Protective effect of leukemia inhibitory factor on light induced retinal photoreceptors damage and its mechanisms / 中华实验眼科杂志

Objective To investigate the role of leukemia inhibitory factor (LIF) on retinal photoreceptor cells and the underlying mechanism after light damage.Methods Fifty 5-6 weeks old BALB/c mice were randomly divided into normal control group (10 mice),light damage+LIF group (20 mice) and light damage+PBS group (20 mice).Four days before exposing to light,the right eye of each animal in light damage+LIF group and light damage+PBS group was injected with LIF and PBS,respectively;then the mice in the light damage+LIF group and light damage+PBS group were exposed to 4 000 lx intensity of cool white fluorescent light for 4 hours to establish the experimental model of retinal light damage.The function and morphology of retinal photoreceptor cells were detected by flash electroretinogram (fERG) and histopathological examination.Real-time PCR was used to detect the mRNA expression of Jak3,STAT3,and apoptosis-related factor Bcl-2 and Bax.The use of animals is guided by the State Science and Technology Commission's regulations on the management of experimental animals.Results The amplitudes of scotopic ERG a wave of 0.01,1,100,200,400 cd · s/m2 light in the light damage + PBS group were significantly lower than those in the normal control group and light damage + LIF group (all at P ＜ 0.05).The amplitudes of photopic ERG b wave of different color light in the light damage+PBS group were significantly lower than those in the normal control group and light damage+LIF group (all at P＜0.05).The number of photoreceptor nuclei in the light damage+PBS group was significantly lower than that in the normal control group and light damage+ LIF group (both at P＜0.05).Compared with light damage+PBS group,the relative expression of Jak3,STAT3,Bcl-2 mRNA in light damage+LIF group were significantly increased (all at P＜0.05),and the relative expression of Bax mRNA were significantly decreased (P＜0.05).Conclusions LIF can protect retinal photoreceptor cells from light damage,which may result from the activation of Jak3/STAT3 signaling pathway and inhibition of its downstream Bax/Bcl-2 apoptotic pathway.

Protective effects and mechanisms of LIF on cone photoreceptors from oxidant injury / 眼科新进展

Objective To investigate the role of leukemia inhibitory factor (LIF) in cell survival of cone photoreceptors and the underlying mechanism following oxidant injury.Methods 661W cells were cultured and randomly divided into normal control group,LIF intervention group,H2O2 intervention group,S3 I201 intervention group,H2O2 + LIF intervention group,H2O2 + S3I201 intervention group and H2O2 + LIF + S3I201 intervention group,according to the different intervention drugs.MTT assay and Western blot were used to detect the effects of LIF pretreatment on 661W activity and the expression of STAT3 protein and its phosphorylation level after oxidative damage.Using STAT3-specific inhibitor S3I201 to block the STAT3 signal transduction pathway,MTT assay and real-time PCR were used to detect the effects of STAT3 signaling pathway on 661 W activity and the mRNA expression of survivin bcl-2 and bcl-xi after oxidative damage.Results Compared to H2O2 intervention group,the relative protein expression of p-Tyr705-STAT3 was increased in H2O2 + LIF intervention group,the difference was statistically significant (P ＜ O.05);The relative protein expression of p-Tyr705-STAT3 was decreased in H2O2 + S3I201 intervention group,the difference was statistically significant (P ＜ 0.05).Compared to H2O2 intervention group,the cell activity of 661W cells was increased in H2O2 + LIF intervention group,the difference was statistically significant(P ＜0.05).Compared to H2O2 + LIF intervention group,the cell activity of 661W cells was decreased in H2O2 + LIF + S3I201 intervention group,the difference was statistically significant (P ＜ 0.05).Compared to normal control group,the mRNA expression of bcl-2 and bcl-xl were increased in LIF intervention group,H2O2 intervention group and H2O2 + LIF intervention group,the differences were statistically significant (all P ＜ 0.05).Compared to H2O2 + LIF intervention group,the mRNA expression of bcl-2 and bcl-xl were decreased in H2O2 + LIF + S3I201 intervention group,the differences were statistically significant (all P ＜ 0.05).Conclusion LIF has protective effect on oxidative injury of cone photoreceptors,and it may contribute to cell survival through activation of the STAT3 signaling transduction pathway and its related survivin.

Accuracy of three common optometry methods in examination of refraction in juveniles / 中南大学学报(医学版)

OBJECTIVE@#To compare the results of the three methods of Suresight handheld autorefractor, table-mounted autorefractor and retinoscopy in examination of juveniles patients with or without cycloplegia.
@*METHODS@#Firstly, 156 eyes of 78 juveniles (5 to 17 years old) were examined by using WelchAllyn Suresight handheld autorefractor and NIDEK ARK-510A table-mounted autorefractor with or without cycloplegia; secondly, retinoscopy was performed with cycloplegia.
@*RESULTS@#The spherical power measured by methods without cycloplegia were significantly greater than those measured with cycloplegia (P0.05). These results were highly consistent, suggesting a tendency towards a short sight. However, the spherical power and cylindrical power measured by table-mounted autorefractor was significantly different (P<0.05); with cycloplegia, there was significant difference in spherical power between Suresight handheld autorefractor and retinoscopy (P<0.05).
@*CONCLUSION@#Cycloplegic retinoscopy is necessary for juvenile refraction examination. Under natural pupil situation, Suresight handheld autorefractor is better than table-mounted autorefractor, though both show a myopia tendency. Nevertheless, table-mounted autorefractor can be taken as a recommendation for the prescription of lens trial. As a strong reference for subjective optometry, retinoscopy should be the gold standard for measuring refractive errors.

MK801 controls form-deprivation myopia by nitric oxide-cyclic GMP signaling pathway in guinea pig / 中南大学学报(医学版)

OBJECTIVE@#To investigate the mechanism of myopia following intravitreous injection of MK801 (dizocipine maleate) intravitreous injected.@*METHODS@#Three-week-old guinea pigs were divided into six groups: group A (control), group B (3 weeks form-deprivation in right eye), group C ( 3 weeks form-deprivation in right eye + saline), group D (3 weeks form-deprivation in right eye + MK801 1ng), group E (3 weeks form-deprivation in right eye + MK801 10 ng), group F (3 weeks form-deprivation in right eye + MK801 100 ng). The refraction and axial length of the eyes were measured. ncNOS was measured by hybridization in situ, and cyclic GMP (cGMP) concentrations by radioimmunochemistry. The correlation between MK801 concentration and diopter degree, axial length of the eyes, and levels of ncNOS or cyclic GMP were analyzed with linear correlation in the groups C-F.@*RESULTS@#Diopter degree was decreased, axial eye length was shorted and levels of ncNOS and c-GMP were decreased in groups C, D, E and F dependent on the concentration of MK801. The diopter degree had positive correlation with MK801 concentration (r=0.702, P<0.05), while the axial eye length and the levels of ncNOS and cGMP were negatively correlated (r=-0.736, -0.637, -0.725, P<0.05)@*CONCLUSION@#MK801 injected into the vitreous humor can restrain myopia by down-regulated the expression of the nitric oxide-cyclic GMP signaling pathway. The effect is concentration dependent.

Expression of cyclic guanine monophosphate and the ultrastructure change in retina of guinea pig with form-deprivation myopia / 中南大学学报(医学版)

OBJECTIVE@#To explore the expression of cyclic guanine monophosphate (cGMP) and the ultrastructure change in retina of guinea pig with form-deprivation myopia and the underlying mechanisms.@*METHODS@#Three-weeks-old guinea pigs were distributed in 3 groups: an untreated group (Group I), a myopia 2-weeks group (Group II) and a myopia 3-weeks group (Group III), animals underwent monocular form-deprivation by facemask for 2 and 3 weeks. The right eyes were deprived and the left eyes were self-controlled. The refraction and axial length of the eyes was measured. Retina was observed by electron microscope. The expression of cGMP was detected by radioimmunochemistry.@*RESULTS@#Deprived eyes in guinea pig showed significant development of myopia, the refraction and axial length was increased. The pathological changes in ultrastructure of retina were aggravated with the development of myopia. The expression of cGMP was significantly up-regulated in the deprived eyes compared with self-control eyes(P<0.05).@*CONCLUSION@#Form-deprivation can up-regulate the expression of cyclic GMP, which might play an important role in the development of myopia.

Expression and secretion of TGF-beta2 in human retinal pigment epithelium cell line D407 regulated by atropine / 中南大学学报(医学版)

OBJECTIVE@#To investigate the regulation of atropine to the expression and secretion of TGF-beta2 in retinal pigment epithelium (RPE) cells by observing the changes of those under different treatments of atropine and carbachol.@*METHODS@#D407 cells were cultured conventionally and divided into 4 groups as follows: (1) An experimental group (Group A), cells were pretreated with 10(-4)-10(-8) mol/L atropine for 30 min, and then treated with 10(-5) mol/L carbachol; (2) a negative control group (Group B), cells were treated with 10(-4)-10(-8) mol/L atropine; (3) a positive control group (Group C), cells were treated with 10(-5) mol/L carbachol; (4) a blank control group (Group D). The concentration of TGF-beta2 in the supernate, and the level of TGF-beta2 mRNA and protein were measured by ELISA, RT-PCR, and Western blot after the 24-hour treatment. The data were analyzed by analysis of variance.@*RESULTS@#The levels of TGF-beta2 mRNA and protein in the cytoplasm and the concentration of TGF-beta2 in the supernate in the experimental groups were lower than those of the positive control group. Atropine at 10-4 mol/L could completely inhibit the effect of carbachol at 10-5 mol/L. The effect of atropine was concentration-dependent (F=1,056.897,1,320.170, and 475.657; P0.05).@*CONCLUSION@#Carbachol can promote the expression and secretion of TGF-beta2 in human RPE cells and atropine could reverse it effectively, suggesting that M receptor may be involved.

Primary culture of rat retinal and visual cortical neurons:Methodological characteristics / 中国组织工程研究

BACKGROUND:Primary culture of neurons is an important way to study the structure and functions of the nervous system.It is also important to explore pathomechanism and medicine reaction of some ophthalmology diseases.OBJECTIVE:To explore an optimal way to the separation and culture of retinal and visual cortical neurons in new-bom rats through comparative observation of different primary culture methods.METHODS:Retinal and visual cortical neurons isolated from new-born rats were firstly cultured in Dulbecco's modified Eagle's medium supplemented with 10% new-born calf serum and 10% F12 nutrient mixtures,followed by maintaining culture in Neurobasal medium containing 2% B27 serum-free supplements.Nissls staining was performed for neuron identification.RESULTS AND CONCLUSION:Cultured neurons grew well with plump cell bodies and long processes.Nissls staining showed that the purity of retinal neurons was greater than 90% and the proportion of visual cortical neurons was higher than 50%.The results suggested that there are some differences in culturing methods and growth characteristics of retinal and visual cortical neurons of new-born rats,accordingly,different culture methods are required to obtain high purity neurons.

Clinical Observation on Orthokeratology Applied to Therapy Myopia / 中国医师杂志

Objective To evaluate the effectiveness of orthokeratology (Ortho-k) in treatment of myopia. Method Using Better Vision Contact lenses to treat 98 patients with myopia(192 eyes). The visual, the diopter of myopia and the corneal curvature were observed.Results Three monthes after treatment the myopia degree was reduced by-5 75D,astigmatism with rale was decreased by-2 75D,respectively,96 47% of low myopia (≤-3 00D),64 49% moderate-high myopia (-3 00D～-7 25D) were recovered to emmetropia. A positive correlation was found between the spherical equivalent and the corneal curvature (?=0 993,P