295 research outputs found
Anodal transcranial direct current stimulation over S1 differentially modulates proprioceptive accuracy in young and old adults
Background: Proprioception is a prerequisite for successful motor control but declines throughout the lifespan. Brain stimulation techniques such as anodal transcranial direct current stimulation (a-tDCS) are capable of enhancing sensorimotor performance across different tasks and age groups. Despite such growing evidence for a restorative potential of tDCS, its impact on proprioceptive accuracy has not been studied in detail yet. Objective: This study investigated online effects of a-tDCS over S1 on proprioceptive accuracy in young (YA) and old healthy adults (OA). Methods: The effect of 15 min of a-tDCS vs. sham on proprioceptive accuracy was assessed in a cross-over, double blind experiment in both age groups. Performance changes were tested using an arm position matching task in a robotic environment. Electrical field (EF) strengths in the target area S1 and control areas were assessed based on individualized simulations. Results: a-tDCS elicited differential changes in proprioceptive accuracy and EF strengths in the two groups: while YA showed a slight improvement, OA exhibited a decrease in performance during a-tDCS. Stronger EF were induced in target S1 and control areas in the YA group. However, no relationship between EF strength and performance change was found. Conclusion: a-tDCS over S1 elicits opposing effects on proprioceptive accuracy as a function of age, a result that is important for future studies investigating the restorative potential of a-tDCS in healthy aging and in the rehabilitation of neurological diseases that occur at advanced age. Modeling approaches could help elucidate the relationship between tDCS protocols, brain structure and performance modulation
The Figure in Art: Selections from the Gettysburg College Collection
The Figure in Art: Selections from the Gettysburg College Collection is the second annual exhibition curated by students enrolled in the Art History Methods class. This exhibition is an exciting academic endeavor and provides an incredible opportunity for engaged learning, research, and curatorial experience. The eleven student curators are Diane Brennan, Rebecca Duffy, Kristy Garcia, Megan Haugh, Dakota Homsey, Molly Lindberg, Kathya Lopez, Kelly Maguire, Kylie McBride, Carolyn McBrady and Erica Schaumberg. Their research presents a multifaceted view of the representation of figures in various art forms from different periods and cultures.https://cupola.gettysburg.edu/artcatalogs/1017/thumbnail.jp
Is Household Air Pollution a Risk Factor for Eye Disease?
In developing countries, household air pollution (HAP) resulting from the inefficient burning of coal and biomass (wood, charcoal, animal dung and crop residues) for cooking and heating has been linked to a number of negative health outcomes, mostly notably respiratory diseases and cancers. While ocular irritation has been associated with HAP, there are sparse data on adverse ocular outcomes that may result from acute and chronic exposures. We consider that there is suggestive evidence, and biological plausibility, to hypothesize that HAP is associated with some of the major blinding, and painful, eye conditions seen worldwide. Further research on this environmental risk factor for eye diseases is warranted
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Vision-Related Quality of Life in Patients with Ocular Graft-versus-Host Disease
Objective
To assess the vision-related quality of life in a cohort of patients with ocular graft-versus-host disease (GVHD).
Design
Prospective study.
Participants
Eighty-four patients diagnosed with chronic ocular GVHD
Methods
We assessed the vision-related quality of life with the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25). The symptoms of ocular GVHD were assessed using the Ocular Surface Disease Index (OSDI) and Symptom Assessment in Dry Eye (SANDE) questionnaires.
Main outcome measures
We assessed vision-related quality of life with NEI-VFQ-25 and compared the scores obtained from patients with ocular GVHD to those from a healthy population. In the ocular GVHD population, we also evaluated the associations between the NEI-VFQ-25 and dry eye symptoms measured by OSDI and SANDE questionnaires, age, duration of disease, best-corrected visual acuity, corneal fluorescein staining, tear break-up time, and Schirmer test.
Results
The mean composite NEI-VFQ-25 score in patients with ocular GVHD was 76.5 ± 17. Compared to healthy subjects, ocular GVHD patients reported reduced scores on all NEI-VFQ-25 subscales (each P < 0.001) with exception of color vision (P = 0.11). The NEI-VFQ-25 composite scores significantly correlated with OSDI (R = −0.81, P < 0.001), SANDE (R = −0.56, P < 0.001), corneal fluorescein staining (R = −0.36, P = 0.001) and best-corrected visual acuity (R = −0.30, P = 0.004).
Conclusion
Patients with ocular GVHD experience measurable impairment of vision-related quality of life. This study highlights the impact of ocular GVHD on the vision-related quality of life, and hence the importance of comprehensive diagnosis and treatment of this condition
Clinical disorders affecting mesopic vision
Vision in the mesopic range is affected by a number of inherited and acquired clinical disorders. We review these conditions and summarize the historical background, describing the clinical characteristics alongside the genetic basis and molecular biological mechanisms giving rise to rod and cone dysfunction relevant to twilight vision. The current diagnostic gold standards for each disease are discussed and curative and symptomatic treatment strategies are summarized
National Outbreak of Acanthamoeba Keratitis Associated with Use of a Contact Lens Solution, United States
Premarket standardized testing for Acanthamoeba spp. is warranted
C2 and CFB Genes in Age-Related Maculopathy and Joint Action with CFH and LOC387715 Genes
Background: Age-related maculopathy (ARM) is a common cause of visual impairment in the elderly populations of industrialized countries and significantly affects the quality of life of those suffering from the disease. Variants within two genes, the complement factor H (CFH) and the poorly characterized LOC387715 (ARMS2), are widely recognized as ARM risk factors. CFH is important in regulation of the alternative complement pathway suggesting this pathway is involved in ARM pathogenesis. Two other complement pathway genes, the closely linked complement component receptor (C2) and complement factor B (CFB), were recently shown to harbor variants associated with ARM. Methods/Principal Findings: We investigated two SNPs in C2 and two in CFB in independent case-control and family cohorts of white subjects and found rs547154, an intronic SNP in C2, to be significantly associated with ARM in both our case-control (P-value 0.00007) and family data (P-value 0.00001). Logistic regression analysis suggested that accounting for the effect at this locus significantly (P-value 0.002) improves the fit of a genetic risk model of CFH and LOC387715 effects only. Modeling with the generalized multifactor dimensionality reduction method showed that adding C2 to the two-factor model of CFH and LOC387715 increases the sensitivity (from 63% to 73%). However, the balanced accuracy increases only from 71% to 72%, and the specificity decreases from 80% to 72%. Conclusions/Significance: C2/CFB significantly influences AMD susceptibility and although accounting for effects at this locus does not dramatically increase the overall accuracy of the genetic risk model, the improvement over the CFH-LOC387715 model is statistically significant. © 2008 Jakobsdottir et al
Analysis of copy number variation at DMBT1 and age-related macular degeneration
BACKGROUND:
DMBT1 is a gene that shows extensive copy number variation (CNV) that alters the number of bacteria-binding domains in the protein and has been shown to activate the complement pathway. It lies next to the ARMS2/HTRA1 genes in a region of chromosome 10q26, where single nucleotide variants have been strongly associated with age-related macular degeneration (AMD), the commonest cause of blindness in Western populations. Complement activation is thought to be a key factor in the pathogenesis of this condition. We sought to investigate whether DMBT1 CNV plays any role in the susceptibility to AMD.
METHODS:
We analysed long-range linkage disequilibrium of DMBT1 CNV1 and CNV2 with flanking single nucleotide polymorphisms (SNPs) using our previously published CNV and HapMap Phase 3 SNP data in the CEPH Europeans from Utah (CEU). We then typed a large cohort of 860 AMD patients and 419 examined age-matched controls for copy number at DMBT1 CNV1 and CNV2 and combined these data with copy numbers from a further 480 unexamined controls.
RESULTS:
We found weak linkage disequilibrium between DMBT1 CNV1 and CNV2 with the SNPs rs1474526 and rs714816 in the HTRA1/ARMS2 region. By directly analysing copy number variation, we found no evidence of association of CNV1 or CNV2 with AMD.
CONCLUSIONS:
We have shown that copy number variation at DMBT1 does not affect risk of developing age-related macular degeneration and can therefore be ruled out from future studies investigating the association of structural variation at 10q26 with AMD
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