Brainstem Mechanisms of Gustation
Robert H. Cagan in Neural Mechanisms in Taste, 2020
In mammals, taste buds are entirely internal, although they are distributed widely throughout the oropharyngeal cavity. The distribution of taste buds has been studied in a number of mammalian species, including humans,12 and has recently been completely characterized in the hamster.13 Taste buds on the anterior two thirds of the hamster tongue are located in fungiform papillae; those on the posterior one third, in foliate papillae on the sides of the tongue and a single vallate papilla along the midline. There are also taste buds on the soft palate, in the nasoincisor ducts and nasopharynx, on the laryngeal surface of the epiglottis, in the esophagus, on the buccal walls, and in the sublingual organ. There are a total of 723 taste buds in the hamster, of which 18% are located in the fungiform papillae, 23% in the single vallate papilla, 32% in the foliate papillae, 14% on the soft palate and nasoincisor ducts, 10% on the epiglottis and surrounding area, and 3% in the remaining locations.13 Similar distributions are seen in the rat14 and other mammalian species that have been studied.
Head and Neck
Rui Diogo, Drew M. Noden, Christopher M. Smith, Julia Molnar, Julia C. Boughner, Claudia Barrocas, Joana Bruno in Understanding Human Anatomy and Pathology, 2018
As explained in Section 3.4.4.2, the tongue is a peculiar structure of the adult head, both developmentally and evolutionarily, because its muscles actually derive from the somites. To form the tongue, trunk mesodermal myocytes migrated around and beneath the pharynx and then rostrally to the oral region. Correspondingly, in humans these muscles are innervated by the hypoglossal nerve (CN XII) and by C1 (which runs with the hypo-glossal nerve to innervate the geniohyoid muscle). The tongue includes the root of the tongue (posterior one-third), the body of the tongue (anterior two-thirds), and the apex of the tongue; these regions and the dorsum of the tongue are shown in Plate 3.40. The dorsum of the tongue includes the foramen cecum lying in the midline at the point of the terminal sulcus (sulcus terminalis); this foramen marks the origin of the thyroglossal duct, formed by the caudal migration of the embryonic thyroid gland from an invagination of the tongue epithelium. Anterior to the terminal sulcus, the dorsum of the tongue is covered with lingual papillae (vallate, filiform, fungiform, and foliate) and is divided in the midline by the median sulcus. Posterior to the terminal sulcus lies the lingual tonsil. The median glossoepiglottic fold is a midline mucosal fold connecting the dorsum of the tongue to the epiglottis and lying medial to the lateral glossoepiglottic folds; the depressions between the median and lateral glossoepiglottic folds are the epiglottic valleculae.
ExperimentaL Oral Medicine
Samuel Dreizen, Barnet M. Levy in Handbook of Experimental Stomatology, 2020
Cavitation was produced in the enamel and dentin of the mandibular incisors. Adjacent to the cavitation, normal appearing enamel was replaced by a chalky white, amorphous substance in the 35-J animals and by a smooth, glassy substance in the 55-J animals. Initially, there was a small reddish brown lesion at the site of the tongue exposed to 35 J. After 3 days, a sharply demarcated large ulcer was manifest. Adjacent mucosa was erythematous and edematous. In hamsters given 55 J, the ulcerated area on the tongue was deeper, with greater reddening and swelling of the adjacent mucosa at 3 days than in those given the lower dose. Lingual papillae were flattened, and the entire tongue was enlarged and swollen. At 7 days, the tongue was still edematous, and healing was less advanced than in animals given the lower exposure. Microscopically, the tongue ulcers had the typical pattern of nonspecific ulceration, with acute purulent inflammation. Evidence of granulation tissue formation and epithelialization was present at 7 days. Tongues exposed to 55 J showed disruption of muscle bundles and destruction of striated muscle tissue. Epithelium was thin and papillae were atrophied. The dental pulps of the irradiated incisors had severe degenerative changes. Less severe pulpal degeneration was evident in the molar teeth located at some distance from the laser focal point.
Oral microbial diversity analysis among atrophic glossitis patients and healthy individuals
Published in Journal of Oral Microbiology, 2021
Hong Li, Jing Sun, Xiaoyan Wang, Jing Shi
The study population is consisted of 76 women and 24 men with 40 years or older from Shanxi Provincial Peoples Hospital. The oral microbiome in 50 participants with atrophic glossitis and 50 healthy participants was characterized. For the atrophic glossitis subjects, their lingual papillae on the dorsum of the tongue decreased by more than 50%, and long-term areas of damage with pain persisted more than 2 months; none used any broad-spectrum antibiotics or antifungal medicine for nearly 2 weeks. None of the patients used glucocorticoids or immunosuppressants within the 3 months, and there was no tumour recurrence. All participants provided written informed consent for all study procedures, including questionnaires and saliva sample collection. Written informed consent was obtained from the all participants and ethical approval for the study was obtained from the Ethics Committee of Shanxi Provincial People’s Hospital (No-51).
In vivo antifungal activities of farnesol combined with antifungal drugs against murine oral mucosal candidiasis
Published in Biofouling, 2021
Chengxi Li, Zheng Xu, Siqi Liu, Yun Huang, Wei Duan, Xin Wei
Histopathological examination showed that itraconazole alone decreased the number of hyphae on the epithelium of tongues of infected mice (Figure 3C1, C2), but much greater fungal clearance and normal lingual papillae were evidently observed in mice treated with the combination of 0.16 mg kg−1 itraconazole and farnesol at 4 μM or 8 μM (Figure 3C3–C5).
Comparative studies on the tongue of the Egyptian fruit bat (Rousettus aegyptiacus) and the common quail (Coturnix coturnix)
Published in Egyptian Journal of Basic and Applied Sciences, 2023
Amany Attaallah, Yousra Fouda, Abd El-Fattah B. M. El-Beltagy, Amira M. B. Saleh
Investigation of the tongue of R. aegyptiacus by SEM revealed that there are four types of lingual papillae; filiform, conical, and fungiform and circumvallate (Figure 3a-f). These papillae differ in shape, size, number, distribution and orientation in relation to feeding habits and nature of food.
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