The Renin-angiotensin System That Helps Regulate The Constriction Of Blood Vessels And Blood Pressure.

Distribution of calcium in the body

Bone calcium (99%)

Ca^2+ and PO4^3+ form hydroxyapatite

Plasma calcium

Diffusible pool

~50% of plasma calcium is free/unbound ionic Ca2+ (physiologically important form)

~10% of plasma calcium is complexed with small molecular weight compounds (citrate, phosphate)

Non-diffusible pool

~40% of plasma calcium is bound to calcium-binding proteins and plasma proteins (albumin)

The body utilises plasma albumin-bound calcium as a circulating reserve

Cytochrome P450 Inducers & Inhibitors

The main ones can be remembered using "CRAP GPs spend all day on SICKFACES.COM".

Cytochrome P450 Inducers

These induce CYP450 activity, and thus reduce the concentration of drugs which are metabolised by this system.

Carbemazepine Rifampicin Alcohol (chronic use) Phenytoin Griseofulvin Phenobarbitone Sulphonylureas, St John's Wort, Smoking

Also topiramate.

Cytochrome P450 Inhibitors

These inhibit CYP450 enzyme activity and thus increase the concentration of drugs which are metabolised by this system.

Sodium valproate Isoniazid Cimetidine Ketoconazole Fluconazole Alcohol (acute use), Amiodarone, Allopurinol Chloramphenicol Erythromycin Sulfonamides, SSRIs Ciprofloxacin Omeprazole Metronidazole

Also grapefruit, cranberry juice, diltiazem, verapamil, clarithromycin.

Common Interactions

Medications which commonly interact with CYP450 inhibitors and inducers are:

Warfarin

Phenytoin

Combined Oral Contraceptive Pill (COCP)

Theophylline

Corticosteroids

Tricyclic antidepressants

Statins

Lamotrigine

Midazolam

I don’t know what stage of the semester you’re at right now but let someone in exam period (me) give you some advice on revision: Start early. Early as in NOW. Start now to not end up like me 

Haemosiderin staining

"Haemosiderin staining" describes orange/red/brown skin hyperpigmentation caused by haemosiderin (an iron-containing pigment found in blood) leaking into the skin.

Causes:

Chronic venous insufficiency (in lower legs)

Skin inflammation

Trauma e.g. wound, fracture, surgery

Pigmented purpuric dermatoses

Haemochromatosis

Haemosiderin staining may be exacerbated by anticoagulant use as this increases extravasation (leakage) of red blood cells into the skin.

See an example here.

Causes of drug-induced lupus

SHIP

Sulfasalazine & Sulfonamide Hydralazine Isoniazid Procainamide & Phenytoin

This is by no means a definitive list (they are many!) but these are some of the most common causes.

Cranial nerves mnemonic

On, on, on, they travelled and found Voldemort guarding very ancient horcruxes.

Olfactory, optic, oculomotor, trochlear, trigeminal, abducens, facial, vestibulocochlear, glossopharyngeal, vagus, accessory, hypoglossal.

On - Olfactory nerve (CN I)

On - Optic nerve (CN II)

On - Oculomotor nerve (CN III)

They - Trochlear nerve (CN IV)

Travelled - Trigeminal nerve (CN V)

And - Abducens nerve (CN VI)

Found - Facial nerve (CN VII)

Voldermort - Vestibulocochlear nerve (CN VIII)

Guarding - Glossopharyngeal nerve (CN IX)

Very - Vagus nerve (CN X)

Ancient - Accessory nerve (CN XI)

Horcruxes - Hypoglossal nerve (CN XII)

Causes of Acute Pancreatitis

In the UK and US, the main causes are gallstones and alcohol.

Use the mnemonic 'I GET SMASHED':

Idiopathic

Gallstones

Ethanol

Trauma

Steroids

Mumps / Malignancy

Autoimmune

Scorpion stings

Hypercalcaemia / Hypertriglyceridaemia / Hypothermia

ERCP

Drugs (including azathioprine, mesalazine, bendroflumethiazide, furosemide, steroids, sodium valproate)

Alternatively:

Some Say Money Matters But My Brother Says Big Brains Matter More

Cranial nerves functions mnemonic

Sooo… while studying the cranial nerves and their functions I came by this genius mnemonic and I just had to share it with you guys! :D

cranial nerves and their functions

Some say money matters, but my brother says big boobs make more fun. [m = motoric, s = sensorial/sensitive, b = both]

N. olfactorius (s)

N. opticus (s)

N. oculomotorius (m)

N. trochlearis (m)

N. trigeminus (b)

N. abducens (m)

N. facialis (b)

N. vestibulocochlearis (s)

N. glossopharyngeus (b)

N. vagus (b)

N. accessorius (m)

N. hypoglossus (m)

(fun)

Can - Citrate

I - Isocitrate

Keep - α-Ketoglutarate

Selling - Succinyl-CoA

Sex - Succinate

For - Fumarate

Money - Malate

Officer - Oxaloacetate

oh we are starting my favorite topic in biochemistry the tca cycle because whenever someone’s like :( it’s so hard to remember the intermediates :( i get to tell them about Can I Keep Selling Sex For Money Officer

Basic pharmacology of neuromuscular junction

ACh acts on N2 receptors (ligand-gated Na+/K+ receptors)

Block Na+ channels that propagate nerve impulse - local anaesthetics (lidocaine), tetrodotoxin

Inhibit ACh release - tetanus toxin, botulinum toxin

Competitive antagonists - vecuronium

N2 agonists - suxamethonium

Flaccid paralysis

Only cleared by plasma cholinesterase

Reversible anticholinesterases - edrophonium, neostigmine, physostigmine

Block activity of AChE

Diagnose and treat myasthenia gravis and treat glaucoma respectively

Irreversible anticholinesterases - organophosphates (pesticides, nerve gases)

Long-lived flaccid paralysis

Treat with pralidoxime within 10 minutes - cleaves OP-AChE complex