FOM 6.2.3 Flashcards
What are each of these on the histological slide?
Epidermis
Dermis
Hypodermis
What are the cell types in the epidermis?
Keratinocytes - epidermal skin cells
Merkel cells - tactile receptors
Langerhans cells - macrophages
Melanocytes - derived from neural crest cells
What are each of these cell layers?
Top to bottom
Stratum corneum, lucidium, granulosum, spinosum, and basale
What is the underlying etiology of psoriasis?
Infiltrating immune cells synthesize and release cytokines that signa; proliferation and thus lead to a reduced length of cell cycle. Turnover is reduced to three to four days.
Answer the following
D - Cytokines from infiltrating lymphocytes
What is filaggrin?
It induces the aggregation of keratins
What is are lamellar bodies?
The place where lipids form
The formation of the water barrier is cause by what?
What is lamellar ichthyosis caused by?
A mutation in the TGM 1 gene which leads to a defective transglutaminase protein.
What would you find in dermatitis herpetiformis?
Autoantibodies to transglutaminase, a gluten intolerance and IgA deposits
What is a melanocyte?
It originates from the neural crest and it creates melanosome that travel to the nearby keratinocyte.
What is a langerhans cell?
It is a peripheral dendritic cell that presents antigens to the immune complex.
What is a merkel cell?
These are tactile mechanoreceptors that associate with the basal lamina. It has a short axon
What is the target antigen of pemphigus vulgaris?
The target antigen for pemphigus vulgaris is desmoglein (DSG) 3
Pemphigus foliacues has autoantibodies to what?
DSG1
Moving from the base to surface what is happening to the level of DSG3? DSG1?
The levels of Dsg3 is decreasing moving from base to top
The levels of Dsg1 is increasing from the base to the top
What are the two types of pemphigus vulgaris?
Musous membrane dominant - anti DSG-3
Mucocutanous - anti-DSG 1 and DSG 3
What is the levels of Dsg1 in the mucous membrane?
It is almost non existant
This histological slide is indicative of what disease?
This is pemphigus vulgaris. The mucosal epithelial damage is more severe owing to a lack of compensation by the weakly expressed DSG-1.
Mucocutaneous pemphigus vulgaris has autoantibodies against what?
It has autoantibodies for Dsg1 and Dsg3
What is this a picture of
Pemphigus foliaceus anti-DSG1 antibodies produce blister formation in the upper epidermis, because the remaining DSG3 can maintain cell–cell adhesion in the lower epidermis; there are no blister formations on the mucous membranes, because the remaining DSG3 can completely maintain cell–cell adhesion of the mucosal epithelium
What are the main characterics to know about the hair follicle?
The external root sheath is continuous with the stratum basale
The internal root sheath surrounds the hair shaft
Depmal papilae are a reservoir of stem cells
What are the three “gen” terms associated with hair growth and what do they mean?
Anagen - growth phase
Catagen - intermediate/regression
Telogen - rest/shedding
What is the type of secretion that sebaceous glands go through?
Holocrine secretion
What are the two types of secretion sweat glads do?
There are two general types, eccrine and apocrine. Eccrine (merocrine) sweat glands are long tubular extensions from the epidermis which coil into a ball-shaped mass in the dermis or hypodermis. Apocrine glands are in the axilla, perianal and pubic areas, scrotum, labia majora and around the nipples. They lie in the subcutaneous tissue and their ducts terminate in hair follicles.
What is the meissner and pacinian corpuscle?
Meissner - tactile receptor
Paninian - sensitive to pressure
Compare first and second intention healing
First intention healing involves clotting, neutrophils, monocytes, macrophages,
and fibroblasts and vascular endothelial cells
Second intention - fibroblasts are myofibroblasts
What are the two types of mechanisms for tissue repair in the skin?
Mechanisms of tissue repair: regeneration and scar formation. Following mild injury, which damages the epithelium but not the underlying tissue, resolution occurs by regeneration, but after more severe injury with damage to the connective tissue, repair is by scar formation
What is the basis of skin grafting?
Take a piece of skin for somewhere else, put a bunch of little tiny holes in it and put it somewhere else. It can also depend on the thickness of tissue needed. Thick skin vs thin skin.
What is the importance of the stratum basale?
It is the source of the stem cells after injury to the skin
