Quantitative Computed Tomography and Histological Analysis of Carnivoran Turbinates

食肉龟的定量计算机断层扫描和组织学分析Blaire Van Valkenburgh和Nancy Rawson加州大学洛杉矶分校和Monell化学传感中心哺乳动物的鼻子上有一个复杂的骨骼，由三个纸一样薄的骨卷轴组成，称为甲鱼。最大和最复杂的是上鼻甲，它们在调节呼吸空气和最大限度减少水分损失方面发挥着关键作用。在它们上面和/或后面的是筛鼻器，它们在嗅觉上起作用。最小的是相对简单的鼻甲，位于上颌鼻甲上方，功能不确定。总的来说，海龟和它们的腔室占大多数哺乳动物头部体积的三分之一到一半，但我们对它们的解剖结构以及它们的大小和排列方式在物种之间的差异知之甚少。鉴于复杂的海龟似乎存在于已知的最早的哺乳动物中，并与哺乳动物的两个基本特征--嗅觉和吸热(温血)--有关，因此令人惊讶的是，人们对它们知之甚少。这是因为它们的隐蔽性、内部位置和微妙的结构使它们很难研究。然而，高分辨率CT扫描(HRCT)的最新进展为发现哺乳动物的鼻甲结构打开了大门。对狗和猫的初步研究表明，鼻甲可以通过HRCT进行可视化，首次完整地揭示了这些结构。拟议的研究将扩大和改进这项先前的工作，包括对更广泛的哺乳动物物种的研究，开发复杂的图像分析软件来量化鼻甲结构，以及对覆盖鼻甲的组织进行组织分析，以区分嗅觉和呼吸区域。这项研究汇集了解剖学家、组织学家和计算机科学家，以产生第一个关于鼻子的定量概述，其中整合了任何一组哺乳动物的组织学和骨骼数据。这将为今后更多的鼻甲功能研究奠定基础。毫无疑问，关于鼻甲功能(嗅觉和呼吸)的一些最有趣的问题涉及通过鼻子的流动的各个方面。空气如何被导向嗅觉区域或离开嗅觉区域？是否有可能在有氧运动中引导空气以最大限度地增加流量，或者最大限度地减少流量以加强水和热的保护？这项研究将首次记录哺乳动物鼻甲的基本解剖框架，并为了解包括人类在内的哺乳动物的鼻功能和涉及嗅觉和呼吸的疾病提供必要的基本信息。研究生和本科生将通过这个项目得到培养。CT扫描将进入DigiMorph图书馆，因此将向公众和更广泛的科学界开放。PI计划开发这项研究的各个方面，供处于不利地位的洛杉矶学校科学课程的教师使用。

Quantitative Computed Tomography and Histological Analysis of Carnivoran TurbinatesBlaire Van Valkenburgh and Nancy RawsonUniversity of California-Los Angeles and Monell Chemical Senses CenterThe snout of a mammal houses a complex skeleton made up of three paper-thin scrolls of bone known as the turbinates. The largest and most intricate are the maxilloturbinates, which play a critical role in conditioning respired air and minimizing water loss. Above and/or behind them lie the ethmoturbinates, which function in the sense of smell. The smallest are the relatively simple nasoturbinates that lie above the maxilloturbinates and are of uncertain function. Collectively, the turbinates and their chambers make up a third to a half of the volume of the head in most mammals, and yet we know very little about their anatomy and how they vary in size and arrangement among species. Given that complex turbinates appear to be present in the earliest known mammals and are associated with two fundamental features of mammals, olfaction and endothermy (warm-bloodedness), it is remarkable that so little is known about them. This is because their hidden, internal location and delicate structure make them difficult to study. However, recent advances in high-resolution CT scanning (HRCT) opened the door to discovery of mammalian turbinate structure. Preliminary studies on dogs and cats show that turbinates can be visualized with HRCT, revealing these structures in their entirety for the first time. The proposed research will expand and improve upon this previous work, including study of a wider array of mammal species, development of sophisticated image analysis software to quantify turbinate structure, and a histological analysis of tissues covering the turbinates that will distinguish olfactory versus respiratory regions. This study brings together anatomists, histologists, and computer scientists to produce the first quantitative overview of the nose that integrates both histological and skeletal data in any group of mammals. It will establish the groundwork for much future research on turbinate function. Undoubtedly, some of the most interesting questions about turbinate function (both olfactory and respiratory) concern aspects of flow through the nose. How is air directed to or away from olfactory areas? Is it possible to direct air to maximize flow during aerobic exercise, or to minimize flow to enhance water and heat conservation? This study will document the basic anatomical framework of mammalian turbinates for the first time, and provide fundamental information necessary for understanding nasal function and disorders involving smell and respiration in mammals, including humans. Graduate and undergraduate students will be trained through this project. The CT scans will be entered into the Digimorph library, and will therefore be accessible to the public and broader scientific community. The PI has plans to develop aspects of this research for use by teachers in disadvantaged L.A. school science curricula.