Biodegradable and Magnetic-Fluorescent Porous Silicon@Iron Oxide Nanocomposites for Fluorescence/Magnetic Resonance Bimodal Imaging of Tumor <i>in Vivo</i>

Considering future clinical transactions, biodegradable and luminescent porous silicon nanoparticles instead of traditional heavy-metal quantum dots have an important significance on the construction of biodegradable and magnetic-fluorescent nanocomposites. Herein, to fabricate PSiNPs@Fe₃O₄ nanocomposites, superparamagnetic iron oxide nanoparticles were covalently incorporated into luminescent porous silicon nanoparticles by microwave-induced hydrosilylation. These resultant nanocomposites had near-infrared fluorescence (500 nm–800 nm) and superparamagnetism with high magnetic saturation value of 141 emu/g. The aqueous-dispersibility of PSiNPs@Fe₃O₄ nanocomposites could be significantly improved via simple ultrasonication in water. Furthermore, they also exhibited an excellent biodegradability and biocompatibility, whether <i>in vitro</i> or <i>in vivo</i>. Finally, their ability of fluorescence/magnetic resonance bimodal imaging had been successfully demonstrated for cancer cells <i>in vitro</i> or tumor tissues <i>in vivo</i>

The relationship between Δ<i>K</i> and <i>K</i>as revealed by Structure Harvester.

<p>The highest peak was at <i>K</i> = 3.</p

Bayesian model-based clustering (STRUCTURE)[60] of <i>L</i>. <i>regale</i> individuals (optimal value of <i>K</i> = 3).

<p>. YMF,2.FHB,3.SDG,4.SEG,5.XV,6.TF,7.WZT,8.SP. Blue: Group-I; red: Group-II; green: Group-III.</p

Locations and sample sizes of 8 populations of <i>L</i>. <i>regale</i> used in the present study.

<p>Locations and sample sizes of 8 populations of <i>L</i>. <i>regale</i> used in the present study.</p

Principal component analysis of 8 populations of <i>L</i>. <i>regale</i>.

<p>Principal component analysis of 8 populations of <i>L</i>. <i>regale</i>.</p

Deep Sequencing and Microarray Hybridization Identify Conserved and Species-Specific MicroRNAs during Somatic Embryogenesis in Hybrid Yellow Poplar

<div><h3>Background</h3><p>To date, several studies have indicated a major role for microRNAs (miRNAs) in regulating plant development, but miRNA-mediated regulation of the developing somatic embryo is poorly understood, especially during early stages of somatic embryogenesis in hardwood plants. In this study, Solexa sequencing and miRNA microfluidic chips were used to discover conserved and species-specific miRNAs during somatic embryogenesis of hybrid yellow poplar (<em>Liriodendron tulipifera</em>×<em>L. chinense</em>).</p> <h3>Methodology/Principal Findings</h3><p>A total of 17,214,153 reads representing 7,421,623 distinct sequences were obtained from a short RNA library generated from small RNAs extracted from all stages of somatic embryos. Through a combination of deep sequencing and bioinformatic analyses, we discovered 83 sequences with perfect matches to known miRNAs from 33 conserved miRNA families and 273 species-specific candidate miRNAs. MicroRNA microarray results demonstrated that many conserved and species-specific miRNAs were expressed in hybrid yellow poplar embryos. In addition, the microarray also detected another 149 potential miRNAs, belonging to 29 conserved families, which were not discovered by deep sequencing analysis. The biological processes and molecular functions of the targets of these miRNAs were predicted by carrying out BLAST search against <em>Arabidopsis thaliana</em> GenBank sequences and then analyzing the results with Gene Ontology.</p> <h3>Conclusions</h3><p>Solexa sequencing and microarray hybridization were used to discover 232 candidate conserved miRNAs from 61 miRNA families and 273 candidate species-specific miRNAs in hybrid yellow poplar. In these predicted miRNAs, 64 conserved miRNAs and 177 species-specific miRNAs were detected by both sequencing and microarray hybridization. Our results suggest that miRNAs have wide-ranging characteristics and important roles during all stages of somatic embryogenesis in this economically important species.</p> </div

The ISSR primer sequences, number of bands observed and assessment of banding patterns.

<p>The ISSR primer sequences, number of bands observed and assessment of banding patterns.</p

Nei’s unbiased (1978) measures of genetic distance (below the diagonal) and Pairwise <i>F</i>_st (above the diagonal) observed in 8 populations of <i>L</i>. <i>regale</i>.

<p>Nei’s unbiased (1978) measures of genetic distance (below the diagonal) and Pairwise <i>F</i>_st (above the diagonal) observed in 8 populations of <i>L</i>. <i>regale</i>.</p

Measures of genetic diversity and inbreeding coefficients in 8 populations of <i>L</i>. <i>regale</i>.

<p>Measures of genetic diversity and inbreeding coefficients in 8 populations of <i>L</i>. <i>regale</i>.</p

Transcriptome Characteristics and Six Alternative Expressed Genes Positively Correlated with the Phase Transition of Annual Cambial Activities in Chinese Fir (<i>Cunninghamia lanceolata</i> (Lamb.) Hook)

<div><p>Background</p><p>The molecular mechanisms that govern cambial activity in angiosperms are well established, but little is known about these molecular mechanisms in gymnosperms. Chinese fir (<i>Cunninghamia lanceolata</i> (Lamb.) Hook), a diploid (2<i>n</i>  = 2<i>x</i>  = 22) gymnosperm, is one of the most important industrial and commercial timber species in China. Here, we performed transcriptome sequencing to identify the repertoire of genes expressed in cambium tissue of Chinese fir.</p><p>Methodology/Principal Findings</p><p>Based on previous studies, the four stage-specific cambial tissues of Chinese fir were defined using transmission electron microscopy (TEM). In total, 20 million sequencing reads (3.6 Gb) were obtained using Illumina sequencing from Chinese fir cambium tissue collected at active growth stage, with a mean length of 131 bp and a N50 of 90 bp. SOAPdenovo software was used to assemble 62,895 unigenes. These unigenes were further functionally annotated by comparing their sequences to public protein databases. Expression analysis revealed that the altered expression of six homologous genes (<i>ClWOX1</i>, <i>ClWOX4</i>, <i>ClCLV1</i>-<i>like</i>, <i>ClCLV</i>-<i>like</i>, <i>ClCLE12</i>, and <i>ClPIN1</i>-<i>like</i>) correlated positively with changes in cambial activities; moreover, these six genes might be directly involved in cambial function in Chinese fir. Further, the full-length cDNAs and DNAs for <i>ClWOX1</i> and <i>ClWOX4</i> were cloned and analyzed.</p><p>Conclusions</p><p>In this study, a large number of tissue/stage-specific unigene sequences were generated from the active growth stage of Chinese fir cambium. Transcriptome sequencing of Chinese fir not only provides extensive genetic resources for understanding the molecular mechanisms underlying cambial activities in Chinese fir, but also is expected to be an important foundation for future genetic studies of Chinese fir. This study indicates that <i>ClWOX1</i> and <i>ClWOX4</i> could be possible reverse genetic target genes for revealing the molecular mechanisms of cambial activities in Chinese fir.</p></div