The peculiar properties of the falx and tentorium in brain injury biomechanics

The influence of the falx and tentorium on brain injury biomechanics during impact was studied with finite element (FE) analysis. Three detailed 3D FE head models were created based on the images of a healthy, normal size head. Two of the models contained the addition of falx and tentorium with material properties from previously published experiments. Impact loadings from a reconstructed concussive case in a sport accident were applied to the two players involved. The results suggested that the falx and tentorium could induce large strains to the surrounding brain tissues, especially to the corpus callosum and brainstem. The tentorium seemed to constrain the motion of the cerebellum while inducing large strain in the brainstem in both players involved in the accident (one player had mainly coronal head rotation and the other had both coronal and transversal rotations). Since changed strain levels were observed in the brainstem and corpus callosum, which are classical sites for diffuse axonal injuries (DAI), we confirmed the importance of using accurate material properties for falx and tentorium in a FE head model when studying traumatic brain injuries.     

Genomic analysis reveals association of specific SNPs with athletic performance and susceptibility to injuries in professional soccer players

The development of specific and individualized training programs is a possible way to improve athletic performance and minimize injuries in professional athletes. The information regarding the sport's physical demands and the athletes’ physical profile have been, so far, considered as exhaustive for the design of effective training programs. However, it is currently emerging that the genetic profile has to be also taken into consideration. By merging medical and genetic data, it is thus possible to identify the athlete's specific attitude to respond to training, diet, and physical stress. In this context, we performed a study in which 30 professional soccer players, subjected to standard sport medical evaluation and practices, were also screened for genetic polymorphism in five key genes (ACTN3, COL5A1, MCT1, VEGF, and HFE). This genetic analysis represents the central point of a multidisciplinary method that can be adopted by elite soccer teams to obtain an improvement in athletic performance and a concomitant reduction of injuries by tailoring training and nutritional programs. The genetic fingerprinting of single athletes led to the identification of two performance-enhancing polymorphisms (ACTN3 18705C>T, VEGF-634C>G) significantly enriched. Moreover, we derived a genetic model based on the gene set analyzed, which was tentatively used to reduce athletes’ predisposition to injuries, by dictating a personalized nutrition and training program. The potential usefulness of this approach is concordant with data showing that this team has been classified as the healthiest and least injured team in Europe while covering the highest distance/match with the highest number of high-intensity actions/match.     

Antibodies to T cell receptors and to histocompatibility antigens

The injection of 10⁶ parental strain spleen cells into adult F1 hybrid mice resulted in the formation of two serum activities: anti-receptor antibodies and alloantibodies. To demonstrate the respective roles of T and B cells in the elicitation of these serum activities, parental strain lymphoid cell suspensions containing varying proportions of T and B cells, or consisting only of T or B cells, were employed as inocula for F1 mice. The results indicated that the injection of pure T cells led to the formation of antireceptor antibodies only, while the injection of pure B cells resulted exclusively in formation of alloantibodies, suggesting that anti-receptor antibodies were structures elicited by T cell receptors. Alloantibodies appear to be formed as a consequence of the interaction of B cell receptors with alloantigen.     

An innovative numerical approach to resolve the pulse wave velocity in a healthy thoracic aorta model

Aortic dissection and atherosclerosis are highly fatal diseases. The development of both diseases is closely associated with highly complex haemodynamics. Thus, in predicting the onset of cardiac disease, it is desirable to obtain a detailed understanding of the flowfield characteristics in the human cardiovascular circulatory system. Accordingly, in this study, a numerical model of a normal human thoracic aorta is constructed using the geometry information obtained from a phase-contrast magnetic resonance imaging (PC-MRI) technique. The interaction between the blood flow and the vessel wall dynamics is then investigated using a coupled fluid–structure interaction (FSI) analysis. The simulations focus specifically on the flowfield characteristics and pulse wave velocity (PWV) of the blood flow. Instead of using a conventional PC-MRI method to measure PWV, we present an innovative application of using the FSI approach to numerically resolve PWV for the assessment of wall compliance in a thoracic aorta model. The estimated PWV for a normal thoracic aorta agrees well with the results obtained via PC-MRI measurement. In addition, simulations which consider the FSI effect yield a lower predicted value of the wall shear stress at certain locations in the cardiac cycle than models which assume a rigid vessel wall. Consequently, the model provides a suitable basis for the future development of more sophisticated methods capable of performing the computer-aided analysis of aortic blood flows.     

CBL+PBL与PBL教学法在胸腔外科临床教学中的对比分析

目的:对比PBL教学法,研究CBL+PBL法在五年制临床医学本科胸腔外科临床教学中的应用及效果。方法:抽取五年制本科临床实习生共59人,随机分为实验组(29人)与对照组(30人),实验组采用CBL+PBL教学法讲授临床实践课,对照组采用单纯PBL法。授课结束后进行随堂测试及问卷调查。结果:①随堂测试:实验组病例分析题及总成绩高于对照组且差异有统计学意义(P0.05),选择题与简答题两组间成绩比较无统计学差异。②问卷调查:在是否有利于培养临床思维能力以及是否有利于理论联系临床问题中,实验组肯定回答的人数比例均高于对照组且差别有统计学意义。(P0.05)。两组之间在是否有利于提高学习兴趣、是否有利于提高团队协作能力、是否有利于知识的理解以及是否赞同本教学方法问题中,差异无统计学意义。结论:CBL+PBL教学法相对于单纯的PBL教学法而言,更适合在临床教学中应用。     

PBL教学法与批判性思维在医学本科生胸外科临床教学中的应用研究

目的:对比研究以问题为中心教学法(PBL)与基于课堂的学习法(LBL),观察批判性思维在医学本科生胸外科临床教学中的作用。方法:随机选取我院本科临床专业学生160名,随机分为PBL教学组及LBL教学组各80人。在学习结束时,采用不记名问卷调查,进行批判性思维能力和教学效果、教学模式的评价。结果:结果显示PBL教学法在批判性思维培养方面优于LBL教学法,且教学效果及教学模式也更受支持。结论:采用PBL教学法有助于提高学生的批判性思维,可有效提高学习效果。     

医源性胆管损伤行肝切除术的指征探讨

医源性胆管损伤(IBDI)是腹腔镜胆囊切除术中最常见的并发症。复杂的医源性胆管损伤涉及肝汇流的中断和肝脏血管的损伤,对复杂的医源性胆管损伤患者施行的肝部分切除的目的是去除血管或感染性病变引起的肝实质纤维化和肝萎缩,可以彻底消除胆道狭窄、胆汁淤积及反复发作的胆管炎。肝切除术在医源性胆管损伤的手术治疗中并不是一个标准及必需的程序,但却应被视为对胆囊切除术后胆管损伤外科治疗中的一部分。     

微创胸腔闭式引流精密可控负压吸引术治疗原发性自发性气胸的疗效及患者疼痛、氧化应激反应观察

摘要 目的：探究微创胸腔闭式引流精密可控负压吸引术治疗原发性自发性气胸（PSP）的疗效及对患者疼痛、氧化应激反应的影响。方法：选取2019年1月~2021年1月我院收治的PSP患者120例,以随机数表法分成研究组与对照组,各自60例。给予对照组微创胸腔常规闭式引流治疗,研究组则给予微创胸腔闭式引流精密可控负压吸引术治疗。比较两组患者的临床疗效,术后6 h、1 d及3 d的疼痛评分（VAS）,术前及术后1 d的血清氧化应激指标[超氧化物歧化酶（SOD）、丙二醛（MDA）]水平以及术后并发症发生情况。结果：研究组临床疗效的总有效率为91.67%,显著高于对照组的78.33%（P<0.05）,且研究组患者术后6 h、术后1 d以及术后3 d的VAS评分均显著低于对照组（P<0.05）。术后研究组患者SOD水平显著高于对照组（P<0.05）,同时MDA水平显著低于对照组（P<0.05）。另外研究组患者的总并发症发生率为3.33%,显著低于对照组的13.33%（P<0.05）。结论：微创胸腔闭式引流精密可控负压吸引术治疗PSP的疗效肯定,能减轻患者的疼痛程度及氧化应激反应,且能减少术后并发症的发生率。     

Possible relationship of cranial traumatic injuries with violence in the south‐east Iberian Peninsula from the Neolithic to the Bronze Age

The main aim of this study was to analyze the presence and distribution of cranial trauma, as possible evidence of violence, in remains from the Neolithic to Bronze Age from the SE Iberian Peninsula. The sample contains skulls, crania, and cranial vaults belonging to 410 prehistoric individuals. We also studied 267 crania from medieval and modern times for comparative purposes. All lesions in the prehistoric crania are healed and none of them can be attributed to a specific weapon. In all studied populations, injuries were more frequent in adults than in subadults and also in males than in females, denoting a sexual division in the risk of suffering accidents or intentional violence. According to the archeological record, the development of societies in the SE Iberian Peninsula during these periods must have entailed an increase in conflict. However, a high frequency of cranial traumatic injuries was observed in the Neolithic series, theoretically a less conflictive time, and the lowest frequency was in crania from the 3rd millennium B.C. (Copper Age), which is characterized by the archeologists as a period of increasing violence. The relatively large size and the high rate of injuries in Neolithic crania and the practice of cannibalism are strongly suggestive of episodes of interpersonal or intergroup conflict. The number and distribution of injuries in Bronze Age is consistent with the increase in violence at that time described by most archeologists. Am J Phys Anthropol, 2009. © 2009 Wiley‐Liss, Inc.