By leveraging the ability of Shewanella oneidensis MR‐1 (S. oneidensis MR‐1) to anaerobically catabolize lactate through the transfer of electrons to metal minerals for respiration, a lactate‐fueled ...biohybrid (Bac@MnO2) was constructed by modifying manganese dioxide (MnO2) nanoflowers on the S. oneidensis MR‐1 surface. The biohybrid Bac@MnO2 uses decorated MnO2 nanoflowers as electron receptor and the tumor metabolite lactate as electron donor to make a complete bacterial respiration pathway at the tumor sites, which results in the continuous catabolism of intercellular lactate. Additionally, decorated MnO2 nanoflowers can also catalyze the conversion of endogenous hydrogen peroxide (H2O2) into generate oxygen (O2), which could prevent lactate production by downregulating hypoxia‐inducible factor‐1α (HIF‐1α) expression. As lactate plays a critical role in tumor development, the biohybrid Bac@MnO2 could significantly inhibit tumor progression by coupling bacteria respiration with tumor metabolism.
MnO2 nanoflowers were modified on the cell surface of electrochemically active bacteria, S. oneidensis MR‐1. The biohybrids, which couple bacterial respiration with tumor metabolism, can catabolize intercellular lactate and prevent intracellular lactate production in the tumor, thereby inducing significant tumor inhibition.
A
bstract
Compactification of M-theory and of IIB string theory on threefold canonical singularities gives rise to superconformal field theories (SCFTs) in 5d and 4d, respectively. The resolutions ...and deformations of the singularities encode salient features of the SCFTs and of their moduli spaces. In this paper, we build on Part 0 of this series 1 and further explore the physics of SCFTs arising from isolated hypersurface singularities. We study in detail these canonical isolated hypersurface singularities that admit a smooth Calabi-Yau (crepant) resolution. Their 5d and 4d physics is discussed and their 3d reduction and mirrors (the magnetic quivers) are determined in many cases. As an explorative tool, we provide a Mathematica code which computes key quantities for any canonical isolated hypersurface singularity, including the 5d rank, the 4d Coulomb branch spectrum and central charges, higher-form symmetries in 4d and 5d, and crepant resolutions.
African swine fever virus (ASFV) is a giant and complex DNA virus that causes a highly contagious and often lethal swine disease for which no vaccine is available. Using an optimized image ...reconstruction strategy, we solved the ASFV capsid structure up to 4.1 angstroms, which is built from 17,280 proteins, including one major (p72) and four minor (M1249L, p17, p49, and H240R) capsid proteins organized into pentasymmetrons and trisymmetrons. The atomic structure of the p72 protein informs putative conformational epitopes, distinguishing ASFV from other nucleocytoplasmic large DNA viruses. The minor capsid proteins form a complicated network below the outer capsid shell, stabilizing the capsid by holding adjacent capsomers together. Acting as core organizers, 100-nanometer-long M1249L proteins run along each edge of the trisymmetrons that bridge two neighboring pentasymmetrons and form extensive intermolecular networks with other capsid proteins, driving the formation of the capsid framework. These structural details unveil the basis of capsid stability and assembly, opening up new avenues for African swine fever vaccine development.
Direct light‐to‐work conversion enables manipulating remote devices in a contactless, controllable, and continuous manner. Although some pioneering works have already proven the feasibility of ...controlling devices through light‐irradiation‐induced surface tension gradients, challenges remain, including the flexible integration of efficient photothermal materials, multifunctional structure design, and fluidic drag reduction. This paper reports a facile one‐step method for preparing light‐driven floating devices with functional surfaces for both light absorption and drag reduction. The direct laser writing technique is employed for both arbitrary patterning and surface modification. By integrating the functional layer at the desired position or by designing asymmetric structures, three typical light‐driven floating devices with fast linear or rotational motions are demonstrated. Furthermore, these devices can be driven by a variety of light sources including sunlight, a filament lamp, or laser beams. The approach provides a simple, green, and cost‐effective strategy for building functional floating devices and smart light‐driven actuators.
A facile fabrication of superhydrophobic polydimethylsiloxane (PDMS) elastomers structures that permit controllable manipulation via Marangoni effectthat permit controllable manipulation via Marangoni effect is reported here. Direct laser writing technology is employed to apply a light absorbing and superhydrophobic layer on the PDMS surface. By integrating the functional layer at the desired position or by designing asymmetric structures, typical light‐driven devices with fast linear or rotational motions are demonstrated.
•PPy/GO nanocomposites were simply and rapidly prepared by in situ polymerization.•The PPy/GO nanocomposites were functionalized with PA by electrostatic attraction.•The PA/PPy/GO modified electrode ...exhibited a high sensitivity for Cd(II) and Pb(II) detection.
An electrochemical sensor was developed for detecting heavy metal ions by using a phytic acid functionalized polypyrrole (PPy)/graphene oxide (GO) modified electrode. PPy/GO nanocomposites were synthesized by in situ chemical oxidation polymerization. The PPy/GO nanocomposites were functionalized with phytic acid (PA) molecules by electrostatic attraction. The structural features of the fabricated nanocomposites were confirmed by transmission electron microscopy (TEM), attenuated total reflection infrared (ATR-IR) spectroscopy and Raman spectroscopy. The PA/PPy/GO modified electrode exhibited high electrochemical conductivity, and produced a remarkable increase in peak current compared with the PPy/GO and PA/GO modified electrodes. The developed sensor was used for the electrochemical analysis of various trace metal ions by differential pulse voltammetry (DPV). The modified electrode demonstrated to measure Cd(II) and Pb(II) with a linear working range of 5–150μg/L. This work demonstrated a simple, rapid and high performing electrochemical strategy for high-sensitivity detection of heavy metal ions.
Extracellular vesicles (EVs) are the substances that are released by most types of cells and have an important role in cell to cell communication. Among the most highly researched EVs are exosome. ...Recent studies show that exosomes derived from cells have different roles and targets. Many studies show that exosome can efficiently deliver many different kinds of cargo to the target cell. Therefore, they are often used to deliver therapeutic cargo for treatment. The exosomes that have been used include both natural ones and those that have been modified with other substances to increase the delivery ability. This article provides a review of both exosomes derived from various cells and modified exosome and their ability in delivering the many kinds of cargo to the target cell.
Highlights • DSF potently inhibited angiogenesis both in vitro and in vivo. • Cu improves the anti-angiogenic ability of DSF both in vitro and in vivo. • DSF/Cu suppresses VEGF secretion through ...EGFR/c-Src/VEGF pathway.
We propose graphs, the Combined Fiber Diagrams (CFD), to characterize all 5d superconformal field theories (SCFTs) that arise as S1-reductions of 6d SCFTs. Transitions between CFDs encode mass ...deformations that trigger RG-flows between SCFTs. They provide a combinatorial classification of all such 5d SCFTs and encode physical information about the strongly coupled theories, like the superconformal flavor symmetry and BPS states. We consistently reproduce known results, but more importantly predict new theories and strong coupling effects in 5d SCFTs.
5d SCFTs from decoupling and gluing Apruzzi, Fabio; Schäfer-Nameki, Sakura; Wang, Yi-Nan
The journal of high energy physics,
08/2020, Volume:
2020, Issue:
8
Journal Article
Peer reviewed
Open access
A
bstract
We systematically analyse 5d superconformal field theories (SCFTs) obtained by dimensional reduction from 6d
N
= (1
,
0) SCFTs. Such theories have a realization as M-theory on a singular ...Calabi-Yau threefold, from which we determine the so-called combined fiber diagrams (CFD) introduced in 1–3. The CFDs are graphs that encode the superconformal flavor symmetry, BPS states, low energy descriptions, as well as descendants upon flavor matter decoupling. To obtain a 5d SCFT from 6d, there are two approaches: the first is to consider a circle-reduction combined with mass deformations. The second is to circle-reduce and decouple an entire gauge sector from the theory. The former is applicable e.g. for very Higgsable theories, whereas the latter is required to obtain a 5d SCFT from a non-very Higgsable 6d theory. In the M-theory realization the latter case corresponds to decompactification of a set of compact surfaces in the Calabi-Yau threefold. To exemplify this we consider the 5d SCFTs that descend from non-Higgsable clusters and non-minimal conformal matter theories. Finally, inspired by the quiver structure of 6d theories, we propose a gluing construction for 5d SCFTs from building blocks and their CFDs.
The SARS-CoV-2 Omicron variant with increased fitness is spreading rapidly worldwide. Analysis of cryo-EM structures of the spike (S) from Omicron reveals amino acid substitutions forging ...interactions that stably maintain an active conformation for receptor recognition. The relatively more compact domain organization confers improved stability and enhances attachment but compromises the efficiency of the viral fusion step. Alterations in local conformation, charge, and hydrophobic microenvironments underpin the modulation of the epitopes such that they are not recognized by most NTD- and RBD-antibodies, facilitating viral immune escape. Structure of the Omicron S bound with human ACE2, together with the analysis of sequence conservation in ACE2 binding region of 25 sarbecovirus members, as well as heatmaps of the immunogenic sites and their corresponding mutational frequencies, sheds light on conserved and structurally restrained regions that can be used for the development of broad-spectrum vaccines and therapeutics.
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•Omicron spike stably maintains an active conformation for receptor recognition•Improved stability of Omicron enhances attachment but compromises viral fusion•Mutations perturb the conformation of antigenic sites recognized by most antibodies•Structurally restrained regions of RBM can be targets for COVID-19 countermeasures
Mutations in the SARS-CoV-2 Omicron variant improve spike trimer stability that supports viral attachment but appears to compromise viral fusion. They also perturb the confirmation of antigenic sites for antibody recognition, which may contribute to immune evasion.