Week 2 Enzymes and Proteins

1. What are enzymes?    Enzymes are protein catalysts of biological origin.2. How do enzymes work? Enzymes work by decreasing amount of free energy of activation necessary.3. What is an international unit? The amount of enzyme activity that catalyzes the conversion of one micro mole of substrate per minute under the specified conditions of the assay method.4. What effect does temperature have on enzymes?  Temperature can increase an enzymatic rxn.5.  At what temperature can enzymes be run?  How will different temperatures temperatures affect your results? Best temps at 37 c or 30 w/ + or - 1c.  Different temps can inactivate or denature the enzymes reaction. 6. How do enzymes accelerate the rxn  rates? It decreases the amount of free energy of activation necessary.7.  What does an increase and decrease in enyme levels indicate? elevated levels= tissue damage and necrosisZero Order Kinetics-dependent on enzyme activity and independent of substrate concentration-substrate is in excess-rate of rxn is constant w time and dependent only on concentration of enzyme in system^ CPK - increase early primary acute MI - catalyzes the phosphorylation of creatine by ATP - found mainly in skeletal and cardiac muscle and in brain tissue8. Disorders associated w elevated CK, ALT, AST, GGTP, Alk Phos?^CPK -CVA (cerebral vascular incident)-Hypothyroidism- Intramuscular Injection- Skeletal Muscle disease^ALKP-increase in obstructive jaundice -increase in 3rd trimester of pregnancy - increase Pagets Disease (Osteitis deformans)* normal in teens^GGTP-present in almost all cells of the body -increase in liver in some pancreatic disorders-increase in chronic alcoholism9.  What substrates act on AST and ALT?ALT=alanine and alpha-ketoglutarateAST=aspertate10 

1.  What are the three enzymes most associated w an MI?  CPK, AST and LDH2.  Which of these enzymes is most sensitive for the diagnosis of MI? CPK3.  When do these enzymes increase and decrease?CPK= increase in disorders like cerebral vascular accident, hypothyroidism, skeletal muscle disease and intramuscular injection AST=LDH=4.  Rxns these enzymes catalase?

3.  Given amylase and lipase, what substrates do they act on? Amylase= starch Lipase_triglycerides5.  Most common cause of pancreitis?   alcohol abuse which increases lipase and amylase levelsLipase Reaction  TG--> Glycerol+ free fatty acids 

1.  elevated protein could mean? meningitis, encephalitis, cerebral vascular accident, brain tumor and MS2. What condition would there be an expected increased level of serum albumin? dehydration 3.  What is useful in early stages of glomerular dysfunction? Microalbumin 4.  Characteristics of cardiac troponin (cTnI) as it relates to AMI? TNI is detectable 4-6 hours after onset of chest pain, reaches peak concentration at 12 hrs and can remain high for 3-10 days after MI5.  In a healthy person what protein fraction has the greatest concentration in serum? Albumin then IgG6.  What plasma protein does liver manufacture?  Albumin- haptoglobin-fibrinogen 7.  Which Immunoglobulin class characterized by its posession of a secretory component, is found in the saliva, tears and body secretions? IgA8.  Which immunoglobulin is able to cross the placenta from the mother to the fetus? IgG 9.  What is the acute phase reactant protein that is able to inhibit enzymatic proteolysis and has the highest concentration of any of the plasma preolytic inhibitors? AA- alpha antitrypsin 10.  Which protein is normally produced by the fetus, but found in increased amounts in the amniotic fluid in cases of spina bifida? AFP 11.  Technique used to quantify specific immunoglobulin classes? EIA, nephelotometry, turbidimetry12.  What is associated w carcioembryonic antigen? CEA- tumor marker for colorectal, GI, lung and breast carcinoma 13. In cases of hepatoma, which protein not normally found in adult serum is synthesized by liver cells? AFP14.  Characteristics of prostate specific antigen? PSA- tumor marker       -single chain glycoprotein        -serum quantified using immunoassays       15. Oncofetal antigen that is elevated in nonmucinous epithelial ovarian cancer? CA125- increased in ovarian cancer16.  Asialyated lewis blood group antigen associated w colorectal carcinoma? CA19-9- increased in colorectal carninoma 17.  elevations of serum levels of alpha-fetoprotein is associated w? -testicular germ cell tumor  -pancreatic carcinoma -gastric carcinoma - hepatocellular carninoma (hepatoma)18.  Whats associated w chronic gonadotropin?  elevated BHCG- confirms pregnancy                          -tumor marker for testicular cancer                         - Beta subunit confers immunogenic specificity19.  What tumor markers are elevated in more advanced stages of breast cancer? CA15-3, CA54920.  "Big 4" malignancies of cancer? -lung, colon, breast and prostate 21.  leading cause of death cancer in men and woman? lung cancer22.  What is a tumor marker? lab test used in cancer detection, diagnosis and monitoring23.  Phases of cancer? -induction, in site, invasion and dissemination 24. what phase in cancer may last 30 yrs or longer ? induction 25.  during dissemination the common sites of distant metastases are? lung, liver and bone 26.  Ideal tumor marker criteria? - serum level reflects tumor burden - precedes and predicts cancer before they are clinically detectable - levels not subject to "wild fluctuations" unrelated to progress of cancer 27.  when establishing decision threshold for tumor marker, lowering  decision level will improve what ?  -dignostic sensitivity and generate increased false positive results 28.  What are the major roles for tumor markers in managing patients w potential or actual malignancy? -assessment of potential cancer risk -confirm the patient has cancer  -staging a cancer 29.  examples of tumor markers used for managing patients with cancer? CEA, PSA, AFP, CA125 30.  Primary application of CEA ? Colon 31.  what is CA125 useful for diagnosing? ovarian cancer32.  Most commonly diagnosed cancer among older men in the US? prostate 33. what has been attributed to increased incedence of prostate cancer? -Inensive screening efforts- aging of population- heightened public awareness34.  Commonly diagnostic tests for PSA? -measuring serum PSA, digital rectal exam, transurethral ultrasound35.  PSA? -single chain glycoprotein proteolytic enzyme belonging to the kallikrein family36.  What form is PSA usually found in healthy men? most serum PSA is complexed w ACT or w alpha 2 macroglobulin in healthy men. 37.  characteristic of all commercial PSA assays? use a double antibody sandwhich procedure. 38.  PPV serum PSA above 4.0 ng/mL is about?  the positive predicted value of serum PSA> 4.0ng/mL is 25% early prostate cancer on biopsy39.  What level of PSA would trigger further investigation and why ?at or above 4.0 ng/mL40.  patient w T3 prostate cancer has primary tumor of? primary tumor that extends through the prostate capsule 41.  what does megastatic prostate cancer frequently involve? the bone 42.  most common side effect of treatment for prostate cancer? incompetent ( cant get erection) and incontinent( cant control pee)43.  Which hormone can detect ovulation by immunoassay? LH44.  What disorders will myeloglobin be elevated? acute MI, renal failure, vigourous excercise45.  Recommended Diatary Allowance recommends dietary nutrients required to meet the needs of most healthy pple46.  What patient population can be associated with  increased risk for malnutrition? cancer patients, geriatric, decreased birth weight babies, abdominal surgery patients, and alcoholics47.  which serum proteins are most useful as markers for malnutrion?  prealbumin and albumin 48.  Chronic alcoholism is associated w a high risk for? malnutrition 49.  alpha fetoprotein  marker for hepatacellular and germ cell carcinoma. plasma protein made by fetus50.  what would serum alpha feto protein levels be requested for? DX: spina fibida and hepatacellular carcinoma   

Enzymes

Pancreas

Cardiac Enzymes

Proteins and Tumor Markers