skin through the ages Flashcards Preview

Dermatology > skin through the ages > Flashcards

Flashcards in skin through the ages Deck (100)
Loading flashcards...
1

At gastrulation, cells divide into 3 layers: what are they?

Ectoderm

Mesoderm

Endoderm

2

ectoderm then divides into_________(2 layers)

Ectoderm

Neuroectoderm (neural crest and neural tube)

3

epidermis is derived from________

Formed from Ectoderm

4

what are the five layers of the skin?

Stratum Basale

Stratum Spinulosum

Stratum Granulosum

Stratum Lucidum

Stratum Corneum

5

at week 6, what is developed in the epidermis?

Week 6

Bilayered Epidermis

Periderm

Basal Layer

6

at week 8, what is happening in the development of the epidermis?

Week 8

Stratification begins

Intermediate layer  and Basal layer

7

defects at week 8 of skin development lead to which condition?

Defects at this point lead to Ectodermal Dysplasia

8

what defects are seen in ectodermal dysplasia?

Defects in hair, teeth, bone, skin

9

by mid-third trimester, describe development of the skin. which protein is expressed and what about the cell formation of the cell envelope? what do defects at mid 3rd trimester lead to?

By Mid 3rd Trimester: Terminally differentiated epidermal layers similar to adult skin

Filaggrin expressed and the cornified cell envelope formed

Defects at this point lead to some of the ichthyoses

10

which conditoin? mutation in what causes this?

ichythosis vulgaris 

filaggrin mutation 

11

what are the three specialized cells in the epidermis?

melanocytes (produce and distribute melanin)

langerhan cells (

merkle cells (specialized cell, neural type)

12

know: where do melanocytes originate?

neural crest 

13

where do melanocytes migrate to? 

ear(cochlear)

eye(choroid, iris, ciliary body, retnia)

skin(epdiermeis and hair follicles)

leptomeninges 

14

KNOW: Origin/migration/survival- defect leads to _________________

Origin/migration/survival- defect leads to patches of depigmentation where no migration took place (eg Waardenburg Syndrome, Piebaldism) 

15

KNOW: melanin synthesis defects lead to _____________

Melanin synthesis- defect leads to defective production of melanin (albinism) 

16

KNOW:Melanosome formation and movement- defect leads to ___________

Melanosome formation and movement- defect leads to pigment dilution
Chediak-Higashi, Hermansky Pudlak Syndrome

17

which condition? 

cause? 

disorder: Piebaldism
cause: Defective melanocyte mutation leads to patches of depigmentation

18

condition?

what causes it? 

MOSAICISM

cause: Different gene populations in one individual

Melanocytes develop along lines of Blaschko

Pigmentary mosaicism seen as linear streaks or whorls

X-linked conditions often follow lines of blaschko due to lyonization(x-incactivation) 

19

conditoin? 

what causes it 

cause: Waardenberg Syndrome
Defective survival of melanocytes leads to patches of depigmentation
Enteric ganglion cells also affected (also from neural crest)

20

condition?

what causes it? 

Albinism
cause: Due to ineffective production of melanin
Melanocytes are present, but there is no melanin
Different genes lead to different phenotypes

21

conditoin? 

cause?

condition: Hermansky Pudlak and Chediak Higashi Syndrome
cause: Ineffective transfer of melanosomes to keratinocytes lead to pigmentary dilution (silver hue).
what is affected: May affect other cells where lysosomal trafficking is important (Neutrophils, Neurons, Platelets)

22

which condtion? 

mode of inheritance? 

progression of disease? 

which three defects are present? 

which gender is it fatal in utero in? 

condition: incontientia pigmenti

XLD: x-linked dominant 

progression of disease: blaschkoid vesicles-->verrucous-->hyperpigmented-->hypopigmented lesions 

defects: ocular, dental, CNS 

FATAL in utero in males (females can survie b/c of lyonization) 

23

______ lines 

blaschko lines 

24

KNOW: dermis is dervied from _________

Derived from both ectoderm and mesoderm 

25

dermis: By 12 weeks EGA, _____________is fully functional

___________function of skin not fully developed until 3 weeks after birth

By 12 weeks EGA, dermal-epidermal junction is fully functional

Barrier function of skin not fully developed until 3 weeks after birth

26

Body surface area to weight ratio is ________ times that of adults

infants have increase ___________of topical medicines 

Premature infants have increased_________loss

Infant Body surface area to weight ratio is five times that of adults

Increased percutaneous absorption of topical medicines


Premature infants have increased transepidermal water loss (TEWL)

27

considerations in prematurity: 

1. stratum cornenum of premature babies compared to adults and full term infants? 

2. How long does it take premature babies to have competent barrier function? 

3. increased ________ loss compared to full-term infants

4. 3 ways premature infants differ from regular infants

1. thinner stratum corneum than adults and full-term infants

2. can take longer than 3 weeks for competent barrier function 

3. increased Transepidermal water loss compared to full-term infants 

4. increased risk of infections, increased percutaneous absorption of topical medicines, and decreased temp and fluid regulation 

28

what is it? 

what is its function? 

what is it composed of?(3) 

Vernix Caseosa
Protective membrane present at birth
Mechanical barrier in utero
Composed of epithelial cells, sebaceous secretions, and shed lanugo hair 

29

physiologic changes in new born: 

what is it? 

what is it accentuated with? 

how does it resolve? 

Cutis Marmorata
Accentuated with temperature decrease
Resolves with re-warming 

30

neonatal desquamation, sucking blisters, lanugo, sebaceous gland hyperplasia, and milia are all _______

physiologic changes in newborn