L50 - Skin function Flashcards
what are the different cells of the dermis?
- fibroblast and keratinocytes
- macrophages - immune system
- adipocytes - fat cells
- mast cells - inflammatory
- myofibroblasts - contractile cells
- myoepithelial cells - in sweat glands
what are the different cells in epidermis?
- keratinocytes
- melanocytes - produce melanin
- langerhans cells - denditric cells
- merkel cells - light touch and sensation
What is the skin microbiome like?
- acts like a defence
- disruption = skkin conditions
What is skin like as a barrier?
- microbial barrier
- physical barrier
- chemical barrier
- immunological barrier
- neuro-sensory barrier
What is breakdown of the skin barrier like?
- constant battle with external fungi, bacteria and viruses, immune system
- // acne, alopecia, psoriasis dermatitis
what is an example of a condition caused by the breakdown of the skin barrier?
- atopic dermatitis
- chronic, recurrent and inflammatory disease
- affect children and adults
What is healthy SC like?
- corneocytes held by corneodesmosomes
- space filled with lipid rich matrix
- prevents transepidermal water loss
What is AD like?
- disruption to skin structure
- genetic predisposition
How does the skin repair wounds?
- haemostasis - vasoconstriction of blood vessels, platelet aggregation
- inflammation - inflammatory process
- proliferation - granulation tissue
- maturation - strengthens
What is transdermal drug delivery like?
- non-invasive
- no loss due to 1st pass
- no interference from pH, enzymes, intestinal bacteria
What are ways of transdermal drug delivery systems?
- intercellular (in between)
- intracellular (through cells)
- follicular
what are the bricks and mortar in the stratum corneum?
- bricks - corneocytes
- mortar - lipid matrix
what can travel through the bricks and mortar?
- bricks - hydrophilic drugs
- mortar - hydrophobic drugs
What are the different types of transdermal drug delivery systems?
- active delivery - disruption of stratum corneum
- passive delivery - no disruption
what are the different ways of active delivery methods?
- iontophoresis - ions through membrane
- sonophoresis - ultrasound
- electroporation - creating pores by electric impulses
- photomechanical waves - photodynamic waves
- microneedle - needles pierce
- thermal ablation - localised heat creates microchannels
What is fentanyl ITS like?
- ionotophoretic TS
- management of acute, moderate-severe postoperative pain
- self-ad, pre-programmed doses
- inc patient compliance
What is botulinum toxin type A?
- treats sweaty palms, overactive sweat glands
- solid microneedle
- phase 1 clinical trials complete
What are the different passive delivery methods?
- vesicles - water filled with bilayer
- polymer nanoparticles - control release
- nanoemulsion - mixture of oil and water
What is BuTrans skin patch like?
- strong opioid, treat opioid use disorders, strong painkiller
- potent low MW analgesic on CNS
- high affinity to mu-opioid receptors, slow dissociation kinetics
- allows withdrawal symptoms to be milder/less uncomfy
What is transport through hair?
transappendageal/transfollicular
What is transport through nails?
- transungual drug delivery
- good way to treat fungal nail infections
what is regenerative medicine and skin like?
- isolation of cells, expansion
- biocompatible mats are seeded with cells
- stimulated until morphologically and functionally mimics tissue
- reintroduced to patient
What are advantages of 3D printing?
- 3D print implantable biomaterials
- precision control (no human error)
- rapid
- woundsite geometry matches
- bioprinting
what are personalised biomedical devices?
- soft implantable DDD
- treat epilepticus
- wireless monitoring, triggers subcutaneous drug release
