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Flashcards in 2015.04.12 Deck (39)
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1
Q

Indirect Inguinal Hernia

A

Male infants

Enters internal inguinal ring lateral to inferior epigastric vessels.

Caused by persistent processus vaginalis & failure of internal inguinal ring to close.

Covered by all 3 spermatic fascial layers

2
Q

Direct Inguinal hernia

A

Occurs in older men.

Bulges through Hesselbach’s triangle, medial to inferior epigastric vessels, to reach external inguinal ring.

Caused by weakness of the transversalis fascia.

Covered only by external spermatic fascia.

3
Q

Femoral Hernia

A

Occurs in women

Protrudes through the femoral ring, medial to the femoral vessels & inferior to the inguinal ligament.

4
Q

Endothelial Nitric Oxide Synthase (eNOS)

A

Stimulated by increase in cytosolic calcium levels (due to acetylcholine, bradykinin, serotonin, substance P or shear froces which activate specific membrane receptors).

Synthesizes nitric oxide from argininge, NADPH, O2.

NO activates guanylyl cyclase and increases cGMP. Activate protein kinase G, reduces cytosolic calcium levels and relaxation of vascular smooth muscle.

5
Q

Follicular Lymphona

A

Non-hodgkin lymphoma of follicular B-lymphocytes.

t(14;18) causing Bcl-2 overexpression (protooncogene because of its anti-apoptotic effefcts)

6
Q

“Water-hammer” pulses and head-bobbing with each heart beat (de Musset sign)

A

Aortic regurgitation

Large left ventricular stroke volume (LVSV), large regurgitant SV, large pulse pressure.

Left ventricular end diastolic volume also increased.

Bounding femoral and carotid pulses marked by abrupt distention and quick collapse (“water-hammer” are the result of large pulse pressure.

LVSV causes the head-bobbing with carotid pulsations due to transfer of momentum.

7
Q

Gallbladder hypomotility

A

Risk factors: pregnancy, rapid weight loss, prolonged use of total parenteral nutrition or octreotide, and high spinal cord injuries.

Formation of biliary sludge due to bile precipitation - contains cholesterol monohydrate crystals, calcium bilirubinate, and mucus.

8
Q

Glucocorticoid acute effects on CBC

A

Increased neutrophil count due to “demargination” (neutrophils previously attached to the vessel wall)

Decreased lymphocyte, monocyte, basophil and eosinophil counts.

9
Q

Viridans Streptococci

A

normal inhabitants of oral cavity.

capable of producing extracellular polysaccharides (dextrans) using sucrose as a substrate.

Dextrans facilitate streptococcal adherence to fibrin.

Fibrin and platelets are deposited at sites of endothelial trauma (pre-existing valve damage), providing a site for bacterial adherence and colonization, leading to formation of valvular vegetation.

S. aureus is more aggressive and can adhere to intact endothelium without prexisiting lesion.

10
Q

P bodies

A

distinct foci within eukaryotic cells involved in mRNA regulation and turnover.

role in translation repression and mRNA decay

contain RNA exonucleases, mRNA capping enzymes, and consitituents involved in mRNA quality control and microRNA-induced mRNA silencing.

Storage of mRNA

11
Q

CD14

A

surface marker of monocyte-macrophage cell lineage

12
Q

Filtration Fraction

A

GFR/RPF

13
Q

Characteristics of a drug that traps drug in plasma compartment, resulting in low volume of distribution

A

High molecular weight

High plasma protein binding

High charge

Hydrophilicity (charged)

14
Q

Blunt Aortic Injury (Traumatic Aortic rupture)

A

Most commonly caused by motor vehicle collisions

Injury most often at aortic isthmus (tethered by the ligamentum arteriosum - relatively fixed and immobile compared to descending aorta)

Due to sudden deceleration

Widened mediastinum may be seen on x-ray

15
Q

Where do atherosclerotic plaques predominantly develop?

A

Large elastic arteries and large/medium sized muscular arteries.

  1. Abdominal aorta
  2. coronary arteries
  3. popliteal arteries
  4. internal carotids
  5. circle of willis
16
Q

Cardiovascular toxicity due to TCA (anti-depressant)

A

QRS and QT prolongation and cardiac dysrhythmias

Due to inhibition of fast sodium channels.

Treatment: hypertonic sodium bicarbonate to correct QRS prolongation, reverse hypotension and treat ventricular dysrhythmias

17
Q

Multiple Myeloma

A

Plasma cells (characteristic with basophilic cytoplasm, eccentric nuclei, “wagon wheel”/”clock face”) infiltrate the bone marrow.

Normocytic, normochromic anemia - due to bone marrow infiltration

Bone resorption - due to osteoclast activation by IL-1 and IL-6 by neoplastic cells.

Hypercalcemia - due to bone destruction

Increased susceptibility to infection - monoclonal immunoglobulin production (M protein and Bence-Jones protein)

AL amyloid - due to accumulation of monoclonal Ig light chains.

Renal failure - infiltration of kidney

18
Q

What does pulmonary capillary wedge pressure (PCWP) measure?

A

Left atrial EDP, which under normal conditions is nearly equal Left ventricle EDP.

Mitral stenosis elevates LAEDP and PCWP relative to LVEDP.

19
Q

Primaquine

A

eradicate the intrahepatic stages (latent hypnozoites) of P. vivax and P. ovale.

Chloroquine is used for treatment of susceptible erythrocytic forms (trophozoites, merozoites) of all Plasmodia species.

20
Q

Nitroprusside

A

agent of choice in treating hypertensive emergency.

metabolized to cyanide, with subsequent conversion to thiocyanate by liver rhodanase.

risk of cyanide toxicity. treated with Sodium thiosulfate which donates sulfur to liver rhodanase to enhance conversion of cyanide to thiocyanate

21
Q

Common disease-causing intracellular organisms

A

Chlamydia, Legionella, Listeria monocytogenes, Mycobacterium, Neisseria meningitidis, Nocardia, Rickettsia, Salmonella typhi

Cryptococcus neoformans, Histoplasma capsulatum, Pneumocystis jirovecii

Plasmodium, Toxoplasma gondii

22
Q

Listeria Monocytogenes

A

Facultative intracellular, Gram + rod, B-hemolysis (like Streptococcus agalactiae)

Immotile at 37C but demonstrates tumbiling motility at 22C. Also can multiply at temps as low as 4C.

Listeriolysin O - pore forming toxin that allows Listeria to lyse the vacoular membrane and stay intracellular.

Listeria stimulates production of cytokines that induce a cell-mediated immune response leading to killing of intracellular Listeria. In patients with compromised cell-mediated immunity, the organism survives.

23
Q

Lymphatic drainage of the scrotum

A

Superficial inguinal lymph nodes. (drain all cutaneous lymph from the umbilicus to the feet, including external genitalia and anus)

24
Q

Lymphatic drainage of testes

A

Para-aortic (retroperitoneal) lymph nodes

25
Q

Lymph drainage from glans penis and cutaneous portion of the posterior calf

A

Deep inguinal lymph nodes.

26
Q

Miosis

A

Pupillary constriction (can be caused by a1 antagonist)

27
Q

Mydriasis

A

Contraction of pupillary dilator muscle, causing pupillary mydriasis

28
Q

Haemophilus influenzae type b

A

Has a capusle composed of linear polymer composed of ribose, ribitol, and phosphate (Polyribosyl-ribitol-phosphate).

Epiglottitis is due to an acute infection, with an abrupt onset of obstructive laryngeal edema.

Vaccine is PRP conjugated with diptheria or tetanus toxoid.

29
Q

Vimentin

A

Intermediate filament present in mesenchymal tissue

30
Q

Chromogranin A and neuro-specific enolase

A

markers for neuroendocrine tumors

31
Q

HER2/neu oncogene

A

transmembrane glycoprotein that has intracellular tyrosine kinase activity.

one of the epidermal growth factor receptors that play a role in activation of epidermal transduction pathways that control epithelial growth and differentiation.

32
Q

Clathrin

A

intracellular cytosolic protein that mediates endocytosis

33
Q

Peudogout (Calcium pyrophosphate deposition disease)

A

accumulation of calcium pyrophosphate crystals in synovial fluid.

distinguished from gout: knee joint involved, but no first metatarsophalangeal joing involvement.

WBCs increased, with neutrophilic predominance.

Rhomboid-shaped calcium pyrophosphate crystals are diagnostic. Crystals are birefringent under polarized light.

34
Q

Gout

A

Monosodium urate (salt of uric acid) deposits in joings and soft tissues causing symptoms.

First metatarsophalangeal joint is more frequently involved in gout.

35
Q

Calcific tendonitis

A

Deposition of calcium hydroxyapatite crystals in periarticular soft tissues (especially tendons, like rotator cuff tendons)

36
Q

Calcium oxalate

A

Most common constituent of renal calculi

37
Q

Calcium pyrophosphate, hydroxyapatite, oxalate

A

pyrophosphate - pseudogout

hydroxyapatite - gout

oxalate - renal canaliculi

38
Q

Nitrates and Phosphodiesterase Inhibitors

A

Both cause increase in intracellular cGMP which causes vascular smooth muscle relaxation.

39
Q

Inositol triphosphate second-messenger system

A