The rapid emergence of antimicrobial resistant Gram-negative bacteria compromises current antibiotic efficacy, including the last-resort antibiotic polymyxins, emphasizing the urgent need for novel therapeutic strategies. Nanoscale-based antimicrobials exhibit potential as an alternative treatment strategy. In this study, four furoxan-based nitric oxide (NO)-releasing nanoparticles (NPs) were prepared and their antimicrobial efficacy was tested against different Gram-negative bacteria, including: , , , and via minimum inhibitory testing, where NPs exhibited selective activity against lipopolysaccharide (LPS)-deficient strains and LPS-truncated strains tested.
View Article and Find Full Text PDFTwo-dimensional (2D) kagome metals offer a unique platform for exploring electron correlation phenomena derived from quantum many-body effects. Here, we report a combined study of electrical magnetotransport and neutron scattering on YbFe_{6}Ge_{6}, where the Fe moments in the 2D kagome layers exhibit an A-type collinear antiferromagnetic order below T_{N}≈500 K. Interactions between the Fe ions in the layers and the localized Yb magnetic ions in between reorient the c-axis-aligned Fe moments to the kagome plane below T_{SR}≈63 K.
View Article and Find Full Text PDFAdv Sci (Weinh)
February 2025
This study reveals the mechanisms behind the ultralow lattice thermal conductivity κ in β-ZnSb single crystals through inelastic neutron scattering (INS). Analyzing phonon behaviors and the interaction between acoustic phonons and rattling modes, the first experimental evidence of avoided crossing in β-ZnSb is provided. The rattler-phonon avoided crossings contribute to the low κ in a β-ZnSb single crystal, enhancing the thermoelectric figure-of-merit (zT).
View Article and Find Full Text PDFPhonon dynamics in organic-inorganic hybrid perovskites (OIHPs) exhibit inherent complexity driven by the intricate interactions between rotatable organic cations and dynamically disordered inorganic octahedra, mediated by hydrogen bonding. This study aims to address this complexity by investigating the thermal transport behavior of MAPbCl as a gateway to the OIHPs family. The results reveal that the ultralow thermal conductivity of MAPbCl arises from a synergistic interplay of exceptionally low phonon velocities, short phonon lifetimes, and phonon mean free paths approaching the Regel-Ioffe limit.
View Article and Find Full Text PDFJ Phys Condens Matter
February 2024
ACS Appl Mater Interfaces
January 2024
The extracellular matrix (ECM) is the fundamental acellular element of human tissues, providing their mechanical structure while delivering biomechanical and biochemical signals to cells. Three-dimensional (3D) tissue models commonly use hydrogels to recreate the ECM and support the growth of cells as organoids and spheroids. Collagen-nanocellulose (COL-NC) hydrogels rely on the blending of both polymers to design matrices with tailorable physical properties.
View Article and Find Full Text PDFNat Commun
January 2022
A depleted antimicrobial drug pipeline combined with an increasing prevalence of Gram-negative 'superbugs' has increased interest in nano therapies to treat antibiotic resistance. As cubosomes and polymyxins disrupt the outer membrane of Gram-negative bacteria via different mechanisms, we herein examine the antimicrobial activity of polymyxin-loaded cubosomes and explore an alternative strategy via the polytherapy treatment of pathogens with cubosomes in combination with polymyxin. The polytherapy treatment substantially increases antimicrobial activity compared to polymyxin B-loaded cubosomes or polymyxin and cubosomes alone.
View Article and Find Full Text PDFBiochim Biophys Acta Biomembr
September 2021
ACS Appl Mater Interfaces
October 2020
Treatment of multidrug-resistant (MDR) bacterial infections increasingly relies on last-line antibiotics, such as polymyxins, with the urgent need for discovery of new antimicrobials. Nanotechnology-based antimicrobials have gained significant importance to prevent the catastrophic emergence of MDR over the past decade. In this study, phytantriol-based nanoparticles, named cubosomes, were prepared and examined by minimum inhibitory concentration (MIC) and time-kill assays against Gram-negative bacteria: , , and .
View Article and Find Full Text PDFNanomaterials (Basel)
July 2020
Magnetic properties of fully oxygenated bare CuO nanoparticles have been investigated using magnetization, X-ray diffraction, neutron diffraction, and Raman scattering measurements. The Langevin field profile is clearly revealed in the isothermal magnetization of 8.8 nm CuO nanoparticle assembly even at 300 K, revealing a 172 times enhancement of the ferromagnetic responses over that of bulk CuO.
View Article and Find Full Text PDFHypothesis: The water absorption capacity of nanocellulose (NC) foam is tailored by crosslinking with polyethyleneimine (PEI) and hexamethylenediamine (HMDA). The interaction of amine groups in PEI and HMDA with the carboxylic groups (COO) of NC affects the foam structure which reduces its swelling capacity.
Experiments: Functionalised NC foams were prepared by TEMPO (2,2,6,6,-tetramethylpiperidine-1-oxyl) oxidation of bleached pulp, followed by fibrillation into a hydrogel, adding a crosslinker and freeze drying the hydrogel into a foam.
Ultraviolet irradiation (UVI) of varied duration caused cross-linking and neutralization of polystyrene (PS) homopolymers of molar mass () from 6 to 290 kg mol on a silicon-oxide surface. An optimal neutral skin layer on the surface of the PS was obtained via brief UVI in air (UVIA), by which the PS had no preferential interaction with either block in the copolymer. UVI in an inert environment (gaseous dinitrogen) (UVIN) stabilized the PS layers via cross-linking and enabled the PS networks to have an effective adhesive contact with the underlying substrate.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
February 2019
is a notorious human bacterial pathogen with considerable capacity to develop antibiotic resistance. We have observed that human infections caused by highly drug-resistant are more prolonged, complicated, and difficult to eradicate. Here we describe a metabolic adaptation strategy used by clinical strains that leads to resistance to the last-line antibiotic, daptomycin, and simultaneously affects host innate immunity.
View Article and Find Full Text PDFWe investigated the relationship between the self-assembled morphology of poly( tert-butyl acrylate)- block-poly(6-[4-(4'-methoxyphenylazo)phenoxy]hexyl methacrylate) (P tBA- b-PAzoMA) block copolymers and their photoresponsive and fluorescence behaviors. The morphology of P tBA- b-PAzoMA copolymers was manipulated by dissolving them in mixed dimethylformamide (DMF)/hexanol solvents. When P tBA- b-PAzoMA was dissolved in DMF-rich (neutral) solvents, a favorable interaction between the DMF molecules and both blocks resulted in a random-coiled conformation.
View Article and Find Full Text PDFA large enhancement of the Ni and Cr ferromagnetic moments under UV-light irradiation has been detected in 55 nm thick KNi[Cr(CN)][(HO)]·0.11HO Prussian blue analogues coated on 240 nm RbCo[Fe(CN)][(HO)]·0.56HO nanocubes.
View Article and Find Full Text PDFThe interactions between ions and phospholipids are closely associated with the structures and functions of cell membrane. Instead of conventional aqueous systems, we systematically investigated the effects of inorganic ions on the self-assembly of lecithin, a zwitterionic phosphatidylcholine, in cyclohexane. Previous studies have shown that addition of inorganic salts with specific divalent and trivalent cations can transform lecithin organosols into organogels.
View Article and Find Full Text PDFCell Physiol Biochem
November 2015
Background: Glioblastoma (GBM) is the most common and most aggressive form of brain cancer. After surgery, radiotherapy is the mainstay of treatment for GBM patients. Unfortunately, the vast majority of GBM patients fail responding to radiotherapy because GBM cells remain highly resistant to radiation.
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