Objective To investigate the possible effects of phosphorylated signal transduction and activator of transcription3 (STAT3) in the formation of choroidal neovascuarization (CNV) induced by photocoagulation in rats. Methods The CNV model in rats induced by photocoagulation was established, and the expression of phosphorylated STAT3 at the early stage in CNV were observed by immunofluorescence. To set up the hypoxia model, the specific inhibitor of Janus kinase 2 (JAK2), AG490 was mixed into cell culture fluid and then cultured for 0,1 hour,3,6,12,and 24 hours.Retinal pigment epithelial (RPE) cells proliferation activity were detected by flow cytometry (FCM).the expression of hypoxiainducible factor (HIF)1α and vascular endothelial grow factor (VEGF) mRNA were detected by reverse transcriptase polymerase chain reaction (RT-PCR); the expression of HIF1α protein was detected by Western blot; the content of VEGF in the supernatant of cell culture fluid was measured by enzyme linked immunosorbent assay (ELISA). Results Phosphorylated STAT3 highly expressed in CNV areas in rats 3 days after the photocoagulation. The proliferation activity of human RPE cells under hypoxia condition significantly decreased after inhibition of JAK2/STAT3 signal transduction pathway (t=1.472, 3.566,2.391,6.420; P=0.054,0.038,0.042,0.016). The expression of HIF-1α and VEGF mRNA increased gradually with increasing time of hypoxia;while the expression of HIF1α and VEGF mRNA and the activation of HIF1α protein in cultured human RPE cells with the JAK/STAT3 signal transduction pathway blocked by AG490 were suppressed obviously under hypoxia condition (t=0.07,0.02,0.01, P<0.05); the content of VEGF in RPE cells supernatant decreased significantly (t=1.330,1.106,2.828,7.742,5.610,6.894; P=0.082,0.063,0.014,0.002,0.016,0.011). Conclusion STAT3 may be involved in CNV formation, which may partly dependent on JAK2/STAT3 signal transduction pathway regulating the expression of HIF-1α and VEGF in RPE cells.
Objective To investigate the role of intracellular Ca2+ and MERTK in the phagocytosis of human retinal pigment epithelial (RPE) cells, and reveal the relationship between MERTK and intracellular Ca2+. Methods The cultured RPE cells were incubated with rod outer segments (ROS) at 37℃, the phagocytosis was terminated at different incubation time points. The concentration of intracellular Ca2+ was assayed by Fluro-3/AM loading methods combined with fluorescence microscope and CCD system, and the mRNA level of MERTK gene was measured by reverse transcription polymerase chain reaction (RT-PCR). Treating the RPE cells with stimulator (A23187) or inhibitor (verapamile) of intracellular Ca2+ to observe the changes of MERTK gene expression. Results ROS adhered to hRPE cells at the 15th minute, and the ingestion saturated at the 24th hour. The concentration of intracellular Ca2+ increased at the 15th minute, and kept the high level in 24 hours. The level of MERTK mRNA increased at the 5th minute, and kept the high level duration the whole incubation. When RPE cells were treated by A23187, the expression of MERTK increased in a dose-dependent manner. After RPE cells was pretreated by A23187, the expression level of MERTK was higher in the proceeding incubation groups than which in the control group except at the 3rd hour. When RPE cells were treated by verapamil, the expression level of MERTK decreased in a dosedependent manner. After RPE cells were pretreated by verapamil , the expression level of MERTK was lower in all the proceeding incubation groups than which in the control group (Plt;0.05). Conclusion MERTK gene and Ca2+ play an important role in sustaining RPE cells phagocytizing ROS. As an up-stream regulator, the receptor tyrosine kinase MERTK keeps RPE cells phagocytizing ROS by starting the intracellular Ca2+.
Objective To investigate the distribution of the preferred retinal locus (PRL) of eccentric fixation in eyes with high myopia.Methods A total of 40 highly myopic patients (54 eyes ) with eccentric fixation were examined by MP1 microperimeter to identify the PRL. The position of PRL relative to the fovea was estimated using the 90% confidence ellipse of normal adult foveal fixation. The differences of visual acuity between ldquo;desirablerdquo; and ldquo;undesirablerdquo; PRL were tested by analysis of variance.Results In 54 eyes with high myopia, 24 eyes (44.44%) had PRL of eccentric fixation below the scotoma after loss of central vision; 19 eyes ( 35.19% ) had a leftfield PRL; 6 eyes ( 11.11% ) had an upperfield PRL; and 5 eyes ( 9.26% ) had rightfield PRL. In 14 patients who had binocular eccentric fixation, 13 had the same fixation pattern in both eyes, including lowerfield PRL in 7 （50.00%）, leftfield PRL in 5 （35.71%）, and upperfield PRL in 1 patient （7.14%）. The difference of visual acuity between lower and leftfield PRL group and right and upperfield undesirable PRL group was not statistically significant（F=0.144, Pgt;0.05）. Conclusions The eccentric fixation in eyes with high myopia is usually situated as near as possible to the fovea. The optimal PRL is inferior visual field.
Purpose To evaluate differences in the pattern of optic disc and retinal nerve fiber layer (RNFL) damage in normal-tension glaucoma (NTG) and high-tension glaucoma (HTG) patients. Methods We enrolled 49 eyes of 49 patients:30 NTG (IOP≤21 mm Hg,1 mm Hg=0.133 kPa), 19 HTG(IOP≥25 mm Hg). Mean age was 59.2±12.3 (range, 36-75) for HTG patients, and 59.6±8.6(range, 39-71) for NTG patients. All patients underwent complete ophthalmic examination, achromatic automated perimetry (AAP), scanning laser ophthalmoscopy (SLO), scanning laser polarimetry (SLP), optical coherence tomography (OCT) and Heidelberg retinal tomography (HRT). All patients had glaucomatous optic nerve damage and abnormal AAP. Results There were no differences in mean deviation on AAP between NTG and HTG eyes (P=0.37), while the corrected pattern standard deviation was larger in NTG than in HTG eyes (P=0.014). Cup∶disc area ratios in global (P=0.03) and three sectors (Plt;0.05) except nasal sector were significantly larger in the NTG group, whereas rim area in global (P=0.03) and three sectors (Plt;0.05) except nasal quadrant obtained by SLO were smaller in NTG than in HTG eyes. The other numerical parameters obtained by three imaging technologies could not detect differences in the optic disc or RNFL anatomy between the two groups. Conclusions Cup∶disc area ratio was larger in patients with NTG than in those with HTG, whereas significant thinning of rim was associated with NTG eyes. The measurement of retinal nerve layer thickness in global and each quadrant was similar between two groups. More focal or segmental analysis of the data contained within SLO, SLP and OCT images are needed to detect localized differences in eyes with varying levels of IOP. (Chin J Ocul Fundus Dis, 2002, 18: 109-112)
Objective To evaluate glaucoma and anterior chamber angle changes after intravitreal silicone oil injection(SOI). Methods The intraocular pressure(IOP) and anterior chamber angles of 34 e yes(33 patients)undergone pars plana vitrectomy and SOI were observed. Results Glaucoma occurred in 9 eyes(26%),in which silicone oil glaucoma(SOG) accounted for 77%(7/9).The changes of the superior part of anterior chamber angle were peripheral anterior synechiae in 11 eye(32%) and SO emulsification droplets in 22 eyes(64%) in 1～4.5 months after surgeries.Glaucoma occurred in 6 eyes of 7 eyes undergone peripheral iridectomy at the inferio r part of the iris after the closure of iridectomy holes (plt;0.05). Conclusion High incidence of glaucoma was found in this series of patients after intravitreal silicone oil injection,and the main causes of SOG were closure of the inferior iridecomy hole and silicone emulsification. (Chin J Ocul Fundus Dis, 2001,17:105-107)
Objective To investigate the regulative characterisitics of growth factors on proliferation of retinal pigment epithelial (RPE) cells in vitro. Methods Primary culture and subculture of RPE cells were establised in vitro Tumor.necrosis factor-alpha;(TNF-alpha;),interleukin-1beta;(IL-1beta;) and basic fibroblast growth factor (bFGF) in different concentrations were added to the RPE cells.3 H-thymidine(3 H-TdR) incorporation and a hemocytometer measured DNA synthesis and cell number separately. Results After RPE cells were separately treated with TNF-alpha;,IL-1beta; and bFGF,DNA synthesis was increased by 2.74,2.66 and 1.69 folds and cell number was increased by 54%,22% and 7amp; (Plt;0.05) respectively. When two growth factors were combined (TNF-alpha;+bFGF, IL-1beta;+bFGF),3.14,2.84 and 2.57 folds increased DNA synthesis significantly in each group (Plt;0.05). Compared with value by effect of two growth factors,the combination effect of three growth factors (TNF-alpha;+IL-1beta;+bFGF) was still ber (Plt;0.05). Conclusion The synergism of growth factors in their action might be one of the important roles in modulating the proliferation of RPE cells. (Chin J Ocul Fundus Dis,1998,14:95-97)
Purpose To investigate the clinical features and pathogenesis of acute posterior multifocal placoid pigment epitheliopathy(APMPPE). Methods To observe the features in 8 eyes of 6 cases of APMPPE with fundus fluorescein angiography(FFA) and indocyanine green angiography(ICGA).One of the cases had been observed continuously for 160 days. Results 1.FFA: at the acute stage of APMPPE,the affected foci showed low fluorescence in the early phase and stained gradually in 3 eyes;the fluorescence of recessive foci were still lower in 4 eyes,and the stale one showed window defect fluorescence due to some RPE fading and fluorescence sheltering due to pigment deposit.2.ICGA:at acuted stage,the fluorescence of choroid lobules was ofen defected untill in late period of pathogenical changes. Conclusion The findings demonstrate the obstruction of choriocapillaries may be the primary pathogenesis of APMPPE. (Chin J Ocul Fundus Dis,1998,14:84-87)
ObjectiveTo compare the choroidal thickness (CT) of macular and peripapillary area among malignant glaucoma(MG), chronic primary angle-closure glaucoma (CPACG) and normal control eyes. And to investigate the correlation between CT and MG. Methods Sixteen subjects (32 eyes) with MG, 31 (31 eyes) with CPACG and 32 (32 eyes) normal controls were collected. MG eyes and the fellow non-MG eyes were included in the MG group. CT of all subjects was measured in the fovea, 1mm and 3mm to the fovea and peripapillary area using enhanced-depth imaging technique of optical coherence tomography (OCT-EDI). The average of CT in fovea by horizontal and vertical macular scan was defined as the average CT in fovea. The average of temporal, superior, nasal and inferior CT in 1 mm and 3 mm to the fovea were measured respectively. The average of temporal, superior, nasal and inferior CT was defined as the average CT in peripapillary area. The differences of CT among MG, CPACG and normal controls were compared. And the differences of CT between MG eyes and the fellow non-MG eyes were compared. ResultsAfter eliminating the influence of age, the average CT of MG in the fovea, 1mm and 3mm to the fovea was significantly thicker than that of CPACG and normal controls (P < 0.05). And the average CT of CPACG in the fovea, 1mm and 3mm to the fovea was significantly thicker than that of normal controls (P < 0.05). In peripapillary area, the temporal, superior and inferior CT of MG was significantly thicker than that of CPACG and normal controls (P < 0.05). There was no significant difference of CT in peripapillary area between CPACG and normal controls (P > 0.05). In the fovea, 1mm and 3mm to the fovea and peripapillary area, there was no significant difference of CT between MG eye and the fellow non-MG eye in MG group (t=－1.029~－0.130, P > 0.05). ConclusionsThe choroid thickness of macular and peripapillary area in MG eyes is thicker than that of CPACG and the normal controls. An increased CT of macular and peripapillary area may be one of the risk factors for MG.