Cross-talk between microRNA-let7c and transforming growth factor-ß2 during epithelial-to-mesenchymal transition of retinal pigment epithelial cells.

AIM: To explore the roles of microRNA-let7c (miR-let7c) and transforming growth factor-ß2 (TGF-ß2) and cellular signaling during epithelial-to-mesenchymal transition (EMT) of retinal pigment epithelial cells. METHODS: Retinal pigment epithelial (ARPE-19) cells were cultured with no serum for 12h, and then with recombinant human TGF-ß2 for different lengths of time. ARPE-19 cells were transfected with 1×106 TU/mL miR-let7c mimcs (miR-let7cM), miR-let7c mimcs negative control (miR-let7cMNC) and miR-let7c inhibitor (miR-let7cI) using the transfection reagent. The expression of keratin-18, vimentin, N-cadherin, IKB alpha, p65 were detected by Western blot, quantitative polymerase chain reaction and immunofluorescence. RESULTS: The expression of miR-let7c was dramatically reduced and the nuclear factor-kappa B (NF-κB) signaling pathway was activated after induction by TGF-ß2 (P<0.05). In turn, overexpressed miR-let7c significantly inhibited TGF-ß2-induced EMT (P<0.05). However, miR-let7c was unable to inhibit TGF-ß2-induced EMT when the NF-κB signaling pathway was inhibited by BAY11-7082 (P<0.01). CONCLUSION: The miR-let7c regulates TGF-ß2-induced EMT through the NF-κB signaling pathway in ARPE-19 cells.

Objective optical assessment of tear-film quality dynamics in patients with meibomian gland dysfunction and aqueous-deficient dry eye optical quality changes in different dry eye subtypes.

Purpose: To evaluate the optical quality and tear-film dynamics in patients with aqueous-deficient or evaporative subtype of dry eye disease (DED). Methods: Twenty-five aqueous-deficient dry eye (ADDE) patients, 25 DED patients with meibomian gland dysfunction (MGD), and 25 healthy subjects were included in this study. Vision-related health-targeted quality of life was evaluated using the Ocular Surface Disease Index (OSDI) questionnaire. Dynamic recording with a double-pass system (Optical Quality Analysis System [OQAS]) was performed in right eyes. Scattered light was measured as the objective scatter index (OSI) at 0.5-second intervals over 20 seconds without blinking. Then, we recorded OSI every 0.5 seconds within a 20-second period with the subjects asked to blink freely. Several parameters were established to evaluate the dynamic alterations of optical quality and the effects of blinks: OSI, OSI standard deviation (SD), ΔOSI, ΔOSI/time, blinking change (BC), and blinking frequency (BF). Additional clinical examination included tear film break-up time (BUT), Schirmer I test (SIT), fluorescein staining grade (FL), meibomian gland quality, meibomian gland expressibility, and meibomian gland drop-out. Results: The OSI, SD, ΔOSI, ΔOSI/time, BC, and BF were significantly higher in DED patients than controls (P < 0.01, respectively). The OSI, SD, ΔOSI, ΔOSI/time, BC, and BF were significantly higher in patients with MGD than patients with ADDE (P < 0.01). In the MGD group, BUT, FL staining score, lid abnormality, meibomian gland expressibility, and meibomian gland drop-out were correlated with Δ OSI and Δ OSI/time. Conclusion: Dry eye patients with MGD had significant alterations of optical quality compared with ADDE patients. The double-pass system has potential to be a useful quantitative method to evaluate the optical quality and tear-film dynamics in patients with dry eye.

Comparison of femtosecond laser-assisted descemetic and predescemetic lamellar keratoplasty for keratoconus.

PURPOSE: The purpose of this study is to compare the outcomes following femtosecond laser-assisted deep anterior lamellar keratoplasty (DALK) with 75% of stromal dissection (predescemetic group) and femtosecond laser-assisted DALK using big-bubble technique with total stromal resection (descemetic group) for the treatment of keratoconus. SUBJECTS AND METHODS: Twenty eyes of 17 patients with keratoconus were studied. There were 10 eyes of 9 patients in predescemetic group and 10 eyes of 8 patients in descemetic group. The postoperative best-corrected visual acuity (BCVA), manifest refraction, keratometry, endothelial cell density (ECD), and central corneal thickness (CCT) were analyzed. RESULTS: All surgeries were performed uneventfully. At 1 year after surgery, the BCVA, corneal astigmatism, keratometry, CCT, and ECD between two groups were not statistically significant (all P > 0.05). However, the mean manifest refraction was -9.43 ± 7.44 diopter (D) and -1.03 ± 1.13D in predescemetic and descemetic groups, respectively, which was statistically significant between two groups (P < 0.05). CONCLUSIONS: The results of BCVA and corneal astigmatism, keratometry, ECD, and CCT were comparable between two groups. However, the mean postoperative manifest refraction was lower in descemetic group.

Femtosecond laser-assisted deep anterior lamellar keratoplasty for keratoconus and keratectasia.

AIM: To describe the initial outcomes and safety of femtosecond laser-assisted deep anterior lamellar keratoplasty (DALK) for keratoconus and post-LASIK keratectasia. METHODS: In this non-comparative case series, 10 eyes of 9 patients underwent DALK procedures with a femtosecond laser (Carl Zeiss Meditec AG, Jena, Germany). Of the 9 patients, 7 had keratoconus and 2 had post-LASIK keratectasia. A 500 kHz VisuMax femtosecond laser was used to perform corneal cuts on both donor and recipient corneas. The outcome measures were the uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), corneal thickness, astigmatism, endothelial density count (EDC), and corneal power. RESULTS: All eyes were successfully treated. Early postoperative evaluation showed a clear graft in all cases. Intraoperative complications included one case of a small Descemet's membrane perforation. Postoperatively, there was one case of stromal rejection, one of loosened sutures, and one of wound dehiscence. A normal corneal pattern topography and transparency were restored, UCVA and BCVA improved significantly, and astigmatism improved slightly. There was no statistically significant decrease in EDC. CONCLUSION: Our early results indicate that femtosecond laser-assisted deep anterior lamellar keratoplasty could improve UCVA and BCVA in patients with anterior corneal pathology. This approach shows promise as a safe and effective surgical choice in the treatment of keratoconus and post-LASIK keratectasia.

Allogeneic corneoscleral limbus tissue transplantation for treatment of the necrosis in porphyria eye disease.

Porphyria cutanea tarda (PCT) with ocular complications are rarely reported. To the best of our knowledge, no reports exist on allogeneic corneoscleral limbus tissue transplantation for treatment of these. Amniotic membrane grafting had been performed in their patient suffering from porphyria eye disease, but necrosis developed in the grafts. Nevertheless, in our patient, allogeneic corneoscleral limbus transplantation prevented necrosis from development at corneoscleral limbus. So we considered that the allogeneic corneoscleral limbus transplantation might be an option to repair the necrosis in porphyria eye disease with avoiding sunlight and using artificial tear drops.

Application of tear meniscus measurement by anterior segment optical coherence tomography in the diagnosis of dry eye.

Dry eye, one of the most frequent ocular surface diseases, is caused by complex ocular function and mechanism disorders. Currently, no uniform standard diagnosis of dry eye has been established. Traditional clinical examinations provide inaccurate measurement and poor reproducibility due to various factors. Anterior segment optical coherence tomography (OCT) is applicable in the diagnosis of dry eye due to its high resolution, non-invasiveness, good accuracy, and repeatability.

[Comparison of deficits in visual cortex between anisometropic and strabismic amblyopia by fMRI retinotopic mapping].

OBJECTIVE: To study the neural mechanism of visual cortical deficits between anisometropic and strabismic amblyopia comparatively by BOLD-fMRI retinotopic mapping. METHODS: Ten anisometropic amblyopes, 10 strabismic amblyopes and 9 normal subjects underwent fMRI with retinotopic mapping and luminous spots stimuli (spatial frequency: 6 cpd, contrast: 0.5). 1.5T MRI system was used to obtain functional images of visual cortex. Responses in primary and secondary visual cortex were compared among the dominant (normal subject group), anisometropic and strabismic amblyopic eyes by one-way ANOVA, successively analyzed by paired-samples t test between amblyopic eyes and fellow fixing eyes (anisometropic and strabismic amblyopia group respectively). Their fMRI deficits of amblyopes were analyzed regressively in two amblyopia groups respectively. RESULTS: The result of one-way ANOVA showed significantly a lower activation (average T value) in V1, V2, V3, Vp and V7 visual areas (P < 0.05, P values 0.018, 0.007, 0.002, 0.000, 0.025 respectively) between anisometropic amblyopia and normal group. This was in accordance with the result of paired-samples t test between amblyopic eyes and fellow fixing eyes in anisometropic amblyopia group (P < 0.05, P values 0.035, 0.007, 0.020, 0.009, 0.023 respectively). Statistical difference was found in V1, V2 and Vp areas between strabismic amblyopia and normal group (P < 0.05, P values 0.010, 0.007 & 0.003 respectively). The paired-samples t test in strabismic amblyopia group showed statistical difference only in V2, Vp areas (P < 0.05, P values 0.026 and 0. 009 respectively. ). So the two results were discordant. Between the two amblyopic groups, there was no statistical difference (P > 0.05) except in V7 area (P < 0.05, P value = 0.048). There was no causal relation between the primary visual cortical deficits and the secondary cortex in amblyopia (P > 0.05). CONCLUSION: Anisometropic amblyopia and strabismic amblyopia both have functional deficits in the primary and secondary visual cortex. The neural mechanism of secondary visual cortical deficits may be more complex than decreased cortex activation induced by the deficit of primary cortex. In the primary cortex, strabismic amblyopia and anisometropic amblyopia have neuronal deficits and/or abnormal interaction. In addition, strabismic amblyopia may also have suppressive influences of the fixing eyes upon the amblyopic eyes. Anisometropic amblyopia has the neural undersampling at a high spatial frequency in the secondary visual cortex as compared to amblyopic amblyopia.

[Experimental study of suppression of reactivation of herpes simplex virus type 1 by cyclooxygenase 2 inhibitor with acyclovir].

OBJECTIVE: To study whether the cyclooxygenase 2 (COX-2) inhibitor can block the herpes virus reactivation and whether the combination of COX-2 inhibitor with acyclovir can enhance the inhibition of virus reactivation. METHODS: It was a experimental study. Mice were randomly divided into six groups. Five groups were HSV-1 infected mice, which included: group A, treated with lornoxicam and acyclovir; groups B and C, treated with lornoxicam or acyclovir, respectively; groups E and F were injected with saline as the untreated control groups. The sixth group was uninfected mice as the control group. All groups were undergone to reactivate the herpes virus by UV-B except group F. The shedding of the virus was determined by cultures of ocular swab or ganglion homogenates with indicator cells. RESULTS: The rates of corneas and ganglia containing the infectious virus in the groups A, B and C were significantly lower than those in the control group D, (cornea: 2XA-D = 36.88, XB-D = 22.43, X2C-D = 20.32, P < 0.05, ganglia : X2A-D = 49.91 X2B-D =29. 16,X2C.D = 24.89, P < 0.05). Combined use of these two drugs in group A showed no significant statistical difference as compared with using them separately in the cornea culture (X2A-B= 2.75, X2A-C = 3.66, 0. 05 < P < 0.1), but there was significant difference in trigeminal ganglia culture (X2A-B = 4.78, 2XA-c = 6. 97, P < 0.05). CONCLUSIONS: These experiments demonstrate that a selective COX-2 inhibitor can suppress UV-B-induced herpes virus reactivation in the cornea and nervous system. A combination of acyclovir does not significantly enhance the inhibition of virus reactivation by lornoxicam. These results provide a new method to prevent the recurrence of HSK.