Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Basic Science > Andrews > Flashcards

Andrews Flashcards

0
Q

What are langers lines?

A

Also known as cleavage lines. Correspond to natural orientation of collagen fibers in dermis. Are perpendicular to orientation of underlying muscle fibers. Used to obtain most cosmetically appealing surgical scar-surgeon cuts in direction of Langers lines.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

What are lines of

Blaschko?

A

They are skin lines invisible under normal conditions. They follow a V shape over the back, S shape over chest, stomach, sides, and wavy shape over head. Believed to trace migration of embryonic cells (epidermal cell migration)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What diseases are associated with the lines of Blaschko?

A

X-linked dominant-incontinenti pigmenti, CHILD syndrome, focal dermal hypo plasma, MLS syndrome

Inflammatory linear verrucous epidermal naevus, sebaceous naevus, hypomelanosis of Ito, McCune Albright Syndrome, segmental vitiligo

Linear lichen planus, linear cutaneous LE, lichen striatus, linear morphed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What diseases are associated with lines of cleavage?

A

PR, ashy dermatosis, MF, stage 2 syphilis, lesser trelat syndrome, exam thematic kaposi sarcoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the meaning of centrifugal spread?

A

Moving outward from center

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Meaning of centripedal spread?

A

Moving toward center of body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the average thickness of epidermis?

A

O.5mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What types of collagen are present in the dermis?

A

Types 1,3,5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What type of sweat gland is attached to the pilosebaceous unit?

A

Aprocrine glands-coiled duct and straight duct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What type of sweat gland empties onto skin surface?

A

Eccrine gland; Has coiled duct followed by straight duct followed by spiral duct then acrosyringium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the four cell types in the epidermis?

A

Keratinocytes, melanocytes , Langerhans cells, Merkel cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe the Langerhans cell

A

A dendritic cell of the skin and mucosa containing large granules called birbeck granules. They are scattered throughout the epidermis but are often seen in the stratum spinousum
Markers: CD1a***** S100, langerin

Secrete IL12**-this stimulates growth of T cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What happens to the basal cells as they migrate upward towards the epidermis

A

Plasma membrane is replaced with cornfied cell envelope. They flatten and lose nuclei. Extrude cellular contents except for keratin and filaggrin (binds to keratin fibers in epithelial cells; become apart of lipid envelope in stratum corneum, thus playing a role in skin barrier function- blocks UVR and hydrates SC). Filaggrin will also release free amino acids in SC to assist in water retention.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Mutations in filaggrin are associated with what?

A

Ichthyosis vulgaris. Eczema

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where are the stem cell rich sites located in the epidermis

A

Rete ridges and hair bulge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe keratins

A

They make up type 1 and type 2 intermediate filaments, 30 different types, they are paired ( acidic and basic)

Type 1: acidic, K9-20, chromosome 17
Type 2: basic, K1-8, chromosome 12

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What keratins are associated with basal layer?

A

5 & 14.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What keratins are supra basilar?

A

1&10.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are keratohyaline granules?

A

In granular layer. Contain pro filaggrin, keratin and loricrin- hydrophobic protein making up most of CCE

19
Q

What does filaggrin degrade into?

A

Urocanic acid & pyrrolidone carboxylic acid

20
Q

What immune factors do keratinocytes secrete?

A

IL 1. IL 8. TGF B

Express ICAM 1-intercellular adhesion molecule 
MHC class 2
21
Q

What are lamellar granules?

A

Located between granular layer and cornified layer

Contains glycoproteins, glycolipids, free sterols, glucosylceramides.

Plays role in skin cohesion and impermeability. Forms hydrophobic barrier.

22
Q

Ratio of kcytes to melanocytes?

A

1: 5 in section
1: 36 in 3d

These are in sun protected skin

23
Q

Growth and inhibitory factors for melanocytes?

A

Growth is TGF alpha

Inhibitory is IL 1 IL 6. TGF beta

24
Q

What enzyme catalyzes melanosome production?

A

Tyrosinase. Is a copper containing enzyme

Tyrosine–>dopa–>dopaquinone

25
Q

What are the two forms of melanin?

A

Eumelanin and pheomelanin

Melanocortin I is most important in regulation of melanin production

Redheads have mutated MCRI

26
Q

BM thickness?

A

O.5-1mm

27
Q

Signaling pathway for development of dermis?

A

WNT/beta catenin

28
Q

What are the main components of the dermis?

A

Ground substance ( mucopolysaccharides) , sub papillary vascular plexus, deeper vascular plexus, fibroblasts, macrophages, mast cells, afferent nerves (meissner and Pacini)

29
Q

Describe collagen

A

3 alpha polypeptide chains. Glycine, hydroxyproline, proline, hydroxylysine make it up. Folded in triple helix.

Collagen hydroxylation- prolyl and lysyl hydroxylase. These require vit C

Cross linking of collagen molecules is done by lysyl oxidase.

30
Q

Stimulators of collagen?

A

Ascorbic acid, TGF beta, retinoic acid

31
Q

Inhibitors of collagen production.?

A

IL 1. Glucocorticoid. Interferon gamma. TNFalpha. Minoxidil Dpenicillamine

32
Q

What unique amino acids make up elastin?

A

Desmosine. Isodesmosine.

33
Q

Elastic fibers are made of?

A

Microfibrils and elastin

34
Q

Describe microfibrils

A

Made of oxytalin that runs perpendicular. Insert into BM from papillary dermis. Are finer

Élaunin fibers run parallel in reticular dermis. Are courser.

35
Q

What is the dermis extrafibrillar matrix (ground substance) made of?

A

Glycosaminoglycans (Sugars; negatively charged; bind Ions and water; ex: hyaluronic acid)

Proteoglycans (proteins with attached GAGs. Ex- versican ( forms complex with hyaluronic acid) and Perlecan (BM)

36
Q

Describe macrophages in the Dermis.

A

Phagocytic. Microbiocidal. Secretory. Wound healing. Antigen presenting

Express S100, factor 13a, CD 68, 163, 25

37
Q

Describe dermal dendritic cells

A

APC. Phagocytic. 2 types- factor 13a (dermatofibroma). CD34

38
Q

Describe dermal mast cells

A

Fried egg. histamine. Tissue edema. Ckit gain or loss of function

39
Q

In the dermis what are glomus cells?

A

Vascular smooth muscle cells on the palms and soles and digits. Allows for rapid shunting of blood from the arterioles to venules by bypassing capillaries.

40
Q

Eccrine sweat glands are intervated by what?

A

Cholinergic

41
Q

What do the post ganglionic adrenergic fibers innervate?

A

Arrector pili. Apocrine secretion

42
Q

What two molecules are found in the subcutaneous fat?

A

Aromatase. Leptin.

43
Q

At what gestation do the adnexal structures form?

A

18-24 weeks

Hair sebaceous eccrine apocrine
Have sushi every afternoon

44
Q

What are the three sections of the eccrine unit

Describe details of gland!

A

Intraepidermal spiral duct-acrosyringium. Straight dermal portion. Coiled secretory portion-in the fat

Found almost everywhere

Excrete heavy metals , thermoregulation, source of re epithelialization

Cholinergic innervation

Merocrine secretion (exocytosis from vesicles Gland is not damaged)

45
Q

Describe apocrine gland

A

Coiled secretory gland at dermis and subq fat
Excretory straight portion.

Decapitation secretion

Sweat is odorless until it reaches the surface

Basic Science (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions