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Pierre D Delmas - One of the best experts on this subject based on the ideXlab platform.

  • assessment of the serum levels of bone alkaline phosphatase with a new Immunoradiometric Assay in patients with metabolic bone disease
    The Journal of Clinical Endocrinology and Metabolism, 1993
    Co-Authors: Patrick Garnero, Pierre D Delmas
    Abstract:

    We measured serum bone alkaline phosphatase (B-ALP) with a new Immunoradiometric Assay (IRMA) in a large sample of healthy controls comprising 173 women and 180 men, 20-88 yr of age, and in patients with metabolic bone disease. Using serum samples from patients with liver disease and patients with Paget's disease with elevated total alkaline phosphatase (T-ALP) as a source of, respectively, liver and bone isoenzymes, we determined a liver cross-reactivity of the IRMA of 16% that was confirmed by electrophoresis of the circulating alkaline phosphatase isoenzymes. The IRMA was linear for serial sample dilutions, the recovery ranged from 89-110%, and the intra- and interAssay variations were below 7% and 9%, respectively. B-ALP increased linearly with age in both sexes, and the mean B-ALP serum levels were not significantly different for women and men (11.3 +/- 4.8 ng/mL for women; 11.0 +/- 4.0 ng/mL for men). The increase in B-ALP after the menopause was significantly higher than that in T-ALP (+77% vs. +24...

  • assessment of the serum levels of bone alkaline phosphatase with a new Immunoradiometric Assay in patients with metabolic bone disease
    The Journal of Clinical Endocrinology and Metabolism, 1993
    Co-Authors: Patrick Garnero, Pierre D Delmas
    Abstract:

    We measured serum bone alkaline phosphatase (B-ALP) with a new Immunoradiometric Assay (IRMA) in a large sample of healthy controls comprising 173 women and 180 men, 20-88 yr of age, and in patients with metabolic bone disease. Using serum samples from patients with liver disease and patients with Paget's disease with elevated total alkaline phosphatase (T-ALP) as a source of, respectively, liver and bone isoenzymes, we determined a liver cross-reactivity of the IRMA of 16% that was confirmed by electrophoresis of the circulating alkaline phosphatase isoenzymes. The IRMA was linear for serial sample dilutions, the recovery ranged from 89-110%, and the intra- and interAssay variations were below 7% and 9%, respectively. B-ALP increased linearly with age in both sexes, and the mean B-ALP serum levels were not significantly different for women and men (11.3 +/- 4.8 ng/mL for women; 11.0 +/- 4.0 ng/mL for men). The increase in B-ALP after the menopause was significantly higher than that in T-ALP (+77% vs. +24%; P < 0.001). When the values of postmenopausal women were expressed as the SD from the mean of premenopausal women, the mean Z scores were 2.2 +/- 1.8 for B-ALP and 0.9 +/- 1.3 for T-ALP (P < 0.001 between the two). Serum B-ALP was increased from control values in patients with Paget's disease (n = 57; mean, 171.8 +/- 135.6 ng/mL; P < 0.001), in patients with primary hyperparathyroidism (n = 18; mean, 17.2 +/- 5.9 ng/mL; P < 0.001), and in patients with chronic renal failure on hemodialysis (n = 83; mean, 36.6 +/- 35.7 ng/mL; P < 0.001). In patients with Paget's disease, B-ALP was highly correlated with T-ALP (r2 = 0.94; P < 0.001), and the decrease in its serum level was larger than that in T-ALP after treatment with the bisphosphonate pamidronate (-58% vs. -43%; P < 0.03). In patients with various liver diseases, B-ALP was slightly increased, but stayed within the normal range (mean +/- 2 SD) until T-ALP did not exceed 4.5 mu katal/L. We conclude that this new IRMA for B-ALP is reliable, has a low cross-reactivity with the liver isoenzyme, and appears to be more sensitive than T-ALP for the clinical investigation of patients with osteoporosis and other metabolic bone diseases.

Patrick Garnero - One of the best experts on this subject based on the ideXlab platform.

  • assessment of the serum levels of bone alkaline phosphatase with a new Immunoradiometric Assay in patients with metabolic bone disease
    The Journal of Clinical Endocrinology and Metabolism, 1993
    Co-Authors: Patrick Garnero, Pierre D Delmas
    Abstract:

    We measured serum bone alkaline phosphatase (B-ALP) with a new Immunoradiometric Assay (IRMA) in a large sample of healthy controls comprising 173 women and 180 men, 20-88 yr of age, and in patients with metabolic bone disease. Using serum samples from patients with liver disease and patients with Paget's disease with elevated total alkaline phosphatase (T-ALP) as a source of, respectively, liver and bone isoenzymes, we determined a liver cross-reactivity of the IRMA of 16% that was confirmed by electrophoresis of the circulating alkaline phosphatase isoenzymes. The IRMA was linear for serial sample dilutions, the recovery ranged from 89-110%, and the intra- and interAssay variations were below 7% and 9%, respectively. B-ALP increased linearly with age in both sexes, and the mean B-ALP serum levels were not significantly different for women and men (11.3 +/- 4.8 ng/mL for women; 11.0 +/- 4.0 ng/mL for men). The increase in B-ALP after the menopause was significantly higher than that in T-ALP (+77% vs. +24...

  • assessment of the serum levels of bone alkaline phosphatase with a new Immunoradiometric Assay in patients with metabolic bone disease
    The Journal of Clinical Endocrinology and Metabolism, 1993
    Co-Authors: Patrick Garnero, Pierre D Delmas
    Abstract:

    We measured serum bone alkaline phosphatase (B-ALP) with a new Immunoradiometric Assay (IRMA) in a large sample of healthy controls comprising 173 women and 180 men, 20-88 yr of age, and in patients with metabolic bone disease. Using serum samples from patients with liver disease and patients with Paget's disease with elevated total alkaline phosphatase (T-ALP) as a source of, respectively, liver and bone isoenzymes, we determined a liver cross-reactivity of the IRMA of 16% that was confirmed by electrophoresis of the circulating alkaline phosphatase isoenzymes. The IRMA was linear for serial sample dilutions, the recovery ranged from 89-110%, and the intra- and interAssay variations were below 7% and 9%, respectively. B-ALP increased linearly with age in both sexes, and the mean B-ALP serum levels were not significantly different for women and men (11.3 +/- 4.8 ng/mL for women; 11.0 +/- 4.0 ng/mL for men). The increase in B-ALP after the menopause was significantly higher than that in T-ALP (+77% vs. +24%; P < 0.001). When the values of postmenopausal women were expressed as the SD from the mean of premenopausal women, the mean Z scores were 2.2 +/- 1.8 for B-ALP and 0.9 +/- 1.3 for T-ALP (P < 0.001 between the two). Serum B-ALP was increased from control values in patients with Paget's disease (n = 57; mean, 171.8 +/- 135.6 ng/mL; P < 0.001), in patients with primary hyperparathyroidism (n = 18; mean, 17.2 +/- 5.9 ng/mL; P < 0.001), and in patients with chronic renal failure on hemodialysis (n = 83; mean, 36.6 +/- 35.7 ng/mL; P < 0.001). In patients with Paget's disease, B-ALP was highly correlated with T-ALP (r2 = 0.94; P < 0.001), and the decrease in its serum level was larger than that in T-ALP after treatment with the bisphosphonate pamidronate (-58% vs. -43%; P < 0.03). In patients with various liver diseases, B-ALP was slightly increased, but stayed within the normal range (mean +/- 2 SD) until T-ALP did not exceed 4.5 mu katal/L. We conclude that this new IRMA for B-ALP is reliable, has a low cross-reactivity with the liver isoenzyme, and appears to be more sensitive than T-ALP for the clinical investigation of patients with osteoporosis and other metabolic bone diseases.

F B Michel - One of the best experts on this subject based on the ideXlab platform.

  • serum fragment of cytokeratin subunit 19 measured by cyfra 21 1 Immunoradiometric Assay as a marker of lung cancer
    Cancer Research, 1993
    Co-Authors: Jeanlouis Pujol, Jean Grenier, Jeanpierre Daures, Alain Daver, Henri Pujol, F B Michel
    Abstract:

    Cytokeratin 19 is a subunit of cytokeratin intermediate filament expressed in simple epithelia and their malignant counterparts. Therefore, it is expressed by respiratory epithelium cells and has been detected in lung cancer specimens. An Immunoradiometric Assay was used to detect a fragment of the cytokeratin 19, referred to as CYFRA 21-1, in the serum of 165 patients with histologically proved lung cancer (128 non-small cell and 37 small cell lung cancers). This prospective study was conducted to evaluate the reliability of this Immunoradiometric Assay and to identify the relationship between serum CYFRA 21-1 and different features of lung cancer including prognosis. The minimal detectable concentration detected by this Assay was 0.06 ng/ml. The reliability of the Immunoradiometric Assay was demonstrated by the linear relationship between CYFRA 21-1 measurement and dilution of the serum, the reproducibility of the dosage in intraAssay and interAssay, and the high sensitivity of the method in discriminating low CYFRA 21-1 concentrations. Using a threshold of 3.6 ng/ml, sensitivity and specificity were 0.52 and 0.87, respectively. The sensitivity of the marker was highest in squamous cell carcinoma and lowest in small cell carcinoma. In non-small cell lung cancer patients, the marker varied significantly according to both stage of the disease (Kruskal-Wallis, 13.7; P < 0.005) and performance status (Kruskal-Wallis, 9.16; P < 0.05) inasmuch as a high serum CYFRA 21-1 level was associated with advanced stages, mediastinal lymph nodes, and poor performance status. Consequently, the marker was significantly lower in patients who were operated upon when compared with unresectable ones. Lung cancer patients with serum CYFRA 21-1 over 3.6 ng/ml proved to have a significantly shorter overall survival than those with a normal serum level (log rank, P = 0.007; Wilcoxon, P = 0.001). The negative prognostic effect of CYFRA 21-1 was highly significant in squamous cell carcinomas whereas it was nonsignificant for the other histologies. In Cox's model analysis, performance status, stage grouping, and CYFRA 21-1 were the only significant determinants of survival. This study supports the use of the serum fragment of cytokeratin subunit 19 CYFRA 21-1 as an independent prognostic marker of squamous cell carcinoma of the lung.

Thomas H Tarter - One of the best experts on this subject based on the ideXlab platform.

  • serum heterophile antibodies interfere with prostate specific antigen test and result in over treatment in a patient with prostate cancer
    The Journal of Urology, 2001
    Co-Authors: Bradley R Morgan, Thomas H Tarter
    Abstract:

    Purpose: We evaluated how naturally occurring heterophile antibodies in patient serum interfered with prostate specific antigen (PSA) immunoAssay, resulting in over treatment for prostate cancer.Materials and Methods: Serum samples were treated with heterophilic blocking reagent (Scantibodies Laboratory, Inc., Santee, California). Treated and untreated samples were tested by the Medics (Tosoh, Foster City, California) Tandem-R (Beckman-Coulter Inc., Chaska, Minnesota) and Elecsys (Roche Molecular Biochemical, Indianapolis, Indiana) PSA Assays. Heterophile antibodies were measured directly in treated and untreated samples by the human anti-mouse antibody Immunoradiometric Assay and heterophilic antibody identification enzyme immunoAssay (Scantibodies Laboratories, Inc.).Results: Human anti-mouse Ig heterophile antibodies in patient serum caused false-positive PSA test findings after radical prostatectomy, resulting in over treatment for presumed disease recurrence.Conclusions: If PSA is detectable after ra...

Byeongcheol Ahn - One of the best experts on this subject based on the ideXlab platform.

  • effects of anti thyroglobulin antibody on the measurement of thyroglobulin differences between Immunoradiometric Assay kits available
    The Korean Journal of Nuclear Medicine, 2005
    Co-Authors: Byeongcheol Ahn, Jinho Bae, Shin Young Jeong, Ho Yong Park, Jung Guk Kim, Jihyeong Seo, Jeongsoo Yoo, Jinhyang Jung, Jinho Sohn, In Kyu Lee
    Abstract:

    Purpose: Thyroglobulin (Tg) is a valuable and sensitive tool as a marker for diagnosis and follow-up for several thyroid disorders, especially, in the follow-up of patients with differentiated thyroid cancer (DTC). Often, clinical decisions rely entirely on the serum Tg concentration. But the Tg Assay is one of the most challenging laboratory measurements to perform accurately owing to antithyroglobulin antibody (Anti-Tg). In this study, we have compared the degree of Anti-Tg effects on the measurement of Tg between availale Tg measuring kits. Materials and Methods: Measurement of Tg levels for standard Tg solution was performed with two different kits commercially available (A/B kits) using Immunoradiometric Assay technique either with absence or presence of three different concentrations of Anti-Tg. Measurement of Tg for patient's serum was also performed with the same kits. Patient's serum samples were prepared with mixtures of a serum containing high Tg levels and a serum containg high Anti-Tg concentrations. Results: In the measurements of standard Tg solution, presence of Anti-Tg resulted in falsely lower Tg level by both A and B kits. Degree of Tg underestimation by h kit was more prominent than B kit. The degree of underestimation by B kit was trivial therefore clinically insignificant, but statistically significant. Addition of Anti-Tg to patient serum resulted in falsely lower Tg levels with only A kit. Conclusion: Tg level could be underestimated in the presence of anti-Tg. Anti-Tg effect on Tg measurement was variable according to Assay kit used. Therefore, accuracy test must be performed for individual Tg-Assay kit.

  • influence of anti thyroglobulin antibody on the measurement of thyroglobulin using the Immunoradiometric Assay
    Endocrinology and Metabolism, 2004
    Co-Authors: Byeongcheol Ahn, Jinho Bae, Shin Young Jeong, Ho Yong Park, Jung Guk Kim, Jaetae Lee, Bo Wan Kim, Kyu Bo Lee
    Abstract:

    Background: Serum thyroglobulin (Tg) is a valuable and sensitive tool needed in the follow-up of patients with differentiated thyroid cancer (DTC), but antithyroglobulin antibody (Anti-Tg), common in patients with DTC, can interfere with the Assay for Tg. In this study, we evaluated the influence of Anti-Tg on the measurement of Tg using the Immunoradiometric Assay (IRMA). Methods: In using ELSA-hTg in vivo test (CIS international, Schering, France), a solid phase two-site IRMA was used to measure Tg (23.5 ng/mL, 62.5 ng/mL) under the absence or presence of three concentrations of Anti-Tg (25U/mL, 50U/mL, 100U/mL). We also performed Tg measurement using patients serum that was mixed with patients serum containing high Anti-Tg. ANOVA and Scheffe tests were performed to evaluate the effect of Anti-Tg on Tg IRMA, and an inverse regression was made to calculate the level of Tg from measured Tg and used Anti-Tg levels and also to assess the degree of effect of anti-Tg on Tg IRMA. Results: In measuring Tg using the standard solution, the presence of Anti-Tg resulted in a falsely suppressed Tg value. The IRMAs for 23.5ng/mL of the standard Tg solution resulted in 24.51.1 ng/mL under no Anti-Tg, 11.8M0.4 ng/mL under 25U/mL of Anti-Tg, 7.70.1 ng/mL under 50U/mL of Anti-Tg, and 4.50.4 ng/mL under 100U/mL of Anti-Tg. IRMAs 62.5 ng/mL of the standard Tg solution resulted in 65.95.7 ng/mL under no Anti-Tg, 36.32.2 ng/mL under 25U/mL of Anti-Tg, 23.70.7 ng/mL under 50U/mL of Anti-Tg, and 14.01.0 ng/mL under 100U/mL of Anti-Tg. (ANOVA test, p=0.000). The degree of suppression of the measured Tg value was positively correlated with the Anti-Tg level (Quadratic model regression, Sig T=0.000). The presence of Anti-Tg also resulted in a falsely suppressed Tg value for the Tg measurement using patient's serum. Conclusion: The presence of Anti-Tg could consist of the use of Tg as a tumor, therefore Anti-Tg should be measured in all patients diagnosed with DTC. The interpretation of the Tg level must be performed with extreme caution in patients with Anti-Tg.