SCA6 is caused by moderate CAG expansion in the alpha1A-voltage- dependent calcium channel gene

Recently, moderate (CAG)>20 repeat expansions in the alpha1A-voltage- dependent calcium channel gene (CACNL1A4) have been identified in a previously unmapped type of SCA which has been named SCA6. We investigated the (CAG)n repeat length of the CACNL1A4 gene in 733 patients with sporadic ataxia and in 46 German families with dominantly inherited SCA which do not harbor the SCA1, SCA2, or MJD1/SCA3 mutation, respectively. The SCA6 (CAG)n expansion was identified in 32 patients most frequently with late manifestation of the disease. The (CAG)n stretch of the affected allele varied between 22 and 28 trinucleotide units and is therefore the shortest trinucleotide repeat expansion causing spinocerebellar ataxia. The (CAG)n repeat length is inversely correlated with the age at onset. In 11 parental transmissions of the expanded allele no repeat instability has been observed. Repeat instability was also not found for the normal allele investigating 431 meioses in the CEPH families. Analyzing 248 apparently healthy octogenerians revealed one allele of 18 repeats which is the longest normal CAG repeat in the CACNL1A4 gene reported. The SCA6 mutation causes the disease in approximately 10% of autosomal dominant SCA in Germany. Most importantly, the trinucleotide expansion was observed in four ataxia patients without obvious family history of the disease which necessitates a search for the SCA6 (CAG)n expansion even in sporadic patients.      

利用CRISPR-Cas9系统敲除小鼠黑色素瘤细胞系MATP基因的初步研究

目的利用CRISPR/Cas9系统,敲除小鼠黑色素瘤细胞系的MATP基因,为MATP基因的功能研究奠定基础。方法利用http://crispr.mit.edu/网站,设计针对MATP的特异性引物,并将引物链接到pCAS9/gRNA1载体。将阳性载体转染小鼠黑色素瘤细胞系B16F10,利用无限稀释的方法获得转染后的单克隆细胞株。提取不同细胞株的基因组,通过测序的方法进一步筛选出发生MATP基因切割的细胞株,并利用Western-blot的方法验证MATP的表达情况。结果成功获得了3株MATP基因敲除的细胞株,Western-blot结果表明,该细胞株不表达MATP蛋白。结论利用pCAS9/gRNA1载体,可以实现B16F10细胞系MATP基因的敲除。     

紫草辅助米非司酮抗早孕对生殖激素的影响

为了探讨紫草辅助米非司酮抗早孕时对早孕妇女血中生殖激素的影响 ,88例早孕妇女随机分成服用米非司酮、紫草、米非司酮加紫草组和空白对照组 ,比较用药前后血人绒毛膜促性腺激素β亚单位 (β-h CG)、卵泡刺激素 ( F SH)、黄体生成素 ( L H)、雌二醇 ( E2 )、孕酮 ( P)和睾酮 ( T)的变化。结果 :单用米非司酮或紫草均对 β-h CG有一定的抑制作用 ,二者合用抑制作用更加明显 ;单用紫草对血中 FSH、 L H有较明显的抑制作用 ,对 E2 、P及 T无明显影响。认为紫草对绒毛功能有一定的影响 ,与米非司酮合用影响更明显 ;紫草对垂体生殖激素有明显的抑制作用。但是否与紫草能提高药物流产效果有关 ,尚需进一步研究。     

Cumulative risk of developing polyps or malignancy at the ileal pouch-anal anastomosis in patients with familial adenomatous polyposis

Restorative proctocolectomy with an ileal pouch-anal anastomosis is performed in an increasing number of patients with familial adenomatous polyposis (FAP). Two techniques are currently used to construct an ileal pouch-anal anastomosis: (1) a double-stapled anastomosis between the pouch and the anal canal and (2) mucosectomy with a hand-sewn iteoanal anastomosis at the dentate line. Although this procedure is thought to abolish the risk of colorectal adenoma, an increasing number of case reports have been published concerning the development of adenoma at the anastomotic site. The purpose of this study was to evaluate the overall cumulative risk of developing adenomatous polyps after ileal pouch-anal anastomosis and to compare the cumulative risk after either anastomotic technique. A total of 126 consecutive FAP patients undergoing a restorative proctocolectomy were identified from polyposis registries in The Netherlands, Denmark, Italy, Germany, and New York. Life-table analysis was used to calculate the cumulative risk of developing polyps in 97 patients with at least 1 year of endoscopic follow-up (median 66 months, range 12 to 188 months). A double-stapled anastomosis was used in 35 patients, whereas in 62 patients a handsewn anastomosis with a mucosectomy was performed. In 13 patients polyps developed at the anastomotic site, four with severe and four with moderate dysplasia. None of the patients developed a carcinoma at the anastomotic site. The cumulative risk of developing a polyp at the anastomotic site was 8% (95% confidence interval 2% to 14%) at 3.5 years and 18% (95% confidence interval 8% to 28%) at 7 years, respectively. The risk of developing a polyp at the anastomotic site within 7 years was 31 % for patients with a double-stapled vs. 10% for patients with a hand-sewn anastomosis with mucosectomy (P = 0.03 [log-rank test]). Because FAP patients undergoing a restorative proctocolectomy with either a double-stapled or hand-sewn anastomosis have a substantial risk of developing adenomatous polyps at the anastomotic site, lifelong endoscopic surveillance is mandatory in both groups. Presented at the Thirty-Ninth Annual Meeting of The Society for Surgery of the Alimentary Tract, New Orleans, La., May 17–20, 1998.     

Effect of nutritional route on colonic anastomotic healing in the rat

Although early enteral feeding has been shown to benefit cutaneous healing when compared to parenteral feeding, the effect of the route of nutritional support in gastrointestinal anastomotic healing has not been defined. The aim of the present study was to determine whether the route of nutritional support influences colonic anastomotic healing. Twenty male Sprague-Dawley rats weighing 270 to 290 grams underwent identical surgical manipulation consisting of central venous catheterization, gastrostomy insertion, and distal colonic anastomosis (single-layer, inverted). Identical nutrient infusates composed of 4.25% amino acids, 25% dextrose, and vitamins were administered, with half the animals receiving the infusions via the gastrostomy and the other half via the venous catheter. Animals were killed 5 days after surgery. There were no differences in nutritional parameters between the parenterally and enterally fed groups. Colonic anastomotic bursting pressure was significantly higher in the enterally fed group (180 ±6 vs. 150±11 mm Hg; P<0.01). The measured insoluble collagen and total protein content in anastootic tissue were enhanced in the enterally supported group. The fraction of soluble (newly synthesized) collagen did not differ between the two groups. The data demonstrate that the route of nutrient administration influences colonic anastomotic healing. The preservation of colonic structural collagen in the enteral group may improve the ability of the gut to hold sutures and thus enhance anastomotic healing. Presented at the Thirty-Ninth Annual Meeting of The Society for Surgery of the Alimentary Tract, New Orleans, La., May 17–20, 1998.     

肝癌患者血清外泌体内miR-665的表达及临床意义

[摘 要] 目的 探讨肝癌患者血清来源的外泌体内miR-665与肝癌临床病理指标及预后的关系。方法 采用试剂盒方法提取患者血清内的外泌体并用透射电镜观察验证。然后利用RT-PCR方法检测30例肝癌患者和10例体检者血清来源的外泌体内miR-665的表达水平,进行对照研究,探讨临床病理指标和预后的关系。结果 血清提取的外泌体呈囊泡状,直径约30～150 nm。肝癌患者血清来源的外泌体miR-665较正常体检者表达水平明显升高,中位表达水平是对照组的8.3倍。外泌体miR-665高表达与患者肿瘤大小（>5 cm） （P=0.0042）、有包膜浸润（P=0.0197）以及临床TNM分期（III～IV期） （P=0.0276）成明显相关,与患者年龄、性别、HBsAg以及AFP水平未见明显相关性（P > 0.05）,外泌体miR-665高表达组患者生存期较低表达组更短（P=0.036）。结论 肝癌患者血清中外泌体miR-665水平升高与肝癌进展相关,测定血清外泌体内miR-665的水平可能有助于肝癌的临床诊断和预后判断。     

心脏瓣膜病合并感染性心内膜炎的外科治疗

目的探讨心脏瓣膜心内膜炎的临床特点、手术时机选择和围术期处理。方法回顾分析26例心脏瓣膜病合并感染性心内膜炎的临床表现、治疗经过和临床预后。结果术前死于恶性心力衰竭1例,术后随访25例,随访时间3个月～6年,无术后死亡,无再发感染。结论心脏瓣膜病合并感染性心内膜炎外科治疗风险大,死亡率高,正确掌握手术指征、术中彻底清除感染灶和围术期正确处理是治疗的关键。