Volume 51 ·  Issue 05 ·  2015

Retina is the classic"neurovascular coupling" tissue, and coordinate the bioactivity of neurobiology and retinal blood flow. Müller glia cells span the entire thickness of the tissue, and ensheath all retinal neurons and microvascular of the retina. This morphological relationship is reflected by a multitude of functional interactions between neurons and blood-retinal barrier, and play fundamental roles in diabetic retinopathy. However, in recent studies, the mechanisms of Müller glia cells in retinal neurodegeneration and microcirculatory abnormalities of diabetic retinopathy are underestimating. Therefore, the present article reaffirms the interrelationship between Müller glia cells and diabetic retinopathy to draw the attentions of researchers. (Chin J Ophthalmol, 2015, 51:321-322)

To investigate the association between the variable number of tandem repeats (VNTR) polymorphism 4a/b in the endothelial nitric oxide synthase (eNOS) gene and diabetic retinopathy (DR) in patients with type 2 diabetes mellitus.

cross-sectional study. A total of 278 type 2 diabetes patients were recruited, of whom 130 had DR, and 148 had diabetes without retinopathy (DWR). Of the 130 patients with DR, 34 had proliferative DR (PDR) and 96 had non-proliferative DR (NPDR). A number of 223 volunteers without diabetes from the same area were recruited as the control group. PCR and agarose gel electrophoresis methods were adopted to determine the 4a/b polymorphism genotypes of the eNOS gene. Statistical analysis was performed using the R statistical analysis package. Genotype distribution was compared using the χ ² test. Numerical data were examined by Student t test. Genotypes and allele frequencies between cases and controls were compared using the χ ² test or Fisher's exact test. Odd ratios (OR) and 95% confidence intervals (CI) were calculated according to the Woolf's equation.

The frequencies of minor alleles (a) were 10.8% and 11.5% in the DR and DWR group, respectively. There were no statistical differences between the two groups (χ²=0.07,P=0.789). Also there were no statistical differences (χ²=0.88;P=0.643) in the distributions of the genotypes between DR group (bb 78.5%, ab 21.5%, aa 0.0%) and DWR group(bb 77.7%, ab 21.6%, aa 0.7%). Statistical differences were found in the frequencies of alleles, and the distributions of genotypes between diabetes group and the control group (χ²=8.75, 10.39,P=0.003, 0.006). However, after adjustment for age, blood pressure, cholesterol concentration, blood-fat and so on, it became insignificant(χ²=0.97, 1.25,P=3.224, 0.812). In the multiple regressions model including clinic factors such as the age of onset of diabetes, urinary albumin, insulin using, creatinine, glycated hemoglobin and fast glucose, no evidence showed that eNOS gene VNTR 4a/b was associated with diabetic retinopathy (OR=0.37, 95%CI: 0.15- 0.95).

There was no significant association between eNOS gene VNTR 4a/b polymorphism and diabetic retinopathy (DR) in patients with type 2 diabetes mellitus. (Chin J Ophthalmol, 2015, 51:338-343)

To formulate and evaluate polymeric liposomes(PL) nanoparticles as a novel non-viral gene delivery. To explore its applicability and feasibility as a non-viral vector for gene transportation.

Experimental study. To construct the orongoxygen induced retinopathy(OIR)mouse (C57BL/6J) model on the basis of improved Smith's methods. Western blot was used to measure VEGF protein expression in retinal tissue at P17 and P22. HE staining and fluorescein-dextran angiography of retinal vascular were performed to observe the morphologic alterations of retinal neovascularization. Frozen-section was used to show the membrane translocation of PL.

In fluorescence angiograms, irregular neovascularization and fluoresce leakage were observed in OIR model. The results of Western blot showed that VEGF protein in retinal tissues were significantly different among groups(F=158.207,P=0.000) at P17 and P22(F=25.695,P=0.000). The protein level was lower in both PL(0.70±0.03) and Lipo group (0.66±0.04) at P17 (P=0.092), and the lower level was presented at P22 in PL group (0.50±0.03) than in Lipo group(0.53±0.05) (P<0.05). HE staining were performed to observe the significantly improvements of retinal neovascularization in PL(28.0±3.44) and Lipo group(24.50±3.06) at P17. Moreover, inhibitory effects maintained at P22 in PL group (11.70±3.09) as HE staining showed. Fluorescein angiography of retinal vascular showed retinal non-perfusion and neovascularization areas were smaller in both PL and Lipo group at P17. Frozen-section examination showed the property of membrane translocation. GFP expression could be seen in vitreous cavity just at first day post-intravitreal administration in PL and Lipo group, which could reach their peaks in external retina nearby RPE layer at P17, remaining at P22 in PL group.

The PL performed excellent ability of membrane translocation and it was a kind of slow steady released gene vector.(Chin J Ophthalmol, 2015, 51:344-350)

To investigate the mediation of HIF-1α siRNA to the leukocyte adhesion and myeloid cell's activity in rat's retina at early stage of diabetic retinopathy.

Experimental study. HIF-1α specific siRNA expression vector pSUPERH1-siHIF1α was constructed by gene recombination. The rat diabetic model was induced by intraperitoneal injection of streptozotocin. After 2 months of diabetes induction, 27 diabetic rats were randomly chosen and assigned to 3 groups, including diabetes and phosphate buffered saline (PBS) vitreous injection group (group B), diabetes and pSUPERH1-siHIF1α vitreous transfect group (group C) and diabetes and pSUPER-retro vitreous transfect group (group D). Each group had 9 rats. Nine age matched health rats were chosen as control group (group A). Retinal leukostasis was quantified with acridine orange leukocyte fluorography. Retinal myeloid cell activity was measured by enzyme linked immunosorbent assay of myeloperoxidase(MPO). The differences of the mean values among the four groups were analyzed by one-factor analysis of variance. The multiple comparisons of the mean values among the four groups were analyzed by LSD-t analysis.

According to the results of the acridine orange leukocyte fluorography, the numbers of leukocyte adhesion in the four groups were (47.00±3.60), (155.33±9.01), (76.00±9.05), (142.66±10.26), respectively. The differences among them were significant (F=116.25,P=0.00). The number of leukocyte adhesion in the group C was significantly lower than that in group B(LSD-t test,P=0.00, 95%CI: 3.56–95.10). The levels of retinal MPO in the four groups were (17.24±1.13), (31.32±2.53), (21.35±1.06), (31.33±1.26) μg/L, respectively. The differences among them were significant( F=58.68,P=0.00). The level of retinal MPO in the group C was significantly lower than that in group B(LSD-t test,P=0.00, 95%CI: 6.92–13.01).

HIF-1α siRNA may play a role in the mediation of the leukocyte adhesion and myeloid cell's activity in rat's retina at early stage of diabetic retinopathyin vivo.(Chin J Ophthalmol, 2015, 51:351-355)

To investigate whether ranibizumab can penetrate into the retina after subconjunctival injection in a rabbit model.

Experimental study. Fifty-six New Zealand rabbits were randomly divided into four groups: control group (3), saline subconjunctival injection group (3), ranibizumab intravitreal injection group (25) and ranibizumab subconjunctival injection group (25). Each rabbit received single injection in right eye. Ranibizumab's location and concentrations in the retina and aqueous humor were determined by immunofluorescence staining and ELISA at 1, 2, 4, 8, 12 weeks after injection. The comparison of ranibizumab concentration data was analyzed byt-test.

The concentrations of aqueous humor in intravitreal injection group, determined by ELISA, were (389.67±22.55), (319.33±17.93), (22.67±3.06), (9.67±1.53) and (7.33±2.18) mg/L at 1, 2, 4, 8, 12 weeks respectively. Concentrations of subconjunctival injection group were (53.67±3.21), (12.67±3.06), (8.33±1.53), (2.66±2.08) mg/L at 1,2,4,8 weeks and had a statistical difference compared with intravitreal injection group at each time point( t=32.96, 38.39, 7.67, 11.07,P<0.05). But there was no detection at 12 weeks. Similar in retina immunofluorescence staining results, the ranibizumab positive signals were detected in all the time points except the last one in subconjunctival injection group.

Subconjunctival ranibizumab injection may be able to penetrate into retina. (Chin J Ophthalmol, 2015, 51:356-359)

The purpose of the current research was to investigate the NDP (Norrie disease protein) gene in one Chinese family with Norrie disease (ND) and to characterize the related clinical features.

Clinical data of the proband and his family members were collected. Complete ophthalmic examinations were carried out on the proband. Genomic DNA was extracted from peripheral blood leukocytes of 35 family members. Molecular analysis of the NDP gene was performed by polymerase chain reaction and direct sequencing of all exons and flanking regions.

A hemizygous NDP missense mutation c.362G> A (p. Arg121Gln) in exon 3 was identified in the affected members, but not in any of the unaffected family individuals.

The missense mutation c.362G> A in NDP is responsible for the Norrie disease in this family. This discovery will help provide the family members with accurate and reliable genetic counseling and prenatal diagnosis.(Chin J Ophthalmol, 2015, 51:360-363)

Analysis ophthalmic manifestations in acquired immune deficiency syndrome(AIDS) patients with cryptococcal meningitis.

Retrospective study. Forty AIDS patients (including 32 men and 8 women) with cryptococcal meningitis were studied. The age of the patients varied from 11 to 67 years, average on (38±12) years (mean±standard deviation). All the patients underwent detailed ocular examinations including corrected visual acuity, eye movement, intraocular pressure, slit lamp microscope, indirect ophthalmoscope and color fundus photography. The CD₄⁺ T cell count was evaluated and Lumbar puncture was done to examine the cerebral spinal fluid(CSF). Eighteen patients were followed up for a period between 2weeks to 4years. Four patients died during hospitalization. The remaining 18 patients failed to be followed up due to moving away.

Binocular diplopia were present in 3 patients. It showed Binocular or monocular abducens nerve palsy. Papilledema were found in 37 eyes of 19 cases. One person had unilateral papilledema. Among 19 cases, 24 eyes of 12 cases were accompanied with peripapillary hemorrhages and 7 cases of 13 eyes without peripapillary hemorrhages. Optic atrophy occurs in 6 cases of 12 eyes and multifocal choroiditis in 2 cases of 4 eyes. Twenty-seven eyes of 14 patients had normal fundus or cytomegalovirus retinitis(CMVR) only.

AIDS patients with cryptococcal meningitis merger may be accompanied by a variety of eye complications. Papilledema are the most common manifestations. (Chin J Ophthalmol, 2015, 51:364-368)

To investigate the contributions of human rods and cones pathway to different components of oscillatory potentials (OP) in time and frequency domain.

Case-control study. Twenty subjects were divided into two groups, normal groups (NG) and cones pathway abnormal groups (CAG). All eyes were investigated by dark-adapted (DA) and light-adapted (LA) 3.0 ERG recommended by ISCEV. Data were output into the computer and processed and analyzed by the software Matlab7.0. First, to extract the OP by filter, then to get the frequency-amplitude relationship by FFT, after that the relationship was fitted by equations and lastly we statistic and analyze the parameters gotten from the equations.

Compared with normal group[(48.63±4.29), (158.00±32.75), (69.27±30.31), (38.5±15.28) μV], the amplitudes of the first two components of dark-adapted OP in the CAG[(4.12±3.20), (71.25±25.43), (48.96±20.05), (36.84±14.26) μV] were significant decreased( t=16.68,5.77,P<0.01). Frequency domain of LA and DA OP in the two groups was comprised with two components (harmonic and subharmonic). Compared with normal group, harmonic components of CAG were dramatic decreased (t=2.72,P<0.05;Z=-2.24,P<0.05). The value of subharmonic component in CAG was lowest in DA OP compared with NG (t=4.20,P<0.005).

Cones and rods pathway all contributed to the DA and LA OP Cones pathway mainly contributes to the earlier and faster components of OP while the rods pathway to the later and slower components. (Chin J Ophthalmol, 2015, 51:369-373)

Ataxia-telangiectasia mutated(ATM) gene could cause ataxia telangiectasia which is an autosomal recessive disease. The ATM protein kinase encoded by the ATM gene mainly distributed in nucleus as a master regulator of the DNA damage response and apoptosis via cell signaling pathways. The ATM kinase plays a key role in the pathogenesis of cellular senescence and tumor genesis. Recently, some studies have indicated that ATM protein kinase is involved in pathological neovascularization, suggesting that it could be a novel potential therapeutic target in diseases associated with pathological angiogenesis.(Chin J Ophthalmol, 2015, 51:391-394)

There are a variety of genetic eye diseases. In the past years, many methods such as linkage analysis and association analysis have been used to study these diseases and lots of achievements have been made. With the development of the second-generation sequencing technology, DNA sequencing has become much more efficient and cheaper. Exome trapping, combining with the second-generation sequencing technology, has become efficient and accurate means to sequence DNA and screen disease-causing genes. This review outlines the research progresses in eye inherited diseases, the methodological characteristics of second-generation sequencing and exome trapping and their applications in genetic eye diseases.(Chin J Ophthalmol,2015,51:395-400)