The association of lumican polymorphisms and high myopia in a Southern Chinese population.

AIM: To investigate the correlation between lumican (LUM) gene and high myopia in a Southern Chinese population. METHODS: The study comprised of 95 high myopia patients with a spherical equivalent ≤-6.5 diopters (D). The control group recruited 95 individuals with a spherical equivalent ranging from -0.5 D to +0.5 D. Direct sequencing was used to detect the single nucleotide polymorphisms (SNPs) of LUM gene in coding region. Genotype distributions were tested for Hardy-Weinberg disequilibrium. Genotypic and allelic frequencies were analyzed through Chi-square test or Fisher's exact test. RESULTS: We identified 3 SNPs of the LUM gene: LUM c.32 (rs577456426), LUM c.507 (rs17853500) and LUM c.849 (rs181915277). Among the three SNPs, the genotype and allele frequencies of rs17853500 showed a significant difference between patients and control subjects (P<0.05). However, there were no significant differences in rs181915277 and rs577456426 between the two groups (P>0.05). CONCLUSION: LUM c.507 polymorphism may be a risk factor for the pathogenesis of high myopia in the Southern Chinese population.

Lycium barbarum polysaccharides protected human retinal pigment epithelial cells against oxidative stress-induced apoptosis.

AIM: To investigate the protective effect and its mechanism of lycium barbarum polysaccharides (LBP) against oxidative stress-induced apoptosis in human retinal pigment epithelial cells. METHODS: ARPE-19 cells, a human retinal pigment epithelial cell lines, were exposed to different concentrations of H2O2 for 24h, then cell viability was measured by Cell Counting Kit-8 (CCK-8) assay to get the properly concentration of H2O2 which can induce half apoptosis of APRE-19. With different concentrations of LBP pretreatment, the ARPE-19 cells were then exposed to appropriate concentration of H2O2, cell apoptosis was detected by flow cytometric analysis. Expression levels of Bcl-2 and Bax were measured by real time quantitative polymerase chain reaction (RT-PCR) technique. RSULTS: LBP significantly reduced the H2O2-induced ARPE-19 cells' apoptosis. LBP inhibited the H2O2-induced down-regulation of Bcl-2 and up-regulation of Bax. CONCLUSION: LBP could protect ARPE-19 cells from H2O2-induced apoptosis. The Bcl-2 family had relationship with the protective effects of LBP.

The association of LOXL1 polymorphisms with exfoliation syndrome/glaucoma: Meta-analysis.

AIM: To investigate the association of lysyl oxidase-like 1 (LOXL1) single nucleotide polymorphisms (SNPs) with exfoliation syndrome (XFS)/exfoliation glaucoma (XFG). METHODS: Published manuscripts from PubMed and EMBASE were identified until May 2014. Summary odds ratios (ORs) and 95% confidence intervals (CIs) for LOXL1 (rs1048661, rs2165241 and rs3825942) polymorphisms and the risk of XFS/XFG were estimated using random- or fixed- effect model. RESULTS: The three LOXL1 polymorphisms (rs1048661, rs3825942, and rs2165241) were associated with an increased risk for XFS/XFG among Caucasians, with OR 2.19(1.96-2.45), 8.8 (6.05-12.79) and 3.41 (3.11-3.73), respectively. On the contrast, the rs1048661 and rs2165241, but not rs3825942 polymorphism, have a potential protective effect on XFS/XFG in Asians, with OR 0.06 (0.02-0.18), 0.15 (0.09-0.25), respectively. CONCLUSION: There is strong evidence that LOXL1 polymorphisms are associated with XFS/XFG risk. The strength of risk might be ethnicity-dependent.

Comparison of conventional and directional freezing for the cryopreservation of human umbilical vein endothelial cells.

AIM: To compare conventional slow equilibrium cooling and directional freezing (DF) by gauze package for cryopreservation of human umbilical vein endothelial cells (HUVECs). METHODS: HUVECs were randomly assigned to conventional freezing (CF) and DF by gauze package group. The two groups of HUVECs were incubated with a freezing liquid consisting of 10% dimethylsulfoxide (DMSO), 60% fetal bovine serum (FBS) and 30% Dulbecco's modified Eagle's medium (DMEM) and then put into cryopreserved tubes. CF group, slow equilibrium cooling was performed with the following program: precool in 4°C for 30min, -20°C for 1h, and then immersion in -80°C refrigerator. DF group, the tubes were packaged with gauze and then directional freezing in -80°C refrigerator straightly. One month later, the vitality of HUVECs were calculated between two groups. RESULTS: There was no significant difference in the survival rate and growth curve between CF and DF groups. The DF group was significantly better than CF group in adherent rates, morphological changes and proliferative ability. CONCLUSION: In the conventional cryopreserved method, cells are slow equilibrium cooling by steps (4°C, -20°C and finally -80°C), which is a complicated and time-consuming process. But the improved DF by gauze package method is better than conventional method, for which is convenient and easy to operate.

Differentiation of human amniotic epithelial cells into corneal epithelial-like cells in vitro.

AIM: To explore the feasibility that human amniotic epithelial cells (hAECs) have the potential to differentiate into corneal epithelial-like cells under the microenvironment replicated by spontaneously immortalized human corneal epithelial cells (S-ihCECs). METHODS: hAECs were isolated by enzyme digestion, and flow cytometry was used to analysis the expression of CD29/90/166/73/34 and HLA-DR. Recovered and cultured S-ihCECs, immunocytochemistry was used to detect the expression of CK3/12. The proliferation of S-ihCECs handled by different concentrations of mitomycin was detected by CCK-8. The proliferation of hAECs cultured by S-ihCECs culture media collected at different time was analyzed by CCK-8. After filtered out the optimal conditions, we collected S-ihCECs culture media for 5 days, then prepared conditioned medium to incubate hAECs, inverted phase contrast microscope and scanning electron microscope were used to observe the change of morphology in hAECs. Quantitative real-time reverse transcription-polymerase chain reaction (QRT-PCR) was carried out to evaluate the expression of Oct-4, NANOG, PAX6, and CK12 in the differentiation period. Immunocytochemistry and western bloting were used to detect the expression of CK3/12. RESULTS: The culture media collected every 12h, from 20µg/mL mitomycin pretreatment S-ihCECs could significantly promote the proliferation of hAECs. In the period of differentiation, the morphology of differentiated hAECs was obviously different compared with the control group, and the distinctive CK3/12 for corneal epithelial cells was detected. CONCLUSION: This study showed that hAECs can differentiate into corneal epithelial-like cells by in vitro replication of the corneal epithelial microenvironment, using the culture media collected from S-ihCECs, and it is possible that S-ihCECs culture media could be used in corneal tissue engineering.

Comparison of trabeculectomy and trabeculectomy with amniotic membrane transplantation in the same patient with bilateral glaucoma.

AIM: To observe effects of trabeculectomy with amniotic membrane transplantation (AMT) in controlling postoperative intraocular pressure (IOP) in patients with medically uncontrolled glaucoma. METHODS: This study included adult patients with requiring bilateral glaucoma surgery. Each patient underwent trabeculectomy (Non-AMT group) in one eye and with AMT (AMT group) in the other eye according to randomized principle. Success was defined as intraocular pressure (IOP)<21mmHg without any anti-glaucoma medications at 24 months follow-up. The two groups were compared in terms of IOP, complications and success rate. RESULTS: Thirty-four eyes of 17 patients were investigated in this study. There was no statistically signifcant difference in pre-operative IOP between the two groups. The mean IOP was lower in AMT group compared with Non-AMT group on follow up months 12, 18, and 24.Postoperative complications were more frequent in Non-AMT group (35.3%, 6/17) compared with AMT group (5.9%, 1/17). The success rate of surgery was 88.2% (15/17) in Non-AMT group and 100% (17/17) in AMT group. CONCLUSION: Trabeculectomy with AMT is an effective procedure to reduce IOP and complications, thereby improving surgical success rates.

New mucosal flap modification for endonasal endoscopic dacryocystorhinostomy in Asians.

AIM: To describe a simple modification of fashioning the mucosal flap for endonasal endoscopic dacryocystorhinostomy (EES-DCR) in Asians and investigate its efficacy. METHODS: A total of 120 patients with unilateral primary chronic dacryocystitis (PCD) were randomized into two groups: the new shaped nasal mucosal flap group (group A) and the removed nasal mucosal flap group (group B). All patients underwent standard EES-DCR. Patients in group A were performed a new shaped nasal mucosal flap covering the bared bone around the opened sac and those in group B was removed the nasal mucosal flap uncovering the bared bone. Patients were followed up for one year. The occurrence of granulation tissue, the proliferation of scar tissue and success rate of EES-DCR was compared. RESULTS: In the present study, complete postoperative data were acquired from 54 patients in group A and from 57 patients in group B. During process of review, the occurrence of granulation tissue was at the ostium margins account for 15% (8/54) in group A and 39% (22/57) in group B (P<0.05). At the one-year review, scar tissue was present in 5 patients in group A compared with 18 in group B (P<0.05). The success rate of EES-DCR was 98% (53/54) in group A and 84% (48/57) in group B (P<0.05). CONCLUSION: The simple modification of fashioning nasal mucosal flap can effectively cover the bared bone around the opened sac and reduce formation of granulation tissue, lessen the risk of scar tissue formation and closure of ostium, thus improve the success rate of EES-DCR in Asians.