动脉瘤性蛛网膜下腔出血后迟发性脑缺血的早期凝血及纤溶生物标志物变化

目的通过对动脉瘤性蛛网膜下腔出血(aSAH)后早期血液凝血和纤溶相关标志物进行动态分析,探讨其与迟发性脑缺血(DCI)之间的关系,尝试从临床角度阐述微血栓形成机制在DCI发生发展中可能的潜在影响。方法前瞻性连续纳入2016年12月至2018年6月北京天坛医院发病3 d内的aSAH住院患者165例。入院后按照统一标准化方案分别采集患者入院时、发病后(4±1)、(7±1)、(10±1)、(13±1)d的血液样本,记录DCI患者及非DCI患者各时间点的部分血液凝血[包括凝血酶原时间(PT)、活化部分凝血活酶时间(APTT)、血小板计数、血管性血友病因子(vWF)抗原定量和vWF活性]及纤溶相关标志物参数(D-二聚体、纤维蛋白原)。PT、APTT、纤维蛋白原水平通过凝血酶测定,D-二聚体含量通过乳胶光度法测定,vWF抗原定量和vWF活性检测分别采用vWF抗原检测试剂盒和vWF活性检测试剂盒,并对两组间不同时间点各参数进行重复测量方差分析。结果DCI发生率为31.5%(52/165)。凝血及纤溶标志物相关结果显示,DCI患者在aSAH后早期即出现血管性血友病因子(vWF)抗原含量和活性升高,并在发病后(7±1)d达到高峰,DCI患者vWF抗原及活性水平较非DCI患者更高,两组间差异具有统计学意义(F值分别为6.873、5.784,P值分别为0.017、0.021),同时vWF抗原及活性水平与时间相关(F值分别为105.448、89.141,均P<0.01),且存在组别与采样时间之间的交互效应(F值分别为9.525、10.114,P值分别为0.022、0.016)。此外,DCI与不同采样时间对PT、APTT、血小板计数、D-二聚体、纤维蛋白原等水平无明显影响(均P>0.05),并且两组别与时间不存在交互作用(均P>0.05)。结论DCI患者vWF抗原含量及活性明显高于非DCI患者,提示可能存在微血栓形成,动态监测vWF抗原含量及活性有助于早期发现DCI。     

Traumatic abdominal wall hernia: Delayed repair: Advantageous or taxing

INTRODUCTIONTraumatic abdominal wall hernia (TAWH) is a rare entity. Most cases occur in children, following an injury from the bicycle handle bar. In adults, it usually results from road traffic accidents (RTA). We present one of the largest reported cases of TAWH following RTA managed by delayed mesh repair.PRESENTATION OF CASEA 35 yr old obese male with RTA was diagnosed with TAWH with 19 cm × 15 cm defect in left flank. As there were no intra abdominal injuries and overlying skin was abraded, he was planned for elective repair after 6 months. On exploration a defect of 30 cm × 45 cm was found extending from midline anteriorly to 8 cm short of midline posteriorly in transverse axis and costal margin to iliac crest in craniocaudal axis. After restoration of bowel into abdominal cavity, primary closure or even approximation of muscular defect was not possible thus a mesh closure using 60 cm × 60 cm prolene mesh in subcutaneous plane was done. After 4 months follow up, patient is healthy and has no recurrence.DISCUSSIONEmergent surgical management of TAWH is usually favoured due to high incidence of associated intra abdominal injuries. Delayed repair may be undertaken in selected cases.CONCLUSIONTAWH, although rare, should be suspected in cases of RTA with abdominal wall swellings. With time, the hernia defect may enlarge and muscles may undergo atrophy making delayed repair difficult.     

Grasping without vision: Time normalizing grip aperture profiles yields spurious grip scaling to target size

The analysis of normalized movement trajectories is a popular and informative technique used in investigations of visuomotor control during goal-directed acts like reaching and grasping. This technique typically involves standardizing measures against the amplitude of some other variable – most typically time. Here, we show that this normalizing technique can lead to some surprising results. In the first of two experiments, we asked participants to grasp target objects without ever seeing them from trial to trial. In the second experiment, participants were given a brief preview of the target and were then cued 3 s later to pick it up while vision was prevented. Critically, on some trials during the delay period and unbeknownst to the participants, the previewed target was swapped for a new unseen one. The results of both experiments show that time-normalized measures of grip aperture during the closing phase of the movement appear to be scaled to target size well before the fingers make contact with the target – even though participants had no idea what the size of the target was that they were grasping. In contrast, a classical measure of anticipatory grip scaling, maximum grip aperture, did not show scaling to target size. As we demonstrate, however, in both experiments, movement time was longer for the larger target than the smaller ones. Thus, the comparisons of time-normalized grip aperture, particularly during the closing phase of the movements, were made across different points in real time. Taken together, the results of these experiments highlight a need for caution when investigators interpret differences in time-normalized dependent measures – particularly when the effect of interest is correlated with the dependent measure and a third variable (e.g., movement time) that is used to standardize the dependent measure.