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Homo Sapiens (“Us”): Strengths and Weaknesses
Published in Michael Hehenberger, Zhi Xia, Huanming Yang, Our Animal Connection, 2020
Michael Hehenberger, Zhi Xia, Huanming Yang
Smell or olfaction is a “chemical” sense, just as “taste.” In 1991, Richard Axel and Linda Buck50 discovered that hundreds of genes in our DNA are coding for the odorant sensors located in the olfactory sensory neurons in our noses. When an odorant attaches itself to the receptor, it triggers a protein change and an associated electric signal to be sent to the brain. Smells are composed of a large number of different substances and we interpret the varying signals from our receptors as specific scents. Odor molecules possess a variety of features and, thus, excite specific receptors more or less strongly. This combination of excitatory signals from different receptors makes up what we perceive as the molecule’s “smell.” In the brain, olfaction is processed by the olfactory system. Olfactory receptor neurons in the nose differ from most other neurons in that they die and regenerate on a regular basis. Figure 4.12 shows the peripheral olfactory system, which consists mainly of the nostrils, ethmoid bone, nasal cavity, and the olfactory epithelium, characterized by layers of thin tissue (covered in mucus) that line the nasal cavity. The layers of epithelial tissue include the mucous membranes, olfactory glands, olfactory neurons, and nerve fibers of the olfactory nerves.
Homo Sapiens (“Us”): Strengths and Weaknesses
Published in Michael Hehenberger, Zhi Xia, Our Animal Connection, 2019
Smell or olfaction is a “chemical” sense, just as “taste.” In 1991, Richard Axel and Linda Buck50 discovered that hundreds of genes in our DNA are coding for the odorant sensors located in the olfactory sensory neurons in our noses. When an odorant attaches itself to the receptor, it triggers a protein change and an associated electric signal to be sent to the brain. Smells are composed of a large number of different substances and we interpret the varying signals from our receptors as specific scents. Odor molecules possess a variety of features and, thus, excite specific receptors more or less strongly. This combination of excitatory signals from different receptors makes up what we perceive as the molecule’s “smell.” In the brain, olfaction is processed by the olfactory system. Olfactory receptor neurons in the nose differ from most other neurons in that they die and regenerate on a regular basis. Figure 4.12 shows the peripheral olfactory system, which consists mainly of the nostrils, ethmoid bone, nasal cavity, and the olfactory epithelium, characterized by layers of thin tissue (covered in mucus) that line the nasal cavity. The layers of epithelial tissue include the mucous membranes, olfactory glands, olfactory neurons, and nerve fibers of the olfactory nerves.
Nanostructured Drug Carriers for Nose-to-Brain Drug Delivery
Published in Yasser Shahzad, Syed A.A. Rizvi, Abid Mehmood Yousaf, Talib Hussain, Drug Delivery Using Nanomaterials, 2022
Talita Nascimento da Silva, Emanuelle Vasconcellos de Lima, Anna Lecticia Martinez Martinez Toledo, Julia H. Clarke, Thaís Nogueira Barradas
The olfactory region plays the most important part in drug transportation to the CNS, since the olfactory neurons reach the olfactory bulb via the cribriform plate of the ethmoid bone, enabling transportation along such neurons (Wu, Hu, and Jiang 2008). The potential intranasal limitations include the small nasal cavity volume combined with the drug's short residence time and the poor paracellular drug transportation through olfactory epithelium (Sonvico et al., 2018).
In-situ tensile test under microtomography to characterize mechanical behavior of ethmoid bone: a preliminary study
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2020
V. Serantoni, N. Faraj, G. Subsol, E. Rondet, L. Ollier, G. Captier, F. Jourdan, V. Favier
Mechanical properties of the ethmoid bone are not well understood due to its complex geometry (referred as a ‘labyrinth’), and its deep location in the skull base. However, it is of particular interest for surgeons to appraise the force range they can apply during endoscopic procedures and know what kind of haptic feedback should be produced by a simulation device in order to be realistic for trainees (Favier et al. 2019). Ethmoid bone lamellae have a mainly cortical structure (Berger et al. 2013) which has no equivalent in the human body. The aim of this study was to describe a protocol of in-situ tensile test under microtomography (micro-CT) to characterize ethmoid bone behavior.