CirdoX: an On/Off-line Multisource Speech and Sound Analysis Software

International audienceVocal User Interfaces in domestic environments recently gained interest in the speech processing community. This interest is due to the opportunity of using it in the framework of Ambient Assisted Living both for home automation (vocal command) and for call for help in case of distress situations, i.e. after a fall. CIRDOX, which is a modular software, is able to analyse online the audio environment in a home, to extract the uttered sentences and then to process them thanks to an ASR module. Moreover, this system perfoms non-speech audio event classification; in this case, specific models must be trained. The software is designed to be modular and to process on-line the audio multichannel stream. Some exemples of studies in which CIRDOX was involved are described. They were operated in real environment, namely a Living lab environment. Keywords: audio and speech processing, natural language and multimodal interactions, Ambient Assisted Living (AAL)

Regulated internalization of NMDA receptors drives PKD1-mediated suppression of the activity of residual cell-surface NMDA receptors

Abstract Background Constitutive and regulated internalization of cell surface proteins has been extensively investigated. The regulated internalization has been characterized as a principal mechanism for removing cell-surface receptors from the plasma membrane, and signaling to downstream targets of receptors. However, so far it is still not known whether the functional properties of remaining (non-internalized) receptor/channels may be regulated by internalization of the same class of receptor/channels. The N-methyl-D-aspartate receptor (NMDAR) is a principal subtype of glutamate-gated ion channel and plays key roles in neuronal plasticity and memory functions. NMDARs are well-known to undergo two types of regulated internalization – homologous and heterologous, which can be induced by high NMDA/glycine and DHPG, respectively. In the present work, we investigated effects of regulated NMDAR internalization on the activity of residual cell-surface NMDARs and neuronal functions. Results In electrophysiological experiments we discovered that the regulated internalization of NMDARs not only reduced the number of cell surface NMDARs but also caused an inhibition of the activity of remaining (non-internalized) surface NMDARs. In biochemical experiments we identified that this functional inhibition of remaining surface NMDARs was mediated by increased serine phosphorylation of surface NMDARs, resulting from the activation of protein kinase D1 (PKD1). Knockdown of PKD1 did not affect NMDAR internalization but prevented the phosphorylation and inhibition of remaining surface NMDARs and NMDAR-mediated synaptic functions. Conclusion These data demonstrate a novel concept that regulated internalization of cell surface NMDARs not only reduces the number of NMDARs on the cell surface but also causes an inhibition of the activity of remaining surface NMDARs through intracellular signaling pathway(s). Furthermore, modulating the activity of remaining surface receptors may be an effective approach for treating receptor internalization-induced changes in neuronal functions of the CNS

Hippocampal protein kinase D1 is necessary for DHPG-induced learning and memory impairments in rats

<div><p>Background</p><p>Understanding molecular mechanisms underlying the induction of learning and memory impairments remains a challenge. Recent investigations have shown that the activation of group I mGluRs (mGluR1 and mGluR5) in cultured hippocampal neurons by application of (<i>S</i>)-3,5-Dihydroxyphenylglycine (DHPG) causes the regulated internalization of N-methyl-D-aspartate receptors (NMDARs), which subsequently activates protein kinase D1 (PKD1). Through phosphorylating the C-terminals of the NMDAR GluN2 subunits, PKD1 down-regulates the activity of remaining (non-internalized) surface NMDARs. The knockdown of PKD1 does not affect the DHPG-induced inhibition of AMPA receptor-mediated miniature excitatory post-synaptic currents (mEPSCs) but prevents the DHPG-induced inhibition of NMDAR-mediated mEPSCs <i>in vitro</i>. Thus, we investigated the <i>in vivo</i> effects of bilateral infusions of DHPG into the hippocampal CA1 area of rats in the Morris water maze (MWM) and the novel object discrimination (NOD) tests.</p><p>Methods</p><p>A total of 300 adult male Sprague Dawley rats (250–280 g) were used for behavioral tests. One hundred ninety four were used in MWM test and the other 106 rats in the NOD test. Following one week of habituation to the vivarium, rats were bilaterally implanted under deep anesthesia with cannulas aimed at the CA1 area of the hippocampus (CA1 coordinates in mm from Bregma: AP -3.14; lateral +/-2; DV -3.0). Through implanted cannulas artificial cerebrospinal fluid (ACSF), the group1 mGluR antagonist 6-Methyl-2-(phenylethynyl)pyridine (MPEP), the dynamin-dependent internalization inhibitor Dynasore, or the PKD1 inhibitor CID755673 were infused into the bilateral hippocampal CA1 areas (2 μL per side, over 5 min). The effects of these infusions and the effects of PKD1 knockdown were examined in MWM or NOD test.</p><p>Results</p><p>DHPG infusion increased the latency to reach the platform in the MWM test and reduced the preference for the novel object in the NOD task. We found that the DHPG effects were dose-dependent and could be maintained for up to 2 days. Notably, these effects could be prevented by pre-infusion of the group1 mGluR antagonist MPEP, the dynamin-dependent internalization inhibitor Dynasore, the PKD1 inhibitor CID755673, or by PKD1 knockdown in the hippocampal CA1 area.</p><p>Conclusion</p><p>Altogether, these findings provide direct evidence that PKD1-mediated signaling may play a critical role in the induction of learning and memory impairments by DHPG infusion into the hippocampal CA1 area.</p></div

Dose-dependent changes in spatial memory induced by DHPG infusion.

<p>Bar graphs in <b>A, B, C</b> and <b>D</b> respectively show the summary data (mean ± SEM) of the averaged swimming speed, latency and the percentages of swimming distances and time within the goal quadrant relative to the total swimming distance and time before (open bar) and after the infusion of ACSF or 0.5, 5, 50 or 100 μmol DHPG as indicated (Closed bar) in the MWM performance test. *: <i>p</i> < 0.05, **: <i>p</i> < 0.01, ****: <i>p</i> < 0.0001 (paired <i>t</i>-test) in comparison with that before the infusion. See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0195095#pone.0195095.s003" target="_blank">S2 Table</a> for statistical details; Values in the brackets indicate the number of rats tested.</p

Impairments of spatial memory induced by bilateral infusions of DHPG (50 μmol) into the CA1 area.

<p><b>A</b> shows swimming track plots of a rat in the MWM performance test in a training session at day 1 (left) and day 5 before (middle) and after (right) the infusion of DHPG (50 μmol) into the bilateral CA1 areas, respectively. Arrow indicates the intra-CA1 infusion of DHPG. Stars indicate where the rat was put into the pool; white circles indicate the position of a platform in the third quadrant (Q3, the goal quadrant) and 2 cm below the water level. Black squares indicate the final locations of the rat. The summary data (mean ± SEM) of the latency from when rats were released into the pool to reaching the platform, the averaged swimming speed, the percentages of swimming distance and time within the goal quadrant relative to the total swimming distance and time are shown in <b>B</b>, <b>C</b>, <b>D</b> and <b>E</b>, respectively. Open triangles indicate the performance of non-operated rats. Arrows indicate the infusion of ACSF (open circles) or DHPG (filled circles) into the bilateral CA1 areas. *: <i>p</i> < 0.05, **: <i>p</i> < 0.01. ***: <i>p</i> < 0.001, ****: <i>p</i> < 0.0001 (paired <i>t</i>-test) in comparisons with that before the infusion at day 5 in the ACSF or DHPG group, or with that of the first performance of MWM at day 5 in non-operated rats; #: <i>p</i> < 0.05, ##: <i>p</i> < 0.01, ####: <i>p</i> < 0.0001 (Bonferroni post hoc test in repeated measures two-way ANOVA) in comparison with those of the non-operated group; $: <i>p</i> < 0.05,$ $: <i>p</i> < 0.01,$ $$: <i>p</i> < 0.001, $$ $$: <i>p</i> < 0.0001 (Bonferroni post hoc test in repeated measures two-way ANOVA) in comparison with those of the ACSF group. See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0195095#pone.0195095.s002" target="_blank">S1 Table</a> for statistical details; Values in the brackets indicate the number of rats tested.</p

General locomotion, anxiety, and investigative behaviors of rats tested for the DHPG effects.

<p>The general locomotor activity and anxiety levels of rats undergoing the NOD task was first tested in the empty arena during an open-field session. The total distance moved (<b>A</b>), speed (<b>B</b>), time in center (<b>C</b>), as well as the time spent in all four corners of the arena (<b>D</b>) were thus quantified in rats that would be infused with ACSF or DHPG, after pre-infusion of Dynasore or its vehicle [Vehicle (D)]. Furthermore, the total time spent interacting with either objects during the sample phase and the test phase of the NOD task is depicted in <b>E</b>. See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0195095#pone.0195095.s005" target="_blank">S4 Table</a> for statistical details; Values in the brackets indicate the number of rats tested.</p

Pre-infusion of MPEP or CID755673 prevented impairments of spatial memory induced by DHPG infusion.

<p>Bar graphs in <b>A</b>, <b>B</b>, <b>C</b> and <b>D</b> show the summary data (mean ± SEM) of the averaged swimming speed, latency, and percentage values of the swim distance and time in the goal quadrant versus the total swimming distance and time of rats in the MWM test. Bar graphs in <b>E</b> and <b>F</b> show the summary data (mean ± SEM) of the percentage values of the swimming time spent in the goal quadrant, and the number of times crossing the location of the platform in the probe test. Rats received two infusions of chemicals through implanted cannulas in the bilateral CA1 areas as indicated. The second infusion was conducted 10 min after the completion of the first one. The MWM test was performed 5 min after the second infusion. ACSF+ACSF: receiving two infusions of ACSF; ACSF+DHPG: receiving infusions of ACSF followed by DHPG (50 μmol); ACSF+CID: receiving infusions of ACSF followed by CID755673 (182 nmol); MPEP+DHPG: receiving infusions of MPEP (10 μmol) followed by DHPG (50 μmol); CID+DHPG: receiving infusions of CID755673 (182 nmol) followed by DHPG (50 μmol). **: <i>p</i> < 0.01, ****: <i>p</i> < 0.0001 (paired <i>t</i>-test) in comparison with that before the pre-infusion; #: <i>p</i> < 0.05, ###: <i>p</i> < 0.0001 (unpaired <i>t</i>-test) in comparison with rats received ACSF+ACSF. See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0195095#pone.0195095.s004" target="_blank">S3 Table</a> for statistical details; Values in brackets indicate number of animals tested.</p

Effects of bilateral infusion of DHPG (50 μmol/2 μL) into the CA1 area on the NOD performance.

<p>The preference for the novel object is represented by the time spent interacting with the novel object as a percentage of the total time spent interacting with objects in <b>A</b> for rats following the infusion of ACSF or DHPG into the CA1 area without (Control, left two bars in <b>A</b>) or with co-application of vehicle of Dynasore (middle two bars in <b>A</b>) or Dynasore (80 μmol, right two bars in <b>A</b>). Blots in <b>B</b> show examples of Western blot analysis of PKD1 (upper blots) and GAPDH proteins (lower blots) in the CA1 area in rats which received the infusion of control siRNA (Ctl. siRNA) or PKD1 siRNA in this area. Summary data of the ratios of band intensities of PKD1 versus GAPDH proteins (= 100%) are shown in the bar graphs in <b>B</b>. Bar graphs in <b>C</b> show the preference for the novel object—represented by the time spent interacting with the novel object as a percentage of the total time spent interacting with objects—of rats following intra-CA1 infusion of ACSF (open bars) or DHPG (filled bars) pre-administrated with PKD1 siRNA or control siRNA. #: <i>p</i> < 0.05 (unpaired t-test); See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0195095#pone.0195095.s006" target="_blank">S5 Table</a> for statistical details; Values in brackets indicate the number of animals tested.</p

Schematics of experimental procedures.

<p>Implanted cannulas aimed at the CA1 area of the hippocampus was verified (see arrowheads) on brain section as shown in <b>A</b>. Timelines of the infusion performance in MWM test are shown in <b>B</b>, <b>C</b> and <b>D</b>. Following the recovery for 3 days from the surgery, rats were trained for MWM performance test for 5 consecutive days (see <b>B</b>, <b>C</b> and <b>D</b>). Open arrowheads in <b>B</b>, <b>C</b> and <b>D</b> indicate MWM training before the infusion, and closed arrowheads indicate testing after the infusion. Timelines of the infusion performance in NOD test are shown <b>E, F</b> and <b>G</b>. Arrowheads in <b>E, F</b> and <b>G</b> show the infusion of chemicals as indicated. siRNA: PKD1 siRNA or control siRNA; Euthanized: the animals tested were sacrificed for sampling the tissues of the hippocampal CA1 area; OFT: Open-field test; Veh-Dyn: vehicle of Dynasore; Dyn: Dynasore.</p