STEP 1 Week 4 Flashcards

(220 cards)

1
Q

Trastuzimab toxicity

A

Binds to HER2 receptor

Can have cardiotoxicity, usually just causes a decrease in myoxyte contractility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What happens to endometrial cells when progesterone stimulation stops

A

Release of prostoglandins that cause vasoconstriction and release of metalloporteases that causes apoptosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Symptoms of neuroblastoma

A

Tumor of neural crest origin

Nonrhythmic eye movement and jerking movements of the trunk and limb are high indication

Usually have abdominal mass - adrenal gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is punctured during a direct suprapubic cysotomy

A

Anterior abdominal apeneurosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Most common site of anal fissures

A

Posterior midline distal to dentate line

Occurs there because less direct blood supply

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How to diagnose tetanus

A

Clinical diagnosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Effect of prolactin on sex hormones

A

High levels of prolactin suppress GnRH so can get lower LH and FSH - ammenorhea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Role of citrate in the urine

A

Citrate binds excess calcium and prevents the fomration of calcium stones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does hemoglobin release when it binds oxygen

A

It becomes more acidic so it releases protons - occurs in the lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Common medications associated with constipaption

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Most protective drug to give during heart failure

A

Beta blocker

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

SX of paroxysmal nocturnal hemoglobinuria

A

Fatigue and jaundice due to hemolytic anemia

Thrombosis - release of prothrombotic chemicals from lysed RBC

Pancytopenia

Hemosiderinuria after a few days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Biochemical change seen in alzheimers

A

Not enough Ach signaling in the nucleus basalis

This occurs because a deficiency in choline acetyltransferase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Organisms that can commonly cause eryhteme multiforme and MOA

A

Herpes and mycoplasma pneumonia

Circulating antigen is phagocytosed by peripheral mononuclear cells and DNA is given to keratinocytes. Cytotixic T-cells then see the foreign DNA and begin an immune cascade that causes epithelial damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Treatment for pyruvate dehydrogenase deficiency

A

Ketogenic diet

High intake of the ketogenic AA - lysine and leucine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Causes of vascular calcifications

A

Metabolic insults that cause epithelial cells to differentiate into osteoblast-like cells

Common in chronic kidney disease becuase:

  1. Electrolyte imbalance - hyperphsophatemia and hypercalcitemia (from dialysis)
  2. Chronic inflammation
  3. Atherosclerosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What ion does GABA cause to come into the cell

A

Chloride - has an equilobirum of -75 so hyperpolarizes the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Immune change with aging

A

Fewer production of naive B and T lymphocytes - those that are produced are often turned into memory cells of previously encountered infections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How does rhabdo cause renal damage

A

Release of myoglobin causes ATN - caused by release of heme pigment

If blood is positive but no RBC, suggestive of Rhabdo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Most common causes of acute bacterial prostatitis

A

Gram negative bacilli

E.coli, klebsiella, proteus, pseudomonas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Most common cause of increased maternal alpha fetal protein

A

Incorrect aging - often underestimate age when there is irregular meses

Other causes would be multiple fetuses, open neural tube defect/abdominal defect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the first step in the formation of atherosclerosis

A

Damage to epithelial cells

Allows for entrance of cholesterol and inflammation where monocytes come and become macrophages and eat cholesterol – foam cells. Smooth muscle then migrates to form hard cap

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Cascade of Gq receptor

A

GDP is converted to GTP which allows for conversion of PIP2 by phospholipase C into DAG and IP3. This triggers release of Ca2+ that activates protein kinase C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What kind of bias occurs when loss-to-follwup occurs more in a certain group
Attrition bias - a form of selection bias Makes it look like no correlation exists when there is
26
How does glycosuria cause hyperfiltration
Because SGLT2 also brings up Na, there will be less sodium delivered to the macula densa when glucose is high. This triggers renin and ultimately higher angiotension II that constricts efferent arteriole. This causes hyperfiltration
27
What is the axonal reaction
Occurs in the cell body when a part of the axon has been severed. See swelling of the body with pushing of the nucleus and nissl substance to the periphery as more protein is produced for regeneration
28
What systemic effect is often seen in autosomal dominant PKD
Cysts and vessel abnormalities - especially **berry aneurysm**
29
How is lithium excreted
In the kidneys, filtered and absorbed in the proximal tubule Diuretics cause volume depletion that lead to resorption of sodium and lithium in the proximal tubule - can cause overdose
30
Cancer that can be caused by celiac disease
T-cell lymphoma caused by chornic activation. of T cells with monoclonal expansion
31
How does pregnancy cause gall stones
Increased estrogen induces HMG-CoA to produce more cholesterol Progesterone causes reduced bile acid synthesis and gall bladder hypomotility
32
How does pregnancy impact the intestine
Progesterone causes small bowel hypomotility - less smooth muscle activated and less motilin Uterus can also impede the small intestine
33
Salicylate poisoning acid/base levels
Should see about normal pH There is a metabolic acidosis because salicylic acid uncouples oxygen phosphorylation so get lactic acidosis There is respiratory alkalosis because of stimulation of the medullary respiratory center
34
What is seen in peripartum cardiomyopathy
The heart expands with eccentric hypertrophy due to an increase volume, which allows for an increase in compliance. However, over time there is left ventricular failure with reduced ejection fraction
35
What is occuring during the first few weeks of TB infection
Bacteria are able to grow unchecked inside macrophages due to cord factor
36
How does CF predespose for bacterial infections
Thick, viscous secretions allow for a good environment for colonization of gram negative rods like pseudomonas - formation of macrocolonies
37
What is achondroplasia
Autosomal **dominant** mutation in fibroblast growth factor receptor 3 (FGFR3) that causes dwarfism
38
How do opioids cause hypotension
Release of histamines
39
What is subclavian steal
Occurs when there is is stenosis of the subclavian artery proximal to the entrance of the vertebral artery. The vertebral artery on the ipsalateral side will reverse flow to supply blood to the arm
40
How to diagnose giant cell arteritis
Apparently you can use an elevated sed rate and c-protein Then if those. are positive would do anartery. biopsy
41
Why does trisomy 21 predispose for early alzheimers
The amyloid precursor. protein gene is on chromosome 21 - get accumulation of beta amyloid plaques
42
What is myotinic dystrophy
Autosomal dominant CTG nucleotide repeat in DMPK gene - abnormal myotonin protein kinase Myotonia (difficulty relaxing muscles), cataracts, baldness, gonadal atrophy
43
Effect of TMP/SMX on electrolytes
Can cause hyperkalemia Impairs sodium/potassium exchange in the distal tubule, can have worse side effects if diuretics, ACEi, ARB, elderly
44
Diagnosis of. narcolepsy
Low levels of hypocretin-1 in CSF or lack of sleep latency (rapid entrance into REM)
45
How to diagnose anklyosing sponylitis
X-ray of pelvis (see inflammatory arthritis) and spine (fusion of syndesmophytes - bamboo spine)
46
Side effects of low-potency vs high-potency antipsychotics
47
MOA of n-acetylcysteine in acetopminophen toxicity
Serves as a source of glutathione which can metabolize NAPQI
48
Risk factors for esophageal adenocarcinoma
Barret's esophagus, obesity (increased gasric pressure), smoking, smoked meats
49
What is seen on liver biopsy in biliary atresia
Inflammation and proliferation of small bile ducts - caused by fibrous destruction of the extrahepatic tree
50
Greatest risk factor for pancreatic cancer
Smoking
51
Most common sites for cholesterol emboli
Vessels in the kidney, skin, GI, and CNS
52
What is lambert-eaton
Autoantibodies to presynaptic Ca2+ channels causes a drop in Ach release - proximal muscle weakness, autonomic sx, hyporeflexia Improves with use Associated with small cell lung cancer
53
Lab changes seen after starting chemo with high cell turnover
Hyperkalemia, hyperphosphatemia, increaased uric acid, increased lactate dehydrogenase All spill out of cell
54
Changes in testosterone levels with aging
Drop in free and total testosterone Compensatory increase in in LH Increase in sex-hormone binding globulin
55
What organs contain high levels of smooth er
Helps produce steroid hormones Gonads, adrenals, liver
56
Adverse effects of SERMS
Hot flashes, venous thromboembolism Tamoxifen: Uterine hyperplsia, uterine sarcome
57
Most common tracts impacted in cobalamin deficiency
DCML, lateral corticospinal, spinocerebellar
58
Structure most likely injured in posterior hip dislocation
Sciatic nerve
59
What is DiGeorge Syndrome
Microdeletion of 22q11 Defective development of pharyngeal pouches
60
What is buspirone
Anxiolytic Serotonin (5Ht1) and Dopmaine (D2) agonsit Wont cause dependence like benzos
61
What is Charcot-Marie-Tooth disease
Group out autosomal dominant progressive hereditary nerve disorders related to defective **myelin** **proteins - PMP22** gene duplication Foot deformities (pes cavus, hammer toe), lower extremity weakness, sensory deficits
62
How do SNRIs reduce neuropathic pain
Increase norepinephrine in central synpases which allows for inhibiution of pain pathways
63
What kind of receptor does glucagon use
Gs Effects mediated through protein kinase A
64
What can reduce gynecomastia in men who take GnRH and testosterone inhibitors
Tamoxifen - SERM that will work to block a relative increase in estrogen in the breast
65
Cytokines associated with atopic dermatitis
Hyper Th2 response: IL-4 and IL-13 -- increases IgE, increase vascular permeability, impair further immunity
66
Most likely brain areas affected in thiamine defiency associated wernicke korsakov
Mammilary bodies thalamus, periaqueductal gray, locus ceruleus
67
Metabolism of sublingual nitro vs oral isosorbide dinitrate
Nitro - directly into venous circulation, quick onset Isosorbide dinitrate - GI absorbption, high first pass metabolism (higher dose)
68
What is the benefit of a polyclonal immune response
Different Ig from different plasma cells can bind to different epitopse on the same antigen, so multiple Igs can be against a single antigen
69
Affinity vs avidity
Affinity - How strong the bond of a single binding site is with the antigen Avidity - How strong the entire Ig binds (so usually higher for IgM)
70
How is accuracy measured
Area under the curve Basically number of true positives and true negatives / all measured
71
What accumulates in pseudogout
Calcium PYROPHOSPHATE
72
Features of drug induced liver injury
Basically looks like viral hepatitis - fever, jaundice, anorexia, nausea, RUQ pain, rash, myalgia Liver will be atrophied and shrunken with centrilobular necrosis and inflammation of the portal tracts and parenchyma High ALT/AST, prolonged PTT (low factor VII)
73
Where are NADH, FADH2, and GTP produced?
74
What is icthyosis vulgaris
Dry and cracking skin due to fillagrin mutation that causes defective keratinocyte desquamation Also see many palmar creases
75
Why is SIADH euvolemic
When an increase in BV is seen, the RAAS system is suppressed and natreuretic peptide is produced that leads to higher GFR with loss of sodium - see more hyponatremia
76
Path of CSF
Lateral ventricles, interventricular foramen of monro, third ventricle, cerebral aquedcut, fourth ventricle, formane of luschka and megende, subarachnoid space
77
Drugs with a lower dose that are given more frequently have:
Lower average drug and peak levels and lower level of side effects
78
Where does the quadriceps femoris attach
To the tibial tubercle Osler-Schattler syndrome occurs in young athletes when there as an avulsion at the tibial tubercle because bone grows too fast and tendons cant keep up
79
Milrinone MOA
PDE3 inhibitor Increases inotropy and vasodilates
80
What is food induced allergic proctolitis
Usually seen in neonates, painless bloody/mucus stools thaat are caused by non-IgE mediated allergy to certain food - just avoid that food Inflammation of the distal colon with eosinophils
81
How can giant cell arteritis cause blindness
**Ischemic optic neuropathy**, central retinal occlusion, cerebral infarct
82
Mannitol MOA
Rapidly increases tubular or plasma osmolality which causes fluid to shift out of cells - can be good as a diuretic or in cerebral edema (from tissues to plasma) Can be dangerous in CHF or pulmonary edema
83
What do muscle biopsies look like in duchenes muscular distrophy
Muscles are replaced by fat and fibrour tissue - firbofatty muscle replacement
84
SX of short bowel syndrome
Occurs after bowel resection or in crohns Diarrhea after meals, weight loss, B12 deficiency (loss of distal illeum)
85
What is posttransplant lymphoproliferative disorder
Immunosuppression leads to less cytotoxic T cell surveillance so EBV can trigger unchecked proliferation of B cells WIll get B cell symptoms - night weats, lymphadenopathy, weight loss and will see monoclonal B cell proliferation
86
What would pyruvate kinase deficiency look like
Pyruvate kinase converts phosphoenolpyruvate into pyruvate and yields one molecule of ATP RBC dont have mitochondria so rely on this reaction to make pyruvate which eventually becomes lactate, their major source of energy. Without pyruvate kinase, ATP cant be produced so RBC lose ability to maintain membrane and transport cations - leads to **hemolysis** Would see splenomegaly due to red pulp hypoplasia - removing damaged RBC
87
Changes in renal blood vessels due to malignant hypertension
1. Fibrinoid necrosis - amorphous pink material due to cell death and fibrin deposition. Smudged necrotic endothelial cells 2. Hyperplastic arteriolosclerosis - activated platelets and injured cells release growth factors that lead to layers of smooth muscle cell and collagen with a narrows lumen - onion skinning
88
What is an acute dystonic reaction
Occurs after giving a antipsychotic - acute, involuntary contraction of a major muscle group Occurs due to dopamine antagonism in the nigrostriatial pathway
89
Function of hormone sensitive lipase
Converts triglycerides in adipose tissue into glycerol and free fatty acids
90
Sx and findings of cerebral palsy
Motor delay, hypotonia, hyperreflexia, early hand preference Will see periventricular focal necrosis becuase of sparse blood flow (if premature)
91
What nerve can be injured in an orbital floor fracture
Infraorbital nerve, continuation of maxillary nerve Parasthesia of upper lip, upper cheek, upper gingiva
92
How can CF cause diabetes
Thick accumulations in the pancreas can damage endocrine functions (islet cells) so B cell function occurs with less insulin production
93
What happens to pulm vascular resistance, CO, and plasma volume at high altitude (hypoxia)
PVR - increase (vasoconstriction) CO - increase due to sympathetic activity Plasma - dicrease. Hypoxia inhibits aldosterone causing diuresis Eryhtropoeitin is produced to raise hematocrit
94
What HIV med causes a reaction if HLA-B57 positive
Abacavir
95
Which binds both Xa and thrombin - heparin or LMWH
Heparin - it has a longer pentasaccharide sequence so can bind antithrombin and then either Xa or thrombin
96
How does sodiummbicarb treat salicylate poisoning
1. Bicarb binds free H+ which fascilitates conversion of salicylate to the charged lipophilic form which traps it in the bloodstream 2. Alkalinizes the urine which has the same effect and traps salicylates in the urine
97
SX of ALS
Anterior horns affected - LMN signs Lateral corticospinal tracts affected - UMN signs
98
What are the indirect and direct pathway
99
Effect of desmopressin on clotting
Increase circulating vactor VIII and endothelial secretion of vWF to stop bleading
100
SX of secondhand smoke in children
Recurrent infections - pneumonia, otitis media due to impaired mucociliary and macrophage function Asthma
101
Fx of fibrillin
Major component of microfibrils - forms a sheath around elastic fibers - in blood vessels, lens, periosteum Acts as a scaffold for connective tissue cells
102
What fetal cells does zika target
Neural progenitor cells
103
What conditions cause xanthelasmas
Xanthelasmas are deposits of lipid laden macrophages in the skin caused by chronic collestatic procceses like obstructive billiary lesions or PBC
104
Where is the most common site of aortic rupture during traumatic injury
The aortic isthmus - it is thethered by the ligamentum arteriosum
105
Why are diabetics at risk of hypoglycemia with exercise
In non-diabetic people, exercise leads to uptake of glucose by muscles and a subsequent reduction in insulin and release of glucagon. This leads to gluconeogenesis and glycogenolysis In diabetics, there is no insulin regulation
106
Greatest risk factors for Abdominal aortic aneurysm
Age \> 65 Smoker Male
107
Positive vs negative selection in thymus
Positive - comes first. Only T cells that are able to bind to self MHC molecules are allowed to survive Negative - second. T cells that bind with high affinity to MHC I or II undergo apoptosis
108
How can fibrates cause gall stones
They inhibit cholesterol 7 alpha hydroxylase which is the enzyme that catalyzes the formation of bile acids - cholsterol accumulates in the bile undesolved
109
What CN exits the brain at the. cerebellar peduncle
CN V
110
Side effects of carbamazapine
It is a sodium channel blocker Bone marrow suppression Hyponatremia
111
Two biggest. contribitors to angiogenesis
VEGF. ( vascular endothelial growth factor) and Fibroblast growth factor
112
Pathophys of Graft versus host disease
Donor T cells survive and travel into host and recognize host MHC as foreign - donor CD4 and CD8 cells participate in destruction
113
What enzyme and regulator regulate the first state in conversion on pyruvate for gluconeogenesis
Pyruvate carboxylase to oxaloacetate (in mitochondria) - activated by increased Acetyl-coa
114
What are the steps in de novo purine synthesis
Starts with Ribose 5-phosphate which is converted to PRPP PRPP to 5-phosphoribosylamine then to IMP
115
What causes a non-bacterial thrombotic endocarditis
Damage to valves in the presence of a hypercoagulable state - like malignancy or SLE
116
At what levels does the psoas msucle attach to the spine
T12-L5
117
How can administration of O2 lead to hypercaprnia in COPD exacerbation
Before O2, pulmonary vessels constrict in areas of low ventilation When O2 is given, these vessels dilate but there is still low ventilation so there is a perfusion-ventilation mismatch
118
Pemphigus vulgaris vs bullous pemphigoid age difference
Pemphigus is 40-60 Phemphigoid is over 60
119
What is presbyopia
The age related hardening of the lens - loss of accomodation with far vision - the image is focused behind the retina If the person had myopia before then this can be helpful
120
What are the 3 Ds of botulism
Diplopia, dysphagia, dysphonia Get a muscarinic block as well as actual muscle block - anything that uses Ach
121
What causes kidney damage in multiple myeloma
Light chain cast nephropathy - immunoglobulins are too big to be flitered but kappa and lambda light chains can
122
How can beta adronergics lead to hypokalemia
They activate the Na/K/ATP pump that increases intracellular potassium movement
123
Abx that cause long QT
Macrolides and floroquinolones
124
Cellular changes seen in pulmonary fibrosis
Damage leads to a drop in type I pneumocytes. This leads to an increase in type II that cant differentiate because of damage to cell fate pathway. There is an increase in lung fibroblasts
125
SX of phenylketonuria
Lack of pigment - hair, sking, **brain** Seizures Musty odor Intellectual disability
126
What hemoglobin chains are produced by the fetus
First few weeks produces embryonic hemoglobin (gower) with two zeta and two epsilon chains Then fetal hemoglobin is made with two alpha and two gamma
127
What growth factor triggers fibrosis and smooth muscle migration in an atheroma
Platelets adhere to abnormal epithelium and secrete **platelet derived growth factor**
128
What are the final branches of the brachial plexus
MARMU musculocutaneos axillary radial median ulnar
129
What is missclassification bias
Incorrect classification of participants based on exposure/age/etc Recall bias can be a form of missclassification bias in case-control trials because relying on interviews to estalbish classification
130
How can those with 17 alpha hydroxylase deficiency survive
In the mineralcorticoid pathway (unblocked), there is increased production of coricosterone, a weak glucorticoid
131
First line tx for status epilepticus and MOA
IV Benzos Works by enhancing the effect of GABA - binds to GABA-A receptor and stimulates more calciumr elease
132
What gene is mutated in FAP
APC - loss of function
133
4 Ts cancers found in the anterior mediastinum
Thymoma Teratoma (and other germline tumors) Terrible (lymphoma) Thyroid neoplasm
134
Drugs that increase the effects of methadone
-azole drugs ciprofloaxacin, clarithromycin cimetidine fluvoxamine
135
Why does hematuria occur in BPH
New, friable. blood vessels in the enlarged area of the prostate
136
What are the length anf time constant in nerves
Length constant is how far an impulse can go without needing another ion channel impulse, increased with more myelin Time constant is how quickly the neuron will respond to a change in membrane permeability - decerease with myelin (responds more quickly) Demyelination = decreased length contant, increased time constant
137
How do glucorticoids induce apoptosis
They can reduce expression of bcl-2
138
Location of acute vs chronic lung cancer rejection
Acute - perivascular infiltration in the small blood vessels, can spread to alveoli Chronic - submucosal inflammation of small airways (bronchiolitis obliterans)
139
What is neurosarcoidosis
Sarcoid involvement of the hypothalamus - would lead to prolactin release due to less inhibition by dopamine
140
What enzyme takes over in fructose metabolism in a fructokinase deficiency
Hexokinase - shunts fructose to glycolysis
141
How can hypovolemia cause gout flairs
Hypovolemia leads to an increase in sodium reabsorption in the proximal tubule which is tied to the absorption of uric acid - increased uric acid
142
What areas are most affected by Alzheimers
Temporoparietal lobes and hippocampus, but it is diffuse
143
Landmarks for a pudendal nerve block
Ischial spine and sacrospinal ligament
144
Location most likely to cause intraventricular hemorrahge in newborns
The germinal matrix - doesnt have as many supporting cells
145
How does nitroprusside affect heart function
Equally dilates arteries and veins so leads to a decrease in preload and afterload - same SV
146
Area of heart conduction from fastest to slowest
Purkinje, atrial muscle, ventricular muscle, AV node
147
Ramelteon MOA
Melatonin agonist Good for elderly - fewer side effects
148
Benzos MOA
Bind to GABA-A receptors and increase **frequency** of chloride chanel opening
149
What is eosinophilic esophagitus
TH2 hyperactivity that lead to eoisinophils invading the esophageal mucosa Rings, linear furrows, whitish papules
150
Phases of cells in stroke
151
Nerves associated with perianal reflex
S2-S4
152
Acute vs chronic lung injury due to radiation
Acute - exudate, hyaline membranes Chronic - TGF-B leads to dense fibrous bands with reduction in volume
153
What is lipofuscin
Accumulates with age Lysosomal breakdown products = lipid polymers, phospholipids from lipid peroxidation
154
Location and type of neuron affected in huntingtons
GABAergic neurons in the caudate nucleus
155
Most often cause of atrial flutter
Re-entrent circuit in the travocuspid isthmus - area between the tricuspid and inferior vena cava
156
Areas of the spinal column impacted in B12 deficiency
Dorsal columns - loss of proprioception Lateral corticospinal - UMN signs Axonal degeneration of peripheral nerves - parasthesias
157
Features of subacture thyroiditis
Increased T3/T4/TBG Decreased TSH Decreased uptake of. radioactive iodine - less emtabolic activity because less stimualtion by TSH Diffuse enlargment with decreased blood flow
158
Mutation in xeroderma pigmentosum
Deficiency in DNA nucleotide excision repair
159
How does NO lead to vasodilation
Catalyzes conversion of GTP to cGMP which leads to a decrease in intracellular calcium and activation of myosin light chain phosphatase. Leads to dephosphoryaltion of myosin light chain causing relaxation
160
Pathophys of Reye syndrome
Mitochondrial damage that leads to impaired fatty acid metabolism (beta-oxidation)
161
What antibodies are seen in polymyositis
Antinuclear antibodies especially **anti-tRNA synthetase** antibodies (anti-Jo1)
162
Brain area first impacted by ischemia
Pyramidal cells of the hippocampus
163
What is hidradenitis suppurative
Obstruction of folliculopilosebaceous units that leads to large ulcers and nodules in the axilla, groin, medial thighs
164
Damage to the radial nerve at what muscle is caused by repetitive pronation/suppination
Supinator muscle - see finger drop (loss of extension)
165
How does radiation induce damage
Double strand DNA breaks Creation of reactive oxygen species
166
What makes elderly people more susceptible to heat stroke
1. Tonic contraction of peripheral vasculature 2. Reduced sweat gland density 3. Loss of rete pegs and dermal capilaries - loss of effective. epidermal area for heat transfer
167
What do eosinophils look like
Bi-lobed and have orange-pink granules (major basic protein)
168
What can cause forward slippage of a vertabra
Sponylolisthesis - break of the pars interarticularis
169
Which steps of the TCA cycle require thiamine
Pyruvate dehydrogenase (to make succinyl-coA) and alpha-ketoglutarate dehydrogenase
170
What nerve lies below the piriform recess
internal branch of the superior laryngeal nerve - carries sensory innervation above the vocal cords Important for cough reflex
171
How to find GFR
Use inulin or creatinine GFR = (Urine concentration x urine flow rate)/(Plasme concentration)
172
How to find RPF
Use PAH because totally filtered RPF = (urine PAH x flow rate)/(serum PAH)
173
How to find filtration fraction
FF = GFR/RPF
174
Why can thrombocytopenia occur in pregnancy
1. Increased plasma volume with little increase in platelet level 2. Sequestration/consumption of platelets in the placenta
175
FIndings for pericarditis
Pleural chest pain Can cause a pericardial effusion that causes decreased stroke volume so get tacchycardia, low voltage ECG (blocking heart), electrical alternans (swinging heart)
176
Cause of lymphadenopathy in bacterial infection
Increased size and number of germinal centers - this is where B cells mature and select for high affinity binding In viral infections, the paracortical regions may enlarge more ( T cells)
177
How can cancer cause hypercoagulability
Adenocarcinomas produce a thromboplastin-like substance that can product intravascular coagulations that tend top migrate Seen in migratory thrombophlebitis
178
Most common cause of neonatal low T4
Thyroid dysgenesis
179
TX for diptheria
Diptheria antitoxin and abx (penicillin, erythromycin)
180
What does metastatic melanoma look like
Cells of variable pigments with abnormal nuclei (multiple)
181
Labs for herpes encephalitis
High cell count with lymphocytes and erythrocytes Normal glucose, high protein
182
Letrozole and clomiphene MOA
Letrozole - aromatase inhibitor that stops conversion of androgens to estrogens so more FSH/LH is produced Clompihene - binds to estrogen receptors in hypothalamus and pituitary and depletes them so less negative feedback and more FSH/LH
183
Which alveolar cells release elastase
Neutrophils - balanced by a-1-antitrypsin Alveolar macrophages - balanced by tissue inhibitors of metaloproeteases
184
Simulation of what nerve would help in obstructive sleep apnea
Hypoglossal - would push the tongue forward
185
What enzyme deficiency can cause diabetes
Glucokinase It is necessary to turn glucose into ATP which triggers release of insulin
186
Diagnosis of a gastrinoma
Suggestive if there are ulcers beyond the duodenal bulb If secretin is given, more gastrin will be released (secretin usually decreases gastrin release)
187
What are hamartomas
Tumors made out of the tissue of the organ where they originate but are just disorganized growth - benign
188
What are alpha and beta in biostats
Alpha - probability of type I error (so p value) Beta - probability of type II error Power = 1 - B
189
What would absence of HLA-DR cause
Absent MHC-II MHC- II is HLA-DQ, DR, DP MHC-I is HLA-A, B, C
190
Signs of vitamin A overuse
Intracranial htn (papilledema), skin changes, hepatosplenomegaly
191
How to diagnose trichamonas vaginalis
Wet mount saline microscopy - look for trophozoite
192
Interpretation of Weber and Rhinne tests
Weber - on forhead, should be the same. If conductive hearing loss, heard best in affected ear. If sensorineural, head best in unaffected ear Rhine - place on mastoid then shift to ear, should be heard longer through air. If heard better through bone, then conductive on affected ear. Sensorineural would have AC\>BC bilaterally
193
How to tell primary vs secondary polycythemia vera
Primary PV will have an increase in plasma volume with luekocytosis, thrombocytosis, and splenomegaly
194
What is seen on biopsy in rheumatic fever
Large group of multinucleated giant cells (aschoff body) and cells with linear "caterpillar" chromatin (Anitchskow cells)
195
What are glycosyltransferases (bacteria)
Enzymes that add peptidoglycan to the growing chain in the bacterial cell wall
196
MOA of mycophenolate and mofetil
They inhibit I**M**P dehydrogenase, so target the purine synthesis pathway to slow DNA replication (immunosuppression)
197
TX for someone who has a subarachnoid hemorhage
A selective calcium channel blocker to prevent vasospasm Something like nipodipine
198
Side effects of bisphosphonates
Esophagitus, osteonecrosis of the jaw, atypical bone fractures
199
What are some conditions with polygenetic inheritence
200
MOA of the "Z" medicines for insomnia
They are nonbenzodiazapenes that bind the the GABAa receptor and are agonists. Very specific and only cause hypnotic effect
201
Function of HFE and transferrin
They serve as a receptor that monitors iron loads Mutation in hemachromatosis leads to chronic actication and uptake of iron from the intestines (DMT 1) Also leads to less hepcidin release by the liver which allows for increased ferrorportin levels - higher circulating iron
202
Side effects of bile resins
GI stuff Increased release of VLDL from the liver which increases triglycerides (apparently)
203
What is the main blood supply to the femoral head
Medial circumflex artery (most likely to be damaged in a fracture)
204
Is GFR v creatine linear?
No, at the steady state, large changes of GFR wont impact creatinine But at the extreme low of GFR, creatinine is greatly impacted
205
What is abetalipoproteinemia
A defect in the MTP (microsomal transport protein) gene that causes a lack of ApoB-100 and ApoB-48 so no chylomicrons or VLDL Get no fat absoprtion - steattorhea, failure to thrive, intellectual disability, retinitis, ataxia Biopsy shows lipid laden enterocytes
206
What is cardiac index
Cardiac output per body surface area
207
What is sorbitol usually degraded into
Fructose
208
What is rheumatic factor an antobody for
For the Fc portion of IgG
209
What is the first thing to measure in metabolic alkalosis
Urine chloride Low chloride can cause a defect in secretion in bicarb
210
What is Hartnup disease
A kidney defect in the interstial transporter for neutral amino acids Includes tryptophan so can get niacin deficiency
211
What muscle is the main supinator of the arm
Biceps brachii Also flexes the elbow
212
What part of the brain processes unconcious proprioception
The anterior lobe of the cerebellum
213
Most likely spot for a diverticulum to form
Sigmoid colon
214
Area of the nephron most suscpetible to ischemia
Proximal tubule - metabolically very active
215
Most likely site for metastasis in osteosarcoma
Lungs
216
Benze exposure can cause ...
AML
217
Where are abnormal cells in myasthenia gravis cells made
Thymus - there is often a thymoma
218
What is lipid A
Part of the gram negative LPS outer membrane
219
What innervates the gastrocnemeus and soleus
Tibial - allows for plantar flexion
220