Final Exam Practice Flashcards
1
Q
Patient shows brownish-yellow pigmentation off skin and a sclera, causing you to suspect hepatic jaundice if your diagnosis is correct, you might expect to see Hight levels of what compounds
A
- Conjugated Bilirubin in blood
- Unconjugated bilirubin in blood
- Urobilinogen in the blood
- Urobilinogen in the urine
2
Q
Can unconjugated bilirubin be present in the urine?
A
NO
It is not water soluble and therefore cannot excrete in the urine
3
Q
Is Jaundice caused by conjugated or unconjugated bilirubin
A
Post-Hepatic Jaundice, also called Obstructive Jaundice, is caused by an interruption to the drainage of bile containing Conjugated Bilirubin in the biliary system.
Most common cause are gallstones in the common bile duct and pancreatic cancer in the head of pancreas
4
Q
What is the fate of Urobilinogen
A
In the intestine is directly reduced to brown Stercobilinogen, which can be further oxidized to stercobilin
5
Q
Define Gilbert’s Syndrome
A
Genetic Condition- in which liver doesn’t properly process bilirubin.
Gilbert’s syndrome is due to a mutation of the
UGT1A1 gene with results in decrease activity of the Bilirubin Uridine Diphosphate Glucuronosyltransferase enzyme.
High unconjugated bilirubin due to excess red blood cell breakdown, large bruises,
6
Q
Define Alkaptonuria
A
Rare genetic disorder in which the body cannot process the AA phenylalanine and Tyrosine which occur in Proteins
7
Q
What accumulates due to Alkaptonuria genetic disorder
A
It is accumulation of intermediate substance known as Homogentisic Acid in the blood and tissues.
8
Q
What causes Alkaptonuria
A
Mutation in the HGD gene for the enzyme homogentisate 1,2-deoxygenate
9
Q
Pt presents dark spots in his sclera, black pigmentation on cartilage and collagenous tissue. His urine turns black while standing/exposed to air….you recognize these symptoms to be characteristic of
A
Alkaptonuria Inherited genetic disorder—-recessive condition
10
Q
Why does the urine turn black in Alkaptonuria disorder
A
The deficiency in homogentisic Acid oxidase…it causes homogentisic aciduria: the urine contains elevated levels of homogentisic acid which is oxidized to a dark pigment while exposed to air
11
Q
Define Phenylketonuria
A
(PKU)
Inherited disorder increases levels of Phenylalanine due to mutations in the PAH which results in low levels of enzyme Phenylalanien Hydroxylase (PAH)
Additional: Deficiency in conversion fo L-Phenylalanien to L-Tyrosine cause acculation of phenuylalanine
TX- Dietary restrictions (meat, fish,eggs,
PKU-can lead to intellectual disability, seizures, behavior problems and mental disorders
12
Q
Define Pheochromocytoma
A
A neuroendocrine tumor of the medulla of the Adrenal Gland originating in the Chromaffin cells or extra tissue that failed to involuted after birth that secretes high levels of catecholamines mostly norepinephrine and epinephrine to a lesser extent
13
Q
Define catecholamines
A
Any group of Sympathomimetic amines ( Dopamine, epinephrine norepinephrine) = act as hormones or neurotransmitters
Amine derived form the AA Tyrosine
14
Q
Pheochrmocytoma, a tumor of catecholamines secreting cells causing dangerous hypertension in a patient…these hypertansive episodes, you recommend as a best drug that one which inhibits
A
MAO=Monoamine Oxidase
COMT=Catechol-O-methyltransferase
Both catalyze degradation of catecholamines
15
Q
Define Parkinson’s disease
A
Neurodegenerative movement disorder due to insufficient dopamine production as a result of the idiopathic loss of dopamine-producing cells in the brain.
Administration of L-DOPA (levodopa) is the most common treatment.
Note: Dopamine cannot cross the blood brain barrier .
16
Q
What does MAO stand for and where can it be found
A
Monoamine Oxidase
Enzyme can be found in liver and intestines
This enzyme oxidatively delaminates and inactivated any excess neurotransmitter molecules that may leak out of synaptic vesicles when the neuron is at rest
17
Q
In response to B12 deficiency what conditions may develop in the pt if not treated properly
A
Accumulation of branched Fatty acids incorporated into cell membranes including those of CNS- causing neurologic manifestations
Note: deficiency of B12 can be determined by the levels of methylmalonic acid in blood which is elevated in individuals with decreased absorption of the vitamin
18
Q
Clinical indication of B12 deficiency
A
Pernicious Anemia most common in pt who fail to absorb the vitamin from the intestine
19
Q
Folic Acid supplementation can partially reverse what
A
hematologic abnormalities do B12 deficiency therefor masking cobalamin deficiency
20
Q
B 12 Deficiency causes what 3 type of conditions
A
Pernicious Anemia (life long TX)
Megaloblastic anemia
Hypochromic anemia
Lupus
21
Q
Enzyme abnormalities can lead to Hyperuricemia and Gout include
A
Reduced activity of Hypoxanthine-quinine phosporibosyltransfrease
22
Q
Define Lesch-Nyhan syndrome
A
Formation of uric asic stones in the kidneys (urolithiasis ) and the deposition of Yates crystals in the points (gout arthritis) and soft tissue.
23
Q
What is Lesch-Nyhan characterized by
A
Motor dysfunction
Cognitive defects
Behavioral disturbances = self mutilation
24
Q
What Enzyme deficiency causes Lesh-Nyhan syndrome
A
Hypoxanthine-Guanie phosphoribosyltransferase (HGPRT)
25
Define Dicarboxylic Academia
Elevated methylmalonic Acid In blood are symptoms of Vit B 12 deficiency
Note: Methylmalonic acid = Dicarboxylic acid
26
Hyperuricemia
Elevated uric acid caused by too much of Vit B12
27
Define Hypochromic Anemia
Genetic term for any type of Anemia in which the red blood cells (Erythrocytes) are paler that normal.
(Hyper refers to less & Chromic means Color)
28
Define Hyperchromia
1. Defined as excessive pigmentation (as of the skin)
| 2. A state of the red blood cells marked by increase in the hemoglobin content
29
Define Megaloblastic Anemia
Anemia of Macrocytic classification hat result from inhibition of DNA synthesis during Red blood cell production
Note: DNA synthesis is impaired the cell cycle cannot growers from the G2 growth stage to the Mitosis (M) stage= which leads to continuing cell growth without division which presents as Macrocytosis
30
What tests can be administered to ascertain Vit B12 Def
Gold Standard direct measurement of the Blood Cobalamin
A measurement of Methylmalonic Acid Can provide an indirect method for partially differentiating Vit B 12 and Folate deficiencies
31
# Define Chronic Granulomatosus Disease
Recall as much information as possible :)
Chronic granulomatous disease (CGD) (also known as Bridges–Good syndrome, chronic granulomatous disorder, and Quie syndrome
[1]) is a diverse group of hereditary diseases in which certain cells of the immune system have difficulty forming the reactive oxygen compounds (most importantly the superoxide radical due to defective phagocyte NADPH oxidase) used to kill certain ingested pathogens.
[2] This leads to the formation of granulomata in many organs
32
Chronic Granulomatosus
Simplified
Disease caused by genetic deficiencies in NADPH Oxidase; characterized by sever, persistent infections and the formation of Granulomatosus (nodule ares of inflammation) that sequester the bacteria
33
Define Pompe’s Disease
Glycogen storage disease type II, also called Pompe disease,
1. an autosomal recessive metabolic disorder which damages muscle and nerve cells throughout the body.
2. It is caused by an accumulation of glycogen in the lysosome due to deficiency of the lysosomal acid alpha-glucosidase enzyme.
34
Type 1 Diabetic has blood glucose of 250mg/dL..after insulin injection blood glucose volume decreases to 150 mg/dL
Which of the following changes in liver metabolism would most likely accompany this disease?
Increased Hexokinase Activity
35
Ornithine Transcabamylase deficiency
Orotic Aciduria diagnosis
General Discussion. Ornithine transcarbamylase (OTC) deficiency is a rare X-linked genetic disorder characterized by complete or partial lack of the enzyme ornithine transcarbamylase (OTC).
OTC is one of six enzymes that play a role in the break down and removal of nitrogen the body, a process known as the urea cycle.
36
What is Ornithine use for
L-ornithine is a catalyst in the process that converts ammonia into urea, which can be eliminated through urine.
The liver uses the enzyme arginase and the amino acid L-arginine to synthesize urea and L-ornithine as part of the urea cycle.
37
Which process/reactions will be the lowest in Pt with uncontrolled diabetes mellitus
Pyruvate dehydrogenase reaction
Note: Stimulated Fatty Acid oxidation causes increase in Acetyl-CoA, and this in-turn inhibits Pyruvate dehydrogenase
38
When acetoacetate synthesis is active
Ketone bodies production is stimulated
39
When Pyruvate Carboxylase reaction occurs
Gluconeogenesis is stimulated
40
Microcytic Hypochromic anemia can result from what factors
Dietary deficiency in:
Iron
Pyridoxine
Ascorbate
41
Elevated Homocysteine & Decreases Folic acid levels in pregnant woman are associated with what?
Increased incidence of Neural Tube defects (improper closure=spinal bifida) in the fetus.
Periconceptual supplementation with folate reduces the risk of such defects
42
Homocysteine Methyltransferase
3 different points
1. (BHMT) is a zinc metallo-enzyme that catalyzes the transfer of a methyl group from trimethylglycine and a hydrogen ion from homocysteine to produce dimethylglycine and methionine respectively
2. This enzyme belongs to the family of transferases, specifically those transferring one-carbon group methyltransferases.
3. This enzyme participates in the metabolism of glycine, serine, threonine and also methionine.
43
Wen the insulin/glucagon ratio is high, which of the following enzyme activities is true
Pyruvate Kinase activity increases and PEP carboxykinase decreases
(PEP)= Phosphoenolpyruvate
44
What is Phosphoenollpyruvate Carboxykinase responsible for
(PEPCK) an enzyme in the lease family used in the metabolic pathway of gluconeogenesis.
It converts oxaloacetate into phoshoenolpyruvate and CO2
45
Insulin increases/decrease what
Increases glycolysis
Decreases gluconeogenesis
46
Deficiency of which enzyme is likely to account for Hemolytic anemia
Pyruvate Kinase
Note: Hemoglobin Oxygen dissociation curve shifts to R (reduced affinity of hemoglobin for oxygen) this is a characteristic for increased 2.3-BPG concentration.
Red blood cells with Pyruvate kinase deficiency produce more of 2,3-BPG as compensatory effect
47
Analysis of pt serum revealed an elevated VLDl. Which of the following mechanism account for the finding
Decreased activity of Lipoprotein lipase
48
VLDL
IDL
LDL.....what do they stand for
VLDL=very low density lipoprotein
Produced more with increased activity of ACAT
IDL=Intermediate density lipoprotein
LDL= Low density Lipoprotein
49
What happens to cholesterol as its synthesized in the liver
It is either converted to bile salts or esterified by ACAT (Acyl CoA: Cholesterol acyltransferase), packed into VLDLs and transported to tissues
Cholesterol in VLDLs is either esterified to LCAT(lecithin-Cholesterol acyltransferase) or exchanged for triacylglycerols form HDLs
50
Triacylglycerols in VLDLs ...what happens
Are degraded by lipoprotein lipases.
51
# Define Mycophenolic acid
It is used to prevent graf rejections by depriving lymphocytes of nucleotides via
Drug used to prevent graf rejection
Drug is reversible inhibitor of IMP
Drug is immunosuppressant
Inhibition of IMP dehydrogenase
(IMP)=Inosine monophosphate dehydrogenase
52
14 year old girl has history of Diarrhea and fatty stools. Her serum cholesterol & triacylglycerol levels are extremely low. You recognize her symptoms resulting from which condition
Abetalipoproteinemia
53
Abetalipoproteinemia define
Impaired Chylomicrons assembly- dietary triacylglycerols and cholesterol cannot enter bloodstream
is a disorder that interferes with the normal absorption of fat and fat-soluble vitamins from food.
It is caused by a mutation in microsomal triglyceride transfer protein resulting in deficiencies in the apolipoproteins B-48 and B-100, which are used in the synthesis and exportation of chylomicrons and VLDL respectively
54
Hyperliproproeinemia type III
Impaired cholesterol and triglycerides metabolism leading to hyperlipidemia
55
Lipoprotein lipase deficiency
Impaired fatty acid metabolism leading to hypertriglyceridemia
56
LCAT deficiency
Accumulation of unesterified cholesterol
57
28 old, blood smear reveals large RBC & hypersemented neutrophils. Further analysis reveals a mild homocystinemia. Which of the following enzymes is most likely have abnormal low activity
Cystathionine synthase
58
What is Cystathionine synthase responsible for
Conversion of homocysteine to cysteine
59
A man with history of genetic disease undergoes hip replacement surgery for arthritis. During operation the surgeon notes dark pigmentation in the mans cartilage. His ochronotic arthritis is most likely caused by oxidation and plymerization of excess tissue
Homogentisic acid
Condition is Alkaptonuria
60
Physical examination of a 21 year old mentally retarded man revealed hepatomagaly and spenomagaly. Bone marrow biopsy showed macrophages with “crumpled tissue paper” appearance of the cytoplasm. These symptoms are diagnostic of?
Gaucher’s Disease
61
Define Gauchers Disease
(GD)is a genetic disorder in which glucocerebroside (a sphingolipid, also known as glucosylceramide) accumulates in cells and certain organs.
It is caused by a hereditary deficiency of the enzyme glucocerebrosidase (also known as glucosylceramidase), which acts on glucocerebroside. When the enzyme is defective, glucocerebroside accumulates, particularly in white blood cells and especially in macrophages (mononuclear leukocytes).
Gaucher's disease is the most common of the lysosomal storage diseases.[2] It is a form of sphingolipidosis (a subgroup of lysosomal storage diseases), as it involves dysfunctional metabolism of sphingolipids.[3]
62
Gaucher’s disease is characterized by
The disorder is characterized by bruising, fatigue, anemia, low blood platelet count and enlargement of the liver and spleen
63
In Guchers disease what accumulates and what is affected by this accumulation
Glucocerebroside can collect in the spleen, liver, kidneys, lungs, brain, and bone marrow.
Manifestations may include enlarged spleen and liver, liver malfunction, skeletal disorders or bone lesions that may be painful, severe neurological complications, swelling of lymph nodes and (occasionally) adjacent joints, distended abdomen, a brownish tint to the skin, anemia, low blood platelet count, and yellow fatty deposits on the white of the eye (sclera).
64
Define hepatomegaly
Hepatomegaly is the condition of having an enlarged liver.
It is a non-specific medical sign having many causes, which can broadly be broken down into infection, hepatic tumours, or metabolic disorder.
Often, hepatomegaly will present as an abdominal mass. Depending on the cause, it may sometimes present along with jaundice.[1]
65
Splenomegaly define
Abnormal enlargement of the spleen
66
During bile salt metabolism in the intestine
Cholic acid is converted to deoxycholic acid
Intestinal bacteria converts primary bile salts to secondary bile salts.
67
If you suspect a deficiency of folate in the body of your patient, you know it can be a diagnosed by high urinary excretion of ?
Formiminoglutamate
Folic acid is involved in histidine catabolism (conversion of histidine to glutamine, with formiminoglutamate as intermediate)
68
Histidine can be converted to what ?
Glutamate
With formiminoglutamate as intermediate
69
Acute intermittent porphyria is characterized by what
Deficiency of uroporhyrinogen 1 synthase
Accumulation of ALA & porphobilinogen in the patien blood and urine
Toxic effects on the nervous system that cause neuropsychiatric symptoms
Increased synthesis of ALA synthase
70
Acute intermittent porphyria is characterized by all excerpt
Cutaneous Photosensitivity
71
In order to increase the reverse transport of cholesterol form peripheral tissue to the liver, you can recommend the drug that ?
Stimulates the synthesis of the SR-B1 receptor
Stimulates the expression of the ABCA1 or ABCG1 protein
72
In Salvage reaction for purines
Purine nucleotides are formed from purines and phosporibosyl phosporylation
(Should be phosporibosyl pyrophosphate)
73
In salvage reactions for purines: purine nucleotides are? give example and are synthesized form what ?
Purine nucleotides (AMP,GMP, IMP) are synthesized from purines from degradation pathway of nucleotides from cellular nuclei acid or food
74
What does the salvage reaction of purines involve?
The reactions involves activated ribose-5-phosphate:
| 5-phosphoribosyl-1-puyrophosphate
75
Nucleoside =
Sugar + Base
76
Nucleotide=
Sugar + Base + Phosphate
77
The carbons of all amino acids end up in the TCA cycle. Which group of AA has common entry point to the cycle
A. Arginine, proline, glutamine
C. Arginine, glutamate, histidine
There were two answers..
Note: Glutamine & Glutamate are inter-convertible, the entry point for Arg, Pro, His, Gln, & Glu is Alpha-ketoglutarate via glutamate
78
A combination of elevated conjugated bilirubin, normal unconjugated bilirubin in the blood and absence of sterocobilin formation in a jaundiced patient suggests what?
Bile duct obstruction
79
Gilbert’s syndrome & Criggler-Najjar syndrome are associated with deficiency in what enzyme and show elevation in what type of bilirubin
Election in unconjugated bilirubin in the blood
Both associated with bilirubin-UDP glucuronyltransferase deficiency
80
What occurs with Bile duct obstruction
Conjugated bilirubin cannot enter the intestine.
Stercobilin is produced in the intestines from urobilinogen (which in turn is from conjugated bilirubin entering via bile duct)
Without sterocobilin the stools are pale in color (Clay color)
81
2 year old is seen by her doctor and is noted to have mental retardation with enlarged liver and spleen. Bone marrow revealed the presence of numerous foam cells. This patient has
Neiman-Pick disease
82
Neimann-Pick disease
Niemann-Pick disease (NPD) is a group of diseases passed down through families (inherited) in which fatty substances called lipids collect in the cells of the spleen, liver, and brain
83
Neiman-pick disease is considered one with inability to what
One of sphinglipidosis (inability of sphingomyelin degradation) liver deposition in liver and spleen (enlargment).
The deposits in cells look “foamy” neurodegeneration
84
Analysis of blood plasma of your infant patient shows turbidity with elevated TG level. A plasma sample has been left in refrigerator over night revealed cream-colored material floating on top. The underlying plasma was clear. Which type or hyperliporoteinemia is most likely present in this patien?
Type 1
85
In Type 1 Hyperlipoproteinemia is defined by what deficiency
Lipoptotein lipase deficiency: triglycerides (TG) from chylomicrons and cannot be degraded.
After separation of fat, plasma is clear because only chylomicrons are increased (other lipoproteins are in norm)
86
In glucose tolerance test, an individual is given to drink large amount of glucose. If the individual is normal, ‘tis ingestion should result in what?
An enhanced activity of Acetyl-CoA Carboxylase
87
Indicate which components contribute to the purine ring
Tetrahydrofolate contributes atom 7 of purine
```
Glutamine: Atom 1 & 4
Glycine: Atom 2
CO2: Atom 5
Aspartate: Atom 6
Formyltetrahydropholate:
Atom 3 & 7 (purine)=cyclohexane
```
88
Which combination of amino acids if removed from the diet of an adult would result in negative nitrogen balance
Phenylalanine, alanine, serine
Negative nitrogen balance: lack of essential amino acids in diet.
89
Name all essential AA
| Define essential acid
Essential means, body cannot produce therefore need to be provided in the dietary intake
Essential AA:
```
1- histidine
2-leucine
3-isoleucine
4-lysine
5-methionine
6-phenylalanine
7-tryptophan
8-threonine
9-Valine
```
90
Acetyl-CoA Carboxylase is responsible for what
Acetyl CoA carboxylase plays an essential role in regulating fatty acid synthesis and degradation
The carboxylase is controlled by three global signals—glucagon, epinephrine, and insulin—that correspond to the overall energy status of the organism. Insulin stimulates fatty acid synthesis by activating the carboxylase, whereas glucagon and epinephrine have the reverse effect.
91
You found elevated levels of phenylalanie and phenylpyruvate in the blood of a new born infant. Which of the following enzymes you suppose to be deficient in this baby
Dihydrobiopterin reductase
92
What happens in Phenylketonuria
Blocked transformation of phenylalanine to tyrosine.
The deficiency of phenylalanine Hydroxylase which is dependent on dihydrobiopterin reductase
Phenylalanine and phenylpyruvate accumulate in the blood and tissues
93
If your patient reveals methylmalonic Acidemia, you know immediately that a defect is his/her metabolism is cause by
Deficiency in B12 (cobalamin)
94
Heinz bodies are histological hallmark of what disorder
Glucose-6-Phospate dehydrogenase deficiency
95
What are he is bodies
Precipitated dentaurated hemoglobin in RBC
96
G6PD stands for what and deficiency of it leads to what
Glucose 6-phosphate dehydrogenase
G6PD deficiency leads to increased oxidation (less NADH and reduced glutathione) which causes hemoglobin denaturation
97
Which of the following enzymes is believed to be most responsible foe the development of cataracts in individual with diabetes mellitus
Aldo’s reductase
98
Failure of normal DNA synthesis in the lymphocytes of a patient with SCID is a result of inhibition of which of the following enzymes fo purine nucleotide metabolism
Ribonucleotide reductase
99
What does SCID stand for and define it
Sever Combined immunodeficiency
Deficit of adenosine deaminase causing accumulation of deoxyadensine.
Deoxyadenosine inhibits ribonucleotide reductase.
Ribonucleotide reductase is crucial for DNA synthesis: it converts ribonucleotide to deoxyribonucleotides (for DNA synthesis the deoxy-form is requred)
When deoxyadenosine accumulates, the other deoxyribonucleotides cannot be produced and DNA synthesis stops
100
Which of the following lis characteristic of low insulin level
Decreased activity of lipoprotein lipase
Note: insulin stimulates lipoprotein lipase in adypocytes
When insulin is low (in fasting) lipoprotein lipase activity in adipose tissue is low to prevent adipose tissue from taking up and storing circulating triacylglycerols
101
Write on paper:
If insulin is low ....................is low and gluconeogenesis is .....................
If insulin’s is low .................is low and .................3-.......................(............)
If insulin is low .............is low, decreased ............... .............( in ....................)
Insulin stimulates synthesis of what ?
Glucose is low
Increased gluconeogenesis
Glucose is low
Increased 3-hydeoxybutyrate (ketone body)
```
Glucose is low
Pyruvate dehydrogenase (in Glycolysis)
```
Synthesis of cholesterol
102
Diagnosis of Adrenal Pheochromocytoma or choleserohrmacytomas is based on the urinary excretion of
Vanillylmandelic acid derived from epinephrine and norepinephrine (VMA)
103
Homovanillic acid derives from what
Dopamine
104
A person whose sole protein source is corn may be deficient in which AA
Tryptophan & lysine
Note: also leading to nicotinamide (niacin) deficiency (pellagra)
105
Cholestyramine exerts its hypocholesterolemic effect by interacting with
Bile Acids
106
What is Cholestyramine
Bile acid sequestration
It binds bile salts in the intestines to prevent them to reabsorb and promote their excretion.
Removal of bile salts relieves the inhibition on bile acid synthesis in the liver
107
Markedly reduced levels of cholesterol esters in blood lipoproteins results from a deficiency of
Lecithin: Cholesterol acyltransferase (LCAT)
Note: deficiency will case accumulation of non-esterified cholesterol in blood (high plasma unesterified cholesterol and low plasma cholesterol ester)
108
The circulating form of hemoglobin that is used to assess blood glucose concentration in diabetes mellitus is
Hemoglobin A1
Hemoglobin A1 is nonenzymaticaly glycosylated (glycated) and extent of glycosylation depends on glucose plasma concentration
109
Which of the following genetic disorders is due to a defect in lysosomal metabolism
Hurlers disease
110
Ehlers-Danlose syndrome is
Genetic connective tissue disorder
111
Von Gierke imperfecta is
Glycogen storage disease
| Glucose 6-Phosphatase deficiency
112
Osteogenesis Imperfecta
Bone fragility, collagen gene mutation
113
Andersen’s disease
Glycogen storage disease
114
OXPHOS disease
Oxidative phosphorylation disease
| This disease impacts tissues with the highest energy demand (brain, nerves, retina, skeletal and cardiac muscle)
115
Which of the following enzymes is regulated by reversible covalent modification
Pyruvate dehydrogenase
```
Note:
Phosporylated PDH (inactive)
Dephosphorylated PDH (active)
```
116
Person with insulin dependent diabetes mellitus failed to take insulin regularly and was found to have high VLDL and as a consequence, which of the following compounds in the blood would be elevated
Triacylglycerols
117
All of the following increase the extent of sickling in sickle cell anemia patients by increasing the proportion of deoxygenated hemoglobin S except
Increased carbon monoxide
| Increased ph
118
What enzyme is responsible to leukotriene production
Arachidonate 5-lipoxigenese
119
Define leukitriene
Family of eicosanoid inflammatory mediators produced in leukocytes by the oxidation of arachnoid acid (AA) and the essential fatty acid eicosapentaenoic acid (EPA) by the enzyme arachidonate 5-lipoxygenase
120
Leukotriene are responsible for
any of a group of compounds derived from unsaturated fatty acids, primarily arachidonic acid, that are extremely potent mediators of immediate hypersensitivity reactions and inflammation, producing smooth muscle contraction, especially bronchoconstriction, increased vascular permeability, and migration of leukocytes to areas of inflammation.
121
Disease characterized by increased leukotriense synthesis is
Asthma
122
Can asthma be treated with Aspirin
NO!
Because it is part of (NSAIDs)
Notsteroidal anti-inflammatory drugs
123
What are NSAIDS
Nonsteroidal anti-inflammatory drugs
-drug class that reduce pain, decrease fever, prevent blood clots and, in higher doses, decrease inflammation
It’s action=enzyme inhibitor
124
What are some examples of NSAID
Aspirin
Ibuprofen (Motrin, Advil)
Naproxen (Aleve, Anaprox DS, Naprosyn)
Indomethacin (Indocin)
Phenylbutazone
Celebrex
125
Disease characterized by increase of leukotriene synthesis is ..........and it should be treated with ?
Asthma
Treated with Inhibitors of 5-Lipoxygenase and antagonists of leukotriene receptors
Pg 214
126
What enzyme is deficient in hereditary fructose intolerance
Aldolase B
Pg 138
127
In the hereditary fructose intolerance.. what metabolites accumulate and what are the symptoms of the disease?
Fructose 1-Phosphate accumulates
ATP falls and AMP rises= Hyperuricemia, lactic acidosis, hypoglycemia, impaired protein synthesis (example..decrease in blood clotting factors) impaired glycogenolysis.
Diagnosis: Fructose in urine
P 138
128
Respiratory distress syndrome is seen most frequently in ..................and is caused by
Premature Infants
Cause by insufficient production of pulmonary/lung surfactants
P 204
129
Malignant carcinoid tumor is associated with increase synthesis of ?
Vasoactive hormones (primarily Serotonin)
130
What are the two primary functions of thiamine.
Formation or degradation of
Alpha -ketone by (transketolase) and in the oxidative decarboxylation of Alpha-ketone Acid (Pyruvate dehydrogenase complex, alpha-ketoglutarate dehydrogenase complex)
P379
131
What is Nitrogen balance
It is when the amount of nitrogen consumed equals that of the nitrogen excreted in the urine (primarily as urinary urea nitrogen UUN)
P367
132
Where are HDLs formed and what is their function
HDL particles are formed in blood by addition of lipid to apo A-1 and apolipoprotein made within the liver and intestine is secreted into blood.
Function to keep lipids (primarily triacylglycerols (TAG) and Cholesteryl esters) soluble as they transport them between tissues.
Responsible for Uptake fo unesterified Cholesterol & esterification of cholesterol and reverse cholesterol transport
P 234-236
133
Faulty collagen synthesis is resulting form inherited defects caused by several disease. List some of them that you learned.
Ehlers-Danlos syndrome
Osteogenesis imperfecta
P48-49
134
Name 5 amino acids that are essential for humans
```
Leucine
Isoleucine
Tryptophan
Threonine
Methionine
Valine
Histidine
Phenylalanie
```
P262
135
The predominant nitrogen metabolite excreted in urine in humans.
Urea
P253
136
What proteins serve as the primer of glycogen synthesis
Fragment of existing glycogen or glycogenin (if glycogen is absent)
Pt 126-127
Note: fragment of glycogen can serve as a primer in cells whose glycogen stores are not totally depleated..in absence of glycogen, protein glycogenin can serve as a acceptor of glucose residues form UDP-glucose
137
Name 3 major apolipoproteins and list their functions
Apo A-1: major apolipoprotein
Of HDL-activates LCAT
Apo-100: apolipoprotein of VLDL, IDL, LDL
Apo-100 is recognized by receptors of endocytosis
Apo C-II: Activates lipoprotein lipase in capillaries (transferred form circulating HDLs to other lipoproteins)
Apo E: liver cells have receptor Apo E- lipoproteins can be endocytosed degraded in lysosomes (Apo E transferred from circulating HDL to other lipoproteins: chylomicron remnants, IDLs)
138
In fasting what molecule allosterically stimulates glycogen breakdown in muscle?
AMP (Adenonine Monophosphate) - (allosteric activator of glycogen phosphorylase)
P134
139
Name glycogen storage diseases type 1
von Gierke disease
140
What is the enzyme deficiency in Glycogen storage disease 1 (von Gierke disease)
Enzyme deficiency is Glucose 6-Phosphate
141
What are the symptoms of Von Gierke disease
```
Severe fasting hypoglycemia
Fatty liver
Hepato & amp; renomegaly
Progressive renal disease
Growth retardation
Delayed puberty
Lactic Acidemia
Hyperlipidemia
Hyperuricemia
```
P130
142
What sets follow glutamate formation during amino acid catabolism
Oxidative glutamate deamination in which the A group is liberated as free ammonia (catalyzed by glutamate dehydrogenase)
P252
143
Pellagra is a disease which results form a deficiency of
Niacin ( Vit B3)
144
What clinical features are associated with Pellagra
Three D’s:
Dermitis
Diarrhea
Dementia
P380
145
Statins are drugs used in treatment
Treatment of hypercholesterolemia
146
What is the mechanism of action of Statins
| tx: hypercholesterolemia
They inhibit cholesterol synthesis
(Reversible competitive inhibitors of HMG CoA reductase)
(Hydroxy 3-Methyl-glutaryl)
P224
147
Cellular cAMP levels can be increased by inhibiting what enzyme?
cAMP phosphodiesterase
(Cyclic Adenosine monophosphate)
P95-96
148
What enzyme liberates arachidonic acid from the plasma membrane?
Phospholipase A2
P207
149
What is Glycogen storage disease type V
McArdle Syndrome
150
What is the main organ and enzyme affected in this Glycogen storage disease type V
(McArdle syndrome)
Skeletal muscle,
The enzyme affected is glycogen phosphorylase (or myophosphorylase)
P 129
151
By what mechanism does oligomyocin poison oxidative phosphorylation?
Oligomycin - antibiotic which inhibits the ATP synthase by closing its proton channel, which is necessary for oxidative phosphorylation of ADP to ATP and preventing proton re-entry into mitochondrial matrix...
Note: the inhibition of ATP synthesis would also stop electron Transport chain
P78
152
Allopurinal is used to inhibit what enzyme
Xanthine oxidase
Allopurinal (drug used to decrease High blood uric acid levels)
Used to prevent Gout, kidney stones)
153
Allopurinal is used to inhibit the enzyme Xanthine oxidase.... what is the action of this enzyme
Xanthine oxidase catalysts the oxidation of Hypoxanthine to Xanthine and oxidation of Xanthine to uric acid (part of degradation of purine nucleotides)
154
Classical galactosemia is caused by inherited deficiency of what enzyme
Galactose-1-phosphate uridylyltransferase
155
What toxic metabolites are responsible for the clinical manifestations of Classical galactosemia
Galactitol
Galactose-1-phosphate
P141
156
Pyruvate dehydrogenase is inhibited by
NADH & AMP; acetyl CoA
157
What does pyruvate dehydrogenase require
Thiamine pyrophosphate (TPP)
Thiamine (Vit B1)
158
Pyruvate Carboxylase is activated by
Acetyl CoA
159
What does Pyruvate Carboxylase require
Biotin (Vit B7)
160
What does Alanine aminotransferase require
pyridoxal phosphate (active form of Vit B6)
| If your liver is damaged it will release more ALT=alanine aminotransferase into your body
Elevated liver enzymes
161
What is phosphorylated and inactivated by protein kinase
Pyruvate kinase
162
What forms products when NADH levels are elevated
Lactate dehydrogenase (LDH)
LDH=catalyze the conversion of lactate to pyruvic acid and back, as it converts NAD+ to NADH and back
