Protein that binds to actin
- On the Z line
- (myosin binds on M line)
- Protein: Nebulin for actin
Chloride concentrated intracellularly or extracellular
- Channel opening causes influx of Cl-ions, counteracted by negative charge of the membrane
Skin changes with scurvy
- Hemorrhages and ecchymoses of skin and mucosa
- Poor wound healing
- FGF-receptor-3 deficiency
- Inhibits growth at the epiphyseal plate
Function of T-tubules
- Invaginations of sarcolemma (cell membrane)
- Phospholipid bilayer with V-gated Ca+2 channels (dihydropyidine receptors) lying next to ryanodine R located on terminal cistern of SR
- Coordinates the contraction of myofibrils
How does cytotoxic T cells induce apoptosis
- 1. Perforin forms pores and then the action of granzyme B to cleave and activate caspases
- 2. Has FasL, allowing them to kill targets by cross-linking with Fas.
Deficiency of Fas: prevents apoptosis of activated T cells allowing auto-immune cells to cause infections
Adverse affects of succinycholine
- Hyperkalemia in patients with burns, myopathies, crush injuries, and denervation
- Maligant hyperthermia (esp with halothane)
Function of colchicine
Inhibits chemotaxis of neutrophils by preventing microtubule formation
Hemolysis in sickle cell disease - lab values?
- Macrophages clearing RBC in the spleen
- Increase in unconjugated bilirubin
- Increase in LDH
- Decrease in haptoglobin as it binds free Hb and spleen removes the complex
Soleus and paraspinal muscles contain what type of fibres
- Type 1: red, rich in myoglobin
- slow twitch that derive ATP from aerobic metabolism
Myasthenia gravis causes what post-synaptic changes
- AutoAbs against the Ach-R
- Reduces the end plate AP (decreases ability of Ach to bind to post-synaptic cation channels)
Acute tx of RA? Long-term tx?
Pathogenesis of anabolic steroids
Methyl-testosterone is converted to DHT, which causes excessive follicular epidermal hyperproliferation and excessive sebum production
Action of bisphosphanates
- Pyrophosphate analogues (component of hydroxyapetite)
- Decrease bone resorption by interfering with osteoclasts
Always stand upright when taking drug to prevent reflux esophagitis
- Painful involuntary contractions of a certain part of the body with recurrent episodes
- 1. cervical torticolis
- 2. blepharospasm (initially uncontrolled blinking followed by forced closure of eyelids)
- 3. writer's cramp
Sudden, brief shock-like muscle contraction. Dx? Physiological and pathological types.
- Physiological: hiccups, hypnic jerks (when falling asleep)
- Pathological: epilepsy, CJD
Bone matrix components
- 1. Hydroxyapetite crystals
- 2. Type I collagen (link to OI)
Regulation of osteoclast differentiation
- Controlled by osteoblasts
- RANK-L and M-CSF
- Osteoclasts have receptors for these molecules
When two complete sets of chromosomes exist within an organism or cell.
- e.g. complete hydatiform mole: 69XXY
Carpal tunnel bounded by?
Contents of carpal tunnel
- Anterior: flexor retinaculum
- Posterior: carpal bones
Contents: median nerve, tendons of flexor digitorum profundus, flexor digitorum superficialis, flexor pollicis longus
Most damaged structure in the intercostal space
- (intercostal vein most protected by the costal groove as most superficial)
Mechanism of rickets
- Decreased bone mineralization
- Increased osteoblasts to deposit more osteoid to strengthen the bone, but will be soft and weak.
Compression of vertebral artery in the transverse foramina of the cervical vertebrae
- Decreased blood flow
- Motor weakness, CN problems (opthalmoplegia), cerbellar problems (ataxia)
Herniation of nucleus pulposus causes what?
- Compression of the spinal nerve
- Sx: pain, burning, tingling, muscle weakness
- Herniation occurs via rupture of the annulus fibrosis
- Involves soft tissues (nose, lungs)
- M (IgG) spike
- Mass shows plasma cells
- No BM plasma cell proliferation or skeletal lesions
- Monoclonal spike (IgG) on urine electrophoresis
- No mass, BM lesion or skeletal lesions
Breech delivery of a baby presented with hyperextended arm, paralysis of intrinsic hand muscles, and sensation loss on inner surface of hand.
- Klumpke's palse
- Upper brachial plexusi injury
Histo of utricaria (hives)
Dilated superficial lymphatic channels
Granular complement and IgG at the dermal-epidermal junction
Urine turns black upon standing at room temperature
Alkaptonuria (athritic dz where accumulated homogenisitc acid deposits in the tendons, cartilage, etc.)
Anterior dislocation of shoulder damages what nerve?
- Axillary n.
- Shoulder exits inferiorly first and axillary nerve exits inferiorly from the axilla
Abductor pollicis longus vs abductor pollicis brevis. Nerve supply?
Muscles that elevate the tongue to the roof of the mouth
- 1. Styloglossus (CN XII)
- 2. Palatoglossus (CN X)
Disorder due to deficiency in glycoproteins
Hunters and Hurlers
Chronic corticosteroid therapy leads to what muscle problem
- Atrophy of type II fibres
- Proximal muscle weakness
- Ragged red fibres in the muscle
- Proximal muscle weakness
- Eye involvement
Erythema multiforme causes
Immune complex deposition in dermal blood vessels
- a) Mycoplasma, Herpes, Chlamydia
- b) Sulfa drugs, Phenytoin, Penicillin
- c) Neoplasia, sarcoidosis
What muscles insert on the greater trochanter of the femur?
Gluteus minimus, medius, and piriformis
Muscles that insert on the lesser trochanter of the femur?
Muscles that insert on the gluteal tuberosity of the femur?
Crusted red erythematous lesions seen with multiple blisters, and full epidermis peeled off in a newborn
Staph-scalded skin syndrome
Site of latency for CMV
Site of latency for VZV
Site of latency for EBV
- dorsal root ganglia
- B cells