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Flashcards in Biochem - Stuff Missed Deck (34):
1

Hartnup disease

results from niacin deficiency
- niacin deficiency may be due to loss of dietary tryptophan, resulting from defective intestinal and renal tubular absorption of amino acid

2

Niacin/Vitamin B3

synthesized from tryptophan
- tryptophan is an essential amino acid

3

Signs of Riboflavin deficiency

Chelosis Glossitis
Keratitis, Conjunctivitis,
Photophophoia
Lacrimation
Marked Corneal vascularization
Seborrheic dermatitis

4

Vitamin E

- aka tocopherol
- functions as scavenger of free radicals (antioxidant)

5

Signs of Vitamin E deficiency

myelopathy
neurologic dysfunction

6

Vitamin B2 (Riboflavin)

- form FMN and FAD to form enzymes for electron transport

7

Pyroxidine (Vitamin B2)

coenzyme for decarboxylation and transamination of amino acids

8

Deficiency of Pyroxidine

Anemia
Peripheral neuropathy
Dermatitis

9

Phenylketonuria

inborn deficiency of phenylalanine hydroxylase to metabolize phenylalanine.

- manifests developmental delay, mental retardation, mousy body odor, and fair skin coloring

10

Niemann-Pick disease

- AR
- deficiency in sphingomyelinase
- progressive neurodegenerative disease
- hepatosplenomegaly
- cherry red macula
- foamy macrophages filled with spingomyelin

11

Fabry's disease

- X-linked disease
- deficency in alpha-galactosidase A
- peripheral neuropathy of hands/feet
- angiokeratomas
- CV/renal disease
- accumulation of ceramide trihexosidase

12

Gaucher's disease-

- Autosomal recessive
- deficiency in GLUCOcerebrocisidase
-very common
- hepatosplenomegaly
- asceptic necrosis of femur
- Bone crises
- Gaucher cells (macrophages that look like crumpled tissue paper)

13

Tay-Sachs disease

- Autosomal recessive
- deficient in Hexosaminidase A
- accumulation of GM2 ganglioside
- progressive neurodegeneration
- developmental delay
- cherry red spot of macula
- lysosomes with onion skin
- NO HEPATOSPLENOMEGALY (vs. Niemann-Picks disease)

14

Krabbe's disease

- AR
- deficient in GALACTOcerebrocidase, leading to accumulation of galactocerebroside
- leads to peripheral neuropathy
- developmental delay
- optic atrophy
- globoid cells

15

Metachromatic leukodystrophy

- AR
- deficient in arylsulfatase A
- accumulation of Cerebroside sulfate
- central and peripheral demyelination with ataxia
- Dementia

16

Hurler's syndrome

- deficient in alpha-L-iduronidase
- accumulation of heparan sulfat, dermatan sulfate
- presents with developmental delay,
- gargoylism (abnormal facial features)
- corneal clouding
- hepatosplenomegaly

17

Hunter's syndrome

- deficient in Iduronate sulfatase
- Mild Hurler's sndrome (no corneal clouding)
- mild developmental delay
-

18

Acyclovir

- monophosphorylation of viral thymidine kinase is the first step in the active conversion of acyclovir to active stae
- more effective against HSV and VZV than CMV or EBV

19

Pituitary adenomas

- causs symptoms from mass effect
- produce endocrine disorders
- prolactinomas are most common
- excess prolactin causes amenorrhea and galactorrhea
- bitemporal heminopsia from compression of optic chiasm is common

20

Interferons

- produced by eukaryotic cells in response to viral infection
- act as cytokins on neighboring cells, to stimulate neighbors to produce antivural proteins that impair viral synthesis

21

Edwards Syndrome

- Trisomy 18
- presents as micrognathia, low set ears, rockerbottom feet
- clenched hands with index finger overring the middle finger and fifth finger overriding fourth finger

22

Patau Syndrome

- Trisomy 13
- presents as holoproscephapy
- microcepthaly
- polydactly and rocker bottom feet
- multiple facial abnormalities including cleft lip/cleft palat

23

Most common cause of pneumonia, otitis media, and meningitis in adults

S. pneumoniae
- appears as Gram positive lancet shaped cocci in pairs

24

Most common cause of bacteria in adults of all ages

S. peneuomoniae

25

Fragile X Syndrome

- defect in FMR1 gene on long arm of chromosome Z
- increased number of CGG trinucleotide repeats leads to hypermethylation of cytosine bases and gene activation
- leads to mental retardation, facial dysmorphism, macro orchidism

26

Chromosomal instability disorders

- Xeroderma pigmentosum
- Ataxia-telegientascia
- Fanconi's anemia
- Bloom syndrome

27

Lynch syndrome

associated with defect in DNA mismatch repair genes
- increased risk of hereditary non-polyposis cancer (HNPCC) and extraintestinal malignancies

28

Homocystinuria Findings

- Increased levels of homocysteine in urine
- Mental retardation
- Osteoporosis
- Tall stature
- Kyphosis
- Lens subluxation (downward and inward)
- Atherosclerosis (stroke and MI)

29

Homocystinuria

- autosomal recessive - comes in 3 forms:
- can result from cystathionine deficiency (tx with less MEt and increased methionine, B12 , and folate in diet)
- decreased affinity for cystathionine synthase for pyroxidase (increased B6)
- Homocysteine methyltransferase deficiency (*requires B12)

30

Maple syrup urine disease

- autosomal recessive
- blocked degradation of branched amino acids (Isoleucine, Leucine, Valine)
- alpha ketoacid dehydrogenase (b1)
- caused increased of serum alpha-ketoacids
- can cause severe CNS defects, mental retardation, and death
- urine smells like maple syrup

31

Hartnup disease

- autosomal recessive disorder
- defective neutral amino acid transporter on renal and intestinal epithelial cells
- causes tryptophan excretion in in urine and decreased absorption in gut
- can lead to pellagra
- associated with B6 deficiency

32

Alkaptonuria

congenital deficiency of homofentisic acid in degradative pathway of tyrosine to fumate
- autosomal recessive and benign
- Dark connective tissue, Brown pigmented sclera, black urine upon exposure to ait
- may have debilitating arthralgia ( Homocysteine not good for cartilage)

33

Listeria

- transmitted through contaminated food
- causes sepsis and meningitis in immunocompromised adults
- common cause of infantile meningitis
- grows well in cold temps
- gram positive but tumbling motility key feature

34

Aspergillosis

- neutropenic patients are at risk for Aspergillus fumigatus
- produces septate hypate with ACUTE V-shaped branching
- causes invasive aspergillosis (seen in immunosuppressed patients)
- aspergillomas (seen in TB, emphysema and sarcoid pts)
- allergic pulmonary aspergillosus (seen in asthma patients)