Dihydrotanshinone,a Natural Diterpenoid,Preserves Blood-Retinal Barrier Integrity via P2X7 Receptor

Activation of P2X7 signaling, due to high glucose levels, leads to blood retinal barrier (BRB) breakdown, which is a hallmark of diabetic retinopathy (DR). Furthermore, several studies report that high glucose (HG) conditions and the related activation of the P2X7 receptor (P2X7R) lead to the over-expression of pro-inflammatory markers. In order to identify novel P2X7R antagonists, we carried out virtual screening on a focused compound dataset, including indole derivatives and natural compounds such as caffeic acid phenethyl ester derivatives, flavonoids, and diterpenoids. Molecular Mechanics/Generalized Born Surface Area (MM/GBSA) rescoring and structural fingerprint clustering of docking poses from virtual screening highlighted that the diterpenoid dihydrotanshinone (DHTS) clustered with the well-known P2X7R antagonist JNJ47965567. A human-based in vitro BRB model made of retinal pericytes, astrocytes, and endothelial cells was used to assess the potential protective effect of DHTS against HG and 2′(3′)-O-(4-Benzoylbenzoyl)adenosine-5′-triphosphate (BzATP), a P2X7R agonist, insult. We found that HG/BzATP exposure generated BRB breakdown by enhancing barrier permeability (trans-endothelial electrical resistance (TEER)) and reducing the levels of ZO-1 and VE-cadherin junction proteins as well as of the Cx-43 mRNA expression levels. Furthermore, HG levels and P2X7R agonist treatment led to increased expression of pro-inflammatory mediators (TLR-4, IL-1β, IL-6, TNF-α, and IL-8) and other molecular markers (P2X7R, VEGF-A, and ICAM-1), along with enhanced production of reactive oxygen species. Treatment with DHTS preserved the BRB integrity from HG/BzATP damage. The protective effects of DHTS were also compared to the validated P2X7R antagonist, JNJ47965567. In conclusion, we provided new findings pointing out the therapeutic potential of DHTS, which is an inhibitor of P2X7R, in terms of preventing and/or counteracting the BRB dysfunctions elicited by HG conditions.     

Neuroprotective Effects of Testosterone in the Hypothalamus of an Animal Model of Metabolic Syndrome

Metabolic syndrome (MetS) is known to be associated to inflammation and alteration in the hypothalamus, a brain region implicated in the control of several physiological functions, including energy homeostasis and reproduction. Previous studies demonstrated the beneficial effects of testosterone treatment (TTh) in counteracting some MetS symptoms in both animal models and clinical studies. This study investigated the effect of TTh (30 mg/kg/week for 12 weeks) on the hypothalamus in a high-fat diet (HFD)-induced animal model of MetS, utilizing quantitative RT-PCR and immunohistochemical analyses. The animal model recapitulates the human MetS features, including low testosterone/gonadotropin plasma levels. TTh significantly improved MetS-induced hypertension, visceral adipose tissue accumulation, and glucose homeostasis derangements. Within hypothalamus, TTh significantly counteracted HFD-induced inflammation, as detected in terms of expression of inflammatory markers and microglial activation. Moreover, TTh remarkably reverted the HFD-associated alterations in the expression of important regulators of energy status and reproduction, such as the melanocortin and the GnRH-controlling network. Our results suggest that TTh may exert neuroprotective effects on the HFD-related hypothalamic alterations, with positive outcomes on the circuits implicated in the control of energy metabolism and reproductive tasks, thus supporting a possible role of TTh in the clinical management of MetS.     

The AFLATOX® Project: Approaching the Development of New Generation,Natural-Based Compounds for the Containment of the Mycotoxigenic Phytopathogen Aspergillus flavus and Aflatoxin Contamination

The control of the fungal contamination on crops is considered a priority by the sanitary authorities of an increasing number of countries, and this is also due to the fact that the geographic areas interested in mycotoxin outbreaks are widening. Among the different pre- and post-harvest strategies that may be applied to prevent fungal and/or aflatoxin contamination, fungicides still play a prominent role; however, despite of countless efforts, to date the problem of food and feed contamination remains unsolved, since the essential factors that affect aflatoxins production are various and hardly to handle as a whole. In this scenario, the exploitation of bioactive natural sources to obtain new agents presenting novel mechanisms of action may represent a successful strategy to minimize, at the same time, aflatoxin contamination and the use of toxic pesticides. The Aflatox^® Project was aimed at the development of new-generation inhibitors of aflatoxigenic Aspergillus spp. proliferation and toxin production, through the modification of naturally occurring molecules: a panel of 177 compounds, belonging to the thiosemicarbazones class, have been synthesized and screened for their antifungal and anti-aflatoxigenic potential. The most effective compounds, selected as the best candidates as aflatoxin containment agents, were also evaluated in terms of cytotoxicity, genotoxicity and epi-genotoxicity to exclude potential harmful effect on the human health, the plants on which fungi grow and the whole ecosystem.     

Enzymatic hydrolysis of cotton wastes. Effect of γ-ray pretreatments

Textile cotton wastes were irradiated with γ-rays at different doses and solubilized with 10% NaOH solutions. The regenerated products underwent enzymatic hydrolysis and their degradation pattern was compared with that of the cotton celluloses untreated or treated only with γ-rays. The different samples were characterized by measurements of X-ray diffraction, degree of polymerization, moisture regain and water retention. The structural and morphological modifications induced by the pretreatments were correlated with the variations of kinetic parameters, particularly the V_max/K_m ratio, defined as specificity constant. Only the combination of irradiation with dissolution pretreatments gave a considerable increase of hydrolysis reaction effectiveness.     

Time‐multiplexed tiled projection system with improved pixel and spatial resolution

We propose two methods to increase the pixel and spatial resolution of Digital Micromirror Devices (DMD)‐based projectors by utilizing the large bandwidth provided by their high pattern rates. By varying the intensity of the illumination for each binary pattern displayed on the DMD, the time required to display an 8‐bit grayscale image can be reduced by up to factor 32 compared to using constant illumination and binary pulse‐width modulation (BPWM). The high image rate projection is then spatially separated by either using a galvanometer scanner or sequentially illuminating the DMD from different directions, thus creating multiple independently addressable projections which are then tiled to form a larger, higher resolution image.     

On the human ability to discriminate audio ambiances from similar locations of an urban environment

When developing advanced location-based systems augmented with audio ambiances, it would be cost-effective to use a few representative samples from typical environments for describing a larger number of similar locations. The aim of this experiment was to study the human ability to discriminate audio ambiances recorded in similar locations of the same urban environment. A listening experiment consisting of material from three different environments and nine different locations was carried out with nineteen subjects to study the credibility of audio representations for certain environments which would diminish the need for collecting huge audio databases. The first goal was to study to what degree humans are able to recognize whether the recording has been made in an indicated location or in another similar location, when presented with the name of the place, location on a map, and the associated audio ambiance. The second goal was to study whether the ability to discriminate audio ambiances from different locations is affected by a visual cue, by presenting additional information in form of a photograph of the suggested location. The results indicate that audio ambiances from similar urban areas of the same city differ enough so that it is not acceptable to use a single recording as ambience to represent different yet similar locations. Including an image was found to increase the perceived credibility of all the audio samples in representing a certain location. The results suggest that developers of audio-augmented location-based systems should aim at using audio samples recorded on-site for each location in order to achieve a credible impression.     

High-efficiency, argon-laser-pumped Nd:YLF laser system

An Ar-ion laser was used to pump a Nd:YLF laser, in both σ and π polarizations, in a longitudinal scheme. In spite of the small absorption coefficient at the pump (~0.25 cm (-1)), a careful laser design can circumvent this problem, and efficiencies as high as those attained with semiconductor pumping schemes are reported. The laser fundamental parameters were experimentally determined. A double-pass net gain as high as 10(3) was measured, and an output power of 1 W was obtained with a pumping power of 6 W.     

A data fusion and spatial data analysis approach for the estimation of wheat grain nitrogen uptake from satellite data

The selection of the optimal band combination for the estimation of specific crop variables is a key aspect in order to obtain reliable estimation of in-field variability from multi- and hyperspectral remote-sensing data. The selection of the bands is strongly influenced by the phenological stage of the crop at the acquisition time. In this work, the influence of the growing stage on the combination of spectral bands related to grain nitrogen (N) uptake in wheat was evaluated using multispectral (Satellite Pour l’Observation de la Terre – SPOT) and hyperspectral (Compact High Resolution Imaging Spectrometer – CHRIS-PROBA) satellite images at different growth stages over two wheat growth seasons in central Italy. In order to identify the more appropriate covariates (spectral bands) for each phenological stage, stepwise regression with backward selection was combined with stepwise variance inflation factors (VIFs) analysis and linear mixed effect model (LMEM). The results obtained in this study suggest that the spectral region most related to N uptake varies over the growing season of the wheat crop. For SPOT data, near-infrared (NIR) region was selected at all the phenological stages in both growing seasons, except for the latest stage, with low chlorophyll content due to the onset of senescence, in which the red band was selected. At stem elongation, the shortwave infrared (SWIR) band of SPOT data was also selected. At this stage, the best N estimation accuracy was obtained using an LMEM (root mean square error, RMSE = 0.012 t ha^?1). The inclusion of a spatial component in the estimation model by means of LMEMs provided a more accurate estimation than ordinary least square (OLS) models at all growth stages. The test carried out with CHRIS-PROBA data at the fourth stage confirmed the importance of NIR and in particular of the red-edge region for N uptake prediction. A novel methodology is proposed, which involves two crucial aspects in the context of the use of remote-sensing data in precision agriculture: i) the standardization of the spatial resolution for in-field and satellite data by a geostatistical data technique (data fusion); and ii) the selection of the most appropriate spectral bands for each phenological stage, taking into account both correlation with the target variable and collinearity.     

Proteins as biomarkers of oxidative/nitrosative stress in diseases: the contribution of redox proteomics

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) contribute to the pathogenesis and/or progression of several human diseases. Proteins are important molecular signposts of oxidative/nitrosative damage. However, it is generally unresolved whether the presence of oxidatively/nitrosatively modified proteins has a causal role or simply reflects secondary epiphenomena. Only direct identification and characterization of the modified protein(s) in a given pathophysiological condition can decipher the potential roles played by ROS/RNS-induced protein modifications. During the last few years, mass spectrometry (MS)-based technologies have contributed in a significant way to foster a better understanding of disease processes. The study of oxidative/nitrosative modifications, investigated by redox proteomics, is contributing to establish a relationship between pathological hallmarks of disease and protein structural and functional abnormalities. MS-based technologies promise a contribution in a new era of molecular medicine, especially in the discovery of diagnostic biomarkers of oxidative/nitrosative stress, enabling early detection of diseases. Indeed, identification and characterization of oxidatively/nitrosatively modified proteins in human diseases has just begun.