UWorld first half Flashcards

Question

Temporary local hyperoxia (like seen in a premature infant given high doses of O2) results in what?

Answer 1

-Can induce VEGF in the retina resulting in neovascularizaion =retinopathy of prematurity

Answer 2

1. aPTT: unfractionated heparin 2. PT: Warfarin (WEPT) 3. Bleeding Time: assessment of platelet function, would be increased in vWd, ASA therapy, DIC, 4. Fibrinogen Levels: would be low in DIC 5 Fibrin Split Products, would be low in DIC

Answer 3

- when it infects B-cells via CD21, it stimulates them to enter the cell cycle and proliferate continuously **(IMMORTAL**). This happens by an EBV encoded oncogene activating proliferative and anti-apoptotic signaling pathways within the infected B-cell. - Keep in mind the dx of EBV is the production of heterophile antibodies (meaning react with foreign antigen such as hoarse erythrocytes

Answer 4

**Restrictive Lung Disease:** Decreased FEV1 but MORE of a decrease FVC leading to an INCREASE IN THE RATIO. Decreased TLC "Restrictive Raise" **Obstructive:** Decreased FVC but decreased MORE the FEV1 leading to a DECREASE IN THE RATIO. Increased TLC as well. "Obstructive is Obsolete"

Answer 5

**-HYPOnatremic** - They are salt wasting from sweat because sodium is NOT reabsorbed through the CFTR due to a mutation (deltaF508) - Risk factors for a CF pt would be excessive temperature, excessive exercise and the newborn period when they are solely on breastmilk and not eating salty foods yet (all pre-dispose to hyponatremia) - NOTE, these pts are also **HYPOCHLOREMIC**, but this is **asymptomatic**.

Answer 6

- Succinyl CoA --\> Succinate (near the bottom of the circle) - This is called substrate level phosphorylation and is carried out by the enzyme Succinyl CoA synthase - The GTP is then a cofactor for PEP-CK in gluconeogenesis going from oxaloacetate to PEP.

Answer 7

**-Leukocyte Adhesion Deficiency (LAD)**. Defect in LFA1 integrin on CD18, leading to impaired migration and chemotaxis. **CANNOT form integrins**, which are essential for leukocyte adhesion -presents with recurring skin and mucosal infections, and periodontal disease Also see late separation of **umbilical cord (\>21 days)**

Answer 8

- Erythrocytes escape into interstitum after injury and give blue/purple color - Erythrocyte destruction then causes release of heme molecules **HEME OXYGENASE** comes along (inside macrophages) and converts Heme--\>Billiverdin (which is green in color) The Billiverdin is then further broken down to billirubin (yellow) and is then bound to albumin and taken to liver

Answer 9

1. PCN --\> beta-lactamase, mutated PBP, mutated porin protein 2. Vancomycin --\> mutated peptidoglycan cell wall (d-ala, d-lac) 3. Quinolones --\> Mutated DNA gyrase, impaired influx/efflux 4. Aminoglycosides --\> bacterial transferase enzymes that acetylate, adenylate, or phosphorylate 5. Tetracyclines --\> influx/efflux 6. Rifamycin --\> mutated RNA polymerase

Answer 10

Congenital degeneraton of anterior horns of spinal cord. LMN lesions resulting in "**floppy baby"** with marked hypotonia. - Caused by mutations in **SMN1** gene which involves assembly of small nuclear ribonucleoproteins **snRNP.** - impaired **SPLICESOME** fxn (removes introns from pre-mRNA)

Answer 11

**1. Infliximab**: IgG1 monoclonal antibody against TNFalpha. Use in RA, AS, Crohns **2. Rituximab:** targets CD20 B-cells used in lymphoma **3. Interleukin 2:** cytokine that regulates activation and differentiation of T-cells. Use in Renal Cell Carcinoma and Melanoma **4. Imatinib:** tyrosine kinase inhibitor used in CML **5. Abciximab:** against platelet GP11B/IIIa receptor, used during angioplasty for pts with ACS

Answer 12

Inspissated mass (dehydrated meconoium) in distal ilium points to a diagnosis of **meconium ileus** which is very common in **CF** pts. - If you habe meconium ileus you will almost certainly be diagnosed with CF but if you have CF only about 10-20% of infants will have meconoim ileus - Ultimately CF pts usually die of **pneumonia** (or cor pulmonale, bronchiectasis)

Answer 13

Vitamin K and Vitamin D -The **Vitamin K** is supplemented by a shot at birth **-Vitamin D** is usually supplemented by some sunlight (harder to get in AA babies because of an increase in melanocytes acting as a natural sunblock) **"KD for the KiD"**

Answer 14

- Die from **pancarditis** (inflammation of the endocardium, myocardium, and pericardium) - Inflammation of the mitral valve is also common and will result in a holosystolic murmur - Severe regurgitation and myocarditis can lead to cardiac dilation, cardiac failure and DEATH in a very small number of pts - Pt will **NOT die of septic shock** from the S. aureus because the disease itself of rheumatic fever with migratory arthritis is autoimmune and NOT caused by the bacteria at this point.

Answer 15

-an acute viral or bacterial infection of the parotid gland **-S. Aureus** is the most common cause. -Risk factors include dehydration, **intubation**, **anticholinergics**, salivary **calculi**, or recent teeth cleaning Dx: **AMYLASE**, US/CT -Think about this in a pt who has acute jaw pain post intubation in a hospital

Answer 16

-Metronidazole or Clindamycin Dx: grey or clear discharge with fishy smell. Use KOH to increase the smell "Whiff Test" -Also dx with presence of CLUE CELLS

Answer 17

1. Decreased maternal serum AFP 2. Increased nuchal translucency 3. Increased b-hCG It is then confirmed by chorionic villus sampling or amniocentesis

Answer 18

when the wall of the terminal ilium is inflamed, bile acids are not reabsorbed. This loss of bile acid reabsorption causes an decrease in fat absorption. These excess lipids in the bowel bind to calcium essentially performing a supponification reaction and these soap complexes are lost in the feces -As a result, oxalate cannot be bound by calcium (like it noramally is) and is taken up in the bowel. This leads to an increase risk of kideny stones

Answer 19

- A newer agent of the halothane class that is used for anesthetics and can lead to acute hepatitis. - It is associated with a centrilobular hepatic necrosis - Presents 2-3 days after exposure with fever, nausea, jaundice, scleral icterus, and increased liver enzymes

Answer 20

12-24 hours --\> "**Red Neurons"** (eosinophilic cytoplasm, **loss of nissel substance**) 24-72 hours --\> neutrophilic infiltration 3-7 days --\> macrophage/microglia infiltration and phagocytosis begin 1-2 weeks --\> reactive gliosis and vascular proliferation around the necrotic area **(liquefactive necrosis)** \> 2 weeks --\> glial scar formation

Answer 21

- intense mononuclear infiltrate consisting of lymphocytes and plasma cells often with germinal centers. - Hurthle cells surround residual follicles

Answer 22

**-DiGeorge Syndrome**, neural crest cells fail to migrate into the **3rd and 4th pharyngeal pouches.** Consequently end up with parathyroid and thymus hypoplasia. This results in **hypocalcemia** and **T cell deficiency** **-**The hypocalcemia manifests as Chovstek and Troussou sign

Answer 23

Failure of the anterior neuropore to close (can be prevented with folic acid supplementation during pregnacy)

Answer 24

-**Craniopharyngioma** resulting in hypopituitarism, hydrocephalus and diabetes insipitus

Answer 25

- Pt is clearly on a statin, an HMG coA Reductase inhibitor and is having stain-induced myopathy - Statins block conversion from HMG CoA --\> Mevalonic Acid, this decrease liver cholesterol leads to an increase in LDL clearance by the liver by LDL receptors. These LDL receptors endocytose the LDL and then are recycled for use again also causes an upregaultion of HMG CoA reductase enzyme since it is all being blocked!

Answer 26

Innervated by **Thoracodorsal Nerve** (from C6-C8 nerve roots) Actions: **Internal rotation of arm**, extension, adduction of arm A very vulnerable muscle to external injury

Answer 27

**-Omalizumab** is an IgG monoclonal antibody that binds with IgE to inhibit the action of IgE on mast cells, basophils, or other cell types and decreases allergic response. (**anti IgE antibody**)

Answer 28

**SGLUT-2 Inhibitor used for TII DM** Usually SGLUT-2 reabsorbs 90% of glucose from filtrate in the proximal tubule. This drug leads to significant loss of urine glucose Side effects: UTI's (due to lots of glucose in urine feeding bacteria), systemic hypotension. Should be avoided in pts with moderate to severe renal impairment **-MUST CHECK RENAL FUNCTION PRIOR TO USE**

Answer 29

**1. Nondisjunction (95%):** extra chromosome 21 in **EVERY** cell, due to increased **MATERNAL** age 2. Unbalanced translocation (2-3%): all or part of additional chromosome 21 attached to another chromosome 3. Mosaicism (\<2%): the nondisjunction event occured early on and the pt has two disctinct cell lines in their body. The proportion of cells affected are what determines severity of disease

Answer 30

- a decrease in ACh level due to a **DEFICIENCY** of **choline acetyltransferase**. This is most notable in the **basal nucleus of Mynert,** which participates in memory and cognition. ALSO involves hippocampus which is obviously involved in new memory formation - AChE-I are meds used to treat Alz =**Donepezil, Galantamine**

Answer 31

Isoniazid 1. Slow acetylation: convert drug slowly and result in an increase in the plasma concentration...also happens with **Dapsone, Hydralazine, and Procainamide** **2.** Fast acetylation:may require higher dose to achieve same therapeutic effect

Answer 32

- STOP SMOKING - this is more of an effect than diet or exercise (these effect cardiovascular health but smoking has profound effect on so many different systems in the body)

Answer 33

Surgery removed parathyroid as well and now the pt is not reabsorbing the calcium in the kidneys anymore This is called symptomatic hypoparathyroidism due to inadvertant removal of parathyroid -phosphate reabsorption would also be decreased in these pts

Answer 34

- **Fabry**, (XL-R) results in buildup of Gb3 - neuropathic pain, and hypohydrosis are the first sx Can also see CVA, CVD which are obviously most common cause of death telangectasia later on The buildup of Gb3 reuslts in proteinuria and polyuria and eventual **RENAL FAILURE**

Answer 35

Pilli E.Coli

Answer 36

- Beta adrenergic agonist (produce relaxation of bronchial smooth muscle by stimulating beta-2 adrenergic receptor) - This acts via Gs --\> increase cAMP - Asthma and COPD are the most frequent causes of pulsus paradoxus in the absence of signficant pericardial disease

Answer 37

This tumor is affecting the zona gomerulosa which produces aldosterone. Aldosterone acts on the distal collecting duct (principal cells) to increase the absorption of Na and dump out K and H. This if a tumor were producing too much Aldo, you would see a hypokalemic, metabolic alkalosis. These would lead to **parasthesias and muscle weakness** **This mimics Conn Syndrome**

Answer 38

L atrial appendage

Answer 39

-caused by uninhibited bladder contractions (detrusor instability). Causes a sense of urgency and involuntary leakage Best treatment is with anticholinergic drugs = oxybutynin, which antagonizes M3 receptors on bladder

Answer 40

**Vasodilators**: (CCB, nitro, ACE-I) lead to decreased afterload and lower LV volumes **Diuretics**: decrease LV filling (preload) and result in greater outflow obstruction

Answer 41

- slow progressive disease caused by the gram + anaerobic bacteria Actinomyces Isralii - usually colonize mouth, colon and vagina and can be found in dental caries - Most frequently presents with cervicofacial abscesses - Pulm actinomycosis is rare but usually occurs because of aspiration. Dx: filamentous branching, sulfur granules Tx: PCN

Answer 42

-Interchin cross-links involving **LYSINE** made by lysyl oxidase (requires Copper as a cofactor). This forms desmosine cross-links between elastin monomers Disulfide bridges are made in **COLLAGEN NOT ELASTIN** **Elastin is made in Alveolar Macrophages**

Answer 43

- Stimulate hypoglossal nerve (causes tongue to move forward slightly) - CPAP - surgery - wt loss

Answer 44

-anticholinergic agent used for acute asthma attacks that blocks muscarinic receptors (M3), preventing bronchoconstriction Side effect is increased drying

Answer 45

1. Nontypeable are unencapsulated and are the cause of MOST mucosal infections (otitis media, conjunctivitis, bronchitis) 90% of strains isolated from the middle ears of children are this type 2. H. Influenza Type B (Hib) are responsible for the other 10% of infections. These are capsulated and there is a VACCINE for this type All children should get this vaccine by 2 months of age to help protect from EMOP (epiglottitis, meningitis, otitis media, and pneumonia)

Answer 46

-Hyperventilation leading to hypocapnia, which can cause decreased cerebral perfusion and altered mental status

Answer 47

- Legionnaire's Disease - one of the most common causes of community acquired pneumonia - commonly contaminates water sources such as tap water, air conditioners, or other water based cooling systems tx: floroquinolones and macrolides

Answer 48

1. Congestion (first 24 hours): area is red, heavy, boggy. Alveolar exudate contains mostly bacteria 2. Red hepatization (days 2-3): Red, firm lobe (liver like consistency) Erythrocytes, neutrophils and fibrin present 3. Grey Hepatization (days 4-6): Gray-brown firm lobe. RBC disintegrate, 4. Resolution: restoration of normal architecture

Answer 49

**-Left sided heart failure** -The extra fluid increases resistance to movement and can lead to **decreased lung compliance** resulting in poor gas exchange and shortness of breath. Other causes of reduced compliance include pulmonary fibrosis and insufficienct surfactant

Answer 50

SaO2 \< 92% PaO2 \< 65 mmHG This is a chronic process, would result in an increase RBC mass (increase retic count) due to increase EPO

Answer 51

- Men \>52% Hct - Women \>48% Hct Then need to differentiate if it is an absolute increase or a relative increase --\> need to measure RBC mass (not just Hgb and Hct). If RBC mass is normal, indicates a plasma constriction and relative increase in Hct. If the mass is elevated, must differentiate between Primary and Secondary erythrocytosis by EPO levels (primary have low EPO (myeloproliferative disorder)) (secondary is due to chronic hypoxia from altitude, smoking, COPD)

Answer 52

1. use a spacer 2. Rinse mouth out If get too much residual glucocorticoid in the mouth can predispose to Candida infection

Answer 53

Most susceptible to Catalase + organisms. CGD is missing **NADPH oxidase complex,** which produces superoxide, hydroxyl radicals, and hydrogen peroxide. Pts are susceptible to: **S. Aureus** **Burkholderia** **Serratia** **Nocardia** **Aspergillus**

Answer 54

-Deficiency in myophosphorylase NO rise in blood lactate levels after exercise Decrease in this enzyme results in poor exercise tolerance, muscle cramps, rhabdomyolysis -Can be tolerated by drinking glucose drinks DURING exercise. Not a tx

Answer 55

-They are defienct in fat absorption, thus are defieient in ADEK vitamins, thus are more prone to life-threatening bleeding (esp from the lack of Vit K...making 2,5,7,9,C,S)

Answer 56

-Trauma to stereociliated hair cells in the **organ of corti.** High frequency hearing is lost first Remember: 1. Hearing frequency at **auditory** **nerve** is more likely **schwannoma** 2. Cochlear **Cupula** is responsible for **low** **frequency** sounds 3. Defects of middle ear bones (**otosclerosis**) affects **AIR** conduction over ALL frequencies 4. Malformation of **ROUND** window is more likely **congenital** 5. Rupture of **tympanic membrane** causes unilateral **conductive** hearing loss

Answer 57

Bone marrow diseases caused by overproduction of myeloid cells 1. Chronic Myelogenous Leukemia (BCR-ABL 9;22): **leukocytosis with LEFT shift** 2. Essential Thrombocytosis (JAK-STAT): **thrombocytosis** 3. Polycythemia Vera (JAK-STAT): **erythrocytosis** **4. Primary Myelofibrosis (JAK-STAT):** atypical megakaryotipic hyperplasia, which stimulates fibroblast production which results in progressive replacement of bone marrow by collagen deposition. **BONE MARROW FIBROSIS, SEVERE FATIGUE, HEPATOSPLENOMEGALY**

Answer 58

3 VHL, Renal Cell Carcinoma 4: ADPKD (w/ PKD2), Huntington 5: Cru-du-Chat, Familial adenomatous polyposis 7: CF 9: Fredreich Ataxia 11: Wilms tumor 13: Patau, Wilson's 15: Prader Willi, Angelman 17: NF1 18: Edwards 21: Down 22: NF2, DiGeorge X: Fragile X, X-linked Aggamaglobulinemia, Klinefelter

Answer 59

-Isoleucine, Leucine, Valine Due to branched chain alpha-ketocacid dehydrogenase complex (BCKDC) **Requires thiamine B1 as a coenzyme\*\***

Answer 60

Antrum of stomach (where there are the fewest acid secreting parietal cells)

Answer 61

polysaccharide capsule (prevents phagocytosis) - this capsule is antigenic and Ab are created against it which confers immunity against that particular strain - the pneumococcal vaccine confers generates immunity against some common strains (capsule specific)

Answer 62

**Th1** **IL-2** **INF-Y** Terminal ilium is the most common location of crohns, has cobblestone appearance. Non-caseating granulomas and an inflammatory infiltrate that involves all layers of the wall (transmural) is common **Th2 are more involved in UC!!**

Answer 63

-E. Coli 0157:H7 due to production of Shiga-like toxin (so obviously can see this in Shigella TOO) HUS: thrombocytopenia, renal insufficiency, microangiopathic hemolytic anemia

Answer 64

-Has a prediliction for stratified squamous epithelium In the respiratory tract, the only stratified squamous is the **TRUE VOCAL FOLDS** (think about the constant beating these cells take and they need to be replaced frequently) False vocal folds, paranasal sinus, trachea: **pseudostratified columnar** to help protect from foreign bodies **alveoli: simple squamous** **"It would truly suck to get HPV in the throat"**

Answer 65

Majority of area around ear is **great auricular nerve (anterior) and great occipital nerve (posterior)** ALTHOUGH, the posterior part of the external auditory canal is innervated by small auricular branch of the **VAGUS NERVE** **That little bit right inside your ear that is telling you to go to Vegas**

Answer 66

-Release of LPS from bacterial cells during division or bacteriolysis. LPS is NOT ACTIVELY SECRETED Lipid A is the toxic component of LPS, which causes activation of macrophages leading to widespread release of IL-1 and TNF-alpha

Answer 67

**Low Dose: stilumates D1** receptors to increase RBF, GFR, and sodium excretion. Mesenteric vasodilation occurs at this level **High Dose: stimulate B1 adrenergic** in the heart increaseing pulse pressure, cardiac contractility, and systolic blood pressure **At even higher doses:** stimulates **Alpha-1** to cause systemic vascoconstriction, which results in decreased CO due to increased afterload **(pressor effect)** **DBA looks like DoPA or DOBA**

Answer 68

-Thick fibrous shell that restricts ventricular volumes causes low cardiac output and R sided heart failure **-jugular venous pressure increases** (normally this drops during inspiration due to increase in negative pressure) however in these pts, see a paradoxical rise in jvp **(KUSSMUAL SIGN)** -Can also hear **pericardial knock**, which occurs earlier in diastole than S3.

Answer 69

- IL-6 appears to closely correlate with the severity of the disease - Remember that this temporal arteritis is associated with **polymyalgia rheumatica** and is the most common vasculitis in pts over 50 **Cell mediated process with particular increase in** **IL-6** **Also see increase in ESR**

Answer 70

**Diabetic Nephropathy (for both Type I and Type II)** - The earliest changes are **glomerular basement membrane thickening** with resultant mesangial matrix expansion. Also see **hyaline arteriolosclerosis** (in the intima and media of small arteries and arterioles) - In initial stages, loss of negative charge of GBM leads to **microalbuminemia** Tx: **ACE-I** have been shown to decrease the protein lost in the urine and slow the progression of GBM thickening

Answer 71

-Cauda equina syndrome, which is commonly due to epidural cord compression from a malignancy. Pts usually develop urinary incontinence late in the disease with fecal incontinence as well

Answer 72

**1. Parasite defense:** stimulated by **Il-5** (promotes class switching to IgA) via Th2 and mast cells. The parasite invades the system and is coated in IgE and IgG antibodies that bind the Fc receptors of eosinophils. This triggers release of major basic protein that destroys the parasite. This is an example of **antibody dependent-cell mediated cytotoxicity** **2. Type I hypersensitivity reactions:** eosinophils also synthesize prostaglandins, leukotrienes and cytokines that contribute to **late phase** type 1 hypersensitivity and chronic allergic reactions

Answer 73

- presence of antiphospholipid antobodies in the setting of thromboembolism and reccurent miscarriages - This may be a primary disorder or a disorder secondary to SLE Remember that SLE can present with a false positive RPR/VDRL test and + antiphospholipid antibodies

Answer 74

-a POTENT vasoconstrictor that constricts the efferent arteriole and restores GFR

Answer 75

-MEDULLARY segment of the collecting duct and CORTICAL segment **Medullary**: production of maximally concentrated urine since this region deals with the HIGHEST osmolarity in the kidney **Cortical:** reduces amount of free water delivered to the medulllary collecting duct

Answer 76

-LOWERS oncotic pressure and causes interstitial edema due to net plasma filtration

Answer 77

-**Increased** This is an acid buffer in the urine that is used to trap free H+ and keep it so the pH does not lower too much HPO4 and NH3 are the two most important acid buffers in the lumen of the kidney --\>they become H2PO4 and NH4 \*\*NH3 is the more important of these two as the kidney can greatly increase NH3 production in chronic acidosis\*\*\*

Answer 78

**FF=GFR/RPF** This is the fraction of plasma flowing through the glomeruli that is filtered across the glomerular capillaries into Bowman's Space **RPF can be determined using the PAH** clearance as almost ALL of the PAH is excreted in the urine. **GFR can be estimated by looking at how much creatinine** because this is freely filtered (could use inulin also) The clearance of anything can be calculated as **Cs=(urine concentration x urine flow rate)/plasma concentration** **Note: that 20% is a normal FF for healthy ppl**

Answer 79

- Leads to TOXIC, acute tubular necrosis with vacuolar degeneration and ballooning of the proximal tubular cells - Would find high ANION GAP METABOLIC ACIDOSIS - Calcium oxalate crystals in the urine

Answer 80

-The principle cells of the collecting duct is where lithium can induce diabetes insipitus as a result of lithium's antagonizing effects on the action of vasopressin

Answer 81

Seen in Membranous Glomerulopathy 85% of these cases are idiopathic The remaining cases are due to DM, tumors, SLE, gold, penicillamine, NSAIDS, hep B, hep C, malaria, syphilis

Answer 82

Starting with a **decreased GFR** **Decreased 1-25 dihydroxy vitamin D** --\> decreased intesinal Ca absorption Phosphate retention --\> **high serum phosphate** **LOW serum Calcium** **HIGH PTH synthesis** Secondary **HYPERPARATHYROIDISM**

Answer 83

-Paternal Meiotic Nondisjunction The loss of the X-chromosome results in loss of SHOX gene, which is resonsible for long bone growth (reason why pts with Turner have short stature)

Answer 84

**-Suspensory ligament of the ovary** This is what contains the ovarian artery, vein, lymphatics and nerves **\*\*This is the SAME ligament (=infundibulopelvic ligament) that is twisted in ovarian torsion\*\***

Answer 85

1. suspensory ligament of ovary --\> contains ovarian artery (need to cut for removal of ovary) 2. mesosalpinx --\> region of broad ligament below fallopian tubes and does NOT contain artery 3. ovarian ligament --\> connects ovary to side of uterus (NO blood vessels) 4. Round ligament --\> contains artery of Sampson (not really of consequence when removing ovary) 5. Transverse cervical ligament --\> from cervix to lateral fornix of vagina. Uterine artery does course in superior portion but not relevant for ovarian removal

Answer 86

S. Aureus (gram- bacilli too, like E. Coli and GBS but less common) Usually an abortion resulting from any retained products of contraception in the uterine cavity This usually presents as fever, abd pain, uterine tenderness, foul smelling discharge after pregnency termination

Answer 87

Adenomyosis which is the presence of endometrial glandular tissue within the myometrium

Answer 88

-Saline microscopy (wet prep) looking for motile protazoan Usually presents as thin, yellow, mucous discharge that is foul smelling Tx: metronidazole

Answer 89

**Gap junctions** to heighten **myometrial excitation**. Gap junctions consist of aggregated **connexin** proteins that allow passage of ions between myometrial cells

Answer 90

**Kruckenberg Tumo**r with classic histologic feature of **signet ring cells.** These cells appear this way due to a large amount of mucin that displaces the nucleus to the side of the cytoplasm

Answer 91

- The uterine arteries are the main blood supply to the uterus and are brachnes off of the internal iliac artery. **Bilateral ligation of the internal iliac arteries** would stop uterine blood flow and prevent the need for hysterectomy - The uterus has c**ollateral blood flow from the ovarian arteries** so the blood supply will not be completely cut off

Answer 92

This is a cut made from the **posterior vaginal opening to the perineal body** to enlargen the vaginal outlet to facilitate delivery and reduce the risk for severe perineal laceration The external anal sphincter, rectal mucosa, levator ani, ischiocavernosus muscle and transverse perineal muscle are NOT cut

Answer 93

These cells undergo **progesterone withdrawl**, leading to a **prostaglandin increase**, which leads to **vasoconstriction** of the spiral arteries The progesterone withdrawl also leads to increased metalloproteases by endometrial stromal cells leading to **APOPTOSIS** of endometrial epithelium and sloughing of the wall.

Answer 94

- exchange of genetic information between two nonsegmented, double stranded DNA genomes. This is the exchange of genes between two chromosomes via crossing over within homolglogous chromosomes - Unlike Reassortment, which refers to changes in genomic composition that occur when host is coinfected with 2 **SEGMENTED** viruses that echange whole genome segments - The herpes virus is NOT segmented, so it cannot undergo reassortment

Answer 95

Listeria monocytogenes (resistant PBP) MRSA (resistant PBP) Enterococci (resistant PBP) Atypicals such as mycoplasma and chlamydia (no cell wall) Treat **listeria** with **ampicillin.** Remember, listeria causes disease in those with deficient cell-mediated immunity such as pregnant ladies, young infants, or immuocompromised patients

Answer 96

Borellia Burgdorferi: Lyme Disease Pasteurella Multocida: oral flora of cats and dogs Actinomyces Isralii: oral abscesses with dranining yellow pus Bacilus Anthracis: cutaneous anthrax. Release Edema factor and Lethal factor creating a papule that eventually is covered with black eschar. Tx: Ciprofloxacin Rickettsia Rickettsiae: Rocky Mountain Spotted Fever (erythematous macules that migrate centripetally toward the trunk)

Answer 97

- Can be used to treat MRSA (along with vancomycin and linezolid) - The mechanism is that it disrupts the bacterial membrane by creating transmembrane channels that cuase intracellular ion leakage. The resulting cellular membrane depolarization and macromolecular (DNA/RNA/protein) synthesis inhibition leads to cell death. - It also binds to and is inactivated BY pulmonary surfactant (so it is ineffective in treatment of pneumonia) Adverse: increased CK levels and increase incidence of myopathy, esp in pts taking statins

Answer 98

It can be suppressed or minimized with oral **valacyclovir** (preffered over valcyclovir as it is dosed once daily and has good bioavailability). Could use daily acyclovir or famcyclovir -These are not great at being active against latent virus forms, but can suppress multiplication as SOON as reactivation occurs. A short 7-10 day course of oral acyclovir doesn't do anything for recurrence rates, it only helps with the lesional healing time and local pain.

Answer 99

**Aspiration Pneumonia**: lung parenchyma **INFECTION**. Aspiration of upper airway or stomach **MICROBES** (anaerobes). Presents **DAYS** after aspiration event. see **FEVER**, cough, increase sputum. **CXR infiltrate** in dependent lung segment (classically **RLL**). Can progress to abscess. ABX: **Clindamycin** or B-lactam and B-lactamase inhibitor **Aspiration Pneumonitis**: Lung parenchyma **INFLAMMATION**. Aspiration of **GASTRIC ACID** with direct tissue injury. Presents **HOURS** after aspiration event. Range from **no sx**, to nonproductive cough, decreased O2. CXR: infiltrates resolve **WITHOUT abx**. Tx: supportive

Answer 100

- Gingivostomatitis is the first sign and due to its painful nature, the pt opts NOT to drink fluid and often presents to the ER with dehydration - Peak age for primary infection is 6months to 5 years

Answer 101

**Cats**: **Pasteurella** (most common) has characteristic mouse-like odor, **Bartonella** (lymphangitis in immunocompromised pts **Dogs: Pasteurella, Streptococci, S. Aureus** **Human: Anaerobes, Streptococci, Eikenella corrodens (clenched fist injury "fight bite")**

Answer 102

-Acts as a **superantigen** that activates a large number of helper T cells This results in release of **IL-2** from T cells and **IL-1** and **TNF** from macrophages This immune cascade is what is responsible for TSST sx

Answer 103

Coxiella Burnetti: usually through inhalation of air that has been contaminated by animal waste Acute: nonspecific febrile illness (HA that are retroorbital, pneumonia, thrombocytopenia) Chronic: Can be fatal if not treated

Answer 104

This low oxygen level would stimulate the kidney to produce more EPO, which would result in a compensatory erythrocytosis to maintain normal oxygen delivery

Answer 105

CD4: helper T-cell marker CD8: cytotoxic T cell CD15: cell surface marker present on granulocytes. It is also present in nearly all Reed Sternberg cells and is therefore useful in the diagnosis of Hodgkins Lymphoma CD16: low affinity Fc receptor found on the surfaces of NK cells, macrophages, and neutrophils CD19/CD20/CD21: found on B-cells (both immature and mature)...would see low in X-linked Agammaglobulinemia

Answer 106

- Overgrowth of desquamated keratin debris within the middle ear space. May erode ossicles, mastoid air cells and lead to CONDUCTIVE HEARING LOSS - Forms a round, pearly mass behind the tympanic membrane - Can be primary or secondary to trauma, infection, surgery. - Painless - Can cause small perforation in the tympanic membrane

Answer 107

- There is increased levels of ammonia and other toxins circulating around in the body due to an inability to metabolize by the liver. - With excess amonia, this is taken up by astrocytes, increasing glutamine production. This leads to increased osmolarity inside of the astrocytes causing swelling and impaired glutamine release - Hyperammonemia decreases the amount of glutamine available for conversion of glutamate in neurons resulting in decreased excitation

Answer 108

Serum is mixed with a solution of cardiolipin, lecithin, and cholesterol. If aggregation or "floccation" is seen this is indicative of antibodies against cardiolipin -This is a non-treponomal specific test, instead it is detecting antobodies to human lipids that are released as a result of cellular destruction by Treponema Pallidum (is positive in yaws, pina, bejel)

Answer 109

- Normal left ventricular ejection fraction (\>50%) - Normal end diastolic volume - Increased LV filling pressure

Answer 110

-Thickened bronchial walls with neutrophil infiltration and mucus gland enlargement (increased number of goblet cells) and patchy squamous metaplasia that is brought on by longterm smoking

Answer 111

- Common in advanced heart failure pts - this is a cyclical pattern that has periods of apnea followed by gradually increasing and decreasing tidal volumes that is followed by another apneic period - It is also seen in stoke, brain tumors, and TBI's and is often a poor prognostic sign

Answer 112

Biot-periods of apnea and hyperpnea (only pathological)

Answer 113

- small cavities that lie on either side of the laryngeal orrifice. During swallowing, **food is directed by the eppiglottis to the piroform recess** and into the esophagus - A thin layer of mucosa protects the **internal laryngeal nerve** that is a **branch of the Superior Laryngeal Nerve (CNX).** This contains only sensory and autonomic fibers (**NO MOTOR,** unlike recurrent laryngeal and external laryngeal) - This mediates the afferent limb of the **COUGH REFLEX**

Answer 114

**_Gag_** afferent --\> Glossopharyngeal Nerve efferent --\> Vagus nerve **_Cough_** afferent --\> internal laryngeal nerve (branch of superior laryngeal nerve, branch off vagus) efferent --\> vagus

Answer 115

**Nystatin** a polyene antifungal with a mechanism similar to amphotericin B. Binds to ergosterol molecules in the fungal membrane causing pores and leakage of fungal cell contents. It is NOT absorbed orally, so is given as an oral **"swish and swallow"** ## Footnote **could also use fluconazole, or caspofungin**

Answer 116

-Neutrophil Myeloperoxidase a blue-green heme based enzyme that forms hypochlorus acid (bleach)

Answer 117

Missing NADPH oxidase so more prone to catalase + organisms C: **Candida** A: **S. Aureus** T:---- A: **Pseudamonas Aeruginosum** L: **Listeria** A: **Aspergillus** S: **Serratia** E: **E. Coli** **(and Nocardia)**

Answer 118

-It will be normal because the problem is noncardiogenic pulmonary edema If the cap pressure was elevated, it is more suggestive of cardiogenic pulmonary edema In ARDS you WOULD see: - increased capillary permeability - decreased lung compliance - increased work of breathing - oxygen diffusion capacity to decrease - V/Q mismatch

Answer 119

HIV infection that was passed mom--\>infant -Could have been avoided with Zidovudine (ZDV) a nucleotide reverse transcriptase inhibitor (enzyme inhibitor) given to the infant for several weeks. The mom should have had a standard HAART administration of 2 nucleotide/nucleoside reverse transcriptase inhibitors and one third drug (protease inhibitor, NNRTI, integrase inhibitor)

Answer 120

**adenosine receptor antagonist** and **phosphodiesterase** **inhibitor** that is used as an alternate therapy for Asthma and COPD. It causes bronchodilation by increasing cAMP levels -It is metabolized by hepatic cytochrome oxidases, which can be inhibited by medications such as: **-Ciprofloxacin, Cimetidine, Macrolides, Verapamil** Toxicity presents as CNS stimulation such as seizures, tremors, insomnia as well as cardiac abnormalities (arrhythmias)

Answer 121

TB: caseating granulomas Sarcoidosis: NON-caseating granulomas

Answer 122

produced primarily by helper T-cells and is a major growth factor for T-lymphocytes IL-2 also stimulates the growth differentiation and survival of CD4 and CD8 T cells. **\*\*Stimulate the growth of helper, cytotoxic and regulatory T cells and NK cells** IL-2 as a drug is called **Aldesleukin** and is used for metastatic melanoma and renal cell carcinoma

Answer 123

Happens when tumors are treated with chemotherapy. The lysis of tumors causes release of K, Phosphorus, Uric acid to be released into the serum At physiologic pH, the uric acid is soluble, but in the acidic environment of the collecting tubule, they ppt into uric acid stones This can be prevented by treatment with Allopurinol (Inhibit xanthine oxidase) to prevent tumor lysis syndrome

Answer 124

Hyperaldosteronism can be divided into primary and secondary **Primary (Conn):** There will be hypokalemia, hypernatremia, high aldosterone, LOW renin due to feedback inhibition of renin secretion **Secondary:** overproduction of aldosterone is SECONDARY to excess renin production (renal artery stenosis, diuretic use, malignant hypertension, renin-secreting tumor Nonaldosterone causes: CAH, deoxycortisone producing adrenal tumor, Cushing syndrome, exogenous mineralcorticoids. Would present with LOW aldo, LOW renin

Answer 125

**-Spastic bladder:** urinary frequency and urge incontinence due to the presence of an upper motor neuron lesion (is common in pts developing acute lesions in the spinal cord) -The bladder **does not destend/relax properly** due to loss on inhibitory control from UMN

Answer 126

**Hypercalcemia** due to **osteolysis** induced by tumor cells, which release osteoclast-activating factor. This elevated serum Ca leads to **decreased PTH** production. The low levels of PTH lead to increased loss of Ca in urine (**hypercalciuria**) The hypercalcemia and light chain cast nephropathy cause **progressive renal failure**. This leads to loss of 1-alpha hydroxylase resulting in **low 1-25 Vit D.**

Answer 127

-hypocalcemia and hypomagnesemia due to it being a pyrophosphate analog. It can chelate calcium May lead to a reduction in PTH release, which would contribute to the hypocalcemia Both hypocalcemia and hypomagnesemia can contribute to seizures!

Answer 128

Used in acute angle glaucoma. Carbonic anhydrase modulates HCO3 formation in aqueous humor, so inhibition of CA will decrease aqueous humor production

Answer 129

Must be **central diabetes insipidus** (because nephrogenic does not respond at all and central the problem is you just are not producting ADH) Keep in mind that V2 acts on the kidney to **increase aquaporin channels to bring water back** in. **UREA** is also brought back in in the collecting duct in response to V2 in the inner medullary collecting duct, which **increases the osmotic gradient in the medulla**, which allows for the production of MAXIMALLY concentrated urine

Answer 130

The epithelium of the proximal renal tubules It looks like polygonal clear cells filled with accumulated lipids and carbohydrates, often golden-yellow due to high lipid content (on macroscopic view) Risk factors are smoking and obesity Manifests clinically as hematuria, flank pain, palpable mass (triad that is not always presenting as triad) Associated with paraneoplastic syndromes (ACTH, EPO, PTHrp, renin) Tx: Aldesleukin (IL-2)

Answer 131

**B-agonist predominantly B1\>B2** that is a **simpathomimetic** used in heart failure used in management of refractory heart failure associated with LV dysfunction and cardiogenic shock +inotrope weakly + chronotrope (**this increases HR and thus increases myocardial O2 consumption**). Although this can trigger or exacerbate myocardial ischemia, it is weighed against the benefit of end organ perfusion and improvement of cardiac output vs the drawback of cardiogenic shock

Answer 132

abnormal spasm or deminished relaxation of crycopharyngeal muscles during swallowing is thought to be the mechanism behind Zenker Diverticulum - Results in an early oropharyngeal dysphagia that presents as a feeling of food obstruction in the neck area - Pts develop halitosis/regurgitation - Pulmonary aspiration is common as well leading to pneumonia NOT A TRUE DIVERTICULUM (not all layers)

Answer 133

**O**lanzapine=**O**besity This is a second generation antipsychotic. Commonly used first line since it does not have any of the extra-pyramidal side effects that first gen antipsychotics (haloperidol) have. Olanzapine and Clozapine both have the highest metabolic side effects and it is wise to check fasting glucose and lipid pannel several months down the road when pts are on these drugs **Clozapine** can also have **agranulocytosis (requires weekly WBC monitoring) Must watch CLOZAPINE CLOZELY**

Answer 134

-It is lowest at the **functional residual capacity** (right at the bottom level of the tidal volume) **-Increased lung volumes increase PVR** due to longitudinal stretching of the alveolar capillaries by stretching the alveoli **-Decreaed lung volumes increase PVR** due to decreased radial traction from adjacent tissues on the large extra-alveolar vessels.

Answer 135

**Type 1** (immediate, IgE): **anaphalysis, allergies** **Type 2** (cytotoxic, IgG and IgM autoantibodies): **Autoimmune Hemolytic Anemia, Goodpastures** **Type 3** (immune complex, antigen-antibody complex) with complement activation: **PSGN, Lupus, Serum Sickness** **Type 4** (delayed type, T-cells and macrophages): **Contact Dermatitis, TB skin test**

Answer 136

Axillary, originates from posterior cord and carries fibers from C5 and C6

Answer 137

FF=GFR/RPF =20% is normal RPF=RBF (1-hct)

Answer 138

- Seizure pts - Anorexia pts

Answer 139

Risk of aortic stenosis at age 50!!! due to calcifications and premature atherosclerosis. This is 10-15 years before the normal tricuspid aortic valve starts to see it from normal senile calcific stenosis

Answer 140

-Would eliminate the **sensory portion of the corneal reflex** that is a branch of the Trigeminal Nerve (the nasociliary branch of the first division of the trigeminal nerve). This enters skull at superior orbital fissure **-Eye adduction** via **medial recuts muscle** that is innervated by the occulomotor nerve **(CN3)** that enters via superior orbital fissure as well

Answer 141

widespread muscular pain with associated fatigue. - effects women 20-55 most commonly - Unknown etiology but likely involves abnormal central processing of painful stimuli Can be exacerbated by excercise although can be aleviated by incremental aerobic exercise. Can be treated with TCA, SNRI

Answer 142

1. **Margination**: **increased vascular leakage** improves contact of neutrophils with endothelial lining 2. **Rolling**: roll on endothelium via lose binding of **Siacyl Lewis X to E-selectin, P-selectin on macrophages, L-selectin on neutrophils** 3. **Activation**: slow rolling allows neutrophils to sample the chemokines associated with the inflammed tissue 4. **Tight adhesion**: **CD18 to ICAM1** 5. **Transmigration**: via integrin attachment and adherence to **PCAM-1.** This protein is found at the peripheral intercellular junction of endothelial cells

Answer 143

- used to lower triglycerides - Activate PAR-alpha which leads to decreased hepatic VLDL production and increased LPL activity. This decreases triglycerides by 25-50% and increases HDL by 5-20% - Fish oil also decrease VLDL production and inhibit synthesis of Apolipoprotein B

Answer 144

-23 valent polysaccharide vaccine (Pneumovax) protects against a wider range of serotypes but antibody levels decrease over 5 years. ## Footnote **decreased incidence of replacement strains due to lack of mucosal immunity**

Answer 145

-13 valent (Prevnar) contains a nontoxic diptheria protein conjugated to the polysaccharide that boosts the immune system through T-cell recruitment Increased efficacy in the elderly and the young \< 2 -Increased mucosal immunity reduces colonization (herd protection) **-Increased immunogenic memory (strongly immunogenic)**

Answer 146

A/B. Site for attachment of **antigen** in FAB. This is the hypervariable region C. The two **disulfide** bonds that hold the heavy chains together D. C1 must bind FC portions of IgM and IgG in order to activate the classical **complement** pathway. E. The Fc binding part of the constant region of the heavy chain. This is the site for attachment to phagocytitic cells. **MACROPHAGES. MAST cells** can bind the FC portion of IgE

Answer 147

Hepatitis without jaundice (without sclera icterus =icteric) In children \<6 with HAV, 80% will be anicteric In adults, clinical disease is more severe with 70% of symptomatic patients presenting with jaundice HAV is a self limiting virus that is NOT associated with a carrier state

Answer 148

CD16, CD56 DO NOT express CD4, CD8, CD3 DO NOT require thymus for maturation DO NOT have antigen specific properties, thus DO NOT require exposure to antigen for activation thus DO NOT possess antigen memory ability ...activated by IL-12, INFY

Answer 149

Pus consists of a thin protein rich fluid and dead leukocytes, predominently neutrophils During infection, macrophages and endothelial cells release cytokines such as **IL-8** that trigger neutrophils to enter the site of infection via chemostaxis "**Clean up on aisle 8" Neutrophils recruited by IL-8 to clear infections**

Answer 150

mediates allergic reaction in local tissue Bind the Fc portion of IgE molecules IgE crosslinks upon antigen binding --\> degranulation --\> release of HISTAMINE, HEPARIN, TRYPTASE (can be used as a marker of mast cell activation) -Chromolyn sodium prevents mast cell deganulation

Answer 151

The high affinity IgE receptor is found on the surface of mast cells. The IgE receptor binds the FC of the IgE molecule. When the antigen binds to the FAB region of the IgE, multiple IgE antibodies become crosslinked resulting in aggregation of receptors on the mast cell surface This results in activation of non-receptor tyrosine kinases that triggers an intracellular cascade that results in mast cell and basophil degranulation

Answer 152

Produced by Neisseria Gonorrhea, Neisseria Meningitidis, Strep Pneumo, H. Infleunza This protease cleaves IgA at the hinge region yielding FAB and compromised Fc fragments, thus decreasing its effectiveness This facilitates bacterial adhearance to mucosal surfaces

Answer 153

Bruton Agammaglobulinemia **NO B cell maturation in bone marrow. Get buildup of pre-B Cells in bone marrow** Caused by **mutation in Bruton Tyrosine Kinase gene** -B lymphocytes normally in the cortex of lymph nodes to form lymphoid follicles Primary: dense and dormant Secondary: pale and contain proliferating B-cells **A pt with Bruton would LACK GERMINAL CENTERS where B-cells normally hang out**

Answer 154

Tetanus toxoid vaccination (formaldehyde inactivated tetanus toxin). The vaccination **initiates humoral immunity specific to the tetanus TOXIN**. -The tetanus immune globulin can be administered during the acute treatment of tetanus or for tetanus prophylaxis after an injury **\*\*Remember, tetanus disease is caused by the TOXIN, not the circulating Clostridium Tetani, thus regular host defense mechanisms are NOT effective against tetanus. REASON WHY YOU NEED TO BE VACCINATED**

Answer 155

1/ARR (absolute risk reduction) where ARR is the difference of the treatment vs the placebo group.

Answer 156

**-Vancomycin (ORAL)** - **Metronidazole** - **Fidaxomicin**: a macrolide antibiotic that that inhibits the sigma subunit of RNA polymerase leading to protein synthesis impairment (this is bacteriocidal). Particularily useful for recurrent C. Diff. It has a lower recurrence rate and higher cure rate

Answer 157

-Piriformis muscle: involved in external hip rotation

Answer 158

Vinca alkaloids: **M phase** Bleomycin: **G2 phase** Doxirubicin: **G2 phase** Antimetabolites: **S Phase** Cysplatin, Alkalating Agents: **G0, cell cycle independent**

Answer 159

**Dilusion Disorder:** \>1 dilusion \>1 month, other psychotic symptoms NOT present (NO hallucinations, NO disorganization). Typically have a persistent overridding delusion with a specific theme (genuinely believe you are married to a celebrity, genuinely believe being cheated, spied on)...must be somewhat realistic) **Schizophrenia**: periods of psychosis and disturbed behavior and thought lasting \>6 months. Need \>=2 of the following: dillusions, hallucinations, disorganized speech, disorganized or catatonic behavior, negative sx (flat affect, anhedonia)

Answer 160

Bacteremia, septic shock --\> lipopolysaccharide Neonatal meningitis --\> K1 capsular polysaccharide Gastroenteritis (bloody) --\> Shiga-like toxin Gastroenteritis (watery) --\> Heat labile (cAMP), heat stable (cGMP)enterotoxins UTI --\> P fibriae

Answer 161

mild withdrawal --\> seizures --\> hallucinations --\> DT

Answer 162

Daytime: Modafinil, Amphetamines Nighttime: Sodium oxybate

Answer 163

These pts are started on ACE-I because the diabetic neuropathy stems from the nonenzyamatic glycosylation of the GBM that is favoring the efferent \>afferent arteriole. This leads to increased GFR and eventual microalbuminURIA. This can be delayed with an ACE-I - When starting ACE-I, it is common to see first dose hypotension (espectially when the pt is already on a diuretic and has high renin levels). The ACE-I causes an abrupt removal of the vasoconstrictive effects of ANG II resulting in decreased peripheral vascular resistance and a precipitous drop in BP - This can be avoided by giving small doses and incrementally increasing

Answer 164

THERE IS NO EFFECT!! PaO2 is the amount of O2 DISSOLVED in plasma and represents the partial pressure of oxygen. What is decreased is the amount of hemoglobin that are bound to O2. This will decrease as CO has a higher affinity for Hb

Answer 165

Vancomycin --\> inhibit gram + bacteria Polymyxin --\> inhibit gram - bacteria Nystatin --\> inhibit yeast Trimethoprim --\> inhibit proteus Used to isolate..**..Neiseria**

Answer 166

Neurobehavioral problems LONG face Prominent forehead Large Ears Prominent chin

Answer 167

-Binds ergosterol (unique to fungi); forms membrane pores that allow leakage of electrolytes "Ampho**TER**icin **TEARS** holes in fungal membrane" Use for serious systemic mycoses: **-Cryptoccus** **Coccidiode** **-Histoplasmosa** **-Candida** **-Mucor** Supplement K and Mg because of altered renal tubule permeability -Side efects: F/C. hypotension, nephrotoxicity, arrhythmias, anemia, IV phlebitis \*Hydration decreases nephrotoxicity.

Answer 168

Mississippi and Ohio River Valley --\> **Histoplasmosis** Eastern US and Central America (great lakes)--\> **Blastomycosis** Southwestern US, California--\> **Coccidioidomycosis** Latin America--\> **Paracoccidioidomycosis**

Answer 169

Histoplasmosis --\> smaller than RBC (macrophage filled with histo) Blastomycosis --\> same size as RBC (broad-based budding) Coccidiodomycosis --\> much larger than RBC (Spheru;e filled with endospores) Paracoccidioidomycosis --\>MUCH larger than RBC (Captain Wheel)

Answer 170

- Villous Atrophy - Crypt Hyperplasia - Intraepithelial lymphocyte infiltration Dx: anti-tissue trans-glutaminase (anti-TTG), IgA anti-endomysial and is confirmed by tissue biopsy Tx: with a gluten free diet

Answer 171

RPF= PAH clearance (remember this is fully secreted in PCT, not reabsorbed at all, but is also not filtered at all at the glomerulus, so is a perfect number to use for RPF!!!!) RPF=PAH clearance =[(urine PAH x urine flow)/(plasma PAH)] Then remember that RBF=(PAH clearance)/(1-Hct)

Answer 172

RNA Polymerase 1 functions exclusively within the nucleolus (the site of ribosomal maturation and assembly) to transcribe the 45s pre-RNA gene, which codes for MOST of the RNA components

Answer 173

Occurs with simultaneous infection of a cell with 2 viruses and results in progeny virus that has nucleocapsid components of A and B \*The key here is that there is no exchange of genomic viral genomes and thus in the subsequent generations, A --\> A and B --\> B

Answer 174

Use visual aids to aid in explaination DO NOT make the pt read something, may be embarassing and unnecessary

Answer 175

Fertilizaiton by two sperm of two eggs and ALWAYS have 2 amnions and 2 chorions

Answer 176

A/B. Phosphoglucomutase (interconverts Glucose-1-phosphate and Glucose-6-phosphate C. Glucose-6-phosphate dehydrogenase (G6PD) D. Glucose-6-phosphatase (McArdle) E. Hexokinase/Glucokinase (hemolytic anemia, rare) F/G Phosphoglucose Isomerase (hemolytic anemia)

Answer 177

**Ionotropic**: ion channels that open directly upon ligand binding. NICOTINIC...allow immediate influx of ions, such as a nonselective cation channels that open after the binding of ACh. **Metabotropic**: use second messengers. MUSCARINIC

Answer 178

**Patent ductus arteriosus**, an embryonic development of the **6th aortic arch** that allows blood to pass from the pulmonary artery to the descending aorta and bypass the lungs and left side of the heart. - The vessel closes with the decrease of prostaglandin E2 and increased oxygen concentration. - If patent after birth, results in a L --\> R shunt that can cause left ventricular volume overload and symptoms of heart failure - Can close pharmalogically by **indomethacin** (PGE2 inhibitor)

Answer 179

IV benzodiazepam (lorazepam, diazepam) Benzos enhance GABA-A causing influx of negatively charged Cl ions in response to GABA binding. This leads to hyperpolarization of the post-synaptic neuron and suppression of AP firing (anticonvulsant effect) Status epilepticus is reccurent seizure or seuzire lasting \>5min

Answer 180

**OCP** **Multiparidy** **Breastfeeding** **Salpingo--oophrectomy** -Cancer antigen-125 is a protein produced by ovarian epithelium and is usually increased in cancerous ovarian cells compared to normal cells (not sensitive or specific)

Answer 181

Increased ICP with no apparent cause - Young woman of childbearing age w/ daily headache. bilateral symmetrical papilledema, transient vision change, and sx worsen when bending down - Compression of optic nerve externally that impairs axoplasmic flow within optic nerve tx: weight loss, acetazolamide, topiramate (seizure)

Answer 182

- Potentiates GABAa - A highly lipophilic drug that is used for both induction and maintainence of general anesthesia as well as procedural sedation - Onset of action is 30 sec, and duration is \<10 min. It goes where blood flow is highest (brain) first then goes to areas where blood flow is lower such as fat, muscle tissue

Answer 183

Can cause recurrent lobar hemorrhage is a consequence of B-amyloid deposition in the walls of small--\> medium sized cerebral arteries resulting in vessel wall leakage and predisposition to rupture \*The most common cause of spontaneous lobar hemorrhage in adults \>60 and tends to involve the parietal and occipital lobes

Answer 184

Early diastolic murmur - Signs and symptoms of left heart failure are common - more advanced cases are a more holosystolic murmur while earlier cases are associated with an early diastolic murmur - MOST commonly caused by aortic root dilation or bicuspid aortic valve

Answer 185

- usually results in intraventricular hemorrhage (most common in infants born before 32 weeks gestation and \<1500 grams), and almost always occurs in first 5 days postnatal - The germinal matrix is a highly vascular area where neurons and glial cells migrate out of during development. There are many thin walled vessels in this area that lack the glial fibers and support that other vessels have in the brain

Answer 186

A=Aspart (first)

Answer 187

-Lactic acidosis is produced by over production or underexcretion of lactic acid. End organ hypoperfusion in septic shock impairs tissue oxygenation and decreases oxidative phosphorylation leading to a buildup of NADH and shunting of pyruvate to lactate following glycolysis

Answer 188

-EPINEPHRINE!! This is the drug of choice due to its ability to reverse all of the pathophysiologic mechanisms of anaphylaxis. 1. Stimulation of Alpha-1 counteracts the vasodilation of cutaneous and viscera vasculature. 2. Stim B1 to increase contractility and CO to increase BP and improve peripheral circulation 3. Stim B2 to result in bronchodilation Diphenhydramine may be used AFTER stabilization of the pt, but is NOT a first line med!

Answer 189

- This is the spot where the frontal, parietal, temporal and sphenoid bone all join. - A fracture here is common to cause a middle meningial artery laceration. The middle meningial artery is a branch off the maxillary artery -This rupture of an ARTERY --\> epidural hematoma, which can lead to increased ICP and cushing reflex, brain herniation, and death

Answer 190

Pts born with **agenesis of the sacrum, and lumbar spine area** and experience flaccid paralysis of the legs, and urinary incontinence -It is frequently related to **maternal diabetes** that were poorly controlled though there are other factors likely at play

Answer 191

-ribonucleoprotein that **adds TTAGGG repeats** to 3' end of chromosome (telomere region) It synthesizes single stranded DNA using single stranded RNA as a template (**RNA dependent DNA Polymerase**) Stem cells have very long telomeres due to their high telomerase activity Myocardial cells, neurons, pancreatic beta cells would be examples of cells that have SHORT telomeres as they fully differentiated cells

Answer 192

Caused by E. Coli O157:H7 or Shigella Dystentarie The **Shiga toxin enters the circulation** and causes capillary endothelial damage, resulting in **platelet activation and microthrombi**. This results in **thrombocytopenia** due to the platelet consumption and **schistocytes** from the RBCs damaged during the microthrombi resulting in **hemolytic anemia** The hemolytic anemia causes **decreaed hemoglobin and haptoglobin** in the blood as well as **increased serum lactate and unconjugated billurubin**

Answer 193

Class 1C antiarrhythmic that is typically used to treat SVT caused by AFIB These bind to the Na channels responsible for phase 0 depolarization and prolong QRS duration Class 1C drugs are the slowest to dissociate from the Na channels resulting in a "use dependence" in which their sodium blocking effect is increased when the HR is increased

Answer 194

- A **class III antiarrhythmic** that blocks outward potassium current during repolarization. As a result, it **increases the QT but NOT the QRS** - This expresses **reverse use dependence,** the lower the HR, the more effect it has

Answer 195

-The macula is a dense bit of cones located 1.5 mm near the retina **Macular lesions impair central vision and result in CENTRAL SCOTOMA** Scotoma = a visual defect surrounded by regular vision

Answer 196

ATM gene responsible for DNA break repair --\> cell cycle arrest -Mutation in this gene is AR and results in cerebellar ataxia, telangectasias and increased risk of sinopulmonary infections Usually have an IgA deficiency as well Can see an increased AFP in these pts too

Answer 197

Begins with the **transcription of collagen in the nucleus**. **Alpha chains** are then synthesized by the **RER** bound ribosomes and directed into the cisternae of the RER. Within the RER, **proline and Lysine are post-translationally hydroxylated** to hydroxylysine and hydroxyproline via prolyl hydroxylase and lysyl hydroxylase. Defective hydroxylation severely diminishes the amount of collagen secreted by fibroblasts and impairs triple helix production. **VITAMIN C is required for HYDROXYLATION**

Answer 198

Parvovirus **B19 is a single stranded DNA naked virus** that is also called **5th disease** (think getting 5 fingers across face) - Causes classic **slapped cheek** look on kids that develops after the nonspecific prodrome sx resolve (fever, malaise, congestion, HA). The rash may be a result of immune complex deposition (IgM, IgG) - Parvovirus **replicates in ERYTHROCYTE PRECURSORS of bone marrow**. Can see aplastic crisis in pts with sickle cell disease

Answer 199

**Rubeola**: Prodrome symptoms of: **Cough, Coryza, Conjunctivitis, fever, and Koplik Spots** on the buccal mucosa (these are pathognomonic for Measles These symptoms precede a **maculopapular exanthem** that starts on the face and spreads downward

Answer 200

life threatening reaction to anti-psychotic medications, which block dopamine receptors in the brain Presents clinically with diffuse muscle rigidity, high fever, autonomic instability (HTN, tachycardia), and altered sensorium. CK through the roof as pt has rhabdo \*\*Think LEAD PIPE RIGIDITY FOR NMS\* \*Think hyperreflexia for serotonin syndrome Tx: discontinue psych med, **DANTROLENE** (blocks release of Ca from sarcoplasmic reticulum via antagonizing ryanodine receptors)

Answer 201

Trendelenburg gate is the **dropping of the hip on the contralateral side that is affected.** On the affected side, the **superior gluteal nerve** is affected. This can be a result of a misplaced injection. The **proper site for an injection is superiorlateral quadrant at a 90 degree entrance is correct.** Injections into superiormedial --\> risk superior gluteal Injections into superiormedial, inferiormedial, inferiorlateral are ALL increased risk of --\> sciatic nerve involvement

Answer 202

**Hemolytic Anemia, Hypercoagulability, and Pancytopenia** is the triad of the disorder. The problem is acquired mutation in PIGA gene that causes absence of **GPI anchor** that attach **CD55 and CD59**. These proteins help to inactivate complement and prevent MAC from activating. Since they are not functioning, **complement is activated too much and normal cells are broken down via a complement-mediated-hemolysis** -Pts can also develop Budd-Chiarii Syndrome due to release of free hemoglobin and prothrombotic factors from lysed cells

Answer 203

Because hexokinase can take over and convert frucose --\> fructose-6-phoshate instead of the fructokinase that normally converts fructose --\> fructose-1-phosphate This is NOT like Hereditary fructose intolerance where you are deficient in Aldolase B. At this point, you have already converted to Fructose-1-phosphate and are STUCK and cannot convert back via hexokinase to Fructose-6-phosphate

Answer 204

**Neural Crest Origin** Schwannomas 100% Neurofibromas 100% Ependamomas Astrogliomas Melanomas Langerhan Cells

Answer 205

"Some Nasty Killers Have Some Capsule Protection" **Strep Pneumo** **Neisseria Meningitis** **Klebsiella** **Haemophilus Influenza** **Salmonella Typhi** **Cryptococcus Neoformans** **Pseudamonas Auerginosa** -Keep in mind these would all be difficult for an asplenic pt, IgG def, C3 def, Bruton's. Capsule is usually major virulence factor, and if + Quellung, probably one of these bugs Big mucoid colonies on blood agar is Klebsiella

Answer 206

Pernicious anemia is an autoimmune disorder caused by CD4+ cells against parietal cells in the gastric body and fundus. Over time, this results in atrophic gastritis A: simple columnar epithelium: secretes mucous B: Upper glandular layer: where parietal cells secrete gastric acid and intrinsic factor C: Deeper aspect of gastric glands: This is where Chief cells hang out and secrete pepsinogen D: Muscularis Mucosa: separates lamina propria from submucosa E: Submucosa: Where CT is

Answer 207

Leukotriene B4 IL-8 C5a Bacterial products

Answer 208

Early: APP (chr21), presenilin 1, presenilin 2 Late: apoE4

Answer 209

Tx w/ **cholinesterase inhibitor such as pyridostigmine**. Side effects are excessive cholinergic stimulation of the gut leading to abd cramping, sweating, diarrhea, nausea. These symptoms can be treated with **Scopolamine**, a selective muscarinic ACh antagonist that reduces the effect of cholinesterase inhibitors (also used in **motion sickness**, which presents with very similar sx)

Answer 210

Hyperventilate to bring down the pCO2. This causes vasoconstriction and reduction in cerebral blood flow resulting in decreased ICP \*Think that the ICP is already raised from edema, so trying to do anything to reduce this swelling\*

Answer 211

Important for several carboxylase enzymes Deficiency of biotin can arise from poor diet, excessive raw egg white consumption (due to high levels of biotin-binding avidin in egg whites) **1. Pyruvate carboxylase** **2. Acetyl CoA carboxylase** **3. Proponyl CoA carboxylase** Present with non-specific symptoms but can include dermatologic changes\* mental status change, anorexia

Answer 212

Phenytoin! due to increased expression of PDGF It occurs in 50% of pts who have been on phenytoin for 3-4 months or longer (also cyclosporine and tacrolimus --\> calcineurin inhibitor, as well as CCB)

Answer 213

A. Caudate (A/C are striatum together) B. Internal Capsule C. Insular Cortex (limbic system) D. Putamen E. Globus Pallidus (D/E make up Lentiform nucleus)

Answer 214

**Naltrexone**: blocks the mu-opioid receptor. It blocks the rewarding and reinforcing effects of alcohol and has been shown to reduce the craving of alcohol As a reminder, Disulfuram (antabuse) does inhibit aldehyde dehydrogenase and causes accumulation of acetaldehyde and causes the unpleasant hangover-like symptoms

Answer 215

**1. Diptheria Antitoxin** (inactivates all circulating toxin, but is ineffective against toxin that has already gained access to cardiac or neural cells). This process is considered **PASSIVE IMMUNIZATION**, as it represents the transfer of pre-existing, neutralizing antibodies **2. PCN or erythromycin** kills bacteria and halts making of toxin **3. DPT vaccine** **(active immunization)** protects against future infections

Answer 216

-Blocks Mu-receptor via binding to Gi proteins. On **presynaptic** side: results in **closure of voltage-gated calcium channels**, reduced calcium influx and thus decreased excitatory NT release. **On post-synaptic side**: **opens potassium channels** and allows for K efflux from cells leading to membrane **hyperpolarizaiton**

Answer 217

Lower abdominal aorta --\> Coronary Arteries --\> carotids --\> popliteal

Answer 218

Rare complication of **measles (rubeola)** that occurs years after initial infection. Presents with personality changes --\> lethargy --\> difficulty in school/odd behavior --\> dementia --\> myoclonic jerking --\> flaccidity + decorticate rigidity. Rembmer, the measles is a paramyxovirus that presents with **cough, coryza, conjunctivitis and Koplik spots that progress to maculopapular rash** that starts at the head and spreads downward

Answer 219

1. **Lithium**: **hypothyroidism**, DM, ebstein anomaly, tremor 2. **Valproate**: **HEPATOTOXICITY**, neural tube defects 3. **Carbamezapine**: **AGRANULOCYTOSIS**, hyponatremia, **NTD** 4. **Lamotrigine**: **SJS**

Answer 220

**activates trypsinogen to trypsin** Trypsin can then go ahead and activate all the other pancreatic enzymes. Trypsin can also begin to break down proteins to oligopeptides and amino acids Enteropeptidase hangs out in the brush border of the duodenum

Answer 221

Can be shorcutted by thymidine supplementation. This converts dUMP to dTMP

Answer 222

R testicular vein: **inferior vena cava** L testicular artery: **abdominal aorta** R testicular artery: **abdominal aorta** L testicular vein: **L** **_RENAL VEIN_** reason why there is increased risk of varicocele on the left side

Answer 223

seen in **small cell lung cancer,** breast, ovarian, and uterine cancer **Anti-YO, anti P/Q and anti-HU antibodies** pts present with worsening dizziness, atazia, and visual disturbances These **cross react with Purkinje neuron antigens** leading to acute onset degeneration of the cerebellum

Answer 224

\*the posteriormedial papillary muscle is supplied solely by the posterior descending artery unlike the anteriormedial papillary muscle that is supplied by a duel blood supply of the LAD and the L circumflex papillary muscle rupture is a life-threatening condition that happens 3-5 days after a myocardial infarction and presents with acute mitral regurgitation and pulmonary edema

Answer 225

IF shows granular "lumpy bumpy" (not linear like seen on goodpastures syndrome) What is actually showing up is C3b, IgG, and IgM in the mesangium and basement membranes

Answer 226

monocyte/macrophage lineage

Answer 227

scleroderma has high pressure at prox esophagus achalsia is high LES tone

Answer 228

**Scrotum --\> superficial inguinal lymph nodes**. These lymph nodes drain nearly **all cutaneous lymph from the umbilicus to the feet** including the external genitalia and anus (up to the dentate line) THE EXCEPTION is the testes, glans penis, and cutaneous portion of posterior calf **Lymph from the testes --\> para-aortic** (retroperitoneal) **Glans penis and posterior calf --\> deep inguinal lymph nodes**

Answer 229

The picture is of Dermatomyositis, an autoimmune disease characterized by proximal muscle weakness resembling poliomyolitis. findings include heliotrope rash, Gottron pappules (pictured on hands) -This condition may occur alone or as part of a paraneoplastic syndrome from ovarian adenocarcinoma (but can also be lung, colorecta, non-hodgkins) Anti-jo, Anti-SRP, anti-Mi-2

Answer 230

Used as treatment for hyperlipidemia to inhibit hormone sensitive lipase and reduce hepatic VLDL synthesis Side effect include **flushing, warmth and itching** This is mediated by **PROSTAGLANDINS** (PGD2 and PGE2) **ASA** can **decrease** this side effect if given 30 min prior to administration of niacin

Answer 231

Arsenic poisoning. Binds to **sulfhydryl groups**, impairing cellular respiration via **inhibiton of pyruvate dehydrogenase** and disruption of gluconeogenesis GARLIC odor is often found on pt breath. Abd pain, diarrhea (watery), delerium, and hypotension are also seen. Tx: dimercaprol (chelating agent)

Answer 232

AD inheritence of congenital telangectasias to the skin ALSO called hereditary hemorrhagic telangectasia presents with recurrent nose bleeds, skin discolorations

Answer 233

used in asthma. A phosphodiesterase inhibitor that likely causes bronchodilation by increasing cAMP Side effects: (think about it having the same mechaism as caffeine) at low to moderate doses, can cause mild cortical arousal and insomina. Acute intox can cause nausea/vomiting, diarrhea, cardiac arrhythmias and seizures. Seizures are the major cause of morbidity

Answer 234

Reliability (precision) measure of statistical variation. A reliable test is reproducible but not necessarily giving the right answer (bottom two on figure) Validity (accuracy) the tests ability to measure what it is supposed to measure

Answer 235

\> 2 weeks and need \>5 of the 9 possible symptoms, with no hx of mania or hypomania and no curent substance abuse that could be causing problem

Answer 236

reaction associated with CYP450 system some pro-carcinogens are metabolized by cytochrome P450 microsomal monoxygenase

Answer 237

distinct foci found within eukaryotic cells that are involved in mRNA regulation and turnover within the CYTOPLASM

Answer 238

Great saphenous vein is taken just inferiorlateral to the pubic tubercle (keep in mind the left internal mammary (thoracic) vein is preferred over the saphenous but often times is already used or not available) Right near the femoral triangle

Answer 239

Roux-en-Y Gastric Bypass Can result in Small Intestinal Bacterial Overgrowth (SIBO) Enteric bacteria produce Vitamin K and folate, which inhibit proliferation of surrounding pathogenic bacteria and digest unabsorbed dietary sugars **See deficiency in A,D,E,B12,Iron but increase in vit K, folate**

Answer 240

DVT, central vein thrombosis, Cerebral vein thrombosis and recurrent pregnency loss -Remember that Factor V Leiden produces a mutant factor V that is resistent to inhibition by protein C. This is the most common cause of hypercoagulability in caucasions

Answer 241

1. Dorsal column of the spinal cord 2. Lateral corticospinal tracts 3. Axonal degeneration of peripheral nerves Called subacute combined degeneration. This is due to abnormal myelin synthesis

Answer 242

Involvement of the suspensory ligaments of the breast (also called Cooper Ligaments)

Answer 243

COMPT inhibitor that increases bioavailability of levodopa by inhibiting its peripheral methylation. If you combine levodopa and Entacapone, you can prolong its duration in the periphery remember levodopa is the precursor of Dopamine and can cross the BBB

Answer 244

Shigella cannot bind all intestinal cells. Instead, shigella can **bind microfold (M) cells at the base of the mucosal villi within a Peyers Patch** region of the ileal mucosa. Shigella **endocytoses through the M cell and lyses the endosome**, multiplies and then spreads laterally inside other epithelial cells **Infectious dose is VERY LOW** and it is resisant to gastric acids Causes bloody diarrhea

Answer 245

The most common cause is from an atherosclerotic plaque in the internal carotid. This then travels to the opthalmic artery and then to the retinal artery. Common cause of acute, painless, monocular vision loss

Answer 246

follicular lymphoma overexpression of BCL2 (chr 18) to IgG heavy chain (chr14) BCL2 keeps Cytochrome C from exiting the nucleus and therefore makes the cell immortal by evading apoptosis

Answer 247

**Trinucleotide repeat of CAG** on huntington gene that encodes for huntingtin protein. Expansion of the polyglutamine region results in a **gain of function mutation.** **Autosomal Dominant** **Transcriptional repression** is one of the mechanisms by which the huntingin protein cuases disease. See **_increased histone deacetylation, silencing the genes necessary for neuronal survival_**

Answer 248

**ACE/ARB** result in **low Angiotensin II** that results in **fetal renal maldevelopment** which leads to decreased diuresis and **OLIGOHYDRAMNIOS** If oligohydramnios is severe, can result in pulmonary hypoplasia and skeletal defects **(POTTER SEQUENCE)** **Low ANG II can also result in hypocalvaria (hypoplasia of skull bones)**

Answer 249

Pt has Pellagra...a deficiency of niacin (B3) **Pellagra: Diarrhea, Dementia, Dermatitis (3 D's of B3)** **Niacin** is a precursor for NAD and NADP, two important cofactors for many dehydrogenase and reductase enzymes. Often found deficient in **ALCOHOLICS** Cofactor for: **1. Isocitrate dehydrogenase** **2. Malate dehydrogenase** **3. alpha-ketoglutarate dehydrogenase complex** **4. pyruvate dehydrogenase**

Answer 250

This is elevated systolic blood pressure with normal diastolic blood pressure. Called **isolated systolic hypertension** and is often seen in pts over 60 and is responsible for 60-80% of hypertension in this age group. **Increased arterial stiffness** is a common manifestation of aging including **increased aortic stiffening**

Answer 251

Vd=amount of drug given(mg) / plasma concentration of drug (mg/L) This is a hypothetical amount of fluid that the drug would need to be uniformly distributed into to produce an observed plasma concentration **1. Low --\> blood --\> large charged molecules, plasma protein bound (3-5L)** **2. medium --\> ecf --\> small hydrophilic molecules (14-16L)** **3. high --\> all tissues including fat --\> small lipophilic molecules, esp if bound to tissue protein (41L)**

Answer 252

Common in burn pts and the treatment is: **ticardillin, pipercillin, cefapime, ceftazadime, cipro, levo, carbapenems** NOT moxifloxacin, NOT doxycycline, NOT ceftriaxone, NOT TMP-SMX

Answer 253

mesoderm also muscles, CT, cartilage, CV system, lymphatic system, blood, internal genitalia, kidneys, ureters MOST gut tissue is endodermal, but the spleen is unique as it is derived from mesenchymal tissue

Answer 254

Hook of the Hamate This is an ulnar neuropathy. The nerve enters the wrist between the hook of the hamate and the pisiform bone through guyon's canal MOST often the ulnar nerve is injured at the elbow "funny bone"

Answer 255

UV exposure creates **thimadine dimers** --\> **endonuclease** complex recognizes deformed helix --\> single strang **cleavage** on both sides of damage --\> damaged DNA is **discarded** --\> DNA **polymerase** synthesizes replacement --\> DNA **ligase** seals gap

Answer 256

**Subacute granulomatous thyroiditis (de Quervain thyroiditis)** typically f**ollows a viral illness.** Pts may experience transient hyperthyroid phase that is characterized by elevated T4/T3 suppressed TSH and decreaed iodine. **Resolves within 6 months** Pathology: early neutrophilic infiltrate with microabscess formation. This is replaced with **lymphocytic infiltrate with macrophages and giant cells**

Answer 257

paraventricular and supraoptic nuclei of the hypothalamus

Answer 258

**-Bend**azoles (worms are **bend**y) (Albendazole) These are the most common helminth infection in children ages 5-10 in the usa. Dx: scotch tape test looking for eggs

Answer 259

**Diverticulosis:** is an outpouching (false diverticulum) caused by **increase pressure (pulsion)** during bowel movements. This pressure herniates through areas of focal weakness in the muscularis (false diverticula). Most commonly affects the **sigmoid colon** and can present with **painless hematochezia** **Diverticulitis:** when diverticula become inflammed causing LLQ pain, low grade fever, constipation or diarrhea

Answer 260

passively absorbed in small intestine. Blood and urine levels decrease with mucosal defect or bacterial overgrowth. it is a monosaccharide that is abosrbed directly without the action of pancreatic enzymes and can be used to test for brush border absorptive function independent of pancreatic function

Answer 261

**IL-1** **IL-6** **TNF-alpha** These three cytokines (which are **released by neutrophils**) mediate systemic inflammatory response and stimulate hepatic secretion of acute phase proteins (fibrinogen). When **fibrinogen** specifically is activated, it causes RBC to form stacks **roleaux** that **sedimate faster than normal RBC** (thus the increased ESR)

Answer 262

This patient has atopic dermatitis (eczema) that can be triggered by various environmental stimuli. Intense pruritis is the hallmark of this disorder and dx cannot be made without it. Of note, the allergic triad of Asthma, Atopic Dermatitis, and Allergic Rhinitis is very common, esp in kids with a family history

Answer 263

1. Precursors proliferate and mature in the BONE MARROW 2. Mature B-cells migrate to lymph nodes, where they are exposed to antigens (some B-cells become activated to plasma cells expressing IgM through T-cell independent process) 3. B-cells migrate to lymphoid follicles in the lymphoid cortex where they from germinal centers 4. Isotype switching then occurs in the germinal centers (this requires CD40 binding to CD40L expressed by activated T-cells

Answer 264

Both maternal and fetus (if female) virulization Females will have normal internal genitalia but male external genitalia due to exposure to testosterone (cliteromegaly)

Answer 265

**IgE independent:** opioids, radiocontrast dyes, vancomycin can induce mast cell degranulation by PKA or P13 kinase **IgE dependent:** this is more common with environmental exposures such as foods or vespid stings or with meds such as beta-lactams and sulfonamide antibiotics

Answer 266

caused by **ischemic nerve damage to CN3** that presents with acute onset diplopia. The affected eye assumes a "**down and out"** position due to unopposed pull by superior oblique and lateral rectus. The **pupil is NORMAL and REACTIVE**

Answer 267

This is a classic example of psoriasis that is made up of sharply demarcated salmon plaques covered with a losely adherent silvery scale that commonly affects the extensor surfaces. Tx: topical Vitamin D (in form of calcipotriene or calcitriol). This has been shown to inhibit T-cell proliferation. This binds and inhibits keratinocyte proliferation and stimulates keratinocyte differentiation

Answer 268

Short term: NSAIDS, Glucocorticoids Long term: Disease modifying anti-rheumatic drugs (DMARDs) Methotrexate, sulfasalazine, hydroxychloroquinine, minocycline, TNF-a inhibitors

Answer 269

Low molecular weight heparin that is used as first line treatment in a pt with a DVT This also does NOT cross the placenta and are a bridge to Warfarin tx that will be the longstanding tx of DVT

Answer 270

consistent with a defect in the fatty acid b-odixation in the mitochondria The most common defect is **medium chain acetyl-CoA dehydrogenase deficiency (MCAD)** Most pts are asymptomatic until they experience a significant fasting period

Answer 271

Most consistent with a **neural tube defect.** **See an increase in alpha-fetal protein as well as ACh** NTD occur because of failure of fusion of the neural plate during the 4th week of development AFP can cross the placenta and is detectable in the maternal serum. ACE cannot

Answer 272

Increased production 1. Tumor Lysis Syndrome 2. Myeloproliferative Disease 3. Primary gout (idiopathic) 4. Hypoxanthine Guanine phosphoribosyl transferase deficiency \_\_\_\_\_\_\_\_\_\_ Decreased clearance 5. Chronic kidney disease 6. Thiazide/Loop Diuretics

Answer 273

Subacute combined degeneration (B12 deficiency) -Can occur from pernicious anemia, gastectomy, strict vegan diet pts also develop atrophic glossitis

Answer 274

1. Catarrhal Phase: similar to many URT infections 2. Paroxysmal Phase: severe coughing spells with classic whoop 3. Convalescent phase: cough improves This should not be a problem with immunizations, but if not immunized, becoming more common. This can happen in adults as well if they decide not to be immunized or get boosters Pertussis: Gram - coccobacillus Bordatella Pertussis

Answer 275

This is a **cavernous hemangioma** and is the most common benign liver tumor that presents in adults 30-50 years old. -Cavernous blood filled vascular spaces of variable sizes lined by a single epithelial layer **BIOPSY CONTRAINDICATED because of risk of HEMORRHAGE**

Answer 276

**S3:** this is a **ventricular gallop sound heard after S2.** Heard during rapid filling of ventricles in diastole. Turbulent blood flow to the ventricles due to increased volume. Seen in **pregnancy, heart failure, restrictive cardiomyopathy** **S4**: this is a **atrial gallop sound heard before S1** heard immediately after atrial contraction as blood is forced into a STIFF ventricle. Seen in healthy older adults, ventricular hypertrophy, and acute myocardial infarction

Answer 277

**_Osteoblast:_** **Bone specific Alkaline Phosphatase** **Osteoblasts release alk phos** as they build bone Bone specific ALP can be differentiated by that released by the liver by exposing it to heat and easily denaturing it **(Boil=Bone)** **_Osteoclast_**: **tartrate-resistant alkaline phosphatase (TRAP)** (not really used because of cross-reactivity with acid phosphatase from other tissues)

Answer 278

This suggests **RENAL VEIN THROMBOSIS** due to loss of **Antithrombin III** in the urine because of the nephrotic syndrome

Answer 279

steroid and phospholipid biosynthesis

Answer 280

Total Peripheral Resistence= 1/R_total=1/R₁+1/R₂+1/R_n.... Systemic circulation is arranged in parallel

Answer 281

**1. Lipooligosaccharide (LOS)** --\> this endotoxin causes sepsis by inducing a systemic inflammatory response caused by an increase in TNF-alpha, IL-1beta, IL-6, and IL-8. Can eventually lead to Waterhouse Friderechson (hemorrhage of adrenals) **2. Polysaccharide Capsule** **3. IgA protease**

Answer 282

This pt has **prinzmetal angina** (coronary vasospasm) Can be caused by **cocaine, dyhydroergotamine (an ergot alkaloid that is used in migrane headaches because it causes alpha agonist and serotonic agonist), cigarette smoking, amphetamines, triptans**

Answer 283

a **nonabsorbable antibiotic that alters GI flora to decrease intestinal production and absorption of ammonia**. Typically **used in addition to lactulose** (traps NH4+ for excretion) to treat **hepatic encephalopathy**

Answer 284

The aortic isthmus (just past the arch of the aorta) because it is tethered by the ligamentum arteriosum and is relatively fixed and immobile compared to adjacent descending aorta

Answer 285

The med is Atropine (reversible antagonist of muscarinic ACh receptors) (anticholinergic drug) A common side effect is eye pain due to flair-up of glaucoma (due to increased intraoccular pressure)

Answer 286

**Power =1-Beta** where beta is **False negative (or a type II error)** -Increase power by: **1. increase sample size** **2. increase expected effect size** **3. increase precision of measurement**

Answer 287

**#1: 46XX** (this is one sperm that was 23X that fertilized with inactive egg and replicated itself) **#2 46 XY** (this would mean two sperm fertilized an ovum with inactive maternal chromosomes) **Women through the door first** See no fetal structures increased risk of cancer and choriocarcinoma (1-3%)

Answer 288

The lateral aspect of the midpons at the level of the middle cerebellar peduncle

Answer 289

This is a classic example of parvovirus (a nonenveloped single stranded DNA virus) that is part of the O in TORCHES. Parvovirus responsible for erythema infectiosum = 5th disease (five fingers when slapped) Can cause hydrops if exposed in early pregnancy (due to interruption of erythropoeisis leading to profoudn anemia and CHF)

Answer 290

This is **neurofibromatosis type 1 and it is Autosomal Dominant** -This is a mutation on the NF-1 gene on Chr 17 Presentation: **1. Cafe-au-lait spots** **2. Neurofibromas** **3. Lisch Nodules (hammartomas of iris)** **4. Congenital pseudoarthritis** **5. Other associated tumors (such as gliomas, astrocytomas, pheochromocytomas)**

Answer 291

Absent P-waves. Iregularly irregular R-R intervals, narrow QRS -Abberent electrical impulses that arise within regions of heightened atrial excitability. This leads to electrical remodeling of the atria with the development of shortened refractory periods and increased conductivity **\*The AV node refractory period regulates the number of atrial impulses that reach the ventricle\***

Answer 292

**Leucine, Lycine** These would need to be increased in a patient with a **pyruvate dehyrogenase deficiency** (cannot enter the TCA cycle), thus these pts need to be exclusively in Ketogenesis. This disorder causes lactic acidosis and neurologic defects

Answer 293

**Nimodipine**: a **calcium channel blocker** can be given after a SAH (that is often a result of a ruptured berry aneurysm in ADPKD) -**Vasospasm** occurs in SAH in 20-30% of pts and leads to AMS, focal neurological deficits. This most often occurs **7-8 days following a SAH**

Answer 294

Moderate amounts cause dissociative symptoms. Causes hallucinations and violent behavior with higher doses **NMDA antagonist** and secondarily it inhibits the reuptake of NE, 5HT, DA and also has effects on sigma-opioid receptors **Think PCP BAD drug = antagonist**

Answer 295

Characterized by increased sodium reabsorption from the collecting tubule. This creates a negative charge in the lumen pulling H+ and K+ into the lumen. This result in a hypernatremic, hypokalemic, metabolic alkalosis . The increased H+ in the lumen results in an increase HCO3-/Cl exchanger which promotes bicarb production The hypernatremia and pedal edema are rarely seen due to aldosterone escape. This is due to increased plama volume leading to increased renal blood flow leading to naturesis which limits the net sodium retention

Answer 296

reproducible (gives very similar results whether or not they are accurate) =precise

Answer 297

provides osmotic load to draw water into the lumen to treat constipation Similar mechanism to lactase deficiency which creates osmotic diarrhea

Answer 298

Helps to regulate PFK-1 (glycolysis) and fructose 1-6 biphosphetase (gluconeogenesis) Insulin activates PFK2, which then increases PFK1 via fructose 2-6 biphosphetate Glucagon does the opposite **high concentrations of fructose 2-6 biphosphate inhibit gluconeogenesis leading to decreased conversion of alanine and other gluconeogenic substrates**

Answer 299

Bulemia Nervosa Tx: SSRI, nutritional rehab, CBT

Answer 300

used in **sickle cell anemia (esp in frequent pain crises)** mechaism: **increases fetal hemoglobin (HbF).** This confers protection against the polymerization of sickle cells.

Answer 301

Cardiac amyloidosis due to deposition of AL deposits (Ig light chain) **blue arrow** is normal myocardial cells **black arrow** is an area of the myocardium infiltrated with amorphous and acellular pink material

Answer 302

It is part of the DNA containing Hepadnaviridae and consists of a spherical double layered particle that has a nucleocapsid pore covered by an outer lipoprotein envelope (containing surface HBsAg) ## Footnote **\*A partially circular DNA molecule that replicates through reverse transcriptase\*** **Unique in the fact that it is a DNA virus that replicates via reverse transcription**

Answer 303

The vascular watershed area of the **nasal septum** known as **Kisselbach plexus** This region has several significant anastamoses: 1. septal branch of anterior ethmoidal artery 2. lateral nasal branch of sphenopalantine 3. septal branch of superior labial artery (branch of the facial artery

Answer 304

This is a **hydrocele**. Specifically, a c**ongenital-communicating hydrocele**, a collection of peritoneal fluid within the tunica vaginalis. This happens because the **processus vaginalis remains patent** and allows peritoneal fluid to accumulate in the tunica vaginalis **Very common in newborns and presents as painless scrotal swelling that transluminates**

Answer 305

**Linezolid**: used to treat gram + bacteria, particularily VRE and MRSA Linezolid has MAOI activity and thus when combined with a pts SSRI, they can present with serotonin syndrome (usually need two meds to get this syndrome)

Answer 306

This patient has **sickle cell anemia** and is presenting with a **vasoclussive episode of dactylitis (hand-foot syndrome)** the repeated sickling of RBC leads to an intra and extra-vascular hemolysis resulting in an increased billirubin and lactate dehydrogenase as well as a **DECREASED HAPTOGLOBIN** (haptoglobin binds circulating hemoglobin and reduces excretion of free hemoglobin) This is a common presentation of SCD in young patients

Answer 307

Pregnancy and the use of oral contraceptives predispose women to gallstone formation with 5-10% of all pregnancies developing cholelithiasis **Estrogen --\>** upregulate HMG-CoA reductase activity, which causes **bile to be supersaturated with cholesterol** **Progesterone --\> reduces bile acid secretion and slows gallbladder emptying** \*when the gallbladder is hypomobile or there is more cholesterol in the bile, there is a prediliction of the bile to precipitate

Answer 308

Dilusions or hallucinations for \>2 weeks in the absense of a mood episode (manic or depressive) (vs schizophrenia that is lasting \>6 months and lacks significant mood symptoms)

Answer 309

Sitting --\> base of R lower lobe (can be left too but less likely Laying flat --\> posterior segment of the right upper lobe (and superior segment of lower lobe)

Answer 310

This is a **glaucoma** med that is a **prostaglandin** **analog** that i**ncreases outflow of aqueous humor** via uveoscleral outflow Remember that **open angle glaucoma** is caused by i**ncreased production of aqueous humor and decreased secretion** through canal of Schlemm and Uveoscleral outflow tract. It is characterized by **increased intraoccular pressure.** The symptoms develop over decades and involve loss of peripheral vision

Answer 311

Side effects are **muscle aches and hepatotoxicity. _Need to check LFTs before starting a statin._** Increased LFTs (more than three times the upper limit) only occurs in 1% of pts put on statins but can be eliminated with cessation of the drug

Answer 312

**Gastric erosions:** are mucosal defects that **do NOT penetrate through the muscularis mucosa.** These tend to occur in acute errosive gastropathy that can be caused by NSAIDS, curling, cushing, smoking, ETOH **Gastric ulcers:** penetrate through the muscularis mucosa into the submucosa. Causes are NSAIDS (inhibiting prostaglandin synthesis), H.Pylori

Answer 313

fistula between gallbladder and GI tract --\> air in biliary tree --\> passage of gallstones into GI tract --\> obstruction of iliocecal valve by stone

Answer 314

Contraction results in shortening of H and I bands and between Z lines **(HIZ shrinkage)** The A band remains the same length **(A band is Always the same length)**

Answer 315

responsible for gestational diabetes

Answer 316

1. Entacapone, Tolcapone (COMT inhibitor, keeps levodopa in periphery) 2. Carbidopa (prevents DOPA carboxylase from breaking down levadopa) 3. Bromocriptine, Pramipexole (Dopamine agonist in CNS) 4. Tolcapone in CNS (COMT inhibitor that crosses BBB, keeps Levodopa from being broken down)

Answer 317

lengthens the slow diastolic depolarization phase by inhibiting the I_funny channels (mixed Na/K inward current) Accounts for automaticity of SA and AV nodes. The slope of phase 4 in the SA node determines HR

Answer 318

This is a **Kayser-Fleischer ring** and is associated with **Wilson's disease**. The rings are caused by the deposition of copper within the basement membrane of the cornea Wilson's disease is a rare autosomal resessive disease that affects individuals 5-40 years old. The mutation on chr 13 (ATP7B gene) hinders copper metabolism. Eventually the copper leaks from the injured hepatocytes and enters the circulation where it **can deposit in the cornea and the basal ganglia** **tx: D-penicillamine**

Answer 319

multiple motor and \>1 vocal tic (not necessarily concurrent) that lasts \> 1 year The vocal tics can be coughing, grunting, throat clearing, to blurting out inappropriate comments (10-20% of pts) typically presents in boys 6-15 comorbid ADHD and OCD is common

Answer 320

Pts who receive an abnormal gene from their father tend to develop the disease at a younger age. Common in Huntington, Fredrich Ataxia, Mytonic dystrophy, and Fragile X syndrome CAG repeats increase during spermatogenesis in the **HTT gene on chr 4** **The higher number of CAG repeats corresponds to more severe sx** **HD is transmitted in AD fashion with COMPLETE PENETRANCE**

Answer 321

HSV-1 encephalitis: infection of the oropharynx travels through the olfactory tract or trigeminal nerves to invade the temporal lobes Pt gets primary oropharynx infection that travels retrograde down the trigeminal nerve. It lives in the trigeminal ganglion. Upon reactivation, it can travel back down anterograde to the face or can continue travel up the nerve into the brain causing encephalitis

Answer 322

Presence of substance A is required for the full effects of substance B ex: cortisol on catecholamine responsiveness

Answer 323

This pt has **cyanide poisoning** that presents with reddish skin discoloration, tachnypnea, HA, tachycardia, N/V, confusion, weakness Lab would show **lactic acidosis with narrowing of venous PO2 gradient** (resulting from inability of tissue to extract O2) Tx: Inhaled **Amyl Nitrate --\> oxidises Fe2+ to Fe3+** generating methemeglobin. This is incapable of binding oxygen but **can bind cyanide**, which will free it from cytochrome oxidase and limit its toxic effects **(can also give thiosulfate and hydroxycoabalin (a precursor for B12))**

Answer 324

This is a uric acid stone that often appear rhomboid in shape. They are radiolucent. Risk factors include low pH and low urine volume. Pts with chronic diarrhea have increased loss of bicarb and are in a state of chronic metabolic acidosis. The kidneys compensate by increasing H secretion into tubule and increasing bicarb reabsorption in collecting ducts. This makes urine acidic and increases conversion of soluble urate salts into insoluble uric acid

Answer 325

partial, complete, or progressive obstruction of extrahepatic bile ducts. Usually infants appear healthy at birth and then undergo progressive jaundice, dark urine, acholic (pale) stools due to excessive renal excretion of bilirubin and lack of bile Labs: elevated direct bilirubin (direct =conjugated)

Answer 326

Anterior: Left Atrium Posterior: Descending Aorta

Answer 327

Above dentate --\> internal iliac/ inferior mesenteric Below dentate --\> inguinal As a general rule of thumb, the lymph drainage follows the blood supply in this area

Answer 328

Hereditary Spherocytosis: often present with increased indirect billirubin, anemia, reticulocytosis. The blood smear will show large round cells without any central pallor. This is an AD disease that causes defective membrane binding to due ankryin, spectrin, band 3 mutations **\*\*The most important lab finding is an increase in mean corpuscular hemoglobin concentration MCHC\*\***

Answer 329

The pt has **small cell carcinoma of the lung** from his smoking habit. This cancer often presents with **paraneoplastic syndrome where there is excess ADH produced --\> SIADH** This leads to **increased water reabosrption** by the kidney leading to a temporary subclinical hypervolemia. This **shuts down RAAS** and stimulates natruetic peptides which then dump Na in urine **(naturesis**). As a result SIADH pts have normal volume with low sodium **= euvolemic hyponatremia** **Volume overload sx are NOT seen**

Answer 330

used to treat serotonin syndrome (5HT-2 receptor antagonist)

Answer 331

**Doxazosin** (alpha-1 blocker) Relaxes smooth muscle leading to decreased peripheral resistance and lowering BP. Also relaxes smooth muscle of bladder neck and prostate leading to a decrease in urinary obstruction caused by BPH

Answer 332

**Neimann-Pick Disease** is an AR disease caused by deficiency in sphingomyelinase causing excess spingomyelin. These cells look enlarged and foamy. These lipid-layden foam cells accumulate in the spleen and liver causing **hepatosplenomegaly** and CNS causing **neurodegeration** ## Footnote **Death by age 3** **Also have cherry red macular spot**

Answer 333

**Renal papillary necrosis** due to underlying sickle cell trait symptoms usually involve dark or bloody urine with colicky flank pain due to uteral obstruction (with no CVA tenderness) Can also be seen in pts with **DM, analgesic nephropathy, or severe obstructive pyelonephritis** **SAAD papa with Papillary necrosis** **S: sickle cell disease/trait** **A: acute pyelonephritis** **A: analgesics (NSAIDS)** **D: DM**

Answer 334

In Parkinsons there is degeneration of the nigrostriatal pathway. This leads to excessive excitation by the globus pallidus by the subthalamic nucleus, which in turn causes excessive inhibiton of the thalamus. Reduced acvitiy of the thalmus on the cortex results in bradykinesia and ridgitiy **DBS of the globus pallidus internus or subthalamic nuclei inhibits firing of these nuclei**, which eventually results in thalamo-cortical disinhibition with improved mobility (think want to take direct leash off of the thalamus and let it fire)

Answer 335

This is a very rare mitochondrial myopathy, where abnormal mitochondria accumulate under the sarcolemma of muscle fibers This is one of the red ragged fiber diseases \*Remember that sperm mitochondria are NOT pass into the ovum during fertilization and thus all mitochondrial diseases are passed through the maternal lineage

Answer 336

jaundice **_Portal Hypertension_** esophageal varicies splenomegaly ascites caput medusa anorectal varices **_Hyperestrinism_** testicular atrophy spider angioma gynecomastia

Answer 337

**somatic --\>** mutations that arise from mitotic errors AFTER fertilization and propagates through multiple tissues or organs. CANNOT be passed on to next generation. Ex: leukocytes with 40% 46X and 60% XX seen in Turner syndrome **germline --\>** mutation only in egg or sperm cells. The mutation would be in **EVERY** **cell** of the body

Answer 338

1. situs invertus 2. chronic sinusitis **3. bronchiectasis (photo)** **Also have primary ciliary diskinesia --\> impaired sperm motility (infertile)**

Answer 339

1. TCA (**amitriptyline**) 2. Antihistamines (**diphenhydramine**, doxylamine) 3. 1st gen antipsychotics (**chlorpromazine**) 4. 2nd gen antipsychotics (**clozapine**) 5. Antiparkinsons drugs (**benztropine**, trihexyphenidyl) 6. Belladonna alkaloids (**atropine**)

Answer 340

B-hcG has a very similar structure to LH, so it can stimulate the LH surge by inducing ovulation. This is done when the follicle appears mature but will not be released due to the PCOS

Answer 341

an agonist at the GABA-B receptor is effective as a monotherapy for the treatment of spasticity secondary to brain and spinal cord disease, esp MS -can be used for muscle spasms (low back pain)

Answer 342

history of prior suicide attempt

Answer 343

**_direct vascular smooth muscle relaxation resulting in:_** 1. vasidilation of peripheral veins and arteries, **predominently vasodilation** 2. decreased LV wall stress due to **decreased preload (decreased LV end-diastolic volume and pressure)** **3.** modest r**eduction in afterload** due to arterial vasodilation 4. mild coronary artery dilation and reduction of coronary vasospasm

Answer 344

Often arises from **injury to the Tibial nerve** at the popliteal fossa can cause **weakness of foot plantarflexion**. Weakness on foot **inversion** and **toe** **flexion** \*Results in **sensory loss over sole of foot** too\*

Answer 345

Rhizopus species Tends to affect the paranasal sinuses Form broad nonseptae hyphae that branch at wide 90 decree angles Compare to Aspergillus fumigatas BELOW that branch at 45 degrees (V shaped branching

Answer 346

Gallstone obstruction of the cystic duct in 90% of cases. Ingestion of fatty food then causes contraction of the gallbladder and results in a colicky pain US is the best diagnosis of this however **nuclear medicine hepatobiliary screening can be an alternative means when US is inconclusive** (this is a more precise way to dx acute cholecystitis). Tracer is injected IV and taken up by hepatocytes and dumped into bile. Images are taken throughout IF you are using an US however, cholecystitis is more likely to **show gallbladder wall thickenin, pericholecystic fluid and positive sonographic murphy sign**

Answer 347

Gout via decreased renal excretion of uric acid, leading to elevated blood levels and increased risk for acute gouty arthritis

Answer 348

**Liver** via stimulation of gluconeogenesis and glycogenesis. Both actions lead to an overall increase in liver protein synthesis

Answer 349

Vasculitis of medium sized arteries that affects children \<5 years old. Occurs most often in children of Asian descent Need fever \>5 days and 4 of 5 sx below A serious complication is **coronary artery aneurysms** **Can treat kids with ASA!!!!**

Answer 350

**Anterior compartment --\>** foot extensor muscles, anterior tibial artery, deep peroneal (fibular) nerve **Lateral Compartment --\>** superficial peroneal nerve **Deep posterior compartment --\>** tibial nerve, posterior tibial artery and vein, peroneal artery and vein **Superficial posterior compartment --\>** no vessels, gastroc and soleus

Answer 351

**valine (hyrophobic) for glutamic acid (hydrophilic)** - The incorporation of this abnormal beta-globin protein into hemoglobin results in the formation of HbS - HbS polymerizes at low oxygen tension causing sickling and hemolysis resulting in vascular occlusion

Answer 352

simultaneously measures exposures and outcomes (also known as a prevelence study) has a "snapshot" design that is frequently used in surveys

Answer 353

Damage to the **subthalamic nucleus** can decrease excitation of the globus pallidus internus thereby reducing inhibition of the thalamus and results in hemiballismus (wild, involuntary large amplitude flinging movements involving the proximal limb. -most commonly occurs in the setting of a lacunar stroke

Answer 354

Remember amiodarone is 40% iodine by weight am**IOD**arone can cause a lot of alterations in thyroid function

Answer 355

hyperadrenderic mainfestations in severe thyrotoxicosis reflect a generalized increased sensitivity to catecholamines propanolol: 1. reduce the pts HR and general feelings of anxiety 2. reduces conversion of T4 --\> T3 by inhibiting iodothyronine deiodinase

Answer 356

All three have the ability to remove mismached nucleotides by their **3' --\> 5' endonuclease** (**proofreading**) **ONLY DNA Pol 1 has a 5'--\>3'** exonuclease activity

Answer 357

selevtive alpha-1 adrenergic agonist that causes marked arterial vasoconstriction causing an increase in vascular resistance and blood pressure It also decreases pulse pressure and HR and SV (via a baroreceptor-mediated increase in vagal tone

Answer 358

after birth when the umbilical cord clamps and there is decreased pulmonary vascular resistance, the right atrial pressure lowers and the left atrial pressure rises. This pushes the septum primum against the sptum secundum, closing the foramen ovale. Incomplete fusion occurs in 25% of adults resulting in a PFO This usually remains closed as pressure on the left is higher than the right. Conditions such as valsalva release can cause a transient increase in R atrial pressure that can cause a right to left shunt. This is particularily concerning in patients with hypercoagulability

Answer 359

This patient has Hairy Cell Leukemia and the smear will present with lymphocytes with cytoplasmic projections. This is classically seen in older males and it infiltrates the bone marrow and reticuloendothelial system Classically causes dry tap on aspiration due to marrow fibrosis. Present with massive splenomegaly

Answer 360

The appearance of vacuoles and phospholipid containing densities within mitochondria generally signifies irreversible injury Simple mitochondrial swelling is a reversible process Anything that damages the membrane of the cell or mitochondria results in irreversible damage

Answer 361

MMPs are secreted by several different cell types including fibroblasts, macrophages, neutrophils, synovial cells, and epithelial cells. They are **essential for breaking down collagen and other proteins in the extracellular matrix**. It is important in wound healing as it encourages both myofibroblast accumulation around the wound edges and scar tissue remodeling **When this process happens too much, can see wound contracture**

Answer 362

**Dilated Cardiomyopathy** Also caused by **ABCCCD** **A: Alcohol abuse** **B: wet Beriberi** **C: Coxsackie B** **C: chronic Cocaine use** **C: Chagas Disease** **D: Doxorubicin** D

Answer 363

**This is a decrease in the systolic blood pressure (\>10) during inspiration (normally falls \<10 during inspiration)** **Seen in cardiac tamponade, croup, asthma, OSA, pericarditis** The fluid in the pericardium causes limitation of right ventricular expansion that is exacerbated by inspiration when venous return is increased. This leads to a bowing of the interventricular septum toward the left ventricle, decreaing LV end diastolic volume and stroke volume

Answer 364

**1st gen:** end in **en/ine or en/ate** --\> diphenhydramine, dimenhydrinate (dramamine), chlorpheneramine. Remeber these can cross the BBB and cause more significant sedation and cognitive dysfunction. Potentially inappropriate for elderly patients, esp those with preexisting conditions or cognitive impairment **2nd gen:** end in **ADINE** Loratadine, fexofenadine, deslortadine

Answer 365

Leads to fermentation of undigested lactose by the gut and increased production of short-chain fatty acids that **acidify the stool** (decrease pH). Hydorgen gas is also produced, which **increaes breath hydrogen content** Also causes **osmotic diarrhea** due to high amounts of undigested lacose in the feces.

Answer 366

vaccines containing the polysaccharide alone are ineffective in children under 2 due to their immature humoral immunity. Therefore, the polysaccharide is conjugated to a carrier protein to amplify the patients humoral response against the polysaccharide through T-cell recruitment. The carrier protein is from the Tetanus Toxoid protein or outer membrane of Neisseria Meningitidis. **Immunity is then increased via T-cell depednent stimulation of B lymphocytes and the production of memory B lymphocytes**

Answer 367

**Apocrine:** cells secrete via membrane bound vesicles --\> mammary glands **Holocrine:** cell lysis releases entire contents of the cytoplasm and cell membrane --\> sebaceous glands **Merocrine:** cells secrete via exocytosis --\> salivary glands, apocrine sweat glands (stupid, I know), eccrine sweat glands

Answer 368

**presentation is DUMBBELSS** (diarrhea, urination, miosis, bronchospasm, bradycardia, excitation of skeletal muscles, lacrimation, sweating, salivation) If give **Atropine** --\> reverses muscarinic effects (competitive antagonist) but NOT address nicotinic effects and thus can still lead to muscle paralysis If give **Pralidoxime** --\> reverses both muscarinic and nictonic (only effective in regenrating AChE if given early)

Answer 369

AR disorder caused by **defective or deficient Gp IIb/IIIa** on platelet surfaces that typically present in childhood with mucocutaneous bleeding (increased bleeding time) Normally, this is a target of **Abciximab**

Answer 370

**Glycine-X-Y--Glycine-X-Y...** Every third AA is glycine. X= proline Y=hydroxyproine or hydroxylysine

Answer 371

Central responds to Desmopressin Partial nephrogenic partially responds Complete nephrogenic does not respond at all

Answer 372

Persistent Depressive Disorder (dysthymia) - need chronic depressed mood for 2 years - no symptom free for \>2 months If it is pure dysthmic syndrome, the criteria for major depressive episode was never met

Answer 373

Fructose-1-phosphate because it bypasses a few major steps in metabolism allowing for it to be faster specifically, it bypasses PFK, the rate limiting step of glycolysis As a result, fructose is metabolized by the liver faster than other monosaccharides and is rapidly cleared from the bloodstream following dietary absorption

Answer 374

-Prior to storage, packed RBC are **mixed with citrate anticoagulant. Infused citrate can chelate calcium**, causing hypocalcemia (pins and needles pt is experiencing) This is more likely when a pt receives 5-6 liters in a 24 hour period

Answer 375

**Vitamin A toxicity** **Acute**: N/V, verigo, blurred vision **Chronic:** alopecia, dry skin, hepatic toxicity and enlargement, arthralgias, pseudotumor cerebri **Teratogenic:** cleft palate, cardiac enlargement, fetal death if in first trimester (reason why need prove two different types of contraception before isotretinoin therapy)

Answer 376

Need to remember that the nerves (meissner and aurbach plexus) migrate CAUDALLY (towards tail)...so the **rectum is ALWAYS** involved and the **sigmoid colon is involved 75%** of the time This migration happens caudally along the vagal nerve Newborns with Hirschprung fail to pass meconium within 48 hours of birth

Answer 377

This is destruction of meyers loop, an results in **Left homonomous superior quadrantanopia "pie in the sky"**

Answer 378

**Lysosomal digestion of the tissue.** The brain undergoes liquifactive necrosis The image shows a secton of the brain with a cystic cavity surrounded by gliosis. **Release of lysosomal enzymes from these neurons results in degredation of the tissue in the ischemic region**. Phagocytic cells move into the area and and remove the necrotic tissue and leave a cavity and astocytes proliferate and create a glial scar **(This whole process of complete digestion of necrotic tissue with formation of a gliosis =liquifactive necrosis)**

Answer 379

This is an **Dandy Walker Malformation** **--\> absence or malformation of the cerebellar vermis (red) and cystic dilation of the 4th ventricle (blue)** with posterior fossa enlargement Pts often present with skull enlargement and developmental delay in infancy. Non-communicating hydrocephalus may occur due to atresia of the foramina leusha and magendie resulting in sx of increased ICP

Answer 380

non-selective b-adrenergic agonist that INCREASES cardiac contractility (by acting on B1) and binds to B2 to decrease vascular resistance B1=B2

Answer 381

**sulfonylurea** (close K channels, cause depolarization, Ca enters, release insulin) This would increase C-peptide levels (indicating that it was endogenous insulin NOT exogenous)

Answer 382

**Partial opiod agonist** that has low efficacy for mu-opioid receptors, but it binds with high affinity (potency) and can prevent binding of other medications. Essentially it acts as an opiod receptor antagonist in the presence of other opioids and can precipitate **WITHDRAWL** in opioid pts with chronic pain

Answer 383

AD, CTG trinucleotide repeat expansion in the DMPK gene --\> abnormal expression of myotonin protein kinase shows anticipation **Sx: myotonia, muscle wasting, cataracts, testicular atrophy, frontal balding, arrhythmia** **"My Tonia, My Testicles, My Toupee, My Ticker"**

Answer 384

an arrangement where a payer (employee, individual or government entity) pays a fixed, predetermined fee to cover all the medical services required by a patient. Capitation is the payment structure underlying HMO provider networks There is an incentive for the provider and the patient to reduce expeses usually by restricting patients to a limited number of providers

Answer 385

Premature infants born at \<32 weeks are at significant risk of surfactant deficiency. Corticosteroids such as dexamethasone or betamethasone increase surfactant by accelerating maturation of type II pneumocytes. -These meds are administered to pts who are at risk of preterm labor to decrease the chance of respiratory distress and mortality.

Answer 386

Right Atrium: Mean 1-5 Right Ventricle: Sys: 15-30, Dias: 1-6 Pulmonary Artery: Sys: 15-30 Dias 6-12 Left Atrial/PCWP/LVEDP: Mean 6-12

Answer 387

**Glucose --\> sorbitol (via aldose reudctase) --\> fructose (sorbitol dehydrogenase)** Sorbitol accumulates in tissues where sorbitol dehydrogenase is low or in long standing hyperglycemia where there is high levels of sorbitol. Sorbitol cannot cross the cell membrane and is thus trapped in cells. Sorbitol increases osmotic and oxidative stress and contributes to the pathogenesis of retinopathy **Basically, glucose overwelms the pathway causing intracellular sorbitol accumulation**

Answer 388

Emboli that start in the venous circulation and end up lodged in the arterial circulation **via a patent foramen ovale or atrial septal defect** (DVT --\> Middle Cerebral Atery infarct) Wide and fixed splitting (no change with respiration) of the second heart sound This can happen as a transient event such as coughing or during early ventricular systole or defecation

Answer 389

The membranous segment of the urethra (right after the prostate) is relatively unsupported by the adjacent tissues and is one of the weakest parts ## Footnote **\*This bulbomembranous junction is often injured\***

Answer 390

**Folinic acid (leukovorin)** Can reverse MTX toxicity if given early. It does not require DHFR to be converted to THF and is therfore unaffected by MTX Leukovorin is given during high dose methotrexate to **"rescue" bone marrow and GI and other tissue** from MTX toxicity Additionally, it **potentiates 5FU** (used in colorectal cancer regimens)

UWorld first half Flashcards

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