Term
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Definition
| loss of HGPRTase activity. leads to gout, severe mental retardation, and a tendency for self-mutilation (biting of the hands and lips). Allopurinol reverses the buildup of urate found in these patients, but does not alter the neurological defects |
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Term
| Two drugs used to treat Gout |
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Definition
Colchicine: blocks microtubule synthesis but works here by blocking inflamation.
Allopurinol: a suicide inhibitor of xanthine oxidase |
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Term
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Definition
| 5-phosphoribosyl-1-pyrophosphate: reacts with hypoxanthine and xanthine in the purine salvage pathway and is involved in the committed step of de nova synthesis of purines through formation of 5-phosphoribosylamine |
|
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Term
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Definition
| hypoxanthine-guanine phosphoribosyl transferase: enzyme that salvages hypoxanthine and xanthine by reaction with PRPP |
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Term
| Cause and mechanism of SCID |
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Definition
Cause: lack of adenosine deaminase or a lack of purine nucleoside phosphorylase causes T-cell dysfunction
Mechanism: build up of dATP
potentially inhibiting production of all dNDPs by ribonucleoside diphosphate reductase blocking DNA replication. |
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Term
| How does alcohol lead to gouty attacks |
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Definition
| It causes increased breakdown of hepatic ATP |
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Term
| common intermediate in pyrimidine sythesis |
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Definition
|
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Term
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Definition
| cofactor of methionine synthase, converts homocysteine to methionine. The only other human enzyme requiring B12 converts methylmalonyl CoA to succinyl CoA and is involved in odd-chain length fatty acid degradation and branch-chain amino acid degradation |
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Term
| B12 deficiency results in elevated what in the blood? |
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Definition
|
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Term
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Definition
enzyme involved in
regenerating tetrahydrofolate, while synthesizing methionine. Requires B12 as a cofactor |
|
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Term
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Definition
| required for B12 absorption in the ileum. |
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Term
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Definition
| B12 defiency due to lack of intrinsic factor |
|
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Term
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Definition
neurologic dysfunction (numbness,
spastic gait, confusion and dementia) likely resulting from SAM S-adenosylmethionine defiency and megaloblastic anemia (can be masked by excess folate) |
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Term
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Definition
| analog of guanosine in which the ribose ring is disrupted. Normal cells will not scavenge this analog, but the thymidylate kinase produced by herpesviruses will act on it. |
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Term
| Which base can be synthesized as the free base? |
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Definition
|
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Term
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Definition
| ribonucleoside diphosphate reductase. Converts NDPs to deoxyNDPs |
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Term
| 5-Fluorouridine (administered as Adrucil, Efudex, or Fluracil) |
|
Definition
| converted by salvage pathway to 5-fluorodeoxyuridylate (F-dUMP. Suicide inhibitor of thymidylate synthase, blocks dTMP production |
|
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Term
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Definition
competitive inhibitor of dihydrofolate reductase (DHFR) and therefore also
blocks dTMP production |
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Term
| Sulfonamides (or sulfa drugs) |
|
Definition
| antibacterials that compete with paraaminobenzoate in the synthesis of folates in bacteria |
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Term
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Definition
| converts orotidine monophosphate (OMP) to uridine monophosphate (UMP) by liberating carbon dioxide. It is known for being an extraordinarily efficient catalyst |
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Term
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Definition
| Target of methotrexate. First enzyme involved in regenerating tetrahydrofolate to be used by thymidylate synthase. |
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Term
| Role of Glutamine in acidosis |
|
Definition
| Urea cycle decreases, liver glutamine output increases, kidneys take up glutamine and break it down to PEP which is used for gluconeogenesis releasing 2 CO2 and 2 NH3. HCO3- and glucose are released into the blood, protons and NH3 become NH4+ which is excreted in the urine. |
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Term
| Under acidosis what are bicarbonate levels relative to normal? |
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Definition
|
|
Term
|
Definition
| Elevated anion gap is a sign of acidosis usually caused by an increase in unmeasured anions. Its calculated by subtracting the combined Cl- and bicarb/CO2 concentrations from the Na concentration |
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Term
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Definition
| Urea cycle, ketone synthesis, fructose catabolism, bile production and bilirubin conjugation, serum protein sythesis |
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Term
| Why do you see an increase in nonesterfied fatty acids in the blood when you have liver damage? |
|
Definition
| Decreased gluconeogenisis leads to less insulin signaling so more is released from adipocytes. Also less is taken up by the liver due to the damage. |
|
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Term
| High Liver NADH leads to increased what? What decreases? |
|
Definition
Increase: Lactic acid, VLDL TG and ketone synthesis. Also hyperuricemia
Decreased: gluconeogenesis, and fatty acid oxidation |
|
|
Term
| Alcohol tolerance is caused by an upregulation of what? |
|
Definition
| Cytochrome P450 that is able to oxidize ethanol |
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Term
| Mechanism of hemochromatosis |
|
Definition
| Liver is underexpressing Hepcidin |
|
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Term
|
Definition
| S-Adenosyl methionine coenzyme involved in methyl group transfers |
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Term
|
Definition
| defensin. secreted from liver. binds ferroportin and causes it to be internalized and degraded. Expression is increased when iron is high or inflammation. decreased when there is anemia or hypoxia. |
|
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Term
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Definition
| Oxidizes Iron to +3 so it can be bound by transferrin in the plasma. Macrophages have a GPI linked ceruloplasmin |
|
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Term
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Definition
| linked to the basal surface of enterocytes. Oxidizes Iron to +3 so it can be bound by transferrin |
|
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Term
|
Definition
| Ferroportin is a transmembrane protein that transports iron II from the inside of a cell to the outside of it. It is inhibited by hepcidin causing Iron buildup in enterocytes and macrophages |
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Term
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Definition
| causes hemochromatosis if mutated |
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Term
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Definition
| tumor suppressor that halts cell in G2 |
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Term
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Definition
| Tumor supressors that stop cells in the S phase |
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Term
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Definition
| make cyclins ineffective until they achieve a high concentration. INK4 during G1. Cip/Kip |
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Term
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Definition
|
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Term
|
Definition
| altering the behavior of Cdks, cyclins, and Cdk inhibitors |
|
|
Term
| caffeine and checkpoint control |
|
Definition
| stops the checkpoint control that occurs during G2 |
|
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Term
anaphase promoting complex
(APC) |
|
Definition
responsible for determining when the spindle is complete, then triggering
the dissolution of the chromatid glues that cause anaphase. |
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Term
|
Definition
|
|
Term
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Definition
| promotes proliferation. kinase that integrates information from several sources, including a number of tumor suppressor proteins, and is thought to be one of the main sites of integration of information concerning nutrient availability. |
|
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Term
|
Definition
| All cells have apoptosis as the default action. They are alive only because they are bathed in signals (like IGF and IL-3) telling them not to do it. |
|
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Term
| FasL or tumor necrosis factor/TNF |
|
Definition
| External apoptosis initiation signals. This form of signaling is especially important during the immune response when a cell harboring a pathogen is instructed to die to kill the pathogen. |
|
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Term
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Definition
| pro-survival (anti-apoptotic) protein. Binds to BAX BID/BAD which would otherwise allow cytochrome C to be released from the mitochondria thus initiating apoptosis. Bcl-2 binding to Apaf-1 directly also prevents apoptosis because it blocks it from binding cyctochrome c |
|
|
Term
| characteristic tests for apoptosis |
|
Definition
flow cytometry: less than 2C DNA content
Agarose Gel: 200 bp latters of DNA (cut at nucleosomes)
TUNEL: Terminal dNTP transferase BrdU
nicked end labeling. number of ends for labeling is greatly increased |
|
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Term
|
Definition
| always face cytosol except during apoptosis PS molecules flip to the outer leaflet where they are recognized by PSspecific receptors on phagocytes. |
|
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Term
|
Definition
| serves as a chemotactic signal for macrophage recruitment during apoptosis |
|
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Term
|
Definition
| Promotes Apoptosis. If its converted to Sphingomyelin than DAG is formed which promotes cell proliferation. |
|
|
Term
| sphingosine-1 phosphate (S1P) |
|
Definition
| Metabolite of ceramide. Promotes growth and angiogenisis. lymphocytes exit from lymphoid tissues into blood or lymph in response to S1P gradients |
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|
Term
| Phosphoinositides role in bacterial invasion. |
|
Definition
| Some bacteria are able todo things that change the phosphate arrangements on Phosphoinositides which cause rearrangments of cytoskeleton and allow endocytosis |
|
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Term
|
Definition
| Important in growth factor signaling, membrane specification, endocytosis and bacterial invasion. Variation in phosphate position on the head group specifies function |
|
|
Term
| Prpc prion disease infectivity |
|
Definition
| Must be on a GIP anchor that allows rapid diffusion and allows it to jump from one cell to another |
|
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Term
|
Definition
| at the start of synthesizing eicosinoids PA2 first cuts Arachidonic acid from the plasma membrane |
|
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Term
|
Definition
| adds 4 oxygens and puts a ring into AA to produces prostaglandins and thromboxanes(cause platelet aggregation). Target of NSAIDS |
|
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Term
|
Definition
| yields the leukotrienes, HETEs, and lipoxins. Does not put a ring in. Important in asthma |
|
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Term
|
Definition
| targets Ca channels in neurons |
|
|
Term
| Platelet activating factor |
|
Definition
| plasmalogen, ether linked at C1, activates platelets neutrophils and monocytes. Causes leukocytes to adhere and migrate through endothelium. |
|
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Term
|
Definition
| involved in the esterfication of cholesterol. LCAT is in blood and involved with HDLs. ACAT is in cells that store cholesterol for sythesis of steroid hormones. |
|
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Term
|
Definition
| Enzyme involved in steroid hormone synthesis. Target for drugs that want to prevent ER+ breast cancers |
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Term
|
Definition
| Bile acid sensor in enterhepatic system. Low affinity ligand, feedforward regulation. |
|
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Term
|
Definition
| Cholesterol sensor, governs transport, catabolism and elimination of cholesterol. Associated wth Tangier disease and sitosterolemia. |
|
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Term
|
Definition
| involved in fatty acid catabolism |
|
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Term
|
Definition
| promotes fat storage by increasing adipocyte differentiation and transcritpion of lipogenic factors |
|
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Term
|
Definition
| LCAT cofactor, structural |
|
|
Term
|
Definition
| lipoprotein lipase cofactor |
|
|
Term
|
Definition
| receptor recognition. involved in retrieval of HDL, VLDL and Chylomicrons |
|
|
Term
| Cholesterol Ester Transfer Protein (CETP) |
|
Definition
| catalyzes the transfer of CE from HDL to apo B-containing lipoproteins such as VLDL and LDL |
|
|
Term
|
Definition
| pumps cholesterol onto HDL particles from peripherial cells. Deficiency leads to tangiers disease, no HDLs |
|
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Term
|
Definition
| the really bad cholesterol |
|
|
Term
|
Definition
| Poor clinical outcome of Alzheimer strokes and other trauma. ApoE3 is the better form(doesn't form a stable bridge) |
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