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1.
Biomed Opt Express ; 14(8): 4190-4204, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37799675

RESUMO

The quantitative evaluation of peripheral ocular optics is essential in both myopia research and the investigation of visual performance in people with normal and compromised central vision. We have developed a widefield scanning wavefront sensor (WSWS) capable of multidirectional scanning while maintaining natural central fixation at the primary gaze. This Shack-Hartmann-based WSWS scans along any retinal meridian by using a unique scanning method that involves the concurrent operation of a motorized rotary stage (horizontal scan) and a goniometer (vertical scan). To showcase the capability of the WSWS, we tested scanning along four meridians including a 60° horizontal, 36° vertical, and two 36° diagonal scans, each completed within a time frame of 5 seconds.

3.
Heliyon ; 6(4): e03642, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32274428

RESUMO

The objective of the present retrospective comparative cohort study was to compare the impact of wearing glasses versus an orthokeratology (Ortho-K) lens on peripheral optical properties and myopia progression in a population of South Korean children. Participants included children with myopia, between 8 and 12 years of age (n = 22 eyes), and divided into two groups: those who used glasses (Group I, n = 9) and those who used an Ortho-K lens (Group II, n = 13). Myopia progression over one year was quantified by changes in the central axial length of the eye. Keratometry and corneal aberrations on both the anterior and posterior surfaces of the eye were obtained using a Scheimpflug camera. A custom-developed Shack-Hartmann aberrometer was also used to measure peripheral aberrations across the horizontal visual field, up to 30°, and along the nasal-temporal meridian in 10-degree steps. Central axial elongation was larger in Group I (0.59 ± 0.21 mm) than in Group II (0.34 ± 0.18 mm) (P = .01). Relative peripheral spherical refractions at 10 and 20° nasally and at 10° temporally (P = 0.04, 0.049, and 0.042, respectively) relative to the fovea were positively correlated with central axial elongation in Group II. Group II exhibited an increase in peripheral ocular high order aberrations, such as horizontal coma and asymmetric trefoil. The use of Ortho-K lenses was found to slow the rate of central axis elongation in children with myopia. This effect might be related to an increase in both peripheral spherical refraction and peripheral ocular higher order aberrations with Ortho-K lens use.

4.
Eur J Pharm Biopharm ; 149: 135-144, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32007590

RESUMO

The major therapeutic strategy for acid-related gastrointestinal diseases in clinic is to reduce the excretion of gastric acid by oral administration of proton-pump inhibitors (PPIs). However, it is quite a challenge to study the oral absorption behaviors of PPIs considering their extreme instability under gastrointestinal environment. As a result, little information has been reported on PPI oral absorption so far, hindering the further development of PPI-contained oral preparations. Here, we first investigated the degradation rate of three representative PPIs, including ilaprazole, ilaprazole sodium and rabeprazole sodium. Then a modified in situ intestine absorption method in rat was established: through the temperature control by the heat exchangers, the perfusate was kept at physiological temperature only when passing through the intestine while it was maintained at 4 °C outside the intestine. Therefore PPIs could maintained sufficiently high stability under proper temperature control. Our data demonstrated that both ilaprazole and ilaprazole sodium exhibited significantly higher absorption efficiency than rabeprazole sodium did through the comparison of their apparent permeability coefficients and steady-state plasma concentrations after perfusion in the duodenum, jejunum, ileum and colon, mainly attributing to their more suitable oil-water partition coefficient. The duodenum could be the best site for the oral absorption of PPIs. Ilaprazole outperformed its sodium salt form with its stable absorption behavior in tested four intestinal segments. Furthermore, after intravenous or oral administration, ilaprazole exhibited a longer residence time and a higher accumulation in the stomach than in most of other tissues/organs. However, it was also found that the accumulation was heterogeneous and mainly located in mucosa cells of the stomach. Our further study indicated that there was no significant difference on the oral absorption efficiency of ilaprazole between female and male rats but ilaprazole underwent a faster metabolism in male rats after oral absorption. Our study provided a valuable guidance for the design of oral formulation and the optimization of PPI-contained formulations.


Assuntos
2-Piridinilmetilsulfinilbenzimidazóis/farmacocinética , Absorção Intestinal , Inibidores da Bomba de Prótons/farmacocinética , Rabeprazol/farmacocinética , 2-Piridinilmetilsulfinilbenzimidazóis/administração & dosagem , Administração Intravenosa , Administração Oral , Animais , Estabilidade de Medicamentos , Feminino , Masculino , Inibidores da Bomba de Prótons/administração & dosagem , Rabeprazol/administração & dosagem , Ratos , Ratos Sprague-Dawley , Fatores Sexuais , Temperatura , Distribuição Tecidual
5.
Ophthalmic Physiol Opt ; 38(3): 326-336, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29691930

RESUMO

PURPOSE: To characterise the impact of monofocal soft contact lens (SCL) and bifocal SCLs on refractive error, depth of focus (DoF) and orientation of blur in the peripheral visual field. METHODS: Monofocal and two bifocal SCLs, Acuvue Bifocal (AVB, Johnson & Johnson) and Misight Dual Focus (DF, CooperVision) with +2.0 D add power were modelled using a ray tracing program (ZEMAX) based on their power maps. These SCLs were placed onto the anterior corneal surface of the simulated Atchison myopic eye model to correct for -3.0 D spherical refractive error at the fovea. To quantify through-focus retinal image quality, defocus from -3.5 D to 1.5 D in 0.5 D steps was induced at each horizontal eccentricity from 0 to 40° in 10° steps. Wavefront aberrations were computed for each visual eccentricity and defocus. The retinal images were simulated using a custom software program developed in Matlab (The MathWorks) by convolving the point spread function calculated from the aberration with a reference image. The convolved images were spatially filtered to match the spatial resolution limit of each peripheral eccentricity. Retinal image quality was then quantified by the 2-D cross-correlation between the filtered convolved retinal images and the reference image. Peripheral defocus, DoF and orientation of blur were also estimated. RESULTS: In comparison with the monofocal SCL, the bifocal SCLs degraded retinal image quality while DoF was increased at fovea. From 10 to 20°, a relatively small amount of myopic shift (less than 0.3 D) was induced by bifocal SCLs compared with monofocal. DoF was also increased with bifocal SCLs at peripheral vision of 10 and 20°. The trend of myopic shift became less consistent at larger eccentricity, where at 30° DF showed a 0.75 D myopic shift while AVB showed a 0.2 D hyperopic shift and both AVB and DF exhibited large relative hyperopic defocus at 40°. The anisotropy in orientation of blur was found to increase and change its direction through focus beyond central vision. This trend was found to be less dominant with bifocal SCLs compared to monofocal SCL. CONCLUSIONS: Bifocal SCLs have a relatively small impact on myopic shift in peripheral refractive error while DoF is increased significantly. We hypothetically suggest that a mechanism underlying myopia control with these bifocal or multifocal contact lenses is an increase in DoF and a decrease in anisotropy of peripheral optical blur.


Assuntos
Lentes de Contato Hidrofílicas , Refração Ocular/fisiologia , Erros de Refração/terapia , Campos Visuais/fisiologia , Desenho de Equipamento , Fóvea Central/fisiopatologia , Humanos , Erros de Refração/fisiopatologia
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