Rapid determination of platelet alloantigen genotypes by polymerase chain reaction using allele-specific primers

BACKGROUND: The technique of allele-specific polymerase chain reaction (PCR) amplification has been adapted for DNA-based human platelet alloantigen typing. STUDY DESIGN AND METHODS: Sequence-specific primers were used to discriminate between the alleles encoding the six major human platelet alloantigens in a series of patients and normal blood donors. RESULTS: This technique allows the direct determination of platelet antigen genotypes from genomic DNA after PCR amplification and agarose gel electrophoresis. It offers significant advantages over previously described techniques for alloantigen identification, as the additional analytical steps of restriction enzyme digestion or dot blot hybridization are not required. The results obtained with this technique correlated precisely with those derived from serologic typing and allele-specific oligonucleotide hybridization. CONCLUSION: The use of allele-specific PCR for platelet alloantigen typing should facilitate the development of DNA-based typing in other regional blood centers and clinical laboratories.     

Cerebrovascular disease: outpatient evaluation with selective carotid DSA performed via a transbrachial approach

A total of 355 outpatients and 73 inpatients were studied for cerebrovascular disease with intraarterial digital subtraction angiography (DSA). The studies were performed by means of selective carotid and vertebral artery catheterization from a transbrachial approach. Selective catheterization of the carotid artery was possible in 95% of patients, with definitive examinations of both extra- and intracranial circulation obtained in 95%-100% of all patients. Vessel opacification was very good to excellent, and the technique was inherently free from artifact caused by vessel overlap or involuntary motion. There were 25 complications, of which 20 were local in nature. Iodine load per case was extremely low, averaging 4.2-7.0 g. Selective carotid and vertebral catheterizations by the brachial route proved to be as safe as intravenous DSA and aortic arch intraarterial DSA with less contrast material load and superior images.     

Fitness testing and career progression in AFL football

Relationships between fitness testing and career progression in the Australian Football League (AFL) are under-explored. This study investigated relationships between anthropometric and fitness tests conducted at the annual AFL National Draft Camp and subsequent career progression of players. A total of 283 players was tested over three consecutive camps (1999-2001). The anthropometric and fitness measures were: height, mass, sum of skinfolds, 20-m sprint test, vertical jump (standing and bilateral running), agility run and a multi-stage incremental shuttle run. The five outcome variables were: drafted (yes/no), AFL debut (yes/no), number of AFL games played to the end of 2003, and subjective ratings of career potential and career value (5-point scale). Of 205 players (72%) subsequently drafted, 166 (59%) eventually made their AFL debut. Players drafted to AFL clubs were faster over 5 m, 10 m and 20 m, ran further in the shuttle run and ran marginally faster in the agility test than players not drafted. Multi-regression analysis showed small to moderate correlations (r = 0.27-0.31) between the designated outcome variables and selected fitness tests: 20-m sprint time (faster), agility run test (faster), and running vertical jump (higher absolute height and smaller difference between left and ride sides). Regression analysis for the standing vertical jump relative to standing reach height showed a counterintuitive negative correlation with positive outcomes, possibly reflecting non-compliance with testing procedures by the less successful athletes. We conclude that the 20-m sprint, jump, agility and shuttle run tests have a small but important association with career progression of AFL footballers.     

活性组织工程神经移植体桥接坐骨神经损伤：存活时间及功能恢复的量化评估

目的:利用组织工程方法制备的神经组织替代物桥接大鼠坐骨神经缺损,观察移植体的存活时间和神经功能指数。方法:实验于2001-04/2003-01在宾夕法尼亚大学神经外科颅脑创伤中心实验室完成。实验方法:利用神经轴索可以体外机械拉长的特性,将背根神经节神经元和拉长的轴索经凝胶处理后,一并卷入可吸收的聚乙醇酸导管内,制备出具有生物学活性的组织工程神经移植体。选用成年雄性SD大鼠40只,按随机数字表法分为4组,每组10只。建立大鼠坐骨神经损伤模型,组织工程替代物移植组将长约12mm的组织工程神经移植体桥接于坐骨神经缺损处;自体神经移植组将切除的坐骨神经近远端调转后重新缝合回缺损处;损伤模型组切除神经后无修复;对照组未造成损伤。实验评估:术后15周,分别对各组大鼠进行行为学评估,比较坐骨神经功能指数,其绝对数值与坐骨神经功能呈负相关。术后16周,处死动物前检测坐骨神经的传导速度,处死动物后行病理学检查,坐骨神经标本切片分别行苏木精-伊红、降钙素基因相关的缩氨酸抗体(背根神经节神经元标记物)、神经丝蛋白和髓鞘染色。结果:40只大鼠全部进入结果分析,无脱失。①术后15周,损伤模型组大鼠的坐骨神经功能指数绝对值高于组织工程替代物移植组和自体神经移植组(-94.3±2.55,-80.0±1.2,-82.7±2.7,P<0.05),两移植组差异无显著性意义(P>0.05)。对照组大鼠的坐骨神经功能指数为(-6.08±1.6),其绝对值显著低于其他3组(P<0.05)。②术后16周,对照组、组织工程替代物移植组、自体神经移植组大鼠的坐骨神经传导速度分别为(51.2±3.1,12.4±2.3,12.0±2.5)m/s,损伤模型组无动作电位引出,对照组大鼠的坐骨神经传导速度高于其他各组(P<0.01),两移植组差异无显著性意义(P>0.05)。③术后16周,自体神经移植组和替代物移植组中,大体检查可见相对正常的神经组织通过缺损区,聚乙醇酸导管基本已完全吸收。苏木精-伊红染色在替代物移植组大鼠的损伤区内发现大量的神经元细胞,降钙素基因相关的缩氨酸抗体和神经丝蛋白双重免疫组织荧光化学检查证实为背根神经节神经元。髓鞘染色可见缺损区内大量髓鞘包裹的轴突。结论:组织工程制备的神经组织替代物能够在移植受体内长期存活,并与受体神经结合促进神经功能恢复,在修复神经缺损、促进功能恢复方面与自体神经具有近似的能力。