应用全血直接PCR酶切法快速诊断儿童脊肌萎缩症

2003年5月-2004年11月,我们采用改进的无须DNA抽提的全血直接PCR-酶切法,成功地建立了一种更为简单、快速、准确的进行性脊髓性肌肉萎缩症(简称脊肌萎缩症,SMA)分子诊断方法,并将其应用于临床.报道如下.

Objectives: Auditory neuropathy (AN) is a sensorineural hearing disorder characterized by absent or abnormal auditory brainstem responses (ABRs) and normal cochlear outer hair cell function as measured by otoacoustic emissions (OAEs). Many risk factors are thought to be involved in its etiology and pathophysiology. Three Chinese pedigrees with familial AN are presented herein to demonstrate involvement of genetic factors in AN etiology. Methods: Probands of the above - mentioned pedigrees, who had been diagnosed with AN, were evaluated and followed up in the Department of Otolaryngology Head and Neck Surgery, China PLA General Hospital. Their family members were studied and the pedigree diagrams were established. History of illness, physical examination,pure tone audiometry, acoustic reflex, ABRs and transient evoked and distortion- product otoacoustic emissions (TEOAEs and DPOAEs) were obtained from members of these families. DPOAE changes under the influence of contralateral sound stimuli were observed by presenting a set of continuous white noise to the non - recording ear to exam the function of auditory efferent system. Some subjects received vestibular caloric test, computed tomography (CT)scan of the temporal bone and electrocardiography (ECG) to exclude other possible neuropathy disorders. Results: In most affected subjects, hearing loss of various degrees and speech discrimination difficulties started at 10 to16 years of age. Their audiological evaluation showed absence of acoustic reflex and ABRs. As expected in AN, these subjects exhibited near normal cochlear outer hair cell function as shown in TEOAE & DPOAE recordings. Pure- tone audiometry revealed hearing loss ranging from mild to severe in these patients. Autosomal recessive inheritance patterns were observed in the three families. In Pedigree Ⅰ and Ⅱ, two affected brothers were found respectively, while in pedigree Ⅲ, 2 sisters were affected. All the patients were otherwise normal without evidence of peripheral neuropathy at the time of this writing. Conclusions: In this study, patients with feature of non- syndromic hereditary auditory neuropathy were identified in three Chinese families.Pedigree analysis indicates autosomal recessive inheritances in the pedigrees. The observed inheritance and clinical audiologic findings are different from those previously described for non-syndromic low-frequency sensorineural hearing loss. This information should facilitate future molecular candidate genes screening for understanding the mechanism of AN.

幼年性透明蛋白纤维瘤病一例

报道1例幼年性透明蛋白纤维瘤病的临床表现及实验室特点.患儿1岁起病,以皮肤多发纤维瘤及牙龈增生为特征,智力发育正常.皮损组织病理检查显示表皮正常,结节由纺缍状成纤维细胞样细胞和细胞外均一性玻璃样物质混合构成,正常组织结构破坏.玻璃样物为非纤维性,嗜酸性,成纤维细胞胞质透明,可见模糊的束状排列,无细胞异形性和坏死.PCR扩增毛细血管形态发生因子-2基因17个外显子并测序显示:14号外显子发生纯合的剪接突变IVS14+1G→T,其父母均为该突变的携带者,符合常染色体隐性遗传方式.

婴儿原发性甲状旁腺增生症

原发性甲状旁腺功能亢进症在小儿少见,婴儿病例均由甲状旁腺增生肥大引起.自1947年Pratt~(1)报告第1例以来,至今文献报告已有10多例~(1～9).我们于1984年1月收治1例,经施行甲状旁腺次全切除术后痊愈,报告如下.

原发性小头畸形的临床特征及相关基因的研究进展

原发性小头畸形(Congenital Microcephaly)又称为真性小头畸形或常染色体隐形遗传小头畸形(Autosomal Recessive Primary Microcephaly,MCPH),是一种神经系统发育障碍疾病,其主要临床特征是头围减小伴随一定程度非进行性智力退化[1].小头畸形的病因包括环境因素、遗传因素和感染因素等.目前普遍认为MCPH是一种多基因隐形遗传的疾病.全世界各地报道的发病率差异较大,其中巴基斯坦北部及亚洲一些盛行近亲结婚的国家发病率高,北欧国家发病率较低[2].国内在该领域报道较少,本文通过复习文献,将其临床特征及相关基因研究进展综述如下.