skin Flashcards
what are the 4 skin layers
Stratum basale (basal layer)
Stratum spinosum (spinous layer)
Stratum granulosum (granular layer)
Stratum corneum (cornified layer)
what is wrong with this poor baby and what is the prognosis
Epidermolysis Bullosa
poor
what compound is turned in to pre-D3 by sunlight
7-dyhydrocholesterol
90% of skin are what cell type
keratinocytes
which is the layer only in thicker skin and where is it in the layrs
stratum lucidum
directly under stratum corneum
what
descrobe
keratinocytes - cobblestone appearance
what is the size of 1 keratin filament
10nm
how do keratin fibres line up
one acidic goes with one basic
how are basal skin cells attached to the BM
hemidesmosomes
when is teh only time skin cells can proliferate
when attached to the BM
Epidermis bullosa is caused by mutations to
laminin332, collagen VI, collagen VII
how do desmosome junctions work - what proteins
cadherins
which layer of skin has desmosomal jncts
spinosum
which proteins are expressed in the stratum granulosum
Filaggrin, Involucrin, Loricrin
corneocytes are held together by corneodesmosomes. what is between them
ceramides (intercellular lipids)
where do you find tight jncts in the skin
just under the corneum
what are the 2 layers of dermis
papillary
reticular
main type of sell in dermis
fibroblast
papillary dermis is mostly
type 3 collagen and elastin
reticular dermis is mostly
type 1 collagen
what is the difference between hair and fur
hair is sensory whereas a lot of fur has no innervation
where do stem cells of the hair follicle live
bulge region
which specific keratin expressed by hair follicles
15
what are the 3 fases of hair growth
Anagen-active
Catagen-regressive
Telogen-resting
main fnct of eccrine sweat glands
thermoregulations
appocrine glands are attached to the
hair follicle
what is the brown melanin called
eumelanin
what is the red melanin called
pheomelanin
what are langerhans cell in skin (4)
Specialised tissue-resident macrophage
Self maintain
Basal and spinous layers
First line of defence
Presents antigen to T lymphocytes
where are Merkel cells
stratum basale
first cells in proliferative phase of skin injury
fibroblasts
fibroblasts secrete what in wound healing
type 3 collagen
after vasoconstriction and fibrin clot, what happens in inflammation phase of wound healing
Blood vessel dilation
Neutrophils then macrophages are recruited by Ils and TNF etc
when is a chronic wound
non-healing >6wk
what are these two layers of the dermis
papillary (top)
reticular (underneath)
skin infection is usually
staph aureus
hot tub acquired folliculitis bacterium
pseudonomas aeruginosa
usual bacterium folliculitis
staph aureus
tx folliculitis
oral abx
impetigo
tx impetigo
topical or oral abx
1% hydrogen peroxide cream if serious
where is cellulitis
dermis AND hypodermal fat
what is this? what bacteria
erisypelas
only dermis
strep pyogenes
what is the moa of scalded skin syndrome in babies
exotoxins break desmosomes between keratinocytes
what does scalded skin syndrome look like and what tx
very superficial blisters
red baby
rehydration and parenteral abx
verruca tx
topical salicylic acid
what is this
what tx
pityriasis versicolor
anti-fungal shampoo such as ketoconazole
tx scabies
permethrin
ivermectin
which bacteria lyme disease
borrelia
sand fly disease
leishmaniasis
tx leprosy
rifampicin
dapsone
clofazimine
