A novel three-dimensional electric ophthalmotrope for improving the teaching of ocular movements.

AIM: To develop a novel three-dimensional (3D) electric ophthalmotrope to improve the ophthalmology teaching effectiveness and evaluate the teaching value. METHODS: A 3D electric ophthalmotrope was designed by simulating the movement of the ocular and the extraocular muscles according to Sherrington's law. The model with joint bearing was to ensure the flexibility and centripetal rotation of the simulated ball and stepper motor as the driving device. A programmable processor was used to control the motion amplitude of the stepper motor. The size of hole was set at the back of the simulated shell to limit the amount of eye movement. Afterwards, using a 5-point Likert scale, 7 experts evaluated the 3D electric ophthalmotrope's simulation ability and precision, compared with the traditional anatomical model. In addition, the teaching effectiveness of the 3D electric ophthalmotrope was evaluated at in-class quiz and final exam in a randomized controlled trial. RESULTS: The 3D electric ophthalmotrope could be operated easily to demonstrate the eye movements with motion of different ocular muscles. The experts agreed that the 3D electric ophthalmotrope was different from the traditional model and was easier for students to understand every extraocular muscles' movement in each evaluation index (P<0.05). Moreover, the results of teaching effectiveness showed that the 3D electric ophthalmotrope were significantly greater than the traditional model both at in-class quiz (P<0.01) and final exam (P<0.05). CONCLUSION: This novel 3D electric ophthalmotrope is better than the traditional model, which can be to improve the ophthalmology teaching effectiveness for students to understand the extraocular muscles' movement.

Anti-proliferative effect of olmesartan on Tenon's capsule fibroblasts.

AIM: To evaluate the inhibitive effect of olmesartan to fibroblast proliferation and the anti-scarring effect in Tenon's capsule, both in vitro and in vivo. METHODS: Human primary Tenon's capsule fibroblasts were cultured in vitro, treated with up titrating concentrations of olmesartan. The rate of inhibition was tested with methyl thiazol tetrazolium (MTT) method. Real-time PCR was performed to analyze changes in mRNA expressions of the fibrosis-related factors: matrix metalloproteinase-2 (MMP-2), tissue inhibitor of metalloproteinase (TIMP-1,2) and proliferating cell nuclear antigen (PCNA). Thirty rabbits were divided into 5 groups (3, 7, 14, 21, and 28d). A rabbit conjunctiva flap model was created in each eye. Olmesartan solution was injected subconjunctivally and then evaluated its anti-proliferation and anti-fibrosis effects through the histological morphology and immunohistochemistry of MMP-2 and PCNA in each group. Only the 7d group was treated with Masson's trichrome to compare the neovascularization in the subconjunctiva area. RESULTS: In vitro, cultured Tenon's capsule human fibroblasts showed a dose dependent inhibition by olmesartan in MTT. Olmesartan reduced mRNA expressions of MMP-2 and PCNA but increased mRNA expressions of TIMP-1 and TIMP-2. In vivo, the rabbit eyes treated with olmesartan at 3(rd), 7(th), 14(th) and 21(st) days demonstrated a significant reduced expressions of MMP-2 and PCNA compared with control eye, no significant difference observed in 28(th) day group. The cellular proliferation and neovascularization was suppressed by olmesartan in Masson's trichrome observation. CONCLUSION: By inhibiting fibroblasts in vitro and in vivo, olmesartan prevents the proliferation and activity of fibroblasts in scar tissue formation, which might benefit glaucoma filtering surgery.

Effects of lentiviral RNA interference-mediated downregulation of integrin-linked kinase on biological behaviors of human lens epithelial cells.

AIM: To investigate the effects of lentivirus (LV) mediated integrin-linked kinase (ILK) RNA interference (RNAi) on biological behaviors of human lens epithelial cells (LECs). METHODS: Human cataract LECs and immortalized human LEC line, human lens epithelial (HLE) B-3 cells were transfected by lentiviral vector expressing ILK-specific short hairpin RNA (shRNA) and then stimulated by transforming growth factor-ß (TGF-ß), the silencing of ILK gene and protein was identified by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot methods; biological behaviors including cell cycle and apoptosis, cell morphology, α-smooth muscle actin (SMA) stress fiber formation and cell migration were examined. RESULTS: Remarkable decreases of ILK protein expression were detected in LECs carrying lentiviral ILK-shRNA vector; flow cytometry revealed arresting of cell cycle progression through the G1/S transition and higher apoptosis rate in ILK-RNAi-LV transfected cells. Less α-SMA stress fiber formation and migration was observed in ILK-RNAi-LV transfected LECs. CONCLUSION: The present study demonstrated that ILK was an important regulator for LECs proliferation and migration. LV mediated ILK RNAi is an effective way to decrease ILK-regulated cell growth by arresting cell cycle progression and increasing cell apoptosis, as well as, to prevent cell migration by inhibiting TGF-ß induced α-SMA stress fiber formation. Thus, LV mediated ILK RNAi might be useful to prevent posterior capsular opacification.

LMWH inhibits anterior chamber inflammation after extra capsular lens extraction through down regulation of bFGF content in aqueous humor.

AIM: To observe the changes of basic fibroblast growth factor (bFGF) content in anterior chamber before and after extra capsular lens extraction for investigating the mechanism of low molecular weight heparin (LMWH) inhibiting anterior chamber inflammation. METHODS: Eighty-four rabbits were randomly divided into control and experimental group, 42 rabbits in each group. Extra capsular lens extraction was done on unilateral eye in each rabbit. LMWH was perfused into anterior chamber by the concentration of 50U/mL at the end of operation in experimental group. The degrees of corneal edema, aqueous flare and fibrin were evaluated with slit lamp microscope on postoperative day 1, 3, 6, 15, 30, 45 and 60, respectively. Six eyes of each group were at each time point. Contents of bFGF in aqueous humor were determined by ELISA after animals were killed. Another six eyes were used for determining the base line level of bFGF in aqueous humor. RESULTS: The degrees of corneal edema, aqueous flare and fibrin in experimental group were significantly lighter than those in control group (P<0.01) on postoperative day 1, 3 and 6, respectively. No difference was showed between the two groups at other point time. Contents of bFGF in aqueous humor increased at the same time. bFGF content reached peak on postoperative day 1 in experimental group, while on postoperative day 6 in control group. Contents of bFGF in the two groups declined slowly after reaching peak. The bFGF content in control group were significantly higher than that in experimental group 1-30 days after surgery (P<0.05). No significant differences were shown between the two groups on postoperative day 45 and 60, respectively. CONCLUSION: Perfusion with LMWH by the concentration of 50U/mL can significantly reduce anterior chamber inflammation after extra capsular lens extraction in rabbits, which may be related to down regulation of bFGF content in aqueous humor.

Filtering bleb area and intraocular pressure following subconjunctival injection of CTGF antibody after glaucoma filtration surgery in rabbits.

AIM: To study the role of connective tissue growth factor (CTGF) antibody in inhibiting bleb scarring after glaucoma filtration surgery (GFS) in rabbit model. METHODS: GFS was performed on both eyes in five rabbits. One eye of each rabbit was chosen randomly as antibody group and received subconjunctival injection of 0.1mL CTGF antibody (50mg/L) immediately after GFS applied and on the 5 th day after GFS. The other eye of each rabbit as control group was received subconjunctival injection of 0.1mL PBS at the same time as antibody group. On postoperative days 1, 3, 5, 7, 10, and 14, the appearance of filtrating blebs was observed under slit lamp, the area and the intraocular pressure (IOP) were measured with micrometer and applanation tonometer, respectively. RESULTS: On postoperative days 1, 3, 5, 7, 10, and 14, areas of filtrating blebs in antibody group were all larger comparing with the control group (P<0.05) and IOPs of antibody group were lower than the control group (P<0.05). CONCLUSION: Subconjunctival injection of CTGF antibody can maintain larger bleb area and lower IOP after GFS in rabbit.

[Effects of rAAV-mediated rhBDNF gene transfection on BDNF gene expression in the retina of a rabbit model of acute high intraocular pressure].

OBJECTIVE: To observe the changes in the expression of brain derived neurotrophic factor (BDNF) gene in the retina of rabbits with acute high intraocular pressure (IOP) after injection of recombinant adeno-associated virus (rAAV) vector containing human BDNF gene (rAAV-hBDNF), and investigate the neuroprotective mechanism of rAAV-hBDNF. METHODS: The unilateral eyes of 24 white rabbits were randomly chosen as the model group with high IOP induced by saline perfusion into the anterior chamber, and the contralateral eyes served as the control group without treatment. In another 24 white rabbits, 10 microl rAAV-BDNF was injected into the vitreous body of one of the eyes 3 days before induction of high IOP. On days 1, 3, 7, and 14 after perfusion, the bilateral eyes of 6 rabbits were excised for immunohistochemistry for the expression of endogenous BDNF gene in the retina. RESULTS: The number of BDNF-positive cells in the retina decreased after induction of high IOP, and injection of rAAV-hBDNF resulted in a significant increase in BDNF-positive cells as compared with the positive cell number in the high IOP model and control groups (P<0.05, P<0.01). CONCLUSION: rAAV-mediated BDNF gene transfection can increase endogenous BDNF expression in the retina of rabbits with acute high IOP. Intravitreous injection is an effective pathway for rAAV-hBDNF gene transfection into the retina.

[Neuroprotective effect of rAAV-mediated rhBDNF gene transfection on rabbit retina against acute high intraocular pressure].

OBJECTIVE: To investigate the neuroprotective effect of human brain-derived neurotrophic factor gene transfection into rabbit retina against acute high intraocular pressure (HIOP). METHODS: Acute HIPO was induced in one eye of 24 white rabbits via saline perfusion into the anterior chamber (model group), and the contralateral eye without treatment served as the control group. In another 24 rabbits, 10 microl recombinant adeno-associated virus (rAAV) vector containing human BDNF gene (rAAV-BDNF) was injected into the vitreous body of one of the eyes 3 days before the operation for HIPO (BDNF group). At 1, 3, 7, and 14 days after HIOP model establishment, 6 eyes in each group were excised to observe the number of retinal ganglion cells (RGCs) and the thickness of the inner retina layer. For the eyes dissected on day 14, electroretinogram b (ERG-b) wave was detected 30 min before (baseline) and on days 1, 3, 7 and 14 after HIOP. Another 5 rabbits were used for ultrastructural observation of the RGCs using transmission electron microscopy, including 1 without treatment, 2 with unilateral HIOP and 2 with rAAV-BDNF transfection before HIOP. RESULTS: The amplitude of ERG-b wave showed no significant difference between the 3 groups before HIOP (P>0.05). In HIOP model group and BDNF group, the amplitude decreased to the lowest at 1 day after HIOP and failed to recover the baseline level at 14 days (P<0.01); at the end of the observation, the amplitude was significantly higher in BDNF group than in the model group (P<0.01). Decreased number of RGCs and thickness of inner retina layer occurred in the model group, but these changes were milder in BDNF group (P<0.05, P<0.01). Electron microscopy revealed ultrastructural changes in the RGCs following acute HIOP, and transfection with rAAV-BDNF ameliorated these changes. CONCLUSION: rAAV-BDNF transfection protects the retinal structure and improves the amplitude of ERG-b wave after acute high IOP suggesting its neuroprotective effects.