17 research outputs found
Crystallographic Data for Ammonium Nitrate-Sulphate
Engineered
nanoparticles (ENPs) exhibit unique properties advantageous
in a number of applications, but they also represent potential health
and environmental risks. In this study, we investigated the phytotoxic
mechanism of CuO ENPs using transcriptomic analysis and compared this
response with the response to CuO bulk particles and ionic Cu<sup>2+</sup>. Ionic Cu<sup>2+</sup> at the concentration of 0.16 mg L<sup>–1</sup> changed transcription of 2692 genes (<i>p</i> value of <0.001, fold change of ≥2) after 7 days of exposure,
whereas CuO ENPs and bulk particles (both in the concentration of
10 mg L<sup>–1</sup>) altered the expression of 922 and 482
genes in <i>Arabidopsis thaliana</i> roots, respectively.
The similarity between transcription profiles of plants exposed to
ENPs and ionic Cu<sup>2+</sup> indicated that the main factor in phytotoxicity
was the release of Cu<sup>2+</sup> ions from CuO ENPs after 7 days
of exposure. The effect of Cu<sup>2+</sup> ions was evident in all
treatments, as indicated by the down-regulation of genes involved
in metal homeostasis and transport and the up-regulation of oxidative
stress response genes. ENPs were more soluble than bulk particles,
resulting in the up-regulation of metallochaperone-like genes or the
down-regulation of aquaporins and metal transmembrane transporters
that was also characteristic for ionic Cu<sup>2+</sup> exposure
Possible coupling between magnons and phonons in multiferroic CaMn7O12
Spin and lattice dynamics of CaMn7O12 ceramics were investigated using
infrared, THz and inelastic neutron scattering (INS) spectroscopies in the
temperature range 2 to 590 K, and, at low temperatures, in applied magnetic
fields of up to 12 T. On cooling, we observed phonon splitting accompanying the
structural phase transition at Tc = 450K as well as the onset of the
incommensurately modulated structure at 250 K. In the two antiferromagnetic
phases below T_N1 = 90K and T_N2 = 48 K, several infrared-active excitations
emerge in the meV range; their frequencies correspond to the maxima in the
magnon density of states obtained by INS. At the magnetic phase transitions,
these modes display strong anomalies and for some of them, a transfer of
dielectric strength from the higher-frequency phonons is observed. We propose
that these modes are electromagnons. Remarkably, at least two of these modes
remain active also in the paramagnetic phase; for this reason, we call them
paraelectromagnons. In accordance with this observation, quasielastic neutron
scattering revealed short-range magnetic correlations persisting within
temperatures up to 500K above T_N1
Boxnep - модульный подводный робот перспективных технологий
The article discusses the relevance of the underwater vehicles are able to solve a wide range of problems. The decision puts in a basis of the research is designing a modular underwater robot. It allows to make a mounting of various equipment and testing it in the water medium. The paper deals with the concept of the robot and its characteristics
Current Screening Strategies for Pancreatic Cancer
Pancreatic ductal adenocarcinoma (PDAC) is a dreaded malignancy with a dismal 5-year survival rate despite maximal efforts on optimizing treatment strategies. Radical surgery is the only potential curative procedure. Unfortunately, the majority of patients are diagnosed with locally advanced or metastatic disease, which renders them ineligible for curative resection. Early detection of PDAC is thus considered to be the most effective way to improve survival. In this regard, pancreatic screening has been proposed to improve results by detecting asymptomatic stages of PDAC and its precursors. There is now evidence of benefits of systematic surveillance in high-risk individuals, and the current guidelines emphasize the potential of screening to affect overall survival in individuals with genetic susceptibility syndromes or familial occurrence of PDAC. Here we aim to summarize the current knowledge about screening strategies for PDAC, including the latest epidemiological data, risk factors, associated hereditary syndromes, available screening modalities, benefits, limitations, as well as management implications
Evaluation of antimicrobial and anti-inflammatory activities of seed extracts from six Nigella species
Seed extracts from six species of the genus Nigella (Family Ranunculaceae)—Nigella arvensis, Nigella damascena, Nigella hispanica, Nigella nigellastrum, Nigella orientalis, and Nigella sativa—obtained by successive extraction with n-hexane, chloroform, and methanol, were tested for their antimicrobial activity against 10 strains of pathogenic bacteria and yeast using the microdilution method as well as for anti-inflammatory properties by in vitro cyclooxygenase (COX)-1 and COX-2 assay. Chemical characterization of active extracts was carried out including free and fixed fatty acid analysis. Comparison of antimicrobial activity showed that N. arvensis chloroform extract was the most potent among all species tested, inhibiting Gram-positive bacterial and yeast strains with minimum inhibitory concentration (MIC) values ranging from 0.25 to 1 mg/mL. With the exception of selective inhibitory action of n-hexane extract of N. orientalis on growth of Bacteroides fragilis (MIC = 0.5 mg/mL), we observed no antimicrobial activity for other Nigella species. Anti-inflammatory screening revealed that N. sativa, N. orientalis, N. hispanica, N. arvensis n-hexane, and N. hispanica chloroform extracts had strong inhibitory activity (more than 80%) on COX-1 and N. orientalis, N. arvensis, and N. hispanica n-hexane extracts were most effective against COX-2, when the concentration of extracts was 100 μg/mL in both COX assays. In conclusion, N. arvensis, N. orientalis, and N. hispanica seeds, for the first time examined for antimicrobial and anti-inflammatory effects, revealed their significant activity in one or both assays
Impact of Wines and Wine Constituents on Cyclooxygenase-1, Cyclooxygenase-2, and 5-Lipoxygenase Catalytic Activity
Cyclooxygenases and lipoxygenases are proinflammatory enzymes; the former affects platelet aggregation, vasoconstriction, vasodilatation and later the development of atherosclerosis. Red wines from Georgia and central and western Europe inhibited cyclooxygenase-1 (COX-1) activity in the range of 63–94%, cyclooxygenase-2 (COX-2) activity in the range of 20–44% (tested at a concentration of 5 mL/L), and 5-lipoxygenase (5-LOX) activity in the range of 72–84% (at a concentration of 18.87 mL/L). White wines inhibited 5-LOX in the range of 41–68% at a concentration of 18.87 mL/L and did not inhibit COX-1 and COX-2. Piceatannol (IC50 = 0.76 μM) was identified as a strong inhibitor of 5-LOX followed by luteolin (IC50 = 2.25 μM), quercetin (IC50 = 3.29 μM), and myricetin (IC50 = 4.02 μM). trans-Resveratrol was identified as an inhibitor of COX-1 (IC50 = 2.27 μM) and COX-2 (IC50 = 3.40 μM). Red wine as a complex mixture is a powerful inhibitor of COX-1, COX-2, and 5-LOX, the enzymes involved in eicosanoid biosynthetic pathway
The Transcriptomic Response of <i>Arabidopsis thaliana</i> to Zinc Oxide: A Comparison of the Impact of Nanoparticle, Bulk, and Ionic Zinc
The
impact of nanosize was evaluated by comparing of the transcriptomic
response of <i>Arabidopsis thaliana</i> roots to ZnO nanoparticles
(nZnO), bulk ZnO, and ionic Zn<sup>2+</sup>. Microarray analyses revealed
416 up- and 961 down-regulated transcripts (expression difference
>2-fold, p [FDR] < 0.01) after a seven-day treatment with nZnO
(average particle size 20 nm, concentration 4 mg L<sup>–1</sup>). Exposure to bulk ZnO resulted in 816 up- and 2179 down-regulated
transcripts. The most dramatic changes (1711 transcripts up- and 3242
down-regulated) were caused by the presence of ionic Zn<sup>2+</sup> (applied as ZnSO<sub>4</sub>.7H<sub>2</sub>0 at a concentration
of 14.14 mg L<sup>–1</sup>, corresponding to the amount of
Zn contained in 4 mg L<sup>–1</sup> ZnO). Genes involved in
stress response (e.g., to salt, osmotic stress or water deprivation)
were the most relatively abundant group of gene transcripts up-regulated
by all three Zn treatments while genes involved in cell organization
and biogenesis (e.g., tubulins, arabinogalactan proteins) and DNA
or RNA metabolism (e.g., histones) were the most relatively abundant
groups of down-regulated transcripts. The similarity of the transcription
profiles and the increasing number of changed transcripts correlating
with the increased concentration of Zn<sup>2+</sup> in cultivation
medium indicated that released Zn<sup>2+</sup> may substantially contribute
to the toxic effect of nZnO because particle size has not demonstrated
a decisive role