Amboss Hints Flashcards
Lambert-Eaton myasthenic syndrome (LEMS) pathophysiology?
Autoantibodies agains P/Q voltage-gated calcium channels at the myoneural junction that impair the release of acetylcholine
Why clinical signs of cyanosis occurs as a result of inhaled NO?
(The mainstay treatment for PPHN)
Because NO causes oxidation of ferrous iron (Fe2+) to ferric iron (Fe3+) at high levels, resulting in the formation of methemoglobin
What is the most common upper extremity neuropathy?
CTS
Carpal tunnel syndrome
What conditions are associated with carpal tunnel syndrome?
Pregnancy
hypothyroidism
rheumatoid arthritis
acromegaly
Ulnar nerve entrapment occurs at…….?
1) cubital tunnel in the elbow
2) ulnar tunnel (Guyon’s canal) in the hand
What nerve injury causes wrist drop?
posterior interosseous nerve (PIN), a branch of the radial nerve
Key features for differentiating HHS and DKA?
1)DKA:ketones are formed because there is no endogenous insulin
HHS برعکس
2)DKA: lower Bicarbonate
B2 deficiency symptoms?
seborrheic dermatitis (erythematous rash with fine yellow scales)
pharyngeal hyperemia
glossitis, cheilitis, angular stomatitis,
normocytic-normochromic anemia The increased activity coefficient of erythrocyte glutathione reductase confirms this diagnosis.
riboflavin (vitamin B2) serves as a redox cofactor for various enzymes, including …..?
pyruvate dehydrogenase α-ketoglutarate dehydrogenase succinate dehydrogenase glutathione reductase
Vitamin B5 deficiency symptoms
Adrenal insufficiency
Enteritis
Alopecia
Neurological symptoms (paresthesias, numbness)
Pyridoxal phosphate, the active form of vitamin B6, is used as a cofactor, for ….?
cysthathione synthesis, protein catabolism, and heme synthesis
Vitamin B6 deficiency symptoms?
stomatitis, cheilosis
seborrheic dermatitis
sideroblastic anemia due to impaired heme synthesis, which is microcytic, not normocytic. Diagnosis is confirmed by direct measurement of plasma pyridoxal phosphate concentration
Niacin deficiency is confirmed by measuring …
serum levels of tryptophan or erythrocyte NAD/NADP ratio.
Diagnosis of B1 deficidncy can be confirmed by …
measuring the transketolase activity in RBCs following administration of thiamine.
What is the most common side effect of topical corticosteroid use
Skin thinning
What is the MOA of corticosteroids?
bind to intracellular glucocorticoid receptors, forming a complex that translocates into the nucleus, where it interacts with specific DNA sequences. The complex :
1)activates IκB, which inhibits the function of NF-κB, a transcription factor that normally promotes expression of numerous pro-inflammatory cytokine genes. 2)It also inhibits production of arachidonic acid derivatives by inhibiting phospholipase A2.
Chronic, systemic corticosteroid use is associated with increased risk of developing cutaneous SCC and BCC but not dysplastic nevi or melanoma.
Topical corticosteroid use is not known to increase the risk of any skin cancer type.
What translocation can be seen in 75% of Burkitt lymphoma?
Risk factors?
t(8;14) , which results in c-myc gene dysregulation on chromosome 8. C-myc is a proto-oncogene .
1) chronic EBV infection predisposes to translocation t(8;14).
2) Sporadic Burkitt lymphoma is associated with HIV
Diseases due to translocations?
8,14 burkitt 14,18 follicular lymphoma 9,22 CML 11,14 mantle cell lymphoma 11,22 Ewing sarcoma 15,17 acute promyelocytic leukemia (APL) 12,21 ALL
Anemia in vitamin deficiency
B2 normocytic
B6 microcytic
B9,B12 macrocytic
