Effect of molecular structure of aniline-formaldehyde copolymers on corrosion inhibition of mild steel in hydrochloric acid solution.

Aniline-formaldehyde copolymers with different molecular structures have been prepared and investigated for the purpose of corrosion control of mild steel in hydrochloric acid. The copolymers were synthesized by a condensation polymerization process with different ratios of aniline to formaldehyde in acidic precursor solutions. The corrosion inhibition efficiency of as-synthesized copolymers for Q235 mild steel was investigated in 1.0 mol L(-1) hydrochloric acid solution by weight loss measurement, potentiodynamic polarization, and electrochemical impedance spectroscopy, respectively. All the results demonstrate that as-prepared aniline-formaldehyde copolymers are efficient mixed-type corrosion inhibitors for mild steels in hydrochloric acid. The corrosion inhibition mechanism is discussed in terms of the role of molecular structure on adsorption of the copolymers onto the steel surface in acid solution.

Serum miR-499 as a novel diagnostic and prognostic biomarker in non-small cell lung cancer.

The aim of the present study was to determine whether serum miR-499 may be used as a biomarker for early detection of non-small cell lung cancer (NSCLC). The present study was designed as an initial screening phase and a subsequent validation phase. In the screening phase, we analyzed serum levels of miR-499 in a subset of 40 patients with stage I (n=20) and stage IV (n=20) NSCLC. In the validation phase, miR-499 expression levels in serum (n=514) and tissue (n=136) from NSCLC patients were detected in a large and independent cohort of 514 patients. miR-499 in the screening phase was found to be significantly elevated in the serum of stage I NSCLC patients compared with that in stage IV NSCLC patients (P<0.001). Validation analysis showed that serum miR-499 levels were robust in differentiating NSCLC patients from control subjects [area under the curve (AUC)=0.906; 95% confidence interval (CI)=0.879 to 0.929). Serum miR-499 levels were significantly lower in stage III and IV patients compared with those with stage I (both P<0.001) or II (both P<0.001). Low serum miR-499 levels were associated with shorter overall survival and served as an independent prognostic biomarker in NSCLC patients [hazard ratio (HR)=1.63; 95% CI=1.33-2.0; P<0.0001). In addition, low serum levels of miR-499 indicated a poor disease-free survival in stage I-II NSCLC patients. Serum miR-499 may prove to be a promising biomarker for early detection and prognosis prediction of NSCLC.