Graphene oxide impairs the pollen performance of Nicotiana tabacum and Corylus avellana suggesting potential negative effects on the sexual reproduction of seed plants

The production of graphene based materials (GBMs) is steadily increasing but the effects of the possible release of GBMs in the environment are far from being understood. Graphene oxide (GO) is among the most active GBMs and it causes widely varying effects on the vegetative body of seed plants. However, nothing is known yet about its potential effects on the reproductive process. This study addresses the effects of GO on pollen germination and pollen tube elongation in the model species Nicotiana tabacum and in the non-model species Corylus avellana. In vitro germination experiments were conducted without or with GO (control and treated samples, respectively) at concentrations of 25, 50 and 100 μg mL−1. Pollen germination and tube elongation were affected at GO concentrations ≥50 μg mL−1, decreasing by 20% and 19% in N. tabacum and by 68% and 58% in C. avellana, respectively. GO did not affect the viability of N. tabacum pollen, but doubled the frequency of bent tubes. Microscopy observations of pollen tubes exposed to a cellpermeant, dual-excitation ratiometric pH indicator revealed that GO affected the intracellular pH homeostasis. Further germination experiments on C. avellana conducted by inverting the pH conditions of the control and treated (100 μg GO mL−1) samples demonstrated that the main factor influencing the pollen performance is the acidic properties of GO. This might affect the reproductive process of numerous seed plants thus being relevant from an environmental point of view

A DSS model for the governance of sustainable rural landscape: A first application to the cultural landscape of Orcia Valley (Tuscany, Italy)

There is a growing interest on landscape and landscape policy and planning, especially since the adoption of the European Landscape Convention in 2000. This latter defines landscape as "an area, as perceived by people, whose character is the result of the action and interaction of natural and/or human factors". In the case of rural landscape, this means that an appropriate governance model should not only involve local stakeholders in a participative approach, but also take into account natural characteristics, cultural aspects of the past and present, and socio-economic aspects, since agriculture is the main driver of change for rural landscapes. Farm strategies are influenced by internal and by external factors, these latter being related to market conditions and to constraints and opportunities given by policies. Market globalization and Agricultural policies are consequently having a strong impact on landscape, that public institutions try to neutralise setting rules about landscape conservation. Thus, due to its specific features, landscape is impacted both by several sectorial and territorial policies which have none or very low coordination among them. Indeed, Common Agricultural Policy (CAP) has often shown a negative influence on landscape, also in the case of Agri-Environmental Schemes (AES) intended to promote landscape. In this framework, the aim of this paper is to present a comprehensive model for the governance of rural landscape and a first simplified application to a cultural landscape. This model is based on the integration of a geographical multi-criteria analysis, an advanced GIS-based geo-processing tools, and participatory techniques aiming to understand and foresee local stakeholders' behaviours through focus-groups and dedicated interviews. The identification of future landscape scenarios is based on the integration of past evolution (historical analysis), landscape sensitivity (territorial analysis) and farmers' adaptation to market and policy changes (farm analysis). A simplified version of the model was tailored and tested in the municipality of Castiglione d'Orcia of the Siena province in Tuscany, Italy, one of the UNESCO cultural landscapes, but is the Authors' opinion that its approach

Selective fatty acid amide hydrolase inhibitors as potential novel antiepileptic agents

Temporal lobe epilepsy is the most common form of epilepsy, and current antiepileptic drugs are ineffective in many patients. The endocannabinoid system has been associated with an on-demand protective response to seizures. Blocking endocannabinoid catabolism would elicit antiepileptic effects, devoid of psychotropic effects. We herein report the discovery of selective anandamide catabolic enzyme fatty acid amide hydrolase (FAAH) inhibitors with promising antiepileptic efficacy, starting from a further investigation of our prototypical inhibitor 2a. When tested in two rodent models of epilepsy, 2a reduced the severity of the pilocarpine-induced status epilepticus and the elongation of the hippocampal maximal dentate activation. Notably, 2a did not affect hippocampal dentate gyrus long-term synaptic plasticity. These data prompted our further endeavor aiming at discovering new antiepileptic agents, developing a new set of FAAH inhibitors (3a–m). Biological studies highlighted 3h and 3m as the best performing analogues to be further investigated. In cell-based studies, using a neuroblastoma cell line, 3h and 3m could reduce the oxinflammation state by decreasing DNA-binding activity of NF-kB p65, devoid of cytotoxic effect. Unwanted cardiac effects were excluded for 3h (Langendorff perfused rat heart). Finally, the new analogue 3h reduced the severity of the pilocarpine-induced status epilepticus as observed for 2a

The differential modulation of the enzymes of glutathione metabolism - Indication of overlapping effects of toxicity and repair in mouse liver and kidney after dietary treatment with methyl mercury and sodium selenite

The effect of methylmercury (MM) and MM plus sodium selenite (SE) on the activity of various GSH-dependent enzymes was studied in the liver and kidney of mice. Ten groups of mice were fed diets containing graded proportions of MM, alone or with graded quantities of SE. GST, GSH-Px, and GSSG-RED were assayed in the cytosolic fraction of liver and kidney homogenates. After treatment with MM, instead of the expected decrease in enzyme activities, an increase was observed in the kidney and a small decrease in the liver with no dose-response relation in either organ. In protected groups, a general pattern of induction was observed in both organs, but again there was little evidence of dose-response relationships. Detailed analysis of the results suggests that the effects observed were not directly caused by MM or SE but are the resultant of complex interactions presumably related to contemporaneous mechanisms of damage and repair. © 1993 Humana Press Inc

A DSS Model for the Governance of Sustainable Rural Landscape

Резюме. В данной статье представлена модель, созданная на основе интеграции географического многофакторного анализа и современных инструментов гео-обработки, основанной на ГИС, направленных на выявление эволюционных путей фермерских хозяйств и сельскохозяйственного ландшафта. Модель интегрирует информацию о природных особенностях, культурных аспектах прошлого и настоящего, и социально-экономических аспектах развития хозяйств, поскольку сельское хозяйство является главным фактором изменений сельского ландшафта. На сельскохозяйственные стратегии влияют не только внутренние, но и внешние факторы, такие, как рыночные условия и политика, которые являются движущей силой изменений ландшафта, в то время как политика может также реагировать на проблемы сохранения и улучшения ландшафта. Определение сценариев развития будущего ландшафта основывается на интеграции прошлых изменений, чувствительности ландшафта и способности фермеров адаптироваться к изменениям рынка и политики. Первая версия модели была специально разработана и проверена в муниципалитете Кастильон д'Орча (Тоскана, Италия), принадлежащий к одному из самых известных культурных ландшафтов ЮНЕСКО в Италии.This paper presents a model based on the integration of a geographical multi-criteria analysis and advanced GIS-based geo-processing tools aiming at identifying farms' and rural landscape's evolutionary paths. The model integrates information about natural characteristics, cultural aspects of the past and present, and socio-economic aspects of farms, since agriculture is the main driver of change for rural landscape. Farm strategies are influenced by internal factors but also by external factors, such as market conditions and policies; which both are drivers of landscape changes, while policies could have also the role of response to problems of landscape maintenance and improvement. The identification of future landscape scenarios is based on the integration of past evolution, landscape sensitivity and farmers' adaptation capacity to market and policy changes. A first version of the model was tailored and tested in the Municipality of Castiglion d'Orcia (Tuscany, Italy), belonging to one of the most well known UNESCO cultural landscape of Italy

Effects of 2,5-di-t-butyl-1,4-benzohydroquinone (BHQ) on rat aorta smooth muscle

5To characterise the pharmacological activity of 2,5-di-t-butyl-1,4-benzohydroquinone (BHQ) on vascular smooth muscle, the different effects of BHQ on rat aorta were investigated under several experimental conditions. In aortic rings at rest or depolarised with 80 mM K+ in the presence of 1 microM nifedipine, BHQ evoked a slow tonic contraction which was antagonised by 1 mM Ni2+. Depolarised rings contracted in response to addition of 1 mM Ca2+, with an EC50 value of 32.4+/-1.0 mM for K+. At 20 mM K+, Ca2+-induced contraction was enhanced by BHQ. This effect was antagonised by 1 mM Ni2+, but not by 1 microM nifedipine. By contrast, at 40, 80 and 128 mM K+, BHQ antagonised Ca2+-induced contraction. This effect was partially reversed by 1 microM methyl-1,4-dihydro-2,6-dimethyl-3-nitro-4-(2-trifluoromethylphenyl)-pyri dine-5-carboxylate (Bay K 8644) or by increasing extracellular Ca2+ concentration. In the presence of nifedipine and Ni2+, depolarised rings (80 mM K+) contracted in response to addition of 1 microM phenylephrine; this response was fast and then slowly decreased. When the preparations were preincubated with BHQ, the phenylephrine-induced contraction was transient and antagonised in a concentration-dependent manner by BHQ. These results indicate that the myotonic effect of BHQ on rat aortic rings depends on activation of Ca2+ influx via a Ni2+-sensitive pathway, whereas its myolytic activity is due either to antagonism of Ca2+ entry via L-type Ca2+ channels or depletion of intracellular Ca2+ stores.reservedmixedFusi, Fabio; Gorelli, Beatrice; Valoti, Massimo; Marazova, K.; Sgaragli, GIAN PIETROFusi, Fabio; Gorelli, Beatrice; Valoti, Massimo; Marazova, K.; Sgaragli, GIAN PIETR