Upregulation of inducible NO synthase by exogenous adenosine in vascular smooth muscle cells activated by inflammatory stimuli in experimental diabetes

BACKGROUND: Adenosine has been shown to induce nitric oxide (NO) production via inducible NO synthase (iNOS) activation in vascular smooth muscle cells (VSMCs). Although this is interpreted as a beneficial vasodilating pathway in vaso-occlusive disorders, iNOS is also involved in diabetic vascular dysfunction. Because the turnover of and the potential to modulate iNOS by adenosine in experimental diabetes have not been explored, we hypothesized that both the adenosine system and control of iNOS function are impaired in VSMCs from streptozotocin-diabetic rats. METHODS: Male Sprague-Dawley rats were injected with streptozotocin once to induce diabetes. Aortic VSMCs from diabetic and nondiabetic rats were isolated, cultured and exposed to lipopolysaccharide (LPS) plus a cytokine mix for 24 h in the presence or absence of (1) exogenous adenosine and related compounds, and/or (2) pharmacological agents affecting adenosine turnover. iNOS functional expression was determined by immunoblotting and NO metabolite assays. Concentrations of adenosine, related compounds and metabolites thereof were assayed by HPLC. Vasomotor responses to adenosine were determined in endothelium-deprived aortic rings. RESULTS: Treatment with adenosine-degrading enzymes or receptor antagonists increased iNOS formation in activated VSMCs from nondiabetic and diabetic rats. Following treatment with the adenosine transport inhibitor NBTI, iNOS levels increased in nondiabetic but decreased in diabetic VSMCs. The amount of secreted NO metabolites was uncoupled from iNOS levels in diabetic VSMCs. Addition of high concentrations of adenosine and its precursors or analogues enhanced iNOS formation solely in diabetic VSMCs. Exogenous adenosine and AMP were completely removed from the culture medium and converted into metabolites. A tendency towards elevated inosine generation was observed in diabetic VSMCs, which were also less sensitive to CD73 inhibition, but inosine supplementation did not affect iNOS levels. Pharmacological inhibition of NOS abolished adenosine-induced vasorelaxation in aortic tissues from diabetic but not nondiabetic animals. CONCLUSIONS: Endogenous adenosine prevented cytokine- and LPS-induced iNOS activation in VSMCs. By contrast, supplementation with adenosine and its precursors or analogues enhanced iNOS levels in diabetic VSMCs. This effect was associated with alterations in exogenous adenosine turnover. Thus, overactivation of the adenosine system may foster iNOS-mediated diabetic vascular dysfunction

Giant reed (Arundo donax L.) as energy crop in Central Italy: A review

In the European Union energy security have been driving the search for economically viable and environmentally sustainable renewable energy sources since the 90’s. Energy crops could represent a good opportunity to combine the energy goals with the conservation of farmer incomes and the global climate change control. Giant reed (Arundo donax L.) is a perennial rhizomatous grass particularly attractive for energy production because of a high yield potential, a generally positive environmental impact and a good attitude to energy conversion. Long-term studies carried out in Central Italy confirmed its high production level, in both fertile and marginal lands (aboveground yields from 38 to 20 t ha–1 year–1). In addition, the crop highlighted a high growth rate at the beginning of the growing season, progressively decreasing in summer when high temperature and low water availability occurred. Giant reed nutrient requirements were generally low and part of nutrient stocks were remobilized from the rhizome to the aboveground biomass over the spring, with the opposite flow occurring in autumn. From an environmental point of view giant reed showed a positive energy balance with a high-energy efficiency. Compared to other energy crops, giant reed showed the lowest GHG emissions per unit of energy and the best performance in terms of cost per ton of dry biomass or per unit of energy. To improve knowledge on giant reed and to favour the diffusion of energy crops in Italian cropping systems, further studies are needed to analyze the long-term effects of giant reed on soil fertility and the optimal soil management after its cultivation. In our researches the environmental impacts of giant reed and its production costs were referred to the production phase. Therefore, there is the need to extend the research activity to the whole energy chain and to identify the most sustainable conversion technologies (e.g. biogas, 2nd generation bioethanol, etc.) for the different environments

Lo sviluppo di un sistema di gestione del verde urbano mediante l'utilizzo di un software WebGIS Open Source. La riduzione della spesa pubblica come stimolo per cercare di mantenere e migliorare il livello dei servizi a tutto vantaggio per i cittadini europei.

La scelta di una pubblica amministrazione di sviluppare, migliorare o semplicemente mantenere un servizio, oggi deve fare i conti con una riduzione di risorse economiche anche considerevoli. L'approccio a un sistema realmente collaborativo, l'utilizzo di risorse disponibili, l'integrazione dei dati laddove necessari, potrebbe permettere di avere uno strumento altrettanto valido per la gestione grafica delle informazioni. Pur non rappresentando una novità, l'aver lavorato al problema della gestione del verde urbano ha rappresentato l'occasione per poter mostrare la versatilità di un sistema, ipotizzandone possibili ulteriori sviluppi futuri. I limiti che ci siamo dati sono stati quelli di : utilizzare strumenti disponibili, limitare i costi al minimo, ottenere un risultato utile e valido sia per l'Ente Gestore che per gli utenti finali ed infine migliorare il livello di servizio. Alcuni software open source disponibili ci hanno aiutato in questo compito, ciò non toglie la possibilità di scegliere ed utilizzare altri prodotti commerciali dedicati e specifici.JRC.C.4-Maintenance and Utilitie

Corticocortical feedback increases the spatial extent of normalization

Normalization has been proposed as a canonical computation operating across different brain regions, sensory modalities, and species. It provides a good phenomenological description of non-linear response properties in primary visual cortex (V1), including the contrast response function and surround suppression. Despite its widespread application throughout the visual system, the underlying neural mechanisms remain largely unknown. We recently observed that corticocortical feedback contributes to surround suppression in V1, raising the possibility that feedback acts through normalization. To test this idea, we characterized area summation and contrast response properties in V1 with and without feedback from V2 and V3 in alert macaques and applied a standard normalization model to the data. Area summation properties were well explained by a form of divisive normalization, which computes the ratio between a neuron's driving input and the spatially integrated activity of a “normalization pool.” Feedback inactivation reduced surround suppression by shrinking the spatial extent of the normalization pool. This effect was independent of the gain modulation thought to mediate the influence of contrast on area summation, which remained intact during feedback inactivation. Contrast sensitivity within the receptive field center was also unaffected by feedback inactivation, providing further evidence that feedback participates in normalization independent of the circuit mechanisms involved in modulating contrast gain and saturation. These results suggest that corticocortical feedback contributes to surround suppression by increasing the visuotopic extent of normalization and, via this mechanism, feedback can play a critical role in contextual information processing

Aboveground Yield and Biomass Quality of Giant Reed (Arundo donax L.) as Affected by Harvest Time and Frequency

Giant reed (Arundo donax L.) is a perennial rhizomatous grass producing high biomass yields in temperate and warm climates under rainfed and reduced input conditions. Harvest time and frequency typically affect the productivity and suitability for energy conversion of energy crops. In order to evaluate the effect of different cutting managements on biomass yield and quality of giant reed, three single harvest (SH) and six double harvest (DH) systems were compared. Biomass yield, leaf mass ratio, dry matter (DM), and ash content were assessed for each harvest. Over the 2 years of study, giant reed demonstrated good productivity levels both when harvested once a year and twice a year (about 30 Mg ha−1) without significant differences between the treatments. Regarding double-cut regimes, overall yields were significantly reduced by delaying the second cut from autumn to winter (32.9 vs 30.2 Mg ha−1), and the percentage of the first cut with respect to the overall yield varied from 55 to 80 %. Biomass quality was also significantly affected by harvest time and frequency. The biomass obtained in double harvest systems showed higher average moisture levels (about 40 % DM) and ash concentrations ranging from 4.7 to 8.7 %. In contrast, single harvest systems led to a drier biomass (47–57 % DM) and reduced mineral contents (3.4–4.8 % ash). The feasibility of double-cut management should therefore be considered in terms of the specific giant reed-based supply chain, with particular regards to the storage and conversion technology adopted

Suitability of switchgrass (Panicum virgatum L.) as a forage crop in the Mediterranean area

In Mediterranean rainfed cropping systems, drought-resistant crops can increase yield and availability of forage during the summer period. In North America, switchgrass (Panicum virgatum L.) has been used for decades as pasture and fodder. In Europe, switchgrass has been investigated mainly for its potential as an energy crop. e overall aim of the present study was to analyse the suitability of switchgrass as a forage crop in a Mediterranean environment. A eld trial was carried out in Central Italy (Pisa) to evaluate the productivity and nutritive value in mature stands of two switchgrass varieties (Alamo and Blackwell). Alamo reached the maturity for hay harvest (boot stage) in August, about one-month delay with respect to Blackwell. At this stage, the biomass was 13.3 and 7.5 t ha-1 of dry matter (DM) in Alamo and Blackwell, respectively. Both varieties produced a summer regrowth harvested in autumn. Nutritive value declined during the growing season due to the increase of bre and the reduction of protein content. Saponin content signi cantly di ered between varieties and according to the growth stage, ranging from 1.8 to 4.5 mg g-1 DM. is study provides useful knowledge to favour the introduction of perennial grasses as forage crops in the Mediterranean, leading to several environmental bene ts when compared with the annual species that currently cover half of the forage cropland in Tuscany

Two years monitoring of soil N2O emissions on durum wheat in a Mediterranean area: the effect of tillage intensity and N-fertilizer rate

Two years monitoring of soil N2O emissions on durum wheat in a Mediterranean area: the effect of tillage intensity and N-fertilizer rate. EGU General Assembly 2016 Conference Abstracts, European Geophysical Unio

Decoding odor quality and intensity in the Drosophila brain

To internally reflect the sensory environment, animals create neural maps encoding the external stimulus space. From that primary neural code relevant information has to be extracted for accurate navigation. We analyzed how different odor features such as hedonic valence and intensity are functionally integrated in the lateral horn (LH) of the vinegar fly, Drosophila melanogaster. We characterized an olfactory-processing pathway, comprised of inhibitory projection neurons (iPNs) that target the LH exclusively, at morphological, functional and behavioral levels. We demonstrate that iPNs are subdivided into two morphological groups encoding positive hedonic valence or intensity information and conveying these features into separate domains in the LH. Silencing iPNs severely diminished flies' attraction behavior. Moreover, functional imaging disclosed a LH region tuned to repulsive odors comprised exclusively of third-order neurons. We provide evidence for a feature-based map in the LH, and elucidate its role as the center for integrating behaviorally relevant olfactory information