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Approcci eco-sostenibili per il controllo della contaminazione di ocratossina in alimenti destinati al consumo umano e animale
Full text linkMycotoxins are secondary metabolites produced by some filamentous fungi under certain conditions. The most important fungal genera producing mycotoxins that are found in food products are Aspergillus, Fusarium, Alternaria, and Penicillium. Ochratoxin A (OTA) has hepatotoxic, teratogenic, nephrotoxic and carcinogenic effect in mammals and it is classified as a group 2B carcinogen by the World Health Organization. The European Union has set the maximum OTA level at 2 μg/kg in wine, grape juice, and at 3 μg/kg for all products derived from cereal, including cereal products and cereal grains for human consumption. Some species of Aspergillus are the main source of OTA in warm and tropical regions, and in particular, Aspergillus carbonarius (Bainier) Thom is considered one of the most relevant OTA producers in food and feed. Hence, there is a need to develop alternative methods for pathogenic fungi and food contaminant control that will either individually or synergistically eradicate the OTA-producing fungi, by preventing mycotoxin biosynthesis, inactivating mycotoxins, or breaking them down into less or non-toxic compounds. Inhibiting the growth of OTA-producing fungi on sensitive commodities is by far the most reliable method to prevent OTA contamination of food and feed. Moreover, yeasts antagonists were evaluated able to reduce the spread of ochratoxin-producing fungi, as well as to represent the basis for biological tools to remove traces of mycotoxin from food and feed
The Role of mechanical stress in progression of intima hyperplasia associated to vein coronary bypass grafts disease
Full text linkCoronary artery bypass grafting is a surgical procedure introduced to restore the blood circulation into the myocardium after an ischemic event. Despite progress in the use of arterial conduits, saphenous vein (SV) remains one of the most used vessels for the bypass. A short time after bypass implantation SV undergoes intima hyperplasia (IH) that progressively reduce its patency. One trigger cause of IH is the hemodynamic changes in the blood flow with higher sheer stress on the endothelial layer a radial deformation on the wall of the vein.
The aim of this project was to understand the role of saphenous vein progenitors (SVP) in the progression of IH. These cells with high differentiation potential are the pericytes of vasa vasorum in the tunica adventitia.
By in vitro and ex vivo models of mechanical stress we demonstrated the susceptibility of SVPs to the strain that causes a cytoskeletal reorganization and the acquisition of a potential migratory phenotype. SVPs showed the stimulus-related up-regulation of Amphoterin-Induced Gene And Open Reading Frame 2 (AMIGO2), that may have a role in the mechanical activation via prosurvival and migratory effects.
For the first time has been described the presence of AMIGO2 in SVPs and its relationship with mechanical stress. Migratory phenotype acquisition and AMIGO2 overexpression demonstrate how SVPs are potential targets for further study of IH
Peripheral neuromodulation for drug-resistant epilepsy: the effect of short term transcutaneous trigeminal nerve stimulation on EEG activity
Full text linkAim: Trigeminal nerve stimulation (TNS) has been proven to exert beneficial effects on symptoms of drug-resistant epilepsy (DRE). However, whether and how TNS is able to modulate the electroencephalogram (EEG) background activity in DRE patients is still unknown. We aimed to investigate the effect of acute TNS on EEG activity by conducting qualitative (morphologic) and quantitative (power spectra) analyses on two groups of DRE patients, undergoing real or sham TNS.
Methods: Twenty-two DRE patients were randomly divided into a “sham-TNS” or “real-TNS” group. Real-TNS was delivered bilaterally to the infraorbital nerve with trains of a symmetric biphasic square wave pulse (1 to 20 mA, 120 Hz), in a cyclic modality for 20 minutes. The sham-TNS protocol mimicked the real-TNS stimulation but at a zero intensity. EEG recordings were collected for each patient 10 minutes pre, 20 minutes during and 10 minutes post TNS delivery. EEG signal was subsequently visually analysed for interictal epileptiform discharge (IEDs) and processed by spectral analysis (Fast Fourier Transform). A between and within subject repeated-measures ANOVA was used for statistical analyses.
Results: A significant increase of EEG absolute alpha power was observed in the during real-TNS compared to the sham-TNS (F2,18=1.748; p=0.006). Conversely, no significant effects were noticed either for quantitative analysis of other frequency bands or for IEDs detection.
Conclusion: Short-term TNS is able to induce an acute effect on EEG background composition of DRE patients. In line with recent evidence, alpha rhythm enhancement might be interpreted as an index of functional inhibition, able to influence cortical activity and thus reduce seizure propensity
Immunogenecity of <i>Mycobacterium avium</i> subsp. <i>paratuberculosis</i> epitopes cross-reacting with human ZnT8 and proinsulin peptides in autoimmune diabetes
Full text linkAlthough numerous studies put in evidence the increasing incidence of type 1 diabetes (T1D), its cause remains unclear. The role of Mycobacterium avium subsp. paratuberculosis (MAP) as a putative environmental agent triggering or accelerating the disease has been previously hypothesized in Sardinian and Italian T1D populations. The present thesis further sustains this association by reporting an elevated seroreactivity to MAP-derived epitopes and homologous human peptides corresponding to proinsulin and ZnT8 fragments in populations at different T1D stages and originating from distinct biogeographic backgrounds. Anti-MAP antibodies (Abs) resulted detectable in the first months of life before the appearance of classical autoantigens and, in most cases, were maintained in time making the selected peptides good candidates for early biomarkers. Likewise, Abs responses to the same antigens were observed among LADA patients and subjects affected by Hashimoto’s thyroiditis which frequently complicates T1D. Validation with a MAP-specific lipopentapeptide confirmed these results in coincidence with a stable Abs status. In PBMC primary culture, ZnT8 peptide and its MAP homolog induced the expression of proinflammatory cytokines along with increased cell-mediated responses and apoptosis. Good correlation between values obtained for the homologous MAP/human peptide pairs point at cross-reactivity through which mechanisms of self tolerance may be disrupted leading to autoimmunity
Antiproliferative activity of Verteporfin in Embryonal and Alveolar Rhabdomyosarcoma cell lines
Full text linkRhabdomyosarcoma (RMS) is a pediatric tumor, which arises from muscle precursor cells. Recently, it has been demonstrated that Hippo Pathway (Hpo) is involved in tumorigenesis of RMS. Thanks to its kinase cascade, which activates Yes-Associated Protein 1 (YAP1-YAP) and transcriptional co-activator with PDZ-binding motif (TAZ), Hpo is able to activate several physiological and biological features. YAP and TAZ are the heart of Hpo and they showed to have both cytoplasmic and nuclear role. In the nucleus, YAP is able to bind TEAD factors and constitute a complex that activates the transcription of several genes such as MYC, Tbx5 and PAX8 or maintains the stability of others like p73.
The key role of YAP and TAZ in cancer is leading to the development of new compounds able to block their action. One of these drugs is called Verteporfin (VP). This molecule is able to stop the formation of YAP/TEAD complex in the nucleus.
Considering that RMS is an aggressive tumor and that YAP recovers an important role on it, the aim of this project was to understand if VP is able to have a specific effect on RMS cell lines.
This work showed that VP has an antiproliferative action on RMS cell lines. VP perturbs cell cycle in a different manner depending on RMS cell lines. Through its action, VP modifies also the phenotype of RMS cells. Moreover, this drug is able to induce the activation of apoptosis mechanism through the cleavage of PARP protein in RMS cell lines. Furthermore, siRNA-induced knock down of YAP clarifies that VP induces anti proliferative action through other mechanism
Production of space: reproduction of mining landscape in Sardinia
Full text linkThe research examined mining landscape in Sardinia (Geo-mining, Historical and Environmental Park in Sardinia) as a place for everyday living. Developed within the theoretical framework of ‘production of space’ and cultural landscape concept it challenged place to identify and public participation in heritage conservation. Topic-specific theoretical principles and cases of practice have shown central role of everyday life routine and public participation in making-decision process for long-term heritage sustainability. Comprehensive elaboration of mining landscape in Sardinia confirmed domination of abstract space (bureaucracy and economy - mining industry in the past) that has modelled the landscape ever since. Productive synthesis of theoretical findings and international practices complemented the guidelines for the Sardinian case. Reproduction model illustrated components to the interpretative, evaluative and transformative value of mining landscape in Sardinia. Place identity (bound of place and people) is vital for reproduction of mining landscape in Sardinia as a place for living and loving. Both theory and practice, suggest territoriality of place-specific identities. The development principles focused rethinking the heritage conception on the regional level but starting from and with the local community. Research suggests more amplification of everyday life practices for a particular site of the mining landscape in Sardinia
Phenology and characterization of virgin olive oils from admitted to PDO “Sardegna”, minor Sardinian and international varieties
Full text linkGlobal virgin olive oil (VOO) production and consumption constantly increased during last 20 years. The expansion of growing areas in southern Mediterranean and in new countries, together with the enhancement of growing techniques, has led a reduction of production costs, maximizing productivity. Interest on the high quality and the nutraceutic properties of VOO is rising.
The wide biodiversity of Italian olive germplasm is an important resource for improve quality, differentiate and promote specific productions.
The aim of this thesis is to improve the knowledge of the Sardinian olive germplasm, with a particular focus on those varieties that characterize PDO “Sardegna”, trying to identify the ones that might contribute better to improve label’s quality.
In a three years field test, phenological behavior and interaction with meteorological conditions of 26 local and national varieties were evaluated. Corresponding olives samples were processed and monovarietal VOO were analyzed. The influence of harvest period on the VOO quality of 3 Sardinian varieties was studied. Similar environmental, agronomic and extraction conditions were maintained.
The study of phenological behavior and VOO composition revealed some peculiar qualitative aspects, specific of some varieties. Moreover, genetic factor affected fruit ripening process. Further studies might help to evaluate better the potentialities and valorization of minor varieties
Aspetti del paesaggio zootecnico della Sardegna
Full text linkThe landscape of Sardinia is eminently zootechnical. It is a paradigm of the archaic mediterranean pastoral landscape, because the processes that have generated and maintained it through the centuries have been preserved. First of all, sheep farming, around which culture still spins the life of the island. The zootechnical landscape is defined by an analysis of the most interesting concepts proposed by various authors, and is dealt in analytical terms, trying to map a variable that expresses the probability of incurring a zootechnical landscape, and from a historical and cultural point of view, re-proposing the work of the geographer Le Lannou, for a subdivision of the land into macro-landscapes. Finally, it is evident that the zootechnical landscape evolves, along with changes in the zootechnical sector, towards new configurations that call into question the forest, and therefore forest landscapes
Energie rinnovabili: paesaggio, territorio e collettività locali
Full text linkSecuring a sustainable and reliable energy supply is one of the main topics of the environmental issues we are facing today. Energy transition to more sustainable energy systems is supposed to resolve not only the decreasing availability of fossil fuels, but also the environmental and social issues the actual energy systems entail. Renewable energy systems deal not only with economical and technical issues, but also spatial issues, which comes as implications of the low energy efficiency obtainable from the main renewable sources, that require large areas of installation. The blueprinting and implementation of sustainable patterns of life cannot overlook the territoriality they entail, and the echoes on local systems, which are tangible and quantifiable on the one hand, and intangible and elusive on the other hand. The research is aimed to understand the landscape evolution caused by the forthcoming renewable energy systems. Furthermore, consequent topic is understand how a productive energy landscape can be translated in a sustainable landscape, including the environmental and social issues here implied. Therefore, sustainable energy systems rely on a substantial local involvement, resulting in community-owned and managed energy systems, as a result of both, grassroot actions and mainstream energy policy
Quinoxaline derivatives as new inhibitors of coxsackievirus B5
No full textEnteroviruses are among the most common and important human pathogens for which there are no specific antiviral agents approved by the US Food and Drug Administration so far. Particularly, coxsackievirus infections have a worldwide distribution and can cause many important diseases. We here report the synthesis of new 14 quinoxaline derivatives and the evaluation of their cytotoxicity and antiviral activity against representatives of ssRNA, dsRNA and dsDNA viruses. Promisingly, three compounds showed a very potent and selective antiviral activity against coxsackievirus B5, with EC50 in the sub-micromolar range (0.3–0.06 μM). A combination of experimental techniques (i.e. virucidal activity, time of drug addition and adsorption assays) and in silico modeling studies were further performed, aiming to understand the mode of action of the most active, selective and not cytotoxic compound, the ethyl 4-[(2,3-dimethoxyquinoxalin-6-yl)methylthio]benzoate (6)