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ABSTRACT: An assay of plasma 1,5-anhydroglucitol was evaluated. Assay CVs, effects of four plasma freeze-thaw cycles, glucose up to 80 mmol/L and triglycerides up to 20 mmol/L were acceptable. 1,5-anhydroglucitol levels were significantly lower in diabetic vs. non-diabetic subjects and correlated inversely with renal function, but not with HbA1c.
Diabetes research and clinical practice 01/2012; 95(1):e17-9. · 2.16 Impact Factor
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Andrew J Boyle,
Yerem Yeghiazarians,
Henry Shih,
Joy Hwang,
Jianqin Ye,
Rich Sievers,
Daiwei Zheng,
Jath Palasubramaniam,
Dharshan Palasubramaniam, Connie Karschimkus,
Robert Whitbourn,
Alicia Jenkins,
Andrew M Wilson
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ABSTRACT: Stem cell homing to the heart is mediated by the release of chemo-attractant cytokines. Stromal derived factor -1 alpha (SDF-1a) and monocyte chemotactic factor 1(MCP-1) are detectable in peripheral blood after myocardial infarction (MI). It remains unknown if they are produced by, and released from, the heart in order to attract stem cells to repair the damaged myocardium.
Murine hearts were studied for expression of MCP-1 and SDF-1a at day 3 and day 28 following myocardial infarction to determine whether production is increased following MI. In addition, we studied the coronary artery and coronary sinus (venous) blood from patients with normal coronary arteries, stable coronary artery disease (CAD), unstable angina and MI to determine whether these cytokines are released from the heart into the systemic circulation following MI.
Both MCP-1 and SDF-1a are constitutively produced and released by the heart. MCP-1 mRNA is upregulated following murine experimental MI, but SDF-1a is suppressed. There is less release of SDF-1a into the systemic circulation in patients with all stages of CAD including MI, mimicking the animal model. However MCP-1 release from the human heart following MI is also suppressed, which is the exact opposite of the animal model.
SDF-1a and MCP-1 release from the human heart are suppressed following MI. In the case of SDF-1a, the animal model appropriately reflects the human situation. However, for MCP-1 the animal model is the exact opposite of the human condition. Human observational studies like this one are paramount in guiding translation from experimental studies to clinical trials.
Journal of Translational Medicine 09/2011; 9:150. · 3.41 Impact Factor
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ABSTRACT: To determine if levels of coated-platelets, which are potentially pro-thrombotic, are increased in end-stage renal disease patients on haemodialysis, a condition associated with high cardiovascular disease risk.
In a cross-sectional observational study, coated-platelet levels were measured by flow cytometry in 25 end-stage renal failure haemodialysis patients and 25 controls without renal disease. Associations between coated-platelet levels and clinical and biochemical factors relevant to renal and cardiovascular disease were evaluated.
Mean +/- SD coated-platelet levels were higher in the dialysis group than in the control group (39.3+/-14.3% vs 30.9+/-10.3%, P=0.02). The number of subjects with high coated-platelet levels (>40%) was larger in the dialysis than in the control group (13/25 vs 4/25, chi(2) test, P=0.007). On univariate analysis, coated-platelet levels correlated with serum C-reactive protein levels in renal failure (r=0.47, P=0.02) and inversely with white cell count in the control group (r= -0.60, P=0.001). Coated-platelet levels were higher in dialysis patients reporting alcohol abstinence than among those reporting 'social' drinking (44.3+/-12.6 vs 28.8+/-13.5%, P=0.01). Age, gender, body weight, smoking, diabetes, lipid levels and lipid-lowering drugs were not associated with coated-platelet levels (all P>0.05).
Coated-platelet levels are increased in haemodialysis patients relative to subjects with normal renal function, and are related to inflammation and alcohol abstinence. Other vascular risk factors, such as smoking, lipids and diabetes, were not related to coated-platelet levels. Coated-platelets may be implicated in the increased thrombosis and vascular risk in end-stage renal disease.
Nephrology 12/2008; 14(2):148-54. · 1.31 Impact Factor
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Peter Hoffmann,
Jade Woon,
Kevin G Rowley, Connie Karschimkus,
Craig L Nelson,
George Dragicevic,
David O'Neal,
Andrew Wilson,
Kevin D Croft,
Trevor A Mori,
Bruce E Kemp,
James D Best,
Alicia J Jenkins
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ABSTRACT: Modified haemoglobin levels were quantified in 21 Type 1 and 21 Type 2 diabetic patients and two groups of 17 non-diabetic subjects. Glycated haemoglobin levels were increased in diabetes but glutathionyl haemoglobin (HbSSG) levels did not differ between groups, nor by complications; nor correlate with haemoglobin glycation or vascular risk factors.
Diabetes research and clinical practice 06/2008; 80(2):e1-3. · 2.16 Impact Factor
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ABSTRACT: Semicarbazide-sensitive amine oxidase (SSAO; EC 1.4.3.6) is a copper-containing enzyme predominantly expressed by vascular smooth muscle cells. SSAO deaminates primary amines to produce aldehydes and oxygen peroxides, and may thus play a role in vascular damage. SSAO activity can be quantified by assaying benzaldehyde production using fluorescent derivatisation and separation by HPLC. We performed the derivatisation step in polypropylene or borosilicate glass tubes over 45 min at 95 degrees C. High and obstructing background levels of benzaldehyde were found in one batch of polypropylene vials, as opposed to its alternatives. Treatment and handling of product shipment into the country did not account for introduction of contaminant into packaged vials nor did any reagent used in the assay. We conclude that the source of contamination was most likely due to variation in the commercial production process. Use of borosilicate vials for assays based on aldehyde production and derivatisation is recommended.
Journal of Chromatography B 12/2005; 826(1-2):277-8. · 2.89 Impact Factor
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Melinda Wong,
Ling Toh,
Andrew Wilson,
Kevin Rowley, Connie Karschimkus,
David Prior,
Evange Romas,
Laurence Clemens,
George Dragicevic,
Harry Harianto,
Ian Wicks,
Geoff McColl,
James Best,
Alicia Jenkins
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ABSTRACT: Rheumatoid arthritis (RA) is associated with increased rates of cardiovascular disease. Reduced small artery elasticity (SAE) and large artery elasticity (LAE) and increased systemic vascular resistance (SVR) have been found in other high-risk groups. In the present study, we sought to determine whether arterial elasticity was reduced and SVR was increased in RA patients compared with controls matched for coronary artery disease (CAD) status, and to relate the results to vascular disease risk factors, including measures of inflammation.
Arterial elasticity was assessed by pulse wave analysis in RA patients with (n = 15) and without (n = 38) CAD, and in controls matched 1:1 for age, sex, and CAD status. Vascular risk factors, including high-sensitivity C-reactive protein (hsCRP), soluble vascular cell adhesion molecule 1 (sVCAM-1), and serum amyloid A (SAA) levels, were assessed.
SAE and LAE were significantly lower and SVR was significantly higher in RA patients than in controls. RA patients also had higher levels of hsCRP, SAA, and sVCAM-1. SAE and LAE values were inversely correlated with markers of inflammation. Associations of SAE and LAE with RA were independent of conventional risk factors, but were dependent on markers of inflammation.
Vascular function is abnormal in RA, with reduced SAE and LAE and increased SVR relative to controls. Arterial elasticity is inversely associated with measures of inflammation. These measures may be clinically useful in the detection and monitoring of vascular disease in RA.
Arthritis & Rheumatism 02/2003; 48(1):81-9. · 7.87 Impact Factor
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ABSTRACT: Oxidative damage to circulating lipids and vascular tissues contributes to the initiation and progression of atherosclerosis. High density lipoprotein provides protection from atherosclerosis and the enzyme paraoxonase may contribute to this effect. The aim of the present study was to examine the trends in paraoxonase activity during the course of a community-directed life-style intervention, and relationships of paraoxonase activity to other coronary heart disease risk factors, in a cohort of Australian Aboriginal people.
Redox Report 02/2002; 7(5):304-7. · 1.73 Impact Factor
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ABSTRACT: The paraoxonase (PON) gene cluster maps to human chromosome 7q21-22. In the PON 1 gene, several polymorphisms in the promoter and coding regions have been identified and are known to influence gene expression levels. Promoter polymorphisms have been shown to have the strongest influence on paraoxonase activity levels. Paraoxonase, a high-density lipoprotein associated enzyme, protects lipoproteins from oxidation. Lipid oxidation may play an important role in the development of micro- and macrovascular disease. There is evidence that paraoxonase activity is reduced in patients with diabetes. We therefore hypothesise that PON 1genotypes influence paraoxonase activity levels and increase the risk of microvascular disease in type 1 diabetes. Genotyping of 156 Caucasian adolescents with diabetes for seven PON 1 polymorphisms was performed, including that of a novel PON 1 promoter polymorphism A(-1074)G. PON genotypes were related to paraoxonase and arylesterase activities and diabetes complication status. There was strong linkage disequilibrium between the PON 1 promoter polymorphisms. Both promoter and coding region polymorphisms strongly influenced activity levels and were associated with diabetes complications. PON 1 genotypes Leu/Leu 54, AA(-162) and GG(-1074) were associated with higher urinary albumin loss, while the genotype GG(-907) was protective for retinopathy.
Journal of Diabetes and its Complications 20(5):322-8. · 2.03 Impact Factor