39 results on '"Merlin C"'
Search Results
2. The postprandial actions of GLP-1 receptor agonists: The missing link for cardiovascular and kidney protection in type 2 diabetes.
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Thomas, Merlin C., Coughlan, Melinda T., and Cooper, Mark E.
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Recent clinical trials in people with type 2 diabetes have demonstrated beneficial actions on heart and kidney outcomes following treatment with GLP-1RAs. In part, these actions are consistent with improved glucose control and significant weight loss. But GLP-1RAs may also have additive benefits by improving postprandial dysmetabolism. In diabetes, dysregulated postprandial nutrient excursions trigger inflammation, oxidative stress, endothelial dysfunction, thrombogenicity, and endotoxemia; alter hormone levels; and modulate cardiac output and regional blood and lymphatic flow. In this perspective, we explore the actions of GLP-1RAs on the postprandial state and their potential role in end-organ benefits observed in recent trials. Treatment with GLP-1RAs has been associated with beneficial actions on heart and kidney outcomes in recent clinical trials. Beyond improvements in glucose control and significant weight loss, Thomas et al. argue that the GLP-1RAs may also have additive benefits by improving postprandial dysmetabolism in people with type 2 diabetes. [ABSTRACT FROM AUTHOR]
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- 2023
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3. Targeting the Pathobiology of Diabetic Kidney Disease.
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Thomas, Merlin C.
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- 2021
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4. Assessing problem solving in expert systems using human benchmarking
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O'Neil, Harold F. Jr., Ni, Yujing, Baker, Eva L., and Wittrock, Merlin C.
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Expert systems -- Evaluation ,Information technology -- Evaluation ,Problem solving -- Evaluation ,Expert system development software ,Information technology ,Computers ,Psychology and mental health ,Sociology and social work - Abstract
A correspondence between functions of the expert system GATES and human problem solving skills to perform a scheduling task is studied. This study supports the feasibility of using human benchmarking methodology to evaluate the problem solving ability of a specific expert system.
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- 2002
5. Observation of a 27-day solar signature in noctilucent cloud altitude.
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Köhnke, Merlin C., von Savigny, Christian, and Robert, Charles E.
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SOLAR activity , *MESOSPHERE , *THERMOSPHERE , *SOLAR radiation , *SCATTERING (Physics) - Abstract
Previous studies have identified solar 27-day signatures in several parameters in the Mesosphere/Lower thermosphere region, including temperature and Noctilucent cloud (NLC) occurrence frequency. In this study we report on a solar 27-day signature in NLC altitude with peak-to-peak variations of about 400 m. We use SCIAMACHY limb-scatter observations from 2002 to 2012 to detect NLCs. The superposed epoch analysis method is applied to extract solar 27-day signatures. A 27-day signature in NLC altitude can be identified in both hemispheres in the SCIAMACHY dataset, but the signature is more pronounced in the northern hemisphere. The solar signature in NLC altitude is found to be in phase with solar activity and temperature for latitudes ≳ 70 ° N. We provide a qualitative explanation for the positive correlation between solar activity and NLC altitude based on published model simulations. [ABSTRACT FROM AUTHOR]
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- 2018
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6. Multimodal quantification and validation of 3D regional myocardial function.
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Beitone, C., Bianchi, K., Bouges, P., Stoica, R., Tuyisenge, V., Cassagnes, L., Chausse, F., Clarysse, P., Clerfond, G., Croisille, P., Merlin, C., Pousin, J., Tilmant, C., Vacavant, A., and Sarry, L.
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MYOCARDIUM physiology ,THREE-dimensional imaging ,CARDIAC imaging ,ECHOCARDIOGRAPHY ,CARDIOLOGY - Abstract
The aim of this project is to design a generic formalism for parietal and regional tracking of the left ventricle (LV) and to adapt it to 3 D + t cardiac imaging modalities used in clinical routine (echocardiography, gated-SPECT, cine-MRI). The estimated displacement field must be reliable enough and insensitive to various artifacts to assess regional myocardial function in 3D from the accurate and precise computation of strain. The strain has recently proved to be of great interest for diagnosis and prognostic in cardiology, but its interpretation remains difficult because of the relative nature of the indices. The clinical objective of the 3DStrain project is to bring answers about the knowledge of normality. [ABSTRACT FROM AUTHOR]
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- 2015
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7. ACE2 deficiency shifts energy metabolism towards glucose utilization.
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Bernardi, Stella, Tikellis, Christos, Candido, Riccardo, Tsorotes, Despina, Pickering, Raelene J., Bossi, Fleur, Carretta, Renzo, Fabris, Bruno, Cooper, Mark E., and Thomas, Merlin C.
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ACE inhibitors ,ENZYME deficiency ,ENERGY metabolism ,HOMEOSTASIS ,REVERSE transcriptase polymerase chain reaction ,IMMUNOSTAINING - Abstract
Background This study aimed at investigating the effects of genetic angiotensin-converting enzyme (ACE) 2 deficiency on glucose homeostasis in the pancreas and skeletal muscle and their reversibility following ACE inhibition. Procedures ACE2 -knockout and C57bl6J mice were placed on a standard diet (SD) or a high-fat diet (HFD) for 12 weeks. An additional group of ACE2 -knockout mice was fed a SD and treated with the ACE inhibitor, perindopril (2 mg kg − 1 day − 1 ). Glucose and insulin tolerance tests, indirect calorimetry measurements and EchoMRI were performed. Non-esterfied ‘free’ fatty acid oxidation rate in skeletal muscle was calculated by measuring the palmitate oxidation rate. β-cell mass was determined by immunostaining. Insulin, collectrin, glucose transporter protein, and peroxisome proliferator-activated receptor-γ expression were analysed by RT-PCR. Markers of mithocondrial biogenesis/content were also evaluated. Main Findings ACE2 -knockout mice showed a β-cell defect associated with low insulin and collectrin levels and reduced compensatory hypertrophy in response to a HFD, which were not reversed by perindopril. On the other hand, ACE2 deficiency shifted energy metabolism towards glucose utilization, as it increased the respiratory exchange ratio, reduced palmitate oxidation and PCG-1α expression in the skeletal muscle, where it up-regulated glucose transport proteins. Treatment of ACE2 -knockout mice with perindopril reversed the skeletal muscle changes, suggesting that these were dependent on Angiotensin II (Ang II). Principal Conclusions ACE2 -knockout mice display a β-cell defect, which does not seem to be dependent on Ang II but may reflect the collectrin-like action of ACE2. This defect seemed to be compensated by the fact that ACE2 -knockout mice shifted their energy consumption towards glucose utilisation via Ang II. [ABSTRACT FROM AUTHOR]
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- 2015
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8. Glycemic Exposure, Glycemic Control, and Metabolic Karma in Diabetic Complications.
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Thomas, Merlin C.
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- 2014
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9. EP07.01-024 Preclinical Investigation of Immune Checkpoint Blockade and Anti-Angiogenic Therapy in Malignant Pleural Mesothelioma.
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Rovers, S., Merlin, C., Fisher, S., Nowak, A., Pauwels, P., Lardon, F., van Meerbeeck, J., Smits, E., and Marcq, E.
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- 2022
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10. Post-translational modification of plant-made foreign proteins; glycosylation and beyond
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Webster, Diane E. and Thomas, Merlin C.
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POST-translational modification , *PROTEIN engineering , *EUKARYOTIC cells , *GLYCOSYLATION , *HYDROXYLATION , *PLANT engineering , *INTERFERONS , *TRANSFERASES , *SIALIC acids - Abstract
Abstract: The complex and diverse nature of the post-translational modification (PTM) of proteins represents an efficient and cost-effective mechanism for the exponential diversification of the genome. PTMs have been shown to affect almost every aspect of protein activity, including function, localisation, stability, and dynamic interactions with other molecules. Although many PTMs are evolutionarily conserved there are also important kingdom-specific modifications which should be considered when expressing recombinant proteins. Plants are gaining increasing acceptance as an expression system for recombinant proteins, particularly where eukaryotic-like PTMs are required. Glycosylation is the most extensively studied PTM of plant-made recombinant proteins. However, other types of protein processing and modification also occur which are important for the production of high quality recombinant protein, such as hydroxylation and lipidation. Plant and/or protein engineering approaches offer many opportunities to exploit PTM pathways allowing the molecular farmer to produce a humanised product with modifications functionally similar or identical to the native protein. Indeed, plants have demonstrated a high degree of tolerance to changes in PTM pathways allowing recombinant proteins to be modified in a specific and controlled manner, frequently resulting in a homogeneity of product which is currently unrivalled by alternative expression platforms. Whether a recombinant protein is intended for use as a scientific reagent, a cosmetic additive or as a pharmaceutical, PTMs through their presence and complexity, offer an extensive range of options for the rational design of humanised (biosimilar), enhanced (biobetter) or novel products. [Copyright &y& Elsevier]
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- 2012
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11. The assessment and management of albuminuria in primary care
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Thomas, Merlin C.
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ALBUMINURIA , *TYPE 2 diabetes , *CARDIOVASCULAR diseases , *KIDNEY disease diagnosis - Abstract
Abstract: Background: While CKD is a common finding in patients with type 2 diabetes, the clinical response to its identification is often problematic. This study aims to determine the frequency of albuminuria in patients with type 2 diabetes in the primary care setting and examine the factors which influence its management. Methods: Expressions of interest were invited from all registered GPs across Australia, from whom 500 investigators were randomly selected. Investigators were requested to document the clinical characteristics of 10–15 consecutively presenting patients with type 2 diabetes. Results from the most recent urinalysis were classified according to guidelines, then systematically compared to classifications provided by GPs themselves and their management strategies. Results: One in three patients had an elevated urinary albumin excretion (UAE, 34.6%, 95% CI, 33.3–35.9%) on their most recent urinalysis. The presence of microalbuminuria or proteinuria, as identified by the GP, was not associated with a perceived increase in cardiovascular risk. In addition, the use of aspirin and the prescribing of agents to block the RAS were not significantly linked to UAE. Similarly, the perceived adequacy of blood pressure control was not significantly different whether or not microalbuminuria or proteinuria was identified to be present. Conclusion: An elevated UAE is a common finding in general practice. However, it fails to significantly influence their clinical care. Additional education to ensure appropriate case recognition and management of kidney disease is needed, focusing on the significance of albuminuria to the care of patients with type 2 diabetes. [Copyright &y& Elsevier]
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- 2008
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12. Can you reduce your AGE?: Strategies to prevent AGE accumulation in diabetes.
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Coughlan, Melinda T., Cooper, Mark E., and Thomas, Merlin C.
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DIABETES ,CARBOHYDRATE intolerance ,PEOPLE with diabetes ,CHRONICALLY ill - Abstract
Advanced glycation end-products (AGEs) contribute to the development and progression of diabetic kidney disease. Several different strategies have been developed to prevent the accumulation of AGEs in experimental diabetes, many of which have proved highly effective in attenuating renal damage in experimental models, even the absence of blood glucose control. These data suggests that if AGEs can be directly treated, some of the complications of diabetes may also be prevented. [Copyright &y& Elsevier]
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- 2007
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13. The High Prevalence of Anemia in Diabetes Is Linked to Functional Erythropoietin Deficiency.
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Thomas, Merlin C.
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DIABETES ,ANEMIA ,DISEASE prevalence ,ERYTHROPOIETIN ,HEMOGLOBINS ,DIABETIC nephropathies ,RETROLENTAL fibroplasia ,DISEASE risk factors - Abstract
Anemia is a common finding in diabetes, particularly in patients with albuminuria or renal impairment. We recently showed that at least 1 in 5 outpatients with type 1 or type 2 diabetes in tertiary clinics have anemia, in whom it constitutes a significant additional burden. Anemia is associated strongly with an increased risk of diabetic complications including nephropathy, retinopathy, and heart failure. Although a number of factors contribute to an increased prevalence of anemia in diabetes, an uncoupling of hemoglobin concentration and renal erythropoietin synthesis associated with tubular dysfunction appears to be the dominant factor. In our patients with diabetes and anemia, more than three quarters had functional erythropoietin deficiency. This association was most pronounced in patients with renal impairment, in whom nearly half of all patients had anemia. However, 70% of anemic patients without renal impairment also had inappropriately low erythropoietin levels. Consequently, the likelihood of functional erythropoietin deficiency, as a cause of anemia in patients with diabetes, is not dependent on the severity of renal impairment. Although there is a clear rationale for correction of anemia in diabetes, it remains to be established whether this will lead to improved outcomes. Some small studies suggest improvement in cardiac outcomes and hospitalization. It is anticipated that large ongoing studies will help define the optimal approach to the management of anemia in diabetes. [ABSTRACT FROM AUTHOR]
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- 2006
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14. Glycated and carboxy-methylated proteins do not directly activate human vascular smooth muscle cells.
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Ballinger, Mandy L., Thomas, Merlin C., Nigro, Julie, Ivey, Melanie E., Dilley, Rodney J., and Little, Peter J.
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DIABETES , *VASCULAR smooth muscle , *PROTEOGLYCANS , *GLUCOSE synthesis , *GLUCOSE , *PROTEIN synthesis , *ATHEROSCLEROSIS , *HYPERGLYCEMIA - Abstract
Background. Advanced glycation end products (AGEs) accumulate in patients with diabetes, particularly at sites of vascular damage and within atherosclerotic lesions, but whether they have direct actions on vascular smooth muscle cells (VSMCs) is controversial. Methods. AGEs were constructed and characterized by protein content, level of modification, fluorescence, and molecular size. Human VSMCs were derived from different vascular beds. Glucose consumption, de novo protein synthesis, and proteoglycan biosynthesis were measured using a colorimetric assay and metabolic radiolabeling. Receptor for AGEs (RAGE) expression was assessed by real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. Results. Treatment with AGEs under low or high glucose conditions showed no change in cellular glucose consumption or in cellular protein synthesis under low glucose conditions. Treatment of VSMCs with Nε-(carboxymethyl)lysine in the presence of low glucose increased [35S]-sulfate incorporation into secreted proteoglycans by 72% ( P < 0.001) and 67% ( P < 0.001); however, the control proteins also increased [35S]-sulfate incorporation into proteoglycans by 56% ( P < 0.01), with similar effects observed under high glucose conditions. Human VSMCs showed no difference in response to glycated and non-glycated protein. Protein and gene expression of RAGE in VSMC was approximately 50-fold lower compared to HMEC-1 and U937 cells, consistent with the immunohistochemical staining of RAGE in vivo. Conclusion. VSMCs show very low levels of RAGE expression; thus, activation of VSMCs by AGEs does not occur. In diabetes, RAGE expression in VSM may increase to the extent that it becomes activated by AGEs in a manner that would contribute to the process of atherosclerosis. [ABSTRACT FROM AUTHOR]
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- 2005
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15. Increased tubular organic ion clearance following chronic ACE inhibition in patients with type 1 diabetes.
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Thomas, Merlin C., Jerums, George, Tsalamandris, Con, MacIsaac, Richard, Panagiotopoulos, Sianna, and Cooper, Mark E.
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ANGIOTENSIN converting enzyme , *EXCRETION , *DIABETES , *ENDOCRINE diseases , *CARBOHYDRATE intolerance , *KIDNEY diseases , *PYRIDINE , *CATION metabolism , *GLOMERULAR filtration rate , *HIGH performance liquid chromatography , *TYPE 1 diabetes , *ACE inhibitors , *RENIN-angiotensin system , *KIDNEY tubules , *TREATMENT effectiveness , *COMPARATIVE studies , *PLACEBOS , *RANDOMIZED controlled trials , *DESCRIPTIVE statistics , *RENAL circulation , *BIOTRANSFORMATION (Metabolism) , *BENZAMIDE , *STATISTICAL sampling , *CREATININE , *NIFEDIPINE , *ALBUMINURIA , *PHARMACODYNAMICS , *EVALUATION - Abstract
Increased tubular organic ion clearance following chronic ACE inhibition in patients with type 1 diabetes.Background.The tubular excretion of creatinine significantly contributes to its clearance. Administration of an angtiotensin-converting enzyme (ACE) inhibitor is associated with increased organic ion clearance in experimental diabetes. This study examines the effect and implications of chronic ACE inhibition on renal organic ion excretion in patients with type 1 diabetes.Methods.Samples were obtained from the Melbourne Diabetic Nephropathy Study Group (MDNSG) that randomized patients to receive perindopril (N= 11), nifedipine (N= 11), or placebo (N= 8). Albumin excretion rate, creatinine clearance, and isotopic glomerular filtration rate (GFR) were assessed at baseline and after 24 months. In addition, the clearance of the endogenous cations N-methylynicotinamide (NMN), creatinine, and the anion hippurate were determined by high-performance liquid chromatography (HPLC).Results.Following treatment with the ACE inhibitor, perindopril, renal clearance of NMN was increased (+96%) (P<0.05). There was no difference in patients treated with nifedipine (P= 0.25) and NMN clearance fell in the placebo-treated patients (−26%) (P<0.05). Changes in NMN clearance were unaffected after adjusting for the effects of perindopril on GFR. However, they were attenuated after adjusting for hippurate clearance, a marker of renal blood flow. This effect of perindopril on NMN clearance was seen in both men and women, regardless of baseline clearance and was correlated with reduced albuminuria following perindopril treatment.Conclusion.Organic ion clearance is increased in patients with diabetes following chronic ACE inhibition. This is consistent with experimental models showing increased ion transporter expression and improved tubular blood flow, following blockade of the renin-angiotensin system (RAS). These findings may have implications for the interpretation of creatinine-based indices in patients with diabetes. [ABSTRACT FROM AUTHOR]
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- 2005
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16. Low-molecular-weight AGEs are associated with GFR and anemia in patients with type 2 diabetes.
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Thomas, Merlin C., Tsalamandris, Con, MacIsaac, Richard, Medley, Tanya, Kingwell, Bronwyn, Cooper, Mark E., and Jerums, George
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DIABETIC nephropathies , *DIABETES complications , *KIDNEY diseases , *NEPHROLOGY , *DIABETES , *MULTIVARIATE analysis - Abstract
Low-molecular-weight AGEs are associated with GFR and anemia in patients with type 2 diabetes. Background. Advanced glycation end products (AGEs) are implicated in the development and progression of diabetic nephropathy. We examined the predictors of low-molecular-weight (LMW) AGEs in a cross-sectional survey of 604 patients with type 2 diabetes in a single clinic. Methods. A clinical history and results of routine blood and urine testing were obtained for all patients over a 2-year period. Fluorescent LMW AGEs were estimated in serum samples taken concurrently, using an established flow injection method. Predictors of LMW AGEs were identified using multiple regression analysis. Results. LMW AGEs were 34% higher in patients with diabetes than nondiabetic volunteers from the same community ( P < 0.001). Independent predictors for LMW AGEs in patients with diabetes were glomerular filtration rate (GFR) and hemoglobin (both P < 0.001). While patients with renal impairment and anemia had the highest levels of LMW AGEs, both GFR and hemoglobin remained predictive when patients with a serum creatinine or hemoglobin within the “normal range” were analyzed separately. Patients with hyperfiltration had significantly lower LMW AGEs than those with normal renal function. Gender was also a significant independent predictor of LMW AGEs in patients without anemia. However, LMW AGEs were not associated with metabolic control or the presence of macrovascular disease. Conclusion. Circulating levels of LMW AGEs are elevated in patients with diabetes, especially those with impaired renal function or anemia. These findings extend the evidence for an association between AGEs and progressive renal injury in patients with type 2 diabetes. Whether LMW AGEs contribute to, or are a marker of, renal damage needs to be established by prospective studies. [ABSTRACT FROM AUTHOR]
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- 2004
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17. Reduced tubular cation transport in diabetes: Prevented by ACE inhibition.
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Thomas, Merlin C., Tikellis, Chris, Burns, Wendy C., Thallas, Vicki, Forbes, Josephine M., Cao, Zemin, Osicka, Tanya M., Russo, Leileata M., Jerums, George, Ghabrial, Hany, Cooper, Mark E., and Kantharidis, Phillip
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DIABETES , *KIDNEY tubules , *ACE inhibitors - Abstract
Reduced tubular cation transport in diabetes: Prevented by ACE inhibition. Background. The renal clearance of organic cations is important for the homeostasis of a number of exogenous and endogenous compounds. The organic cation transporters (OCTs) situated on the basolateral surface of proximal tubular cells mediate active cation excretion. Alterations of cation transport may occur in diabetes, although the role of the OCTs has not been previously assessed. Methods. Experimental diabetes was induced in rats with streptozotocin (55 mg/kg) and animals were randomly assigned to receive ramipril (3 mg/mL) in drinking water for 24 weeks. In a second protocol, rats were infused with angiotensin II (Ang II) at a dose of 58.3 ng/kg/min for 2 weeks via an implanted osmotic pump. Expression of the OCTs and renal clearance of the endogenous cation N -methyl-nicotinamide (NMN) was assessed. Results. Diabetes was associated with a reduction in gene and protein expression of both OCT-1 and OCT-2 and a reduction in NMN clearance. These effects were prevented by ramipril, associated with the prevention of albuminuria and tubular injury as demonstrated by the expression of osteopontin and glutathione peroxidase 3 (GPX-3). An infusion of Ang II also reduced NMN clearance but without altering the renal expression of OCTs. Conclusion. We hypothesize that reduced expression of OCTs in diabetes may be a marker of tubular injury. However, Ang II may also directly augment renal cation clearance independent of changes in transporter expression. Together these effects may provide additional mechanism to explain treatment-related improvements in creatinine clearance and renoprotection in diabetes following blockade of the renin-angiotensin system (RAS). [ABSTRACT FROM AUTHOR]
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- 2003
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18. Low fibrosis biomarker levels predict cardiac resynchronization therapy response.
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Massoullie, G., Sapin, V., Ploux, S., Rossignol, P., Mulliez, A., Jean, F., Marie, P.Y., Merlin, C., Pereira, B., Andronache, M., Motreff, P., Chabin, X., Sellal, J.M., Citron, B., Lusson, J.R., Vorilhon, C., Clerfond, G., Bordachar, P., Zannad, F., and Eschalier, R.
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Cardiac fibrosis is associated with heart failure and poor prognosis. Fibrosis biomarkers have been poorly evaluated as a tool to predict cardiac resynchronization therapy (CRT) response generating conflicting results. The present study assessed the predictive value of cardiac fibrosis biomarkers on CRT response. Patients underwent clinical examination, echocardiography and blood fibrosis biomarker evaluation prior to CRT implantation. At six months, a positive response to CRT was defined by a composite endpoint of no death or hospitalization for heart failure, and presence of left ventricular (LV) reverse remodeling (decrease in LV end-systolic volume ≥ 15%). Sixty patients were included in a multicenter study. At 6 months, 38 were positive responders to CRT and reached the response criteria (63%). Compared to non-responders, CRT responders displayed lower concentration levels of the fibrosis biomarkers procollagen type I C-terminal propeptide [PICP 135[99–166] ng/ml vs. 179[142–226] ng/ml, (P = 0.001)] and procollagen type III N-terminal propeptide [PIIINP 5.50[3.66–8.96] ng/ml vs. 8.01[5.01–11.86]ng/ml, (P = 0.014)] at baseline. In multivariate analysis, a PICP ≤ 163 ng/ml was associated with a positive CRT response [OR = 7.8(1.3–46.7), P = 0.023] independently of the presence of LBBB, QRS duration, LV lead position or non-ischemic cardiomyopathy. Altogether, the present findings show that a lower degree of cardiac fibrosis is associated with a positive response after CRT implantation. PICP evaluation before CRT implantation could help improve patient selection. [ABSTRACT FROM AUTHOR]
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- 2020
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19. Taxis-driven pattern formation in a predator-prey model with group defense.
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Köhnke, Merlin C., Siekmann, Ivo, and Malchow, Horst
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PREDATION ,ECOLOGICAL models ,MAGNITUDE (Mathematics) ,OSCILLATIONS ,DATA modeling ,GASKETS - Abstract
We consider a reaction-diffusion(-taxis) predator-prey system with group defense in the prey. Taxis-driven instability can occur if the group defense influences the taxis rate (Wang et al., 2017). We elaborate that this mechanism is indeed possible but biologically unlikely to be responsible for pattern formation in such a system. Conversely, we show that patterns in excitable media such as spatiotemporal Sierpinski gasket patterns occur in the reaction-diffusion model as well as in the reaction-diffusion-taxis model. If group defense leads to a dome-shaped functional response, these patterns can have a rescue effect on the predator population in an invasion scenario. Preytaxis with prey repulsion at high prey densities can intensify this mechanism leading to taxis-induced persistence. In particular, taxis can increase parameter regimes of successful invasions and decrease minimum introduction areas necessary for a successful invasion. Last, we consider the mean period of the irregular oscillations. As a result of the underlying mechanism of the patterns, this period is two orders of magnitude smaller than the period in the nonspatial system. Counter-intuitively, faster-moving predators lead to lower oscillation periods and eventually to extinction of the predator population. The study does not only provide valuable insights on theoretical spatially explicit predator-prey models with group defense but also comparisons of ecological data with model simulations. [ABSTRACT FROM AUTHOR]
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- 2020
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20. Dialysis delayed is death prevented: A clinical perspective on the RENAAL study.
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Thomas, Merlin C., Cooper, Mark E., Shahinfar, Shahnaz, and Brenner, Barry M.
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CHRONIC kidney failure , *PREVENTION - Abstract
Comments on the prevention of end-stage renal disease (ESRD) in the U.S. Factors contributing to the decline in the renal function rate; Proportion of time spent on conservative therapy; Cost of ESRD treatment.
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- 2003
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21. Low cardiac fibrosis biomarkers levels predict cardiac resynchronization therapy response.
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Massoullié, G., Sapin, V., Ploux, S., Zannad, F., Mulliez, A., Jean, F., Marie, P.Y., Merlin, C., Pereira, B., Andronnache, M., Motreff, P., Vorilhon, C., Clerfond, G., Rossignol, P., Bordachar, P., and Eschalier, R.
- Abstract
Introduction Cardiac fibrosis is associated to heart failure and poor prognosis. Cardiac fibrosis biomarkers have not been evaluated to predict cardiac resynchronization therapy (CRT) response. Methods Patient included according to CRT European guidelines underwent before CRT implantation clinical examination, functional test, electrocardiogram, echocardiography and blood fibrosis biomarkers evaluation. At six months, positive response to CRT was defined with a composite endpoint: no death, nor hospitalization for a cardiac cause, and presence of a left ventricular (LV) reverse remodelling (decrease in LV end-systolic volume ≥ 15%). Results A total of 60 patients were consecutively included in a multicenter study. At 6 months, 38 were positive responders to CRT and reach the composite response criteria (63%). In the CRT responders group compared to non-responders, we observed a longer QRS duration (171 ± 22 ms vs 150 ± 21 ms, P < 0.001), more left-bundle branch block (LBBB) (58% vs 25%, P < 0.001), non-ischemic cardiomyopathy (75% vs 30%, P = 0.02), and a lower fibrosis biomarker concentration procollagen type I C-terminal propeptide (PICP [139 ± 53 ng/ml vs 93 ± 87 ng/ml, P = 0.005]). PICP was inversely correlated to LV reverse remodelling ( r 2 = 0.38, P = 0.005) and was significantly higher in CRT non-responders patients despite a LBBB (268 ± 158 ng/ml vs 129 ± 53 ng/ml, P < 0.001) or a non-ischemic cardiomyopathy (232 ± 90 ng/ml vs 142 ± 57 ng/ml, P < 0.001). In multivariate analysis, a PICP ≤ 163 ng/ml was associated to CRT response [OR = 15 (2.3–106), P = 0.03] ( Fig. 1 ). Conclusion A lower degree of cardiac fibrosis is associated to positive response after CRT implantation. PICP evaluation before CRT implantation may improve patient selection usually only based on electrical asynchronism and LV function. [ABSTRACT FROM AUTHOR]
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- 2018
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22. Interactions between growth factors in the kidney: Implications for progressive renal injury.
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Cooper, Mark E. and Thomas, Merlin C.
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GROWTH factors , *KIDNEY diseases - Abstract
Editorial. Examines the role of growth factors in the development and progression of renal disease. Relationship between insulin-like growth factor-1 and vascular endothelial growth factor; Activation of the nonreceptor tyrosine kinase pathways by a diverse range of mitogens.
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- 2003
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23. Targeting advanced glycation in obesity related renal dysfunction.
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Harcourt, Brooke E., Sourris, Karly C., Coughlan, Melinda T., Walker, Karen Z., Morley, Amy L., Penfold, Sally, Thomas, Merlin C., Kingwell, Bronwyn A., Cooper, Mark E., De Courten, Barbora, and Forbes, Josephine M.
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- 2010
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24. The effects of valsartan on the accumulation of circulating and renal advanced glycation end products in experimental diabetes.
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Forbes, Josephine M., Thomas, Merlin C., Thorpe, Suzanne R., Alderson, Nathan L., and Cooper, Mark E.
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EXPERIMENTAL diabetes , *EXPERIMENTAL medicine , *GLYCOSYLATED hemoglobin , *CARBOHYDRATE intolerance , *GLYCEMIC control - Abstract
The effects of valsartan on the accumulation of circulating and renal advanced glycation end products in experimental diabetes. Background Blockade of the RAS with the ACE inhibitor ramipril prevents the accumulation of advanced glycation end products (AGEs) in experimental diabetes. Although AT 1 receptor antagonists may inhibit AGE formation in vitro, their effect in normotensive animals with type 1 diabetes has not been established. Methods Streptozotocin-induced diabetic and control animals were randomized ( N =10/group) to receive the AT 1 antagonist valsartan at a dose of 30 mg/kg/day by oral gavage for 24 weeks, or no intervention. Renal and plasma AGE accumulation was correlated with renal functional parameters. Results Valsartan reduced the albumin excretion rate consistent with its renoprotective effects. Renal and skin collagen accumulation of the non-fluorescent AGE carboxymethyllysine (CML) were increased in animals with diabetes, but normalized following treatment with valsartan. Renal fluorescence and skin collagen pentosidine levels were also increased by diabetes. However, valsartan only provided a modest attenuation of these parameters. In addition, diabetes was associated with increased plasma fluorescence, which was unaffected by AT 1 antagonism. Conclusion Renoprotective doses of valsartan are associated with a significant reduction in the accumulation of tissue and plasma CML. These effects were not the same for all AGEs, suggesting combination approaches will be required to optimize renoprotection in diabetes. [ABSTRACT FROM AUTHOR]
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- 2004
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25. Angiotensin converting enzyme 2 and atherosclerosis
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Wang, Yutang, Tikellis, Chris, Thomas, Merlin C., and Golledge, Jonathan
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ANGIOTENSIN converting enzyme , *ATHEROSCLEROSIS , *RENIN-angiotensin system , *DISEASE progression , *MOLECULAR biology , *ANIMAL models in research - Abstract
Abstract: Angiotensin converting enzyme 2 (ACE2) is a homolog of angiotensin converting enzyme (ACE) which generates angiotensin II from angiotensin I. ACE, its product angiotensin II and the downstream angiotensin type I receptor are important components of the renin–angiotensin system (RAS). Angiotensin II, the most important component of the RAS, promotes the development of atherosclerosis. The identification of ACE2 in 2000 opened a new chapter of research on the regulation of the RAS. ACE2 degrades pro-atherosclerotic angiotensin II and generates anti-atherosclerotic angiotensin 1–7. In this review, we explored the importance of ACE2 in protecting experimental animals from developing atherosclerosis and its involvement in human atherosclerosis. We also examined the published evidence assessing the importance of ACE2 in different cell types relevant to atherosclerosis and putative underlying cellular and molecular mechanisms linking ACE2 with protection from atherosclerosis. ACE2 shifts the balance from angiotensin II to angiotensin 1–7 inhibiting the progression of atherosclerosis in animal models. [Copyright &y& Elsevier]
- Published
- 2013
- Full Text
- View/download PDF
26. An acute fall in estimated glomerular filtration rate during treatment with losartan predicts a slower decrease in long-term renal function.
- Author
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Holtkamp, Frank A., de Zeeuw, Dick, Thomas, Merlin C., Cooper, Mark E., de Graeff, Pieter A., Hillege, Hans J. L., Parving, Hans-Henrik, Brenner, Barry M., Shahinfar, Shahnaz, and Lambers Heerspink, Hiddo J.
- Subjects
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GLOMERULAR filtration rate , *LOSARTAN , *KIDNEY diseases , *REGULATION of blood pressure , *DRUG administration - Abstract
Intervention in the renin-angiotensin-aldosterone-system (RAAS) is associated with slowing the progressive loss of renal function. During initiation of therapy, however, there may be an acute fall in glomerular filtration rate (GFR). We tested whether this initial fall in GFR reflects a renal hemodynamic effect and whether this might result in a slower decline in long-term renal function. We performed a post hoc analysis of the Reduction of Endpoints in Non-Insulin-Dependent Diabetes Mellitus with the Angiotensin II Antagonist Losartan (RENAAL) trial. Patients assigned to losartan had a significantly greater acute fall in estimated (eGFR) during the first 3 months compared to patients assigned to placebo, but a significantly slower long-term mean decline of eGFR thereafter. A large interindividual difference, however, was noticed in the acute eGFR change. When patients were divided into tertiles of initial fall in eGFR, the long-term eGFR slope calculated from baseline was significantly higher in patients with an initial fall compared to those with an initial rise. When eGFR decline was calculated from 3 months to the final visit, excluding the initial effect, patients with a large initial fall in eGFR had a significant lower long-term eGFR slope compared to those with a moderate fall or rise. This relationship was independent of other risk markers or change in risk markers for progression of renal disease such as blood pressure and albuminuria. Thus, the greater the acute fall in eGFR, during losartan treatment, the slower the rate of long-term eGFR decline. Hence, interpretation of trial results relying on slope-based GFR outcomes should separate the initial drug-induced GFR change from the subsequent long-term effect on GFR. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
27. Targets to retard the progression of diabetic nephropathy.
- Author
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Cooper, Mark E., Jandeleit-Dahm, Karin, and Thomas, Merlin C.
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- *
HEALTH surveys , *PEOPLE with diabetes , *DIABETES , *TYPE 2 diabetes , *DIABETIC nephropathies - Abstract
Reports on the estimated number of people worldwide who will have diabetes by the year of 2025, according to the World Health Organization. Percentage of newly diagnosed patients with type 2 diabetes; Development of diabetic nephropathy; Total number of people with type 1 diabetes.
- Published
- 2005
- Full Text
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28. 1651P Characteristics, tolerance and effectiveness of patients aged more or less than 75 years treated with [177Lu]Lu-PSMA-617 as part of France's early access program.
- Author
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Tonnelet, D., Farce, J., Agrigoroaie, L., Merlin, C., Cottereau, A-S., Chene, S., Bailly, C., Bros, M., Mourey, L., and Lacombe, M.
- Subjects
- *
AGE - Published
- 2024
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29. Pièges diagnostiques d’un syndrome d’activation macrophagique.
- Author
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Penel-Page, M., Ben Said, B., Phan, A., Hees, L., Hartmann-Merlin, C., Girard, S., Gillet, Y., and Belot, A.
- Abstract
Résumé Le syndrome d’activation macrophagique (SAM) est une situation clinique rare et sévère. Chez l’enfant, on distingue les SAM primitifs (dans le cadre d’une lymphohistiocytose familiale) des SAM secondaires, principalement liés aux maladies rhumatismales comme l’arthrite juvénile idiopathique de forme systémique, et parfois à des hémopathies malignes ou des infections sévères (virus d’Ebstein-Barr, leishmaniose). Nous rapportons le cas d’une patiente sans antécédent ayant développé à l’âge de 3 ans une ostéite maxillaire à Pseudomonas aeruginosa qui, après 2 semaines de traitement, s’est compliquée d’un SAM. La rareté de ce type d’infection, les caractéristiques du germe et la survenue d’une hémophagocytose ont initialement fait craindre un déficit immunitaire, une hémopathie ou une maladie systémique. Une corticothérapie (2 mg/kg/jour) a permis une régression complète des signes cliniques et biologiques et l’antibiothérapie a été poursuivie sans modification. Quelques jours après l’arrêt des corticoïdes, une érythrodermie est survenue. Une biopsie cutanée identifiant des éosinophiles et la revue rétrospective des numérations retrouvant une hyperéosinophilie relative et transitoire (0,98 G/L) au moment du SAM ont permis de faire a posteriori le diagnostic d’hypersensibilité médicamenteuse ( drug reaction with eosinophilia and systemic symptoms [DRESS]) . L’arrêt des antibiotiques en cause a permis une normalisation des symptômes sans reprise de corticoïdes. Les patch-tests à distance ont confirmé l’allergie à la pipéracilline. Cette observation permet de rappeler que le syndrome d’hypersensibilité médicamenteuse fait partie des causes de SAM. Summary Hemophagocytic lymphohistiocytosis (HLH) is a rare and severe syndrome usually associated with a cytotoxicity deficiency, which leads to an excess of immune response driven by activated macrophages and cytotoxic T cells. In children, HLH can be genetic, as part of a familial lymphohistiocytosis, or secondary: the most frequent causes are systemic-onset juvenile idiopathic arthritis, hematological malignancies, and severe infections, especially with Ebstein-Barr virus or leishmaniosis. We report on the case of a 3-year-old girl with no past medical history, who presented inaugural Pseudomonas aeruginosa maxillary osteitis, with secondary HLH. The rarity of this osteitis, the characteristics of the pathogen, and the onset of HLH oriented the diagnosis toward primary immunodeficiencies, malignancies, or systemic diseases. Steroids were initiated at 2 mg/kg/day and were very effective in improving the systemic symptoms. Antibiotic therapy was continued unchanged. A few days after discontinuation of steroids, while the patient was still under antibiotics, she presented with erythroderma. Skin biopsy revealed eosinophil infiltrate in line with the diagnosis of a drug reaction with eosinophilia and systemic symptoms (DRESS), even though we only observed very transient eosinophilia, up to 0.98 G/L, during HLH. Stopping antibiotics normalized the symptoms without using systemic corticosteroids. Patch tests confirmed an allergy to piperacillin. These atypical manifestations of DRESS underline that causative diagnosis of HLH is challenging, and DRESS syndrome should be considered. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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30. Pyridoxamine prevents increased atherosclerosis by intermittent methylglyoxal spikes in the aortic arches of ApoE-/- mice.
- Author
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Hanssen, Nordin M.J., Tikellis, Chris, Pickering, Raelene J., Dragoljevic, Dragana, Lee, Man Kit Sam, Block, Tomasz, Scheijen, Jean LJM, Wouters, Kristiaan, Miyata, Toshio, Cooper, Mark E., Murphy, Andrew J., Thomas, Merlin C., and Schalkwijk, Casper G.
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THORACIC aorta , *PYRUVALDEHYDE , *HYPERGLYCEMIA , *BLOOD sugar , *ATHEROSCLEROSIS , *TAKAYASU arteritis , *DRINKING water - Abstract
Methylglyoxal (MGO) is a reactive glucose metabolite linked to diabetic cardiovascular disease (CVD). MGO levels surge during intermittent hyperglycemia. We hypothesize that these MGO spikes contribute to atherosclerosis, and that pyridoxamine as a MGO quencher prevents this injury. To study this, we intravenously injected normoglycemic 8-week old male C57Bl6 ApoE-/- mice with normal saline (NS, n = 10) or 25 µg MGO for 10 consecutive weeks (MGO iv , n = 11) with or without 1 g/L pyridoxamine (MGO iv +PD, n = 11) in the drinking water. We measured circulating immune cells by flow cytometry. We quantified aortic arch lesion area in aortic roots after Sudan-black staining. We quantified the expression of inflammatory genes in the aorta by qPCR. Intermittent MGO spikes weekly increased atherosclerotic burden in the arch 1.8-fold (NS: 0.9 ± 0.1 vs 1.6 ± 0.2 %), and this was prevented by pyridoxamine (0.8 ± 0.1 %). MGO iv spikes increased circulating neutrophils and monocytes (2-fold relative to NS) and the expression of ICAM (3-fold), RAGE (5-fold), S100A9 (2-fold) and MCP1 (2-fold). All these changes were attenuated by pyridoxamine. This study suggests that MGO spikes damages the vasculature independently of plasma glucose levels. Pyridoxamine and potentially other approaches to reduce MGO may prevent excess cardiovascular risk in diabetes [Display omitted] [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
31. Quinapril treatment abolishes diabetes-associated atherosclerosis in RAGE/apolipoprotein E double knockout mice.
- Author
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Watson, Anna M. D., Jiaze Li, Samijono, Dian, Bierhaus, Angelika, Thomas, Merlin C., Jandeleit-Dahm, Karin A. M., and Cooper, Mark E.
- Subjects
- *
ATHEROSCLEROSIS treatment , *QUINAPRIL , *APOLIPOPROTEIN E , *ENZYME inhibitors , *NITROTYROSINE , *LABORATORY mice , *RENIN-angiotensin system , *THERAPEUTICS - Abstract
Objective/Rationale Both the renin-angiotensin system (RAS) and the receptor for advanced glycation end products (RAGE) potentiate diabetes-associated atherosclerosis (DAA). We assessed the effectiveness of concomitant RAS and RAGE inhibition on DAA. Methods Diabetic (5 x 55 mg/kg streptozotocin daily) and non-diabetic male RAGE/apolipoprotein E double knockout (RAGE/apoE DKO) mice were treated with quinapril (30 mg/kg/day) for 20 weeks. At the end of the study aortic plaques were assessed. Results Diabetic RAGE/apoE DKO showed significantly less plaque area than diabetic apoE KO mice. Plaque deposition was almost abolished in quinapril treated diabetic RAGE/apoE DKOs, with significant attenuation of vascular collagen deposition, nitrotyrosine staining, and reduced macrophage infiltration. Expression of the advanced glycation end product receptor 3 (galectin 3) was also significantly reduced. Conclusion Concomitant inhibition of RAS and RAGE signalling almost completely inhibited the development of experimental DAA. A dual therapeutic approach may be a superior strategy for the treatment of diabetic macrovascular disease. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
32. Transforming growth factor-β1-mediated renal fibrosis is dependent on the regulation of transforming growth factor receptor 1 expression by let-7b.
- Author
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Wang, Bo, Jha, Jay C, Hagiwara, Shinji, McClelland, Aaron D, Jandeleit-Dahm, Karin, Thomas, Merlin C, Cooper, Mark E, and Kantharidis, Phillip
- Abstract
Renal fibrosis results from excessive accumulation of extracellular matrix mainly driven by transforming growth factor-β1 (TGF-β1). Certain microRNAs have been implicated in this disease, and here we examine the role of let-7b. Rat proximal tubular epithelial cells (NRK52E) were treated with TGF-β1 for 3 days to assess the expression of markers of fibrosis and let-7b. These factors were also assessed in two mouse models representing early and more advanced diabetic nephropathy and in the non-diabetic adenine-induced renal fibrosis model. TGF-β1 downregulated the expression of let-7b and induced fibrogenesis in NRK52E cells. Ectopic expression of let-7b repressed TGF-β1 receptor 1 (TGFBR1) expression directly by targeting the two let-7b binding sites in the 3'-untranslated region of that gene, reduced expression of extracellular matrix proteins, decreased SMAD3 activity, and attenuated the profibrotic effects of TGF-β1. Knockdown of let-7b elevated TGFBR1 expression and mimicked some of the profibrotic effects of TGF-β1. Consistent with these observations, let-7b expression was also reduced in models of both diabetic and non-diabetic renal fibrosis with the upregulation of TGFBR1. Thus, let-7b microRNA represents a potential new target for the treatment of renal fibrosis in diabetic and non-diabetic nephropathy. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
33. Urban wastewater treatment plants as hotspots for the release of antibiotics in the environment: A review
- Author
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Michael, I., Rizzo, L., McArdell, C.S., Manaia, C.M., Merlin, C., Schwartz, T., Dagot, C., and Fatta-Kassinos, D.
- Subjects
- *
SEWAGE disposal plants , *HOT spots (Pollution) , *ANTIBIOTICS , *ACTIVATED carbon , *ADSORPTION (Chemistry) , *TOXICOLOGY of water pollution , *ARTIFICIAL membranes - Abstract
Abstract: Urban wastewater treatment plants (UWTPs) are among the main sources of antibiotics'' release into various compartments of the environment worldwide. The aim of the present paper is to critically review the fate and removal of various antibiotics in wastewater treatment, focusing on different processes (i.e. biological processes, advanced treatment technologies and disinfection) in view of the current concerns related to the induction of toxic effects in aquatic and terrestrial organisms, and the occurrence of antibiotics that may promote the selection of antibiotic resistance genes and bacteria, as reported in the literature. Where available, estimations of the removal of antibiotics are provided along with the main treatment steps. The removal efficiency during wastewater treatment processes varies and is mainly dependent on a combination of antibiotics'' physicochemical properties and the operating conditions of the treatment systems. As a result, the application of alternative techniques including membrane processes, activated carbon adsorption, advanced oxidation processes (AOPs), and combinations of them, which may lead to higher removals, may be necessary before the final disposal of the effluents or their reuse for irrigation or groundwater recharge. [Copyright &y& Elsevier]
- Published
- 2013
- Full Text
- View/download PDF
34. Osteoprotegerin promotes vascular fibrosis via a TGF-β1 autocrine loop
- Author
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Toffoli, Barbara, Pickering, Raelene J., Tsorotes, Despina, Wang, Bo, Bernardi, Stella, Kantharidis, Phillip, Fabris, Bruno, Zauli, Giorgio, Secchiero, Paola, and Thomas, Merlin C.
- Subjects
- *
TUMOR necrosis factors , *FIBROSIS , *TRANSFORMING growth factors-beta , *AUTOCRINE mechanisms , *ATHEROSCLEROSIS , *SMOOTH muscle , *CYTOKINES - Abstract
Abstract: Background: This study was designed to evaluate the potential role of osteoprotegerin (OPG) in arterial fibrosis. Methods: Aortic samples were analyzed after in vivo treatment of ApoE−/− mice with recombinant human OPG. Mouse vascular smooth muscle cells (VSMC) were exposed in vitro to recombinant OPG and analyzed for markers of inflammation and fibrosis, such as fibronectin, collagen I, III, IV and transforming growth factor-β1 (TGF-β1). Conversely, the potential modulation of endogenous OPG expression and release by VSMC was analyzed in response to different pro-atherosclerotic cytokines, TGF-β1, platelet derived growth factor (PDGF) and angiogensin II (Ang II). Results: In vivo treatment with human OPG induced signs of fibrosis and up-regulated the arterial expression of TGF-β1. Consistently, in vitro treatment of VSMC with human OPG induced the expression of fibronectin, collagen type I, III, IV, metalloprotein-2 (MMP-2) and MMP-9, as well as of TGF-β1. On the other hand, exposure to recombinant TGF-β1 promoted the expression/release of endogenous OPG and mediated the increase of OPG release induced by PDGF and Ang II in VSMC. Conclusions: Taken together, these data support a pathogenic role for OPG in the development and progression of atherosclerotic lesions and suggest the existence of a vicious circle between TGF-β1 and OPG. [Copyright &y& Elsevier]
- Published
- 2011
- Full Text
- View/download PDF
35. Targeted reduction of advanced glycation improves renal function in obesity.
- Author
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Harcourt, Brooke E., Sourris, Karly C., Coughlan, Melinda T., Walker, Karen Z., Dougherty, Sonia L., Andrikopoulos, Sofianos, Morley, Amy L., Bonke, Vicki Thallas, Chand, Vibhasha, Penfold, Sally A., de Courten, Maximilian P. J., Thomas, Merlin C., Kingwell, Bronwyn A., Bierhaus, Angelika, Cooper, Mark E., de Courten, Barbora, and Forbes, Josephine M.
- Subjects
- *
OBESITY , *KIDNEY diseases , *BODY mass index , *INFLAMMATION , *MONOCYTES - Abstract
Obesity is highly prevalent in Western populations and is considered a risk factor for the development of renal impairment. Interventions that reduce the tissue burden of advanced glycation end-products (AGEs) have shown promise in stemming the progression of chronic disease. Here we tested if treatments that lower tissue AGE burden in patients and mice would improve obesity-related renal dysfunction. Overweight and obese individuals (body mass index (BMI) 26-39 kg/m2) were recruited to a randomized, crossover clinical trial involving 2 weeks each on a low- and a high-AGE-containing diet. Renal function and an inflammatory profile (monocyte chemoattractant protein-1 (MCP-1) and macrophage migration inhibitory factor (MIF)) were improved following the low-AGE diet. Mechanisms of advanced glycation-related renal damage were investigated in a mouse model of obesity using the AGE-lowering pharmaceutical, alagebrium, and mice in which the receptor for AGE (RAGE) was deleted. Obesity, resulting from a diet high in both fat and AGE, caused renal impairment; however, treatment of the RAGE knockout mice with alagebrium improved urinary albumin excretion, creatinine clearance, the inflammatory profile, and renal oxidative stress. Alagebrium treatment, however, resulted in decreased weight gain and improved glycemic control compared with wild-type mice on a high-fat Western diet. Thus, targeted reduction of the advanced glycation pathway improved renal function in obesity. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
36. Circulating high-molecular-weight RAGE ligands activate pathways implicated in the development of diabetic nephropathy.
- Author
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Penfold, Sally A., Coughlan, Melinda T., Patel, Sheila K., Srivastava, Piyush M., Sourris, Karly C., Steer, David, Webster, Diane E., Thomas, Merlin C., MacIsaac, Richard J., Jerums, George, Burrell, Louise M., Cooper, Mark E., and Forbes, Josephine M.
- Subjects
- *
DIABETIC nephropathies , *DIABETES complications , *TYPE 2 diabetes , *SERUM , *KIDNEY diseases - Abstract
The accumulation of advanced glycation end products is thought to be a key factor in the initiation and progression of diabetic nephropathy. Here we determined whether the size of the ligands for the receptor for advanced glycation end products (RAGEs) that were present in the serum of patients with type 2 diabetes modulates their pathogenic potential. Serum was collected from control subjects and patients with type 2 diabetes with varying degrees of renal disease (normo-, micro-, or macroalbuminuria). The titers of the RAGE ligands N-carboxymethyllysine (CML), S100A, S100B, and high-mobility group box 1 (HMGB1) were measured by enzyme-linked immunosorbent assay in serum as well as in pooled size-fractionated serum. We also measured cellular binding of serum fractions to mesangial cells transfected with RAGE and examined the downstream signaling pathways. Circulating CML was increased in patients with type 2 diabetes, whereas HMGB1 was decreased. S100A8, S100BA9, and soluble RAGE were unchanged. The high-molecular-weight (over 50 kDa) serum fraction contained the greatest proportion of RAGE ligands, with all immunoreactivity and cellular binding observed only with serum fractions over 30 kDa. High-molecular-weight serum from macroalbuminuric patients showed greater RAGE binding capacity, modulation of cell-surface RAGE expression, increased phospho-protein kinase C-α, and p65 nuclear factor κB DNA-binding activity, which were competitively inhibited by soluble RAGE or CML neutralizing antibodies. These data show that ligands that activate RAGE present in the circulation of patients with type 2 diabetes and nephropathy are predominantly of high molecular weight. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
37. Increased atherosclerosis following treatment with a dual PPAR agonist in the ApoE knockout mouse
- Author
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Calkin, Anna C., Allen, Terri J., Lassila, Markus, Tikellis, Christos, Jandeleit-Dahm, Karin A., and Thomas, Merlin C.
- Subjects
- *
APOLIPOPROTEIN E , *CELL adhesion , *CELL communication , *ISOPENTENOIDS - Abstract
Abstract: Objective: Recent reports have suggested that dual peroxisome proliferator-activated receptor (PPAR) α/γ agonists are associated with adverse cardiovascular events. This study aimed to investigate the actions of the non-thiazolidinedione PPARα/γ agonist, compound 3q, on plaque development in the apolipoprotein E knockout (apoE KO) mouse, a recognised model of accelerated plaque development. Methods: Six-week-old male apoE KO mice were randomised to receive the dual PPARα/γ agonist, compound 3q (3mg/kg/day), the PPARγ agonist, rosiglitazone (20mg/kg/day), the PPARα agonist, gemfibrozil (100mg/kg/day) by gavage or no treatment for 20 weeks (n =12/group). Results: Gemfibrozil and rosiglitazone significantly reduced lesion area. However, compound 3q was associated with a three-fold increase in total plaque area (versus control p <0.001). This was associated with an upregulation of markers of plaque instability including vascular cell adhesion molecule-1 (3.5-fold, p <0.001), P-selectin (3.4-fold, p <0.001) monocyte chemoattractant protein-1 (3.4-fold; p <0.001) as well as the scavenger receptor, CD36 (2-fold, p <0.01). These disparate effects were observed with the dual PPAR agonist despite lowering LDL cholesterol and improving insulin sensitivity to a similar extent to PPARα and γ agonists used individually. Conclusion: The finding of increased atherogenesis following a dual PPARα/γ agonist is consistent with recent clinical findings. These data provide an important framework for further exploring the potential utility and safety of combinatorial approaches. [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
- View/download PDF
38. Baseline Patient Characteristics of A Prospective Observational Study to Evaluate the Care Map of Women With Postmenopausal Osteoporosis (Pmo) in Switzerland (Campos).
- Author
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Lippuner, K., Lamy, O., Theiler, R., Merlin, C., Pendl, G., Del, Ponte A., Murigande, C., and Schwenkglenks, M.
- Subjects
- *
OSTEOPOROSIS in women , *RHEUMATOLOGY , *SCIENTIFIC observation , *LONGITUDINAL method , *DIAGNOSIS , *THERAPEUTICS - Published
- 2014
- Full Text
- View/download PDF
39. Efficacité de l’adalimumab dans la maladie de Takayasu : à propos d’un cas
- Author
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Baudenon, J., Guettrot-Imbert, G., Andre, M., Merlin, C., Delarbre, X., Delèvaux, I., and Aumaitre, O.
- Published
- 2011
- Full Text
- View/download PDF
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