Ruthenium nanocrystal decorated vertical graphene nanosheets@Ni foam as highly efficient cathode catalysts for lithium-oxygen batteries

The electrochemical performance of lithium-oxygen (Li-O2) batteries can be markedly improved through designing the architecture of cathode electrodes with sufficient spaces to facilitate the diffusion of oxygen and accommodate the discharge products, and optimizing the cathode catalyst to promote the oxygen reduction reaction and oxygen evolution reaction (OER). Herein, we report the synthesis of ruthenium (Ru) nanocrystal-decorated vertically aligned graphene nanosheets (VGNS) grown on nickel (Ni) foam. As an effective binder-free cathode catalyst for Li-O2 batteries, the Ru-decorated VGNS@Ni foam can significantly reduce the charge overpotential via the effects on the OER and achieve high specific capacity, leading to an enhanced electrochemical performance. The Ru-decorated VGNS@Ni foam electrode has demonstrated low charge overpotential of ~0.45 V and high reversible capacity of 23 864 mAh g−1 at the current density of 200 mA g−1, which can be maintained for 50 cycles under full charge and discharge testing condition in the voltage range of 2.0-4.2 V. Furthermore, Ru nanocrystal decorated VGNS@Ni foam can be cycled for more than 200 cycles with a low overpotential of 0.23 V under the capacity curtained to be 1000 mAh g−1 at a current density of 200 mA g−1. Ru-decorated VGNS@Ni foam electrodes have also achieved excellent high rate and long cyclability performance. This superior electrochemical performance should be ascribed to the unique three-dimensional porous nanoarchitecture of the VGNS@Ni foam electrodes, which provide sufficient pores for the diffusion of oxygen and storage of the discharge product (Li2O2), and the effective catalytic effect of Ru nanocrystals on the OER, respectively. Ex situ field emission scanning electron microscopy, X-ray diffraction, Raman and Fourier transform infrared measurements revealed that Ru-decorated VGNS@Ni foam can effectively decompose the discharge product Li2O2, facilitate the OER and lead to a high round-trip efficiency. Therefore, Ru-decorated VGNS@Ni foam is a promising cathode catalyst for rechargeable Li-O2 batteries with low charge overpotential, long cycle life and high specific capacity

Association of pathway mutation with survival after recurrence in colorectal cancer patients treated with adjuvant fluoropyrimidine and oxaliplatin chemotherapy

Background Although the prognostic biomarkers associated with colorectal cancer (CRC) survival are well known, there are limited data on the association between the molecular characteristics and survival after recurrence (SAR). The purpose of this study was to assess the association between pathway mutations and SAR. Methods Of the 516 patients with stage III or high risk stage II CRC patients treated with surgery and adjuvant chemotherapy, 87 who had distant recurrence were included in the present study. We analyzed the association between SAR and mutations of 40 genes included in the five critical pathways of CRC (WNT, P53, RTK-RAS, TGF-β, and PI3K). Results Mutation of genes within the WNT, P53, RTK-RAS, TGF-β, and PI3K pathways were shown in 69(79.3%), 60(69.0%), 57(65.5%), 21(24.1%), and 19(21.8%) patients, respectively. Patients with TGF-β pathway mutation were younger and had higher incidence of mucinous adenocarcinoma (MAC) histology and microsatellite instability-high. TGF-β pathway mutation (median SAR of 21.6 vs. 44.4 months, p = 0.021) and MAC (20.0 vs. 44.4 months, p = 0.003) were associated with poor SAR, and receiving curative resection after recurrence was associated with favorable SAR (Not reached vs. 23.6 months, p <  0.001). Mutations in genes within other critical pathways were not associated with SAR. When MAC was excluded as a covariate, multivariate analysis revealed TGF-β pathway mutation and curative resection after distant recurrence as an independent prognostic factor for SAR. The impact of TGF-β pathway mutations were predicted using the PROVEAN, SIFT, and PolyPhen-2. Among 25 mutations, 23(92.0%)-24(96.0%) mutations were predicted to be damaging mutation. Conclusions Mutation in genes within TGF-β pathway may have negative prognostic role for SAR in CRC. Other pathway mutations were not associated with SAR.This research was supported by the Seoul National University Hospital (SNUH) Research Fund (03–2014-0440) and a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (grant number: HI14C1277 and HI13C2163). The funding bodies had no influence on the design of the study and collection, analysis, and interpretation of data and in writing the manuscript

Targeted next-generation sequencing-based detection of microsatellite instability in colorectal carcinomas.

In the present study, we developed a computational method and panel markers to assess microsatellite instability (MSI) using a targeted next-generation sequencing (NGS) platform and compared the performance of our computational method, mSILICO, with that of mSINGS to detect MSI in CRCs. We evaluated 13 CRC cell lines, 84 fresh and 119 formalin-fixed CRC tissues (including 61 MSI-high CRCs and 155 microsatellite-stable CRCs) and tested the classification performance of the two methods on 23, 230, and 3,154 microsatellite markers. For the fresh tissue and cell line samples, mSILICO showed a sensitivity of 100% and a specificity of 100%, regardless of the number of panel markers, whereas for the formalin-fixed tissue samples, mSILICO exhibited a sensitivity of up to 100% and a specificity of up to 100% with three differently sized panels ranging from 23 to 3154. These results were similar to those of mSINGS. With the application of mSILICO, the small panel of 23 markers had a sensitivity of ≥95% and a specificity of 100% in cell lines/fresh tissues and formalin-fixed tissues of CRC. In conclusion, we developed a new computational method and microsatellite marker panels for the determination of MSI that does not require paired normal tissues. A small panel could be integrated into the targeted NGS panel for the concurrent analysis of single nucleotide variations and MSI

Blood transcriptome comparison between sexes and their function in 4-week Rhode Island red chickens

Sex is a major biological factor in the development and physiology of a sexual reproductive organism, and its role in the growing process is needed to be investigated in various species. We compare blood transcriptome between 5 males and 5 females in 4-week-old Rhode Island Red chickens and perform functional annotation of differentially expressed genes (DEGs). The results are as follows. 141 and 109 DEGs were located in autosomes and sex chromosomes, respectively. The gene ontology (GO) terms are significantly (p p SMAD2W and the BMP5 were involved in the TGF-beta signaling pathway, and both play an important role in maintaining tissue development. The major DEGs related to the development of neurons and synapses include the up-regulated NRN1, GDF10, SLC1A1, BMP5, NBEA, and NRXN1. Also, 7 DEGs were validated using RT-qPCR with high correlation (r2 = 0.74). In conclusion, the differential expression of blood tissue in the early growing chicken was enriched in TGF-beta signaling and related to the development of neurons and synapses including SMAD2W and BMP5. These results suggest that blood in the early growing stage is differentially affected in tissue development, nervous system, and pigmentation by sex. For future research, experimental characterization of DEGs and a holistic investigation of various tissues and growth stages will be required.</p

Dynamic Ligand Screening by Magnetic Nanoassembly Modulates Stem Cell Differentiation

In native microenvironment, diverse physical barriers exist to dynamically modulate stem cell recruitment and differentiation for tissue repair. In this study, nanoassembly-based magnetic screens of various sizes are utilized, and they are elastically tethered over an RGD ligand (cell-adhesive motif)-presenting material surface to generate various nanogaps between the screens and the RGDs without modulating the RGD density. Large screens exhibiting low RGD distribution stimulate integrin clustering to facilitate focal adhesion, mechanotransduction, and differentiation of stem cells, which are not observed with small screens. Magnetic downward pulling of the large screens decreases the nanogaps, which dynamically suppress the focal adhesion, mechanotransduction, and differentiation of stem cells. Conversely, magnetic upward pulling of the small screens increases the nanogaps, which dynamically activates focal adhesion, mechanotransduction, and differentiation of stem cells. This regulation mechanism is also shown to be effective in the microenvironment in vivo. Further diversifying the geometries of the physical screens can further enable diverse modalities of multifaceted and safe unscreening of the distributed RGDs to unravel and modulate stem cell differentiation for tissue repair.N