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21.
AIM: To investigate the effects of nintedanib thermo-sensitive hydrogel (NTH) on neovascularization and related markers in corneal alkali burns of Wistar rats. METHODS: NTH was prepared by grinding, and its phase-transition temperature was determined. Thirty specific-pathogen-free Wistar rats served as a model of corneal alkali burn in the right eye were randomly divided into 3 groups (n=10, each): model group treated with 0.9% saline once a day, NTH group with 0.2% nintedanib b.i.d, and dexamethasone (DEX) group with DEX ointment once a day. The left eye of rats served as the controls. The corneal transparency was observed under a slit-lamp microscope, and the area of neovascularization was calculated. On day 7, the rats were sacrificed, and the cornea was removed and embedded with paraffin, then stained with hematoxylin-eosin, and the expression of VEGFR-2 and CD31 in the corneal tissues of each group was detected by immunofluorescence. RESULTS: The phase-transition temperature of nintedanib obtained by grinding was 37°C after adding artificial tears. The results of the alkali burn model indicated that the growth rate of neovascularization in the NTH group was slower than that in the model group, and the neovascularization area was significantly smaller than that in the model group (P<0.05). Moreover. CD31 and VEGFR-2 expression levels in the NTH group were significantly lower than those in the model group. CONCLUSION: NTH becomes colloidal at body temperature, which is beneficial for releasing the drug slowly and can significantly inhibit the neovascularization of corneal induced by alkali burn in rats.  相似文献   
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AIM: To evaluate retinal parameters in a sample of healthy young Caucasian adults to define the normal or physiological range of inter-ocular asymmetry in this particular age and ethnic group. METHODS: Study sample consisted of 37 Caucasian children and young adults aged between 12 and 23y (spherical equivalent from -3.00 D to +4.00 D, anisometropia <0.5 D and axial length differences <0.3 mm). Normal inter-ocular asymmetry values were determined and 95% inter-ocular difference tolerance values were obtained. RESULTS: Statistically significant inter-ocular differences were found in mean (P=0.003) and superior (P=0.008) retinal nerve fiber layer (RNFL) thickness, as well as in central macular thickness (P=0.039), with larger values in the left eye in all instances, and with tolerance limits of inter-ocular asymmetry of -9.00 μm to 6.00 μm, -28.00 μm to 9 μm and -39.00 μm to 29.00 μm, respectively. In addition, statistically significant differences were found between males and females in mean thickness of the RNFL in the right eye (P=0.020). CONCLUSION: The exploration of the normal asymmetries of the retina may be an effective approach to further understand myopia onset and progression, which is particularly relevant in this age group. Differences in instrumentation and sample characteristics compromise direct comparison with published research and warrant the need for further studies.  相似文献   
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病理性近视是全世界范围内引起患者视力下降的主要原因之一,在亚洲国家尤为多见。而脉络膜新生血管是病理性近视的最严重并发症之一,它可以引起眼底黄斑区病变,导致视力下降,出现中心暗点,视物变形,视野缺损等,如长期不治疗可能导致失明。光学相干断层扫描、光学相干断层扫描血管成像、荧光素眼底血管造影等检查方法在诊断病理性近视继发的脉络膜新生血管中起到很大帮助,可以较为明确的显示新生血管的位置,大小等,不论其是否处于活动期。目前对于病理性近视引起的脉络膜新生血管主要治疗方法有光动力治疗及抗血管内皮生长因子(VEGF)治疗,近年来,玻璃体腔内注射抗VEGF药物成为病理性近视与脉络膜新生血管的首选治疗方法,通过减少新生血管的形成,减轻黄斑区水肿,从而达到改善视力及更好的预后效果。论文主要综合整理近期关于病理性近视脉络膜新生血管的诊断及治疗的研究,为临床工作提供帮助。  相似文献   
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Complications from pathologic myopia are a major cause of visual impairment and blindness, especially in east Asia. The eyes with pathologic myopia may develop loss of the best-corrected vision due to various pathologies in the macula, peripheral retina and the optic nerve.Despite its importance, the definition of pathologic myopia has been inconsistent. The refractive error or axial length alone often does not adequately reflect the ‘pathologic myopia’. Posterior staphyloma, which is a hallmark lesion of pathologic myopia, can occur also in non-highly myopic eyes. Recently a revised classification system for myopic maculopathy has been proposed to standardize the definition among epidemiological studies. In this META-PM (meta analyses of pathologic myopia) study classification, pathologic myopia was defined as the eyes having chorioretinal atrophy equal to or more severe than diffuse atrophy.In addition, the advent of new imaging technologies such as optical coherence tomography (OCT) and three dimensional magnetic resonance imaging (3D MRI) has enabled the detailed observation of various pathologies specific to pathologic myopia. New therapeutic approaches including intravitreal injections of anti-vascular endothelial growth factor agents and the advance of vitreoretinal surgeries have greatly improved the prognosis of patients with pathologic myopia. The purpose of this review article is to provide an update on topics related to the field of pathologic myopia, and to outline the remaining issues which need to be solved in the future.  相似文献   
28.
Background: Aniridia is a rare developmental eye disorder characterized by complete or partial iris hypoplasia often accompanied with other ocular changes that affect the cornea, anterior chamber, lens, retina, and optic nerve. Most cases of aniridia are inherited with an autosomal dominant mode of inheritance caused by PAX6 mutations or deletions. To reveal the underlying genetic defect in a four-generation Iranian family with aniridia, we carried out a genetic screening of PAX6.

Methods: Complete ophthalmic examinations were performed for available affected family members. All PAX6 exons and their flanking regions were sequenced for affected individuals. Candidate variation was screened for segregation in the pedigree by Sanger sequencing. Bioinformatics prediction was done to evaluate the deleterious effects of the mutation on protein product. Real-time PCR was used to investigate the impact of the variant on PAX6 mRNA expression.

Results: All patients were diagnosed with isolated aniridia associated with variable phenotypic features including retinal detachment. A novel heterozygous deletion c.320_348delTGTCCGAGGGGGTCTGTACCAACGATAAC (p.Leu107HisfsX16) on PAX6 gene was detected. Decreased mRNA level of PAX6 in the affected individuals indicated that the mutation caused nonsense-mediated mRNA decay (NMD).

Conclusions: To the best of our knowledge, it is the first report on the genetics of aniridia in Iran. Segregation analysis, bioinformatics prediction and confirmation of NMD, all support the proposition that the novel observed PAX6 mutation is the cause of aniridia in the pedigree. Retinal detachment in some of the affected members, which is a rare reported phenotypic feature of aniridia patients, may be associated with this mutation.  相似文献   

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[目的]探讨抑木扶土法治疗视网膜静脉阻塞继发黄斑水肿(macular edema secondary to retinal vein occlusion,RVO-ME)的理论依据及临床疗效。[方法]根据RVO-ME病程迁延、反复发作的特点,通过"土虚木乘""木旺乘土"两个方面,阐述抑木扶土法治疗RVO-ME的理论依据,并阐明抑木扶土方——逍络方的组方意义,举病案佐证。[结果]RVO-ME与肝郁、脾虚有关,临床应用逍络方抑木扶土、活血化瘀治疗效果明显;通过案例证明逍络方能够减轻RVO-ME患者黄斑水肿,提高最佳矫正视力,且长期疗效良好。[结论]抑木扶土法治疗RVO-ME疗效明显,临床应用前景良好,为RVO-ME的治疗提供了新方法。  相似文献   
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