Defining "True" Paranasal Sinuses: Histological Indicators of Secondary Pneumatization

定义“真正的”鼻旁窦：二次气化的组织学指标

• 批准号: 0820751
• 负责人: Tim Smith
• 金额: $ 2.13万
• 依托单位: Slippery Rock University of Pennsylvania
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-01 至 2011-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0820751&HistoricalAwards=false
• 关键词: Defining; True; Paranasal; Sinuses; Histological

The recent use of computed tomography (CT) to study paranasal sinuses has resulted in a renewed focus on the phylogenetic significance and function of these mucosa-lined cranial cavities. However, identification of sinuses via CT is complicated because even mammals that lack true sinuses have concave regions (termed recesses) of the nasal cavity that can be mistaken for them. The difference is developmental; these recesses are simply the product of ossification of the cartilaginous nasal capsule, while true sinuses develop by a process known as pneumatization in which bone (and possibly cartilage) is actively removed by special cells (osteoclasts). To date, no study has documented the histological and cellular characteristics of these divergent processes, which lead to very different cranial shapes among species, and may well underlie developmental anomalies of clinical importance within mammalian species (including humans). In this project, the researchers will determine if microscopic distinctions exist between spaces that form identifiable paranasal sinuses versus the comparable natal recess in nonhuman primates. They will study cadaveric neonates of primates that do and do not develop maxillary and/or frontal sinuses, comparing such microanatomical aspects as hydroxyapatite density and patterns of tissue break-down in the nasal capsule walls, as well as bone remodelling activity in recesses and nascent sinuses. Microscopic examination of bone cells along the osseous boundaries of the sinuses/recesses will reveal the pattern of activity of bone removal (by osteoclasts) and bone deposition (by osteoblasts). Immunohistochemical methods with add greater scrutiny of osteoclast activity by identifying binding sites on bone as well as osteoclast precursor cells. This research tests the hypothesis that paranasal sinuses form via an invasive developmental trajectory that is distinct from routine bone remodeling.The researchers aim to draw a firm distinction between paranasal sinuses and recesses, and to more clearly understand the process which forms a "true" sinus - pneumatization. This research will contribute to the intellectual development of a graduate student, who will have the opportunity to assist in nearly every phase of the project. A digital archive of histological images from the specimens will be created and made available on the internet, providing a resource for other investigators of facial anatomy and ontogeny. The results of this research will serve as foundational knowledge to inform future work. Such information is needed to allow unambiguous identification of sinuses in any species, which will provide a firmer foundation for comparative CT studies and clinical research into sinus pathology. For example, the use of these spaces as phylogenetically important traits and the full understanding of certain congenital abnormalities of the facial skeleton (e.g., sinus absence and other abnormalities) hinge on a clear understanding of how sinuses form.

最近使用计算机断层扫描（CT）来研究鼻窦，导致重新关注这些粘膜衬里的颅腔的系统发育意义和功能。然而，通过CT识别鼻窦很复杂，因为即使是缺乏真正鼻窦的哺乳动物也有可能被误认为是鼻窦的鼻腔凹陷区域（称为凹陷）。差异是发展性的;这些凹陷仅仅是软骨性鼻囊骨化的产物，而真正的鼻窦是通过一种称为骨化的过程形成的，在该过程中，骨（和可能的软骨）被特殊细胞（破骨细胞）主动去除。 迄今为止，没有研究记录了这些不同过程的组织学和细胞特征，这些不同过程导致物种之间的颅骨形状非常不同，并且很可能是哺乳动物物种（包括人类）中具有临床重要性的发育异常的基础。在这个项目中，研究人员将确定在非人类灵长类动物中形成可识别的鼻旁窦的空间与可比的纳塔尔凹陷之间是否存在微观差异。 他们将研究灵长类动物的尸体新生儿，这些灵长类动物有和没有发育上颌骨和/或额窦，比较微观解剖学方面，如羟基磷灰石密度和鼻囊壁组织分解的模式，以及凹部和新生窦中的骨重建活动。 沿窦/隐窝的骨边界沿着骨细胞的显微镜检查将揭示骨去除（通过破骨细胞）和骨沉积（通过成骨细胞）的活动模式。免疫组织化学方法通过鉴定骨上的结合位点以及破骨细胞前体细胞来增加破骨细胞活性的更详细的检查。这项研究验证了一个假设，即鼻窦是通过一种不同于常规骨重建的侵入性发育轨迹形成的。研究人员的目标是明确区分鼻窦和隐窝，并更清楚地了解形成“真正”鼻窦炎的过程。这项研究将有助于研究生的智力发展，他们将有机会在项目的几乎每个阶段提供帮助。将创建标本组织学图像的数字档案，并在互联网上提供，为面部解剖学和个体发育学的其他研究人员提供资源。这项研究的结果将作为基础知识，为未来的工作提供信息。需要这些信息来明确识别任何物种的鼻窦，这将为鼻窦病理学的比较CT研究和临床研究提供更坚实的基础。例如，使用这些空间作为遗传学上重要的特征，并充分了解面部骨骼的某些先天性异常（例如，鼻窦缺失和其他异常）取决于对鼻窦如何形成的清楚理解。