Interacting Discovery Processes on Complex Networks

Innovation is the driving force of human progress. Recent urn models reproduce well the dynamics through which the discovery of a novelty may trigger further ones, in an expanding space of opportunities, but neglect the effects of social interactions. Here we focus on the mechanisms of collective exploration and we propose a model in which many urns, representing different explorers, are coupled through the links of a social network and exploit opportunities coming from their contacts. We study different network structures showing, both analytically and numerically, that the pace of discovery of an explorer depends on its centrality in the social network. Our model sheds light on the role that social structures play in discovery processes

Effect of shelf conditions on the phenolic fraction and oxidation indices of monovarietal extra virgin olive oil from cv. ‘Taggiasca’

The quality of monovarietal extra virgin olive oil from cv. ‘Taggiasca’ is influenced by many factors that have impact on shelf-life as well as on sensory and healthy properties of the product. The aim of the work was to recreate the conditions similar to those in consumer sales point (conditions of “shelf”), maintaining the olive oil packaged in dark-green bottles at room temperature (between 18 and 25 °C) under artificial light and away from heat sources, monitoring the oils up to 12 months from bottling with quarterly sampling for the main chemical, physico-chemical, and sensory parameters related to the quality. After one year of storage, an organoleptic alteration with reduction of the attributes ‘fruity’, ‘pungent’, and ‘bitter’, as well as the occurrence of ‘rancid’ defect, was observed. This alteration was found to be accompanied by a decrease in phenolic substances and tocopherols and an increase in primary and secondary oxidation products. The composition of the volatile fraction showed a slight increase of substances related to rancid defect, a constant trend of compounds related to fruitiness, and a slight decrease in alcohols. It can be concluded that the optimum time of storage of the oil under the above-mentioned conditions is approximately 9 months

Beneficial effects of curtailing immune susceptibility in an Alzheimer's disease model

Background Currently, there are no effective therapeutic options for Alzheimer's disease, the most common, multifactorial form of dementia, characterized by anomalous amyloid accumulation in the brain. Growing evidence points to neuroinflammation as a major promoter of AD. We have previously shown that the proinflammatory cytokine TNFSF10 fuels AD neuroinflammation, and that its immunoneutralization results in improved cognition in the 3xTg-AD mouse. Methods Here, we hypothesize that inflammatory hallmarks of AD might parallel with central and peripheral immune response dysfunction. To verify such hypothesis, we used a triple transgenic mouse model of AD. 3xTg-AD mice were treated for 12 months with an anti-TNFSF10 antibody, and thereafter immune/inflammatory markers including COX2, iNOS, IL-1 beta and TNF-alpha, CD3, GITR, and FoxP3 (markers of regulatory T cells) were measured in the spleen as well as in the hippocampus. Results Spleens displayed accumulation of amyloid-beta(1-42) (A beta(1-42)), as well as high expression of Treg cell markers FoxP3 and GITR, in parallel with the increased levels of inflammatory markers COX2, iNOS, IL-1 beta and TNF-alpha, and blunted IL-10 expression. Moreover, CD3 expression was increased in the hippocampus, consistently with FoxP3 and GITR. After chronic treatment of 3xTg-AD mice with an anti-TNFSF10 antibody, splenic FoxP3, GITR, and the above-mentioned inflammatory markers expression was restored to basal levels, while expression of IL-10 was increased. A similar picture was observed in the hippocampus. Such improvement of peripheral and CNS inflammatory/immune response was associated with decreased microglial activity in terms of TNF alpha production, as well as decreased expression of both amyloid and phosphorylated tau protein in the hippocampus of treated 3xTg-AD mice. Interestingly, we also reported an increased expression of both CD3 and FoxP3, in sections from human AD brain. Conclusions We suggest that neuroinflammation in the brain of 3xTg-AD mice triggered by TNFSF10 might result in a more general overshooting of the immune response. Treatment with an anti-TNFSF10 antibody blunted inflammatory processes both in the spleen and hippocampus. These data confirm the detrimental role of TNFSF10 in neurodegeneration, and corroborate the hypothesis of the anti-TNFSF10 strategy as a potential treatment to improve outcomes in AD

Influencia de un cosechado nocturno de aceitunas en “Salento” sobre la calidad del aceite de oliva virgen extra

In southern Italy, some olive cultivars such as ‘Ogliarola Salentina’ ripen when the day temperature is still high, at up to 28 to 30 °C. This can affect both the oil quality and the expression of its valuable characteristics. In addition, it increases the risk of undesirable fermentation that can generate off-flavors. In the present study, nocturnal olive harvesting was carried out to determine the influence that temperature can have on the characteristics of the extra virgin olive oil, and particularly on the volatile and oxidative compounds. The data obtained are encouraging: the lower temperatures that occur during the night appear to have a particular and positive impact on the organoleptic characteristics of the extra virgin olive oil produced, with enhanced formation of the volatile compounds that contribute to the ‘green’ notes of the flavor. In areas where daytime temperatures are very high, the nocturnal harvesting of olives at the correct stage of maturity therefore represents a good agronomic practice for the production of oils with high organoleptic and nutritional merit.En el sur de Italia, algunas variedades de olivo maduran cuando la temperatura del día sigue siendo alta, hasta 28 °C a 30 °C. Esto puede perjudicar la calidad del aceite y a la expresión de sus valiosas características, y aumenta el riesgo de fermentación indeseable que puede generar malos sabores. En el presente estudio, la cosecha nocturna de aceitunas se llevó a cabo para determinar la influencia que la temperatura puede tener sobre las características del aceite de oliva virgen extra, y en particular sobre los compuestos volátiles y los compuestos relacionados con la oxidación. Los datos obtenidos son alentadores: las temperaturas más bajas que se producen durante la noche parecen tener un impacto positivo en las características organolépticas del aceite de oliva virgen extra producido, con una mejora de la formación de los compuestos volátiles que contribuyen a las notas “verdes” del sabor. En las zonas donde las temperaturas diurnas son muy altas, la cosecha nocturna de aceitunas, representa, por tanto, una buena práctica agronómica para la producción de aceites con grandes ventajas organoléptica y nutritivas

Agronomic, nutritional and nutraceutical aspects of durum wheat (Triticum durum Desf.) cultivars under low input agricultural management

Among cereals, durum wheat has a central role in the Italian diet and economy, where there is a historical tradition of pasta making. In the present study, we evaluated the nutrient and nutraceutical properties of 2 old and 6 modern durum wheat varieties grown under low input agricultural management. Considering the lack of available data on the adaptability of existing durum wheat varieties to the low input and organic sectors, the research aimed at providing a complete description of the investigated genotypes, considering the agronomic performance as well as the nutrient and phytochemical composition. The experimental trials were carried out at the same location (Bologna, Northern Italy) for two consecutive growing seasons (2006/2007, 2007/2008). No clear distinction between old and modern varieties was observed in terms of grain yield (mean values ranging from 2.5 to 4.0 t/ha), highlighting that the divergence in productivity, normally found between dwarf and non-dwarf genotypes, is strongly reduced when they are cropped under low input management. All durum wheat varieties presented high protein levels and, in addition, provided remarkable amounts of phytochemicals such as dietary fibre, polyphenols, flavonoids and carotenoids. Some of the investigated genotypes, such as Senatore Cappelli, Solex, Svevo and Orobel, emerged with intriguing nutritional and phytochemical profiles, with the highest levels of dietary fibre and antioxidant compounds. The study provided the basis for further investigations into the adaptability of the durum wheat genotypes to low input management, for the selection of genotypes characterised by higher yield and valuable nutrient and nutraceutical quality

Analysis of viral nucleic acids in duodenal biopsies from adult patients with active celiac disease: in search for an etiological relationship

BACKGROUND AND AIM: Celiac Disease (CD) is a multisystemic chronic inflammatory autoimmune disease which develops in genetically predisposed subjects and it is triggered by the ingestion of gluten. After the interaction between HLA-DQ2/DQ8 and gluten-derived peptides, lymphocytes T CD4+ start a specific immune response which ends in a chronic inflammation and mucosal damage. CD pathogenesis is complex and not entirely understood, probably due to an alteration in the gastrointestinal immune system or to its aberrant regulation. Furthermore, many environmental and immune factors could be involved, particularly viral infections. The aim of the study was to observe possible relationships between CD and infections from HHV-6 A/B, EBV, CMV, adenovirus and rotavirus. MATERIAL AND METHODS: Thirty-nine adult patients (aged 18-65 yrs) have been enrolled: specifically, 24 duodenal biopsies from active CD patients and 15 biopsies from non-CD patients were analyzed. CD diagnosis has been performed by means of serological antibodies, histology of duodenal biopsies and duodenal biopsy organ culture. Viral nucleic acids were extracted from duodenal biopsies and then amplified using Real-Time PCR technique. RESULTS: HHV-6B was found in 62.5% of CD patients and in 73.3% of non-CD patients (p=0.13). EBV was found in 4.5% of CD patients and 6.7% of non-CD patients (p=0.35). Nucleic acids from HHV-6A, CMV, adenovirus and rotavirus were not detected in any group. HHV-6B viral load in CD patients was higher than in non-CD patients, but data were not statistically significant (p=0.54). CD patients with HHV-6B viral load >50000 copies/ml resulted to be younger and had lower anti-tTG antibody titers found at organ culture than patients with lower HHV-6B viral load (p>0.05). CONCLUSIONS: There seems to be no difference in viral load and/or in the detection of viruses between CD and non-CD patients. Thus, our data do not support the possible relationship between CD and viral infections, although a larger population is needed to confirm our study results

Recurrence of gastrointestinal and extra-intestinal symptoms in celiac patients affected by nickel allergic contact mucositis: when proper gluten-free diet is not enough

BACKGROUND AND AIM: Nickel (Ni) is a metal widely present in nature and the prevalence of Ni allergy is increasing. Allergic contact mucositis (MAC) induced by Ni-rich foods is often responsible for IBS-like disorders and it can be diagnosed by means of a Ni oral mucosa patch test (omPT). It has been observed that, after several months of correct gluten-free diet (GFD), many celiac disease (CD) patients show a recrudescence of gastrointestinal and extra-intestinal symptoms, although serological and histological remission has been achieved. This can be due to a Ni load induced by GFD: a greater consumption of Ni-rich foods (e.g. corn) would lead to a consequent intestinal sensitization to Ni in predisposed subjects. Our study aimed to assess the role played by Ni in the recurrence of symptoms in CD subjects after strict GFD. MATERIAL AND METHODS: Twenty celiac patients (all female, age 23-65 yrs) in serological and histological remission after at least 12 months of GFD have been consecutively included: they all were complaining recurrence gastrointestinal and extra-intestinal symptoms. Subjects with organic gastrointestinal pathologies were excluded. A symptom questionnaire (GSRS modified according to the Salerno Experts' Criteria) has been administered to all patients in 4 stages: T0 (during free diet - active CD); T1 (after 12 months of GFD - CD remission); T2 (during GFD - recurrence of symptoms); T3 (during GFD and after 3 months of low-Ni diet). Ni omPT was performed at T2. Statistical analysis was performed using Wilcoxon signed rank test. RESULTS: All 20 patients showed positive Ni omPT, with local and/or systemic alterations confirming Ni ACM diagnosis. The analysis obtained by comparing T2-T3 showed p-value <0.01 for: abdominal pain, bloating, swelling, increased number of evacuations, dermatitis, asthenia; p-value values <0.05 for: heartburn, acid regurgitation, borborygmus, flatulence, loose stools, urgent need for defecation, headache. The other variables were statistically not significant. CONCLUSIONS: Our data suggest that gastrointestinal and extra-intestinal symptoms observed in CD subjects after prolonged and correct GFD may be due to the necessary dietary change and an increased Ni intake. Specifically, these patients developed Ni MAC, diagnosed by specific Ni omPT. We also observed that regression of symptoms may occur after a proper low-Ni diet. We can conclude that GFD may lead to an increased consumption of Ni-rich foods and this could explain the recurrence of apparently gluten-dependent symptoms

Human Adipose-Derived Stem Cells in Madelung's Disease: Morphological and Functional Characterization

Madelung Disease (MD) is a syndrome characterized by the accumulation of aberrant symmetric adipose tissue deposits. The etiology of this disease is yet to be elucidated, even though the presence of comorbidities, either genetic or environmental, has been reported. For this reason, establishing an in vitro model for MD is considered crucial to get insights into its physiopathology. We previously established a protocol for isolation and culture of stem cells from diseased tissues. Therefore, we isolated human adipose-derived stem cells (ASC) from MD patients and compared these cells with those isolated from healthy subjects in terms of surface phenotype, growth kinetic, adipogenic differentiation potential, and molecular alterations. Moreover, we evaluated the ability of the MD-ASC secretome to affect healthy ASC. The results reported a difference in the growth kinetic and surface markers of MD-ASC compared to healthy ASC but not in adipogenic differentiation. The most commonly described mitochondrial mutations were not observed. Still, MD-ASC secretome was able to shift the healthy ASC phenotype to an MD phenotype. This work provides evidence of the possibility of exploiting a patient-based in vitro model for better understanding MD pathophysiology, possibly favoring the development of novel target therapies