derm overview Flashcards
name the innermost layer of the epidermis. What is its function
stratum basalis (basal layer): proliferation center of the epidermis
- in normal skin, cell division above the basal layer is scant or absent
Name the layer of the epidermis above the stratum basalis
stratum spinosum (spinous layer)
Name the epidermal layer that lies above the stratum spinosum
stratum granulosum (granular cell layer)
- acquire lamellar granules
Name the epidermal skin layer that lies the most superficially. What is its function?
stratum Corneum (cornified layer)
- serves as major physical barrier of the skin
How long does it take a cell from the stratum basalis to reach the stratum corneum in normal skin
4 weeks
Type I (immediate) immune process involves what type of immunoglobulins and cell types. What is the response?
- Mast cells and Basophils
- IgE
- hives; bronchospasm; laryngeal edema
Type II (cytotoxic) immune response involves what type of reaction? What immunoglobulins are used
- IgG or IgM react with surface antigen and activate complement
Type III (immune complex) involves what type of immune response? What immunoglobulins are used
antigen-antibody complexes deposited in tissues causing inflammation. Activates complement, increased vascular permeability
- IgG and IgM
Type IV immune response involves what?
- delayed hypersensitivy; usually occurs 24-48 hrs after exposure
- cell mediated immunity
- ex: poison ivy
function of melanocytes
cells found in epidermis: melanin pigment help protect skin against UV radiation
function of langerhan’s cells
found in epidermis
- dendritic cells that have immunologic function; “macrophages of skin;” present antigens to lymphocytes
many blistering diseases arise from defects in what skin layer
basement membrane zone: dermal-epidermal junction
what important structures are contained within the dermis
vessels; nerves; and skin appendages (eccrine, apocrine, and sebaceous glands, hair follicles; nails)
Location and function of eccrine gland
- location: coiled gland dermis; straight duct extends to epidermis
- temperature regulation
function and location (on body) of apocrine glands
- no known function
- bacteria acting on gland secretions leads to body odor
- concentrated in axillary and anogenital regions
- duct drains into midportion of follicle
name the two different types of hair follicles. Give thier description
- vellus hairs: short and fine (forehead)
- terminal hairs: long and think (scalp/axilla)
what is the bulb of a hair follicle
enlargement at base of follicle
superficial fungal infections affect what bodily structure? What type of immune response do they illicit
- affect mucous membranes
- induce cell-mediated immunity
risk factors for developing fungal infections
- moisture
- steroids
- pregnancy
- Abx
scraping the skin away with a curette, a ring shaped instrument
curettage
high frequency current is applied to the lesion, destroying the tissue by drying it out
electrodessication
tissue is destroyed by freezing to -40 C or below using liquid nitogen
cryotherapy
tiny round cookie cutter like tool that is rotated on the surface of the skin until it cuts through all the layers of the skin, including the dermis, epidermis and the upper parts of the subcutis
punch biopsy
seborrheic keratosis: benign or malignant? cause?
- common, benign condition of hyperpigmentation
- due to epidermal hyperplasia
- age related; genetic disposition