Genetics (population genetics, gene regulation, epigenetics)
This is an example of heterozygote advantage
Sickle-cell Anemia.
Individuals who are heterozygous for the sickle cell allele are at a selective advantage because they are protected against malaria but do not get sickle cell disease.
A 65 year old is brought to her physician for evaluation of her swollen big toe. Aspiration of her big toe showed needle shaped crystals. The patient was diagnosed with gout. She was started on medication that inhibits which step?
IMP- Inosine
GMP- Guanosine
Inosine-Hypoxanthine
Hypoxanthine-Xanthine
Adenosine-Inosine
Hypoxanthine-Xanthine (Allopurinol inhibits xanthine oxidase)
A patient is suspected to have progressive muscle weakness due to an autoimmune disease affecting the neuromuscular junction. Which of the following would be used to treat this disorder?
Edrophonium
Physostigmine
Malathion
Pyridostigmine
Atropine
Pyridostigmine
The maximal effect that a drug could evoke is defined as?
Efficacy
When an allele is introduced to a small population and grows to a high frequency (mostly in isolated geographical areas due to religion, similar culture, etc)
Founder Effect
A 10-year-old boy comes to his pediatrician for evaluation of recurrent lung infections, over the past few months. Laboratory studies showed that the patient has remarkably low immunoglobulins. The patient has decreased T and B cell functions. Which of the following enzymes are most likely deficient?
A. Xanthine Oxidase
B. Purine Nucleotide Phosphorylase
C. Adenosine Deaminase
D. 5’ nucleoside
E. Guanase
C. Adenosine Deaminase (Autosomal Recessive SCID)
A patient is suspected to have progressive muscle weakness due to an autoimmune disease affecting the neuromuscular junction. Which of the following would be used to diagnose this disorder?
Edrophonium
Physostigmine
Neostigmine
Pyridostigmine
Atropine
Edrophonium
These are examples (given in your lectures) of drugs that increase the synthesis of cytochrome p450 enzymes.
Rifampin, Phenobarbital, Carbamazepine.
Cytochrome p450 enzymes are responsible for the metabolism of 80% of drugs in clinical use. So, these drugs increase transcription of cytochrome p450 enzymes.
A 4 year old child is seen by the doctor and is found to have mild intellectual disability and rapid weight gain associated with a huge appetite. The pediatrician later makes the diagnosis of Prader-Willi syndrome. Molecular diagnostic analysis of this child will likely reveal which of the following?
Promoter mutation of the maternal SNRPN gene
Inability to produce SNRPN protein
Duplication of the paternal UBE3A gene
Maternal deletion of the UBE3A gene
Paternal imprinting of the SNRPN gene
Inability to produce SNRPN protein (only maternal UBE3A expressed)
This enzyme catalyzes extracellular crosslinking between collagen fibers, strengthening them. It also requires copper as a cofactor.
Lysyl Oxidase
A 25 year old is brought to the emergency department by ambulance after being found unconscious in the street. He has fever, tachycardia, dilated pupils, facial flushing, xerostomia, and dry skin. Which class of drugs is mostly responsible for his symptoms?
Acetylcholinesterase
Muscarinic antagonist
Muscarinic agonist
Adrenergic agonist
Adrenergic antagonist
Muscarinic antagonist (Atropine is used to treat organophosphate poisoning, M3 and M2 blockade)
These are examples of drugs(given in your lectures) that inhibit cytochome p450.
Cimetidine, Erythromycin, Chloramphenicol, Grapefruit juice
cytochrome p450-responsible for breakdown of drugs.
Inhibition of cytochrome p450 -> slower metabolism of drugs and thus, drug conc. in blood could reach high levels.
The lacI gene encodes this protein that shuts the system down when lactose is not present
the repressor protein
The Lac Operon in bacteria is turned on (inducible) when lactose is added to the bacteria cell.
Once lactose binds, the isomer allolactose forms which binds to the repressor and takes it off, causing transcription.
A couple present to a genetic specialist because they are concerned about having a child with sickle cell anemia. They come from a region in africa where this autosomal recessive disease displays a psuedo-dominant inheritance. They're told that it is likely that they'll have a child with this disease. The normal treatment for sickle cell includes hydroxyurea which through an unknown mechanism upregulates fetal hemoglobin. Which of the following does hydroxyurea most likely inhibit?
Conversion of xanthine to uric acid
Conversion of ribonucleotide diphosphate to deoxyribonucleotide diphosphate
Conversion of dihydrofolate to tetrahydrofolate
Conversion of inosine monophosphate to guanosine monophosphate
Conversion of hypoxanthine to insonine monophophate
Conversion of ribonucleotide diphosphate to deoxyribonucleotide diphosphate
A 21 year old man is brought to the emergency department unconscious after a night of heavy drinking. Physical examination shows absent breath sounds and an endotracheal tube is inserted. Which of the following drugs was given to ease this procedure?
Botulinum Toxin
Epinephrine
Pyridostigmine
Succinylcholine
Tubocurarine
Succinylcholine
The blood brain barrier restricts these type of molecules...
polar molecules.
Bloodbrain barrier restricts polar molecules so drugs have to be liposoluble to enter CNA or have an active transporter.
DNA sites where proteins and trans regulatory elements will bind
Cis regulatory elements
(the transcription factors and proteins bind to these DNA sites to regulate transcription)
Follow up:
Think about what Trans regulatory elements are... (it was in the question)
Vitamin C.
Causes decreased stability and strength of collagen.
One of your patients presents with chest pain. You do an EKG, and blood work that shows no evidence of a myocardial infarction. Because of her age and risk factors, you want to investigate the cardiac status further. The patient uses a walker and is unable to participate in a treadmill-based stress test. What can you giver to test the health of her heart?
Isoproterenol
Pindolol
Dobutamine
Propranolol
Clonidine
Dobutamine (B1 agonist- increases myocardial O2 consumption. Basis of dobutamine stress echocardiogram)
Main organ of drug metabolism
Liver