Random Missed Uworld - Week 1 Flashcards

Question

Obstructive lung disease is characterized by ...(*lung volumes)* What are causes of obstructive lung disease (2): complications..

Answer 1

Obstruction of air flow --\> air trapping in the lungs/*airways close prematurely at high lung volumes =* INC RV DEC FVC PFTs: DEC FEV1, DEC FVC -- DEC FEV1/FVC ratio, V/Q mismatch Examples: - anatomical obstruction, such as chronic bronchitis, where hyperplasia of mucus-secreting glands in bronchi, anatomically decrease the amt of air that is able to leave the lungs * blue bloater* - DEC in lung wall elasticity, such as in emphysema, due to destruction of interalveolar wall --\> compression during expiration, and unable to breath air out * barrel-shaped chest, pink puffer*

Answer 2

Hallmark for sarcoidosis: young, African-american female, presenting with SOB, cough, chest pain, **UVEITIS**, skin lesions, **_lofgren syndrome_** (*acute* *presentation:* **bilateral hilar adenopathy**, erythema nodosum, polyathralgia/polyarthritis) Imaging: bilateral hilar adenopathy, pulmonary reticular infiltrates Labs: **INC ACE, INC Ca2+** **_non-caseating_ granulomas (_high presence of T-lymphocytes CD4+_)**

Answer 3

it is a form of PRIMARY CILLIARY DYSKINESIA [**_dynein_** **arm defect affecting cilia function**] *_Clinical pres:_* **Sinus Invertus**, chronic sinusitus, bronchiectasis [due to impaired mucociliary clearance], infertility Occurs due to mutations that impairs the structure or function of cilia Inheritance is **auto recessive** via wide variety of mutations

Answer 4

less breathing = holding PCO2 in = INCREASED levels of PC02 more breathing = more expelling = DEC CO2 levels (ie- panic attack) If it is acute process (such as heroin overdose), then there will be uncompensated respiratory acidosis: HI PCO2, low pH (nl: 7.35-7.45), nl to mildly elevated bicarb (renal compensation requires at least 24 hours of persistent respiratory acidosis)

Answer 5

**Dynein**, responsible for retrograde travel (+ --\> -) helps _ESTABLISH_ infection (goes towards cell body) **Kinesin**, responsible for antegrade travel (- --\> +) helps infection _REOCCUR_, taking the virus back to the skin surface

Answer 6

Sensitivity = how likely a person WITH a disease will test positive [*less chance of false negative, correctly identifies those with a disease*] Specificity = how likely a person WITHOUT a disease will test negative [*less chance of false positives, correctly identifies ppl without dz*] **Remember: SNOUT and SPIN** SeNsitiivty helps you rule OUT a dz SPecificity helps you rule IN a dz

Answer 7

**FF = GFR / RPF** Renal plasma flow could be determined from the renal blood flow via, ***RPF = (renal blood flow)\* (1-hematocrit)***

Answer 8

Both are used to detect **DNA-binding proteins** *_examples include_***: transcription factors, steroids, thyroid proteins, vitamin D receptor, retinoic acid R, DNA transcription and replication proteins, etc...** expression cloning is a type of DNA cloning, where the signal for translation and transcription are included in the clone portion; allows for the use of bacteria in the process as a mRNA is able to be made into a cDNA which then can be inserted in a plasmid, made and then identified using a DNA probe.

Answer 9

IgM --\> IgE or IgG requires **IL- 4** switch to IgA requires **IL-5** **remember: HOT T-BONE stEeAK** IL 1- fever (hot, ) IL 2- (stimulates **T** cells - helper, cytotoxic, regulatory) IL 3- stimualtes **bone** marrow growth and differentiation IL 4 - induces differentiation of TH0-TH2, promotes growth of B cells and enhances class switch to IgG and Ig**E** IL 5 - promotes differentiation of B cells. Enhances class swith to Ig**A** stimulates growth and differentiation of **e**osinophils IL 6 - stimulates aKute phase protein production, and fever

Answer 10

digoxin lithium theophylline warfarin *"THE WAR Does Last"*

Answer 11

recurrent episodes of anemia, jaudice and painful swelling of the hands and feet Autosomal Recessive inheritance

Answer 12

Gout is caused by tissue deposition of monosodium urate crystals Elevated uric acid levels are a known risk factor for gout -one thing that could cause **hyperuricimia**, in via increased purine metabolism **PRPP synthease** is the enzyme resposible for the activated ribose needed to make de novo synthesis of purine and pyramidine nucleotides

Answer 13

***_SAD PUCKER:_*** S: suprarenal/adrenal glands A: aorta and IVC D: duodenum (2nd and 3rd part only) P: Pancreas (minus tail) U: Ureters C: Colon (desending and ascending) K: Kidneys E: Esophagus (thoracic portion) R: Rectum (partially) Secondary means that they are originally suspended in the mesentary then move to the retroperitoneal space

Answer 14

In a standard table, it is equal to = AD/BC (attach image) Only odds ratio should be used in **case-control studies**

Answer 15

Anaphylactic and atopic reactions are **type I** hypersensitivity reactions. Free antigen cross links with IgE on PRE-SENSITIZED mast cells and basophils --\> cross links triggers immediate release of **vasoactive amines** that act **POSTcapillary VENULES** (histamine, etc) Reaction is RAPID due to **PREFORMED antibody IgEs** Delayed response follows due to production of arachidonic acid metabolites (leukotrinenes)

Answer 16

**1. Hyperacute:** *within minutes* _PRE-EXISTING_ **RECPIENT *_IgG antibodies_*** react to donor antigen (type II hypersen, _activate compliment)_ **2. Acute:** * weeks - months* cellular: **CD8+ T** cells activated against donor MHCs humoral: type II hypersensitivity (ab develop against donor) **3. Chronic** *months to years* **CD4 + T** cells respond to recipeint APC presenting donor peptides, including allogenic MHC Both cellular and humoral components --\> proliferation of vascular smooth muscle and parenchymal fibrosis; dominated by arteriosclerosis **4. Graft versus host disease** *varies* GRAFTED immunocomponent _T cells proliferate_ in the immunocompromised host and reject host cells with foreign proteins

Answer 17

Excretion = total filtration - total tubular reabsorption total filtration = GFR \* [plasma] ***inulin clearance could be used to estimate GFR*** * Creatinine could also be used BUT it will be slightly over estimated since, creatinine is moderately secreted by the renal tubules* * FF = GFRXRPF --\> GFR = RPF/FF*

Answer 18

CSF is made in 4 choroid plexus found in each ventricle Choroid plexus is made of epedymal covered out growths of pia, they are fenestarted and act as teh CSF/Brain barrier Lateral ventricles, via the foramen of Monroe --\> third ventricle, then via the cerebral aqueduct of Sylvus --\> 4th ventricle --\> subarachnoid space via 3 openings (2 lateral foramen of luschka or foramen of Magendie) CSF is then returned to the venous circulation via arachnoid villi (granulations)

Answer 19

Niacin is either obtained through dietary intake or endogenously made by **TRYPTOPHAN** **Deficient state:** In developing countries: in communities where corn is the staple food (niacin is bound and not absorable) In devloped countries: nutritional deficiency states such as alcoholics, chronic illness; also in those with **carcinoid syndrome**, prolong **isonizaid** therapy, **Hartnup dz**

Answer 20

They are recommended for use with anemia related to chronic kidney disease; reduce the need for blood transfusions and the complications that could lead to prolong anemia [cardiac dysfunction, weakness, mental status changes...] However, they could an **increase in the viscosity** of the blood which can lead to *_thromboembolic events*_ (vascular graft thrombosis, stroke..); also could lead to _*increase of blood pressure_*, due to possible activation of erythropoeitin receptors on the walls of vascular endothelium and smooth muscle

Answer 21

**1. INC stress** - loss of urethra support and inc intraabdominal pressure \> sphincter pressure --\> *_leakage with laughter, cough, sneezing, etc_* **2. Urge - detrussor overactivity** --\> sudden, overwhelming and frequent need to empty bladder **_(could be due to MS!_** *lose CNS inhibition of micturition* **3. Overflow** - impaired detrussor contractility or obstruction at bladder outlet --\> *_involuntary dribbling of urine and incomplete emptying_*

Answer 22

**Acute myelogenous lekemia**/acute megakaryoblastic leukemia (_before 5 y/o -*m for mini*_) **Acute lymphoblastic leukemia** (usually _after 5y/o_)

Answer 23

advancing age female white, hispanic, asian (AA women have increased bone density and *thus decrease risk*!) - LOW bone density personal/family hx of fractures decreased physical activity **_low_ BMI** poor calcium and vitamin D intake *excessive alcohol and tobacco use* _premature_ menopause **glucocorticoid, anticonvulsant, anticoag, thyroid replacement meds**

Answer 24

cognitive behavioral therapy SSRI, SNRI *benzos are second line, not recommended for chronic anxiety disorder, could be used _temporarily_ while SNRI/SSRI kick in, but are contraindicated in pt with a history of substance abuse*

Answer 25

**PBC** is an **autoimmune** destruction of *_intrahepatic bile ducts and interlobules,_* typically, it is _middle aged women_, presenting with fatigue, prutitis, jaundice, (*pancreatic type of sx)* + **XANTHOMAS** increased inflammation, **granulommas** and increased **lymphocyte infiltration** **+ANA**, and many times associated with other autoimmune conditions

Answer 26

Pork tapeworm **neurocyticercosis** endemic in south and central america presents with **seizures** and **cystic brain** lesions in immunocompenent patients, transmitted via i**ngestion of eggs in stool from infected individuals in infected _undercooked pork_**

Answer 27

in MCA occlusions, we could expect **CONTRALATERAL** *_hemiparesis*_ and _*hemisensory loss_* involving the _face and upper limb_ If the occlusion were to occur in the dominant hemisphere (usually left), we can possible also see *expressive and receptive aphasia due to infraction of broca's and wernike's areas*. Speech areas are usually located in the dominant side of the brain

Answer 28

**DNA polymerase I** is the _only one_ that has this ability - thus it can **descise RNA primers and replace them with DNA during DNA replication**

Answer 29

**12- 24 hours** after irreversible ischemic damage *_neurons containing:_* ***_esinophilic_* cytoplasm** **pyknotic nucleus/shrunken and basophilic** **_loss of Nissl substance_**

Answer 30

3 positive waves: a, c and v 2 negative waves: x and y a = right atrial contraction (absent in a. fib) c = bulging tricuspid into right atrium during right ventricular contraction/systole x = R atrial relaxation v = continued inflow of venous blood y= *passive* emptying of r. atrium after tricuspid valve opening / abrupt decrease in pressure

Answer 31

Thickening and calcification of the pericardium slow and progressive dyspnea, chronic edema and ascites On the jugular venous pressure tracing, you would get a **_rapid Y descent_ that becomes deepr and steeper with inspiration** Causes: radiation to the chest, cardiac surgery and _tuberculosis_ [*key: pt immigrating from an area TB endemic!*] Contrast with hypertrophic cardiomyopathy heart on CT: dyspnea and changes to the jugular pressure wave, **prominent a wave** - CT will not show thickening or calcification of the pericardium (could show thickening of the interventricular space) In ischemic heart disease - you might see calcifications of the coronary arteries and aorta

Answer 32

Major early biochemical change is cessation of a_erobic glycolysis_ and _initiation of anaerobic glycolysis_...this occurs within minutes, **so almost immediately/60seconds, the affected portion of the myocardium stops contracting** --\> stunned myocardiocytes you will get depletion of ATP, and INC ADP, AMP and adenosine, INC of lactate..**adenosine** can leak out of the cell and **_act as a vasodilator to help meet demand_** ischemia **less than 30 minutes** causes **REVERSIBLE** changes, the myocardium will return to normal hours - days _Ischemia \> 30 minutes --\> IRREVERSIBLE injry_

Answer 33

Morphine (one type of opiate), binds mu receptors, as an agonist modulates the synpatic transmission, by **opening K+ channels and closing Ca2+ channels** --\> _decrease synaptic transmission_ ***_--\> inhibits release of Ach, NE, 5HT, glutamate and substance P_*** by acting on mu R in the gut - it could cause constipation; could also cause smooth muscle contraction at the Sphincter of Oddi --\> spasms and increase in common bile duct pressures, rarely leading to biliary colic

Answer 34

survival prognosis of **\< 6 months** WITH *advanced metastatic cancers or terminal illness* requires documentation proving irreversible decline in clinical and functional status focuses on comfort and quality of life, with multidisciplinary team, within various different settings (home, nursing, specialized)

Answer 35

Reflex should activate biceps brachi tendon that passes through the cubital fossa --\> activates the muscle receptors that communicate via the musculocutaneous nerve with lower motor neurons in the **anterior horn of C5-C6** **C5-C6 also control the brachioradialis reflex** **Stronger reflex?? Upper motor neuron lesion** **Absent/weak reflex?? lower motor neuron @ spinal cord**

Answer 36

C4 - shoulder/scapula elevation C5- shoulder abduction C5,C6 - elbow flexion, wrist extension C7 - elbow extension, finger extension C8 - wrist flexion, finger flexion T1 - finger abduction

Answer 37

Usually, with oxygen, pyruvate preferentially converts to acteyl coA by **pyruvate dehydrogenase** then acetyl coA could enter the mitocondria and udnergo TCA Under **HYPOXIC** conditions, there is *intracellular accumulation of \*_**NADH\***_* --\> _inhibits pyruvate dehydrogenase_; and thus increased pyruvate --\> **LACTATE by _lactate dehydrogenase_** This allows the **regeneration of NAD+,** from NADH, which allows for *_anaerobic_* glycolysis to continue. With significant tissue ishcemia, lactate begins to accumulate in the circulation --\> lactic acidosis SX: hyperventilation (try to eliminate CO2), via induced compensatory respiratory alkalosis

Answer 38

undercooked groud beef Could cause bloody diarrhea, and lead to hemolytic-uremic sydrome (**HUS**) Elaborates a **Shiga-Like toxin** (*_phage encoded_*) capable of inhibiting protein synthesis in colonic mucosal cells and renal endothelial cells *production _enhanced by iron deficiency_* **INACTIVATE 60S** ribosomal subunit --\> inhibition of protein synthesis and eventual cell death UNABLE to ferment SORBITOL DOES NOT PRODUCE GLUCORONIDASE Unlike enteroinvasive Ecoli, EHEC doesNOT invade intestinal mucosa Unlike enterotoxigenic E coli (ETEC), ehec does NOT produce health labile toxin or heat-stable toxin

Answer 39

Anthrax **EXO**toxin --\> Edema Factor (EF) and lethal factor (LF) **Edema factor INC cyclic AMP** concentration by acting as an adenylate cycalse, causing *_edema and phagocyte dysfunction_* **Lethal factor** - **ZINC** depenent protease that inhibits mitogen activates protein kinase signaling, causing apoptosis and mutli-sys physiologic disruption

Answer 40

Pertusssis toxin and Adenylate cyclase toxin Pertussis toxin: disinhibits adenyl cycalse through **G1 ADP=ribosylation, increasing cyclic AMP levels** *_causes edema and phagocyte dysfunction_* Adenylate cycalse toxin: functions as an adenylate cycalse, increasing cyclic AMP levels, causes edema and phagocyte dysfunction

Answer 41

Botulinum toxin **Blocks **_PRE_**synpatic release of acetylcholine** at the neuromucular junction, resulitng in *_flaccid_* paralysis

Answer 42

Toxin A and Toxin B **Toxin A**- *_recruits and activates neutrophils_*, leading to release of cytokines that causes mucosal inflammation, fluid loss and diarrhea **Toxin B**- *_induces actin depolymerization,_* leading to mucosal cell death, bowel wall necrosis and pseudomembrane formation

Answer 43

Shiga toxin *_Halts protein synthesis_* by **disabling the 60s ribosomal** subunit --\> intestinal epithelial cell death and diarrhea (bloody)

Answer 44

Pyrogenic exotoxin, Streptolysin O and S, DNAse **Pyrogenic exotoxin**- acts as a **superantigen**, inducing fever and shock. associated with scarlet fever, stretococcal toxic shock syndrome **Streptolysin O and S**- damages erythrocyte membranes, causing beta-hemolysis

Answer 45

**Type I interferons (alpha and beta)** - synthesized by most human cells in response to viral infections, bind type I interferon receptors found on infected and neighobring cells and act via autocrine and paracrine signaling. --\> _transcription of antiviral enzymes_ capable of halting protein synthesis (_RNase L, endonucelase that degrades all RNA in the cell)_ and protein kinse R (incativates eIF-2, inhibiting translation intiation). _Enzymes become active ONLY in the presence of DS-RNA (_forms in the infected cell as a result of viral replication = **selectively inhibit virally infected cells** Increase expression of MHC class I on all cells and stimualte NK and cytotoxic T cells **Type II Inteferon gamma-** mainly produced by _T cells_ and _NK cells_; promoate Th1 differentiation, increases expression of *_class II MHC molecules on antigen presenting cells_*, and improves the intracellular killing ability of macrophages **[virally infected cells secrete interferon a and B NOT gamma]**

Answer 46

Trisomy 18 = Edwards Syndrome complete or partical extra copy of chromosome 18, inhertited as a **meiotic nondisjunction** *error in oocyte divison occurs _prior to ovulation_ and fertilization and increases with material age \>35* **sx:** micrognathia, low-set ears, prominent occiput, **rocker bottom feet**, **clenched hands with overlapping fingers**, *(at 18 you're able to rock out!)* cardia anomalies **(ASD, VSD**), genitourinary defects (_horeshoe kidney_), gastrointestinal defects (_omphacelocele, meckel's diverticulum, malrotation_), mental retardation prenatal US findings = fetal growth restrictions Majority affected die in utero, half of life births die before age of 2 weeks, suriving pt have severe intellectual disabilties

Answer 47

unintential weight loos, early satiety - signs for malignantcy + epigastric pain and gastric thickening on CT + abdominal pressure and adnexal mass suggestive of gastric and ovarian invovlement **_Krukenberg tumor_** = primary gastricCA that has metastasized to the ovary histo: nets of **signet ring cells**, appearance due to a **large amounts of mucin displacing the nucleus**

Answer 48

Emergency care STI, contraception substance abuse (most states) prenatal care (most states) *_Emancipated minors - do NOT need parental consent for medical treatment of any kind_* homeless, are a parent, married, military, financially independent, high school graduate

Answer 49

**VIPoma** is a pancreatic islet cell tumor, with excess vasoactive intestinal peptide (VIP) secretion --\> WATERY diarrhea, hypokalemia, achlorhydria syndrome [=_**WDHA syndrome**, **pancreatic chloera**_] **VIP** --\> stimulates pancreatic bicar and chloride secretion, binding to intestinal epithelial cells --\> *_adenylate cyclase activation*_ and _*increased cyclic AMP_* production, causing sodium, chloride and water secretion into the bowel (**secretory watery diarrhea** often \>3L/day) somatostain decreases production of many GI hormones; thus inhibits VIP production.

Answer 50

--\> INC of pancreatic enzymes and bicarbonate, gallbladder contraction and inhibition of gastric emptying DOES NOT cause WHDA syndrome **produced by I cells of the proximal small bowel** mucosa *_in response to fatty acids and amino acids_*

Answer 51

muscle weakness, *_with extraocular muscles most commonly affected_*; pt often experience ptosis and diplopia -- muscle weakness _worsens with activity_ and pt often note that their _sx are worse at the end of the day_ Most have found to have a **thymoma** or **thymic hyperplasia** [thymus is derived from the _THIRD PHARYGEAL POUCH_ as are the inferior parathyroid gland]

Answer 52

People with diseaes of interest (cases) and people without the disease (control) asked about previous exposure to the varibale being studied. The main measure of association is the **exposure odds ratio = what is the odd for someone to have the disease with expsoure vs without exposure**

Answer 53

Shigella (no H2S production ) Salmonella and proteus (H2s production) Pesudomonas aerugionos (ox positive) ***"Shig, Sal, and Ari protest lactose"***

Answer 54

Both are gram negative rods that are fast fermenters of lactose (pink colonies) One distinguishing feature is that E. Coli **indole positive =** ability to covert *_tryptophan to indole_*

Answer 55

Trypsinogen --\> trypsin (via duodenal enterokinase) --\> activate all the other proenzymes and other trypsinogens thus a small amount of activated trypsin can result in an activation cascade **Serine peptidase inhibitor Kazal type 1 (Spink1)** trypsin itself can be its own inhibitor by cleaving other trypsin molecules and rendering them inactive = critical to prevent large amounts of trypsin from forming within pancreatic tissue --\> pancreatitis! *hereditary pancreatitis is a rare disorder that results from mutations invovling the _trypsinogen or SPINK1 genes_ --\> pancreatic autodigestion*