Screening of deafness-causing DNA variants that are common in patients of European ancestry using a microarray-based approach

The unparalleled heterogeneity in genetic causes of hearing loss along with remarkable differences in prevalence of causative variants among ethnic groups makes single gene tests technically inefficient. Although hundreds of genes have been reported to be associated with nonsyndromic hearing loss (NSHL), GJB2, GJB6, SLC26A4, and mitochondrial (mt) MT-RNR1 and MTTS are the major contributors. In order to provide a faster, more comprehensive and cost effective assay, we constructed a DNA fluidic array, CapitalBioMiamiOtoArray, for the detection of sequence variants in five genes that are common in most populations of European descent. They consist of c.35delG, p.W44C, p.L90P, c.167delT (GJB2); 309kb deletion (GJB6); p.L236P, p.T416P (SLC26A4); and m.1555A>G, m.7444G>A (mtDNA). We have validated our hearing loss array by analyzing a total of 160 DNAs samples. Our results show 100% concordance between the fluidic array biochip-based approach and the established Sanger sequencing method, thus proving its robustness and reliability at a relatively low cost

A polyphenol‐induced hydroxyapatite coating modulates corrosion resistance and biocompatibility of magnesium alloys

Abstract In order to solve the problem of excessive degradation rate and insufficient biocompatibility of magnesium‐based bone implants, a polyphenol (EGCG) induced hydroxyapatite (HA) coating was prepared on the surface of AZ31 alloy. The physical and chemical properties and corrosion resistance of the coating were analysed in depth, and its biocompatibility was preliminarily explored in vitro. The results showed that the polyphenol (EGCG) conversion coating constructed on the AZ31 could successfully induce the formation of HA by complexing the phenolic hydroxyl group with calcium ions. The electrochemical and long‐term immersion experiments showed that the corrosion resistance of EGCG/HA composite coating was significantly improved. The self‐corrosion current density, hydrogen evolution and the increase of pH value of AZ31‐EGCG/HA were significantly lower than those of AZ31. On the basis of inhibiting the excessive corrosion of the substrate, the composite coating significantly improves the compatibility of pre‐osteoblasts, supports the adhesion and spreading and effectively reduces the haemolysis rate to less than 5%. The preparation method of the coating is simple, low cost and suitable for complex shape surfaces, which can significantly improve the corrosion resistance and biocompatibility of the AZ31 substrate. It is expected to provide a solution for the surface modification of magnesium‐based bone implants

The principle for design of the amplification primers.

<p>Multiplex PCR is performed as described previously [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0169219#pone.0169219.ref027" target="_blank">27</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0169219#pone.0169219.ref028" target="_blank">28</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0169219#pone.0169219.ref029" target="_blank">29</a>]. Asymmetric PCR procedure was used for generation of labeled single-stranded DNA in excess for hybridization and detection.</p

Mutations detected in the deaf individuals.

<p>Mutations detected in the deaf individuals.</p

Microarray design.

<p>(A) Copy of the microarray; (B) the microarray layout. QC: chemical control; PC: external control; BC: blank control; NC: negative control; IC: internal control; MC: magnetic control; W: wild-type; M: mutant.</p