Adjuncts to transcatheter aortic valve implantation

Introduction: The appreciable rise in percutaneous valve procedures has been pursued by a wave of development in advanced technology to help guide straightforward, streamlined and safe intervention. This review article aims to highlight the adjunctive devices, tools and techniques currently used in transcatheter aortic valve implantation procedures to avoid potential pitfalls.

Areas covered: The software and devices featured here are at the forefront of technological advances, most of which are not yet in widespread use. These products have been discussed in national and international structural intervention conferences and the authors felt it important to showcase particularly well designed adjuncts that improve procedural efficacy and safety. Whilst vascular pre-closure systems are used routinely and are an integral part of these complex cardiovascular procedures, these have been well summarised elsewhere and are beyond the scope of this article.

Expert commentary: The rising volume of patients with aortic stenosis who are treatable with TAVI means that this exponential increase in procedures must be accompanied by a steady decline in procedural complications. This section provides an overview of our current perspective, and what we feel the direction of travel will be.     

Regulatory mechanisms in cell-mediated immune responses. VI. Interaction of H-2 and non-H-2 genes in elaboration of mixed leukocyte reaction suppressor factor

Previous studies have shown that alloantigen-activated spleen T cells produce a soluble factor which suppresses mixed lymphocyte reaction proliferative responses, and that the interaction between suppressor and responder cells is controlled by genes of the H-2 complex. However a defect in the expression of suppressor activity was identified in the mouse strain C57BL/6J. Factor prepared from alloactivated B6 spleen cells failed to suppress MLR responses of syngeneic or H-2 compatible responder cells. Unimpaired suppressor factor production by other H-2 (b) strains and failure of suppressor factor production by a B6 congenic strain, B6.C-H-2(d) isolated the defective gene to the non-H-2 portion of the genome. In addition, the defect appeared to be related specifically to inability to produce an active factor, while the capacity to respond to suppressor molecules was unimpaired. The genetic character of the non-H-2 gene action was identified in F1 hybrid studies. Initially F(1) hybrids of the nondefective histoincompatible strains were studied. Suppressor factor from F1 cells suppressed the responses of both parental strains, and parental factors each suppressed the response of F(1) cells. Adsorption of F(1) factor with Con A-activated thymocytes of either parental strain removed suppressor activity specific for that strain, leaving activity against the other parental strain intact. The data support cedominant expression and production of distinct, parental H-2 haplotype-specific suppressor molecules by F(1) suppressor cells. An F(1) hybrid of the defective B6 strain with nondefective BALB/c produced suppressor factor which was also capable of suppressing both parental strains. Production of a suppressive B6-reactive factor by F(1) cells was verified by adsorption studies. Thus it appears that non-H-2 genes of the BALB/c parent acted in a genetically dominant fashion to provide the function required for expression of B6 suppressor molecules. We conclude that multiple genes control the expression of alloactivated suppressor cell activity, with at least one gene mapped to the I-C subregion of the murine major histocompatibility complex and one or more genes mapped to the non-H-2 gene complement.     

Role of prostaglandin E in the biphasic fever response to endotoxin

Biphasic fevers were induced in sheep with intravascular infusions or injections of 4-10 μg (80-200 ng/kg) of endotoxin, whereas monophasic fevers were obtained with doses of 1-2/μg (20-40 ng/kg). A marked increase in arterial blood pressure invariably accompanied the onset of fever; the latency of responses to the higher and lower doses of endotoxins averaged 26 min and 42 min, respectively. Prostaglandin (PG) assays of plasma from the carotid artery and jugular vein during fever episodes revealed a surge of PGE and PGF coincident with the pressor response and the first phase of fever, but PG were not detected in plasma samples taken throughout the second phase of fever. PG measurements of arterial and venous plasma collected at a distal site (hind limb) showed a similar surge of PGE and PGF in association with the early fever response, indicating that intravascular PG synthesis and release represents a generalized systemic response to circulating endotoxin. Carotid arterial infusions of PGE(2) produced immediate monophasic fevers and pressor responses, whereas PGD(2) infusions produced an immediate pressor effect but no fever. Infusions of PGF(2α) or prostacyclin, however, evoked neither fever nor pressor effects. Intracarotid infusions of leukocyte pyrogen (LP) caused monophasic fevers with latent periods of 15-20 min but pressor responses were not seen and neither PGE nor PGF were detected in plasma samples from the carotid artery or jugular vein before or during fever. Indomethacin, a potent inhibitor of arachidonic acid metabolism, blocked fever responses to endotoxin and to LP. These findings implicate PGE as the mediator of the early phase of endotoxin fever and imply a role for another pyrogenic metabolite ofarachidonic acid in the mediation of the second phase of fever, i.e., the phase associated with circulating LP. It is possible that both pyrogenic metabolites are generated within the vascular compartment, reaching thermoregulatory centers of the brain by transfer across the blood-brain interface.     

GABAergic hyperinnervation of dentate granule cells in the Ts65Dn mouse model of down syndrome: Exploring the role of App

It has been suggested that increased GABAergic innervation in the hippocampus plays a significant role in cognitive dysfunction in Down syndrome (DS). Bolstering this notion, are studies linking hyper‐innervation of the dentate gyrus (DG) by GABAergic terminals to failure in LTP induction in the Ts65Dn mouse model of DS. Here, we used extensive morphometrical methods to assess the status of GABAergic interneurons in the DG of young and old Ts65Dn mice and their 2N controls. We detected an age‐dependent increase in GABAergic innervation of dentate granule cells (DGCs) in Ts65Dn mice. The primary source of GABAergic terminals to DGCs somata is basket cells (BCs). For this reason, we assessed the status of these cells and found a significant increase in the number of BCs in Ts65Dn mice compared with controls. Then we aimed to identify the gene/s whose overexpression could be linked to increased number of BCs in Ts65Dn and found that deleting the third copy of App gene in Ts65Dn mice led to normalization of the number of BCs in these mice. Our data suggest that App overexpression plays a major role in the pathophysiology of GABAergic hyperinnervation of the DG in Ts65Dn mice. © 2016 Wiley Periodicals, Inc.     

胶原蛋白膜对人牙周膜细胞增殖能力量效分析的影响

目的:观察不同质量浓度胶原蛋白膜对人牙周膜细胞增殖能力的影响,寻求牙周组织工程中胶原蛋白膜载体的最佳浓度。方法:实验于2006-02/11在辽宁医学院实验中心完成。实验材料:选取因正畸需要拔除的新鲜第一前磨牙,患者知情同意并自愿捐献。实验分组:通过热烘干法制备胶原蛋白膜(胶原质量浓度分别为3,6,9g/L)。将细胞浓度为5×107L-1的第3～8代的人牙周膜细胞接种到3,6,9g/L胶原蛋白膜上,每种薄膜设立3个样本。分别将负载细胞的薄膜移至24孔板中,对照组为细胞直接接种于24孔板中。实验评估:①复合培养第7天对人牙周膜细胞进行细胞记数。②利用扫描电镜观察人牙周膜细胞在胶原蛋白膜上的生长情况。结果:①复合培养第7天人牙周膜细胞记数:随着培养时间的增长,3,6,9g/L胶原蛋白膜上的细胞数量逐渐增加[分别为(3.63±0.59)×104,(3.92±0.10)×104,(4.26±0.24)×104个],9g/L胶原蛋白膜上的细胞生长最旺盛,均高于对照组(2.51±0.11)×104个,4组之间比较差异均有显著性意义(t=3.263,17.099,11.611,P<0.05)。②扫描电镜下人牙周膜细胞在胶原蛋白膜上的生长情况:复合培养1周,胶原蛋白膜具有较好的多孔状结构;人牙周膜细胞伸出多个伪足样突起,紧密贴附在材料表面,细胞沿材料的孔隙边缘生长。结论:9g/L胶原蛋白膜最适合人牙周膜细胞生长增殖。     

精神分裂症患者的社交技能训练小组活动方案

目的:通过社交技能训练让精神分裂症患者明确正确的沟通方式,锻炼自己的交谈能力,学会社会交往技巧,体会人与人之间的关系,学会分析解决社交过程中出现的问题,从而掌握社会交往的技能,防止或延缓发生严重的社会功能衰退。方法:选择早期精神分裂症患者(5年内),在住院治疗达到临床治愈出院后立即开始训练。活动以小组为单位(10人1组)进行,小组成员相对固定。前3个月每个月1次,以后每3个月1次,持续1年。活动过程中以游戏为主导,让组员在游戏中领会人际交往过程中的要领。具体训练方案包括6个方面:①训练一:语言表达能力,正确的沟通方式。②训练二:如何寻找帮助。③训练三:指导患者学习人际交往的基本技巧。④训练四:如何与人打交道。⑤训练五:合作。⑥训练六:社交问题的解决。结果:通过增加对社交时恐惧的暴露及社交技巧训练,对精神分裂症伴发社交恐惧症有效;但对精神分裂症意志活动减退所致社交时主动性不足效果较差。结论:对精神分裂症患者的社交训练应尽早进行,同时在设计精神分裂症社交训练时应加强对患者主动性不足的针对性。     

应用事件相关电位技术考察正常人名词和动词的脑区分布特征

目的：应用事件相关电位技术考察正常人脑区名词和动词的分布特征. 方法：实验于2006-03在徐州师范大学完成.选择在校大学生16名作为受试者,男女各8名,年龄19～22岁,进行词语搭配判断实验.①刺激材料包括180个启动刺激（“一Q”和“不M”,Q为名量词,M为能愿动词）,以及180个目标刺激（名词和动词）.启动词和目标词构成4组不同搭配的短语,其中2组为正确搭配,另2组为错误搭配.②实验任务：要求被试判断启动词和目标词的搭配是否正确.刺激材料为随机编排,启动词和目标词的呈现时间均为200 ms,启动词和目标词之间的时间间隔为300 ms,相邻两个trail间的时间间隔为2 500 ms.③实验评估：采用Neuroscan Synamps 2记录脑电,并使用Neuroscan 4.3对采集的脑电进行离线分析处理.最后用两因素重复测量的方差分析法对数据进行分析. 结果：16名被试的实验数据均纳入统计分析.①反应时和正确率：两种正确搭配短语“一Q＋名词”和“不M＋动词”反应时比较差异显著[F（1,30）=5.475,P=0.026];而二者的正确率未见显著效应.②Nd400的平均幅值：在目标刺激呈现后350～750 ms,额区Nd400的类型主效应十分显著[F（1,15）=14.211,P=0.002],“不M＋名词”-“不M＋动词”差异波Nd400成分在额区显著.在目标刺激呈现后450～530 ms,后部脑区Nd400的类型主效应十分显著[F（1,15）=11.042,P=0.005],“一Q＋动词”-“一Q＋名词”差异波Nd400更负.③潜伏期：在后部脑区,两个差异波的Nd400在潜伏期上差异也十分显著[F（1,15）=29.512,P=0.000],差异波“一Q＋动词”-“一Q＋名词”所诱发的Nd400更加延迟.④脑区电压分析：在目标词呈现后400～600 ms,差异波“不M＋名词”-“不M＋动词”在额区的电压更负,而“一Q＋动词”-“一Q＋名词”则在中央顶区有更负的电压值. 结论：对于正常人而言,名词和动词具有不同的大脑皮质表征,额区主要负责动词的加工,而后部脑区在名词的表征中起主要作用.     

Rh phenotypes of Chinese blood donors in Hong Kong, with special reference to weak D antigens

Among Hong Kong Chinese blood donors, 99.71 percent were found to be D+. Of these, 55.02 percent were of the phenotype CCDee. The Du phenotype was found to be present in 0.016 percent. Among the 0.27 percent who were apparently D-, 0.079 percent were of the Del phenotype, while the remaining 0.19 percent were "true D-," as defined by a nonreactive eluate obtained by an adsorption and elution procedure using anti-D. The ccdee phenotype constitutes 56.77 percent of the "apparent D-" and 80.24 percent of the true D-. Data show that anti-D rarely occurs in Hong Kong Chinese, and it is postulated that this could be due to the presence of a very weak form of the D antigen among many of those who appear to be D-.