中国人视网膜色素变性1基因突变频率及其与视网膜色素变性的关联分析

目的 研究常染色体显性遗传视网膜色素变性(ADRP)患者和散发视网膜色素变性（RP）患者RP1基因突变频率及特征，并探讨它们在RP发病机制中潜在的作用。 方法 运用聚合酶链反应和直接测序方法，对7个ADRP家系的55例成员、散发RP患者30例及75名健康成年人进行了RP1基因全编码区和邻近剪切位点的内含子区域序列突变的检测。运用单因素分析、多因素Logistic回归分析研究RP1基因突变位点对RP的作用。 结果 ADRP家系成员和散发的RP患者在RP1基因的第四外显子上均检测出852、872、921和939共4个变异位点。在ADRP家系和散发的RP患者中RP1基因的R872H位点改变与RP之间存在显著相关性(χ²=4.469，P=0.03)。P903L位点的改变仅在家系成员中检出，散发病例及正常人中均未检测出。 结论 RP1基因R872H位点多态性可增高RP的危险性，具有潜在的致病性，考虑为家系和散发RP患者的易感基因。P903L位点改变是否为致病基因有待于进一步证实。     

EGF-PE4O重组毒素对喉鳞癌细胞株Hep-2的毒性作用

观察EGF－PE40重组毒素对喉鳞癌细胞的毒性作用,为寻找新型的治疗头颈鳞癌的生物制剂奠定基础。应用MTT比色法测定EGF－PE40重组毒素的生物学活性。并在光镜下观察Hep－2细胞形态变化。确定MTT比色法中Hep－2细胞浓度为2×104／well。选择10％SDS－0．01mol／LHCI作为MTT结晶的溶解液,当EGF－PE40重组毒素为0．53ng／ml时,50％的Hep－2细胞死亡,在一定范围内,随重组毒素增加,细胞损伤加重。     

PCR-GeneScan法检测遗传性聋相关基因GJB2 235 delC和mtDNA A1555G突变

目的:检测GJB2 235delC杂合突变和mtDNA A1555G突变。方法:对120例样本进行诊断试验,其中测序GJB2 235delC杂合突变样本16例,mtDNA A1555G突变17例。用PCR方法对目标片段进行扩增,PCR产物在3100DNA sequencer(ABI)上聚丙烯酰胺胶毛细管电泳,GeneScan、GeneMarker软件数据分析。结果:120例样本均得到检测结果,检出GJB2 235delC杂合突变样本17例,mtDNA A1555G突变17例,1例正常样本误诊为235delC杂合突变而出现假阳性。结论:PCR-GeneScan技术可以同时检测2种不同基因的突变,单管多重PCR和GeneScan荧光标记法结合是同时检测多种突变一种新的思路,而且可能是一种有效的方法。     

X- 连锁迟发性脊椎骨骺发育不良一家系TRAPPC2 基因变异分析

目的分析由TRAPPC2基因变异致X连锁迟发性脊椎骨骺发育不良(SEDT-XL)的临床及基因变异特点。方法回顾分析1个SEDT-XL家系的临床资料及基因检测结果。结果先证者,9岁2个月,因生长缓慢就诊,语言、运动及智力发育正常。身高115 cm(-3SD),臂间距109 cm,上部量56 cm,下部量59 cm,体质量21 kg,招风耳,尖下颌,牙列不齐,颈短,脊柱侧弯,心肺腹未见异常。采集先证者及其父母和舅舅的外周血行全外显子测序,结果显示先证者TRAPPC2基因4号外显子区域存在1个半合子变异c.115delC,导致氨基酸改变p.Q39Sfs*3。该半合子变异来自其母亲,其舅舅存在相同的半合子变异位点。结论 TRAPPC2基因4号外显子区域c.115delC突变为该家系SEDT-XL的致病原因。     

Substandard application of preimplantation genetic screening may interfere with its clinical success

The intent of this study was to evaluate a recent randomized clinical trial evaluating the effect of preimplantation genetic screening (PGS) that reports a negative effect on pregnancy outcome. This article reviews appropriate PGS techniques and how they differ from the trial in question. A closer look at the clinical trial in question reveals significant lack of expertise in biopsy, cell fixation, genetic analysis, and patient selection. At most, this trial demonstrates that in inexperienced hands, PGS can be detrimental. No other conclusions concerning the effect of PGS on pregnancy results can be drawn from the trial.     

DRESS syndrome: a detailed insight

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a serious and potentially fatal adverse effect to therapeutic medications. The incidence of this condition varies among different ethnicities because of the difference in the genetic makeup. Though fever, rash and eosinophilia are essential features for the diagnosis of this syndrome, these vary from patient to patient along with the involvement of various organs such as liver, kidney, lungs, pancreas, etc. Some of the atypical features are dysphagia, agranulocytosis, and chylous ascites. Phenytoin, phenobarbitone, carbamazepine, and allopurinol are the most common drugs responsible for developing this syndrome, although the list is fairly long. Among the criteria used for the diagnosis of DRESS syndrome, European Registry of Severe Cutaneous Adverse Reactions to Drugs and Collection of Biological Samples (RegiSCAR) criteria is the most commonly used one. The management of this syndrome involves early removal of the causative agent and treatment with anti-histamines and emollients in the mild form, corticosteroids in the moderate form and plasmapheresis in the severe form along with other alternatives drugs. Healthcare professionals should be more vigilant about the early manifestations of this syndrome, as early diagnosis and treatment improve outcomes considerably.