666 research outputs found
Trichothecenes NIV and DON modulate the maturation of murinedendritic cells
Nivalenol (NIV) and Deoxynivalenol (DON), mycotoxins of the trichothecene family are considered very common food contaminants. In this work, we investigated whether the immunotoxic effects ascribed to these trichothecenes may be mediated by perturbations in the activity of dendritic cells (DCs). Murine bone marrow-derived DCs were used to evaluate the effects of NIV and DON on the LPS-induced maturation process.We found that the expression of the class II MHC and of the accessory CD11c molecules, but not of the costimulatory CD86 marker, was down-regulated by NIV and DON exposure in LPS-treated DCs, as well as nitric oxide (NO) production. Interestingly, NIV, but not DON, induced DC necrosis. Moreover, the analysis of the cytokine pattern showed that IL-12 and IL-10 expressions induced by LPS exposure were suppressed by both trichothecenes in a dose-dependent fashion. On the other hand, the secretion of the proinflammatory cytokine TNFa was increased as a direct consequence of DON and NIV exposure. Taken together, our data indicated that the immunotoxicity of NIV and DON was related to the capacity of both trichothecenes to interfere with phenotypic and functional features of maturing DCs
Mycotoxins nivalenol and deoxynivalenol differently modulate cytokine mRNA expression in Jurkat T cells.
Deoxynivalenol (DON) and its hydroxylated form nivalenol (NIV) are Fusarium mycotoxins that occur in cereal grains alone or in
combination. Several studies have shown that these metabolites affect lymphocyte functions. However, the molecular mechanisms
underlying their activities are still partially known. To address this issue, we examined the influence of NIV and DON in modulating
IFNc, IL-2 and IL-8 mRNA levels in Jurkat T cells. In PMA/ionomycin stimulated cells, pre-incubated with increasing concentrations of NIV, transcription was induced in the range 0.06â2 lM; higher concentrations of NIV were found non-stimulating (4 lM) or inhibitory (8 lM) for IFNc and IL-2 whereas IL-8 was still induced. DON administration elicited a similar profile for IL-8 and IFNc, whilst IL-2 mRNA was induced in a broader range of concentrations. Combination of NIV and DON at 1:1 and 1:10 ratios essentially restored the cytokine transcriptional pattern observed with NIV alone but the level of transcripts, with the exception of IL-8, peaked at lower concentrations suggesting interactive effects. Moreover both mycotoxins caused inhibition of cell proliferation, mediated by induction of apoptosis, confirming previous results and highlighting the usefulness of Jurkat as a T-cell model to study the effects of mycotoxins on the immune functions in humans
SEISMIC CHARACTERIZATION OF SHALLOW BEDROCK SITES WITH MULTIMODAL MONTECARLO INVERSION OF SURFACE WAVEDATA
Seismic characterization of shallow bedrock sites with multi-modal Monte Carlo inversion of surface wave data
Biological Properties of IRIM, the Iridium(III) Analogue of (Imidazolium (Bisimidazole) Tetrachlororuthenate) (ICR)
Some biological aspects of the new complex imidazolium bisimidazole tetrachloro iridate(III)-IRIM- the iridium(III) analogue of ICR, were considered. More in detail the conformational effects produced by IRIM on DNA and the cytotoxic properties of IRIM on some selected human cell lines were measured.
Dialysis experiments and DNA thermal denaturation studies are suggestive of poor binding of IRIM to DNA;
formation of interstrand crosslinks is not observed. In any case CD measurements suggest that addition of
increasing amounts of IRIM to calf thymus DNA results into significant spectral changes, that are diagnostic
of a direct interaction with DNA. A number of experiments carried out on the A2780 human ovarian carcinoma,
B16 murine melanoma, MCF7 and TS mammary adenocarcinoma tumor cell lines strongly point out
that IRIM does not exhibit significant growth inhibition effects within the concentration range 10-4-10-6 M. It
is suggested that the lower biological effects of IRIM compared to ICR are a consequence of the larger kinetic
inertness of the iridium(III) center with respect to ruthenium(III)
Co-targeting of Bcl-2 and mTOR pathway triggers synergistic apoptosis in BH3 mimetics resistant acute lymphoblastic leukemia
Several chemo-resistance mechanisms including the Bcl-2 protein family overexpression and constitutive activation of the PI3K/Akt/mTOR signaling have been documented in acute lymphoblastic leukemia (ALL), encouraging targeted approaches to circumvent this clinical problem. Here we analyzed the activity of the BH3 mimetic ABT-737 in ALL, exploring the synergistic effects with the mTOR inhibitor CCI-779 on ABT-737 resistant cells. We showed that a low Mcl-1/Bcl-2 plus Bcl-xL protein ratio determined ABT-737 responsiveness. ABT-737 exposure further decreased Mcl-1, inducing apoptosis on sensitive models and primary samples, while not affecting resistant cells. Co-inhibition of Bcl-2 and the mTOR pathway resulted cytotoxic on ABT-737 resistant models, by downregulating mTORC1 activity and Mcl-1 in a proteasome-independent manner. Although Mcl-1 seemed to be critical, ectopic modulation did not correlate with apoptosis changes. Importantly, dual targeting proved effective on ABT-737 resistant samples, showing additive/synergistic effects. Together, our results show the efficacy of BH3 mimetics as single agent in the majority of the ALL samples and demonstrate that resistance to ABT-737 mostly correlated with Mcl-1 overexpression. Co-targeting of the Bcl-2 protein family and mTOR pathway enhanced drug-induced cytotoxicity by suppressing Mcl-1, providing a novel therapeutic approach to overcome BH3 mimetics resistance in ALL
Assessing climate effects on railway earthworks Using MASW
Many parts of the UKâs rail network were constructed in the midâ19th century long before the advent of
modern construction standards. Historic levels of low investment, poor maintenance strategies and the
deleterious effects of climate change have resulted in critical elements of the rail network being at
significant risk of failure. The majority of failures which have occurred over recent years have been
triggered by extreme weather events. Advance assessment and remediation of earthworks is, however,
significantly less costly than dealing with failures reactively. It is therefore crucial that appropriate approaches
for assessment of the stability of earthworks are developed, so that repair work can be better targeted and
failures avoided wherever possible. This extended abstract briefly discusses some preliminary results from an
ongoing geophysical research project being carried out in order to study the impact of climate or seasonal
weather variations on the stability of a century old railway embankment on the Gloucestershire Warwickshire
steam railway line in Southern England
Multidrug-resistant Candida glabrata strains obtained by induction of anidulafungin resistance in planktonic and biofilm cells
Candida glabrata has emerged as a common cause of serious life-threatening fungal infections, largely owing to their low susceptibility to azole antifungals. Recent guidance indicates the use of echinocandins as the first-choice drug for the treatment of systemic infections of C. glabrata; however, C. glabrata resistance to echinocandins is reportedly increasing. Herein, we present the induction of anidulafungin resistance in planktonic and sessile cells of C. glabrata and the development of fluconazole crossresistance. MICs of 21 clinical C. glabrata strains were determined by a broth microdilution method using anidulafungin and fluconazole. Biofilm formation on a tracheal catheter was determined using 1- Ă 1-cm2 polyvinyl polychloride catheter fragments. Induction of anidulafungin resistance in planktonic and sessile cells and evaluation of its stability were performed by exposing the strains to successively higher concentrations of the antifungal. The induction resulted in strains strongly resistant to anidulafungin (MICs: 1â2 ÎŒg/mL) and fluconazole (â„64 ÎŒg/mL). Most of the sessile cells of C. glabrata presented slightly reduced susceptibility compared with the planktonic cells. Clinically, this cross-resistance could lead to therapeutic failure while using fluconazole in patients previously exposed to subinhibitory concentrations of anidulafungin for extended periods
On distributed strains in a CFA pile via DFOSs measurements and numerical analysis
Fibre Optic Sensors (FOSs) offer unprecedented possibilities for the monitoring of engineering structures, such as foundation systems. Notably, the type of FOSs known as Distributed Fibre Optic Sensors (DFOSs) has the capability of monitoring variations in the observed physical field, such as strain and temperature, with spatial continuity along the fibre. This paper presents and discusses the distributed strain measurements collected along a continuous flight auger (CFA) pile, belonging to the foundation raft of a new bridge subjected to an acceptance static load test. The monitoring was performed using a DFOS system, which works according to the optical frequency domain reflectometry (OFDR) method and provides a spatial resolution of 10 mm and a strain resolution of 1 \u3bc\u3b5. The in-situ monitoring results were used to calibrate a 3D Finite Element Model of the foundation system. The soil properties for the numerical model were also selected on the basis of a load test previously carried out on a similar pile at the same sit
Lysozyme-induced transcriptional regulation of tnf-\u3b1 pathway genes in cells of the monocyte lineage
Lysozyme is one of the most important anti-bacterial effectors in the innate immune system of animals. Besides its direct antibacterial enzymatic activity, lysozyme displays other biological properties, pointing toward a significant anti-inflammatory effect, many aspects of which are still elusive. Here we investigate the perturbation of gene expression profiles induced by lysozyme in a monocyte cell line in vitro considering a perspective as broad as the whole transcriptome profiling. The results of the RNA-seq experiment show that lysozyme induces transcriptional modulation of the TNF-\u3b1/IL-1\u3b2 pathway genes in U937 monocytes. The analysis of transcriptomic profiles with IPA\uae identified a simple but robust molecular network of genes, in which the regulation trends are fully consistent with the anti-inflammatory activity of lysozyme. This study provides the first evidence in support of the anti-inflammatory action of lysozyme on the basis of transcriptomic regulation data resulting from the broad perspective of a whole-transcriptome profiling. Such important effects can be achieved with the supplementation of relatively low concentrations of lysozyme, for a short time of exposure. These new insights allow the potential of lysozyme in pharmacological applications to be better exploited
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