UWorld Flashcards
What is the pathogenesis of mast cell and basophil degranulation in an allergic reaction?
IgE is bound to the high affinity IgE receptor (FceRI) on mast cells/basophils.
IgE molecules then crosslink due to an antigen–>
aggregation of the FceRI receptors on mast cells–>
activation of tyrosine kinases not assoc w/receptor–>
intracellular signaling–>degranulation.
How is IgE present in the circulation?
It binds non-covalently (disulfide or peptide bonds instead) to the FceRI receptor on mast cells and basophils via its Fc region. Little is free in the serum.
What vasoactive substances are released from the granules of mast cells and basophils in anaphylaxis?
Histamine and Tryptase (mainly mast cells)
What is the blood supply to the proximal ureter?
The distal ureter?
Middle ureter?
Branches of the renal artery
Superior vesical artery
Anastomotic and variable. Usually: Gonadal, common/internal.
In kidney xplant: distal ureter susceptible to ischemia due to loss of anastomoses with proximal ureter, iliac, aorta and uterine arteries.
What are treatments and preventative measures for calcium oxalate kidney stones?
- Increasing fluid intake
- Citrate (binds ionized Ca++)
- Thiazides
Neurofibromas in NF1 are composed of what cell type?
Benign neoplasms of Schwann Cells (derived from neural crest)
What are the signs and symptoms of Vitamin D excess?
Hypercalcemia, hypercalciuria, stupor and loss of appetite
What are the signs and symptoms of Hypercalcemia?
Stones, bones, groans, thrones, moans
AKA Renal stones, bone pain, abdominal pain, urinary frequency, anxiety/altered mental status
What is the pathogenesis of the S/S in hypercalcemia?
High Ca++–>depolarization of neuromuscular membranes–>S/S (muscle weakness, constipation and mental status chgs)
What serum abnormality can granulomas cause?
Granulomas are maintained by activated mphages. Activated mphages can produce 1-alpha hydroxylase–>1,25 vit D (calcitriol)–>Hypercalcemia and hypercalciuria. Similar process occurs in Hodgin’s and Non-Hodgkin’s lymphoma.
Describe the onset and distribution of Thiopental
It first onsets rapidly in the brain.
Then it distributes to skeletal muscle and fat quickly. This causes loss of its activity.
What are the S/S of Type III Hypersensitivity reactions?
Vasculitis and systemic manifestations (Fever, arthralgias, skin rash)
What kind of hypersensitivity reaction can chimeric monoclonal antibodies cause?
Type III (They can cause Serum Sickness).
Serum Sickness S/S: Fever, skin rash, arthralgias
How are case control studies designed to decrease confounding bias?
Matching: putting similar pts (same age, race distribution) in experimental and control groups during selection
Where is Vitamin A primarily stored?
Liver in the stellate (Ito) cells. Stores last around 6 months.
What cell does Renal Cell Carcinoma arise from? What is its histology?
Proximal Convoluted Tubule
Appearance is polygonal or cuboidal clear cells in the clear cell variant (most common).
Most common renal neoplasm. Often yellowish grossly b/c of glycogen and lipids.
What cancer arises from collecting duct cells from the renal tubules?
Oncocytoma.
Rare, well-differentiated with lots of mitochondria
What neoplasm arises from cells of the renal pelvis?
Transitional Cell CA of the kidney.
Forms papillary tumors composed of urothelium with a thin fibrovascular stalk
What are the proteins associated with MHC Class I and II, respectively?
Beta2-microglobulin and Invariant chain
In what layer of the bowel wall are the Auerbach and Meissner plexuses located?
Muscularis and Submucosa, respectively.
Auerbach=myenteric plexus
Meissner=submucosal plexus
What is seen on histology in Kaposi’s Sarcoma?
Spindle and epithelial cell prolif, RBC extravasation and inflammation.
Caused by HHV 8 in susceptible individuals. Infx begins in vascular and lymphatic endothelial cells.
What does the QRS complex correlate to in the Myocyte Action Potential?
Phase 0, depolarization
What drugs inhibit dihydrofolate reductase–>dec reduction of folic acid to tetrahydrofolate?
Trimethoprim: for bacterial growth
Methotrexate: antimetabolite
Pyrazinamide: parasite (malaria and toxo)
MoA of Ezetimibe
Dec intestinal cholesterol absorp via inhibition of NPC1L1 (Niemann Pick C1-like1),
which xports cholesterol from gut lumen into enterocytes–>
dec cholesterol in hepatocytes–>inc liver LDL receptor expression
–>dec blood cholesterol
What is a drug related complication of advancing Parkinson Disease?
Levodopa’s therapeutic window narrows (maybe due to further nigrostriatal degen) so the length of time that the serum level=effective dose decreases–>inc motor issues.
In very advanced PD, motor instability becomes independent of meds–>complete unpredictability.
Germ tubes at 37 deg C, think?
Candida albicans. Normal flora of skin, mouth, vagina, intestine.
Where does H. Pylori colonize?
Antrum of stomach in prepyloric area.
Colonization here–>inc H+ production–>dec pH in duodenum–>ulceration.
It is the dec pH that causes the duodenal ulcers, NOT direct infection of duodenum by H. pylori.
What type of gland are sebaceous glands? What is their MoA?
Holocrine
Mech: Cell lysis releases entire contents of cytoplasm and cell membrane
What are examples of Merocrine glands?
Salivary glands
Eccrine sweat glands
Apocrine sweat glands.
MoA: cells secrete via exocytosis
Besides sebaceous glands, what is another type of holocrine gland?
Mebomian glands (in the eyelid near lashes, secrete oil to give tears staying power).
Holocrine MoA: cell lysis–>release of whole cytoplasm and cell membrane
Describe the pathogenesis of inflammatory acne
- Keratin plug forms–>blocks sebum release
- Sebaceous gland hypertrophy–>inc sebum prod
- Sebaceous gland colonized by Propionibacterium acnes
- P. acnes cleaves triglycerides in sebum–>inflammatory fatty acids
What are the main subtypes of exocrine glands and their MoA?
Apocrine (vesicle release)
holocrine (cell lysis)
merocrine (watery via exocytosis, no loss of membrane)
What is required for new nucleotides to be added to replicating DNA?
a free 3’ hydroxyl group.
AZT is a thymidine analog with an azido group, not a 3’ hydroxyl–>chain termination
How does Zidovudine (AZT) target HIV?
AZT is a NRTI, so it is an analog of nucleotide, thymidine.
But, it has an azido group, not a 3’ hydroxyl group–>halt of chain elongation when AZT is incorporated into the growing DNA chain (no 3’-5’ phosphodiester bond is formed)
What is the pathogenic basis of silicosis?
mphages intake silica–>impairment of mphage phagolysosomes–>extrusion of lysosomal enzymes and intracellular bacteria.
Lysosomal enzyme extrusion is thought to lead to alveolar and interstitial lung injury.
Also thought that mphages undergo apoptosis w/prolonged silica exposure.
The lysosomal impairment in mphages is the reason for inc mycobacterial susceptibility in silicosis
Male homolog to the labia minora is? What does a defect in this homolog lead to?
Ventral shaft of the penis
Defect leads to hypospadias (ventral is the underside of penis)
Labia minora and ventral shaft of penis are derived from the urethral folds
What embryologic structure becomes the penis/clitoris?
Genital Tubercle.
Epispadias is an opening on dorsal aspect of penis due to improper position of GT in 5th wk of gestation
Epispadias is caused by what specific error in dvlpmt?
Improper plcmt of the genital tubercule during the fifth week of gestation
High renin, high aldosterone, hypertension, hypokalemia, muscle weakness. Pt is young, shows no sign of renal or vascular risk factors for HTN. No diuretics. Dgs?
Reninoma, benign neoplastic growth of Juxtaglomerular cells
What are some S/S of schizotypical personality disorder?
Eccentric Behavior
Odd Thoughts (especially magical thinking like clairvoyance)
Perceptual distortions
Social anxiety (no close relationships, as anxiety doesn’t dec w/familiarity)
What is the first line therapy for acute delirium (agitation and psychosis symptoms especially)?
Haloperidol (High potency D2 blocker in CNS)
What is the antibody difference between diffuse and limited scleroderma (systemic sclerosis)?
Diffuse: anti-SCL-70 ab
Limited: anti-centromere ab
Limited is aka CREST syndrome and is more benign than diffuse scleroderma
What is CREST Syndrome?
A limited type of systemic sclerosis (scleroderma) with a more benign course and specific features
C: Calcinosis (deposition of calcium in skin)
R: Raynaud’s
E: Esophageal dysmotility
S: Sclerodactyly
T: Telangiectasia
Define Plummer-Vinson Syndrome
Triad of Iron Deficiency anemia, esophageal webs and dysphagia.
Can have atrophic glossitis.
Inc risk for esophageal squamous cell CA
What is locus heterogeneity?
One phenotype produced by mutations at disparate gene loci
What processes is biotin important for? (4)
Biotin (vitamin B7) is used in carboxylation rxns.
- Pyruvate Carboxylase: Pyruvate>oxaloacetate
- Acetyl-CoA carboxylase: acetyl-CoA>malonyl-CoA
- Propionyl-CoA carboxylase: propionyl-CoA>methylmalonyl-CoA
- Beta-methylcrotonyl CoA carboxylase: 3-methyl-crotonyl-CoA>3-methylglutaconyl-CoA (degradation of leucine)
What are the S/S of Biotin deficiency?
Dermatitis
alopecia
enteritis.
Caused by abx and excess ingestion of raw egg whites (avidin binds biotin)
Describe the pathogenesis of Hemolytic Uremic Syndrome (HUS)
Most often a shiga toxin from shigella or e. coli O157:H7–>dmg to endothelial cells–> platelet activation in the form of microthrombi.
Microthrombi then lodge and start cleaving RBCs forming schistocytes.
Dmg to endothelium in glomerulus happens about 1/2 of the time–>AKI
What are the lab findings in Hemolytic Uremic Syndrome (HUS)?
dec Platelet count
dec Hgb (microangiopathic hemolytic anemia)
inc bleeding time
inc lactate dehyrogenase
inc indirect bilirubin
inc BUN and Creatinine (Acute Renal Failure)
What processes of the Hep B virus–>Hepatocellular Carcinoma?
HBV infects the cell then integrates itself into the host DNA via reverse transcriptase.
This integration allows continued xscription of HBV proteins, like Hbx protein. Hbx is an oncogene and deactivates p53.
What are the two main types of SCID?
Presentation?
X-linked recessive (defect in IL-2R gamma chain)
Autosomal recessive (defect in adenosine deaminase)
Presents with FTThrive, chronic diarrhea, thrush, recurrent infx (viral, fungal, bacterial and protozoal)
What is deficient in chronic granulomatous disease? What is the hallmark test for CGD?
NADPH oxidase–>no respiratory burst.
Susceptible to catalase (+) organisms.
Nitroblue tetrazolium test (-) in CGD (no blue color).
Obsolete test, use dihydrorhodamine test now (will be abnormal–>dec green fluorescence)
What proteins can bind DNA? (6)
Transcription Factors (c-MYC, n-MYC, L-MYC, CREB, Heat shock protein, etc)
Steroids
Thyroid Proteins
Vitamin D receptors
Retinoic Acid receptors
DNA transcription proteins/replication proteins
Define Pleiotropy
Multiple, seeminly unrelated defects in various organ systems that arise from 1 genetic defect.
What is the function of Club Cells (Clara Cells)
Protect the bronchiole lining
Secrete GAGs and surfactant like substance
Stem cell for bronchiolar epithelium
Detoxification of harmful substances -via cytochrome P450 enzymes
What is the description of ring-enhancing lesions on MRI?
Mass that is a rim of contrast enhancement surrounding a dark center (central necrosis).
What is the most common method of transmission of Toxoplasma gondii?
What is the Treatment?
Cysts in meat (especially undercooked lamb or pork)
Pyrimethamine and sulfadiazine for Tx
Prevention via TMP-SMX when <100 CD4
What genetic mutations can lead to Autosomal Dominant Polycystic Kidney disease?
Mutation in PKD1 on chromosome 16 (vast majority of cases). PKD1 codes for polycystin-1 (located in renal tubule epithelial cells)
Mutation in PKD2 on chromosome 4 (~15%), coding for polycystin-2 (located in renal tubules and other tissues).
What adult nervous structures derive from neural crest cells?
Schwann Cells
Dorsal Root Ganglia (pseudounipolar neurons)
Pia and arachnoid meninges
Chromaffin cells of adrenal medulla
What adult structures, seemingly mesodermally derived, are actually derived from neural crest? (6)
Endocardial Cushion
Aorticopulmonary septum
Odontoblasts
Pharyngeal arch cartilage
Melanocytes
Parafollicular (C) cells of Thyroid
Where is Lipoprotein Lipase located?
Vascular endothelial cell membranes in the capillary beds of adipocytes
What does a decreased diffusing capacity of the lungs for CO indicate?
Decreased surface area for gas exchange or increased thickness of the interface. So emphysema or interstitial lung disease, respectively.
What is the primary cytotoxic effector molecule made by H. pylori?
Ammonium, because of its urease activity
Mutation in what gene leads to Autosomal Recessive Polycystic Kidney Disease?
PKHD1 encoding for fibrocystin, found on chromosome 6.
What is Dehydroepiandrosterone (DHEA)
An androgen precursor made from 17 ketosteroids.
What zones of the adrenal glands does ACTH affect?
What products can high levels of ACTH lead to?
Reticularis and fasciculata of the cortex
High ACTH can cause inc:
Cortisol
DHEA
androstenedione–>estrone/estradiol or
testosterone–>DHT
17 ketosteroids
11-deoxycortisol
What is the mech of PCOS?
inc LH as compared to FSH (d/t too much GnRH or dysfnx of HPO axis b/c of high insulinemia)–>inc androgens from theca cells–>dec follicle maturation.
Follicles degenerate–>cysts and anovulation
How do you treat community acquired pneumonia?
If outpt and healthy: macrolide or doxycycline
If outpt and comorbidity: fluoroquinolone or beta-lactam+macrolide
If inpt: fluoroquinolone or antipneumoccal beta-lactam+macrolide
What types of organisms is ceftazidime good against?
Gram (-) infx resistant to other Beta lactams and pseudomonas. Poor gram (+) cocci coverage.
What is an important aspect of privacy and confidentiality
Patients have a right to privacy, even from family. Ask family to wait outside or ask permission to share news with them prior to bringing up anything about pt’s care.
MoA of colchicine
Binds and stabilizes tubulin–>inhibition of microtubule polymerization–>dec leukocyte migration and phagocytosis. This inhibition of leukocytes dec inflammation reducing symptoms.
What is the mesonephros?
The metanephros?
Embryonic kidney
Definitive Kidney
What induces the formation of the metanephros?
The ureteric bud, portion of the mesonephric duct.
What kind of agent is trihexyphenidyl?
A muscarinic antagonist used for Parkinson Disease
What are the symptoms of Wallenberg Syndrome?
Where is the occlusion?
Nucleus ambiguus dysnfx specific: hoarseness and dysphagia.
Vomiting
Vertigo
Nystagmus
dec pain and temp from ipsilateral face and contralateral body
dec gag reflex
ipsilateral Horner syndrome
Limb Ataxia
PICA
Describe the genetics of familial hypercholesterolemia
Autosomal Dominant
Displays gene dosage. If patient inherits two mutated alleles instead of just one–>much more severe disease.
6x higher cholesterol and death in 20s/30s from MI/CVA.
What does negative birefringence mean in regards to gout?
Under polarized light, the gout crystals are needle-shaped, and yellow when in parallel to the light and blue when perpendicular.
What are the clinical S/S of an Atrial Septal Defect?
Pulm HTN–> Atrial Arrhythmias
Exercise Intolerance
SOB
FTThrive
What is the mechanism of the lactic acidosis and hyperuricemia seen in Hereditary Fructose Intolerance?
ATP is used up creating glucose via gluconeogenesis–>inc AMP levels. AMP is degraded to uric acid–>hyperuricemia
Uric acid and lactate use the same transporter in the kidney, so hyperuricemia–>dec lactate excretion–>inc serum lactate
Why does venous blood have higher hematocrit than arterial?
There is an increase in chloride w/in the RBCs. This draws water inside the RBC–>inc RBC volume, aka inc hematocrit
What are the features of von Hippel-Lindau disease? (3)
- Mutation of VHL gene on chromosome 3p
- hemangioblastomas (vascular tumors) of retina, cerebellum and/or medulla
- bilateral renal cell carcinoma
What is the pathogenesis of Paroxysmal Nocturnal Hemoglobinuria?
Defect in Phosphatidylinositol glycan A gene (PIG-A)–>dec GPI anchor protein. GPI needed for CD55 (decay accelerating factor) and CD59 (c3 convertase inhibitor).
RBCs, WBCs, and platelets are then lysed by complement due to lack of CD55 and CD59.
What receptors are in the uterus smooth muscle?
alpha 1(inc contraction) and beta 2 (inhibit contraction)
What is the gross endoscopy view of acute gastritis?
Erythematous mucosa with petechiae and/or ulceration.
What are causes of acute gastritis?
- Uremia
- NSAIDs
- Alcohol
- Steroids
- Smoking
- burns
- shock
- head trauma
What is the most common way that Herpes Simplex Virus is passed from mother to child?
Transvaginally during a current outbreak. So baby gets it as he/she is delivered.
Can also occur transplacentally but is less common
What is a very serious adverse effect of triptans?
Hypertensive emergency
What structure runs along the edge of the lesser omentum and what does it contain?
Hepatoduodenal ligament
The portal triad: Hepatic artery, portal vein, and common bile duct
What does a leukocyte esterase (+) and nitrite (-) urinalysis indicate?
Examples?
Gram (+) UTI. Two examples are enterococcus faecalis and staph saprophyticus.
What is the mechanism of action of gemfibrozil?
Fibrate: activates peroxisome proliferator activated receptor-alpha–>inc of Lipoprotein Lipase expression and dec hepatic VLDL production
What drugs are fibrates?
Gemfibrozil
Fenofibrate
Clofibrate
Bezafibrate
What are side effects of fibrates?
Gallstones (inc cholesterol content of bile via inc of LPL)
Myopathy
What are the histologic findings on biopsy of the testicles in Klinefelter syndrome?
Sparse, completely hyalinized seminiferous tubules. Lack of germ cells and rare Sertoli cells.
What are the predominant antibodies found in Type 1 DM?
Anti-glutamic acid decarboxylase
What does a positive capillary filtration pressure indicate?
That fluid is moving from intravascular to extravascular.
When are drug-drug interactions checked during the process of prescribing?
Just prior to dispensing the medication
Membranous nephropathy is defined by what kind of antibodies?
Phospholipase A2 receptor antibodies (PLA2R)
Besides Duchenne MD and BMD, what disease has a mutation in dystrophin?
X-linked familial dilated cardiomyopathy
Vaccines against which bacteria use a capsule conjugated to toxoids (like diphtheria and tetanus toxoid)?
S. Pneumo
N. meningitidis
H. Influenzae
What class of medications inhibits fungal cell wall synthesis by blocking 1,3-beta-D-glucan synthesis?
Echinocandin antifungals (micafungin, caspofungin)
Recurrent, hexagonal, flat kidney stones in a young person, think?
Cystinuria, an amino acid transport disorder.
What is the mechanism of acute graft rejection?
Recipient T-cells activated against donor antigen
What muscle group plays the largest role in the Valsalva manuever?
Rectus abdominis.
Valsalva is exhaling forcibly against closed glottis.
What is a side effect of direct vasodilators? (hydralazine and minoxidil)
Sodium and water retention d/t RAAS activation–>tachycardia and peripheral edema
What synapses do organophosphates act upon?
Muscarinic AND Nicotonic
This means that you get not only DUMBBELS but muscle paralysis, seizures and CNS depression too.
What type of bias is caused by loss of study participants due to dropout?
Attrition bias, a form of SELECTION bias.
Only occurs when there is a disproportionate dropout from one group over another
Where should you biopsy to definitively diagnose Celiac Disease?
Dudoenum or ileum
exposed to more gliadin
In leprosy, a (+) PPD test indicates what?
Intact Th1 response. This means it is the Tuberculoid form, better prognosis.
What characteristics are common in Tuberculoid leprosy?
Strong Th1 response with + PPD and inc of certain cytokines: IL-2, IFN-y, IL-12
Activates mphages, dec extent of disease.
What is characteristic of lepromatous leprosy?
Th2 response. No granulomas, (-) PPD.
Terrible prognosis, lots of skin damage and systemic disease with acid-fast bacilli in mphages.
Inc cytokines: IL-4 IL-5 IL-10
Where does the fibular nerve divide?
What does it divide into?
It divides at the fibular neck
Deep peroneal n (inn anterior compartment)
Superficial peroneal n (inn sensory to dorsum of foot and lateral shin)
What are the S/S of Mc-Cune Albright syndrome?
Cafe-au-lait spots
Endocrine issues (precocious puberty, hyperthyroid, etc)
Fibrous Dysplasia (i.e. osteolytic looking lesions of bones)
What is the pathogenesis of McCune-Albright Syndrome?
Mosaic somatic mutation in GNAS (encodes stim alpha subunit of G protein)
This causes continuous activation of adenylate cylcase–>overproduction of certain hormones
What is Legg-Calve-Perthes disease?
Idiopathic avascular necrosis of the femoral head ossification center. Usually in young boys.
Presents with pain in knee or a limp.
What two markers are elevated in neural tube defects on amniocentesis?
alpha fetoprotein and acetylcholinesterase
Birbeck granules are characteristic of what cell type?
Langerhans cells
These are the dendritic cells of the skin (antigen presenting cells)
How is Isoniazid metabolized?
Acetylated to N-acetyl-isoniazid in the liver by N-acetyl transferase
What antivirals are nucleotide analogs? (2)
Cidofovir
Tenofovir
What antivirals are nucleosides and therefore must be phosphorylated to function?
Acyclovir
Valacyclovir
Famciclovir
Ganciclovir
On a jugular venous pulse wave tracing, what do the a, c, and x waves represent?
a=Right atrial contraction
c=tricuspid valve bulging during RV contraction
x=right atrial relaxation
On a jugular venous pulse wave tracing, what do the v and y waves represent?
v=inflow of venous blood
y=passive emptying of RA into RV
When obtaining a sexual history, how should you ask about their sexual orientation?
Ask what genders their partners have been, or both
What is the most common secondary malignancy that occurs in familial retinoblastoma?
Osteosarcoma
3-5 days of fever followed by truncal blanching maculopapular rash (maybe spreading to face and extremities) (+/- seizures), think?
Roseola infantum
Caused by HHV-6
Paranasal fungal infections: bug and histology (3)
Aspergillus (NARROW angle, septate hyphae)
Mucor (broad, ribbon-shaped non-septate hyphae branching at wide angle)
Rhizopus (broad, ribbon-shaped non-septate hyphae branching at wide angles)
What is the function of atrial natriuretic peptide?
Peripheral vasodilation
Natriuresis
Diuresis
If someone aspirates while supine, where will the aspirated fluid go?
To the POSTERIOR part of the lung.
This will usually be the posterior lower lobe, and posterior UPPER lobe.
Describe the natural process of insulin release
Glucose xported in vial GLUT2 Via metabolism, glucose–>ATP
inc ATP–>closure of ATP dependent K+ channel
Depolarization of membrane Influx of calcium–>insulin release
How do you treat pinworm infx (enterobius vermicularis)?
Albendazole or pyrantel pamoate
What two types of anxiety disorders are differentiated by timeline?
Acute Stress disorder and Post-traumatic Stress Disorder (3 days to 1 month vs over 1 month)
What do HOX genes encode?
Transcription factors
These factors bind DNA, and alter gene expression–>segmental patterning
What metabolic enzyme needs N-acetylglutamate as an allosteric activator?
Carbamoyl phosphate synthetase I
What molecule is needed as an allosteric activator of carbamoyl phosphate synethtase I?
N-acetylglutamate
What does Smith protein normally complex with?
small nuclear RNA (snRNA)–>small nuclear ribonucleoproteins (snRNPs)
snRNPs help form spliceosomes–>intron splicing
What is the function of small nuclear ribonucleoproteins (snRNPs)?
Spliceosome formation–>intron splicing
List some differences b/t right and left sided frontal lobe lesions:
Left sided: apathy and depression
Right sided: disinhibited behavior
Where is proinsulin cleaved to give insulin and c-peptide?
Inside secretory granules by endopeptidases
How to differentiate mastitis from inflammatory breast CA?
Mastitis will have systemic symptoms (fever) and longer duration.
Inflammatory breast CA may not have an underlying mass assoc
What are the Class III antiarrhythmics?
Sotalol
Amiodarone
Dofetilide
Ibutilide
What class of drug is Dofetilide?
Class III antiarrhythmic
What is the mechanism of action of aminoglycosides?
inhibit the 30s bacterial ribosome–>dec translation of mRNA into protein.
During appendectomy, dmg to what nerve would lead to loss of sensation above the pubis?
Iliohypgastric n (L1), anterior branch.
Posterior branch inn gluteal region
What is negative predictive value?
Probability of being disease free if test result is negative.
What type of pattern is seen in the inheritance of autosomal recessive conditions?
Disease not present in consecutive generations
What conditions have polygenic inheritance? (7)
- Androgenetic alopecia
- Epilepsy
- Glaucoma
- HTN
- Ischemic Heart Disease
- Schizophrenia
- Type II Diabetes
Give the defining microbiologic features of bacteroides
Gram Negative, anaerobic
Can produce Beta lactamase
Treat with penicillin plus beta lactamase inhibitor
What antibiotics can be used for anaerobic bacteria?
Piperacillin w/tazobactam (extended spectrum penicillin)
Metronidazole (below the diaphragm)
Carbapenems
Clindamycin (most of the time, also for infx above diaphragm)
What type of receptor controls the secretion of PTH?
Calcium-sensing receptors (CaSR) are a G-protein receptor.
Calcium binding to CaSR–| PTH release
Dec binding to CaSR–>inc PTH release
What signaling pathway does PTH use?
cAMP
What is ornithine?
An amino acid that is produced during the last step of the urea cycle (arginine splits into urea and ornithine).
Then used as the first substrate to produce citrulline with carbamoyl phosphate
Where is an anal fissure most likely to present, especially if chronic?
Posterior midline, distal to dentate line if painful.
D/t poor perfusion of the posterior anal canal.
What is Parinaud Syndrome (dorsal midbrain syndrome)?
Paralysis of upward gaze
Ptosis
Pupillary abnormalities
D/t direct compression of pretectal region of midbrain (pineal gland tumor)
What does bradycardia in an MI indicate?
Damage to the sinus node, likely due to RCA involvement
What nerve innervates the tensor tympani?
V3 (mandibular branch of trigeminal)
What causes angioedema?
Accumulation of bradykinin
Can take weeks or months if being caused by a medication (ACE-I)
Why is methadone effective in treating heroin addiction?
It has a very long half life.
Full mu-opiod receptor agonist
Besides gallstones and alcohol, what is another cause of acute pancreatitis?
Very high serum triglycerides can cause direct injury to pancreatic acinar cells.
What are the less common causes of acute pancreatitis? (7)
Recent ERCP
Drugs (azathioprine, furosemide, valproate, sulfasalazine)
Infx (mumps, Coxsackie, mycloplasma)
Hypertricglyceridemia
Anatomic prob of pancreatic duct or ampulla
Surgery
Hypercalcemia
What causes the DIC seen in meningococcal meningitis?
Direct action of lipooligosaccharide on Toll-like receptor 4
What is the mechanism of fibrates–>gallstones?
Fibrates inhibit rate limiting enzyme of bile synthesis, cholesterol 7-alpha-hydroxylase.
This leads to dec bile and inc cholesterol–>precipitation of cholesterol as stones.
What is the anti-tumor mech of IL-2?
IL-2 is a growth factor for T cells. After secretion by activated TH cell, it stim growth of ag-specific CD4 and CD8 T cells.
Also activates NK cells and monocytes and stim growth of B cells.
Anti-tumor activity is due to activation of NK and T cells.
What is the most common fungal pulmonary infection in patients with neutropenic fever?
Aspergillus
In an MI, what is the sequence of healing leading to scar formation?
Inflammatory cells arrive and clean up debris.
Fibroblasts lay down type III collagen
2 weeks post infaction, type I collagen replaces type III.
At what point in the PFT curve is the vascular resistance in alveolar and extra-alveolar vessels the least?
Functional Residual capacity, due to increased tension at extremely high and low lung volumes.
What is a good landmark for locating the appendix?
Convergence of the teniae coli muscles (this occurs at the appendix root)
How does a ristocetin assay work?
Ristocetin activates GP1b on platelets, allowing vWF to bind.
If vWF is low, no/poor aggregation occurs.
Adding normal plasma causes aggregation in vWF Disease but not in Bernard-Soulier.
Leads to dgs of vWF deficiency.
What molecule is the precursor to the target for SSRIs?
Tryptophan
What is the treatment for serotonin syndrome?
What is that med’s MoA?
Cyproheptadine
1st Gen antihistamine that also blocks 5HT1 and 2
What is DRESS Syndrome?
“Drug rash w/eosinophilia and systemic symptoms”
Fever
Generalized Lymphadenopathy
Facial Edema
Diffuse morbilliform skin rash
Also can affect organs: liver, kidney and lung
What are the causes of DRESS Syndrome and what do labs show?
Caused 2-8 weeks after drug exposure:
Anticonvulsants (phenytoin, fosphenytoin)
Allopurinol
Sulfonamides
Antibiotics (minocycline, vanco)
Labs:
Eosinophilia
Atypical lymphocytosis
inc seurm ALT
What is an indication for statin therapy?
Post-MI, no matter what the lipid levels actually are
Where is the DNA that encodes rRNA formed?
Nucleolus
So RNA Pol I is active at the nucleolus
What is the other function of myelination, besides increasing conduction velocity?
Reducing charge dissipation–>inc distance impulse can travel
This increases membrane resistance–>inc length constant
How does myelination inc conduction velocity?
Dec membrane capacitance
This dec time constant–>more rapid membrane potential changes
What fibers transmit pain and temperature sensation?
Where are they located in the spinal cord?
Spinothalamic tract fibers
1st order in DRG, then 2nd order through dorsal horn ,decussate at anterior white commissure and ascend in opposite lateral funiculus
3rd order bodies are in VPL nucleus of thalamus
4th order in parietal lobe somatosensory cortex
What is the Number Needed to harm?
Number treated before adverse event occurs
NNH=1/Attributable Risk
Attributable Risk=Event rate(tx)-Event rate(placebo)
What is an Aschoff body?
What does it indicate?
Interstitial myocardial granulma, consisting of lymphocytes, mphages and giant cells
Indicates Acute Rheumatic Fever
What is a cutaneous complication of chronic lymphedema?
Stewart-Treves syndrome aka Cutaneous angiosarcoma
Histo: dermal infiltration w/abnormal vascular spaces resembling slits. Poor prognosis
Why does Hep D need HBV?
HDAg must be coated with Hep B surface Ag to penetrate hepatocyte.
Where are dmged RBCs removed from circulation?
Red pulp of the spleen
What layer does the superficial inguinal ring lie in?
External spermatic fascia (from external oblique)
In what layer does the deep inguinal ring lie?
Transversalis fascia
What lipid lowering medication is best at dec triglycerides?
Fibrates
What is the underlying physiologic mechanism for Niacin’s side effects of flushing, warmth and itching?
Inc PGD2 and PGE2 and other PGs. Pretreat with Aspirin to reduce these
What teratogenic effects does Vitamin A have?
DiGeorge Syndrome like defects:
Craniofacial abnormalities
Posterior Fossa CNS defects
Auditory defects
Great vessel abnormalities
What is a cause of caudal regression syndrome?
What is caudal regression syndrome?
Uncontrolled maternal diabetes
Agenesis of sacrum, +/-lumbar spine–>flaccid paralysis of legs, urinary incontinence, and dorsiflexed contractures of feet
How does Shigella primarily cause dysentary?
Invasion of the mucosa. It does produce a toxin on occasion but this isn’t necessary for virulence.
How to differentiate Chronic Myelogenous Leukemia and Leukemoid Reactions?
CML will have a low alk phos
Leukemoid will have normal or elevated alk phos
How to interpret Weber and Rinne tests?
Rinne: If pt hears the sound better on the bone than in the air this is conductive hearing loss (a negative (-) Rinne Test)
Weber: If Rinne test is (-) then the sound should lateralize to the bad ear. If Rinne is normal, then the Weber lateralizes to the good ear.
How can you tell the difference between phenotype mixing and reassortment in influenza viruses?
Phenotypic mixing will not have progeny with the new trait
Reassortment progeny will contain the new trait
How is an annular pancreas formed?
Pancreas divisum?
Annular pancreas occurs when the ventral pancreatic bud does not migrate properly
Divisum occurs due to a failure of fusion b/t ventral and dorsal buds
What is the function of BRCA1?
DNA repair
What is the function of KRAS?
Proto-oncogene. Activation and overstim–>neoplasms
How do osteocytes (mature osteoblasts) connect to each other?
Via gap junctions to allow communication
What enzymatic activities is Thiamine vital for?
Pyruvate dehydrogenase (pyruvate–>acetyl CoA)
alpha-Ketoglutarate dehydrogenase (alpha-ketoglutarate–>succinyl-CoA)
Branched chain amino acid dehydrogenase (b/d of leucine, isoleucine, valine)
Transketolase (converts ribulose 5-P to G3P)
In regards to a pregnant minor, what can they consent to if unemancipated?
Emergency Care
STI tx and dgs
Substance abuse (most states)
Prenatal Care (most states)
How does Fabry Disease present?
In adolescence:
Neuropathic pain
Hypohydrosis (dec sweating)
(both d/t loss of small-fiver nerves in distal extremities)
Proceeds to:
Angiokeratomas (dark red, non-blanching macules in clusters over buttocks, groin and umbilicus)
Telangiectasias
Early/Mid Adulthood:
Cerebro and Cardio Vascular Disease
Buildup of the metabolite (globotriaosylceramide) leads to proteinuria and polyuria–>renal failure.
What is the enzyme deficient in Fabry Disease?
What product builds up?
alpha-galactosidase A
Globotriaosylceramide (Gb3)
What is the function of neuraminidase?
Release virion particles from infected cells
What is delayed diagnosis a type of?
Type of preventable medical error
What can present with hemoperitoneum and left shoulder pain?
Splenic laceration/rupture (Kehr’s sign is the shoulder pain)
What is characteristic of Fibroadenoma on histo?
Benign-appearing cellular/myxoid stroma around epithelial lined glandular and cystic spaces
What are the TORCH infections
T:Toxo (protozoan)
O: Other-VZV (dsDNA virus), Parvo (ssDNA), Syphilis (spirochete)
R: Rubella (ssRNA)
C: CMV (dsDNA)
H: HSV (dsDNA)
What kind of congenital abnormality does Parvovirus cause? Why?
VZV?
Hydrops Fetalis, inhibits erythropoeisis–>anemia–>hydrops
VZV:
Limb hypoplasia
Cutaneous scarring
Cataracts
Chorioretinitis
How does Parvovirus infection present in adults?
Symmetric arthralgias/arthritis with or w/o rash
How do we correct for the sample size when extrapolating the standard deviation to a population?
Divide the SD by sq root of N.
This gives the standard error, which is based on the population, not just sample size.
What medications are indicated for muscle spasticity, secondary to brain and spinal cord disease?
Baclofen (GABA-B agonist)
Tizanidine (alpha 2 adrenergic agonist)
Good in MS
How can IgA nephropathy present?
Acutely: just after a URI with painless hematuria
Chronic: every few months or after another URI get painless hematuria
What ultrasonographic findings are specific for acute cholecystitis?
Gallbladder wall thickening
Pericholecystic fluid
Positive sonographic murphy sign
Echogenic structures in gallbladder are NOT specific for acute cholecystitis
Besides the preferred imaging (ultrasound), what is another test that can diagnose acute cholecystitis?
What would it show?
Radionuclide biliary scan (tracing dye injected IV, processed by liver)
The dye will be excreted into the common bile duct and the small bowel, but won’t be taken up by the gallbladder.
What are the viruses with segmented genomes?
BOAR
Bunyavirus
Orthomyxovirus
Arenavirus
Reovirus
Where is the aorta located anatomically in relation to the pulmonary artery?
Posterior and left
What is RNA interference?
dsDNA given that causes mRNA degradation
How does ion charge affect membrane potential?
Influx of (+) ions increases membrane potential, while an influx of (-) ions causes dec in potential
Where are calmodulin and myosin light chain kinase located?
Smooth muscle cells
In post partum hemorrhage, which artery would you ligate to save the uterus?
Internal Iliac artery
What is the most common position of the arm to cause an anterior shoulder dislocation?
Externally rotated and abducted
What is the histology of polyarteritis nodosa?
Transmural inflammation
What component of peptidoglycan is only found in gram (+) bacteria?
Teichoic acid
How does HBV cause hepatocellular carcinoma?
Integrates into the host genome then produces mutations in proteins
How does Beta thalassemia arise?
Defect in mRNA production of Beta globin chain
What is the difference between porphyrias and thalassemias?
Thalassemias=defects in globin chain synthesis
Porphyrias=defects in heme synthsis
How does SIADH cause hyponatremia?
inc ADH–>inc H2O reabsorp–>inc volume–>dec RAAS activation and
dec production of Natriuretic peptides–>inc Na+ excretion
What effect would would an ACE-I have on a patient in reno-vascular HTN?
Causes Acute Renal Failure
What maintains a PDA?
What are the S/S of a PDA?
PGE2
Tachycardia
Resp Difficulty
Widened pulse pressure
What causes the green color of pus?
Myeloperoxidase from PMNs (MPO is green pigmented)
Define Specificity?
True Neg/(True Neg + False Pos)
Define Sensitivity
True Pos/(True Pos + False Neg)
How does Glucagon affect the heart in Beta blocker OD?
Externally paces the heart via Gs receptors
How do statins and fibrates affect gallstone formation risk?
Statins dec cholesterol synth–>dec cholesterol conc in bile–>dec gallstone risk
Fibrates dec bile acid synth–>dec bile acid in bile–>inc gallstone risk
What cell type covers the true vocal cords?
Stratified squamous epithelium
Differentiate factitious disorder from malingering
Factitious gets no gain from faking illness while malingering gets some personal gain.
What is a cause of Ehlers-Danlos?
Defect in cross-linking collagen via defect in cleavage of terminal propeptides
What type of vaccine is the Rabies vaccine?
Inactivated virus vaccine
What is a consequence of Strep Bovis (gallolyticus) endocarditis?
Can lead to colon cancer
What is the most common complication of IV Drug Abuse?
S. Aureus Endocarditis
How does Primary Adrenal Insufficiency (Addison’s Disease) present?
1st:
Weight Loss
Hyperpigmentation (ACTH inc greatly–>Melanin)
Later:
Sodium Wasting
Potassium retention
What are the S/S of Aortic Regurgitation?
Heart Palpitations
Head Bobbing
Head pounding on exertion
These due to a widened pulse pressure.
Define Pulse Pressure
=Peak systolic-end diastolic
How does Zollinger-Ellison syndrome cause diarrhea?
dec pH from high Gastrin leads to deactivation of intestinal enzymes
What differentiates Phencyclidine (PCP) from Ketamine?
PCP is a NMDA antagonist
Ketamine is an NMDA agonist
What is unique about Flecainide as an antiarrhythmic?
Shows use dependence (as Heart Rate inc, amount of Na+ blocking inc–>inc QRS duration)
What kind of necrosis occurs in the brain from ischemia? Why does this type of necrosis occur?
Liquefactive necrosis
As neurons die, lysosomes spill digestive enzymes–>liquefaction
When can aromatase inhibitors be used for Breast Cancer?
ER (+) Breast Cancer in POST menopausal women
What is the urachus?
Connects the allantois (yolk sac) and the bladder
What are the side effects of Methotrexate?
Primarily in places with rapid cell turnover:
Mucosa (GI upset)
Hair follices (hair loss)
Bone marrow (pancytopenia)
Hepatotoxic
Pulmonary Fibrosis
What are the S/S of Vitamin A toxicity?
N/V
Vertigo
Blurred Vision
Long Term:
Alopecia
Dry Skin
Hepatosplenomegaly
What causes paraneoplastic cerebellar degeneration?
Immune response to tumor cells (anti-Yo, P/Q, Hu) cross reacts with Purkinje cells in cerebellum
What are the S/S of paraneoplastic cerebellar degeneration?
Ataxia in limbs and trunk
Visual disturbances
Dizziness
Dysarthria
In setting of cancer patient
What causes Leukocyte Adhesion Deficiency?
Def in LFA-1 (CD18) Integrin
What is Jervell and Lange-Nielsen Syndrome?
Congenital long QT interval with sensorineural deafness-AR
What does the -cept ending on a med mean?
-nib?
Receptor molecule.
Kinase inhibitor
What is MoA of Etanercept?
Inhibits TNF alpha by being a decoy receptor
How do we dampen loud sounds?
Stapedius muscle reduces stapes mvmt–>dampening of loud sounds.
Stapedius inn by CN VII
How do we dampen sound transmission?
Tensor tympani pulls malleus medially, tensing the tympanic membrane and dampening vibration (sound)
Tensor tympani inn by CN V3
What is the MoA of bisphosphonates?
bind hydroxyapatite sites on bone surfaces–>uptake by osteoclasts.
Inside osteoclasts, inhibits them–>dec bone resportion.
How does the insulin receptor act?
Tyrosine kinase–>PI3K and Ras activation.
PI3K causes translocation of GLUT4.
Ras activates intracellular enzymes–>protein synthesis and anabolism.
How does TNF alpha interact with the insulin receptor?
What other molecules cause this same effect?
TNF alpha activates SERINE kinases–>inactivation of IR substrate 1 (intermediate b/t IR and PIK3/RAS).
Threonine residues
catecholamines
glucagon
glucocorticoids.
What causes the black color of the liver in Dubin-Johnson syndrome?
Accumulation of epinephrine metabolites
What are some metabolic consequences of amphotericin B?
Causes renal toxicity–>Acute Tubular Necrosis–>electrolyte disturbances
What is the pathogenesis of Fragile X?
Accumulation of CGG repeats–>hypermethylation of entire FMR1 gene–>inhibition of FMR1 gene–>Fragile X
What causes Paroxysmal Nocturnal Hemoglubinuria?
Mutation in PIGA gene–>no GPI anchor–>dec CD55(Decay accelerating factor) and CD59(MAC inhibitory protein)–>hemolysis by complement
What is a potentially lethal SE of class III antiarrhythmics?
Prolong QT–>Torsades (less w/amio)
What is the MoA of Adenosine?
A1 receptor activation–>inc K+ conductance–>further dec in membrane potential–>blocks depolarizations
If you want the top 2 Std dev, how would you calculate this from a population?
2 SD is 2.5% above and below (so covers 95%).
But the top 2 SD would be just 2.5%.
What does a lower blood oxygen content mean?
less hemoglobin all else equal
What is the oxygen content of blood?
the CaO2, total oxygen in blood
How is Calcium in myocytes removed?
By a Na+/Ca++ exchanger and a Ca++ ATPase
What are consequences of thiamine deficiency?
Beriberi (dry or wet-high output CHF)
Peripheral Neuropathy
Wernicke’s encephalopathy
Korsakoff syndrome
What is the most common association with an imperforate anus and no other abnormalities?
Urinary tract abnormalities
VACTERL association is much less common
What is the alveolar ventilation equation?
Alv ventilation=(tidal vol-dead space vol)xRR
What are the physiologic parameter derangements in ARDS?
dec lung compliance
normal pulmonary capillary wedge pressure
What is positive predictive value?
True pos/(true pos + false pos)
What is the equation for negative predictive value?
True Neg/(True Neg + False Neg)
What is a severe adverse effect of acyclovir?
Nephrotoxicity when given IV
Prevent with IV hydration
What are some cytokines that cause cachexia?
How does cachexia occur?
TNF alpha
IL-1B
IL-6
TNF alpha–>appetite suppression @ hypothalamus and inc metabolic rate
What causes differentiation of myeloid cells?
IL-3
Besides lactulose, what is another treatment for hepatic encephalopathy?
Rifaximin
What are the MoA of Rifaximin for hepatic encephalopathy?
Lactulose?
Nonabsorbable Abx–>dec intraluminal ammonia produced by altered GI flora
Taken up by GI flora–>catabolized to short chain fatty acids–>dec lumen pH–>conversion of NH3 to NH4+
What is Werdnig-Hoffman disease (spinal muscle atrophy type I)?
Failure of the gene that turns off apoptosis–>neuronal cell death postnatally.
Causes LMN S/S.
No cure, death by age 2 d/t resp failure
How can red man syndrome from Vanco be prevented?
Slow the infusion rate
What property of linezolid can cause serotonin syndrome?
It has MAO-I activity
What is ceterizine?
A 2nd gen antihistamine
How do negative sense, single stranded RNA viruses create their proteins?
Carry an RNA-dependent RNA polymerase in their nucleocapsid to create mRNA.
They then use the host cell’s ribosomes to translate this mRNA.
What often accompanies serum acidosis, esp in DKA?
Hyperkalemia
What could a lesion to the ventral rami of C5, C6 or C7 damage?
Long Thoracic nerve–>loss of inn to serratus anterior–>winging of the scapula
In patients with overactive, urge incontinence, what medications are used?
Antimuscarinic agents:
Tolterodine
Solifenacin succinate
Darifenacin
Oxybutynin
Trospium
Fesoterodine
How can Sarcoidosis present?
Hilar adenopathy (asymptomatic)
erythema nodosum (tender red lesions)
Joint swelling
Also:
Uveitis
Hypercalcemia (mphages in granulomas make 1 alpha hydroxylase–>activated vit D)
inc ACE
Rhabdomyoma, think?
Tuberous Sclerosis
Characterized by benign tumors in multiple organs (brain, heart, skin, eyes, lung, kidney and liver).
What is the classic triad of Tuberous Sclerosis?
Skin Lesions: Ash-leaf spots (hypopigmented macules), Angiofibromas, Shagreen patches
Epilepsy
Cognitive deficits/learning disabilities
What is the pathophysiology of Tuberous Sclerosis?
Usually, TSC1 encodes hamartin and TSC2 encodes tuberin.
Hamartin and tuberin form a complex that inhibits Rheb, by keeping it in GDP bound state.
With mutation in either TSC1 or TSC2, Rheb becomes active.
Rheb acts on mTOR making constitutively active–>uncontrolled cell growth.
What does Zileuton do?
Zafirlukast/montelukast?
Inhibits 5-lipoxygenase–>dec leukotriene synth
Blocks LTD4 receptor. (kasts cast themselves onto the receptor to block it)
What are examples of sulfa drugs? (11 groups)
Zorro Destroys The Dons’ Bullshit Popular FACTTSSSS: Zonisamide (anticonvulsant)
Dofetilide
Topiramate
Dronedarone
Bosentan
Probenecid
Furosemide
Acetazolamide
Celecoxib
Thiazides
Tamsulosin
Sotalol
Sulfa antibiotics (TMP-SMX, sulfadiazine)
Sulfasalazine
Sulfonylureas
What is common in all MHC Class I containing cells?
A nucleus
Therefore, RBCs do not have MHC Class I
What cell mediates cytotoxicity in malarial infections?
Natural Killer (NK) cells
RBCs do not have a nucleus, and no MHC Class I, therefore cytotoxic T cells cannot interact and kill infected RBCs.
NK cells identify their targets by lack of MHC Class I, so they can kill malaria infected RBCs.
With persistent truncus arteriosus, what other cardiac defect MUST be present?
Ventricular Septal Defect.
Failure of the AP septum to form won’t allow the septum to close b/t LV and RV.
What causes the rising estrogen in the follicular phase of menstrual cycle?
Granulosa cell proliferation in the ovarian follicle that is maturing.
Aromatase converts testosterone to estrogen in the granulosa cells.
What is the Swiss Cheese Model of failure analysis?
How can it be applied?
Many small failures occurred, leading to the actual hazard.
Apply it to try to reduce both active and latent failures. Reduce the chance that a failure would occur in multiple layers to stop progression to a catastrophic failure.
Why is blockage of the middle cerebral artery so devestating?
No anastomosis as it isn’t part of Circle of Willis
How are complications of B. pertussis caused?
What are they? (4)
The AB Pertussis toxin ADP ribosylates Gi. This causes inc cAMP–>complications:
Hypoglycemia (inc insulin prod)
Lymphocytosis
Immune effector cell inhibition
Histamine sensitivity
How do blood levels of PO2, CO2 and pH compare to atmospheric levels?
PO2 is lower in blood
PCO2 is higher in blood
air doesn’t have pH, but exposure to ambient air of an arterial sample–>inc pH
What is cholecalciferol?
Vitamin D3
What is the piriform cortex?
Primary olfactory cortex, aka uncus
What is the method of detecting cryptococcus?
Latex agglutination test
India Ink stain is outdated now
Carboxylases, what vitamin cofactor?
Dehydrogenases and transketolases, what vitamin cofactor?
Biotin
Thiamine (via TPP)
(also dehydrogenases use CoA (pantothenate/B5), lipoic acid, FADH2 (riboflavin/B2), and NADH (niacin/B3))
TLC For Nobody
Bioavailability (F)=
(area under oral curve*IV dose)/(area under IV curve*oral dose)
What is the cause of lymphogranuloma venerum?
Chlamydia serotypes L1-L3
Hairy Cell Leukemia S/S:
Bone marrow failure (pancytopenia/dry tap)
Splenomegaly
Recurrent Infx
Systemic Mastocytosis S/S
Itching after a shower (compare to polycythemia vera)
Mast cell proliferation in the skin
Inc gastric acid secretion (excess mast cell activation–>histamine release–>inc H+)
What med is best for restoring fertility in PCOS?
Clomiphene
MOA: Selective Estrogen Receptor Modulator (SERM) at hypothalamus
Where is the piriform recess?
What is it’s function?
Just lateral to the epiglottis. Overlies the internal laryngeal nerve.
Afferent part of the cough reflex.
Infx in burn patient. Think?
Medication to treat? (Big list)
Pseudomonas
Cefepime
Ceftazidime
Ticarcillin
Pipercillin
Amikacin
Gentamicin
Tobramycin
Cipro/levofloxacin
Aztreonam
Imipenem/Meropenem
What mood stabilizers good for bipolar disorder and seizures
Valproate
Carbamazepine
Lamotrigine
Underlying mechanism of gingival hyperplasia with Phenytoin use:
inc PDGF–>inc gingival fibroblast activation–>inc gingival density and cell population
What does normal cardiac aging entail?
dec LV volume
Sigmoid shaped septum
Lipofuscin deposition
What is kinesin’s function?
Moves vesicles along microtubules using ATP in a anterograde direction.
(it kicks the kan down the road)
What are the strictly ketogenic amino acids?
Which amino acids are glucogenic and ketogenic?
Leucine and Lysine
Phenylalanine, Isoleucine, and Tryptophan
All others are glucogenic only
What is unique about RBC metabolism?
Can only use glucose for energy. Not able to use ketones.
How is metabolism of RBCs and liver cells similar?
Neither can use ketones. Liver cells lack thiophorase (aka succinyl CoA acetoacetate CoA transferase)
What is a severe side effect of subarachnoid hemorrhage?
Treatment for this side effect?
Vasospasm
Give nimodipine, a cerebral selective calcium channel blocker
What is the mechanism of Toxic Shock syndrome?
What are the S/S of TSS?
TSST (toxic shock syndrome toxin) crosslinks mphages and THelper cells–>IL-2 prod from TH cells and IL-1 and TNF from mphages
This leads to the S/S of Toxic Shock Syndrome:
Fever
Rash
N/V
Desquamation
Shock
How does the chromosomal abnormality in Klinefelter syndrome occur?
Meiotic Nondysjunction
Increasing number of X chromosomes=inc severity
Where is rRNA synthesized?
Nucleolus
5.8s rRNA is exception: synth in nucleoplasm
Clearance=
(0.7*Vd)/(t^1/2)
What amino acids are abundant in keratin?
Alanine, glycine, cysteine
Inc strength
What type of receptor is HER2/NEU?
What is its function?
Its molecular weight?
It is an epidermal growth factor receptor with a tyrosine kinase
Activation leads to cell proliferation.
Weight=185 kD
What is synaptophysin?
Transmembrane glycoprotein that indicates neuronal origin
What cells stain GFAP positive?
Astrocytes
Oligodendrocytes
Ependymal cells
What is the Fick principle?
Cardiac Output (CO)=O2 consumption/(art O2 content-venous O2 content)
