Objective. To investigate refractive development and prevalence of myopia in children aged 3-6 years in Hebei Province, China, and to explore the developmental law of refraction, so as to clinically guide the prediction and intervention of myopia. Methods. In May 2019, a total of 6120 people were inspected in 68 kindergartens in 11 cities in Hebei Province. Child refractive refraction was checked under noncycloplegia using a handheld binocular vision screener (SW-800, SUOER, Tianjin, China). Axial length (AL) and corneal radius of curvature (CR) were measured using an ocular biometry (IOLMaster 500, Carl Zeiss, Germany). Myopia was defined as spherical equivalent SE ≤ − 0.75   D . Results. A total of 5506 children aged 3-6 years met the criteria and were included in the statistical analysis. The prevalence of myopia was 3.49% (1.93% at age 3, 2.90% at age 4, 3.78% at age 5, and 3.88% at age 6). Overall, the mean SE was + 0.67 ± 1.05   D ( + 0.81 ± 1.00   D at age 3, + 0.79 ± 1.05   D at age 4, + 0.67 ± 1.08   D at age 5, and + 0.13 ± 1.01   D at age 6); the mean CR was 7.76 ± 0.26   mm ( 7.78 ± 0.26   mm at age3, 7.75 ± 0.25   mm at age 4, 7.77 ± 0.26   mm at age 5, and 7.76 ± 0.25   mm at age 6); the mean AL was 22.31 ± 0.73   mm ( 21.98 ± 0.63   mm at age 3, 22.12 ± 0.69   mm at age 4, 22.34 ± 0.73   mm at age 5, and 22.49 ± 0.73   mm at age 6). Conclusions. Prevalence of myopia increases with age in children aged 3-6 years in Hebei, China. With the increase of age, CR is basically stable, and AL increases gradually. AL/CR, which is closely related to SE, can be used as an indicator to predict myopia and guide clinical work.

The Gp2 domain is a 45 amino‐acid scaffold that has been evolved for specific, high‐affinity binding towards multiple targets and was proven useful in molecular imaging and biological antagonism. It was hypothesized that Gp2 may benefit from increased hydrophilicity for improved physiological distribution as well as for physicochemical robustness. We identified seven exposed hydrophobic sites for hydrophilic mutations and experimentally evaluated single mutants, which yielded six mutations that do not substantially hinder expression, binding affinity or specificity (to epidermal growth factor receptor), and thermal stability. Eight combinations of these mutations improved hydrophilicity relative to the parental Gp2 clone as assessed by reverse‐phase high‐performance liquid chromatography (p < 0.05). Secondary structures and refolding abilities of the selected single mutants and all multimutants were unchanged relative to the parental ligand. A variant with five hydrophobic‐to‐hydrophilic mutations was identified with enhanced solubility as well as reasonable binding affinity ( K d = 53–63 nM), recombinant yield (1.3 ± 0.8 mg/L), and thermal stability ( T m = 53 ± 3°C). An alternative variant with a cluster of three leucine‐to‐hydrophilic mutations was identified with increased solubility, nominally increased binding affinity ( K d = 13–28 nM) and reasonable thermal stability ( T m = 54.0 ± 0.6°C) but reduced yield (0.4 ± 0.3 mg/L). In addition, a ≥7°C increase in the midpoint of thermal denaturation was observed in one of the single mutants (T21N). These mutants highlight the physicochemical tradeoffs associated with hydrophobic‐to‐hydrophilic mutation within a small protein, improve the solubility and hydrophilicity of an existent molecular imaging probe, and provide a more hydrophilic starting point for discovery of new Gp2 ligands towards additional targets.

We aimed to evaluate the clinical effect and safety of orthokeratology in controlling the development of myopia. We assessed the changes in visual acuity, diopter change, axial length, corneal endothelium count, intraocular pressure, and corneal Q value in 30 adolescents with 60 years of wearing an orthokeratology lens. In this study, no significant difference was observed between the naked eye vision and corrected visual acuity before wearing the lens (t = –0.23, P = 0.59); furthermore, no significant difference was observed in diopter, axial length, corneal endothelium count, and intraocular pressure 1 year before and after wearing the lens (t = 1.24, P = 0.45; t = –0.89, P = 0.25; t = –0.43, P = 0.57; t = 1.43, P = 0.61); by contrast, there was a significant difference in the corneal Q value before and after wearing the lens (t = –8.37, P = 0.001). These results suggest that the fluorosilicone acrylic breathable material corneal orthopedic lens is safe and effective in controlling myopia, and has little effect on the physiology of the eye.