Biochem, Congenital Conditions, and Cancers Flashcards
Retinoblastoma
Loss of Rb, allowing for E2F to activate transcription Autodominant, sporadic/familial
Patient has familial history of osteosarcoma, rhadbomyosarcoma, breast, and brain cancer. Condition? Mechanism?
Li-Fraumeni Syndrome: Loss of hetero of p53; AUTODOMINANT
Chromosome 17
Familial Adenomatous Polyposis
APC w/t makes a destruction complex for Beta catenin thus silencing the Wnt pathway. Loss of gatekeeper causes hyperactivation of Wnt pathway think APC is an army transport for the beta catenin (swords are in army)
Von Hippel Lindau Syndome
Loss of VHL protein which normally targets Hypoxia Inducible Factor 1alpha for ubiquination and degredation. Loss causes Increased HIF levels vHippel L increases HIF levels Risk for Hemanigioblastomas of Cb, Pheos, Renal cell carcinoma (clear cell)
Hereditary non-polyposis colonrectal cancer
Lynch Syndrome due to loss of DNA mismatch repair
Wilms tumor on chromo?
WT-1 on Chromo 11
MEN 1, 2a, 2b
MEN 1: OM3p–Pituitary (prolactin/ACTH), parathyroid, pancreas (panc is a GASTRIN secreting tumor***)
MEN2a: 1M2P–medullary thryoid cancer (calcitonin), pheo, parathyroid
MEN2b: 2M1P–Medullary thryoid (calcitonin), mucosal neuramata (oral), pheo, Marfan like body (tall–abraham lincoln)
Carcinomas that spread hematogenously
Renal Cell Carcinoma, Follicular Thyroid Carcinoma, Hepatocellular Carcinoma, Choriocarcinomas
Standard Deviation
1 STD
2 STD
3 STD
1) 68
2) 95 (+27 each side)
3) 99.7 (+4.5)
Hartnup’s Disease: mechanism? deficient in? symptoms?
Defective renal/GI absorption of Tryptophan: need for Melanin (hypopigmentation/sunburn), nicotininc acid (Pellagra from niacin def) and serotonin.
Patient will have aminoaciduria of neutral amino acids
Stains:
Vimentin?
Desmin?
1) Connective Tissue
2) Muscle
Cofactor needed for Transketolase?
Transaminase?
Thiamine (B1)
Pyridoxine (B6)
Which AA donates NH3 in urea cycle?
What starts cycle?
What is rate limiting enzyme?
Aspartate
N-acetyl glutamate
Carbamoyl Phosphate Synthase I
Diaper Smelling like burnt sugar
Maple Syrup Urine Disease: cannot break down branched chain AA (leucine, isoleucine, valine).
Broken Branched chain alpha ketoacid dehydrogenase def, pyruvate dehydrogenase, alpha ketoglutarate dehydrogenase.
Cofactors: TLCFN (“Tender love and care for no-one)
Thiamine, Lipoate, CoA, FAD, NAD+
Co factors required for branched chain AA degradation
Complex: branched chain alpha ketoacid dehydrogenase.
Cofactors: Tender loving care for Nanny
Thiamine, Lipoate, CoEnzyme A, FAD, NAD
Enzyme needed to make Serotonin?
Cofactor? Cofacor produced by? What else is it used in?
Tryptophan hydroxylase (requiring BH4 made by Tetrahydrobiopterin reductase)
Taking Phenylalanine to Tyrosine and then to DOPA
Tetrahydrobiopterin enzyme used to make?
Whihc is used in?
BH4
Dopa, Tyrosine, Serotonin, and NO
Enzyme that converts procarcinogens into carcinogens?
Microsomal Monoxygenase
(can be Bilateral) renal tumors of blood vessels, muscle, and fat: Condition? Associated with what else?
TSC: Autodominant.
Bilateral renal Angiomyolipoma, Brain Harmatomas (causing seizures/mental retardation), and ash leaf skin patches
Cerebellar Hemangiomas and Liver Cysts: condition?
Associated with what else?
von Hippau Lindau (defect in vhl protein that inhibits HIF)
Bilateral renal cell carinoma
Capillary Angiomas of the face and choriod?
Sturge Weber Syndrome. “weber wine”
Facial port wine stain and leptomeningeal capillary-venous malformations.
Multiple telangectasia of mucosa and skin?
Hereditary hemorrhagic telangectasias (Osler-Rendu-Weber).
Recurrent epistaxis and GI bleeding (melena)
Zero Order kinetics?
First Order Kinetics?
Zero Order=same amount of drug (ie 10mg)–occurs when removal system is saturated
First order= proportion of drug (ie 50%)–usually is linear on graph and tends to occur before clearance is saturated
Dark Connective Tissue with brown pigmented sclerae, urine turns black with prolonged exposure to air: Cause? Enzyme? Other findings?
Alkaptonuria (ochronosis): def of homogentisate oxidase.
Can’t degrade tyrosine to fumarte.
Can have debilitating Arthalgias (homogenitistic acid is toxic to cartilage)
Riboflavin (B3) is a cofactor for?
FMN and FAD which are used in the TCA cycle.
FAD is used for Succinate dehydrogenase which takes succinate to fumarate
Non Insulin Dependent Glut’s? Location?
Liver/Panc cells?
Skeletal Muscle?
Glut 1/3 in brain
Glut2
Glut4 (insulin dependent)
Clinical Consequence of a glycolytic enzyme def?
Hemolytic Anemia (pyruvate kinase def)
Rate limiting enzyme for:
- Glycolysis
- Gluconeogenesis
- TCA
- Urea Cycle
- De novo purine
- De novo pyrimdine
- PFK1
- Fructose 1,6 bisphosphatase
- Isocitrate dehydrogenase
- Carbamoyl Phosphate synthase I
- PRPP (glutamine phosphoribosylpyrophate amidotransferase)
- Carbamoyl Phosphate Synthase II
Cori Cycle?
Lactic acid produced by muscles goes into blood and goes thru gluconeogenesis to get to turned into glucose (pyruvate is intermediate in both muscles and liver)
Pyruvated Dehydrogenase Complex cofactors?
TLC for noone.
“Thiamine (B1), Lipoic Acid, CoA (from B5), FAD (B2), NAD (B3)”
Which cell cannot use Ketones? Why?
RBCs cannot use Ketones because they lack MITOs
(Brain can use Ketones)
Newborn with anion gap ketoacidosis and hypoglycemia with increased propionic acid in urine?
Congential Propionyl CoA carboxylase deficiency (same thing inhibited with B7 def from too many egg whites=Dermatitis, allopecia, Enteritis)
Propionyl CoA–>Methylmalonyl CoA (via P CoA carb w/ Biotin)
Weakness, Lethargy, Hypoketotic Hypoglycemia:
Deficiency? What builds up?
Most likely Carnitine Acyl Transferase Deficiency (Fatty acid metabolism).
Long chain fatty acids from inability to bring long chain fatty acids into mitochondria