Dual-Responsive Self-Assembled Monolayer for Specific Capture and On-Demand Release of Live Cells

We report a dual-responsive self-assembled monolayer (SAM) on a well-defined rough gold substrate for dynamic capture and release of live cells. By incorporating 5′-triphosphate (ATP) aptamer into a SAM, we can accurately isolate specific cell types and subsequently release captured cells at either population or desired-group (or even single-cell) levels. On one hand, the whole SAMs can be disassembled through addition of ATP solution, leading to the entire release of the captured cells from the supported substrate. On the other hand, desired cells can be selectively released using near-infrared light irradiation, with relatively high spatial and temporal precision. The proposed dual-responsive cell capture-and-release system is biologically friendly and is reusable with another round of modification, showing great usefulness in cancer diagnosis and molecular analysis

code_and_data

This file provides codes and data for analyzing the simulation results

Preclinical and phase I studies of an antisense oligonucleotide drug targeting IGF-1R against liver cancer - Supplementary material

Supplementary Table I Target lesion characteristic in each groupSupplementary Table II Summary of adverse events in each group</p

Quasi-Two-Dimensional SiC and SiC₂: Interaction of Silicon and Carbon at Atomic Thin Lattice Plane

The band gap of graphene is nearly zero, and thus novel two-dimensional (2D) semiconductor and band gap engineering of graphene is highly desired for advanced optoelectronic applications. Herein, we have experimentally produced quasi-two-dimensional (quasi-2D) SiC by reaction between graphene and a silicon source, which was designed and supported by Born–Oppenheimer molecular dynamics simulations. The lateral length of the as-synthesized quasi-2D SiC is mainly in the range of 0.3–5 μm while the thickness is commonly below 10 nm. Quasi-2D SiC₂ is also found as a byproduct, which is stable over 3 months in air atmosphere. The exciton binding energy of quasi-2D multilayers SiC can reach 0.23 eV while the band gap is around 3.72 eV. Additionally, in situ transmission electron microscopy has firmly proven that quasi-2D SiC can be synthesized through the reaction between graphene and silicon quantum dots. The first production of quasi-2D SiC and SiC₂ makes the band gap engineering in the graphene lattice plane possible

Shuttle Suppression by Polymer-Sealed Graphene-Coated Polypropylene Separator

“Shuttle effect” of lithium polysulfides (LiPS) leads to a poor performance and a short cycle life of the Li–S battery, thus limiting their practical application. We demonstrate here that after coating polypropylene (PP) separator with a continuous monolayer graphene, the shuttle effect can be significantly suppressed by limiting the passage of long-chain LiPS. The graphene/PP separator can be further modified by sealing the big holes or pores on graphene with in situ polymerized nylon-66 via an interfacial polymerization reaction between diamine and adipoyl chloride supplied by the aqueous and oil phase, respectively, from each side of the membrane. With this engineered membrane, an initial specific capacity of 1128.4 mAh g^–1 at 0.05C is achieved after test in a coin cell, higher than that of 983.2 mAh g^–1 with pristine PP, along with increased Coulombic efficiency from 96.0 to 99.9% and enhanced cycling durability. Molecular dynamics simulations attest that the nanopores with appropriate size and structure are effective in acting as a “sieve” to selectively allow only Li⁺ ions to pass through but prevent LiPS from migrating to the anode, consequently alleviating the shuttle effect. Our method provides a facile solution toward the mitigated shuttle effect and eventually contributes to the high performance of Li–S battery

Dopamine induces platelet production from megakaryocytes via oxidative stress-mediated signaling pathways

<p>Dopamine (DA), a catecholamine neurotransmitter, is known to for its diverse roles on hematopoiesis, yet its function in thrombopoiesis remains poorly understood. This study shows that DA stimulation can directly induce platelet production from megakaryocytes (MKs) in the final stages of thrombopoiesis via a reactive oxygen species (ROS)-dependent pathway. The mechanism was suggested by the results that DA treatment could significantly elevate the ROS levels in MKs, and time-dependently activate oxidative stress-mediated signaling, including p38 mitogen-activated protein kinase, c-Jun NH2-terminal kinase, and caspase-3 signaling pathways, while the antioxidants N-acetylcysteine and L-glutathione could effectively inhibit the activation of these signaling pathways, as well as the ROS increase and platelet production triggered by DA. Therefore, our data revealed that the direct role and mechanism of DA in thrombopoiesis, which provides new insights into the function recognition of DA in hematopoiesis.</p

Nanowire Templated Semihollow Bicontinuous Graphene Scrolls: Designed Construction, Mechanism, and Enhanced Energy Storage Performance

Graphene scrolls have been widely investigated for applications in electronics, sensors, energy storage, etc. However, graphene scrolls with tens of micrometers in length and with other materials in their cavities have not been obtained. Here nanowire templated semihollow bicontinuous graphene scroll architecture is designed and constructed through “oriented assembly” and “self-scroll” strategy. These obtained nanowire templated graphene scrolls can achieve over 30 μm in length with interior cavities between the nanowire and scroll. It is demonstrated through experiments and molecular dynamic simulations that the semihollow bicontinuous structure construction processes depend on the systemic energy, the curvature of nanowires, and the reaction time. Lithium batteries based on V₃O₇ nanowire templated graphene scrolls (VGSs) exhibit an optimal performance with specific capacity of 321 mAh/g at 100 mA/g and 87.3% capacity retention after 400 cycles at 2000 mA/g. The VGS also shows a high conductivity of 1056 S/m and high capacity of 162 mAh/g at a large density of 3000 mA/g with only 5 wt % graphene added which are 27 and 4.5 times as high as those of V₃O₇ nanowires, respectively. A supercapacitor made of MnO₂ nanowire templated graphene scrolls (MGSs) also shows a high capacity of 317 F/g at 1A/g, which is over 1.5 times than that of MnO₂ nanowires without graphene scrolls. These excellent energy storage capacities and cycling performance are attributed to the unique structure of the nanowire templated graphene scroll, which provides continuous electron and ion transfer channels and space for free volume expansion of nanowires during cycling. This strategy and understanding can be used to synthesize other nanowire templated graphene scroll architectures, which can be extended to other fabrication processes and fields

Hepatitis D Virus Infection of Mice Expressing Human Sodium Taurocholate Co-transporting Polypeptide

<div><p>Hepatitis D virus (HDV) is the smallest virus known to infect human. About 15 million people worldwide are infected by HDV among those 240 million infected by its helper hepatitis B virus (HBV). Viral hepatitis D is considered as one of the most severe forms of human viral hepatitis. No specific antivirals are currently available to treat HDV infection and antivirals against HBV do not ameliorate hepatitis D. Liver sodium taurocholate co-transporting polypeptide (NTCP) was recently identified as a common entry receptor for HDV and HBV in cell cultures. Here we show HDV can infect mice expressing human NTCP (hNTCP-Tg). Antibodies against critical regions of HBV envelope proteins blocked HDV infection in the hNTCP-Tg mice. The infection was acute yet HDV genome replication occurred efficiently, evident by the presence of antigenome RNA and edited RNA species specifying large delta antigen in the livers of infected mice. The resolution of HDV infection appears not dependent on adaptive immune response, but might be facilitated by innate immunity. Liver RNA-seq analyses of HDV infected hNTCP-Tg and type I interferon receptor 1 (<i>IFNα/βR1</i>) null hNTCP-Tg mice indicated that in addition to induction of type I IFN response, HDV infection was also associated with up-regulation of novel cellular genes that may modulate HDV infection. Our work has thus proved the concept that NTCP is a functional receptor for HDV infection <i>in vivo</i> and established a convenient small animal model for investigation of HDV pathogenesis and evaluation of antiviral therapeutics against the early steps of infection for this important human pathogen.</p></div

Intestinal Subepithelial Myofibroblasts Support the Growth of Intestinal Epithelial Stem Cells

<div><p>Intestinal epithelial stem cells (ISCs) are the focus of recent intense study. Current <i>in vitro</i> models rely on supplementation with the Wnt agonist R-spondin1 to support robust growth, ISC self-renewal, and differentiation. Intestinal subepithelial myofibroblasts (ISEMFs) are important supportive cells within the ISC niche. We hypothesized that co-culture with ISEMF enhances the growth of ISCs <i>in vitro</i> and allows for their successful <i>in vivo</i> implantation and engraftment. ISC-containing small intestinal crypts, FACS-sorted single ISCs, and ISEMFs were procured from C57BL/6 mice. Crypts and single ISCs were grown <i>in vitro</i> into enteroids, in the presence or absence of ISEMFs. ISEMFs enhanced the growth of intestinal epithelium <i>in vitro</i> in a proximity-dependent fashion, with co-cultures giving rise to larger enteroids than monocultures. Co-culture of ISCs with supportive ISEMFs relinquished the requirement of exogenous R-spondin1 to sustain long-term growth and differentiation of ISCs. Mono- and co-cultures were implanted subcutaneously in syngeneic mice. Co-culture with ISEMFs proved necessary for successful <i>in vivo</i> engraftment and proliferation of enteroids; implants without ISEMFs did not survive. ISEMF whole transcriptome sequencing and qPCR demonstrated high expression of specific R-spondins, well-described Wnt agonists that supports ISC growth. Specific non-supportive ISEMF populations had reduced expression of R-spondins. The addition of ISEMFs in intestinal epithelial culture therefore recapitulates a critical element of the intestinal stem cell niche and allows for its experimental interrogation and biodesign-driven manipulation.</p></div

Histology of <i>in vitro</i> co-cultures on top of ISEMFs after 7 days.

<p>(A) Hematoxylin and eosin (H&E). (B–G) Immunohistochemical staining for (B) α-SMA, (C) E-Cadherin, (D) caudal type homeobox 2 (Cdx2), (E) lysozyme, (F) synaptophysin, and (G) periodic acid-Schiff (PAS). The scale bar represents 50 µm.</p