A hybrid calibration-free/artificial neural networks approach to the quantitative analysis of LIBS spectra

A 'hybrid' method is proposed for the quantitative analysis of materials by LIBS, combining the precision of the calibration-free LIBS (CF-LIBS) algorithm with the quickness of artificial neural networks. The method allows the precise determination of the samples' composition even in the presence of relatively large laser fluctuations and matrix effects. To show the strength and robustness of this approach, a number of synthetic LIBS spectra of Cu-Ni binary alloys with different composition were computer-simulated, in correspondence of different plasma temperatures, electron number densities and ablated mass. The CFLIBS/ANN approach here proposed demonstrated to be capable, after appropriate training, of 'learning' the basic physical relations between the experimentally measured line intensities and the plasma parameters. Because of that the composition of the sample can be correctly determined, as in CF-LIBS measurements, but in a much shorter time

An artificial neural network approach to laser-induced breakdown spectroscopy quantitative analysis

The usual approach to laser-induced breakdown spectroscopy (LIBS) quantitative analysis is based on the use of calibration curves, suitably built using appropriate reference standards. More recently, statistical methods relying on the principles of artificial neural networks (ANN) are increasingly used. However, ANN analysis is often used as a 'black box' system and the peculiarities of the LIBS spectra are not exploited fully. An a priori exploration of the raw data contained in the LIBS spectra, carried out by a neural network to learn what are the significant areas of the spectrum to be used for a subsequent neural network delegated to the calibration, is able to throw light upon important information initially unknown, although already contained within the spectrum. This communication will demonstrate that an approach based on neural networks specially taylored for dealing with LIBS spectra would provide a viable, fast and robust method for LIBS quantitative analysis. This would allow the use of a relatively limited number of reference samples for the training of the network, with respect to the current approaches, and provide a fully automatizable approach for the analysis of a large number of samples

Gene transfer of a soluble IL-1 type 2 receptor-Ig fusion protein improves cardiac allograft survival in rats

Objective: Interleukin-1 (IL-1) mediates ischemia-reperfusion injury and graft inflammation after heart transplantation. IL-1 affects target cells through two distinct types of transmembrane receptors, type-1 receptor (IL-1R1), which transduces the signal, and the non-signaling type-2 receptor (IL-1R2), which acts as a ligand sink that subtracts IL-1β from IL-1R1. We analyzed the efficacy of adenovirus (Ad)-mediated gene transfer of a soluble IL-1R2-Ig fusion protein in delaying cardiac allograft rejection and the mechanisms underlying the protective effect. Methods: IL-1 inhibition by IL-1R2-Ig was tested using an in vitro functional assay whereby endothelial cells preincubated with AdIL-1R2-Ig or control virus were stimulated with recombinant IL-1β or tumor necrosis factor-α (TNF-α), and urokinase-type plasminogen activator (u-PA) induction was measured by zymography. AdIL-1R2-Ig was delivered to F344 rat donor hearts ex vivo, which were placed in the abdominal position in LEW hosts. Intragraft inflammatory cell infiltrates and proinflammatory cytokine expression were analyzed by immunohistochemistry and real-time reverse transcriptase-polymerase chain reaction (RT-PCR), respectively. Results: IL-1R2-Ig specifically inhibited IL-1β-induced u-PA responses in vitro. IL-1R2-Ig gene transfer reduced intragraft monocytes/macrophages and CD4+ cell infiltrates (p≪0.05), TNF-α and transforming growth factor-β (TGF-β) expression (p≪0.05), and prolonged graft survival (15.6±5.7 vs 10.3±2.5 days with control vector and 10.1±2.1 days with buffer alone; p≪0.01). AdIL-1R2-Ig combined with a subtherapeutic regimen of cyclosporin A (CsA) was superior to CsA alone (19.4±3.0 vs 15.9±1.8 days; p≪0.05). Conclusions: Soluble IL-1 type-2 receptor gene transfer attenuates cardiac allograft rejection in a rat model. IL-1 inhibition may be useful as an adjuvant therapy in heart transplantatio

Effect of bioactive compounds released from Brassicaceae defatted seed meals on bacterial load in pig manure.

Animal manure application to soils is considered to be one of the main cause of antibiotic and bacterial pathogen spread in the environment. Pig livestock, which is the source of one of the most used fertilizer for cultivated land, is also a hotspot for antibiotics and antibiotic-resistant bacteria. Besides harsh chemical and physical sanitization treatments for the abatement of antibiotics and bacterial load in livestock waste, more sustainable and environmentally friendly strategies need to be considered. In this context, the use of natural substances which are proved useful for pest and disease control is currently under exploration for their role in the reduction of bacterial pathogen population. Among these, plants and derived products from the Brassicaceae family, characterized by the presence of a defensive glucosinolate-myrosinase enzymatic system, have been successfully exploited for years in agriculture using the so-called biofumigation technique against crop diseases. Although the application of biofumigation to suppress a range of soil borne pests has been well documented, no studies have been examined to reduce bacterial population in animal waste. In the present study, the release and the antibacterial activity of bioactive compounds deriving from different Brassicaceae defatted seed meals against pathogens and bacterial population in pig manure is addressed. Rapistrum rugosum and Brassica nigra defatted seed meals were found to be the most active products against tested pathogens and able to significantly reduce the bacterial load in the manure

Anti-Inflammatory Effect of the Natural H2S-Donor Erucin in Vascular Endothelium

Vascular inflammation (VI) represents a pathological condition that progressively affects the integrity and functionality of the vascular wall, thus leading to endothelial dysfunction and the onset of several cardiovascular diseases. Therefore, the research of novel compounds able to prevent VI represents a compelling need. In this study, we tested erucin, the natural isothiocyanate H2S-donor derived from Eruca sativa Mill. (Brassicaceae), in an in vivo mouse model of lipopolysaccharide (LPS)-induced peritonitis, where it significantly reduced the amount of emigrated CD11b positive neutrophils. We then evaluated the anti-inflammatory effects of erucin in LPS-challenged human umbilical vein endothelial cells (HUVECs). The pre-incubation of erucin, before LPS treatment (1, 6, 24 h), significantly preserved cell viability and prevented the increase of reactive oxygen species (ROS) and tumor necrosis factor alpha (TNF-alpha) levels. Moreover, erucin downregulated endothelial hyperpermeability and reduced the loss of vascular endothelial (VE)-Cadherin levels. In addition, erucin decreased vascular cell adhesion molecule 1 (VCAM-1), cyclooxygenase-2 (COX-2) and microsomal prostaglandin E-synthase 1 (mPGES-1) expression. Of note, erucin induced eNOS phosphorylation and counteracted LPS-mediated NF-kappa B nuclear translocation, an effect that was partially abolished in the presence of the eNOS inhibitor L-NAME. Therefore, erucin can control endothelial function through biochemical and genomic positive effects against VI

Bioactive Compounds from Eruca sativa Seeds

Eruca sativa Miller (Brassicaceae) is an insect-pollinated diploid annual species which grows spontaneously in the entire Mediterranean basin from semi-arid to arid-hot conditions and is cultivated in Northern America, Europe, and Asia as either salad or oilseed crop. Here, some essential background was provided on this versatile crop, summarizing the present status of Eruca sativa research focusing on the wealth of bioactive ingredients in its seeds, which may find exploitation in agriculture, in the food industries and as nutraceuticals for their antioxidant and anti-inflammatory properties. Fatty acids of Eruca sativa seed oil, gums, glucosinolates and soluble and insoluble phenol and flavonoid fractions in the defatted press cake are the main bioactive compounds considered to date by the scientific literature and that deserve attention for their physical and biological activities

Bioactive Compounds from <i>Eruca sativa</i> Seeds

Eruca sativa Miller (Brassicaceae) is an insect-pollinated diploid annual species which grows spontaneously in the entire Mediterranean basin from semi-arid to arid-hot conditions and is cultivated in Northern America, Europe, and Asia as either salad or oilseed crop. Here, some essential background was provided on this versatile crop, summarizing the present status of Eruca sativa research focusing on the wealth of bioactive ingredients in its seeds, which may find exploitation in agriculture, in the food industries and as nutraceuticals for their antioxidant and anti-inflammatory properties. Fatty acids of Eruca sativa seed oil, gums, glucosinolates and soluble and insoluble phenol and flavonoid fractions in the defatted press cake are the main bioactive compounds considered to date by the scientific literature and that deserve attention for their physical and biological activities

IDENTIFICATION OF HISTONE MODIFICATIONS INVOLVED IN HDAC1 INHIBITION BY 9-HSA

9-hydroxystearic acid (9-HSA) is a product of endogenous lipoperoxidation identified in several human cell lines; its administration to HT29, a colon adenocarcinoma cell line, causes growth arrest in G0/G1 and differentiation toward a benign phenotype. The relevant molecular events are the increased transcription of p21WAF1, TGFbeta1, alkaline phosphatase, and subunit alfa5 of integrin. The number of genes whose activity is modified is indeed rather restricted: in particular variations of the activity of genes that regulate the cell cycle, apoptosis and differentiation have been evidenced for several HDAC1 inhibitors, but the mechanisms that induce or repress the selective activation of genes, beginning from the acetylation state of chromatin or of nuclear proteins, are not yet clear. In HT29, both histones H3 and H4 appear to be hyperacetylated as a consequence of 9-HSA administration. The isolation of histones, the identification of their isoforms as well as the determination of their modifications are essential steps of our study. Reverse phase, ion exchange or hydrophylic-interaction liquid chromatography and subsequent identification of each fraction by electrophoresis or mass spectrometry have become urepleaceble approaches for the analysis of protein modification sites. This work proposes an experimental approach for studying the different isoforms through the injection of the mixture of histones, extracted and solubilized in water, in a liquid chromatograph Jasco PU-1585 equipped with a Rheodyne Model 7725i injector, connected to a UV (JascoUV-1575) detector and to a LCQDuo (Thermo Finnigan) mass spectrometer, that is in turn interfaced to an electrospray ionization source (ESI), and equipped with an ion trap analyzer. The analysis of the peaks so obtained has been carried out by employing deconvolution programs that allow the determination of the MW of proteins and characterize and quantify also the acetylated and methylated isoforms

Biocontrol of Monilinia laxa by Aureobasidium pullulans strains: Insights on competition for nutrients and space

Two Aureobasidium pullulans strains (L1 and L8), able to prevent postharvest fruit decay, were evaluated in order to elucidate how the competition for nutrients and space was involved in their activity against Monilinia laxa, the causal agent of peach brown rot. The competition for nutrients was studied by co-culturing pathogen conidia and antagonists in different conditions of nutrient availability and avoiding contact between them. Both antagonists prevented the germination of conidia of M. laxa in water, reducing germination rate by > 35%. However, L1 and L8 showed the lowest inhibition of conidial germination in peach juice at 5%, with a reduction of 12.6% and 13.9% respectively. HPLC amino acid analysis of peach juice revealed that the addition of the yeast suspension greatly modified their composition: asparagine was completely depleted soon after 12 h of incubation and was probably hydrolyzed to aspartic acid by the yeasts, as aspartic acid content markedly increased. Pure asparagine and aspartic acid were tested by in vitro trials at the concentrations found in peach juice: both influenced M. laxa growth, but in opposite ways. Asparagine stimulated pathogen growth; conversely, amended medium with aspartic acid significantly inhibited the conidia germination and mycelial development of M. laxa. Scanning Electron Microscopy revealed that both strains showed a great capability to compete with M. laxa for space (starting 8 h after treatment), colonizing the wound surface and inhibiting pathogen growth. This study clearly showed that A. pullulans L1 and L8 strains could compete with M. laxa for nutrients and space; this mode of action may play an important role in the antagonistic activity, especially in the first hours of tritrophic host-pathogen-antagonist interaction, although several other mechanisms can interact each other