The impact of overnight orthokeratology on accommodative response in myopic subjects

This study aimed to evaluate the effects of two months of orthokeratology (OK) treatment in the accommodative response of young adult myopes. Twenty eyes (21.8 ± 1.8 years) were fitted with the Paragon CRT® 100 LENS to treat myopia between −1.00 and −2.00 D. Low- and high-contrast visual acuity (LCDVA and HCDVA), central objective refraction, light disturbance (LD), and objective accommodative response (using the Grand Seiko WAM-5500 open-field autorefractometer coupled with a Badal system) were measured at baseline (BL) before lens wear and after 1, 15, 30, and 60 nights of OK. Refractive error correction was achieved during the first fifty days of OK lens wear, with minimal changes afterwards. LD analysis showed a transient increase followed by a reduction to baseline levels over the first 30 nights of treatment. The accommodative response was lower than expected for all target vergences in all visits (BL: 0.61 D at 1.00 D to 0.96 D at 5.00 D; 60 N: 0.36 D at 1.00 D to 0.79 D at 5.00 D). On average, the accommodative lag decreases over time with OK lens wear. However, these differences were not statistically significant (p > 0.050, repeated-measures ANOVA and Friedman test). This shows that overnight OK treatment does not affect objectively measured the accommodative response of young, low myopic eyes after two months of treatment stabilization.This research was supported by the Portuguese Foundation for Science and Technology (FCT) PTDC/FIS-OPT/0677/2014, the Strategic Funding UID/FIS/04650/2013 at Center of Physics, UMinho, and predoctoral grant SFRH/BD/136684/2018 to A.A.S

Retinal response of low myopes during orthokeratology treatment

The aim of this study was to evaluate the changes in retinal activity during orthokeratology (OK) treatment in 20 myopic eyes. Pattern electroretinography (PERG) and visual evoked potential (VEP) were assessed with the RETI-port/scan21 (Roland Consult, Wiesbaden, Germany). Measurements were taken at baseline (BL) and 1 night (1N), 15 nights (15N), 30 nights (30N), and 60 nights (60N) of OK lens wear. Repeated measures analysis of variance (ANOVA) and the Friedman test were used. Twenty eyes (23.20 ± 3.46 years, 70% female) with visual acuity ≤ 0.00 logMAR in post-treatment showed that despite a slight increase in retinal and cortical response amplitude, observed with both PERG and VEP, respectively, immediately after the initial treatment, these differences found were not statistically significant during the 60 days of OK treatment, despite a statistically significant increase in N95 response with PERG. This shows that retinal and cortical visual-related electrical activity is maintained or slightly increased during OK treatment.This research was supported by the Portuguese Foundation for Science and Technology (FCT) PTDC/FIS-OPT/0677/2014, the Strategic Funding UID/FIS/04650/2013 at Center of Physics, UMinho, and predoctoral grant SFRH/BD/136684/2018 to A.A.

Testing drug release from medicated contact lenses: the missing link to predict in vivo performance

Contact lenses (CLs) offer a wide variety of advantages as ocular drug-releasing platforms, but the feasibility of medicated CL development is constrained by numerous scientific, technological, and regulatory challenges. One main difficulty is the setting of release rate specifications for each drug, since at present there are no standardized in vitro release models that can appropriately predict the performance of drug-eluting CLs once placed onto the eye. CL-adapted release tests may provide knowledge on how the drug release pattern should perform in vivo to trigger and maintain the therapeutic effects for both anterior and posterior ocular tissues. Moreover, in vitro release tests are valuable tools for quality assessment during production and to investigate the effect of a change in composition or process variables. This review aims to shed light on biorelevant ways of evaluating in vitro drug release from CLs and the feasibility of establishing in vitro-in vivo correlations (IVIVC) to predict in vivo performance. First, general guidelines and Pharmacopeia release tests for topical ophthalmic formulations as well as in vitro release tests implemented for drug-CLs in the last two decades are analyzed. Then, development of an appropriate method to investigate IVIVC is attempted from the few papers simultaneously reporting in vitro release profiles and either in vivo release or therapeutic response. Finally, key points to be considered for in vitro testing drug release from a medicated CL are suggested to pave the way to the clinical arenaThis project is funded by the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Actions grant agreement N° 813440 (ORBITAL–Ocular Research by Integrated Training And Learning). The work was also partially supported by MCIN [PID2020-113881RB-I00/AEI/10.13039/501100011033] Spain, Xunta de Galicia [ED431C 2020/17], and FEDERS

Phosphorylcholine-Based Contact Lenses for Sustained Release of Resveratrol: Design, Antioxidant and Antimicrobial Performances, and In Vivo Behavior

Design of advanced contact lenses (CLs) demands materials that are safe and comfortable for the wearers and that preserve the normal eye microbiota, avoiding chronic inflammation and biofilm development. This work aimed to combine the natural antibiofouling phosphorylcholine and the antioxidant and prebiotic resveratrol as integral components of CLs that may have the additional performance of preventing oxidative-stress related eye diseases. Different from previous uses of 2-methacryloyloxyethyl phosphorylcholine (MPC) as coating, we explored the feasibility of adding MPC at high proportions as a comonomer of 2-hydroxyethyl methacrylate (HEMA)-based hydrogels while still allowing for the loading of the hydrophobic resveratrol. Homogeneous distribution of MPC along the hydrogel depth (confirmed by Raman spectroscopy) notably increased solvent uptake and the proportion of free water while it decreased Young’s modulus. Relevantly, MPC did not hinder the uptake of resveratrol by CLs (>10 mg/g), which indeed showed network/water partition coefficients of >100. Protocols for CLs sterilization and loading of resveratrol under aseptic conditions were implemented, and the effects of tear proteins on resveratrol release rate were investigated. CLs sustained resveratrol release for more than 24 h in vitro, and sorption of albumin onto the hydrogel, although attenuated by MPC, slowed down the release. The combination of MPC and resveratrol reduced P. aeruginosa and S. aureus growth as tested in a novel hydrogel disk-agar interface biofilm growth setup. The developed CLs showed excellent anti-inflammatory properties and biocompatibility in in ovo and rabbit tests and provided higher and more prolonged levels of resveratrol in tear fluid, which favored resveratrol biodistribution in anterior and posterior eye segments compared to eye drops. Correlations between the release profiles of resveratrol in vitro and in vivo were assessed. Relevantly, the CLs preserved the antioxidant properties of resveratrol during the entire 8 h of wearing. In sum, CLs prepared with high proportion in MPC may help address safety and comfort requirements while having drug releasing capabilitiesThe authors are grateful to Mabel Loza and Cristina Val García, from BioFarma Research Group (USC GI-1685), for their help in the UPLC experiment, and to Luis Díaz-Gómez for advice in the anti-inflammatory tests. M.V.-L. acknowledges Xunta de Galicia (Consellería de Cultura, Educación e Ordenación Universitaria) for a predoctoral research fellowship [Grant ED481A-2019/120]. A.F.P.-d.-M. is an ESR of the European Union’s Horizon 2020 research and innovation program under Marie Skłodowska-Curie Actions Grant Agreement 813440 (ORBITAL-Ocular Research by Integrated Training and Learning)S

In vitro–in vivo correlation of drug release profiles from medicated contact lenses using an in vitro eye blink model

There is still a paucity of information on how in vitro release profiles from drug-loaded contact lenses (CLs) recorded in 3D printed eye models correlate with in vivo profiles. This work aims to evaluate the release profiles of two drug-loaded CLs in a 3D in vitro eye blink model and compare the obtained results with the release in a vial and the drug levels in tear fluid previously obtained from an animal in vivo study. In vitro release in the eye model was tested at two different flow rates (5 and 10 µL/min) and a blink speed of 1 blink/10 s. Model CLs were loaded with two different drugs, hydrophilic pravastatin and hydrophobic resveratrol. The release of both drugs was more sustained and lower in the 3D eye model compared to the in vitro release in vials. Interestingly, both drugs presented similar release patterns in the eye model and in vivo, although the total amount of drugs released in the eye model was significantly lower, especially for resveratrol. Strong correlations between percentages of pravastatin released in the eye model and in vivo were found. These findings suggest that the current 3D printed eye blink model could be a useful tool to measure the release of ophthalmic drugs from medicated CLs. Nevertheless, physiological parameters such as the composition of the tear fluid and eyeball surface, tear flow rates, and temperature should be optimized in further studiesOpen Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This project was funded by the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Actions grant agreement N° 813440 (ORBITAL–Ocular Research by Integrated Training And Learning). The work was also partially supported by MCIN [PID 2020-113881RB-I00/AEI/10.13039/501100011033], Spain, Xunta de Galicia [ED431C 2020/17], FEDER, and the Hong Kong Special Administrative Region Government and InnoHK. M. Vivero-Lopez acknowledges Xunta de Galicia (Consellería de Cultura, Educación e Ordenación Universitaria) for a predoctoral research fellowship [ED481A-2019/120]. P. Garg acknowledges the support of the Collaborative Research and Training Experience (CREATE) Program awarded by the Natural Sciences and Engineering Research Council of Canada (NSERC)S

Valorization of sugarcane by-products through synthesis of biogenic amorphous silica microspheres for sustainable cosmetics

Ashes from sugarcane by-product incineration were used to synthesize silica powders through alkaline hot extraction, followed by ethanol/acid precipitation or the sol–gel method. Both production methods allowed amorphous spherical silica microparticles with sizes ranging from 1–15 μm and 97% purity to be obtained. Water absorption ranged from 135–155 mL/100 g and 150–250 mL/100 g for precipitated silica and silica gel, respectively, while oil absorption ranged from 305 to 390 and from 250 to 350 mL/100 g. The precipitation with ethanol allowed the recovery of 178 g silica/kg ash, with a lab process cost of EUR 28.95/kg, while the sol-gel process showed a yield of 198 g silica/kg ash with a cost of EUR 10.89/kg. The experimental data suggest that ash from sugarcane by-products is a promising source to be converted into a competitive value-added product, minimizing the environmental impact of disposal problems.info:eu-repo/semantics/publishedVersio

Atividade física, qualidade de vida e depressão durante a gravidez

This study examines physical activity patterns among women, from pre-pregnancy to the second trimester of pregnancy, and the relationship between physical activity status based on physical activity guidelines and health-related quality of life (HRQoL) and depression over pregnancy. 56 healthy pregnant women self reported physical activity, HRQoL and depression at 10-15 and 19-24 weeks of pregnancy and physical activity before pregnancy. Whereas vigorous leisure physical activity decreased after conception, moderate leisure physical activity and work related physical activity remained stable over time. The prevalence of recommended physical activity was 39.3% and 12.5% in the 1st and 2nd trimesters of pregnancy respectively, and 14.3% pre-pregnancy. From the 1st to the 2nd pregnancy trimester, most physical HRQoL dimensions scores decreased and only mental component increased, independently of physical activity status. No changes in mean depression scores were observed. These data suggest that physical activity patterns change with pregnancy and that physical and mental components are differentially affected by pregnancy course, independently of physical activity status.Este estudo examina os padrões de atividade física antes da concepção até o segundo trimestre de gravidez e a relação entre o nível de atividade física, com base nas recomendações de atividade física, a qualidade de vida relacionada à saúde (QVRS) e depressão ao longo da gravidez. Cinquenta e seis grávidas saudáveis reportaram nível de atividade física, QVRS e depressão às 10-15 e 19-24 semanas de gravidez, além de atividade física antes da concepção. Enquanto a atividade física vigorosa no lazer diminuiu depois da concepção, as atividades físicas moderadas no lazer e no trabalho mantiveram-se estáveis. A prevalência de atividade fí- sica recomendada foi de 39,3%, 12,5% e 14,3% antes, no primeiro e no segundo trimestres de gravidez, respectivamente. Independentemente do estatuto de atividade física, a maior parte dos escores nas dimensões físicas da QVRS diminui do primeiro para o segundo trimestre de gestação, e apenas o componente mental aumenta. Não se verificaram alterações nos escores médios de depressão. Estes dados sugerem que, com a gravidez, há alteração nos padrões de atividade física; além disso, os componentes físico e mental são diferentemente afetados pelo curso da gestação, independentemente do nível de atividade física