Effect of albumin concentration on the assay of serum free thyroxin by equilibrium radioimmunoassay with labeled thyroxin analog (Amerlex Free T4).

1983 ◽  
Vol 29 (2) ◽  
pp. 321-325 ◽  
Author(s):  
N Amino ◽  
K Nishi ◽  
K Nakatani ◽  
H Mizuta ◽  
K Ichihara ◽  
...  
Keyword(s):  
Serum Albumin ◽  
Pregnant Women ◽  
Binding Proteins ◽  
Solid Phase ◽  
Albumin Concentration ◽  
Serum Concentrations ◽  
Serum Samples ◽  
Free T4 ◽  
Serum Free

Abstract Serum free thyroxin (FT4) in normal nonpregnant and pregnant subjects was measured by radioimmunoassay (RIA) with Amerlex FT4 RIA (Amersham International) and LiquiSol FT4 RIA (Damon Diagnostics) kits. Amerlex FT4 values in serum from pregnant women were lower than those in serum from nonpregnant women, but LiquiSol FT4 values were similar in serum from both groups. Amerlex FT4 values were directly correlated with the concentrations of albumin in serum and inversely correlated with those of thyroxin-binding globulin, but not with prealbumin concentrations. No significant correlations were observed between LiquiSol FT4 values and serum concentrations of thyroxin-binding proteins. Amerlex FT4 values were normal in patients with excess, deficient, or decreased thyroxin-binding globulin. Albumin added to serum samples increased Amerlex FT4 values but not LiquiSol FT4 values. Albumin inhibited the binding of labeled thyroxin analog to the solid-phase thyroxin antibody. These data indicate that the albumin concentration influences FT4 values as measured by an RIA involving a thyroxin analog and that Amerlex FT4 values should be carefully interpreted when the patient has an abnormal concentration of serum albumin.

scholarly journals Comparison Between Measured and Calculated Free Calcium Values at Different Serum Albumin Concentrations

2016 ◽  
Vol 8 (02) ◽  
pp. 071-076 ◽  
Author(s):  
Altaf Ahmad Mir ◽  
Bela Goyal ◽  
Sudip Kumar Datta ◽  
Saidaiah Ikkurthi ◽  
Arnab Pal
Keyword(s):  
Serum Albumin ◽  
Tertiary Care ◽  
Free Calcium ◽  
Albumin Concentration ◽  
Care Hospital ◽  
Serum Samples ◽  
Spectrophotometric Methods ◽  
Significant Difference ◽  
Clinical Biochemistry Laboratory ◽  
The One

ABSTRACT Introduction: Free ionic calcium is the metabolically active component of total calcium (TCa) in blood. However, most laboratories report TCa levels that are dependent on serum albumin concentration. Hence, several formulae have evolved to calculate free calcium levels from TCa after adjustment for albumin. However, free calcium can directly be measured using direct ion selective electrodes rather than spectrophotometric methods used in autoanalyzers. Objectives: This study compares the levels of free calcium obtained by measurement by direct ion selective electrode (ISE) and the one calculated as a function of TCa by formulae. Materials and Methods: A total of 254 serum samples submitted to clinical biochemistry laboratory of a tertiary care hospital were analyzed for total protein, albumin, and TCa by standard spectrophotometric methods and for free calcium by direct ISE. Three commonly used formulae viz. Orrell, Berry et al. and Payne et al. were used to calculate adjusted TCa. Calculated free calcium was obtained by taking 50% of these values. Results: A significant difference (P < 0.05) was observed between calculated free calcium by all the three formulae and measured free calcium estimated by direct ISE using paired t-test and Bland–Altman plots. Conclusion: Formulae for predicting free calcium by estimating TCa and albumin lacks consistency in prediction and free calcium should be evaluated by direct measurement.

Neonatal thyroxine screening by use of a single-tube solid-phase radioimmunoassay.

1978 ◽  
Vol 24 (10) ◽  
pp. 1755-1758 ◽  
Author(s):  
A B Bell ◽  
L H Coleman
Keyword(s):  
Mass Screening ◽  
Filter Paper ◽  
Coefficient Of Variation ◽  
Binding Proteins ◽  
Solid Phase ◽  
Serum Samples ◽  
Single Tube ◽  
Screening Programs ◽  
Quantitative Results ◽  
Solid Phase Radioimmunoassay

Abstract Filter paper discs saturated with dried blood can be used in the Immunotube solid-phase thyroxine radioimmunoassay. This assay utilizes polypropylene tubes to which antibody to thyroxine is covalently bound. The filter paper standards and samples are placed in the tubes, followed by an assay buffer that contains I125-labeled thyroxine and compounds to displace thyroxine from its binding proteins. After incubation, bound and free thyroxine are separated by aspirating or decanting the disc and buffer from the tube. The test can be used with 0.32 cm (1/8 inch) or 0.64 cm(1/4 inch) discs, and gives quantitative results that correlate well with those for serum samples. The intra-assay coefficient of variation is less than 10%. The assay may readily be mechanized with existing disc-punching equipment, and results of its use in mass screening programs are described.

Free triiodothyronine and free thyroxin in sera of pregnant women and subjects with congenitally increased or decreased thyroxin-binding globulin.

1983 ◽  
Vol 29 (8) ◽  
pp. 1527-1530 ◽  
Author(s):  
J A Franklyn ◽  
M C Sheppard ◽  
D B Ramsden ◽  
R Hoffenberg
Keyword(s):  
Pregnant Women ◽  
Binding Proteins ◽  
Free Triiodothyronine ◽  
Free T4 ◽  
Free T3 ◽  
Low Concentrations ◽  
Euthyroid Status ◽  
In Pregnancy

Abstract Concentrations of free thyroxin (T4) and free triiodothyronine (T3) were measured in sera from pregnant women, in subjects with congenitally increased or decreased thyroxin-binding globulin (TBG), and in euthyroid controls. Measured free hormone concentrations were compared with calculated values for free hormone derived from concentrations of total T4, total T3, and binding proteins. Measured and calculated concentrations of free T4 and free T3 were below normal in the pregnant subjects but were normal in subjects with congenital increases of TBG. The low concentrations of free hormone in pregnancy are at variance with the euthyroid status of these subjects. Measured free T4 was normal, but concentrations of free T3 were less in the euthyroid congenitally low-TBG group.

Effect of serum albumin concentration on free thyroxin (Amerlex FT4) values in healthy non-pregnant and pregnant women

1988 ◽  
Vol 176 (2) ◽  
pp. 225-226 ◽  
Author(s):  
Shigeki Sakata ◽  
Takashi Komaki ◽  
Shin-ichiro Shiraki ◽  
Nobuko Kumasaki ◽  
Hirotoshi Iwata
Keyword(s):  
Serum Albumin ◽  
Pregnant Women ◽  
Albumin Concentration ◽  
Serum Albumin Concentration

scholarly journals Comparison of Liver Function Tests in Normal Pregnancy with Non-pregnant Matched Controls

2020 ◽  
Vol 33 (1) ◽  
pp. 17-24
Author(s):  
M Rokeya Khatun ◽  
Amina Khatun ◽  
Md Nowshad Ali
Keyword(s):  
Liver Function ◽  
Serum Albumin ◽  
Pregnant Women ◽  
Liver Function Tests ◽  
Albumin Concentration ◽  
Third Trimester ◽  
Serum Globulin ◽  
College Hospital ◽  
Cross Sectional ◽  
Function Tests

Background: Change of liver biochemical profiles is normal during pregnancy. It is almost impossible to understand disease processes that can threaten women during pregnancy without understanding normal physiological change. Aim of this study is to evaluate changes in serum liver function tests in normal pregnant women in first, second and third trimester. Material and Methods: The cross-sectional comparative study was carried out in the Department of Obstetrics & Gynaecology of Rajshahi Medical College Hospital, Bangladesh in 2019. This study consists of 90 pregnant women and 90 matched control. Among the 90 pregnant women, 30 were in first trimester, 30 were in second trimester and 30 were in third trimester. Blood samples were taken for routine liver function and protein profiles Results: Serum total and direct bilirubin concentrations were significantly lower in second and third trimester. The mean ALP level was slightly increased in 2nd trimester and drastically increased in 3rd trimesters during pregnancy. Serum ALT and AST activity was significantly increased in third trimester. No significant change in serum total proteins concentration, but serum albumin concentration was significantly lower and serum globulin concentration was significantly higher in all three trimester. Serum albumin/globulin ratio was significantly reduced in second and third trimester. Conclusion: Relative values of various liver function tests during gestational trimesters appear to be the best guide to confirm the diagnosis and treatment strategies. Thus, gynecologists should routinely monitor liver function tests in all gestational trimesters to avoid the future complications to mother and offspring. TAJ 2020; 33(1): 17-24

scholarly journals Significance of serum branched-chain amino acid to tyrosine ratio measurement in athletes with high skeletal muscle mass

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Katsuhiko Tsunekawa ◽  
Ryutaro Matsumoto ◽  
Kazumi Ushiki ◽  
Larasati Martha ◽  
Yoshifumi Shoho ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Amino Acid ◽  
Serum Albumin ◽  
Muscle Mass ◽  
Skeletal Muscle Mass ◽  
Albumin Concentration ◽  
Serum Albumin Concentration ◽  
Serum Concentrations ◽  
Hypermetabolic State ◽  
Branched Chain

Abstract Background Few nutritional markers reflect the hypermetabolic state of athletes with high levels of skeletal muscle. Although branched-chain amino acids (BCAA) play crucial roles in protein metabolism in skeletal muscle, the relationship between skeletal muscle mass and amino acid imbalances caused by the metabolism of BCAA and aromatic amino acids remains unclear. The aim of this study is to test the hypothesis that athletes with high levels of skeletal muscle mass have plasma amino acid imbalances, assessed by serum BCAA to tyrosine ratio (BTR) which can be measured conveniently. Methods The study enrolled 111 young Japanese men: 70 wrestling athletes and 41 controls. None of them were under any medications, extreme dietary restrictions or intense exercise regimens. Each participant’s body composition, serum concentrations of albumin and rapid turnover proteins including transthyretin and transferrin, BTR, and thyroid function were assessed. Results Compared to the controls, the athletes had significantly higher skeletal muscle index (SMI) (p < 0.001), and lower serum albumin concentration (p < 0.001) and BTR (p < 0.001). Kruskal–Wallis tests showed that serum albumin concentration and BTR were significantly lower in the participants with higher SMI. Serum albumin concentration and BTR were inversely correlated with SMI by multiple regression analysis (logarithmic albumin, β = − 0.358, p < 0.001; BTR, β = − 0.299, p = 0.001). SMI was inversely and transthyretin was positively correlated with serum albumin (SMI, β = − 0.554, p < 0.001; transthyretin, β = 0.379, p < 0.001). Serum concentration of free 3,5,3′-triiodothyronine (FT3) was inversely correlated with BTR, and, along with SMI and albumin, was independent predictor of BTR (SMI, β = − 0.321, p < 0.001; FT3, β = − 0.253, p = 0.001; logarithmic albumin, β = 0.261, p = 0.003). However, FT3 was not correlated with SMI or serum albumin. Serum concentrations of rapid turnover proteins were not correlated with BTR. Conclusions Increased skeletal muscle mass enhances the circulating amino acid imbalances, and is independently facilitated by thyroid hormones. Serum BTR may be a useful biomarker to assess the hypermetabolic state of wrestling athletes with high levels of skeletal muscle.

scholarly journals Two novel rat liver membrane proteins that bind advanced glycosylation endproducts: relationship to macrophage receptor for glucose-modified proteins.

1991 ◽  
Vol 174 (3) ◽  
pp. 515-524 ◽  
Author(s):  
Z Yang ◽  
Z Makita ◽  
Y Horii ◽  
S Brunelle ◽  
A Cerami ◽  
...  
Keyword(s):  
Membrane Proteins ◽  
Serum Albumin ◽  
Rat Liver ◽  
Binding Proteins ◽  
Solid Phase ◽  
Raw 264.7 ◽  
Liver Membrane ◽  
Monocytes And Macrophages ◽  
Modified Proteins ◽  
Advanced Glycosylation

Advanced glycosylation endproducts (AGEs), the glucose-derived adducts that form nonenzymatically and accumulate on tissue proteins, are implicated in many chronic complications associated with diabetes and aging. We have previously described a monocyte/macrophage surface receptor system thought to coordinate AGE protein removal and tissue remodeling, and purified a corresponding 90-kD AGE-binding protein from the murine RAW 264.7 cell line. To identify AGE-binding proteins in normal animals, the tissue distribution of 125I-AGE rat serum albumin taken up from the blood was determined in rats in vivo. These uptake studies demonstrated that the liver was a major site of AGE protein sequestration. Using a solid-phase assay system involving the immobilization of solubilized membrane proteins onto nitrocellulose to monitor binding activity, and several purification steps including affinity chromatography over an AGE bovine serum albumin matrix, two rat liver membrane proteins were isolated that specifically bound AGEs, one migrating at 60 kD (p60) and the other at 90 kD (p90) on SDS-PAGE. NH2-terminal sequence analysis revealed no significant homology between these two proteins nor to any molecules available in sequence databases. Flow cytometric analyses using avian antibodies to purified rat p60 and p90 demonstrated that both proteins are present on rat monocytes and macrophages. Competition studies revealed no crossreactivity between the two antisera; anti-p60 and anti-p90 antisera prevented AGE-protein binding to rat macrophages when added alone or in combination. These results indicate that rat liver contains at least two novel and distinct proteins that recognize AGE-modified macromolecules, although p90 may be related to the previously described 90-kD AGE receptor isolated from RAW 264.7 cells. The constitutive expression of AGE-binding proteins on rat monocytes and macrophages, and the sequestration of circulating AGE-modified proteins by the liver, provides further evidence in support of a role for these molecules in the normal removal of proteins marked as senescent by accumulated glucose-derived covalent addition products, or AGEs.

scholarly journals Serum Albumin and the Specificity of Free Tri-Iodothyronine as a Test for Hypothyroidism

1989 ◽  
Vol 26 (3) ◽  
pp. 233-237 ◽  
Author(s):  
D J Wright ◽  
L Biddulph ◽  
M G Rinsler
Keyword(s):  
Serum Albumin ◽  
Old Age ◽  
Normal Population ◽  
Close Correlation ◽  
Acute Illness ◽  
Bromocresol Green ◽  
Albumin Concentration ◽  
Serum Albumin Concentration ◽  
Serum Free ◽  
Chemical Evidence

Serum free tri-iodothyronine (FT3), using two different radioimmunoassays, and serum albumin, using bromocresol green dye-binding method, were measured prospectively in 1374 adults investigated for thyroid disease. The results of similar pairs of measurements in 6608 serum specimens obtained from adults, but using one of the radioimmunoassays for FT3, were examined retrospectively. A close correlation was observed between the FT3 values and serum albumin concentration. Normalisation of the FT3 level using a standard albumin value of 43 g/L in the absence of chemical evidence of hypothyroidism (serum thyrotrophin <6·5 mIU/L) gave a distribution of FT3 values which closely resembled that from a normal population. The effects of acute illness and old age, which may lower the FT3 value, can be corrected by this transformation.

Continuous-flow serum albumin determination by reaction with picrate ions, with use of a flow-through picrate ion electrode.

1981 ◽  
Vol 27 (3) ◽  
pp. 427-430 ◽  
Author(s):  
E P Diamandis ◽  
D S Papastathopoulos ◽  
T P Hadjiioannou
Keyword(s):  
Serum Albumin ◽  
Continuous Flow ◽  
Peak Height ◽  
Ion Concentration ◽  
Screening Tests ◽  
Albumin Concentration ◽  
Serum Samples ◽  
Factors Affecting ◽  
Analytical Recovery ◽  
Flow Through

Abstract An automated potentiometric method for serum albumin determination by use of the picrate/albumin reaction is described. A continuous-flow system and a specially designed flow-through picrate ion electrode were used in making the measurements. Various factors affecting the reaction, such as pH, picrate ion concentration, and reaction time, were studied. Peak height in millivolts and albumin concentration were linearly related in the range 10-70 g/L. Both within-run and day-to-day, the CV for the method was about 2%. Analytical recovery of albumin added to serum samples ranged from 97.0 to 110.3%, averaging 102.2%. Results compare favorably with those by the established bromcresol green method. The proposed method is suitable for routine use and for screening tests.

Sign in / Sign up

Export Citation Format

Share Document