417 research outputs found
Spatial Frequency Tuning of Body Inversion Effects
Body inversion effects (BIEs) reflect the deployment of the configural processing of body stimuli. BIE modulates the activity of body-selective areas within both the dorsal and the ventral streams, which are tuned to low (LSF) or high spatial frequencies (HSF), respectively. The specific contribution of different bands to the configural processing of bodies along gender and posture dimensions, however, is still unclear. Seventy-two participants performed a delayed matching-to-sample paradigm in which upright and inverted bodies, differing for gender or posture, could be presented in their original intact form or in the LSF- or HSF-filtered version. In the gender discrimination task, participantsâ performance was enhanced by the presentation of HSF images. Conversely, for the posture discrimination task, a better performance was shown for either HSF or LSF images. Importantly, comparing the amount of BIE across spatial-frequency conditions, we found greater BIEs for HSF than LSF images in both tasks, indicating that configural body processing may be better supported by HSF information, which will bias processing in the ventral stream areas. Finally, the exploitation of HSF information for the configural processing of body postures was lower in individuals with higher autistic traits, likely reflecting a stronger reliance on the local processing of body-part details
Natural Sulfur-Containing Compounds: An Alternative Therapeutic Strategy against Liver Fibrosis
Liver fibrosis is a pathophysiologic process involving the accumulation of extracellular matrix proteins as collagen deposition. Advanced liver fibrosis can evolve in cirrhosis, portal hypertension and often requires liver transplantation. At the cellular level, hepatic fibrosis involves the activation of hepatic stellate cells and their transdifferentiation into myofibroblasts. Numerous pro-fibrogenic mediators including the transforming growth factor-ÎČ1, the platelet-derived growth factor, endothelin-1, toll-like receptor 4, and reactive oxygen species are key players in this process. Knowledge of the cellular and molecular mechanisms underlying hepatic fibrosis development need to be extended to find novel therapeutic strategies. Antifibrotic therapies aim to inhibit the accumulation of fibrogenic cells and/or prevent the deposition of extracellular matrix proteins. Natural products from terrestrial and marine sources, including sulfur-containing compounds, exhibit promising activities for the treatment of fibrotic pathology. Although many therapeutic interventions are effective in experimental models of liver fibrosis, their efficacy and safety in humans are largely unknown. This review aims to provide a reference collection on experimentally tested natural anti-fibrotic compounds, with particular attention on sulfur-containing molecules. Their chemical structure, sources, mode of action, molecular targets, and pharmacological activity in the treatment of liver disease will be discussed
Antifibrotic effect of marine ovothiol in an in vivo model of liver fibrosis
Liver fibrosis is a complex process caused by chronic hepatic injury, which leads to an excessive increase in extracellular matrix protein accumulation and fibrogenesis. Several natural products, including sulfur-containing compounds, have been investigated for their antifibrotic effects; however, the molecular mechanisms underpinning their action are partially still obscure. In this study, we have investigated for the first time the effect of ovothiol A, Ï-methyl-5-thiohistidine, isolated from sea urchin eggs on an in vivo murine model of liver fibrosis. Mice were intraperitoneally injected with carbon tetrachloride (CCl 4 ) to induce liver fibrosis and treated with ovothiol A at the dose of 50 mg/kg 3 times a week for 2 months. Treatment with ovothiol A caused a significant reduction of collagen fibers as observed by histopathological changes and serum parameters compared to mice treated with control solution. This antifibrotic effect was associated to the decrease of fibrogenic markers involved in liver fibrosis progression, such as the transforming growth factor (TGF-ÎČ), the α-smooth muscle actin (α-SMA), and the tissue metalloproteinases inhibitor (TIMP-1). Finally, we provided evidence that the attenuation of liver fibrosis by ovothiol A treatment can be regulated by the expression and activity of the membrane-bound Îł-glutamyl-transpeptidase (GGT), which is a key player in maintaining intracellular redox homoeostasis. Overall, these findings indicate that ovothiol A has significant antifibrotic properties and can be considered as a new marine drug or dietary supplement in potential therapeutic strategies for the treatment of liver fibrosis
Modulation of Gut Microbiota and Neuroprotective Effect of a YeastâEnriched Beer
Beer is the most consumed alcoholic beverage worldwide. It is rich in nutrients, and with its microbial component it could play a role in gut microbiota modulation. Conflicting data are currently available regarding the consequences of alcohol and alcoholâcontaining beverages on dementia and ageâassociated disorders including Alzheimerâs disease (AD), a neurodegeneration characterized by protein aggregation, inflammatory processes and alterations of components of the
gutâbrain axis. The effects of an unfiltered and unpasteurized craft beer on AD molecular hallmarks, levels of gut hormones and composition of micro/mycobiota were dissected using 3xTgâAD mice.
In addition, to better assess the role of yeasts, beer was enriched with the same Saccharomyces cerevisiae strain used for brewing. The treatment with the yeastâenriched beer ameliorated cognition and favored the reduction of A(1â42) and proâinflammatory molecules, also contributing to an
increase in the concentration of antiâinflammatory cytokines. A significant improvement in the richness and presence of beneficial taxa in the gut bacterial population of the 3xTgâAD animals was observed. In addition, the fungal order, Sordariomycetes, associated with gut inflammatory
conditions, noticeably decreased with beer treatments. These data demonstrate, for the first time, the beneficial effects of a yeastâenriched beer on AD signs, suggesting gut microbiota modulation as a mechanism of action
Modelling Clock Synchronization in the Chess gMAC WSN Protocol
We present a detailled timed automata model of the clock synchronization
algorithm that is currently being used in a wireless sensor network (WSN) that
has been developed by the Dutch company Chess. Using the Uppaal model checker,
we establish that in certain cases a static, fully synchronized network may
eventually become unsynchronized if the current algorithm is used, even in a
setting with infinitesimal clock drifts
Health profile of the PASSI surveillance system according to the second self-audit data
Background. The surveillance system PASSI (Progresses in ASSessing adult population health in Italy) is centrally coordinated by the Istituto Superiore di Sanita (ISS) and carried on by Local Health Units (LHU) from all the 21 Italian Regional Health Authorities since 2008. PASSI monitors the main behavioural health-related risk factors among the adult population in order to better orient and further elaborate interventions for the prevention of major chronic diseases.Study design. Basing on outcomes from the first pilot study in 2011, we conducted a second self-audit to investigate and map levels of conformity with recognized implementation standards by the protocol for PASSI local management in the 21 Italian Regional Health Authorities.Methods. We designed an online questionnaire supported by an open source application (Google) and sent to the local PASSI coordinators. Data were collected from April to September 2013. 113 out of 148 LHUs from all the 21 Italian Regional Health Authorities participated, with a response rate of 76%.Results. Overall, in the respondent LHUs 1,036 professionals result to differently engage in surveillance activities. Although PASSI is locally-based, where data collection and computerisation are arranged, central support is highly appreciated in terms of quality monitoring, analysis, output processing, professional training, delivery of dissemination material. PASSI data are more used for communication (60%) and planning (80%) than to scientific ends.Conclusions. After a ten-year activity, PASSI as complex public health program requires periodical self-audit rounds in order to assess to what extent relevant performance indicators match the levels indicated in its own operational protocol. The second self-audit showed to be reliable concerning both sustainability and data collection. It then represents an experience that can be renewed and repeated
Computing Distances between Probabilistic Automata
We present relaxed notions of simulation and bisimulation on Probabilistic
Automata (PA), that allow some error epsilon. When epsilon is zero we retrieve
the usual notions of bisimulation and simulation on PAs. We give logical
characterisations of these notions by choosing suitable logics which differ
from the elementary ones, L with negation and L without negation, by the modal
operator. Using flow networks, we show how to compute the relations in PTIME.
This allows the definition of an efficiently computable non-discounted distance
between the states of a PA. A natural modification of this distance is
introduced, to obtain a discounted distance, which weakens the influence of
long term transitions. We compare our notions of distance to others previously
defined and illustrate our approach on various examples. We also show that our
distance is not expansive with respect to process algebra operators. Although L
without negation is a suitable logic to characterise epsilon-(bi)simulation on
deterministic PAs, it is not for general PAs; interestingly, we prove that it
does characterise weaker notions, called a priori epsilon-(bi)simulation, which
we prove to be NP-difficult to decide.Comment: In Proceedings QAPL 2011, arXiv:1107.074
The Biological Role of Vitamins in Athletesâ Muscle, Heart and Microbiota
Physical activity, combined with adequate nutrition, is considered a protective factor against cardiovascular disease, musculoskeletal disorders, and intestinal dysbiosis. Achieving optimal performance requires a significantly high energy expenditure, which must be correctly supplied to avoid the occurrence of diseases such as muscle injuries, oxidative stress, and heart pathologies, and a decrease in physical performance during competition. Moreover, in sports activities, the replenishment of water, vitamins, and minerals consumed during training is essential for safeguarding athletesâ health. In this scenario, vitamins play a pivotal role in numerous metabolic reactions and some muscle biochemical adaptation processes induced by sports activity. Vitamins are introduced to the diet because the human body is unable to produce these micronutrients. The aim of this review is to highlight the fundamental role of vitamin supplementation in physical activity. Above all, we focus on the roles of vitamins A, B6, D, E, and K in the prevention and treatment of cardiovascular disorders, muscle injuries, and regulation of the microbiome
- âŠ