Author Archives: sentrallab

Urin, total protein (U-protein)

Engelsk navn:Urine, total protein
Reagensprodusent:Siemens Healthcare Diagnostics Inc.
Analyseprinsipp:This method is an endpoint chemistry. It is based on the measurement of the shift in absorption that occurs when pyrogallol red-molybdate complex binds with protonated basic amino groups of proteins at an acidic pH. The increase in absorbance at 596/694 nm is proportional to protein concentration in the sample.
Metoden tatt i bruk: 28.02.08
Referanse:1.Tietz NW. Clinical Guide to Laboratory Tests. 3rd ed. Philadelphia, PA: WB Saunders Company; 1995:520-521.
2.Fujita Y, Mori I, Kitano S. Color Reaction between Pyrogallol Red-Molybdenum Complex and Protein. Bunseki Kagaku 1983;32:E379-E386.
3.Orsonneau JL, Douet P, Massoubre C, et al. An improved pyrogallol red-molybdate method for determining total urinary protein. Clin Chem 1989;35(11):2233-2236.
4.Henry RJ, Cannon DC, Winkelman JW. Clinical Chemistry, Principles and Techniques. 2nd ed. Harper & Row; 1974.
5.Young DS. Effects of Drugs on Clinical Laboratory Tests. 5th ed. Washington, DC:AACC Press; 2000.
6.Clinical and Laboratory Standards Institute (formerly NCCLS). Evaluation of Precision Performance of Quantitative Measurement Methods; Approved Guideline – Second Edition. Wayne, PA: Clinical and Laboratory Standards Institute; 2004. NCCLS Document EP05-A2.

Urinsyre (UA)

Engelsk navn:Uric Acid
Reagensprodusent:Siemens Healthcare Diagnostics Inc.
The uric acid is converted by uricase to allantoin and hydrogen peroxide. A coloured complex is formed from hydrogen peroxide, 4-aminophenazone and TOOS [N-ethyl-N-(2-hydroxy-3-sulfopropyl)-3-methylaniline] under the catalytic influence of peroxidase. The abosorbance of the complex is measured as an endpoint reaction at 545 nm.
Metoden tatt i bruk: 01.07.01
Referanse:1.Fossati P, Prencipe L and Berti G : Use of 3,5-dichloro-2-hydroxybenzenesulfonic acid / 4-aminophenazone chromogenic system in direct enzymic assay of uric acid in serum and urine.
Clin Chem 26(2): 227-231 (1980)
2.Trinder P: Determination of glucose in blood using glucose oxidase-peroxidase system with a non-carcinogenic chromogen.
J Clin Pathol 22: 158-161 (1969)
3.Tietz, NW: Clinical Guide to Laboratory Tests, 3rdEdition
WB Saunders Company, Philadelphia, PA pp 624-625 (1995)

Urea (Urea)

Engelsk navn:Urea Nitrogen
Reagensprodusent:Siemens Medical Solutions Diagnostics
Analyseprinsipp:Enzymatic: urease with GLDH
The urea is hydrolysed in the presence of water and urease to produce ammonia and carbon dioxide. The ammonia reacts with 2-oxoglutarate in the presence of glutamate dehydrogenase and NADH. The oxidation of NADH to NAD is measured as an inverse rate reaction at 340 nm.
(Metoden tatt i bruk: 1/7-01)
Referanse:1.Roch-Ramel F : An enzymatic and fluorophotometric method for estimating urea concentrations in nanoliter specimens.
Anal Biochem 21: 372-381 (1967
2.Tietz, NW: Clinical Guide to Laboratory Tests, 3rd Edition
WB Saunders Company, Philadelphia, PA pp 622-624 (1995)

Tyroksin, fritt (FT4, fritt T4) (hund)

Engelsk navn:Free T4, (Canine)
Analyseinstrument:IMMULITE® 2000
Reagensprodusent:Siemens Medical Solutions Diagnostics
Analyseprinsipp:Free T4 is a solid-phase, chemiluminescent, competitive analog immunoassay.For detailed description:
IMMULITE® 2000; Principles of operation 

Free T4 procedure is a direct or single test assay, in the sense that its results are not calculated as a function of total T4, but interpolated from a (stored) standard curve calibrated in terms of free T4 concentrations. In this respect it differs from classic equilibrium dialysis methods and from so-called free T4 index determinations as well. It requires neither a pre-incubation step nor preliminary isolation of the free fraction by dialysis or column chroma-tography. The assay employs several features to preserve the equilibrium between free and protein-bound T4 and to measure accurately the unbound fraction. First, optimal concentrations of blocking agents prevent ligand-labeled T4 analog from binding to endogenous proteins (including albumin) while maintaining native T4 binding characteristics. The blocking agents also minimize artifacts arising from abnormal levels of albumin or free fatty acids. Second, the T4 analog has a nondetectable binding affinity for TBG. Third, the assay’s specific antibody binds T4 about as tightly as albumin binds T4 and thereby avoids stripping the hormone from thyroid binding proteins. Finally, the procedure operates at physiological temperature, pH and ionic strength.(Metoden tatt i bruk: 8/3-04)

Referanse:1.Hay ID, Bayer MF, et al. American Thyroid Association assessment of current free thyroid hormone and thyrotropin measurements and guidelines for future clinical assays. Clin Chem 1991;37:2002-8.
2.Lindstedt G, et al. Clinical use of laboratory thyroid tests and investigations. JIFCC 1994;6:136-41.
3.Mandel SJ, Brent GA, Larsen PR. Levothyroxine therapy in patients with thyroid disease. Ann Intern Med 1993;119:492-502.
4.Singer PA, Cooper DS, etal. Treatment guidelines for patients with
hyperthyroidism and hypothyroidism. JAMA 1995;273:808-12.
5.Witherspoon LR, El Shami AS, et al. Chemically blocked analog assays for
free thyronines. Clin Chem 1988;34:9–16 and 17–23.
6.Wosilait WD. A theoretical analysis of the distribution of thyroxine among sites on thyroid binding globulin, thyroid binding prealbumin and serum albumin. Res Commun Chem Pathol Pharmacol 1977;16:541–8.

Tyroksin, total (TT4, total T4)

Engelsk navn:Total T4
Analyseinstrument:IMMULITE® 2000
Reagensprodusent:Siemens Medical Solutions Diagnostics
Analyseprinsipp:Total T4 is a solid-phase, chemiluminescent competitive immunoassay.
For detailed description: IMMULITE® 2000; Principles of operation(Metoden tatt i bruk: 8/3-04)
Referanse:1.lshaw BE, Rijnberk A. Radioimmunoassay of plasma T4 and T3 in the diagnosis of primary hypothyroidism in dogs. J Am Animal Hosp Assoc 1979;15:17-23.
2.Chastain CB. Canine pseudohypothyroidism and cover hypothyroidism. Probl Vet Med 1993;2:693-716.
3.Ekins RP. Remarks on radioimmunoassay specificity. In: Margoulies M, editor. Proteins and polypeptide hormones. Amsterdam: Excerpta Medica, 1969: 575-81.
4.Gaschen F, Thompson J, Beale K, Keisling K. Recognition of triiodothyronine-containing epitopes in canine thyroglobulin by circulating thyroglobulin autoantibodies. Am J Vet Res 1993;54(2):244-7.
5.Kaneko JJ. Thyroid Function. In: Kaneko JJ, editor. Clinical biochemistry of domestic animals. 3rd ed. New York: Academic Press, 1980: 491-512.
6.Kaptein EM, Moore GE, Ferguson DC, Hoenig M. Thyroxine and triiodothyronine distribution and metabolism in thyroxinereplaced athyreotic dogs and normal humans. Am J Physiol 1993;264:E90-E100.
7.Kubasik NP, et al. Neonatal hypothyroidism: assessment of a commercial kit for thyroxine radioimmunoassay. Clin Chem 1977;23:2174-5. March/Apr;7:2.
8.Kubasik NP, et al. Clinical evaluation of two thyrotropin radioimmunoassay kits: human serum matrix calibrators and bovine serum matrix calibrators. Clin Chem 1981;27:504-5
9.Lee DE, Lamb SV, Reimers TJ. Effects of hyperlipemia on radioimmunoassays for progesterone, testosterone, thyroxine and cortisol in serum and plasma samples from dogs. Am J Vet Res 1991;52(9):
10.Peterson M, Swerdloff RS. Separation of bound from free hormone in radioimmunoassay of lutropin and follitropin. Clin Chem 1979;25:1239-41.
11.Refetoff S. Thyroid function tests. In:DeGroot LJ, editor. Endocrinology. New York:Grune & Stratton, 1979;1:387-428.
12.Reimers TJ, Lamb SV, Bartlett SA, Matamoros RA, Cowan RG, Engle JS. Effects of hemolysis and storage on quantification of hormones in bloodsamples from dogs, cattle and horses. Am J Vet Res 1991;52(7):1075-80.
13.Reimers TJ, Lawler DF, Sutaria PM, Correa MT, Erb HN.Effects of age, sex, and body size on serum concentrations of thyroid and adrenocortical hormones in dogs. Am J Vet Res 1991;51(3):1489-91.
14.Siegel ET. Endocrine diseases of the dog. Philadelphia: Lea & Febiger, 1977: 54-80.
15.Thacker EL, Refsal KR, Bull RW. Prevalence of autoantibodies tothyroglobulin, thyroxine, or triiodothyronine and relationship of autoantibodies and serum concentrations of iodothyronines in dogs. Am J Vet Res 1992;53(4):449-53.
16.Wood WG, et al. A second external quality control survey from serum triiodothyronine (T3) and thyronine (T4) assays. J Clin Chem Clin Biochem 1980;18:511-9.
17.Clinical endocrinology: update on thyroid testing. Vet Ref Lab Newsletter 1983
18.Tietz NW, editor. Clinical guide to laboratory tests. 3rd ed. Philadelphia:W.B. Saunders, 1995: 596.

Tyreoglobulin antistoffer (TgAA)

Engelsk navn:Thyroglobulin Autoantibody
Analyseinstrument:Tecan Sunrise Absorbance Reader
Reagensprodusent:Oxford Laboratories, Inc
Analyseprinsipp:This indirect enzyme immunoassay is for the determination of Tg autoantibodies in canine serum. Purified canine Tg is coated on the wells of a 96-well polystyrene plate. Canine test sera, along with positive and negative canine control sera are added to the plate and allowed to bind. Enzyme labeled anti-immunoglobulin is then added and autoantibodies are allowed to incubate and bind. Enzyme substrate is then added and plate incubated. The higher the concentration of TgAA in the serum sample, the higher amount of substrate bound and the brighter the color. The reaction is terminated by the addition of stop solution.

(Metoden tatt i bruk: Mars 2009)

Referanse:1.Thacker EL, Davis JM, Refsal KR, Bull RW. Isolation of thyroid peroxidase and lack of autoantibodies to the enzyme in dogs with autoimmune thyroid disease. Amer J Vet Res 1995; 56(1): 34-38.
2.Nachreiner RF, Refsal KR, Graham PA, Hauptman J, Watson GL. Prevalence of autoantibodies to thyroglobulin in dogs with nonthyroidal illness. Amer J Vet Res 1998; 59(8): 951-55.

Triglyserider (Tg)

Engelsk navn:Triglycerides
Reagensprodusent:Siemens Medical Solutions Diagnostics
Analyseprinsipp:Enzymatic/Trinder without serum blank
The triglycerides are converted to glycerol and free fatty acids by lipoprotein lipase. The glycerol is then converted to glycerol-3-phosphate by glycerol kinase in the presence of glycerol-3-phosphate-oxidase to form hydrogen peroxidase. A coloured complex is formed from hydrogen peroxide,
4-aminophenazone and 4-chlorophenol under the catalytic influence of peroxidase. The absorbance of the complex is measured as an endpoint reaction at 505 nm.This procedure quantitates the total triglycerides including the mono and diglycerides and the free glycerol fractions.
(Metoden tatt i bruk: 1/7-01)
Referanse:1.Fossati P and Prencipe L : Serum triglycerides determined colorimetrically with an enzyme that produces hydrogen peroxide. Clin Chem 28 (10):2077 (1982)
2.Trinder P: Determination of glucose in blood using glucose oxidase with an alternative oxygen acceptor. Ann Clin Biochem 6: 24-27 (1969)
3.Tietz, NW: Clinical Guide to Laboratory Tests, 3rd Edition
WB Saunders Company, Philadelphia, PA pp 610-611 (1995)


Engelsk navn:Zinc
Analyseprinsipp:After deproteinizing zinc forms a red chelate with 5-Br-PAPS (2-[(5-Bromo-2-pyridylazo]-5-[N-propyl-N-(3-sulfopropyl)amino]phenol) at pH 7.5-9.5  The formation is measured at 545 nm.

(Metoden tatt i bruk: 1/7-01)

Referanse:1.M. Saito, T. Makino et al., Clinica Chimica Acta, 120 (1982) 127-135.
2.R. Homster, B. Zak, Clin. Chem. 31/8, 1310-1313 (1985).

SAA (Serum Amyloid A)

Engelsk navn:Serum Amyloid A
Reagensprodusent:Eiken Chemical Co., Tokyo, Japan
Analyseprinsipp:Anti SAA coated latex agglutination photometric immunoassay. SAA is a sensitive and rapid acute phase reactant for the monitoring of inflammatory diseases and assessing the prognosis.

(Metoden tatt i bruk: Januar 2009)

Referanse:1.Jacobsen S, Kjelgaard-Hansen M, Hagbard Petersen H, Jensen AL. Evaluation of a commercially available human serum amyloid A (SAA) turbidometric immunoassay for determination of equine SAA concentrations. The Veterinary Journal 2006; 172( 2): 315-19.
2.Hansen AE, Schaap MK, Kjelgaard-Hansen M. Evaluation of a Commercially Available Human Serum Amyloid A (SAA) Turbidimetric Immunoassay for Determination of Feline SAA Concentration. Vet Res Commun 2006; 30: 863–72.
3.Jacobsen S, Thomsen MH, Nanni S. Concentrations of serum amyloid A in serum and synovial fluid from healthy horses and horses with joint disease. Am J Vet Res 2006; 67(10): 1738-42.

Protein, total (Tprot)

Engelsk navn:Total Protein
Reagensprodusent:Siemens Medical Solutions Diagnostics
Protein peptide bonds interact with cupric ions to form a purple complex which is measured as an endpoint reaction at 545 nm.
(Metoden tatt i bruk: 25/11-02)
Referanse:1.Weichselbaum TE : An accurate and rapid method for the determination of proteins in small amounts of blood serum and plasma. Amer J Clin Path 16:40 (1946)
2.Tietz, NW: Clinical Guide to Laboratory Tests, 3rd Edition
WB Saunders Company, Philadelphia, PA pp 518-519 (1995)