The Experts below are selected from a list of 42 Experts worldwide ranked by ideXlab platform
Shaw Callen - One of the best experts on this subject based on the ideXlab platform.
-
Pilot quality assurance programme for plasma metanephrines.
Annals of clinical biochemistry, 2010Co-Authors: Dilo Pillai, Shaw CallenAbstract:Up to 2007 there was no formal external quality assurance programme for plasma free metanephrines. A pilot programme was conceived by the AACB (Australian Association of Clinical Biochemists) Working Party on biogenic amines. With support from the AACB and Royal College of Pathologists of Australasia Quality Assurance programmes, a pilot study was developed. Data from this study are presented for the first time. Twelve lyophilized plasma samples were distributed to 15 centres. Samples were spiked with metanephrine (Metadrenaline), normetanephrine (norMetadrenaline) and 3-methoxytyramine, all derived from human urine. Concentrations were arranged in a linear relationship. The analytes were present at six levels and samples were duplicated. High-pressure liquid chromatography and tandem mass spectrometry methods showed acceptable precision but in general enzyme immunoassay displayed a higher degree of imprecision as well as a negative bias. Differences in calibration and matrix effects are likely to have been responsible for the discrepancy between chromatographic and immunoassay methods. These differences need to be further examined although efforts at standardization between different methods have been hampered by the lack of a universal calibrator for plasma metanephrines. Meanwhile, a laboratory's performance characteristics can be monitored and enhanced by participation in suitable external quality assurance programmes.
-
Pilot quality assurance programme for plasma metanephrines
Annals of Clinical Biochemistry, 2010Co-Authors: Dilo Pillai, Shaw CallenAbstract:BackgroundUp to 2007 there was no formal external quality assurance programme for plasma free metanephrines. A pilot programme was conceived by the AACB (Australian Association of Clinical Biochemists) Working Party on biogenic amines. With support from the AACB and Royal College of Pathologists of Australasia Quality Assurance programmes, a pilot study was developed. Data from this study are presented for the first time.MethodsTwelve lyophilized plasma samples were distributed to 15 centres. Samples were spiked with metanephrine (Metadrenaline), normetanephrine (norMetadrenaline) and 3-methoxytyramine, all derived from human urine. Concentrations were arranged in a linear relationship. The analytes were present at six levels and samples were duplicated.ResultsHigh-pressure liquid chromatography and tandem mass spectrometry methods showed acceptable precision but in general enzyme immunoassay displayed a higher degree of imprecision as well as a negative bias.ConclusionsDifferences in calibration and matr...
Ross Mcd Young - One of the best experts on this subject based on the ideXlab platform.
-
Mechanisms of change in negative thinking and urinary monoamines in depressed patients during acute treatment with group cognitive behavior therapy and antidepressant medication
2010Co-Authors: Genevieve A Dingle, Tian Po S Oei, Ross Mcd YoungAbstract:This naturalistic study investigated the mechanisms of change in measures of negative thinking and in 24-h urinary metabolites of noradrenaline (norepinephrine), dopamine and serotonin in a sample of 43 depressed hospital patients attending an eight-session group cognitive behavior therapy program. Most participants (91%) were taking antidepressant medication throughout the therapy period according to their treating Psychiatrists' prescriptions. The sample was divided into outcome categories (19 Responders and 24 Non-responders) on the basis of a clinically reliable change index [Jacobson, N.S., & Truax, P., 1991. Clinical significance: a statistical approach to defining meaningful change in psychotherapy research. Journal of Consulting and Clinical Psychology, 59, 12–19.] applied to the Beck Depression Inventory scores at the end of the therapy. Results of repeated measures analysis of variance [ANOVA] analyses of variance indicated that all measures of negative thinking improved significantly during therapy, and significantly more so in the Responders as expected. The treatment had a significant impact on urinary adrenaline and Metadrenaline excretion however, these changes occurred in both Responders and Non-responders. Acute treatment did not significantly influence the six other monoamine metabolites. In summary, changes in urinary monoamine levels during combined treatment for depression were not associated with self-reported changes in mood symptoms.
-
Mechanisms of change in negative thinking and urinary monoamines in depressed patients during acute treatment with group cognitive behavior therapy and antidepressant medication.
Psychiatry Research, 2010Co-Authors: Genevieve A Dingle, Tian Po S Oei, Ross Mcd YoungAbstract:This naturalistic study investigated the mechanisms of change in measures of negative thinking and in 24-h urinary metabolites of noradrenaline (norepinephrine), dopamine and serotonin in a sample of 43 depressed hospital patients attending an eight-session group cognitive behavior therapy program. Most participants (91%) were taking antidepressant medication throughout the therapy period according to their treating Psychiatrists' prescriptions. The sample was divided into outcome categories (19 Responders and 24 Non-responders) on the basis of a clinically reliable change index [Jacobson, N.S., & Truax, P., 1991. a statistical approach to defining meaningful change in psychotherapy research. Journal of Consulting and Clinical Psychology, 59, 12-19.] applied to the Beck Depression Inventory scores at the end of the therapy. Results of repeated measures analysis of variance [ANOVA] analyses of variance indicated that all measures of negative thinking improved significantly during therapy, and significantly more so in the Responders as expected. The treatment had a significant impact on urinary adrenaline and Metadrenaline excretion however, these changes occurred in both Responders and Non-responders. Acute treatment did not significantly influence the six other monoamine metabolites. In summary, changes in urinary monoamine levels during combined treatment for depression were not associated with self-reported changes in mood symptoms.
Dilo Pillai - One of the best experts on this subject based on the ideXlab platform.
-
Pilot quality assurance programme for plasma metanephrines.
Annals of clinical biochemistry, 2010Co-Authors: Dilo Pillai, Shaw CallenAbstract:Up to 2007 there was no formal external quality assurance programme for plasma free metanephrines. A pilot programme was conceived by the AACB (Australian Association of Clinical Biochemists) Working Party on biogenic amines. With support from the AACB and Royal College of Pathologists of Australasia Quality Assurance programmes, a pilot study was developed. Data from this study are presented for the first time. Twelve lyophilized plasma samples were distributed to 15 centres. Samples were spiked with metanephrine (Metadrenaline), normetanephrine (norMetadrenaline) and 3-methoxytyramine, all derived from human urine. Concentrations were arranged in a linear relationship. The analytes were present at six levels and samples were duplicated. High-pressure liquid chromatography and tandem mass spectrometry methods showed acceptable precision but in general enzyme immunoassay displayed a higher degree of imprecision as well as a negative bias. Differences in calibration and matrix effects are likely to have been responsible for the discrepancy between chromatographic and immunoassay methods. These differences need to be further examined although efforts at standardization between different methods have been hampered by the lack of a universal calibrator for plasma metanephrines. Meanwhile, a laboratory's performance characteristics can be monitored and enhanced by participation in suitable external quality assurance programmes.
-
Pilot quality assurance programme for plasma metanephrines
Annals of Clinical Biochemistry, 2010Co-Authors: Dilo Pillai, Shaw CallenAbstract:BackgroundUp to 2007 there was no formal external quality assurance programme for plasma free metanephrines. A pilot programme was conceived by the AACB (Australian Association of Clinical Biochemists) Working Party on biogenic amines. With support from the AACB and Royal College of Pathologists of Australasia Quality Assurance programmes, a pilot study was developed. Data from this study are presented for the first time.MethodsTwelve lyophilized plasma samples were distributed to 15 centres. Samples were spiked with metanephrine (Metadrenaline), normetanephrine (norMetadrenaline) and 3-methoxytyramine, all derived from human urine. Concentrations were arranged in a linear relationship. The analytes were present at six levels and samples were duplicated.ResultsHigh-pressure liquid chromatography and tandem mass spectrometry methods showed acceptable precision but in general enzyme immunoassay displayed a higher degree of imprecision as well as a negative bias.ConclusionsDifferences in calibration and matr...
Genevieve A Dingle - One of the best experts on this subject based on the ideXlab platform.
-
Mechanisms of change in negative thinking and urinary monoamines in depressed patients during acute treatment with group cognitive behavior therapy and antidepressant medication
2010Co-Authors: Genevieve A Dingle, Tian Po S Oei, Ross Mcd YoungAbstract:This naturalistic study investigated the mechanisms of change in measures of negative thinking and in 24-h urinary metabolites of noradrenaline (norepinephrine), dopamine and serotonin in a sample of 43 depressed hospital patients attending an eight-session group cognitive behavior therapy program. Most participants (91%) were taking antidepressant medication throughout the therapy period according to their treating Psychiatrists' prescriptions. The sample was divided into outcome categories (19 Responders and 24 Non-responders) on the basis of a clinically reliable change index [Jacobson, N.S., & Truax, P., 1991. Clinical significance: a statistical approach to defining meaningful change in psychotherapy research. Journal of Consulting and Clinical Psychology, 59, 12–19.] applied to the Beck Depression Inventory scores at the end of the therapy. Results of repeated measures analysis of variance [ANOVA] analyses of variance indicated that all measures of negative thinking improved significantly during therapy, and significantly more so in the Responders as expected. The treatment had a significant impact on urinary adrenaline and Metadrenaline excretion however, these changes occurred in both Responders and Non-responders. Acute treatment did not significantly influence the six other monoamine metabolites. In summary, changes in urinary monoamine levels during combined treatment for depression were not associated with self-reported changes in mood symptoms.
-
Mechanisms of change in negative thinking and urinary monoamines in depressed patients during acute treatment with group cognitive behavior therapy and antidepressant medication.
Psychiatry Research, 2010Co-Authors: Genevieve A Dingle, Tian Po S Oei, Ross Mcd YoungAbstract:This naturalistic study investigated the mechanisms of change in measures of negative thinking and in 24-h urinary metabolites of noradrenaline (norepinephrine), dopamine and serotonin in a sample of 43 depressed hospital patients attending an eight-session group cognitive behavior therapy program. Most participants (91%) were taking antidepressant medication throughout the therapy period according to their treating Psychiatrists' prescriptions. The sample was divided into outcome categories (19 Responders and 24 Non-responders) on the basis of a clinically reliable change index [Jacobson, N.S., & Truax, P., 1991. a statistical approach to defining meaningful change in psychotherapy research. Journal of Consulting and Clinical Psychology, 59, 12-19.] applied to the Beck Depression Inventory scores at the end of the therapy. Results of repeated measures analysis of variance [ANOVA] analyses of variance indicated that all measures of negative thinking improved significantly during therapy, and significantly more so in the Responders as expected. The treatment had a significant impact on urinary adrenaline and Metadrenaline excretion however, these changes occurred in both Responders and Non-responders. Acute treatment did not significantly influence the six other monoamine metabolites. In summary, changes in urinary monoamine levels during combined treatment for depression were not associated with self-reported changes in mood symptoms.
Maite Montero-hadjadje - One of the best experts on this subject based on the ideXlab platform.
-
Normotensive Incidentally Discovered Pheochromocytomas Display Specific Biochemical, Cellular, and Molecular Characteristics
Journal of Clinical Endocrinology and Metabolism, 2013Co-Authors: Magalie Haissaguerre, Maïté Courel, Sophie Denost, Laurent Yon, Christophe Dubessy, Philippe Gosse, Vincent Appavoupoulle, Genevieve Belleannée, Marie-laure Jullié, Maite Montero-hadjadjeAbstract:Design: This was a retrospective cohort recruited from 2001 to 2011 in 2 tertiary care medical departments. Patients and Methods: Clinical, biological, and radiological investigations performed in 96 consecutive patients with sporadic unilateral pheochromocytomas were examined; 47 patients had overt pheochromocytomas responsible for hypertension. Among the patients with incidental pheochromocytomas, 28 had hypertension and 21 were normotensive (NIPs). A total of 62 tumors were examined to determine the Pheochromocytoma of the Adrenal Gland Scale Score, and 29 were studied for the expression of 16 genes involved in chromaffin cell function. Context: A number of incidentally discovered pheochromocytomas are not associated with hypertension. The characteristics of normotensive incidentally discovered pheochromocytomas (NIPs) are poory known. Objective: The purpose of this work was to assess the clinical, hormonal, histological, and molecular features of NIPs. Results: Tumor size and metaiodobenzylguanidine (MIBG) scintigraphy results were similar for hypertensive pheochromocytomas (HPs) and NIPs. Patients with NIPs displayed reduced summed levels of urinary catecholamines and metanephrines and, more specifically, reduced levels of adrenaline and Metadrenaline compared with those of patients with HPs (P < .001). Urinary metanephrines had 98% diagnostic sensitivity in patients with HPs and only 75% in patients with NIPs (P < .01). Tumor diameter positively correlated with the total amount of urinary concentrations of metanephrines in patients with HPs (P < .001) but not in patients with NIPs. NIPs displayed global decreased chromaffin gene expression (reaching significance for 5 of them) and 2 corresponding proteins (phenylethanolamine N-methyltransferase and secretogranin II) and a significant increase in the cellularity, mitotic activity, and presence of atypical mitosis (P < .05). Conclusions: NIPs differ from pheochromocytomas responsible for hypertension and display features of altered chromaffin differentiation. These tumors may be misdiagnosed with the use of the usual biological diagnostic tools.