The Closterium peracerosum-strigosum-littorale (C. psl.) complex is the best characterized charophycean alga with respect to the processes of sexual reproduction. We examined the effect of concanavalin A (Con A) on physiological and ultrastructural changes during the conjugation of the C. psl. complex. Two heterothallic gametangial cells formed a sexual pair as usual; however, the release of ga...

Most fungiform taste buds fail to become innervated when BDNF or NT4 is overexpressed in the basal layer of tongue epithelium. Here, we examined when and how overexpression of BDNF and NT4 disrupt innervation to fungiform papillae. Overexpression of either factor disrupted chorda tympani innervation patterns either before or during the initial innervation of fungiform papillae. NT4 and BDNF ove...

From the 86 species allocated in the genus Rhinella, 25 have their tadpoles described and only R. arenarum, R. chrysophora, R. icterica, R. ornata, R. schneideri and R. spinulosa have aspects of the internal oral morphology evidenced. Herein, the internal oral morphology from 12 species of Rhinella distributed between the morphological groups of R. crucifer, R. granulosa, R. marina and R margar...

Electron microscopy (EM) proved a very helpful means that solved a lot of information in different scientific aspects. EM is a very good tool in the hospitals and research centers. It was aimed to pile up available information on the biology in the descriptive morphology of nematodes and their immature stages by scanning (SEM) and transmission (TEM) electron microscopy. Watson (1965a, b) studie...

A new spirurid nematode, Protospirura canariensis n. sp., a parasite of the black rat Rattus rattus Linnaeus, 1758 (Rodentia: Muridae), in El Hierro Island (Canary Archipelago, Spain), was described by means light (LM) and scanning electron microscopy (SEM). The most discriminating characteristics between species remaining genus were observed to be following: (a) number tooth-like outgrowths su...

Purpose The purpose of this paper is to describe the research results of the morphological structure of white laboratory rats' tongue at the macro-, micro-, and ultrastructural levels by scanning, light, and transmission electron microscopy. Results Our results show that the tongue of these rats has a number of unique morphological features that are different from the tongue of other rodents ...

The tongue of the adult mouse is covered by a multilayered squamous epithelium which is continuous on the ventral surface, however interrupted on the dorsal surface by many filiform and few fungiform papillae. The filiform papillae themselves are subdivided into an anterior and posterior unit exhibiting different forms of keratinization. Thus, the entire epithelium shows a pronounced morphologi...

The volumes of the dermal papilla, matrix and fully grown hair of vibrissal follicles of rats and mice were measured. Dermal papillae were surgically removed from rats' vibrissal follicles and a small new dermal papilla was always reformed. The lower third of rats and mice follicles, containing the whole of the dermal papilla was amputated and very small dermal papillae were reformed. Follicles...

A comparative study was made between sympatric isolates of Schistosoma mansoni: one from a wild rodent (R) Nectomys squamipes and another one from humans (H) isolated from a low endemic schistosomiasis transmission area in Brazil. Our purpose was to detect differences between them concerning chaetotaxy (number and pattern of distribution of the argentophilic papillae) of the cercariae by means ...

Wnt and Shh signaling pathways are critical for the development and maturation of many epithelial tissues. Both pathways have roles in stem cell maintenance, tissue development, and tumorigenesis. However, linkage between these pathways in mammalian systems had not been well established. Here, we report that Shh expression in fungiform papillae and formation of normal mature fungiform papillae ...