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A sensitive amperometric glucose biosensor based on platinum nanoparticles (PtNPs) combined aligned carbon nanotubes (ACNTs) electrode was investigated. PtNPs which can enhance the electrocatalytic activity of the electrode for electrooxidating hydrogen peroxide by enzymatic reaction were electrocrystallized on 4-aminobenzene monolayer-grafted ACNTs electrode by potential-step method. These PtNPs combined ACNTs (PtNPs/ACNTs) surfaces were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The highly dispersed PtNPs on ACNTs can be obtained. The enzyme electrode exhibits excellent response performance to glucose with linear range from 1 Â 10 À5 -7 Â 10 À3 mol L À1 and fast response time within 5 s. Furthermore, this glucose biosensor also has good reproducibility. It is demonstrated that the PtNPs/ACNTs electrode with high electrocatalytic activity is a suitable basic electrode for preparing enzyme electrodes.

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Aligned carbon nanotubes (ACNTs) were modified with polypyrrole (PPy) via electropolymerization. Because of the large specific surface area and excellent electrical conductivity of ACNTs, continuous electropolymerization was able to be carried out, forming a thick PPy coating on the ACNTs. The resulting nanocomposite possessed a core-shell structure with ACNTs as the core, PPy as the shell, and nanoparticles of PPy on the top, and displayed high performance supercapacitance properties.

To identify potential predictors by assessing adverse outcomes in ANCA-associated vasculitis (AAV) patients. Eighty-nine untreated AAV patients were followed up to January 31, 2022, death, or loss of follow-up. Clinical characteristics, laboratory tests, treatment, and progress were collected, and disease activity was evaluated via Birmingham Vasculitis Activity Score (BVAS). We determined risk factors of high-risk events, defined as developing tumors, renal replacement therapy (RRT), and death. Patients and renal survivals were computed by the Kaplan–Meier curve analysis. Cox regression analysis was performed for assessing variables for predicting death. During 267 person-years follow-up, 46 patients occurred high-risk events, including 20 patients receiving RRT, 12 patients developing tumors, and 29 patients who died mostly from organ failure and infection. Decreased estimated glomerular filtration rate (eGFR) (P < 0.001) and complement 3 levels (P = 0.019) were associated with high-risk events. Patients with lower serum potassium tended to develop tumors (P = 0.033); with higher BVAS (HR = 1.290, 95%CI 1.075–1.549, P = 0.006) and lower eGFR (HR = 0.782, 95%CI 0.680–0.901, P = 0.001) were more likely to undergo RRT. Patients with cardio and renal involvement exhibited a lower frequency of renal survival and all-cause mortality. Through multivariate COX analysis, age (HR = 1.016, 95%CI 1.016–1.105, P = 0.006) and eGFR (HR = 0.982, 95%CI 0.968–0.997, P = 0.018) predicted death in AAV, separately. The BVAS and eGFR could be a great prognosticator for RRT, while age and eGFR can independently predict the death. Serum potassium level and immunoglobulins should be focused on their predictor value in development of cancer and renal outcomes in AAV patients.