Effect of refractive status on retinal nerve fiber layer thickness in Chinese Population.

PURPOSE: To evaluate the relationship between retinal nerve fiber layer (RNFL) thickness and other related parameters measured by spectral-domain optical coherence tomography and the refractive error of eyes. METHODS: A total of 5394 subjects were enrolled in this population-based cohort study, who were divided into three groups by refractive state after they underwent a standardized ophthalmic examination: emmetropia (the absolute value should range from 0 to 0.5 D), low-moderate myopia (the absolute value of myopic error should range from 0.5 to 6 D), and high myopia (the absolute value of myopic error should be over than 6 D). R 3.6.1 software was adopted for statistical analysis. RESULTS: Two thousand five hundred fifty-two subjects (4548 eyes) were collected in this study, with an average age of 53.14 ± 10.64 years. There were significant differences among groups in average central corneal curvature, spherical equivalent, and axial length (P < 0.001). The measurements of average retinal nerve fiber layer (RNFL) were 113.95 ± 10.62 µm, 112.97 ± 11.59 µm, and 101.88 ± 15.67 µm, respectively, in the emmetropia, low-moderate, and high myopia groups (P < 0.001). Meanwhile, there was a decreasing trend of cup area, cup volume, disc area, and rim area in the high myopia group compared with the emmetropia group (P < 0.001). CONCLUSION: The measurements of RNFL thickness vary greatly with refractive error, and this study indicated that it is of great significance for the accurate diagnosis of glaucoma to establish an individualized RNFL thickness database.

Factors Associated with Changes in Peripapillary Retinal Nerve Fibre Layer Thickness in Healthy Myopic Eyes.

Myopic people face an elevated risk of primary open angle glaucoma. Changes in the fundus in people with high myopia often lead to misdiagnosis of glaucoma, as this condition has many clinical signs in common with myopia, making the diagnosis of glaucoma more challenging. Compared to reduction of the visual field, a decrease in retinal nerve fibre layer (RNFL) thickness occurs earlier in glaucoma, which is widely considered useful for distinguishing between these conditions. With the development of optical coherence tomography (OCT), RNFL thickness can be measured with good reproducibility. According to previous studies, this variable is not only affected by axial length but also related to the patient's age, gender, ethnicity, optic disc area, and retinal blood flow in myopia. Herein, we intend to summarize the factors relevant to the RNFL in myopia to reduce the false-positive rate of glaucoma diagnosis and facilitate early prevention of myopia.

Proteomic analysis of cPKCßII-interacting proteins involved in HPC-induced neuroprotection against cerebral ischemia of mice.

Hypoxic preconditioning (HPC) initiates intracellular signaling pathway to provide protection against subsequent cerebral ischemic injuries, and its mechanism may provide molecular targets for therapy in stroke. According to our study of conventional protein kinase C ßII (cPKCßII) activation in HPC, the role of cPKCßII in HPC-induced neuroprotection and its interacting proteins were determined in this study. The autohypoxia-induced HPC and middle cerebral artery occlusion (MCAO)-induced cerebral ischemia mouse models were prepared as reported. We found that HPC reduced 6 h MCAO-induced neurological deficits, infarct volume, edema ratio and cell apoptosis in peri-infarct region (penumbra), but cPKCßII inhibitors Go6983 and LY333531 blocked HPC-induced neuroprotection. Proteomic analysis revealed that the expression of four proteins in cytosol and eight proteins in particulate fraction changed significantly among 49 identified cPKCßII-interacting proteins in cortex of HPC mice. In addition, HPC could inhibit the decrease of phosphorylated collapsin response mediator protein-2 (CRMP-2) level and increase of CRMP-2 breakdown product. TAT-CRMP-2 peptide, which prevents the cleavage of endogenous CRMP-2, could inhibit CRMP-2 dephosphorylation and proteolysis as well as the infarct volume of 6 h MCAO mice. This study is the first to report multiple cPKCßII-interacting proteins in HPC mouse brain and the role of cPKCßII-CRMP-2 in HPC-induced neuroprotection against early stages of ischemic injuries in mice.