Caracterización óptica de lentes intraoculares = Optical characterization of intraocular lenses

The optical characterization of an intraocular lens (IOL) provides objective and quantitative information that is essential to fully understand its performance as an implant that replaces the crystalline lens in the human visual system. Additionally, it can be used to predict the performance of the new IOL designs. This thesis analyses the main sources of uncertainty in the calculation of the IOL power and the compensation of the residual refractive errors by using some unconventional degrees of freedom. The thesis focuses on the in vitro characterization of a variety of commercially available IOLs (monofocal, multifocal, spherical, aspherical, apodized, full-­-aperture, and of different materials, powers and additions) in optical bench. To this end, we have designed and implemented the necessary methods of measurement and an experimental setup that, according to the international standard regulation, reproduces the conditions of such implants in the human eye. We have developed a method to measure the energy efficiency of IOLs. This method has allowed us to explain the clinical results obtained in the evaluation of the stereoscopic acuity when using two tests based on different principles. The optical imaging quality of IOLs has been quantified through the experimental measurement of the modulation transfer function and the fringe visibility (contrast). We have developed and implemented a method to characterize some artifact, named halo, that can be perceived by those patients implanted with multifocal IOLs. Finally, all the experimental results have been used as a basis for the comparison of the IOL performances.La caracterización óptica de las lentes intraoculares (IOLs del inglés Intraocular Lenses) proporciona una información objetiva y cuantitativa que es necesaria para comprender su funcionamiento como implante que sustituye al cristalino en el sistema visual humano. Además, permite predecir el rendimiento de los nuevos diseños. Dicha caracterización se debe llevar a cabo mediante pruebas in vivo en pacientes ya implantados así como con pruebas in vitro en banco óptico o mediante simulación teórica. Esta tesis analiza las fuentes de error en el cálculo de la potencia de las lentes intraoculares y la compensación de los errores refractivos residuales mediante el uso de grados de libertad no convencionales. Se centra, fundamentalmente, en la caracterización in vitro de una variedad de lentes comercialmente disponibles (monofocales, multifocales, esféricas, asféricas, apodizadas, no-­-apodizadas, y distintos materiales, potencias y adiciones) en un banco óptico. Para ello se ha diseñado y puesto a punto los métodos de medida, un montaje experimental que reproduzca las condiciones en las que las lentes se implantan en el ojo y de acuerdo con la normativa internacional. Se ha medido la calidad óptica a través de la Función de Transferencia de Modulación o la visibilidad de franjas (contraste). Se ha desarrollado e implementado un método para la cuantificación experimental de la eficiencia energética de los distintos modelos de IOLs. Este método ha servido para explicar algunos resultados clínicos obtenidos al evaluar la visión estereoscópica con dos tests con diferente principio de funcionamiento. Se ha desarrollado e implementado un método para caracterizar el halo que perciben algunos pacientes implantados con IOLs multifocale

Energy balance in apodized diffractive multifocal intraocular lenses

Postprint (published version

Halos and multifocal intraocular lenses: origin and interpretation

Preprin

Energy Distribution between Distance and Near Images in Apodized Diffractive Multifocal Intraocular Lenses

Postprint (published version

Patient-Perceived and Laboratory-Measured Halos Associated with Diffractive Bifocal and Trifocal Intraocular Lenses

Purpose: To examine and assess the halos generated in distance vision by multifocal intraocular lenses (IOLs) using both in vitro objective and in vivo subjective methods. Setting: The objective method was carried out in the optics laboratory of the Applied Optics and Image Processing Group (Universitat Politècnica de Catalunya -Barcelona). The psychophysical and subjective methods were carried out in the Instituto de Oftalmología Avanzada Madrid Innova Ocular. Design: Optical bench results and prospective evaluation of consecutive cases. Methods: The IOLs examined were TECNIS®one-piece bifocals with addition powers of +4.00 D, +3.25 D, and +2.75 D and the trifocals AT-LISA-tri® and FineVision®. In the objective assessment, we examined halos around the far focus images of a pinhole formed by each IOL in an optical bench. For the in vivo study, we recruited 100 patients who had been bilaterally implanted one month earlier with the IOLs under study. Participants were subjected to psychophysical halometry (Halo v1.0) on the eye with better, distance-corrected, visual acuity and were required to subjectively grade halos by responding to the question “How much do halos bother you?” Results: The objective method revealed that the halo size increased with addition power and that the two trifocals gave rise to a double-halo pattern. Scores in the halometry also indicated a direct relationship between the halo size and addition power. The subjective results indicated fewer complaints about halos associated with the trifocal than bifocal IOLs. Conclusions: The addition power of the tested IOLs affected both laboratory-measured and patient-perceived halos. Trifocal lenses generated fewer complaints about halos. Precise: Multifocal intraocular lenses (MIOLs) give rise to halos observed by patients under conditions of dim lighting. This study compares laboratory characterized halos generated by five MIOLs with patient-perceived halos.Postprint (author's final draft

The tumor suppressor ING1 contributes to epigenetic control of cellular senescence

Cellular senescence is an effective tumor-suppressive mechanism that causes a stable proliferative arrest in cells with potentially oncogenic alterations. Here, we have investigated the role of the p33ING1 tumor suppressor in the regulation of cellular senescence in human primary fibroblasts. We show that p33ING1 triggers a senescent phenotype in a p53-dependent fashion. Also, endogenous p33ING1 protein accumulates in chromatin in oncogene- senescent fibroblasts and its silencing by RNA interference impairs senescence triggered by oncogenes. Notably, the ability to induce senescence is lost in a mutant version of p33ING1 present in human tumors. Using specific point mutants, we further show that recognition of the chromatin mark H3K4me3 is essential for induction of senescence by p33ING1. Finally, we demonstrate that ING1-induced senescence is associated to a specific genetic signature with a strong representation of chemokine and cytokine signaling factors, which significantly overlaps with that of oncogene-induced senescence. In summary, our results identify ING1 as a critical epigenetic regulator of cellular senescence in human fibroblasts and highlight its role in control of gene expression in the context of this tumor-protective response. Key words: cellular senescence; chromatin; ING1; p53; histone marks.This work is supported by grants from the Spanish Ministry of Science and Innovation to IP (BFU2006-10882, SAF2009-09031) and FJB (CTQ2008-03115 ⁄ BQU)

Diabetic individuals with COVID-19 exhibit reduced efficacy of gliptins in inhibiting dipeptidyl peptidase 4 (DPP4). A suggested explanation for increased COVID-19 susceptibility in patients with type 2 diabetes mellitus (T2DM)

Aims: Dipeptidyl peptidase 4 (DPP4) has been proposed as a coreceptor for SARS-CoV-2 cellular entry. Considering that type 2 diabetes mellitus (T2DM) has been identified as the most important risk factor for SARS-CoV-2, and that gliptins (DPP4 inhibitors) are a prescribed diabetic treatment, this study aims to unravel the impact of DPP4 in the intersection of T2DM/COVID-19. Materials and methods: We analyzed 189 serum human samples, divided into six clinical groups (controls, T2DM, T2DM + gliptins, COVID-19, COVID-19 + T2DM, and COVID-19 + T2DM + gliptins), measuring DPP4 protein concentration and activity by Western blot, ELISA, and commercial activity kits. The obtained results were verified in Huh-7 cellular models. Key findings: Both DPP4 concentration and activity were decreased in COVID-19 patients, and as in T2DM patients, compared to controls. Despite these lower levels, the ratio of DPP4 activity/concentration in COVID-19 sera was the highest (0.782 ± 0.289 ?U/ng vs. 0.547 ± 0.050 ?U/ng in controls, p < 0.0001), suggesting a compensating mechanism in these patients. Supernatants of Huh-7 cells incubated with COVID-19 serum showed a consistent and significantly lower DPP4 concentration and activity. Furthermore, COVID-19 + T2DM + gliptins patients showed a higher serum DPP4 concentration and activity than T2DM + gliptin subjects (p < 0.05), indicating that sera from COVID-19 convalescents interfere with gliptins. Significance: Either SARS-CoV-2 or some metabolites present in the sera of COVID-19-convalescent patients interact with soluble DPP4 or even gliptins themselves since the inhibitory effect of gliptins on DPP4 activity is being prevented. The interactions between DPP4, gliptins, and SARS-CoV-2 should be further elucidated to reveal the mechanism of action for these interesting observations.Instituto de Salud Carlos IIIComunidad de MadridUniversidad de AlcaláFundación Tatiana Pérez de Guzmán el Buen

Multidisciplinary Ophthalmic Imaging Visible Versus Near-Infrared Optical Performance of Diffractive Multifocal Intraocular Lenses

PURPOSE. The purpose of this study was to compare the optical performance of diffractive multifocal intraocular lenses (DMIOLs) with visible (VIS) illumination with that of near infrared (NIR) illumination, the latter being used to test pseudophakic eyes in clinical aberrometers and double-pass systems. METHODS. Two DMIOLs of different design (Tecnis þ2.75 D ZKB00 and AcrySof þ2.5 D SV25T0) were tested in vitro in a model eye under both VIS (k ¼ 530 nm) and NIR (k ¼ 780 nm) illumination, and variations in the add power of the lenses were determined. Moreover, for the two wavelengths, the energy efficiency and modulation transfer function at the DMIOLs&apos; far and near foci were measured with pupils of 3.0 and 4.5 mm. Two counterpart monofocal IOLs (Tecnis ZA9003 and AcrySof SN60WF) were included as references in the comparison. RESULTS. With VIS light, the two DMIOLs produced relatively well-contrasted images at their near and far foci. Under NIR illumination, the add power increased, whereas the energy efficiency of the near focus decreased and that of far focus increased. Hence, the DMIOLs tended to behave like monofocal lenses because they generated good quality well-contrasted images only at their far foci. CONCLUSIONS. In addition to changes in add power, the optical performances of the DMIOLs measured under either VIS or NIR illumination are considerably different. Whereas they show two distinct (near and far) foci under VIS light, their optical performances under NIR illumination are clearly biased in favor of their far focus. These results may help prevent a misleading use of NIR-based clinical instruments for the assessment of eyes implanted with DMIOLs. Keywords: aberrometers, cataract surgery, diffractive multifocal intraocular lens, intraocular lens, pseudophakic eye, visual function testing R emoval of the crystalline lens followed by implantation of a multifocal intraocular lens (MIOL) is presently a surgical procedure primarily aimed at providing pseudoaccommodation to patients after cataract surgery. Diffractive MIOLs (DMIOLs) have proven to provide reliable and better clinical outcomes than their refractive MIOL counterparts or accommodating IOLs, 1 so there is a growing interest in assessing their optical performance in vivo. To objectively determine the imaging quality of DMIOLs in patients, several authors have recently used both wavefront aberrometers 2,3 and double-pass-based systems. Because the wavelengths of NIR testing are quite different from the wavelength corresponding to the maximum value of the photopic sensitivity of the eye under VIS spectrum (approximately 550 nm), for which DMIOLs are designed, there is a mismatch between the NIR and VIS wavelengths, which gives rise to the following issues: -A change in add power of the DMIOL between VIS and NIR (the larger the NIR wavelength, the larger the measured add power), 12 which in turn, has an effect on halo formation and size. 14,15 -A change in distribution of energy between the foci of the DMIOL. METHODS DMIOL Characteristics The Tecnis ZKB00 DMIOL, with þ2.75 diopter (D) add power, has an aspheric anterior surface. The diffractive profile covers the full aperture of the lens and consists of 15 diffractive rings with step boundaries of the same height, intended for approximately equal light distribution between the far and near foci, independent of pupil size. The wavefront-designed aspheric optics of this DMIOL produce a maximum spherical aberration (SA) of À0.27 lm for a 6.0-mm pupil. On the other hand, the AcrySof ReSTOR SV25T0 DMIOL with þ2.5 D add power has an anterior apodized diffractive surface (3.4-mm diameter) within which there is a central refractive zone (1.0 mm diameter approximately). The outer region of the lens to the 6-mm edge is purely refractive, and thus, the central and outer refractive parts of the lens are intended for distance vision. In addition, the diffractive area presents seven concentric rings with step boundaries of decreasing height, which allows for an asymmetrical and pupil-dependent light distribution between the far and near foci that benefits the far focus for large pupils. Additionally, the reference monofocal Tecnis ZA9003 (AMO Groningen) and AcrySof SN60WF (Alcon Laboratories) IOLs were included in our study. We emphasize that each monofocal IOL shares the same aspherical design and the same material, with its diffractive counterpart. Thus, the lenses of each pair (DMIOL and monofocal counterpart) have similar characteristics regarding the compensation for high order aberration (mainly SA) and the spectral variation of the refractive index. All studied lenses had a base optical power of 20 D, which in the case of the DMIOLs corresponded to distance focus. Experimental Setup for Optical Imaging Quality Assessment Assessment of the optical imaging quality of the IOLs was made using an optical test bench with a model eye (artificial cornea plus wet cell) that has been described in detail elsewhere. 26,27 Instead, we used a double convex lens that provided a level of SA at the IOL plane of þ0.27 lm for a 6.0-mm pupil, 28 similar to the one induced by the human cornea on average. Energy Assessment and MTF Measurements by Image Analysis The method of characterizing the energy distribution at the focal planes of a DMIOL has been reported in detail elsewhere Briefly, the image in a given focal plane consisted of the core sharp image of the pinhole object surrounded by a blurred halo-shaped background. This background is principally formed from an out-of-focus image produced by the other focus of the MIOL but may have additional contributions from a variety of factors such as the energy expended in higher diffraction orders, 13 scattering produced by the diffractive steps of the lens

Bases Literarias del Imaginario Europeo II: Trasvases Culturales

El proyecto continúa la tarea iniciada en el proyecto anterior: estudiar de forma comparativa los temas comunes del imaginario literario europeo. El proyecto pone en contacto a alumnos de itinerarios diferentes ofrecidos por la Facultad de Filología. La propuesta que hacemos en este proyecto se centra en la figura del extraño y en las derivaciones que de dicho concepto se pueden extraer, como pueden ser los conceptos del otro, del forastero, del extranjero, del marginado, del desconocido, del sospechoso, del aberrante, etc. Dada la realidad social y política por la que atraviesa Europa, un acercamiento a la figura del extraño en el imaginario literario fomenta la reflexión sobre el proceso histórico-estético del continente en torno a ideas (p. ej., pertenencia y exclusión) que han regido las energías sociales en momentos históricos clave para Europa. A través del análisis del extraño en el canon europeo, los estudiantes amplían horizontes más allá de las asignaturas de su especialidad, y estudian el fenómeno literario desde una perspectiva panorámica que les permite dilucidar puntos en común o divergencias entre los textos estudiados

Novel coronavirus (SARS-CoV-2) infection in a patient with multivisceral transplant

Coronavirus disease 2019 (COVID-19) pandemic has become one of the most challenging episodes in the history of modern public health, with particular emphasis in high-risk population. However,the evidence regarding their response to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the agent responsible for COVID-19 is scant.2 Herein, we present the clinical and therapeuticcourse of a SARS-CoV-2 infection in a patient with multivisceral transplant and a recent tuberculosis infection.Fil: Papa Gobbi, Rodrigo. La Paz University Hospital. Health Research Institute; España. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bueno, Alba. La Paz University Hospital. Health Research Institute; EspañaFil: Serradilla, Javier. La Paz University Hospital. Health Research Institute; EspañaFil: Talayero, Paloma. 12 de Octubre University Hospital; EspañaFil: Stringa, Pablo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Estudios Inmunológicos y Fisiopatológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios Inmunológicos y Fisiopatológicos; ArgentinaFil: Pascual Miguel, Bárbara. La Paz University Hospital. Health Research Institute; EspañaFil: Alcolea Sánchez, Alida. La Paz University Hospital. Health Research Institute; EspañaFil: González Sacristan, Rocío. La Paz University Hospital. Health Research Institute; EspañaFil: Andrés, Ane M.. La Paz University Hospital. Health Research Institute; EspañaFil: López Santamaría, Manuel. La Paz University Hospital. Health Research Institute; EspañaFil: Rumbo, Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Estudios Inmunológicos y Fisiopatológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios Inmunológicos y Fisiopatológicos; ArgentinaFil: Ramos Boluda, Esther. La Paz University Hospital. Health Research Institute; EspañaFil: Hernández Oliveros, Francisco. La Paz University Hospital. Health Research Institute; Españ