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1.
Biomed Opt Express ; 15(3): 1393-1407, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38495729

RESUMEN

Prism field expansion is a common treatment for patients with peripheral field loss, shifting images from the blind field into the seeing field. The shifted image originates from a new viewpoint translated and rotated from the original viewpoint by the prism. To understand such viewpoint changes, we simulated two field expansion methods in virtual reality: 1) angular (i.e., rotational) field expansion and 2) linear field expansion via image crop-and-shift. Changes to object locations, sizes, and optic flow patterns by those methods were demonstrated and analyzed in both static and dynamic conditions, which may affect navigation with such field expansion devices.

2.
Opt Express ; 32(2): 2631-2643, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38297787

RESUMEN

Among various specifications of near eye display (NED) devices, a compact formfactor is essential for comfortable user experience but also the hardest one to accomplish due to the slowest progresses. A pinhole/pinlight array based light-field (LF) technique is considered as one of the candidates to achieve that goal without thicker and heavier refractive optics. Despite those promising advantages, however, there are critical issues, such as dark spots and contrast distortion, which degrade the image quality because of the vulnerability of the LF retinal image when the observer's eye pupil size changes. Regardless of previous attempts to overcome those artifacts, it was impossible to resolve both issues due to their trade-off relation. In this paper, in order to resolve them simultaneously, we propose a concept of multiplexed retinal projections to integrate the LF retinal image through rotating transitions of refined and modulated elemental images for robust compensation of eye pupil variance with improved conservation of contrast distribution. Experimental demonstrations and quantitative analysis are also provided to verify the principle.


Asunto(s)
Pupila , Retina , Refracción Ocular , Óptica y Fotónica , Estimulación Luminosa
3.
Artículo en Inglés | MEDLINE | ID: mdl-38200400

RESUMEN

Stigmasterol, a plant-derived sterol, sharing structural similarity with cholesterol, has demonstrated anti-osteoarthritis (OA) properties, attributed to its antioxidant and anti-inflammatory capabilities. Given that OA often arises in weight bearing or overused joints, prolonged localized treatment effectively targets inflammatory aspects of the disease. This research explored the impact of stigmasterol-loaded nanoparticles delivered via intra-articular injections in an OA rat model. Employing mesoporous silica nanomaterials (MSNs) combined with ß-cyclodextrin (ß-CD) as a vehicle, stigmasterol was loaded in conjunction with tannic acid, forming stigmasterol/ß-CD-MSNs to facilitate a sustained stigmasterol release. The study employed RAW 264.7 cells to examine the in vitro cytotoxicity and anti-inflammatory effect of stigmasterol/ß-CD-MSNs. For in vivo experimentation, we used healthy control rats and monosodium iodoacetate (MIA)-induced OA rats, separated into five groups, varying the injection substances. In vitro findings indicated that stigmasterol/ß-CD-MSNs suppressed the mRNA expression of key pro-inflammatory mediators such as interleukin-6, tumor necrosis factor-α, and matrix metalloproteinase-3 in a dose-dependent manner. In vivo experiments revealed a substantial decrease in the mRNA levels of pro-inflammatory factors in the stigmasterol(50 µg)/ß-CD-MSN group compared to the others. Macroscopic, radiographic, and histological evaluations established that intra-articular injections of stigmasterol/ß-CD-MSNs inhibited cartilage degeneration and subchondral bone deterioration. Therefore, in a chemically induced OA rat model, intra-articular stigmasterol delivery was associated with reduction in both local and systemic inflammatory responses, alongside a slowdown in joint degradation and arthritic progression.

4.
Sci Rep ; 13(1): 20199, 2023 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-37980436

RESUMEN

Recent head-mounted displays and smart glasses use vision multiplexing, an optical approach where two or more views are superimposed on each other. In vision multiplexing, augmented information is presented over an observer's natural field of view, providing field expansion and critical information during mobility situations like walking and driving. Yet despite its utility, vision multiplexing may produce visual rivalry, a phenomenon where perception alternates between the augmented information and the background scene for seconds at a time. To investigate, we compared the effect of different peripheral vision multiplexing configurations (unilateral opaque, unilateral see-through and bilateral see-through) on the detection of augmented information, incorporating at the same time real-world characteristics (target eccentricity, depth condition, and gaze movement) for a more realistic assessment. Results showed a persistently lower target detection rate in unilateral configurations than the bilateral configuration, suggesting a larger effect of binocular rivalry on target visibility. Nevertheless, this effect does become attenuated when more naturalistic elements are incorporated, and we discuss recommendations for vision multiplexing design and possible avenues for further research.


Asunto(s)
Gafas Inteligentes , Visión Binocular , Percepción Visual , Movimiento
5.
Optom Vis Sci ; 100(8): 515-529, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37499041

RESUMEN

SIGNIFICANCE: Veridical depictions of scene appearance with scotomas allow better understanding of the impact of field loss and may improve the development and implementation of rehabilitation. Explanation and depiction of the invisibility of scotoma may lead to patients' understanding and thus better compliance with related treatments. PURPOSE: Simulations of perception with scotomas guide training, patient education, and rehabilitation research. Most simulations incorrectly depict scotomas as black patches, although the scotomas and the missing contents are usually invisible to patients. We present a novel approach to capture the reported appearance of scenes with scotomas. METHODS: We applied a content-aware image resizing algorithm to carve out the content elided under the scotomas. With video sequences, we show how and why eye movements fail to increase the visibility of the carved scotomas. RESULTS: Numerous effects, reported by patients, emerge naturally from the scotoma carving. Carving-eliminated scotomas over natural images are barely visible, despite causing substantial distortions. Low resolution and contrast sensitivity at farther eccentricities and saccadic blur reduce the visibility of the distortions. In a walking scenario, static objects moving smoothly to the periphery disappear into and then reemerge out of peripheral scotomas, invisibly. CONCLUSIONS: Scotoma carving provides a viable hypothetical simulation of vision with scotomas due to loss of neurons at the retinal ganglion cell level and higher. As a hypothesis, it generates predictions that lend themselves to future clinical testing. The different effects of scotomas due to loss of photoreceptors are left for follow-up work.


Asunto(s)
Escotoma , Campos Visuales , Humanos , Escotoma/diagnóstico , Escotoma/etiología , Movimientos Oculares , Movimientos Sacádicos , Sensibilidad de Contraste
6.
Clin Rheumatol ; 42(10): 2799-2809, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37369873

RESUMEN

INTRODUCTION/OBJECTIVES: This study aimed to identify differentially expressed genes (DEGs) of systemic lupus erythematosus (SLE) using gene expression-based computational methodologies to analyze disease-immune interactions, which affect the development and progression of SLE. METHOD: Twenty-six patients with SLE and 46 healthy controls were selected from the Gene Expression Omnibus (GEO) database. The significantly enriched immune and virus-related gene lists were computed and visualized by using the DEGs from the gene set enrichment analysis (GSEA). Quantification of 38 immune cells was performed in determining the impact of immune cells on the virus mediated immunity in SLE by using ImmQuant algorithm. RESULTS: Thirty-nine upregulated and 57 downregulated were identified in SLE patient compared to the healthy controls. Upregulated genes were significantly implicated in Gene Ontology gene sets as cytokine mediated signaling, secretion, and exocytosis in immune response pathways in 26 female SLE patients. In addition, these genes were enriched in hepatitis C, influenza A, measles, Epstein-Barr virus, and herpes simplex virus 1 infection in Kyoto Encyclopedia of Genes and Genomes pathways. Especially, FCGR1A, IRF7, OAS2, CAMP, MX1, OAS3, OAS1, DEFA3, ISG15, and RSAD2 were involved in virus mediated SLE mechanism, and the expression for OAS1, OAS2, and IRF7 was closely associated with the quantities of colony forming unit-monocyte and colony forming unit-granulocyte. CONCLUSIONS: Identifying virus-mediated SLE genes and quantifies of immune cells were used to understand the pathological process and perform early diagnosis of female SLE, and will lead to clinical tools for treating SLE in patients. Key Points • Using gene expression-based computational methodologies, the 57 immune and viral genes were significantly upregulated in 26 SLE patients. • The identified three key  viral genes such as OAS1, OAS2, and IF7 were closely associated with colony-forming unit-monocytes and colony-forming unit-granulocytes, which affect the virus mediated immunity in SLE. • The viral genes and quantifies of immune cells are useful in understanding pathogenesis of SLE, and this will provide clinical strategies of potential treatment choices in SLE patients.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Lupus Eritematoso Sistémico , Humanos , Femenino , Autoinmunidad , Herpesvirus Humano 4 , Citocinas
7.
Healthcare (Basel) ; 11(10)2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37239687

RESUMEN

Rheumatoid arthritis (RA) includes musculoskeletal symptoms that lead to disuse atrophy of muscles and changes in body composition. Musculoskeletal symptoms and loss of physical function may be associated with sarcopenia, which is characterized by muscle loss. This study aimed to investigate the prevalence of sarcopenia and its association with RA in a Korean population. We analyzed nationwide data from the Korea National Health and Nutrition Examination Survey of 7389 men and 9798 women. Binomial logistic regression models were used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) for sarcopenia prevalence in participants with RA. The prevalence of sarcopenia was 23.0% in men, 25.0% in women, 61.5% in men with RA, 32.3% in women with RA, 22.8% in men without RA, and 24.9% in women without RA. After adjusting for potential confounding variables, the prevalence of sarcopenia was higher in men with RA than in men without RA (OR, 3.11; 95% CI, 1.29-7.46), but this difference was not observed in women. In subgroup analysis which was stratified by age (age under 40, age between 40 and 59, age over 60), the OR for sarcopenia was higher in men with age over 60 years (OR, 4.12; 95% CI, 1.48-11.44) and women with age between 40 and 59 (OR, 2.29; 95% CI, 1.05-5.00). The prevalence of sarcopenia was higher in Korean men with RA and women with RA in middle age, suggesting the management of muscle loss will be needed, especially in Koreans with RA.

8.
Biomed Opt Express ; 14(5): 2352-2364, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37206143

RESUMEN

Oblique Fresnel peripheral prisms have been used for field expansion in homonymous hemianopia mobility such as walking and driving. However, limited field expansion, low image quality, and small eye scanning range limit their effectiveness. We developed a new oblique multi-periscopic prism using a cascade of rotated half-penta prisms, which provides 42° horizontal field expansion along with 18° vertical shift, high image quality, and wider eye scanning range. Feasibility and performance of a prototype using 3D-printed module are demonstrated by raytracing, photographic depiction, and Goldmann perimetry with patients with homonymous hemianopia.

9.
Artículo en Inglés | MEDLINE | ID: mdl-36970500

RESUMEN

Visual confusion occurs when two dissimilar images are superimposed onto the same retinal location. In the context of wearable displays, it can be used to provide multiple sources of information to users on top of the real-world scene. While useful, visual confusion may cause visual rivalry that can suppress one of the sources. If two different images are projected to each eye (i.e., monocular displays), it provokes binocular rivalry wherein visual perception intermittently switches between the two images. When a semi-transparent image is superimposed (i.e., see-through displays), monocular rivalry results, causing perceptual alternations between the foreground and the background images. Here, we investigated how these rivalries influence the visibility of the peripheral target using three configurations of wearable displays (i.e., monocular opaque, monocular see-through, and binocular see-through) with three eye movement conditions (i.e., saccades, smooth pursuit, and central fixation). Using the HTC VIVE Eye Pro headset, subjects viewed a forward vection of a 3D corridor with a horizontally moving vertical grating at 10° above the center fixation. During each trial (~1 min), subjects followed a fixation cross that varied in location to induce eye movements and simultaneously reported whether the peripheral target was visible. Results showed that the binocular display had significantly higher target visibility than both monocular displays, and the monocular see-through display had the lowest target visibility. Target visibility was also higher when eye movements were executed, suggesting that the effects of rivalry are attenuated by eye movements and binocular see-through displays.

10.
Artículo en Inglés | MEDLINE | ID: mdl-36970501

RESUMEN

Detecting and avoiding collisions during walking is critical for safe mobility. To determine the effectiveness of clinical interventions, a realistic objective outcome measure is needed. A real-world obstacle course with moving hazards has numerous limitations (e.g., safety concerns of physical collision, inability to control events, maintaining event consistency, and event randomization). Virtual reality (VR) platforms may overcome such limitations. We developed a VR walking collision detection test using a standalone head-mounted display (HMD, Meta Quest 2) with the Unity 3D engine to enable subjects' physical walking within a VR environment (i.e., a busy shopping mall). The performance measures focus on the detection and avoidance of potential collisions, where a pedestrian may (or may not) walks toward a collision with the subject, while various non-colliding pedestrians are presented simultaneously. The physical space required for the system was minimized. During the development, we addressed expected and unexpected hurdles, such as mismatch of visual perception of VR space, limited field of view (FOV) afforded by the HMD, design of pedestrian paths, design of the subject task, handling of subject's response (detection or avoidance behavior), use of mixed reality (MR) for walking path calibration. We report the initial implementation of the HMD VR walking collision detection and avoidance scenarios that showed promising potential as clinical outcome measures.

11.
J Hand Ther ; 36(3): 706-712, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36914488

RESUMEN

BACKGROUND: Paraffin bath therapy is noninvasive and is widely used in various hand diseases. Paraffin bath therapy is easy to use, has fewer side effects, and can be applied to various diseases with different etiologies. However, there are few large-scale studies of paraffin bath therapy, and there is insufficient evidence of its efficacy. PURPOSE: The purpose of the study was to investigate the effectiveness of paraffin bath therapy for pain relief and functional improvement in various hand diseases through a meta-analysis. STUDY DESIGN: Systematic review and meta-analysis of randomized controlled trials. METHODS: We searched for studies using PubMed and Embase. Eligible studies were selected based on the following criteria: (1) patients with any diseases of the hand; (2) comparison between paraffin bath therapy and no paraffin bath therapy; and (3) sufficient data on changes in the visual analog scale (VAS) score, grip strength, pulp-to-pulp pinch strength, or Austrian Canadian (AUSCAN) Osteoarthritis Hand index before and after paraffin bath therapy. Forest plots were drawn to visualize the overall effect. Jadad scale score, I2 statistics, and subgroup analyses were used to assess the risk of bias. RESULTS: A total of five studies included 153 patients who were treated and 142 who were not treated with paraffin bath therapy. The VAS were measured in all 295 patients included in the study, while the AUSCAN index was measured in the 105 patients with osteoarthritis. Paraffin bath therapy significantly reduced the VAS scores (mean difference [MD], -1.27; 95% confidence interval [CI] -1.93 to -0.60). In osteoarthritis, paraffin bath therapy significantly improved grip and pinch strength (MD -2.53; 95% CI 0.71-4.34; MD 0.77; 95% CI 0.71-0.83) and reduced the VAS and AUSCAN scores (MD -2.61; 95% CI -3.07 to -2.14; MD -5.02; 95% CI -8.95 to -1.09). DISCUSSION: Paraffin bath therapy significantly reduced the VAS and AUSCAN scores, and improved grip and pinch strength in patients with various hand diseases. CONCLUSIONS: Paraffin bath therapy is effective for alleviating pain and improving function in hand diseases, thereby improving quality of life. However, owing to the small number of patients included in the study and its heterogeneity, a further large-scale, well-structured study is needed.

12.
Cartilage ; 13(1): 19476035211069250, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35118894

RESUMEN

OBJECTIVE: Rebamipide has antioxidant effects and is a drug with a local rather than systemic mechanism of action. Oxidative stress and inflammation in chondrocytes are the major factors contributing to the development and progression of osteoarthritis (OA). Since OA is mainly developed in weight bearing or overused joints, the locally sustained therapy is effective for targeting inflammatory component of OA. We investigated the effects of intra-articular injection of rebamipide loaded nanoparticles (NPs) in OA rat model. DESIGN: We fabricated rebamipide-loaded methoxy poly(ethylene glycol)-b-poly(D,L-lactide) (mPEG-PDLLA) and poly(D, L-lactide-co-glycolide) (PLGA) NPs that allow the sustained release of rebamipide. In vitro, chondrocytes from rat were used to investigate the cytotoxicity and anti-inflammatory effect of rebamipide-loaded NPs. In vivo, monosodium iodoacetate (MIA)-induced OA rats were divided into 7 groups, consisting of healthy control rats and rats injected with MIA alone or in combination with NPs, rebamipide (1 mg)/NPs, rebamipide (10 mg)/NPs, rebamipide (10 mg) solution, or oral administration. RESULTS: In vitro, rebamipide/NPs dose-dependently suppressed the mRNA levels of pro-inflammatory mediators, including interleukin (IL)-1ß, IL-6, tumor necrosis factor-α, matrix metalloproteinase (MMP)-3, MMP-13, and cyclo-oxygenase-2. In vivo, the mRNA levels of pro-inflammatory components most markedly decreased in the intra-articularly injected rebamipide (10 mg)/NP group compared to other groups. Macroscopic, radiographic, and histological evaluations showed that the intra-articular injection of rebamipide/NPs inhibited cartilage degeneration more than rebamipide solution or rebamipide administration. CONCLUSIONS: Using a chemically induced rat model of OA, intra-articular delivery of rebamipide was associated with decreased local and systemic inflammatory response decreased joint degradation and arthritic progression.


Asunto(s)
Cartílago Articular , Nanopartículas , Osteoartritis , Alanina/análogos & derivados , Animales , Cartílago Articular/patología , Progresión de la Enfermedad , Inyecciones Intraarticulares , Osteoartritis/metabolismo , Proyectos Piloto , Quinolonas , ARN Mensajero/metabolismo , Ratas
13.
J Int Med Res ; 50(1): 3000605221075220, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35086377

RESUMEN

OBJECTIVE: To determine whether polymorphisms of interleukin 12B (IL12B) and IL23 receptor genes (IL23R) confer susceptibility to systemic lupus erythematosus (SLE). METHODS: A meta-analysis was conducted to analyze the associations between SLE and IL12B rs3212227 and rs17860508 and IL23R rs7517847, rs10489629, rs10889677, rs1004819, rs11209026, rs11209032, rs1343151, and rs1884444 polymorphisms using allele contrast, dominant, recessive, heterozygote, and homozygote models. Ten studies involving 1989 patients with SLE and 2394 controls were considered for the meta-analysis. RESULTS: The meta-analysis using the homozygote model revealed that IL23R rs10889677 was significantly associated with SLE susceptibility in the overall population (AA vs. CC) (odds ratio = 0.70, 95% confidence interval = 0.50-0.98) but not in the Asian population. Other polymorphisms of IL12B and IL23R were not significantly associated with SLE protection. CONCLUSIONS: These findings suggest that the IL23R rs10889677 polymorphism confers SLE susceptibility to individuals of certain ethnicities. (Research Registry number: 1268).


Asunto(s)
Subunidad p40 de la Interleucina-12 , Lupus Eritematoso Sistémico , Pueblo Asiatico , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Humanos , Lupus Eritematoso Sistémico/genética , Polimorfismo de Nucleótido Simple/genética , Receptores de Interleucina/genética
14.
Minerva Pediatr (Torino) ; 74(1): 81-89, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-30511559

RESUMEN

INTRODUCTION: The aim of this review is to investigate IL-10 polymorphisms (-1082 G/A, -819 C/T, and -592 C/A) and their association with susceptibility to JIA. EVIDENCE ACQUISITION: A meta-analysis was conducted after database search for relevant articles (MEDLINE and EMBASE). EVIDENCE SYNTHESIS: A total of seven studies involving 1495 patients and 1670 controls were considered in the meta-analysis. There was no association between the IL-10 -1082 G/A, -819 C/T, and -592 C/A polymorphisms and JIA in allele contrast and any of the genetic models (allele contrast: odds ratio [OR] 0.90, 95% confidence interval [CI] 0.79-1.02, P=0.09; OR=0.97, 95% CI 0.83-1.13, P=0.68; OR=0.92, 95% CI 0.81-1.06, P=0.24, respectively). In subgroup analysis, none of the subtypes of JIA including systemic, rheumatoid factor (RF)-positive polyarticular, RF-negative polyarticular, and oligoarticular was not significantly associated with IL-10 polymorphism. Meta-analysis of the IL-10 haplotype revealed no association between GCC, ACC, and ATA haplotypes and JIA. CONCLUSIONS: This meta-analysis showed that IL-10 polymorphisms were not associated with risk of JIA.


Asunto(s)
Artritis Juvenil , Interleucina-10 , Artritis Juvenil/genética , Predisposición Genética a la Enfermedad , Haplotipos , Humanos , Interleucina-10/genética , Polimorfismo de Nucleótido Simple
15.
Minerva Pediatr (Torino) ; 74(2): 213-221, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-31692313

RESUMEN

INTRODUCTION: In juvenile idiopathic arthritis (JIA), interleukin (IL)-1, IL-6, and tumor necrosis factor-alpha (TNF-α) are associated with development and progression of JIA. We investigated whether IL-1, IL-6, and TNF-α polymorphisms were associated with susceptibility to JIA. EVIDENCE ACQUISITION: A meta-analysis was conducted on the associations between IL-1α-899 C/T, IL-1ß-511 C/T, IL-6-174 G/C, and TNF-α-308 G/A and -238 G/A polymorphisms, and JIA (PubMed and Embase). EVIDENCE SYNTHESIS: A total of 27 studies involving 4678 JIA patients and 7634 controls were considered in the meta-analysis. There was no association between the IL-1α-899 C/T, IL-1ß-511 C/T, IL-6-174 G/C, and TNF-α-308 G/A and -238 G/A polymorphisms, and JIA in allele contrast or any other genetic models. In subgroup analysis based on subtype, except for the dominant model of TNF-α-238 G/A, systemic JIA was not significantly associated with IL-6 and TNF-α polymorphisms. In Caucasians, the dominant and additive models of IL-1ß-511 C/T were significantly associated with JIA (odds ratio [OR] 1.48, 95% confidence interval [CI] 1.09-2.00, P=0.01; OR 1.46, 95% CI 1.05-2.03, P=0.02, respectively). CONCLUSIONS: This meta-analysis showed no association between IL-1, IL-6, and TNF-α polymorphisms, and JIA, but the TT genotype of IL-1ß -511 C/T was associated with higher prevalence of JIA in Caucasians.


Asunto(s)
Artritis Juvenil , Factor de Necrosis Tumoral alfa , Artritis Juvenil/genética , Predisposición Genética a la Enfermedad , Humanos , Interleucina-6/genética , Polimorfismo de Nucleótido Simple , Factor de Necrosis Tumoral alfa/genética
16.
Disabil Rehabil Assist Technol ; 17(8): 888-896, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-32997554

RESUMEN

PURPOSE: Visual sensory substitution devices (SSDs) convey visual information to a blind person through another sensory modality. Using a visual SSD in various daily activities requires training prior to use the device independently. Yet, there is limited literature about procedures and outcomes of the training conducted for preparing users for practical use of SSDs in daily activities. METHODS: We trained 29 blind adults (9 with congenital and 20 with acquired blindness) in the use of a commercially available electro-tactile SSD, BrainPort. We describe a structured training protocol adapted from the previous studies, responses of participants, and we present retrospective qualitative data on the progress of participants during the training. RESULTS: The length of the training was not a critical factor in reaching an advanced stage. Though performance in the first two sessions seems to be a good indicator of participants' ability to progress in the training protocol, there are large individual differences in how far and how fast each participant can progress in the training protocol. There are differences between congenital blind users and those blinded later in life. CONCLUSIONS: The information on the training progression would be of interest to researchers preparing studies, and to eye care professionals, who may advise patients to use SSDs.IMPLICATIONS FOR REHABILITATIONThere are large individual differences in how far and how fast each participant can learn to use a visual-to-tactile sensory substitution device for a variety of tasks.Recognition is mainly achieved through top-down processing with prior knowledge about the possible responses. Therefore, the generalizability is still questionable.Users develop different strategies in order to succeed in training tasks.


Asunto(s)
Personas con Daño Visual , Adulto , Ceguera , Humanos , Estudios Retrospectivos , Lengua , Tacto
17.
Optom Vis Sci ; 98(10): 1210-1226, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34629434

RESUMEN

SIGNIFICANCE: Photographic depiction helps to illustrate the primary and secondary field of view effects of low vision devices along with their utility to clinicians, patients, and caretakers. This technique may also be helpful for designers and researchers in improving the design and fitting of low vision devices. PURPOSE: The field of view through spectacles-mounted low vision devices has typically been evaluated using perimetry. However, the perimetric field diagram is different from the retinal image and often fails to represent the important aspects of the field of view and visual parameters. We developed a photographic depiction method to record and veridically show the field of view effects of these devices. METHODS: We used a 3D-printed holder to place spectacles-mounted devices at the same distance from the empirically determined reference point of the field of view in a camera lens (f = 16 mm) as they would be from an eye, when in use. The field of view effects of a bioptic telescope, a minifier (reverse telescope), and peripheral prisms were captured using a conventional camera, representing retinal images. The human eye pupil size (adjusting the F number: f/2.8 to f/8 and f/22 in the camera lens) and fitting parameters (pantoscopic tilt and back vertex distance) varied. RESULTS: Real-world indoor and outdoor walking and driving scenarios were depicted as retinal images illustrating the field of view through low vision devices, distinguishing optical and obscuration scotomas, and demonstrating secondary effects (spatial distortions, viewpoint changes, diplopia, spurious reflection, and multiplexing effects) not illustrated by perimetric field diagrams. CONCLUSIONS: Photographic depiction illustrates the primary and secondary field of view effects of the low vision devices. These images highlight the benefit and possible trade-offs of the low vision devices and may be beneficial in education and training.


Asunto(s)
Anteojos , Baja Visión , Humanos , Trastornos de la Visión , Visión Ocular , Pruebas del Campo Visual
18.
J Neural Eng ; 18(4)2021 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34359062

RESUMEN

Objective. The perception of individuals fitted with retinal prostheses is not fully understood, although several retinal implants have been tested and commercialized. Realistic simulations of perception with retinal implants would be useful for future development and evaluation of such systems.Approach.We implemented a retinal prosthetic vision simulation, including temporal features, which have not been previously simulated. In particular, the simulation included temporal aspects such as persistence and perceptual fading of phosphenes and the electrode activation rate.Main results.The simulated phosphene persistence showed an effective reduction in flickering at low electrode activation rates. Although persistence has a positive effect on static scenes, it smears dynamic scenes. Perceptual fading following continuous stimulation affects prosthetic vision of both static and dynamic scenes by making them disappear completely or partially. However, we showed that perceptual fading of a static stimulus might be countered by head-scanning motions, which together with the persistence revealed the contours of the faded object. We also showed that changing the image polarity may improve simulated prosthetic vision in the presence of persistence and perceptual fading.Significance.Temporal aspects have important roles in prosthetic vision, as illustrated by the simulations. Considering these aspects may improve the future design, the training with, and evaluation of retinal prostheses.


Asunto(s)
Fosfenos , Prótesis Visuales , Simulación por Computador , Humanos , Retina , Trastornos de la Visión
19.
Artículo en Inglés | MEDLINE | ID: mdl-34360173

RESUMEN

Coffee consumption is gradually increasing in Korea. As a result, interest in the relationship between coffee consumption and various diseases is growing. Several factors affect the development of rheumatoid arthritis (RA), and coffee consumption may be related. We conducted a nationwide cross-sectional study using data from the Korea National Health and Nutrition Examination Survey (2012-2016). A total of 12,465 eligible participants (4819 men and 7646 women) were included in the study. Participants with RA were defined as those who were diagnosed and currently being treated by physicians. Daily coffee consumption amounts were categorized as none, <1 cup, 1-2 cups, 2-3 cups, and ≥3 cups a day based on a self-report. A multivariable logistic regression model was employed, and we calculated the odds ratios (ORs) and 95% confidence intervals (CIs) for the odds of participants having RA with respect to coffee consumption. Compared to the no-coffee group, the ORs for RA in the <1 cup and 1-2 cups groups were 2.99 (95% CI 0.33-27.28) and 2.63 (95% CI 0.31-22.63) in men, respectively, and the ORs for RA for women in the <1 cup, 1-2 cups, 2-3 cups, and ≥3 cups groups were 0.62 (95% CI 0.31-1.26), 0.67 (95% CI 0.33-1.37), 1.08 (95% CI 0.35-3.36), and 1.43 (95% CI 0.25-8.36), respectively. Our study concludes, therefore, that daily coffee consumption is not related to the prevalence of RA in the general Korean population.


Asunto(s)
Artritis Reumatoide , Café , Artritis Reumatoide/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Encuestas Nutricionales , República de Corea/epidemiología , Factores de Riesgo
20.
Artículo en Inglés | MEDLINE | ID: mdl-34257685

RESUMEN

This study investigated the hypothesis that Portulaca oleracea L. exerts antiobesity and antidiabetic effects by evaluating blood lipid profiles, blood glucose control factors, protein expression of lipid metabolism, and insulin sensitivity improvement. Three groups of high-fat diet (HFD) induced obese C57BL/6 mice (n = 8) received treatment with low (5%; HFD + PO5%) or high (10%; HFD + PO10%) concentrations of P. oleracea powder for 12 weeks or no treatment (HFD) and were compared with each other and a fourth control group. Weight gain was reduced by 34% in the HFD + PO10% group compared to the HFD group. Moreover, the perirenal and epididymal fat contents in the HFD + PO10% group were 6.3-fold and 1.5-fold, respectively, lower than those in the HFD group. The atherogenic index (AI) and cardiac risk factor (CRF) results in the P. oleracea-treated groups were significantly lower than those in the HFD group. The homeostasis model assessment of insulin resistance (HOMA-IR) levels was lower in the HFD + PO10% group than in the HFD group. The protein expression levels of the proliferator-activated receptor (PPAR)-α, glucose transporter (GLUT) 4 and PPAR-γ were upregulated in the HFD + PO10% group compared to the HFD group. However, the protein expression levels of tumor necrosis factor (TNF)-α were lower in the P. oleracea-treated groups than in the HFD group. Our results demonstrate that P. oleracea powder could be effectively used to treat and prevent obesity and diabetes-associated diseases through suppression of weight gain and reduction in body fat and blood glucose levels.

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