以羊膜为底物培养鸡角膜缘上皮细胞的实验研究

目的为眼表面重建术提供良好的移植材料。方法用胰酶及EDTA消化法去除羊膜上皮将消化、离心获得的鸡角膜缘上皮细胞调成1×107/mlDMEM悬液,接种在6孔培养板底的羊膜基底膜面,放人37℃,5％CO2孵箱培养。结果48h羊膜上培养细胞形成单层,较培养板上培养的同种细胞小,细胞表面的微绒毛及侧面足状突丰富,立体感明显。结论以羊膜基底膜为底物培养的鸡角膜缘上皮细胞可以着床生长并形成完整的单层上皮,为眼表重建使用羊膜及基底膜面培养的角膜上皮细胞提供了实验材料。同时表明羊膜在体外也可以促进鸡角膜缘上皮细胞生长。     

不同移植手术治疗角膜缘干细胞缺损的实验研究

目的探讨以人羊膜为载体培养的角膜缘干细胞，自体及异体移植治疗全角膜缘干细胞缺损。方法制作兔眼角膜缘干细胞完全缺损3个月的模型。实验动物随机分为自体移植组和异体移植组，前者取对侧眼角膜缘组织，后者取异体兔眼角膜缘组织，均以去除上皮细胞的羊膜基底膜为载体，培养12d后行角膜缘干细胞羊膜移植术。术后观察3个月，以角膜上皮染色、角膜浑浊和新生血管3项指标进行临床疗效评定，通过病理检查评估术后角膜上皮修复情况，印迹细胞学检查移植前后角膜上皮的细胞表型。结果体外培养的兔角膜缘干细胞可在羊膜上粘附生长并增生，体外培养12d可形成复层。自体移植组和部分异体移植组术后角膜上皮逐渐愈合，透明度提高，基质细胞浸润减轻，新生血管减退或消失。印迹细胞学检查显示：移植前角膜上皮细胞PAS阳性，而移植后转为阴性；组织病理学显示：移植前角膜上皮大部分缺损，移植后呈现角膜上皮结构。部分异体移植组术后出现了免疫排斥反应。结论兔自体角膜缘干细胞羊膜移植术可重建眼表；免疫排斥反应仍是异体角膜缘干细胞羊膜移植术失败的主要原因。     

兔舌黏膜细胞构建组织工程化角膜上皮的实验研究

目的探讨兔舌黏膜上皮细胞以去上皮羊膜为载体,体外构建组织工程角膜上皮的可行性和方法,试图为眼表重建寻求另一种来源丰富的有效组织工程化角膜移植材料。方法胰酶消化去除羊膜上皮细胞,保留基底膜作为载体,将兔舌黏膜上皮细胞种植于去上皮羊膜基底膜进行体外培养扩增。对培养获得的复合上皮片进行形态观察、常规病理切片HE染色和透射电镜观察。采用AE1/AE3单克隆抗体鉴定复合上皮片中有无角蛋白表达。结果兔舌黏膜上皮细胞在去上皮羊膜基底膜面能黏附生长并增殖,体外培养2～3周左右即可在羊膜上汇合成片并分层。形成的复合上皮片由羊膜基底膜和2～3层较扁平的上皮细胞组成,细胞之间可见桥粒连接,细胞表达角蛋白。结论兔舌黏膜上皮细胞以去上皮羊膜为载体,经体外培养扩增获得的复层组织,初具角膜上皮的雏形结构。     

组织工程技术眼表重建的研究概况

严重的眼表疾病的治疗一直是眼科临床上的难题，组织工程技术的兴起为眼表重建带来了希望。角膜缘干细胞作为角膜上皮组织更新和再生的源泉，在体外选择近似生理条件下培养可生长增殖，获取足量种子细胞；选择促进角膜上皮细胞生长并具有良好组织相容性的载体来种植种子细胞，从而体外构建成复合角膜上皮移植片重建眼表，目前在动物实验及临床应用上都获得了良好的效果，组织工程化角膜上皮为眼表重提供了较理想的方法，存在着许多优势，但目前属于初步研究阶段，仍面临着许多困难和挑战，有待进一步研究。     

以羊膜为载体培养角膜内皮细胞的实验研究

目的 以羊膜为载体培养角膜内皮细胞并形成单层组织，为以后内皮细胞层移植提供方法和材料来源。方法 胰酶消化去除羊膜上皮细胞，保留其底膜作为载体，种植兔角膜内皮细胞，体外培养形成单层内皮层，并进行形态，组织学，超微结构观察。结果 角膜内皮细胞在羊膜上黏附生长并增殖，体外培养6-7d即融合成单层，其形态及生长密度优于单纯培养皿上培养的内皮细胞。复合角膜内皮组织由羊膜基底膜和单层扁平内皮细胞组成，与生理状态下的角膜内皮组织相近。结论 以羊膜为载体培养角膜内皮细胞可形成单层细胞层，有望成为角膜内皮移植良好的材料来源。     

体外重建角膜上皮组织的实验研究

利用体外培养重建同基因角膜上皮组织的新方法，为角膜化学伤后重建角膜表面提供理想的角膜上皮移植片。方法以同种或异种脱水保存的浅层角膜基质片作为载体，通过体外培养自体缘上皮细胞，并使其在体外形成复层角膜上皮组织。     

羊膜为载体的人角膜缘上皮细胞移植治疗大鼠角膜碱烧伤的研究

目的研究人角膜缘上皮细胞的生物学特性,探讨体外培养的人角膜缘上皮细胞移植进行眼表重建的临床应用价值及前景。方法体外培养人角膜缘上皮细胞,通过免疫荧光染色法和逆转录聚合酶链反应（RT．PCR）法分析表型,Brdu掺入法检测慢周期（slow—cycling）细胞。建立大鼠角膜碱烧伤模型,随机分为单纯对照组、羊膜移植（AMT）组及羊膜为载体的角膜缘上皮细胞移植（LSAT）组,术后通过裂隙灯显微镜观察、角膜切片HE染色及免疫荧光染色等方法对各组大鼠眼表恢复情况进行评价。结果培养早期大多数角膜缘上皮细胞p63和K19染色阳性,仅少数细胞K3染色阳性;随培养时间的延长,K3阳性细胞增多,部分细胞同时表达p63和K3。RT—PCR示培养的角膜缘上皮细胞中p63和K12均有阳性表达,而角膜上皮细胞仅表达K12。Brdu掺入法检测到慢周期细胞。动物实验表明,LSAT可以显著减轻角膜病变,使角膜恢复完整性和透明性,眼表评分各项指标与AMT组和对照组比较差异均有统计学意义。LSAT组大鼠角膜切片染色示大部分上皮细胞抗人核和K3染色阳性。结论体外培养的人角膜缘上皮细胞中p63不仅表达于角膜缘干细胞,在短暂扩充细胞中也有一定量的表达;慢周期细胞的存在证实了培养的角膜缘上皮细胞中角膜缘干细胞的存在,p63和K19阳性、K3阴性的细胞为角膜缘干细胞;羊膜为载体的体外培养的人角膜缘上皮细胞移植可有效重建眼表,具有较高的临床应用价值与发展前景。     

不同诱导剂对体外角膜缘干细胞培养的影响

眼表重建常用的羊膜移植或自体角膜缘干细胞移植的方法,对眼表组织损伤过大,且对眼表自身干细胞缺乏者临床效果较差。我们常采用体外培养自体角膜缘干细胞后联合生物载体进行眼表移植重建。本实验对兔角膜缘干细胞进行体外培养,观察不同的诱导环境对于细胞最终的繁殖分化的影响。     

口腔黏膜上皮培养与眼表移植的研究进展

人角膜上皮细胞由角膜缘干细胞不断补充, 从而维持眼表稳态及正常视觉功能。热化学烧伤、Stevens-Johnson综合征等眼表损伤或疾病可导致角膜缘干细胞缺损, 严重影响患者视力。当双眼角膜缘干细胞缺损时可考虑非角膜缘性自体上皮组织移植。口腔黏膜上皮细胞是眼表重建的重要种子细胞来源, 体外培养构建的细胞片已在临床应用中取得良好效果。本文围绕载体、培养条件及技术等影响口腔黏膜上皮片培养的各种因素, 以及细胞片应用于临床眼表移植的优缺点, 对利用口腔黏膜上皮治疗角膜缘干细胞缺损的研究进展进行综述, 以期为安全有效地重建眼表上皮提供研究方向。     

培养角膜上皮移植的实验研究

为尝试体外培养角膜上皮组织移植的方法,以治疗角膜表层疾患,我们以脱水保存的同种或异种浅层角膜基质片作为载体,通过体外培养同基因角膜缘上皮细胞,使其在体外形成近乎生理状态下的角膜上皮组织,再将其移植于损伤的角膜上。实验结果证实体外培养的角膜上皮组织与生理状态下的角膜上皮组织相近,动物移植透明愈合,并且未出现明显的移植排斥反应。     

Strabisme Alternant - Etude clinique - traitement

The author defines motor and sensory alternation: the term alternation should not be used in isolation, it should always be accompanied by the name of the parameter concerned. Sensory alternation is always found together with motor alternation but the reverse is not true.The examining criteria for a diagnosis of sensory alternation are given, sensory alternation must not be confused with alternating inhibition. Working from clinical observations of cases of motor alternating strabismus, the author selects 2 types of binocular sensory relations which allow one to differentiate between:- cases of primary alternating strabismus- cases of secondary alternating strabismusThese forms will develop in different ways; in both cases a cure is possible providing that the right treatment is prescribed and once prescribed carefully followed, etc. It is always a case of serious forms of strabismus whose developmental period is spread over several years.According to the authors, the frequency of cases of true primary strabismus is from 1–3%, the frequency of cases of secondary alternating strabismus varies according to the type of therapy practised on cases of monocular strabismus with amblyopia. These latter will become cases of alternating strabismus under the influence of certain types of therapy carried out over several years (penalization, rocking, alternated occlusion, etc...).Experimental data on kittens confirm clinical data; kittens placed in abnormal environments during the sensitive period will show modification in the distribution of cortical cells and the absence of binocular cells (either because the excitation of the two eyes was not simultaneous, or not identical: artificial strabismus, occlusion, opaque glasses). This disturbances become irreversible after a certain period of exposure (a function of age, length of exposure, etc...).It is thus necessary to bear in mind: 1) the iatrogenic risks of certain orthoptic treatments, 2) the necessity for a binocular form of treatment as soon as possible, as once a certain stage is passed, cortical plasticity diminishes and the elaboration of normal binocular relations becomes impossible.

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Effects of Adenosine Agonists on Intraocular Pressure and Aqueous Humor Dynamics in Cynomolgus Monkeys

The effects of single or multiple topical doses of the relatively selective A₁adenosine receptor agonists (R)-phenylisopropyladenosine (R-PIA) and N⁶-cyclohexyladenosine (CHA) on intraocular pressure (IOP), aqueous humor flow (AHF) and outflow facility were investigated in ocular normotensive cynomolgus monkeys. IOP and AHF were determined, under ketamine anesthesia, by Goldmann applanation tonometry and fluorophotometry, respectively. Total outflow facility was determined by anterior chamber perfusion under pentobarbital anesthesia. A single unilateral topical application of R-PIA (20–250 μg) or CHA (20–500 μg) produced ocular hypertension (maximum rise=4.9 or 3.5 mmHg) within 30 min, followed by ocular hypotension (maximum fall=2.1 or 3.6 mmHg) from 2–6 hr. The relatively selective adenosine A₂antagonist 3,7-dimethyl-1-propargylxanthine (DMPX, 320 μg) inhibited the early hypertension, without influencing the hypotension. Neither 100 μg R-PIA nor 500 μg CHA clearly altered AHF. Total outflow facility was increased by 71% 3 hr after 100 μg R-PIA. In conclusion, the early ocular hypertension produced by topical adenosine agonists in cynomolgus monkeys is associated with the activation of adenosine A₂receptors, while the subsequent hypotension appears to be mediated by adenosine A₁receptors and results primarily from increased outflow facility.