1,071 research outputs found
Impulsivity in Parkinsonâs disease is associated with alterations in affective and sensorimotor striatal networks
A subset of patients with Parkinsonâs disease (PD) experiences problems with impulse control, characterized by a loss of voluntary control over impulses, drives, or temptations regarding excessive hedonic behavior. The present study aimed to better understand the neural basis of such impulse control disorders (ICDs) in PD. We collected resting-state functional connectivity and structural MRI data from 21 PD patients with ICDs and 30 patients without such disorders. To assess impulsivity, all patients completed the Barratt Impulsiveness Scale and performed an information-gathering task. MRI results demonstrated substantial differences in neural characteristics between PD patients with and without ICDs. Results showed that impulsivity was linked to alterations in affective basal ganglia circuitries. Specifically, reduced frontalâstriatal connectivity and GPe volume were associated with more impulsivity. We suggest that these changes affect decision making and result in a preference for risky or inappropriate actions. Results further showed that impulsivity was linked to alterations in sensorimotor striatal networks. Enhanced connectivity within this network and larger putamen volume were associated with more impulsivity. We propose that these changes affect sensorimotor processing such that patients have a greater propensity to act. Our findings suggest that the two mechanisms jointly contribute to impulsive behaviors in PD
HDQLIFE and neuroâQoL physical function measures: Responsiveness in persons with huntingtonâs disease
BackgroundHuntingtonâs disease (HD) is a neurological disorder that causes severe motor symptoms that adversely impact healthârelated quality of life. Patientâreported physical function outcome measures in HD have shown crossâsectional evidence of validity, but responsiveness has not yet been assessed.ObjectivesThis study evaluates the responsiveness of the Huntington Disease HealthâRelated Quality of Life (HDQLIFE) and the Quality of Life in Neurological Disorders (NeuroâQoL) physical function measures in persons with HD.MethodsA total of 347 participants completed baseline and at least 1 followâup (12âmonth and 24âmonth) measure (HDQLIFE Chorea, HDQLIFE Swallowing Difficulties, HDQLIFE Speech Difficulties, NeuroâQoL Upper Extremity Function, and/or NeuroâQoL Lower Extremity Function). Of the participants that completed the baseline assessment, 338 (90.9%) completed the 12âmonth assessment, and 293 (78.8%) completed the 24âmonth assessment. Standardized response means and general linear models evaluated whether the physical function measures were responsive to selfâreported and clinicianârated change over time.ResultsSmall to moderate effect sizes for the standardized response means supported 12âmonth and 24âmonth responsiveness of the HDQLIFE and NeuroâQoL measures for those with either selfâreported or clinicianârated declines in function. General linear models supported 12âmonth and 24âmonth responsiveness for all HRQOL measures relative to selfâreported declines in health, but generally only 24âmonth responsiveness was supported relative to clinicianârated declines in function.ConclusionsLongitudinal analyses indicate that the HDQLIFE and the NeuroâQoL physical function measures are sensitive to change over time in individuals with HD. Thus, these scales exhibit evidence of responsiveness and may be useful outcome measures in future clinical trials. © 2019 International Parkinson and Movement Disorder SocietyPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154235/1/mds27908_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154235/2/mds27908.pd
Agreement Between Clinician-Rated Versus Patient-Reported Outcomes in Huntington Disease
BACKGROUND: Clinician-rated measures of functioning are often used as primary endpoints in clinical trials and other behavioral research in Huntington disease. As study costs for clinician-rated assessments are not always feasible, there is a question of whether patient self-report of commonly used clinician-rated measures may serve as acceptable alternatives in low risk behavioral trials.
AIM: The purpose of this paper was to determine the level of agreement between self-report and clinician-ratings of commonly used functional assessment measures in Huntington disease.
DESIGN: 486 participants with premanifest or manifest Huntington disease were examined. Total Functional Capacity, Functional Assessment, and Independence Scale assessments from the Unified Huntington Disease Rating scale were completed by clinicians; a self-report version was also completed by individuals with Huntington disease. Cronbach\u27s α was used to examine internal consistency, one-way analysis of variance was used to examine group differences, and paired t tests, kappa agreement coefficients, and intra-class correlations were calculated to determine agreement between raters.
RESULTS: Internal consistency for self-reported ratings of functional capacity and ability were good. There were significant differences between those with premanifest, early-, and late-stage disease; those with later-stage disease reported less ability and independence than the other clinical groups. Although self-report ratings were not a perfect match with associated clinician-rated measures, differences were small. Cutoffs for achieving specified levels of agreement are provided.
CONCLUSIONS: Depending on the acceptable margin of error in a study, self-reported administration of these functional assessments may be appropriate when clinician-related assessments are not feasible
The pill questionnaire in a nondemented Parkinson's disease population
We assessed the Pill Questionnaire as a screen for mild cognitive impairment in nondemented Parkinson's disease patients. The relationship between ability to remember medications for Parkinson's disease in the Pill Questionnaire, mild cognitive impairment, and deficits on neuropsychological tests performed 2â3 weeks later blind to Pill Questionnaire results was assessed in movement disorders clinic patients. In 109 subjects, inaccurate medication reporting on the Pill Questionnaire was associated with lower scores on the Montreal Cognitive Assessment, Scales for Outcomes in Parkinson's DiseaseâCognition and with deficits in memory, attention, executive functionâinhibitory control, processing speed, visuospatial function, and language. Inaccurate medication reporting was also associated with an adjusted odds ratio of 2.4 (95% CI, 0.91â5.88; P = .06) for mild cognitive impairment, with a specificity of 80% and sensitivity of 41%. The Pill Questionnaire is neither sensitive nor specific enough to be used as the sole screening or diagnostic tool for mild cognitive impairment. However, inaccurate medication reporting is associated with deficits spanning many cognitive domains and should alert a clinician to a higher likelihood of cognitive impairment. © 2012 Movement Disorder SocietyPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/93736/1/25124_ftp.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/93736/2/MDS_25124_sm_SuppTables.pd
Galaxy and Mass Assembly (GAMA): merging galaxies and their properties
We derive the close pair fractions and volume merger rates for galaxies in the Galaxy and Mass Assembly (GAMA) survey with â23 < Mr < â17 (ΩM = 0.27, ΩΠ= 0.73, H0 = 100 km sâ1 Mpcâ1) at 0.01 < z < 0.22 (look-back time of <2 Gyr). The merger fraction is approximately 1.5 per cent Gyrâ1 at all luminosities (assuming 50 per cent of pairs merge) and the volume merger rate is â3.5 Ă 10â4 Mpcâ3 Gyrâ1. We examine how the merger rate varies by luminosity and morphology. Dry mergers (between red/spheroidal galaxies) are found to be uncommon and to decrease with decreasing luminosity. Fainter mergers are wet, between blue/discy galaxies. Damp mergers (one of each type) follow the average of dry and wet mergers. In the brighter luminosity bin (â23 < Mr < â20), the merger rate evolution is flat, irrespective of colour or morphology, out to z ⌠0.2. The makeup of the merging population does not appear to change over this redshift range. Galaxy growth by major mergers appears comparatively unimportant and dry mergers are unlikely to be significant in the buildup of the red sequence over the past 2 Gyr. We compare the colour, morphology, environmental density and degree of activity (BPT class, Baldwin, Phillips & Terlevich) of galaxies in pairs to those of more isolated objects in the same volume. Galaxies in close pairs tend to be both redder and slightly more spheroid dominated than the comparison sample. We suggest that this may be due to âharassmentâ in multiple previous passes prior to the current close interaction. Galaxy pairs do not appear to prefer significantly denser environments. There is no evidence of an enhancement in the AGN fraction in pairs, compared to other galaxies in the same volume
Interference filters as nonlinear decision-making elements for three-spot pattern recognition and associative memories
Simple patterns consisting of three spots (V and Î) have been recognized by dividing, shifting, and recombining
beams onto bistable ZnS interference filters. This experiment demonstrates AND-gate operation,
cascading, and a moderate amount of parallelism, but a laser power of several watts was required and the
response times were several milliseconds. An associative memory for fingerprint identification has been
constructed using a VanderLugt correlator and an interference filter as a reflective thresholding device
Dorsal subthalamic deep brain stimulation improves pain in Parkinson's disease
IntroductionInconsistent effects of subthalamic deep brain stimulation (STN DBS) on pain, a common non-motor symptom of Parkinson's disease (PD), may be due to variations in active contact location relative to some pain-reducing locus of stimulation. This study models and compares the loci of maximal effect for pain reduction and motor improvement in STN DBS.MethodsWe measured Movement Disorder Society Unified PD Rating Scale (MDS-UPDRS) Part I pain score (item-9), and MDS-UPDRS Part III motor score, preoperatively and 6â12 months after STN DBS. An ordinary least-squares regression model was used to examine active contact location as a predictor of follow-up pain score while controlling for baseline pain, age, dopaminergic medication, and motor improvement. An atlas-independent isotropic electric field model was applied to distinguish sites of maximally effective stimulation for pain and motor improvement.ResultsIn 74 PD patients, mean pain score significantly improved after STN DBS (pâ=â0.01). In a regression model, more dorsal active contact location was the only significant predictor of pain improvement (R2â=â0.17, pâ=â0.03). The stimulation locus for maximal pain improvement was lateral, anterior, and dorsal to that for maximal motor improvement.ConclusionSTN stimulation, dorsal to the site of optimal motor improvement, improves pain. This region contains the zona incerta, which is known to modulate pain in humans, and may explain this observation
A randomized, double-blind, placebo-controlled trial of coenzyme Q10 in Huntington disease
Objective: To test the hypothesis that chronic treatment of early-stage Huntington disease (HD) with high-dose coenzyme Q10 (CoQ) will slow the progressive functional decline of HD.
Methods: We performed a multicenter randomized, double-blind, placebo-controlled trial. Patients with early-stage HD (n = 609) were enrolled at 48 sites in the United States, Canada, and Australia from 2008 to 2012. Patients were randomized to receive either CoQ 2,400 mg/d or matching placebo, then followed for 60 months. The primary outcome variable was the change from baseline to month 60 in Total Functional Capacity score (for patients who survived) combined with time to death (for patients who died) analyzed using a joint-rank analysis approach.
Results: An interim analysis for futility revealed a conditional power of <5% for the primary analysis, prompting premature conclusion in July 2014. No statistically significant differences were seen between treatment groups for the primary or secondary outcome measures. CoQ was generally safe and well-tolerated throughout the study.
Conclusions: These data do not justify use of CoQ as a treatment to slow functional decline in HD
Antidepressants and Breast and Ovarian Cancer Risk: A Review of the Literature and Researchers' Financial Associations with Industry
BACKGROUND: Antidepressant (AD) use has been purported to increase the risk of breast and ovarian cancer, although both epidemiological and pre-clinical studies have reported mixed results. Previous studies in a variety of biomedical fields have found that financial ties to drug companies are associated with favorable study conclusions. METHODS AND FINDINGS: We searched English-language articles in MEDLINE, PsychINFO, the Science Citations Index and the Cochrane Central Register of Controlled Clinical Trials (through November 2010). A total of 61 articles that assessed the relationship between breast and ovarian cancer and AD use and articles that examined the effect of ADs on cell growth were included. Multi-modal screening techniques were used to investigate researchers' financial ties with industry. A random effects meta-analysis was used to pool the findings from the epidemiological literature. Thirty-three percent (20/61) of the studies reported a positive association between ADs and cancer. Sixty-seven percent (41/61) of the studies reported no association or antiproliferative effect. The pooled odds ratio for the association between AD use and breast/ovarian cancer in the epidemiologic studies was 1.11 (95% CI, 1.03-1.20). Researchers with industry affiliations were significantly less likely than researchers without those ties to conclude that ADs increase the risk of breast or ovarian cancer. (0/15 [0%] vs 20/46 [43.5%] (Fisher's Exact test Pâ=â0.0012). CONCLUSIONS: Both the pre-clinical and clinical data are mixed in terms of showing an association between AD use and breast and ovarian cancer. The possibility that ADs may exhibit a bi-phasic effect, whereby short-term use and/or low dose antidepressants may increase the risk of breast and ovarian cancer, warrants further investigation. Industry affiliations were significantly associated with negative conclusions regarding cancer risk. The findings have implications in light of the 2009 USPSTF guidelines for breast cancer screening and for the informed consent process
Synergistic study of a Danshen (Salvia Miltiorrhizae Radix et Rhizoma) and Sanqi (Notoginseng Radix et Rhizoma) combination on cell survival in EA.hy926 cells
Background: This study investigated the protective effects of the Danshen (DS) and Sanqi (SQ) herb pair on cell survival in the human cardiovascular endothelial (EA.hy926) cell line exposed to injury.
Methods: Nine combination ratios of Danshen-Sanqi extracts (DS-SQ) were screened for their protective effects in the EA.hy926 cell line against two different cellular impairments induced by DL-homocysteine (Hcy) â adenosine (Ado) â tumour necrosis factors (TNF) and oxidative stress (H2O2), respectively. The type of interaction (synergistic, antagonistic, additive) between DS and SQ was analysed using a combination index (CI) model. The effects of key bioactive compounds from DS and SQ were tested using the same models. The compound from each herb that demonstrated the most potent activity in cell viability was combined to evaluate their synergistic/antagonistic interaction using CI.
Results: DS-SQ ratios of 6:4 (50â300âÎŒg/mL) produced synergistic effects (CIâ<â1) in restoring cell viability, reducing lactate dehydrogenase (LDH) leakage and caspase-3 expressions against Hcy-Ado-TNF. Additionally, DS-SQ 6:4 (50â150âÎŒg/mL) was found to synergistically protect endothelial cells from impaired cellular injury induced by oxidative damage (H2O2) by restoring reduced cell viability and inhibiting excessive expression of reactive oxygen species (ROS). In particular, the combination of salvianolic acid A (SA) and ginsenoside Rb1 (Rb1) at 4:6 (1â150âÎŒM) showed synergistic effects in preventing cytotoxic effects caused by Hcy-Ado-TNF (CIâ<â1). This simplified combination also demonstrated synergistic effects on H2O2-induced oxidative damage on EA.hy926 cells.
Conclusions: This study provides scientific evidence to support the traditional use of the DS-SQ combination on protecting endothelial cells through their synergistic interactions
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