807 research outputs found
Mirroring and making sense of others
the parieto-frontal mirror circuit: interpretations
and misinterpretations. Nature Rev.
Neurosci. 11, 264\u2013274 (2010))1, Giacomo
Rizzolatti and I were aiming to highlight the
functional role of the parieto-frontal mirror
network in understanding the actions and
intentions of others. Leonhard Schilbach has
recently argued (A second-person approach
to other minds. Nature Rev. Neurosci. 20
May 2010 (doi: 10.1038/nrn2805-c1))2 that,
although \u201cwell balanced\u201d, the Review does
not take into account the enactive approach
to social cognition and so overlooks the fundamental
difference between being directly
engaged in interaction with someone else
(that is, having a second-person perspective)
and merely observing others (assuming a
third-person perspective). In this reply I argue that Schildbach''s criticism
is misleading to characterize the mirror-based
action and intention understanding as a
pure third-person grasp of other individuals\u2019
mental states that is performed in a mere
observational \u2014 that is, detached \u2014 stance, as it
fails to appreciate the full implications
of the discovery of the mirror system
Looking ahead: anticipatory gaze and motor ability in infancy
The present study asks when infants are able to selectively anticipate the goals of observed actions, and how this ability relates to infants' own abilities to produce those specific actions. Using eye-tracking technology to measure on-line anticipation, 6-, 8- and 10-month-old infants and a control group of adults were tested while observing an adult reach with a whole hand grasp, a precision grasp or a closed fist towards one of two different sized objects. The same infants were also given a comparable action production task. All infants showed proactive gaze to the whole hand grasps, with increased degrees of proactivity in the older groups. Gaze proactivity to the precision grasps, however, was present from 8 months of age. Moreover, the infants' ability in performing precision grasping strongly predicted their ability in using the actor's hand shape cues to differentially anticipate the goal of the observed action, even when age was partialled out. The results are discussed in terms of the specificity of action anticipation, and the fine-grained relationship between action production and action perception
Use of Chitosan to Prolong Mozzarella Cheese Shelf Life
This study was undertaken to evaluate the feasibility of using chitosan, a natural antimicrobial substance, to improve the preservation of a very perishable cheese. The effectiveness of chitosan to inhibit the growth of spoilage microorganisms in Mozzarella cheese was studied during refrigerated storage. A lactic acid/chitosan solution was added directly to the starter used for Mozzarella cheese manufacturing. Mozzarella cheese samples were stored at 4 degrees C for about 10 d and microbial populations as well as the pH were monitored. Results demonstrated that chitosan inhibited the growth of some spoilage microorganisms such as coliforms, whereas it did not influence the growth of other microorganisms, such as Micrococcaceae, and lightly stimulated lactic acid bacteria
The functional role of the parieto-frontal mirror circuit: interpretations and misinterpretations
The parieto-frontal cortical circuit that is active during action observation is the
circuit with mirror properties that has been most extensively studied. Yet, there remains
controversy on its role in social cognition and its contribution to understanding the actions
and intentions of other individuals. Recent studies in monkeys and humans have shed light
on what the parieto-frontal cortical circuit encodes and its possible functional relevance for
cognition. We conclude that, although there are several mechanisms through which one can
understand the behaviour of other individuals, the parieto-frontal mechanism is the only one
that allows an individual to understand the action of others \u2018from the inside\u2019 and gives the
observer a first-person grasp of the motor goals and intentions of other individuals
Mechanisms of HIV-1 Nucleocapsid Protein Inhibition by Lysyl-Peptidyl-Anthraquinone Conjugates
The Nucleocapsid protein NCp7 (NC) is a nucleic acid chaperone responsible for essential steps of the HIV-1 life cycle and an attractive candidate for drug development. NC destabilizes nucleic acid structures and promotes the formation of annealed substrates for HIV-1 reverse transcription elongation. Short helical nucleic acid segments bordered by bulges and loops, such as the Trans-Activation Response element (TAR) of HIV-1 and its complementary sequence (cTAR), are nucleation elements for helix destabilization by NC and also preferred recognition sites for threading intercalators. Inspired by these observations, we have recently demonstrated that 2,6-disubstituted peptidylanthraquinone-conjugates inhibit the chaperone activities of recombinant NC in vitro, and that inhibition correlates with the stabilization of TAR and cTAR stem-loop structures. We describe here enhanced NC inhibitory activity by novel conjugates that exhibit longer peptidyl chains ending with a conserved Nterminal lysine. Their efficient inhibition of TAR/cTAR annealing mediated by NC originates from the combination of at least three different mechanisms, namely, their stabilizing effects on nucleic acids dynamics by threading intercalation, their ability to target TAR RNA substrate leading to a direct competition with the protein for the same binding sites on TAR, and, finally, their effective binding to the NC protein. Our results suggest that these molecules may represent the stepping-stone for the future development of NC-inhibitors capable of targeting the protein itself and its recognition site in RNA
Increase of acidification of synthetic brines by ultrasound-treated Lactiplantibacillus plantarum strains isolated from olives
This paper focused on the evaluation of Ultrasound effect on the growth patterns (3â6% of salt and 45 °C), acidification (pH-decrease), interactions with microorganisms, and membrane permeability of nine strains of Lactiplantibacillus plantarum. Ultrasound treatment was applied at 20% of net power by modulating duration (2â10 min) and pulses (2â10 s). Viable count (7.15â8.16 log CFU/mL) was never affected by Ultrasound, while the treatment increased the extent of pH decrease of at least three strains (109, 162 and c19). L. plantarum c19 was the best performer, as a low intensity treatment was able to increase its acidification, without affecting its growth. The effects could be attributed to an increased permeability of the cellular membrane, as suggested by the increase of released intracellular components. Other factors should be further assessed (e.g. possible changes in the metabolism) and the performances of Ultrasound-treated strains in real brines
Ultrasonic modulation of the technological and functional properties of yeast strains
This research was aimed at studying the effects of low intensity ultrasound (US) on some technological and functional properties of eight strains of Saccharomyces cerevisiae; namely, growth patterns (growth at 2â5% of NaCl or at 37 °C), autoaggregation and tolerance to simulated gastrointestinal conditions were evaluated. A US treatment was applied at 20% of net power (130 W) by a modulating duration (2â10 min) and pulses (2â10 s). The viable count (4.81â6.33 log CFU/mL) was not affected by US, while in terms of technological traits the effect was strain specific; in particular, for some strains a positive effect of US was found with a significant growth enhancement (growth index >120%). The treatment was also able to increase the autoaggregation of some strains, thus suggesting that US could represent a promising way to treat and select nonconventional functional yeasts for food applications
A cnidarian homologue of an insect gustatory receptor functions in developmental body patterning.
Insect gustatory and odorant receptors (GRs and ORs) form a superfamily of novel transmembrane proteins, which are expressed in chemosensory neurons that detect environmental stimuli. Here we identify homologues of GRs (Gustatory receptor-like (Grl) genes) in genomes across Protostomia, Deuterostomia and non-Bilateria. Surprisingly, two Grls in the cnidarian Nematostella vectensis, NvecGrl1 and NvecGrl2, are expressed early in development, in the blastula and gastrula, but not at later stages when a putative chemosensory organ forms. NvecGrl1 transcripts are detected around the aboral pole, considered the equivalent to the head-forming region of Bilateria. Morpholino-mediated knockdown of NvecGrl1 causes developmental patterning defects of this region, leading to animals lacking the apical sensory organ. A deuterostome Grl from the sea urchin Strongylocentrotus purpuratus displays similar patterns of developmental expression. These results reveal an early evolutionary origin of the insect chemosensory receptor family and raise the possibility that their ancestral role was in embryonic development
Specific detection of dengue and Zika virus antibodies using envelope proteins with mutations in the conserved fusion loop
Detection of antibodies is widely used for the diagnosis of infections with arthropod-borne flaviviruses including dengue (DENV) and Zika virus (ZIKV). Due to the emergence of ZIKV in areas endemic for DENV, massive co-circulation is observed and methods to specifically diagnose these infections and differentiate them from each other are mandatory. However, serological assays for flaviviruses in general, and for DENV and ZIKV in particular, are compromised by the high degree of similarities in their proteins which can lead to cross-reacting antibodies and false-positive test results. Cross-reacting flavivirus antibodies mainly target the highly conserved fusion loop (FL) domain in the viral envelope (E-) protein, and we and others have shown previously that recombinant E-proteins bearing FL-mutations strongly reduce cross-reactivity. Here we investigate whether such mutant E-proteins can be used to specifically detect antibodies against DENV and ZIKV in an ELISA-format. IgM antibodies against DENV and ZIKV virus were detected with 100% and 94.2% specificity and 90.7% and 87.5% sensitivity, respectively. For IgG the mutant E-proteins showed cross-reactivity, which was overcome by pre-incubation of the sera with the heterologous antigen. This resulted in specificities of 97.1% and 97.9% and in sensitivities of 100% and 100% for the DENV and ZIKV antigens, respectively. Our results suggest that E-proteins bearing mutations in the FL-domain have a high potential for the development of serological DENV and ZIKV tests with high specificity
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