Person:
Peral Cerda, María Asunción

First Name

María Asunción

Last Name

Peral Cerda

URI

https://hdl.handle.net/20.500.14352/79914

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Óptica y Optometría

Department

Optometría y Visión

Area

Optica

Identifiers

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Now showing 1 - 10 of 29

Importance of Lid Hygiene Before Ocular Surgery: Qualitative and Quantitative Analysis of Eyelid and Conjunctiva Microbiota
(Eye & Contact Lens: Science & Clinical Practice, 2016) Peral Cerda, María Asunción; Alonso Fernández, José; García García, María De La Concepción; Niño Rueda, Cristina; Calvo del Bosque, Patricia
Objective: To evaluate the efficacy of a cleansing eyelid wipe in reducing the microbiota present on the ocular surface before cataract surgery. Methods: A single-center, prospective, single-blind phase IV study was conducted at the University Complutense of Madrid. Forty-five adult patients who were scheduled for ocular surgery after treatment with commercially available eyelid wipes were consecutively enrolled. The study lasted 5 days and the patients were examined at day 0 (D0), day 3 (D3), and day 5 (D5). They received instructions to apply the eyelid wipe only to the eye subject to surgery, using the other eye as a control with no treatment. Lid and conjunctival swabs were taken on each day and microbes identified. Ocular surface microbiota was estimated by measuring the area of the agar plate occupied by the grown colonies with respect to the total available area. Results: Measurements at D3 and D5 showed a percent reduction of 58% and 63%, respectively, in the microbial load on the eyelid in the treated eyes (P=0.0011). There was also a reduction, although nonsignificant, in the microbiota of the conjunctiva of 72% and 69% on D3 and D5, respectively. Conclusions: The degree of microbiota reduction was comparable with that obtained after topical application of antibiotics in other studies. The results suggest the use of these eyelid wipes as a complementary prophylactic method before any ocular surgery.
Effect of illuminating wavelength on the contrast of meibography images
(OSA Continuum, 2018) Peral Cerda, María Asunción; Alonso Fernández, José; Gómez Pedrero, José Antonio
Evaluation of the Meibomian glands morphology is becoming a popular assessment for dry eye. This evaluation is usually done by imaging the glands on the everted lids while they are illuminated with infrared light. Nowadays techniques to determine gland condition and dropout are based on grading scales with which meibography images are subjectively evaluated. In this work, we have measured the contrast of Meibomian gland images from ten subjects and for a range of wavelengths of the monochromatic illuminating light. We have used a xenon lamp and a monochromator as a light source, and a semi-automatic image processing technique for measuring the image contrast from 600 nm to 1050 nm. Contrast values inside glands are from 0.025 to 0.015 and between glands from 0.06 to 0.04. The greater values of contrast are obtained when Meibomian glands are illuminated with a wavelength close to 600 nm.
Improving ocular surface comfort in contact lens wearers
(Contact Lens and Anterior Eye, 2021) Fernández Jiménez, Elena; Diz Arias, Elena; Peral Cerda, María Asunción
Purpose Contact lens discomfort (CLD) is a major concern that can lead to the decreased or abandoned use of contact lenses. Contact lens users with dry eye disease are more likely to present with CLD. This study was conducted to evaluate the efficacy of a bioprotective preservative free, hypotonic, 0.15% hyaluronic acid (HA)-3% Trehalose artificial tear in managing dry eye symptoms in contact lens wearers. Methods A prospective, single-arm, observational pilot study to evaluate the effectiveness of treatment with HA-Trehalose artificial tears in contact lens wearers (N = 33) aged 18–45 years with symptoms of ocular discomfort. Participants used a preservative-free, hypotonic HA-Trehalose artificial tear (1 drop/4 times per day) for 84 days. Participants were assessed using Visual Analogue Scale (VAS) for dry eye symptoms (pain, photophobia, dry eye sensation, blurry vision, foreign body sensation, itching, tingling/burning, and sticky eye feeling), Ocular Surface Disease Index (OSDI), Contact Lens Dry Eye questionnaire (CLDEQ-8), Berkley Dry Eye Flow-Chart (DEFC) on Day 0 and Day 84 and tear break-up time (TBUT), ocular surface staining with fluorescein and lissamine green, tear meniscus evaluation, and visual acuity on Day 0, 35, and 84. Results All VAS symptoms (except tingling/burning and sticky eye feeling), OSDI, CLEDQ-8, and DEFC showed statistically significant (p < 0.05) improvement from baseline (Day 0) to Day 84. Similarly, corneal (fluorescein) and conjunctival (lissamine green) quality improved during the study (p < 0.05 at Day 84 versus baseline). Tear break-up time (TBUT), conjunctival (lissamine green) staining, and tear meniscus decreased but the changes were not statistically significant. Visual acuity did not change during the study. There were no ocular or systemic adverse events. Conclusions This study showed that the instillation of a preservative-free, hypotonic, HA-Trehalose artificial tear in contact lenses wearers with dry eye syndrome significantly improved symptoms and reduced associated signs such as corneal and conjunctival staining.
Variation of Meibomian glands contrats throughout the day
(2024) Peral Cerda, María Asunción; Fernandez Jimenez Elena; Diz Arias, Elena; Gómez Pedrero, José Antonio; Peral Cerda, María Asunción; Gómez Pedrero, José Antonio; Peral A
Purpose: To evaluate Meibomian glands (MG), specialized imaging techniques are used. The most commonly used technique for the observation of MG is non-contact meibography with infrared light. This technique allows to see specific details of the MG, provides quantitative measurements, in addition to structural appearance, shortening, distortions or atrophy. [1] Recent studies have shown that the analysis of MG contrasts can represent an advance in the diagnosis of related pathologies to MG, such as Meibomian gland dysfunction and Blepharitis. [2] The present study wants to observe the contrast variation throughout the day in the spaces between two adjacent MG, interglandular contrasts (CINTER) and within the same gland, intraglandular contrasts (CIN). The main objective of this study is to observe the variation of MG contrasts throughout the day and analyze its possible correlation with alterations related to these glands. Methods: A prospective, descriptive, pilot study was carried out on 8 participants, including controls, MG pathology participants, and contact lens users. A set of tests were performed, including symptomatology tests, clinical tests to recognize the ocular surface and an assessment of the MG. Images of the MG were taken throughout the day, with the Oculus Keratograph 5MTM. Meibography images were captured from 8 am to 8 pm in two hours slots. The eyelids were everted and the images were always captured by the same clinical examiner. The meibography images have been processed with the Matlab® program to analyze the CINTER and CIN contrast. [3] Results: Preliminary results show that there is an oscillatory and fluctuating trend in glandular contrasts throughout the day, following different patterns in each subject. Conclusions: As has been previously studied, MG contrasts are postulated as a possible biomarker of MG alterations. The study of the behavior of these contrasts throughout the day and in different groups of subjects may lead to advances in the diagnosis of MG alterations or pathologies such as Meibomian gland dysfunction or Blepharitis, and could also provide further insight on the meibum production cycle and MG physiology.
Therapeutic Targets in Dry Eye Syndrome
(Drug News Perspect, 2008) Peral Cerda, María Asunción; Domínguez Godínez, Carmen Olalla; Carracedo Rodríguez, Juan Gonzalo; Pintor Just, Jesús Jerónimo; Prous Science
Dry eye is a multifactorial disease of the tears and the ocular surface that manifests with a wide variety of signs and symptoms. It is prevalent in about 33% of the population worldwide. Due to the importance of the pathology, new tests, drugs and technologies have been developed to assist the diagnosis, management and follow-up of the disease. Current available therapies try to alleviate symptoms and to reduce signs in order to restore the ocular surface. Depending on the etiology of the pathology it is possible to use lubricants, secretagogues, biological tear substitutes or antiinflammatory drugs, either independently or combined. Nowadays, the therapies under clinical trial are devoted to stimulating tear components (e.g., diquafosol, a P2Y receptor agonist), or mucin secretion (e.g., rebamipide, an amino acid analogue of quinolinone). Others include gefarnate, a water-insoluble terpene fatty acid that contributes to restoring mucins on the ocular surface, or cevimeline, an oral cholinergic agonist that reduces the symptoms associated with dry eye. Other potential compounds described in patents are in a lower phase of drug development. These compounds come from different families of therapies, and among others, can be found in the form of steroidal and nonsteroidal antiinflammatory agents, vitamins A and D, neurotransmitters and neuropeptides.
Melatonin Makes Me Feel Awake! Seven Years of Lab Experience (2000-2007)
(Anales de la Real Academia Nacional de Farmacia, 2007) Pelaez, Teresa; Mediero Muñoz, Aránzazu; Alarma-Estrany, Pilar; Loma Lozano, Patricia; Guzmán Aránguez, Ana Isabel; Crooke Álvarez, Almudena; Colligris, Basilio; Peral Cerda, María Asunción; Pintor Just, Jesús Jerónimo
The research on the effect of melatonin on intraocular pressure (IOP) is reviewed from the hystorical point of view of our laboratory. The original idea of melatonin modulating intraocular pressure has been improved by using selective compounds for MT2 and specially melatonin MT3 receptors. The selective compound 5-methoxyamino N-acetyltryptamine (5-MCA-NAT) has been an attractive compound due to its ability to reduce IOP about 40%, therefore being a good candidate to the treatment of the ocular hypertension linked to glaucoma. More compounds have been developed and tested permitting us to have a more accurate panorama of those receptors controlling the relevant process of intraocular pressure.
Therapeutic potential of topical administration of siRNAs against HIF-1α for corneal neovascularization
(Experimental Eye Research, 2022) Peral Cerda, María Asunción; Mateo Ibáñez, Jesús; Domínguez Godínez, Carmen Olalla; Carracedo Rodríguez, Juan Gonzalo; Gómez Pedrero, José Antonio; Crooke Álvarez, Almudena; Pintor Just, Jesús Jerónimo
Given the implications of the problem of neovascularization on ocular health, as well as the growth in the number of cases, the purpose of the present study has been testing the efficacy of siRNAs (small interfering RNA) designed to silence Hypoxia Inducible Factor -1α (HIF-1α) and to demonstrate that their use stops neovascularization in a model of corneal burn. Corneal wounds in the limbic zone were made in the eyes of New Zealand white rabbits. Topical applications of siRNAs were done the next day to the wound for four consecutive days and eyes were examined with a slit lamp. Evaluation of neovascularization progress was done by analyzing images by ImageJTM and to determine the neovascular area in Matlab ® was used. At the same time, a rabbit corneal cell line was used for in vitro study of hypoxia exposure and Western blot analysis of the cell's extracts were done. Under normal cell culture oxygenation, the expression of HIF-1α was lower than that observed under hypoxic conditions. After 2 h of hypoxia, there was a significant increase in the HIF-1α expression, effect that was maintained up to 6 h. The increased in HIF-1α was mimicked by a cell permeable prolyl-4-hydroxylase inhibitor. Cobalt chloride showed no capacity to increase HIF-1α in vitro. The effect of three different siRNA on HIF-1α was tested after 4 h of hypoxia. siRNA#1 was able to silence 80% of HIF-1α expression, siRNA#2 and siRNA#3 reduce the expression in 45% and 40% respectively. In addition, the three siRNA were tested in a corneal model of neovascularization. scrambledsiRNA#2 was the most effective inhibitor of blood vessel production, followed by siRNA#3 and siRNA#1. Compared to the scrambled siRNA (100% of blood vessel generation), siRNA#2 blocked the presence of blood vessels by 83 ± 2%, siRNA#3 inhibited 45 ± 7% and siRNA#1 only inhibited 18 ± 5%. The necessary time to observe the 50% of effect showed values of NV50 of 10.2 ± 2.4 days for the scrambled siRNA, 9.1 ± 1.4 for siRNA#1, 6.5 ± 1.85 for siRNA#2 and 4.8 ± 1.8 days for siRNA#3. In conclusion, the topical application of siRNA towards HIF-1α seems to be an effective and reliable method to stop neovascularization.
Corneal Re-epithelialization Stimulated by Diadenosine Polyphosphates Recruits RhoA/ROCK and ERK1/2 Pathways
(Investigative Ophthalmology & Visual Science, 2008) Mediero Muñoz, Aránzazu; Guzmán Aránguez, Ana Isabel; Crooke Álvarez, Almudena; Peral Cerda, María Asunción; Pintor Just, Jesús Jerónimo
Purpose. To investigate the role of ERK1/2 and RhoA/ROCK intracellular pathways in the modification of corneal re-epithelialization when stimulated by the diadenosine polyphosphates Ap4A and Ap3A. Methods. In wounded confluent SIRC (Statens Seruminstitut rabbit cornea) cell monolayers and in the presence or absence of Ap4A or Ap3A 100 μM, a battery of P2 receptor antagonists and inhibitors of tyrosin kinases, MAPK, and cytoskeleton pathways (AG1478 100 μM, U0126 100 μM, Y27632 100 nM, and (−)-blebbistatin 10 μM; n = 8 each) were assayed. Also, the activation of ERK1/2 and ROCK-I was examined by Western blot assay after treatment with Ap4A and Ap3A (100 μM), with or without suramin, RB-2, U0126, and Y27632. The intracellular distribution of pERK and ROCK-I was examined in the presence of Ap4A or Ap3A (100 μM) with U0126 and Y27632 (100 nM). Results. In the presence of Ap4A, U0126, Y27632, AG1478, and (−)-blebbistatin, reduced the migration rate compared to the effect of Ap4A alone (P < 0.0001, P < 0.001, P < 0.01, and P < 0.1 versus Ap4A, respectively). In the presence of Ap3A 100 μM, U0126 and Y27632 accelerated the migration rate when compared with the effect of Ap3A alone, whereas AG1478 and (−)-blebbistatin (P < 0.0001 versus Ap3A) slowed the migration rate. Western blot assays demonstrated that both dinucleotides activated the ERK1/2 pathway but only Ap4A activated the ROCK-I pathway. The intracellular distribution of pERK1/2 and ROCK-I reflected cross-talk between these two pathways. Conclusions. The activation of the Ap4A/P2Y2 receptor, accelerates corneal epithelial cell migration during wound healing with the activation of MAPK and cytoskeleton pathways, whereas activation of the Ap3A/P2Y6 receptor signals only the MAPK pathway.
Project number: 238
Herramientas audiovisuales online y protocolos en la formación, adaptación y gestión de lentes de contacto. Un modelo innovador en la Clínica Universitaria de Optometría de la UCM
(2018) Carballo Álvarez, Jesús; Batres Valderas, Laura; Padrino Natividad, Esther; Rodríguez-Lafora Lorente, María; Serramito Blanco, María; Martín Prieto, Marina; Niño Rueda, Aranzazu; Niño Rueda, Cristina; Álvarez Rojas, David; Bartolomé Bartolomé, Gema; Peral Cerda, María Asunción; Carpena Torres, Carlos; Bella Gala, Rafael; Carracedo Rodríguez, Juan Gonzalo; González Blanco, Félix; García Alonso, Zoe Alexandra; Sánchez Pérez, María Isabel
Con fines docentes y asistenciales, incluye Videos sobre manejo y limpieza de distintos tipos de lentes de contacto. Para la correcta formación de los estudiantes incluye varios manuales sobre el estudio ocular previo a la adaptación. Con fines asistenciales incorpora Material para acompañar la adaptación y entrega de las lentes de contacto. Para mejorar la gestión, incluye un Video-tutorial y los protocolos creados para los pedidos y gestión de las lentes de contacto.
Contact Lenses as Drug Delivery System for Glaucoma: A Review
(Applied sciences, 2020) Peral Cerda, María Asunción; Martínez Águila, Alejandro; Pastrana Robles, Cristina; Huete Toral, Fernando; Carpena Torres, Carlos; Carracedo Rodríguez, Juan Gonzalo
Glaucoma is an optical neuropathy associated to a progressive degeneration of retinal ganglion cells with visual field loss and is the main cause of irreversible blindness in the world. The treatment has the aim to reduce intraocular pressure. The first therapy option is to instill drugs on the ocular surface. The main limitation of this is the reduced time of the drug staying on the cornea. This means that high doses are required to ensure its therapeutic effect. A drug-loaded contact lens can diffuse into the post lens tear film in a constant and prolonged flow, resulting in an increased retention of the drug on the surface of the cornea for up to 30 min and thus providing a higher drug bioavailability, increasing the therapeutic efficacy, reducing the amount of administered drug, and thereby provoking fewer adverse events. Several different systems of drug delivery have been studied in recent decades; ranging from more simple methods of impregnating the lenses, such as soaking, to more complex ones, such as molecular imprinting have been proposed. Moreover, different drugs, from those already commercially available to new substances such as melatonin have been studied to improve the glaucoma treatment efficacy. This review describes the role of contact lenses as an innovative drug delivery system to treat glaucoma.