以“阴阳理论”为指导治疗视网膜色素变性

视网膜色素变性是一组以进行性感光细胞及色素上皮功能丧失为共同表现的遗传性疾病,治疗极为棘手。唐由之研究员在古代文献的基础上结合现代眼科检查后发现,无论该病患者的自觉症状还是眼底表现,均符合"阴"的特性。如果能从阴阳属性上进行把握,在"阴阳理论"指导下进行辨证论治,则能收到事半功倍的效果。     

视网膜色素变性差异性临床表现及影像学特征

RU视网膜色素变性(RP)是常见的遗传性眼底疾病,典型RP的临床表现为夜盲、视盘蜡黄、骨样细胞色素沉着。现阶段随着RP基因探索的兴起及眼底影像技术的发展,相关研究发现许多RP患者并不完全表现为典型的症状与体征,不同类型的RP患者所合并非典型临床表现及影像学表现也不尽相同,部分患者还可表现为黄斑功能异常、视网膜异常反光等。现对RP的相关临床表现差异性及影像学特征作一综述。     

视网膜变性小鼠视网膜组织中FasL蛋白表达的动态变化

背景 视网膜移植是治疗视网膜变性性疾病的新方法,但如何避免或减少视网膜移植后的免疫排斥反应是亟待解决的问题之一.目前的实验研究中常将正常C57 BL/6小鼠视网膜作为供体,视网膜变性(rd)小鼠作为受体.研究表明视网膜中Fas配体(FasL)蛋白通过FasL/Fas途径诱导Fas+炎症细胞凋亡,推测可能与视网膜移植后的免疫排斥反应密切相关. 目的 探讨FasL蛋白在不同鼠龄C57BL/6小鼠和rd小鼠视网膜中的表达特点,揭示小鼠视网膜的免疫特性,为视网膜移植免疫排斥反应的研究提供参考依据.方法 分别将出生后(PN)-0周(出生日)、PN-1周、PN-2周、PN-3周、PN-4周的正常C57BL/6小鼠和rd小鼠处死制备眼球冰冻切片,采用免疫荧光技术摄片,并经激光扫描共焦显微镜采集图片,用图像分析软件对各鼠龄不同品系小鼠间视网膜中FasL蛋白表达的荧光强度(FI)变化进行半定量分析. 结果 PN-1周C57BL/6小鼠视网膜发育尚不完善,FasL蛋白在视网膜各层均呈阳性表达.PN-2、3、4周C57BL/6小鼠已发育成10层的视网膜结构,FasL蛋白在视网膜色素上皮(RPE)、内节段(IS)、外界膜(OLM)、外丛状层(OPL)、内核层(INL)、内丛状层(IPL)及节细胞层(GCL)呈阳性表达.PN-1周rd小鼠视网膜结构与同龄C57BL/6小鼠接近,FasL蛋白在视网膜各层均呈阳性表达.PN-2周至PN-4周rd小鼠视网膜中外核层(ONL)细胞随着鼠龄增大逐渐减少,FasL蛋白在RPE、OPL、INL、IPL及GCL呈阳性表达;PN-2、3、4周rd小鼠RPE中FasL蛋白表达FI值分别为184.199±16.747、186.797±7.904和184.319±18.795,均明显高于同龄C57BL/6小鼠的160.402±22.851、160.995±22.799和105.787±17.676,差异均有统计学意义(t=-3.360,P=0.002;t’=-4.277,P=O.000;t=-12.175,P=0.000);各周龄rd小鼠与C57BL/6小鼠间视网膜IPL中FasL蛋白表达的FI值差异均无统计学意义(均P＞O.05).结论 rd小鼠随着鼠龄增加视网膜ONL细胞逐渐减少,其RPE内免疫赦免相关抗原FasL蛋白的表达强度明显高于同龄C57BL/6小鼠.     

脑源性神经营养因子治疗视网膜色素变性的研究进展

脑源性神经营养因子(BDNF)是一种由脑组织合成并广泛分布于中枢神经系统的小分子碱性蛋白.研究发现,BDNF对视网膜神经节细胞(RGCs)、视网膜感光细胞(RPCs)和视网膜色素上皮(RPE)细胞均有保护、营养及抗凋亡作用.视网膜色素变性(RP)是由于RPCs及RPE细胞凋亡引起的视网膜退行性疾病.RP动物模型证实了BDNF的长期给药对于RP的治疗价值.然而BDNF在体内的半衰期较短,且无法跨越血-视网膜屏障由循环系统输送到视网膜,这给BDNF用于RP的治疗带来了挑战.为了使BDNF在眼内可以稳定持续地释放,多种新型给药方式已被尝试,包括基因工程技术、细胞移植技术、高分子材料缓释系统及滴眼液等.本文就BDNF对RP治疗的研究现状及BDNF的新型给药方式做一综述.     

Artificial Intelligence–Assisted Early Detection of Retinitis Pigmentosa — the Most Common Inherited Retinal Degeneration

The purpose of this study was to detect the presence of retinitis pigmentosa (RP) based on color fundus photographs using a deep learning model. A total of 1670 color fundus photographs from the Taiwan inherited retinal degeneration project and National Taiwan University Hospital were acquired and preprocessed. The fundus photographs were labeled RP or normal and divided into training and validation datasets (n = 1284) and a test dataset (n = 386). Three transfer learning models based on pre-trained Inception V3, Inception Resnet V2, and Xception deep learning architectures, respectively, were developed to classify the presence of RP on fundus images. The model sensitivity, specificity, and area under the receiver operating characteristic (AUROC) curve were compared. The results from the best transfer learning model were compared with the reading results of two general ophthalmologists, one retinal specialist, and one specialist in retina and inherited retinal degenerations. A total of 935 RP and 324 normal images were used to train the models. The test dataset consisted of 193 RP and 193 normal images. Among the three transfer learning models evaluated, the Xception model had the best performance, achieving an AUROC of 96.74%. Gradient-weighted class activation mapping indicated that the contrast between the periphery and the macula on fundus photographs was an important feature in detecting RP. False-positive results were mostly obtained in cases of high myopia with highly tessellated retina, and false-negative results were mostly obtained in cases of unclear media, such as cataract, that led to a decrease in the contrast between the peripheral retina and the macula. Our model demonstrated the highest accuracy of 96.00%, which was comparable with the average results of 81.50%, of the other four ophthalmologists. Moreover, the accuracy was obtained at the same level of sensitivity (95.71%), as compared to an inherited retinal disease specialist. RP is an important disease, but its early and precise diagnosis is challenging. We developed and evaluated a transfer-learning-based model to detect RP from color fundus photographs. The results of this study validate the utility of deep learning in automating the identification of RP from fundus photographs.     

色素性痒疹2例

报告2例色素性痒疹。例1女,17岁。躯干出现皮疹伴瘙痒3月。例2男,23岁。胸背部出现皮疹伴瘙痒5年余。该2例患者皮损均表现为胸背部片状或网状红斑、丘疹及斑丘疹,瘙痒剧烈,皮疹反复发生,愈后遗留有明显的褐色网状色素沉着斑,皮损组织病理示色素性痒疹,用美满霉素治疗效果良好。     

Mutation profile of the CDH23 gene in 56 probands with Usher syndrome type I

Mutations in the human gene encoding cadherin23 (CDH23) cause Usher syndrome type 1D (USH1D) and nonsyndromic hearing loss. Individuals with Usher syndrome type I have profound congenital deafness, vestibular areflexia and usually begin to exhibit signs of RP in early adolescence. In the present study, we carried out the mutation analysis in all 69 exons of the CDH23 gene in 56 Usher type 1 probands already screened for mutations in MYO7A. A total of 18 of 56 subjects (32.1%) were observed to have one or two CDH23 variants that are presumed to be pathologic. Twenty one different pathologic genome variants were observed of which 15 were novel. Out of a total of 112 alleles, 31 (27.7%) were considered pathologic. Based on our results it is estimated that about 20% of patients with Usher syndrome type I have CDH23 mutations.     

Toxoplasma gondii: an atypical presentation of toxoplasma as optic disc swelling and hemispherical retinal vein occlusion treated with intravitreal clindamycin

Background To present a case of toxoplasmosis with an atypical presentation and treated successfully with intravitreal clindamycin. Method A young Brazilian woman presented with panuveitis and disc swelling with associated hemispheric vascular occlusion in one eye. The presumed diagnosis was of a papillitis with vasculitis due to an unknown inflammatory condition. Results Following treatment with intravenous corticosteroids, macular star appeared 1 week after treatment. On the 2nd week, a focus of retinitis appeared, and the patient was started on antitoxoplasma treatment. This was poorly tolerated, and the patient was injected with intravitreal clindamycin. Inflammation eventually settled and an organized lesion typical of toxoplasma chorioretinitis was observed. Conclusion We describe an unusual presentation and the detrimental effects of toxoplasmosis in an otherwise immunocompetent subject. As the patient was not tolerating systemic antitoxoplasma treatment, intravitreal injection was administered and proved to be effective and well tolerated.     

在体电穿孔辅助基因转染视网膜色素上皮细胞层和光感受器细胞层的实验研究

目的　探讨在体电穿孔辅助基因转染视网膜色素上皮（RPE）细胞层和光感受器（PR）细胞层的可行性。方法　147只健康雄性Spragne-Dawley(SD)大鼠根据电穿孔刺激模式电压值分为5、10、15、20、25、30、35 V组,右眼视网膜下腔注射增强型绿色荧光蛋白（EGFP）真核表达质粒pEGFP N1为实验眼,左眼注射TE Buffer 为对照眼。各组根据不同转染方向再分为RPE和PR两个亚组。各组除电压不同外,其余参数均为脉宽99 ms,脉冲间期0.5 s,连续5个脉冲。将带有负电荷的质粒在电场作用下,拟转染到RPE细胞层,反向置电极,拟转染到PR细胞层。转染后7 d 取各组视网膜铺片,荧光显微镜下观察EGFP表达强弱、范围及荧光细胞计数分析;采用蛋白质免疫印迹法（Western blot）、实时逆转录聚合酶链反应（RT-PCR）半定量观察EGFP蛋白和mRNA的表达。结果　转染后7 d,荧光显微镜观察发现,各组RPE亚组对照眼RPE细胞层内均未见特异性荧光表达,实验眼可见绿色荧光表达;各组RPE亚组对照眼视网膜铺片均未见荧光表达,实验眼视网膜铺片均可见转染了EGFP的RPE细胞。Western blot检测显示,随电压增加,EGFP蛋白与β-肌动蛋白条带灰度相对比值呈上升趋势。RT-PCR检测显示,各组均产生阳性扩增条带,随电压增高,EGFP mRNA与GADPH mRNA扩增条带灰度相对比值逐渐增高。结论　在体电穿孔方法可以有效辅助基因转染大鼠RPE细胞层。      

细胞因子信号传导抑制因子在实验性自身免疫性葡萄膜视网膜炎视网膜内的表达

目的 探讨细胞因子信号传导抑制因子(SOCS)在实验性自身免疫性葡萄膜视网膜炎(EAU)视网膜内的表达与意义.方法 随机对照实验设计方法.90只Lewis大鼠采用分层随机抽样进行分组,分别为未治疗组40只大鼠、治疗组40只大鼠及正常对照组10只大鼠.用光感受器间维生素A类结合蛋白(IRBP)诱导EAU动物模型,治疗组从免疫后1～28 d,给予环孢素(CsA)灌胃,每天20 mg/kg体重,而未治疗组给予等量生理盐水,正常对照组未给予免疫和治疗.分别于免疫后7、14、21、28 d按分层随机号抽取治疗组与未治疗组各10只大鼠进行相关枪测,观察大鼠眼部炎性变化,双眼取材,分别用实时荧光定量聚合酶链反应和蛋白免疫印迹法检测大鼠视网膜内SOCS mRNA和蛋白的表达,酶联免疫吸附试验方法检测血清细胞因子白细胞介素4(IL-4)、IL-12、干扰素γ(IFN-γ)的水平.利用单因素方差分析对治疗组与未治疗组大鼠血清中细胞因子的浓度和视网膜内SOCS蛋白表达量进行对比分析,多重比较采用最小显著差异法;用Mann-Whitney两样本比较秩和检验进行治疗组与未治疗组大鼠炎性反应分值比较.结果 免疫后14 d,未治疗组可见明显的虹膜睫状体炎,房水闪辉阳性,虹膜后粘连,瞳孔不规则甚至前房积脓,炎性反应分值是1.5±0.5;而治疗组眼部炎性反应不明显,炎性反应分值是0.5±0.3.未治疗组的IL-12、IFN-γ及IL-4免疫后14 d达到最高峰(均P＜0.05),免疫后28 d IL-12、IFN-γ下降到正常水平(均P＞0.05),IL-4仍高于正常对照组(P＜0.05);治疗组中IL-12、IFN-γ的动态变化不明显(均P＞0.05),IL-4在整个病程中呈上升趋势(均P＜0.05).SOCS1、含SH2结构的细胞因子诱导蛋白(CIS)mRNA免疫后14 d表达最高,未治疗组分别是正常对照组的3.41倍和3.36倍,治疗组分别为1.44倍和1.73倍;SOCS3和SOCS5mRNA在整个病程中逐渐升高,免疫后28 d表达最高,未治疗组中分别为正常对照组的1.95倍和3.16倍,治疗组中分别为正常对照组的1.59倍和3.58倍.未治疗组SOCS1和CIS蛋白在免疫后7、14、21 d时显著高于正常对照组(均P＜0.05),治疗组二者免疫后14 d显著高于正常对照组(均P＜0.05);两组中SOCS3和SOCS5蛋白在免疫后均显著高于正常对照组(均P＜0.05).结论 EAU发生过程中视网膜SOCS1升高与Th1型反应增强有关;在发病的不同阶段中CIS与SOCS3升高和Th2细胞反应增强以对抗Th1细胞反应,与缓解葡萄膜炎的发病强度有关;SOCS5水平升高在眼局部炎性反应发生过程中可能起保护作用.