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1.
Biomed Opt Express ; 15(2): 608-623, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38404335

RESUMO

Adaptive optics visual simulation is a powerful tool for vision testing and evaluation. However, the existing instruments either have fixed tabletop configurations or, being wearable, only offer the correction of defocus. This paper proposes a novel head-mounted adaptive optics visual simulator that can measure and modify complex ocular aberrations in real-time. The prototype is composed of two optical modules, one for the objective assessment of aberrations and the second for wavefront modulation, all of which are integrated into a wearable headset. The device incorporates a microdisplay for stimulus generation, a liquid crystal on silicon (LCoS) spatial light modulator for wavefront manipulation, and a Hartmann-Shack wavefront sensor. Miniature optical components and optical path folding structures, together with in-house 3D printed mounts and housing, were adapted to realize the compact size. The system was calibrated by characterizing and compensating the internal aberrations of the visual relay. The performance of the prototype was analyzed by evaluating the measurement and compensation of low-order and higher-order aberrations induced through trial lenses and phase masks in an artificial eye. The defocus curves for a simulated bifocal diffractive lens were evaluated in real eyes. The results show high accuracy while measuring and compensating for the induced defocus, astigmatism, and higher-order aberrations, whereas the MTF analysis shows post-correction resolution of up to 37.5 cycles/degree (VA 1.25). Moreover, the subjective test results show the defocus curves closely matched to a commercial desktop visual simulator.

2.
Biomed Opt Express ; 14(5): 2129-2137, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37206130

RESUMO

Current intraocular lenses (IOLs) are designed to substitute the cataractous crystalline lens, optimizing focus at the fovea. However, the common biconvex design overlooks off-axis performance, leading to a reduced optical quality in the periphery of the retina in pseudophakic patients compared to the normal phakic eye. In this work, we designed an IOL to provide better peripheral optical quality, closer in that respect to the natural lens, using ray-tracing simulations in eye models. The resulting design was a concave-convex inverted meniscus IOL with aspheric surfaces. The curvature radius of the posterior surface was smaller than that of the anterior surface by a factor that depended on the IOL power. The lenses were manufactured and evaluated in a custom-built artificial eye. Images of a point source and of extended targets were directly recorded at various field angles with both standard and the new IOLs. This type of IOL produces superior image quality in the whole visual field, being a better surrogate for the crystalline lens than the commonly used thin biconvex intraocular lenses.

3.
Proc Natl Acad Sci U S A ; 119(52): e2205429119, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36538483

RESUMO

Given the dire consequences of climate change and the war in Ukraine, decarbonization of electrical power systems around the world must be accomplished, while avoiding recurring blackouts. A good understanding of performance and reliability of different power sources underpins this endeavor. As an energy transition involves different societal sectors, we must adopt a simple and efficient way of communicating the transition's key indicators. Capacity factor (CF) is a direct measure of the efficacy of a power generation system and of the costs of power produced. Since the year 2000, the explosive expansion of solar PV and wind power made their CFs more reliable. Knowing the long-time average CFs of different electricity sources allows one to calculate directly the nominal capacity required to replace the current fossil fuel mix for electricity generation or expansion to meet future demand. CFs are straightforwardly calculated, but they are rooted in real performance, not in modeling or wishful thinking. Based on the current average CFs, replacing 1 W of fossil electricity generation capacity requires installation of 4 W solar PV or 2 W of wind power. An expansion of the current energy mix requires installing 8.8 W of solar PV or 4.3 W of wind power.


Assuntos
Humanos , Reprodutibilidade dos Testes , Vento , Combustíveis Fósseis , Eletricidade , Energia Renovável
4.
Biomed Opt Express ; 13(5): 2947-2959, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35774321

RESUMO

An instrument for fast and objective measurement of the peripheral refraction in the human eye is presented. The apparatus permits the automatic estimation of both defocus and astigmatism at any retinal eccentricity by scanning a near infrared beam. The design includes a Hartmann-Shack wavefront sensor and a steering mirror, which operate in combination with a compounded eyepiece for wide field operation. The basic scanning protocol allows the estimation of refraction in a circular retinal patch of 50 deg diameter (±25 from central fixation) in 3 sec. Combined with additional fixation points, wider retinal fields can be sampled to achieve a whole field. The instrument underwent calibration and testing, and its performance for real eyes was assessed in 11 subjects of varying age and refraction. The results show high repeatability and precision. The instrument provides a new tool for the investigation of peripheral optics in the human eye.

5.
J Refract Surg ; 38(4): 229-234, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35412927

RESUMO

PURPOSE: To evaluate peripheral refraction and contrast detection sensitivity in pseudophakic patients implanted with a new type of inverted meniscus intraocular lens (IOL) (Art25; Voptica SL) that was designed to provide better peripheral optics. METHODS: One month after cataract surgery, in 87 eyes implanted with the Art25 IOL, peripheral contrast detection sensitivity was measured psychophysically at 40° visual angle, both horizontally and vertically, and compared with a control group of 51 eyes implanted with standard biconvex IOLs. Thirty-one eyes with the Art25 IOL and 28 eyes from the control group were randomly selected to also measure peripheral refraction using a scanning Hartmann-Shack wavefront sensor along 80° in the horizontal meridian. RESULTS: Most patients achieved emmetropia and good visual acuity, and no significant adverse events were observed after cataract surgery with Art25 IOLs. Peripheral contrast detection sensitivity was significantly better (P < .01) in the group with the Art25 IOL in both directions (7.78 ± 3.24 vs 5.74 ± 2.60 vertical, 10.98 ± 5.09 vs 7.47 ± 3.96 horizontal), which was in agreement with the optical quality improvement in the periphery due to a reduction of defocus (1.97 and 1.21 diopters [D] at 40° temporal and nasal sides) and astigmatism (1.17 and 0.37 D at 40° temporal and nasal sides) that was statistically significant (P < .01) from 20° of eccentricity. CONCLUSIONS: Patients implanted with a new inverted meniscus IOL present a reduced amount of peripheral defocus and astigmatism compared to patients implanted with standard biconvex IOLs. This improvement in optical quality leads to better contrast detection sensitivity measured at 40° of eccentricity. [J Refract Surg. 2022;38(4):229-234.].


Assuntos
Astigmatismo , Catarata , Lentes Intraoculares , Menisco , Facoemulsificação , Astigmatismo/cirurgia , Sensibilidades de Contraste , Humanos , Implante de Lente Intraocular , Pseudofacia/cirurgia , Refração Ocular , Acuidade Visual
6.
Rev. esp. nutr. comunitaria ; 28(Supl. 1): 255-284, 02/03/2022. ilus
Artigo em Espanhol | IBECS | ID: ibc-221487

RESUMO

En un territorio no muy extenso, el mar y la montaña se abrazan creando un clima singular y una tierra privilegiada. Su cocina es el reflejo de la tierra, de la forma de vivir de los vascos y de su historia. La cocina vasca cuenta con un vasto recetario y una fuerte cocina popular. Al repertorio de alimentos presentes en la alimentación de los vascos se incorporaron nuevos productos procedentes del continente americano que con el tiempo desplazaron algunos de los alimentos básicos y se han convertido en clásicos imprescindibles en los fogones: alubias, tomates, pimientos. Una tradición culinaria basada en la calidad delos productos y técnicas sencillas que incorporaron procedimientos elaborados y sofisticados en el siglo XIX a partir de influencias europeas. A partir de 1977, el impulso de la nueva cocina vasca a permitido una extraordinaria evolución en la que conviven las nuevas tendencias con el culto a las tradiciones y peculiaridades gastronómicas, como los txokos y sociedades gastronómicas; los pintxos; sidrerías y tabernas. (AU)


In a not very extensive territory, the sea and the mountains embrace each other creating a unique climate and a privileged land. Its cuisine reflects the land, the Basque way of life and its history. Basque cuisinehas a vast recipe collection and a strong popular cuisine. New products from the American continent were added to the repertoire of foods present in the diet of the Basques. Over time displaced some of the basic foods and have become essential classics in the kitchen: beans, tomatoes, peppers. A culinary tradition based onthe quality of the products and simple techniques that incorporated elaborate and sophisticated procedures inthe 19th century based on European influences. Starting in 1977, the impulse of the new Basque cuisine has allowed an extraordinary evolution in which new trends coexist with the cult of gastronomic traditions and peculiarities, such as txokos and gastronomic societies; the pintxos; cider houses and taverns. (AU)


Assuntos
Humanos , Refeições , Refeições/etnologia , Ambiente Marinho/etnologia , Cultura , Culinária , Espanha/etnologia , Livros de Culinária como Assunto
7.
Biomed Opt Express ; 12(6): 3282-3295, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34221660

RESUMO

The purpose of this work is to study the dynamics of the accommodative response as a function of the subject's refractive error, as a first step in determining whether an anomalous accommodative function could affect emmetropization or trigger myopia progression. A secondary goal was to establish potential relationships between the speed of accommodation and other parameters in the accommodation process. Parameters related to the speed and amplitude of accommodation, convergence, miosis, and change in high-order aberrations were measured during the accommodative process for 2.8 D demand in 18 young healthy subjects (mean age 25.0 ± 4.7 years) with a range of refractive errors between 0 and -7.5 D (spherical equivalent). Measurements were performed in real time (25 Hz) with an open-view binocular Hartmann-Shack (HS) sensor using a GPU-based processing unit. Correlation coefficients were calculated between refractive error and each computed variable. Additionally, the speed of accommodation was correlated with all the other parameters in the study. Correlation coefficients with refractive error had non-zero values for several parameters of the accommodative response but p-values were higher than 0.05 except in two cases: with pupil miosis speed (R = -0.49, p = 0.041) and with lag of accommodation (R = -0.57, p = 0.014). Additionally, correlation values with p-value < 0.05 were found between accommodation speed and convergence duration (R = 0.57, p = 0.014), convergence speed (R = 0.48, p = 0.044), and pupil miosis amplitude (R = 0.47, p = 0.049). We did not find strong evidence of a link between myopia and altered dynamics of the accommodation process. Only miosis speed was found to be correlated to refractive error with p < 0.05, being slower for myopes. On the other hand, increased lag of accommodation tends to be associated to larger refractive errors. Additionally, our data suggests that the faster the accommodation, the faster and longer the convergence and the larger the pupil miosis.

8.
J AOAC Int ; 104(1): 172-179, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33064804

RESUMO

BACKGROUND: The use of hypoallergenic infant formulas and the need for reliable tests to determine the presence of residual antigens have increased in parallel. OBJECTIVE: An LC-MS method for quantitation of casein was validated using incurred samples and a matrix-matched external standard curve. METHOD: Powdered infant formula samples were extracted in a buffer of sodium deoxycholate and ammonium bicarbonate at 60°C and filtered through 7 kDa desalting columns. Samples were digested overnight with trypsin and precipitated with acid prior to analysis of marker peptides by tandem mass spectrometry. RESULTS: Based on three marker peptides, the linear range for casein was 1.8-42 µg/g of powdered infant formula with an LOQ of 1.8 µg/g. The determination coefficients (R2) for each curve were ≥0.99 for casein peptides. Method repeatability was ≤22% RSD and intermediate precision was ≤23% RSD; recovery of casein from incurred material (2-20 µg/g) ranged from 78% to 118%. CONCLUSIONS: An LC-MS/MS method was developed and validated for confirmation of casein allergens in hypoallergenic infant formula. HIGHLIGHTS: A method was developed to accurately and reliably quantify casein allergens in extensively hydrolyzed casein infant formula by LC-MS without the need for custom peptide standards.


Assuntos
Fórmulas Infantis , Espectrometria de Massas em Tandem , Alérgenos , Caseínas , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Humanos , Lactente , Fórmulas Infantis/análise
9.
Opt Express ; 28(23): 34180-34189, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33182893

RESUMO

Spatial Light Modulators (SLMs) are widely used in several fields of optics such as adaptive optics. SLMs based on Liquid Crystal (LC) devices allow a dynamic and easy representation of two-dimensional phase maps. A drawback of these devices is their elevated cost, preventing a massive use of the technology. We present a more affordable approach based on the serial arrangement of vertical aligned LC devices, with characteristics of phase modulation similar to a widely used parallel aligned LC device. We discuss the peculiarities of the approach, the performance and some potential areas of applications.

10.
Rev. esp. drogodepend ; 44(2): 26-42, abr.-jun. 2019. tab
Artigo em Espanhol | IBECS | ID: ibc-184428

RESUMO

Las nuevas tecnologías de la información y la comunicación (TIC) han cambiado el mundo. Sabemos de sus ventajas: velocidad, accesibilidad, superación de barreras, intercomunicación en tiempo real en cualquier lugar, entre otras. Sin embargo, este avance tecnológico también tiene sus peligros: el mal uso, la posible adicción, riesgo de prácticas como el cy-berbullying, el grooming, suplantación de identidad, entre otros. Prácticas que en vez de potenciar al ser humano lo puede incluso destruir. En este trabajo se presentan los principales resultados de un estudio descriptivo sobre uso que hacen de las TICs, jóvenes residentes en la Comunidad Canaria. Para ello fueron entrevistados un total de 6134 jóvenes (entre 12 y 17 años) afincados en las 7 islas del archipiélago. Se exponen resultados (porcentajes y Chi cuadrado) sobre el uso de internet, teléfono móvil, videojuegos y apuestas en línea de la muestra estudiada. Estos resultados pretenden contribuir a describir los patrones de uso de las TIC en población juvenil, así como a establecer los límites entre el uso y el mal uso de estas tecnologías


New information and communication technologies (ICT) have changed the world. Their advantages are well known: speed, accessibility, overcoming barriers, intercommunication in real time anywhere, etc. These technological advances nevertheless also have their dangers: misuse, possible addiction, risks such as cyberbullying, grooming, identity impersonation, etc., Instead of empowering the human being, these practices can even destroy him. The present work is a descriptive study of the use of ICT (Information and communication technology) by young people living in the Canary Islands. A total of 6134 teenagers (from 12 to 17 years old) settled on the seven islands of the archipelago were interviewed. Results (percentages and Chi square) are presented on the use of the Internet, mobile phone, videogames and online bets. These results are intended to help to clarify the boundaries between the use and abuse of these technologies


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Jogos de Vídeo/estatística & dados numéricos , Acesso à Internet/estatística & dados numéricos , Redes Sociais Online , Comportamento do Adolescente , Entrevistas como Assunto , Espanha/epidemiologia
11.
J Cataract Refract Surg ; 45(1): 87-93, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30309774

RESUMO

PURPOSE: To clinically validate an adaptive optics visual simulator (VAO) that measures subjective refraction and visual acuity. SETTING: Optics Laboratory, University of Murcia, Murcia, Spain. DESIGN: Prospective case series. METHODS: Using the adaptive optics visual simulator, 2 examiners measured the subjective refraction and visual acuity in healthy eyes of volunteers; 1 examiner also used a trial frame as a gold standard. The interexaminer reproducibility and agreement with the gold standard were estimated using the following statistical parameters: limits of agreement from Bland-Altman analysis, significance between differences (P value), and intraclass correlation coefficient (ICC). RESULTS: Seventy-six eyes of 38 volunteers were measured. Interexaminer reproducibility for subjective refraction was excellent (ICC ≥0.96; P > .05), with low 95% confidence interval (CI) values for the power vectors M (spherical equivalent of the given refractive error), J0 (Jackson cross-cylinder, axes at 180 degrees and 90 degrees), and J45 (Jackson cross-cylinder, axes at 45 degrees and 135 degrees) (±0.51 diopter [D], ±0.14 D, and ±0.14 D, respectively). No significant differences in subjective refraction and visual acuity were found between the visual simulator and gold standard (P > .05), with 95% CIs for M, J0, and J45 (subjective refraction) of ±0.67 D, ±0.14 D, and ±0.16 D, respectively, and a ±0.10 logarithm of the minimum angle of resolution (visual acuity). CONCLUSION: Subjective refraction results using the adaptive optics visual simulator agreed with those of the gold standard and can be used as the baseline for visual simulation of any optical corneal profile or intraocular lens design for refractive surgery patients.


Assuntos
Aberrometria/instrumentação , Córnea/fisiologia , Refração Ocular/fisiologia , Acuidade Visual/fisiologia , Adulto , Idoso , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Óptica e Fotônica , Estudos Prospectivos , Reprodutibilidade dos Testes , Adulto Jovem
12.
Ansiedad estrés ; 23(1): 27-31, ene.-jun. 2017. tab
Artigo em Inglês | IBECS | ID: ibc-164022

RESUMO

The arrival of a new-born baby drastically changes the parents' lives. Several authors have reached the conclusion that this vital event can even lead to a post-traumatic stress disorder. This fact is especially relevant when it comes to correctly coping with this situation. The role played by the emotions involved in this process as well as the stress suffered by parents experiencing such a change are recognized by previous studies. In this paper, we carried out a comparative study between the emotions and stressful situations experienced by preterm and term babies’ progenitors. The results show how the group of parents of preterm babies is more affected by stress and negative emotions. In this sense, the spectrum widens to an almost unprecedented relevant field in psychological research that allows us to see how the parents of premature children experience this circumstance


La llegada de un nuevo hijo cambia drásticamente la vida de los padres. Algunos autores han llegado a la conclusión de que estos eventos vitales incluso pueden llegar a producir un trastorno de estrés postraumático. Este hecho es especialmente relevante para afrontar correctamente la situación. Está reconocido el papel que tienen las emociones involucradas en este proceso así como el estrés que sufren los padres que experimentan este cambio. En este trabajo desarrollamos un estudio comparativo entre las emociones y las situaciones de estrés experimentadas en padres con niños que han nacido a término frente a padres de niños que han nacido prematuros. Los resultados muestran cómo el grupo de padres de niños nacidos prematuros sufre más estrés y emociones negativas que el grupo de padres de niños que nacen a término. En este estudio se abre la puerta a un campo relevante casi inédito en la investigación psicológica que nos permite ver cómo los padres de niños prematuros viven esta circunstancia


Assuntos
Humanos , Feminino , Masculino , Adulto , Pais/psicologia , Nascimento Prematuro/psicologia , Nascimento a Termo/psicologia , Estresse Psicológico/psicologia , Sintomas Afetivos/epidemiologia , Acontecimentos que Mudam a Vida
13.
Opt Express ; 25(9): 9793-9801, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28468359

RESUMO

The chromatic behavior of diffractive optical elements, exhibiting 2π-wrapped phase profiles, implemented into liquid crystal spatial light modulators (LC-SLM) is described. A wrapped phase map is only equivalent to the original continuous profile for the design wavelength while at other wavelengths there are unwanted phase jumps and the profile does not correspond to a pure defocus. For those conditions the wrapped profile behaves as a multiple order lens (multi-focal lens). The optical power dispersion for each order is linearly proportional to the wavelength, while the energy of each order depends on the design wavelength and the material dispersion. For practical purposes, for most of the visible range only first order (main defocus) is relevant but two other orders may also be considered depending on the actual PSF of the system. As an application, we demonstrate that the longitudinal chromatic aberration of the eye can be compensated by the diffractive lens dispersion when the appropriate defocus is programmed into the SLM.

14.
Opt Express ; 24(13): 14159-71, 2016 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-27410574

RESUMO

An auto-referenced interferometric method for calibrating phase modulation of parallel-aligned liquid crystal (PAL) spatial light modulators (SLM) is described. The method is experimentally straightforward, robust, and requires solely of a collimated beam, with no need of additional optics. This method uses the SLM itself to create a tilted plane wave and a reference wave which mutually interfere. These waves are codified by means of a binary diffraction grating and a uniformly distributed gray level area (piston) into the SLM surface. Phase shift for each gray level addressed to the piston section can then be evaluated. Phase modulation on the SLM can also be retrieved with the proposed method over spatially resolved portions of the surface. Phase information obtained with this novel method is compared to other well established calibration procedures, requiring extra elements and more elaborated optical set-ups. The results show a good agreement with previous methods. The advantages of the new method include high mechanical stability, faster performance, and a significantly easier practical implementation.

15.
J Vis ; 16(8): 16, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27333457

RESUMO

Night myopia, which is a shift in refraction with light level, has been widely studied but still lacks a complete understanding. We used a new infrared open-view binocular Hartmann-Shack wave front sensor to quantify night myopia under monocular and natural binocular viewing conditions. Both eyes' accommodative response, aberrations, pupil diameter, and convergence were simultaneously measured at light levels ranging from photopic to scotopic conditions to total darkness. For monocular vision, reducing the stimulus luminance resulted in a progression of the accommodative state that tends toward the subject's dark focus or tonic accommodation and a change in convergence following the induced accommodative error. Most subjects presented a myopic shift of accommodation that was mitigated in binocular vision. The impact of spherical aberration on the focus shift was relatively small. Our results in monocular conditions support the hypothesis that night myopia has an accommodative origin as the eye progressively changes its accommodation state with decreasing luminance toward its resting state in total darkness. On the other hand, binocularity restrains night myopia, possibly by using fusional convergence as an additional accommodative cue, thus reducing the potential impact of night myopia on vision at low light levels.


Assuntos
Acomodação Ocular/fisiologia , Adaptação à Escuridão/fisiologia , Escuridão , Miopia/fisiopatologia , Visão Noturna/fisiologia , Visão Binocular/fisiologia , Adulto , Feminino , Humanos , Masculino , Testes Visuais
16.
Sci Rep ; 6: 25551, 2016 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-27151778

RESUMO

Presbyopia, the loss of the eye's accommodation capability, affects all humans aged above 45-50 years old. The two main reasons for this to happen are a hardening of the crystalline lens and a reduction of the ciliary muscle functionality with age. While there seems to be at least some partial accommodating functionality of the ciliary muscle at early presbyopic ages, it is not yet clear whether the muscle is still active at more advanced ages. Previous techniques used to visualize the accommodation mechanism of the ciliary muscle are complicated to apply in the older subjects, as they typically require fixation stability during long measurement times and/or to have an ultrasound probe directly in contact with the eye. Instead, we used our own developed method based on high-speed recording of lens wobbling to study the ciliary muscle activity in a small group of pseudophakic subjects (around 80 years old). There was a significant activity of the muscle, clearly able to contract under binocular stimulation of accommodation. This supports a purely lenticular-based theory of presbyopia and it might stimulate the search for new solutions to presbyopia by making use of the remaining contraction force still presented in the aging eye.


Assuntos
Acomodação Ocular , Contração Muscular , Músculos/fisiologia , Idoso , Idoso de 80 Anos ou mais , Humanos , Pseudofacia
17.
Biomed Opt Express ; 6(10): 4200-11, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26504666

RESUMO

We have studied the temporal dynamics of the near response (accommodation, convergence and pupil constriction) in healthy subjects when accommodation was performed under natural binocular and monocular viewing conditions. A binocular open-view multi-sensor based on an invisible infrared Hartmann-Shack sensor was used for non-invasive measurements of both eyes simultaneously in real time at 25Hz. Response times for each process under different conditions were measured. The accommodative responses for binocular vision were faster than for monocular conditions. When one eye was blocked, accommodation and convergence were triggered simultaneously and synchronized, despite the fact that no retinal disparity was available. We found that upon the onset of the near target, the unblocked eye rapidly changes its line of sight to fix it on the stimulus while the blocked eye moves in the same direction, producing the equivalent to a saccade, but then converges to the (blocked) target in synchrony with accommodation. This open-view instrument could be further used for additional experiments with other tasks and conditions.

18.
J Nutr Biochem ; 26(5): 455-65, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25662731

RESUMO

Human milk oligosaccharides (HMOs) are unique with regard to their diversity, quantity and complexity, particularly in comparison to bovine milk oligosaccharides. HMOs are associated with functional development during early life, mainly related to immunity and intestinal health. Whether HMOs elicit a positive effect on cognitive capabilities of lactating infants remains an open question. This study evaluated the role of the most abundant HMO, 2'-fucosyllactose (2'-FL), in synaptic plasticity and learning capabilities in rodents. Mice and rats were prepared for the chronic recording of field excitatory postsynaptic potentials evoked at the hippocampal CA3-CA1 synapse. Following chronic oral administration of 2'-FL, both species showed improvements in input/output curves and in long-term potentiation (LTP) evoked experimentally in alert behaving animals. This effect on LTP was related to better performance of animals in various types of learning behavioral tests. Mice were tested for spatial learning, working memory and operant conditioning using the IntelliCage system, while rats were submitted to a fixed-ratio schedule in the Skinner box. In both cases, 2'-FL-treated animals performed significantly better than controls. In addition, chronic administration of 2'-FL increased the expression of different molecules involved in the storage of newly acquired memories, such as the postsynaptic density protein 95, phosphorylated calcium/calmodulin-dependent kinase II and brain-derived neurotrophic factor in cortical and subcortical structures. Taken together, the data show that dietary 2'-FL affects cognitive domains and improves learning and memory in rodents.


Assuntos
Hipocampo/efeitos dos fármacos , Aprendizagem/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Trissacarídeos/farmacologia , Animais , Hipocampo/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Leite Humano , Ratos , Ratos Sprague-Dawley
19.
Invest Ophthalmol Vis Sci ; 56(2): 962-6, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25613944

RESUMO

PURPOSE: Quality of vision in patients who have undergone corneal refractive surgery depends upon the optimal centration of the procedures used. The center of the pupil is used as a reference point in some corneal ablation procedures. The achromatic axis would be a more sensible option from an optical point of view, but it is not as readily detectable. As an alternative, other refractive techniques, like the small aperture corneal inlay for presbyopia correction, use the corneal reflex (first Purkinje image). To assess the relative position of these two marks, we developed a new instrument to simultaneously measure both the first Purkinje image (PI) and the intersection of the achromatic axis with the pupil plane. METHODS: The apparatus records images of the pupil and the PI when illuminated with a circle of infrared light-emitting diodes. A second optical path allows determination of the achromatic axis by using a subjective method. Both the positions of the PI and the achromatic axis intersection are determined simultaneously. RESULTS: A series of data were obtained in 48 eyes. The mean location of the achromatic point relative to the PI was [x = -0.05 ± 0.15 mm; y = 0.09 ± 0.18 mm]. Considered individually, in 55% of eyes, the distance between locations is less than 0.2 mm, and in 95% of eyes, distances are less than 0.4 mm. CONCLUSIONS: On average, achromatic axis crossing of the pupil and PI locations coincides within measurement errors. Although there was some intersubject variability, differences in location were less than 0.6 mm in all measured eyes.


Assuntos
Piscadela/fisiologia , Córnea/patologia , Presbiopia/diagnóstico , Pupila/fisiologia , Acuidade Visual , Aberrometria/métodos , Adulto , Topografia da Córnea , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Presbiopia/fisiopatologia , Valores de Referência , Adulto Jovem
20.
Biomed Opt Express ; 5(10): 3355-66, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25360355

RESUMO

Corneal small aperture inlays provide extended depth of focus as a solution to presbyopia. As this procedure is becoming more popular, it is interesting to compare its performance with traditional approaches, such as monovision. Here, binocular visual acuity was measured as a function of object vergence in three subjects by using a binocular adaptive optics vision analyzer. Visual acuity was measured at two luminance levels (photopic and mesopic) under several optical conditions: 1) natural vision (4 mm pupils, best corrected distance vision), 2) pure-defocus monovision ( + 1.25 D add in the nondominant eye), 3) small aperture monovision (1.6 mm pupil in the nondominant eye), and 4) combined small aperture and defocus monovision (1.6 mm pupil and a + 0.75 D add in the nondominant eye). Visual simulations of a small aperture corneal inlay suggest that the device extends DOF as effectively as traditional monovision in photopic light, in both cases at the cost of binocular summation. However, individual factors, such as aperture centration or sensitivity to mesopic conditions should be considered to assure adequate visual outcomes.

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