ABSTRACT
Rutin,a flavonoid found in fruits and vegetables,is a potential anticancer compound with strong anti-cancer activity.Therefore,electrochemical sensor was developed for the detection of rutin.In this study,CoWO4 nanosheets were synthesized via a hydrothermal method,and porous carbon(PC)was prepared via high-temperature pyrolysis.Successful preparation of the materials was confirmed,and character-ization was performed by transmission electron microscopy,scanning electron microscopy,and X-ray photoelectron spectroscopy.A mixture of PC and CoWO4 nanosheets was used as an electrode modifier to fabricate the electrochemical sensor for the electrochemical determination of rutin.The 3D CoWO4 nanosheets exhibited high electrocatalytic activity and good stability.PC has a high surface-to-volume ratio and superior conductivity.Moreover,the hydrophobicity of PC allows large amounts of rutin to be adsorbed,thereby increasing the concentration of rutin at the electrode surface.Owing to the syn-ergistic effect of the 3D CoWO4 nanosheets and PC,the developed electrochemical sensor was employed to quantitively determine rutin with high stability and sensitivity.The sensor showed a good linear range(5-5000 ng/mL)with a detection limit of O.45 ng/mL.The developed sensor was successfully applied to the determination of rutin in crushed tablets and human serum samples.
ABSTRACT
Atrial fibrillation (AF) is the most frequently diagnosed cardiac arrhythmia worldwide. Patients with permanent atrialfibrillation are at an increased risk of developing valvular heart disease. Atrial fibrosis occurs in this pathophysiologicalsetting. LIM kinase 1 (LIMK1) is a serine/threonine kinase that regulates microtubule stability and actin polymerization infibroblasts. LIMK1 has been implicated in the pathogenesis of atrial fibrillation. Clinical data and biopsies of the right atrialappendage were collected from 50 patients with valvular heart disease who underwent heart valve replacement surgery.Data from patients with permanent atrial fibrillation (AF) and patients with sinus rhythm (SR) were compared. We foundthat AF patients had upregulated expression of LIMK1 as well as higher fibrosis. Transforming growth factor-b (TGF-b)stimulation induced the differentiation of cardiac fibroblasts into myofibroblasts as well as upregulated expression ofLIMK1. Downregulation of LIMK1 by siRNA inhibited TGF-b induced fibroblast-myofibroblast transition, as evidencedby the downregulation of the expression of several differentiation markers, namely alpha-smooth muscle actin and type Iand III collagen. Our findings revealed that increased LIMK1 protein levels may contribute to atrial fibrosis, and suggestedthat LIMK1 might be involved in AF development by promoting fibrogenesis associated with TGF-b.