March 29 Flashcards Preview

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Flashcards in March 29 Deck (43):
1

What cells are characteristic of Langerhans cell histiocytosis and what do they express/stain for?

Birbeck granules--tennis rackets/rod shaped on EM

Express S-100 and CD1a

2

What 3 symptoms are common with Whipple disease and what is seen on histo?

Cardiac symptoms
Arthralgias
Neurologic symptoms

PAS + foamy macrophages in intestinal lamina propria with rod shaped inclusion bodies

"Foamy Whipped cream in a CAN"

3

What are the 2 possible causes of Phenylketonuria (PKU), which presents with intellectual disability, growth retardation, seizures, fair skin, eczema, and musty body odor (caused by disorder of aromatic amino acid metabolism)? Also, what is tx?

Due to decreased phenylalanine hydroxyls or decreased tetrahydrobiopterin cofactor

Tx: decreased phenylalanine and increased tyrosine in diet
--Tetrahydrobiopterin supplementation if due to latter

4

What is affect in I-cell disease?

Failure of golgi to phosphorylate mannose residues

5

What nerve is damage when pt has winged scapula and where does this nerve originate?

Long thoracic nerve--originates from C5, C6, C7
--innervates the serratus anterior muscle which keeps scapula against thoracic rib cage

Common injury from mastectomy --axillary node dissection

6

What is the target for imatinib and what is it used to treat?

bcr-abl tyrosine kinase--inhibitor

Used for chronic myelogenous leukemia--seen in older adults and is caused by Philadelphia chromosome--t9;22 BCR-ABL

7

What are gap junctions composed of?

Connexons--allow for rapid chemical and electrical signals btw cells

8

What type of HSR is involved in blood transfusion incompatibility?

Type II HSR--Complement mediated

9

Damage to what upper extremity nerve results in loss of forearm flexion and supination and loss of sensation over lateral forearm?

Musculocutaneous --C5-C7

10

What antineoplastic agent that is a monoamine oxidase inhibitor can cause hypertensive crisis if taken with tyramine- rich foods?

Procarbazine

11

What do Peyer patches contain that sample and present antagonist to immune cells?

M cells--production of IgA to deal with intraluminal antigen

12

What are the ECG findings seen with cardiac tamponade?

Low-voltage QRS and electrical alternans--due to swinging movement of heart in large effusion

Presents with Beck triad
-Hypotension
-Distended neck veins
-Distant heart sounds

--Also pulsus paradoxus

13

What disease is characterized by switching from breastfeeding to formula or whole food in infant and how does this dz present?

Fructose intolerance caused by deficiency of aldolase B

Pt vomits and is lethargic after ingestion of fructose
Pt can have severe hypoglycemia and jaundice--may progress to cirrhosis

14

What is the MOA of amantadine for the tx of Parkinson's?

Increased DA release and decreases DA reuptake

15

Monoamine oxidase inhibitors that can cause hypertensive crisis if taken with tyramine?

Tranylcypromine
Phenelzine
Isocarboxazid
Selegiline

"MAO Takes Pride In Shanghai"

16

What is the most common cause of appendicitis in a child?

Lymphoid hyperplasia --commonly occurs after viral infection--adenovirus, measles or vaccination

17

What enzyme deficiency results in lack of secondary sexual development on females and elevated blood pressure and where in the adrenal cortex is the increased substance coming from causing symptoms?

17a-hydroxylase deficiency--resulting in overproduction of mineralocorticoids from the zona glomerulosa and increased BP and decreased production of sex hormones

18

What phase of the cell cycle do oocytes remain in from birth to ovulation?

Prophase I of meiosis

19

What phase of the cell cycle do oocytes remain in from ovulation until fertilization?

Metaphase II of meiosis

20

What does the Mesonephric (Wolffian) duct develop into?

Into male internal structures--EXCEPT prostate
BEEDS
-trigone of Bladder
-Epididymis
-Ejaculatory duct
-Ductus deferens
-Seminal vesicles

21

On lineweaver-burk plot what does a competitive inhibitor show?

Increased Km with maintenance of Vmax

Km will move right because -1/Km becomes less negative--decreasing affinity for substrate

22

What state of glutathione detoxifies free radicals?

Reduced glutathione

23

What is damage when a person is unable to repeat a sentence but all other language and comprehension is intact?

Conduction aphasia--damage to the arcuate fasciculus

24

What drug is used for HER-2 + breast cancer and what is its MOA?

Trastuzumab--monoclonal antibody against HER-2, a tyrosine kinase receptor
--helps kill cancer cells that overexpress HER-2 through inhibition of HER-2-initiated cellular signaling and antibody-dependent cytotoxicity

25

What is the presentation for Kawasaki disease and how is it treated?

Conjunctival injection
Rash
Adenopathy--cervical
Strawberry tongue
Hand-foot changes--edema and erythema
Fever

"CRASH and burn"

Tx: Aspirin and IVIg

26

What is hemiballismus and what causes it?

Sudden, wild flailing of 1 arm caused by contralateral sub thalamic nucleus lesion--lacunar stroke

27

What is the cause of severe combined immunodeficiency (SCID), which presents with failure to thrive, chronic diarrhea, thrush, absence of thyme shadow, germinal centers and T cells?

Defective IL-2R gamma chain or adenosine deaminase deficiency

28

What hormones are abnormal with Klinefelter syndrome (XXY)?

decreased inhibin B--> increased FSH
Abnormal Leydig cell function --> Decreased testosterone--> increased LH--> increased estrogen

29

What immunoglobulin is elevated in multiple myeloma and why?

IgG--neoplastic proliferation of plasma cells which produce mostly IgG

30

Loss of what allows for proteinuria seen with minimal change disease?

Disruption of negative charged heparan sulfate--negatively changed albumin is no longer repelled causing protein in the urine

31

What ligament if weakest/most likely to be damage with injury to the ankle?

Anterior talofibular ligament--causes talus to be displaced forward

32

What essential amino acid can donate methyl groups?

Methionine

33

What are the essential amino acids?

PVT TIM HALL

Phenylalanine
Valine
Threonine
Tryptophan
Isoleucine
Methionine
Histidine
Arginine
Leucine
Lysine

34

What organelle is involved in catabolism of very-long-chain fatty acids and if there is a disorder in this organelle there can be an affect on myelin sheath formation?

Peroxisome
--Refsum dz--present with progressive neurologic damage at a young age

35

Aschoff bodies are seen in what disease?

Rheumatic fever
--Granuloma with giant cells

Also seen anitschkow cells--enlarged macrophages with ovoid, wavy, rod-like nucleus

36

What are the clinical findings seen with von Willebrand disease?

Epistaxis
menorrhagia
prolonged bleeding immediately after invasive procedure

37

What drugs, used to treat schizophrenia can cause repetitive oral-facial movements?

Antipsychotics--Haloperidol and -azines
--Long term use can cause Tardive dyskinesia

38

What enzyme is deficient in Pompe disease and what are the symptoms?

Lysosomal a-1,4-glucosidase --leads to inability to breakdown stored glycogen

Build-up of glycogen in heart, skeletal muscle, brain and liver --infant suffers from hypotonia and CHF that leads to an early death

39

What drug is a member of the tetracycline family and can cause nephrogenic DI?

Demeclocycline--ADH analog

Can also cause photosensitivity and abnormalities of bone and teeth

40

Damage to what portion of the cerebellum can lead to intention tremor, limb ataxia, loss of balance causing pt to "fall toward lesion"?

Cerebellar hemisphere--cerebrocerebellum/neocerebellum

Ipsilateral deficits--fall toward side of lesion

Associated with chronic ETOH use

41

What part of the spleen contains T-cells?

Periarterial lymphoid sheath--PALS

Absent in DiGeorge syndrome--due to lack of T-cells

42

What is used to promote recovery of bone marrow in the setting of myelosuppressive cancer therapy?

Filgrastim or Sargramostin

Granulocyte colony stimulating factors (G-CSF)

43

What is Alkaptonuria and what enzyme is deficient in this disease?

Autosomal recessive disease that results in a (usually) benign pigment-forming homogentisiic acid accumulation in tissue--Bluish-black connective tissue and sclerae and urine turns black on prolonged exposure to air

Deficiency of homogentisate oxidase --responsible for degradative pathway of tyrosine to fumarate