Person:
Carracedo Rodríguez, Juan Gonzalo

First Name

Juan Gonzalo

Last Name

Carracedo Rodríguez

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Óptica y Optometría

Department

Optometría y Visión

Area

Optica

Identifiers

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Search Results

Now showing 1 - 10 of 78

Dual-Mode Gold Nanoparticle-Based Method for Early Detection of Acanthamoeba
(MDPI, 2022-11-28) Pastrana, Cristina; Guerreiro, Joana Rafaela L.; Elumalai, Monisha; Carpena Torres, Carlos; Crooke, Almudena; Carracedo Rodríguez, Juan Gonzalo; Prado, Marta; Huete Toral, Fernando
Acanthamoeba keratitis is an aggressive and rapidly progressing ocular pathology whose main risk factor is the use of contact lenses. An early and differential diagnosis is considered the main factor to prevent the progression and improve the prognosis of the pathology. However, current diagnosis techniques require time, complex and costly materials making an early diagnosis challenging. Thus, there is a need for fast, accessible, and accurate methods for Acanthamoeba detection by practitioners for timely and suitable treatment and even for contact lens user as preventive diagnosis. Here, we developed a dual-mode colorimetric-based method for fast, visual, and accurate detection of Acanthamoeba using gold nanoparticles (AuNPs). For this strategy, AuNPs were functionalized with thiolated probes and the presence of target Acanthamoeba genomic sequences, produce a colorimetric change from red to purple. This approach allows the detection of 0.02 and 0.009 μM of the unamplified Acanthamoeba genome by the naked eye in less than 20 min and by color analysis using a smartphone. Additionally, real samples were successfully analyzed showing the potential of the technology considering the lack of point-of-care tools that are mostly needed.
Signs and Symptoms of Dry Eye in Keratoconus Patients Before and After Intrastromal Corneal Rings Surgery
(Taylor & Francis, 2017) Carracedo Rodríguez, Juan Gonzalo; Recchioni, Alberto; Alejandre Alba, Nicolás; Martín Gil, Alba; Batres Valderas, Laura; Jiménez Alfaro-Morote, Ignacio; Pintor, Jesús
Purpose: Based on the relationship between keratoconus and dry eye, the aim of this study was to evaluate changes in signs and symptoms of dry eye in keratoconus patients before and after intrastromal corneal ring surgery. Methods: Fifteen keratoconus patients were enrolled in Fundación Jiménez-Díaz of Madrid and University Clinic of Optometry of the Universidad Complutense de Madrid (Madrid, Spain). Tear break up time (TBUT), Schirmer test without anesthesia, corneal staining, diadenosine tetraphosphate (Ap4A) concentration, and ocular surface disease index (OSDI) were evaluated. Impression cytology combined with laser confocal microscopy was performed to evaluate goblet cell density, mucin cloud height (MCH), and cell layer thickness (CLT). All measurements were performed before (pre) surgery, 1 month (post) and 6 months after surgery (post6m). Results: We found no statistical differences in time in Schirmer test, TBUT, and corneal staining. OSDI scores were 44.96 ± 8.65, 26.30 ± 6.79, and 19.31 ± 4.28 for (pre), (post), and (post6m) surgery, respectively (p < 0.001). Impression cytology showed a decrease in cell density at (post6m) compared with presurgery (47.36 ± 35.15 cells/mm2 and 84.88 ± 32.08 cells/mm2, respectively, p = 0.04). At post6m, the MCH increased compared with presurgery values (13.97 ± 4.26 µm and 6.77 ± 2.51 µm, respectively, p < 0.001). There was a statistically significant increase in CLT in time. Ap4A tear concentrations were lower post6m than presurgery (1.02 ± 0.65 and 2.56 ± 1.10 µM, respectively, p < 0.001). Conclusion: Intrastromal corneal ring surgery induces changes improving dry eye symptoms but no changes were found in signs of dry eye after surgery in keratoconus patients except for the MCH that increases drastically. More studies are needed to clarify the reason of its improvement.
PhDAY 2020 -FOO (Facultad de Óptica y Optometría)
(Facultad de Óptica y Optometría (UCM), 2020) Carpena Torres, Carlos; Pintor, Jesús; Pérez de Lara, María Jesús; Toral, Fernando; Crooke, Almudena; Pastrana, Cristina; Carracedo Rodríguez, Juan Gonzalo; Cayuela López, Ana; Sorzano Sánchez, Óscar; Charbel, Carla; Garzón Jiménez, Nuria; Carballo Álvarez, Jesús; Diz Arias, Elena; Fernández Jiménez, Elena; Peral Cerdá, Assumpta; Gómez Pedrero, José Antonio; Durán Prieto, Elena; López Alonso, José Manuel; Fernández Torres, Miguel Ángel; Guzmán Aránguez, Ana Isabel; Gómez Manzanares, Ángela; Vázquez Moliní, Daniel; Martínez Antón, Juan Carlos; Bernárdez Vilaboa, Ricardo; Mayorga Pinilla, Santiago; Álvarez Fernández-Balbuena, Antonio; Benítez, AntoJ.; El Youssfi, Asmae Igalla; León Álvarez, Alejandro; Palomo Álvarez, Catalina; LLedó Mayans, Victoria Eugenia; Awad Alkozi, Hanan; Sánchez Naves, Juan; Martínez Alberquilla, Irene; García Montero, María; Ruiz Alcocer, Javier; Madrid Costa, David; Martínez Florentín, Gema; Papas, Eric B.; Medrano Muñoz, Sandra Milena; Molina, Nancy; Jurado, Sandra; Oliveiros López, Juan; Platero Alvarado, Nadiuska Cristine; Garrido Mercado, Rafaela; Pérez Garmendia, Carlos; Antona Peñalba, Beatriz; Barrio de Santos, Ana Rosa; González Pérez, Mariano; Pérez Garmendia, Carlos; Serramito Blanco, María; Privado Aroco, Ana; Almalki, Wael; Bodas Romero, Julia; Ouzzani, Mohamed; Paune, Jaume; Calderón García, Raquel; Pitarch Velasco, Aida; Cebrián, José Luis; Sánchez Pérez, Isabel; García Rojo, Marta María; Bonnin Arias, Cristina; Sánchez Ramos, Celia; Gutiérrez Jorrín, Sara Carmen; Rodríguez Alonso, Xabier; Laucirica Sáenz, Gorka; Arranz Márquez, Esther; Alonso Castellanos, Miriam; Teus Guezala, Miguel Ángel; Hernández Verdejo, José Luis; Mármol Errasti, Esther; Martín García, Beatriz; Arriola Villalobos, Pedro; Gómez de Liaño, Rosario; Mínguez Caro, N; Orduña Azcona, Javier; Navarro Gil, Francisco Javier; Huete Toral, Fernando; Rodríguez Pomar, Candela; Pastrana Robles, Cristina; Martínez Águila, Alejandro; Martín Gil, Alba; Tomé de la Torre, Miguel Ángel
Por cuarto año consecutivo los doctorandos de la Facultad de Óptica y Optometría de la Universidad Complutense de Madrid cuentan con un congreso propio organizado por y para ellos, el 4º PhDAY- FOO. Se trata de un congreso gratuito abierto en la que estos jóvenes científicos podrán presentar sus investigaciones al resto de sus compañeros predoctorales y a toda la comunidad universitaria que quiera disfrutar de este evento. Apunta en tu agenda: el 15 de octubre de 2020. En esta ocasión será un Congreso On-line para evitar que la incertidumbre asociada a la pandemia Covid-19 pudiera condicionar su celebración.
Signs and Symptoms of Dry Eye in Keratoconus Patients: A Pilot Study
(Taylor & Francis, 2015-11) Carracedo Rodríguez, Juan Gonzalo; Recchioni, Alberto; Alejandre Alba, Nicolás; Martín Gil, Alba; Crooke, Almudena; Jiménez Alfaro-Morote, Ignacio; Pintor, Jesús
Purpose: To compare signs and symptoms of dry eye in keratoconus (KC) patients versus healthy subjects. Methods: A total of 15 KC patients (KC group, n = 15 eyes) and 16 healthy subjects (control group, 16 eyes) were enrolled in this study. The Schirmer I test with no anesthetic, tear break-up time (TBUT), corneal staining characteristics, and ocular surface disease index (OSDI) scores were evaluated for both groups. Impression cytology, combined with/scanning laser confocal microscopy (LCM), was performed to evaluate goblet cell density, mucin cloud height (MCH), and goblet cell layer thickness (CLT). Finally, tear concentrations of di-adenosine tetraphosphate (Ap4A) were assessed. Results were statistically analyzed using Shapiro–Wilk and non-parametric Wilcoxon rank sum tests. Statistical significance was set at p < 0.05. Results: KC patients had lower tear volumes and greater corneal staining than did healthy subjects (p < 0.05). OSDI scores were 44.96 ± 8.65 and 17.78 ± 6.50 for the KC and control groups, respectively (p < 0.05). We found no statistically significant differences in TBUT between groups. Impression cytology revealed lower goblet cell densities in KC group patients versus control group subjects (84.88 ± 32.98 and 128.88 ± 50.60 cells/mm,2 respectively, p < 0.05). There was a statistically significant reduction in MCH and CLT in KC group patients compared with control group subjects. Ap4A tear concentrations were higher in KC group patients than in control group subjects (2.56 ± 1.10 and 0.15 ± 0.12 µM, respectively, p < 0.05). Conclusions: The parameters evaluated in this study indicate that KC patients suffer greater symptoms of dry eye and greater tear instability, primarily due to the decreased mucin production in their tears, than do healthy patients with no KC.
Epithelium-Off vs. transepithelial corneal collagen crosslinking in progressive keratoconus: 3 years of follow-up
(Spanish General Council of Optometrists, 2020-09-01) Arance Gil, Ángeles; Villa Collar, César; Pérez Sánchez, Belén; Carracedo Rodríguez, Juan Gonzalo; Gutiérrez Ortega, Ángel Ramón
Purpose: To compare the efficacy of epithelium-off corneal collagen crosslinking (CXL) with transepithelial CXL in patients with progressive keratoconus with a follow-up of 3 years, taking into account the patients’ age and the location of the corneal ectasia. Methods: In this prospective study participated 64 eyes with progressive keratoconus were included in this long-term study, of which 31 eyes were treated by epithelium-off CXL and 33 by transepithelial CXL. All of the patients with a follow-up of 36 months were evaluated for visual variables (corrected distance visual acuity (CDVA), corneal aberrations, and corneal densitometry), structure variables (astigmatism, keratometry, corneal asphericity, maximum posterior elevation, corneal thickness, and corneal volume), and keratoconus index variables. Results: After corneal CXL, CDVA improved significantly in both central and paracentral keratoconus, with greater improvement in the centrals (p = 0.001), asphericity at 6 mm improved in central keratoconus (p = 0.047). In the epi-off group, there was a significant improvement in coma-like (p = 0.038), higher-order aberrations (p = 0.036), asphericity at 8 mm (p = 0.049), asphericity at 10 mm (p = 0.049), and index of surface variance (p = 0.049). Conclusion: Although both techniques halted and stabilized the progression of keratoconus, epithelium-off CXL was more effective. In addition, after the corneal CXL, there was a greater degree of regularization of the corneal surface and, therefore, a greater improvement in the CDVA with central keratoconus than with paracentral keratoconus.
Melatonin-Eluting Contact Lenses Effect on Tear Volume: In Vitro and In Vivo Experiments
(MDPI, 2022-05) Serramito Blanco, María; Pereira da Mota, Ana Filipa; Carpena Torres, Carlos; Huete Toral, Fernando; Álvarez Lorenzo, Carmen Isabel; Carracedo Rodríguez, Juan Gonzalo
Background: The purpose of this study was to synthesize melatonin-eluting contact lenses (CLs) and evaluate both the ocular kinetics of the released melatonin and its effect on tear volume and intraocular pressure. Methods: In vitro, melatonin-eluting CLs were synthesized by using non-functionalized (HEMA) and functionalized (HEMA/APMA) monomers. In vivo, a short-term prospective and randomized study was performed on 15 rabbits divided into two groups: 12 rabbits wearing functionalized CLs and 3 rabbits without CLs as a control. The melatonin levels in tears, aqueous humor, vitreous body and retina, tear volume, and intraocular pressure were measured for 8 h. Results: In vitro, both monomers did not show differences in terms of melatonin loading and release (p ≥ 0.05). In vivo, the melatonin concentration was elevated in tears and aqueous humor after 2 and 4 h of wearing CLs, respectively (p < 0.05). Additionally, the CLs increased tear volume for 2 h (p < 0.05). Conclusions: The melatonin-eluting CLs released their content over the ocular surface for at least 2 h, which was associated with a secretagogue effect on tear volume. However, the increased amount of melatonin found in the aqueous humor had no effect on intraocular pressure.
Increased Levels of Diadenosine Polyphosphates in Dry Eye
(The Association for Research in Vision and Ophthalmology, Inc., 2006-09) Peral Cerdá, Assumpta; Carracedo Rodríguez, Juan Gonzalo; Acosta Boj, Mª Carmen; Gallar Martínez, Juana; Pintor, Jesús
Purpose. To analyze the levels of the diadenosine polyphosphates Ap4A and Ap5A in tears, in a set of control subjects and in groups of symptomatic and nonsymptomatic persons with dry eye. Methods. Ninety-seven subjects participated in the study. The subjects were divided into five experimental groups: control subjects; symptomatic patients with normal tear secretion; symptomatic patients with low tear secretion; forced blink; and corneal mechanical stimulation provided by a gas esthesiometer. The Schirmer I test was used to measure and collect tear secretions from each subject. All samples were processed by high pressure liquid chromatography (HPLC) and their Ap4A and Ap5A levels determined. Results. The levels of Ap4A and Ap5A in tears were greater in all symptomatic patients than in control subjects, especially in symptomatic subjects with low tear secretion. Within the symptomatic subjects with normal tear secretion, significant differences in concentrations of Ap4A and Ap5A were found between men and women. In the forced blink experiments, concentrations of the Ap4A and Ap5A rose with increasing blink frequency. When the cornea was mechanically stimulated, the levels of Ap4A and Ap5A rose significantly during both moderate and high-flow rate tests. Conclusions. The increased levels of Ap4A and Ap5A in tears of patients with dry eye allow these dinucleotides to be used as objective biomarkers in dry eye conditions.
A review of international medical device regulations: Contact lenses and lens care solutions
(Elsevier, 2018-11-14) Zaki, Marina; Pardo, Jesús; Carracedo Rodríguez, Juan Gonzalo
Medical devices are under strict regulatory oversight worldwide and such regulations prioritise patient safety and efficacy over anything else. Contact lenses fall under the medical device category - a result of direct contact with the eye. Equally regulated are the contact lens care product solutions, which include cleaning and maintenance solutions and lubricating and rewetting drops. In the USA, it is the FDA Centre for Devices and Radiological Health (CDRH) overseeing the regulations of medical devices, since 1976. In the European Union, it is the EU Commission responsible for regulating devices in Member States. The categorisation of contact lenses into medical devices is based on their inherent risk to the wearer. Contact lenses are subject to crucial regulatory oversight from concept to clinical evaluation, clinical investigations through to the finished lens product, and finally, strict conditions associated with their marketing approval including post-marketing surveillance. The physiochemical and manufacturing testing, such as biocompatibility testing alongside pre-clinical stability, sterility and microbiological testing are just some of the essential testing lenses must endure. Only through understanding the inherent risks and potential complications that can arise from contact lens wear, can one truly appreciate the need to adhere to strict regulations. The challenge however, lies in the need for more standardised regulations and flexible approaches, ensuring innovative device technologies reach patients in a timely manner without compromising public health and safety. This review highlights some key requirement, differences and similarities between the FDA and EU administrations in the approval of contact lenses.
Presence of melatonin in human tears
(Spanish General Council of Optometrists, 2016-04-13) Carracedo Rodríguez, Juan Gonzalo; Carpena, Carlos; Concepción, Pablo; Díaz, Victor; García-García, Miguel; Jemnic, Nahla; Lledó, Victoria Eugenia; Martín, Marina; Pastrana, Cristina; Pelissier, Raquel; Veselinova, Albena; Wang, Xiaoyu; Pintor, Jesús
Dipyridamole activates adenosine A2B receptor and AMPK/cAMP signaling and promotes myogenic differentiation of myoblastic C2C12 cells
(Frontiers Media, 2023-09-12) Marco Bonilla, Miguel; Herencia , Raquel; Fresnadillo, María; Huete Toral, Fernando; Carracedo Rodríguez, Juan Gonzalo; Largo, Raquel; Herrero Beaumont , Gabriel; Mediero, Aranzazú
Introduction: Sarcopenia is defined as a loss of muscle mass and strength. ATP homeostasis is crucial during myogenesis. We determined how the purinergic system modulates myogenesis using dipyridamole (blocks adenosine taken up by the cells) and tenofovir (inhibits ATP release) in a myoblast cell line. Methods: C2C12 cells were differentiated in the presence/absence of tenofovir/dipyridamole, with/without the A2B selective inhibitor PSB-603. Extra-/intracellular nucleotides were examined via HPLC. The expression of muscle differentiation proteins (Pax7, Mif5, MyoD, MyoG, and MHC), PKA/CREB, adenosine receptors (A1, A2A, A2B, and A3), ATP-channel pannexin-1 and the P2X7 receptor was analyzed via WB and RT-PCR. cAMP and AMPK activation was measured. Results: Tenofovir increased intracellular ATP and reduced extracellular adenosine, decreasing Pax7 expression and increasing MHC expression prematurely. Dipyridamole increased intracellular AMP and extracellular adenosine, counteracting the premature myogenesis promoted by tenofovir. All adenosine receptors were expressed during differentiation with dipyridamole, increasing A2B expression. Tenofovir maintained inactive AMPK and decreased cAMP levels, as well as PKAα and pCREB expression, which were recovered with dipyridamole. Discussion: Adenosine and ATP act as mediators in muscle myogenesis. The blockade of ATP release by tenofovir promotes premature myogenesis, with dipyridamole counteracting the premature differentiation promoted by tenofovir via the adenosine A2B receptor and cAMP/AMPK pathways. Therefore, dipyridamole might be of interest as a therapeutic approach in sarcopenia. Copyright © 2023 Marco-Bonilla, Herencia, Fresnadillo, Huete-Toral, Carracedo, Largo, Herrero-Beaumont and Mediero.