Variants of the promoter of MYH6 gene in congenital isolated and sporadic patent ductus arteriosus: case-control study and cellular functional analyses

Patent ductus arteriosus (PDA) is a common form of congenital heart disease. The MYH6 gene has important effects on cardiovascular growth and development, but the effect of variants in the MYH6 gene promoter on ductus arteriosus is unknown. DNA was extracted from blood samples of 721 subjects (428 patients with isolated and sporadic PDA and 293 healthy controls) and analyzed by sequencing for MYH6 gene promoter region variants. Cellular function experiments with three cell lines (HEK-293, HL-1, and H9C2 cells) and bioinformatics analyses were performed to verify their effects on gene expression. In the MYH6 gene promoter, 11 variants were identified. Four variants were found only in patients with PDA and 2 of them (g.3434G>C and g.4524C>T) were novel. Electrophoretic mobility shift assay showed that the transcription factors bound by the promoter variants were significantly altered in comparison to the wild-type in all three cell lines. Dual luciferase reporter showed that all the 4 variants reduced the transcriptional activity of the MYH6 gene promoter (P < 0.05). Prediction of transcription factors bound by the variants indicated that these variants alter the transcription factor binding sites. These pathological alterations most likely affect the contraction of the smooth muscle of ductus arteriosus, leading to PDA. This study is the first to focus on variants at the promoter region of the MYH6 gene in PDA patients with cellular function tests. Therefore, this study provides new insights to understand the genetic basis and facilitates further studies on the mechanism of PDA formation.

Preparation of novel Fe-containing zeolite-A for KN-R decolorization by Fenton-like reaction

Herein, novel catalysts of Fe-containing zeolite-A (Fe/zeolite-A) were synthesized by exchanging iron ions into zeolite-A framework, and short-chain organic acids (SCOAs) were employed as chelating agents. Reactive Brilliant Blue KN-R (KN-R) was used as a model pollutant to evaluate the performance of these catalysts based on the heterogeneous Fenton reaction. The results showed that Fe-OA/3A, which applied zeolite-3A as the supporter and oxalic as the chelating agent, presented the most prominent KN-R decolorization efficiency. Under the initial pH of 2.5, 0.4 mM KN-R could be totally decolorized within 20 min. However, the mineralization efficiency of KN-R was only 58.2%. Therefore, anthraquinone dyes were introduced to modify zeolite-3A. As a result, the mineralization efficiency of KN-R was elevated to 92.7% when using Alizarin Violet (AV) as the modifier. Moreover, the modified catalysts exhibited excellent stability, the KN-R decolorization efficiency could be maintained above 95.0% within 20 min after operating for nine cycles. The mechanism revealed that the Fe(II)/Fe(III) cycle was accelerated by AV-modified catalyst thus prompting the KN-R decolorization in Fenton-like system. These findings provide new insights for preparing catalysts with excellent activity and stability for dye wastewater treatment.