Block 1 Flashcards
Vomitting reflex can be activated by either _____ or _____ stimuli
Humoral or neuronal
Area postrema in the _______ has chemoreceptor trigger zone that can respond to may nerotrnsmitters, drugs, or toxins
Fourth ventricle
The _________ in the 4th ventricle has chemoreceptor trigger zone that can respond to many neurotransmitters, drugs, or toxins
Area postrema
The _____ receives information from teh area postrema, gastroinestinal tract via the vagu nerve, vestibular system ,and central nervous system.
Nucleus tractus solitarius (NTS)
The nucleus tractus solitarius is in what area of the brain
Medulla
Neurons from the nuclus tractus solitarius project to other medullary nuclei and coordinate the _______ process
Vomitng
5 major receptors involved in stimulating the vomiting reflex in the area postrema an adjacent vomiting center nuclei are _____, ______, ______, ______, _______
M1 muscarinic D2 dopaminergic H1 hitaminic 5-HT3 serotonergic Neurokinin 1 (NK1) receptors
5-HT3 receptor antagonists (odansetrno) and dopamine receptor antagonists (metoclopramid) are particularly helpful for ________ induced vomiting.
Chemotherapy-induced vomiting
When 5-ht3 receptor antagonists and dopamine receptor antagonists do not control symptoms, _____ receptor antagonists can be consdered; they prevent both aute and delayed emesis associated with chemotherapy.
Nk1 receptor antagonists (prevent substance P release)
In galactose metabolism, lactose is first broken down into ______ and _______
Galactose and glucose
Galactose is phosphorylated to galactose-1-phosphate by the enzyme_______
Galactokinase (GALK)
Excess galactose from a galactokinase (GALK) deficincy is converted to _______-
Galactitol
Excess galactose is converted to galactitol, an osmotic agent that causes _____
Cataracts
Excess glactose is converted to galactitol which spills into the urine, causing urine to test positive for a ________substance
Reducing
Which presents more seriously: a glactokinase (GALK) deficiency or a galactose -1-phosphate uridyl transferaase (GALT) defeciency
GALT
(GALK deficiencies may only present as cataracts while GALT deficiencies present in early noenates as lethargy, vomiting, and failure to thrive)
The mode of inheritence for glucose 6 phosphate- dehydrogenase (G6PD) deficiency is _____
X linked recessive
G6PD deficienct causes episodic bouts of hemolysis when red blood cells experience __________
Increased oxidative stress
How is glucose transported into the cells of most tissues
Facilitated diffusion via glucose transporter proteins (GLUT)
Transmembrane glucose transporter proteins (GLUT) are steroselectiveand have preference for ___- glucose
D
There are _____ codons for amino acids but only ____ amino acids
61
20
More than 1 ________ can code for a particular amino acid
Codon
The ______ hypothesis sates that the first 2 nucleotide positions on the mRNA codon require tradition base pairing with their complementary nucleotides on tRNA whereas the third “______“nucleotide position may undergo less stringent base pairing
Wobble
DNA polymerases are the primary enzymes responsible for DNA synthesis, which occurs ____ -> _____ direction
5’ –> 3’
Prokaryotes such as E. Coli have __ major DNA polymerases
3
High fidelity DNA replication is accomplished by the _________ proofreading exonucleas activity of all 3 DNA polyermases in prokaryotes
3’–>5’
High fidelity replication i accomplished by the 3’–>5’ “proofreading” ________ activity of all 3 DNA polymerases in prokaryotes
Exonuclease
DNA polymerase __ is unique as it is the only prokaryotic polymerase that also has 5’–>3” exonuclease activity
I
DNA polymerase I is uniqueas it is the onl prokaryotic polymerase that also has ___________ exonuclease activity
5’–>3’
5’–>3’ exonuclease activity functions by removing the ______ created by RNA primase and repair damaged DNA sequences
RNA primer
Warfarin is a ______ antagonist that inhibits epoxide reductase in the liver, thereby preventing gamma carboxylation ________ dependent clotting factors
Vitamin k
Warfarin is a vitamin k antagonist that inhibits _________ in the liver
Epoxide reductase
Vitamin K dependent clotting factors include:
II, VII, IX, X
What effect does Warfarin have on INR
Prolongs the INR
How does change in dietary intake of vitamin K induce risk of subtherapeutirc or supratherapeutic INR while on warfarin therapy?
Increase in dietary vit K intake –> increased availible vit K which counters inhibitory effect of warfarin on epoxide reductase –> subtherapeutic INR
How to antibiotics alter warfarin activity?
The gut flora produces vit K. Gram negative antibiotivs wipe out gut flora –> decreased vit K –> supratherepeutic INR (increases effect of warfarin)
Increased cytochrome P450 2C9 activity _______ warfarin activity
Decreases
Warfarin is metabolized by cytochrome P450 2C9
_______ and ______ drug class are used as antiemetics in motion sickness while ______, ______, and ________ are used as antiemetics in chemotherapy induced emesis
Antimuscarinics (anticholiergics) and Antihistamines
Dopamine receptor antagonists, setotonin receptor antagonists, and neurokinin 1 receptor antagonists
Chronic lung transplant rejection is marked by _____ ____ ______ in the walls of the small airways
Lymphocytic inflammation
_____ lung transplant rejection is marked by submucosal lymphocytic inflammation in the walls of the small aiways
Chronic
Chronic lung transplant rejection is marked by submucosal lymphocytic inflammaion int he walls of the __________
Small airways
In chronic lung transplant rejection, ingrowth of granulation tissue into the lumen leads to ______
Airway obstruction and obliteration: bronchiolitis obliterans
Chronic lung transplant rejection presents ______ after transplant
Month - years
_______ rejection usually ocurs the first day of transplantation
Hyperacute
Hyperacute rejection is caused by preformed host antibodies against _________ or ______
Donor ABO or human leujocyte antigens (HLA)
Histology of hyperacute rejection of lung transplant shows “_________”: fibrinoid necrosis with heorrhage and ischemia
White graft reaction
_______ rejection to lung transplant usually occurs within 6 months of transplat
Acute
Acute rejection of lung transplant is typically caused by _____________ to donor human leukcyte antigens
Cell mediated immune response
Histology of acute rejection of lung transplant generally shows ______________ in small blood vessels of the lung which can expand to include alveolar walls
Perivascular mononuclear infiltrates
The most important opsonins (coating proteins) are ________ and ______
Immunoglobulin G and complement C3b
On a table displaying test results and disease status, which axes is disease always on?
X axis
Equation for positive predictive value
PPV = TP/(TP + FP)
Equation for negative predictive value
TN/ (TN + FN)
What study design compares two groups (treatment and a control) in the future for outcome of interest
Clinical trial
What study design compares 2 groups (one with risk factor and one without the risk factor) in the future for disease incidence
Prospective cohort
What study desing reviews past records and compares 2 groups (one has risk factor and other does not) on disease incidence
Retrospective cohort
What study design compares 2 groups (diseased cases and nondiseased controls) in the past to compare risk factor frequency
Case-control
Which study design looks at 2 groups (one with risk factor and other without risk factor) in the present to compare disease prevelance
Cross- sectional
Endurance training can cause a systolic murmur due to ______
Eccentric left ventricular hypertrophy
Strength training can cause what changes to the left ventricle
Concentric left ventricular hypertrophy
Coronary dominance is determined by the coronary artery that:
Supplies blood to the posterior descending artery
The PDA originates in most people (right dominant) from the ______ . In left dominant people, the PDA originates from the _______
Right coronary artery
Left circumflex artery
Involvement of the ________ artery during M.I. Can cause varying degrees of AV block
AV nodal artery (most commonly a branch of the right coronaryartery although can also arise from left circumflex in left dominant)
What is an atheroma
An atherosclerotic plaque
What is released from platelets, activated macrophages, and enothelial cells to trigger smooth muscle cell recruitment from the media and proliferation of the intima?
Growth factors (platelet derived growth factor (PDGF)
Platelet derived growth factor has what effect in the vessels during formation of atherosclerotic plaque
Trggers smooth muscle cell recruitment and proliferation in the intima
A holosstolic murmur at the apex with radiation to the axilla is consistent with _____
Mitral regurge
A _______ murmur at the apex with radiation to the _____- is consistent with mitral regugitation
Holosystolic
Axilla
What extra heart sound is sometimes heard in mitral regurge
S3
Why is an S3 sometimes heard in mitra regurgitation
Blood flowing back into left atria increases left atrial pressure –> more blood reentering let ventricle during systole
Amphotericin B binds ______ to exert antiungal effects
Ergosterol
How does amphotericin B cause toxicity in human tissues
It also binds cholesterol to some degree (suppose to bind ergosterol)
List 3 important adverse effects of amphotericin B
Nephrotoxicity
Hypokalemia
Hypomagnesemia
Diptheriae has diptheria toxin which inhibits host cell protein synthesis how?
Diptheria toxin inactivates EF-2 via ribosylation
What toxin in Pseudomonas aeruginosa inhibits host cell protein synthesis and how
Exotoxin A inactivates EF-2 via ribosylation (same as diptheriae toxin)
Staph aureus’ enterotoxin, a superantigen, is responsible for what symptom of staph
It acts locall on GI tract to cause vomiting
Staph aureus’ TSS toxin, a superantigen, leads to what symptoms
TSS toxin stimulates T cells –> wide spread cytokine release and shock
C. Dif’s cytoxin B leads to what changes in the intestine
Actin depolymerization –> cell death
Necrosis of colonic surfaces
Pseudomembrane formation
B pertusis’ pertussis toxin disinhibits adenylate cyclase via ____ , increasing cAMP
Gi ADP ribosylation
What is the effect of pertussis toxin increasing cAMP production in host cell?
Increased histamine sensitivity and phagocyte dysfunction
V. Cholerae’s cholera toxin activates adenylate cyclase via ______, increasing cAMP production in host cells
Gs ADP ribosylation
What is the result of cholera toxin increasing cAMP production in host cells
Secretory diarrhea, dehydration, and electrolyte imbalances
What is the most common cause of malaria in non african countries
Plasmodium vivax
How is the latent liver phase of plasmodium vivax treated
Primaquine
Verrucous, skin colored genital lesion = _________ (anogenital warts)
Condylomata acuminatum
What virus causes condylomata acuminatum
HPV (specifically types6 and 11)
HPV infects ___________ cells through small breaks in the skin or mucosal surfaces
Basal epithelial cells (specifically stratified squamous epithelium (found in anal canal ,vagina, and cervix)
Infants can aquire respiratory papillomatosis via passage through the birth canal of mothers infected with HPV leading to warty growths on _______ which can lead to weak cry, hoarsness, and stridor
True vocal cords (only part of respiratory tract with stratisfied squamous epithelium)
Positive hepatitis B surface antibody,
Negative hep B surface antigen,
Negative hep B core antibody reflects what in the patient regarding post or present Hep B infection/vaccination?
Immunization against hep B with no prior hep B infection
CMV is defferentiate from mononucelosis by what negative test result?
CMV is heterophile antibody (Monospot) negative
How might CMV present in immunocompromised patients with reactivated infection?
Severe retinitis , pneumonia, esophagitis, colitis, hepatitis
What is the most common indicator of obesity related restrictive lung disease? (On pulmonary function test)
Reduction in ERV (expiratory reserve volume: maximum volume of air that can be expired after a normal tidal expiration)
What is the ERV on a pulmonary function test
Expiratory reserve volume: max volume of ir that can be expired after a normal tidal expiration
How does perfusion change as you approach the apex of the lung compared to ventilation?
They both decrease but the ventilation only decreases slightly while the perfusion decreases more dramatically –> increased V/Q
What is the diagnosis of a patient with a heavy smoking history, exertional dyspnea, and dilated airspaces on CT scan?
Centriacinar emphysema
Smoking induced emphysema involves oxidative injury to respiratory bronchioles and activation of ____________
Resident alveolar macrophages
Cigarette smoke ctivates resident alveolar macrophages causing inflammatory recruitment of nutrophils. Nutrophils and activated macrophages release ______ that degrade extracellular matrix
Proteases such as elastave but also cathepsins, and metalloproteinases
Where does the protease-antiprotease imbalance lead to irreversible airspace dilation in emphysema?
Distal to the terminal bronchioles
Panacinar emphysema is due to what deficiency?
Alpha-1 antitrypsin deficiency
Centriacinar emphysema is due to what?
Cigarette smoke
INR equation
INR = (PT test/PT normal) ^ ISI (international sensitivity index)
Prothrombin time tests which coagulation pathways
Extrinsic pathwa
What factors are in the extrinsic coagulation pathway and tested in PT?
VII, II, V, X, and fibrinogen
Vitamin K gamma carboxylation is required for ativation of what coagulation factors
II, VII, IX, X
Does aspiring effect INR?
No, it causes prolonged bleeding time but does not increase INR
Name the phospholipid in surfactant
Dipalmitoyl phosphatidylcholine
Inferior epigastric artery is a branch of what artery?
External iliac artery
What stain is used for malaria
Giemsa stain
How is the measles rash described
Maculopapular
Starts on face and descends
Spares palms and feet
What virus has a vesicular rash
Herpes/chicken pox
Why is a HBV infection required for hepatitis D infection
HBV provides the surgace antigen for HDV envelope
Why are patients not instructed to take nitrates at night?
Decreases tolerance
How to calculate odds ratio>
Set up a 4 x 4 with the disease on x axis
AxD)/BxC
