Diagnostic value of circulating microRNA-19b in heart failure.

OBJECTIVE: For differentiating heart failure (HF) with preserved ejection fraction (HFpEF) from HF with reduced EF (HFrEF), N-terminal prohormone brain natriuretic peptide (NT-proBNP) is less accurate. Decreased expression of microRNA-19b (miR-19b) is associated with increased cardiac-fibrosis. We aim to evaluate the value of miR-19b in diagnosing HFrEF patients. METHOD: We included 200 HF patients and 100 healthy controls. Intergroup comparisons of miR-19b were made and correlation between miR-19b and NT-proBNP was analysed. Diagnostic values of NT-proBNP and miR-19b for HF patients versus controls and HFrEF versus HFpEF were obtained by ROC analysis and described by area under curve (AUC), sensitivity and specificity. RESULTS: HFrEF patients (0.87, 95% CI 0.37-1.45) had significantly lower miR-19b level than HFpEF group (1.32, 95% CI 0.63-2.51) and the controls (1.82, 95% CI 0.37-1.45) (both P < .001). There was a remarkable negative correlation between miR-19b and NT-proBNP (P < .001). The additional use of miR-19b did not improve the accuracy of NT-proBNP alone in diagnosing HF patients from the controls (both AUC = 0.98, 95%CI 0.97-0.99). However, as for distinguishing the HFpEF from HFrEF, miR-19b and NT-proBNP yielded a significantly higher AUC than NT-proBNP alone (0.85, 95% CI 0.80-0.90 vs. 0.66, 95% CI 0.58-0.74) (P < .001), and the sensitivity for diagnosing HFrEF was raised from 58% to 77% and the specificity from 75% to 79%. CONCLUSIONS: On top of NT-proBNP, miR-19b added the value in diagnosing HFrEF. But in view of satisfactory accuracy of NT-proBNP in predicting HF from the healthy volunteers, miR-19b did not provide incremental value.

Synthesis and Microwave Absorbing Properties of Porous One-Dimensional Nickel Sulfide Nanostructures.

One-dimensional (1D) porous NixSy nanostructures have been successfully fabricated by two-step method consisting of solvothermal and subsequent annealing process. The suitable heat treatment temperature and reaction time play crucial roles in the final structure, morphology, as well as performance. The uniform and perfect porous NixSy nanostructures obtained at 310°C exhibit outstanding microwave absorption performances. A minimum reflection loss of -35.6 dB is achieved at 8.5 GHz, and the effective absorption bandwidth almost covers 14.5 GHz with the absorber thickness range of 2.0-5.0 mm. It can be supposed that this porous structure with rough surface which is favor for increasing the microwave multiple reflection and scattering, contributes a high-performance electromagnetic absorption.