3-Nitro-2-phenyl­chroman

In the title compound, C15H13NO3, the dihedral angle between the two aromatic rings is 79.25 (16)°

Multi-field nanoindentation apparatus for measuring local mechanical properties of materials in external magnetic and electric fields

Nano/micro-scale mechanical properties of multiferroic materials can be controlled by the external magnetic or electric field due to the coupling interaction. For the first time, a modularized multi-field nanoindentation apparatus for carrying out testing on materials in external magnetostatic/electrostatic field is constructed. Technical issues, such as the application of magnetic/electric field and the processes to diminish the interference between external fields and the other parts of the apparatus, are addressed. Tests on calibration specimen indicate the feasibility of the apparatus. The load-displacement curves of ferromagnetic, ferroelectric and magnetoelectric materials in the presence/absence of external fields reveal the small-scale magnetomechanical and electromechanical coupling, showing as the Delta-E and Delta-H effects, i.e. the magnetic/electric field induced changes in the apparent elastic modulus and indentation hardness.Comment: 17 pages, 7 figure

Optimizing de novo transcriptome assembly from short-read RNA-Seq data: a comparative study

With the fast advances in nextgen sequencing technology, high-throughput RNA sequencing has emerged as a powerful and cost-effective way for transcriptome study. De novo assembly of transcripts provides an important solution to transcriptome analysis for organisms with no reference genome. However, there lacked understanding on how the different variables affected assembly outcomes, and there was no consensus on how to approach an optimal solution by selecting software tool and suitable strategy based on the properties of RNA-Seq data. To reveal the performance of different programs for transcriptome assembly, this work analyzed some important factors, including k-mer values, genome complexity, coverage depth, directional reads, etc. Seven program conditions, four single k-mer assemblers (SK: SOAPdenovo, ABySS, Oases and Trinity) and three multiple k-mer methods (MK: SOAPdenovo-MK, trans-ABySS and Oases-MK) were tested. While small and large k-mer values performed better for reconstructing lowly and highly expressed transcripts, respectively, MK strategy worked well for almost all ranges of expression quintiles. Among SK tools, Trinity performed well across various conditions but took the longest running time. Oases consumed the most memory whereas SOAPdenovo required the shortest runtime but worked poorly to reconstruct full-length CDS. ABySS showed some good balance between resource usage and quality of assemblies. Our work compared the performance of publicly available transcriptome assemblers, and analyzed important factors affecting de novo assembly. Some practical guidelines for transcript reconstruction from short-read RNA-Seq data were proposed. De novo assembly of C. sinensis transcriptome was greatly improved using some optimized methods

Transcriptional control of Flt3 ligand targeted by fluorouracil-induced Egr-1 promoter in hematopoietic damage

<p>Abstract</p> <p>Background</p> <p>Ionizing radiation (IR) activate the early growth response-1 (Egr-1) promoter by production of radical oxygen intermediates (ROIs). Egr-EF, an expression vector pCIneo containing Egr-1 promoter cloned upstream of the cDNA for Flt3 ligand, was used to treat hematopoietic damage. 5-fluorouracil, a commonly used chemotherapeutic agent, cause tumor cell death by producing DNA damage and generating ROIs. We therefore hypothesized that clinically employed chemotherapeutic agents that increase ROIs could also be employed to activate Egr-EF in a chemoinducible gene therapy strategy. The goal of this study was to explore the effect of Flt3 Ligand gene transcription regulated by fluorouracil-induced Egr-1 promoter on hematopoietic recovery.</p> <p>Methods</p> <p>Human Flt3 Ligand (FL) cDNA and enhanced green fluorescent protein (EGFP) cDNA were linked together with IRES and inserted into the expression vector pCI-neo under control of the Egr-1 promoter (Egr-EF). The vector was transfected into the HFCL human bone marrow stromal cell line, and these cells were exposed to 5-FU, a chemotherapeutic drug. Expression of FL by HFCL/EF cells after 5-FU treatment was determined with ELISA, western blot and RT-PCR assays. In addition, the effect of FL from HFCL/EF cell culture supernatants on growth of CD34⁺cells from cord blood was also studied. HFCL/EF cells were injected into CB-17 combined immunodeficient (SCID) mice with B16 melanoma. 5-FU was given three days after injection of the HFCL/EF cells. In the recipient mice, white blood cell levels in peripheral blood and expression of EGFP and FL in human stromal cells were measured. Tumor volumes in tumor-bearing mice were also measured.</p> <p>Results</p> <p>5-FU treatment increased EGFP levels and secreted FL levels in HFCL/EF cells. Supernatants from HFCL/EF cell cultures treated with 5-FU increased CD34⁺cell growth significantly. HFCL/EF exhibited an increase in the number of white blood cells after chemotherapy.</p> <p>Conclusion</p> <p>The data presented here support the use of transcriptional control mediated by chemoinducible gene therapy to reduce hematopoietic injury associated with 5-FU.</p

Green synthesis of CuO nanoparticles using Cassia auriculata leaf extract and in vitro evaluation of their biocompatibility with rheumatoid arthritis macrophages (RAW 264.7)

Purpose: To undertake green synthesis of copper oxide nanoparticles (CuO NPs) using Cassia auriculata leaf extract and evaluate their biocompatibility with rheumatoid arthritis macrophages (RAW 264.7 cell line).Methods: CuO NPs were prepared by heating a mixture of 10 mL of 0.01 M CuSO4 solution and 30 mL of C. auriculata extract at 80 °C for 1 h. The synthesized CuO NPs were characterized by x-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UVVis), energy-dispersive x-ray spectroscopy (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and dynamic light scattering (DLS). The cytotoxicity of the NPs against RAW 264.7 cells was studied using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay.Results: The gradual change in color of the reaction solution from brownish yellow to dark brown indicated CuO NP formation. TEM images revealed spherical, polydispersed NPs (mean particle size, 23 nm). FTIR results indicated capping of polyphenols on the surface of the NPs. Most RAW 264.7 cells (&gt; 95 %) remained alive following exposure to CuO NPs at concentrations of up to 200 μg/mL, indicating biocompatible with the cells.Conclusion: An eco-friendly, low-cost, biosynthetic method for CuO NP preparation has been successfully developed using C. auriculata leaf extract. Furthermore, the nanoparticles are biocompatible with RAW 264.7 cell line.Keywords: Cassia auriculata extract, Copper oxide nanoparticles, RAW 264.7 cell line, Rheumatoid arthriti

Different Effects of Six Antibiotics and Ten Traditional Chinese Medicines on Shiga Toxin Expression by Escherichia coli

This study compared the effects of ten types of traditional Chinese medicines (TCMs) and six different antibiotics on E. coli O157:H7 Shiga toxin gene (stx2) mRNA expression level based on real-time PCR and the expression level of Stx toxin using an ELISA quantitative assay. We also compared their effects on the induction of the SOS response. The results clearly indicated that all ten TCMs had negative results in the SOS response induction test, while most TCMs did not increase the levels of stx2 mRNA and the Stx toxin. Some TCMs did increase the mRNA levels of the stx2 gene and the Stx toxin level, but their increases were much lower than those caused by antibiotics. With the exception of cefotaxime, the six antibiotics increased the Stx toxin level and increased the stx2 gene mRNA level. With the exceptions of cefotaxime and tetracycline, the antibiotics increased the SOS induction response. These results suggest that TCMs may have advantages compared with antibiotics, when treating E. coli O157:H7; TCMs did not greatly increase Stx toxin production and release