SHH基因在高度近视患者中的突变研究

目的 研究定位于7q36的SHH基因突变与高度近视发病的关系。方法 收集高度近视先证者178例，制备外周血白细胞基因组DNA，PCR扩增SHH基因3个外显子及其邻近内含子，SSCP-异源双链法分析PCR产物，寻找可能的变异。结果 分析178例高度近视先证者SHH基因全部3个外显子及邻近内含子，未发现任何变异。结论 SHH基因突变可能与本组高度近视无关。SHH与近视及眼球生长发育的关系尚有待进一步研究。     

病理性近视与LAMA1基因相关性的研究

目的:探讨病理性近视与LAMA1基因之间的相关性。方法:收集汉族病理性近视患者及正常人外周静脉血,提取全基因组DNA,采用聚合酶链反应-单链构象多态性方法,对标本中LAMA1基因第27外显子、第36外显子的基因序列进行扩增及直接测序分析,应用SHEsis软件检验两组样本是否符合哈迪-温伯格平衡(Hardy Weinberg Equilibrium,HWE),通过Fisher确切概率检验病理性近视与LAMA1基因的相关性。结果:本研究中LAMA1基因第27外显子、第36外显子未发现有意义的突变。结论:LAMAl是否可被确认为病理性近视的致病基因尚需更深入的探究。     

中国北方先天性白内障家系中缝隙连接蛋白基因突变的筛查

目的：在一中国人先天性白内障家系中进行缝隙连接蛋白基因（GJA3、GJA8）突变筛查.方法：通过聚合酶链反应（polymerase chain reaction,PCR）对一先天性白内障家系中的全部患者进行GJA3基因及GJA8基因外显子的扩增,扩增产物进行直接测序.结果：该家系GJA8基因的外显子及其邻近的内含子未发现任何突变.先证者GJA3基因外显子非编码区发现碱基CA的缺失.结论：缝隙连接蛋白基因为该先天性白内障家系的非致病性基因.     

排除视网膜特异性表达簇样蛋白1基因变异与中国高度近视人群的相关性

目的 筛查视网膜特异性表达簇样蛋白1(clusterin—1ike proteinl，CLULl)基因编码区域变异与中国高度近视人群的相关性。方法 采用PCR—SSCP检测204例中国人高度近视先证者CLULl基因所有编码外显子及两侧序列有无突变；对有突变的外显子区域进行克隆测序。结果 仅发现1例患者在CLULl基因外显子2的密码子10第3个核苷酸GT G→GT T杂合同义突变，没有氨基酸的改变(Vall0Val)。CLULl基因其余外显子无突变和多态现象。结论 初步排除位于18p11．3D18S63--D18S52 0．8cM范围内视网膜特异表达的CLULl基因与中国高度近视人群的相关性；CLULl基因在中国人群中突变罕见。     

先天性白内障一家系缝隙连接蛋白突变基因筛查

目的对一个先天性白内障家系进行缝隙连接蛋白致病基因的初步筛查。方法通过聚合酶链反应（PCR）对一先天性白内障家系中的全部患者进行GJA8、GJA3候选基因的外显子及内含子扩增,扩增产物进行直接测序,测序结果与GeneBank中原始序列进行BLAST比对分析。结果该家系的2个缝隙连接蛋白候选基因的外显子及其邻近的内含子未发现任何突变。结论GJA8、GJA3为该先天性白内障家系的非致病基因。     

高度近视儿童中未检测到TIGR基因突变

目的:在具有家族史的高度近视儿童中进行TIGR基因突变筛查。方法:对高度近视儿童中TIGR基因第三外显子进行毛细血管电泳测序检测,并对结果进行序列分析。结果:在近视组和对照组中均未发现TIGR基因突变。结论:未能发现TIGR基因突变与高度近视相关证据。     

视网膜色素变性患者特异性光感受器细胞核受体基因突变检测分析

目的 观察特异性光感受器细胞核受体(NR2E3)基因在宁夏地区视网膜色素变性(RP)患者中的突变频率及特征,探讨其在RP发病机制中的作用。方法 经检查确诊的120例RP患者纳入研究。其中,常染色体显性遗传RP (ADRP)患者33例,来自18个家系;常染色体隐性遗传RP (ARRP)患者20例,来自15个家系;散发型RP(SRP)患者67例。选取100名健康成年人作为对照组。采用聚合酶链反应(PCR)和直接测序方法,检测NR2E3基因全编码区和邻近剪切位点的内含子区域序列突变。多因素分析研究NR2E3基因突变位点对RP的作用。结果 120例RP患者NR2E3基因检测出变异位点12个。其中,非编码区5个;第4、6、7外显子上7个。12个变异位点中,新发现变异位点6个。外显子上7个变异位点中,同义突变3个;错义突变4个。统计学分析结果显示,所有变异位点均为NR2E3基因多态性。多因素Logistic回归分析显示,变异位点均与RP发生无相关性。18例ADRP先证者、67例SRP患者和正常对照组中,分别有1、3、2例NR2E3基因第4外显子上发现p.Glu121Lys变异。发生该位点变异的ADRP患者家系（NXRP-1）另外8例患者中,出现p.Glu121Lys位点变异5例,未出现变异3例。出现变异的6例患者发病年龄较未出现p.Glu121Lys位点变异的3例患者早,且较早出现明显的中心视力损害。结论 宁夏地区RP患者NR2E3基因致病突变率小于1％,NR2E3基因的p.Glu121Lys变异发生率较低。     

喉鳞癌PTEN基因第5、8外显子的测序分析

目的探讨PTEN基因与喉鳞状细胞癌的关系.方法应用聚合酶链反应-单链构像多态性分析(polymerase chain reaction-single-strand conformation polymorphism,PCR-SSCP)和TA克隆PCR产物DNA测序技术,检测喉鳞状细胞癌新鲜或冰冻组织中抑癌基因PTEN第5、8外显子的突变情况.结果60例喉鳞状细胞癌组织中使用SSCP检测发现7例显示电泳迁移率的改变.对这7例阳性样本的PCR产物进行TA克隆后测序,2例第5外显子第474位碱基发生A→T的颠换.2例第5外显子第397、407位碱基发生G→A的转换,导致错义突变;1例第5外显子第405位碱基发生A→T的颠换.1例第8外显子第830位碱基发生C→T的转换,导致错义突变;1例第8外显子第831位碱基发生A→C颠换.结论PTEN基因的外显子5突变可能与喉癌的发生有一定的关系,其机制有待深入研究.     

X-连锁隐性遗传高度近视家系的ZNF185基因序列分析

目的：应用基因测序的方法,对一个致病基因已定位于MYP1位点的X-连锁隐性遗传高度近视家系进行基因筛查,探索ZNF185基因与该家系的相关性。方法收集家系中28人临床资料并采集10例患者及18例家系正常成员的外周血,提取基因组DNA,采用PCR扩增ZNF185基因的全部22个外显子及外显子与内含子交界区域,用直接双向测序、BLAST比对进行突变分析。结果对ZNF185基因直接测序发现了4个变异序列（3947C〉T、6054G〉A、7566T〉C、17462delcccactgttcc）均属于基因非编码区SNP（rs733359、rs2071258、rs2071259、rs66958885）,所有变异序列均存在于患者及其部分正常亲属中,与疾病表型无共分离现象。结论排除了ZNF185基因外显子突变导致该家系高度近视的可能性。     

Follow-up studies in pattern VECP in demyelinating diseases in children

Spectral sensitivity functions and the transient decrease of sensitivity to short wavelengths after the offset of yellow light (transient tritanopia) were measured by increment threshold techniques in patients suffering from hereditary macular degenerations. Color vision defects were determined by arrangement tests and the anomaloscope. Central areolar choroidal dystrophy was found to produce a mild protan defect and to reduce foveal spectral sensitivity throughout the visible spectrum by a factor of 100; it also abolishes transient tritanopia. Electroretinogram (ERG) was normal, electrooculogram (EOG) subnormal. Stargardt's disease, despite numerous fluorescent macular spots, does not abolish transient tritanopia nor does it reduce spectral sensitivity, although scotopic matches were performed on the Nagel anomaloscope. Only in severe, advanced cases was transient tritanopia reduced and spectral sensitivity found to follow the absorption spectrum of rods. Routine ERGs and EOGs were normal. Vitelliform macular degeneration, despite the ophthalmoscopically pronounced dystrophic macula, produced only very small changes in spectral sensitivity and transient tritanopia, although a widened matching range on the Nagel anomaloscope and electrophysiological abnormalities were found. Apparently damage of the retinal circuit which connects long and short wavelength-sensitive cones, caused by hereditary conditions, is different from that caused by retinotoxic drugs.     

p53 expression in pterygium in two climatic regions in Turkey

Purpose:

To assess accumulation of p53 protein in samples of primary pterygium from people living in two different climatic regions in Turkey.

Materials and Methods:

Group 1 included 101 pterygium specimens from people in Adana located in southern Turkey. Group 2 included 39 pterygium specimens from people in Ankara, located in the middle of Turkey. Climatic conditions throughout the year are sunnier and warmer in Adana than they are in Ankara. The control group (Group 3) included 30 specimens of conjunctiva that had been excised during cataract surgery from 30 patients without pterygium. The pterygial specimens and control conjunctiva were studied by immunohistochemistry using antibodies against p53 protein. Pearson''s chi-square test was used to compare the p53 immunoreactivity.

Results:

The p53 immunoreactivity in Groups 1 and 2 was greater than it was in the control group (P<0.001). There were no differences in p53 immunoreactivity between Groups 1 and 2 (P= 0.060).

Conclusion:

The p53 immunoreactivity was not correlated with ultraviolet irradiation exposure. The p53 immunoreactivity in our pterygium specimens suggests that pterygium could be a result of uncontrolled cell proliferation.     

Changes in Bruch's membrane in experimental hypercholesteremia in rats

PURPOSE: We investigated the effect of high cholesterol diet for the aging changes in Bruch's membrane of rats. METHODS: After feeding a 4% cholesterol diet for 15 weeks to three young rats 3 months old and four aged rats 23 months old, we observed the morphological changes of Bruch's membrane by electron microscopy, and made a comparison with rats fed an ordinary diet. RESULTS: In one young rat fed a high-cholesterol diet, the endothelial basement membrane of the choriocapillaris formed multiple folds separated from the plasma membrane of the endothelium and showed lamellar thickening and crack in some areas. The elastic fiber layer in Bruch's membrane disappeared partly and some new microfibrils appeared. In one aged rat fed a high-cholesterol diet, the endothelial basement membrane of the choriocapillaris showed more lamellar thickening with lumps in some parts. Compared with rats fed an ordinary diet, rats fed a high-cholesterol diet showed thickening of the basement membrane and the changes were more severe. CONCLUSIONS: Our data indicated that high-cholesterol diet might promote age-related changes of Bruch's membrane.     

Trends in Patterns of Anterior Uveitis in a Tertiary Institution in Singapore

Purpose: To report the trends in etiology of patients with anterior uveitis (AU) in Singapore over 6 years.

Methods: A retrospective review of the clinical records of all new patients who presented with anterior uveitis to the uveitis subspecialty clinic from 2005 to 2010 at Tan Tock Seng Hospital, Singapore.

Results: There were 552 new cases of AU. This comprised 59.5% of a total of 928 new patients diagnosed with uveitis from 2005 to 2010. The mean age was 48.0?±?17.2 years. There was a male predominance (62.5%), with a male:female ratio of 1.7:1. The majority were of Chinese ethnicity (69%), followed by Malays (13.2%). Most cases were unilateral (79.5%) and idiopathic (50.4%). Common etiological causes included Fuchs heterochromic iridocyclitis (FHI) (5.6%), ankylosing spondylitis (AS)-related AU (5.1%), herpes simplex virus (HSV) (4.7%), and herpes zoster virus (HZV) (4.5%). There were increasing trends in AS-related AU from 3.2% in 2008 to 6.5% in 2010, and psoriasis-associated AU from 1.7% in 2005 to 4.0% in 2008. There were decreasing trends in the incidence of FHI from 10.6% in 2006 to 4.7% in 2009. No change in incidence of viral etiologies was noted, but cytomegalovirus-related immune-recovery uveitis (IRU) comprised 7.4%. IRU showed an increasing trend from 1.7% in 2005 to 11.9% in 2007, then decreased to 3.3% in 2010. Using the Pearson chi-square test, there was no statistically significant association between ethnicities (Chinese, Malay, Indian) comparing infectious and noninfectious cases (p?=?0.788), idiopathic and nonidiopathic cases (p?=?0.170), or between the various etiologies of uveitis (p?=?0.168).

Conclusions: AU was the predominant form of uveitis seen at our centers. Infectious etiologies (18.5%) are the most common among nonidiopathic cases, with herpes viruses (9.2%) being most prevalent. Despite increased use of polymerase chain reaction (PCR) in the detection of microbial and viral DNA, there was no overall increase in detection of infectious causes for uveitis. The changes in CMV-related immune recovery uveitis from 2005 to 2010 could reflect a change in HIV management in Singapore.     

Orthokeratology practice in children in a university clinic in Hong Kong*

Purposes: The aim of this study was to analyse clinical data of children undergoing orthokeratology (ortho‐k) and to investigate patients’/parents’ perspective on ortho‐k via telephone interviews. Methods: Clinical records of children undergoing ortho‐k from a university optometry clinic were reviewed and the effects of ortho‐k on refraction, vision and cornea were investigated. A telephone interview was conducted to solicit patients’/parents’ perspective of the treatment. Results: One hundred and eight files were reviewed. Median age of the children was nine years (range six to 15); mean (±SD) pre‐treatment refractive sphere was ‐3.56 ± 1.49 D and the median refractive cylinder was ‐0.50 D (range zero to ‐4.25 D). Significant refractive spherical reduction (58 per cent), improvement in unaided vision and corneal topographical changes were noted after only one night of wear. No significant change in astigmatism was found. Corneal staining was the most commonly observed complication with ortho‐k and more than 80 per cent of patients were advised to apply ocular lubricants to loosen the lens before lens removal. Ortho‐k was mainly undertaken for myopic control and about 90 per cent of the respondents reported good/very good unaided vision after ortho‐k and ranked the treatment as satisfactory or very good. Lens binding and ocular discharge were the most frequently reported problems during the treatment. Conclusion: Under close monitoring, overnight ortho‐k is effective and safe for reducing low to moderate myopia and the treatment is well accepted by the children.     

内毒素诱导的大鼠葡萄膜炎的巨噬细胞中Toll样受体4的表达

目的 探讨在内毒素诱导的Wistar大鼠葡萄膜炎中Toll样受体4(TLR4)阳性细胞与虹膜组织中巨噬细胞的动态变化和分布.方法 实验研究.Wistar大鼠50只,用随机数字法随机分为5组,每组10只,分别为正常对照(0 h)组、6 h组、12 h组、24 h组及48 h组.除0 h组外其余各组均足垫部注射霍乱弧菌内毒素200μg,注射后于裂隙灯显微镜下观察双眼前节炎症反应变化.按实验分组于0、6、12、24、48 h处死大鼠.取虹膜一睫状体及脉络膜组织.通过葡萄膜铺片免疫组织化学方法检测TLR4和巨噬细胞的标记CD163的表达.人工计数虹膜中TLR4~+与CD163~+的细胞并计算细胞密度,计算圆形和多形性的CD163~+细胞占所有CD163~+细胞的百分比.进一步采用免疫荧光双标记检测TLR4和CD163共表达的情况.通过单因素方差分析分别对大鼠虹膜内阳性细胞密度以及圆形、多形性CD163~+细胞的百分比进行统计学检验.结果 正常大鼠虹膜睫状体组织不表达TLR4.6 h组有2只大鼠虹膜内可见少量TLR4~+细胞,12～48 h组所有大鼠虹膜内TLR4~+细胞明显增多(F=167.2,P＜0.001),虹膜内TLR4~+细胞密度分别为(506.1±39.5)个/mm~2(12 h组)、(492.3±54.5)个/mm~2(24 h组)及(663.8±150.2)个/mm~2 (48 h组).在注射LPS后12～48 h期间TLR4~+细胞形态无明显变化.0～48 h组大鼠虹膜内均有CD163~+细胞,0 h组圆形和多形性CD163~+细胞百分比为13%,12～48 h组其百分比约为80%,且圆形细胞主要位于虹膜基质层.免疫荧光双标记可见TLR4和CD163的共表达,TLR4位于细胞膜,CD163位于细胞质.5组大鼠脉络膜内均未见TLR4表达.结论 内毒素诱导的大鼠葡萄膜炎中虹膜内TLR4表达增高,部分虹膜固有巨噬细胞表达TLR4.TLR4可能在葡萄膜炎的发生发展中起一定作用.     

弱视眼底光学相干断层扫描的研究进展

弱视是由于视觉发育关键期内各种异常的视觉经验导致单眼或双眼最佳矫正远视力低于正常同龄儿童,而眼部无明显器质性病变。目前普遍观点认为,弱视的发病机理主要源于视皮层。近年来,光学相干断层扫描（OCT）作为一种先进的活体成像技术,促进了对视网膜形态结构的大量研究,同时也被应用到弱视的研究领域。陆续有不同的研究人员利用OCT发现弱视患者眼底视网膜、脉络膜等眼部结构存在改变。笔者将对弱视眼底OCT的研究进展做一综述。     

实验性糖尿病视网膜微血管病变的病理研究

目的：观察糖尿病视网膜病变（diabetic retinopathy,DR）的组织学改变。方法：应用光镜、免疫组织化学、电镜及组织化学电镜等技术,研究在不同时间点Spregue-Dawley(SD)大鼠视网膜毛细血管基底膜中的Ⅳ型胶原蛋白及层黏蛋白和视网膜毛细胞血管基底膜的厚度,以及其负电荷位点数目的变化。结果：随着糖尿病病程的发展,视网膜毛细血管基底膜下不断增厚伴有Ⅳ型胶原蛋白及层黏蛋白的增加,同时负电荷位点数目减少。结论：视网膜毛细血管基底膜增厚,Ⅳ型胶原蛋白及层黏蛋白的增加,负电荷位点数目减少可能是导致DR渗出性病变的病理基础。