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Flashcards in 5/21 Mixed Deck (21):
1

Strep pneumoniae vaccine

-give to young children and elderly
Pneumococcal polysaccaride vaccine is an unconjugated vaccine that induces a relatively T-cell independent response
The pneumoccocal conjugate vaccine contains polysaccharide material attached to a protein antigen which allows for a more robust T-cell dependent resposne

2

Thoracic outlet syndrom

Compression of the lower trunk of the brachial plexus in the scalene triangle, the space bordered by the anterior and middle scalene muscles and the first rib.
Symptoms include upper extremity numbness, tingling and weaknessDue to anomalous cervical rib, scalene muscular anomalies, injury (repetitive overhead arm movements, trauma)

3

The gonadal arteries arise from

The abdominal aorta

4

Turner's Syndrome

Lymphedema (bilateral non-pitting edema of hands and feet) and cystic hygromas (posterior neck mass composed of cystic space sepatated by connective tissue)
Short stature, primary amenorrhea, and aortic anomalies are the other important clinical features
Femoral pulses are diminished = coarctation of the aorta

5

Inflammation

Passage of circulating inflammatory leukocytes into the inflamed tissue
Steps involved: margination, rolling, activation, tight adhesion, crawling, transmigration

Transmigration is mediated by adherence to platelet endothelial cell adhesion molecule 1 (PECAM-1)

6

Allopurinol effects on azathioprine

Xanthine Oxidase (XO) catalyzes 1 of 2 major azathioprine-inactivating pathways
Allopurinol competitively inhibits XO, which results in increased conversion of azathioprine to its active metabolite

7

Zinc finger motifs

Composed of chains of amino acids bound together around a zinc atom via linkages with cysteine and histidine residues
They recognize specific DNA sequences and are used by many transcription factors to bind DNA and alter activity of target genes
Intracellular receptors that bind steroids, thyroid hormone, and fat soluble vitamins act directly as transcription factors and contain zinc-finger binding domains

8

Mannitol

Osmotic diuretic that works by increasing plasma or tubular fluid osmolality
Increased plasma and fluid osmolality causes extraction of water from the interstitial space into the vascular space or tubular lumen, with subsequent diuresis
In the brain, water redistribution from the tissues into the plasma helps reduce edema and intracranial pressure in the setting of cerebral edema
One of the more severe toxicities of aggressive osmotic diuretics is pulmonary edema

9

Microglia

Move to the area of ischemic infarct approximately 3-5 days after the onset of ischemia and phagocytize the fragments of neurons, myelin and necrotic debris
A cystic space replaces the necrosis and astrocytes form a glial scar along the periphery

10

Chronic Aortic regurgitation

Leads to an increase in left ventricular end-diastolic volume (preload) and wall stress, with resultant ECCENTRIC hypertrophy. The gradual increase in left ventricular chamber size increases total stroke volume and helps maintain cardiac output

CONCENTRIC HYPERTROPHY: Pressure overload
ECCENTRIC HYPERTROPHY: Volume overload

11

Brain Natriuretic Peptide (BNP)

Causes vasodilation (decreased preload) and diuresis
Both ANP and BNP activate guanylate cyclase, which induces an increase of intracellular cyclic GMP

12

Clostridium difficile contact precautions

Hand washing with soap and water, gown for any patient contact, and non-sterile gloves that should be changed after contact with contaminated secretions.
Alcohol-based hand sanitizers do not kill the bacterial spors

13

Obesity hypoventilation syndrome

Characterized by chronic fatigue, dyspnea, difficulty concentrating, and evidence of hypoventilation (partial pressure of carbon dioxide > 45 while awake)
It is one of the important causes of hypoxemia with a normal alveolar to arterial oxygen gradient

14

Tumor lysis syndrome

Can develop during chemo for cancers with rapid cell turnover (poorly differentiated lymphomas and leukemas), substantial tumor burden, or high sensitivity to chemotherapy
It is characterized by hyperphosphatemia, hypocalcemia, hyperkalemia, hyperuricemia
Prevention often involves hydration and the use of a hypouricemic agents such as allopurinol and rasburicase

15

Isosorbide dinitrate

Low bioavailability due to extensive first-pass hepatic metabolism prior to release in systemic circulation (requires a higher dose)
Sublingual nitroglycerin is absorbed directly from oral mucosa into the venous circulation and has a higher bioavailability

16

Carotid sinus massage

Leads to an increased afferent firing from the carotid sinus, which increases vagal parasympathetic tone causing temporary inhibition of the SA node, slowing of conduction through the AV node, and prolongation of the AV node refractory period
Useful for termination of paroxysmal supraventricular tachycardia

17

Holoprosencephaly (HPE)

Incomplete division of the forebrain into 2 hemispheres
Ocular hypotelorism, cleft lip/palate, single midline eye, primitive nasal proboscis, mid facial clefts
Likely caused by a combination of genetic (trisomy 13, sonic hedgehog gene mutations) and environmental (maternal alcohol use during pregnancy)
Example of MALFORMATION (primary intrinsic defect in the cells or tissues that form a structure)

18

Cause of gallbladder stones in somatostatinoma

Due to reduced gallbladder contractility, due to decreased cholecystokinin secretion

19

Acute tubular necrosis

Can be caused by decreased renal perfusion due to severe hypovolemia, shock, or surgery
The straight proximal tubules and the thick ascending limb of Henle's loop located in the outer medulla are the most commonly affected portions of the nephron
Muddy brown casts are pathognomonic for acute tubular necrosis

20

Ductal carcinoma in situ

Ducts distended by pleomorphic cells with prominent central necrosis that do not penetrate the basement membrane
It is the precursor to invasive ductal carcinoma, the most common type of breast cancer

21

Increased bone marrow erythropoiesis

Results in accelerated release of immature red blood cells (reticulocytes) in the bloodstream
Reticulocytes contain bluish cytoplasm and reticular precipitates of residual ribosomal RNA