Lingual adaptations of the Tarentola annularis with new insights into its papillary system adaptations: Ultrastructure, histochemistry, and immunohistochemical observations.

Our research aims to conduct a comprehensive ultrastructural, histochemical, and immunohistochemical examination of Tarentola annularis' tongue, utilizing various techniques such as light, scanning electron microscopy, and morphometric analysis. The complex papillary system consisted of four conical subtypes and one filiform type. The apex carried three conical subtypes (elongated, quadrilateral, and round); the midtongue carried two papillary types (quadrilateral conical and rectangular pointed filiform); and the hindtongue carried two conical subtypes (quadrilateral and elongated serrated). The dorsal papillary surface carried little taste pores on the foretongue and taste buds on the midtongue. The foretongue had a slightly stratum corneum that spread to coat the papillae, while the mid- and hindtongue did not. The glands are absent from the foretongue but are found in the interpapillary spaces of the mid- and hindtongue. Histochemical analysis reveals the presence of collagen fibers in the muscle bundles and the papillary core. The midtongue glands exhibited a strong reaction to AB and PAS, while the hindtongue showed moderate AB positivity and strong positive PAS. The cytokeratin expression in the foretongue papilla was positive, whereas the papillae in other regions were negative. The Tarentola annularis exhibits distinctive lingual structural characteristics due to its varied feeding habits influenced by available food particles.

Gross, ultrastructural, and histological characterizations of pecten oculi of the glossy ibis (Plegadis falcinellus): New insights into its scanning electron microscope-energy dispersive X-ray analysis.

The current study shows the first attempts to clarify the gross, ultrastructure, and histological properties of the pecten oculi of the diurnal, visually active glossy ibis, as well as scanning electron microscope-energy dispersive X-ray (SEM-EDX) image analysis (Plegadis falcinellus). The pecten oculi was found on the eyeball's posteroinferior wall, adjacent to the optic nerve in both the craniocaudal and posterio-anterior directions. The plicated quadrilateral black pigmented pecten oculi consisted of a base, 10-12 pleats, and an apex. The base was joined by an elevated ridge and derived from the non-vascular retina, while the apex was not a fused part and was found neighboring the gelatinous vitreous body. The limited interpleat spaces were somewhat wider at the base of the pecten oculi. The outer surface of each highly vascular pecten pleat revealed a tortious coiled formation due to the existence of a considerable number of capillary vessels. The outer pleat surfaces had a vitreopecteneal limiting membrane that segregated the pecten pleats from the vitreous body. The high SEM magnification revealed that there are considerable plentiful hyalocyte cells on the outer surface of the pleats. The SEM-EDX analysis of the elementary formatting of the pecten oculi (at apex, middle, and base) clarified that the carbon represents the highest and a half percent. Furthermore, oxygen represents one-third of all elemental composition in the three regions, while the lowest percentage is calcium. Finally, the pecten oculi characterizations of this migratory bird on the Northern Egyptian shore were associated with their adaptive dietary strategies.

Lingual papillary system of the Egyptian mouse-tailed bat (Rhinopoma hardwickii): New insights to its feeding strategies using scanning electron microscope, and immunohistochemical analysis of keratin.

The current investigation described the ultrastructural and histological features of the lingual papillary system in 14 adult Rhinopoma hardwickii using scanning electron and light microscopy, and immunohistochemical staining of keratin. Three types of lingual papillae were recognized; one filiform mechanical and two gustatory (fungiform and circumvallate) of three directions: posterior, posteromedian, and median. Five filiform papillae subtypes were observed in four regions. The lingual tip had numerous giant filiform papillae. The lingual root was divided into two regions, an anterior papillary and a posterior non-papillary region that had only three circumvallate papillae in a triangular pattern. Histologically, the papillae exhibited detached thick keratin that spread over the dorsal epithelial surface. The dorsal surface of the root had stratified keratinized circumvallate papillae. Concerning the pan-cytokeratin (CK) antibody staining, moderate CK expression was observed in the superficial corneal layer of the apical lingual mucosa. While the superficial corneal cell layer in both body and root exhibited increasing of CK antibody. Morphometrically, there was a significantly increased, region-specific number of triangular, pointed filiform papillae, which were relatively increased in length and width. However, the round conical blunt filiform papillae and fungiform papillae were sparse. We concluded that our results showed distinguished adaptations in the lingual structure and its different papillae established on the nutritional and energetic demand of this bat species. This lingual adaptation is summarized in number, position, taste buds, direction, ultrastructural features, and histological that concerned with its ability in eating during the night flight. RESEARCH HIGHLIGHTS: Three types of lingual papillae; one mechanical (filiform) and two gustatory (fungiform and circumvallate) in which there were three circumvallate papillae on the posterior part of the lingual root in a triangular arrangement with an irregular surface, but the filiform papillae had five subtypes arranged in four regions. The lingual root was divided into two regions, an anterior papillary region and a posterior non-papillary region that only had three circumvallate papillae. Concerning staining with a pan-cytokeratin (CK) antibody, moderate CK expression was observed in the superficial corneal layer of the lingual mucosa of the tongue apex while the superficial corneal cell layer of the body and root exhibited increased expression of the CK antibody compared to the lingual apex.

A histological and immunohistochemical study on the parabronchial epithelium of the domestic fowl's (Gallus gallus domesticus) lung with special reference to its scanning and transmission electron microscopic characteristics.

The current study was designed to give complete histo-and immunohistochemical features of the parabronchial epithelium of domestic fowl's (Gallus gallus domesticus) lung with special reference to Scanning electron microscope (SEM) and mean transmission electron microscope (TEM) features. The lung exhibited variable-sized atrial openings encircled by exchange tissue zones. The parabronchial atrial chambers appeared as ovoid and polygonal-shaped that separated by the well-developed interatrial septum. The deep atrial lumens had blood vessels pierced by openings that represent the infundibula. The parabronchial blood capillaries meshwork was branched and exhibited ovoid-shaped air capillaries with numerous extravasated blood vessels. By TEM, there were several air capillaries and groups of squamous and endothelial respiratory cells and the squamous cells had oval nucleus with evenly distributed chromatin. The endothelial respiratory cells had few microvilli on their free surfaces. The parabronchial tubes opened into a group of widened atria that had smooth muscle bundles at the interatrial septa. The atrial chambers led to narrow infundibula. Moreover, the lining epithelium of parabronchi, atria, infundibula, and air capillaries was formed by simple squamous epithelium. Air capillary walls were lined by two types of respiratory cells (Types-I and II). Collagen fibers were concentrated within the tunica externa layers of the parabronchial blood vessels as well as, they were observed in CT interparabronchial septa. Immunohistochemically, the elastin immunoreactivity was detected around the parabronchial blood vessels, at the base of each parabronchial atria, and in the area encircling the alveolar-capillary walls. Our work concluded that there are a relation between the fowl's lifestyle and the surrounding environmental conditions.