聚肌胞对小鼠的急性毒性和蓄积毒性

目的:测定非病毒类干扰素诱导剂聚肌胞对昆明种小鼠的急性毒性和蓄积毒性。方法:实验于2006-04/05在南京农业大学药理与毒理教研室实验室完成。实材料:聚肌胞注射液(南京富纳生物技术有限公司),批号:060509-3,规格为3mg/mL。清洁级昆明种小鼠购自南京中医药大学实验动物中心(动物生产许可证号为SYXK(苏)2005-0009)。实验方法:①急性毒性实验:选取体质量18～22g的50只小鼠,按随机数字表法分为5组,每组10只,雌雄各半,用药前6h禁食不禁水。在预实验基础上确定各组小鼠聚肌胞注射液用药量,相邻的两组间剂量的比值r为1.2。5组小鼠具体用药剂量为36.17,43.40,52.08,62.50,75.00mg/kg。每只小鼠按0.25mL/10g体质量腹腔注射,不同剂量组按同体积不同浓度给药。②蓄积毒性实验:选取体质量15～18g小鼠60只,随机数字表法分为聚肌胞蓄积毒性实验组40只,对照组20只,各组小鼠雌雄均各半。采用剂量递增连续染毒法来评价聚肌胞的蓄积毒性,以LD50为基础选择剂量,起始剂量为0.1LD50,4d为1期,按1.5倍等比级数递增,分5期共20d。将药用生理盐水配成适合的浓度,每天按体质量1次性腹腔注射给药,每只小鼠给药体积均为0.25mL/10g,连续给药20d,对照组小鼠给予相同容积的生理盐水。实验期间观察小鼠一般表现并按时称体质量,记录小鼠死亡的情况并计算蓄积系数,观察各组小鼠对聚肌胞的耐受性。结果:110只小鼠均进入结果分析。①急性毒性实验:各组小鼠注射聚肌胞后均表现行动迟缓,精神沉郁,畏寒扎堆,被毛竖立,用药后3h呈现不同程度的腹泻,4h后相继出现死亡。小鼠的死亡多集中在用药后4～12h,用药后24h未死亡小鼠的精神、食欲都逐渐恢复,继续观察6d未见小鼠再有死亡。小鼠腹腔注射聚肌胞注射液的LD50为59.73mg/kg,LD5095%可信限为:29.49～120.97mg/kg。②蓄积毒性实验:实验组小鼠未发现有明显毒性反应,无小鼠死亡。实验组小鼠体质量与对照组相比差异不显著(P>0.05)。③耐受性实验:实验组小鼠死亡率明显低于对照组(0,20%,P<0.01)。结论:聚肌胞腹腔注射对小鼠毒性较大,但相对于临床应用剂量,聚肌胞注射液的使用仍较为安全;聚肌胞注射液对小鼠没有或仅有轻微的蓄积毒性,小鼠对本品可产生明显的耐受性。     

Beliefs about Alzheimer's disease in Britain

Objectives: Alzheimer's disease (AD) represents one of the most debilitating conditions affecting the elderly. Despite the prevalence and consequences of AD, surveys have revealed that the general public in North America and Australia hold numerous misconceptions of the disease. The aim of this study was to examine whether misconceptions of AD are also endorsed by adults in Britain.

Method: The Alzheimer's disease knowledge scale (ADKS) was completed by 312 adults residing in Lincolnshire, UK. The ADKS contains 30 true or false statements pertaining to risk factors, assessment and diagnosis, symptoms, course, life impact, caregiving, and treatment and management of AD.

Results: Regardless of age, education, and familiarity with AD, respondents in this survey demonstrated a good understanding (≥80% mean correct) of some items from all categories. However, knowledge gaps exist about the course of the disease, and of conditions that can exacerbate (inadequate nutrition) or simulate (depression) the symptoms of AD. Moreover, a large proportion of respondents (～75%) are unaware that hypertension or hypercholesterolemia may increase ones predisposition to developing AD.

Conclusion: Respondents revealed knowledge gaps pertaining to conditions that masquerade as AD, increase ones vulnerability to AD, and exacerbate AD symtomatology. Educational campaigns that specifically target these issues may help reduce the impact of AD.     

A chemically defined carrier for the delivery of human mesenchymal stem/stromal cells to skin wounds

Skin has a remarkable capacity for regeneration, but age- and diabetes-related vascular problems lead to chronic non-healing wounds for many thousands of U.K. patients. There is a need for new therapeutic approaches to treat these resistant wounds. Donor mesenchymal stem/stromal cells (MSCs) have been shown to assist cutaneous wound healing by accelerating re-epithelialization. The aim of this work was to devise a low risk and convenient delivery method for transferring these cells to wound beds. Plasma polymerization was used to functionalize the surface of medical-grade silicone with acrylic acid. Cells attached well to these carriers, and culture for up to 3 days on the carriers did not significantly affect their phenotype or ability to support vascular tubule formation. These carriers were then used to transfer MSCs onto human dermis. Cell transfer was confirmed using an MTT assay to assess viable cell numbers and enhanced green fluorescent protein-labeled MSCs to demonstrate that the cells post-transfer attached to the dermis. We conclude that this synthetic carrier membrane is a promising approach for delivery of therapeutic MSCs and opens the way for future studies to evaluate its impact on repairing difficult skin wounds.     

钙依赖性磷脂结合蛋白Annexin Ⅱ的研究进展

Annexin Ⅱ是Annexins超家族中A亚家族的重要成员,具有钙离子介导的磷脂结合特性. 主要表达在人体内皮细胞、单核/巨噬细胞、骨髓细胞和某些肿瘤细胞中. 本文着重就Annexin Ⅱ的基因结构、蛋白结构、生物学功能及其与疾病的关系进行阐述.     

Reverse dot-blot detection of the African-American beta-thalassemia mutations

DNA-based diagnosis of the beta thalassemias provides accuracy to newborn screening genetic counseling, and prenatal diagnosis. However, the use of polymerase chain reaction (PCR)-based methods is challenged by the great number of different-beta-thalassemia mutations that exist even within defined ethnic groups. In this regard, the reverse dot-blot method offers a means of screening for several mutations with a single hybridization reaction. We have applied the reverse dot-blot method to the detection of the beta-thalassemia mutations of African-Americans. We used two biotin-labeled primer pairs in a duplex reaction to amplify and label two beta-globin target DNA fragments that encompass all known African-American beta-thalassemia mutations. The PCR products were denatured and hybridized to polyT-tailed, membrane-fixed, allele- specific probe pairs for the hemoglobin (Hb) S, Hb C, and 14 beta- thalassemia mutations and their corresponding wild-type sequences. Seven common mutations plus Hb S and Hb C were included on one diagnostic strip, and seven less common beta-thalassemia mutations were included on another strip. Carefully controlled, high stringency hybridization allowed accurate distinction of these alleles. Reverse dot-blot diagnosis of the less common beta-thalassemia mutations precludes the need for alternative, more technically challenging methods. This method provides a rapid, accurate method for diagnosis of beta thalassemia among African-Americans and other ethnic groups in which beta thalassemia occurs.     

Outcome of orthotopic liver transplantation in patients with haemophilia

Background—Many patients with haemophilia havedeveloped cirrhosis or hepatocellular carcinoma due to transfusionacquired chronic viral hepatitis.
Aims—To assess the long term outcome of allhaemophilic patients reported to have undergone orthotopic liver transplantation.
Methods—Transplant centres of patients identifiedby medical database search were contacted and survival data assessed by Kaplan-Meier analysis.
Results—Twenty six haemophilic men (median age 46 years, range 5-63 years) underwent orthotopic liver transplantation in16centres between 1982 and 1996. Indications for transplantation werehepatitis C cirrhosis (69%), hepatitis B with or without C cirrhosis(15%), viral hepatitis related hepatocellular carcinoma (12%), andbiliary atresia (4%). Six patients (23%) were infected with humanimmunodeficiency virus (HIV). Postoperatively, the median time tonormal clotting factor levels was 24 hours (range 0-48 hours) andexogenous clotting factors were stopped at a median of 24 hours (range0-480 hours). Four patients (15%) had bleeding complications. The oneand three year survival of HIV positive recipients (67% and 23%) wassignificantly poorer (p=0.0003) than that of HIV negative recipients(90% and 83%). Coagulopathy was cured in all patients surviving morethan 12 days post-transplant. Six of the 20 patients (30%) withhepatitis C cirrhosis pretransplant had evidence of disease recurrenceat a mean of nine months post-transplant.
Conclusions—Hepatitis C cirrhosis is the mostcommon indication for orthotopic liver transplantation in patients withhaemophilia. Transplantation results in long term cure of haemophiliabut may be complicated by the effects of HIV infection or recurrentviral hepatitis.

Keywords:liver transplantation; haemophilia; hepatitis C; cirrhosis; HIV