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1.
Artículo en Inglés | MEDLINE | ID: mdl-37268825

RESUMEN

Recent research has proposed new approaches to investigate color vision in Old World Monkeys by measuring suprathreshold chromatic discrimination. In this study, we aimed to extend this approach to New World Monkeys with different color vision genotypes by examining their performance in chromatic discrimination tasks along different fixed chromatic saturation axes. Four tufted capuchin monkeys were included in the study, and their color vision genotypes were one classical protanope, one classical deuteranope, one non-classical protanope, and a normal trichromat. During the experiments, the monkeys were required to perform a chromatic discrimination task using pseudoisochromatic stimuli with varying target saturations of 0.06, 0.04, 0.03, and 0.02 u'v' units. The number of errors made by the monkeys along different chromatic axes was recorded, and their performance was quantified using the binomial probability of their hits during the tests. Our results showed that dichromatic monkeys made more errors near the color confusion lines associated with their specific color vision genotypes, while the trichromatic monkey did not demonstrate any systematic errors. At high chromatic saturation, the trichromatic monkey had significant hits in the chromatic axes around the 180° chromatic axis, whereas the dichromatic monkeys had errors in colors around the color confusion lines. At lower saturation, the performance of the dichromatic monkeys became more challenging to differentiate among the three types, but it was still distinct from that of the trichromatic monkey. In conclusion, our findings suggest that high saturation conditions can be used to identify the color vision dichromatic phenotype of capuchin monkeys, while low chromatic saturation conditions enable the distinction between trichromats and dichromats. These results extend the understanding of color vision in New World Monkeys and highlight the usefulness of suprathreshold chromatic discrimination measures in exploring color vision in non-human primates.


Asunto(s)
Visión de Colores , Animales , Percepción de Color/fisiología , Sapajus apella , Genotipo , Cebus/genética , Platirrinos , Color
2.
BMC Ophthalmol ; 24(1): 213, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38755573

RESUMEN

The inconsistency in terminology for Cortical Visual Impairment or Cerebral Visual Impairment presents challenges: (1) different levels of changes in visual pathway and other cerebral areas do not allow discrimination; (2) different visual and oculomotor aspects are not adequately considered. We open a debate to consider a more appropriate diagnosis.


Asunto(s)
Terminología como Asunto , Trastornos de la Visión , Humanos , Trastornos de la Visión/fisiopatología , Trastornos de la Visión/diagnóstico , Corteza Visual/fisiología , Vías Visuales/fisiopatología
3.
Int Ophthalmol ; 44(1): 127, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38466499

RESUMEN

PURPOSE: We aimed the develop and validate a computerized version of the MNREAD for the assessment of reading speed for children. METHODS: A computerized version of the MNREAD was built in Psykinematix software using the same parameters as the physical chart. We measured the reading velocity of 104 children (n = 44 of the 3rd grade; n = 60 of the 5th grade). Bland-Altaman analysis was used to quantify agreement between two chart measurements. RESULTS: Comparison between the 3rd and 5th-grade children for physical and computerized MNREAD versions showed statistical differences in Maximum Reading Speed (F = 2669.6; p < 0.001), Critical Print Size (F = 17.49; p < 0.001), and Reading Acuity (F = 14.19; p = 0.002) with huge effect size (η2 = 0.930). No differences were found between the versions within grades. Bland-Altman analysis showed 95% of the data points within ± 2 s of the mean difference, suggesting a similarity between versions of the MNREAD parameters. CONCLUSION: Our reading speed values for children in the 5th grade were higher than previous studies, suggesting a better quality of the assessment in the computerized version. Tolerance Limits were calculated as normality references for clinical purposes.


Asunto(s)
Lectura , Pruebas de Visión , Niño , Humanos , Agudeza Visual , Escolaridad , Programas Informáticos
4.
Vis Neurosci ; 39: E006, 2022 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-36226362

RESUMEN

Aging causes impairment of contrast sensitivity and chromatic discrimination, leading to changes in the perceptual interactions between color and luminance information. We aimed to investigate the influence of chromatic noise on luminance contrast thresholds in young and older adults. Forty participants were divided equally into Young (29.6 ± 6.3-year-old) and Elderly Groups (57.8 ± 6.6-year-old). They performed a luminance contrast discrimination task in the presence of chromatic noise maskers using a mosaic stimulus in a mosaic background. Four chromatic noise masking protocols were applied (protan, deutan, tritan, and no-noise protocols). We found that luminance contrast thresholds were significantly elevated by the addition of chromatic noise in both age groups (P < 0.05). In the Elderly group, but not the younger group, thresholds obtained in the tritan protocol were lower than those obtained from protan and deutan protocols (P < 0.05). For all protocols, the luminance contrast thresholds of elderly participants were higher than in young people (P < 0.01). Tritan chromatic noise was less effective in inhibiting luminance discrimination in elderly participants.


Asunto(s)
Percepción de Color , Sensibilidad de Contraste , Adolescente , Adulto , Anciano , Humanos , Persona de Mediana Edad , Ruido , Estimulación Luminosa/métodos , Umbral Sensorial , Visión Ocular , Adulto Joven
5.
J Vis ; 16(8): 13, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27299773

RESUMEN

When combined with the electroretinogram (ERG), the heterochromatic flicker photometry procedure allows an objective in vivo assessment of postreceptoral activity. Responses evoked at intermediate (approximately 12 Hz) and high (>30 Hz) temporal frequencies reflect the red-green cone opponent (possibly parvocellular) and the luminance (possibly magnocellular) responses, respectively. Previously, we found that cone-isolating stimuli at intermediate temporal frequencies elicited ERG responses with similar amplitudes and phases for different spatial arrangements of the stimuli, whereas response amplitudes at high temporal frequencies were positively correlated with stimulus size. The purpose of this study was to investigate whether the influence of stimulus size was confined to cone-isolating stimuli or whether it was a general feature of heterochromatic stimulation. Furthermore, we aimed to determine the smallest spatial extent for a significant response in the two postreceptoral mechanisms. Monocular ERGs were recorded to red-green counterphase modulated sinusoidal stimuli (mean luminance of 200 cd/m2) presented at 12 and 36 Hz at different stimulus sizes. At each stimulus condition, a series of ERGs were recorded with the red-contrast fraction (FR) [FR = CR/(CR + CR)] of the stimulus varying between 0.0 and 1.0. Response amplitudes at 36 Hz changed with FR for all subjects, exhibiting a V-shaped amplitude profile with a minimum close to the psychophysics-based isoluminance, where the ERG phase changed by 180°. As stimulus size decreased, the amplitudes to 36 Hz also decreased. In contrast, amplitudes and phases at 12 Hz generally were constant for all values of FR. These amplitudes were invariant to stimulus sizes larger than 10° but decreased with decreasing stimulus size below 10°. Phase also changed in this range. Thus, luminance pathway ERG responses (36 Hz) show direct dependency on stimulus size, whereas chromatic pathway responses (12 Hz) are independent of the stimulus size above 10°.


Asunto(s)
Percepción de Color/fisiología , Condicionamiento Psicológico/fisiología , Electrorretinografía/métodos , Células Fotorreceptoras Retinianas Conos/fisiología , Visión Binocular/fisiología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estimulación Luminosa
6.
Behav Brain Funct ; 10: 22, 2014 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-24961924

RESUMEN

INTRODUCTION: The aim of the present study was to evaluate color perception thresholds and relate them to the degree of motor impairment in children with spastic cerebral palsy (SCP). METHODS: Binocular and monocular chromaticity discrimination thresholds were estimated for the protan, deutan, and tritan color confusion axes in 43 SCP children aged 6-15 years who were classified as tetraplegic (n = 12), diplegic (n = 16), and hemiplegic (n = 15) without ophthalmological complaints. Motor impairment was rated according to the Gross Motor Function Classification System (GMFCS) in five levels of severity. RESULTS: Analysis of variance showed significantly reduced discrimination in tetraplegic children (p < 0.001) compared with the diplegic, hemiplegic, and control groups. We also found a positive correlation between chromaticity discrimination thresholds and GMFCS ratings in all of the groups. DISCUSSION: Chromaticity discrimination thresholds measured psychophysically were reduced for all three color confusion axis in tetraplegic children compared with normal children. Diplegic and hemiplegic children had similar results as normal children. The finding of a correlation between quantified motor impairment and color discrimination losses in SCP patients is a new observation that might help elucidate the causes of color perception loss in these patients. Visual information is essential for the rehabilitation of CP children. Knowledge of the degree of correlation between vision and motor impairment is valuable when planning a rehabilitation program.


Asunto(s)
Parálisis Cerebral/fisiopatología , Percepción de Color/fisiología , Destreza Motora/fisiología , Adolescente , Niño , Femenino , Humanos , Masculino , Umbral Sensorial/fisiología
7.
Doc Ophthalmol ; 129(2): 129-38, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24969135

RESUMEN

BACKGROUND: Electroretinographic measurement instruments allow the variation of several stimulation parameters enabling to study a wide range of retinal processes. The purpose of the present study was to measure human flicker electroretinograms (ERGs) varying temporal modulation, temporal frequency and mean luminance in the photopic and higher mesopic ranges where the change from cone to rod dominance occurs. METHODS: Fourteen healthy subjects (mean age = 31 ± 6) participated in this study. ERG recordings were performed with the RetiPort system (Roland Consult, Germany). The stimuli were ON and OFF sawtooth waves, square wave and sine wave. The temporal frequencies were 4 and 8 Hz. The mean luminance varied from 1 to 60 cd/m(2). RESULTS: The results confirmed the possibility to distinguish between rod- and cone-dominated retinal responses when using the flicker ERG at different temporal frequencies and luminances. We have also evaluated the responses at luminance levels at which the transition between rod- and cone-dominated responses occurs. This transition between rod- and cone-dominated flicker ERG responses is indicated by a significant change in the response characteristics between 4 and 8 cd/m(2) (between 200 and 400 phot Td). CONCLUSIONS: The findings on the transition between rod- and cone-dominated ERGs along with the demonstration of ERG responses to different temporal flicker modulations might be informative for the electrophysiologists when setting up the stimulus at mesopic and photopic luminance levels.


Asunto(s)
Visión de Colores/fisiología , Electrorretinografía , Visión Mesópica/fisiología , Retina/fisiología , Adulto , Femenino , Voluntarios Sanos , Humanos , Masculino , Estimulación Luminosa
8.
Turk Psikiyatri Derg ; 35(2): 156-161, 2024.
Artículo en Inglés, Turco | MEDLINE | ID: mdl-38842157

RESUMEN

disease, characterized by motor and vocal tics with no changes in the ocular structures in the ophthalmological evaluations. The visual field evaluations suggest a reduction in central visual field sensitivity. The studies on visual function in this population is scarce. In this case report we present a patient with GTS who has significant alterations in the measure of contrast sensitivity for second order vision without any vision complaints. This reduction occurred in the measure of contrast sensitivity with a white noise carrier for practically all tested space frequencies. The mean contrast sensitivity for first and second-order stimuli with a pink-noise carrier was normal. The second order contrast sensitivity with a white noise carrier is dependent on local and lateral inhibition since it includes many local luminance components. The existence of this sensitivity suggests that specific visual processing mechanisms are affected. Keywords: Tourette Syndrome, Contrast Sensitivity, Contrast Psychophysical Channels, Second-Order Perception.


Asunto(s)
Sensibilidad de Contraste , Síndrome de Tourette , Humanos , Masculino , Diagnóstico Diferencial , Adulto
9.
Sci Rep ; 14(1): 18711, 2024 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-39134609

RESUMEN

Humans exhibit consistent color preferences that are often described as a curvilinear pattern across hues. The recent literature posits that color preference is linked to the preference for objects or other entities associated with those colors. However, many studies examine this preference using isoluminant colors, which don't reflect the natural viewing experience typically influenced by different light intensities. The inclusion of random luminance levels (luminance noise) in chromatic stimuli may provide an initial step towards assessing color preference as it is presented in the real world. Employing mosaic stimuli, this study aimed to evaluate the influence of luminance noise on human color preference. Thirty normal trichromats engaged in a two-alternative forced-choice paradigm, indicating their color preferences between presented pairs. The chromatic stimuli included saturated versions of 8 standard hues, presented in mosaics with varying diameters under different luminance noise conditions. Results indicated that the inclusion of luminance noise increased color preference across all hues, specifically under the high luminance noise range, while the curvilinear pattern remained unchanged. Finally, women exhibit a greater sensitivity to the presence of luminance noise than men, potentially due to differences between men and women in aesthetic evaluation strategies.


Asunto(s)
Percepción de Color , Estimulación Luminosa , Humanos , Femenino , Masculino , Percepción de Color/fisiología , Adulto , Adulto Joven , Conducta de Elección/fisiología , Luz , Color
10.
Front Neurol ; 15: 1363167, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38660098

RESUMEN

Introduction: Traumatic brain injury (TBI) is an important public health concern and that may lead to severe neural sequels, such as color vision deficits. Methods: We evaluated the color vision of 10 TBI patients with normal cognitive function using a color discrimination test in a fixed saturation level. We also analyzed computerized tomography scans to identify the local of the brain damages. Results: Four TBI patients that had lesions in brain areas of the ventral visual streams, five TBI patients had lesions inferred in brain areas of the dorsal visual stream, and one TBI patient had lesion in the occipital area. All the patients had cognitive and color vision screened and they had characterized the chromatic discrimination at high and low saturation. All participants had no significant cognitive impairment in the moment of the color vision test. Additionally, they had perfect performance for discrimination of chromatic stimulus at high saturation and similar to controls (n = 37 age-matched participants). Three of four TBI patients with lesions in the ventral brain and one patient with lesion in the occipital area had impairment of the chromatic discrimination at low saturation. All TBI patients with lesions in the dorsal brain had performance similar or slightly worse than the controls. Conclusion: Chromatic discrimination at low saturation was associated to visual damage in the ventral region of the brain and is a potential tool for functional evaluation of brain damage in TBI patients.

11.
NeuroRehabilitation ; 54(2): 227-235, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38306062

RESUMEN

BACKGROUND: Premature newborns have a higher risk of abnormal visual development and visual impairment. OBJECTIVE: To develop a computational methodology to help assess functional vision in premature infants by tracking iris distances. METHODS: This experimental study was carried out with children up to two years old. A pattern of image capture with the visual stimulus was proposed to evaluate visual functions of vertical and horizontal visual tracking, visual field, vestibulo-ocular reflex, and fixation. The participants' visual responses were filmed to compose a dataset and develop a detection algorithm using the OpenCV library allied with FaceMesh for the detection and selection of the face, detection of specific facial points and tracking of the iris positions is done. A feasibility study was also conducted from the videos processed by the software. RESULTS: Forty-one children of different ages and diagnoses participated in the experimental study, forming a robust dataset. The software resulted in the tracking of iris positions during visual function evaluation stimuli. Furthermore, in the feasibility study, 8 children participated, divided into Pre-term and Term groups. There was no statistical difference in any visual variable analyzed in the comparison between groups. CONCLUSION: The computational methodology developed was able to track the distances traveled by the iris, and thus can be used to help assess visual function in children.


Asunto(s)
Recien Nacido Prematuro , Visión Ocular , Lactante , Niño , Recién Nacido , Humanos , Recien Nacido Prematuro/fisiología , Programas Informáticos , Algoritmos , Estudios de Factibilidad
12.
Front Integr Neurosci ; 17: 1129315, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37035455

RESUMEN

Purpose: Aging causes substantial changes in the intraocular lens, which leads to a reduction in chromatic perception. We aimed to measure the ocular light dispersion component in relation to the reduction in color vision by aging. Methods: Intraocular straylight was quantified psychophysically by C-Quant for light dispersion [Log(s)], reliability of the results (ESD), and psychometric sampling quality (Q). The Cambridge Color Test Trivector protocol measured the chromaticity thresholds for protan, deutan, and tritan color confusion axis in CIE 1976 u' v' units. We tested 224 subjects aged 24-68 years (106 men) with normal best-corrected visual acuity and without clinical evidence of cataracts. Results: A significant positive correlation was found between ocular dispersion of light and chromaticity thresholds for protan (r = 0.42; p < 0.001), deutan (r = 0.49; p < 0.001) and tritan (r = 0.51; p < 0.0001) color confusion axes with a moderate effect size (η2 = 0.39). However, a weak contribution of the logarithm of the straylight in predicting the chromaticity threshold for protan (b = 0.15; p = 0.025), deutan (b = 0.27; p = 0.001) and tritan (b = 0.21; p = 0.001) color confusion axes was verified in the regression coefficients. The other two measurement quality parameters estimated in the C-Quant were not correlated with chromaticity thresholds, suggesting that there are no problems with the quality of the measurement performed. Conclusion: An increase in ocular light dispersion that occurs physiologically with aging negatively impacts the chromaticity threshold in a similar manner across all three color confusion axes. The weak regression effects suggest that neural rather than optical processes were more related to the reduction in chromaticity in aging.

13.
F1000Res ; 12: 919, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38264263

RESUMEN

Background: The perception of risk regarding coronavirus disease 2019 (COVID-19) has been widely researched due to its association with the adoption of preventive measures. In addition, since the onset of vaccination, it has been reported that the population perceives a lower risk of getting infected. However, few studies have analyzed the factors associated with risk perception in low- and middle-income countries. The aim of this study was to determine the association between the risk perception of contracting COVID-19 and sociodemographic characteristics in Peruvian population. Methods: An analytical and cross-sectional study was conducted in four cities in Peru from October to December, 2021. The sample consisted of 821 individuals aged 18 years and older. A virtual questionnaire was used to collect sociodemographic data and assess the risk perception of contracting coronavirus based on the Health Belief Model. The process of back-translation, expert judgment, and reliability analysis using split-half correlation was conducted. Student's t-tests, analysis of variance with post hoc Tukey's test, and Spearman's correlation were employed. Results: Of the participants, 53.71% were women and 73.3% had a higher education level, 45.55% are self-employed, and 40.44% did not have a family member infected with COVID-19. The risk perception of COVID-19 infection was associated with participants' family antecedent of COVID-19 (p < 0.05). Regarding the factors analyzed, perceived susceptibility to COVID-19 was associated with age (p=0.002), occupation (p<0.05), and a history of COVID-19 (p<0.05), while the perceived benefits of adopting preventive measures against this disease were associated with educational level (p < 0.001). Conclusions: The risk perception of contracting COVID-19 was higher among whose had multiple infected relatives.. Furthermore, the perception of susceptibility and the perceived benefits of using preventive measures were associated with sociodemographic characteristics.


Asunto(s)
COVID-19 , Humanos , Femenino , Masculino , Estudios Transversales , Perú , Reproducibilidad de los Resultados , Percepción
14.
Front Med (Lausanne) ; 10: 1275308, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38162881

RESUMEN

Purpose: To compare the accuracy of machine learning (ML) algorithms to classify the sex of the participant from retinal thickness datasets in different retinal layers. Methods: This cross-sectional study involved 26 male and 38 female subjects. Data were acquired using HRA + OCT Spectralis, and the thickness and volume of 10 retinal layers were quantified. A total of 10 features were extracted from each retinal layer. The accuracy of various algorithms, including k-nearest-neighbor, support vector classifier, logistic regression, linear discriminant analysis, random forest, decision tree, and Gaussian Naïve Bayes, was quantified. A two-way ANOVA was conducted to assess the ML accuracy, considering both the classifier type and the retinal layer as factors. Results: A comparison of the accuracies achieved by various algorithms in classifying participant sex revealed superior results in datasets related to total retinal thickness and the retinal nerve fiber layer. In these instances, no significant differences in algorithm performance were observed (p > 0.05). Conversely, in other layers, a decrease in classification accuracy was noted as the layer moved outward in the retina. Here, the random forest (RF) algorithm demonstrated superior performance compared to the others (p < 0.05). Conclusion: The current research highlights the distinctive potential of various retinal layers in sex classification. Different layers and ML algorithms yield distinct accuracies. The RF algorithm's consistent superiority suggests its effectiveness in identifying sex-related features from a range of retinal layers.

15.
J Sep Sci ; 35(18): 2438-44, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22907894

RESUMEN

The combination of solid-phase microextraction (SPME) with comprehensive two-dimensional gas chromatography is evaluated here for fatty acid (FA) profiling of the glycerophospholipid fraction from human buccal mucosal cells. A base-catalyzed derivatization reaction selective for polar lipids such as glycerophospholipid was adopted. SPME is compared to a miniaturized liquid-liquid extraction procedure for the isolation of FA methyl esters produced in the derivatization step. The limits of detection and limits of quantitation were calculated for each sample preparation method. Because of its lower values of limits of detection and quantitation, SPME was adopted. The extracted analytes were separated, detected, and quantified by comprehensive two-dimensional gas chromatography with flame ionization detection (FID). The combination of SPME and comprehensive two-dimensional gas chromatography with FID, using a selective derivatization reaction in the preliminary steps, proved to be a simple and fast procedure for FA profiling, and was successfully applied to the analysis of adult human buccal mucosal cells.


Asunto(s)
Pared Celular/química , Ácidos Grasos/análisis , Glicerofosfolípidos/química , Mucosa Bucal/citología , Microextracción en Fase Sólida , Cromatografía de Gases , Humanos
16.
Sci Rep ; 12(1): 5603, 2022 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-35379850

RESUMEN

Color vision tests use estimative of threshold color discrimination or number of correct responses to evaluate performance in chromatic discrimination tasks. Both approaches have advantages and disadvantages. In the present investigation, we compared the number of errors during color discrimination task in normal trichromats and participants with color vision deficiency (CVD) using pseudoisochromatic stimuli at fixed saturation levels. We recruited 28 normal trichromats and eight participants with CVD. Cambridge Color Test was used to categorize their color vision phenotype, and those with a phenotype suggestive of color vision deficiency had their L- and M-opsin genes genotyped. Pseudoisochromatic stimuli were shown with target chromaticity in 20 vectors radiating from the background chromaticity and saturation of 0.06, 0.04, 0.03, 0.02, 0.01, and 0.005 u'v' units. Each stimulus condition appeared in four trials. The number of errors for each stimulus condition was considered an indicator of the participant's performance. At high chromatic saturation, there were fewer errors from both phenotypes. The errors of the normal trichromats had no systematic variation for high saturated stimuli, but below 0.02 u'v' units, there was a discrete prevalence of tritan errors. For participants with CVD, the errors happened mainly in red-green chromatic vectors. A three-way ANOVA showed that all factors (color vision phenotype, stimulus saturation, and chromatic vector) had statistically significant effects on the number of errors and that stimulus saturation was the most important main effect. ROC analysis indicated that the performance of the fixed saturation levels to identify CVD was better between 0.02 and 0.06 u'v' units reaching 100%, while saturation of 0.01 and 0.005 u'v' units decreased the accuracy of the screening of the test. We concluded that the color discrimination task using high saturated stimuli separated normal trichromats and participants with red-green color vision deficiencies with high performance, which can be considered a promising method for new color vision tests based in frequency of errors.


Asunto(s)
Defectos de la Visión Cromática , Visión de Colores , Percepción de Color/fisiología , Defectos de la Visión Cromática/diagnóstico , Defectos de la Visión Cromática/genética , Humanos , Fenómenos Físicos , Pruebas de Visión
17.
Pain Rep ; 6(4): e980, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34938935

RESUMEN

INTRODUCTION: People with chronic shoulder pain commonly report pain during arm movements in daily-life activities. Pain related to movement is commonly viewed as an accurate representation of tissue damage. Thus, when a person reports pain across a variety of movements, this is often understood as indicative of greater damage. OBJECTIVES: We aimed to investigate if movement-related pain that occurs across a wider variety of movements was associated with the number or severity of rotator cuff tendons reported as abnormal on a magnetic resonance imaging (MRI). To answer this question, this study was designed in 3 phases. METHODS: We recruited 130 individuals with chronic shoulder pain diagnosed with subacromial pain syndrome. First, a list of daily functional activities commonly reported as painful by people with chronic shoulder pain was generated from 3 well-established outcome measures with 30 individuals and a measurement tool was developed with data from further 100 individuals, which demonstrated to have acceptable content validity, construct validity, internal consistency, interrater reliability, and structural validity. Multiple linear regression was then used to evaluate the hypotheses of the study. A direct acyclic graph was used to select variables for linear regression modelling. RESULTS: There was no association between movement-related pain occurrence across movements and the MRI findings. CONCLUSION: Our study provides evidence that neither the number of rotator cuff tendons reported as abnormal nor the severity of each tendon imaging finding were associated with pain occurrence across movements and activities commonly perceived as painful by people with chronic shoulder pain.

18.
Invest Ophthalmol Vis Sci ; 62(4): 29, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33891680

RESUMEN

Purpose: The purpose of this study was to characterize changes in the full-field flash electroretinogram (ERG) in association with psychophysical dark-adapted visual thresholds in patients with genetically characterized Duchenne muscular dystrophy (DMD) either lacking Dp427 (Up 30) or at least Dp260 in addition to Dp427 (Down 30). Methods: Twenty-one patients with DMD and 27 age-similar controls participated in this study. Dark-adapted (0.01, 3.0, and 10 cd.s/m² flashes) and light-adapted (3.0 cd.s/m² flash) ERGs were recorded following International Society for Clinical Electrophysiology of Vision (ISCEV) standard protocols. Visual detection thresholds to 625-nm (cone function) and 527-nm (rod function) light-emitting diode (LED) flashes (2 degree diameter) were measured during a dark adaptation period after a 1-minute exposure to a bleaching light (3000 cd/m²). Initially, 8 minutes of interleaved 625-nm and 527-nm thresholds were measured. After an additional 5 minutes of dark-adaptation, a second set of threshold measurements to 527-nm stimuli was performed during the subsequent 6 minutes. Results: Dark-adapted b-wave amplitude was significantly reduced to all strengths of flash and a-wave in response to the strong flash stimulus was delayed (15.6 vs. 14.7 ms, P < 0.05) in patients with Down 30 compared with controls. Dark-adapted cone thresholds did not differ among the groups (-2.0, -1.8, and -1.7 log cd/m² for Down 30, Up 30, and controls, respectively, P = 0.21). In contrast, dark-adapted rod thresholds were elevated (F(2,36) = 8.537, P = 0.001) in patients with Down 30 (mean = -3.2 ± 1.1 log cd/m²) relative to controls (mean = -4.2 ± 0.3 log cd/m²). Dark-adapted b-wave amplitudes were correlated with dark-adapted rod sensitivity in patients with DMD (Spearman Rho = 0.943, P = 0.005). The changes were much smaller or absent in patients with intact Dp260. Conclusions: Dp260 is particularly required for normal rod-system function in dark adaptation.


Asunto(s)
Adaptación a la Oscuridad/fisiología , Electrorretinografía/métodos , Distrofia Muscular de Duchenne/fisiopatología , Células Fotorreceptoras Retinianas Conos/metabolismo , Umbral Sensorial/fisiología , Percepción Visual/fisiología , Adolescente , Niño , Femenino , Humanos , Masculino , Distrofia Muscular de Duchenne/patología , Estimulación Luminosa , Células Fotorreceptoras Retinianas Conos/patología , Adulto Joven
19.
Rev Saude Publica ; 54: 47, 2020.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-32491096

RESUMEN

OBJECTIVE To use the advantages of a ratio scale with verbal anchors in order to measure the risk perception in the novel coronavirus infection, which causes covid-19, in a health belief model-based questionnaire, as well as its validity and reproducibility. METHOD We used the health belief model, which explores four dimensions: perceived susceptibility (five questions), perceived severity (five questions), perceived benefits (five questions), and perceived barriers (five questions). Additionally, we included a fifth dimension, called pro-health motivation (four questions). The questions composed an electronic questionnaire disseminated by social networks for an one-week period. Answers were quantitative values of subjective representations, obtained by a psychophysically constructed scale with verbal anchors ratio (CentiMax ® ). Mean time for total filling was 12 minutes (standard deviation = 1.6). RESULTS We obtained 277 complete responses to the form. One was excluded because it belonged to a participant under 18 years old. Reproducibility measures were significant for 22 of the 24 questions in our questionnaire (Cronbach's α = 0.883). Convergent validity was attested by Spearman-Brown's split half reliability coefficient (r = 0.882). Significant differences among groups were more intense in perceived susceptibility and severity dimensions, and less in perceived benefits and barriers. CONCLUSION Our health belief model-based questionnaire using quantitative measures enabled the confirmation of popular beliefs about covid-19 infection risks. The advantage in our approach lays in the possibility of quickly, directly and quantitatively identifying individual belief profiles for each dimension in the questionnaire, serving as a great ally for communication processes and public health education.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/psicología , Infecciones por Coronavirus/transmisión , Cultura , Neumonía Viral/psicología , Neumonía Viral/transmisión , Medición de Riesgo/métodos , Encuestas y Cuestionarios/normas , Adolescente , Adulto , Anciano , Brasil , COVID-19 , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Psicológicos , Pandemias , Valores de Referencia , Reproducibilidad de los Resultados , Factores de Riesgo , SARS-CoV-2 , Factores Socioeconómicos , Adulto Joven
20.
Vision (Basel) ; 4(3)2020 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-32947801

RESUMEN

The authors wish to make the following erratum to this paper [...].

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