217 research outputs found
Differential neural dynamics underling pragmatic and semantic affordance processing in macaque ventral premotor cortex
Premotor neurons play a fundamental role in transforming physical properties of observed objects, such as size and shape, into motor plans for grasping them, hence contributing to "pragmatic" affordance processing. Premotor neurons can also contribute to "semantic" affordance processing, as they can discharge differently even to pragmatically identical objects depending on their behavioural relevance for the observer (i.e. edible or inedible objects). Here, we compared the response of monkey ventral premotor area F5 neurons tested during pragmatic (PT) or semantic (ST) visuomotor tasks. Object presentation responses in ST showed shorter latency and lower object selectivity than in PT. Furthermore, we found a difference between a transient representation of semantic affordances and a sustained representation of pragmatic affordances at both the single neuron and population level. Indeed, responses in ST returned to baseline within 0.5 s whereas in PT they showed the typical sustained visual-to-motor activity during Go trials. In contrast, during No-go trials, the time course of pragmatic and semantic information processing was similar. These findings suggest that premotor cortex generates different dynamics depending on pragmatic and semantic information provided by the context in which the to-be-grasped object is presented
The role of the monkey ventrolateral prefrontal cortex in the organization of intentional actions
A crucial aspect in the organization of intentional actions is the chaining of single motor acts into well organized motor sequences. In a pioneering experiment was demonstrated that inferior parietal neurons code grasping motor acts differently depending on the final goal of the action where the motor acts were embedded (grasp-to-eat or grasp-to-place). Similar findings have been reported by neurophysiological investigations carried out on the ventral premotor cortex. These results suggest the possible presence of a neural mechanism capable of integrating contextual information used by the monkey to decide which action to perform. Functional results and anatomical connections between the inferior parietal and ventral premotor areas suggest that cortico-cortical projections of different cortical areas can play a crucial role in the selection of inferior parietal and ventral premotor neuronal pools for the organization of intentional actions.
The ventrolateral prefrontal cortex appears one of the most plausible candidates to fulfill this function. In fact, several studies evidenced that the ventrolatelateral prefrontal cortex play a role in arranging motor chunks - such as pushing, pulling or turning ā into over-trained motor sequences based on learned sensory instructions.
The purpose of this study is to clarify, using a controlled behavioral paradigm, the possible contribution of ventrolateral prefrontal neurons to the integration of contextual information for the selection and generation of natural actions
Risultati clinico-patologici del carcinoma tiroideo con mutazione BRAFV600E nella popolazione giovane di Fukushima
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Selectivity for grip type and action goal in macaque inferior parietal and ventral premotor grasping neurons.
Grasping objects requires the selection of specific grip postures in relation to objects' physical properties. Furthermore, grasping acts can be embedded into actions aimed at different goals, depending on the context in which the action is performed. Here we assessed whether information on grip and action type integrate at the single neuron level within the parieto-frontal motor system. For this purpose, we trained three monkeys to perform simple grasp-to-eat and grasp-to-place actions, depending on contextual cues, in which different grip types were required, in relation to target features. We recorded 173 grasping neurons: 86 from the inferior parietal area PFG and 87 from the ventral premotor area F5. Results showed that most neurons in both areas are selective for the grip type, but the discharge of many of them, particularly in PFG, appears to differ in relation to action context. Kinematics data and control experiments indicated that neuronal selectivity appears to more likely depend on the action goal triggered by the context rather than on specific contextual elements. The temporal dynamics of grip and goal selectivity showed that grasping neurons reflect first "how" the object has to be grasped (grip), to guide and monitor the hand shaping phase, then "why" the action is performed (goal), very likely to facilitate subsequent motor acts following grasping. These findings suggest that, in the parieto-frontal system, grip types and action goals are processed by both parallel and converging pathways, and area PFG appears to be particularly relevant for integrating this information for action organization
A Logical Verification Methodology for Service-Oriented Computing
We introduce a logical verification methodology for checking behavioural properties of service-oriented computing systems. Service properties are described by means of SocL, a branching-time temporal logic that we have specifically designed to express in an effective way distinctive aspects of services, such as, e.g., acceptance of a request, provision of a response, and correlation among service requests and responses. Our approach allows service properties to be expressed in such a way that
they can be independent of service domains and specifications. We show an instantiation of our general methodology that uses the formal language COWS to conveniently specify services and the expressly developed software tool CMC to assist the user in the task of verifying SocL formulae over service specifications. We demonstrate feasibility and effectiveness of our methodology by means of the specification and the analysis of a case study in the automotive domain
Antioxidant and Anti-Inflammatory Effect of Cinnamon (Cinnamomum verum J. Presl) Bark Extract after In Vitro Digestion Simulation
Cinnamon bark is widely used for its organoleptic features in the food context and growing evidence supports its beneficial effect on human health. The market offers an increasingly wide range of food products and supplements enriched with cinnamon extracts which are eliciting beneficial and health-promoting properties. Specifically, the extract of Cinnamomum spp. is rich in antioxidant, anti-inflammatory and anticancer biomolecules. These include widely reported cinnamic acid and some phenolic compounds, such asproanthocyanidins A and B, and kaempferol. These molecules are sensitive to physical-chemical properties (such as pH and temperature) and biological agents that act during gastric digestion, which could impair molecules' bioactivity. Therefore, in this study, the cinnamon's antioxidant and anti-inflammatory bioactivity after simulated digestion was evaluated by analyzing the chemical profile of the pure extract and digested one, as well as the cellular effect in vitro models, such as Caco2 and intestinal barrier. The results showed that the digestive process reduces the total content of polyphenols, especially tannins, while preserving other bioactive compounds such as cinnamic acid. At the functional level, the digested extract maintains an antioxidant and anti-inflammatory effect at the cellular level
MTERF factors: a multifunction protein family.
AbstractThe MTERF family is a large protein family, identified in metazoans and plants, which consists of four subfamilies, MTERF1, 2, 3 and 4. Mitochondrial localisation was predicted for the vast majority of MTERF family members and demonstrated for the characterised MTERF proteins. The main structural feature of MTERF proteins is the presence of a modular architecture, based on repetitions of a 30-residue module, the mTERF motif, containing leucine zipper-like heptads. The MTERF family includes transcription termination factors: human mTERF, sea urchin mtDBP andDrosophilaDmTTF. In addition to terminating transcription, they are involved in transcription initiation and in the control of mtDNA replication. This multiplicity of functions seems to flank differences in the gene organisation of mitochondrial genomes. MTERF2 and MTERF3 play antithetical roles in controlling mitochondrial transcription: that is, mammalian andDrosophilaMTERF3 act as negative regulators, whereas mammalian MTERF2 functions as a positive regulator. Both proteins contact mtDNA in the promoter region, perhaps establishing interactions, either mutual or with other factors. Regulation of MTERF gene expression in human andDrosophiladepends on nuclear transcription factors NRF-2 and DREF, respectively, and proceeds through pathways which appear to discriminate between factors positively or negatively acting in mitochondrial transcription. In this emerging scenario, it appears that MTERF proteins act to coordinate mitochondrial transcription
Ongoing outbreak of hepatitis A in Italy: preliminary report as of 31 May 2013
Since January 2013, an unusual increase in hepatitis A cases has been detected in northern Italy. A total number of 352 cases were reported to the integrated surveillance system between January and the end of May 2013 and this represents a 70% increase compared to the same period of the previous year. The outbreak is ongoing and the public health authorities are continuing their investigations to establish the transmission vehicle and to control the outbreak
IL32 downregulation lowers triglycerides and type I collagen in di-lineage human primary liver organoids
Steatotic liver disease (SLD) prevails as the most common chronic liver disease yet lack approved treatments due to incomplete understanding of pathogenesis. Recently, elevated hepatic and circulating interleukin 32 (IL -32) levels were found in individuals with severe SLD. However, the mechanistic link between IL -32 and intracellular triglyceride metabolism remains to be elucidated. We demonstrate in vitro that incubation with IL -32b protein leads to an increase in intracellular triglyceride synthesis, while downregulation of IL32 by small interfering RNA leads to lower triglyceride synthesis and secretion in organoids from human primary hepatocytes. This reduction requires the upregulation of Phospholipase A2 group IIA (PLA2G2A). Furthermore, downregulation of IL32 results in lower intracellular type I collagen levels in di -lineage human primary hepatic organoids. Finally, we identify a genetic variant of IL32 (rs76580947) associated with lower circulating IL -32 and protection against SLD measured by non-invasive tests. These data suggest that IL32 downregulation may be beneficial against SLD
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