biological and pathophysiology of ageing Flashcards
(26 cards)
define aging
process of becoming older / pattern of life changes as one grows older
what is gerontology
study of the ageing process
what is geriatrics
branch of clinical medicine specialised in problems of the elderly
what are the 3 theories of ageing
biological
psychosocial
developmental
what are the 6 biological theories
genetic theories
cellular theories
metabolic theories
molecular theroies
programmed theory
the run out of program theory
explain the telomere theory (genetic) + what is a telomere
telomere is the tail of chromosomes that protect the end of chromosomes from being degraded and fused with other chromosome ends
- the theory is that every time a cell replicates, it loses parts of its telomere
- the older the cell, the more time it has divided, the shorter the telomere length
- as length of telomere decreases, changes may occur in the pattern of gene expression which can affect cellular function
- when the lost DNA enriches on functional area of chromosome, cell cycle arrest can ensue
what does the telomerase enzyme do
lengthens the telomeres back up
what is the free radical theory (cellular)
- unpaired electrons are highly unstable and can react with DNA, proteins and cell membrane
- they can oxidise other compounds
- an imbalance between free radical production and clearance can result in oxidative stress
(ageing is caused by highly reactive chemicals produced randomly during metabolism)
what is autophagy
process by which defective intracellular materials are removed from the cell
what are the 3 main types of autophagy
microautophagy
macroautophagy
chaperone mediated autophagyho
how is autophagy theorised to link with ageing
defective autopahgy is thought to underlie ageing and a number of age-related diseases
what is the caloric restriction theory (metabolic)
all organisms have a finite amount of metabolic lifetime.
organisms with higher metabolic rate have a shorter life span
what is diverticular disease
condition where small pouches (diverticula) form in the lining of the bowel and push out through the bowel wall
(often found in elderly)
what are involutional brain changes
condition where folded brain tissue shrinks making the spaces between the folds deeper and wider
- enlarged ventricles/ brain issue lost
- thinning of cortex
(ppl with dementia have greatly shrunken folds)
what is osteoporosis
decreased bony tissue per unit volume bones that weakens bones making them fragile and likely to break
what 2 hormones can affect bone density
- lower oestrogen levels after menopause can contribute to a reduction in bone mineral density
- testosterone can increase bone mineral density
what are degenerative joints
joint space thinning/ cartilage lost to both ends of bone close together
and
subchondral sclerosis (pathological thickening of bone below cartilage
what is intervertebral disc disease
human intervertebral discs undergo age-related degenerative changes leading to neck pain, back pain, spine stiffness and disability
(can be bulging or thinning disc)
what is kyphosis
forward curvature of spine caused by weakness in spinal bones that cause them to compress or crack
- caused by fractured vertebrae, disk degeneration and osteoporosis
what is cause of thin endometrium
endometrium in postmenopause is much thinner
- endometrial thickness in postmenopausal women can be used in the assessment of endometrial cancer
what does BPH stand for and what is it
benign prostatic hyperplasia
- non cancerous enlargement of prostate gland
- volume of prostate typically increases with age
- prostatic hyperplasia is typically benign but a proportion will develop cancer
what is atherosclerosis
thickening of arteries caused by build-up of plague (fat, cholesterol etc) in the inner lining of artery
- calcium mineral deposits that accompany atherosclerosis serve as a marker for the diseasevto predict risk of myocardial infarction and death
what is aortic aneurysm
balloon like bulge in aorta
- aorta is prone to dilatation as one ages
- typical route of aorta can change with age to take more convoluted (twisted) path
- fear of dilated aorta is risk of rupturew
what is aspiration
misdirection of gastric contents into the lower respiratory tract
- incidence of this is greater in elders and can lead to aspiration pneumonia
