Progress in the studies of etiology,epidemiology and pathogenesis of ocular melanomas

Our population-based epidemiological studies demonstrated that the epidemiological aspects of ocular melanomas are different from those in cutaneous melanoma.The incidences of conjunctival melanoma increased in the past decades and was higher in the South(greater sun exposure),which is consistent with the occurrence of cutaneous melanoma.On the contrary,incidences of uveal melanoma are in the opposite direction of cutaneous melanomas.This indicates that solar radiation does not cause an increase of incidences of melanoma in ocular tissues (uveal melanoma) that are not exposed to solar radiation.Solar radiation increases the incidence of melanoma only in tissues exposed to said radiation,such as in conjunctival and eyelid melanomas.Uveal melanoma incidences in lightpigmented individuals are much greater than in dark-pigmented individuals.This result cannot be attributed to a melanin photo-screening effect,and is possibly related to melanin's biophysical and biochemical effects.The difference in incidences between light-and dark-pigmented individuals in conjunctival melanomas,as well as in vulvar and vaginal melanomas,are much lower than that in the uveal and cutaneous melanomas.This difference may be related to the different histological structures in these melanomas;.conjunctival and vaginal melanomas occur in the mucous membrane,whereas cutaneous melanomas occur in the skin.Recent molecular biological studies indicate that each type of melanoma has its own molecular changes which are different from the others.Therefore,independent studies are required for each type of melanoma to discover their own etiology and pathogenesis,and to develop relevant novel prevention and treatment procedures.

双氧水脱黑素颗粒优化免疫组织化学染色在眼球恶性黑素瘤诊断中的应用

目的探究采用双氧水去除眼球恶性黑素瘤中黑素颗粒后在免疫组织化学染色中的应用。方法收集本院2018—2021年间收治的眼球恶性黑素瘤病例10例,制作石蜡切片,采用不同浓度(3%和15%)双氧水处理,以及不同的脱黑素颗粒时间(12 h和24 h),然后进行HE染色和免疫组织化学染色检测(melan A、Ki-67、SOX10),分析不同浓度双氧水和不同作用时间对HE染色和免疫组织化学检测指标结果的影响。结果未脱黑素颗粒的HE染色和免疫组织化学染色切片中含有大量黑素颗粒,无法准确进行肿瘤良性或恶性的判读。采用3%双氧水脱黑素颗粒的HE染色和免疫组织化学染色切片中含有部分黑素颗粒,脱色不均且不彻底,细胞形态及组织结构模糊,对结果判读有一定影响。采用15%双氧水和24 h的脱黑素颗粒时间的HE染色和免疫组织化学染色切片中基本无黑素颗粒残留,染色清晰,对肿瘤的良性或恶性能够准确判读。结论高浓度双氧水长时间脱黑素颗粒的效果明显,HE染色和免疫组织化学染色结果的判读清晰且准确。

眼内色素在眼部药物传递中的作用

眼内色素主要存在于葡萄膜（包括虹膜、睫状体、脉络膜）和视网膜色素上皮（RPE）层,它能与很多不同类型的药物结合,如抗生素、麻醉剂、β-受体阻滞剂、糖皮质激素和抗疟药等,结合的关键在于药物的酸碱度和脂溶性.通过研究药物在不同给药途径中的药代动力学和药效学,发现眼内色素与药物的结合在眼部药物传递中起重要的作用.它不仅可以提高药物在组织中的初始浓度,而且色素与大部分药物的结合是可逆的,使得药物可以从色素中缓慢释放而延长药物的作用时间,产生有利或不利的影响.由于不同的药物与色素的结合力不同,且在不同的物种和种族,甚至同一组织的不同区域中眼内色素的含量都有区别,使得药物与色素的结合存在个体差异,因此进一步研究不同药物与眼内色素结合的特点和量化关系,可以为科研和临床用药,特别是经巩膜给药的研究和药物递放系统的开发提供更多的科学依据和指导意义.

药物与眼黑色素结合的体内外研究方法及意义

黑色素是在黑色素小体中合成的一类聚合物。研究显示碱性、亲脂性的芳香族化合物理论上都能够与黑色素发生结合,导致其在含有黑色素的组织中发生积聚,影响药物在体内的药动学和药效学,并可能导致潜在的毒性。然而,在药物递送领域中却也可以利用药物与黑色素的亲和性,增加眼底疾病治疗药物的靶向性。目前常用的药物-黑色素结合能力的研究方法包括体外、体内和计算机预测模型,但尚无基于清楚的结合机制的研究方法。本文对近年来有关药物-黑色素结合能力的体外和体内的研究方法进行详细阐述,并比较了二者的适用性和科学性,以期能够为眼科药物非临床研究提供有效的参考。