Musculoskeletal disease Flashcards
Nemaline myopathy
genetic changes in 6 genes that make up the sacromere
What happens if whole muscle cannot coordinate
will be rips in plasma membrane as muscle cells which causes muscle death and weakness
muscle
has its individual fascicles -these are made up of myocytes.Myocytes are made up of multiple bundles of myo fibrils
paramecium
each fascicle surrounded by ECM
Endomysium
each muscle cells surrounded by ECM
Muscular dystrophy
progressive muscle weakness-defect in dystrophin protein which connects dystroglycagen complex to ECM.X linked disease
what happens if the dystroglycagen complex is disrupted ?
contractions cannot be coordinated with contraction of ECM+sacromere the muscle contractions will not coordinate with contraction of ECM
Neuro muscular disease
diseases of signalling from the brain to the muscle to contract
Spinal Muscular Atrophy(SMA)
genetic or inherited diseases which affect the nerves that cause muscle contraction
Bone diseases
due to defects in base structure of the bone
What can bone diseases be caused by?
metabolic abnormalities:results in fewer minerals needed for strong bones e.g calcium, phosphorus or vitamin D
what are osteoblasts and osteocytes derived from?
mesenchymal stem cells
what are osteoclasts derived from?
haemolytic stem cells
what happens to osteoblasts and osteocytes as old age increases
fewer osteoporosis cells that give rise to osteoblasts and osteocytes -leads to less bone formation
function of osteocytes as age increases
reabsorbing bone activity goes up
osteoporosis
imbalance happens as there are less osteoblasts so less bone forming cells in bone and fewer osteocytes however more osteoclasts which are chewing up bone
Pagets disease
occurs in single or multiple bones in common sites such as spine, skull, pelvis and thigh(femur)
what does gene mutation cause?
more osteoclasts than osteoblastswhich form excess and weaker bones in the wrong place
what is the key component of ECM
collagen genes
Osteogenesis imperfecta
mutation in collagen gene which disrupts the triple helix structure which makes collagen fibre outside the cell
Bone cancer
happens due to secondary tumours that arise from defects elsewhere
Ehlers-Danios syndrome
caused by mutations in collagen 1,3 and 5 which are expressed in articular cartilage
Osteoarthritis
degenerative Arthritis which is caused due to loss of cartilage between ends of the long bones
Osteoarthritis cartilage
chondrocytes are senescent so they can’t secrete ECM to make up more of the cartilage
