A blog about dermatology and its related topics. Guide to cope up with dermatology disorders and some dermatology treatments.
Aphthous ulcers (aphthous stomatitis) and herpes simplex infections (herpes labialis) account for approximately 95% of all oral ulcers. Both are often termed “cold sores” by the public, but separation is desirable and important. Aphthous ulcers occur entirely within the mouth. Often, only a single ulcer is present, but even when there are multiple ulcers present, [...]
Hair follicles are composed primarily of epidermally derived cells. Early in embryogenesis, clusters of pluripotential epidermal cells “bud” down from the basal layer and extend into the dermis where they form the hair follicle. A cup-shaped indentatjon at the base of the epidermal bud accepts a specialized dermal papilla with its contribution of blood vessels. [...]
Langerhans’ cells account for 3% to 5% of the cells in the epidermis. They are dendritic cells and thus superficially resemble melanocytes. They do not, however, produce pigment, and they possess cell surface markers that identify them as being of monocyte-macrophage lineage. They originate in the bone marrow and from there move in and out [...]
Most often, urticaria, erythema multiforme, erythema nodosum, and lcukocytoclastic vasculitis develop as a result of immunologic reactions to antigens. For example, when erythema multiforme occurs as a result of herpes simplex infection, the eruption is due to the antigenic rather than infective properties of the virus. Thus, the herpes simplex virus can cause vesicles of [...]
Keratinocytes account for 95% of the cells of the epidermis. These cells are mainly responsible for the production of the family of fibrillar proteins known as keratins, but other proteins and sterols are, to a lesser degree, also synthesized. Keratinocytes begin their life as germinative, undifferentiated cells at the dermal-epidermal junction. These cells are termed [...]
Fingernails and toenails can, in a way, be viewed as arising from a “follicle” analogous to that of the hair follicle . The orientation of this “follicle,” of course, lies parallel rather than vertical to the surface of the skin.The nail matrix from which the nail plate grows lies deep to the posterior nail fold. [...]
Fibroblasts are mesenchymal, spindle-shaped cells responsible for the synthesis of the collagen, reticulin, and elastic fibers of the dermis. The initial construction of all three of these fibers occurs within the fibroblast, but posttranslational modification of each of them occurs extracellularly when enzymes clip the terminal portions from the fibrillar molecules. Elastic fibers are branched [...]