3/17/17 Uworld Block 1 Flashcards
Varicella IgG ab’s suggest?
Antecedent primary VZV infection.
Ab’s gen. give immunity against chickenpox reinfection, but not herpes zoster.
Fragile X syndrome is caused by?
Increased # of CGG trinucleotide repeats on FMR1 gene (long arm of X chromosome) –> hypermethylation and inactivation of FMR1.
Activation of muscarinic receptors by Ach or cholinergic agonists leads to?
Peripheral vasodilation (synthesis of NO in endothelial cells--> smooth musc. relaxation). In other sites--> smooth musc. contraction
Damage to nucleus ambiguous of medulla?
Myoclonus
Lesions of subthalamic nucleus?
Hemiballismus– usually from lacunar infarct (HTN assoc.) in/near STN
PKU is caused by?
Inability to convert phenylalanine into tyrosine, catalyzed by phenylalanine hydroxylase
Phenylalanine hydroxylase enzyme requires?
Cofactor tetrahydrobiopterin (BH4), regenerated from dihydrobiopterin (BH2) by enzyme dihydropteridine reductase. (PKU)
Branched chain amino acids (3)?
leucine, isoleucine, valine
Deficiency= Maple Syrup Urine Dx
PKU?
Normal at birth–> severe intellectual disability and seizures if untx.
Plus hypopigmentation of skin, hair, eyes and catecholaminergic brain nuclei.
Status epilepticus acute tx?
Benzodiazepines (lorazepam IV)
Status epilepticus prophylactic tx?
Phenytoin (IV)
Isoniazid vitamin deficiency?
Vit. B6= pyridoxine–> peripheral neuropathy
Rabies encephalitis
Agitation, disorientation, pharyngospasm and photophobia–> coma and death.
*Hypersalivation
Rhabdoviridae (rabies)
SS RNA virus enveloped by bullet shaped capsule.
Studded by glycoprotein spikes that bind to nicotinic Ach receptors
Protein primary structure?
Sequence of aa linked by covalent peptide bonds.
