NPNs Flashcards
1
Q
urea is the product of what
A
product of protein and amino acid catabolism
2
Q
what is the major excretory product of protein metabolism
A
urea
3
Q
urea are formed from ___ and ___ generated during protein catabloism
A
amino groups, free ammonia
4
Q
what is the major nitrogen that contains the metabolic product of protein catabolism
A
urea
5
Q
catabolism reactions that form urea are carried out by what
A
hepatic enzymes in the liver
6
Q
urea is excreted via
A
the kidneys, can also be through skin and GIT
7
Q
clinical applications of urea
A
evaluate renal function
assess hydration status
determine nitrogen balance
aid in diagnosis of renal disease
verify adequacy of dialysis
8
Q
increased urea indicates what
A
kidneys are not working properly
9
Q
increase protein intake may elevate
A
urea
10
Q
urea enzymatic method
A
urease reaction
coupled method
second coupled method
11
Q
end product of urease reaction
A
2NH4 + CO3
12
Q
dry chemistry systems are used in
A
automated systems
multilayer film reagents
dry reagent strips
13
Q
a semipermeable membrane separates the first stage of the reaction involving urease, and ammonia is detected by using a simple pH indicator reaction
A
dry chemistry systems
14
Q
dry chemistry systems formula (urea)
A
ammonia + pH indicator = color change
15
Q
this urea determination is specific and rapid
A
conductimetric
16
Q
in conductimetric, conversion of — to — and — results in increased conductivity (urea)
A
unionized urea to NH4 and CO3
17
Q
what is the test for spectrophotometric method in urea
A
Berthelot reaction
18
Q
end product of Berthelot reaction (urea) that will be measured by the spectrophotometer
A
indophenol
19
Q
what are the three enzymatic methods for urea
A
urease reaction
coupled method
second coupled method
20
Q
what enzymes are used in coupled method (urea)
A
urease
glutamate dehydrogenase
21
Q
what is measured for coupled method (urea enzymatic method)
A
rate of disappearance of nicotinamide adenine dinucleotide
22
Q
what nm is coupled method measured
A
340nm
23
Q
reference method for urea determination
A
coupled method
24
Q
end product of second coupled method
A
quinone-monoamine dye
25
chemical method for urea
Fearon reaction
26
relationship of color intensity and quantity of urea
directly proportional
27
what nm is Fearon reaction read
540nm
28
what is added to urea in Fearon reaction
diacetyl monoxime
29
term for increased urea in blood
azotemia
30
3 types of azotemia and its causes
PRE-RENAL (problems in circulation
-heart problems (CHF)
-decreased renal blood flow (hypovolemia)
-increased protein
-dehydration
-shock, fever, hemorrhage
RENAL
-kidney disease
-glomerulonephritis
-tubular necrosis
-nephropathy
-uremia (urea in blood with renal failure)
POST-RENAL
-urinary tract obstruction: urea--->blood
-kidney stone
-UT and prostate tumors
-infections
31
creatinine is symthesized in
the liver, kidneys, and pancreas
32
creatinine is synthesized from
arginine, glycine, and methionine
33
transamidation forms (creatinine)
guanidino acetic acid
34
methylation of guanidino acetic acid is via the
activity of S-adenosyl methionine
35
creatine is transported to --- and will be converted to ---
muscles, creatine phosphate (phosphocreatine)
36
creatine phosphate loses --- and creatine loses --- to form ---
phosphoric acid, water, creatinine
37
it is the cyclic anhydride of creatine
creatinine
38
what is the final product of decomposition of phosphocreatine
creatinine
39
what is the final product of decomposition of proteins
urea
40
creatinine is released into the circulation at a --- rate and is proportional to the ---
relatively constant rate, individual's muscle mass
41
creatinine is --- by the glomerulus and small amounts is secreted by the PCT
freely filtered
42
what substance tested is preferred for renal function and reason behind
creatinine because it is excreted fully unlike urea that some are still reabsorbed
43
this is used to measure the completeness of 24-hour urine collection
creatinine
44
clinical applications of creatinine
assess kidney function
assess severity and progression of kidney damage
measure the completeness of 24hr urine collection
effectiveness of dialysis
45
list of chemical methods for creatinine
Jaffe reaction
Kinetic assays (Kinetic Jaffe method)
Jaffe with adsorbent
46
Jaffe reaction is based on the activity of creatinine when reacted with an ---
alkaline picrate
47
temperature required for Jaffe reaction
25C
48
wavelength for Jaffe reaction
485nm or 490-500nm
49
this method for creatinine is non-specific
Jaffe reaction
50
this chemical method for creatinine has an improved specificity and duration
kinetic assays (Kinetic Jaffe method)
51
kinetic assays (kinetic Jaffe method) is used in
automated methods
wet chemistry analytical systems
52
this test gives more accurate results when creatinine in a protein-free filtrate is adsorbed into --- and ---
Jaffe with adsorbent
Fuller's earth reagent
Lloyd's reagent
53
composition of Fuller's earth reagent and Lloyd's reagent
aluminum magnesium silicate
sodium aluminum silicate
54
in Jaffe adsorbent method, the mixture is eluted and reacted with ---
alkaline picrate
55
true or false: Jaffe with adsorbent method is rapid and specific
false, it is time consuming but is specific because it is an enzymatic mehtod
56
what are the enzymatic methods for creatinine
creatininase (creatine amidohydrolase)
creatininase and creatinase (creatine amidinohydrolase)
creatine deaminase (creatine imino-hydrolase)
57
other methods for creatinine
high performance liquid chromatography
isotope dilution mass spectrophotometry
58
required specimen for urea and creatinine
serum, plasma, urine
59
true or false: fasting specimen is needed for urea and creatinine
false, it is not required since these are already waste products
60
what specimens should be avoided in testing creatinine
hemolyzed specimen, icteric samples, lipemic samples
61
a measure of the amount of creatinine eliminated from the blood by the kidneys
creatinine clearance
62
define glomerular filtration rate
volume of plasma filtered by the glomerulus per unit of time
63
most common error in creatinine clearance
incorrect timing
64
these causes increased creatinine clearance
high cardiac output
pregnancy
burns
carbon monoxide poisoning
65
these causes decreased creatinine clearance
impaired kidney function
dehydration
hemorrhage
CHF
66
this method for creatinine is prone to interferences (what are these interferences and how to minimize)
creatininase and creatinase (creatine amidinohydrolase)
-bilirubin: +potassium ferricyanide or bilirubin oxidase
-ascorbic acid: +ascorbic oxidase
67
this creatinine method is used in point of care testing
creatininase and creatinase (creatine amidinohydrolase)
68
uric acid is the result of
purine degredation
68
it is the ionized form of uric acid
urates
68
purine nucleotides are synthesized and degraded in all tissues but urate is produced only in tissues with --- which can be found primarily in the ---
xanthine oxidase in liver and small intestines
69
true or false: urates are nearly or completely unbound to a plasma protein
true
69
urates predominates in what samples
plasma, extracellular fluid, synovial fluid
69
this percentage of urates exists as --- at pH ---
98% exists as monosodium urate at pH 7.4
70
production of uric acid is dependent on the
purine content of diet
rate of purine biosynthesis, degredation, and salvage
71
this amount of uric acid is excreted by the kidneys, and the rest of it is excreted via the ---
2/3-3/4 excreted by kidney, the rest via the GIT
72
increased uric acid causes what diseases
gout arthritis, kidney stones, formation of crystals
73
in general, what foods causes high uric acid
foods that have more cells (meat, etc)
more cells=more purines
74
urates are filtered by the --- and secreted by the ---
glomerulus, DCT
75
urates are cleared from the plasma via the activities of
organic anion transporters
76
what transporters are located in the basolateral membrane of the PCT
OAT1 (SLC22A6)
OAT2 (SLC22A7)
OAT3 (SLC22A8)
77
what transporters are located in the apical brush-border membrane of PCT
OAT4 (SLC22A11)
OAT10 (SLC22A13)
URAT (SLC22A12)
78
OATs 1, 2, and 3 facilitates the movement of urates from --- to the --- in exchaneg with some ---
from interstitium to the cell cytosol in exchange with decarboxylates
79
OATs 4, 10, and URAT carries urate and other organic anions into the --- from the --- in exchange for ---
into the tubular cells from the lumen in exchange for intracellular organic anions
80
counter ions include
chloride
lactate
pyrazinoate
nicotinate
81
once inside the cell, urates must pass to the basolateral side of the lumen in a process controlled by --- like ---
voltage-dependent carriers like GLUT9
82
these transporters of urates facilitates movement from renal epithelial cells to the renal interstitium
OAT4, OAT10, URAT
83
main purpose for testing uric acid
confirm diagnosis and monitor treatment of gout
others include:
-prevent UA nephropathy during chemotherapeutic treatment
-assess inherited disorders of purine metabolism
-detect kidney dysfunction
84
enzymatic method for uric acid determination
uricase method
85
sources of uricase (urate oxidase)
aspergillus flavus
candida utilis
bacillus fastidious
hog liver
86
it is an oxireductase
uricase (urate oxidase)
87
hydrogen peroxide in uricase method is measured using
horseradish peroxidase and an oxygen acceptor
list of oxygen acceptors:
-4-aminophenazone
-3-methyl-1-benzothiazoline-hydrazone
-2,2-azino-di-(3-ethyl benzathiazoline)-6-sulfate
-O-dianisidine
88
which is more specific for uric acid determination: uricase method or phosphotungstic acid method
uricase method
89
uricase method measures different absorption of --- and --- at ---nm
uric acid, allantoin, 293nm
90
interferences in uricase method
proteins
hgb
xanthine
bilirubin
ascorbic acid
91
chemical method for uric acid determination
phosphotungstic acid method (Caraway method)
92
PTA requires this kind of specimen
protein free serum or plasma (requires deproteinization step)
93
PTA is read at ---nm
700nm
94
other methods used for UA determination
high performance liquid chromatography
isotope dilution mass spectrophotometry
95
specimen requirements for UA test
urine, serum, or heparinized plasma
EDTA and fluoride should not be used in uricase method
avoid lipemia, bilirubin, and hemolysis
96
true or false: UA test needs fasting
false, recent meals have no effect
97
associated diseases for hyperuricemia
gout
leukemia
megaloblastic and hemolytic anemia
tophi
98
associated diseases in hypouricemia
severe liver disease
allopurinol overdose
99
final product in uricase method
allantoin + CO2 + H2O2
100
what is added to uric acid in uricase method
H2O2 + O2
101
end products of PTA method
allantoin + CO2 + tungsten blue
102
at what nm is creatininase is read
340 nm
103
this creatinine method requires large sample
creatininase
