Block 33 Flashcards
1
Q
Structures arising from neural crest cells
A
Motel PASS Melanocytes Odontoblasts Tracheal cartilage Entrochromaffin cells Laryngeal cartilage Parafollicular thyroid cells Adrenal medulla Schwann cells Spiral membrane
2
Q
Lumacaftor and ivacaftor
A
- CFTR modulating medications that can potentially help patients with CF by restoring CFTR proteins to the membrane and also by enhancing protein function at the membrane, respectively.
- the combination of these 2 medications in patients with homozygous F508 mutation has been shown to improve predicted forced expiratory volume and decrease rates of pulmonary exacerbations.
3
Q
Thalasemia
A
- hereditary hemolytic anemia resulting from defective synthesis of globin chains
- it pts with thalassemia the synthesis of either alpha or beta are defective.
- if only one gene is defective the patient will have beta thalassemia trait (beta thalassemia minor) and lack significant anemia.
- a defect in both beta globin gene results in severe hemolytic anemia known as beta thalasemia major.
- in this disease alpha chain are produced normally but they cant form stable tetramers due to the lack of beta globin chains.
- this failure to form stable hemoglobin leads to precipitation of alpha globin chains and premature lysis of RBC.
4
Q
Hormone sensitive lipase
A
- Enzyme found in adipose tissue that catalyzes the mobilization of stored triglycerides into free fatty acids and glycerol.
- HSL is inhibited by insulin, and activated by stress hormone such as glucagon.
- the stress hormone stimulate Gs protein coupled receptors on adipocytes, leading to increased cAMP production and activation of protein kinase A —> lipolysis.
- FFA and glycerol released into circulation can be taken up by the liver where the glycerol is used primarily as a carbon source for gluconeogenesis.
5
Q
Obstructive sleep apnea —> secondary polycythemia
A
-peritubular cells in the renal cortex sense hypoxia and respond by releasing erythropoietin into the bloodstream.
6
Q
Renininoma
A
Renin secreting tumor, rare , small solitary, benign juxtaglomelular cell neoplasm. They should be strongely considered in patients with marked hyperreninemia and hypertension who doesnt have renovascular disease.
7
Q
PPAR-y role in treating D.M II
A
- it binds to RXR—> PPAR-¥/RXR complex —>
- it increases FA uptake, increase adipnectin production , decrease TNF-å and decrease leptin production.
- Its role is useful in decreasing insulin resistance without increasing insulin levels.
8
Q
Uncontrolled severe asthma treatment
A
- severe asthma is defined as having symptoms throughout the day, nighttame symptoms daily, symptoms with limited activity, frequent exacerbation requiring steroids and evidence of decreased lung function on pulmonary function test.
- many asthmatics have allergies as a-trigger due to high IgE response
- anti IgE antibodies given as a subcutaneous injection (omalizumab) have been shown to be effective in moderate to severe asthma.
- this is given usually if the pts doesnt respond well to steroids and beta agonists
9
Q
Appendectomy - surgical landmarks
A
Teniae coli can be used as a surgical landmark to the appendix.
10
Q
Base excision repair
A
Its responsible for repairing various non-bulky DNA base alteration, including depurination, alkylation, oxidation, and deamination.
- excessive consumption of dietary nitrites (eg sodium nitrite), can lead to cytosine, adenine, and guanine deamination to form uracil, hypoxanthine and xanthine.
- if these abnormal bases arent removed and replaced with the correct base, DNA mutation may occur.
- BASE excision repair begins with recognition of abnormal bases by “glycosylases”, these cleave the altred DNA bases from the parent DNA molecule, leaving an empty site called AP site.
- and endonuclease then cleaves the 5’ end of the AP site, before a “layase” (phosphodiesterase) enzyme complete extraction of the AP site from the DNA molecule by removing the remaining sugar phosphate group.
- DNA polyemerase then fills the gap with the correct sugar phosphate base and final nick is sealed by “ligase”
11
Q
Prepatellar brusitis
A
“Housmaid knee”
- acute pain and localized tendreness associated with repetitive anterior knee trauma from kneeling is typical.
- its located between patella and the overlying skin. Other occupations associated with prepatellar and infrapatellar bursitis include carpet laters, mechanics and plumbers.
12
Q
Q fever
A
- human infection usually occurs through inhalation of bacteria from air contaminated by animal waste
- it has acute and chronic stages
- acute Q fever manifest as febrile illness, fever lasting >10 days, fatigue and myalgia.
- severe debilitating headaches which are often retrorbital and associated with photophobia are a frequent symptom.
- pneumonia is one of the primary signs of acute Q fever and the most common X-ray abnormality is lobar consolidation.
- leukocytes count is often normal. Other classic lab findings are increased liver enzymes and thrombocytopenia.
- chronic Q fever which is fatal if not treated and manifests as infective endocarditis in pts with valvular disease.
13
Q
SSSS
A
- its most common in infants and young children, usually not fatal unless skin lesions become secondarily infected.
- exfoliative toxins show exquisite pathalogic specificity in blistering only the superficial epidermis. They act as proteases and cleaves desmoglein in desmosomes.
- bullous impetigo is more localized form of SSSS with the bulla formation being another effect
14
Q
Theophylline intoxication
A
- its metabolized predominantly by hepatic cytochrome oxidases.
- inhibition of these enzymes by concurrent illness or other drugs (eg, cimitidne, ciprofloxacin, macrolides, verapamil, ketoconazole…) can raise serum concentration and cause theophylline toxicity.
- theophylline is a phosphodiesterase inhibitor that is sometimes used as alternate therapy for asthma.
- toxicity present as excessive CNS stimulation, GI distubances, and cardiovascular abnormalities.
15
Q
Spondyloarthritis is associated with
A
- pts with these disease have higher incidence of HLA B27 allele compared to the general population, although most patients with HLA B27 wont develop its
- they are said to have “class I HLA proteins” which are presented by all cells, on the contorary class II are only exposed by APCs and present predominantly foreign antigen to CD4 helper T cells.
16
Q
The most rapid relief from RA
A
-corticosteroids (prednisone), or NSAIDs untill DMARDS gets into effect.
17
Q
The most common congeintal breast anomalies in women and men are
A
Accessory nipple.
- they are due to failure of involution of the mammary ridge. They are usually asymptomatic however they may swell or become tender similar to normal breast tissue before or during menses.
- its identical to the normal nipple and can present with hyperpigmentation, epidermal thickening, pilosebaceous structure of montogmery areolar tubercules, smooth musle bundles and possible mammary glands and multiple ducts.
18
Q
LTC4, LTD4 and LTE4 antagonists are useful in
A
- they are useful in atopic asthma. Atopic asthma usually manifests in childhood. Of numerous inflammatory mediators postulated to play a role in the pathogenesis of allergic asthma, only leukotrines and actylcholine produce bronchospasm that is relieved by pharmacologic antagonists.
- leukotrines are synthesized by mast cells, eosinophils, basophilas and other cell types that infiltrate the bronchial mucosa in asthmatics. In addition to causing bronchial constriction and hyperreactivity.
- examples are zafirleukast and monteleukast
19
Q
Hepatitis B outcome
A
- acute hepatitis with complete resolution
- chronic hepatitis with or without cirhosis
- fulminant hepatitis with massive liver necrosis.
- the most common outcome in HBV infected adults is acute hepatitis with mild or subclinical symptoms that eventually completely resolves.
20
Q
Lactation suppression during pregnancy
A
- although lactenogenesis may begin during the second trimester, lactation is suppressed due to the high progesterone levels inhibiting the anterior pituitary.
- progesterone also inhibits LH and FSH during pregnancy.
- the drop in P after delivery allows for lactation
