Abstract:To explore whether carnosine can protect α-crystallin modification and decrease chaperone by a steroid, and whether carnosine could directly react with a steroid. · METHODS: Bovine lens α-crystallin was separated by size- exclusion chromatography on a Sephacyl S-300 HR column. α-Crystallin was incubated with different concentrations of prednisolone-21-hemisuccinate (P-21-H) with or without carnosine for different times. The chaperone activity of α-crystallin was monitored using the prevention thermal aggregation of α-crystallin. The modified α-crystallin was examined by SDS-PAGE and fluorescence measurements. The absorbance spectra of solutions of carnosine and P-21-H were investigated. · RESULTS: P-21-H decreased the chaperone activity of α-crystallin in a concentration- and time-dependent fashion. Carnosine only worsened this effect. The tryptophan fluorescence intensity of α-crystallin modified by P-21-H was significantly decreased compared with unmodified crystallin, whereas its non-tryptophan fluorescence was increased with a shift to longer wavelengths in a time- and dose-dependent manner, suggesting that new fluorophores were possibly formed. Carnosine readily reacted with P-21-H thereby inhibiting steroid-mediated protein modification as revealed electrophoretically. The increased absorbance was time-dependent, suggesting adducts may be formed between carnosine and P-21-H. · CONCLUSION: Carnosine reacts with P-21-H, which suggests carnosine's potential as a possible anti-steroid agent.

Abstract:To observe the effects of chromosome 10 (PTEN) and the tumor suppressor gene in proliferative LECs of the rabbit. ·METHODS: Forty-two white rabbits were randomly divided into test group (36 rabbits) and control group (6 rabbits). The transparent lenses of treated rabbits were operated with extracapsular cortex extraction, and the controls were kept untouched. The rabbits were sacrificed 1 day, 3 days, 1 week, 2 weeks, 1 month and 2 months after surgery. Immunohistochemistry was applied to detect proliferative cellular nuclei antigen (PCNA) as well as hybridization and reverse-transcriptase polymerase chain reactions (RT-PCR) were applied to detect phosphatase as well as tensin homology deleted on PTEN mRNA in lens equartor. ·RESULTS: PCNA expression increased significantly to a high level at 1 week, began to reduce 2 weeks later, and recovered to the normal level 1 month or 2 months after the surgery. PTEN mRNA expressed positively in normal rabbit LECs. The relative PTEN mRNA contents reduced greatly 1 day after operation and remained low level at 3 day. It began to increase slightly at 1 week, kept rising at 2 weeks and regained the normal expression after 1 month or 2 months. There was inverse correlation between the PTEN mRNA and PCNA expression. ·CONCLUSION: PTEN mRNA expresses positively in normal rabbit LECs plasma. PTEN participates in LECs proliferation and correlates with lens proliferative conditions

Abstract:To observe the morphologic characters and the expression of vimentin on human lens epithelial cells (hLECs) cultured on laminin and fibronectin. METHODS: The primary and secondary hLECs were cultured on plates treated with laminin or fibronectin. The feature of hLECS was observed and recorded using an inverse microscope with digital camera and statistical analysis was applied. MTT assay was used to show the growth curve of subcultured cells (the 3^rd passage). Immunofluorescent staining was used to demonstrate the morphologic change in vimentin expression in the 3^rd passaged hLECs. RESULTS: The hLECs in laminin or fibronectin group grew out significantly earlier than the untreated group. The cells could be subcultured fluendly in those two treated groups, while only a few survival cells were found in the untreated group. But the hLECs could undergo apoptosis in laminin group at the terminal phase of their life cycle, while lentoid bodies emerged in fibronectin treated group. There were more viable cells in the fibronectin group from the 4^th to the 7^th day by MTT reaction. Immunofluorescent staining showed a clear morphological difference between the two groups. CONCLUSION: Laminin provide a suitable growth microenvironment for the hLECs while fibronectin promotes the cells proliferation and differentiation.

Abstract:To observe the expression of COX-2 in rat corneal neovascularization (CNV) and its relationship to CNV, and to explore the inhibition of Celecoxib, a COX-2 inhibitor, to CNV. · METHODS: The distribution and quantification of COX-2 and VEGF was detected by immunohistochemistry. Expression of COX-2 and VEGF mRNA was quantified by RT-PCR. The difference in protein and mRNA expressions of COX-2 and VEGF was analyzed to find the correlation between them. · RESULTS: Expression of activated COX-2 and VEGF protein and mRNA in CNV had a dynamic change. VEGF and COX-2 co-localized. Compared with the control group, expression of both protein, mRNA of COX-2 and VEGF in experimental group II and III had significant difference(P <0.05),indicating the correlation between COX-2 and VEGF, while that in experimental group I had no statistical difference (P >0.05). · CONCLUSION: COX-2 expression was up-regulated in inflammatory CNV. COX-2 modulates the expression of VEGF, playing a very important role in CNV. Celecoxib inhibit COX-2 expression so as to hold back the CNV.

Abstract:To explore the dynamic expression and correlation among telomerase catalytic subunit (TERT), proliferating cell nuclear antigen（PCNA）and antiapoptosis protein Bcl-2 which relate to cell proliferation in epiretinal membrane （ERM）of rat traumatic proliferative vitreoretinopathy (PVR). · METHODS: S-P technique was applied for immunohisto- chemical staining of ERM of traumatic PVR with TERT, PCNA and Bcl-2 antibody. HE staining was also carried out. The staining results were analyzed with image analysis system. · RESULTS: The positive rate and average A of PCNA protein were up regulated at first and then down regulated, with the peak value in 14 days Group, which was significantly different from those in 7 days Group and 28 days Group. The positive rate and average A of TERT and Bcl-2 were also up regulated at first and then down regulated, with the peak value in 14 days Group and 21 days Group, which were significantly different from those in 7 days Group. There was significant correlation among PCNA, Bcl-2 and TERT protein expression (P ≤0.01). · CONCLUSION: TERT and Bcl-2 take part in the regulation of proliferative cells in ERM of traumatic PVR, with high correlation with the dynamic changes of cell proliferation.

Abstract:To explore the role that hepatocyte growth factor (HGF) plays in proliferative vitreoretinopathy (PVR) after retinal detachment（RD）. · METHODS: The contents of HGF in subretinal fluid (SRF) in 49 cases with RD were measured with enzyme-linked immunosorbent assay. · RESULTS: With the worsening of PVR and vitreous opacity and prolonging of disease course, the contents of HGF increased ，P <0.05 was considered statistically significant. · CONCLUSION: The change of HGF in SRF had a close relationship with the occurrence and development of PVR after RD.

Abstract:To investigate the sequential changes of HIF-1α protein and mRNA in hypoxic bovine retinal microvessel endothelial cells. METHODS: The bovine retinal microvessel endothelial cells were cultured in normoxic and CoCl₂-induced hypoxic conditions respectively. Expressions of HIF-1α protein were measured with immunohistochemical staining, and RT-PCR was used to determine the HIF-1α mRNA. RESULTS: HIF-1α began to increase 1 hour after hypoxia, and reached the peak at 4 hour. After 16 hours, it declined significantly. Compared with the normoxic group, the expression of HIF-1α protein in the hypoxic groups had significant difference (P <0.01), and HIF-1α mRNA expression was unchanged under hypoxia. CONCLUSION: HIF-1α participates in the hypoxic procedures in retinal microvessel endothelial cells, and hypoxia induce time-dependent changes of HIF-1 α protein expression, which is not modulated on the transcription level. Analysis of HIF-1 α expression revealed a temporal and spatial changes with regard to the hyperoxic repression, indicating that HIF-1 may play a major role in the development of retinopathy of prematurity(ROP) and other ischemic retinal disorders such as diabetic retinopathy(DR).

Abstract:To investigate whether Erigeron Breviscapus (vant) Hand-Mazz (EBHM) has neuroprotective effect against N-methyl-D-aspartate (NMDA)-induced neuron death in retinal ganglion cell layer (RGCL). · METHODS: Sixty healthy SD rats were randomly divided into four groups. 6 animals were normal control group (group A). The others were divided as group B (EBHM group), group C (normal saline+NMDA group) and group D(EBHM + NMDA group), each group had 18 rats. 10nmol NMDA was intravitreally injected to induce partial damage of the neurons in RGCL in the right eyes of Groups C and D. Same volume PBS was intravitreally injected into the left eyes as self-control. Groups B and D were pretreated intraperitoneally with 6g/L EBHM solution at a dose of 150mg/kg body weight/day seven days before and after NMDA treatment. Group C were administrated intraperitoneally with 9g/L normal saline at the same time of EBHM injection. Rats were sacrificed at 4,7,14 day after NMDA treatment. Flat whole retinas were stained with 5g/L cresyl violet and neuron counting in RGCL from both eyes were observed. Each subgroup had 6 rats. · RESULTS: There was no significant difference of neuron counting in RGCL between the right eye and the left eye in group A. There was no significant difference between normal control group and EBHM group either in the right eyes or in the left eyes at 4, 7 and 14 day respectively after intravitreal injection of 10nmol NMDA in group C and group D. (P = 0.636, P =0.193). Neuron counting of RGCL in group C and D was significantly decreased in the NMDA- treated eyes 4, 7 and 14 days after intravitreal injection (P < 0.001). There was no significant difference between self-control eyes group and normal control group. However, neuron counting was significantly higher in the EBHM+NMDA group than normal saline +NMDA group 14 days after intravitreal injection (P = 0.044), but lower than normal control group (P <0.05). · CONCLUSION: EBHM has no effect on neuron counting of RGCL when administered alone in normal rats. The results indicate that EBHM plays a partial protective role in NMDA-induced neuron loss in RGCL in rats.

Abstract:To investigate the role of pericytes in growth of retinal microvascular endothelial cells(RMECs) in a co-culture system in order to understand some mechanism of angiogenesis in hypoxia induced retinal neovascular disorders. · METHODS: RMECs were isolated by a modified protocol using CD31 coated Dynabeads, and identified by immunocytochemical staining with anti-Factor VIII and CD31 antibodies. Rat retinal pericytes were isolated and characterized by immunofluorescent staining with PDGFR-β; and desmin antibodies. Pericytes and RMECs were cultured in a contact co-culture system both under normoxia and hypoxia by Millicell chamber. RMECs proliferation was evaluated by MTT and cell cycle assay with flow cytometry. RT-PCR was used to detect the alteration of KDR/Flk-1 mRNA level in RMECs under normoxia or hypoxia in the co-culture system. · RESULTS: Highly pured rat RMECs and pericytes were harvested with the modified isolating method. The two cell types were identified by positive Factor VIII, CD31 and PDGFR-β, desmin cytochemical staining respectively. RMECs proliferated significantly under hypoxia from 3 to 9 day with a maximal rate on day 6 (24.9%, P < 0.01) by MTT. In the co-culture system, the proliferation of RMECs was inhibited by pericytes. After 6 days exposure to hypoxia, the fraction of S-phase RMECs number was greatly increased by 43.9%(P < 0.01). In the co-culture system, RMECs proliferation was inhibited by pericytes through decreasing the fraction of S-phase cell number both under normoxia (3.6%, P <0.05) and under hypoxia (15.1%,P <0.01). KDR/Flk-1 mRNA level in single cultured RMECs was shown to increase approximately 1.3-fold when exposed to hypoxia. Compared with single cultured RMECs, co-culture with pericytes could decrease KDR/Flk-1 mRNA by 45.1% (P <0.05) and 27.7% (P <0.05) under normoxia and hypoxia condition respectively. · CONCLUSION: The present study demonstrated that pericytes could inhibit proliferation of RMECs under both normoxia and hypoxia. The inhibition effects of pericytes maybe, at least in part, due to downregulation of KDR/Flk-1 of RMECs. These findings confirm that pericytes could be a potential inhibitor in the pathogenesis of retinal neovascularization(RNV).

Abstract:To observe the inhibitory effect of triamcinolone acetonide (TA) on the proliferation of monkey choroid- retinal endothelial cells (RF/6A) in hypoxia or normal conditions. · METHODS: TA was added into the cultured RF/6A of rhesus monkey. The effect of TA on the cellular activity was observed by MTT, the effect on cellular proliferation and apoptosis was detected by flow cytometry (FCM). · RESULTS: The numbers of cells in s-phase of a cell cycle were reduced and the proportion of cells in G2-M phase was increased under the hypoxia condition. TA had a great effect on the cell cycle of RF/6A of rhesus monkey and it induced apoptosis of endothelial cells. It relatively increased the s-phase cells and reduced G2-M phase cells under both normal and hypoxia conditions, which indicates its role in blocking cell cycle from s-phase to G2-M phase and reducing mitosis. · CONCLUSION: Hypoxia promotes the proliferation of RF/6A cells while TA has the opposite effect in both normal and hypoxia conditions. TA can also induce apoptosis of endothelial cells.

Abstract:To study the experimental method of inducing the chronic intraocular hypertension in rat eyes. · METHODS: Twenty Wistar rats were randomly divided into ocular hypertension and sham control groups. Intraocular pressure (IOP) was raised by electrocoagulating at least 3 episcleral and limbal veins on the right eye of each rat in ocular hypertension group and its contralateral eye was used as control. At 1, 2, 3, 4 and 8 week after the electrocoagulation of the veins, IOP were measured. · RESULTS: The treatment of electrocoagulation caused a significant IOP increase of the right eyes over the baseline, over the contralateral eyes, and over the sham control eyes (repeated measures ANOVA, P <0.001). At 1 week, IOP was 30.12±5.18mmHg, and maintained the high IOP up to 8 weeks. · CONCLUSION: The chronic intraocular hypertension model could be successfully created by electrocoagulating three or more episcleral and limbal veins.

Abstract:To investigate the association between cycloxygenase-2　(COX-2) expression and vascular endothelial growth factor (VEGF) intervention as well as the inhibitory effect of Meloxicam on the cultured human pterygium fibroblasts (HPF). · METHODS: Expression of COX-2 was measured by immun- ohistochemistry in the cultured HPF from twenty excised pterygium cases. Expression of COX-2 in HPF was measured by Western blot following the treatment of VEGF at different concentrations. In addition, the effect of Meloxicam on proliferation of HPF was studied by adding different concentrations into the cultured HPF plates by Mono-nuclear cell direct cytotoxicity (MTT) reduction assay. · RESULTS: COX-2 expression was present in the cultured HPF. The level of the expression increased following VEGF treatment. The proliferation of the cultured HPF decreased following the addition of different concentrations of Meloxicam (from 75μmol/L to 300μmol/L) and the magnitude of the inhibition was dose-time dependent. · CONCLUSION: COX-2 levels in the cultured HPF were positively associated with VEGF stimulation and Meloxicam was inhibitory to HPF proliferation.

Abstract:To summarize the clinical features of Chinese primary congenital glaucoma(PCG) and to investigate the discrepancies of the clinical features between the Chinese and Indian patients. · METHODS: Clinical records of 40 Chinese PCG patients were reviewed. The clinical features were summarized as several quantifiable clinical parameters and the severity of the disease was evaluated. Both the quantified clinical features and severity were statistically compared with those of the Indian patients, which were cited from the previously published articles. · RESULTS: Forty Chinese and 43 Indian patients were included in the study. In Chinese patients, sex ratio (male to female )was about 2:1, family history was presented in 3 patients(7.5%) and consanguinity was found in one patient (2.5%). The main symptoms and signs observed in Chinese patients spanned a wide spectrum of manifestations. The most frequent signs noted in the initial examination were enlarged eyeball (42.5%) and decreased visual acuity(VA)(35.0%). Compared with Indian patients, Chinese patients had a later onset, a delayed diagnosis , more severe corneal changes and more severe optic nerve damages(P <0.01). The combined trabeculectomy and trabeculotomy operation was preferred by both Chinese and Indian doctors whereas a higher proportion of Indian patients received the combined operation (P <0.01). The proportions of the severity grade were different between Chinese and Indian patients. Most Chinese patients were in the severe grade while most Indian patients were in the very severe grade (P <0.01). · CONCLUSION: Chinese PCG patients were sporadic and non-consanguineous. Compared with Indian patients, Chinese patients had a relative later onset, a delayed diagnosis and treatment. More attempts are needed in Chinese PCG prevention and treatment.

Abstract:To determine the influence of topical anaesthetic drops, age and central corneal thickness (CCT) in the determination of intraocular pressure (IOP) by non contact tonometry (NCT). · METHODS: Ninety-three eyes from 47 patients were examined for CCT and IOP by NCT before and after the instillation of topical anaesthetic drops. · RESULTS: Average age was 66.4 (SD 16, range 34 to 88 years-of-age). Thirty one patients were female and 16 were male. Average basal IOP was 16.0mmHg (SD 4.0, range 8.5 to 26.1). IOP one minute after topical anesthesia instillation was 15.0mmHg (SD 3.8, range 7.7 to 26.7), and 14.9mmHg (SD 3.9, range 7.6 to 26.3) five minutes after the instillation. The differences were statistically significant for the 0 to 1 minute lapse(P =0.0007) and for the 0 to 5 minute lapse (P = 0.0003), but not for the 1 to 5 minute lapse (P =0.27) (Student's t test for paired data). Average CCT before topical anaesthetic drops was 565.4 microns. Simple linear regression analysis demonstrated absence of significant variation between age and IOP changes and between CCT and IOP changes. · CONCLUSION: Our study confirms that the instillation of topical anaesthetics causes a reduction in IOP, which is progressive during the first 5 minutes after instillation. This IOP reduction does not seem to be associated with basal CCT or age.

Abstract:To investigate the early changes of retinal function in diabetic patients detected by multifocal electroretinogram (mfERG). ·METHODS: The first-order kernel responses of mfERG were recorded fromeyes of 33 normal control subjects, 63 diabetic patients without retinopathy and 43 diabetic patients with background retinopathy. The response densities and implicit times of N₁ and P₁ were compared among the control, diabetic patients without retinopathy and diabetic patients with retinopathy. ·RESULTS: The response densities of N1 and P1 in central 3 rings were reduced significantly in diabetic eyes with and without retinopathy. And the implicit times of N₁ and P₁ were delayed significantly only in diabetic eyes with retinopathy. ·CONCLUSION: mfERG can detect the early changes of retinal function quantitatively in diabetic patients. Analysis of response densities and implicit times of N₁ and P₁ can reflect the progress of local retinal dysfunction in diabetes

Abstract:To investigate the early changes of retinal function in diabetic patients detected by multifocal electroretinogram (mfERG). ·METHODS: The first-order kernel responses of mfERG were recorded fromeyes of 33 normal control subjects, 63 diabetic patients without retinopathy and 43 diabetic patients with background retinopathy. The response densities and implicit times of N₁ and P₁ were compared among the control, diabetic patients without retinopathy and diabetic patients with retinopathy. ·RESULTS: The response densities of N1 and P1 in central 3 rings were reduced significantly in diabetic eyes with and without retinopathy. And the implicit times of N₁ and P₁ were delayed significantly only in diabetic eyes with retinopathy. ·CONCLUSION: mfERG can detect the early changes of retinal function quantitatively in diabetic patients. Analysis of response densities and implicit times of N₁ and P₁ can reflect the progress of local retinal dysfunction in diabetes

Abstract:To assess the effect of a single dose of Sildenafil citrate on the visual function in men with early-stage age related macular degeneration(AMD). · METHODS: Forty men (mean age 71, range from 55-86 years)with early-stage AMD were prospectively randomized to receive either placebo or Sildenafil citrate (Viagra; Pfizer Inc, New York, NY) 100mg as a single oral dose. Subjects underwent visual acuity, Amsler grid and color discrimination in each eye before and at specific intervals within 9 hours after dosing. · RESULTS: Compared with placebo, no pattern of errors were evident in any visual function test following Sildenafil administration. No statistically or clinically relevant changes from baseline were observed in visual acuity or color discrimination. No clinically relevant changes were observed in the Amsler grid. Sildenafil treatment was associated with transient mild or moderate headache and flushing. · CONCLUSION: A single 100mg dose of Sildenafil was well tolerated and produced no significant acute visual effects in a sample of men with early-stage AMD.

Abstract:To compare the visual effects of optimized aspheric transition zone Laser keratomileusis （OATｚ-LASIK ） versus conventional Laser in situ keratomileusis (con. LASIK). METHODS: In a prospective study 44 patients (88 eyes) underwent OAT_ｚ-LASIK and 50 patients (92 eyes) received conventional LASIK surgery. Visual acuity,refractions、contrast sensitivity （CS）, glare sensitivity （GS）, and increment of Q-value after surgery were studied. RESULTS: All of operations on 94 cases were successful without severe complication after 3 months' follow-up. There was no significant difference in term of postoperative refractions between the two groups ( -test). The uncorrected visual acuity (UCVA), CS, GS, and increment of Q-value of OAT_ｚgroup were significantly better compared to the tradition group 3 months after the surgery ( <0.05). CONCLUSION: OATｚ- LASIK is a more effective procedure to improve visual quality compared to conventional LASIK

Abstract:To assess the prevalence and risk factors for age related macular degeneration (AMD) in a rural population in Shaanxi Province of China. · METHODS: A total of 2 835 (81.00%) people aged 40 years old or more, from Fuping county, Jingbian county and Yang county of Shaanxi Province, China, underwent a comprehensive interview and a relative eye examination. The present of AMD was classified into neovascular AMD (NV) and pure geographic atrophy (GA) by using direct ophthalmoscopy for fundus examination according to International Classification System. · RESULTS: The prevalence (95%CI) of AMD was 3.00% (2.42, 3.71) in this population, of which NV accounted for 1.45% (1.05, 1.98) and 1.55% (1.14, 2.10) for GA. The prevalence of AMD increased significantly with increasing age (P <0.01). AMD was present in 0.47% of participants aged 40 to 49 years, rising to 11.90% of participants older than 80 years, of which the corresponding data increased from 0.28% to 4.76% for NV and from 0.19% to 7.14% for GA. No significant difference was found in the prevalence of NA and GA between genders in this population. With multiple logistic analysis, apart from advancing age, only smoking was found to have a strong association with any type of AMD. · CONCLUSION: The prevalence of AMD in the rural population of Shaanxi Province of China is lower than that reported from other population-based studies in different provinces of China, less than that reported in whites, more than that reported in blacks. Besides increasing age, smoking is also a significant well-known risk factor for AMD.

Abstract:The mechanisms of regeneration and protection of optic nerve, the represent of central nerves, are researched more and more profoundly and extensively in recent years. The retinal ganglion cells(RGCs) protection after injury is stopping or preventing it from apoptosis mainly. The methods include glutamic acid inhibitor, nitric oxide (NO) inhibitor, neurotrophic factor, gene therapy, acupuncture, traditional Chinese medicine and so on. However, there are no medicines or operations that play definite curative role in the RGCs protection after injury up to now. So the ganglion cells protection is at its exploratory research stage, which will shoulder heavy responsibilities