6 results on '"Pope, Adele J."'
Number of results to display per page
Search Results
2. The accuracy of coronary CT angiography in patients with coronary calcium score above 1000 Agatston Units:Comparison with quantitative coronary angiography: Coronary CT Angiography in High Coronary Calcium
- Author
-
Kwan, Alan C., Gransar, Heidi, Tzolos, Evangelos, Chen, Billy, Otaki, Yuka, Klein, Eyal, Pope, Adele J., Han, Donghee, Howarth, Andrew, Jain, Nishita, Dey, Damini, Miller, Robert JH, Cheng, Victor, Azarbal, Babak, and Berman, Daniel S.
- Subjects
Stenosis ,Quantitative coronary angiography ,Coronary CT angiography ,Coronary artery calcium ,Coronary calcium score ,Accuracy - Abstract
Background: High amounts of coronary artery calcium (CAC) pose challenges in interpretation of coronary CT angiography (CCTA). The accuracy of stenosis assessment by CCTA in patients with very extensive CAC is uncertain. Methods: Retrospective study was performed including patients who underwent clinically directed CCTA with CAC score >1000 and invasive coronary angiography within 90 days. Segmental stenosis on CCTA was graded by visual inspection with two-observer consensus using categories of 0%, 1–24%, 25–49%, 50–69%, 70–99%, 100% stenosis, or uninterpretable. Blinded quantitative coronary angiography (QCA) was performed on all segments with stenosis ≥25% by CCTA. The primary outcome was vessel-based agreement between CCTA and QCA, using significant stenosis defined by diameter stenosis ≥70%. Secondary analyses on a per-patient basis and inclusive of uninterpretable segments were performed. Results: 726 segments with stenosis ≥25% in 346 vessels within 119 patients were analyzed. Median coronary calcium score was 1616 (1221–2118). CCTA identification of QCA-based stenosis resulted in a per-vessel sensitivity of 79%, specificity of 75%, positive predictive value (PPV) of 45%, negative predictive value (NPV) of 93%, and accuracy 76% (68 false positive and 15 false negative). Per-patient analysis had sensitivity 94%, specificity 55%, PPV 63%, NPV 92%, and accuracy 72% (30 false-positive and 3 false-negative). Inclusion of uninterpretable segments had variable effect on sensitivity and specificity, depending on whether they are considered as significant or non-significant stenosis. Conclusions: In patients with very extensive CAC (>1000 Agatston units), CCTA retained a negative predictive value > 90% to identify lack of significant stenosis on a per-vessel and per-patient level, but frequently overestimated stenosis.
- Published
- 2021
3. Three-dimensional transmural organization of perimysial collagen in the heart
- Author
-
Pope, Adele J., Sands, Gregory B., Smaill, Bruce H., and LeGrice, Ian J.
- Subjects
Connective tissues -- Properties ,Heart muscle -- Properties ,Collagen -- Properties ,Confocal microscopy -- Methods ,Physiological research ,Biological sciences - Abstract
There is strong support for the view that the ventricular myocardium has a laminar organization in which myocytes are grouped into branching layers separated by cleavage planes. However, understanding of the extent and functional implications of this architecture has been limited by the lack of a systematic three-dimensional description of the organization of myocytes and associated perimysial collagen. We imaged myocytes and collagen across the left ventricular wall at high resolution in seven normal rat hearts using extended volume confocal microscopy. We developed novel reconstruction and segmentation techniques necessary for the quantitative analysis of three-dimensional myocyte and perimysial collagen organization. The results confirm that perimysial collagen has an ordered arrangement and that it defines a laminar organization. Perimysial collagen is composed of three distinct forms: extensive meshwork on laminar surfaces, convoluted fibers connecting adjacent layers, and longitudinal cords. While myolaminae are the principal form of structural organization throughout most of the wall, they are not seen in the subepicardium, where perimysial collagen is present only as longitudinal cords. connective tissue; perimysium; myocardium; laminar architecture
- Published
- 2008
4. Pressure overload-induced hypertrophy in transgenic mice selectively overexpressing [AT.sub.2] receptors in ventricular myocytes
- Author
-
Yan, Xinhua, Schuldt, Adam J.T., Price, Robert L., Amende, Ivo, Liu, Fen-Fen, Okoshi, Katashi, Ho, Kalon K.L., Pope, Adele J., Borg, Thomas K., Lorell, Beverly H., and Morgan, James P.
- Subjects
Heart enlargement -- Physiological aspects ,Heart enlargement -- Causes of ,Heart cells -- Health aspects ,Heart cells -- Properties ,Angiotensin -- Receptors ,Angiotensin -- Health aspects ,Angiotensin -- Properties ,Biological sciences - Abstract
The role of the angiotensin II type 2 ([AT.sub.2]) receptor in cardiac hypertrophy remains controversial. We studied the effects of [AT.sub.2] receptors on chronic pressure overload-induced cardiac hypertrophy in transgenic mice selectively overexpressing A[T.sub.2] receptors in ventricular myocytes. Left ventricular (LV) hypertrophy was induced by ascending aorta banding (AS). Transgenic mice overexpressing [AT.sub.2] ([AT.sub.2]TG-AS) and nontransgenic mice (NTG-AS) were studied after 70 days of aortic banding. Nonbanded NTG mice were used as controls. LV function was determined by catheterization via LV puncture and cardiac magnetic resonance imaging. LV myocyte diameter and interstitial collagen were determined by confocal microscopy. Atrial natriuretic polypeptide (ANP) and brain natriuretic peptide (BNP) were analyzed by Northern blot. Sarco(endo)plasmic reticulum [Ca.sup.2+]-ATPase (SERCA)2, inducible nitric oxide synthase (iNOS), endothelial NOS, ERK1/2, p70S6K, Src-homology 2 domain-containing protein tyrosine phosphatase-1, and protein serine/threonine phosphatase 2A were analyzed by Western blot. LV myocyte diameter and collagen were significantly reduced in [AT.sub.2]TG-AS compared with NTG-AS mice. LV anterior and posterior wall thickness were not different between [AT.sub.2]TG-AS and NTG-AS mice. LV systolic and diastolic dimensions were significantly higher in [AT.sub.2]TG-AS than in NTG-AS mice. LV systolic pressure and end-diastolic pressure were lower in [AT.sub.2]TG-AS than in NTG-AS mice. ANP, BNP, and SERCA2 were not different between [AT.sub.2]TG-AS and NTG-AS mice. Phospholamban (PLB) and the PLB-to-SERCA2 ratio were significantly higher in [AT.sub.2]TG-AS than in NTG-AS mice. iNOS was higher in [AT.sub.2]TG-AS than in NTG-AS mice but not significantly different. Our results indicate that [AT.sub.2] receptor overexpression modified the pathological hypertrophic response to aortic banding in transgenic mice. cardiomyocyte; angiotensin II type 2 receptor; gene expression; protein expression
- Published
- 2008
5. Regeneration of the heart in diabetes by selective copper chelation
- Author
-
Cooper, Garth J.S., Phillips, Anthony R.J., Choong, Soon Y., Leonard, Bridget L., Crossman, David J., Brunton, Dianne H., Saafi, 'Etuate L., Dissanayake, Ajith M., Cowan, Brett R., Young, Alistair A., Occleshaw, Christopher J., Chan, Yih-Kai, Leahy, Fiona E., Keogh, Geraldine F., Gamble, Gregory D., Allen, Grant R., Pope, Adele J., Boyd, Peter D.W., Poppitt, Sally D., Borg, Thomas K., Doughty, Robert N., and Baker, John R.
- Subjects
University of Auckland -- Services ,Diabetes -- Diagnosis -- Care and treatment ,Heart -- Care and treatment ,Health ,Diagnosis ,Care and treatment ,Services - Abstract
Heart disease is the major cause of death in diabetes, a disorder characterized by chronic hyperglycemia and cardiovascular complications. Although altered systemic regulation of transition metals in diabetes has been the subject of previous investigation, it is not known whether changed transition metal metabolism results in heart disease in common forms of diabetes and whether metal chelation can reverse the condition. We found that administration of the Cu-selective transition metal chelator trientine to rats with streptozotocin-induced diabetes caused increased urinary Cu excretion compared with matched controls. A [Cu.sup.II]-trientine complex was demonstrated in the urine of treated rats. In diabetic animals with established heart failure, we show here for the first time that 7 weeks of oral trientine therapy significantly alleviated heart failure without lowering blood glucose, substantially improved cardiomyocyte structure, and reversed elevations in left ventricular collagen and [β.sub.1] integrin. Oral trientine treatment also caused elevated Cu excretion in humans with type 2 diabetes, in whom 6 months of treatment caused elevated left ventricular mass to decline significantly toward normal. These data implicate accumulation of elevated loosely bound Cu in the mechanism of scardiac damage in diabetes and support the use of selective Cu chelation in the treatment of this condition., Diabetes accompanied by increased prevalence of left ventricular (LV) hypertrophy (LVH), LV dysfunction, and coronary artery disease (1), but the mechanism by which hyperglycemia or associated metabolic abnormalities lead to [...]
- Published
- 2004
6. Pressure overload-induced hypertrophy in transgenic mice selectively overexpressing AT2 receptors in ventricular myocytes.
- Author
-
Xinhua Yan, Schuldt, Adam J. T., Price, Robert L., Amende, Ivo, Fen-Fen Liu, Okoshi, Katashi, Ho, Kalon K. L., Pope, Adele J., Borg, Thomas K., Lorell, Beverly H., and Morgan, James P.
- Subjects
ANGIOTENSINS ,TRANSGENIC mice ,MUSCLE cells ,CARDIAC hypertrophy ,MAGNETIC resonance imaging - Abstract
The role of the angiotensin II type 2 (AT
2 ) receptor in cardiac hypertrophy remains controversial. We studied the effects of AT2 receptors on chronic pressure overload-induced cardiac hypertrophy in transgenic mice selectively overexpressing AT2 receptors in ventricular myocytes. Left ventricular (LV) hypertrophy was induced by ascending aorta banding (AS). Transgenic mice overexpressing AT2 (AT2 TG-AS) and nontransgenic mice (NTG-AS) were studied after 70 days of aortic banding. Nonbanded NTG mice were used as controls. LV function was determined by catheterization via LV puncture and cardiac magnetic resonance imaging. LV myocyte diameter and interstitial collagen were deter- mined by confocal microscopy. Atrial natriuretic polypeptide (ANP) and brain natriuretic peptide (BNP) were analyzed by Northern blot. Sarco(endo)plasmic reticulum Ca2+ -ATPase (SERCA)2, inducible nitric oxide synthase (iNOS), endothelial NOS, ERK1/2, p7056K, Src-homology 2 domain-containing protein tyrosine phosphatase-1, and protein serine/threonine phosphatase 2A were analyzed by Western blot. LV myocyte diameter and collagen were significantly' reduced in AT2 TG-AS compared with NTG-AS mice. LV anterior and posterior wall thickness were not different between AT2 TG-AS and NTG-AS mice. LV systolic and diastolic dimensions were significantly higher in AT2 TG-AS than in NTG-AS mice. LV systolic pressure and end-diastolic pressure were lower in AT2 TG-AS than in NTG-AS mice. ANP, BNP, and SERCA2 were not different between AT2 TG-AS and NTG-AS mice. Phospholamban (PLB) and the PLB- to-SERCA2 ratio were significantly higher in AT2 TG-AS than in NTG-AS mice. iNOS was higher in AT2 TG-AS than in NTG-AS mice but not significantly different. Our results indicate that AT2 receptor overexpression modified the pathological hypertrophic response to aortic banding in transgenic mice. [ABSTRACT FROM AUTHOR]- Published
- 2008
- Full Text
- View/download PDF
Catalog
Books, media, physical & digital resources
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.