Trichilemmal cysts, also known as pilar cysts, are slow-growing lesions commonly found on the scalp of elderly women. They arise from outer root sheath epithelium and have a distinctive pattern of keratinization called trichilemmal keratinization. Here, we describe a rare case of a trichilemmal cyst on the lower lip mucosa of a 29-year-old man. The infrequency of intraoral hairs unquestionably ...

This study was carried out on the vaginal epithelium of eight Awassi ewes during estrus and luteal phases in order to evaluate the histological effect of vitamin A on the vaginal epithelium, vaginal smears were taken and stained by methylene blue. Light microscope was used in examination of slides. The present result revealed that vitamin A stimulated the process of keratinization which in turn...

Keratins are the characteristic structural proteins of the highly cornified epidermis of the skin, feathers, and hoof. Keratin proteins provide the structural basis for the unique properties of the biomaterial horn and its protective function against a wide range of environmental factors. Hoof horn is produced through a complex process of differentiation (keratinization) of epidermal cells. For...

There are available results of electron microscopic studies as. regards the oral mucosa by such researchers as Sognnaes and Albright (1956, 1958), Themann (1958), Fasske and Themann (1959), Frenkel (1959), Albright (1960), Rhodin and R eith (1962) and Arai (1961, 1962). But all of them fail to give a description of the epithelium of the tongue, and only Rhodin and R e i t h give a brief mention...

Artificial skin or skin equivalents have been used for clinical purpose to skin graft and as substitutes for animal experiments. The culture of cell lines such as HaCaT has the potential to produce large amounts of artificial skin at a low cost. However, there is a limit to keratinization due to the restriction of differentiation in HaCaT. In this study, a culture device that mimics the in vivo...

Keratinized mucosa is of fundamental importance to maintain healthy gingival tissue, and understanding the mechanisms of oral mucosa keratinization is crucial to successfully manage healthy gingiva. Previous studies have shown a strong involvement of the basement membrane in the proliferation and differentiation of epithelial cells. Therefore, first, to identify the keratinized mucosa-specific ...

Several reports have suggested that mesenchymal glycosaminoglycans (GAG) may be involved in the regulatory role of epithelial differentiation. Some researchers have pointed out that exogenous GAG affects extracellular GAG accumulation. We have therefore examined the effect of added GAG on two typical processes of avian skin differentiation: keratinization and feather formation. Glycosaminoglyca...

Leukoplakias are oral lesions that may have many clinical and histological aspects and they are usually associated with malignancy when dysplastic alterations are shown. However, these transformations may occur in non-dysplastic lesions that show harmless clinical aspect. For this reason, the proposal was to study the p53 and PCNA immunohistochemical expression in non-dysplastic leukoplakias, t...