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aggressive behavior + mild symptoms of Hurler's syndrome (dev'l delay, gargoylism, airway obstruction, hepatosplenomegaly); heparan sulfate and dermatan sulfate accumulation

Hunter's syndrome (XR)


Hypoketotic hypoglycemia (+ weakness and hypotonia)

Carnitine deficiency: can't transport LCFAs into mitochondria, so get toxic accumulation in cytoplasm


how many kcal from 1 g protein, carb, fat?

1 g protein --> 4 kcal
1 g carb --> 4 kcal
1 g fat --> 9 kcal


LCAT = lecithin-cholesterol acyltransferase: what does it do?

takes cholesterol and puts it into HDL particles (catalyzes esterification of cholesterol)


CETP = cholesterol ester transfer protein: what does it do?

allows HDL to deposit cholesterol into LDL, etc.. (mediates transfer of cholesterol esters to other lipoprotein particles)


Apolipoprotein E

mediates VLDL and chylomicron remanant uptake by liver cells


Apolipoprotein A1

activates LCAT (for cholesterol esterification)


Apolipoprotein C-11

lipoprotein lipase cofactor (LPL --> degrades TG circulating in chylomicrons and VLDLs)


apolipoprotein B-48

mediates chylomicron secretion by the intestine and chylomicron assembly


Apolipoprotein B-100

binds LDL receptor (LDL particle uptake by extrahepatic cells)


familial dyslipidemia with increased chylomicrons, increased blood TG and cholesterol; pancreatitis, xanthomas...

type 1: hyper-chylomicronemia
-no increase risk for atherosclerosis


familial dyslipidemia with increased LDL; atherosclerosis, Achilles xanthomas, corneal arcus; elevated blood cholesterol

type IIa - familial hypercholesterolemia
-aut dominant
-MI by age 20 if homozygous


familial dyslipidemia with increased VLDL; increased blood TGS; pancreatitis

type IV - hypertriglyceridemia
-have hepatic overproduction of VLDL


deficiencies in apo-B100 and apo-B48; FTT, steatorrhea, acanthocytosis, ataxia, night blindness

abetalipoproteinemia --> can't synthesize lipoproteins b/c no apob100 and apob48
-autosomal recessive
-accumulation within enterocytes because can't export absorbed lipid as chylomicrons


facial lesions (adenoma sebaceum), hypopigmented ash-leaf spots, coritcal and retinal hamartomas, seizures, MR, renal cysts, renal angiomyolipomas, cardiac rhabdomyomas, increased incidence of astrocytomas

Tuberous Sclerosis (variable presentations)


3 mitochondrial disorders:
-Leber hereditary optic neuropathy
-myotonic epilepsy

1) Leber Hereditary optic neuropathy --> bilateral vision loss
2) Myoclonic epilepsy with ragged red fibers --> myoclonus, seizures, myopathy assoc with exercise; irregularly shaped muscle fibers on skeletal muscle biopsy
3) MELA = mitochondrial encephalomyopathy with lactic acidosis and stroke like episodes--> seizures, stroke-like episodes with neuro-deficit, muscle weakness, increased serum lactate post-exercise and at rest


Hypoglycemia after prolonged fasting, with inappropriately low levels of ketone bodies: What enzyme is deficient?

Impaired Beta-oxidateion/Degradation of Fatty Acids; Acyl-CoA dehydrogenase deficiency


antibodies against collagen type 4?

=anti-glomerular basement membrane antibodies --> Goodpasture's syndrome! (hemoptysis + oliguria)...


recurrent nosebleeds, and pink spider-like lesions on oral and nasal mucosa, face, and arms.

Osler-Weber-Rendu syndrome = hereditary hemorrhagic telangiectasia


How are sugars attached to nitrogen-containing bases in nucleotides?

N-glycosidic bonds
(between sugars-->hydrogen bonds; between nucleotides-->phosphodiester bonds)


Which step in collagen synthesis is impaired in pts with scruvy?

Hydroxylation of specific proline and lysine residues on the pro-alpha collagen


How does ethanol metabolism contriute to hypoglycemia?

increases NADH/NAD ratio in liver --> so, causes:
*pyruvate--> lactate
*OAA--> malate

***So, inhibits gluconeogenesis and stimulates hepatic fatty change
***So, get overproduction of lactate-->acidosis; also overproduction of NADPH-->increased fatty acid synthesis


What mechanism allows for the production of more than one protein by one human gene?

Alternative splicing