RESUMEN
The viscoelastic and flow properties of aqueous Laponite/TEMPO-oxidized nanofibrillated cellulose (TEMPO-NFC) systems are investigated with the aim to study the effect of content and proportion of both components on the properties. Both Laponite and TEMPO-NFC aqueous dispersions can find numerous applications in different fields (from industrial to biomedical one) due to their structural and rheological properties. The most important effects of blending are observed at low Laponite fractions, also with qualitative changes in the shape of the flow curves and mechanical spectra. Positive synergistic effects are ascribed to the interpenetration and electrostatic interactions between TEMPO-NFC fibrils and Laponite nanodisks. These mechanisms are more effective in Laponite-poor blends when a minority of clay nanoparticles and its aggregated forms are distributed within the nanocellulose matrix, acting as bridging agents between polymer nanofibrils. The synergistic effects are compared to those observed for Laponite blends with a nonionic biopolymer, scleroglucan.
Asunto(s)
Celulosa Oxidada/química , Óxidos N-Cíclicos/química , Nanofibras/química , Silicatos/química , Reología , Agua/químicaRESUMEN
Patients on haemodialysis (HD) and patients with type 2 diabetes are at high-risk for coronary artery calcification (CAC). The coronary artery calcium score (CACS), quantified by computed tomography, cannot be completely explained by traditional cardiovascular disease risk factors. CAC was measured in 45 non-diabetic chronic kidney disease patients on HD and in 45 matched type 2 diabetes patients without diabetic nephropathy. Serum calcium, phosphate, 25-hydroxyvitamin D (25[OH]D), alkaline phosphatase, intact parathyroid hormone (iPTH), fetuin-A, high-sensitivity C-reactive protein (hsCRP), albumin, homocysteine, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides and femoral neck bone mineral density were also measured. No differences were observed in patient distribution across the CACS risk categories between the two groups. Significant differences were observed in serum calcium, phosphate, 25(OH)D, alkaline phosphatase, iPTH, fetuin-A, hsCRP, homocysteine and triglycerides between the two patient groups. Further research into the diverse, numerous and often interlinked factors that influence CAC in different groups of patients is warranted.