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Flashcards in Biochemistry Deck (255)
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91

NF1 vs. NF2 chromosome

NF1=17 (von Recklinghausen); NF2 = 22

92

von Hippel Lindau disease chromosome

del of VHL gene on ch 3p. AD disorder w/ cereballar hemangioblastomas, clear cell renal carcinomas, pheochromocytomas

93

Genetics of CF

Del of Phe508 on chromosome 7 (most common lucky number?)

94

CFTR function

ATP-using Cl- secretion in lungs and GI and Cl- absorption in sweat glands

95

X-linked recessive disorders

Be Wise, Fool's GOLD Heeds HOpe.
Bruton agammaglobulinemia, Wiskott-Aldrich, Fabry, G6PD, Ocular albinism, Lesch-Nyhan, Duchenne, Hunters syndrome, Hemophilias, Ornithine transcarbamylase deficiency

96

Duchenne defect and presentation

X-linked frameshift -> truncated dystrophin (DMD gene). Anchors muscle fibers (actin to transmembrane proteins); pelvic girdle weakness moves sup. pseudohypertrophy. < 5 yr onset; dilated cardiomyopathy

97

Becker defect

X-linked POINT mutation. onset in adolescence or early adulthood

98

Myotonic type 1 muscular dystrophy defect and presentation

CTG repeat expansion of DMPK gene; myotonia, m. wasting, frontal balding, cataracts, testicular astrophy, arrhythmia.

99

Fragile X defect and presentation

X-linked FMR1 gene w/ CGG (n=200) expansion leads to hypermethylation. Xtra large testes, LONG face with large jaw, large everted ears, autism. Short X -> Long face, large jaw, large testes, large ears.

100

Trinucleotide repeat expansion diseases

X-Gf's First Aid Helped Ace My Test; C_G (Community group!) Fragile X = cGg. Friedrich ataxia = gAa. HD = cAg. Myotonic dystrophy = cTg

101

1st and 2nd trimester Screen for Down's is?

1st: Increased nuchal translucency, hypo plastic nasal bone, serum PAPP-A down, free Beta-hcg up
2nd: quad screen; L alpha, Up beta, L estriol, Up inhibin

102

Edwards syndrome

E for election = chromosome 18. Severe ID, rocker-bottom feet, micrognathia, low-set ears. Death within 1 year. 1TM - low PAPP-A and free Beta. 2TM - L alpha, low Beta, low estriol, low A. Overriding fingers (2>3, 5>4)

103

Patau syndrome

P for puberty = chromsome 13. Severe ID, rocker-bottom, micropthalmia, microcephaly, celft liP/Palate, HOLOPROSencephaly, polydactyly. 1TM - Up Beta, low PAPP-A, increased nuchal translucency

104

Robertsonian translocation

Nonreciprocal of 13, 14, 15, 21, 22 where two q arms fuse, losing p arms. Balanced ok. Unbalanced palms.

105

Cri-du-chat syndrome

Microdeletion of short arm of chromosome 5. (A little high 5 for the cat.) Microcephaly, mod-sec ID, mewing, epicentral folds, VSD

106

Williams syndrome

Microdeletion on 7q (# Ivies - 1 = 7; Little ivy). Elfin facies, ID, hypercalcemia, good verbals, very friendly

107

CATCH-22

Cleft palate, Abnl facies, Thymic aplasia (T-cell def), Cardiac defects, Hypocalcemia (No C-cells!). 22q11. Abberant dvpt of branchial 3rd and 4th. diGeorge - thymic, parathyroid, . cardiac. Velocardiofacial - palate, facial, and cardiac

108

Fat soluble vitamins

Fat soluble - A, D, E, K. Very dependent on gut and pancreas for absorption. More likely to go toxic. KADE skywalker is fat.

109

Water soluble vitamins

B1,2,3,5,6,7,9,12.C. B deficiencies -> dermatitis, glossitis, diarrhea.

110

Excess Vit A?

Acute (n/v/vertigo), long (alopecia, HLD, HEPATO, PSEUDOTUMOR), teratogenic (microcephaly, cleft palate, cardiac)

111

Deficient Vit A?

Night blindness, dry, xerosis cutis, alopecia, corneal degen, immunosuppression, squamous metaplasia.

112

Vit A F(x)?

Antioxidant, visual pigment, DIFFerentiation, tx for measles.

113

Thiamine f(x)?

BIG 3 (alpha-ketoglutarate dehydrogenase, alpha-ketoacid dehydrogenase, pyruvate dehydrogenase) + transketolase (for HMP shunt)

114

Deficient Vit B1?

Impaired glucose breakdown -> highly aerobic tissue damage.
Wernicke-Korsakoff - confusion, opthalmoplegia, ataxia
Dry beriberi - polyneuritis, symmetrical muscle wasting
Wet beribi - dilated cardiomyopathy, edema
Measured in lab by dec. transketolase activity in RBC's

115

B2 f(x)?

Riboflavin. Part of flavins FAD and FMN req. for redox reactions.

116

Deficient B2?

Cheilosis and corneal vascularization

117

B3 f(x) and name?

Niacin. Derived from tryptophan. Makes NAD+. Impairs hepatic production of VLDL -> lower LDL. (Higher HDL)

118

Excess B3?

Facial flushing, hyperglycemia, hyperuricemia

119

Deficient B3?

glossitis, PELLAGRA - diarrhea, dementia, dermatits. Etios - hartnup disease, malignant carcinoid, INH

120

B5 f(x) and name?

Pantothenate. CoA and FA synthase.