温敏性羟丁基几丁糖作为玻璃体填充物的实验研究

发布时间：2018-06-23 15:18

本文选题：玻璃体填充物 + 0.8%温敏性羟丁基几丁糖　；参考：《第二军医大学》2017年硕士论文

【摘要】：研究目的:玻璃体可以支撑视网膜,减缓外力冲击;也可以储存氧气、葡萄糖、抗坏血酸等,支持相邻组织代谢;还可以避免视网膜与眼前段之间的物质扩散;同时玻璃体也是眼内最大的屈光物质,一旦损伤即不可再生。发育异常、组织退变、眼内炎症、眼外伤、眼内出血及全身疾病如糖尿病等均可以导致玻璃体发生病理变化,从而导致患者视力下降甚至失明。玻璃体视网膜疾病可以通过玻璃体切除术获得有效治疗,术后常需要填充合适的材料来维持眼球体积,支撑视网膜。水凝胶由于高含水量,优良的光学透明度和流变性能成为了玻璃体填充物研究热点。本实验通过体外检测温敏性羟丁基几丁糖(hydroxybutyl chitosan,HBC)凝胶的光学性质、物理学性质、成胶时间和急性眼刺激情况,分析温敏性羟丁基几丁糖凝胶进行玻璃体填充的可行性,并将温敏性羟丁基几丁糖填充兔眼玻璃体内,进一步探索其是否适合作为玻璃体填充物。材料和方法:实验一:温敏性羟丁基几丁糖作为玻璃体填充物的基础性能研究温敏性羟丁基几丁糖浓度越高,透明度越差,成胶温度也越低。其中0.8%温敏性羟丁基几丁糖在溶胶及凝胶状态,均为透明形态,并且适合在37℃成胶,符合人体温度,可适用于玻璃体内填充,所以本实验选取0.8%温敏性羟丁基几丁糖作为实验材料。(1)、体外测量0.8%温敏性羟丁基几丁糖凝胶含水率、透光率、屈光指数、比重、酸碱度和存储模量、损耗模量,与自然玻璃体进行比较。(2)反复测量并记录其溶胶转变为凝胶的相变时间。(3)、将0.1ml、0.3ml的0.8%温敏性羟丁基几丁糖分别滴入6只兔眼结膜囊,72小时内通过裂隙灯观察结膜、角膜、虹膜是否有急性炎症刺激反应。实验二:温敏性羟丁基几丁糖填充兔眼玻璃体安全性实验研究36只白兔随机分为三组,右眼为手术操作眼,进行玻璃体切除手术,术后A组白兔填充温敏性羟丁基几丁糖(HBC),B组填充透明质酸钠凝胶,C组填充平衡盐溶液(BSS)。术后1、3、7、14、21、28天分别行裂隙灯、直接检眼镜检查术眼各部位(结膜、角膜、前房、晶状体、玻璃体、眼底)情况,眼压计测量眼压。术后4周、8周、12周分别行眼部B超、眼底照相及视网膜光学相干断层成像等检查,并随机从三组中选取部分实验动物进行眼球摘除,制作病理切片,通过光学显微镜和电子显微镜观察超微结构改变。结果:1、0.8%温敏性羟丁基几丁糖凝胶含水率为98.7%、屈光指数为1.3321、透光率为99.95%、比重为1.008 g/cm3,物理性质及光学性质均接近于自然玻璃体,pH值相较于自然玻璃体(7.0~7.5)稍低,为6.97,不排除操作误差及温度影响。温敏性羟丁基几丁糖凝胶状态下储存能量(弹性)平均值为267.08±0.78 Pa,损耗模量(粘性)平均值为17±1.12Pa,属于弹性材料。温敏性羟丁基几丁糖4℃到37℃相变(溶胶→凝胶)平均用时为59±2s。将0.8%温敏性羟丁基几丁糖滴入实验动物结膜囊内72小时,兔眼穹窿部结膜可见凝胶残余物和少许分泌物,未见结膜充血、角膜损伤、虹膜粘连,兔眼瞳孔对光反射正常。2、玻璃体切除术后,A组(温敏性羟丁基几丁糖组)、B组(透明质酸钠组)、C组(BSS组)三组白兔均出现了暂时性眼内炎症反应,后期发生晶状体混浊,其中A组2例(16.7%),B组3例(25%),C组1例(8.3%)。A组眼压于术后7天与术前比较有差异(P0.05),B组眼压于术后2月时降低,与术前比较有差异(P0.05)。术后眼后节检查可见A组兔眼玻璃体内不透明,呈现灰白色团块状混浊,随时间变化团块逐渐变小,眼底模糊无法窥清。B组玻璃体透明度欠佳,眼底细节隐约可见。C组玻璃体透明,眼底细节清晰可见。组织病理学显示三组兔眼角膜及视网膜超微结构未见明显异常,其中视网膜平伏,结构层次清晰,未发生视网膜脱离及增生,但B组兔眼视网膜神经节细胞层细胞有所减少。结论:1、0.8%温敏性羟丁基几丁糖凝胶的光学性质和物理性质及粘弹性可以模拟自然玻璃体。2、0.8%温敏性羟丁基几丁糖填充兔眼玻璃体显示出良好生物相容性,但是会引起玻璃体的不透明和灰白色团块状混浊,目前尚不是理想的玻璃体替代物。玻璃体内水凝胶药物递送系统通常仅占据玻璃体腔的一小部分,它们并不一定要求眼内呈透明状,温敏性羟丁基几丁糖在玻璃体内药物递送系统中可有进一步研究。
[Abstract]:Objective: the vitreous body can support the retina, slow down the external force impact, and can also store oxygen, glucose, ascorbic acid, support metabolism of adjacent tissues, and avoid the material diffusion between the retina and the anterior segment; and the vitreous body is also the largest diopter in the eye. Once the injury is nonrenewable, abnormal development, tissue degeneration, Intraocular inflammation, ocular trauma, intraocular bleeding, and systemic diseases such as diabetes can cause pathological changes in the vitreous body, which can lead to visual loss and even blindness. Vitreous retinal diseases can be effectively treated by vitrectomy, and the appropriate materials are often needed to maintain the volume of the eyeball and support the retina. The excellent optical transparency and rheological properties of hydrogels have become a hot spot in the study of vitreous padding. In this experiment, the optical properties, physical properties, gelation time and acute eye stimulation of thermosensitive hydroxybutyl chitosan (hydroxybutyl chitosan, HBC) gels were detected in this experiment. The feasibility of filling the vitreous body with the glue and filling the glass body of the rabbit eye with thermosensitive hydroxybutyl chitosan to further explore whether it is suitable as a vitreous filler. Materials and methods: Experiment 1: the temperature sensitive hydroxybutyl chitosan as the base of the vitreous filler, the higher the temperature sensitive hydroxybutyl chitosan concentration, the transparency. The more poor the gelatin temperature is, the 0.8% thermosensitive hydroxybutyl chitosan is transparent in the sol and gel state, and is suitable for filling in the body at 37 degrees centigrade, which is suitable for the body temperature. So 0.8% thermosensitive hydroxybutyl chitosan is selected as the experimental material in this experiment. (1) the measurement of 0.8% thermosensitive hydroxyl butyl in vitro Water content, transmittance, refractive index, diopter index, specific gravity, pH, storage modulus, loss modulus, and natural vitreous modulus were compared with natural vitreous. (2) the phase transition time of the sol changed into gel was measured and recorded repeatedly. (3) 0.1ml, 0.3ml 0.8% thermosensitive hydroxybutyl chitosan was dripped into 6 rabbit eye conjunctiva, and the slit lamp was observed within 72 hours. Experimental two: 36 rabbits were randomly divided into three groups: the right eye was operated in three groups, the right eye was operated in the eye, the vitrectomy was performed, the white rabbits in the A group were filled with thermosensitive hydroxyl chitosan (HBC), and the B group filled with sodium hyaluronate. The gel, C group filled the balance salt solution (BSS). After 1,3,7,14,21,28 days, the eyes were examined by the fissure lamp, and the ophthalmoscope was examined by direct ophthalmoscope (conjunctiva, cornea, anterior chamber, lens, vitreous body, fundus), and intraocular pressure was measured by the intraocular pressure meter. 4 weeks, 8 weeks, and 12 weeks after operation, the eye B ultrasound, fundus photography and retina optical coherence tomography were performed respectively. Some experimental animals were extirpated from the three groups, and the pathological sections were made. The ultrastructural changes were observed by optical microscope and electron microscope. Results: the moisture content of 1,0.8% thermosensitive hydroxyl butyl chitosan gel was 98.7%, the refractive index was 1.3321, the transmittance was 99.95%, the specific gravity was 1.008 g/cm3, and the physical and optical properties were all Close to the natural vitreous body, the pH value is slightly lower than that of the natural vitreous body (7.0~7.5), which is slightly lower than the natural vitreous body (7.0~7.5), and is 6.97. It does not exclude the operating error and temperature. The average value of the storage energy (elasticity) is 267.08 + 0.78 Pa, the average value of the loss modulus (stickiness) is 17 + 1.12Pa, and the temperature sensitive hydroxybutyl chitosan is 4 centigrade. The average use of phase transition (sol-gel) at 37 degrees (sol-gel) was 59 + 2s. to drop 0.8% thermosensitive hydroxybutyl chitosan into the conjunctival sac for 72 hours. The conjunctiva of the rabbit eye dome could see the gel remnants and a few secretions. No conjunctiva congestion, corneal injury, iris adhesion, rabbit eye pupil to light reflex normal.2, vitrectomy, A group (Wen Min) In group B (sodium hyaluronate group), group B (sodium hyaluronate group) and group C (group BSS), there were temporary intraocular inflammatory reactions in group C (group BSS), and late lens opacities occurred in group A, group B (16.7%), group B, 3 (25%), 1 group (8.3%) in group C (P0.05) compared with pre operation (P0.05), and group B decreased in February, compared with pre operation. There was a difference (P0.05). The posterior segment of the eye showed that the vitreous body of the rabbit eyes of group A was opaque and showed a gray and white lump of turbid. The changes of the masses gradually became smaller with time. The blur of the fundus could not be seen in the vitreous body of the group.B, the vitreous body of the.C group was clear and the details of the fundus were clearly visible. The histopathology showed three groups of rabbits' eyes. There were no obvious abnormalities in the ultrastructure of the cornea and retina, of which the retina was flat, the structure was clear, retinal detachment and proliferation did not occur, but the retinal ganglion cell layer cells in the B group were reduced. Conclusion: the optical and physical properties and viscoelasticity of the 1,0.8% thermosensitive hydroxyl butyl chitosan gel can simulate the natural vitreous body. 2,0.8% thermosensitive hydroxyl butyl chitosan has good biocompatibility in vitreous body, but it can cause opaque and gray white turbid in vitreous. It is not an ideal substitute for vitreous body. The glass body hydrogel delivery system usually only occupies a small part of the glass body cavity. They are not necessarily required. The eye is transparent and thermosensitive butyl chitin can be further studied in vitreous drug delivery system.
【学位授予单位】：第二军医大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R779.6

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