227 research outputs found
Beyond in-phase and anti-phase coordination in a model of joint action
In 1985, Haken, Kelso and Bunz proposed a system of coupled nonlinear oscillators as a model of rhythmic movement patterns in human bimanual coordination. Since then, the Haken–Kelso–Bunz (HKB) model has become a modelling paradigm applied extensively in all areas of movement science, including interpersonal motor coordination. However, all previous studies have followed a line of analysis based on slowly varying amplitudes and rotating wave approximations. These approximations lead to a reduced system, consisting of a single differential equation representing the evolution of the relative phase of the two coupled oscillators: the HKB model of the relative phase. Here we take a different approach and systematically investigate the behaviour of the HKB model in the full four-dimensional state space and for general coupling strengths. We perform detailed numerical bifurcation analyses and reveal that the HKB model supports previously unreported dynamical regimes as well as bistability between a variety of coordination patterns. Furthermore, we identify the stability boundaries of distinct coordination regimes in the model and discuss the applicability of our findings to interpersonal coordination and other joint action tasks
Don’t make me angry, you wouldn’t like me when I’m angry: volitional choices to act or inhibit are modulated by subliminal perception of emotional faces
Volitional action and self-control—feelings of acting according to one’s own intentions and in being control of one’s own actions—are fundamental aspects of human conscious experience. However, it is unknown whether high-level cognitive control mechanisms are affected by socially salient but nonconscious emotional cues. In this study, we manipulated free choice decisions to act or withhold an action by subliminally presenting emotional faces: In a novel version of the Go/NoGo paradigm, participants made speeded button-press responses to Go targets, withheld responses to NoGo targets, and made spontaneous, free choices to execute or withhold the response for Choice targets. Before each target, we presented emotional faces, backwards masked to render them nonconscious. In Intentional trials, subliminal angry faces made participants more likely to voluntarily withhold the action, whereas fearful and happy faces had no effects. In a second experiment, the faces were made supraliminal, which eliminated the effects of angry faces on volitional choices. A third experiment measured neural correlates of the effects of subliminal angry faces on intentional choice using EEG. After replicating the behavioural results found in Experiment 1, we identified a frontal-midline theta component—associated with cognitive control processes—which is present for volitional decisions, and is modulated by subliminal angry faces. This suggests a mechanism whereby subliminally presented “threat” stimuli affect conscious control processes. In summary, nonconscious perception of angry faces increases choices to inhibit, and subliminal influences on volitional action are deep seated and ecologically embedded
Limited effect of chronic valproic acid treatment in a mouse model of Machado-Joseph disease
Machado-Joseph disease (MJD) is an inherited neurodegenerative disease, caused by a CAG repeat expansion within the coding region of ATXN3 gene, and which currently lacks effective treatment. In this work we tested the therapeutic efficacy of chronic treatment with valproic acid (VPA) (200mg/kg), a compound with known neuroprotection activity, and previously shown to be effective in cell, fly and nematode models of MJD. We show that chronic VPA treatment in the CMVMJD135 mouse model had limited effects in the motor deficits of these mice, seen mostly at late stages in the motor swimming, beam walk, rotarod and spontaneous locomotor activity tests, and did not modify the ATXN3 inclusion load and astrogliosis in affected brain regions. However, VPA chronic treatment was able to increase GRP78 protein levels at 30 weeks of age, one of its known neuroprotective effects, confirming target engagement. In spite of limited results, the use of another dosage of VPA or of VPA in a combined therapy with molecules targeting other pathways, cannot be excluded as potential strategies for MJD therapeuticsPM received funding from Ataxia UK Grant (Project: Pharmacologic therapy for Machado-Joseph disease: from a C. elegans drug screen to a mouse model validation). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.info:eu-repo/semantics/publishedVersio
The <i>Pratylenchus penetrans</i> transcriptome as a source for the development of alternative control strategies:mining for putative genes involved in parasitism and evaluation of <i>in planta</i> RNAi
The root lesion nematode Pratylenchus penetrans is considered one of the most economically important species within the genus. Host range studies have shown that nearly 400 plant species can be parasitized by this species. To obtain insight into the transcriptome of this migratory plant-parasitic nematode, we used Illumina mRNA sequencing analysis of a mixed population, as well as nematode reads detected in infected soybean roots 3 and 7 days after nematode infection. Over 140 million paired end reads were obtained for this species, and de novo assembly resulted in a total of 23,715 transcripts. Homology searches showed significant hit matches to 58% of the total number of transcripts using different protein and EST databases. In general, the transcriptome of P. penetrans follows common features reported for other root lesion nematode species. We also explored the efficacy of RNAi, delivered from the host, as a strategy to control P. penetrans, by targeted knock-down of selected nematode genes. Different comparisons were performed to identify putative nematode genes with a role in parasitism, resulting in the identification of transcripts with similarities to other nematode parasitism genes. Focusing on the predicted nematode secreted proteins found in this transcriptome, we observed specific members to be up-regulated at the early time points of infection. In the present study, we observed an enrichment of predicted secreted proteins along the early time points of parasitism by this species, with a significant number being pioneer candidate genes. A representative set of genes examined using RT-PCR confirms their expression during the host infection. The expression patterns of the different candidate genes raise the possibility that they might be involved in critical steps of P. penetrans parasitism. This analysis sheds light on the transcriptional changes that accompany plant infection by P. penetrans, and will aid in identifying potential gene targets for selection and use to design effective control strategies against root lesion nematodes
Assessing the Effects of the Transition from Multiple Daily Insulin Injections (MDI) to Continuous Subcutaneous Insulin Infusion in the Intensive Treatment of Type 1 Diabetes Mellitus
Introduction: Intensive insulin therapy is currently the main treatment in type I diabetes mellitus (DM) which includes multiple daily insulin injections (MDI) and continuous subcutaneous insulin infusion (CSII). The latter has become the preferred therapeutic mode, since it better mimics the physiological pancreatic action, althought there is limited evidence that supports its superiority to MDI. The aim of our study was to assess the effects of the transition from MDI to CSII in the intensive treatment of type 1 DM. Material and Methods: A retrospective longitudinal study was perfonned in MDI patients that transited to CSII between 2006 and 2014. Data were collected regarding to weight, HbA1c, plasma glucose, lipid profile, creatinine, weekly frequency of episodes of hypoglycemia and hyperglycemia and presence of microvascular complications. The effects of the transition to CSII were also compared according to the following subgroups: pre-CSII HbA1c (7.0%); age ( 35 years); gender (male versus female); BMI (25 kg/m2); duration of illness ( 15 years); total daily dose (TDD) of insulin ( 45 units of insulin); ISF ( 40) and microvascular complications (presence versus absence). Results: The sample included 85 patients, mean age 38 +/- 11 years, 50 (58.8%) female, with duration of the disease 21 +/- 9 years. There was a significant reduction in the frequency of hypo and hyperglycemia events after transition to CSII (3.0 +/- 5.0 vs 2 +/- 2.2 per week, p= 0.001 and 5.5 +/- 6.1 vs 2.5 +/- 2.6 per week, p = 0.05, respectively). We also observed a greater glycemic benefit in the subgroups of patients with poorer metabolic control (HbA1c > 7%) compared to those with HbA1c s <= 7% (Delta HbA1c =-0.55% vs 0.20%, respectively, p < 0.05), for the first 6 months after CSII, being additionally reported a significant increase in HDL-C levels (2.81 +/- 10.34 mg/dL, p = 0.039). Conclusion: In this study, CSII therapy was shown to be more effective compared to MDI in patients with poorer metabolic control, being also noted a significant reduction of weekly frequency of hypo and hyperglycemia events. Notwithstanding the encouraging results linked with CSII, in the future, longer longitudinal studies will be mandatory in order to assess the real relative effectiveness of CSII in the treatment of type 1 DM
An intriguing shift occurs in the novel protein phosphatase 1 binding partner, TCTEX1D4: evidence of positive selection in a pika model
T-complex testis expressed protein 1 domain containing 4 (TCTEX1D4) contains the canonical phosphoprotein phosphatase 1 (PPP1) binding motif, composed by the amino acid sequence RVSF. We identified and validated the binding of TCTEX1D4 to PPP1 and demonstrated that indeed this protein is a novel PPP1 interacting protein. Analyses of twenty-one mammalian species available in public databases and seven Lagomorpha sequences obtained in this work showed that the PPP1 binding motif 90RVSF93 is present in all of them and is flanked by a palindromic sequence, PLGS, except in three species of pikas (Ochotona princeps, O. dauurica and O. pusilla). Furthermore, for the Ochotona species an extra glycosylation site, motif 96NLS98, and the loss of the palindromic sequence were observed. Comparison with other lagomorphs suggests that this event happened before the Ochotona radiation. The dN/dS for the sequence region comprising the PPP1 binding motif and the flanking palindrome highly supports the hypothesis that for Ochotona species this region has been evolving under positive selection. In addition, mutational screening shows that the ability of pikas TCTEX1D4 to bind to PPP1 is maintained, although the PPP1 binding motif is disrupted, and the N- and C-terminal surrounding residues are also abrogated. These observations suggest pika as an ideal model to study novel PPP1 complexes regulatory mechanisms.publishe
Emotional Voice and Emotional Body Postures Influence Each Other Independently of Visual Awareness
Multisensory integration may occur independently of visual attention as previously shown with compound face-voice stimuli. We investigated in two experiments whether the perception of whole body expressions and the perception of voices influence each other when observers are not aware of seeing the bodily expression. In the first experiment participants categorized masked happy and angry bodily expressions while ignoring congruent or incongruent emotional voices. The onset between target and mask varied from −50 to +133 ms. Results show that the congruency between the emotion in the voice and the bodily expressions influences audiovisual perception independently of the visibility of the stimuli. In the second experiment participants categorized the emotional voices combined with masked bodily expressions as fearful or happy. This experiment showed that bodily expressions presented outside visual awareness still influence prosody perception. Our experiments show that audiovisual integration between bodily expressions and affective prosody can take place outside and independent of visual awareness
INTESTINAL AND PULMONARY INFECTION BY Cryptosporidium parvum IN TWO PATIENTS WITH HIV/AIDS
We describe two patients with HIV/AIDS who presented pulmonary and intestinal infection caused by Cryptosporidium parvum, with a fatal outcome. The lack of available description of changes in clinical signs and radiographic characteristics of this disease when it is located in the extra-intestinal region causes low prevalence of early diagnosis and a subsequent lack of treatment
Cellular and Molecular Mechanisms Underlying the Strong Neonatal IL-12 Response of Lamb Mesenteric Lymph Node Cells to R-848
International audienceabsen
- …
