More Like this

1. The effect of nasal airway obstruction on the dispersion and deposition of inhaled volatile droplets in the human nasal cavity: A numerical study

   https://doi.org/10.1016/j.jaerosci.2020.105650  

   Tohidi, R.; Sajadi, B.; Ahmadi, G. (December 2020, Journal of Aerosol Science)

   null (Ed.)
2. The evolution of nasal immune systems in vertebrates

   https://doi.org/10.1016/j.molimm.2015.09.008  

   Sepahi, Ali; Salinas, Irene (January 2016, Molecular Immunology)
3. The nasal cavity in agoutis (Dasyprocta spp.): a micro-computed tomographic and histological study

   https://doi.org/10.3897/vz.72.e76047  

   Smith, Timothy D.; Bonar, Christopher J. (February 2022, Vertebrate Zoology)

   Abstract Nasal anatomy in rodents is well-studied, but most current knowledge is based on small-bodied muroid species. Nasal anatomy and histology of hystricognaths, the largest living rodents, remains poorly understood. Here, we describe the nasal cavity of agoutis ( Dasyprocta spp.), the first large-bodied South American rodents to be studied histologically throughout the nasal cavity. Two adult agoutis were studied using microcomputed tomography, and in one of these, half the snout was serially sectioned and stained for microscopic study. Certain features are notable in Dasyprocta . The frontal recess has five turbinals within it, the most in this space compared to other rodents that have been studied. The nasoturbinal is particularly large in dorsoventral and rostrocaudal dimensions and is entirely non-olfactory in function, in apparent contrast to known muroids. Whether this relates solely to body size scaling or perhaps also relates to directing airflow or conditioning inspired air requires further study. In addition, olfactory epithelium appears more restricted to the olfactory and frontal recesses compared to muroids. At the same time, the rostral tips of the olfactory turbinals bear at least some non-olfactory epithelium. The findings of this study support the hypothesis that turbinals are multifunctional structures, indicating investigators should use caution when categorizing turbinals as specialized for one function (e.g., olfaction or respiratory air-conditioning). Caution may be especially appropriate in the case of large-bodied mammals, in which the different scaling characteristics of respiratory and olfactory mucosa result in relative more of the former type as body size increases. 

   more » « less
4. A comparison of diceCT and histology for determination of nasal epithelial type

   https://doi.org/10.7717/peerj.12261  

   Smith, Timothy D.; Corbin, Hayley M.; King, Scot E.; Bhatnagar, Kunwar P.; DeLeon, Valerie B. (January 2021, PeerJ)

   Diffusible iodine-based contrast-enhanced computed tomography (diceCT) has emerged as a viable tool for discriminating soft tissues in serial CT slices, which can then be used for three-dimensional analysis. This technique has some potential to supplant histology as a tool for identification of body tissues. Here, we studied the head of an adult fruit bat ( Cynopterus sphinx ) and a late fetal vampire bat ( Desmodus rotundus ) using diceCT and µCT. Subsequently, we decalcified, serially sectioned and stained the same heads. The two CT volumes were rotated so that the sectional plane of the slice series closely matched that of histological sections, yielding the ideal opportunity to relate CT observations to corresponding histology. Olfactory epithelium is typically thicker, on average, than respiratory epithelium in both bats. Thus, one investigator (SK), blind to the histological sections, examined the diceCT slice series for both bats and annotated changes in thickness of epithelium on the first ethmoturbinal (ET I), the roof of the nasal fossa, and the nasal septum. A second trial was conducted with an added criterion: radioopacity of the lamina propria as an indicator of Bowman’s glands. Then, a second investigator (TS) annotated images of matching histological sections based on microscopic observation of epithelial type, and transferred these annotations to matching CT slices. Measurements of slices annotated according to changes in epithelial thickness alone closely track measurements of slices based on histologically-informed annotations; matching histological sections confirm blind annotations were effective based on epithelial thickness alone, except for a patch of unusually thick non-OE, mistaken for OE in one of the specimens. When characteristics of the lamina propria were added in the second trial, the blind annotations excluded the thick non-OE. Moreover, in the fetal bat the use of evidence for Bowman’s glands improved detection of olfactory mucosa, perhaps because the epithelium itself was thin enough at its margins to escape detection. We conclude that diceCT can by itself be highly effective in identifying distribution of OE, especially where observations are confirmed by histology from at least one specimen of the species. Our findings also establish that iodine staining, followed by stain removal, does not interfere with subsequent histological staining of the same specimen. 

   more » « less
5. Metabolic demands and sexual dimorphism in human nasal morphology: A test of the respiratory‐energetics hypothesis

   https://doi.org/10.1002/ajpa.24692  

   Kelly, Alexa Pennavaria; Ocobock, Cara; Butaric, Lauren Nicole; Maddux, Scott David (January 2023, American Journal of Biological Anthropology)

   Abstract ObjectivesAlthough ecogeographic variation in human nasal morphology is commonly attributed to climatic adaptation, recent research into the “respiratory‐energetics hypothesis” has suggested that metabolic demands for oxygen intake may influence overall nasal size. Here, we further test the respiratory‐energetics hypothesis and investigate potential interactions between metabolic and climatic pressures on human nasal morphology. Materials and MethodsThis study employed computed tomography (CT) scans of 79 mixed‐sex crania derived from an extreme cold‐dry locale (Point Hope, Alaska). In conjunction with basal metabolic rate (BMR, kcal/day) estimates derived from associated femoral head diameter measurements, 41 cranial three‐dimensional (3D) coordinate landmarks and 17 linear measurements were employed in multivariate analyses to test for associations between metabolic demands and nasal/facial morphology across and within the sexes. ResultsOverall nasal size was found to be significantly correlated with BMR both across and within the sexes, with higher metabolic demands predictably associated with larger noses. However, associations between BMR and overall nasal size were found to be predominantly driven by nasal passage height and length dimensions, with the Arctic sample exhibiting minimal (non‐dimorphic) variation in nasal passage breadths. Accordingly, significant correlations between BMR and 3D nasal shape were also identified. DiscussionOur study provides additional support for the respiratory‐energetics hypothesis, while providing insights into potential metabolic and climatic constraints on specific nasal dimensions. In particular, our results suggest that climatic pressures on nasal passage breadths for heat/moisture transfers may necessitate compensatory changes in passage heights (and developmentally‐linked lengths) to maintain sufficient air intake to meet metabolic requirements. 

   more » « less