Brainscape's Knowledge GenomeTM

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


See full index

Second Year (JBR) > Dermatology Science > Flashcards

Dermatology Science Flashcards

1
Q

What is the embryological origin of the epidermis?

A

Ectoderm

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

What is the embryological origin of dermis?

A

Mesoderm

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

In week 14 of development the skin consists of?

A

Basal layer, intermediate layer, periderm (apotheoses 120 days post-fertilisation)

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

When do melanocytes, sebaceous glands, arrestor pili muscles and hair follicles develop?

A

Week 26

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

How do melanocytes form?

A

Melanoblast from neural crest migrates to uveal tract and leptomeninges
Settle in skin

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

What are the 5 layers of the epidermis?

A 
Stratum basale
Straum spinosum
Stratum granulosum
Stratum lucidum
Stratum corneum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Keratinocytes in the basal layer of epidermis attach to basement membrane via?

A

Hemidesmosomes

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

The epidermis is normally regenerated every?

A

28 days

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

How do melanocytes function in the skin?

A

Melanosomes convert tyrosine into melanin pigment with absorbs light
DCs transport melanosomes to adjacent keratinocytes and form protective melanin cap over nucleus to protect basal cell DNA

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

What colour is eumelanin?

A

Brown/black

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

What colour is phaeomelanin?

A

Red/yellow

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

What determines pigment balance in the skin?

A

MC1R gene. Protein converts eumelanin to phaeomelanin

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

1 defective copy of MC1R results in?

A

Freckling

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

2 defective copies of MC1R results in?

A

Freckling + Red hair

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

What are Merkel cells?

A

Pressure receptors

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

What is contained within basal layer?

A

Keratinocytes
Melanocytes
Merkel cells
Keratin (lots)

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

In the prickle cell layer keratinocytes are connected by?

A

Desmosomes

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

Keratinocytes in stratum spinosum produce lamellar bodies. What is their function?

A

Skin barrier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are Langerhans cells and where are they found?

A

Found in stratum spinosum, dermis and lymph nodes

Mesenchymal immune cells (APCs) - present Ag to T-cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What makes up the stratum granulosum?

A

2-3 layers of flatter unclear keratinocytes

Large keratohyaline granules with filaggrin + involucrin (proteins)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Which skin layer is the origin of the cornified envelope?

A

Stratum granulosum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What do the keratinocytes in the stratum granulosum produce? Function?

A

Lamellar (aka Odland bodies)

Lipid barrier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the stratum lucid?

A

Clear translucent layer found only in palms and soles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

The stratum corner serves as a ?

A

Tight waterproof barrier

Insoluble cornified envelope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

The stratum corner consists of?

A

Corneocytes (corneodesmosomes)
80% keratin and filaggrin
Lamellar granules (release lipids)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What makes up the epidermal basement membrane?

A

Laminin

Collagen IV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the function of the derma-epidermal junction (DEJ)?

A

Messenging - support, anchor, adhesion, growth and differentiation of basal cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

The DEJ is a _______ membrane

A

semi-permeable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What makes up the dermis?

A 
Ground substance (polysaccharide mix), immune cells
Matrix of collagen and elastin
Muscles
Blood vessels
Lymphatics
Nerves
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How is blood supplied to dermis?

A

Horizontal plexuses (supply > need)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Outline the nerve supply to skin (dermis)?

A

Somatosensory dermatomes - pacinian (pressure) and meissner (vibration) receptors
ANS - bood vessels, nerves, glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is the papillary dermis?

A

Thin dermis found just beneath epidermis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What does the reticular dermis contain?

A

Hair follicles
Nails
Skin glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What do hair follicles consist of?

A

Pilosebaceous unit

Invaginated epidermal tissue; each associated with dermal sebaceous gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What makes hair stand up?

A

Arrector pili muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

How does the arrector pili muscle attach?

A

Proximal - hair bulb

Distal - epidermis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

How are hair follicles pigmented?

A

Via above melanocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Growth of hair is under _____ influence

A

hormonal (thyroxine, androgens)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

90% of hair is in the growing phase known as?

A

Anagen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

10% of hair is involuted. Known as?

A

Catagen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

How is hair involuted?

A

Dermal papilla sinks and shrink - hair is pushed back to surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

<1% of hair (50-100/day) is in the asynchronous shedding phase known as?

A

Telogen

43
Q

What is hair in utero called?

A

Lanugo

44
Q

What is hair in childhood called?

A

Vellus

45
Q

What is adult hair called?

A

Terminal

46
Q

What makes up a nail?

A

Specialised keratins in matrix subdivisions (dorsal, intermediated, and ventral plate)

47
Q

How much does a nail grow in a day?

A

0.1 mm
Fingers > toes
Summer > winter

48
Q

Crumbling in parts of an otherwise normal nail indicates?

A

Damage to matrix subdivision preventing proper differentiation

49
Q

What are sebaceous glands?

A

Produce sebum (small oily layer) to cionrol moisture and protect from fungus/bacteria

50
Q

Where are sebaceous glands found most and what influences their secretion?

A

Most on face/chest

Sensitive to hormones - inactive before puberty

51
Q

What are apocrine glands?

A

Secrete oily fluid - odour and are part of pilosebaceous unit
Unknown function
Found mostly in axillae and perineum

52
Q

What are eccrine glands?

A

Sweat glands - control moistening and grip on soles. NaCl and HCO3 are reabsorbed

53
Q

Where are eccrine glands found?

A

Whole skin (2-4 million) - can produce >10L a day

54
Q

Under what control are sweat glands?

A

Sympathetic cholinergic nerve supply

Stimulated by mental/thermal/gustatory

55
Q

What are the three layers of skin?

A

Epidermis
Dermis
Sub-cutis (fat)

56
Q

What is hyperkeratosis?

A

Thickened surface keratin layer

57
Q

What is parakeratosis?

A

High epidermal turnover - immature keratin, nuclei persist

58
Q

What is acanthuses?

A

Increased epithelial thickness

59
Q

What is papillomatosis?

A

Irregular epithelial thickening (bumpy)

60
Q

What is spongiosis?

A

Oedema filled vesicles

61
Q

What are the functions of skin?

A 
Barrier
Metabolism and detox
Thermoregulation
Immune defence
Communication (appearance, odour) 
Sensory
62
Q

Outline vitamin D metabolism in the skin?

A

Cholecalciferol is concerted to Vitamin D3 (290-320 mm UV light)
Stored in liver with dietary vitamin D
Converted to calcitriol in kidney

63
Q

What percentage of T4 to T3 conversion occurs in the skin?

A

(0%

64
Q

how do keratinocytes in the epidermis contribute to immune defence?

A

Cell surface receptors sense pathogens and produce AMPs, cytokines and chemokine in response

65
Q

The skin contains mesenchymal T-cells including CD4+, CD8+, NK cells and other subsets. How to TH1 cells activate macrophages?

A

via IL-2 and IFN-y

66
Q

The skin contains mesenchymal T-cells including CD4+, CD8+, NK cells and other subsets. How do TH2 cells help B cells make antibodies?

A

Via IL-4, 5 and 6

67
Q

Plasmocytoid dendritic cells produce which marker of diseased skin?

A

IFN-a

68
Q

What occurs in the sensitisation phase of type IV hypersensitivity?

A

Haptens presented to CTLs and down-regulatory DC4+ T cells in lymph nodes

69
Q

What occurs in the efferent phase of type IV hypersensitivity?

A

Same happens as in sensitisation phase activate CTLs causing cytokines and chemokine to recruit leukocytes

70
Q

Group A strep causes which kinds of infections?

A

Throat, severe skin infections

71
Q

How are GAS organisms classified?

A

Lancefield (M - emm protein) antigen

72
Q

What are the major serotypes of GAS?

A

M1, M3

73
Q

Which serotypes of GAS cause severe invasive disease?

A

M3, M18

74
Q

Which GAS serotype causes epidemics?

A

emm89

75
Q

Which virulence factos do GAS possess?

A

Superantigen toxins

Haemolysins - tissue damage and ulcer

76
Q

Which adhesions and evasins do GAS possess?

A

Adhesins for oro-/naso-pharynx

Hyaluronic acid capsule to evade phagocytosis

77
Q

Which organisms causes neonatal meningitis?

A

Group B Strep

78
Q

Which classification do Enterococcus fall under?

A

y-haemolytic Strep

79
Q

E. faecalis and E. faecium are bowel ______ that may cause?

A

commensals

UTIs

80
Q

Staph aureus causes which kinds of infectioN?

A

Skin, wound, bone, joint

81
Q

Which toxins may S. aureus possess?

A

Enterotoxin
SSSST
PVL
SUperantigen TSST-1

82
Q

Most strains of CA-MRSA contain which S. aureus released toxin?

A

PVL

83
Q

How do super antigens activate more T-cells?

A

Non-Specific activation - don’t require specific antigen

84
Q

What is the standard treatment for Staph aureus unless it’s MRSA?

A

Flucloxacillin

85
Q

S. saprophytic causes?

A

UTIs in women of child-bearing age

86
Q

Which competitive bacterial flora are found in the skin?

A

S. epidermidis
Corneybacterium
Proprionobacterium (acne)

87
Q

What is a gel?

A

semisolid with HMW polymers

88
Q

What is a cream?

A

Semisolid emulsion of oil in water with emulsifier and preservative

89
Q

What is an ointment?

A

Semisolid grease without preservatives

90
Q

What is a paste?

A

Semisolid with fine powdered material

91
Q

What is lotion?

A

Solution of meds in water

92
Q

How do you calculate the rate of absorption (J) of topical drugs?

A

Kp (permeability coefficient) x Cv (concentration of drug in vehicle)

93
Q

How potent is hydrocortisone 1%?

A

Mild

94
Q

How potent is mometasone/betamethasone/valerate 0.1%?

A

Potent

95
Q

How potent is clobetasol/proprionate 0.05%

A

Very potent

96
Q

How potent are modrasone, clobetasone and butyrate 0.05%

A

Moderate

97
Q

Which anti-septic can be used as a rinse-bath for acute exudative eczema, popholyx?

A

Potassium permangenate

98
Q

How can topic drugs be systemically absorbed?

A

Transdermal - LMW

Enhanced by iontophoresis/electroporation

99
Q

What is the advantage of TDD (transdermal drug delivery)?

A

Avoids first pass metabolism

100
Q

Subcutaneous admin is just for ___ molecular weight drugs

A

high

101
Q

What are the advantages of subcutaneous administratioN?

A

Avoids first-pass metabolism

Can introduce depot

102
Q

How do different skin surfaces rank in permeability

A

nail &laquo_space;palm/sole < trunk/extremities < face/scalp < scrotum

103
Q

What is the DLQI?

A

Dermatology life quality index

Second Year (JBR) (10 decks)

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