Midterm 2 Open Answers Flashcards Preview

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Flashcards in Midterm 2 Open Answers Deck (32)
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1
Q

What kind of covalent bond is formed between thrombin and antithrombin?

A

ester bond between active Ser and the carboxylic group of the cleaved peptide bond in antithrombin

2
Q

Which is the cofactor in the thrombin catalyzed activation of F XIII ?

A

fibrin

3
Q

Write down the substrates and products of the reaction catalyzed by FXIIIa (Name the amino acids in the substrates and the name of the formed bond)

A

S: lysine and glutamine side chains in gamma and alpha chains of fibrinP: gamma-glutamyl-lysine isopeptide and ammonia

4
Q

What kind of covalent bond is formed between thrombin and α2-macroglobulin?

A

isopeptide bond between an ε–amino group of Lys in thrombin and a carboxylic group from a Gln-Cys thioester bond in α2-macroglobulin

5
Q

Which proteases are necessary for the destruction of the intrinsic tenase and the prothrombinase complexes ?

A

thrombin, activated protein C

6
Q

Which protein cofactors are necessary for the destruction of the intrinsic tenase and the prothrombinase complexes?

A

thrombomodulin, protein S

7
Q

What is the mode of action of streptokinase ?

A

forms a complex with human plasminogen, in which plasminogen gains activity as plasminogen activator

8
Q

List two distinct functions of von Willebrand factor

A

carrier of F VIII, mediator of platelet adhesion at high shear

9
Q

What is the mode of antithrombolytic action of TAFI (Thrombin activatable fibrinolysis inhibitor)?

A

cleaves C-terminal Lys residues and decreases the binding sites for tPA and plasminogen in fibrin and moderates the cofactor of fibrin in plasminogen activation

10
Q

What kinds of conjugation occur in 2nd phase of biotransformation ?

A

glucuronidation, sulfation, glutatione conjugation, acetylation, amino acid conjugation, methylation

11
Q

Which enzymes catalyze glucuronidation ?

A

UDP-glucuronosyl-transferases

12
Q

Name diseases caused by gene expression disorders of UDP-glucuronosyl-transferases!What kind of hyperbilirubinemia is caused by them ?

A

Gilbert disease, Criegner-Najjar syndromeunconjugted bilirubin

13
Q

What is the dominant type of conjugation in case of electrophilic intermediates?

A

glutathione conjugation

14
Q

What are the steps of glutathione conjugation?

A

conjugation with glutatione, loss of glutamate and glycine, conjugation with acetyl group

15
Q

Which pathways of the intermediary metabolism involve biotransformation reactions?

A

cholesterol synthesis, steroid biosynthesis, bile acid synthesis, bile acid conjugation, eicosanoid synthesis-conjugation, leukotriene formation, bilirubin conjugation, catecholamine synthesis

16
Q

What is the role of the primary cilium of endothelial cells?

A

Detect flow rate and cause intracellular change in calcium concentration

17
Q

Which compound forms a secondary matrix in thrombi in addition to thrombin?

A

NETs: Neutrophil Extracellular Traps

18
Q

Write down the targets of TFPI in the order of their binding

A

Forms complex with Xa and inhibits it, then goes on to bind and inhibit VIIa

19
Q

Which phase of biotransformation is mediated by transporters?

A

Phase III

20
Q

What is the dominant chemical reaction in the 1st phase of biotransformation?

A

Hydroxylation

21
Q

What enzymes catalyze the majority of the reactions in the 1st phase of biotransformation?

A

Cytochrome P450 monooxygenase complex family

22
Q

What kind of solubility change is caused by biotransformation reactions?

A

Substance is made more water-soluble so that it can be excreted

23
Q

What is the first enzyme component of the microsomal respiratory chain and what is the electron donor?

A

Enzyme: Cytochrome P450 ReductaseDonor: NADPH

24
Q

List 3 major targets of thrombin in the positive-feedback loops in blood plasma

A

Factors V, VIII, and XI

25
Q

List at least 3 different in vivo triggers of the intrinsic pathway of blood coagulation (through activation of factor XII)

A

NET, polyphosphates, RNA

26
Q

What are the sources of polyphosphates in vivo?

A

Platelets

27
Q

Name some organs which express P450 isoenzymes involved in drug metabolism

A

Liver, skin, intestines, lungs

28
Q

What is the electron donor for monooxygenases in drug metabolism?

A

NADPH

29
Q

What kind of ROS can be formed during P450 monooxygenation?

A

Superoxide Anion

30
Q

What are the phases of biotransformation?

A

Phase I: PreparationPhase II: ConjugationPhase III: Excretion

31
Q

Which phases of biotransformation are mediated by enzymes?

A

Phase I (CYP450 monooxygenases)Phase II (UGT, ST, GST, AT, MT, Acetyltransferases)

32
Q

What is the cofactor for glucuronidation?

A

UDP-Glucuronate