经鼻内镜手术进展

颅底手术正随着经鼻内镜手术的发展而发生着转变。经鼻内镜手术最初开发于鼻窦手术,但其适应症已逐渐扩大到其它领域,可以用于治疗大量的疾病。经鼻内镜手术的主要优点是:它利用天然的孔道来处理大量的颅内、鼻窦病变,避免了皮肤切口、面部骨瓣切口、脑回缩等直接开颅所不可避免的后遗症。与传统的神经外科手术相比,发病率和死亡率下降,并间接减少了住院时间和管理成本。本文就经鼻内镜手术的进展进行综述。在综述中阐述了经鼻内镜手术的适应症和基本原则,以及显露、特别是重建技术的进展,这些进展要求在可接受的并发症前提下达到更广泛的切除;讨论了经鼻内镜手术的局限性,尤其是,虽然这种手术往往是"微创",但它并不是完全没有并发症;展望了经鼻内镜手术的适应症会不断拓宽,并发症会越来越少的美好未来。     

Stanford B型主动脉夹层撕破口局部计算流体力学研究

目的:探索Stanford B型主动脉夹层局部血流动力学改变对主动脉夹层发生、发展以及临床预后评估的作用,为临床治疗方案选择提供理论依据。方法:通过CT扫描获取临床常见典型形态的Stanford B型主动脉夹层断层序列,重建出三维主动脉夹层计算流体力学分析模型,对主动脉夹层真假腔内血液流场进行数值模拟计算。结果:血液流经Stanford B型主动脉夹层撕破口时会对血管局部壁面产生冲击,造成动脉管壁局部压强升高,此种"冲击效应"不但会出现在近端夹层撕破口附近管腔壁面,也会出现在中间段及远端夹层撕破口附近,当入口血流压强升高时,夹层撕破口附近局部壁面压强差值也会增加。在心动周期内,Stanford B型主动脉夹层壁面剪切应力异常升高区也主要集中在撕破口区附近的动脉壁面上。结论:对于Stanford B型主动脉夹层而言,撕破口的位置相对于撕破口直径而言似乎更有临床意义。对B型夹层患者采用降低血压治疗,可减低局部动脉管壁上的壁面压强差值,但无法消除此壁面压强差,即主动脉夹层管壁上的局部危险区始终存在。此现象揭示主动脉夹层中远端撕破口也可能是造成夹层局部危险因素的原因,采用手术治疗方法封闭撕破口,以消除局部壁面压强增高区,降低破裂风险,可能是更理想的治疗方法。     

Insect morphology in the age of phylogenomics: innovative techniques and its future role in systematics

A brief account of the history of insect morphology is given. Different techniques and analytical methods used in current projects on insect morphology and phylogeny and their optimized combined application are described. These include fixation, dissection, maceration, histology (microtome sectioning), scanning electron microscopy (SEM), transmission electron microscopy (TEM), serial block‐face scanning electron microscopy (SBFSEM), focused ion beam scanning electron microscopy (FIB/SEM), confocal laser scanning microscopy (CLSM), bleaching, micro‐computed tomography (μCT), computer‐based three‐dimensional reconstruction, focus stacking of digital images, geometric morphometrics and the storage of morphological metadata. The role of insect morphology in the “age of phylogenomics” is discussed.     

Contribution of the skin,rectus abdominis and their sheaths to the structural response of the abdominal wall ex vivo

A better understanding of the abdominal wall biomechanics could help designing new treatments for incisional hernia. In the current study, an experimental protocol was developed to evaluate the contributions of the abdominal wall components to the structural response of the anterior part of the abdominal wall. The specimens underwent 3 dissections (removal of (1) skin and subcutaneous fat, (2) anterior rectus sheath, (3) rectus abdominis muscles). After each dissection, they were subjected to air pressure up to 3 kPa. Ultrasound images and associated elastographic maps were collected at 0, 2 and 3 kPa in the intact state and strains on the internal surface were calculated using stereo-correlation in all states. Strains on the rectus abdominis and linea alba were analyzed. After the dissection of the anterior sheath of the rectus abdominis, longitudinal strain was found significantly different on the linea alba (5% at 3 kPa) and on the rectus abdominis area (11% at 3 kPa). The current results highlight the importance of the rectus sheath in the structural response of the anterior part of the abdominal wall ex vivo. Geometrical characteristics such as thicknesses and radii of curvature and mechanical properties (shear modulus of the rectus abdominis, e.g. at 0 pressure the average value is 14 kPa) were provided in order to facilitate future modeling efforts.     

Recovery of Adult Zebrafish Hearts for High-throughput Applications

Use of the zebrafish model system for studying development, regeneration, and disease is expanding toward use of adult hearts for cell dissociation and purification of RNA, DNA, and proteins. All of these applications demand the rapid recovery of significant numbers of zebrafish hearts to avoid gene regulatory, metabolic, and other changes that begin after death. Adult zebrafish hearts are also required for studying heart structure for a variety of mutants and for studying heart regeneration. However, the traditional zebrafish heart dissection is slow and difficult and requires specialized tools, making large-scale dissection of adult zebrafish hearts tedious. Traditional methods also harbor the risk of damaging the heart during the dissection. Here, we describe a method for dissection of adult zebrafish hearts that is fast, reproducible, and preserves heart architecture. Furthermore, this method does not require specialized tools, is painless for the zebrafish, can be performed on fresh or fixed specimens, and can be performed on zebrafish as young as one month old. The approach described expands the use of adult zebrafish for cardiovascular research.     

瓜实蝇卵巢的发育阶段及分级

瓜实蝇是热带和亚热带地区最重要的经济害虫之一。本研究拟对卵巢发育进行分级,以判断田间捕获的瓜实蝇是否达到性成熟。室内饲养瓜实蝇成虫,对开始羽化至羽化后80 d的不同日龄成虫卵巢进行解剖,并记录了卵巢长度、卵巢宽度、卵巢指数（卵巢长度＆#215;卵巢宽度）和所含卵粒数。将瓜实蝇卵巢发育过程分为4期6个级别,分别为卵黄发生前期（Ⅰ级和Ⅱ级）、卵黄发生期（Ⅲ级和Ⅳ级）、抱卵期（Ⅴ级）、经产期（Ⅵ级）。随着卵巢的发育,Ⅰ～Ⅴ级卵巢长度和宽度迅速增长,卵巢发育成熟开始产卵以后,Ⅵ级卵巢长度和宽度逐渐减小。Ⅰ级和Ⅱ级卵巢长度与宽度大致相等,以后各期卵巢长度均大于宽度。Ⅲ级和Ⅳ级可见清晰的卵室,卵母细胞迅速增长,卵黄逐渐沉积。Ⅴ级可见清晰的卵粒,整个卵巢呈圆柱状。Ⅵ级开始排出卵子,所含卵粒数显著少于Ⅴ级;虽然此级卵巢长度大于Ⅳ级,但卵巢宽度、卵巢指数与Ⅳ级基本一致;Ⅵ级卵巢可见黄体,可结合黄体判定卵巢所处发育级别。本研究对评估粘虫板捕获的瓜实蝇雌虫生理日龄结构有潜在应用价值。     

Dissection and Downstream Analysis of Zebra Finch Embryos at Early Stages of Development

The zebra finch (Taeniopygiaguttata) has become an increasingly important model organism in many areas of research including toxicology^1,2, behavior³, and memory and learning^4,5,6. As the only songbird with a sequenced genome, the zebra finch has great potential for use in developmental studies; however, the early stages of zebra finch development have not been well studied. Lack of research in zebra finch development can be attributed to the difficulty of dissecting the small egg and embryo. The following dissection method minimizes embryonic tissue damage, which allows for investigation of morphology and gene expression at all stages of embryonic development. This permits both bright field and fluorescence quality imaging of embryos, use in molecular procedures such as in situ hybridization (ISH), cell proliferation assays, and RNA extraction for quantitative assays such as quantitative real-time PCR (qtRT-PCR). This technique allows investigators to study early stages of development that were previously difficult to access.     

Isolation of Sensory Neurons of Aplysia californica for Patch Clamp Recordings of Glutamatergic Currents

The marine gastropod mollusk Aplysia californica has a venerable history as a model of nervous system function, with particular significance in studies of learning and memory. The typical preparations for such studies are ones in which the sensory and motoneurons are left intact in a minimally dissected animal, or a technically elaborate neuronal co-culture of individual sensory and motoneurons. Less common is the isolated neuronal preparation in which small clusters of nominally homogeneous neurons are dissociated into single cells in short term culture. Such isolated cells are useful for the biophysical characterization of ion currents using patch clamp techniques, and targeted modulation of these conductances. A protocol for preparing such cultures is described. The protocol takes advantage of the easily identifiable glutamatergic sensory neurons of the pleural and buccal ganglia, and describes their dissociation and minimal maintenance in culture for several days without serum.