USMLE QBank Review

Question 1

Scaphoid Fractures

Answer 1

• most common of carpal bone fractures
• from fall on outstretched hand
• pain and tenderness in the anatomical snuffbox (scaphoid and trapezium for the floor)
• scaphoid branch of radial artery supplies scaphoid
• fractures = avascular necrosis and nonunion

Question 2

Dupuytren’s Contracture

Answer 2

• slowly progressive fibroproliferative disease of the palmar fascia
• nodules form on the fascia, eventually resulting in contractures that draw the fingers into flexion

Question 3

Opiod analgesics Sideefects

Answer 3

• I.e. Morphine
• can cause contraction of smooth muscle cells in sphincter of oddi leading to spasm and an increase in common bile duct pressures
• cause histamine release leading to vasodilation of blood vessels and itching = can cause hypotension
• constipation
• no direct toxic effect to liver but is metabolized by liver
• increase somatostatin secretion from pancreas

Question 4

Sarcomere

Answer 4

• A band = thick filaments in sarcomere and includes portions overlapped by thin filaments. H band is apart of the A band
• I band = contains the Z line and actin filaments that do not overlap with thick filaments

Question 5

Oral vs Anal drug bioavailability

Answer 5

• when taking an oral drug there is first pass metabolism by the liver which diminshes drug concentration in the systemic circulation
• sublingual drug administration can help bypass first pass metabolism
• rectal drug administration partially bypasses the first pass metabolism because 2/3 of venous drainage goes straight to IVC while the other goes into the portal veinous system
• IV, sublingual, and rectal administration bypasses some or all first pass and allows more drug to reach systemic circulation

Question 6

Anti-Smith Antibodies

Answer 6

• associated with SLS
• smith protein normally complexes with small nuclear RNA in cytoplasm that forms SnRNPs
• autoantibodies directed against SnRNP’s = anti-smith antibodies ==> defect in removal of introns from mRNA

Question 7

RNA types

Answer 7

RNA polymerase 2 = mRNA and snRNA

- other types of RNA are rRNA and tRNA

Question 8

Lesch Nyhan Syndrome

Answer 8

If purine salvage is impaired then the activity of PRPP amidotransferase will increase to supply de novo purine synthesis
- X linked recessive disorder

Question 9

Southwestern Blot

Answer 9

Helps to identify DNA binding proteins
Uses double stranded DNA as a probe (compared to Southern and Northern blot that use single stranded DNA as probes)
-c-Jun and c-Fos are nuclear transcription factors that directly bind DNA via a leucine zipper motif
- Southwestern Blots are used to detect DNA binding proteins like transcription factors, nucleases, and histones

Question 10

Lesch Nyhan Syndrome

Answer 10

If purine salvage is impaired then the activity of PRPP amidotransferase will increase to supply de novo purine synthesis
- X linked recessive disorder

Question 11

Cystic Fibrosis

Answer 11

• mutation in CFTR gene due to phenylalanine deletion
• chronic pulmonary infections, bronchiectasis, pancreatic insufficiency, digital clubbing
• infertility due to absence of vas deferens bilaterally (azoospermia)
• meconium ileus in new born
• CFTR gene mutations are the most common cause of bilateral absence of the vas deferens
• can diagnose with elevated sweat chloride levels and measurement of nasal transpeithelial potential difference

Question 12

Primary Ciliary Dyskinesia

Answer 12

• dynein arm defect - abnormal ciliary motion and impaired mucociliary clearance
• chronic pulmonary infections
• situs in versus
• infertility due to immotile spermatozoa
  Diagnosis
• low nasal nitric oxide levels
• genetic testing

Question 13

Kleinfelter Syndrome

Answer 13

• most common meiosis nondisjunction
• the higher numbers of X chromosomes = more severe manifestations
  Clinical features
• primary testicular failure due to hyalinization and fibrosis of the seminiferous tubules ==> infertility and cryptorchidism
• testosterone deficiency causes eunuchoid body habits = tall stature and gynecomastia
• facial and body hair are sparse or absent
• mild intellectual disability
• gynecomastia
• long legs

Question 14

Marfan Syndrome

Answer 14

• arachnodactyly, scoliosis, aortic root dilatation

- due to an inherited defect of the ECM protein fibrillin

Question 15

Fragile X Mental Retardation

Answer 15

• Macroorchidism = enlarged testes
• large jaw and long face
• large Everett ears
• mitral valve prolapse, flat feet, and hypotonia
• intellectual disability

CGG repeat
X -linked = affects the methylation and expression of the FMR1 gene

Question 16

Turner Syndrome

Answer 16

45 XO

• short stature
• broad chest
• primary amenorrhea

Question 17

Bloom Syndrome

Answer 17

Premature aging due to shortened telomeres

Question 18

Telomerase

Answer 18

• reverse transcriptase (RNA-dependent DNA polymerase)

- lengthens telomeres by adding TTAGGG repeats to the 3’ end of chromosomes

Question 19

Insulin Biochemical Pathway

Answer 19

Anabolic hormone that acts via tyrosine kinase signaling to increase the synthesis of glycogen, proteins, fatty acids and nucleic acids
-Tyrosine kinase/phosphatidylinositol-3-kinase stimulation promotes glycogen synthesis by activating protein phosphatase, an enzyme that de phosphorylates (activates glycogen synthase)

Once pro insulin is made in the RER there is cleavage of pro insulin in the islet cell secretory granules that yields insulin and C-peptide which are stored in the granule until they are secreted in equimolar amounts

Question 20

What is tetrahydrobiopterin a cofactor for?

Answer 20

Tetrahydrobiopterin (BH4) is a cofactor in the synthesis of serotonin, tyrosine, and DOPA

Phenylalanine –> Tyrosine –> DOPA –>Melanin or Catecholamines

Tryptophan –> 5 hydroxytryptophan –>Serotonin

• serotonin is formed via hydroxylation and decarboxylation of tryptophan
• Phenylketonuria can result from BH4 deficiency due to Dihydropyridine reductase deficiency ===> serotonin deficiency and hyperphenylalanemia. Treatment = low phenylalanine diet and BH4 supplementation

Question 21

Ventricular Septal Defect

Answer 21

Low pitched holosystolic murmur heard best at the left sternal border with increase in hand grip

Question 22

Atrial Septal Defect

Answer 22

• mid-systolic pulmonary ejection murmur that results from increased flow across the pulmonic valve

Question 23

Aortic Regurgitation

Answer 23

Early diastolic murmur

Question 24

Genital Ulcer Disease

Answer 24

Check Pictures

Question 25

Mechanism of Action of Bacterial Toxins

Answer 25

Check Pictures

Question 26

Water Soluble Vitamins

Answer 26

See Pictures

Question 27

Coronary Steal Syndrome

Answer 27

- collateral micro vessels form adjacent pathways for blood flow to areas distal to an occluded vessel - Adenosine and dipyridamole are selective vasodilators of coronary vessels that can cause coronary steal = blood flow in ischemic areas is reduced due to arteriolar vasodilation in non ischemic areas because ischemic areas are already maximally vasodilated due to local vasodilators. Coronary steal can lead to hypoperfusion and worsening of existing ischemia

Question 28

Ehlers Danlos syndrome

Answer 28

- group of hereditary disorders characterized by defective collagen synthesis - caused by procollagen peptidase deficiency which causes impaired cleavage of terminal propeptides in the extra cellular space Clinical manifestation - joint laxity - hyper extensible skin - tissue fragility due to the formation of soluble collagen that does not properly cross link

Question 29

Uncomplicated umbilical Hernia

Answer 29

- defect at the linea covered by skin - caused incomplete closure of the umbilical ring which allows for protrusion of bowel through the abdominal musculature - most are reducible, asymptomatic, and resolve spontaneously in first few years of life - reducible bulge at the umbilicus notably with increased abdominal pressure Associated with Down syndrome, hypothyroidism, beck with-Wiedermann syndrome

Question 30

Oomphalocele vs. Gastrochisis

Answer 30

O = midline herniation of abdominal contents contained within a membranous sac G = full thickness abdominal wall defect that presents as intestines outside sac

Question 31

Pharyngeal Arches

Answer 31

``` First = trigeminal nerve and maxillary artery Second = facial nerve, muscles of facial expression, and stapedial artery Third = glossopharyngeal nerve, parts of the hyoid bone and stylopharyngeous muscle, common and proximal internal carotid arteries Fourth = superior laryngeal nerve of the vagus, muscles of the pharynx and soft palate, and some laryngeal muscles. Aortic arch and subclavian arteries Fifth = obliterated during fetal development Sixth = recurrent laryngeal nerves of the vagus, muscles of larynx, pulmonary arteries and ductus arteriosus ``` LOOK AT PICTURE

Question 32

Prolactin facts

Answer 32

- manufactured due to stimulation by TRH and is inhibited by progesterone Although prolactin secretion increases as pregnancy progresses, high progesterone levels inhibit lactation through negative feedback on prolactin on the anterior pituitary Lactation during pregnancy is suppressed due to high progesterone levels inhibiting the anterior pituitary

Question 33

Craniopharyngiomas

Answer 33

- supra stellar tumors found in children and composed of calcified cysts containing cholesterol crystals. They come from remnants of Rathke's punch an embryonic precursor of anterior pituitary

Question 34

Osteoporosis Facts

Answer 34

- African American women have higher bone density through out their lives than women of other ethnicities Non Modifiable risk factors - advanced age - female sex - white Hispanics or Asian ethnicity - personal or family history of fractures Modifiable Risk factors - decreased physical activity - Low BMI - poor calcium and vitamin D intake - excessive alcohol or tobacco use - premature menopause - glucocorticoid use

Question 35

Rheumatoid Arthritis Complication

Answer 35

Long standing rheumatoid arthritis can affect the cervical spine and cause vertebral malalignment that can affect the atlantoaxial joint - extension of the neck during endotracheal intubation can worsen the subluxation leading to acute compression of the spinal cord and vertebral arteries causing sudden areflexia of all extremities

Question 36

Intra ventricular Hemorrhage

Answer 36

- blood in the ventricles of the brain Common due to prematurity - Can be silent or present with altered level of consciousness, hypotonia, and decreased spontaneous movements - Symptoms: bulging anterior Fontanelle, hypotension, decrebrate posturing, tonic-clinic seizures, irregular respirations, and coma Usually originates from the germinal matrix Increased frequency with decreasing age and birth weight

Question 37

Clear Cell Carcinoma

Answer 37

Most common subtype of Renal Cell carcinoma - appears as cuboidal or polygonal cells with clear abundant cytoplasm and eccentric nuclei - golden yellow on microscope due to high glycogen and lipid content - originates from proximal renal tubules Risk factors include smoking and obesity Renal oncocytomas = collecting duct cells (with numerous mitochondria)

Question 38

Viral Myocarditis

Answer 38

Progressive onset of heart failure in the setting of a recent viral infection = dilated cardiomyopathy

Question 39

Filtration Fraction

Answer 39

FF = GFR/RPF

Question 40

Prokaryotic DNA polymerases

Answer 40

All 3 can remove mismatched nucleotides via their 3'-5' exonuclease activity Only DNA polymerase 1 has 5' to 3' exonuclease activity which is used to remove the RNA primer synthesized by RNA primase

Question 41

Transketolase

Answer 41

Converts Fructose 6 phosphate to a ribose sugar in the non-oxidative part of the HMP Shunt

Question 42

Phenylketonuria

Answer 42

Autosomal recessive defect of phenylalanine hydroxylase or BH4 (tetrahydrobiopterin) - Children present with intellectual disability, seizures, eczema, light haiir/skin, and a musty Odor Screening occurs 2-3 days after birth because the mother makes enzyme for fetus Maternal PKU = lack of proper dietary therapy during pregnancy = microcephaly, intellectual disability , growth retardation, congenital heart defects in child Treatment = restriction of phenylalanine intake and supplementation of tyrosine , must avoid artificial sweetener aspartame

Question 43

Anaplastic Tumor Characteristics

Answer 43

Cells that demonstrate a complete lack of differentiation - loss of cell polarity with complete disruption of normal tissue architecture, cells coalesce into sheets or islands in a disorganized fashion - significant variation in the shape and size = cellular and nuclear pleomorphism - Hyperchromatic nuclei with high N/C ratios - Giant multinucleated tumor cells

Question 44

Clinical Phenotypes of 21 Hydroxylase deficiency

Answer 44

CHECK PICTURES

Question 45

Common Causes of Myopathy

Answer 45

Check Pictures

Question 46

Cardiac Tissue Conduction Velocity

Answer 46

CHECK PICTURES

Question 47

Acute Inferior Wall MI

Answer 47

Right Ventricular Myocardial Infarction - presents with hypotension, elevated jugular pressure and clear lungs - leads 2,3, and AVF

Question 48

Amatoxins and Ricin

Answer 48

- from mushroom poisoning = Amanita phylloides or death cap - potent inhibitors of RNA polymerase 2 (halting mRNA synthesis) Ricin - from the castor oil plant Ricinus communis - potent toxin that inhibits protein synthesis by cleaving the rRNA component of the eukaryotic 60S subunit

Question 49

Lymphatic Drainage of the Leg

Answer 49

- superficial lymphatic system is divided into medial and lateral tracks Medial Track - runs up to the superficial inguinal lymph nodes bypassing the popliteal nodes - runs along the long sap heinous vein up the superficial inguinal lymph nodes and bypasses the popliteal nodes - lesion on medial = inguinal lymphadenopathy Lateral Track - drain the lateral part of the leg and communicates with the popliteal and inguinal nodes - lesions here = both popliteal and inguinal lymphadenopathy

Question 50

Cytomegalovirus

Answer 50

- causes mononucleosis-like syndrome - mono spot negative - in immunocompromised = primary or reactivated CMV infection can result in severe retinitis, pneumonia, esophagitis, colitis, or hepatitis

Question 51

Diabetes

Answer 51

Type 2 - excess visceral fat and limited subcutaneous fat - waist circumference & waist to hip ratio is very profound Type 1 - high ketone levels = DKA = no presence of insulin at all

Question 52

Differential Diagnosis of Vaginosis

Answer 52

Check Pictures Trichomonas = can be seen on wet mount Saline microscopy of vaginal discharge. Presents with yellow-green discharge and vaginal burning and is sexually transmitted

Question 53

Systemic Mastocytosis

Answer 53

- colonal mast cell proliferation occurs in the bone marrow, skin, and other organs - mast cell is associated with C-KIT receptor tyrosine kinase mutation - these cells have a large expression of tryptase - there is excessive histamine release from de granulation of the mast cells which causes syncope, flushing, hypotension, pruritus, and urticaria - histamine also induces gastric acid secretion which can lead to gastric ulcers - the excess acid inactivates pancreatic and intestinal enzyme causing diarrhea - other GI symptoms include nausea, vomiting, and abdominal cramps Overall causes Gastric hypersecretion

Question 54

Hepatitis E Virus

Answer 54

Unenveloped single stranded RNA virus that spreads through fecal oral route - cause high mortality in infected pregnant women

Question 55

Osteoporosis

Answer 55

- Trabecular thinning with fewer interconnections

Question 56

Osteitis Fibrosa Cystica

Answer 56

Skeletal Manifestation of Primary hyperparathyroidism - presents with bone pain - superiosteal erosions affecting the phalanges of the hand = affects mostly cortical (compact bone) - salt and pepper skull - brown tumor bone cysts

Question 57

Osteoporosis

Answer 57

Persistence of primary spongiosa said in the medullary cavity with no mature trabeculae - accumulation of woven bone and diffuse skeletal thickening

Question 58

Common Causes of Nonvalvular Heart Failure

Answer 58

Look at picture

Question 59

Diabetes

Answer 59

Type 2 - excess visceral fat and limited subcutaneous fat - waist circumference & waist to hip ratio is very profound Type 1 - high ketone levels = DKA = no presence of insulin at all

Question 60

Differential Diagnosis of Vaginosis

Answer 60

Check Pictures Trichomonas = can be seen on wet mount Saline microscopy of vaginal discharge. Presents with yellow-green discharge and vaginal burning and is sexually transmitted

Question 61

SIADH

Answer 61

- low plasma sodium and osmolality - concentrated urine - normal body fluid volume due to ANP - can be due to Small Cell lung cancer

Question 62

The -omas

Answer 62

VIPoma - diarrhea - hypokalemia - achlorhydria Glucagonoma Check Pictures Somatostatinoma - abdominal pain, gallbladder stones, constipation, hyperglycemia, and Steatorhea - inhibition of GI motility

Question 63

Superior Gluteal Nerve Lesion

Answer 63

- causes positive trandelenburg sign = hip drop observed contra lateral to lesion as the ipsilateral foot is lifted off the ground = superior gluteal nerve lesion or gluteus medius muscle - weakened gluteus medius can't contract - caused by injection at superiomedial quadrant of the left buttock (proper placement should be in superiolateral quadrant of left buttockor even better the anterograde real gluteal region) Injections to the superiomedial, inferomedial, and inferolateral regions of buttock risk injury to sciatic nerve Superior gluteal nerve gives innervation to gluteus medius and minimus = hip abductors inferior gluteal nerve = gluteus maximus = hip extender

Question 64

Supine Hypotensive Syndrome

Answer 64

CHECK PICTURES | - occurs a lot to pregnant women supine

Question 65

Types of Collagen

Answer 65

Type 1 = for mature scars LOOK AT PICTURE

Question 66

Hypertrophic Cardiomyopathy Pulse

Answer 66

A bifid carotid pulse with brisk upstroke (spike and dome)

Question 67

Central Vein Access via Femoral Vein

Answer 67

- the optimal site for obtaining vascular access in the lower extremity during cardiac catheterization is the common femoral artery below the inguinal ligament - if going above the inguinal ligament this can significantly increase the risk of retroperitoneal hemorrhage

Question 68

SHOCK

Answer 68

When it comes to hypovolemic shock - IV fluids that are normal saline are given to increase the intravascular and left ventricular end diastolic volumes. The increase in preload stretches the myocardium and increases end diastolic sarcomere length leading to an increase in stroke volume and cardiac output.

Question 69

Jervell and Lange-Nielsen Syndrome

Answer 69

Congenital Long QT syndrome - autosomal recessive - accompanied by congenital neuro sensory deafness

Question 70

How do you decrease mitral regurgitation?

Answer 70

By decreasing left ventricular afterload = will increase the forward to regurgitation volume ratio

Question 71

Sings of Reversible and Irreversible Injury

Answer 71

Reversible - myofibril relaxation = cardiac myocytes occurs with severe ischemia - dis aggregation of poly soles = ischemic injury - dis aggregation of nuclear granules - TAG accumulation - Glycogen loss Irreversible - Mitochondrial vacuoles action = involved mitochondria is permanently damaged and can't produce ATP

Question 72

IL-10

Answer 72

Important anti-inflammatory cytokine that inhibits TH1 cells and reduce expression of MHC2 and suppresses the activation of macrophages and dendritic cells

Question 73

Buerger's Disease (Thromboangiitis Obliteran's)

Answer 73

A vasculitis of medium and small sized arteries in the tibial and radial arteries - there is acute and chronic inflammation of the arterial walls often with thrombosis of the lumen which can undergo organization and recanalization - this segmental thrombosing vasculitis often extends into contiguous nerves and veins - this condition can result from direct endothelial cell toxicity from tobacco products or from hypersensitivity to it - usually seen among heavy cigarette smokers with onset before age 35 and is associated with hypersensitivity to intra dermal injections of tobacco extracts

Question 74

Drug Treatments for TB

Answer 74

See Pictures Mycolic acids in the cell wall cause mycobacteria to be acid fast as they retain the carbolfuschin dye and resist decoloration by acid-alcohol de colorizing agent

Question 75

Important GI Hormones & Impairments in Glycogenolysis

Answer 75

See Pictures

Question 76

Biotin Cofactors

Answer 76

See Pictures on

Question 77

Neurophysins

Answer 77

- carrier proteins for oxytocin and vasopressin (ADH) Act as chaperone molecules as they transport the hormones toward the nerve terminals in the posterior pituitary from their site of production in paraventricular and supraoptic nuclei Point mutations in neurophysin 2 = hypothalamic diabetes insipidus

Question 78

Phase 4 of SA node action potential

Answer 78

Acetylcholine and adenosine reduce the rate of depolarization by prolonging phase 4

Question 79

Valsalva Maneuver

Answer 79

- can induce vagal stimulation to decrease tachycardia - the rectus abdominus muscle is recruited in this process to achieve increased intra abdominal and intrathoracic pressure

Question 80

Gonorrhea

Answer 80

- can cause urethritis (dyslexia and purulent urethral discharge) - the nucleic acid amplification test is the diagnostic test of choice - intra cellular diplococci - dual therapy with ceftriaxone and azithromycin due to concerns about resistance and chlamydia co-infection

Question 81

Common Clinical Disinfectants

Answer 81

SEE PICTURE - formaldehyde and glutaraldehyde function by alkylation get and cross-linking DNA and proteins = most commonly used for sterilization of hospital instruments that cannot withstand autoclave temp

Question 82

Binding Globulins

Answer 82

An increase in estrogen activity increases levels of TBG this leads to an increase in total thyroid hormone levels, but feedback control maintains normal levels of free thyroid hormone - an increase in TBG leads to an increase in total T4 (bound T4 plus free T4) as well as total T3

Question 83

Gestational Trophoblastic Disease

Answer 83

See Picture Complete mole = snowstorm appearance

Question 84

Primary Biliary Cholangitis

Answer 84

- chronic autoimmune liver disease characterized by lymphocytic infiltrates and destruction of small and mid-sized intrahepatic bile ducts - common in middle aged women and is associated with other autoimmune disorders - serum alkaline phosphate is elevated and AMA titers are positive - granulomas and bile staining of hepatocytes are common

Question 85

Erythema multiforme

Answer 85

- cell mediated inflammatory disorder of the skin - erythematous papules that evolve into target lesions - most commonly associated with HSV

Question 86

DNA probes

Answer 86

- protein that must be able to bind DNA - transcription factors, steroids, thyroid proteins, vitamin D receptors, retinoic acid receptors, DNA transcription and replication proteins - N-myc and C-myc can bind DNA = transcription factors

Question 87

Toxic Megacolon

Answer 87

- well recognized complication of ulcerative colitis - patients typically present with abdominal pain/dissension, bloody diarrhea, fever, and signs of shock - use abdominal X-Ray - barium enema and colonoscopy are contraindicated due to risk of perforation

Question 88

Differential diagnosis and features of chest pain

Answer 88

See pictures

Question 89

Hypertensive disorders of pregnancy

Answer 89

See pictures

Question 90

Hemicholinium

Answer 90

Inhibits the sodium co-transporter bringing choline and sodium into the neuron. Inhibits production of acetylcholine. SEE PICTURE

Question 91

The Pharyngeal Pouch Derivatives

Answer 91

SEE PICTURES The floor of the foregut gives rise to the thyroid not the pharyngeal arches.

Question 92

Enterobius vermicularis (enterobiasis) PINWORM

Answer 92

Occurs more frequently in school age children - diagnosed by Scott tape test First line treatment = Albendazole and second line is pharyngeal pamoate

Question 93

What activates gaunylyl Cyclase?

Answer 93

ANP, BNPm NO

Question 94

Chronic AV shunt

Answer 94

- increases cardiac output because of SNS - decreases total peripheral resistance and increases venous return - causes the venous return curve to shift right because ECV is increased through renal retention of fluids and because venous pooling is reduced by the increases SNS tone

Question 95

Bones of Wrist and Hand

Answer 95

See Pictures Some Lovers Try Positions That They Can't Handle

Question 96

Nerve Distribution of the Leg

Answer 96

See Pictures

Question 97

Base Excision Repair and CaSr

Answer 97

See Picture CaSr = G-protein coupled receptors that regulate the secretion of parathyroid hormone in response to changes in circulating calcium levels.

Question 98

Central Retinal Artery Occlusion

Answer 98

Pale retina (due to ischemia and edema) and a cherry red macula - sudden, painless, and permanent, monocular blindness

Question 99

Trypsin Inactivation

Answer 99

See Pictures

Question 100

HLA proteins

Answer 100

Class 1 = HLA B27 - expressed by all nucleated cells Class 2 = HLA DR, DP, DQ - expressed by antigen presenting cells and present predominantly foreign antigens to CD4 helper T-cells - conditions associated with HLA class 2 include rheumatoid arthritis, diabetes type and celiac disease See Picture

Question 101

Primary Aldosteronism

Answer 101

See Pictures Disease prevalence = q^2

Question 102

For rare autosomal recessive disorders

Answer 102

2pq | P = 1

Question 103

Side Effects of Corticosteroids

Answer 103

See Picture - causes an increase in neutrophil count = demargination of neutrophils from their attachment on the vessel wall

Question 104

Type 2 Diabetes

Answer 104

Pancreatic Islet amyloid deposition is characteristic

Question 105

Ectopic Pregnancy

Answer 105

In an ectopic pregnancy the uterine specimen would reveal decidualized endometrium only - consisting with dilated coiled endometrial glands and vascularized edematous stroma These changes occur in the luteal phase of the menstrual cycle under the influence of progesterone as the endometrium prepares for implantation. Embryonic and trophoblastic tissue will be absent from the uterus

Question 106

Type 4 hypersensitivity reactions

Answer 106

Key cells involved are the macrophages, CD4 helper T cells and CD8 helper T cells - macrophages present the antigen to CD4 helper T cells - then the CD4 helper T cells secrete cytokines that recruit CD8 T cells to the area and produce the characteristic signs of induration and erythema

Question 107

Angioedema

Answer 107

Can be hereditary or acquired (ACE drugs) - in hereditary = low C1 esterase inhibitor activity leads to increases in bradykinin levels See Picture

Question 108

Hormone regulation

Answer 108

Permissiveness = when one hormone allows another to exerts its maximal effect - cortisol increases alpha 1 receptors on VSM to increase the effects of catecholamines Synergistic = when the combined effect of both drugs exceeds the sum of the individual drug effects Additive = when the combined effect of 2 drugs is equal to the sum of their individual effects Tachypylaxis = decreased drug responsiveness in a short period following one or more doses (rapidly developing tolerance)

Question 109

Drugs

Answer 109

Drug continuous infusion of a drug metabolized by first order kinetics, the steady state concentration is reached in 4-5 half lives.

Question 110

HIV

Answer 110

- in the HIV replication cycle - only the env gene polyprotein product is glycosylated to gp160 and is proteolytically cleaved within the endoplasmic reticulum and Golgi apparatus to form the envelope glycoproteins gp120 and gp41

Question 111

Types of Exocrine Glands

Answer 111

See Pictures

Question 112

Bloom Syndrome

Answer 112

- autosomal recessive - mutations in the BLM gene encoding helicase - Patients present with growth retardation, facial anomalies, photosensitive skin rash, and immunodeficiency due to chromosomal instability and breakage

Question 113

Patella Fractures

Answer 113

- due to a direct blow to the anterior aspect of the knee - the patella can also be fractured indirectly due to excessive force transmitted through the quadriceps tendon - patients develop acute swelling, tenderness, inability to extend the knee against gravity, and a palpable gap in the extensor mechanism

Question 114

Mood Stabilizers in Bipolar Disorder & Antifungal Targets

Answer 114

Check Pictures

Question 115

Biventricular Pacemakers

Answer 115

Has 3 leads - first 2 are placed in the right atrium and right ventricle - the third lead is used to pace the left ventricle and courses through the coronary sinus and resides in the anterioventricular groove in the posterior aspect of the heart

Question 116

Elastin Production

Answer 116

- synthesized as a large polypeptide precursor composed of about 700 mostly no polar amino acids - elastin contains proline and lysine residues but a few of these amino acids are hydroxylated - after trophoblastic is formed it is secreted in the Extracellular space where it interacts with fibrillin that functions a scafold - Then Lysil oxidase (requires copper) oxidatively delaminates some of the lysine residues of tropoelastin helping with the formation of desmosomes cross-links between neighboring polypeptides - these cross links allow for the rubber like properties of elastin The rubber like properties of elastin are due extensively cross-linking between elastin monomers, which is facilitated by Lysyl oxidase

Question 117

Lead Time bias

Answer 117

- an artificial increase in survival time among tested patients who actually have an unchanged prognosis - patients screened with more sensitive tests appear to live longer only because the disease was detected earlier than it would have been if diagnosed clinically - the overall length of tie from disease onset to death actually remains the same in both groups

Question 118

Beta blockers

Answer 118

- decrease AV nodal conduction | - leading to an increased AV nodal refractory period = PR interval prolongation

Question 119

Cromolyn

Answer 119

And Nedocromil | - inhibit mast cell degranulation and prevent release of preformed chemical mediators

Question 120

C. Diphtheria

Answer 120

The bacterium produces intra cellular poly phosphate granules that are called metachromic granules that can be detected on microscopy after methylene blue staining

Question 121

Giardia Lambilia

Answer 121

- cause injury to the duodenal and jejunal mucosa by adhering to the intestinal brush border and releasing molecules that induce a mucosal inflammatory response - Secretory IgA which impairs adherence is the major component of adaptive immunity against G. Lamblia FYI Eosinophils are used against worm infections only!

Question 122

HIV

Answer 122

- the high mutability for the evasion of host humoral and cellular immune responses and the development of resistance to anti-retrovirus drugs - Pol gene mutations are responsible for acquired resistance to HIV reverse transcriptase inhibitors and HIV protease inhibitors - Env gene mutations enable escape from host neutralizing antibodies

Question 123

Chest X Ray for Emphysema

Answer 123

Flattened Diaphragm!!!!

Question 124

Cystic Fibrosis

Answer 124

Look at Pictures - autosomal recessive disease that results from a mutation in the CFTR gene on chromosome 7 - The CFTR protein is a transmembrane ATP-gated channel

Question 128

Acute Respiratory Distress Syndrome

Answer 128

Pg 613 Remember white out of lungs and thick hyaline membranes - due to damage of type 1 pneumocytes

Question 129

Restrictive Lung Diseases

Answer 129

Pg 611-612

Question 130

Nephrogenic DI

Answer 130

Treated with Thiazides or indomethacin (to decrease synthesis of prostaglandins which inhibit ADH)

Question 131

Interstitial Lung Disease

Answer 131

- associated with decreased lung volumes and increased lung elastic recoil caused by fibrotic interstitial tissue. - the increased elastic recoil results in increased radial traction (outward pulling) on the airways leading to increased expiration flow rates when corrected for the low lung volume (opposite for emphysema)

Question 132

Intestinal atresia

Answer 132

See picture | - in the jejunum/ileum are due to vascular injury

Question 133

Bordatella Pertussis

Answer 133

- causes whooping cough - clinical presentation is a paroxysmal cough lasting >2 weeks that is associated with post-tussive eyes is or inspiratory whoop after a severe coughing episode SEE PICTURE

Question 134

Mitochondrial DNA

Answer 134

- exists as a small circular chromosome - codes for the rRNA and tRNA needed for mitochondrial protein synthesis - each mitochondria contains 1-10 copies of maternally derived mtDNA - mitochondria have a double membrane and wavy cristae - it resembles prokaryotic DNA and is maternally derived

Question 135

Left Renal Vein

Answer 135

- can be compressed by superior mesenteric artery

Question 136

Pathogens responsible for secondary bacterial pneumonia after a viral infection

Answer 136

- S. Pneumonia - S. Aureus - H. Influenza

Question 137

Psoriasis

Answer 137

- Can cause deforming joint disease | - common complications include arthritis, nail pitting, and uveitis

Question 138

AV shunts

Answer 138

- increase cardiac preload by increasing the rate and volume of blood flow back to the heart - because they bypass the arterioles, the TPR is reduced which decreases the after load as well - AV fistula is an abnormal communication between an artery and a vein that bypasses the arterioles the major source of resistance in the vascular system = can reveal a pulsatile mass with a thrill on palpating over the site or a constant bruit

Question 139

Rabies

Answer 139

- bats are main source of rabies - agitation and spasms progressing to coma with weeks of exposure is strongly supportive of rabies encephalitis - prophylactc vaccination is given for high risk people = inactivated vaccine

Question 140

Recurrences of genital herpes

Answer 140

- can be reduced through daily treatment with oral valacyclovir, acyclovir, or farcical over - condom use can help prevent a primary genital HSV infection but dose not prevent deactivation of latent infection

Question 141

Polycythemia

Answer 141

- defined as a hematocrit level >52% in men and >48% in women - it may be the result of a true increase in the red blood cell mass (absolute erythrocytosis) or decrease in the plasma volume (relative erythrocytosis)

Question 142

Carotid Sinus

Answer 142

- dilation of the internal carotid artery located just above the bifurcation of the common carotid artery - the carotid sinus reflex has an afferent limb that arises from the baroreceptors in the carotid sinus and travels to the vagal nucleus and medullary centers via the glossopharyngeal nerve - the efferent limb carries parasympathetic impulses via the vagus nerve

Question 143

To protect the thyroid from a nuclear accident

Answer 143

KI is given prophylactically to protect the thyroid from excessive accumulation of radioactive Iodide

Question 144

Iron absorption

Answer 144

Occurs primarily in the duodenum and proximal jejunum - bypass of the small bowel segment by gastrojejunostomy results in iron deficiency anemia - malabsorption of vitamin B12, folate, and ADEK Vitamin C = distal small bowel active process - B6 = jejunum and ileum passive process Biotin and pantothenic acid = small and large intestine via sodium dependent transporter

Question 145

Thioamides

Answer 145

Methimazole and propylthiouracil - decrease the formation of thyroid hormones by inhibition of thyroid per oxidase that is responsible for both iodine organification and coupling of iodotyrosines - PTU also decreases the peripheral conversion of T4-T3

Question 146

Treating Thromboembolisms in Pregnant women

Answer 146

- use low molecular weight heparin = enoxaprin (doesn't cross the placenta like warfarin)

Question 147

Veranicline

Answer 147

- partial agonist at the alpha4beta2 nicotinic acetylcholine receptor that reinforces the effects of nicotine in the CNS system - this drug competes with nicotine and prevents its binding - because it's a partial agonist it helps reduce the symptoms of nicotine withdrawal by mildly stimulating the receptor This drug assists patients with cessation of tobacco use by reducing withdrawal cravings and attenuating the rewards effects of nicotine

Question 148

Piriform Recess

Answer 148

- where food can get caught - a branch of the superior laryngeal vagus nerve is there which carries motor fibers to the muscles involved in vocal cord function - the nerve mediates the afferent limb of the cough reflex by carrying sensation from the mucosa superior to the vocal cords

Question 149

Henoch Schonlein purpura

Answer 149

- due to IgA immune complex Post-Glomerular Strep GN - granular deposition of IgG, IgM, and C3 in the mesangium and basement membrane - starry sky appeared - EM = sure epithelial humps

Question 150

Bethancol

Answer 150

Used for postoperative urinary retention | - muscarinic agonist that will allow for urination

Question 151

LaPlace's law

Answer 151

See Picture

Question 152

AV nodal Artery

Answer 152

- usually arises from the dominant coronary artery

Question 153

Erythropoeisis Stimulating Agents

Answer 153

- are used to treat anemia of chronic kidney disease - ESA's can improve anemia without need for blood transfusions There is a high risk thromboembolic events - due to increased blood viscosity as a result of the elevation in red cell mass - increased risk for hypertension due to activation of erythropoietin receptors on vascular endothelial and smooth muscle cells

Question 154

Green Color of pus and sputum from bacterial infections

Answer 154

- blue green heme based pigmented molecule contained within the azurophilic granules of neutrophils and catalyzes the production of hypochlorous acid (BLEACH) from chloride and H2O2 during the phagocytic respiratory burst ==> this is due to MYELOPEROXIDASE

Question 155

Influenza Vaccine

Answer 155

- inactivated killed vaccine = injection Function by inducing neutralizing antibodies against the hemagluttinin antigen in selected viral strains - Live attenuated vaccine = nasal spray Generate a strong cell mediated immune response in addition to providing humoral immunity

Question 156

Catalase Positive Organisms

Answer 156

- S. aureus - Burkholderia Cetacea - Serratia marcescens - Nocardia - Aspergillus

Question 157

Crohn's Disease

Answer 157

- due to a mutation in the NOD2 gene (expressed on epithelial cells and macrophages) - the gene activates the NF-kB pathway = this is a pro inflammatory transcription factor that increases cytokine production - In Crohn's disease mutations in NOD2 result in decreased activity of NF-kB pathway which impairs the innate immune response of the intestinal mucosa and allows intestinal microbes to induce an exaggerated response by the adaptive immune system, resulting in chronic GI inflammation

Question 158

Hepatic Abscesses

Answer 158

S. Aureus can cause this by hematogenous seeding of the liver Enteric bacteria (E. Coli, Klebsiella, and enterococcus) can cause hepatic abscesses by ascending the biliary tract (ascending cholangitis), portal vein premix, or direct invasion from an adjacent area

Question 159

FRC

Answer 159

- airway pressure equals zero | - but the intra pleural pressure is negative with a value of -5cm H20

Question 160

Structures derived from neural crest cells

Answer 160

``` Melanocytes Odontoblasts Tracheal cartilage Enterochromaffin cells Laryngeal cartilage Parafollicular cells of the thyroid Adrenal medulla Schwann cells Spiral membrane ``` MOTEL PASS

Question 161

Steroid Producing Cells

Answer 161

- cells in the adrenals, gonads, and liver

Question 162

Pyelonephritis

Answer 162

- suppression of endogenous flora, colonization of the distal urethra by pathogenic gram negative rods and attachment of these pathogens to the bladder mucosa are the stages of pathogenesis in the lower urinary tract infections - anatomical or functional vesicoureteral reflux is almost always necessary for the development of acute pyelonephritis

Question 163

Klinfelter Syndrone

Answer 163

- primary hypogonadism - elevated FSH and LH and low testosterone - long lower extremities, small, firm testes, and azoospermia

Question 164

Acute Tubular Necrosis

Answer 164

- due to decreased renal perfusion - straight proximal tubules and the thick ascending limb of Henle are the most commonly affected portions - muddy brown casts are seen

Question 165

Heparin and Warfarin

Answer 165

``` Heparin = PTT watch Warfarin = PT watch and also check INR ```

Question 166

Rebound Rhinorrhea

Answer 166

Topical preparations of alpha adrenergic agonists cause vasoconstriction of the nasal mucosa vessels and are used as decongestants - Overuse of these drugs cause negative feedback resulting in decreased norepinephrine synthesis and release from nerve endings which diminishes their effects

Question 167

Hemangioma

Answer 167

- never biopsy a hemangioma because it can lead to a fatal hemorrhage and has low diagnostic yield

Question 168

What is the earliest sign of diabetic nephropathy?

Answer 168

- moderately increased albuminuria is the earliest sign of diabetic nephropathy and the leading cause of ESRD - screening for early stage diabetic nephropathy is best achieved through the use of albumin urine dipsticks

Question 169

Sirloimus

Answer 169

- binds to the immunophilin FK-506 binding protein in the cytoplasm, this forms a complex that binds and inhibits mTOR - inhibition of mTOR signaling blocks IL2 signal transduction and prevents cell cycle progression and lymphocyte proliferation

Question 170

Artery the true pelvis

Answer 170

The ureter lies medial to the ovarian vessels and anterior to the internal iliac artery Increased intake of citrate and fluid help to prevent calculus formation 9,10,11 rib over lie the spleen 12th rib overlies the kidney

Question 171

Grape fruit Juice

Answer 171

- slows the breakdown of drugs by inhibiting the CYP450 ==> CYP3A enzymes

Question 172

Where does the most water reabsorption in occur in the nephron when there is 24 hours of water deprivation?

Answer 172

- The proximal tubules reabsorb >60% of the water filtered by the glomeruli, regardless of the patients hydration statu s

Question 173

Ethical obligations for impaired colleagues

Answer 173

- non emergency situation a person should contact the designated hospital committee, commonly called a physician health program - if this is not possible or such a body doesn't exist then the state licensing board should be contacted

Question 174

Linkage Disequilibrium

Answer 174

- a pair of alleles are inherited together in the same gamete more or less often than would be expected given random chance - this can occur even if the genes are on different chromosomes

Question 175

Pancreas

Answer 175

- the dorsal pancreatic bud = pancreatic tail, body, most of the head, and small accessory pancreatic duct - the ventral bud = uncinate process, pancreatic head and proximal portion of the main pancreatic duct

Question 176

Physicians and Gifts

Answer 176

- it is ethically problematic for physicians to accept expensive gifts as they may influence or appear to influence physician behavior - these gifts should be declined after expression of appreciation

Question 177

Osmotic Laxatives

Answer 177

Polyethylene glycol Magnesium Hydroxide Magnesium Citrate

Question 178

Chronic Lung Transplant Rejection

Answer 178

- affects the small bronchioli producing the obstructive lung disease known as bronchiolitis obliterans - characterized by lymphocytic inflammation, fibrosis, and ultimately destruction of the bronchioles

Question 179

What increases risk of statin myopathy?

Answer 179

- use with gemfibrozil = impairs the hepatic clearance of statins if given together

Question 180

Why does the myocardial cell swell during transient ischemia?

Answer 180

- ion pump failure due to ATP deficiency during cardiac ischemia causes intra cellular accumulation of Na+ and Ca2+ - this draws water into the cell causing the cellular and mitochondrial swelling

Question 181

Hypertrophic Cardiomyopathy

Answer 181

- produces a systolic murmur

Question 182

Contraindications for OCP use

Answer 182

- prior history of thromboembolic event or stroke - history of an estrogen-dependent tumor - women over age 35 years who smoke heavily - hypertriglyceridemia - decompensated or active liver disease - pregnancy

Question 183

Vasopressin and Desmopressin

Answer 183

- cause V2R mediated increase in water permeability in the cortical and medullary collecting ducts - vasopressin activates urea transporters in the medullary collecting duct, increasing urea reabsorption and decreasing renal urea clearance e - this increases the medullary osmotic gradient and allows for the production of maximally concentrated urine and

Question 184

Acute Cholecystitis

Answer 184

- caused by gallstones obstructing the cystic duct - the gallbladder will not be visualized due to the obstruction by a radio tracer - ultrasound findings = gallbladder wall thickening, pericholecystic fluid, and a + Murphy sign

Question 185

Cord Factor by Mycobacteria

Answer 185

- establishes virulence through neutrophil inhibition, - mitochondrial destruction - induced release of TNF

Question 186

Diffuse Esophageal Spasm

Answer 186

- several segments of the esophagus contract inappropriately at the same time which appears as disorganized non-peristaltic contractions on esophageal manometers and corkscrew esophagus on barium - pathogenesis = impaired inhibitory neurotransmission within the esophageal my enteric plexus

Question 187

Lymph Node drainage

Answer 187

Above the dentate line = inferior mesenteric and internal iliac lymph nodes Below the dentate line = inguinal nodes

Question 188

Mesothelioma

Answer 188

- dyspnea and chest pain - hemorrhagic pleural effusions are usually present - Nodular or smooth pleural thickening with the lung parenchyma intact - histopathology = tumor cells with numerous long slender micro villi and abundant toon filaments - use pancytokeratin as immunohistochemical marker

Question 189

Indicator of Obestity induced Restrictive Lung Disease

Answer 189

- reduction in expiratory reserve volume due to increased respiratory rates with reduced tidal volumes - obesity has minimal effect on residual volume but FRC is the sum of RV + ERV - so FRC is markedly decreased

Question 190

Ecthyma gangrenosum

Answer 190

- cutaneous necrotic disease with a strong association with Pseudomonas - occurs from peri vascular invasion and release of tissue-destructive exotoxins causing vascular destruction and insufficient blood flow to patches of skin that become edematous and necrosis - pseudomonas infections are common in patient that are neutropenia, hospitalized, have burns or indwelling catheters

Question 191

Acute Cholecystitis

Answer 191

- caused by gallstones obstructing the cystic duct - the gallbladder will not be visualized due to the obstruction by a radio tracer - ultrasound findings = gallbladder wall thickening, pericholecystic fluid, and a + Murphy sign

Question 192

Cord Factor by Mycobacteria

Answer 192

- establishes virulence through neutrophil inhibition, - mitochondrial destruction - induced release of TNF

Question 193

Diffuse Esophageal Spasm

Answer 193

- several segments of the esophagus contract inappropriately at the same time which appears as disorganized non-peristaltic contractions on esophageal manometers and corkscrew esophagus on barium - pathogenesis = impaired inhibitory neurotransmission within the esophageal my enteric plexus

Question 194

Lymph Node drainage

Answer 194

Above the dentate line = inferior mesenteric and internal iliac lymph nodes Below the dentate line = inguinal nodes

Question 195

Mesothelioma

Answer 195

- dyspnea and chest pain - hemorrhagic pleural effusions are usually present - Nodular or smooth pleural thickening with the lung parenchyma intact - histopathology = tumor cells with numerous long slender micro villi and abundant toon filaments - use pancytokeratin as immunohistochemical marker

Question 196

Indicator of Obestity induced Restrictive Lung Disease

Answer 196

- reduction in expiratory reserve volume due to increased respiratory rates with reduced tidal volumes - obesity has minimal effect on residual volume but FRC is the sum of RV + ERV - so FRC is markedly decreased

Question 197

Ecthyma gangrenosum

Answer 197

- cutaneous necrotic disease with a strong association with Pseudomonas - occurs from peri vascular invasion and release of tissue-destructive exotoxins causing vascular destruction and insufficient blood flow to patches of skin that become edematous and necrosis - pseudomonas infections are common in patient that are neutropenia, hospitalized, have burns or indwelling catheters

Question 198

Acute Cholecystitis

Answer 198

- caused by gallstones obstructing the cystic duct - the gallbladder will not be visualized due to the obstruction by a radio tracer - ultrasound findings = gallbladder wall thickening, pericholecystic fluid, and a + Murphy sign

Question 199

Cord Factor by Mycobacteria

Answer 199

- establishes virulence through neutrophil inhibition, - mitochondrial destruction - induced release of TNF

Question 200

Diffuse Esophageal Spasm

Answer 200

- several segments of the esophagus contract inappropriately at the same time which appears as disorganized non-peristaltic contractions on esophageal manometers and corkscrew esophagus on barium - pathogenesis = impaired inhibitory neurotransmission within the esophageal my enteric plexus

Question 201

Lymph Node drainage

Answer 201

Above the dentate line = inferior mesenteric and internal iliac lymph nodes Below the dentate line = inguinal nodes

Question 202

Mesothelioma

Answer 202

- dyspnea and chest pain - hemorrhagic pleural effusions are usually present - Nodular or smooth pleural thickening with the lung parenchyma intact - histopathology = tumor cells with numerous long slender micro villi and abundant toon filaments - use pancytokeratin as immunohistochemical marker

Question 203

Indicator of Obestity induced Restrictive Lung Disease

Answer 203

- reduction in expiratory reserve volume due to increased respiratory rates with reduced tidal volumes - obesity has minimal effect on residual volume but FRC is the sum of RV + ERV - so FRC is markedly decreased

Question 204

Ecthyma gangrenosum

Answer 204

- cutaneous necrotic disease with a strong association with Pseudomonas - occurs from peri vascular invasion and release of tissue-destructive exotoxins causing vascular destruction and insufficient blood flow to patches of skin that become edematous and necrosis - pseudomonas infections are common in patient that are neutropenia, hospitalized, have burns or indwelling catheters

Question 205

IL-2 Activity

Answer 205

- produced by Helper T cells and is the major growth factor for T lymphocytes - stimulates the growth, differentiation, and survival of antigen-specific CD4 T cells and CD8 T-cells - also promotes the growth of B cells and activates natural killer cells and monocytes - Increased activity of T cells and NK cells are thought to be responsible for IL-2's anti-tumor effects - IL-2 is currently used as immunotherapy for metastatic melanoma and renal cell carcinoma

Question 206

GERD histology finding

Answer 206

- basal Zone hyperplasia | - elongation of the lamina propria papillae and scattered eosinophils and neutrophils

Question 207

Inferior Wall of the Heart

Answer 207

- supplied by the right coronary artery | - lead 2,3, AVF

Question 208

Ecological Studies

Answer 208

- unit of analysis is populations and not individuals - the frequency of a given characteristic and a given outcome are studied using population data - useful for generating hypotheses but should not be used to make conclusions regarding individuals within these populations

Question 209

Other EBM things to know

Answer 209

- Nested case control designs = start with cohort studies in which participants are followed over time and those participants who develop an outcome of interest become cases for a case-control study - Qualitative Studies = use focused discussion groups, interviews, and other anthropological techniques to obtain narrative information that can be crucial in explaining quantitative results

Question 210

Bisphosphonate

Answer 210

- have a similar structure to pyrophosphate and attach to hydroxyapatite binding sites on bony surfaces preferentially binding in areas of increased bone turnover - induce osteoclast apoptosis

Question 211

CCB

Answer 211

- The SA and AV node undergo diastolic depolarization during phase 4 due to a slow, inward sodium current - verapamil slows the diastolic depolarization that occurs in phase 0 and the latter part of phase 4 = SA and AV node - in cardiac muscle cells it decreases the excitation and contraction coupling - pay attention to the CELL specified

Question 212

Bradykinin

Answer 212

- hormone produced by the kidney | - acts locally to constrict veins and dilate arterioles to increase renal perfusion

Question 213

Foscarnet

Answer 213

- pyrophosphate analog that is sometimes used for ganciclovir-resistant CMV infections - can chelate calcium - can cause renal hypomagnesemia and a reduction in the release of PTH which contributes to hypocalcemia - the hypocalcemia and hypomagnesemia promotes seizures

Question 214

Skull exits for the cranial nerves

Answer 214

Pg 475 Remember CN 5 mandibular exits through the foramen ovale CN 5 maxillary exits through foramen rotund up

Question 215

Ataxia Telangiectasias

Answer 215

- increased risk of sinopulmonary infections that constitute a characteristic triad of ataxia telangiectasia = cerebellar ataxia, Telangiectasias, and increased risk of sinopulmonary infections - talengiectasia - superficial blanching nests of distended capillaries on sun exposed areas of the skin - autosomal recessive inheritance - defect in gene that codes for ATM gene that plays a role in DNA break repair - the immune deficiency manifests as an IgA deficiency that predisposes to infections of the upper and lower airways

Question 216

Patients with HIV

Answer 216

- headaches, seizures, and multiple ring enhancing CNS lesions on MRI = toxoplasmosis encephalitis

Question 217

Horners Syndrome + Muscle weakness in ipsilateral arm

Answer 217

Think Pancoast tumors

Question 218

Spinal accessory nerve

Answer 218

- made of fibers from cranial and cervical spinal nerve roots - passes through the posterior triangle of the neck and provides innervation to the SCM and trapezius - lesion = impaired abduction of the arm above horizontal and drooping of the shoulder

Question 219

Polio vaccines

Answer 219

- The live attenuated Sabin vaccine produces a stronger mucosal secretory IgA immune response than the inactivated poliovirus vaccine

Question 220

Glossopharyngeal Nerve

Answer 220

- causes loss of sensation in the upper pharynx, posterior tongue, tonsils, and middle ear cavity, and loss of taste sensation of the posterior third of tongue

Question 221

Ethics

Answer 221

- Physicians are not required to provide medical services against their personal beliefs - once a patient physician relationship is made the physician can refer the patient to another provider who can perform the requested medical service - physicians should respond to disclosure of past sexual abuse with empathy and concern. Clearly acknowledging the trauma and communicating willingness to discuss it when the patient is ready

Question 222

Possible Triggers for Prinzmetal angina

Answer 222

- cigarette smoking - cocaine/amphetamines - dihydroergotamine/Triptans = constricts vascular smooth muscle via stimulation of both alpha-adrenergic and serotonergic receptors

Question 223

Heart Failure contributions

Answer 223

- RAAS activation and SNS activation results in increased after load, excessive fluid retention and deleterious cardiac remodeling

Question 224

Places most susceptible to atherosclerosis

Answer 224

- lower abdominal aorta and coronary arteries

Question 225

Candida

Answer 225

- Germ tubes at 37 degrees Celsius

Question 226

Calcium efflux from cardiac cells prior to relaxation

Answer 226

- mediated by the Na/Ca exchange pump and Sarcoplasmic reticulum Ca-ATPase pump

Question 227

Rifaximin

Answer 227

- nonabsorbable antibiotic that alters GI flora to decrease intestinal production and absorption of ammonia = decreases intra luminal ammonia production - lactulose = increases conversion of ammonia to ammonium

Question 228

Eosinophilic Damage

Answer 228

- major basic protein released by eosniophils normally functions to kill helminths - it is also though to contribute to the bronchial epithelial damage sustained by patients with atopic (extrinsic allergic asthma)

Question 229

Campylobacter

Answer 229

- can get from exposure to domestic animals (cattle, chickens, dogs) or contaminated food Vibrio parahemolyticus = transmitted by contaminated shellfish

Question 230

Exacerbation of myasthenia Travis

Answer 230

In a patient treated with long acting acetylcholinesterase inhibitors occurs due to myasthenic or cholinergic crisis - The edrophonium (tension) test helps to differentiate - Clinical improvement after the test indicates that the patient is under treated

Question 231

Prokaryotic DNA polymerase

Answer 231

DNA Poly 1 = has both 5'-->3 ' and 3-->5' exonuclease activity = which means it can remove the RNA primer created by RNA primate and repair damaged DNA sequences DNA Poly 3 = only has 3'-->5' activity

Question 232

Multi factorial Inheritance

Answer 232

- the complex interaction of numerous genetic and environmental factors to determine phenotypic expression - although the exact inheritance risk cannot be determined, the closer a relative is to the affected person, the more likely the relative is to develop the trait

Question 233

Group B S. Agalacticae treatment

Answer 233

- Universal prenatal screening for group B strep colonization by vaginal-rectal culture at 35-37 weeks gestation is recommended to identify colonized women who require intrapartum antibiotics, most frequently with penicillin or ampicillin to prevent neonatal GBS sepsis pneumonia and meningitis Don't give penicillin earlier than 35 weeks because it will clear from the females system and can still come back again before delivery

Question 234

Spread of different Bacteria

Answer 234

N. Meningitidis --> Pharynx -> blood -> choroid plexus -> meninges H. influenza --> Pharynx -> lymphatics -> meninges M. Tuberculosis --> primary lung focus --> blood --> meninges

Question 235

Statins

Answer 235

- when it comes to Statins = hepatotoxicty is more of a fear than muscle - so check LFT's first before checking serum creatinine (for renal failure)

Question 236

COPD and Fibrosis

Answer 236

The work of breathing is minimized in patients with increased elastic resistance when their respiratory rate is high and tidal volume is low - patients with diseases that increase airflow resistance breathe at a lower rate/higher tidal volume in order to minimize the work of breathing

Question 237

What drug helps with hair growth?

Answer 237

Finestaride

Question 238

Dopamine Hydroxylase Deficiency

Answer 238

- causes dysautonomia which is ptosis, orthostatic hypotension, hypoglycemia, and hypothermia

Question 239

Bacillus Anthracis

Answer 239

- found in soil and able to survive past the boiling point of water At 100 - spore forming bacteria are able to survive high temperatures, desiccation, and chemical agents by forming spores - Spore forming bacteria can be killed by autoclave

Question 240

Atropine

Answer 240

- reverses the muscarinic symptoms of organophosphate poisoning but has no nicotinic effects - so patients treated with atropine are still at risk of muscle paralysis

Question 241

Alpha-1 antitrypsin

Answer 241

- associated with reddish-pink, periodic acid-Schiff positive granules of un-secreted polymerized AAT in the peri portal hepatocyte

Question 242

Frontal Lobe lesions

Answer 242

- Left sided lesions = are associated with apathy and depression - Rightsided lesions - disinhibition of behavior

Question 243

Ureter blood supply

Answer 243

- proximal ureter to the kidney = renal artery - distal ureter close to the bladder = superior vesical artery - circulation to the middle portions are highly variable Fat emboli in the pulmonary vasculature stain black with osmium tetroxide

Question 244

TCA

Answer 244

-have anti muscarinic side effects = confusion, constipation, and urinary retention Amityrptiline

Question 245

Long Half life's of Benzodiazepene

Answer 245

- chlordiazepoxide - diazepam - flurazepam Intermediate half life = Alprazolam and Clonazepam Short half life = Triazolam Benzos that are preferred in patients with impaired hepatic metabolism that undergo glucoronidation directly and are not dependent on hepatic enzymes = Lorazepam, oxazepam, temazepam

Question 246

Parkinson's Disease On-Off phenomenon

Answer 246

- thought to be a consequence of progressive nigrostriatal neurodegeneration leading to a decreased therapeutic window for levodopa - unpredictable - this phenomenon does not resolve

Question 247

Bilateral Anterior Cerebral Artery Occlusion

Answer 247

- behavioral symptoms (Abulia) | - urinary incontinence = micturition center = medial frontal lobe/cingulate gurus

Question 248

Atropine

Answer 248

- can cause acute closed angle glaucoma by narrowing of the anterior chamber angle and diminished outflow of aqueous humor

Question 249

First line treatment for essential tremor

Answer 249

- nonspecific Beta adrenergic antagonist

Question 250

Myotonic Dystrophy

Answer 250

- autosomal dominant disorder - increased number of trinucleotide repeats on myotonia proteins kinase gene - sustained muscle contraction, along with weakness and atrophy - cataracts are seen in almost all patients - frontal balding and gonadal atrophy are other common features

Question 251

Increasing Diffusion Rate

Answer 251

- increased with temperature due to increased molecular movement speed and increased macromolecule solubility - larger membrane surface areas - increased solubility of the diffusing substance

Question 252

Neprilysin

Answer 252

- a metalloprotease that cleaves and I activates endogenous peptides including natriuretic peptides glucagon, oxytocin, and bradykinin

Question 253

Herpesvirus Family

Answer 253

- the herpesvirus family bud through and acquire the lipid bilateral envelope from the host cell nuclear membrane - But overall most enveloped nucleocapsid viruses acquire their lipid bilateral envelope by budding through the plasma membrane of the host cell

Question 254

Nitrates

Answer 254

- patients taking daily maintenance nitrates need to have a nitrate free period every day to avoid tolerance to the drug

Question 255

Delirium

Answer 255

- may manifest as acute changes in cognition and behavior - low dose antipsychotics (haloperidol) are the medications of choice to treat the behavioral and psychotic manifestations of delirium - do not give benzo's because it can worsen the state unless it is in the case of alcohol withdrawal

Question 256

Anti-Arrhythmics

Answer 256

Use dependence describes the phenomenon in which higher rates of depolarization leads to increased sodium channel blockade due to the channels spending less time in the rating state - For Class 1 = sodium channel binding strength is 1C>1A>1B - class 1C demonstrates the most use dependence and class 1B has the least

Question 257

Bilateral Renal Artery Stenosis

Answer 257

- GFR is dependent on Angiotensin 2 mediated efferent arteriolar vasoconstriction in RAS - ACE inhibitors or A2 receptor inhibitors will cause efferent arteriolar vasodilation that causes the GFR to fall and may lead to the development of acute renal failure

Question 258

Features that Aid in Localizing a Transverse Spinal Cord

Answer 258

- moving roster ally spinal levels have increasing amounts of white matter, decreasing amount of gray matter and are more oval shaped - lower cervical and limbo sacral regions have larger ventral horns because they innervated the limbs - Thoracic and early lumbar sections contain lateral gray matter horns - Gracile and cuneate fasiculiare present above the T7 spinal level, whereas only the gracile Fasciculus is present below this level.

Question 259

Meningitis

Answer 259

- their outer membrane LOS is the same as LPS and it accounts for the morbidity and mortality in infected people

Question 260

Rat Poison

Answer 260

- Same thing as warfarin - to treat an overdose very quickly you must give fresh frozen plasma and also vitamin K - FYI heparin overdose is treated with protamine sulfate

Question 261

H. Influenza

Answer 261

- blood loving organism that gets its NAD+ from co-culture with S. Aureus and demonstrates the satellite phenomenon

Question 262

K+ sparing diuretics

Answer 262

- work on the collecting duct = Late distal tubule and cortical collecting duct

Question 263

Spontaneous intracranial hemorrhage

Answer 263

- most common cause in young adults are AV malformations, ruptured cerebral aneurysms, or sympathomimetic drugs like cocaine - this can also occur due to coarctation of the aorta causing high pressures in the brain

Question 264

Insulin Types

Answer 264

- Short acting insulin = best for post-meal hyperglycemia - Regular insulin = best for DKA - NPH = is given twice a day - long acting insulin analogs = are best for basal levels

Question 265

Renal Facts

Answer 265

- Drug induced tubular necrosis = aminoglycosides, radio contrast media, cisplatin, amphotericin B, and foscarnet - Drug induced tubular obstruction may be due to intra tubular precipitation of tissue degradation products drugs, or drug metabolites ==> sulfonamides, methotrexate, IV acyclovir, and triamterene = can precipitate in renal tubules and cause renal failure - Acute allergic interstitial nephritis = methicillin, cephalosporins, Acetozolamide, allopurinol, sulfonamides, and NSAIDs - Chronic allergic interstitial nephritis = lithium and cyclosporine ACE inhibitors can be bad by precipitating acute renal failure in those that have atherosclerotic disease and are dependent on efferent arterioles constriction to maintain renal perfusion (renal artery stenosis)

Question 266

Subarachnoid Hemorrhage

Answer 266

- patients that survive the initial subarachnoid hemorrhage can have a number of complications - some may develop secondary arterial vasospasm = this vasospasm occurs in the vessels surrounding the ruptured aneurysm - the secondary vasospasm causes cerebral ischemia which presents as new-onset confusion and focal neurological deficit - severe vasospasm 4-12 days after the initial insult is the major cause of morbidity and mortality in patients recovering from SAH Rebleeding can also occur - symptoms include the sudden development of a severe headache, severe nausea and vomiting, a change in the level of consciousness and the appearance of new neurological deficits - if rebleeding occurs the CT scan can identify the newly extravasated blood

Question 267

Toxic Shock Syndrome

Answer 267

- S. Aureus creates superantigen that activates large numbers of helper T cells - super antigens interact with major histocompatibility complex molecules on antigen presenting cells and T cell raptors to cause a widespread activation of T lymphocytes - activation of T cells is responsible for the release of IL2 from the T cells and IL-1 and TNF from macrophages - these IL's cause capillary leakage, circulatory collapse, hypotension, shock, fever, skin findings, and multi organ failure

Question 268

Antipsychotic Side Effects

Answer 268

Extra pyramidal - Acute dystonic reaction = sudden onset of sustained muscle contractions - Akithisia = subjective restlessness with inability to sit still or stand in one position - Drug induced Parkinsonism = tremor, rigidity, bradykinesia, masked facies Tardive Dyskinesia - involuntary movements after chronic use (ex: lip smacking, choreoathetoid movements) - this is the only side effect that can worsen or persist following medication discontinuation Neuroleptic malignant syndrome - Fever, rigidity, mental status changes, autonomic instability

Question 269

Lung Transplantation

Answer 269

Acute rejection = pulmonary and bronchial vessels are targets Chronic rejection = small airways are affected causing bronchiolitis obliterans (inflammation and fibrosis of the bronchiolitis walls lead to narrowing and obstruction of the affected bronchioli)

Question 270

Important

Answer 270

Cancers of the pelvis including the prostate spread to the lumbosacral spine via the vertebral venous plexus = this is why the brain is the first metastasis site when it comes to prostate cancer

Question 271

Respiratory acidosis

Answer 271

Acute = heroin overdose that causes Hypoventilation Chronic = COPD allows enough time for renal compensation

Question 272

Trigeminal Neuralgia

Answer 272

- Carbamezapine is the drug of choice | - Baclofen and Valproic acid are second line

Question 273

The main cause of overdose death

Answer 273

Opioids = #1 Heroin = #2 Prescription Analgesics = #3

Question 274

Pericarditis

Answer 274

Acute due to viral infection = friction rub Constrictive pericarditis = kussmaul breathing and pericardial knock - requires months or years to develop

Question 275

LPS

Answer 275

In gram negative species is a very long heat stable molecule arranges into three regions O antigen = cell wall outer membrane polysaccharide antigen used to classify gram negative bacteria Core polysaccharide Lipid A = responsible for the toxic properties of LPS that lead to gram negative sepsis and endotoxins septic shock. Causes widespread activation of macrophages leading to the widespread release of IL-1 and TNF-alpha LPS is not actively secreted by bacteria

Question 276

Tamoxifen

Answer 276

A selective estrogen receptor modulator used in the treatment of estrogen receptor positive breast cancer - it is a prodrug metabolized by CYP2D to its active metabolite endoxifen - patients with genetic polymorphism a resulting in poor CYP2D activity are exposed to decreased levels of the active metabolite and have a higher risk of disease relapse

Question 277

Treatment for Transient Ischemic Attack

Answer 277

- blood pressure control - statin - low dose aspirin which selectively inhibits COX1 and can increase risk of GI bleeding

Question 278

Nitric Oxide

Answer 278

Is found in the cortex, hippocampus, hypothalamus, cerebellum and olfactory system and is thought to participate in the formation of new memories - it is a unique neurotransmitter because it freely diffuses across cell membranes and does not need to interact with other neurons via a synapse

Question 279

Heart Failure cells

Answer 279

Hemosidierin macrophages - macrophages containing golden cytoplasmic granules that turn dark blue with Prussian blue staining - this means left ventricular dysfunction - macrophages eat the red blood cells that come into the blood

Question 280

Choleliathisis in Pregnancy

Answer 280

- Pregnancy and the usage of OCP's predispose to gallstone formation - Estrogen increases cholesterol synthesis by up regulating HMG-CoA reductase which causes the bile to become supersaturated with cholesterol - Progesterone reduces bile acid secretion and slows gallbladder emptying Gallstones are increased in women that are fat, fertile, female, and forty

Question 281

Bacterioides Fragilis

Answer 281

- apart of the normal colonic flora | - can form abscesses within the GI tract

Question 282

Pudendal nerve Block

Answer 282

- performed by injecting an anesthetic intravaginally - medial to the ischial spine and through the sacrospinous ligament - this provides anesthesia to most of the perineum

Question 283

Lyme disease in pregnant women

Answer 283

- Ammoxicillin should be given instead of Doxycycline due to teratogenic effects

Question 284

Important

Answer 284

- Never give a patient both an SSRI and a MAO inhibitor - this is due to the risk of serotonin syndrome This is why Patients must wait at least 2 weeks after MAO inhibitor discontinuation before initiating SSRI therapy allowing enough to time for regeneration of MAO

Question 285

Cleft Lip and Cleft Palate

Answer 285

Cleft Lip = maxillary prominence fails to fuse with the intermaxillary segment during the 5th-6th week of development Cleft Palate = palatine shelves fail to fuse with one another or with the primary palate. Cleft lit and palate can occur together or in isolation

Question 286

Protein Structue

Answer 286

Primary = covalent peptide bonds Secondary = alpha helix or beta sheet with hydrogen bonding Tertiary structure = overall shape a single polypeptide chain makes after compaction from secondary structure (ionic bonds, hydrophobic interactions, hydrogen bonds, and disulfide bonds

Question 287

Liver Can't use Ketone bodies

Answer 287

- Lacks the succinyl CoA transferase enzyme (thiophorase) to convert the ketone body to acetoacetyl CoA

Question 288

S. Pyogenes

Answer 288

- Pyrrolidonyl arylamidase positive

Question 289

Neutropenic Patients

Answer 289

- are at high risk for viral and fungal infections - the most common fungal causes are Aspergillus and candida species - invasive pulmonary aspergillosis presents with some combo of fever, chest pain, cough, dyspnea, and hemoptysis

Question 290

Important

Answer 290

Changes in host range are most commonly caused by a mutation in the viral encoded surface glycoproteins that mediates virion attachment to targets host cell plasmalemma receptors

Question 291

Nicotinic Receptors

Answer 291

- a type of inotropic receptor that doesn't depend on 2nd messenger - these receptors are ion channels that are comprised of 5 subunits with 2 ACh binding sites. - if and only if both binding sites are filed, the ion channel will open

Question 292

If a person is infected with Hep B

Answer 292

- and they have acute hepatitis with mild or sub clinical symptoms - they will eventually completely resolve 3 types of Hep B infections - acute hepatitis with complete resolution (>95 of cases) - fulminant hepatitis with massive liver necrosis - chronic hepatitis with or without cirrhosis

Question 293

Normal Aging in the Heart

Answer 293

- include a decrease in left ventricular chamber apex to base dimension - development of a sigmoid shaped ventricular septum - myocardial atrophy with increased collagen deposition - accumulation of cytoplasmic lipofuscin pigment within cardiomyocytes

Question 294

Candida Infection

Answer 294

- Local defense = superficial infection is by T lymphocytes | - hematogenous defense for disseminated candidiasis = neutrophils

Question 295

Kozak Sequence

Answer 295

- occurs on eukaryotic mRNA and is defined by gccRccAUGG in which R is either adenine or guanine. This sequence helps initiate translation at the methionine start codon.

Question 296

Bleeding in Pateints kidney disease (Uremia)

Answer 296

Renal failure - the accumulation of uremic toxins in the circulation impair platelet aggregation and adhesion resulting in a qualitative platelet disorder that only prolongs bleeding time - Uremic bleeding can be improved with dialysis because it removes the toxins and partially reverses the bleeding abnormality

Question 297

Acute Chest Syndrome

Answer 297

Occurs in sickle cell patients - due to vaso-occlusive crisis localized to the pulmonary vasculature -

Question 298

Inflammatory Leukocyte Accumulation Steps

Answer 298

1. Margination = increased vascular leakage in the micro vasculature leads to hemoconcentration and decreased wall shear stress, improving the contact of neutrophils with the endothelial lining 2. Rolling = Neutrophils roll on the endothelium via the loose binding of sialylated carbohydrate groups to L-selectin on neutrophils or E-selecting/P-selection on endothelial cells. Cytokine stimulation increases expression of endothelial selectins 3. Activation: slow rolling allows the leukocyte to sample the chemokines secreted by the inflamed tissue. This activates the integrins by inducing a signaling cascade that results in a conformational change in the integrins necessary for binding 4. Tight adhesion and crawling: neutrophils become firmly attached to the endothelium via the binding of CD18 beta 2 integrins (Mac-1 and LFA1) to intercellular adhesion molecule 1 (ICAM-1) on endothelial cells 5. Transmigration: after crawling to the endothelial cell periphery, neutrophils eventually migrate out of the vasculature by squeezing in between the cells via integrin attachments and adherence to platelet endothelial cell adhesion molecule 1 (PECAM-1). This protein is found primarily at the peripheral intercellular junctions of endothelial cells.

Question 299

Dermatomyositis

Answer 299

- proximal muscle weakness - heliotrope rash in the perioorbital area and cheeks along with got rods papules on the hands - has a strong association with malignancy (lung, colorectal, and ovarian cancer)

Question 300

Theophylline Intoxication

Answer 300

- Seizures are the major cause of morbidity and mortality - Tachyarrhythmias are the major concern but do not usually cause QT prolongation Treatment of theophylline intoxication includes administration of activated charcoal to reduce GI absorption. Beta blockers are the drug of choice for theophylline induced Tachyarrhythmias Seizures can be treat with benzo and barbituates

Question 301

SAH

Answer 301

Sub arachnoid hemorrhage has a risk of vasospasm due to blood breakdown (4-10 days after hemorrhage) = giving a patient a CCB can help in preventing these symptoms

Question 302

Penicillins

Answer 302

Inhibit transpeptidases by binding covalently to their active site

Question 303

Acute Compartment Syndrome

Answer 303

Most common in the anterior compartment of the leg = includes the foot extensor muscles, anterior tibial artery, and the deep peroneal (fibular) nerve - Injury to the deep peroneal nerve causes decreased sensation between the first and second toes, decreased dorsiflexion of the foot, foot drop, and claw foot

Question 304

Health Risk Assessment

Answer 304

A questionnaire that uses demographic, medical, lifestyle, and family history information to calculate a patients risk age. - A patient whose risk age is greater than chronological age has a higher risk of death than the average individual of that chronological age

Question 305

Antioxidants

Answer 305

Superoxide dismutase in as an antioxidant that neutralizes reactive oxygen species, preventing cell injury

Question 306

Placement of a Tracheal Tube

Answer 306

Between the superficial cervical fascia and cricothyroid membrane It goes through the following structures 1. Skin 2. Superficial Cervical Fascia (including subcutaneous fat and platysma muscle) 3. Investing and pre tracheal layers of the deep cervical fascia 4. Cricothyroid membrane

Question 307

Capitation

Answer 307

An arrangement in which a payor (individual, employer, or government entity) pays a fixed determined fee to cover all medical services required by a patient - payment structure in HMO's - the payor can directly negotiate a capitated contract with an insurance company that then pays the providers, or a large medical group may negotiate directly with the payor

Question 308

Lithium Toxicity

Answer 308

Can occur from thiazides, NSAIDs, or ACE inhbitors

Question 309

Differentiating Between DIC and TTP

Answer 309

- both have schistocytes - in DIC everything will be increased including PT, PTT, and BT - in TTP only Bleeding Time will be increased

Question 310

Transference

Answer 310

- unconscious shifting of emotions or desires associated with a person from the past to another person in the present

Question 311

Cystathione Deficiency

Answer 311

Can present as marfinoid habits due to homocystinuria = supplement B6 in diet Affected people have marfinoid habitus, ectopia lentis, and development delay. High risk of thromboembolism

Question 312

Opening Snap of Mitral Stenosis

Answer 312

- will get worse when A2 and OS gets closer together | - this tells you that the pressures in the left atria are very high

Question 313

Emetic Center of the Brain

Answer 313

Area Postrema | - lies in the dorsal medulla near the fourth ventricle

Question 314

Recombination vs. Reassortment

Answer 314

Recombination = exchange of genes between 2 chromosomes via crossing over within homologous regions. The resulting proveny will have recombined genomes with traits not present simultaneously in either parent virus = nonsegmented virus = 2 dsDNA strands Reassortment = genetic composition that occurs when host cells are coinfected with 2 segmented viruses that exchange whole genome segments. (I.e. Influenza)

Question 315

Propofol and other highly lipophilic drugs

Answer 315

- readily diffuse across membranes quickly accumulating in tissues receiving high blood flow, this accounts for their rapid onset of action. - these compounds are then distributed to organs receiving less blood flow, which explains their short duration of action

Question 316

Ganciclovir Therapy

Answer 316

- neutropenia is a significant adverse effect and is increased with co-administration of zidovudine or TMP-SMX

Question 317

Graves Disease Exopthalmos

Answer 317

High dose glucocorticoids like prednisone are used to control severe Grave's opthalmopathy - they are helpful in decreasing the severity of inflammation and decreasing extra ocular volume = Conventional anti thyroid drugs do not improve this

Question 318

Acyclovir

Answer 318

- can cause crystalline nephropathy if adequate hydration is not provided

Question 319

How to avoid wrong site surgery?

Answer 319

- Mark the operative site - independent verification of the patient, procedure, and site by 2 health care workers (nurse and physician) should be performed - the dual identifiers must perform the verification independently because 2 clinicians verifying identifiers together can result in replicating an error - surgical timeout before the procedure in order to conduct a final verification of the patient, procedure and site

Question 320

Important

Answer 320

When atherosclerotic occlusion develop slowly over time there can be compensation by the development of arterial collateral around the point of occlusion - the collateral circulation can provide flow to the hypoperfused areas distal to the point of occlusion Thin fibrous cap and increased lipid core and active inflammation = more likely to rupture

Question 321

Lipofuscin

Answer 321

Yellow brown finely granular perinuclear pigment = produce of free radical injury and lipid peroxidation = aging

Question 322

Tuberculosis

Answer 322

Active TB is never treated with drug mono therapy due to the fast emergence of mycobacterial antibiotic resistance from rapid, selective gene mutations - Isoniazid mono therapy may be used for patients who have a positive PPD and a negative chest X Ray

Question 323

Medical Conditions that present as Anxiety

Answer 323

- hyperthyroidism - hypoglycemia - Pheochromocytoma - hypercortisolism - cardiac arrhythmia

Question 324

Integrins

Answer 324

Bind to specific proteins = collagen, fibronectin, and laminins, cadherins, selectins, and Ig superfamily members

Question 325

Aspergilloma

Answer 325

Colonize and develop in old lung cavities from TB, emphysema, and sarcoidosis - forms fungus ball without lung tissue invasion - radiopaque structure that shifts when the patient changes position - might cause cough and hemoptysis

Question 326

Q fever

Answer 326

- myalgia, fatigue, Fever >10 days - retroorbital headache with a normal leukocyte count - thrombocytopenia and increased liver enzymes

Question 327

Tetralogy of Fallot

Answer 327

The degree of right ventricular outflow tract obstruction is the major determinant of the degree of right to left intra cardiac shunting and resultant cyanosis

Question 328

G protein receptors and integral membrane proteins

Answer 328

Contain transmembrane domains composed of alpha helicase with hydrophobic amino acid residues (alanine, valine, isoleucine, phenylalanine, tryptophan, methionine, proline, glycine) = these transmembrane domains help anchor the protein to the phospholipid bilayer of the cell membrane

Question 329

Heparin

Answer 329

Both unfractionated heparin and LWMH (enoxaparin) can bind to antithrombin to increase its activity against Factor 10a = but only unfractionated heparin is able to bind to both antithrombin and thrombin to allow antithrombin to inactivate thrombin

Question 330

Obstructive Lesion in a Mainstem bronchus

Answer 330

Can prevent ventilation of an entire lung leading to obstructive atelectasis and complete lung collapse Chest X Ray will show unilateral pulmonary opacification and deviation of the mediastinum toward the pacified lung

Question 331

Demyelination Principles

Answer 331

Length constant = space constant - measure of how far along an axon an electrical impulse can propagate - demyelination will decrease the length constant and result in impaired stimulus transmission

Question 332

HbS

Answer 332

Valine substitution promotes hydrophoic interaction among Hb molecules and results in HbS polymerization and erythrocytes sickling

Question 333

Hydralazine Side Effect

Answer 333

- Reflex Sympathetic Activity - causing fluid retention Don't give to angina/CAD patients - lupus like syndrome

Question 334

LAD reconstruction

Answer 334

- if just one = use left internal mammary (thoracic) artery - if multiple arteries need reconstruction = breath sap heinous vein Great saphenous vein it's located inferolateral to the pubic tubercle - coarses anterior to the medial malleolus Femoral triangle - inguinal ligament superiority - sartorious muscle laterally - adductor long us muscle medially

Question 335

Cystic Fibrosis AGAIN

Answer 335

In Respiratory and Gastric Glands - impaired functioning of the CFTR protein reduces luminal chloride secretion and increases sodium and net water absorption, resulting in dehydrated mucus and a more negative transepithelial potential difference In sweat glands - abnormal CFTR function causes reduced salt absorption, leading to the production of hypertonic sweat with high chloride content.

Question 336

Allergic Bronchopulmonary Asperfillosis

Answer 336

- occurs in 5-10% of corticosteroid dependent asthmatics - patient have high serum IgE levels, eosinophilia, and IgE plus IgG antibodies to Aspergillus - there is intense airway inflammation and mucus plugging with exacerbations and remissions - repeated exacerbations may produce transient pulmonary infiltrates and proximal bronchiectasis

Question 337

Polysaccharide capsular vaccines

Answer 337

- S. Pneumonia - H. Influenza - N. Meningitidis

Question 338

Hepatocellular Carcinoma

Answer 338

- World wide, the countries that have high rates of hepatitis B virus (HBV) infection have more than 85% of all Hepatocellular carcinoma cases. - The people that develop HCC in these countries usually have chronic HBV infection acquired through vertical transmission at childbirth, which increases their risk of developing HCC by early to middle adulthood 200-fold - In these countries with high rates of HBV infection, HCC commonly presents in adults 20-40 years old - So universal vaccination of children against HBV would be the one measure most likely to cause a steep decline in the incidence of Hepatocellular carcinoma worldwide

Question 339

Primary Aldosteronism

Answer 339

- Hypernatremia never occurs due to aldosterone escape

Question 340

ARea postrema

Answer 340

- the central emetic center is in the dorsal surface of the medulla at the caudal end of the 4th ventricle

Question 341

IV drugs

Answer 341

Highly lipophilic drugs - it is rapidly cleared from the plasma and preferentially distributed to organs receiving high blood flow (Brain, heart, liver, and kidneys) - this initial distribution accounts for the rapid onset of sedation seen with administration - over time propofol is redistributed to. Organs receiving less blood flow (skeletal muscle and skin) - then lastly bone, adipose and connective tissue IV anesthetics are eliminated through the liver Inhaled anesthetics are eliminated through the lungs The neuromuscular blocking agents spontaneously degrade in plasma and organ tissue, a type of metabolism known as Hoffman elimination

Question 342

TMP-SMX

Answer 342

Is associated with bone marrow suppression

Question 343

The treatment of Choice for Diabetic Ketoacidosis

Answer 343

- IV normal saline and insulin | - these therapies increase serum bicarbonate and sodium and decrease serum glucose, osmolarity and potassium

Question 344

PCR

Answer 344

Used to amplify small fragments of DNA - you first need a source DNA template that includes the target region to be amplified as well as flanking sequences adjacent to the target region - the oligonucleotide sequence of these flanking regions must be known in order to make the primers necessary to start PCR

Question 345

Left or Right nasal hemianopia

Answer 345

Will occur with aneurysm from internal carotid artery - will cause ipsilateral nasal hemianopia by damaging uncrossed optic nerve fibers from the temporal portion of the retina

Question 346

Calcium Channel Blocker Side effects

Answer 346

Include headache, flushing, dizziness, and peripheral edema - development of peripheral edema occurs due to preferential dilation of pre capillary vessels (arteriolar dilation) this leads to increased capillary hydrostatic pressure and fluid extravasation into interstitium

Question 347

Abdominal Aortic Aneurysms

Answer 347

Characterized by Transmural inflammation of the aortic wall - chronic inflammation leads to degradation of elastin and collagen by proteases, resulting in loss of elastin and smooth muscle cells and abnormal collagen remodeling and cross-linking - These changes lead to weakening and progressive expansion of the aortic wall resulting in aneurysm formation

Question 348

Middle episiotomy

Answer 348

The perineal body is a fibrous ulnar tissue between the urogenital and anal triangle - a midline episiotomy is a vertical incision from the posterior vaginal opening to the perineal body - it transacts the vaginal submucosal tissue but not the external anal sphincter or the rectal mucosa

Question 349

Nafcillin, Oxacillin, Methicillin, and Dicloxacillin

Answer 349

- Have bulky R groups that prevents Beta Lactamases - the only way resistance can be conferred is if there is altered penicillin binding proteins which are resistant to the drug - the penicillin binding protein is where it binds

Question 350

Low Vd (3-5L)

Answer 350

- characteristics of a drug such as high molecular weight, high plasma protein binding, high charge, and hydrophilicity tend to trap the drug in the plasma compartment

Question 351

Heparin Overdose

Answer 351

You can't give fresh frozen plasma because it contains antithrombin 3 which enhances heparin effect Give protamine = effective

Question 352

Pre tibial Myxedema

Answer 352

Will cause lower leg skin thickening and induration | - seen in hyperthyroidism due to grave's disease

Question 353

Carpal Tunnel Syndrome

Answer 353

Associated with conditions that reduce carpal tunnel space, including pregnancy (fluid accumulation), hypothyroidism (GAG buildup), diabetes (connective tissue thickening), and rheumatoid arthritis (tendon inflammation) - patients with a long history of hemodialysis can also develop median nerve compression through deposition of Beta 2 microglobulin in the carpal tunnel

Question 354

Rickettsia and Chlamydia

Answer 354

Are intra cellular organisms because they can't make their own ATP

Question 355

Obligate Anaeorobes

Answer 355

Lack catalase and Superoxide dismutase

Question 356

Mycobacterium Kasasii

Answer 356

Pulmonary TB-like symptoms in COPD patients

Question 357

Mycobacterium scrofulaceum

Answer 357

Causes cervical lymphadenitis in children

Question 358

Mycobacterium Marinum

Answer 358

Hand infection in aquarium

Question 359

Hepatitis D

Answer 359

Considered replication defective because it must be coated by external coat hepatitis B surface antigen of HBV to penetrate the hepatocyte -

Question 360

CCL4 poisoning

Answer 360

CYP450 will produce free radicals that start a vicious cycle of hepatic injury = lipid peroxidation CCL4 injury develops rapidly and leads to swelling of the ER, destruction of mitochondria, and increased permeability of cell membranes. This causes hepatocyte necrosis

Question 361

Aspirin Toxicity

Answer 361

Would caused a mixed respiratory alkalosis and non anion gap metabolic acidosis so the pH would normal

Question 362

Occulomotor Nerve

Answer 362

- Has parasympathetic fibers inside it Uncal herniation will cause a dilated pupil

Question 363

Gastric Bypass Surgery

Answer 363

Can cause small intestinal bacterial overgrowth (SIBO) due to excessive bacterial proliferation in the blind-ended GI segment. SIBO results in deficiency of most vitamins (B12, A, D, and E) and iron, but increased production of folic acid and vitamin K

Question 364

Varicose Veins

Answer 364

Can cause lower extremity edema due to venous stasis - common complications resulting from poor blood flow include painful thromboses, stasis dermatitis, skin ulceration, poor wound healing, and superficial infections - venous stasis ulcers often occur over the medial malleolus - varicose vein thromboses are restricted to the superficial venous system

Question 365

EBM

Answer 365

``` Reproducibility = reliability Validity = Accuracy ```

Question 366

Common Peroneal Nerve Injury

Answer 366

Foot drop and stoppage gait

Question 367

Recurrent C. Diff Infection Treatment

Answer 367

Fidaxomicin is used primarily in recurrent CDI and is bacteriocidal with minimal systemic absorption - a macrocyclic antibiotic (related to macrolides) that inhibits the sigma subunit of RNA polymerase, leading to protein synthesis impairment and cell death - it is an oral drug with bacteriocidal activity, minimal systemic absorption and a narrow spectrum it has less effect on normal colonic flora than either metronidazole or vancomycin

Question 368

Lactase Deficiency

Answer 368

- elevated stool osmotic gap - decrease in stool pH because the bacteria Ferment lactose to produce short chain fatty acids - increase in hydrogen gas which causes flatulence

Question 369

Nucleolus

Answer 369

All rRNA is made in the Nucleolus

Question 370

Abetalipoproteinemia

Answer 370

- will see clear or foamy cytoplasm in the intestinal epithelium

Question 371

Peripheral Neuropathy

Answer 371

Toxin penetration through the blood-nerve barrier leading to peripheral neuropathy occurs with diphtheria Hyalinization of nerve arterioles is seen in diabetes mellitus (diabetic microangiopathy) = leads to the narrowing of the arterial lumen and ischemic nerve injury = one mechanism of diabetic neuropathy Guillain barre = acute demyelination peripheral neuropathy. Segmental demyelination and an endometrial inflammatory infiltrate seen on light microscope

Question 372

Digoxin

Answer 372

Used for ventricular rate control in atrial fibrillation as it decreases AV conduction by increasing PSNS vagal tone - Digoxin slows the ventricular rate during atrial fibrillation by enhancing vagal tone which leads to the inhibition of AV nodal conduction

Question 373

Succinylcholine

Answer 373

- can cause significant potassium release and life threatening arrhythmias in patients at high risk for hyperkalemia, including those with burns, myopathies, crush injuries, and denervation injuries or disease

Question 374

Thiazide Diuretics

Answer 374

Can cause hypokalemia and lead to significant muscle weakness, cramps, and rhabdomyolysis

Question 375

Cox 2

Answer 375

Is an inducible enzyme that is undetectable in most tissues except in cases of inflammatory cell activation FYI COX1 creates constitutive prostaglandins COX2 creates inducible prostaglandins

Question 376

Her2

Answer 376

Oncogene Tyrosine Kinase Receptor 185-kD transmembrane glycoprotein that has intra cellular tyrosine kinase activity It is one of the epidermal growth factor receptors that play a role in the activation and control of epithelial growth and differentiation = increased rates of breast and ovarian cancer

Question 377

Growth Factors that increase angiogenesis in neoplastic tissue

Answer 377

VEGF AND FGF Also pro inflammatory cytokines IL-1 and IFN-gamma can indirectly promote angiogenesis through increased expression of VEGF

Question 378

Roseola HHV6

Answer 378

Fever for 4-5 days then maculopapular rash. Some may get seizures

Question 379

Heterophile antibody negative mononucleosis like syndrome

Answer 379

Most likely it is cytomegalovirus - CMV can be acquired via transfusions by leukocyte laden blood products because the virus infects leukocytes of granulocyte macrophage lineage - other causes are HHV6, HIV, and toxoplasmosis

Question 380

Tetanus Diagnosis

Answer 380

Pure Clinical via History and Exam - no other way to diagnose

Question 381

Pelvic Floor Muscles

Answer 381

Kegal exercises help strengthen the pelvic floor muscles - levator ani = iliococcygeus, pubococcygeus, puborectalis - these muscles hold the bladder and the urethra in the proper Anatomic position - injury to these muscles can result in urethral hypermobility which can lead to stress incontinence

Question 382

Non-small cell lung cancer

Answer 382

Some patients may have a chromosomal rearrangement that creates a fusion protein EML4 and ALK THIS RESULTS IN CONSTANT TYROSINE KINASE THAT CAUSES MALIGNANCY

Question 383

Supracondylar Fracture

Answer 383

Lateral displacement = radial nerve | Medial displacement = medial nerve and brachial artery

Question 384

Telomerase

Answer 384

RNA DEPENDENT DNA POLYMERASE that consists of 2 components 1. Telomerase reverse transcriptase 2. Telomerase RNA