NPNs & PROTEINS Flashcards
(135 cards)
1
Q
Present in highest concentration in the blood ; formed in the liver from CO2 and ammonia ; major excretory product of the metabolism of proteins and other nitrogen-containing chemicals
A
Urea
2
Q
Concentration of urea is expressed in terms of nitrogen content (BUN) :
A
BUN X 2.14 = urea
Urea / 2.14 = BUN
3
Q
Reference method for NPN measurement
A
Isotope dilution mass spectrometry
4
Q
Chemical method for urea is also called
A
Fearon method / diacetyl monoxide method / direct method
5
Q
Chemical method (Fearon) : color of diazine
A
Yellow
6
Q
Enzymatic method for urea
A
Urease method / Indirect method
7
Q
Colorimetric enzymatic method for urease : Nessler’s reagent
A
Dipotassium mercuric iodide / K2(HgI4)
8
Q
Colorimetric enzymatic method for urease : color of dimercuric ammonium iodide
A
Yellow-orange
9
Q
Colorimetric enzymatic method for urease : components of Berthelot reagent
A
Sodium hypochlorite + phenol + sodium nitroprusside
10
Q
In GLDH-coupled reaction, NAD (product) is detected and measured with ____
A
Decreased absorbance @ 340 nm (UV)
11
Q
Measurement of the increase in conductivity due to NH4+ (ammonium ions) and CO32- (carbonate ions)
A
Conductimetric
12
Q
BUN Reference value
A
6-20 mg/dL
13
Q
Reference value for BUN/Creatinine ratio
A
10 - 20 : 1
14
Q
Increased BUN is termed as
A
Azotemia
15
Q
Azotemia due to dehydration, low blood volume, high protein diet, increased protein catabolism
A
Pre-renal azotemia
16
Q
Value of BUN:creatinine ratio and creatinine in pre-renal azotemia
A
BUN/crea ratio >20 ; Normal creatinine
17
Q
Azotemia due to low excretion (glomerulonephritis, renal failure)
A
Renal azotemia
18
Q
Azotemia due to urinary tract obstruction (nephrolithiasis, tumors, severe infection)
A
Post renal azotemia
19
Q
Value of BUN:creatinine ratio and creatinine in renal and postrenal azotemia
A
BUN/Crea ratio >20 ; High Creatinine
20
Q
Postrenal azotemia : very high plasma urea concentration accompanied by renal failure
A
Uremia/uremic syndrome
21
Q
Value of BUN:creatinine ratio and creatinine in uremia/uremic syndrome
A
High BUN, High Crea, Low GFR
22
Q
Repeated dialysis, liver disease, low protein diet
A
Low BUN
23
Q
NPNs from most to least concentrated
A
Urea
Amino acid
Uric acid
Creatinine
Creatine
Ammonia
24
Q
NPN : 45-50%
A
Urea
25
NPN : 25%
Amino acid
26
NPN : 10%
Uric acid
27
NPN : 25%
Creatinine
28
NPN : 1-2%
Creatine
29
NPN : 0.2%
Ammonia
30
Creatinine is a substance formed from
Methionine, arginine, glycine
31
Excreted into plasma at a constant rate proportional to an individual’s MUSCLE MASS
Creatinine
32
Creatinine is removed from circulation by ______ ; concentration is _____ related to GFR
glomerular filtration ; Inversely
33
Creatinine analytical method : colorimetric, ENDPOINT, nonspecific ; subject to positive bias due to ascorbic acid, glucose, glutathione, keto acids, uric acid, cephalosporins
Chemical method (Jaffe)
34
Creatinine + alkaline pi rate —> red-orange tautomer
Jaffe reaction
35
Techniques to improve Jaffe reaction
Kinetic - timed rate reaction
Use of adsorbents : Lloyd’s reagent (sodium aluminum silicate), Fuller’s Earth (Magnesium aluminum silicate)
36
Adsorbent : LLOYD’S REAGENT
Sodium aluminum silicate
37
Adsorbent : Fuller Earth’s reagent
Magnesium Aluminum silicate
38
POD-coupled : oxidized chromogen aka
Quinoneimine
39
POD-coupled : color of quinoneimine
Red to red-purple
40
Standard formula for creatinine clearance
C = Urine crea (mg/dL) x volume of 24h urine (mL/min / plasma or serum crea (mg/dL)
41
Creatinine clearance formula if the patients is a child, physically wasted, or obese
C = U x V / P (1.73 / Actual body surface area)
42
Variables used in Cockcroft-Gault formula
Age
body weight
serum creatinine
gender
43
Cockcroft-Gault correction factor (if patient is a female)
X 0.85
44
MDRD formula variables (OLD)
Creatinine, BUN, Albumin
Age
Race
Gender
45
MDRD formula variables (NEW)
Creatinine
Age
Race
Gender
46
Decreased creatinine clearance or GFR may be due to _____
Impaired renal function
47
CKD stage : kidney damage with normal or high GFR ; GFR value
Stage 1 ; 90 and above
48
CKD stage : kidney damage with normal or low GFR ; GFR value
Stage 2 ; 60-89
49
CKD stage : moderate low GFR ; GFR value
Stage 3 ; 30-59
50
CKD stage : severely low GFR ; GFR value
Stage 4 ; 15-29
51
CKD stage : kidney failure ; GFR value
Stage 5 ; 15 or less
52
Product of catabolism of purines in nucleic acids or nucleoproteins ; relatively insoluble in plasma ; can be deposited in the joints and tissues at concentrations >6.8 mg/dL
Uric acid
53
Chemical method for uric acid determination
Phosphotungstic method / Caraway method
54
Catalysts used in Caraway method
Sodium carbonate
55
Uric acid reference value (MALE)
3.5 - 7.2 mg/dL
56
Uric acid reference value (FEMALE)
2.6-6.0 mg/dL
57
Chronic nephritis, alcoholism, gout, leukemia, chemotherapy, Lesch-Nyhan syndrome
Hyperuricemia
58
Fanconi syndrome,severe liver disease, purine inhibitors, allopurinol
Hypouricemia
59
Produced from the catabolism of amino acids ; toxic compound metabolized exclusively in the liver via the urea cycle
Ammonia
60
Measurement of pH change as Ammonia diffuses through a selective membrane
Potentiometric
61
Ammonia reference range
19-60 ug/dL
62
Building block of proteins
Amino acid
63
Determined by the acidic and basic amino acid monomers
Net charge and electrophoretic mobility
64
The pH at which a particular protein has a net charge equal to zero
Isoelectric point
65
Protein Solubility
Lowest at isoelectric point, hydrophilic and more soluble when charged
66
Protein nitrogen content
16%
67
Protein structure level : number and types of amino acids in a SPECIFIC amino acid sequence
Primary
68
Protein structure level : Regularly REPEATING structures stabilized by hydrogen bonds between amino acids
Secondary
69
Protein structure level : OVERALL shape or conformation of the protein molecule
Tertiary
70
Protein structure level : Results from the interaction of MORE THAN ONE A protein molecule or subunit
Quaternary
71
Serum samples are applied close to the cathode end of a support medium that is saturated with an alkaline buffer (pH ___) at which proteins carry a ___ charge and migrate toward the ____
8.6 ; negative ; anode
72
Stains used in protein electrophoresis
Coomasssie brillian blue
Ponceau S
Amido black B
Lissamine green
73
Specialized colorimeter designed to can and quantitate electrophoretic pattern
Densitometer
74
Uses a higher voltage coupled with a cooling system and a more concentrated buffer ; separates proteins into 12 or more bands ; detects unusual monoclonal bands
High-resolution protein electphoresis
75
Indicator of malnutrition ; forms a distinct band in CSF electrophoresis
Prealbumin
76
Prealbumin transports T4 as _____
Thyroxine-binding prealbumin
77
Prealbumin forms a complex with ______
Retinol binding protein / vitamin A
78
Major contributor to plasma osmotic or oncotic pressure ; general transport protein
Albumin
79
Most abundant serum protein
Albumin
80
Increased level in amniotic fluid ; increased in adult serum in cases of hepatocellular carcinoma
Alpha-fetoprotein
81
Protease inhibitor ; major component of the alpha 1 region
Alpha - antitrypsin
82
Deficiency is associated with SERPINA 1 gene mutation and causes juvenile hepatic cirrhosis, pulmonary emphysema
Alpha 1 - antitrypsin
83
Binds progesterone and some drugs ; negatively charged even in acid pH ; has a very high carbohydrate content
Alpha 1 - acid glycoprotein
84
Protease inhibitor ; binds prostate-specific antigen
A1-antichymotrypsin
85
Transports vitamin D ; low level may lead to abnormal calcium levels
Gc-globulin
86
Protease inhibitor ; largest non-Ig protein ; 10x increase in nephrotic syndrome, protein-losing enteropathy
A2-macroglobulin
87
Binds hemoglobin to preserve iron ; low level seen in hemolytic disorder, intravascular hemolysis
Haptoglobin
88
Copper-binding protein ; has oxidase activity ; low serum level in Wilson’s disease
Ceruloplasmin
89
Transports iron ; low level seen in IDA (pseudoparaprotein)
Transferrin
90
Immune response ; most abundant complement protein
C3 complement
91
Binds heme ; low level in intravascular hemolysis
Hemopexin
92
Component of MHC or HLA molecules ; used to measure GFR
B2-microglobulin
93
Enhances phagocytosis in inflammatory disease ; most sensitive ; 1000x increase in inflammatory states
CRP
94
Used as a marker for cardiovascular risk
hsCRP
95
Antibodies produced by plasma cells
Imunnoglobulins
96
Incraeased protein loss ; malnutrition/malabsorption ; decreased synthesis ; increased protein catabolism
Hypoproteinemia
97
Monoclonal gammopathy ; dehydration
Hyperproteinemia
98
Low albumin ; 10x increased of a2-macroglobulin
Nephrotic syndrome
99
Polyclonal gammopathy
Hepatic cirrhosis
100
Beta-gamma bridging ; increased IgA in beta and gamma region
Liver cirrhosis
101
Monoclonal spike/gammopathy ; 1 immunoglobulin type is increased
Multiple myeloma
102
Alpha1 globulin flat curve
Alpha 1 - antitrypsin deficiency
103
a1- and a2- globulin spike
Acute inflammation
104
Increased a1-globulin, a2-globulin, and gamma globulin
Chronic inflammation
105
Flat gamma curve
HYPOGAMMAGLOBULINEMIA
106
Polyclonal gammopathy ; 2 types of globulins are increased
Hepatic cirrhosis
107
Negative predictor of AMI ; oxygen-carrying protein in skeletal and cardiac muscles ; detected SOONER that’s TROPONIN but NOT CARDIAC SPECIFIC
Myoglobin
108
Gold standard for acute myocardial infarction ; CARDIAC SPECIFIC and show SUSTAINED ELEVATION
Cardiac troponins
109
Troponin with greater cardiac specificity
Troponin I
110
Used as markers for coronary heart failure ; structurally related neurohormones that affect body fluid homeostasis and blood pressure
BNP (brain natriuretic peptide) an NT-proBNP (N-terminal-pro BNP)
111
Endogenous marker of GFR
Cystatin C and B-trace protein
112
Useful in cases where creatinine measurement is not appropriate
Cystatin C
113
Correlates with serum cystatin C and urine micro proteins ; not influenced by glucocorticoid therapy
B trace proteins
114
Biomarker of bacteremia or sepsis ; increases early in infection (3-6 hours) and has a greater specificity for infection than CRP
PROCALCITONIN
115
Early predictor of acute kidney infection
Neutrophil gelatinase-associated lipocalin
116
Marker for nutritional status ; demonstrates a wide variety of cellular interactions, e.g. cell adhesion, differentiation, growth, and wound healing
Fibronectin
117
Low value of this protein marker is associated with increased risk of metabolic syndrome ; inversely correlated with BMI
Adiponectin
118
Biochemical marker of bone resorption (osteoporosis) ; proteolyic fragments of collagen I
Cross-linked C telopeptides
119
Biomarkers of Alzheimer’s disease
Neuronal thread protein, amyloid b42, Tau protein
120
Ultimate reference method based on the measurement of nitrogen content (!6%)
Kjeldahl method
121
Measurement of refractive index due to proteins in solution
Refractometry
122
Measurement of the change in optical density following precipitation with TCA, SSA, benzalkonium chloride
Turbidimetry
123
UV absorption : measurement of protein absorbance at ____ nm owing mostly to ________
280 nm ; tryptophan, tyrosine, phenylalanine
124
Detection o peptide bond forming a violet color (540 nm)
Biuret method
125
Oxidation of phenolic groups producing a DEEP BLUE color
Folin-Ciocalteau (Lowry) method
126
Formation of violet color in the presence of amino groups
Ninhydrin method
127
Measurement of the shift in absorbance when proteins bind to a dye
Dye-binding technique
128
Dye used for total protein
Coummassie brilliant blue
129
Dye used for albumin : nonspecific (globulins may also bind)
Methyl orange
130
Dye used for albumin : less sensitive ; subject to interferences
2,4-HABA
131
Dye used for albumin : most commonly used dye
Bromcresol green
132
Dye used for albumin : specific, sensitive, precise
Bromcresol purple
133
Protein reference value : total protein, ambulatory
6.5-8.3 g/dL
134
Albumin reference value :
3.5 - 5.5 g/dL
135
A/G ratio formula
Albumin / Total protein - Albumin
