The Experts below are selected from a list of 84 Experts worldwide ranked by ideXlab platform
David L. Vesely - One of the best experts on this subject based on the ideXlab platform.
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Atrial natriuretic hormones originating from the N-terminus of the atrial natriuretic factor prohormone.
Clinical and experimental pharmacology & physiology, 1995Co-Authors: David L. VeselyAbstract:SUMMARY 1. Four peptide hormones consisting of amino acids 1–30 (Long Acting Sodium Stimulator), 31–67 (Vessel Dilator), 79–98 (Kaliuretic Stimulator) and 99–126 (Atrial Natriuretic Factor [ANF]) originate from the same 126 amino acid ANF prohormone. 2. Each of these four peptide hormones circulates as a distinct peptide with vessel dilator and long acting sodium stimulator circulating at 10- to 24-fold higher concentrations than ANF while kaliuretic stimulator circulates at a three-fold higher concentration than ANF. 3. Each of these peptide hormones is released with an increase in central volume causing stretch of the atrium of the heart and with rapid heart beats greater than 125 beats/min. 4. Each of these peptide hormones lowers blood pressure, causes a diuresis and enhances sodium and/or potassium excretion. 5. In disease states which retain sodium and water such as congestive heart failure (CHF), each of these atrial peptides increases in the circulation proportionately to the severity of sodium retention, but of the Radioimmunoassays to each of these hormones only the vessel dilator Radioimmunoassay differentiates between mild (class I) CHF and healthy individuals.
Mark A Richards - One of the best experts on this subject based on the ideXlab platform.
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brain natriuretic peptide and n terminal brain natriuretic peptide in the diagnosis of heart failure in patients with acute shortness of breath
Journal of the American College of Cardiology, 2003Co-Authors: John G. Lainchbury, Elizabeth J Campbell, Gary M Nicholls, Chris Frampton, Timothy G. Yandle, Mark A RichardsAbstract:Abstract Objectives This study sought to compare the utility of measurement of plasma brain natriuretic peptide (BNP) and N-terminal brain natriuretic peptide (N-BNP) in the diagnosis of heart failure (HF) in patients with acute dyspnea. Background Plasma BNP is useful in differentiating HF from other causes of dyspnea in the emergency department. The N-terminal component of BNP has a longer half-life, and in HF increases in plasma N-BNP are proportionately greater. Methods We studied 205 patients (average age 70 ± 14 years) presenting to the emergency department with acute dyspnea. Brain natriuretic peptide was analyzed using a point-of-care test and two locally developed Radioimmunoassays. N-terminal BNP was measured using a locally developed Radioimmunoassay and a commercially available assay. Final diagnosis of HF was adjudicated by two cardiologists. Results Patients with HF (n = 70) had higher mean levels of both hormones by all assays (p Conclusions Measurement of BNP or N-BNP is useful in the diagnosis of HF in acute dyspnea. Commercially available assays compare favorably with well-validated laboratory assays. Differences in sensitivity and specificity may influence the assay choice in this setting.
Susan F Greenhut - One of the best experts on this subject based on the ideXlab platform.
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measurement of steroid sex hormones in serum a comparison of Radioimmunoassay and mass spectrometry
Steroids, 2002Co-Authors: Joanne F Dorgan, Thomas R Fears, Robert P Mcmahon, Lisa Aronson Friedman, Blossom H Patterson, Susan F GreenhutAbstract:Concern has been raised about the adequacy of Radioimmunoassays to measure steroid sex hormones in population studies. We compared steroid sex hormone measurements in serum by Radioimmunoassay with mass spectrometry. Four male and four female serum pools with known relative concentrations of steroid sex hormones were measured multiple times by both methods. Because measurements are expected to increase linearly with concentration for each sex, we examined whether the linear regressions of hormone measurements on concentration were the same for Radioimmunoassay and mass spectrometry. Estradiol, estrone, androstenedione, testosterone, and dehydroepiandrosterone sulfate were measured in female pools; testosterone, dihydrotestosterone, androstenedione, and dehydroepiandrosterone sulfate were measured in male pools. Regression slopes for Radioimmunoassay and mass spectrometry measurements were comparable for all hormones except androstenedione, which had a steeper slope when measured by mass spectrometry (P ≤ 0.02). Intercepts for Radioimmunoassay and mass spectrometry were similar and close to zero for estradiol, androstenedione, dehydroepiandrosterone sulfate, and in male samples, testosterone. For testosterone in female samples, estrone, and dihydrotestosterone, Radioimmunoassay and mass spectrometry intercepts differed significantly. Standard deviations of individual measurements by Radioimmunoassay and mass spectrometry differed by hormone and serum concentration; neither method consistently measured hormone concentrations with less variability. Our findings suggest that although absolute concentrations may differ for some hormones, Radioimmunoassay and mass spectrometry can yield similar estimates of between subject differences in serum concentrations of most steroid sex hormones commonly measured in population studies. Relative power of studies using Radioimmunoassay and mass spectrometry will depend on the hormones measured and their serum concentrations.
John G. Lainchbury - One of the best experts on this subject based on the ideXlab platform.
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brain natriuretic peptide and n terminal brain natriuretic peptide in the diagnosis of heart failure in patients with acute shortness of breath
Journal of the American College of Cardiology, 2003Co-Authors: John G. Lainchbury, Elizabeth J Campbell, Gary M Nicholls, Chris Frampton, Timothy G. Yandle, Mark A RichardsAbstract:Abstract Objectives This study sought to compare the utility of measurement of plasma brain natriuretic peptide (BNP) and N-terminal brain natriuretic peptide (N-BNP) in the diagnosis of heart failure (HF) in patients with acute dyspnea. Background Plasma BNP is useful in differentiating HF from other causes of dyspnea in the emergency department. The N-terminal component of BNP has a longer half-life, and in HF increases in plasma N-BNP are proportionately greater. Methods We studied 205 patients (average age 70 ± 14 years) presenting to the emergency department with acute dyspnea. Brain natriuretic peptide was analyzed using a point-of-care test and two locally developed Radioimmunoassays. N-terminal BNP was measured using a locally developed Radioimmunoassay and a commercially available assay. Final diagnosis of HF was adjudicated by two cardiologists. Results Patients with HF (n = 70) had higher mean levels of both hormones by all assays (p Conclusions Measurement of BNP or N-BNP is useful in the diagnosis of HF in acute dyspnea. Commercially available assays compare favorably with well-validated laboratory assays. Differences in sensitivity and specificity may influence the assay choice in this setting.
Gary M Nicholls - One of the best experts on this subject based on the ideXlab platform.
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brain natriuretic peptide and n terminal brain natriuretic peptide in the diagnosis of heart failure in patients with acute shortness of breath
Journal of the American College of Cardiology, 2003Co-Authors: John G. Lainchbury, Elizabeth J Campbell, Gary M Nicholls, Chris Frampton, Timothy G. Yandle, Mark A RichardsAbstract:Abstract Objectives This study sought to compare the utility of measurement of plasma brain natriuretic peptide (BNP) and N-terminal brain natriuretic peptide (N-BNP) in the diagnosis of heart failure (HF) in patients with acute dyspnea. Background Plasma BNP is useful in differentiating HF from other causes of dyspnea in the emergency department. The N-terminal component of BNP has a longer half-life, and in HF increases in plasma N-BNP are proportionately greater. Methods We studied 205 patients (average age 70 ± 14 years) presenting to the emergency department with acute dyspnea. Brain natriuretic peptide was analyzed using a point-of-care test and two locally developed Radioimmunoassays. N-terminal BNP was measured using a locally developed Radioimmunoassay and a commercially available assay. Final diagnosis of HF was adjudicated by two cardiologists. Results Patients with HF (n = 70) had higher mean levels of both hormones by all assays (p Conclusions Measurement of BNP or N-BNP is useful in the diagnosis of HF in acute dyspnea. Commercially available assays compare favorably with well-validated laboratory assays. Differences in sensitivity and specificity may influence the assay choice in this setting.
