The spreading of microbial pathogens with more and more resistance to traditional low-molecular antibiotic agents demands new approaches to antibacterial therapy. The employment of bacteriophage enzymes capable of breaking bacterial cell walls has attracted much interest within this context. The specific features of the morphology of Gram-negative bacteria prevent the effective direct usage of lytic enzymes and require assistance from additional helpers to facilitate cell lysis.
View Article and Find Full Text PDFThis review describes methods and results of studying the mechanical properties of wood at all scales: from nano- to macro-scale. The connection between the mechanical properties of material and its structure at all these levels is explored. It is shown that the existing size effects in the mechanical properties of wood, in a range of the characteristic sizes of the structure of about six orders of magnitude, correspond to the empirical Hall-Petch relation.
View Article and Find Full Text PDFThis paper describes an experimental study of the relationships between thermal diffusivity and mechanical characteristics including Brinell hardness, microhardness, and Young's modulus of common pine ( L.), pedunculate oak ( L.), and small-leaf lime ( Mill.
View Article and Find Full Text PDFThe review discusses the theoretical, experimental and toxicological aspects of the prospective biomedical application of functionalized magnetic nanoparticles (MNPs) activated by a low frequency non-heating alternating magnetic field (AMF). In this approach, known as nano-magnetomechanical activation (NMMA), the MNPs are used as mediators that localize and apply force to such target biomolecular structures as enzyme molecules, transport vesicles, cell organelles, etc., without significant heating.
View Article and Find Full Text PDFRemote nano-magneto-mechanical actuation of magnetic nanoparticles (MNPs) by non-heating extremely low frequency magnetic field (ELF MF) is explored as a tool for non-invasive modification of bionanomaterials in pharmaceutical and medical applications. Here we study the effects of ELF MF (30-160 Hz, 8-120 kA/m) on the activity and release of a model enzyme, superoxide dismutase 1 (SOD1) immobilized by polyion coupling on dispersed MNPs aggregates coated with poly(L-lysine)-block-poly(ethylene glycol) block copolymer (s-MNPs). Such fields do not cause any considerable heating of MNPs but promote their rotating-oscillating mechanical motion that produces mechanical forces and deformations in adjacent materials.
View Article and Find Full Text PDFThis work presents direct evidence of disordering of liposomal membranes by magnetic nanoparticles during their exposures to non-heating alternating Extremely Low Frequency Magnetic Field (ELF MF). Changes in the lipid membrane structure were demonstrated by the Attenuated total reflection Fourier Transform Infrared and fluorescence spectroscopy. Specifically, about 50% of hydrophobic chains became highly mobile under the action of ELF MF.
View Article and Find Full Text PDF