Chapter 1 Skin

Question 1

From where does apocrine sweat units and sebaceous gland originate?

Answer 1

Apocrine frim upper follicular epithelium

Sebaceous from midregion of follicle

Question 2

What is the pattern of merkel cell when with poly and monoclonal keratin 20 staining?

Answer 2

Paranuclear dot

Question 3

Mutation in keratin 5,14 and 1,10 result to?

Answer 3

Epidermolysis bullosa simplex
Epidermolysis keratosis
Respectively

Question 4

What regulates epidermal differentiation?

Answer 4

Histones

Question 5

3 manifestations of abnormal keratinization?

Answer 5

Parakeratosis (retained nuclei) 
Corps ronds (rounds, clear to pink abN keratinized cells)
Grains (elongated, basophilic, abN keratinized)

Question 6

What are the phases of keratinization?

Answer 6

Synthetic

Degradative

Question 7

What are responsible for desmosomal adhesion?

Answer 7

Cadherins

Desmogleins and desmocollins (Calcium dep)

Question 8

Responsible for keratin filament aggregation

Answer 8

Filaggrin

Question 9

Melanocyte:keratinocyte ratio?

Answer 9

1:10

Question 10

Appearance of melanocyte in H&E stain?

Answer 10

Cell with ample amphophilic cytoplasm or as a clear cell in the basal layer of epidermis

Question 11

Where are melanosomes produced?

Answer 11

Golgi bodies

Question 12

Reason for red head?

Answer 12

LOF mutation in melanocortin 1 receptor (MC1R) –> eumelanin to pheomelanin

Question 13

Reason for vitiligo and albinism?

Answer 13

Vitiligo - destruction of melanocyte

Albinism - N # of melanocyte, unable to fully pigmented melanosomes

Question 14

Layer of epidermis where langerhan cells are found?

Answer 14

Spinosum

Question 15

Stain for langerhans? How do they appear?

Answer 15

Gold chloride, CD1 alpha, S-100

Dendritic cells in sections, with folded nucleus and distinct intracytomplasmic organelles and birbeck granules

Question 16

Where does langerhans originate

Answer 16

Bone marrow

Monocyte-macrophage lineage

Question 17

Function of langerhans

Answer 17

In the afferent limb of immune response by providing for recog, uptake,processing and presentation of antigens to sensitized T lympho; impt in induction of delayed type hypersensitivity

Question 18

Components of dermoepidermal junction

Answer 18

Plasma membranes of basal cells with hemidesmosomes; lamina lucida; lamina densa (basal lamina); fibrous comp (anchoring fibrils, dermal microfibrils, collagen)

Question 19

2 major hemidesmosomal proteins

Answer 19

BP230 bullous pemphi antigen 1

BP180 bullous pemphi ant 2, type XVII collagen

Question 20

Origin of eccrine apocrine glands ducts and pilosebaceous units

Answer 20

Ectodermal

Question 21

What is acrosyringium

Answer 21

Intraepidermal spiral duct opens directly onto skin surface

Question 22

Excretion of sweat is mediated by what innervation

Answer 22

Cholinergic (biphasic)

Question 23

Decapitation secretion can be found in?

Answer 23

Apocrine glands

Question 24

Apocrine secretion mediated by?

Answer 24

Adrenergic and circulating catecholamines

Question 25

Sites of apocrine glands

Answer 25

Axillae areola anogenital EAC(ceruminous glands) eyelids (glands of moll) stroma of sebaceous nevus of Jadasshon

Question 26

Phases of haur growth

Answer 26

Anagen, active, 3-5y, 85-90%, 0.37mm/day Catagen, involution, 2wks Telogen, resting, 3-5mos

Question 27

What is telogen effluvium

Answer 27

Result of early release from anagen induced by fever surgery weight loss

Question 28

Hair shape partially controlled by what gene

Answer 28

Trichohyalin gene

Question 29

Growth of nail

Answer 29

0.1mm/day, 4-6mos to complete a nail plate | 12-18m for toe nail

Question 30

Infant vs adult dermis

Answer 30

Infant - small collagen bundles staib deep red, many fibroblast Adult - few fibroblast, thick collagen bundles stain pale red

Question 31

2 dermal dendritic cells in adult dermis

Answer 31

Factor XIIIa positive | CD34+

Question 32

Major structural protein for the body

Answer 32

Collagen

Question 33

Downregulation of which collagen mrna in photoaging

Answer 33

Coll I and III mrna

Question 34

Type of collagen in BMZ

Answer 34

IV

Question 35

Type of collagen in anchoring fibrils

Answer 35

VII

Question 36

2 components of elastic fibers

Answer 36

Protein filaments | Elastin

Question 37

Ground substance of dermis components

Answer 37

Sulfated acid mucopolysaccharide (chondroitin, dermatan sulfste), neutral mps, electrolytes

Question 38

Minor component of dermis, accumulates in pathologic states

Answer 38

Hyaluronan

Question 39

Vasculature in between papillary and reticular dermis

Answer 39

Subpapillary plexus (postcapillary venules)

Question 40

Vasculature at dermal-subcutaneous interface

Answer 40

Lower horizontal plexus