ppt they sent Flashcards
hypodermis is mainly
adipose tissue
of rows of stratum granulosum
3-5
of rows of stratum basale
1
type of cells in stratum basale
cuboidal, dividing by mitosis
components of stratum corneum
Loricrin Involucrin Profilaggrin Trichohyalin SPR's S100A proteins
protein components of granular layer
Keratin 1, 2, 9, 10
TG3
desmoglein-1
desmocollin-1
Components of spinous layer
TG1, TG5
desmoglein-2, 3, 4
Components of basal layer
Keratin 5, 14
TG2
BPAG1
Components of basal lamina
BPAG2
collagen-17
a6b4 integrin
laminin-5
trichohyalin gives
mechanical strength (cross links with itself and other structural proteins)
SP100 protein function
regulatory protein phosphorylation transcription factors Ca homeostasis cytoskeleton constituents enzyme actiivty growth and differentiation inflammatory response
function of desmoglein
component of desmosomes
BPAG stands for
bullous pemphigoid antigen
a6b4 integrin is associated with
tumor cell survival regulation
integrins are cell surface receptors for cell-cell and cell-matrix interactions
laminin 5
epithelial adhesion ligand
function of stratum granulosum
barrier to penetration by foreign materials
limits water loss
Cells in stratum granulosum contain
basophilic keratohyalin granules
membrane-coated lamellar granules
function of stratum spinosum
resistance to abrasion
Description of cells in stratum spinosum
cytoplasm filled with bundles of keratin filaments
desmosomes (intercellular bridges)
function of stratum basale
source of keratinocytes
stem cells, melanocytes
senses messages from dermis
Type of collagen in lamina lucida
collagen 17
Type of collagen in lamina densa
collagen 4
anchoring fibrils are which type of collagen
7
Dermis consists of
collagen 1 and 3
Types of connections between cells in epidermis
Tight junction
Adherens junction
Desmosomes
Gap junction
effect of UV irradiation on melanin
accelarates synthesis in melanocytes
melanin granules accumulate in
supra-nuclear region
Langerhans cells are
first immunitary sensor to external aggression
UV/bacteria/virus
to carry out function, Langerhans cells
- transform into dendritic cells
- activate T-lymphocytes
immunity response once langerhans cells activate t lymphocytes is associated with
inflammation
blood cell infiltration
Papillary layer of dermis consists of
- areolar connective tissue
- dermal papillae
- tactile corpuscles (meissner)
- dermal friction ridges
Reticular layer of dermis consists of
dense irregular connective tissue
Main proteins secreted by dermal cells
Collagen (I, III, V, VII)
Elastin
Non-collagenous glycoproteins
Glycosaminoglycans/proteoglycans
function of collagen in dermis
tensile properties
function of elastin in dermis
elasticity, resilience
function of non collagenous glycoproteins in dermis
cell adhesion and motility
function of glycosaminoglycans/proteoglycans in dermis
hydration
function of fibroblasts
secrete connective tissue in dermis
function of dendritic cells, macrophages, mast cells, and neutrophils in dermis
control immunity response to aggression
UVA irradiation causes
elastosis (elastin degradation/oxidation and cross-linking)
sebum is secreted _________ and released _______
into the hair follicle
onto the surface of the skin
function of sebum
waterproofing and moisturizing for hair and skin
hypersensitivity to androgens leads to (in terms of sebum)
increased sebum excretion
hyperkeratinization of pilosebaceous duct–>formation of microcomedone
initial changes seen in lower part of follicular infundibulum
effect of formation of microcomedone
prevents passage of sebum onto the skin
occludes follicular opening–>proliferation of P. acnes
function/location of pacinian corpuscle
sensing deep pressure
found in dermis
function/location of free nerve endings in skin
warmth/cold/pain
lower layers of epidermis
abundant in hair follicles
function/location of meissner’s corpuscles
detect light touch
dermal papilla
characteristics of innate aging (genetic)
fine wrinkling
atrophy of dermis
loss of subcutaneous fat
characteristics of photoaging (actinic damage)
Coarse wrinkling
Solar elastosis
differences in newborn skin vs aged skin
abundant collagen network–>loss of collagen, atrophy of dermis
intact elastic fiber network–>degenerated
abundance of hyaluronic acid, high degree of hydration–>loss of hydration
causes of cutaneous aging in dermis
decline in collagen biosynthesis (reduced synthesis of hydroxyproline, increased solubility of newly synthesized collagen)
decline in elastin mRNA levels
effects of aging on epidermis
- metabolism slows down
- differentiation process slows down
- defense mechanisms weaken
- skin barrier decreases
- hydration decreases
- immunity decreases
- antioxidants/repairing enzymes efficiency decreases
- intercellular communication/adhesion decreases
- oxidated waste accumulates (age spots)
- subcellular inflammation increases
what can raman spectroscopy measure
in vivo tests to show:
improved skin penetration
active transformation
what is raman spectroscopy
in vivo active penetration evaluation
shines monochromatic light->detect scattered light
small amt scattered light is shifted in energy from laser frequency due to interactions between incident EM waves and vibrational energy levels of molecules in sample
the active will have a specific raman signature which allows identification in the skin
information obtained from deep layers under surface, for real time tracking of drug in skin layers
what does RT-PCR stand for, and what does it do in general
Reverse Transcription-Polymerase Chain Reaction
shows whether or not a specific gene is being expressed in a given sample
how is RT-PCR relevant for cosmetics
study expression profile of genes involved in key skin biology processes–> use the array to identify skin care benefits of actives/mechanism of action
what do DNA chips do
identify genes that are turned on or off as cells react to a chemical (by detecting mRNA)
pattern of gene activity should indicate toxicity/offer clues to biochemical pathways by which harm occurs
(reduce need for animal testing)
High-content screening is used to identify
cytotoxicity of things such as delivery vehicles for actives
