The complete chloroplast genome sequence of the North American sclerophyllous evergreen shrub, <i>Quercus turbinella</i> (Fagaceae)

Quercus turbinella (section Quercus; Fagaceae) is an evergreen shrub characteristic in central Arizona and it concerns one of the most abundant and economically important genera of Quercus in the Northern Hemisphere. Here, we have sequenced the complete chloroplast genome to provide insight into the phylogenetic relationship of Q. turbinella. The whole genome is 161,208 bp in length with two inverted repeat regions of 25,827 bp each, which separate a large single-copy region of 90,552 bp and a small single-copy region of 19,002 bp. A total of 136 genes were annotated, including 88 protein-coding genes, eight ribosomal RNAs, and 40 transfer RNAs. The result of the maximum-likelihood phylogenetic analysis strongly suggested that Quercus turbinella had a close relationship to Quercus macrocarpa with strong bootstrap support.</p

Layer-by-Layer Assembly of Graphene Oxide Nanosheets on Polyamide Membranes for Durable Reverse-Osmosis Applications

Improving membrane durability associated with fouling and chlorine resistance remains one of the major challenges in desalination membrane technology. Here, we demonstrate that attractive features of graphene oxide (GO) nanosheets such as high hydrophilicity, chemical robustness, and ultrafast water permeation can be harnessed for a dual-action barrier coating layer that enhances resistance to both fouling and chlorine-induced degradation of polyamide (PA) thin-film composite (TFC) membranes while preserving their separation performance. GO multilayers were coated on the PA-TFC membrane surfaces via layer-by-layer (LbL) deposition of oppositely charged GO nanosheets. Consequently, it was shown that the conformal GO coating layer can increase the surface hydrophilicity and reduce the surface roughness, leading to the significantly improved antifouling performance against a protein foulant. It was also demonstrated that the chemically inert nature of GO nanosheets enables the GO coating layer to act as a chlorine barrier for the underlying PA membrane, resulting in a profound suppression of the membrane degradation in salt rejection upon chlorine exposure

Effect of Final Monomer Deposition Steps on Molecular Layer-by-Layer Polyamide Surface Properties

A current challenge to desalination membrane technology is the inability to precisely control the properties of the polyamide selective layer due to the complexity of interfacial polymerization. In this study, we investigate the ability of molecular layer-by-layer (mLbL) assembly, an alternative polyamide fabrication technique, to create polyamide surfaces with tunable chemistry. We explore the influence of terminating monomer, monomer deposition time, monomer size, and the presence of underlying ionizable functional groups on mLbL-derived polyamide surface properties. AFM colloidal probe measurements, contact angle titrations, QCM cesium adsorption experiments, and XPS data show that polyamide films terminated with <i>m-</i>phenylenediamine or trimesoyl chloride for 20–30 s are chemically similar. Increasing terminating monomer deposition time or using a smaller, more reactive monomer results in more distinct colloidal-probe adhesive interactions, contact angle titration curves, negative charge densities, and near surface atomic compositions. By optimizing the final monomer deposition steps, both amine-rich and carboxyl-rich polyamide surfaces can be fabricated, which has implications for the application of mLbL assembly to membrane-based desalination

Tailoring the Permselectivity of Water Desalination Membranes via Nanoparticle Assembly

Thin film composite membranes can selectively separate mono- and divalent ions from water via solution-diffusion of each species through a dense but ultrathin, highly cross-linked polymer “skin” layer; water is transported across the membrane faster than associated salts. Changing the selectivity of the “skin” layer typically requires adjusting the monomer chemistries that make up the polymer “skin” layer, but doing so also impacts a host of other membrane properties. Here, we employ electrostatic layer-by-layer deposition of inorganic nanoparticles to enhance the permselectivity of an existing commercial nanofiltration membrane. We chose this approach because it is simple and robust and does not require any change to the underlying chemistry of the thin film composite (TFC) membrane. We found that a single layer of nanoparticles was sufficient to increase the permselectivity of the membrane by nearly 50%, compared to the virgin TFC membrane. In order to understand the mechanism for permselectivity enhancement, we developed a modified solution-diffusion model to account for the additional hydraulic resistance of the nanoparticle layer, which can faithfully capture the effect of nanoparticle layer thickness on the observed water and salt flux of the modified TFC membrane

Knockdown of Sox10 leads to inhibition of migration of B16F10 melanoma cells.

<p>B16F10 murine melanoma cells were transfected with control siRNAs, MT1-Sox10 (A, B; MT, mutant) and MT2-Sox10 (E, F) or siRNAs specific for Sox10, WT1-Sox10 (C, D; WT, wild type) and WT2-Sox10 (G, H). Nuclei were stained with DAPI (A, C, E, G) and anti-Sox10 antibody (B, D, F, H). Nucleotide sequences of MT1-Sox10 and MT2-Sox10 differ from those of WT1-Sox10 and WT2-Sox10 by 5 nucleotides respectively (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0031477#pone.0031477.s007" target="_blank">Table S1</a>). Sox10 was down-regulated only with WT siRNAs (D, H) but not with MT siRNAs (B, F). B16F10 cells treated with siRNAs were put to transwell migration assay (I–M). Transfection of WT1-Sox10 (K) and WT2-siRNA (L) led to significant reduction in migration of the cells compared to transfection of MT1-Sox10 (I) or MT2-Sox10 (J). (M) Quantitation of transwell migration assay. The effect of Sox10 knockdown on the number of cells that migrated through the filter pores is shown in percentile relative to the matching control case. Values represent the average of 5 independent trials, and error bars represent standard deviations. The asterisk (*) represents a significant difference with the <i>p</i> value of <0.05.</p

Mc1r promotes migration of melanoma cells.

<p>(A) Quantitative Real time RTPCR assays were carried out using B16F10 murine melanoma cells transfected with the universal control siRNA, MT1-Mc1r, or one of the three siRNAs specific for Mc1r, WT1-Mc1r, WT2-Mc1r, and WT3-Mc1r. The nucleotide sequence of MT1-Mc1r differs from that of WT1-Mc1r by 5 nucleotides. The expression levels of Mc1r, Ald1a, and Ctbp1 were examined. The effect of Mc1r knockdown is expressed relative to that of the universal control siRNA after normalization with GAPDH expression level. Values represent the average of three independent real-time PCR experiments each carried out in duplicates, and error bars represent standard deviations. (B–G) B16F10 cells were treated with the universal control siRNA (B), MT1-Mc1r (C), WT1-Mc1r (D), WT2-Mc1r (E), or WT3-Mc1r (F) and put to transwell migration assay. (G) Quantitation of transwell migration assay. The effect of Mc1r knockdown on the number of cells that migrated through the filter pores is shown in percentile relative to the universal control case. Values represent the average of 5 independent trials, and error bars represent standard deviations. The asterisk (*) represents a significant difference with the <i>p</i> value of <0.05.</p

Nanoscale Pillar-Enhanced Tribological Surfaces as Antifouling Membranes

We present a nonconventional membrane surface modification approach that utilizes surface topography to manipulate the tribology of foulant accumulation on water desalination membranes via imprinting of submicron titanium dioxide (TiO₂) pillar patterns onto the molecularly structured, flat membrane surface. This versatile approach overcomes the constraint of the conventional approach relying on interfacial polymerization that inevitably leads to the formation of ill-defined surface topography. Compared to the nonpatterned membranes, the patterned membranes showed significantly improved fouling resistance for both organic protein and bacterial foulants. The use of hydrophilic TiO₂ as a pattern material increases the membrane hydrophilicity, imparting improved chemical antifouling resistance to the membrane. Fouling behavior was also interpreted in terms of the topographical effect depending on the relative size of foulants to the pattern dimension. In addition, computational fluid dynamics simulation suggests that the enhanced antifouling of the patterned membrane is attributed to the enhancement in overall and local shear stress at the fluid–TiO₂ pattern interface

List of genes down-regulated by WT1-Sox10.

<p>Fold change is in comparison to MT1-Sox10 transfected cells. Microarray screening was carried out in triplicates. Genes that show down-regulation by 2.5 fold or higher in all triplicates are listed. Oculospanin (oscp) is a synonym for tetraspanin 10 (Tspan10).</p

Confirmation of the role of Mc1r on cell migration using an in vivo metastasis model.

<p>(A, B) Effect of Mc1r knockdown on the development of pulmonary metastatic colony was determined. B16F10 melanoma cells were treated with MT1-Mc1r (A) or WT1-Mc1r (B) and injected into tail vein of C57BL/6 mice. Representative lungs harvested after 18 days are shown. (C) B16F10 colonies visible on the lung surface were counted and plotted. N = 9 for MT1-Mc1r and N = 8 for WT1-Mc1r. The significance of difference (p<0.0001) was determined by <i>t</i>-test.</p

Confirmation of microarray expression profiling.

<p>(A) Quantitative real time RTPCR assays were carried out using B16F10 cells transfected with the MT1-Sox10 or WT1-Sox10. A subset of genes that showed down-regulation by WT1-Sox10 in the microarray assay by 2.5 fold or higher in all triplicates (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0031477#pone-0031477-t001" target="_blank">Table 1</a>) and two non-target genes whose expression levels were unchanged (Ald1a and Ctbp1) were used to validate the results from the microarray assay. The effect of Sox10 knockdown by the specific siRNA on the expression level of each target gene is expressed relative to that of the control siRNA after normalization with GAPDH expression level. Values represent the average of three independent real-time PCR experiments each carried out in duplicates, and error bars represent standard deviations. (B) Real time RTPCR carried out with MT2-Sox10 and WT2-Sox10. The asterisk (*) represents a significant difference with the <i>p</i> value of <0.05.</p