Influence of natural polysaccharides on the morphology and properties of hybrid vaterite microcrystals.

Co-precipitation of biopolymers into calcium carbonate crystals changes their physicochemical and biological properties. This work studies hybrid microcrystals of vaterite obtained in the presence of natural polysaccharides, as carriers for the delivery of proteins and enzymes. Hybrid microcrystals with dextran sulfate, chondroitin sulfate, heparin, fucoidan, and pectin were obtained and compared.

Antitumor effect of nanophotothermolysis mediated by zinc phthalocyanine particles.

Nanophotothermolysis (NPhT) effect is considered to be an approach for the development of highly selective modalities for anticancer treatment. Herein, we evaluated an antitumor efficacy of NPhT with intravenously injected zinc phthalocyanine particles (ZnPcPs) in murine subcutaneous syngeneic tumor models. In S37 sarcoma-bearing mice a biodistribution of ZnPcPs was studied and the high antitumor efficacy of ZnPcPs-mediated NPhT was shown, including a response of metastatic lesions.

Evolution of transition metal dichalcogenide film properties during chemical vapor deposition: from monolayer islands to nanowalls.

Unique properties possessed by transition metal dichalcogenides (TMDs) attract much attention in terms of investigation of their formation and dependence of their characteristics on the production process parameters. Here, we investigate the formation of TMD films during chemical vapor deposition (CVD) in a mixture of thermally activated gaseous HS and vaporized transition metals. Our observations of changes in morphology, Raman spectra, and photoluminescence (PL) properties in combination withmeasurements of the electrical conductivity of the deposits formed at various precursor concentrations and CVD durations are evidence of existence of particular stages in the TMD material formation.

Surface Glycans of Microvesicles Derived from Endothelial Cells, as Probed Using Plant Lectins.

Glycans of MVs are proposed to be candidates for mediating targeting specificity or at least promoting it. In contrast to exosomes, glycomic studies of MVs are largely absent. We studied the glycoprofile of endothelial cell-derived MVs using 21 plant lectins, and the results show the dominance of oligolactosamines and their α2-6-sialylated forms as N-glycans and low levels of α2-3-sialylated glycans.

The Synthesis and Analysis of the Cytotoxicity of AlO-Supported Silver Nanoparticles Prepared by the Plasma Chemical Process Initiated by Pulsed MW Radiation in the AlO-Ag Powder Mixtures.

An original plasma chemical process initiated by microwave discharge in a mixture of metal and dielectric powders was applied to prepare specific materials, which consisted of microsized spherical particles of aluminum oxide covered with silver nanoparticles. The prepared materials are highly uniform in shape, size distribution, and composition. Their cytotoxicity was investigated using the human cell lines MCF7, HEK293T, A549, and VA-13 and the bacterial strains JW5503 (ΔtolC) and K12.

Identification of Ultrastructural Details of the Astrocyte Process System in Nervous Tissue of the Brain Using Correlative Scanning Probe and Transmission Electron Microscopy.

Nanoscale morphological features of branched processes of glial cells may be of decisive importance for neuron-astrocyte interactions in health and disease. The paper presents the results of a correlation analysis of images of thin processes of astrocytes in nervous tissue of the mouse brain, which were obtained by scanning probe microscopy (SPM) and transmission electron microscopy (TEM) with high spatial resolution. Samples were prepared and imaged using a unique hardware combination of ultramicrotomy and SPM.

Incorporation of Pectin into Vaterite Microparticles Prevented Effects of Adsorbed Mucin on Neutrophil Activation.

The application of vaterite microparticles for mucosal delivery depends on their interaction with mucin and immune cells. As we have shown previously, the binding of mucin onto particles enhances the generation of reactive oxygen species by neutrophils. The attenuation of the pro-oxidant effect of the bound mucin through the modification of vaterite could improve its biocompatibility.

Single-step extraction of small-diameter single-walled carbon nanotubes in the presence of riboflavin.

We propose a novel approach to disperse and extract small-diameter single-walled carbon nanotubes (SWCNTs) using an aqueous solution of riboflavin and Sephacryl gel. The extraction of small-diameter semiconducting SWCNTs was observed, regardless of the initial diameter distribution of the SWCNTs. Dispersion of SWCNTs occurs due to the adsorption of π-conjugated isoalloxazine moieties on the surface of small-diameter nanotubes and interactions between hydroxy groups of ribityl chains with water.

Bioresource-derived colloidal nitrogen-doped graphene quantum dots as ultrasensitive and stable nanosensors for detection of cancer and neurotransmitter biomarkers.

Rapid and accurate detection of cancer and neurological diseases is a major issue that has received great attention recently to enable early therapy treatment. In this report, we utilize an atmospheric pressure microplasma system to convert a natural bioresource chitosan into nitrogen-doped graphene quantum dots (NGQDs) for photoluminescence (PL) based selective detection of cancer and neurotransmitter biomarkers. By adjusting the pH conditions during the detection, multiple biomolecules including uric acid (UA), folic acid (FA), epinephrine (EP), and dopamine (DA) can be simultaneously detected with high selectivity and sensitivity using a single material only.

Bacteriophage Possum: A Complex Polysaccharide-Deacetylating Tail Fiber as a Tool for Host Recognition in Pectobacterial .

Novel, closely related phages Possum and Horatius infect , a phytopathogen causing soft rot in potatoes and other essential plants. Their properties and genomic composition define them as N4-like bacteriophages of the genus , a part of a recently formed family . It is proposed that the adsorption apparatus of these phages consists of tail fibers connected to the virion through an adapter protein.

Field Electron Emission from Crumpled CVD Graphene Patterns Printed via Laser-Induced Forward Transfer.

A new approach to the fabrication of graphene field emitters on a variety of substrates at room temperature and in an ambient environment is demonstrated. The required shape and orientation of the graphene flakes along the field are created by the blister-based laser-induced forward transfer of CVD high-quality single-layer graphene. The proposed technique allows the formation of emitting crumpled graphene patterns without losing the quality of the initially synthesized graphene, as shown by Raman spectroscopy.

Magnetic nanoribbons with embedded cobalt grown inside single-walled carbon nanotubes.

Molecular magnetism and specifically magnetic molecules have recently gained plenty of attention as key elements for quantum technologies, information processing, and spintronics. Transition to the nanoscale and implementation of ordered structures with defined parameters is crucial for advanced applications. Single-walled carbon nanotubes (SWCNTs) provide natural one-dimensional confinement that can be implemented for encapsulation, nanosynthesis, and polymerization of molecules into nanoribbons.

Age-Specific Etiology of Severe Acute Respiratory Infections and Influenza Vaccine Effectivity in Prevention of Hospitalization in Russia, 2018-2019 Season.

The expansion and standardization of clinical trials, as well as the use of sensitive and specific molecular diagnostics methods, provide new information on the age-specific roles of influenza and other respiratory viruses in development of severe acute respiratory infections (SARI). Here, we present the results of the multicenter hospital-based study aimed to detect age-specific impact of influenza and other respiratory viruses (ORV). The 2018-2019 influenza season in Russia was characterized by co-circulation of influenza A(H1N1)pdm09 and A(H3N2) virus subtypes which were detected among hospitalized patients with SARI in 19.

Preparation of Copper Surface for the Synthesis of Single-Layer Graphene.

Chemical vapor deposition synthesis of graphene on copper foil from methane is the most promising technology for industrial production. However, an important problem of the formation of the additional graphene layers during synthesis arises due to the strong roughness of the initial copper foil. In this paper, various approaches are demonstrated to form a smooth copper surface before graphene synthesis to reduce the amount of few layer graphene islands.

Helicity-Sensitive Plasmonic Terahertz Interferometer.

Plasmonic interferometry is a rapidly growing area of research with a huge potential for applications in the terahertz frequency range. In this Letter, we explore a plasmonic interferometer based on graphene field effect transistor connected to specially designed antennas. As a key result, we observe helicity- and phase-sensitive conversion of circularly polarized radiation into dc photovoltage caused by the plasmon-interference mechanism: two plasma waves, excited at the source and drain part of the transistor, interfere inside the channel.

Protein nanoparticles: cellular uptake, intracellular distribution, biodegradation and induction of cytokine gene expression.

Intracellular delivery of protein nanoparticles (NP) is required for nanomedicine. Our research was focused on the quantitative analysis of protein NP intracellular accumulation and biodegradation in dynamics along with host cytokine gene expression. Fluorescent NP fabricated by nanoprecipitation without cross-linking of bovine serum albumin (BSA) and human immunoglobulins (hIgG) pre-labeled with Rhodamine B were non-toxic for human cells.

Printing of Crumpled CVD Graphene via Blister-Based Laser-Induced Forward Transfer.

The patterning and transfer of a two-dimensional graphene film without damaging its original structure is an urgent and difficult task. For this purpose, we propose the use of the blister-based laser-induced forward transfer (BB-LIFT), which has proven itself in the transfer of such delicate materials. The ease of implementation of laser techniques reduces the number of intermediate manipulations with a graphene film, increasing its safety.

Bacteriophage Arno 160 Infects via Depolymerization of the Bacterial O-Polysaccharide.

Phytopathogenic bacteria belonging to the and genera (soft-rot ) are in the focus of agriculture-related microbiology because of their diversity, their substantial negative impact on the production of potatoes and vegetables, and the prospects of bacteriophage applications for disease control. Because of numerous amendments in the taxonomy of , there are still a few studied sequenced strains among this species. The present work reports on the isolation and characterization of the phage infectious to the type strain of .

Morphologically Different Bacteriophages PP99 and PP101: Deacetylation of O-Polysaccharide by the Tail Spike Protein of Phage PP99 Accompanies the Infection.

Soft rot caused by numerous species of and is a serious threat to the world production of potatoes. The application of bacteriophages to combat bacterial infections in medicine, agriculture, and the food industry requires the selection of comprehensively studied lytic phages and the knowledge of their infection mechanism for more rational composition of therapeutic cocktails. We present the study of two bacteriophages, infective for the strain F152.

Many-particle excitations in non-covalently doped single-walled carbon nanotubes.

Doping of single-walled carbon nanotubes leads to the formation of new energy levels which are able to participate in optical processes. Here, we investigate (6,5)-single walled carbon nanotubes doped in a solution of hydrochloric acid using optical absorption, photoluminescence, and pump-probe transient absorption techniques. We find that, beyond a certain level of doping, the optical spectra of such nanotubes exhibit the spectral features related to two doping-induced levels, which we assign to a localized exciton [Formula: see text] and a trion T, appearing in addition to an ordinary exciton [Formula: see text].

Films of filled single-wall carbon nanotubes as a new material for high-performance air-sustainable transparent conductive electrodes operating in a wide spectral range.

In this paper we show the advantages of transparent high conductive films based on filled single-wall carbon nanotubes. The nanotubes with internal channels filled with acceptor molecules (copper chloride or iodine) form networks demonstrating significantly improved characteristics. Due to the charge transfer between the nanotubes and filler, the doped-nanotube films exhibit a drop in electrical sheet resistance of an order of magnitude together with a noticeable increase of film transparency in the visible and near-infrared spectral range.

[Etiological structure of influenza and other ARVI in St. Petersburg during epidemic seasons 2012-2016.].

The etiological structure of influenza and other acute respiratory viral infections including their rate of incidence in St. Petersburg and Leningrad region during 4 epidemic seasons has been studied. Seasonality of some respiratory viruses was shown and peaks of circulation of RSV, adenovirus, parainfluenza viruses, rhinovirus, bocavirus, metapneumovirus and coronavirus were marked.

Carbon Nanospikes: Synthesis, characterization and application for high resolution AFM.

We present a detailed study of synthesis, structural characterization of sharp, spike-like carbon structures and its application for high-resolution atomic-force microscopy (AFM) measurements of biological molecules. The probes are obtained by chemical vapor deposition of spike-like carbon structures on the apexes of common AFM silicon probes. The deposition process is carried out in carbonaceous gas mixture activated by a direct-current discharge.