Biochemistry Flashcards
1
Q
Major cause of AR SCID
A
Def of adenosine deaminase
2
Q
Lesch Nyhan Syndrome
A
Gout, angry, MR, self mutilation, orange sand in diaper
Tx: allopurinol or febuxostat
3
Q
What is defective in xeroderma pigmentosum?
A
Nucleotide excision repair - can’t fix pyrimidine dimers from UV light - in G1 phase
= increased risk skin CA
4
Q
What is defective in Lynch syndrome?
A
Mismatch repair in G2 phase
5
Q
What is mutated in ataxia telangiectasia?
A
Nonhomologous end joining to fix ds breaks
6
Q
What blocks 30S protein synthesis?
A
Aminoglycosides
Tetracyclines - block from getting to A site
7
Q
What drugs prevent protein synthesis at 50S?
A
Clindamycin Macrolides Streptogranines Chrolamphenicol Linezolid
8
Q
GFAP
A
Stains for neuroglia
Good for astrocytoma, glioblastoma
9
Q
Desmin
A
Stains muscle
Good for tumors - rhabdomyosarcoma
10
Q
Drugs that work on microtubules
A
Mebendazole - anti helminth Griseofulvin - antifungal Colchicine - gout Vincristine/Vinblastine - CA Paclitaxel - CA
11
Q
Type I collagen
A
Bone, skin, tendon
12
Q
Type II collagen
A
Cartilage
13
Q
Type III collagen
A
Reticulin - skin, blood vessels, fetal, granulation
– Ehlers Danlos
14
Q
Type IV collagen
A
Basement membrane
- targeted by autoabs in Goodpasture
- Alport syn
15
Q
Defective in Ehlers Danlos?
A
Type III Collagen
16
Q
Defective in Alport syndrome?
A
Type IV collagen
17
Q
Mut in ALS?
A
SOD1
Superoxide dismutase
18
Q
Brushfield spots
A
Downs - while fibrotic speckles on iris
19
Q
Downs associations:
A
Hirschsprung Duodenal atresia Early Alzheimer's CA - baby AML CA - 3-7 y ALL Quad screen: all down except hi -decreased aFP, estriol - increased B-hcg, inhibin A
20
Q
Trisomy 18
A
Edward - Edward Cullen stuck at 18
Horseshoe kidney, rocker bottom feet, overlap fingers
Quad screen - all 4 decreased
21
Q
Trisomy 13
A
Patau - 1 and 3 on side - extra finger and cleft lip
holoprosencephaly
22
Q
Cri du chat
A
5 little short cats with small heads crying over a broken heart
Deletion short arm of chr 5, hypo plastic larynx
VSD mc
23
Q
Klinefelters
A
Inc. FSH, LH Dec. T guys are kinky, too much seX Osteoporisis Increased risk BCA, testicular CA
24
Q
4 causes of Hydrops Fetalis
A
Parvo B19
Rh- incomp
a-Thal
Turner syn
25
Turners
Shorty missing x - Shox - homeobox gene
| cystic hygroma - web neck
26
Tay Sachs
Tay is 15 yrs old, walking through the woods - takes cherries and throws through the window of an old house. witch comes out, reaches into sach and puts a hex on him. Only 2 cars, 2 GM cars.
Def of hexosaminodase A, accumulates GM2 ganglioside
EM: distended lysosomes with whorls (like car wheel)
Retina - cherry red spot
27
Niemann Pick
Neimann picks his nose and sphings it at a zebra with stripes
Def in sphingomyelinase, sphingomyelin accumulates - brain, retina, Macrophages = big organs
Chr 11 that look like stripes on zebra
28
Gaucher dz
```
MC
Chr 1
Def of glucocerebrosidase, glucocerebroside accumulates - Macro
Gaucher cell - sinusoids filled with RBC
Bone - erlenmeyer flask deformity
```
29
Erlenmeyer bones
Gaucher dz
| Osteopetrosis
30
Pompe Dz
Glycogen in lysosome - PAS+
a-1-a4-glucosidase
aka acid maltose
31
Mucopolysaccharidosis
GAGs accumulate --> HS, DS, CS (chondroiton sulfate)
1st in macro -> HSM, fibroblasts accumulate = cloudy cornea
MC: Hurler
Hunter
32
Hurler dz
Hurling is worse than hunting
Spiderman villan Gargoyle throwing pumpkins full of PAS+
Misses spiderman = cloudy body - cornea, bone abnl, CTS
rides away on a mucopolysacchaRIDE
HSM, cloudy cornea, arthritis, gargoyle, CTS, heart valve probs
33
Hunter dz
Male, x-linked mild compared to hurler
34
Osteogenesis imperfecta genetic mut?
Type 2:
most severe, pulm hypoplasia, hearing loss, blue sclera
Mut: COL1A1, COL1A2
35
Marfan syndrome
Defect in fibrillin - glycoprotein that forms sheath around elastin
Subluxation of lenses
36
Pleiotropy
One gene contributes to multiple phenotypic effects
| ex, PKU
37
Incomplete penetrance
Not all with it, show phenotype
| ex, BRCA1 - not always CA
38
Codominance
Both alleles contribute -
| ex, blood groups, a1-antitrypsin
39
Prader Willi
Chr 15 paternal gene is deleted/mutated
| hyperphagia, obesity, MR, hypogonadism
40
Angelman Syn
Angels miss their moms
Chr 15 maternal gene deleted/mutated
Inappropriate laughter, seizures, ataxia, severe MR
41
Ex of X-linked dominant
Hypophoshpatemic rickets, Rett syn, fragile X, Alport
42
Mut in achondroplasia
FGFR3 - inhibits chondrocyte proliferation
43
Li Fraumeni Syn
abnl in TP53
| Malignancies at young age - sarcoma, breast, leukemia, adrenal glands
44
MEN 2A and 2B gene?
RET
45
Neurofibromatosis genes?
NF1 - chr 17
| NF2 - chr 22
46
CF deletion?
deletion of Phe508
defect in CFTR gene on chr 7
Infections: Pseudomonas, s. aureus, chronic bronchitis
Meconium ileus in newborns, infertility in males, nasal polyps
47
X linked recessive D/O
```
Fabry dz
Wiskott-Aldrich
Ocular albinism
G6PD def
Hunter syn
Bruton agammaglobinemia
Hemo A and B
Lesch-Nyhan
Duchenne (Beckers)
```
48
Duchenne mut?
XL frameshift mutation of dystrophin protein
| vs. Beckers is non-frameshift insertion
49
Fragile X
Big balls, jaws and ears
Trinucleotide of CGG in FMR1 gene
MVP
50
22q11 deletion syndromes
DiGeorge - thymic, parathyroid, cardiac
Velocardiofacial syn - palate, face, cardiac
3rd and 4th pouches
51
Vit A
Retinol
bumping into things at noc b/c lights go down and rods come out at night
squamous metaplasia - scaly skin, corneal degeneration, Bitot spots
Tx of AML M3 - all-trans retinoic acid
52
Vit B1
Thiamine
Important to glucose breakdown
Seen in malnutrition and alcoholism
Wernicke-Korsakoff syn
53
Dry beriberi
Def of Vit B1 thiamine - nerves, sym m wasting
54
Wet beriberi
Def of Vit B1 thiamine - high output cardiac failure
55
Vit B3
```
Niacin - 3 vowels
4 D's - Pellagra
D - dermatitis
D - dementia
D - diarrhea
D - death
```
56
Excess Niacin
Facial flushing - prostaglandins
| Pretx with ASA
57
Def of Vit B6
Pyridoxine
| convulsions, hyperirritability, peripheral neuro
58
Isoniazid can lead to?
Dev vit B6 - pyridoxine
59
Vit B9 aka?
Folate
60
drugs that can cause folate def?
Phenytoin, sulfonamides, methotrexate
61
Common causes of Vit B12 def?
Malabsorption - celiac's, enteritis, diphyllobothrium
Lack of IF - pernicious anemia, gastric bypass
Absence of terminal ileum - crohn
62
what vit can look like B12 def?
Vit E - is an antioxidant that protects RBC and membranes from ROS
Hemo anemia, neuro
63
Kwashiorkor
Protein malnutrition
| liver fatty change, m wasting, edema
64
Marasmus
Total calorie malnutrition
| emaciation
65
what drug if taken and then drinking can have disulfram like effects?
Metronidazole
66
Fomepizole
Inhibits alcohol dehydrogenase
| Used for antidote to methanol or ethylene glycol poisoning
67
Garlic breath?
Arsenic poisoning
68
G6PD Def
Decreased NADPH -> hemolytic anemia
XLR - inc malarial resistance
Heinz bodies - denatured Hb ppts
Bite cells - Macro bite into the Heinz ketchup bodies
69
Assoc with G6PD Def?
```
Sulfonamides
Primaquine
Nitrofurantoin
Isoniazid
Fava beans
Dapsone
Chlorquine
```
70
Essential fructosuria
defect in fructokinase, asx, fructose in blood and urine
71
Fructose intolerance
Def of aldolase B
| Fructose-1-phosphate accumulates
72
Galactokinase def
can get infantile cataracts
73
Tryptophan derivative
B6 --> niacin --> VAD
| Serotonin --> Melationin
74
Glycine derivative
Porphyrin --> heme
75
Glutamate derivative
GABA - inhibit
| Glutathione - antioxidant
76
Arginine derivative
Creatine
Urea
NO - vasodilation
77
PKU def of what 2 things?
MC: phenylalanine hydrolase
| tetrahydrobiopterin cofactor
78
Maple syrup urine dz
Blocked degradation of branched AA - LIV
L - leucine
I - isoleucine
V - baline
79
Alkaptonuria
Dark like Al Capone
can't degrade tyrosine
Def of homgentisate oxidase
Urine black - black/blue CT and sclera
