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Objective To investigate the protective role of light preconditioning in retinal photoreceptor cells and the underlying mechanisms after light damage.Methods Together 42 BALB/c mice were randomly divided into normal control group,light damage group,light preconditioning + light damage group and light preconditioning group.Mice in the light damage group were exposed to 4000 Lux intensity of cool white fluorescent light for 4 h continually;mice in the light reconditioning + light damage group were maintained in 600 Lux cyclic bright light for preconditioning (12 h ON and 12 h OFF) for 6 days,and then exposed to 4000 Lux bright-light for the induction of the damage;mice in the light reconditioning group were maintained in 600 Lux cyclic bright light for preconditioning (12 h ON and 12 h OFF) for 2 days,4 days,6 days.Then the function and morphology of retinal photoreceptor cells were detected by flash electroretinogram (FERG) and histopathological examination in the normal control group,light damage group and light preconditioning + light damage group,while real-time polymerase chain reaction (PCR) was used to detect the mRNA relative expression of leukemia inhibitory factor (LIF) and Western blot analysis was used to detect the phosphoprotein relative expression of signal transducer and activator of transcription 3(STAT3) in the light preconditioning group.Results FERG results showed the amplitudes of scotopic ERG a wave of the light damage group were decreased when compared with the normal control group,with significant difference (P =0.000).Compared with the light damage group,the amplitudes of scotopic ERG a wave of the light preconditioning + light damage group were increased significantly (P =0.000).Histopathological examination results showed that the number of photoreceptor nuclei in the light damage group was decreased compared with the normal control group,and the difference was statistically significant (P =0.000).Compared with light damage group,the number of photoreceptor nuclei in light preconditioning + light damage group was increased significantly (P =0.000).Real-time PCR results showed light preconditioning enhanced the LIF mRNA relative expression in a time-dependent manner (F=128.776,P =0.000).Western blot results showed light preconditioning up-regulated the phosphoprotein relative expression of STAT3 protein in a time-dependent manner (F =73.493,P =0.000).Conelusion Light preconditioning can protect retinal photoreceptor cells against light damage which may results from the activation of LIF/STAT3 signaling pathway.
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Background Retinal retinoic acid (RA) plays an important role in the formation of the lensinduced myopia.However,it is not clear how RA transfer the myopic signal to choroid throughout the retinal pigment epithelium (RPE) barrier.Objective The aim of this study was to investigate the effect of all-trans retinoic acid (atRA) on the barrier of RPE in lens-induced myopic eye of guinea pig.Methods Thirty left eyes of 30 21-dayold clean guinea pigs were randomized into normal control group and the model group.The models of out of focus were induced by covering of-6.00 D concave lens on the left eyes for 15 days.Radius of corneal curvature was measured using corneal curvimeter,and diopeter of the guinea pig was examined by mydriatic optometry.The length of ocular axis was detected by A-sonography.The animals were sacrificed and the retinas of the left eyes were isolated for the culture and passage of RPE cells.The third generation of cells were incubated Millcell-PET microporous film,and atRA at the concentration of 1 × 10-6,1 × 10-7,1 × 10-8 and 1 × 10-9 mol/L was added to the micropore respectively for 12 hours,and the micropores with equal-solvent served as negative control group.Methyl thiazolyl tetrazolium (MTT)colorimetric method was used to detect the survival rate of the cells.Subsequently,the transepithelial electrical resistance (TER) of the monolayer cells was determined with CN10-EVOM2 resistance measuring meter.The vesicular transport change of RPE membrane in different groups was evaluated by FM1-43 fluorescence staining.Results The mean diopter was (-2.20±0.95) D in the models,and that in the controls was (+ 1.15 ±0.30) D,with a significant difference between them (t =14.57,P＜ 0.01).The axial length was (8.24 ± 0.09) mm in the models and it was significantly longer than (7.81±0.05) mm in the controls (t=17.20,P＜0.01).RPE cells grew well to form a monolayer in Millcell culture pool after one week.After 24 hours of the atRA treatment,the survival rate of RPE cells reduced gradually with the increase of atRA concentration with the highest rate in the 1 × 10-9 mol/L atRA group (93.3 ％) and followed by the 1 × 10-8 mol/L atRA group (88.2％).More than half of the cells dead in the 1 × 10-6mol/L and 1 × 10-7mol/L atRA groups (53.8％ and 47.1％).Significant differences in the TER value and fluorescence staining intensity of the cells were seen among the various groups (F =43.89,P =0.00 ; F =26.13,P =0.00),with the maximal values in the 1 × 10-8mol/L atRA group.The FM1-43 fluorescence located on the cellular membrane and cytoplasm.Conclusions AtRA can increase the functional state of tight junction and vesicular transport,which regulated the RPE cell barrier in the guinea pig.
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<p><b>OBJECTIVE</b>To study the inhibition effect of HIF-1α specific siRNA expression vector pSUPERH1-siHIF-1α on retinal neovascularization in a mouse model of retinopathy of prematurity (ROP).</p><p><b>METHODS</b>The mouse model of ROP was prepared by the method Smith described. Forty-eight ROP mice were randomly divided into two groups: an experimental group that was intravitreously injected with pSUPERH1-siHIF-1α and a control group that was injected with pSUPER retro vector. The levels of HIF-1α and vascular endothelia growth factor (VEGF) in the retina were examined by Western blot. The retinal neovascularization was evaluated by angiography using FITC Dextran and quantitated histologically.</p><p><b>RESULTS</b>The levels of HIF-1α and VEGF in the retina in the experimental group were reduced 90% and 65% respectively compared with those in the control group. Meanwhile, the number of retinal neovascular endothelial nucleus outbreaking the inner limit membrane in the experimental group was significantly reduced compared with that in the control group.</p><p><b>CONCLUSIONS</b>The development of retinal neovascularization of ROP can be markedly inhibited by RNA interference targeting HIF-1α.</p>
Subject(s)
Animals , Humans , Infant, Newborn , Mice , Disease Models, Animal , Hypoxia-Inducible Factor 1, alpha Subunit , Genetics , Mice, Inbred C57BL , RNA, Small Interfering , Genetics , Retinal Neovascularization , Retinopathy of Prematurity , Therapeutics , Vascular Endothelial Growth Factor AABSTRACT
Background Nearly over 40 years have elapsed since the original findings of visual cortical plasticity,but none of drug has been found for curing amblyopia effectively. Objective The goal of this study was to investigate the effects of different dose of levodopa on flash visual evoked potential(F-VEP)and morphology of visual cortex cells in monocular deprivation rat and explore the possible mechanism of curing amblyopia.Methods Monocular deprivation model were established by suturing eyelids of 30 2-week-old Sprague Dawley(SD)rats for 4 weeks.The 30 SD rats were then divided into 3 groups randomly and 10 rats for each group.Normal saline.20 ms/kg levodopa,80 ms/kg levodopa were intragastrically administered once per day after modeling respectively for 4 weeks.F-VEP was recorded after establishment of model and administration of drug respectively.The rats were sacrificed and the visual cogex was obtained for histological examination,and TUNEL technique was used to assess the structural change of visual cortex.Results The latency of P1 wave was significantly longer in the deprived eye than the normal eyes(P<0.05).After administration of levodopa,the latent periods of Pl wave in the deprived eye were obviously shortened in comparison with before administration of levodopa in 20 ms/kg and 80 mg/kg levodopa group (P<0.05).The difference values of latent period of P1 wave between before and after administration of drug showed statistically significant change in three groups(P<0.05).No evidently alterations were found in the amplitude differences of N1 P1 and P1 N2 waves among three groups(P>0.05).The number and structure of neurons in contralateral visual cortex of non-deprived eye were normal.However,the numbers of neurons in deprived eye were significantly less and presented the signs of para-apoptosis in normal saline group.In 20 mg/kg levodopa groups,the alterations of number and morphology in neurons of rat visual eogex were slight.TUNEL assay revealed that the numbers of positive neurons in contralateral visual codex of non-deprived eye were 2.20±1.23.while those in deprived eye were 53.7±9.36,27.20 4±5.96 and 10.70±3.23 in normal saline group,20 mg/kg and 80 mg/kg levodopa group respectively,showing a significant difference among them(P>0.05).After usage of levodopa,the numbers of positive neurons was negatively correlated with the difference value of P,latent period of VEP(r=-0.815,P=0.000).Conclusion Levodopa has a therapeutic effect on rat deprived eye,and its possible mechanism is inhibiting the para-apoptosis of neurons and participating in the development and plasticity of visual system.
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Background As a main suppressing neurotransmitter in visual system,gamma-aminobutyric acid (GABA) participates in the transmission and regulation of visual information.GABA and dopamine (DA) coexist in the visual cortex,and their mutual effects should be clarified.Objective This study was to investigate the effect of DA on GABA-activated current in vitro in cultured visual cortical neurons of rats.Methods Neutrons from visual cortex of clean neonatal rats were isolated and cultured by explant culture method.The neutrons cultured for 11 -to 14- days were collected for the record of whole cell currents of GABA-A (IGABA) channels in vitro using patch clamp technique.The DA solution (100mmol/L),SKF38393 (10mmol/L) solution and quinpirole solution(10mmol/L) were prepared with double distilled water and then the extracellular fluid was added to different concentrations.The IGABA changing rate under the action of SKF38393+SCH23390,SKF38393+Quinpirole for different time was recorded respectively and compared with that of action of DA,SKF38393,SCH23390,Quinpirole.The IGABA activated by extracellular fluid along served as control.Results The IGABA was significantly attenuated after activated by ≥10μmol/L of DA or SKF38393 separately in comparison to that of extracellular fluid action (P＜0.05).In various time of action,there were obviously differences in IGABA between DA or SKF38393 action and extracellular fluid (P＜0.05,P＜0.01).No evident change in IGABA changing rate was found after only SCH23390 action in comparison with extracellular cells (P＜0.05).However,after combination of SCH23390 and SKF38393,IGABA changing rate reduced by 19.49%.No significant differences were found in the changing rates of IGABA among different concentrations of quinpirole action groups compared with extracellular fluid group (P＞0.05);while when quinpirole was combined with SKF38393,the IGABA was elevated in comparison with only SKF38393 action group (P＜0.05).Conclusion Dopamine participates in the transfer and regulation of visual information through suppressing GABA-activated currents from neutrons of visual cortex at time-dependent manner in vitro.
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OBJECTIVE@#To investigate the effect of regulation of VIPhybrid, an unselective antagonist of vasoactive intestinal peptide receptors (VIPR), on the formation and development of form deprivation myopia (FDM) in chick and the expression of protein and mRNA of VIP on the retina and choroids of in chicks.@*METHODS@#Seventy-two 1-day-old yellow healthy leghorn chicks were assigned into 6 groups (12 in each group). Eyes in Group I were covered on the right as a blank control group. Eyes in GroupII were those eyes having been injected with 20 microL saline into vitreous cavity and then covered as a negative control group. Eyes in GroupIII,IV and V were injected with 20 microL VIPhybrid with low (3*10(-12) mol/L), middle (3*10(-10) mol/L) and high (3*10(-8) mol/L) dosage into vitreous cavity and then covered as experimental groups. The above groups had been continuously covered for 1 week. Eyes in Group VI were uncovered and uninjected as a normal control group. Diopter was detected using retinoscopic refraction. The eyeball axis was determined using ophthalmological ultra-A. The expression of protein and mRNA of VIP on retina-choroids-sclera were investigated by SP immunohistochemistry staining and RT-PCR.@*RESULTS@#Form deprivation for 1 week induced high myopia eyes and elongated eyeball axis in GroupI and GroupII, and there was no difference between the 2 groups (P>0.05). The diopter and eyeball axis were significantly reduced in Group III, IV, and V as compared with Group I and II (P<0.01), but the diopter was higher and the eyeball axis was longer than those of Group VI. The diopter and eyeball axis had negative correlation with the concentration gradient of VIPhybrid. The expressions of protein and mRNA of VIP in Group III, IV, and V were down-regulated as compared with those of Group I and I I(P<0.01)and also down-regulated with the increase of concentration of VIPhybrid.@*CONCLUSION@#VIPhybrid can decrease the development of FDM in chicks, which may provide a new pathway for drug therapy of myopia in human beings.
Subject(s)
Animals , Animals, Newborn , Chickens , Myopia , Metabolism , RNA, Messenger , Genetics , Receptors, Vasoactive Intestinal Peptide , Recombinant Fusion Proteins , Pharmacology , Retina , Metabolism , Vasoactive Intestinal Peptide , GeneticsABSTRACT
OBJECTIVE@#To construct the recombinant adeno-associated virus(rAAV) vector plasmid pSNAV2.0-TK containing HSV1-TK gene, to produce recombinant adeno-associated virus rAAV2/HSV1-TK, and to detect the integration and expression of HSV1-TK gene in lens epithelial cells transfected by rAAV2/HSV1-TK, and to provide foundation for gene therapy of posterior capsular opacification.@*METHODS@#The recombinant vector plasmid constructed by gene recombinant technology was analyzed by PCR and restriction enzyme digestion. The cell strain BHK-21/TK was screened by G418 after the plasmid was transfected into BHK-21 cells,with the helper virus HSV1-rc/UL2 to produce the recombinant virus rAAV2/HSV1-TK. The purity of rAAV2/HSV1-TK was detected by SDS-PAGE and HPLC, and the titre of rAAV2/HSV1-TK was observed by dot blot hybridization. The HSV1-TK gene in lens epithelial cells transfected by rAAV2/HSV-TK was investigated by PCR and RT-PCR.@*RESULTS@#The recombinant plasmid proved successful by PCR and restriction enzyme digestion. The recombinant virus rAAV2/HSV1-TK was produced successfully and its titre was 1 x 10(12) v.g./mL by dot blot hybridization. The HSV1-TK gene was integrated and expressed in lens epithelial cells.@*CONCLUSION@#The recombinant adeno-associated virus vector plasmid containing HSV1-TK gene is successfully constructed, and high titre recombinant adeno-associated virus (rAAV2/HSV1-TK) is obtained. The HSV1-TK gene in lens epithelial cells is expressed after being transfected by rAAV2/HSV1-TK.
Subject(s)
Animals , Cricetinae , Rabbits , Cloning, Molecular , Dependovirus , Genetics , Metabolism , Epithelium, Corneal , Cell Biology , Metabolism , Genetic Vectors , Herpesvirus 1, Human , Genetics , Recombinant Fusion Proteins , Genetics , Thymidine Kinase , Genetics , TransfectionABSTRACT
OBJECTIVE@#To explore the relationship between melanin synthesis and the congenital high myopia of albino guinea-pigs.@*METHODS@#Twelve albino guinea-pigs and 12 pigmented guinea-pigs of 220~250 grams (aged 5~6 weeks) were chosen at random. The eyes were examined with retinoscopy, A-scan ultrasonography and vernier caliper. The retinal structures were examined with light and electronic microscope.@*RESULTS@#The diopter was -19.17 D in albino guinea-pigs and +0.63 D in pigmented guinea-pigs on average. Compared with the pigmented guinea-pigs, the axial dimensions of the albino guinea-pigs were elongated. There was significant difference between the albino guinea-pigs and the pigmented guinea-pigs. The retinal thickness, pigment granules and membrane disc of the outer segment of the visual cells decreased in the albino guinea-pigs, and the membrane disc space became narrow. The normal retinal thickness, plenty of pigment granules , membrane disc and wide membrane disc space could be observed in the pigmented guinea-pigs.@*CONCLUSION@#Albino guinea-pigs have high myopia, and pigmented guinea pigs have light hyperopia. There are structural differences in the retina between albino guinea-pigs and pigmented guinea-pigs. The abnormity of albino guinea-pigs provides optical foundation for its high myopia.
Subject(s)
Animals , Albinism , Guinea Pigs , Melanins , Microscopy, Electron, Scanning , Myopia , Metabolism , Random Allocation , Retina , Metabolism , Pathology , Skin PigmentationABSTRACT
OBJECTIVE@#To characterize the antisense c-fos oligonucleotides that control the expression of immediate-early gene c-fos in retina in order to better understand the mechanism by which antisense c-fos oligonucleotides induced myopia. In this study the signal transduction in the pathway linking visual experience and the regulation of the eye's growth was investigated.@*METHODS@#Thirty-one 3-week guinea pigs were assigned into 3 groups: antisense and sense c-fos oligonucleotides were intravitreally injected every 3 days to the eyes of the experimental guinea pigs at different concentrations; and saline vehicle to control guinea pigs in the same way. The refraction and axial length of the eyes were measured before and after the treatment, and the immediate-early gene c-fos expression in the retina was quantified by immunohistochemistry and RT-PCR.@*RESULTS@#The moderate myopia was induced in high (1 nmol) and low (0.1 nmol) level of antisense c-fos oligonucleotide intravitreous injection (-5.425 D and -5.575 D, respectively) compared with the control ateral eyes. The refraction and axial length of the treated eyes increased, and the expression of immediate-early gene c-fos decreased significantly in the antisense c-fos oligonucleotides intravitreously injected eyes compared with the sense c-fos oligonucleotide intravitreously and saline vehicle injected eyes (P0.05).@*CONCLUSION@#The obvious myopia can be induced by antisense c-fos oligonucleotides in guinea pigs; antisense c-fos oligonucleotides inhibit c-fos expression in the retina. Immediate-early gene c-fos may be a potential factor in the prevention of myopia and plays an important role in the signal transduction of the retina.
Subject(s)
Animals , Genes, Immediate-Early , Genetics , Guinea Pigs , Immunohistochemistry , Microinjections , Myopia , Genetics , Oligonucleotides, Antisense , Genetics , Toxicity , Proto-Oncogene Proteins c-fos , Genetics , RNA, Messenger , Genetics , Metabolism , Random Allocation , Retina , Metabolism , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction , PhysiologyABSTRACT
OBJECTIVE@#To evaluate the clinical effects of the mixture of 5-fluorouracil (5-FU) and triamcinolone acetonide on capillary hemangioma of eyelid.@*METHODS@#One hundred and one patients with capillary hemangioma of eyelid were divided into Group A and Group B: Group A was injected with triamcinolone acetonide, and Group B was injected the mixture of 5-FU and triamcinolone acetonide.@*RESULTS@#The cure rate was 68.3%, the total effective rate was 76.0%, and the average course of treatment was (8.1+/-3.4) months for Group A; the cure rate was 90.0%, the total effective rate was 96.6%, and the average course of treatment was (5.1+/-2.3) months for Group B. The therapeutic effect in Group B was better than that in Group A (P<0.05). The treatment period in Group B was shorter than that in Group A (P<0.05).@*CONCLUSION@#5-FU combining with triamcinolone acetonide has not only a better therapeutic effect, but also a shorter period of treatment.
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Female , Humans , Male , Eyelid Neoplasms , Drug Therapy , Fluorouracil , Therapeutic Uses , Hemangioma, Capillary , Drug Therapy , Treatment Outcome , Triamcinolone Acetonide , Therapeutic UsesABSTRACT
OBJECTIVE@#To study the apoptosis of retina and the expression of c-myc protein in form-deprivation myopia.@*METHODS@#Two-day-old chickens were sutured with right eyelid for 4, 8 and 12 weeks. After measurement of refracation, the eyeballs were observed by light microscope and taken photos. Retinal apoptotic cells were measured by TUNEL staining and flow cytometry. C-myc protein were examined by immunohistochemistry and flow cytometry.@*RESULTS@#Lacquer crack lesions were found in sutured eyes at 12 weeks. Apoptotic cells were observed in retinal outer and inner nuclear layer of the sutured eyes at 12 weeks and obvious peak of apoptosis was observed in sutured eyes at 12 weeks. The expression of c-myc protein was significantly more than control eyes at 8 and 12 weeks.@*CONCLUSION@#The apoptosis of retinal was present in form-deprivation myopia with the degeneration of retina. C-myc protein plays an important role in retinal apoptosis of myopia.
Subject(s)
Animals , Animals, Newborn , Apoptosis , Physiology , Chickens , Flow Cytometry , Myopia , Metabolism , Pathology , Proto-Oncogene Proteins c-myc , Genetics , Random Allocation , Retina , Metabolism , PathologyABSTRACT
OBJECTIVE@#To investigate the effect of form-deprivation on level of gelatinase in the posterior sclera in chicks.@*METHODS@#Fifty 1-day-old chicks were monocularly deprived to establish the animal model of form-deprivation myopia (FDM). According to the duration of form-deprivation the experimental chicks were divided randomly and equivalently into 5 groups, which were deprived for 3, 7, 14, 21 and 30 days respectively. Meanwhile the other eyes of the deprived chicks were used as self-control groups and chicks of the same days were chosen randomly as the normal control groups for each FDM group. At each form-deprivation point the changes of degree of diopters and axial length of chicks in each group were recorded. The levels of gelatinase in posterior sclera of the experimental eyes were measured by gelatin enzymography.@*RESULTS@#Compared with the normal and self-control groups, the levels of MMP-2 activity in FDM groups were much higher (P <0.01). With the increase of the time of monocular deprivation these changes became more significant and reached the top after 14 days' deprivation with an inter-group statistical difference (P <0.01). The dynamic changes of MMP-2 activity were the same as those of axial length and degree of diopters in each experimental groups. There was positive correlation between the MMP-2 activity and axial length (r = 0.989, P < 0.01). But there was a negative correlation between the MMP-2 activity and refractive degree.@*CONCLUSION@#Increase of MMP-2 activity in the posterior sclera of chicks would be a direct key factor to trigger sclera ECM remodeling process in chick FDM.
Subject(s)
Animals , Chickens , Gelatinases , Metabolism , Matrix Metalloproteinase 2 , Metabolism , Myopia , ScleraABSTRACT
OBJECTIVE@#To investigate the characteristics of hypermetropic children whose visual acuity (VA) is declined or accompanied by esotropia.@*METHODS@#One hundred and ninety children were given optometry, strabismus degree and binocular vision measurement.@*RESULTS@#Declined VA appeared in 170 children, while esotropia occurred in 173. Sixty-one got binocular single vision, 17 had fusion function, and 11 had stereoaculty. Spherical equivalent had a linear relationship with VA (P 0.05). The influence factors of binocular vision were age of discovery, VA and the strabismus degree, while the stereoaculty was influenced by the strabismus degree, spherical equivalent and VA.@*CONCLUSION@#Low VA and strabismus are the most common complaint in children. Ametropia and strabismus do great harm to juvenile binocular vision, and stereoaculty is damaged seriously. We suggest an early examination of visual function in children.
Subject(s)
Adolescent , Child , Female , Humans , Male , Causality , Esotropia , Hyperopia , Vision, Binocular , Visual AcuityABSTRACT
OBJECTIVE@#To investigate the dynamic expression and significance of vasoactive intestinal peptide receptor 2 (VIPR2) on retina-choroid-clera in high myopia.@*METHODS@#Twenty-one yellow chicks of 1 day old were used in the research. The right eyes were the experimental group, covered continuously for 1 week, 2 weeks and 4 weeks respectively. The left eyes were not covered as the normal control group. Both groups were detected diopter degrees using retinoscopic refraction, determinated eyeball axis using ophthalmology ultra-A, and investigated VIPR2 expression on retina-choroid-sclera in both groups at three stages by SP immunohistochemical staining.@*RESULTS@#The experimental eyes changed from hypermetropia at pre-experiment to high myopia during the experiment stages, and the diopter degrees were deeper and eyeball axis was longer along with the period of being covered. Both groups had strong expression of VIPR2 on photoreceptor-outer segment of the retina and choroids. The expression was down-regulated with the time in both groups. Compared with the control group, VIPR2 expression of the experimental group was significantly up-regulated (P < 0.05).@*CONCLUSION@#Form deprivation could induce high myopia. The expression of VIPR2 existed on photoreceptor-outer segment of the retina and choroids. VIPR2 may play an important role on the formation and development of myopia.