying neuronal substrate is largely unknown. Here, we aimed to explore the association of tongue motor dysfunction in MS patients with overall clinical disability and structural brain damage.We employed a force transducer based quantitative-motor system (Q-Motor) to objectively assess tongue function in 33 patients with MS. The variability of tongue force output (TFV) and the mean applied tongue force (TF) were measured during an isometric tongue protrusion task. Twenty-three age and gender matched healthy volunteers served as controls. Correlation analyses of motor performance in MS patients with individual disease burden as expressed by the Expanded Disability Status Scale (EDSS) and with microstructural brain damage as measured by the fractional anisotropy (FA) on Diffusion Tensor Imaging were performed.MS patients showed significantly increased TFV and decreased TF compared to controls (p < 0.02). TFV but not TF was correlated with the EDSS (p < 0.04). TFV was inversely correlated with FA in the bilateral posterior limb of the internal capsule expanding to the brain stem (p < 0.001), a region critical to tongue function. TF showed a weaker, positive and unilateral correlation with FA in the same region (p < 0.001).Changes in TFV were more robust and correlated better with disease phenotype and FA changes than TF. TFV might serve as an objective and non-invasive outcome measure to augment the quantitative assessment of motor dysfunction in MS.

Schubert R.,University of Munster | Schubert R.,George Huntington Institute | Vollmer A.,University of Munster | Ketelhut S.,University of Munster | Kemper B.,University of Munster
Biomedical Optics Express | Year: 2014

Self-interference digital holographic microscopy (DHM) has been found particular suitable for simplified quantitative phase imaging of living cells. However, a main drawback of the self-interference DHM principle are scattering patterns that are induced by the coherent nature of the laser light which affect the resolution for detection of optical path length changes. We present a simple and efficient technique for the reduction of coherent disturbances in quantitative phase images. Therefore, amplitude and phase of the sample illumination are modulated by an electrically focus tunable lens. The proposed method is in particular convenient with the selfinterference DHM concept. Results from the characterization of the method show that a reduction of coherence induced disturbances up to 70 percent can be achieved. Finally, the performance for enhanced quantitative imaging of living cells is demonstrated. © 2014 Optical Society of America.

PubMed | George Huntington Institute
Type: Journal Article | Journal: Journal of Huntington's disease | Year: 2015

FDG-PET detects hypometabolism in premanifest and symptomatic Huntingtons disease (HD). A cross-sectional study suggested that whole-brain FDG-PET is capable to detect a phenotype in transgenic (tg) HD rats. Recently, a longitudinal follow-up study showed no FDG-PET changes in tgHD rats. Both studies applied small sample sizes and analysis was limited to whole-brain or striatum.We therefore performed a follow-up study in a larger cohort of tgHD and wild-type (wt) rats encompassing several pre-defined regions of interest (ROIs) and hypothesis free voxel-by-voxel SPM analysis to clarify whether FDG-PET can detect a phenotype in tgHD rats and to determine onset and effect sizes of changes over time.N = 19 tgHD- and n = 20 wt-rats, mixed gender, were included. Repeated small animal FDG-PET and MRI were performed at 5,10,15, and 20 months of age. ROIs encompassing entire brain, cortex, striatum, thalamus, subventricular-zone, and cerebellum were placed manually on the MRI and transferred to the co-registered PET. Mean and maximal FDG-PET activities within ROIs were calculated and normalized to cerebellar FDG uptake. Activity and spatially normalized FDG-PET were compared between groups on a hypothesis-free voxel-by-voxel basis using SPM.FDG uptake showed changes over time in both tgHD- and wt-rats, however, there was no consistent difference between tgHD- and wt-rats in both the manual ROI and SPM analysis.In this transgenic rat model of HD FDG-PET imaging does not detect significant alterations at the ages investigated. Further investigations are warranted employing other age groups and alternative imaging biomarkers for neuronal degeneration, respectively.

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