A task-specific ionic liquid with a Bronsted acid (1-(3-sulfopropyl)-3-methylimidazolium hydrogen sulfate, namely MSI) bearing an anionic heteropolyacid derivative (PW12O403−, namely PW) were used as ...an efficient catalyst for the three-component Mannich and Hantzsch reactions. Using (MSI)3PW as the catalyst supported in imidazolium-based ionic liquids allowed these multicomponent reactions to take place in good to excellent yields. The Mannich reaction, performed at room temperature, was also evaluated by means of electrospray (tandem) mass spectrometry—ESI-MS(/MS). ESI-MS data pointed to the origin of the ionic liquid effect, i.e., formation of ion pairs with the charged reaction intermediates and furthers association into larger supramolecular aggregates. DFT calculations revealed the strength of the supramolecular interactions between the charged species detected by ESI-MS and the spontaneity association of these ion pairs affording larger supramolecular aggregates.
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KEPLER RAPIDLY ROTATING GIANT STARS Costa, A. D.; Martins, B. L. Canto; Bravo, J. P. ...
Astrophysical journal. Letters,
07/2015, Letnik:
807, Številka:
2
Journal Article
Recenzirano
Odprti dostop
ABSTRACT Rapidly rotating giant stars are relatively rare and may represent important stages of stellar evolution, resulting from stellar coalescence of close binary systems or accretion of ...substellar companions by their hosting stars. In the present Letter, we report 17 giant stars observed in the scope of the Kepler space mission exhibiting rapid rotation behavior. For the first time, the abnormal rotational behavior for this puzzling family of stars is revealed by direct measurements of rotation, namely from photometric rotation period, exhibiting a very short rotation period with values ranging from 13 to 55 days. This finding points to remarkable surface rotation rates, up to 18 times the rotation of the Sun. These giants are combined with six others recently listed in the literature for mid-infrared (IR) diagnostics based on Wide-field Infrared Survey Explorer information, from which a trend for an IR excess is revealed for at least one-half of the stars, but at a level far lower than the dust excess emission shown by planet-bearing main-sequence stars.
Aims
In‐vitro/In‐vivo evaluation of cholesterol‐lowering probiotic strain Lactobacillus paracasei DTA81 and the possible connection with the gut microbiota modulation.
Methods and Results
In the ...present study, strain DTA81 has been evaluated for the possible influence on blood lipid and glucose concentrations, modulation of the immune system, gastrointestinal survivability and modulation of gut microbiota in BALB/c mice receiving a high‐fat diet. After 6 weeks of treatment, a significant reduction of total cholesterol and fasting blood sugar (FBS) among animals treated with L. paracasei DTA81 has been recorded. Comparison of colon tissue levels of different cytokines revealed a significant reduction of the inflammatory cytokine interleukin‐6. The comparison of gut microbiota using the 16S rRNA approach indicated that the treatment with L. paracasei DTA81 significantly increased the taxa Bacteroidetes and Coprococcus. Moreover, the genome of DTA81 was sequenced for the in‐silico assessment, and the analysis indicated the presence of cholesterol assimilation‐related genes as well as the absence of negative traits such as transmissible antibiotic resistance genes, plasmids and prophage regions.
Conclusion
The outcome of this study revealed the in‐vitro and in‐vivo properties of L. paracasei DTA81 and the possible mechanism between consumption of this strain, the abundance of Bacteriodetes/Coprococcus taxa, immunomodulatory activity and the subsequent reduction of cholesterol/FBS in BALB/c mice.
Significance and Impact of the Study
Lactobacillus paracasei DTA81 as a non‐pharmacological potential probiotic supplement can influence metabolic homeostasis in individuals, particularly those adopting high‐fat diets, and it can contribute to reduce coronary heart disease.
Azathioprine (Aza) is a purine antimetabolite immunosuppressant that is widely employed for immunosuppressive therapy in post-transplant recipients or patients with autoimmune diseases. Chronic use ...of immunosuppressants might produce several side effects, including a high rate of neoplasms in these patients. Considering that genotoxic effects are associated with an increased risk of developing cancer, the aim of this study was to examine the recombinogenic, genotoxic, and cytotoxic effects of Aza using Somatic Mutation and Recombination Test (SMART) in Drosophila melanogaster, as well as comet and micronucleus assays in mouse bone marrow cells. Further, the adverse effects of Aza were determined in mouse hepatic and renal tissues using histopathological analysis. Data demonstrated that Aza induced significant increased genotoxicity in D. melanogaster and mouse bone marrow cells at all concentrations tested. Homologous recombination was the predominant genotoxic event noted for the first time to be initiated by Aza in SMART. In histopathological analysis, Aza did not show any marked toxic activity in mouse hepatic and renal tissues. Therefore, the high rate of neoplasms reported in patients with long-term use of Aza may be attributed, at least partially, to the genotoxic action of this drug.
Summary
Background
Lichen planus (LP) is a chronic inflammatory mucocutaneous disease. Toll‐like receptors (TLRs) bind numerous exogenous and endogenous antigens by recognizing conserved ...pathogen‐associated molecular patterns (PAMPs) and have the ability to induce the production of proinflammatory cytokines. Therefore, alterations in innate immunity could explain the inflammation and T‐cell autoreactivity leading to the development of LP disease.
Objectives
To evaluate how the host innate immune response to PAMPs is affected by cutaneous LP, primarily by using TLR agonists to induce proinflammatory cytokine secretion from peripheral blood mononuclear cells (PBMCs).
Methods
PBMCs from patients with LP and healthy control (HC) individuals were stimulated with agonists of TLR2/TLR1 (pam3csk4), TLR3 poly(I:C)‐RIG, TLR4 (lipopolysaccharide), TLR5 (flagellin), TLR7 (imiquimod), TLR7/TLR8 (CL097) and TLR9 (CpG). Cytokines from culture supernatants (n = 10–12) and serum chemokines and cytokines (n = 22–24) were measured using flow cytometry.
Results
Activation through the TLR2, TLR4 and TLR5 pathways induced increased tumour necrosis factor (TNF)‐α secretion by PBMCs from individuals with LP compared with the HC group. In contrast, activation through TLR3 and TLR7 was impaired in the LP group, leading to decreased TNF‐α secretion. Moreover, intracellular TLR activation resulted in reduced interleukin (IL)‐1β and IL‐6 secretion. Notably, individuals with LP became responders on stimulation with TLR7/TLR8 and TLR9 agonists; responses were measured as increases in interferon (IFN)‐α production. Detectable TNF‐α and high CXCL9 and CXCL10 serum levels were observed in patients with LP, suggesting their potential use as markers of the inflammatory status in LP.
Conclusions
These findings point to a defect in the TLR signalling pathways in cutaneous LP. Agonists of TLR7/TLR8 or TLR9 overcame impaired IFN‐α secretion in LP, strategically acting as adjuvants to improve the type I response.
What's already known about this topic?
Existing information on innate immunity in lichen planus (LP) has largely come from studies of Toll‐like receptor (TLR) expression in skin lesions.
What does this study add?
A dysfunctional innate immune response was observed with LP, as demonstrated by enhanced tumour necrosis factor responsiveness to extracellular TLR activation and an absent type I interferon (IFN) response induced by TLR3 and TLR7 agonists.
Agonists for the TLR7/TLR8 or TLR9 pathways were able to drive IFN‐α secretion, suggesting that they may serve as effective adjuvants to improve the antiviral immune response.
Timely and spatially-regulated injectable hydrogels, able to suppress growing tumors in response to conformational transitions of proteins, are of great interest in cancer research and treatment. ...Herein, we report rapidly responsive silk fibroin (SF) hydrogels formed by a horseradish peroxidase (HRP) crosslinking reaction at physiological conditions, and demonstrate their use as an artificial biomimetic three-dimensional (3D) matrix. The proposed SF hydrogels presented a viscoelastic nature of injectable hydrogels and spontaneous conformational changes from random coil to β-sheet conformation under physiological conditions. A human neuronal glioblastoma (U251) cell line was used for screening cell encapsulation and in vitro evaluation within the SF hydrogels. The transparent random coil SF hydrogels promoted cell viability and proliferation up to 10 days of culturing, while the crystalline SF hydrogels converted into β-sheet structure induced the formation of TUNEL-positive apoptotic cells. Therefore, this work provides a powerful tool for the investigation of the microenvironment on the programed tumor cells death, by using rapidly responsive SF hydrogels as 3D in vitro tumor models.
Culture-independent metagenomic methodologies have enabled detection and identification of microorganisms in various biological systems and often revealed complex and unknown microbiomes. In many ...organisms, the microbiome outnumbers the host cells and greatly affects the host biology and fitness. Ticks are hematophagous ectoparasites with a wide host range. They vector a number of human and animal pathogens and also directly cause major economic losses in livestock. Although several reports on a tick midgut microbiota show a diverse bacterial community, in most cases the size of the bacterial population has not been determined. In this study, the microbiome was quantified in the midgut and ovaries of the ticks
and
before, during, and after blood feeding. Although the size of bacterial community in the midgut fluctuated with blood feeding, it was overall extremely low in comparison to that of other hematophagous arthropods. In addition, the tick ovarian microbiome of both tick species exceeded the midgut 16S rDNA copy numbers by several orders of magnitude. This indicates that the ratio of a tick midgut/ovary microbiome represents an exception to the general biology of other metazoans. In addition to the very low abundance, the tick midgut diversity in
was variable and that is in contrast to that found in the tick ovary. The ovary of
had a very low bacterial diversity and a very high and stable bacterial abundance with the dominant endosymbiont,
sp. The elucidation of this aspect of tick biology highlights a unique tissue-specific microbial-invertebrate host interaction.
Osteoporosis is a public health problem, with bone loss being the main consequence. Hydroxyapatite (HA) has been largely used as a bioceramic to stimulate bone growth. In our work, a ...cerium-containing HA (Ce-HA) has been proposed and its effects on the antimicrobial and bone-inducing properties were investigated. The synthesis of the materials occurred by the suspension–precipitation method (SPM). The XRD (X-ray Diffraction) confirmed the crystalline phase, and the Rietveld refinement confirmed the crystallization of HA and Ce-HA in a hexagonal crystal structure in agreement with ICSD n° 26205. Characterizations by FT-IR (Fourier Transform Infrared Spectroscopy), XPS (X-ray Photoemission Spectroscopy), and FESEM-EDS (Field Emission Scanning Electron Microscope-Energy Dispersive X-ray Spectroscopy) confirmed the presence of cerium (Ce3+ and Ce4+). The antibacterial activity of Has was evaluated against Staphylococcus aureus 25,923 and Escherichia coli 25,922 strains, which revealed that the material has antimicrobial properties and the cytotoxicity assay indicated that Ce-containing HA was classified as non-toxic. The effects of Ce-HA on bone repair, after application in bone defects in the tibia of female rats with osteoporosis induced by ovariectomy (OVX), were evaluated. After 15 and 30 days of implantation, the samples were analyzed by Raman, histology and X-ray microtomography. The results showed that the animals that had the induced bone defects filled with the Ce-HA materials had more expressive bone neoformation than the control group.
Hazard element contamination coming from coal power plants is something obvious, but when this contamination is accompanied by other contamination sources, such as, urban, coal mining and farming ...activities the study gets complicated. This is the case of an area comprised in the southern part of Santa Catarina state (Brazil) with the largest private power plant generator. After the elemental analysis of 41 agricultural soils collected in an extensive area around the thermoelectric (from 0 to 47 km), the high presence of As, Co, Cr, Cu, Fe, Mn, Mo, Pb, Sb, Sn, Tl, V and Zn was found in some specific areas around the power plant. Nevertheless, as the NWAC (Normalized-and-Weighted Average Concentration) confirmed, only soils from one site were classified as of very high concern due to the presence of potential toxic elements. This site was located within the sedimentation basin of the power plant. The spatial distribution obtained by kriging in combination with the analysis of the data by Principal Component Analysis (PCA) revealed three important hotspots in the area according to soil uses and geographic localization: the thermoelectric, its area of influence due to volatile compound deposition, and the area comprised between two urban areas. Farming practice turn out to be an important factor too for the quantity of hazard element stored in soils.
This study aims to demonstrate the applicability and importance of zebrafish (Danio rerio) model to study acute and chronic inflammatory responses induced by different stimuli: carrageenan phlogogen ...(nonimmune); acute infection by bacteria (immune); foreign body reaction (chronic inflammation by round glass coverslip implantation); reaction induced by xenotransplantation. In addition to the advantages of presenting low breeding cost, high prolificity, transparent embryos, high number of individuals belonging to the same spawning and high genetic similarity that favor translational responses to vertebrate organisms like humans, zebrafish proved to be an excellent tool, allowing the evaluation of edema formation, accumulation of inflammatory cells in the exudate, mediators, signaling pathways, gene expression and production of specific proteins. Our studies demonstrated the versatility of fish models to investigate the inflammatory response and its pathophysiology, essential for the successful development of studies to discover innovative pharmacological strategies.
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