Publications by authors named "Joles J"

Accurate assessment of the glomerular filtration rate (GFR) is crucial for researching kidney disease in rats. Although validation of methods that assess GFR is crucial, large-scale comparisons between different methods are lacking. Both transcutaneous GFR (tGFR) and a newly developed estimated GFR (eGFR) equation by our group provide a low-invasive approach enabling repeated measurements.

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Heart failure with preserved ejection fraction (HFpEF) is characterized by obesity, hypertension, diabetes mellitus, and chronic kidney disease. Obese ZSF1 rats, a model of HFpEF, exhibit multiple such comorbidities that can disturb cardiac function. Little attention has been paid to how these comorbidities affect renal disease in ZSF1 rats.

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With increasing interest in home dialysis, there is a need for a translational uremic large animal model to evaluate technical innovations in peritoneal dialysis (PD). To this end, we developed a porcine model with kidney failure. Stable chronic kidney injury was induced by bilateral subtotal renal artery embolization.

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Albumin is the most abundant protein in blood plasma and acts as a carrier for many circulating molecules. Hypoalbuminaemia, mostly caused by either renal or liver disease or malnutrition, can perturb vascular homeostasis and is involved in the development of multiple diseases. Here we review four functions of albumin and the consequences of hypoalbuminaemia on vascular homeostasis.

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Background And Objectives: Sodium-glucose transporter 2 (SGLT2) inhibitor-induced uric acid lowering may contribute to kidney-protective effects of the drug class in people with type 2 diabetes. This study investigates mechanisms of plasma uric acid lowering by SGLT2 inhibitors in people with type 2 diabetes with a focus on urate transporter 1.

Design, Setting, Participants, & Measurements: We conducted an analysis of two randomized clinical trials.

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Objective: Kidney insulin clearance, proposed to be the main route of extra-hepatic insulin clearance, occurs in tubular cells following glomerular filtration and peritubular uptake, a process that may be impaired in people with type 2 diabetes (T2D) and/or impaired kidney function. Human studies that investigated kidney insulin clearance are limited by the invasive nature of the measurement. Instead, we evaluated relationships between whole-body insulin clearance, and gold-standard measured kidney function and insulin sensitivity in adults with T2D and normal kidney function.

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Aims: Glomerular hyperfiltration plays a key role in the pathophysiology of diabetic kidney disease (DKD). Mechanisms underlying this adverse hemodynamic profile are incompletely understood. We hypothesized that systemic vascular pathology, including endothelial dysfunction and arterial stiffness, relates to glomerular hyperfiltration indicated by filtration fraction (FF).

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Background: Acquiring a reliable estimate of glomerular filtration rate (eGFR) at the emergency department (ED) is important for clinical management and for dosing renally excreted drugs. However, renal function formulas such as CKD-EPI can give biased results when serum creatinine (SCr) is not in steady-state because the assumption that urinary creatinine excretion is constant is then invalid. We assessed the extent of this by analysing variability in SCr in patients who visited the ED of a tertiary care centre.

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Aim: To determine the effect of the dipeptidyl peptidase-4 inhibitor linagliptin on postprandial glomerular hyperfiltration compared with the sulphonylurea glimepiride in adults with type 2 diabetes (T2D).

Materials And Methods: In this predefined substudy within a randomized, double-blind, parallel-group, intervention trial, overweight people with T2D without renal impairment were treated with once-daily linagliptin 5 mg (N = 10) or glimepiride 1 mg (N = 13) as an add-on to metformin for 8 weeks. After a standardized liquid protein-rich meal, the glomerular filtration rate (GFR) and effective renal plasma flow were determined by inulin and para-aminohippuric acid clearance, respectively, based on timed urine sampling.

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In the present study, we tested the hypothesis that multiple risk factors, including diabetes mellitus (DM), dyslipidaemia and chronic kidney disease (CKD) result in a loss of nitric oxide (NO) signalling, thereby contributing to coronary microvascular dysfunction. Risk factors were induced in 12 female swine by intravenous streptozotocin injections (DM), a high fat diet (HFD) and renal artery embolization (CKD). Female healthy swine (n = 13) on normal diet served as controls (Normal).

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The kidney is among the most complex organs in terms of the variety of cell types. The cellular complexity of human kidneys is not fully unraveled and this challenge is further complicated by the existence of multiple progenitor pools and differentiation pathways. Researchers disagree on the variety of renal cell types due to a lack of research providing a comprehensive picture and the challenge to translate findings between species.

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A major challenge for the development of a wearable artificial kidney (WAK) is the removal of urea from the spent dialysate, as urea is the waste solute with the highest daily molar production and is difficult to adsorb. Here we present results on glucose degradation products (GDPs) formed during electrooxidation (EO), a technique that applies a current to the dialysate to convert urea into nitrogen, carbon dioxide, and hydrogen gas. Uremic plasma and peritoneal effluent were dialyzed for 8 hours with a WAK with and without EO-based dialysate regeneration.

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Kidney transplant recipients (KTR) may be at increased risk of adverse COVID-19 outcomes, due to prevalent comorbidities and immunosuppressed status. Given the global differences in COVID-19 policies and treatments, a robust assessment of all evidence is necessary to evaluate the clinical course of COVID-19 in KTR. Studies on mortality and acute kidney injury (AKI) in KTR in the World Health Organization COVID-19 database were systematically reviewed.

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Cardiorenal syndrome type 2 is characterized by kidney failure as a consequence of heart failure that affects >50% of heart failure patients. Murine transverse aortic constriction (TAC) is a heart failure model, where pressure overload is induced on the heart without any systemic hypertension or its consequences. Whether renal function is altered in this model is debated, and if so, at which time post-TAC renal dysfunction starts to contribute to worsening of cardiac function.

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The preclinical evaluation of novel therapies for chronic kidney disease requires a simple method for the assessment of kidney function in a uremic large animal model. An intravenous bolus of iohexol was administered to goats (13 measurements in = 3 goats) and pigs (23 measurements in = 5 pigs) before and after induction of kidney failure, followed by frequent blood sampling up to 1440 min. Plasma clearance (CL) was estimated by a nonlinear mixed-effects model (CL) and by a one-compartmental pharmacokinetic disposition model using iohexol plasma concentrations during the terminal elimination phase (CL).

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Glucagon-like peptide 1 receptor agonists have shown cardioprotective effects which have been suggested to be mediated through inhibition of oxidative stress. We investigated the effect of treatment with a glucagon-like peptide 1 receptor agonist (liraglutide) on oxidative stress measured as urinary nucleic acid oxidation in persons with type 2 diabetes. Post-hoc analysis of two independent, randomised, placebo-controlled and double-blinded clinical trials.

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Hypertension contributes to cardiac damage and remodeling. Despite the availability of renin-angiotensin system inhibitors and other antihypertensive therapies, some patients still develop heart failure. Novel therapeutic approaches are required that are effective and without major adverse effects.

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A large animal model of (end-stage) kidney disease (ESKD) is needed for the preclinical testing of novel renal replacement therapies. This study aimed to create stable uremia via subtotal renal artery embolization in goats and induce a temporary further decline in kidney function by administration of gentamicin. Renal artery embolization was performed in five Dutch white goats by infusing polyvinyl alcohol particles in branches of the renal artery, aiming for the embolization of ~80% of one kidney and complete embolization of the contralateral kidney.

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The progression of kidney disease may differ between sexes in type 2 diabetes (T2D), with previous studies reporting a slower decline in women. Glomerular hyperfiltration is a key factor driving the kidney function decline. The current study aimed to investigate the differences in kidney hemodynamic function between men and women with T2D.

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Objective: Diabetic kidney disease is a microvascular complication of diabetes. Here, we assessed the association between skin microvascular function and renal hemodynamic function in a cohort of well-phenotyped adults with type 2 diabetes (T2D).

Methods: We included 81 overweight/obese adults (age: 62 ± 8 years; BMI: 32 ± 4 kg/m ) with well-controlled T2D and no renal impairment.

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Hydrogen sulfide (HS) is an essential gaseous signaling molecule. Research on its role in physiological and pathophysiological processes has greatly expanded. Endogenous enzymatic production through the transsulfuration and cysteine catabolism pathways can occur in the kidneys and blood vessels.

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