week 11 Flashcards
define pharmacogenetics
variations in a single gene or small group of related genes that affect the pharmacology of a drug - the study of human genetic variation as revealed by various reactions to a drug
define pharmacogenomics
variations in several genes or the genome that influence drug response the use of genetic information for the design of new pharmaceuticals
name 4 aims of GWAS
find those polymorphisms
see the genes nearby
and thus help understand the condition to- better identify new drug targets and stratify patient populations to receive appropriate treatment
define GWAS
genome wide association studies
name 3 prescriber needs for the importance of pharmacogenomics
increase awareness in order to ensure correct use of the product
safety of the patient
for their own safety - in the sense of avoiding litigation and claims of misconduct
how long does it take for keratinocytes to become cornified?
28 days
give 6 functions of the skin
- containment of bodily fluids
- protective barrier (microbial, chemical, radiation etc)
- reception of external stimuli
- body temperature regulation
- identification and or attraction
- synthesis and metabolism
what is the largest barrier to drug diffusion through the skin?
stratum corneum
which part of the stratum is 3-5 layers of flattened cells, organelles deteriorating; cytoplasm full of lamellated and keratohyalin granules?
stratum granulosum
which part of the stratum is several layers of keratinocytes unified by desmosomes (intracellular junctions that provide strong adhesion between cells). cells contain thick bundles of intermediate filaments made of pre-keratin ?
stratum spinosum
which part of the stratum is the deepest epidermal layer with one row of actively mitotic stem cells, some newly formed cells become part of the more superficial layers, occasional melanocyte and epidermal langerhan cells?
stratum basale
which part of the skin is 1-4mm thick and composed of a matrix of connective tissue, containing blood vessels, lymph vessels and nerves?
dermis
what does the cutaneous blood supply do?
regulates temperature, provides nutrients and oxygen to the skin whilst also removing toxins and waste products
what is the Cs in stratum conreum dependent on? (2)
- drug concentration dissolved in delivery vehicle
- drug partition coefficient K between skin and delivery vehicle
what determines how much drug can be dissolved in a vehicle?
the nature of the vehicle and properties of the drug molecule
name the 2 ways in which dermal penetration enhancers can mediate the effects of topical drug delivery
- direct enhancement of the skin permeability- some may cause permanent disruption to the stratum corneums barrier function
- increasing thermodynamic (solubility) and kinetic energy of the drug and resultant concentration gradient
where are corticosteroids metabolised?
the liver
how are corticosteroids excreted?
mainly by kidneys but also in bile
which phase of an emulsion are hydrophobic drugs such as corticosteroids dissolved in?
the oil phase