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Sample records for modulate rhythmic body

  1. Growth and body composition in Brazilian female rhythmic gymnastics athletes.

    PubMed

    Camargo, Cristiane Teixeira Amaral; Gomez-Campos, Rossana Anelice; Cossio-Bolaños, Marco Antonio; Barbeta, Vinicius Justino De Oliveira; Arruda, Miguel; Guerra-Junior, Gil

    2014-01-01

    The aim was to analyse the physical growth and body composition of rhythmic gymnastics athletes relative to their level of somatic maturation. This was a cross-sectional study of 136 athletes on 23 teams from Brazil. Mass, standing height and sitting height were measured. Fat-free and fat masses, body fat percentages and ages of the predicted peak height velocity (PHV) were calculated. The z scores for mass were negative during all ages according to both WHO and Brazilian references, and that for standing height were also negative for all ages according to WHO reference but only until 12 years old according to Brazilian reference. The mean age of the predicted PHV was 12.1 years. The mean mass, standing and sitting heights, body fat percentage, fat-free mass and fat mass increased significantly until 4 to 5 years after the age of the PHV. Menarche was reached in only 26% of these athletes and mean age was 13.2 years. The mass was below the national reference standards, and the standing height was below only for the international reference, but they also had late recovery of mass and standing height during puberty. In conclusion, these athletes had a potential to gain mass and standing height several years after PHV, indicating late maturation.

  2. Distributed Attention Is Implemented through Theta-Rhythmic Gamma Modulation.

    PubMed

    Landau, Ayelet Nina; Schreyer, Helene Marianne; van Pelt, Stan; Fries, Pascal

    2015-08-31

    When subjects monitor a single location, visual target detection depends on the pre-target phase of an ∼8 Hz brain rhythm. When multiple locations are monitored, performance decrements suggest a division of the 8 Hz rhythm over the number of locations, indicating that different locations are sequentially sampled. Indeed, when subjects monitor two locations, performance benefits alternate at a 4 Hz rhythm. These performance alternations were revealed after a reset of attention to one location. Although resets are common and important events for attention, it is unknown whether, in the absence of resets, ongoing attention samples stimuli in alternation. Here, we examined whether spatially specific attentional sampling can be revealed by ongoing pre-target brain rhythms. Visually induced gamma-band activity plays a role in spatial attention. Therefore, we hypothesized that performance on two simultaneously monitored stimuli can be predicted by a 4 Hz modulation of gamma-band activity. Brain rhythms were assessed with magnetoencephalography (MEG) while subjects monitored bilateral grating stimuli for a unilateral target event. The corresponding contralateral gamma-band responses were subtracted from each other to isolate spatially selective, target-related fluctuations. The resulting lateralized gamma-band activity (LGA) showed opposite pre-target 4 Hz phases for detected versus missed targets. The 4 Hz phase of pre-target LGA accounted for a 14.5% modulation in performance. These findings suggest that spatial attention is a theta-rhythmic sampling process that is continuously ongoing, with each sampling cycle being implemented through gamma-band synchrony.

  3. Bone Mineralization in Rhythmic Gymnasts Entering Puberty: Associations with Jumping Performance and Body Composition Variables

    PubMed Central

    Võsoberg, Kristel; Tillmann, Vallo; Tamm, Anna-Liisa; Maasalu, Katre; Jürimäe, Jaak

    2017-01-01

    This study examined bone mineral density (BMD) accrual in prepubertal rhythmic gymnasts entering puberty and their age-matched untrained control girls, and associations with baseline jumping performance and body composition over the 3-year period. Whole body (WB) and femoral neck (FN) BMD, WB fat mass (FM) and fat free mass (FFM), countermovement jump (CMJ) and rebound jumps for 15 s (RJ15s) were assessed in 25 rhythmic gymnasts and 25 untrained controls at baseline and after 3-year period. The changes over this period were calculated (Δ scores). Pubertal maturation over the 3-year period was slower in rhythmic gymnasts compared to untrained controls, while no difference in bone age development was seen. WB BMD increased similarly in both groups, while the increase in FN BMD was higher in rhythmic gymnasts compared with untrained controls. In rhythmic gymnasts, baseline FFM was the most significant predictor of ΔWB BMD explaining 19.2% of the variability, while baseline RJ15s was the most significant predictor of ΔFN BMD explaining 18.5% of the variability. In untrained controls, baseline FM explained 51.8 and 18.9% of the variability in ΔWB BMD and ΔFN BMD, respectively. In conclusion, mechanical loading of high-intensity athletic activity had beneficial effect on BMD accrual in rhythmic gymnasts and may have counterbalanced such negative factors on bone development as slower pubertal maturation and lower body FM. Baseline FFM and repeated jumps test performance were related to BMD accrual in rhythmic gymnasts, while baseline FM was related to BMD accrual in untrained controls. Key points Sudy examined bone mineralization in prepubertal rhythmic gymnasts entering puberty and their age-matched untrained control girls, and associations with baseline jumping performance and body composition. Jumping performance and fat free mass values predicted bone mineral accrual in rhythmic gymnasts. Fat mass predicted bone mineral accrual in untrained control girls

  4. Hearing What the Body Feels: Auditory Encoding of Rhythmic Movement

    ERIC Educational Resources Information Center

    Phillips-Silver, Jessica; Trainor, Laurel J.

    2007-01-01

    Phillips-Silver and Trainor (Phillips-Silver, J., Trainor, L.J., (2005). Feeling the beat: movement influences infants' rhythm perception. "Science", 308, 1430) demonstrated an early cross-modal interaction between body movement and auditory encoding of musical rhythm in infants. Here we show that the way adults move their bodies to music…

  5. Subliminal stimuli modulate somatosensory perception rhythmically and provide evidence for discrete perception

    PubMed Central

    Baumgarten, Thomas J.; Königs, Sara; Schnitzler, Alfons; Lange, Joachim

    2017-01-01

    Despite being experienced as continuous, there is an ongoing debate if perception is an intrinsically discrete process, with incoming sensory information treated as a succession of single perceptual cycles. Here, we provide causal evidence that somatosensory perception is composed of discrete perceptual cycles. We used in humans an electrotactile temporal discrimination task preceded by a subliminal (i.e., below perceptual threshold) stimulus. Although not consciously perceived, subliminal stimuli are known to elicit neuronal activity in early sensory areas and modulate the phase of ongoing neuronal oscillations. We hypothesized that the subliminal stimulus indirectly, but systematically modulates the ongoing oscillatory phase in S1, thereby rhythmically shaping perception. The present results confirm that, without being consciously perceived, the subliminal stimulus critically influenced perception in the discrimination task. Importantly, perception was modulated rhythmically, in cycles corresponding to the beta-band (13–18 Hz). This can be compellingly explained by a model of discrete perceptual cycles. PMID:28276493

  6. EEG Oscillations Are Modulated in Different Behavior-Related Networks during Rhythmic Finger Movements.

    PubMed

    Seeber, Martin; Scherer, Reinhold; Müller-Putz, Gernot R

    2016-11-16

    Sequencing and timing of body movements are essential to perform motoric tasks. In this study, we investigate the temporal relation between cortical oscillations and human motor behavior (i.e., rhythmic finger movements). High-density EEG recordings were used for source imaging based on individual anatomy. We separated sustained and movement phase-related EEG source amplitudes based on the actual finger movements recorded by a data glove. Sustained amplitude modulations in the contralateral hand area show decrease for α (10-12 Hz) and β (18-24 Hz), but increase for high γ (60-80 Hz) frequencies during the entire movement period. Additionally, we found movement phase-related amplitudes, which resembled the flexion and extension sequence of the fingers. Especially for faster movement cadences, movement phase-related amplitudes included high β (24-30 Hz) frequencies in prefrontal areas. Interestingly, the spectral profiles and source patterns of movement phase-related amplitudes differed from sustained activities, suggesting that they represent different frequency-specific large-scale networks. First, networks were signified by the sustained element, which statically modulate their synchrony levels during continuous movements. These networks may upregulate neuronal excitability in brain regions specific to the limb, in this study the right hand area. Second, movement phase-related networks, which modulate their synchrony in relation to the movement sequence. We suggest that these frequency-specific networks are associated with distinct functions, including top-down control, sensorimotor prediction, and integration. The separation of different large-scale networks, we applied in this work, improves the interpretation of EEG sources in relation to human motor behavior.

  7. Local modulation of human brain responses by circadian rhythmicity and sleep debt.

    PubMed

    Muto, Vincenzo; Jaspar, Mathieu; Meyer, Christelle; Kussé, Caroline; Chellappa, Sarah L; Degueldre, Christian; Balteau, Evelyne; Shaffii-Le Bourdiec, Anahita; Luxen, André; Middleton, Benita; Archer, Simon N; Phillips, Christophe; Collette, Fabienne; Vandewalle, Gilles; Dijk, Derk-Jan; Maquet, Pierre

    2016-08-12

    Human performance is modulated by circadian rhythmicity and homeostatic sleep pressure. Whether and how this interaction is represented at the regional brain level has not been established. We quantified changes in brain responses to a sustained-attention task during 13 functional magnetic resonance imaging sessions scheduled across the circadian cycle, during 42 hours of wakefulness and after recovery sleep, in 33 healthy participants. Cortical responses showed significant circadian rhythmicity, the phase of which varied across brain regions. Cortical responses also significantly decreased with accrued sleep debt. Subcortical areas exhibited primarily a circadian modulation that closely followed the melatonin profile. These findings expand our understanding of the mechanisms involved in maintaining cognition during the day and its deterioration during sleep deprivation and circadian misalignment.

  8. Modulation of Rhythmic Activity in Mammalian Spinal Networks Is Dependent on Excitability State

    PubMed Central

    2017-01-01

    Neuromodulators play an important role in activating rhythmically active motor networks; however, what remains unclear are the network interactions whereby neuromodulators recruit spinal motor networks to produce rhythmic activity. Evidence from invertebrate systems has demonstrated that the effect of neuromodulators depends on the pre-existing state of the network. We explored how network excitation state affects the ability of dopamine to evoke rhythmic locomotor activity in the neonatal mouse isolated spinal cord. We found that dopamine can evoke unique patterns of motor activity that are dependent on the excitability state of motor networks. Different patterns of motor activity ranging from tonic, nonrhythmic activity to multirhythmic, nonlocomotor activity to locomotor activity were produced by altering global motor network excitability through manipulations of the extracellular potassium and bath NMDA concentration. A similar effect was observed when network excitation was manipulated during an unstable multirhythm evoked by a low concentration (15 µm) of 5-HT, suggesting that our results are not neuromodulator specific. Our data show in vertebrate systems that modulation is a two-way street and that modulatory actions are largely influenced by the network state. The level of network excitation can account for variability between preparations and is an additional factor to be considered when circuit elements are removed from the network. PMID:28144626

  9. Mechanisms underlying rhythmic locomotion: body-fluid interaction in undulatory swimming.

    PubMed

    Chen, J; Friesen, W O; Iwasaki, T

    2011-02-15

    Swimming of fish and other animals results from interactions of rhythmic body movements with the surrounding fluid. This paper develops a model for the body-fluid interaction in undulatory swimming of leeches, where the body is represented by a chain of rigid links and the hydrodynamic force model is based on resistive and reactive force theories. The drag and added-mass coefficients for the fluid force model were determined from experimental data of kinematic variables during intact swimming, measured through video recording and image processing. Parameter optimizations to minimize errors in simulated model behaviors revealed that the resistive force is dominant, and a simple static function of relative velocity captures the essence of hydrodynamic forces acting on the body. The model thus developed, together with the experimental kinematic data, allows us to investigate temporal and spatial (along the body) distributions of muscle actuation, body curvature, hydrodynamic thrust and drag, muscle power supply and energy dissipation into the fluid. We have found that: (1) thrust is generated continuously along the body with increasing magnitude toward the tail, (2) drag is nearly constant along the body, (3) muscle actuation waves travel two or three times faster than the body curvature waves and (4) energy for swimming is supplied primarily by the mid-body muscles, transmitted through the body in the form of elastic energy, and dissipated into the water near the tail.

  10. Unpredicted Pitch Modulates Beta Oscillatory Power during Rhythmic Entrainment to a Tone Sequence

    PubMed Central

    Chang, Andrew; Bosnyak, Dan J.; Trainor, Laurel J.

    2016-01-01

    Extracting temporal regularities in external stimuli in order to predict upcoming events is an essential aspect of perception. Fluctuations in induced power of beta band (15–25 Hz) oscillations in auditory cortex are involved in predictive timing during rhythmic entrainment, but whether such fluctuations are affected by prediction in the spectral (frequency/pitch) domain remains unclear. We tested whether unpredicted (i.e., unexpected) pitches in a rhythmic tone sequence modulate beta band activity by recording EEG while participants passively listened to isochronous auditory oddball sequences with occasional unpredicted deviant pitches at two different presentation rates. The results showed that the power in low-beta (15–20 Hz) was larger around 200–300 ms following deviant tones compared to standard tones, and this effect was larger when the deviant tones were less predicted. Our results suggest that the induced beta power activities in auditory cortex are consistent with a role in sensory prediction of both “when” (timing) upcoming sounds will occur as well as the prediction precision error of “what” (spectral content in this case). We suggest, further, that both timing and content predictions may co-modulate beta oscillations via attention. These findings extend earlier work on neural oscillations by investigating the functional significance of beta oscillations for sensory prediction. The findings help elucidate the functional significance of beta oscillations in perception. PMID:27014138

  11. Modulation of cortical excitability and interhemispheric inhibition prior to rhythmic unimanual contractions.

    PubMed

    Sharples, Simon A; Kalmar, Jayne M

    2012-09-30

    The objective of this study was to investigate premotor modulation of motor cortical excitability between rhythmic unimanual finger contractions. Applying TMS at rest prior to an anticipated contraction provides a measure of cortical excitability that reflects premotor modulatory drive and is uncontaminated by the alterations in spinal and cortical excitability that occur during muscle activation. We hypothesized that premotor structures contribute to unimanual movement through the modulation of intracortical and interhemispheric inhibitory circuits within the primary motor cortex and that this premotor modulation would be evident at rest between contractions. Thus, we used transcranial magnetic stimulation (TMS) to assess short interval intracortical inhibition (SICI) and interhemispheric inhibition (IHI) in a 500-ms epoch prior to a planned contraction of the right FDI in 10 participants (21.4±1.9 years). These measures of inhibition were made in three different states: (1) at complete rest (with no plan to contract), (2) at rest between rhythmic contractions, and (3) during low level contractions. Cortical excitability was enhanced prior to a contraction and during a contraction compared to at rest (F₂,₁₈=758.3, p<0.001). IHI was also increased prior to a contraction compared to at rest and during a contraction while SICI was only reduced during a contraction (F₂,₃₈=30.3, p<0.001).We used this pre-contraction protocol to investigate the cortical mechanisms of unimanual control. However, this protocol would be a useful tool to investigate any neuromuscular adaptation that may occur as a result of altered premotor modulation of cortical excitability, such as neuromuscular fatigue, training and movement disorders.

  12. Content congruency and its interplay with temporal synchrony modulate integration between rhythmic audiovisual streams

    PubMed Central

    Su, Yi-Huang

    2014-01-01

    Both lower-level stimulus factors (e.g., temporal proximity) and higher-level cognitive factors (e.g., content congruency) are known to influence multisensory integration. The former can direct attention in a converging manner, and the latter can indicate whether information from the two modalities belongs together. The present research investigated whether and how these two factors interacted in the perception of rhythmic, audiovisual (AV) streams derived from a human movement scenario. Congruency here was based on sensorimotor correspondence pertaining to rhythm perception. Participants attended to bimodal stimuli consisting of a humanlike figure moving regularly to a sequence of auditory beat, and detected a possible auditory temporal deviant. The figure moved either downwards (congruently) or upwards (incongruently) to the downbeat, while in both situations the movement was either synchronous with the beat, or lagging behind it. Greater cross-modal binding was expected to hinder deviant detection. Results revealed poorer detection for congruent than for incongruent streams, suggesting stronger integration in the former. False alarms increased in asynchronous stimuli only for congruent streams, indicating greater tendency for deviant report due to visual capture of asynchronous auditory events. In addition, a greater increase in perceived synchrony was associated with a greater reduction in false alarms for congruent streams, while the pattern was reversed for incongruent ones. These results demonstrate that content congruency as a top-down factor not only promotes integration, but also modulates bottom-up effects of synchrony. Results are also discussed regarding how theories of integration and attentional entrainment may be combined in the context of rhythmic multisensory stimuli. PMID:25538576

  13. Physiological modules for generating discrete and rhythmic movements: component analysis of EMG signals.

    PubMed

    Bengoetxea, Ana; Leurs, Françoise; Hoellinger, Thomas; Cebolla, Ana Maria; Dan, Bernard; Cheron, Guy; McIntyre, Joseph

    2014-01-01

    A central question in Neuroscience is that of how the nervous system generates the spatiotemporal commands needed to realize complex gestures, such as handwriting. A key postulate is that the central nervous system (CNS) builds up complex movements from a set of simpler motor primitives or control modules. In this study we examined the control modules underlying the generation of muscle activations when performing different types of movement: discrete, point-to-point movements in eight different directions and continuous figure-eight movements in both the normal, upright orientation and rotated 90°. To test for the effects of biomechanical constraints, movements were performed in the frontal-parallel or sagittal planes, corresponding to two different nominal flexion/abduction postures of the shoulder. In all cases we measured limb kinematics and surface electromyographic activity (EMG) signals for seven different muscles acting around the shoulder. We first performed principal component analysis (PCA) of the EMG signals on a movement-by-movement basis. We found a surprisingly consistent pattern of muscle groupings across movement types and movement planes, although we could detect systematic differences between the PCs derived from movements performed in each shoulder posture and between the principal components associated with the different orientations of the figure. Unexpectedly we found no systematic differences between the figure eights and the point-to-point movements. The first three principal components could be associated with a general co-contraction of all seven muscles plus two patterns of reciprocal activation. From these results, we surmise that both "discrete-rhythmic movements" such as the figure eight, and discrete point-to-point movement may be constructed from three different fundamental modules, one regulating the impedance of the limb over the time span of the movement and two others operating to generate movement, one aligned with the

  14. Diel rhythmicity of lipid-body formation in a coral- Symbiodinium endosymbiosis

    NASA Astrophysics Data System (ADS)

    Chen, W.-N. U.; Kang, H.-J.; Weis, V. M.; Mayfield, A. B.; Jiang, P.-L.; Fang, L.-S.; Chen, C.-S.

    2012-06-01

    The biogenesis of intracellular lipid bodies (LBs) is dependent upon the symbiotic status between host corals and their intracellular dinoflagellates (genus Symbiodinium), though aside from this observation, little is known about LB behavior and function in this globally important endosymbiosis. The present research aimed to understand how LB formation and density are regulated in the gastrodermal tissue layer of the reef-building coral Euphyllia glabrescens. After tissue fixation and labeling with osmium tetroxide, LB distribution and density were quantified by imaging analysis of serial cryo-sections, and a diel rhythmicity was observed; the onset of solar irradiation at sunrise initiated an increase in LB density and size, which peaked at sunset. Both LB density and size then decreased to basal levels at night. On a seasonal timescale, LB density was found to be significantly positively correlated with seasonal irradiation, with highest densities found in the summer and lowest in the fall. In terms of LB lipid composition, only the concentration of wax esters, and not triglycerides or sterols, exhibited diel variability. This suggests that the metabolism and accumulation of lipids in LBs is at least partially light dependent. Ultrastructural examinations revealed that the LB wax ester concentration correlated with the number of electron-transparent inclusion bodies. Finally, there was a directional redistribution of the LB population across the gastroderm over the diel cycle. Collectively, these data reveal that coral gastrodermal LBs vary in composition and intracellular location over diel cycles, features which may shed light on their function within this coral-dinoflagellate mutualism.

  15. Laminar profile of spontaneous and evoked theta: Rhythmic modulation of cortical processing during word integration.

    PubMed

    Halgren, Eric; Kaestner, Erik; Marinkovic, Ksenija; Cash, Sydney S; Wang, Chunmao; Schomer, Donald L; Madsen, Joseph R; Ulbert, Istvan

    2015-09-01

    Theta may play a central role during language understanding and other extended cognitive processing, providing an envelope for widespread integration of participating cortical areas. We used linear microelectrode arrays in epileptics to define the circuits generating theta in inferotemporal, perirhinal, entorhinal, prefrontal and anterior cingulate cortices. In all locations, theta was generated by excitatory current sinks in middle layers which receive predominantly feedforward inputs, alternating with sinks in superficial layers which receive mainly feedback/associative inputs. Baseline and event-related theta were generated by indistinguishable laminar profiles of transmembrane currents and unit-firing. Word presentation could reset theta phase, permitting theta to contribute to late event-related potentials, even when theta power decreases relative to baseline. Limited recordings during sentence reading are consistent with rhythmic theta activity entrained by a given word modulating the neural background for the following word. These findings show that theta occurs spontaneously, and can be momentarily suppressed, reset and synchronized by words. Theta represents an alternation between feedforward/divergent and associative/convergent processing modes that may temporally organize sustained processing and optimize the timing of memory formation. We suggest that words are initially encoded via a ventral feedforward stream which is lexicosemantic in the anteroventral temporal lobe; its arrival may trigger a widespread theta rhythm which integrates the word within a larger context.

  16. Physiological modules for generating discrete and rhythmic movements: action identification by a dynamic recurrent neural network.

    PubMed

    Bengoetxea, Ana; Leurs, Françoise; Hoellinger, Thomas; Cebolla, Ana M; Dan, Bernard; McIntyre, Joseph; Cheron, Guy

    2014-01-01

    In this study we employed a dynamic recurrent neural network (DRNN) in a novel fashion to reveal characteristics of control modules underlying the generation of muscle activations when drawing figures with the outstretched arm. We asked healthy human subjects to perform four different figure-eight movements in each of two workspaces (frontal plane and sagittal plane). We then trained a DRNN to predict the movement of the wrist from information in the EMG signals from seven different muscles. We trained different instances of the same network on a single movement direction, on all four movement directions in a single movement plane, or on all eight possible movement patterns and looked at the ability of the DRNN to generalize and predict movements for trials that were not included in the training set. Within a single movement plane, a DRNN trained on one movement direction was not able to predict movements of the hand for trials in the other three directions, but a DRNN trained simultaneously on all four movement directions could generalize across movement directions within the same plane. Similarly, the DRNN was able to reproduce the kinematics of the hand for both movement planes, but only if it was trained on examples performed in each one. As we will discuss, these results indicate that there are important dynamical constraints on the mapping of EMG to hand movement that depend on both the time sequence of the movement and on the anatomical constraints of the musculoskeletal system. In a second step, we injected EMG signals constructed from different synergies derived by the PCA in order to identify the mechanical significance of each of these components. From these results, one can surmise that discrete-rhythmic movements may be constructed from three different fundamental modules, one regulating the co-activation of all muscles over the time span of the movement and two others elliciting patterns of reciprocal activation operating in orthogonal directions.

  17. A common neural element receiving rhythmic arm and leg activity as assessed by reflex modulation in arm muscles.

    PubMed

    Sasada, Syusaku; Tazoe, Toshiki; Nakajima, Tsuyoshi; Futatsubashi, Genki; Ohtsuka, Hiroyuki; Suzuki, Shinya; Zehr, E Paul; Komiyama, Tomoyoshi

    2016-04-01

    Neural interactions between regulatory systems for rhythmic arm and leg movements are an intriguing issue in locomotor neuroscience. Amplitudes of early latency cutaneous reflexes (ELCRs) in stationary arm muscles are modulated during rhythmic leg or arm cycling but not during limb positioning or voluntary contraction. This suggests that interneurons mediating ELCRs to arm muscles integrate outputs from neural systems controlling rhythmic limb movements. Alternatively, outputs could be integrated at the motoneuron and/or supraspinal levels. We examined whether a separate effect on the ELCR pathways and cortico-motoneuronal excitability during arm and leg cycling is integrated by neural elements common to the lumbo-sacral and cervical spinal cord. The subjects performed bilateral leg cycling (LEG), contralateral arm cycling (ARM), and simultaneous contralateral arm and bilateral leg cycling (A&L), while ELCRs in the wrist flexor and shoulder flexor muscles were evoked by superficial radial (SR) nerve stimulation. ELCR amplitudes were facilitated by cycling tasks and were larger during A&L than during ARM and LEG. A low stimulus intensity during ARM or LEG generated a larger ELCR during A&L than the sum of ELCRs during ARM and LEG. We confirmed this nonlinear increase in single motor unit firing probability following SR nerve stimulation during A&L. Furthermore, motor-evoked potentials following transcranial magnetic and electrical stimulation did not show nonlinear potentiation during A&L. These findings suggest the existence of a common neural element of the ELCR reflex pathway that is active only during rhythmic arm and leg movement and receives convergent input from contralateral arms and legs.

  18. A little elastic for a better performance: kinesiotaping of the motor effector modulates neural mechanisms for rhythmic movements

    PubMed Central

    Bravi, Riccardo; Quarta, Eros; Cohen, Erez J.; Gottard, Anna; Minciacchi, Diego

    2014-01-01

    A rhythmic motor performance is brought about by an integration of timing information with movements. Investigations on the millisecond time scale distinguish two forms of time control, event-based timing and emergent timing. While event-based timing asserts the existence of a central internal timekeeper for the control of repetitive movements, the emergent timing perspective claims that timing emerges from dynamic control of nontemporal movements parameters. We have recently demonstrated that the precision of an isochronous performance, defined as performance of repeated movements having a uniform duration, was insensible to auditory stimuli of various characteristics (Bravi et al., 2014). Such finding has led us to investigate whether the application of an elastic therapeutic tape (Kinesio® Tex taping; KTT) used for treating athletic injuries and a variety of physical disorders, is able to reduce the timing variability of repetitive rhythmic movement. Young healthy subjects, tested with and without KTT, have participated in sessions in which sets of repeated isochronous wrist's flexion-extensions (IWFEs) were performed under various auditory conditions and during their recall. Kinematics was recorded and temporal parameters were extracted and analyzed. Our results show that the application of KTT decreases the variability of rhythmic movements by a 2-fold effect: on the one hand KTT provides extra proprioceptive information activating cutaneous mechanoreceptors, on the other KTT biases toward the emergent timing thus modulating the processes for rhythmic movements. Therefore, KTT appears able to render movements less audio dependent by relieving, at least partially, the central structures from time control and making available more resources for an augmented performance. PMID:25309355

  19. Circadian Rhythmicity of Active GSK3 Isoforms Modulates Molecular Clock Gene Rhythms in the Suprachiasmatic Nucleus

    PubMed Central

    Besing, R.C.; Paul, J.R.; Hablitz, L.M.; Rogers, C.O.; Johnson, R.L.; Young, M.E.; Gamble, K.L.

    2015-01-01

    The suprachiasmatic nucleus (SCN) drives and synchronizes daily rhythms at the cellular level via transcriptional-translational feedback loops comprised of clock genes such as Bmal1 and Period (Per). Glycogen synthase kinase 3 (GSK3), a serine/threonine kinase, phosphorylates at least five core clock proteins and shows diurnal variation in phosphorylation state (inactivation) of the GSK3β isoform. Whether phosphorylation of the other primary isoform (GSK3α) varies across the subjective day-night cycle is unknown. The purpose of this study was to determine if the endogenous rhythm of GSK3 (α and β) phosphorylation is critical for rhythmic BMAL1 expression and normal amplitude and periodicity of the molecular clock in the SCN. Significant circadian rhythmicity of phosphorylated GSK3 (α and β) was observed in the SCN from wild-type mice housed in constant darkness for two weeks. Importantly, chronic activation of both GSK3 isoforms impaired rhythmicity of the GSK3 target BMAL1. Furthermore, chronic pharmacological inhibition of GSK3 with 20 μM CHIR-99021 enhanced the amplitude and shortened the period of PER2::luciferase rhythms in organotypic SCN slice cultures. These results support the model that GSK3 activity status is regulated by the circadian clock and that GSK3 feeds back to regulate the molecular clock amplitude in the SCN. PMID:25724980

  20. Modulation of reflex responses in hand muscles during rhythmical finger tasks in a subject with writer's cramp.

    PubMed

    Xia, Ruiping; Bush, Brian M H

    2007-03-01

    The objective of this study was to examine phase- and task-dependent modulation of stretch reflexes during repetitive finger movements in writer's cramp, and compare them with normal controls from our previous study. A subject with writer's cramp conducted two rhythmic tasks, index finger abduction (RFA) and a pen-squeezing (RPS) task akin to handwriting. Stretch reflexes were evoked by mechanical perturbations at random phases of each task. Surface electromyograms (EMG) were recorded from two hand muscles, first dorsal interosseous (FDI) and flexor digitorum superficialis (FDS). The reflex response and background EMG activity of each muscle were modulated in a phase-dependent manner in both tasks. However, they varied largely in phase during the RFA task, but in approximately inverse phase-relationship during RPS. Reflex sensitivity, as represented by the slope of the linear regression between response and background, was much lower for both muscles in the 'writing' task (RPS) than in the RFA task with its positively correlated responses. These phase- and task-related modulation patterns differed dramatically from those observed in our control subjects, where reflex responses were modulated largely in phase with background activity and reflex sensitivity was much higher, particularly in FDI during RFA and FDS during RPS. The altered reflex modulation patterns in writer's cramp may reflect deficiencies of integration of proprioceptive afferent inputs and reduced inhibition at cortical and spinal levels during writing performance. Results from this case study support clinically identified task-specific feature of focal hand dystonia.

  1. Mechanisms underlying rhythmic locomotion: interactions between activation, tension and body curvature waves.

    PubMed

    Chen, Jun; Friesen, W Otto; Iwasaki, Tetsuya

    2012-01-15

    Undulatory animal locomotion arises from three closely related propagating waves that sweep rostrocaudally along the body: activation of segmental muscles by motoneurons (MNs), strain of the body wall, and muscle tension induced by activation and strain. Neuromechanical models that predict the relative propagation speeds of neural/muscle activation, muscle tension and body curvature can reveal crucial underlying control features of the central nervous system and the power-generating mechanisms of the muscle. We provide an analytical explanation of the relative speeds of these three waves based on a model of neuromuscular activation and a model of the body-fluid interactions for leech anguilliform-like swimming. First, we deduced the motoneuron spike frequencies that activate the muscle and the resulting muscle tension during swimming in intact leeches from muscle bending moments. Muscle bending moments were derived from our video-recorded kinematic motion data by our body-fluid interaction model. The phase relationships of neural activation and muscle tension in the strain cycle were then calculated. Our study predicts that the MN activation and body curvature waves have roughly the same speed (the ratio of curvature to MN activation speed ≈0.84), whereas the tension wave travels about twice as fast. The high speed of the tension wave resulting from slow MN activation is explained by the multiplicative effects of MN activation and muscle strain on tension development. That is, the product of two slower waves (activation and strain) with appropriate amplitude, bias and phase can generate a tension wave with twice the propagation speed of the factors. Our study predicts that (1) the bending moment required for swimming is achieved by minimal MN spike frequency, rather than by minimal muscle tension; (2) MN activity is greater in the mid-body than in the head and tail regions; (3) inhibitory MNs not only accelerate the muscle relaxation but also reduce the intrinsic

  2. Arterial CO2 Fluctuations Modulate Neuronal Rhythmicity: Implications for MEG and fMRI Studies of Resting-State Networks

    PubMed Central

    Whittaker, Joseph R.; Bright, Molly G.; Muthukumaraswamy, Suresh D.; Murphy, Kevin

    2016-01-01

    A fast emerging technique for studying human resting state networks (RSNs) is based on spontaneous temporal fluctuations in neuronal oscillatory power, as measured by magnetoencephalography. However, it has been demonstrated recently that this power is sensitive to modulations in arterial CO2 concentration. Arterial CO2 can be modulated by natural fluctuations in breathing pattern, as might typically occur during the acquisition of an RSN experiment. Here, we demonstrate for the first time the fine-scale dependence of neuronal oscillatory power on arterial CO2 concentration, showing that reductions in alpha, beta, and gamma power are observed with even very mild levels of hypercapnia (increased arterial CO2). We use a graded hypercapnia paradigm and participant feedback to rule out a sensory cause, suggesting a predominantly physiological origin. Furthermore, we demonstrate that natural fluctuations in arterial CO2, without administration of inspired CO2, are of a sufficient level to influence neuronal oscillatory power significantly in the delta-, alpha-, beta-, and gamma-frequency bands. A more thorough understanding of the relationship between physiological factors and cortical rhythmicity is required. In light of these findings, existing results, paradigms, and analysis techniques for the study of resting-state brain data should be revisited. SIGNIFICANCE STATEMENT In this study, we show for the first time that neuronal oscillatory power is intimately linked to arterial CO2 concentration down to the fine-scale modulations that occur during spontaneous breathing. We extend these results to demonstrate a correlation between neuronal oscillatory power and spontaneous arterial CO2 fluctuations in awake humans at rest. This work identifies a need for studies investigating resting-state networks in the human brain to measure and account for the impact of spontaneous changes in arterial CO2 on the neuronal signals of interest. Changes in breathing pattern that are

  3. Modulation of the mandibular stretch reflex sensitivity during various phases of rhythmic open-close movements in humans.

    PubMed

    van der Bilt, A; Ottenhoff, F A; van der Glas, H W; Bosman, F; Abbink, J H

    1997-04-01

    The muscle spindles of the jaw elevator muscles provide positive feedback to the alpha motoneurons. It is generally assumed that the feedback is modulated during chewing so that counterproductive forces of the jaw elevator muscles can be avoided during jaw opening. Our aim was to investigate the modulation of the muscle spindle input to the alpha motoneurons during various phases of open-close movements in man. To that end, subjects made rhythmic open-close movements at their natural chewing frequency. A force impulse (5 N, 10 ms), eliciting a jaw-jerk reflex, was unexpectedly applied. The impulse was applied to the mandible at 8 different phases during an open-close cycle, but only 1 impulse per cycle. Jaw movement and surface EMG of the masseter and temporal muscles on both sides were recorded during 3 cycles without an impulse and 3 succeeding cycles with an impulse. To examine whether the modulation of the mandibular stretch reflex sensitivity depends on the food resistance, we applied an additional external force on the mandible, counteracting closing of the jaw each cycle. Two experimental sessions were performed in random order, i.e., without force and with an additional force of 20 N. We observed pronounced reflexes at the onset of jaw closing, during the closing phase, and at occlusion. No or only weak jaw-jerk reflexes were present during jaw opening. The reflex amplitudes at occlusion were larger when an external force was present. This increase in reflex amplitude may be the result of an adjusted gamma motoneuron activity, from pre-motor inhibition, or from both. The reflex amplitudes elicited during jaw closing were not correlated with the phase of the movement.

  4. Loss of circadian rhythmicity in body temperature and locomotor activity following suprachiasmatic lesions in the rat

    NASA Technical Reports Server (NTRS)

    Saleh, M. A.; Haro, P. J.; Winget, C. M.

    1977-01-01

    In experiments on male and female ambulatory rats, the effect of bilateral suprachiasmatic lesions on deep body temperature and locomotor activity circadian rhythms was investigated. A L/D:12/12 cycle and 23 C ambient temperature were maintained. One-half of the rats received radiofrequency lesions in the suprachiasmic nucleus (SCN) while the second group were sham operated by lowering the radiofrequency electrode to the SCN without producing electrolytic lesions. Four weeks were allowed for recuperation. Autopsies were conducted to make sure that the lesions were restricted to SCN. The results show the complete disappearance of circadian rhythm in the SCN lesioned rats and only a slight diminution for the sham operated rats.

  5. Expression and Rhythmic Modulation of Circulating MicroRNAs Targeting the Clock Gene Bmal1 in Mice

    PubMed Central

    Shende, Vikram R.; Goldrick, Marianna M.; Ramani, Suchitra; Earnest, David J.

    2011-01-01

    MicroRNAs (miRNAs) interact with 3′ untranslated region (UTR) elements of target genes to regulate mRNA stability or translation and thus play a role in regulating many different biological processes, including circadian rhythms. However, specific miRNAs mediating the regulation of essential clock genes remain largely unknown. Because vesicles containing membrane-bound miRNAs are present in the circulatory system, we examined miRNAs predicted to target the clock gene, Bmal1, for evidence of rhythmic fluctuations in circulating levels and modulatory effects on the 3′ UTR activity of Bmal1. A number of miRNAs with Bmal1 as a predicted target were expressed in the serum of mice exposed to LD 12∶12 and of these miRNAs, miR-152 and miR-494 but not miR-142-3p were marked by diurnal oscillations with bimodal peaks in expression occurring near the middle of the day and 8 or 12 hr later during the night. Co-transfection of pre-miR over-expression constructs for miR-494 and miR-142-3p in HEK293 cells had significant effects in repressing luciferase-reported Bmal1 3′ UTR activity by as much as 60%, suggesting that these miRNAs may function as post-transcriptional modulators of Bmal1. In conjunction with previous studies implicating miRNAs as extracellular regulatory signals, our results suggest that circulating miRNAs may play a role in the regulation of the molecular clockworks in peripheral circadian oscillators. PMID:21799909

  6. Amino-termini isoforms of the Slack K+ channel, regulated by alternative promoters, differentially modulate rhythmic firing and adaptation

    PubMed Central

    Brown, Maile R; Kronengold, Jack; Gazula, Valeswara-Rao; Spilianakis, Charalampos G; Flavell, Richard A; von Hehn, Christian A A; Bhattacharjee, Arin; Kaczmarek, Leonard K

    2008-01-01

    The rates of activation and unitary properties of Na+-activated K+ (KNa) currents have been found to vary substantially in different types of neurones. One class of KNa channels is encoded by the Slack gene. We have now determined that alternative RNA splicing gives rise to at least five different transcripts for Slack, which produce Slack channels that differ in their predicted cytoplasmic amino-termini and in their kinetic properties. Two of these, termed Slack-A channels, contain an amino-terminus domain closely resembling that of another class of KNa channels encoded by the Slick gene. Neuronal expression of Slack-A channels and of the previously described Slack isoform, now called Slack-B, are driven by independent promoters. Slack-A mRNAs were enriched in the brainstem and olfactory bulb and detected at significant levels in four different brain regions. When expressed in CHO cells, Slack-A channels activate rapidly upon depolarization and, in single channel recordings in Xenopus oocytes, are characterized by multiple subconductance states with only brief transient openings to the fully open state. In contrast, Slack-B channels activate slowly over hundreds of milliseconds, with openings to the fully open state that are ∼6-fold longer than those for Slack-A channels. In numerical simulations, neurones in which outward currents are dominated by a Slack-A-like conductance adapt very rapidly to repeated or maintained stimulation over a wide range of stimulus strengths. In contrast, Slack-B currents promote rhythmic firing during maintained stimulation, and allow adaptation rate to vary with stimulus strength. Using an antibody that recognizes all amino-termini isoforms of Slack, Slack immunoreactivity is present at locations that have no Slack-B-specific staining, including olfactory bulb glomeruli and the dendrites of hippocampal neurones, suggesting that Slack channels with alternate amino-termini such as Slack-A channels are present at these locations. Our

  7. Action-perception coordination dynamics of whole-body rhythmic movement in stance: a comparison study of street dancers and non-dancers.

    PubMed

    Miura, Akito; Kudo, Kazutoshi; Nakazawa, Kimitaka

    2013-06-07

    This study investigated whether whole-body, rhythmic action-perception coordination in stance is organized in terms of dynamic principles. We observed whether phase transition and hysteresis occur during the execution of dancing movements. Nine skilled street dancers and 9 novice controls performed 2 types of rhythmic knee-bending movements to a metronome beat in the standing position. Participants performed down-on-the-beat (in which knee flexion coincides with the beat) and up-on-the-beat (in which knee extension coincides with the beat), which are both typical components of street dance. All participants were instructed not to intervene in the pattern change. The auditory stimulus beat rate increased or decreased between 60 and 220 beats per minute (bpm) in steps of 20 bpm. We calculated the phase angle of beat time that is superposed on knee movement trajectory on a phase plane. Under the up-on-the-beat condition, phase transition and hysteresis were observed. The bifurcation frequency at which phase transition occurred significantly differed between groups, indicating that dancers were able to perform up-on-the-beat at higher movement frequencies than non-dancers. This suggests that dynamical properties may differ between Dancers and Non-dancers. The present results provide additional evidence that whole-body action-perception pattern formation is governed by general and common dynamical principles.

  8. Finger posture modulates structural body representations

    PubMed Central

    Tamè, Luigi; Dransfield, Elanah; Quettier, Thomas; Longo, Matthew R.

    2017-01-01

    Patients with lesions of the left posterior parietal cortex commonly fail in identifying their fingers, a condition known as finger agnosia, yet are relatively unimpaired in sensation and skilled action. Such dissociations have traditionally been interpreted as evidence that structural body representations (BSR), such as the body structural description, are distinct from sensorimotor representations, such as the body schema. We investigated whether performance on tasks commonly used to assess finger agnosia is modulated by changes in hand posture. We used the ‘in between’ test in which participants estimate the number of unstimulated fingers between two touched fingers or a localization task in which participants judge which two fingers were stimulated. Across blocks, the fingers were placed in three levels of splay. Judged finger numerosity was analysed, in Exp. 1 by direct report and in Exp. 2 as the actual number of fingers between the fingers named. In both experiments, judgments were greater when non-adjacent stimulated fingers were positioned far apart compared to when they were close together or touching, whereas judgements were unaltered when adjacent fingers were stimulated. This demonstrates that BSRs are not fixed, but are modulated by the real-time physical distances between body parts. PMID:28223685

  9. Short-term effect of whole-body vibration training on balance, flexibility and lower limb explosive strength in elite rhythmic gymnasts.

    PubMed

    Despina, Tsopani; George, Dallas; George, Tsiganos; Sotiris, Papouliakos; Alessandra, Di Cagno; George, Korres; Maria, Riga; Stavros, Korres

    2014-02-01

    The purpose of this study was to examine whether whole-body vibration (WBV) training results in short-term performance improvements in flexibility, strength and balance tests in comparison to an equivalent exercise program performed without vibration. Eleven elite rhythmic gymnasts completed a WBV trial, and a control, resistance training trial without vibration (NWBV). The vibration trial consisted of eccentric and concentric squatting exercises on a vibration platform that was turned on, whereas the NWBV involved the same training protocol with the platform turned off. Balance was assessed using the Rhythmic Weight Shift (RWS) based on the EquiTest Dynamic Posturography system; flexibility was measured using the sit & reach test, and lower limb explosive strength was evaluated using standard exercises (squat jump, counter movement jump, single leg squat). All measurements were performed before (pre) immediately after the training program (post 1), and 15 minutes after the end of the program (post 15). Data were analyzed using repeated measures ANOVA was used with condition (WBV-NWBV) as the primary factor and time (pre, post 1, post 15) as the nested within subjects factor, followed by post-hoc pairwise comparison with Bonferroni corrections. Results confirmed the hypothesis of the superiority of WBV training, especially in the post 15 measurement, in all flexibility and strength measures, as well as in a number of balance tests.

  10. Aperture modulated, translating bed total body irradiation

    SciTech Connect

    Hussain, Amjad; Villarreal-Barajas, Jose Eduardo; Dunscombe, Peter; Brown, Derek W.

    2011-02-15

    Purpose: Total body irradiation (TBI) techniques aim to deliver a uniform radiation dose to a patient with an irregular body contour and a heterogeneous density distribution to within {+-}10% of the prescribed dose. In the current article, the authors present a novel, aperture modulated, translating bed TBI (AMTBI) technique that produces a high degree of dose uniformity throughout the entire patient. Methods: The radiation beam is dynamically shaped in two dimensions using a multileaf collimator (MLC). The irregular surface compensation algorithm in the Eclipse treatment planning system is used for fluence optimization, which is performed based on penetration depth and internal inhomogeneities. Two optimal fluence maps (AP and PA) are generated and beam apertures are created to deliver these optimal fluences. During treatment, the patient/phantom is translated on a motorized bed close to the floor (source to bed distance: 204.5 cm) under a stationary radiation beam with 0 deg. gantry angle. The bed motion and dynamic beam apertures are synchronized. Results: The AMTBI technique produces a more homogeneous dose distribution than fixed open beam translating bed TBI. In phantom studies, the dose deviation along the midline is reduced from 10% to less than 5% of the prescribed dose in the longitudinal direction. Dose to the lung is reduced by more than 15% compared to the unshielded fixed open beam technique. At the lateral body edges, the dose received from the open beam technique was 20% higher than that prescribed at umbilicus midplane. With AMTBI the dose deviation in this same region is reduced to less than 3% of the prescribed dose. Validation of the technique was performed using thermoluminescent dosimeters in a Rando phantom. Agreement between calculation and measurement was better than 3% in all cases. Conclusions: A novel, translating bed, aperture modulated TBI technique that employs dynamically shaped MLC defined beams is shown to improve dose uniformity

  11. Daily Thermal Fluctuations Experienced by Pupae via Rhythmic Nursing Behavior Increase Numbers of Mushroom Body Microglomeruli in the Adult Ant Brain

    PubMed Central

    Falibene, Agustina; Roces, Flavio; Rössler, Wolfgang; Groh, Claudia

    2016-01-01

    Social insects control brood development by using different thermoregulatory strategies. Camponotus mus ants expose their brood to daily temperature fluctuations by translocating them inside the nest following a circadian rhythm of thermal preferences. At the middle of the photophase brood is moved to locations at 30.8°C; 8 h later, during the night, the brood is transferred back to locations at 27.5°C. We investigated whether daily thermal fluctuations experienced by developing pupae affect the neuroarchitecture in the adult brain, in particular in sensory input regions of the mushroom bodies (MB calyces). The complexity of synaptic microcircuits was estimated by quantifying MB-calyx volumes together with densities of presynaptic boutons of microglomeruli (MG) in the olfactory lip and visual collar regions. We compared young adult workers that were reared either under controlled daily thermal fluctuations of different amplitudes, or at different constant temperatures. Thermal regimes significantly affected the large (non-dense) olfactory lip region of the adult MB calyx, while changes in the dense lip and the visual collar were less evident. Thermal fluctuations mimicking the amplitudes of natural temperature fluctuations via circadian rhythmic translocation of pupae by nurses (amplitude 3.3°C) lead to higher numbers of MG in the MB calyces compared to those in pupae reared at smaller or larger thermal amplitudes (0.0, 1.5, 9.6°C), or at constant temperatures (25.4, 35.0°C). We conclude that rhythmic control of brood temperature by nursing ants optimizes brain development by increasing MG densities and numbers in specific brain areas. Resulting differences in synaptic microcircuits are expected to affect sensory processing and learning abilities in adult ants, and may also promote interindividual behavioral variability within colonies. PMID:27147994

  12. Rhythmic 24 h Variation of Core Body Temperature and Locomotor Activity in a Subterranean Rodent (Ctenomys aff. knighti), the Tuco-Tuco

    PubMed Central

    Tachinardi, Patricia; Bicudo, José Eduardo Wilken; Oda, Gisele Akemi; Valentinuzzi, Verónica Sandra

    2014-01-01

    The tuco-tuco Ctenomys aff. knighti is a subterranean rodent which inhabits a semi-arid area in Northwestern Argentina. Although they live in underground burrows where environmental cycles are attenuated, they display robust, 24 h locomotor activity rhythms that are synchronized by light/dark cycles, both in laboratory and field conditions. The underground environment also poses energetic challenges (e.g. high-energy demands of digging, hypoxia, high humidity, low food availability) that have motivated thermoregulation studies in several subterranean rodent species. By using chronobiological protocols, the present work aims to contribute towards these studies by exploring day-night variations of thermoregulatory functions in tuco-tucos, starting with body temperature and its temporal relationship to locomotor activity. Animals showed daily, 24 h body temperature rhythms that persisted even in constant darkness and temperature, synchronizing to a daily light/dark cycle, with highest values occurring during darkness hours. The range of oscillation of body temperature was slightly lower than those reported for similar-sized and dark-active rodents. Most rhythmic parameters, such as period and phase, did not change upon removal of the running wheel. Body temperature and locomotor activity rhythms were robustly associated in time. The former persisted even after removal of the acute effects of intense activity on body temperature by a statistical method. Finally, regression gradients between body temperature and activity were higher in the beginning of the night, suggesting day-night variation in thermal conductance and heat production. Consideration of these day-night variations in thermoregulatory processes is beneficial for further studies on thermoregulation and energetics of subterranean rodents. PMID:24454916

  13. Rhythmic 24 h variation of core body temperature and locomotor activity in a subterranean rodent (Ctenomys aff. knighti), the tuco-tuco.

    PubMed

    Tachinardi, Patricia; Bicudo, José Eduardo Wilken; Oda, Gisele Akemi; Valentinuzzi, Verónica Sandra

    2014-01-01

    The tuco-tuco Ctenomys aff. knighti is a subterranean rodent which inhabits a semi-arid area in Northwestern Argentina. Although they live in underground burrows where environmental cycles are attenuated, they display robust, 24 h locomotor activity rhythms that are synchronized by light/dark cycles, both in laboratory and field conditions. The underground environment also poses energetic challenges (e.g. high-energy demands of digging, hypoxia, high humidity, low food availability) that have motivated thermoregulation studies in several subterranean rodent species. By using chronobiological protocols, the present work aims to contribute towards these studies by exploring day-night variations of thermoregulatory functions in tuco-tucos, starting with body temperature and its temporal relationship to locomotor activity. Animals showed daily, 24 h body temperature rhythms that persisted even in constant darkness and temperature, synchronizing to a daily light/dark cycle, with highest values occurring during darkness hours. The range of oscillation of body temperature was slightly lower than those reported for similar-sized and dark-active rodents. Most rhythmic parameters, such as period and phase, did not change upon removal of the running wheel. Body temperature and locomotor activity rhythms were robustly associated in time. The former persisted even after removal of the acute effects of intense activity on body temperature by a statistical method. Finally, regression gradients between body temperature and activity were higher in the beginning of the night, suggesting day-night variation in thermal conductance and heat production. Consideration of these day-night variations in thermoregulatory processes is beneficial for further studies on thermoregulation and energetics of subterranean rodents.

  14. Emotional modulation of body-selective visual areas

    PubMed Central

    Atkinson, Anthony P.; Andersson, Frederic; Vuilleumier, Patrik

    2007-01-01

    Emotionally expressive faces have been shown to modulate activation in visual cortex, including face-selective regions in ventral temporal lobe. Here, we tested whether emotionally expressive bodies similarly modulate activation in body-selective regions. We show that dynamic displays of bodies with various emotional expressions vs neutral bodies, produce significant activation in two distinct body-selective visual areas, the extrastriate body area and the fusiform body area. Multi-voxel pattern analysis showed that the strength of this emotional modulation was related, on a voxel-by-voxel basis, to the degree of body selectivity, while there was no relation with the degree of selectivity for faces. Across subjects, amygdala responses to emotional bodies positively correlated with the modulation of body-selective areas. Together, these results suggest that emotional cues from body movements produce topographically selective influences on category-specific populations of neurons in visual cortex, and these increases may implicate discrete modulatory projections from the amygdala. PMID:18985133

  15. Bilingual Vocational Training Program. Auto Body Repair. Module 4.0: Auto Body Welding.

    ERIC Educational Resources Information Center

    Northern New Mexico Community Coll., El Rito.

    This module on auto body welding is the fourth of four (CE 028 303-306) in the auto body repair course of a bilingual vocational training program. The course is designed to furnish theoretical and laboratory experience in welding, metal straightening, metal finishing, painting, and use of power and hand tools. Module objectives are for students to…

  16. Bilingual Vocational Training Program. Auto Body Repair. Module 1.0: Beginning Auto Body.

    ERIC Educational Resources Information Center

    Northern New Mexico Community Coll., El Rito.

    This module on beginning auto body is the first of four (CE 028 303-306) in the auto body repair course of a bilingual vocational training program. The course is designed to furnish theoretical and laboratory experience in welding, metal straightening, metal finishing, painting, and use of power and hand tools. Module objectives are for students…

  17. Multiple forms of rhythmic movements in an adolescent boy with rhythmic movement disorder.

    PubMed

    Su, Changjun; Miao, Jianting; Liu, Yu; Liu, Rui; Lei, Gesheng; Zhang, Wei; Yang, Ting; Li, Zhuyi

    2009-12-01

    Rhythmic movement disorder (RMD) refers to a group of stereotyped, repetitive movements involving large muscles, usually occurring prior to the onset of sleep and persisting into sleep. RMD more commonly exhibits only one or two forms of rhythmic movements (RM) in most reported cases. However, multiple RM forms of RMD occurring in a patient in the same night have rarely been reported. In this report, we present the unique case of a 15-year-old boy with RMD affected by multiple forms of RM in the same night, including four known forms (i.e., body rocking, head banging, leg rolling, and rhythmic feet movements) and two new kinds of RM (bilateral rhythmic arm rocking and rhythmic hands movements). Two video-polysomnographic recordings were performed in this patient before starting pharmacologic treatment and after long-term oral clonazepam treatment (1.0mg nightly for 3 months). The characteristics of RMD with multiple RM forms and the effectiveness of clonazepam on the RM episodes and polysomnographic findings observed in our patient are discussed. This report raises the fact that a patient with RMD may present with multiple complex rhythmic movements disrupting sleep, which emphasizes that better understanding of the clinical features of complex rhythmic movements during sleep in primary care settings is essential for early clinical diagnosis and optimal management.

  18. Calculating rhythmicity of infant breathing using wavelets

    NASA Astrophysics Data System (ADS)

    Macey, Katherine E.; Page, Wyatt H.; Harper, Ronald M.; Macey, Paul M.; Ford, Rodney P. K.

    2000-12-01

    Breathing signals are one set of physiological data that may provide information regarding the mechanisms that cause SIDS. Isolated breathing pauses have been implicated in fatal events. Other features of interest include slow amplitude modulation of the breathing signal, a phenomenon whose origin is unclear, and periodic breathing. The latter describes a repetitive series of apnea, and may be considered an extreme manifestation of amplitude modulation with successive cessations of breathing. Rhythmicity is defined to assess the impact of amplitude modulation on breathing signals and describes the extent to which frequency components remain constant for the duration of the signal. The wavelet transform was used to identify sections of constant frequency components within signals. Rhythmicity can be evaluated for all the frequency components in a signal, for individual frequencies. The rhythmicity of eight breathing epochs from sleeping infants at high and low risk for SIDS was calculated. Initial results show breathing from infants at high risk for SIDS exhibits greater rhythmicity of modulating frequencies than breathing from low risk infants.

  19. Teaching Rhythmic Movement to Children: "Chock-Let Pie"

    ERIC Educational Resources Information Center

    Hastie, Peter A.; Martin, Ellen H.; Gibson, Gary S.

    2005-01-01

    It is doubtful that any teacher would question the value of rhythmic movement in a physical education program. The benefits of being able to move rhythmically and to keep a beat are numerous. First, children with rhythm have an increased kinesthetic awareness of their body in motion and stillness. As most physical activities have an inherent…

  20. Guide to "Rhythmically Moving."

    ERIC Educational Resources Information Center

    Carlton, Elizabeth B.; Weikart, Phyllis S.

    This guide accompanies a series of recordings called "Rhythmically Moving." The series of nine recordings is a rare collection of international folk music designed to aid students as they learn to develop basic timing and musicianship. This guide helps the user of the series to receive maximum benefit from the first of the recordings (RM1). Using…

  1. Modulating the rate and rhythmicity of perceptual rivalry alternations with the mixed 5-HT2A and 5-HT1A agonist psilocybin.

    PubMed

    Carter, Olivia L; Pettigrew, John D; Hasler, Felix; Wallis, Guy M; Liu, Guang B; Hell, Daniel; Vollenweider, Franz X

    2005-06-01

    Binocular rivalry occurs when different images are presented simultaneously to corresponding points within the left and right eyes. Under these conditions, the observer's perception will alternate between the two perceptual alternatives. Motivated by the reported link between the rate of perceptual alternations, symptoms of psychosis and an incidental observation that the rhythmicity of perceptual alternations during binocular rivalry was greatly increased 10 h after the consumption of LSD, this study aimed to investigate the pharmacology underlying binocular rivalry and to explore the connection between the timing of perceptual switching and psychosis. Psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine, PY) was chosen for the study because, like LSD, it is known to act as an agonist at serotonin (5-HT)1A and 5-HT2A receptors and to produce an altered state sometimes marked by psychosis-like symptoms. A total of 12 healthy human volunteers were tested under placebo, low-dose (115 microg/kg) and high-dose (250 microg/kg) PY conditions. In line with predictions, under both low- and high-dose conditions, the results show that at 90 min postadministration (the peak of drug action), rate and rhythmicity of perceptual alternations were significantly reduced from placebo levels. Following the 90 min testing period, the perceptual switch rate successively increased, with some individuals showing increases well beyond pretest levels at the final testing, 360 min postadministration. However, as some subjects had still not returned to pretest levels by this time, the mean phase duration at 360 min was not found to differ significantly from placebo. Reflecting the drug-induced changes in rivalry phase durations, subjects showed clear changes in psychological state as indexed by the 5D-ASC (altered states of consciousness) rating scales. This study suggests the involvement of serotonergic pathways in binocular rivalry and supports the previously proposed role of a brainstem

  2. Age modulates attitudes to whole body donation among medical students.

    PubMed

    Perry, Gary F; Ettarh, Raj R

    2009-01-01

    Managing a whole body donor program is necessary for facilitating a traditional dissection-based anatomy curriculum in medicine and health sciences. Factors which influence body donations to medical science can therefore affect dissection-based anatomy teaching. In order to determine whether age influences the attitudes of medical students to donations, this study surveyed, by Likert-type questionnaires, first-year graduate-entry medical students attending a dissection-based anatomy course. In contrast to attitudes among younger traditional-entry medical students, initial support for whole body donation by an unrelated stranger (83.8%), a family member (43.2%) or by the respondent (40.5%) did not decrease among graduate-entry medical students after exposure to dissection although there was a significant shift in strength of support for donation by stranger. This suggests that older medical students do not readily modify their pre-established attitudes to the idea of whole body donation after exposure and experience with dissection. Initial ambivalence among respondents to the idea of donation by family member was followed by opposition to this type of donation. These findings demonstrate that age modulates the influences on a priori attitudes to whole body donation that exposure to dissection causes in younger medical students.

  3. Decisions in motion: passive body acceleration modulates hand choice.

    PubMed

    Bakker, Romy S; Weijer, Roel H A; van Beers, Robert J; Selen, Luc P J; Medendorp, W Pieter

    2017-03-01

    In everyday life, we frequently have to decide which hand to use for a certain action. It has been suggested that for this decision the brain calculates expected costs based on action values, such as expected biomechanical costs, expected success rate, handedness and skillfulness. While these conclusions were based on experiments in stationary subjects, we often act while the body is in motion. We investigated how hand choice is affected by passive body motion, which directly affects the biomechanical costs of the arm movement due to its inertia. Using a linear motion platform, twelve right-handed subjects were sinusoidally translated (0.625Hz and 0.5Hz). At eight possible motion phases, they had to reach using either their left or right hand to a target presented at one of eleven possible locations. We predicted hand choice by calculating the expected biomechanical costs under different assumptions about the future acceleration involved in these computations, being the forthcoming acceleration during the reach, the instantaneous acceleration at target onset or zero acceleration as if the body is stationary. While hand choice was generally biased to using the dominant hand, it also modulated sinusoidally with the motion, with the amplitude of the bias depending on the motion's peak acceleration. The phase of hand choice modulation was consistent with the cost model that took the instantaneous acceleration signal at target onset. This suggest that the brain relies on the bottom-up acceleration signals, and not on predictions about future accelerations, when deciding on hand choice during passive whole-body motion.

  4. Social exclusion modulates pre-reflective interpersonal body representation.

    PubMed

    Ambrosini, Ettore; Blomberg, Olle; Mandrigin, Alisa; Costantini, Marcello

    2014-01-01

    Perception of affordance is enhanced not only when that object is located in one's own peripersonal space, as compared to when it is located within extrapersonal space, but also when the object is located in another person's peripersonal space [as measured by a spatial alignment effect (SAE)]. It has been suggested that this reflects the existence of an interpersonal body representation (IBR) that allows us to represent the perceptual states and action possibilities of others. Here, we address the question of whether IBR can be modulated by higher level/reflective social cognition, such as judgments about one's own social status. Participants responded with either the right or the left hand as soon as a go signal appeared. The go signal screen contained a task-irrelevant stimulus consisting of a 3D scene in which a mug with a left- or right-facing handle was positioned on a table. The mug was positioned either inside or outside the reaching space of the participants. In a third of the trials, the mug was positioned within the reaching space of an avatar seated at the table. Prior to this task we induced an experience of social ostracism in half of the participants by means of a standardized social exclusion condition. The results were that the SAE that normally occurs when the mug is in the avatar's reaching space is extinguished by the induced social exclusion. This indicates that judgments about one's own social status modulate the effect of IBR.

  5. Acute corticospinal and spinal modulation after whole body vibration

    PubMed Central

    Krause, A.; Gollhofer, A.; Freyler, K.; Jablonka, L.; Ritzmann, R.

    2016-01-01

    Objectives: The objective of this study was to investigate neural effects of acute whole body vibration (WBV) on lower limb muscles regarding corticospinal and spinal excitability. Methods: In 44 healthy subjects (16 f/ 28 m), motor evoked potentials (MEP) and H-reflexes in m. soleus (SOL) and gastrocnemius medialis (GM) were elicited before (t1), immediately after (t2), 2 (t3), 4 (t4) and 10 min after (t5) WBV. Results: After WBV, MEP amplitudes were significantly increased in SOL (t2+15±30%, t3+22±32%, t4+15±35%, t5+20±30%, P<0.05), but not in GM (t2+32±62%, t3+9±35%, t4+8±36%, t5+22±47%; P=0.07). Contrarily, H-reflexes were significantly reduced in SOL (t2-19±28%, t3-21±22%, t4-20±21%, t5-14±28%, P<0.05) and GM (t2-14±37%, t3-16±25%, t4-18±29%, t5-16±28%, P<0.05). Conclusions: A temporary sustained enhancement of corticospinal excitability concomitant with spinal inhibition after WBV points towards persisting neural modulation in the central nervous system. This could indicate greater neural modulation over M1 and descending pathways, while the contribution of spinal pathways is reduced. PMID:27973385

  6. The use of many-body physics and thermodynamics to describe the dynamics of rhythmic generators in sensory cortices engaged in memory and learning.

    PubMed

    Vitiello, Giuseppe

    2015-04-01

    The problem of the transition from the molecular and cellular level to the macroscopic level of observed assemblies of myriads of neurons is the subject addressed in this report. The great amount of detailed information available at molecular and cellular level seems not sufficient to account for the high effectiveness and reliability observed in the brain macroscopic functioning. It is suggested that the dissipative many-body model and thermodynamics might offer the dynamical frame underlying the rich phenomenology observed at microscopic and macroscopic level and help in the understanding on how to fill the gap between the bio-molecular and cellular level and the one of brain macroscopic functioning.

  7. Parasomnia with rhythmic movements manifesting as nocturnal tongue biting.

    PubMed

    Tuxhorn, I; Hoppe, M

    1993-06-01

    The case of a healthy 2-year-old girl with repeated nocturnal tongue biting as a result of rhythmic movements of the jaw associated with body rocking in non-REM sleep is described. Parasomnias manifesting with rhythmic, stereotyped movements of the head, trunk and extremities are well described in healthy children. The term rhythmic movement disorders (RMD) was introduced for these repetive movements in sleep which may appear as head banging (jactatio capitis), body rocking or leg rolling. Severe injuries including fractures, subdural effusions and eye injures are reported. Repeated tongue injuries have not been described as a consequence of RMD. The differential diagnosis from nocturnal seizures is crucial to avoid overtreatment of this benign albeit dramatically presenting condition.

  8. Matrix Rigidity-Modulated Cardiovascular Organoid Formation from Embryoid Bodies

    PubMed Central

    Shkumatov, Artem; Baek, Kwanghyun; Kong, Hyunjoon

    2014-01-01

    Stem cell clusters, such as embryoid bodies (EBs) derived from embryonic stem cells, are extensively studied for creation of multicellular clusters and complex functional tissues. It is common to control phenotypes of ES cells with varying molecular compounds; however, there is still a need to improve the controllability of cell differentiation, and thus, the quality of created tissue. This study demonstrates a simple but effective strategy to promote formation of vascularized cardiac muscle - like tissue in EBs and form contracting cardiovascular organoids by modulating the stiffness of a cell adherent hydrogel. Using collagen-conjugated polyacrylamide hydrogels with controlled elastic moduli, we discovered that cellular organization in a form of vascularized cardiac muscle sheet was maximal on the gel with the stiffness similar to cardiac muscle. We envisage that the results of this study will greatly contribute to better understanding of emergent behavior of stem cells in developmental and regeneration process and will also expedite translation of EB studies to drug-screening device assembly and clinical treatments. PMID:24732893

  9. Predictive coding of music--brain responses to rhythmic incongruity.

    PubMed

    Vuust, Peter; Ostergaard, Leif; Pallesen, Karen Johanne; Bailey, Christopher; Roepstorff, Andreas

    2009-01-01

    During the last decades, models of music processing in the brain have mainly discussed the specificity of brain modules involved in processing different musical components. We argue that predictive coding offers an explanatory framework for functional integration in musical processing. Further, we provide empirical evidence for such a network in the analysis of event-related MEG-components to rhythmic incongruence in the context of strong metric anticipation. This is seen in a mismatch negativity (MMNm) and a subsequent P3am component, which have the properties of an error term and a subsequent evaluation in a predictive coding framework. There were both quantitative and qualitative differences in the evoked responses in expert jazz musicians compared with rhythmically unskilled non-musicians. We propose that these differences trace a functional adaptation and/or a genetic pre-disposition in experts which allows for a more precise rhythmic prediction.

  10. Central pattern generators and the control of rhythmic movements.

    PubMed

    Marder, E; Bucher, D

    2001-11-27

    Central pattern generators are neuronal circuits that when activated can produce rhythmic motor patterns such as walking, breathing, flying, and swimming in the absence of sensory or descending inputs that carry specific timing information. General principles of the organization of these circuits and their control by higher brain centers have come from the study of smaller circuits found in invertebrates. Recent work on vertebrates highlights the importance of neuro-modulatory control pathways in enabling spinal cord and brain stem circuits to generate meaningful motor patterns. Because rhythmic motor patterns are easily quantified and studied, central pattern generators will provide important testing grounds for understanding the effects of numerous genetic mutations on behavior. Moreover, further understanding of the modulation of spinal cord circuitry used in rhythmic behaviors should facilitate the development of new treatments to enhance recovery after spinal cord damage.

  11. Effects of rhythmic precursors on perception of stress/syllabicity

    NASA Astrophysics Data System (ADS)

    Stilp, Christian E.; Kluender, Keith R.

    2005-09-01

    Rhythmic structure is a common property of many environmental sounds including speech. Here, perceptual effects of preceding rhythmic context are assessed in experiments employing edited words for which perceived stress/syllabicity are assessed. A series of edited naturally spoken words varying perceptually from ``polite'' to ``plight,'' was created by deleting initial-vowel glottal pulses from a recording of ``polite.'' Words were identified following nonspeech precursor sequences having either trochaic (strong-weak) or iambic (weak-strong) rhythmic patterns. Precursors consisted of a harmonic spectrum (-6-dB/octave slope) filtered by four sinusoidally modulated single-pole filters. Trochaic (strong-weak) and iambic (weak-strong) rhythmic patterns were created by varying amplitude, pitch, and duration in successive segments (akin to beats) of the precursors. Precursors were comprised of two to six repetitions of these patterns. Following trochaic precursors, listeners were more likely to report hearing ``polite'' (iambic). This pattern of results indicates that perception did not assimilate to precursor pattern, consistent with rhythmic expectancy. Instead, perception shifted in a way that contrasts with precursor temporal pattern. Additional results with precursors that are more and less like speech are being conducted to further understand how auditory perception adjusts for temporal and spectral regularities. [Work supported by NIDCD.

  12. Rhythmic movement disorder in childhood: An integrative review.

    PubMed

    Gwyther, Amy R M; Walters, Arthur S; Hill, Catherine M

    2016-08-26

    Rhythmic movement disorder consists of repetitive stereotypic movements, such as head banging or body rocking, that recur every second or so and may last from a few minutes to hours, usually prior to sleep onset. This review of childhood rhythmic movement disorder highlights the lack of systematic research into core aspects of the condition, relying heavily on small case series or case reports. Interpretation is further limited by almost universal failure to confirm the core diagnostic criteria (C) of the International classification of sleep disorders (III), namely that the rhythmic movements should have clinical consequences. Nonetheless, a number of themes emerge. Rhythmic movement disorder is likely to start in infancy and have a developmental course with spontaneous resolution in early childhood in many cases. Factors associated with persistence are, however, unclear. Associations with ADHD and neurodevelopmental disorders are intriguing, require further study and may shed light on the underlying cause of the condition. There is a pressing need for a systematic approach to classify rhythmic movement disorder, to allow standardization of the much needed research into the underlying aetiology and treatment of this relatively neglected sleep disorder.

  13. Some anthropologic factors of performance in rhythmic gymnastics novices.

    PubMed

    Miletić, Durdica; Katić, Ratko; Males, Boris

    2004-12-01

    The aim of the study was to determine motor and morphological factors, and to assess their impact on specific motor skill performance in rhythmic gymnastics (RG). Experimental training process aimed at learning and improving basic movement structures of rhythmic gymnastics was performed for nine months in a sample of 50 female rhythmic gymnastics novices (mean age 7.1 +/- 0.3 years). Seven dimensions in total were isolated by factorial analysis of 13 motor, 11 morphological, and 20 specific rhythmic gymnastics tests. The factors of flexibility (Beta = 0.26; p < 0.05), explosive strength (Beta = 0.25; p < 0.05) and adipose voluminosity (Beta = -0.42; p < 0.001) explains 41% of the success in performing RG basic body elements--jumps, rotations, balance and flexibility (R = 0.64), while the frequency of movement (Beta = 0.44; p < 0.001) and non-adipose voluminosity (Beta = 0.26; p < 0.05) explains 26% of RG-specific manipulations with the apparatus--club, ribbon and ball wrist manipulation (R = 0.52; p < 0.01). According to study results, the RG-training process intended for rhythmic gymnastics novices should be programmed, with preset objectives for the development of flexibility and explosive strength, speed and peripheral joint strength and adipose tissue reduction.

  14. Evidence for Multiple Rhythmic Skills

    PubMed Central

    Tierney, Adam; Kraus, Nina

    2015-01-01

    Rhythms, or patterns in time, play a vital role in both speech and music. Proficiency in a number of rhythm skills has been linked to language ability, suggesting that certain rhythmic processes in music and language rely on overlapping resources. However, a lack of understanding about how rhythm skills relate to each other has impeded progress in understanding how language relies on rhythm processing. In particular, it is unknown whether all rhythm skills are linked together, forming a single broad rhythmic competence, or whether there are multiple dissociable rhythm skills. We hypothesized that beat tapping and rhythm memory/sequencing form two separate clusters of rhythm skills. This hypothesis was tested with a battery of two beat tapping and two rhythm memory tests. Here we show that tapping to a metronome and the ability to adjust to a changing tempo while tapping to a metronome are related skills. The ability to remember rhythms and to drum along to repeating rhythmic sequences are also related. However, we found no relationship between beat tapping skills and rhythm memory skills. Thus, beat tapping and rhythm memory are dissociable rhythmic aptitudes. This discovery may inform future research disambiguating how distinct rhythm competencies track with specific language functions. PMID:26376489

  15. FRAMES User Defined Body Burden Concentration File Module Documentation

    SciTech Connect

    Pelton, Mitchell A.; Rutz, Frederick C.; Eslinger, Melany A.; Gelston, Gariann M.

    2001-06-01

    The Framework for Risk Analysis in Multimedia Environmental Systems (FRAMES) Body Burden Concentration File (BBF) contains time-varying, instantaneous, constituent concentrations for body burden by contaminant. This report contains the requirements for this file and will be used by software engineers and testers to ensure that the file inputs properly.

  16. Age Modulates Attitudes to Whole Body Donation among Medical Students

    ERIC Educational Resources Information Center

    Perry, Gary F.; Ettarh, Raj R.

    2009-01-01

    Managing a whole body donor program is necessary for facilitating a traditional dissection-based anatomy curriculum in medicine and health sciences. Factors which influence body donations to medical science can therefore affect dissection-based anatomy teaching. In order to determine whether age influences the attitudes of medical students to…

  17. Differences between the sexes in technical mastery of rhythmic gymnastics.

    PubMed

    Bozanic, Ana; Miletic, Durdica

    2011-02-01

    The aims of this study were to determine possible differences between the sexes in specific rhythmic gymnastics techniques, and to examine the influence of various aspects of technique on rhythmic composition performance. Seventy-five students aged 21 ± 2 years (45 males, 30 female) undertook four test sessions to determine: coefficients of asymmetry, stability, versatility, and the two rhythmic compositions (without apparatus and with rope). An independent-sample t-test revealed sex-based differences in technique acquisition: stability for ball (P < 0.05; effect size = 0.65) and club (P < 0.05; effect size = 0.79) performance and rhythmic composition without apparatus (P < 0.05; effect size = 0.66). Multiple regression analysis revealed that the variables for assessing stability (beta = 0.44; P < 0.05) and versatility (beta = 0.61; P < 0.05) explained 61% of the variance in the rhythmic composition performance of females, and the variables for assessing asymmetry (beta = -0.38; P < 0.05), versatility (beta = 0.32; P < 0.05), and stability (beta = 0.29; P < 0.05) explained 52% of the variance in the rhythmic composition performance of males. The results suggest that female students dominate in body skill technique, while male students have the advantage with apparatus. There was a lack of an expressive aesthetic component in performance for males. The need for ambidexterity should be considered in the planning of training programmes.

  18. Anatomy and Physiology. Module Set II: Major Body Systems. Teacher Edition [and] Student Edition. Surgical Technology.

    ERIC Educational Resources Information Center

    Hilley, Robert

    This document, which is the second part of a two-part set of modules on anatomy and physiology for future surgical technicians, contains the teacher and student editions of an introduction to anatomy and physiology that consists of modules on the following body systems: integumentary system; skeletal system; muscular system; nervous system;…

  19. Bilingual Vocational Training Program. Auto Body Repair. Module 2.0: Tools and Equipment.

    ERIC Educational Resources Information Center

    Northern New Mexico Community Coll., El Rito.

    This module on tools and equipment is the second of four (CE 028 303-306) in the auto body repair course of a bilingual vocational training program. The course is designed to furnish theoretical and laboratory experience in welding, metal straightening, metal finishing, painting, and use of power and hand tools. Module objectives are for students…

  20. Proprioceptive Body Illusions Modulate the Visual Perception of Reaching Distance

    PubMed Central

    Petroni, Agustin; Carbajal, M. Julia; Sigman, Mariano

    2015-01-01

    The neurobiology of reaching has been extensively studied in human and non-human primates. However, the mechanisms that allow a subject to decide—without engaging in explicit action—whether an object is reachable are not fully understood. Some studies conclude that decisions near the reach limit depend on motor simulations of the reaching movement. Others have shown that the body schema plays a role in explicit and implicit distance estimation, especially after motor practice with a tool. In this study we evaluate the causal role of multisensory body representations in the perception of reachable space. We reasoned that if body schema is used to estimate reach, an illusion of the finger size induced by proprioceptive stimulation should propagate to the perception of reaching distances. To test this hypothesis we induced a proprioceptive illusion of extension or shrinkage of the right index finger while participants judged a series of LEDs as reachable or non-reachable without actual movement. Our results show that reach distance estimation depends on the illusory perceived size of the finger: illusory elongation produced a shift of reaching distance away from the body whereas illusory shrinkage produced the opposite effect. Combining these results with previous findings, we suggest that deciding if a target is reachable requires an integration of body inputs in high order multisensory parietal areas that engage in movement simulations through connections with frontal premotor areas. PMID:26110274

  1. Visual detail about the body modulates tactile localisation biases.

    PubMed

    Margolis, Aaron N; Longo, Matthew R

    2015-02-01

    The localisation of tactile stimuli requires the integration of visual and somatosensory inputs within an internal representation of the body surface and is prone to consistent bias. Joints may play a role in segmenting such internal body representations, and may therefore influence tactile localisation biases, although the nature of this influence remains unclear. Here, we investigate the relationship between conceptual knowledge of joint locations and tactile localisation biases on the hand. In one task, participants localised tactile stimuli applied to the dorsum of their hand. A distal localisation bias was observed in all participants, consistent with previous results. We also manipulated the availability of visual information during this task, to determine whether the absence of this information could account for the distal bias observed here and by Mancini et al. (Neuropsychologia 49:1194-1201, 2011). The observed distal bias increased in magnitude when visual information was restricted, without a corresponding decrease in precision. In a separate task, the same participants indicated, from memory, knuckle locations on a silhouette image of their hand. Analogous distal biases were also seen in the knuckle localisation task. The accuracy of conceptual joint knowledge was not correlated with tactile localisation bias magnitude, although a similarity in observed bias direction suggests that both tasks may rely on a common, higher-order body representation. These results also suggest that distortions of conceptual body representation may be more common in healthy individuals than previously thought.

  2. Somatotype of top-level serbian rhythmic gymnasts.

    PubMed

    Purenović-Ivanović, Tijana; Popović, Ružena

    2014-03-27

    Body size and build influence performance in many sports, especially in those belonging to the group of female aesthetic sports (rhythmic gymnastics, artistic gymnastics, and figure skating). These sports pose high specific demands upon the functional, energy, motor and psychological capacities of athletes, but also upon the size, body build and composition of the performers, particularly of the top-level female athletes. The study of the top athletes (rhythmic gymnasts, in this case) may provide valuable information on the morphological requirements for achieving success in this sport. Therefore, the main objective of this research was to analyze the somatotype of 40 Serbian top-level rhythmic gymnasts, aged 13.04±2.79, and to form the five age group categories. The anthropometric variables included body height, body mass, the selected diameters, girths and skinfolds, and the Heath-Carter anthropometric somatotype. All of the anthropometric data were collected according to International Biological Programme, and then processed in the Somatotype 1.2. The applied analysis of variance indicated an increase in endomorphic component with age. The obtained results show that the balanced ectomorph is a dominant somatotype, being similar for all of the athletes that took part in the research (3.54-3.24-4.5). These results are in line with the ones obtained in previous studies.

  3. Romantic love modulates women's identification of men's body odors.

    PubMed

    Lundström, Johan N; Jones-Gotman, Marilyn

    2009-02-01

    Romantic love is one of our most potent and powerful emotions, but very little is known with respect to the hormonal and psychological mechanisms in play. Romantic love is thought to help intimate partners stay committed to each other and two mechanisms have been proposed to mediate this commitment: increased attention towards one's partner or deflected attention away from other potential partners. Both mechanisms find support in the literature. We explored the potential influence of each of these mechanisms by assessing women's ability to identify (ID) body odors originating from their boyfriend, a same-sex friend, and an opposite-sex friend and the relationship between this ability and the degree of romantic love expressed towards their boyfriend. We hypothesized that an increase in attention towards one's partner would render a positive correlation between ID of a boyfriend's body odor and degree of romantic love; conversely, we hypothesized that attention deflected away from other potential partners would render a negative correlation between ID of an opposite-sex friend's body odor and degree of romantic love for the boyfriend. Our results supported the deflection theory as we found a negative correlation between the degree of romantic love for the subjects' boyfriends and their ability to ID the body odor of an opposite-sex friend but not of their boyfriend or same-sex friend. Our results indicate that romantic love deflects attention away from potential new partners rather than towards the present partner. These changes are likely mediated by circulating neuropeptides and a testable model is suggested.

  4. Excitability changes in human forearm corticospinal projections and spinal reflex pathways during rhythmic voluntary movement of the opposite limb

    PubMed Central

    Carson, R G; Riek, S; Mackey, D C; Meichenbaum, D P; Willms, K; Forner, M; Byblow, W D

    2004-01-01

    Rhythmic movements brought about by the contraction of muscles on one side of the body give rise to phase-locked changes in the excitability of the homologous motor pathways of the opposite limb. Such crossed facilitation should favour patterns of bimanual coordination in which homologous muscles are engaged simultaneously, and disrupt those in which the muscles are activated in an alternating fashion. In order to examine these issues, we obtained responses to transcranial magnetic stimulation (TMS), to stimulation of the cervicomedullary junction (cervicomedullary-evoked potentials, CMEPs), to peripheral nerve stimulation (H-reflexes and f-waves), and elicited stretch reflexes in the relaxed right flexor carpi radialis (FCR) muscle during rhythmic (2 Hz) flexion and extension movements of the opposite (left) wrist. The potentials evoked by TMS in right FCR were potentiated during the phases of movement in which the left FCR was most strongly engaged. In contrast, CMEPs were unaffected by the movements of the opposite limb. These results suggest that there was systematic variation of the excitability of the motor cortex ipsilateral to the moving limb. H-reflexes and stretch reflexes recorded in right FCR were modulated in phase with the activation of left FCR. As the f-waves did not vary in corresponding fashion, it appears that the phasic modulation of the H-reflex was mediated by presynaptic inhibition of Ia afferents. The observation that both H-reflexes and f-waves were depressed markedly during movements of the opposite indicates that there may also have been postsynaptic inhibition or disfacilitation of the largest motor units. Our findings indicate that the patterned modulation of excitability in motor pathways that occurs during rhythmic movements of the opposite limb is mediated primarily by interhemispheric interactions between cortical motor areas. PMID:15331684

  5. Molecular bases of circadian rhythmicity in renal physiology and pathology

    PubMed Central

    Bonny, Olivier; Vinciguerra, Manlio; Gumz, Michelle L.; Mazzoccoli, Gianluigi

    2013-01-01

    The physiological processes that maintain body homeostasis oscillate during the day. Diurnal changes characterize kidney functions, comprising regulation of hydro-electrolytic and acid-base balance, reabsorption of small solutes and hormone production. Renal physiology is characterized by 24-h periodicity and contributes to circadian variability of blood pressure levels, related as well to nychthemeral changes of sodium sensitivity, physical activity, vascular tone, autonomic function and neurotransmitter release from sympathetic innervations. The circadian rhythmicity of body physiology is driven by central and peripheral biological clockworks and entrained by the geophysical light/dark cycle. Chronodisruption, defined as the mismatch between environmental–social cues and physiological–behavioral patterns, causes internal desynchronization of periodic functions, leading to pathophysiological mechanisms underlying degenerative, immune related, metabolic and neoplastic diseases. In this review we will address the genetic, molecular and anatomical elements that hardwire circadian rhythmicity in renal physiology and subtend disarray of time–dependent changes in renal pathology. PMID:23901050

  6. Volitional exaggeration of body size through fundamental and formant frequency modulation in humans

    PubMed Central

    Pisanski, Katarzyna; Mora, Emanuel C.; Pisanski, Annette; Reby, David; Sorokowski, Piotr; Frackowiak, Tomasz; Feinberg, David R.

    2016-01-01

    Several mammalian species scale their voice fundamental frequency (F0) and formant frequencies in competitive and mating contexts, reducing vocal tract and laryngeal allometry thereby exaggerating apparent body size. Although humans’ rare capacity to volitionally modulate these same frequencies is thought to subserve articulated speech, the potential function of voice frequency modulation in human nonverbal communication remains largely unexplored. Here, the voices of 167 men and women from Canada, Cuba, and Poland were recorded in a baseline condition and while volitionally imitating a physically small and large body size. Modulation of F0, formant spacing (∆F), and apparent vocal tract length (VTL) were measured using Praat. Our results indicate that men and women spontaneously and systemically increased VTL and decreased F0 to imitate a large body size, and reduced VTL and increased F0 to imitate small size. These voice modulations did not differ substantially across cultures, indicating potentially universal sound-size correspondences or anatomical and biomechanical constraints on voice modulation. In each culture, men generally modulated their voices (particularly formants) more than did women. This latter finding could help to explain sexual dimorphism in F0 and formants that is currently unaccounted for by sexual dimorphism in human vocal anatomy and body size. PMID:27687571

  7. Teaching Rhythmic Gymnastics: A Developmentally Appropriate Approach.

    ERIC Educational Resources Information Center

    Palmer, Heather C.

    This book is designed to guide teachers through the process of creating a developmentally appropriate rhythmic gymnastics program for children age 5-11. Rhythmic gymnastics programs develop fitness, inspire creativity, and allow all children to work at their own level. The book features 10 chapters in two parts. Part 1, "Getting Started on a…

  8. Effects of Gravity on Insect Circadian Rhythmicity

    NASA Technical Reports Server (NTRS)

    Hoban-Higgins, Tana M.

    2000-01-01

    Circadian rhythms - endogenous daily rhythmic fluctuations in virtually all characteristics of life - are generated and coordinated by the circadian timing system (CTS). The CTS is synchronized to the external 24-hour day by time cues such as the light/dark cycle. In an environment without time cues, the length of an animal's day is determined by the period of its internal pacemaker (tau) and the animal is said to be free-running. All life on earth evolved under the solar day; the CTS exists as an adaptation that allows organisms to anticipate and to prepare for rhythmic environmental fluctuations. All life on earth also evolved under the force of earth's gravitational environment. While it is therefore not surprising that changes in the lighting environment affect the CTS, it is surprising that changes in the gravitational environment would do so. However, recent data from one of our laboratories using the brn-3.1 knockout mouse revealed that this model, which lacks the sensory receptor hair cells within the neurovestibular system, does not respond to exposure to a hyperdynamic environment in the same fashion as normal mice. The brn-3.1 mice did not show the expected suppression of circadian rhythmicity shown by control mice exposed to 2G. Exposure to altered ambient force environments affects the amplitude, mean and timing of circadian rhythms in species from unicellular organisms to man. In addition, there is a circadian influence on the homeostatic response to acute 2G acceleration and pulses of 2G can act as a time cue, synchronizing the CTS. This is of significance because maintenance of internal and external temporal coordination is critical for normal physiological and psychological function. Typically, during adaptation to an increased gravitational environment (+G), an initial acute reaction is followed by adaptation and, eventually, a new steady state (14-16), which can take weeks to months to establish. Until the development of space stations, exposure

  9. Coordinated Rhythmic Motion by Uncoupled Neuronal Oscillators with Sensory Feedback

    NASA Astrophysics Data System (ADS)

    Iwasaki, Tetsuya

    This paper explores the potential of biological oscillators as a basic unit for feedback control to achieve rhythmic motion of locomotory systems. Among those properties of biological control systems that are useful for engineering applications, we focus on decentralized coordination, that is, the ability of uncoupled neuronal oscillators to coordinate rhythmic body movements to achieve locomotion with the aid of local sensory feedback. We will consider the reciprocal inhibition oscillator (RIO) as a candidate for the basic control unit, and show that uncoupled RIOs can achieve decentralized coordination of a prototype mechanical rectifier (PMR) that captures essential dynamics underlying animal locomotion by a simple arm-disk configuration. Optimality of the induced locomotion is studied in comparison with analytical results we derive for statically optimal PMR locomotion.

  10. Individual Differences in Rhythmic Cortical Entrainment Correlate with Predictive Behavior in Sensorimotor Synchronization

    PubMed Central

    Nozaradan, Sylvie; Peretz, Isabelle; Keller, Peter E.

    2016-01-01

    The current study aims at characterizing the mechanisms that allow humans to entrain the mind and body to incoming rhythmic sensory inputs in real time. We addressed this unresolved issue by examining the relationship between covert neural processes and overt behavior in the context of musical rhythm. We measured temporal prediction abilities, sensorimotor synchronization accuracy and neural entrainment to auditory rhythms as captured using an EEG frequency-tagging approach. Importantly, movement synchronization accuracy with a rhythmic beat could be explained by the amplitude of neural activity selectively locked with the beat period when listening to the rhythmic inputs. Furthermore, stronger endogenous neural entrainment at the beat frequency was associated with superior temporal prediction abilities. Together, these results reveal a direct link between cortical and behavioral measures of rhythmic entrainment, thus providing evidence that frequency-tagged brain activity has functional relevance for beat perception and synchronization. PMID:26847160

  11. Effects of rhythmic stimulus presentation on oscillatory brain activity: the physiology of cueing in Parkinson’s disease

    PubMed Central

    te Woerd, Erik S.; Oostenveld, Robert; Bloem, Bastiaan R.; de Lange, Floris P.; Praamstra, Peter

    2015-01-01

    The basal ganglia play an important role in beat perception and patients with Parkinson’s disease (PD) are impaired in perception of beat-based rhythms. Rhythmic cues are nonetheless beneficial in gait rehabilitation, raising the question how rhythm improves movement in PD. We addressed this question with magnetoencephalography recordings during a choice response task with rhythmic and non-rhythmic modes of stimulus presentation. Analyses focused on (i) entrainment of slow oscillations, (ii) the depth of beta power modulation, and (iii) whether a gain in modulation depth of beta power, due to rhythmicity, is of predictive or reactive nature. The results show weaker phase synchronisation of slow oscillations and a relative shift from predictive to reactive movement-related beta suppression in PD. Nonetheless, rhythmic stimulus presentation increased beta modulation depth to the same extent in patients and controls. Critically, this gain selectively increased the predictive and not reactive movement-related beta power suppression. Operation of a predictive mechanism, induced by rhythmic stimulation, was corroborated by a sensory gating effect in the sensorimotor cortex. The predictive mode of cue utilisation points to facilitation of basal ganglia-premotor interactions, contrasting with the popular view that rhythmic stimulation confers a special advantage in PD, based on recruitment of alternative pathways. PMID:26509117

  12. Illusory Changes in Body Size Modulate Body Satisfaction in a Way That Is Related to Non-Clinical Eating Disorder Psychopathology

    PubMed Central

    Preston, Catherine; Ehrsson, H. Henrik

    2014-01-01

    Historically, body size overestimation has been linked to abnormal levels of body dissatisfaction found in eating disorders. However, recently this relationship has been called into question. Indeed, despite a link between how we perceive and how we feel about our body seeming intuitive, until now lack of an experimental method to manipulate body size has meant that a causal link, even in healthy participants, has remained elusive. Recent developments in body perception research demonstrate that the perceptual experience of the body can be readily manipulated using multisensory illusions. The current study exploits such illusions to modulate perceived body size in an attempt to influence body satisfaction. Participants were presented with stereoscopic video images of slimmer and wider mannequin bodies viewed through head-mounted displays from first person perspective. Illusory ownership was induced by synchronously stroking the seen mannequin body with the unseen real body. Pre and post-illusion affective and perceptual measures captured changes in perceived body size and body satisfaction. Illusory ownership of a slimmer body resulted in participants perceiving their actual body as slimmer and giving higher ratings of body satisfaction demonstrating a direct link between perceptual and affective body representations. Change in body satisfaction following illusory ownership of a wider body, however, was related to degree of (non-clinical) eating disorder psychopathology, which can be linked to fluctuating body representations found in clinical samples. The results suggest that body perception is linked to body satisfaction and may be of importance for eating disorder symptomology. PMID:24465698

  13. Seeing the body produces limb-specific modulation of skin temperature.

    PubMed

    Sadibolova, Renata; Longo, Matthew R

    2014-01-01

    Vision of the body, even when non-informative about stimulation, affects somatosensory processing. We investigated whether seeing the body also modulates autonomic control in the periphery by measuring skin temperature while manipulating vision. Using a mirror box, the skin temperature was measured from left hand dorsum while participants: (i) had the illusion of seeing their left hand, (ii) had the illusion of seeing an object at the same location or (iii) looked directly at their contralateral right hand. Skin temperature of the left hand increased when participants had the illusion of directly seeing that hand but not in the other two view conditions. In experiment 2, participants viewed directly their left or right hand, or the box while we recorded both hand dorsum temperatures. Temperature increased in the viewed hand but not the contralateral hand. These results show that seeing the body produces limb-specific modulation of thermal regulation.

  14. Rhythmic engagement with music in infancy

    PubMed Central

    Zentner, Marcel; Eerola, Tuomas

    2010-01-01

    Humans have a unique ability to coordinate their motor movements to an external auditory stimulus, as in music-induced foot tapping or dancing. This behavior currently engages the attention of scholars across a number of disciplines. However, very little is known about its earliest manifestations. The aim of the current research was to examine whether preverbal infants engage in rhythmic behavior to music. To this end, we carried out two experiments in which we tested 120 infants (aged 5–24 months). Infants were exposed to various excerpts of musical and rhythmic stimuli, including isochronous drumbeats. Control stimuli consisted of adult- and infant-directed speech. Infants’ rhythmic movements were assessed by multiple methods involving manual coding from video excerpts and innovative 3D motion-capture technology. The results show that (i) infants engage in significantly more rhythmic movement to music and other rhythmically regular sounds than to speech; (ii) infants exhibit tempo flexibility to some extent (e.g., faster auditory tempo is associated with faster movement tempo); and (iii) the degree of rhythmic coordination with music is positively related to displays of positive affect. The findings are suggestive of a predisposition for rhythmic movement in response to music and other metrically regular sounds. PMID:20231438

  15. Rhythmic engagement with music in infancy.

    PubMed

    Zentner, Marcel; Eerola, Tuomas

    2010-03-30

    Humans have a unique ability to coordinate their motor movements to an external auditory stimulus, as in music-induced foot tapping or dancing. This behavior currently engages the attention of scholars across a number of disciplines. However, very little is known about its earliest manifestations. The aim of the current research was to examine whether preverbal infants engage in rhythmic behavior to music. To this end, we carried out two experiments in which we tested 120 infants (aged 5-24 months). Infants were exposed to various excerpts of musical and rhythmic stimuli, including isochronous drumbeats. Control stimuli consisted of adult- and infant-directed speech. Infants' rhythmic movements were assessed by multiple methods involving manual coding from video excerpts and innovative 3D motion-capture technology. The results show that (i) infants engage in significantly more rhythmic movement to music and other rhythmically regular sounds than to speech; (ii) infants exhibit tempo flexibility to some extent (e.g., faster auditory tempo is associated with faster movement tempo); and (iii) the degree of rhythmic coordination with music is positively related to displays of positive affect. The findings are suggestive of a predisposition for rhythmic movement in response to music and other metrically regular sounds.

  16. Spectral mixing of rhythmic neuronal signals in sensory cortex

    PubMed Central

    Ahrens, Kurt F.; Levine, Herbert; Suhl, Harry; Kleinfeld, David

    2002-01-01

    The ability to compute the difference between two frequencies depends on a nonlinear operation that mixes two periodic signals. Behavioral and psychophysical evidence suggest that such mixing is likely to occur in the mammalian nervous system as a means to compare two rhythmic sensory signals, such as occurs in human audition, and as a means to lock an intrinsic rhythm to a sensory input. However, a neurological substrate for mixing has not been identified. Here we address the issue of nonlinear mixing of neuronal activity in the vibrissa primary sensory cortex of rat, a region that receives intrinsic as well as sensory-driven rhythmic input during natural whisking. In our preparation, the intrinsic signal originates from cortical oscillations that were induced by anesthetics, and the extrinsic input is introduced by periodic stimulation of vibrissae. We observed that the local extracellular current in vibrissa primary sensory cortex contained oscillatory components at the sum and difference of the intrinsic and extrinsic frequencies. In complementary experiments, we observed that the simultaneous stimulation of contralateral and ipsilateral vibrissae at different frequencies also led to current flow at the sum and difference frequencies. We show theoretically that the relative amplitudes of the observed mixture terms can be accounted for by a threshold nonlinearity in the input–output relation of the underlying neurons. In general, our results provide a neurological substrate for the modulation and demodulation of rhythmic neuronal signals for sensory coding and feedback stabilization of motor output. PMID:12403828

  17. Artistic versus rhythmic gymnastics: effects on bone and muscle mass in young girls.

    PubMed

    Vicente-Rodriguez, G; Dorado, C; Ara, I; Perez-Gomez, J; Olmedillas, H; Delgado-Guerra, S; Calbet, J A L

    2007-05-01

    We compared 35 prepubertal girls, 9 artistic gymnasts and 13 rhythmic gymnasts with 13 nonphysically active controls to study the effect of gymnastics on bone and muscle mass. Lean mass, bone mineral content and areal density were measured by dual energy X-ray absorptiometry, and physical fitness was also assessed. The artistic gymnasts showed a delay in pubertal development compared to the other groups (p<0.05). The artistic gymnasts had a 16 and 17 % higher aerobic power and anaerobic capacity, while the rhythmic group had a 14 % higher anaerobic capacity than the controls, respectively (all p<0.05). The artistic gymnasts had higher lean mass (p<0.05) in the whole body and the extremities than both the rhythmic gymnasts and the controls. Body fat mass was 87.5 and 61.5 % higher in the controls than in the artistic and the rhythmic gymnasts (p<0.05). The upper extremity BMD was higher (p<0.05) in the artistic group compared to the other groups. Lean mass strongly correlated with bone mineral content (r=0.84, p<0.001), and multiple regression analysis showed that total lean mass explained 64 % of the variability in whole body bone mineral content, but only 20 % in whole body bone mineral density. Therefore, recreational artistic gymnastic participation is associated with delayed pubertal development, enhanced physical fitness, muscle mass, and bone density in prepubertal girls, eliciting a higher osteogenic stimulus than rhythmic gymnastic.

  18. Circadian regulation of pineal gland rhythmicity.

    PubMed

    Borjigin, Jimo; Zhang, L Samantha; Calinescu, Anda-Alexandra

    2012-02-05

    The pineal gland is a neuroendocrine organ of the brain. Its main task is to synthesize and secrete melatonin, a nocturnal hormone with diverse physiological functions. This review will focus on the central and pineal mechanisms in generation of mammalian pineal rhythmicity including melatonin production. In particular, this review covers the following topics: (1) local control of serotonin and melatonin rhythms; (2) neurotransmitters involved in central control of melatonin; (3) plasticity of the neural circuit controlling melatonin production; (4) role of clock genes in melatonin formation; (5) phase control of pineal rhythmicity; (6) impact of light at night on pineal rhythms; and (7) physiological function of the pineal rhythmicity.

  19. Modulation of the gut microbiota with antibiotic treatment suppresses whole body urea production in neonatal pigs.

    PubMed

    Puiman, Patrycja; Stoll, Barbara; Mølbak, Lars; de Bruijn, Adrianus; Schierbeek, Henk; Boye, Mette; Boehm, Günther; Renes, Ingrid; van Goudoever, Johannes; Burrin, Douglas

    2013-02-01

    We examined whether changes in the gut microbiota induced by clinically relevant interventions would impact the bioavailability of dietary amino acids in neonates. We tested the hypothesis that modulation of the gut microbiota in neonatal pigs receiving no treatment (control), intravenously administered antibiotics, or probiotics affects whole body nitrogen and amino acid turnover. We quantified whole body urea kinetics, threonine fluxes, and threonine disposal into protein, oxidation, and tissue protein synthesis with stable isotope techniques. Compared with controls, antibiotics reduced the number and diversity of bacterial species in the distal small intestine (SI) and colon. Antibiotics decreased plasma urea concentrations via decreased urea synthesis. Antibiotics elevated threonine plasma concentrations and turnover, as well as whole body protein synthesis and proteolysis. Antibiotics decreased protein synthesis rate in the proximal SI and liver but did not affect the distal SI, colon, or muscle. Probiotics induced a bifidogenic microbiota and decreased plasma urea concentrations but did not affect whole body threonine or protein metabolism. Probiotics decreased protein synthesis in the proximal SI but not in other tissues. In conclusion, modulation of the gut microbiota by antibiotics and probiotics reduced hepatic ureagenesis and intestinal protein synthesis, but neither altered whole body net threonine balance. These findings suggest that changes in amino acid and nitrogen metabolism resulting from antibiotic- or probiotic-induced shifts in the microbiota are localized to the gut and liver and have limited impact on whole body growth and anabolism in neonatal piglets.

  20. Size matters: plasticity in metabolic scaling shows body-size may modulate responses to climate change

    PubMed Central

    Carey, Nicholas; Sigwart, Julia D.

    2014-01-01

    Variability in metabolic scaling in animals, the relationship between metabolic rate (R) and body mass (M), has been a source of debate and controversy for decades. R is proportional to Mb, the precise value of b much debated, but historically considered equal in all organisms. Recent metabolic theory, however, predicts b to vary among species with ecology and metabolic level, and may also vary within species under different abiotic conditions. Under climate change, most species will experience increased temperatures, and marine organisms will experience the additional stressor of decreased seawater pH (‘ocean acidification’). Responses to these environmental changes are modulated by myriad species-specific factors. Body-size is a fundamental biological parameter, but its modulating role is relatively unexplored. Here, we show that changes to metabolic scaling reveal asymmetric responses to stressors across body-size ranges; b is systematically decreased under increasing temperature in three grazing molluscs, indicating smaller individuals were more responsive to warming. Larger individuals were, however, more responsive to reduced seawater pH in low temperatures. These alterations to the allometry of metabolism highlight abiotic control of metabolic scaling, and indicate that responses to climate warming and ocean acidification may be modulated by body-size. PMID:25122741

  1. Size matters: plasticity in metabolic scaling shows body-size may modulate responses to climate change.

    PubMed

    Carey, Nicholas; Sigwart, Julia D

    2014-08-01

    Variability in metabolic scaling in animals, the relationship between metabolic rate ( R: ) and body mass ( M: ), has been a source of debate and controversy for decades. R: is proportional to MB: , the precise value of B: much debated, but historically considered equal in all organisms. Recent metabolic theory, however, predicts B: to vary among species with ecology and metabolic level, and may also vary within species under different abiotic conditions. Under climate change, most species will experience increased temperatures, and marine organisms will experience the additional stressor of decreased seawater pH ('ocean acidification'). Responses to these environmental changes are modulated by myriad species-specific factors. Body-size is a fundamental biological parameter, but its modulating role is relatively unexplored. Here, we show that changes to metabolic scaling reveal asymmetric responses to stressors across body-size ranges; B: is systematically decreased under increasing temperature in three grazing molluscs, indicating smaller individuals were more responsive to warming. Larger individuals were, however, more responsive to reduced seawater pH in low temperatures. These alterations to the allometry of metabolism highlight abiotic control of metabolic scaling, and indicate that responses to climate warming and ocean acidification may be modulated by body-size.

  2. Predictors of attainment in rhythmic sportive gymnastics.

    PubMed

    Hume, P A; Hopkins, W G; Robinson, D M; Robinson, S M; Hollings, S C

    1993-12-01

    Correlates of attainment in rhythmic sportive gymnastics (RSG) were investigated in a cross-sectional study of 106 female gymnasts aged 7-27 years. Physical attributes were obtained by anthropometry and from tests of flexibility, leg power, maximum oxygen uptake and visuo-motor proficiency. Training and psychological measures were derived from self-administered questionnaires that included the Leadership Scale for Sport, Psychological Skills Inventory for Sport, General Health Questionnaire, Sport Competition Anxiety Test, and several questions on sport motivation and enjoyment. Attainment was expressed as competition grade level and mean performance score in 4 competitions. The best correlates of attainment were cumulative and current training time (r = 0.84-0.53). Age, lean body mass and composite measures of flexibility, leg power and visuo-motor proficiency were also significant correlates of attainment (r = 0.69-0.29), as were coach democratic and coach social behaviours (r = 0.41-0.28). The significant positive psychometric correlates of attainment were mental preparation, motivation by creativity, and several dimensions of enjoyment (r = 0.35-0.26); significant negative correlates were recent anxiety-depression and enjoyment of training (r = -0.34-(-)0.32). No previous study has identified the relative contributions of such a comprehensive range of physical, psychological and training measures to performance of a sport.

  3. Impact of nutrients on circadian rhythmicity.

    PubMed

    Oosterman, Johanneke E; Kalsbeek, Andries; la Fleur, Susanne E; Belsham, Denise D

    2015-03-01

    The suprachiasmatic nucleus (SCN) in the mammalian hypothalamus functions as an endogenous pacemaker that generates and maintains circadian rhythms throughout the body. Next to this central clock, peripheral oscillators exist in almost all mammalian tissues. Whereas the SCN is mainly entrained to the environment by light, peripheral clocks are entrained by various factors, of which feeding/fasting is the most important. Desynchronization between the central and peripheral clocks by, for instance, altered timing of food intake can lead to uncoupling of peripheral clocks from the central pacemaker and is, in humans, related to the development of metabolic disorders, including obesity and Type 2 diabetes. Diets high in fat or sugar have been shown to alter circadian clock function. This review discusses the recent findings concerning the influence of nutrients, in particular fatty acids and glucose, on behavioral and molecular circadian rhythms and will summarize critical studies describing putative mechanisms by which these nutrients are able to alter normal circadian rhythmicity, in the SCN, in non-SCN brain areas, as well as in peripheral organs. As the effects of fat and sugar on the clock could be through alterations in energy status, the role of specific nutrient sensors will be outlined, as well as the molecular studies linking these components to metabolism. Understanding the impact of specific macronutrients on the circadian clock will allow for guidance toward the composition and timing of meals optimal for physiological health, as well as putative therapeutic targets to regulate the molecular clock.

  4. Impact of nutrients on circadian rhythmicity

    PubMed Central

    Oosterman, Johanneke E.; Kalsbeek, Andries; la Fleur, Susanne E.

    2014-01-01

    The suprachiasmatic nucleus (SCN) in the mammalian hypothalamus functions as an endogenous pacemaker that generates and maintains circadian rhythms throughout the body. Next to this central clock, peripheral oscillators exist in almost all mammalian tissues. Whereas the SCN is mainly entrained to the environment by light, peripheral clocks are entrained by various factors, of which feeding/fasting is the most important. Desynchronization between the central and peripheral clocks by, for instance, altered timing of food intake can lead to uncoupling of peripheral clocks from the central pacemaker and is, in humans, related to the development of metabolic disorders, including obesity and Type 2 diabetes. Diets high in fat or sugar have been shown to alter circadian clock function. This review discusses the recent findings concerning the influence of nutrients, in particular fatty acids and glucose, on behavioral and molecular circadian rhythms and will summarize critical studies describing putative mechanisms by which these nutrients are able to alter normal circadian rhythmicity, in the SCN, in non-SCN brain areas, as well as in peripheral organs. As the effects of fat and sugar on the clock could be through alterations in energy status, the role of specific nutrient sensors will be outlined, as well as the molecular studies linking these components to metabolism. Understanding the impact of specific macronutrients on the circadian clock will allow for guidance toward the composition and timing of meals optimal for physiological health, as well as putative therapeutic targets to regulate the molecular clock. PMID:25519730

  5. Rhythmic Gymnastics: A Challenge with Balls and Ropes.

    ERIC Educational Resources Information Center

    Bennett, John P.

    Rhythmic gymnastics is an outgrowth of rhythmic and dance gymnastics and promotes good posture, strength, flexibility, balance, and coordination, along with appreciation of music and movement together. The current status of rhythmic gymnastics and its historical development are briefly discussed. Descriptions are given of rhythmic gymnastic…

  6. Neurotransmission in the carotid body: transmitters and modulators between glomus cells and petrosal ganglion nerve terminals.

    PubMed

    Iturriaga, Rodrigo; Alcayaga, Julio

    2004-12-01

    The carotid body (CB) is the main arterial chemoreceptor. The most accepted model of arterial chemoreception postulates that carotid body glomus (type I) cells are the primary receptors, which are synaptically connected to the nerve terminals of petrosal ganglion (PG) neurons. In response to natural stimuli, glomus cells are expected to release one (or more) transmitter(s) which, acting on the peripheral nerve terminals of processes from chemosensory petrosal neurons, increases the sensory discharge. Among several molecules present in glomus cells, acetylcholine and adenosine nucleotides and dopamine are considered as excitatory transmitter candidates. In this review, we will examine recent evidence supporting the notion that acetylcholine and adenosine 5'-triphosphate are the main excitatory transmitters in the cat and rat carotid bodies. On the other hand, dopamine may act as a modulator of the chemoreception process in the cat, but as an excitatory transmitter in the rabbit carotid body.

  7. Body Fat and Physical Activity Modulate the Association Between Sarcopenia and Osteoporosis in Elderly Korean Women

    PubMed Central

    Lee, Inhwan; Cho, Jinkyung; Jin, Youngyun; Ha, Changduk; Kim, Taehee; Kang, Hyunsik

    2016-01-01

    This study examined whether modifiable lifestyle factors, such as body fatness and physical activity, modulate the association between sarcopenia and osteoporosis. In a cross-sectional design, 269 postmenopausal women, aged 65 years and older, underwent dual-energy X-ray absorptiometry (DEXA) scans to measure their body fat percentage, total fat mass, total fat-free mass, appendicular lean mass, bone mineral density (BMD) and bone mineral content. The participants wore a uniaxial accelerometer for seven consecutive days to quantify daily physical activity. The collected data were analyzed using descriptive statistics, Pearson correlation, and a binary logistic regression. Pearson correlation analyses showed that total neck/femur BMD was positively associated with weight-adjusted appendicular skeletal muscle mass (ASM) and objectively-measured physical activities. ASM was positively associated with body fatness. Binary logistic regression analyses showed that the odds ratio (OR) of sarcopenia for osteopenia and/or osteoporosis was substantially attenuated but remained marginally significant when adjusted for age and postmenopausal period (OR = 2.370 and p = 0.050). However, the OR was no longer significant when additionally adjusted for body fatness (OR = 2.218 and p = 0.117) and physical activity (OR = 1.240 and p = 0.448). The findings of the study showed that, in this sample of elderly Korean women, modifiable lifestyle risk factors such as body fatness and physical inactivity played an important role in determining the association between sarcopenia and osteopenia/osteoporosis. Key points Osteoporosis and sarcopenia are major health conditions responsible for an increased risk of bone fractures and reduced functional capacity, respectively, in older adults. We investigated whether lifestyle-related risk factors modulate the association between sarcopenia and osteoporosis in older Korean adults. The current findings of the study suggest that physical activity and

  8. Thyroid Hormone and Seasonal Rhythmicity

    PubMed Central

    Dardente, Hugues; Hazlerigg, David G.; Ebling, Francis J. P.

    2014-01-01

    Living organisms show seasonality in a wide array of functions such as reproduction, fattening, hibernation, and migration. At temperate latitudes, changes in photoperiod maintain the alignment of annual rhythms with predictable changes in the environment. The appropriate physiological response to changing photoperiod in mammals requires retinal detection of light and pineal secretion of melatonin, but extraretinal detection of light occurs in birds. A common mechanism across all vertebrates is that these photoperiod-regulated systems alter hypothalamic thyroid hormone (TH) conversion. Here, we review the evidence that a circadian clock within the pars tuberalis of the adenohypophysis links photoperiod decoding to local changes of TH signaling within the medio-basal hypothalamus (MBH) through a conserved thyrotropin/deiodinase axis. We also focus on recent findings which indicate that, beyond the photoperiodic control of its conversion, TH might also be involved in longer-term timing processes of seasonal programs. Finally, we examine the potential implication of kisspeptin and RFRP3, two RF-amide peptides expressed within the MBH, in seasonal rhythmicity. PMID:24616714

  9. Does Human Milk Modulate Body Composition in Late Preterm Infants at Term-Corrected Age?

    PubMed Central

    Giannì, Maria Lorella; Consonni, Dario; Liotto, Nadia; Roggero, Paola; Morlacchi, Laura; Piemontese, Pasqua; Menis, Camilla; Mosca, Fabio

    2016-01-01

    (1) Background: Late preterm infants account for the majority of preterm births and are at risk of altered body composition. Because body composition modulates later health outcomes and human milk is recommended as the normal method for infant feeding, we sought to investigate whether human milk feeding in early life can modulate body composition development in late preterm infants; (2) Methods: Neonatal, anthropometric and feeding data of 284 late preterm infants were collected. Body composition was evaluated at term-corrected age by air displacement plethysmography. The effect of human milk feeding on fat-free mass and fat mass content was evaluated using multiple linear regression analysis; (3) Results: Human milk was fed to 68% of the infants. According to multiple regression analysis, being fed any human milk at discharge and at  term-corrected and being fed exclusively human milk at term-corrected age were positively associated with fat-free mass content(β = −47.9, 95% confidence interval (CI) = −95.7; −0.18; p = 0.049; β = −89.6, 95% CI = −131.5; −47.7; p < 0.0001; β = −104.1, 95% CI = −151.4; −56.7, p < 0.0001); (4) Conclusion: Human milk feeding appears to be associated with fat-free mass deposition in late preterm infants. Healthcare professionals should direct efforts toward promoting and supporting breastfeeding in these vulnerable infants. PMID:27782098

  10. Does Human Milk Modulate Body Composition in Late Preterm Infants at Term-Corrected Age?

    PubMed

    Giannì, Maria Lorella; Consonni, Dario; Liotto, Nadia; Roggero, Paola; Morlacchi, Laura; Piemontese, Pasqua; Menis, Camilla; Mosca, Fabio

    2016-10-23

    (1) Background: Late preterm infants account for the majority of preterm births and are at risk of altered body composition. Because body composition modulates later health outcomes and human milk is recommended as the normal method for infant feeding, we sought to investigate whether human milk feeding in early life can modulate body composition development in late preterm infants; (2) Methods: Neonatal, anthropometric and feeding data of 284 late preterm infants were collected. Body composition was evaluated at term-corrected age by air displacement plethysmography. The effect of human milk feeding on fat-free mass and fat mass content was evaluated using multiple linear regression analysis; (3) Results: Human milk was fed to 68% of the infants. According to multiple regression analysis, being fed any human milk at discharge and at  term-corrected and being fed exclusively human milk at term-corrected age were positively associated with fat-free mass content(β = -47.9, 95% confidence interval (CI) = -95.7; -0.18; p = 0.049; β = -89.6, 95% CI = -131.5; -47.7; p < 0.0001; β = -104.1, 95% CI = -151.4; -56.7, p < 0.0001); (4) Conclusion: Human milk feeding appears to be associated with fat-free mass deposition in late preterm infants. Healthcare professionals should direct efforts toward promoting and supporting breastfeeding in these vulnerable infants.

  11. Visuospatial viewpoint manipulation during full-body illusion modulates subjective first-person perspective.

    PubMed

    Pfeiffer, Christian; Schmutz, Valentin; Blanke, Olaf

    2014-12-01

    Self-consciousness is based on multisensory signals from the body. In full-body illusion (FBI) experiments, multisensory conflict was used to induce changes in three key aspects of bodily self-consciousness (BSC): self-identification (which body 'I' identify with), self-location (where 'I' am located), and first-person perspective (from where 'I' experience the world; 1PP). Here, we adapted a previous FBI protocol in which visuotactile stroking was administered by a robotic device (tactile stroking) and simultaneously rendered on the back of a virtual body (visual stroking) that participants viewed on a head-mounted display as if filmed from a posterior viewpoint of a camera. We compared the effects of two different visuospatial viewpoints on the FBI and thereby on these key aspects of BSC. During control manipulations, participants saw a no-body object instead of a virtual body (first experiment) or received asynchronous versus synchronous visuotactile stroking (second experiment). Results showed that within-subjects visuospatial viewpoint manipulations affected the subjective 1PP ratings if a virtual body was seen but had no effect for viewing a non-body object. However, visuospatial viewpoint had no effect on self-identification, but depended on the viewed object and visuotactile synchrony. Self-location depended on visuospatial viewpoint (first experiment) and visuotactile synchrony (second experiment). Our results show that the visuospatial viewpoint from which the virtual body is seen during FBIs modulates the subjective 1PP and that such viewpoint manipulations contribute to spatial aspects of BSC. We compare the present data with recent data revealing vestibular contributions to the subjective 1PP and discuss the multisensory nature of BSC and the subjective 1PP.

  12. Task-dependent modulation of medial geniculate body is behaviorally relevant for speech recognition.

    PubMed

    von Kriegstein, Katharina; Patterson, Roy D; Griffiths, T D

    2008-12-09

    Recent work has shown that responses in first-order sensory thalamic nuclei are modulated by cortical areas. However, the functional role of such corticothalamic modulation and its relevance for human perception is still unclear. Here, we show in two functional magnetic resonance imaging (fMRI) studies that the neuronal response in the first-order auditory thalamus, the medial geniculate body (MGB), is increased when rapidly varying spectrotemporal features of speech sounds are processed, as compared to processing slowly varying spectrotemporal features of the same sounds. The strength of this task-dependent modulation is positively correlated with the speech recognition scores of individual subjects. These results show that task-dependent modulation of the MGB serves the processing of specific features of speech sounds and is behaviorally relevant for speech recognition. Our findings suggest that the first-order auditory thalamus is not simply a nonspecific gatekeeper controlled by attention. Together with studies in nonhuman mammals, our findings imply a mechanism in which the first-order auditory thalamus, possibly by corticothalamic modulation, reacts adaptively to features of sensory input.

  13. The processing of body expressions during emotional scenes: the modulation role of attachment styles

    PubMed Central

    Ma, Yuanxiao; Chen, Xu; Ran, Guangming; Ma, Haijing; Zhang, Xing; Liu, Guangzeng

    2017-01-01

    There is broad evidence indicating that contextual information influence the processing of emotional stimuli. However, attachment theory suggests that attachment styles contribute to the ways in which people perceive emotional events. To shed light on whether the processing of body expressions during different emotional scenes is modulated by attachment styles, attachment-related electrophysiological differences were measured using event-related potentials. For avoidantly attached group, our results suggested that larger N170 amplitudes were educed by neutral bodies than angry bodies, which was found only in neutral scene. Moreover, significant differences were found in P300 amplitudes in response to angry bodies compared with neutral ones only during angry scene. However, securely and anxiously attached individuals were associated with larger P300 amplitudes in response to angry bodies versus neutral ones in both emotional scenes. The current study highlights the characteristics of cognitive processing of attachment styles on body expressions during different emotional scenes, with the variation of N170 and P300 amplitude in different emotional scenes as the best example. PMID:28303949

  14. Skeletal muscle PGC-1α modulates systemic ketone body homeostasis and ameliorates diabetic hyperketonemia in mice

    PubMed Central

    Svensson, Kristoffer; Albert, Verena; Cardel, Bettina; Salatino, Silvia; Handschin, Christoph

    2016-01-01

    Ketone bodies are crucial energy substrates during states of low carbohydrate availability. However, an aberrant regulation of ketone body homeostasis can lead to complications such as diabetic ketoacidosis. Exercise and diabetes affect systemic ketone body homeostasis, but the regulation of ketone body metabolism is still enigmatic. Using mice with either a knockout or overexpression of the peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) in skeletal muscle, we show that PGC-1α regulates ketolytic gene transcription in muscle. Furthermore, ketone body homeostasis of these mice was investigated during fasting, exercise, ketogenic diet feeding and after streptozotocin injection. In response to these ketogenic stimuli, we show that modulation of PGC-1α levels in muscle affects systemic ketone body homeostasis. Moreover, our data demonstrate that skeletal muscle PGC-1α is necessary for the enhanced ketolytic capacity in response to exercise training and overexpression of PGC-1α in muscle enhances systemic ketolytic capacity and is sufficient to ameliorate diabetic hyperketonemia in mice. Using cultured myotubes, we also show that the transcription factor estrogen related receptor α (ERRα) is a partner of PGC-1α in the regulation of ketolytic gene transcription. Collectively, these results demonstrate a central role of skeletal muscle PGC-1α in the transcriptional regulation of systemic ketolytic capacity. PMID:26849960

  15. Motor control of rhythmic dance from a dynamical systems perspective: a review.

    PubMed

    Miura, Akito; Fujii, Shinya; Yamamoto, Yuji; Kudo, Kazutoshi

    2015-03-01

    While dancers and dance educators express great interest in motor control as it relates to rhythmic dance, the subject remains largely uninvestigated. In order to advance our understanding of motor control, a theoretical framework called the dynamical systems approach (DSA) has been used. The DSA was originally developed to describe mathematically the principle of synchronization patterns in nature and their change over time. In recent decades, researchers studying human motor control have attempted to describe the synchronization of rhythmic movement using a DSA. More recently, this approach has been applied specifically to rhythmic dance movements. A series of studies that used the DSA revealed that when people synchronize rhythmic movement of a body part 1. with a different body part, 2. with other people's movement, or 3. with an auditory beat with some phase differences, unintentional and autonomous entrainment to a specific synchronization pattern occurs. However, through practice dancers are able to overcome such entrainment and dance freely. These findings provide practical suggestions for effective ways of training in dance education. The DSA can potentially be an effective tool for furthering our understanding of the motor control utilized in rhythmic dance.

  16. Modulation of anticipatory postural activity for multiple conditions of a whole-body pointing task.

    PubMed

    Tolambiya, A; Chiovetto, E; Pozzo, T; Thomas, E

    2012-05-17

    This is a study on associated postural activities during the anticipatory segments of a multijoint movement. Several previous studies have shown that they are task dependant. The previous studies, however, have mostly been limited in demonstrating the presence of modulation for one task condition, that is, one aspect such as the distance of the target or the direction of reaching. Real-life activities like whole-body pointing, however, can vary in several ways. How specific is the adaptation of the postural activities for the diverse possibilities of a whole-body pointing task? We used a classification paradigm to answer this question. We examined the anticipatory postural electromyograms for four different types of whole-body pointing tasks. The presence of task-dependent modulations in these signals was probed by performing four-way classification tests using a support vector machine (SVM). The SVM was able to achieve significantly higher than chance performance in correctly predicting the movements at hand (Chance performance 25%). Using only anticipatory postural muscle activity, the correct movement at hand was predicted with a mean rate of 62%. Because this is 37% above chance performance, it suggests the presence of postural modulation for diverse conditions. The anticipatory activities consisted of both activations and deactivations. Movement prediction with the use of the activating muscles was significantly better than that obtained with the deactivating muscles. This suggests that more specific modulations for the movement at hand take place through activation, whereas the deactivation is more general. The study introduces a new method for investigating adaptations in motor control. It also sheds new light on the quantity and quality of information available in the feedforward segments of a voluntary multijoint motor activity.

  17. Modulation of adipose tissue lipolysis and body weight by high-density lipoproteins in mice

    PubMed Central

    Wei, H; Averill, M M; McMillen, T S; Dastvan, F; Mitra, P; Subramanian, S; Tang, C; Chait, A; LeBoeuf, R C

    2014-01-01

    Background: Obesity is associated with reduced levels of circulating high-density lipoproteins (HDLs) and its major protein, apolipoprotein (apo) A-I. As a result of the role of HDL and apoA-I in cellular lipid transport, low HDL and apoA-I may contribute directly to establishing or maintaining the obese condition. Methods: To test this, male C57BL/6 wild-type (WT), apoA-I deficient (apoA-I−/−) and apoA-I transgenic (apoA-Itg/tg) mice were fed obesogenic diets (ODs) and monitored for several clinical parameters. We also performed cell culture studies. Results: ApoA-I−/− mice gained significantly more body weight and body fat than WT mice over 20 weeks despite their reduced food intake. During a caloric restriction regime imposed on OD-fed mice, apoA-I deficiency significantly inhibited the loss of body fat as compared with WT mice. Reduced body fat loss with caloric restriction in apoA-I−/− mice was associated with blunted stimulated adipose tissue lipolysis as verified by decreased levels of phosphorylated hormone-sensitive lipase (p-HSL) and lipolytic enzyme mRNA. In contrast to apoA-I−/− mice, apoA-Itg/tg mice gained relatively less weight than WT mice, consistent with other reports. ApoA-Itg/tg mice showed increased adipose tissue lipolysis, verified by increased levels of p-HSL and lipolytic enzyme mRNA. In cell culture studies, HDL and apoA-I specifically increased catecholamine-induced lipolysis possibly through modulating the adipocyte plasma membrane cholesterol content. Conclusions: Thus, apoA-I and HDL contribute to modulating body fat content by controlling the extent of lipolysis. ApoA-I and HDL are key components of lipid metabolism in adipose tissue and constitute new therapeutic targets in obesity. PMID:24567123

  18. When your arm becomes mine: pathological embodiment of alien limbs using tools modulates own body representation.

    PubMed

    Garbarini, Francesca; Fossataro, Carlotta; Berti, Anna; Gindri, Patrizia; Romano, Daniele; Pia, Lorenzo; della Gatta, Francesco; Maravita, Angelo; Neppi-Modona, Marco

    2015-04-01

    Previous evidence has shown that active tool-use can reshape one's own body schema, extend peripersonal space and modulate the representation of related body parts. Here we investigate the effect of tool-use training on length representation of the contralesional forearm in brain-damaged hemiplegic patients who manifested a pathological embodiment of other people body parts. Four patients and 20 aged-matched healthy-controls were asked to estimate the mid-point of their contralesional forearm before and after 15 min of tool-use training (i.e. retrieving targets with a garbage plier). In the case of patients, training was always performed by the examiner's (alien) arm acting in two different positions, aligned (where the pathological embodiment occurs; E+ condition) or misaligned (where the pathological embodiment does not occur; E- condition) relative to the patients' shoulder. Healthy controls performed tool-use training either with their own arm (action condition) or observing the examiner's arm performing the task (observation condition), handling (observation with-tool condition) or not (observation without-tool condition) a similar tool. Crucially, in the E+ condition, when patients were convinced to perform the tool-use training with their own paralyzed arm, a significant overestimation effect was found (as in the Action condition with normal subjects): patients mislocated their forearm midpoint more proximally to the hand in the post- than in the pre-training phase. Conversely, in the E- condition, they did not show any overestimation effect, similarly to healthy subjects in the observation condition (neither in the with-tool nor in the without-tool condition significant overestimation effects were found). These findings show the existence of a tight link between spatial, motor and bodily representations and provide strong evidence that a pathological sense of body ownership can extend to intentional motor processes and modulate the sensory map of action

  19. An invisible touch: Body-related multisensory conflicts modulate visual consciousness.

    PubMed

    Salomon, Roy; Galli, Giulia; Łukowska, Marta; Faivre, Nathan; Ruiz, Javier Bello; Blanke, Olaf

    2016-07-29

    The majority of scientific studies on consciousness have focused on vision, exploring the cognitive and neural mechanisms of conscious access to visual stimuli. In parallel, studies on bodily consciousness have revealed that bodily (i.e. tactile, proprioceptive, visceral, vestibular) signals are the basis for the sense of self. However, the role of bodily signals in the formation of visual consciousness is not well understood. Here we investigated how body-related visuo-tactile stimulation modulates conscious access to visual stimuli. We used a robotic platform to apply controlled tactile stimulation to the participants' back while they viewed a dot moving either in synchrony or asynchrony with the touch on their back. Critically, the dot was rendered invisible through continuous flash suppression. Manipulating the visual context by presenting the dot moving on either a body form, or a non-bodily object we show that: (i) conflict induced by synchronous visuo-tactile stimulation in a body context is associated with a delayed conscious access compared to asynchronous visuo-tactile stimulation, (ii) this effect occurs only in the context of a visual body form, and (iii) is not due to detection or response biases. The results indicate that body-related visuo-tactile conflicts impact visual consciousness by facilitating access of non-conflicting visual information to awareness, and that these are sensitive to the visual context in which they are presented, highlighting the interplay between bodily signals and visual experience.

  20. Rhythmic and dysrhythmic thalamocortical dynamics: GABA systems and the edge effect.

    PubMed

    Llinás, Rodolfo; Urbano, Francisco J; Leznik, Elena; Ramírez, Rey R; van Marle, Hein J F

    2005-06-01

    Brain function is fundamentally related in the most general sense to the richness of thalamocortical interconnectivity, and in particular to the rhythmic oscillatory properties of thalamocortical loops. Such rhythmicity is involved in the genesis of cognition, in the sleep-wake cycle, and in several neurological and psychiatric disorders. The role of GABA-mediated transmission in regulating these functional states is addressed here. At the cortical level, inhibition determines the spread of cortical activation by sculpting the precise activity patterns that underlie the details of cognition and motor control. At the thalamic level, GABA-mediated inhibition modulates and resets distribution of the ongoing thalamocortical rhythmic oscillations that bind multisensory inputs into a single cognitive experience and regulate arousal levels.

  1. Systems Level Regulation of Rhythmic Growth Rate and Biomass Accumulation in Grasses

    SciTech Connect

    Kay, Steve A.

    2013-05-02

    Several breakthroughs have been recently made in our understanding of plant growth and biomass accumulation. It was found that plant growth is rhythmically controlled throughout the day by the circadian clock through a complex interplay of light and phytohormone signaling pathways. While plants such as the C4 energy crop sorghum (Sorghum bicolor (L.) Moench) and possibly the C3 grass (Brachypodium distachyon) also exhibit daily rhythms in growth rate, the molecular details of its regulation remain to be explored. A better understanding of diurnally regulated growth behavior in grasses may lead to species-specific mechanisms highly relevant to future strategies to optimize energy crop biomass yield. Here we propose to devise a systems approach to identify, in parallel, regulatory hubs associated with rhythmic growth in C3 and C4 plants. We propose to use rhythmicity in daily growth patterns to drive the discovery of regulatory network modules controlling biomass accumulation.

  2. Mean body temperature does not modulate eccrine sweat rate during upright tilt.

    PubMed

    Wilson, Thad E; Cui, Jian; Crandall, Craig G

    2005-04-01

    Conflicting reports exist about the role of baroreflexes in efferent control of eccrine sweat rate. These conflicting reports may be due to differing mean body temperatures between studies. The purpose of this project was to test the hypothesis that mean body temperature modulates the effect of head-up tilt on sweat rate and skin sympathetic nerve activity (SSNA). To address this question, mean body temperature (0.9.internal temperature + 0.1.mean skin temperature), SSNA (microneurography of peroneal nerve, n = 8), and sweat rate (from an area innervated by the peroneal nerve and from two forearm sites, one perfused with neostigmine to augment sweating at lower mean body temperatures and the second with the vehicle, n = 12) were measured in 13 subjects during multiple 30 degrees head-up tilts during whole body heating. At the end of the heat stress, mean body temperature (36.8 +/- 0.1 to 38.0 +/- 0.1 degrees C) and sweat rate at all sites were significantly elevated. No significant correlations were observed between mean body temperature and the change in SSNA during head-up tilt (r = 0.07; P = 0.62), sweating within the innervated area (r = 0.06; P = 0.56), sweating at the neostigmine treated site (r = 0.04; P = 0.69), or sweating at the control site (r = 0.01; P = 0.94). Also, for each tilt throughout the heat stress, there were no significant differences in sweat rate (final tilt sweat rates were 0.69 +/- 0.11 and 0.68 +/- 0.11 mg.cm(-2).min(-1) within the innervated area; 1.04 +/- 0.16 and 1.06 +/- 0.16 mg.cm(-2).min(-1) at the neostigmine-treated site; and 0.85 +/- 0.15 and 0.85 +/- 0.15 mg.cm(-2).min(-1) at the control site, for supine and tilt, respectively). Hence, these data indicate that mean body temperature does not modulate eccrine sweat rate during baroreceptor unloading induced via 30 degrees head-up tilt.

  3. Molecular mechanism of circadian rhythmicity of seizures in temporal lobe epilepsy.

    PubMed

    Cho, Chang-Hoon

    2012-01-01

    The circadian pattern of seizures in people with epilepsy (PWE) was first described two millennia ago. However, these phenomena have not received enough scientific attention, possibly due to the lack of promising hypotheses to address the interaction between seizure generation and a physiological clock. To propose testable hypotheses at the molecular level, interactions between circadian rhythm, especially transcription factors governing clock genes expression, and the mTOR (mammalian target of rapamycin) signaling pathway, the major signaling pathway in epilepsy, will be reviewed. Then, two closely related hypotheses will be proposed: (1) Rhythmic activity of hyperactivated mTOR signaling molecules results in rhythmic increases in neuronal excitability. These rhythmic increases in excitability periodically exceed the seizure threshold, displaying the behavioral seizures. (2) Oscillation of neuronal excitability in SCN modulates the rhythmic excitability in the hippocampus through subiculum via long-range projections. Findings from published results, their implications, and proposals for new experiments will be discussed. These attempts may ignite further discussion on what we still need to learn about the rhythmicity of spontaneous seizures.

  4. Basal body reorientation mediated by a Ca2+-modulated contractile protein

    PubMed Central

    1987-01-01

    A rapid, Ca2+-dependent change in the angle between basal bodies (up to 180 degrees) is associated with light-induced reversal of swimming direction (the "photophobic" response) in a number of flagellated green algae. In isolated, detergent-extracted, reactivated flagellar apparatus complexes of Spermatozopsis similis, axonemal beat form conversion to the symmetrical/undulating flagellar pattern and basal body reorientation (from the antiparallel to the parallel configuration) are simultaneously induced at greater than or equal to 10(-7) M Ca2+. Basal body reorientation, however, is independent of flagellar beating since it is induced at greater than or equal to 10(- 7) M Ca2+ when flagellar beating is inhibited (i.e., in the presence of 1 microM orthovanadate in reactivation solutions; in the absence of ATP or dithiothreitol in isolation and reactivation solutions), or when axonemes are mechanically removed from flagellar apparatuses. Although frequent axonemal beat form reversals were induced by varying the Ca2+ concentration, antiparallel basal body configuration could not be restored in isolated flagellar apparatuses. Observations of the photophobic response in vivo indicate that even though the flagella resume the asymmetric, breaststroke beat form 1-2 s after photostimulation, antiparallel basal body configuration is not restored until a few minutes later. Using an antibody generated against the 20- kD Ca2+-modulated contractile protein of striated flagellar roots of Tetraselmis striata (Salisbury, J. L., A. Baron, B. Surek, and M. Melkonian, 1984, J. Cell Biol., 99:962-970), we have found the distal connecting fiber of Spermatozopsis similis to be immunoreactive by indirect immunofluorescence and immunogold electron microscopy. Electrophoretic and immunoblot analysis indicates that the antigen of S. similis flagellar apparatuses consists, like the Tetraselmis protein, of two acidic isoforms of 20 kD. We conclude that the distal basal body connecting fiber is

  5. Postural trials: expertise in rhythmic gymnastics increases control in lateral directions.

    PubMed

    Calavalle, A R; Sisti, D; Rocchi, M B L; Panebianco, R; Del Sal, M; Stocchi, V

    2008-11-01

    The first aim of this paper was to investigate if expertise in rhythmic gymnastics influences postural performance even in an easy non-specific task such as bipedal posture. Rhythmic gymnastics is a unique female sport which encompasses aspects of both artistic gymnastics and ballet and includes the use of a small apparatus (rope, hoop, ball, clubs and ribbon). Most previous studies have shown that expertise achieved by artistic gymnasts and dancers improves postural steadiness only in the situations for which those athletes are trained. Literature has not yet compared rhythmic gymnasts to other athletes in terms of their postural strategies. Hence, the study presented herein tested a group of high level rhythmic gymnasts and a group of female university students, trained in other sports, in the bipedal posture under eyes open and closed conditions. A force platform was used to record body sway. (1) Distance from the centre of sway, (2) lateral and (3) antero-posterior displacements were analyzed in time and frequency domains. Comparing the two groups, it was found that rhythmic gymnasts had better strategies than students in simple postural tasks, especially in lateral directions and in the period from 0.05 to 2 s. The most interesting finding in this study is that rhythmic gymnastics training seems to have a direct effect on the ability to maintain bipedal posture, which may confirm the "transfer" hypothesis of rhythmic gymnastics expertise to bipedal postural sway, especially in medio-lateral displacements. This finding has never been reported in previous studies on artistic gymnasts and ballet dancers. Furthermore, the present study confirmed the visual dependence of all the athletes, irrespective of their disciplines, in their postural trials.

  6. Visual assessment of the radiation distribution in the ISS Lab module: visualization in the human body

    NASA Technical Reports Server (NTRS)

    Saganti, P. B.; Zapp, E. N.; Wilson, J. W.; Cucinotta, F. A.

    2001-01-01

    The US Lab module of the International Space Station (ISS) is a primary working area where the crewmembers are expected to spend majority of their time. Because of the directionality of radiation fields caused by the Earth shadow, trapped radiation pitch angle distribution, and inherent variations in the ISS shielding, a model is needed to account for these local variations in the radiation distribution. We present the calculated radiation dose (rem/yr) values for over 3,000 different points in the working area of the Lab module and estimated radiation dose values for over 25,000 different points in the human body for a given ambient radiation environment. These estimated radiation dose values are presented in a three dimensional animated interactive visualization format. Such interactive animated visualization of the radiation distribution can be generated in near real-time to track changes in the radiation environment during the orbit precession of the ISS.

  7. [Role of rhythmicity in infant development].

    PubMed

    Ciccone, A

    2015-09-01

    This article deals with rhythm in the experiences of infants, focusing in particular on the function of rhythmicity in the baby's sense of being and its continuity. Infants are inevitably subjected to experiences of discontinuity. These experiences are necessary to development, but they expose the child to chaotic experiences when a basic rhythmicity is not ensured. The rhythmicity of childcare experiences gives the illusion of permanence and enables anticipation. This nourishes the basic feeling of security and supports the development of thought. Interactive and intersubjective exchanges must be rhythmic and must be in keeping with the rhythm of the baby, who needs to withdraw regularly from the interaction to internalize the experience of the exchange. Without this retreat, the interaction is over-stimulating and prevents internalization. Object presence/ absence must also be rhythmic, to enable the infant to keep the object alive inside him/ herself. Observation of babies has demonstrated their ability to manage experiences of discontinuity: they are able to sustain a continuous link via their gaze, look for clues indicating the presence of a lost object, search for support in sensations, and fabricate rhythmicity to remain open to the self and the world. The author gives some examples of infant observations that provide evidence of these capacities. One observation shows how a baby defends itself against a discontinuity by actively maintaining a link via his/her gaze. Another example shows an infant holding on to "hard sensations" in order to stay away from "soft" ones, which represent the fragility of the separation experience. This example pertains to a seven-month-old's prelanguage and "prosodic tonicity". The author takes this opportunity to propose the notion of "psychic bisensuality" to describe these two sensation poles, which must be harmoniously articulated to guarantee an inner sense of security. Such repairs of discontinuity are only possible if the

  8. An Exploration of Rhythmic Grouping of Speech Sequences by French- and German-Learning Infants

    PubMed Central

    Abboub, Nawal; Boll-Avetisyan, Natalie; Bhatara, Anjali; Höhle, Barbara; Nazzi, Thierry

    2016-01-01

    Rhythm in music and speech can be characterized by a constellation of several acoustic cues. Individually, these cues have different effects on rhythmic perception: sequences of sounds alternating in duration are perceived as short-long pairs (weak-strong/iambic pattern), whereas sequences of sounds alternating in intensity or pitch are perceived as loud-soft, or high-low pairs (strong-weak/trochaic pattern). This perceptual bias—called the Iambic-Trochaic Law (ITL)–has been claimed to be an universal property of the auditory system applying in both the music and the language domains. Recent studies have shown that language experience can modulate the effects of the ITL on rhythmic perception of both speech and non-speech sequences in adults, and of non-speech sequences in 7.5-month-old infants. The goal of the present study was to explore whether language experience also modulates infants’ grouping of speech. To do so, we presented sequences of syllables to monolingual French- and German-learning 7.5-month-olds. Using the Headturn Preference Procedure (HPP), we examined whether they were able to perceive a rhythmic structure in sequences of syllables that alternated in duration, pitch, or intensity. Our findings show that both French- and German-learning infants perceived a rhythmic structure when it was cued by duration or pitch but not intensity. Our findings also show differences in how these infants use duration and pitch cues to group syllable sequences, suggesting that pitch cues were the easier ones to use. Moreover, performance did not differ across languages, failing to reveal early language effects on rhythmic perception. These results contribute to our understanding of the origin of rhythmic perception and perceptual mechanisms shared across music and speech, which may bootstrap language acquisition. PMID:27378887

  9. An Exploration of Rhythmic Grouping of Speech Sequences by French- and German-Learning Infants.

    PubMed

    Abboub, Nawal; Boll-Avetisyan, Natalie; Bhatara, Anjali; Höhle, Barbara; Nazzi, Thierry

    2016-01-01

    Rhythm in music and speech can be characterized by a constellation of several acoustic cues. Individually, these cues have different effects on rhythmic perception: sequences of sounds alternating in duration are perceived as short-long pairs (weak-strong/iambic pattern), whereas sequences of sounds alternating in intensity or pitch are perceived as loud-soft, or high-low pairs (strong-weak/trochaic pattern). This perceptual bias-called the Iambic-Trochaic Law (ITL)-has been claimed to be an universal property of the auditory system applying in both the music and the language domains. Recent studies have shown that language experience can modulate the effects of the ITL on rhythmic perception of both speech and non-speech sequences in adults, and of non-speech sequences in 7.5-month-old infants. The goal of the present study was to explore whether language experience also modulates infants' grouping of speech. To do so, we presented sequences of syllables to monolingual French- and German-learning 7.5-month-olds. Using the Headturn Preference Procedure (HPP), we examined whether they were able to perceive a rhythmic structure in sequences of syllables that alternated in duration, pitch, or intensity. Our findings show that both French- and German-learning infants perceived a rhythmic structure when it was cued by duration or pitch but not intensity. Our findings also show differences in how these infants use duration and pitch cues to group syllable sequences, suggesting that pitch cues were the easier ones to use. Moreover, performance did not differ across languages, failing to reveal early language effects on rhythmic perception. These results contribute to our understanding of the origin of rhythmic perception and perceptual mechanisms shared across music and speech, which may bootstrap language acquisition.

  10. Rhythmic movement disorder (head banging) in an adult during rapid eye movement sleep.

    PubMed

    Anderson, Kirstie N; Smith, Ian E; Shneerson, John M

    2006-06-01

    Sleep-related rhythmic movements (head banging or body rocking) are extremely common in normal infants and young children, but less than 5% of children over the age of 5 years old exhibit these stereotyped motor behaviors. They characteristically occur during drowsiness or sleep onset rather than in deep sleep or rapid eye movement (REM) sleep. We present a 27-year-old man with typical rhythmic movement disorder that had persisted into adult life and was restricted to REM sleep. This man is the oldest subject with this presentation reported to date and highlights the importance of recognizing this nocturnal movement disorder when it does occur in adults.

  11. Volumetric-Modulated Arc Therapy for Stereotactic Body Radiotherapy of Lung Tumors: A Comparison With Intensity-Modulated Radiotherapy Techniques

    SciTech Connect

    Holt, Andrea; Vliet-Vroegindeweij, Corine van; Mans, Anton; Belderbos, Jose S.; Damen, Eugene M.F.

    2011-12-01

    Purpose: To demonstrate the potential of volumetric-modulated arc therapy (VMAT) compared with intensity-modulated radiotherapy (IMRT) techniques with a limited number of segments for stereotactic body radiotherapy (SBRT) for early-stage lung cancer. Methods and Materials: For a random selection of 27 patients eligible for SBRT, coplanar and noncoplanar IMRT and coplanar VMAT (using SmartArc) treatment plans were generated in Pinnacle{sup 3} and compared. In addition, film measurements were performed using an anthropomorphic phantom to evaluate the skin dose for the different treatment techniques. Results: Using VMAT, the delivery times could be reduced to an average of 6.6 min compared with 23.7 min with noncoplanar IMRT. The mean dose to the healthy lung was 4.1 Gy for VMAT and noncoplanar IMRT and 4.2 Gy for coplanar IMRT. The volume of healthy lung receiving >5 Gy and >20 Gy was 18.0% and 5.4% for VMAT, 18.5% and 5.0% for noncoplanar IMRT, and 19.4% and 5.7% for coplanar IMRT, respectively. The dose conformity at 100% and 50% of the prescribed dose of 54 Gy was 1.13 and 5.17 for VMAT, 1.11 and 4.80 for noncoplanar IMRT and 1.12 and 5.31 for coplanar IMRT, respectively. The measured skin doses were comparable for VMAT and noncoplanar IMRT and slightly greater for coplanar IMRT. Conclusions: Coplanar VMAT for SBRT for early-stage lung cancer achieved plan quality and skin dose levels comparable to those using noncoplanar IMRT and slightly better than those with coplanar IMRT. In addition, the delivery time could be reduced by {<=}70% with VMAT.

  12. Daily rhythmicity and hibernation in the Anatolian ground squirrel under natural and laboratory conditions.

    PubMed

    Kart Gür, Mutlu; Refinetti, Roberto; Gür, Hakan

    2009-02-01

    We studied daily rhythmicity of body temperature (T(b)) before and during hibernation in Anatolian ground squirrels (Spermophilus xanthoprymnus) under natural and laboratory conditions using surgically implanted temperature loggers. Under both conditions, robust daily T(b) rhythmicity with parameters comparable to those of other ground squirrel species was observed before but not during hibernation. Euthermic animals had robust daily T(b) rhythms with a mean of 37.0 degrees C and a range of excursion of approximately 4 degrees C. No T(b) rhythm was detected during torpor bouts, either because T(b) rhythmicity was absent or because the daily range of excursion was smaller than 0.2 degrees C. The general patterns of hibernation that we observed in Anatolian ground squirrels were similar to those previously observed by other investigators in other species of ground squirrels.

  13. Modulation of orthogonal body waves enables high maneuverability in sidewinding locomotion

    NASA Astrophysics Data System (ADS)

    Astley, Henry; Gong, Chaohui; Travers, Matt; Serrano, Miguel; Vela, Patricio; Choset, Howie; Mendelson, Joseph, III; Hu, David; Goldman, Daniel

    2015-03-01

    To simplify control of high degree of freedom bodies, organisms may target a set of simple shape changes (a ``template''). Recent work has revealed that the locomotion of sidewinder rattlesnakes can be described by a combination of horizontal and vertical body waves with a phase difference of +/- π/2, representing a possible control template. These animals display high maneuverability which we hypothesize emerges from their ability to independently modulate these waves. Snakes used two distinct turning methods which we term differential turning (24° turn per cycle) and reversal turning (80°). Kinematic data suggested that during differential turning the animals imposed an amplitude modulation in the horizontal wave while in reversal turning they shifted the phase of the vertical wave by π. We tested these mechanisms in the robot, generating differential and reversal turning. Further manipulations of the two-wave system revealed a third turning mode, ``frequency turning,'' not observed in biological snakes which allowed the robot to execute large (127°) in-place turns. The two-wave system enables unprecedented maneuverability of high degree-of-freedom systems, revealing a practical benefits of the search for control templates. Zoo Atlanta

  14. Chemosensory danger detection in the human brain: Body odor communicating aggression modulates limbic system activation.

    PubMed

    Mutic, Smiljana; Brünner, Yvonne F; Rodriguez-Raecke, Rea; Wiesmann, Martin; Freiherr, Jessica

    2017-02-28

    Although the sense of smell is involved in numerous survival functions, the processing of body odor emitted by dangerous individuals is far from understood. The aim of the study was to explore how human fight chemosignals communicating aggression can alter brain activation related to an attentional bias and danger detection. While the anterior cingulate cortex (ACC) was seen involved in processing threat-related emotional information, danger detection and error evaluation, it still remains unknown whether human chemosignals communicating aggression can potentially modulate this activation. In the fMRI experiment, healthy male and female normosmic odor recipients (n=18) completed a higher-order processing task (emotional Stroop task with the word categories anger, anxiety, happiness and neutral) while exposed to aggression and exercise chemosignals (collected from a different group of healthy male donors; n=16). Our results provide first evidence that aggression chemosignals induce a time-sensitive attentional bias in chemosensory danger detection and modulate limbic system activation. During exposure to aggression chemosignals compared to exercise chemosignals, functional imaging data indicates an enhancement of thalamus, hypothalamus and insula activation (p<.05, FWE-corrected). Together with the thalamus, the ACC was seen activated in response to threat-related words (p<.001). Chemosensory priming and habituation to body odor signals are discussed.

  15. Color of hot soup modulates postprandial satiety, thermal sensation, and body temperature in young women.

    PubMed

    Suzuki, Maki; Kimura, Rie; Kido, Yasue; Inoue, Tomoko; Moritani, Toshio; Nagai, Narumi

    2017-04-01

    The color of food is known to modulate not only consumers' motivation to eat, but also thermal perception. Here we investigated whether the colors of hot soup can influence thermal sensations and body temperature, in addition to the food acceptability and appetite. Twelve young female participants consumed commercial white potage soup, modified to yellow or blue by adding food dyes, at 9 a.m. on 3 separated days. During the test, visual impression (willingness to eat, palatability, comfort, warmth, and anxiety) and thermal sensations were self-reported using visual analog scales. Core (intra-aural) and peripheral (toe) temperatures were continuously recorded 10 min before and 60 min after ingestion. Blue soup significantly decreased willingness to eat, palatability, comfort, and warmth ratings, and significantly increased anxiety feelings compared to the white and yellow soups. After ingestion, the blue soup showed significantly smaller satiety ratings and the tendency of lower thermal sensation scores of the whole body compared to the white and yellow soups. Moreover, a significantly greater increase in toe temperature was found with the yellow soup than the white or blue soup. In conclusion, this study provides new evidence that the colors of hot food may modulate postprandial satiety, thermal sensations and peripheral temperature. Such effects of color may be useful for dietary strategies for individuals who need to control their appetite.

  16. Somatosensory driven interpersonal synchrony during rhythmic sway.

    PubMed

    Sofianidis, George; Hatzitaki, Vassilia; Grouios, George; Johannsen, Leif; Wing, Alan

    2012-06-01

    Spontaneous synchrony emerges between individuals performing together rhythmic activities while communicating by means of sensory feedback. In this study, we examined the nature of interpersonal synchrony mediated by light fingertip contact when individuals sway rhythmically in the sagittal plane. The effect of traditional dance expertise on interpersonal synchrony was investigated. Sixty participants (30 dancers, 30 novices) formed three types of couples (10 expert couples, 10 novice couples, 10 mixed couples) and performed a rhythmical sway task (40s) that was either self or metronome paced (frequency: 0.25Hz). Cross spectral analysis of the center of pressure (CoP) displacement signals revealed that during self-paced sway fingertip contact evoked a decrease of the dominant sway frequency difference between partners, an increase in the coherence between the sway signals and a concentration of relative phase angles towards the in-phase (0°-20°) region. In metronome paced sway however, only expert dancers were able to benefit from haptic contact to further improve interpersonal synchrony. These findings suggest that haptic contact can stabilize the spontaneous coordination dynamics of two persons performing rhythmic sway together. The strength of the emerged synchrony depends on the individuals' expertise to integrate tactile and auditory information about sway.

  17. An Update on the Rhythmic Arts Project

    ERIC Educational Resources Information Center

    Tuduri, Eddie

    2008-01-01

    The Rhythmic Arts Project (TRAP) is touching the lives of typical children and adults with various disabilities all over the world and now has programs in two Bulgarian orphanages, day programs in Australia, and, most recently, in the general hospital in Johannesburg, South Africa. TRAP is also currently approaching facilities in more than 20…

  18. Encoding and Retrieval During Bimanual Rhythmic Coordination

    ERIC Educational Resources Information Center

    Shockley, Kevin; Turvey, Michael T.

    2005-01-01

    In 2 experiments, bimanual 1:1 rhythmic coordination was performed concurrently with encoding or retrieval of word lists. Effects of divided attention (DA) on coordination were indexed by changes in mean relative phase and recurrence measures of shared activity between the 2 limbs. Effects of DA on memory were indexed by deficits in recall…

  19. Entrainment and the cranial rhythmic impulse.

    PubMed

    McPartland, J M; Mein, E A

    1997-01-01

    Entrainment is the integration or harmonization of oscillators. All organisms pulsate with myriad electrical and mechanical rhythms. Many of these rhythms emanate from synchronized pulsating cells (eg, pacemaker cells, cortical neurons). The cranial rhythmic impulse is an oscillation recognized by many bodywork practitioners, but the functional origin of this impulse remains uncertain. We propose that the cranial rhythmic impulse is the palpable perception of entrainment, a harmonic frequency that incorporates the rhythms of multiple biological oscillators. It is derived primarily from signals between the sympathetic and parasympathetic nervous systems. Entrainment also arises between organisms. The harmonizing of coupled oscillators into a single, dominant frequency is called frequency-selective entrainment. We propose that this phenomenon is the modus operandi of practitioners who use the cranial rhythmic impulse in craniosacral treatment. Dominant entrainment is enhanced by "centering," a technique practiced by many healers, for example, practitioners of Chinese, Tibetan, and Ayurvedic medicine. We explore the connections between centering, the cranial rhythmic impulse, and craniosacral treatment.

  20. Rhythmic Characteristics of Colloquial and Formal Tamil

    ERIC Educational Resources Information Center

    Keane, Elinor

    2006-01-01

    Application of recently developed rhythmic measures to passages of read speech in colloquial and formal Tamil revealed some significant differences between the two varieties, which are in diglossic distribution. Both were also distinguished from a set of control data from British English speakers reading an equivalent passage. The findings have…

  1. Modulation of orthogonal body waves enables high maneuverability in sidewinding locomotion

    PubMed Central

    Astley, Henry C.; Gong, Chaohui; Dai, Jin; Travers, Matthew; Serrano, Miguel M.; Vela, Patricio A.; Choset, Howie; Mendelson, Joseph R.; Hu, David L.; Goldman, Daniel I.

    2015-01-01

    Many organisms move using traveling waves of body undulation, and most work has focused on single-plane undulations in fluids. Less attention has been paid to multiplane undulations, which are particularly important in terrestrial environments where vertical undulations can regulate substrate contact. A seemingly complex mode of snake locomotion, sidewinding, can be described by the superposition of two waves: horizontal and vertical body waves with a phase difference of ±90°. We demonstrate that the high maneuverability displayed by sidewinder rattlesnakes (Crotalus cerastes) emerges from the animal’s ability to independently modulate these waves. Sidewinder rattlesnakes used two distinct turning methods, which we term differential turning (26° change in orientation per wave cycle) and reversal turning (89°). Observations of the snakes suggested that during differential turning the animals imposed an amplitude modulation in the horizontal wave whereas in reversal turning they shifted the phase of the vertical wave by 180°. We tested these mechanisms using a multimodule snake robot as a physical model, successfully generating differential and reversal turning with performance comparable to that of the organisms. Further manipulations of the two-wave system revealed a third turning mode, frequency turning, not observed in biological snakes, which produced large (127°) in-place turns. The two-wave system thus functions as a template (a targeted motor pattern) that enables complex behaviors in a high-degree-of-freedom system to emerge from relatively simple modulations to a basic pattern. Our study reveals the utility of templates in understanding the control of biological movement as well as in developing control schemes for limbless robots. PMID:25831489

  2. Automatic recognition and scoring of olympic rhythmic gymnastic movements.

    PubMed

    Díaz-Pereira, M Pino; Gómez-Conde, Iván; Escalona, Merly; Olivieri, David N

    2014-04-01

    We describe a conceptually simple algorithm for assigning judgement scores to rhythmic gymnastic movements, which could improve scoring objectivity and reduce judgemental bias during competitions. Our method, implemented as a real-time computer vision software, takes a video shot or a live performance video stream as input and extracts detailed velocity field information from body movements, transforming them into specialized spatio-temporal image templates. The collection of such images over time, when projected into a velocity covariance eigenspace, trace out unique but similar trajectories for a particular gymnastic movement type. By comparing separate executions of the same atomic gymnastic routine, our method assigns a quality judgement score that is related to the distance between the respective spatio-temporal trajectories. For several standard gymnastic movements, the method accurately assigns scores that are comparable to those assigned by expert judges. We also describe our rhythmic gymnastic video shot database, which we have made freely available to the human movement research community. The database can be obtained at http://www.milegroup.net/apps/gymdb/.

  3. The awareness of body orientation modulates the perception of visual vertical.

    PubMed

    Barra, Julien; Pérennou, Dominic; Thilo, Kail V; Gresty, Michael A; Bronstein, Adolfo M

    2012-08-01

    It is established that the body position influences verticality perception. In contrast, the possible influence of the awareness of the body orientation on verticality perception has never been investigated. This hypothesis, explored in the present study, is supported by the role played by the parietal cortex and the insula in both body position awareness and verticality perception. Nine subjects were asked to estimate the direction of the visual vertical (VV) by 12 adjustments of a luminous line in three conditions: (1) a control condition (subjects were upright and aware of their position), (2) a condition of congruence between the lateral body tilt and the awareness of this tilt, and (3) a condition of dissociation of subjective and objective orientations (tilted subjects who felt upright). The dissociation between objective and subjective orientations was obtained by inducing experimentally a postural vertical (PV) bias through 5 min of lateral body tilt at 30° in darkness in a motorized flight simulator (mean 8.8° ± 4; min 6.2°; max 17.4°). VV orientation and variability were measured (expressed below in this order). As compared to the upright condition (0.3° ± 0.2; 0.8° ± 0.5), subjects showed similar VV orientation (0.1° ± 0.6; p=0.82) but an increased variability (1.4°±0.5; p<0.001) when tilted and aware of their tilt. In contrast, when they were tilted but felt upright, VV was biased in the direction of body tilt (2°±0.5; p<0.005) without increase of variability (0.9° ± 0.5; p=0.7). Our study reveals that the awareness of body orientation modulates verticality representation, which means that in addition to sensory integration, mental processes play also a role in the sense of verticality. We propose a novel model of verticality representation, based both on bottom-up and top-down processes.

  4. Different types of theta rhythmicity are induced by social and fearful stimuli in a network associated with social memory

    PubMed Central

    Tendler, Alex; Wagner, Shlomo

    2015-01-01

    Rhythmic activity in the theta range is thought to promote neuronal communication between brain regions. In this study, we performed chronic telemetric recordings in socially behaving rats to monitor electrophysiological activity in limbic brain regions linked to social behavior. Social encounters were associated with increased rhythmicity in the high theta range (7–10 Hz) that was proportional to the stimulus degree of novelty. This modulation of theta rhythmicity, which was specific for social stimuli, appeared to reflect a brain-state of social arousal. In contrast, the same network responded to a fearful stimulus by enhancement of rhythmicity in the low theta range (3–7 Hz). Moreover, theta rhythmicity showed different pattern of coherence between the distinct brain regions in response to social and fearful stimuli. We suggest that the two types of stimuli induce distinct arousal states that elicit different patterns of theta rhythmicity, which cause the same brain areas to communicate in different modes. DOI: http://dx.doi.org/10.7554/eLife.03614.001 PMID:25686218

  5. Harmonic Analysis for Optically Modulating Bodies Using the Harmonic Structure Function

    NASA Astrophysics Data System (ADS)

    Dikeman, R. D.; Lin, S.; Kim, C.

    Lockheed Martin Hawaii presents a novel signal processing algorithm for focal plane array processing. We introduce the Harmonic Structure Function (HSF) and demonstrate its capability in detecting, classifying and counting rotating bodies in a single pixel. The HSF has a powerful use in dynamical situations occurring on scales less than the single pixel solid angle. The work presented here is making a major impact in the Missile Defense Agency's Project Hercules Forward Based Sensor (FBS) group but the results presented here is shown in an unclassified form. First, the HSF algorithm is detailed. The origin of the HSF is in the ASW (AntiSubmarine Warfare) acoustic processing domain and the analogy to the focal plane is given. Next, the mathematical definition of the HSF and the natural extension from integral to discrete form is detailed. Thereafter, additional harmonic processing techniques such as the so-called 'sidelobe' reduction are explained. These techniques are powerful methods to determine the fundamental frequency of a given rotating body that can have various harmonically related narrow band tonal structures. Simulations of rotating bodies and modulating reflectance used for analysis are then discussed. These simulations result in the construction of time series data for rotating bodies with fundamental frequencies in noisy backgrounds. The HSF is then used to analyze these fidelity simulations. It is shown that the HSF is capable of detecting, classifying and countingobjects on a single pixel. Finally, the robustness of the algorithm is analyzed and it is shown that the number of detectable objects is dependent on sample rate, target temporal extent, and other factors. This analysis yield important considerations for sensor developers and operators.

  6. Rhythmic control of endocannabinoids in the rat pineal gland.

    PubMed

    Koch, Marco; Ferreirós, Nerea; Geisslinger, Gerd; Dehghani, Faramarz; Korf, Horst-Werner

    2015-01-01

    Endocannabinoids modulate neuroendocrine networks by directly targeting cannabinoid receptors. The time-hormone melatonin synchronizes these networks with external light condition and guarantees time-sensitive and ecologically well-adapted behaviors. Here, the endocannabinoid arachidonoyl ethanolamide (AEA) showed rhythmic changes in rat pineal glands with higher levels during the light-period and reduced amounts at the onset of darkness. Norepinephrine, the essential stimulus for nocturnal melatonin biosynthesis, acutely down-regulated AEA and other endocannabinoids in cultured pineal glands. These temporal dynamics suggest that AEA exerts time-dependent autocrine and/or paracrine functions within the pineal. Moreover, endocananbinoids may be released from the pineal into the CSF or blood stream.

  7. Dosimetric aspects of inverse-planned modulated-arc total-body irradiation

    SciTech Connect

    Held, Mareike; Kirby, Neil; Morin, Olivier; Pouliot, Jean

    2012-08-15

    Purpose: To develop optimal beam parameters and to verify the dosimetric aspects of the recently developed modulated-arc total-body irradiation (MATBI) technique, which delivers an inverse-planned dose to the entire body using gantry rotation. Methods: The patient is positioned prone and supine underneath the gantry at about 2 m source-to-surface distance (SSD). Then, up to 28 beams irradiate the patient from different gantry angles. Based on full-body computed-tomography (CT) images of the patient, the weight of each beam is optimized, using inverse planning, to create a uniform body dose. This study investigates how to best simulate patients and the ideal beam setup parameters, such as field size, number of beams, and beam geometry, for treatment time and dose homogeneity. In addition, three anthropomorphic water phantoms were constructed and utilized to verify the accuracy of dose delivery, with both diode array and ion chamber measurements. Furthermore, to improve the accuracy of the new technique, a beam model is created specifically for the extended-SSD positioning for MATBI. Results: Low dose CT scans can be utilized for dose calculations without affecting the accuracy. The largest field size of 40 Multiplication-Sign 40 cm{sup 2} was found to deliver the most uniform dose in the least amount of time. Moreover, a higher number of beams improves dose homogeneity. The average dose discrepancy between ion chamber measurements and extended-SSD beam model calculations was 1.2%, with the largest discrepancy being 3.2%. This average dose discrepancy was 1.4% with the standard beam model for delivery at isocenter. Conclusions: The optimum beam setup parameters, regarding dose uniformity and treatment duration, are laid out for modulated-arc TBI. In addition, the presented dose measurements show that these treatments can be delivered accurately. These measurements also indicated that a new beam model did not significantly improve the accuracy of dose calculations

  8. Exercise modality modulates body temperature regulation during exercise in uncompensable heat stress.

    PubMed

    Schlader, Zachary J; Raman, Aaron; Morton, R Hugh; Stannard, Stephen R; Mündel, Toby

    2011-05-01

    This study evaluated exercise modality [i.e. self-paced (SP) or fixed-intensity (FI) exercise] as a modulator of body temperature regulation under uncompensable heat stress. Eight well-trained male cyclists completed (work-matched) FI and SP cycling exercise bouts in a hot (40.6 ± 0.2°C) and dry (relative humidity 23 ± 3%) environment estimated to elicit 70% of [Formula: see text]O(2)max. Exercise intensity (i.e. power output) decreased over time in SP, which resulted in longer exercise duration (FI 20.3 ± 3.4 min, SP 23.2 ± 4.1 min). According to the heat strain index, the modification of exercise intensity in SP improved the compensability of the thermal environment which, relative to FI, was likely a result of the reductions in metabolic heat production (i.e. [Formula: see text]O(2)). Consequently, the rate of rise in core body temperature was higher in FI (0.108 ± 0.020°C/min) than in SP (0.082 ± 0.016°C/min). Interestingly, cardiac output, stroke volume, and heart rate during exercise were independent of exercise modality. However, core body temperature (FI 39.4 ± 0.3°C, SP 39.1 ± 0.4°C), blood lactate (FI 2.9 ± 0.8 mmol/L, SP 2.3 ± 0.7 mmol/L), perceived exertion (FI 18 ± 2, SP 16 ± 2), and physiological strain (FI 9.1 ± 0.9, SP 8.3 ± 1.1) were all higher in FI compared to SP at exhaustion/completion. These findings indicate that, when exercise is SP, behavioral modification of metabolic heat production improves the compensability of the thermal environment and reduces thermoregulatory strain. Therefore, under uncompensable heat stress, exercise modality modulates body temperature regulation.

  9. Electric light, particularly at night, disrupts human circadian rhythmicity: is that a problem?

    PubMed Central

    Stevens, Richard G.; Zhu, Yong

    2015-01-01

    Over the past 3 billion years, an endogenous circadian rhythmicity has developed in almost all life forms in which daily oscillations in physiology occur. This allows for anticipation of sunrise and sunset. This physiological rhythmicity is kept at precisely 24 h by the daily cycle of sunlight and dark. However, since the introduction of electric lighting, there has been inadequate light during the day inside buildings for a robust resetting of the human endogenous circadian rhythmicity, and too much light at night for a true dark to be detected; this results in circadian disruption and alters sleep/wake cycle, core body temperature, hormone regulation and release, and patterns of gene expression throughout the body. The question is the extent to which circadian disruption compromises human health, and can account for a portion of the modern pandemics of breast and prostate cancers, obesity, diabetes and depression. As societies modernize (i.e. electrify) these conditions increase in prevalence. There are a number of promising leads on putative mechanisms, and epidemiological findings supporting an aetiologic role for electric lighting in disease causation. These include melatonin suppression, circadian gene expression, and connection of circadian rhythmicity to metabolism in part affected by haem iron intake and distribution. PMID:25780233

  10. Electric light, particularly at night, disrupts human circadian rhythmicity: is that a problem?

    PubMed

    Stevens, Richard G; Zhu, Yong

    2015-05-05

    Over the past 3 billion years, an endogenous circadian rhythmicity has developed in almost all life forms in which daily oscillations in physiology occur. This allows for anticipation of sunrise and sunset. This physiological rhythmicity is kept at precisely 24 h by the daily cycle of sunlight and dark. However, since the introduction of electric lighting, there has been inadequate light during the day inside buildings for a robust resetting of the human endogenous circadian rhythmicity, and too much light at night for a true dark to be detected; this results in circadian disruption and alters sleep/wake cycle, core body temperature, hormone regulation and release, and patterns of gene expression throughout the body. The question is the extent to which circadian disruption compromises human health, and can account for a portion of the modern pandemics of breast and prostate cancers, obesity, diabetes and depression. As societies modernize (i.e. electrify) these conditions increase in prevalence. There are a number of promising leads on putative mechanisms, and epidemiological findings supporting an aetiologic role for electric lighting in disease causation. These include melatonin suppression, circadian gene expression, and connection of circadian rhythmicity to metabolism in part affected by haem iron intake and distribution.

  11. Rhythmic leptin is required for weight gain from circadian desynchronized feeding in the mouse.

    PubMed

    Arble, Deanna Marie; Vitaterna, Martha Hotz; Turek, Fred W

    2011-01-01

    The neuroendocrine and metabolic effects of leptin have been extensively researched since the discovery, and the later identification, of the leptin gene mutated within the ob/ob mouse. Leptin is required for optimal health in a number of physiological systems (e.g. fertility, bone density, body weight regulation). Despite the extensive leptin literature and many observations of leptin's cyclical pattern over the 24-hour day, few studies have specifically examined how the circadian rhythm of leptin may be essential to leptin signaling and health. Here we present data indicating that a rhythmic leptin profile (e.g. 1 peak every 24 hours) leads to excessive weight gain during desynchronized feeding whereas non-rhythmic leptin provided in a continuous manner does not lead to excessive body weight gain under similar feeding conditions. This study suggests that feeding time can interact with leptin's endogenous rhythm to influence metabolic signals, specifically leading to excessive body weight gains during 'wrongly' timed feeding.

  12. Two clusters of GABAergic ellipsoid body neurons modulate olfactory labile memory in Drosophila.

    PubMed

    Zhang, Zhiping; Li, Xiaoting; Guo, Jing; Li, Yan; Guo, Aike

    2013-03-20

    In Drosophila, aversive olfactory memory is believed to be stored in a prominent brain structure, the mushroom body (MB), and two pairs of MB intrinsic neurons, the dorsal paired medial (DPM) and the anterior paired lateral (APL) neurons, are found to regulate the consolidation of middle-term memory (MTM). Here we report that another prominent brain structure, the ellipsoid body (EB), is also involved in the modulation of olfactory MTM. Activating EB R2/R4m neurons does not affect the learning index, but specifically eliminates anesthesia-sensitive memory (ASM), the labile component of olfactory MTM. We further demonstrate that approximately two-thirds of these EB neurons are GABAergic and are responsible for the suppression of ASM. Using GRASP (GFP reconstitution across synaptic partners), we reveal potential synaptic connections between the EB and MB in regions covering both the presynaptic and postsynaptic sites of EB neurons, suggesting the presence of bidirectional connections between these two important brain structures. These findings suggest the existence of direct connections between the MB and EB, and provide new insights into the neural circuit basis for olfactory labile memory in Drosophila.

  13. Rhythmic spontaneous activity in the piriform cortex.

    PubMed

    Sanchez-Vives, Maria V; Descalzo, V F; Reig, R; Figueroa, N A; Compte, A; Gallego, R

    2008-05-01

    Slow spontaneous rhythmic activity is generated and propagates in neocortical slices when bathed in an artificial cerebrospinal fluid with ionic concentrations similar to the ones in vivo. This activity is extraordinarily similar to the activation of the cortex in physiological conditions (e.g., slow-wave sleep), thus representing a unique in vitro model to understand how cortical networks maintain and control ongoing activity. Here we have characterized the activity generated in the olfactory or piriform cortex and endopiriform nucleus (piriform network). Because these structures are prone to generate epileptic discharges, it seems critical to understand how they generate and regulate their physiological rhythmic activity. The piriform network gave rise to rhythmic spontaneous activity consisting of a succession of up and down states at an average frequency of 1.8 Hz, qualitatively similar to the corresponding neocortical activity. This activity originated in the deep layers of the piriform network, which displayed higher excitability and denser connectivity. A remarkable difference with neocortical activity was the speed of horizontal propagation (114 mm/s), one order of magnitude faster in the piriform network. Properties of the piriform cortex subserving fast horizontal propagation may underlie the higher vulnerability of this area to epileptic seizures.

  14. Distinguishing rhythmic from non-rhythmic brain activity during rest in healthy neurocognitive aging.

    PubMed

    Caplan, Jeremy B; Bottomley, Monica; Kang, Pardeep; Dixon, Roger A

    2015-05-15

    Rhythmic brain activity at low frequencies (<12Hz) during rest are thought to increase in neurodegenerative disease, but findings in healthy neurocognitive aging are mixed. Here we address two reasons conventional spectral analyses may have led to inconsistent results. First, spectral-power measures are compared to a baseline condition; when resting activity is the signal of interest, it is unclear what the baseline should be. Second, conventional methods do not clearly differentiate power due to rhythmic versus non-rhythmic activity. The Better OSCillation detection method (BOSC; Caplan et al., 2001; Whitten et al., 2011) avoids these problems by using the signal's own spectral characteristics as a reference to detect elevations in power lasting a few cycles. We recorded electroencephalographic (EEG) signal during rest, alternating eyes open and closed, in healthy younger (18-25 years) and older (60-74 years) participants. Topographic plots suggested the conventional and BOSC analyses measured different sources of activity, particularly at frequencies, like delta (1-4Hz), at which rhythms are sporadic; topographies were more similar in the 8-12Hz alpha band. There was little theta-band activity meeting the BOSC method's criteria, suggesting prior findings of theta power in healthy aging may reflect non-rhythmic signal. In contrast, delta oscillations were present at higher levels than theta in both age groups. In summary, applying strict and standardized criteria for rhythmicity, slow rhythms appear present in the resting brain at delta and alpha, but not theta frequencies, and appear unchanged in healthy aging.

  15. Evidence for histamine as a new modulator of carotid body chemoreception.

    PubMed

    Rio, R Del; Moya, E A; Alcayaga, J; Iturriaga, R

    2009-01-01

    It has been proposed that histamine is an excitatory transmitter between the glomus cells of the carotid body (CB) and the nerve endings of the petrosal ganglion (PG) neurons. The histamine biosynthetic pathway and the presence of histamine H1, H2 and H3 receptors have been reported in the CB. Thus, histamine meets some of the criteria to be regarded as a transmitter. However, there is no evidence that glomus cells contain histamine, or whether its application produces chemosensory excitation. Therefore, we studied its immunocytochemical localization on cat CB and its effects on chemosensory activity. Using perfused and superfused in vitro CB and PG preparations, we assessed the effects of histamine hydrochloride on chemosensory discharges and of histamine H1, H2 and H3 receptor blockers. We found the presence of histamine immunoreactivity in dense-core vesicles in glomus cells. In an in vitro CB preparation we performed pharmacological experiments to characterize histamine effects. The application of histamine hydrochloride (0.5-1,000 microg) to the CB produces a dose-dependent increase in the carotid sinus nerve activity. The H1 receptor blockade with pyrilamine 500 nM produces partial decrease of the histamine-induced response, whereas the H2 receptor blockade (ranitidine 100microM) fail to abolish the histamine excitatory effects. Antagonism of the H3 receptor results in an increase in carotid body chemosensory activity. On the other hand, application of histamine to the isolated PG had no effect on the carotid nerve discharge. Our results suggest that histamine is a modulator of the carotid body chemoreception through H1 and H3 receptor activation.

  16. Rhythmic structure of Hindi and English: new insights from a computational analysis.

    PubMed

    Das, Tanusree; Singh, Latika; Singh, Nandini C

    2008-01-01

    Much information about speech rhythm is believed to be embedded in low frequency temporal modulations of the speech envelope. Using novel methods of spectral analysis we construct a spectro-temporal modulation spectrum and extract low frequency temporal modulations of spoken utterances to study the rhythmic structure of English and Hindi. The results of our spectral analysis reveal a narrower temporal bandwidth for Hindi as compared to English. We also calculate variability in syllable durations and find that variability in English is greater than Hindi. We relate temporal bandwidth of the modulation spectrum to variability in syllable duration and suggest that narrow bandwidth in the modulation spectrum implies less variability, whereas broad bandwidth implies greater variability in syllable duration. Our results also demonstrate that syllabic information is contained in low frequency temporal modulations of the speech envelope. Our results suggest that the modulation spectrum can be explored as a promising tool to study the temporal structure of language.

  17. The Enhanced Musical Rhythmic Perception in Second Language Learners

    PubMed Central

    Roncaglia-Denissen, M. Paula; Roor, Drikus A.; Chen, Ao; Sadakata, Makiko

    2016-01-01

    Previous research suggests that mastering languages with distinct rather than similar rhythmic properties enhances musical rhythmic perception. This study investigates whether learning a second language (L2) contributes to enhanced musical rhythmic perception in general, regardless of first and second languages rhythmic properties. Additionally, we investigated whether this perceptual enhancement could be alternatively explained by exposure to musical rhythmic complexity, such as the use of compound meter in Turkish music. Finally, it investigates if an enhancement of musical rhythmic perception could be observed among L2 learners whose first language relies heavily on pitch information, as is the case with tonal languages. Therefore, we tested Turkish, Dutch and Mandarin L2 learners of English and Turkish monolinguals on their musical rhythmic perception. Participants’ phonological and working memory capacities, melodic aptitude, years of formal musical training and daily exposure to music were assessed to account for cultural and individual differences which could impact their rhythmic ability. Our results suggest that mastering a L2 rather than exposure to musical rhythmic complexity could explain individuals’ enhanced musical rhythmic perception. An even stronger enhancement of musical rhythmic perception was observed for L2 learners whose first and second languages differ regarding their rhythmic properties, as enhanced performance of Turkish in comparison with Dutch L2 learners of English seem to suggest. Such a stronger enhancement of rhythmic perception seems to be found even among L2 learners whose first language relies heavily on pitch information, as the performance of Mandarin L2 learners of English indicates. Our findings provide further support for a cognitive transfer between the language and music domain. PMID:27375469

  18. The Enhanced Musical Rhythmic Perception in Second Language Learners.

    PubMed

    Roncaglia-Denissen, M Paula; Roor, Drikus A; Chen, Ao; Sadakata, Makiko

    2016-01-01

    Previous research suggests that mastering languages with distinct rather than similar rhythmic properties enhances musical rhythmic perception. This study investigates whether learning a second language (L2) contributes to enhanced musical rhythmic perception in general, regardless of first and second languages rhythmic properties. Additionally, we investigated whether this perceptual enhancement could be alternatively explained by exposure to musical rhythmic complexity, such as the use of compound meter in Turkish music. Finally, it investigates if an enhancement of musical rhythmic perception could be observed among L2 learners whose first language relies heavily on pitch information, as is the case with tonal languages. Therefore, we tested Turkish, Dutch and Mandarin L2 learners of English and Turkish monolinguals on their musical rhythmic perception. Participants' phonological and working memory capacities, melodic aptitude, years of formal musical training and daily exposure to music were assessed to account for cultural and individual differences which could impact their rhythmic ability. Our results suggest that mastering a L2 rather than exposure to musical rhythmic complexity could explain individuals' enhanced musical rhythmic perception. An even stronger enhancement of musical rhythmic perception was observed for L2 learners whose first and second languages differ regarding their rhythmic properties, as enhanced performance of Turkish in comparison with Dutch L2 learners of English seem to suggest. Such a stronger enhancement of rhythmic perception seems to be found even among L2 learners whose first language relies heavily on pitch information, as the performance of Mandarin L2 learners of English indicates. Our findings provide further support for a cognitive transfer between the language and music domain.

  19. 24-hour rhythmicity of seizures in refractory focal epilepsy.

    PubMed

    Nzwalo, Hipólito; Menezes Cordeiro, Inês; Santos, Ana Catarina; Peralta, Rita; Paiva, Teresa; Bentes, Carla

    2016-02-01

    The occurrence of seizures in specific types of epilepsies can follow a 24-hour nonuniform or nonrandom pattern. We described the 24-hour pattern of clinical seizures in patients with focal refractory epilepsy who underwent video-electroencephalography monitoring. Only patients who were candidates for epilepsy surgery with an unequivocal seizure focus were included in the study. A total of 544 seizures from 123 consecutive patients were analyzed. Specific time of seizures were distributed along 3- or 4-hour time blocks or bins throughout the 24-hour period. The mean age of the subjects was 37.7 years, with standard deviation of 11.5 years, median of 37. The majority were females (70/56%). The majority of patients had a seizure focus located in the mesial temporal lobe (102/83%) and in the neocortical temporal lobe (13/11%). The remaining patients had a seizure focus located in the extratemporal lobe (8/6%). The most common etiology was mesial temporal sclerosis (86/69.9%). Nonuniform seizure distribution was observed in seizures arising from the temporal lobe (mesial temporal lobe and neocortical temporal lobe), with two peaks found in both 3- and 4-hour bins: 10:00-13:00/16:00-19:00 and 08:00-12:00/16:00-20:00 respectively (p=0.004). No specific 24-hour pattern was identified in seizures from extratemporal location. The 24-hour rhythmicity of seizure distribution is recognized in certain types of epilepsy, but studies on the topic are scarce. Their replication and validation is therefore needed. Our study confirms the bimodal pattern of temporal lobe epilepsy independently of the nature of the lesion. However, peak times differ between different studies, suggesting that the ambient, rhythmic exogenous factors or environmental/social zeitgebers, may modulate the 24-hour rhythmicity of seizures. Characterization of these 24-hour patterns of seizure occurrence can influence diagnosis and treatment in selected types of epilepsy, such as the case of temporal lobe

  20. A review of stereotactic body radiotherapy – is volumetric modulated arc therapy the answer?

    SciTech Connect

    Sapkaroski, Daniel Osborne, Catherine; Knight, Kellie A

    2015-06-15

    Stereotactic body radiotherapy (SBRT) is a high precision radiotherapy technique used for the treatment of small to moderate extra-cranial tumours. Early studies utilising SBRT have shown favourable outcomes. However, major disadvantages of static field SBRT include long treatment times and toxicity complications. Volumetric modulated arc therapy (VMAT) and intensity modulated radiotherapy (IMRT) may potentially mitigate these disadvantages. This review aims to assess the feasibility of emerging VMAT and IMRT-based SBRT treatment techniques and qualify which offers the best outcome for patients, whilst identifying any emerging and advantageous SBRT planning trends. A review and synthesis of data from current literature up to September 2013 was conducted on EMBASE, Medline, PubMed, Science Direct, Proquest central, Google Scholar and the Cochrane Database of Systematic reviews. Only full text papers comparing VMAT and or IMRT and or Static SBRT were included. Ten papers were identified that evaluated the results of VMAT/IMRT SBRT. Five related to medically inoperable stage 1 and 2 non-small-cell lung cancer (NSCLC), three to spinal metastasis, one related to abdominal lymph node malignancies, with the final one looking at pancreatic adenocarcinoma. Overall treatment times with VMAT were reduced by 66–70% for lung, 46–58% for spine, 42% and 21% for lymph node and pancreatic metastasis respectively, planning constraints were met with several studies showing improved organs at risk sparing with IMRT/VMAT to static SBRT. Both IMRT and VMAT were able to meet all planning constraints in the studies reviewed, with VMAT offering the greatest treatment efficiency. Early clinical outcomes with VMAT and IMRT SBRT have demonstrated excellent local control and favourable survival outcomes.

  1. Volumetric-modulated arc therapy using multicriteria optimization for body and extremity sarcoma.

    PubMed

    Young, Michael R; Craft, David L; Colbert, Caroline M; Remillard, Kyla; Vanbenthuysen, Liam; Wang, Yi

    2016-11-08

    This study evaluates the implementation of volumetric-modulated arc therapy (VMAT) using multicriteria optimization (MCO) in the RayStation treatment planning system (TPS) for complex sites, namely extremity and body sarcoma. The VMAT-MCO algorithm implemented in RayStation is newly developed and requires an integrated, comprehensive analysis of plan generation, delivery, and treatment efficiency. Ten patients previously treated by intensity-modulated radiation therapy (IMRT) with MCO were randomly selected and replanned using VMAT-MCO. The plan quality was compared using homogeneity index (HI) and conformity index (CI) of the planning target volume (PTV) and dose sparing of organs at risk (OARs). Given the diversity of the tumor location, the 10 plans did not have a common OAR except for skin. The skin D50 and Dmean was directly compared between VMAT-MCO and IMRT-MCO. Additional OAR dose points were compared on a plan-by-plan basis. The treatment efficiency was compared using plan monitor units (MU) and net beam-on time. Plan quality assurance was performed using the Sun Nuclear ArcCHECK phantom and a gamma criteria of 3%/3 mm. No statistically significant differences were found between VMAT- and IMRT-MCO for HI and CI of the PTV or D50 and Dmean to the skin. The VMAT-MCO plans showed general improvements in sparing to OARs. The VMAT-MCO plan set showed statistically significant improvements over the IMRT-MCO set in treatment efficiency per plan MU (p < 0.05) and net beam-on time (p < 0.01). The VMAT-MCO plan deliverability was validated. Similar gamma passing rates were observed for the two modalities. This study verifies the suitability of VMAT-MCO for sarcoma cancer and highlighted the comparability in plan quality and improve-ment in treatment efficiency offered by VMAT-MCO as compared to IMRT-MCO.

  2. Human cervical spinal cord circuitry activated by tonic input can generate rhythmic arm movements.

    PubMed

    Solopova, I A; Selionov, V A; Zhvansky, D S; Gurfinkel, V S; Ivanenko, Y

    2016-02-01

    The coordination between arms and legs during human locomotion shares many features with that in quadrupeds, yet there is limited evidence for the central pattern generator for the upper limbs in humans. Here we investigated whether different types of tonic stimulation, previously used for eliciting stepping-like leg movements, may evoke nonvoluntary rhythmic arm movements. Twenty healthy subjects participated in this study. The subject was lying on the side, the trunk was fixed, and all four limbs were suspended in a gravity neutral position, allowing unrestricted low-friction limb movements in the horizontal plane. The results showed that peripheral sensory stimulation (continuous muscle vibration) and central tonic activation (postcontraction state of neuronal networks following a long-lasting isometric voluntary effort, Kohnstamm phenomenon) could evoke nonvoluntary rhythmic arm movements in most subjects. In ∼40% of subjects, tonic stimulation elicited nonvoluntary rhythmic arm movements together with rhythmic movements of suspended legs. The fact that not all participants exhibited nonvoluntary limb oscillations may reflect interindividual differences in responsiveness of spinal pattern generation circuitry to its activation. The occurrence and the characteristics of induced movements highlight the rhythmogenesis capacity of cervical neuronal circuitries, complementing the growing body of work on the quadrupedal nature of human gait.

  3. Rhythmic complexity and predictive coding: a novel approach to modeling rhythm and meter perception in music.

    PubMed

    Vuust, Peter; Witek, Maria A G

    2014-01-01

    Musical rhythm, consisting of apparently abstract intervals of accented temporal events, has a remarkable capacity to move our minds and bodies. How does the cognitive system enable our experiences of rhythmically complex music? In this paper, we describe some common forms of rhythmic complexity in music and propose the theory of predictive coding (PC) as a framework for understanding how rhythm and rhythmic complexity are processed in the brain. We also consider why we feel so compelled by rhythmic tension in music. First, we consider theories of rhythm and meter perception, which provide hierarchical and computational approaches to modeling. Second, we present the theory of PC, which posits a hierarchical organization of brain responses reflecting fundamental, survival-related mechanisms associated with predicting future events. According to this theory, perception and learning is manifested through the brain's Bayesian minimization of the error between the input to the brain and the brain's prior expectations. Third, we develop a PC model of musical rhythm, in which rhythm perception is conceptualized as an interaction between what is heard ("rhythm") and the brain's anticipatory structuring of music ("meter"). Finally, we review empirical studies of the neural and behavioral effects of syncopation, polyrhythm and groove, and propose how these studies can be seen as special cases of the PC theory. We argue that musical rhythm exploits the brain's general principles of prediction and propose that pleasure and desire for sensorimotor synchronization from musical rhythm may be a result of such mechanisms.

  4. Dietary protein modulates circadian changes in core body temperature and metabolic rate in rats.

    PubMed

    Yamaoka, Ippei; Nakayama, Mitsuo; Miki, Takanori; Yokoyama, Toshifumi; Takeuchi, Yoshiki

    2008-02-01

    We assessed the contribution of dietary protein to circadian changes in core body temperature (Tb) and metabolic rate in freely moving rats. Daily changes in rat intraperitoneal temperature, locomotor activity (LMA), whole-body oxygen consumption (VO2), and carbon dioxide production (VCO2) were measured before and during 4 days of consuming a 20% protein diet (20% P), a protein-free diet (0% P), or a pair-fed 20% P diet (20% P-R). Changes in Tb did not significantly differ between the 20% P and 20% P-R groups throughout the study. The Tb in the 0% P group remained elevated during the dark (D) phase throughout the study, but VO2, VCO2, and LMA increased late in the study when compared with the 20% P-R group almost in accordance with elevated Tb. By contrast, during the light (L) phase in the 0% P group, Tb became elevated early in the study and thereafter declined with a tendency to accompany significantly lower VO2 and VCO2 when compared with the 20% P group, but not the 20% P-R group. The respiratory quotient (RQ) in the 0% P group declined throughout the D phase and during the early L phase. By contrast, RQ in the 20% P-R group consistently decreased from the late D phase to the end of the L phase. Our findings suggest that dietary protein contributes to the maintenance of daily oscillations in Tb with modulating metabolic rates during the D phase. However, the underlying mechanisms of Tb control during the L phase remain obscure.

  5. Modulation of Stress Granules and P Bodies during Dicistrovirus Infection ▿

    PubMed Central

    Khong, Anthony; Jan, Eric

    2011-01-01

    Stress granules (SGs) are dynamic cytosolic aggregates composed of ribonucleoproteins that are induced during cellular stress when protein synthesis is inhibited. The function of SGs is poorly understood, but they are thought to be sites for reorganizing mRNA and protein. Several viruses can modulate SG formation, suggesting that SGs have an impact on virus infection. In this study, we have investigated the relationship of SG formation in Drosophila S2 cells infected by cricket paralysis virus (CrPV), a member of the Dicistroviridae family. Despite a rapid shutoff of host translation during CrPV infection, several hallmark SG markers such as the Drosophila TIA-1 and G3BP (RasGAP-SH3-binding protein) homologs, Rox8 and Rin, respectively, do not aggregate in CrPV-infected cells, even when challenged with potent SG inducers such as heat shock, oxidative stress, and pateamine A treatment. Furthermore, we demonstrate that a subset of P body markers become moderately dispersed at late times of infection. In contrast, as shown by fluorescent in situ hybridization, poly(A)+ RNA granules still form at late times of infection. These poly(A)+ RNA granules do not contain viral RNA nor do they colocalize with P body markers. Finally, our results demonstrate that the CrPV viral 3C protease is sequestered to SGs under cellular stress but not during virus infection. In summary, we propose that dicistrovirus infection leads to the selective inhibition of distinct SGs so that viral proteins are available for viral processing. PMID:21106737

  6. Order restricted inference for oscillatory systems for detecting rhythmic signals

    PubMed Central

    Larriba, Yolanda; Rueda, Cristina; Fernández, Miguel A.; Peddada, Shyamal D.

    2016-01-01

    Motivation: Many biological processes, such as cell cycle, circadian clock, menstrual cycles, are governed by oscillatory systems consisting of numerous components that exhibit rhythmic patterns over time. It is not always easy to identify such rhythmic components. For example, it is a challenging problem to identify circadian genes in a given tissue using time-course gene expression data. There is a great potential for misclassifying non-rhythmic as rhythmic genes and vice versa. This has been a problem of considerable interest in recent years. In this article we develop a constrained inference based methodology called Order Restricted Inference for Oscillatory Systems (ORIOS) to detect rhythmic signals. Instead of using mathematical functions (e.g. sinusoidal) to describe shape of rhythmic signals, ORIOS uses mathematical inequalities. Consequently, it is robust and not limited by the biologist's choice of the mathematical model. We studied the performance of ORIOS using simulated as well as real data obtained from mouse liver, pituitary gland and data from NIH3T3, U2OS cell lines. Our results suggest that, for a broad collection of patterns of gene expression, ORIOS has substantially higher power to detect true rhythmic genes in comparison to some popular methods, while also declaring substantially fewer non-rhythmic genes as rhythmic. Availability and Implementation: A user friendly code implemented in R language can be downloaded from http://www.niehs.nih.gov/research/atniehs/labs/bb/staff/peddada/index.cfm. Contact: peddada@niehs.nih.gov PMID:27596593

  7. Linac-based total body irradiation (TBI) with volumetric modulated arc therapy (VMAT)

    NASA Astrophysics Data System (ADS)

    Tas, B.; Durmus, I. F.; Okumus, A.; Uzel, O. E.

    2017-02-01

    To evaluate dose distribution of Volumetric modulated arc therapy (VMAT) planning tecnique using Versa HD® lineer accelerator to deliver Total Body Irradiation (TBI) on the coach. Eight TBI patient's Treatment Planning System (TPS) were performed with dual arc VMAT for each patient. The VMAT-TBI consisted of three isocentres and three dual overlapping arcs. The prescribed dose was 12 Gy. Mean dose to lung and kidney were restricted less than 10 Gy and max. dose to lens were restricted less than 6 Gy. The plans were verified using 2D array and ion chamber. The comparison between calculation and measurement were made by γ-index analysis and absolute dose. An average total delivery time was determined 923±34 seconds and an average MU was determined 2614±228 MUs for dual arc VMAT. Mean dose to lungs was 9.7±0.2 Gy, mean dose to kidneys was 8.8±0.3 Gy, max. dose to lens was 5.5±0.3 Gy and max. dose was 14.6±0.3 Gy, HI of PTV was 1.13±0.2, mean dose to PTV was 12.6±1.5 Gy and mean γ-index pass rate was %97.1±1.9. The results show that the tecnique for TBI using VMAT on the treatment coach is feasible.

  8. Novel modulators for body weight changes induced by fasting and re-feeding in mice.

    PubMed

    Nonogaki, Katsunori; Ohba, Yukie; Sumii, Makiko; Wakameda, Mamoru; Tamari, Tomohiro

    2009-01-09

    Catch-up weight gain after malnutrition is a risk factor for metabolic syndrome. Here we show that social isolation enhanced fasting-induced weight loss and suppressed weight gain induced by re-feeding for 6 days following a 24-h fast in prepubertal wild-type mice. These effects of social isolation on weight gain were not associated with significant changes in daily average food consumption. Under the same housing condition, genetic deletion of beta-endorphin reduced the fasting-induced weight loss and enhanced the re-feeding-induced weight gain in prepubertal mice. These effects of social isolation or genetic deletion of beta-endorphin on these weight changes were attenuated and reversed in postpubertal mice. Moreover, genetic deletion of beta-endorphin attenuated these effects of social isolation on the catch-up weight gain in prepubertal mice and reversed them in postpubertal mice. Thus, social isolation, endogenous beta-endorphin, and age can be novel modulators for body weight changes induced by fasting and re-feeding in mice.

  9. Engineering a Blood Vessel Network Module for Body-on-a-Chip Applications.

    PubMed

    Ryu, Hyunryul; Oh, Soojung; Lee, Hyun Jae; Lee, Jin Young; Lee, Hae Kwang; Jeon, Noo Li

    2015-06-01

    The blood circulatory system links all organs from one to another to support and maintain each organ's functions consistently. Therefore, blood vessels have been considered as a vital unit. Engineering perfusable functional blood vessels in vitro has been challenging due to difficulties in designing the connection between rigid macroscale tubes and fragile microscale ones. Here, we propose a generalizable method to engineer a "long" perfusable blood vessel network. To form millimeter-scale vessels, fibroblasts were co-cultured with human umbilical vein endothelial cells (HUVECs) in close proximity. In contrast to previous works, in which all cells were permanently placed within the device, we developed a novel method to culture paracrine factor secreting fibroblasts on an O-ring-shaped guide that can be transferred in and out. This approach affords flexibility in co-culture, where the effects of secreted factors can be decoupled. Using this, blood vessels with length up to 2 mm were successfully produced in a reproducible manner (>90%). Because the vessels form a perfusable network within the channel, simple links to inlets and outlets of the device allowed connections to the outside world. The robust and reproducible formation of in vitro engineered vessels can be used as a module to link various organ components as parts of future body-on-a-chip applications.

  10. Sfr1, a Tetrahymena thermophila Sfi1 Repeat Protein, Modulates the Production of Cortical Row Basal Bodies

    PubMed Central

    Heydeck, Westley; Stemm-Wolf, Alexander J.; Knop, Janin; Poh, Christina C.

    2016-01-01

    ABSTRACT Basal bodies are essential microtubule-based structures that template, anchor, and orient cilia at the cell surface. Cilia act primarily in the generation of directional fluid flow and sensory reception, both of which are utilized for a broad spectrum of cellular processes. Although basal bodies contribute to vital cell functions, the molecular contributors of their assembly and maintenance are poorly understood. Previous studies of the ciliate Tetrahymena thermophila revealed important roles for two centrin family members in basal body assembly, separation of new basal bodies, and stability. Here, we characterize the basal body function of a centrin-binding protein, Sfr1, in Tetrahymena. Sfr1 is part of a large family of 13 proteins in Tetrahymena that contain Sfi1 repeats (SFRs), a motif originally identified in Saccharomyces cerevisiae Sfi1 that binds centrin. Sfr1 is the only SFR protein in Tetrahymena that localizes to all cortical row and oral apparatus basal bodies. In addition, Sfr1 resides predominantly at the microtubule scaffold from the proximal cartwheel to the distal transition zone. Complete genomic knockout of SFR1 (sfr1Δ) causes a significant increase in both cortical row basal body density and the number of cortical rows, contributing to an overall overproduction of basal bodies. Reintroduction of Sfr1 into sfr1Δ mutant cells leads to a marked reduction of cortical row basal body density and the total number of cortical row basal bodies. Therefore, Sfr1 directly modulates cortical row basal body production. This study reveals an inhibitory role for Sfr1, and potentially centrins, in Tetrahymena basal body production. IMPORTANCE Basal bodies and centrioles are structurally similar and, when rendered dysfunctional as a result of improper assembly or maintenance, are associated with human diseases. Centrins are conserved and abundant components of both structures whose basal body and centriolar functions remain incompletely understood

  11. Rhythmicity, Recurrence, and Recovery of Flagellar Beating

    NASA Astrophysics Data System (ADS)

    Wan, Kirsty Y.; Goldstein, Raymond E.

    2014-12-01

    The eukaryotic flagellum beats with apparently unfailing periodicity, yet responds rapidly to stimuli. Like the human heartbeat, flagellar oscillations are now known to be noisy. Using the alga C. reinhardtii, we explore three aspects of nonuniform flagellar beating. We report the existence of rhythmicity, waveform noise peaking at transitions between power and recovery strokes, and fluctuations of interbeat intervals that are correlated and even recurrent, with memory extending to hundreds of beats. These features are altered qualitatively by physiological perturbations. Further, we quantify the recovery of periodic breaststroke beating from transient hydrodynamic forcing. These results will help constrain microscopic theories on the origins and regulation of flagellar beating.

  12. My Body Looks Like That Girl's: Body Mass Index Modulates Brain Activity during Body Image Self-Reflection among Young Women.

    PubMed

    Gao, Xiao; Deng, Xiao; Wen, Xin; She, Ying; Vinke, Petra Corianne; Chen, Hong

    2016-01-01

    Body image distress or body dissatisfaction is one of the most common consequences of obesity and overweight. We investigated the neural bases of body image processing in overweight and average weight young women to understand whether brain regions that were previously found to be involved in processing self-reflective, perspective and affective components of body image would show different activation between two groups. Thirteen overweight (O-W group, age = 20.31±1.70 years) and thirteen average weight (A-W group, age = 20.15±1.62 years) young women underwent functional magnetic resonance imaging while performing a body image self-reflection task. Among both groups, whole-brain analysis revealed activations of a brain network related to perceptive and affective components of body image processing. ROI analysis showed a main effect of group in ACC as well as a group by condition interaction within bilateral EBA, bilateral FBA, right IPL, bilateral DLPFC, left amygdala and left MPFC. For the A-W group, simple effect analysis revealed stronger activations in Thin-Control compared to Fat-Control condition within regions related to perceptive (including bilateral EBA, bilateral FBA, right IPL) and affective components of body image processing (including bilateral DLPFC, left amygdala), as well as self-reference (left MPFC). The O-W group only showed stronger activations in Fat-Control than in Thin-Control condition within regions related to the perceptive component of body image processing (including left EBA and left FBA). Path analysis showed that in the Fat-Thin contrast, body dissatisfaction completely mediated the group difference in brain response in left amygdala across the whole sample. Our data are the first to demonstrate differences in brain response to body pictures between average weight and overweight young females involved in a body image self-reflection task. These results provide insights for understanding the vulnerability to body image distress

  13. My Body Looks Like That Girl’s: Body Mass Index Modulates Brain Activity during Body Image Self-Reflection among Young Women

    PubMed Central

    Wen, Xin; She, Ying; Vinke, Petra Corianne; Chen, Hong

    2016-01-01

    Body image distress or body dissatisfaction is one of the most common consequences of obesity and overweight. We investigated the neural bases of body image processing in overweight and average weight young women to understand whether brain regions that were previously found to be involved in processing self-reflective, perspective and affective components of body image would show different activation between two groups. Thirteen overweight (O-W group, age = 20.31±1.70 years) and thirteen average weight (A-W group, age = 20.15±1.62 years) young women underwent functional magnetic resonance imaging while performing a body image self-reflection task. Among both groups, whole-brain analysis revealed activations of a brain network related to perceptive and affective components of body image processing. ROI analysis showed a main effect of group in ACC as well as a group by condition interaction within bilateral EBA, bilateral FBA, right IPL, bilateral DLPFC, left amygdala and left MPFC. For the A-W group, simple effect analysis revealed stronger activations in Thin-Control compared to Fat-Control condition within regions related to perceptive (including bilateral EBA, bilateral FBA, right IPL) and affective components of body image processing (including bilateral DLPFC, left amygdala), as well as self-reference (left MPFC). The O-W group only showed stronger activations in Fat-Control than in Thin-Control condition within regions related to the perceptive component of body image processing (including left EBA and left FBA). Path analysis showed that in the Fat-Thin contrast, body dissatisfaction completely mediated the group difference in brain response in left amygdala across the whole sample. Our data are the first to demonstrate differences in brain response to body pictures between average weight and overweight young females involved in a body image self-reflection task. These results provide insights for understanding the vulnerability to body image distress

  14. Fibroblast PER2 Circadian Rhythmicity Depends on Cell Density

    PubMed Central

    Noguchi, Takako; Wang, Lexie L.; Welsh, David K.

    2013-01-01

    Like neurons in the suprachiasmatic nucleus (SCN), the master circadian pacemaker in the brain, single fibroblasts can function as independent oscillators. In the SCN, synaptic and paracrine signaling among cells creates a robust, synchronized circadian oscillation, whereas there is no evidence for such integration in fibroblast cultures. However, interactions among single-cell fibroblast oscillators cannot be completely excluded, because fibroblasts were not isolated in previous work. In this study, we tested the autonomy of fibroblasts as single-cell circadian oscillators in high and low density culture, by single-cell imaging of cells from PER2::LUC circadian reporter mice. We found greatly reduced PER2::LUC rhythmicity in low density cultures, which could result from lack of either constitutive or rhythmic paracrine signals from neighboring fibroblasts. To discriminate between these two possibilities, we mixed PER2::LUC wild type (WT) cells with non-luminescent, non-rhythmic Bmal1−/− cells, so that density of rhythmic cells was low but overall cell density remained high. In this condition, WT cells showed clear rhythmicity similar to high density cultures. We also mixed PER2::LUC WT cells with non-luminescent, long period Cry2−/− cells. In this condition, WT cells showed a period no different from cells cultured with rhythmic WT cells or non-rhythmic Bmal1−/− cells. In previous work, we found that low K+ suppresses fibroblast rhythmicity, and we and others have found that either low K+ or low Ca2+ suppresses SCN rhythmicity. Therefore, we attempted to rescue rhythmicity of low density fibroblasts with high K+ (21 mM), high Ca2+ (3.6 mM), or conditioned medium. Conditioned medium from high density fibroblast cultures rescued rhythmicity of low density cultures, whereas high K+ or Ca2+ medium did not consistently rescue rhythmicity. These data suggest that fibroblasts require paracrine signals from adjacent cells for normal expression of rhythmicity

  15. Volumetric-modulated arc therapy using multicriteria optimization for body and extremity sarcoma.

    PubMed

    Young, Michael R; Craft, David L; Colbert, Caroline M; Remillard, Kyla; Vanbenthuysen, Liam; Wang, Yi

    2016-11-01

    This study evaluates the implementation of volumetric-modulated arc therapy (VMAT) using multicriteria optimization (MCO) in the RayStation treatment planning system (TPS) for complex sites, namely extremity and body sarcoma. The VMAT-MCO algorithm implemented in RayStation is newly developed and requires an integrated, comprehensive analysis of plan generation, delivery, and treatment efficiency. Ten patients previously treated by intensity-modulated radiation therapy (IMRT) with MCO were randomly selected and replanned using VMAT-MCO. The plan quality was compared using homogeneity index (HI) and conformity index (CI) of the planning target volume (PTV) and dose sparing of organs at risk (OARs). Given the diversity of the tumor location, the 10 plans did not have a common OAR except for skin. The skin D50 and Dmean was directly compared between VMAT-MCO and IMRT-MCO. Additional OAR dose points were compared on a plan-by-plan basis. The treatment efficiency was compared using plan monitor units (MU) and net beam-on time. Plan quality assurance was performed using the Sun Nuclear ArcCHECK phantom and a gamma criteria of 3%/3 mm. No statistically significant differences were found between VMAT- and IMRT-MCO for HI and CI of the PTV or D50 and Dmean to the skin. The VMAT-MCO plans showed general improvements in sparing to OARs. The VMAT-MCO plan set showed statistically significant improvements over the IMRT-MCO set in treatment efficiency per plan MU (p<0.05) and net beam-on time (p<0.01). The VMAT-MCO plan deliverability was validated. Similar gamma passing rates were observed for the two modalities. This study verifies the suitability of VMAT-MCO for sarcoma cancer and highlighted the comparability in plan quality and improvement in treatment efficiency offered by VMAT-MCO as compared to IMRT-MCO. PACS number(s): separated by commas 87.55.D, 87.55.de, 87.55.Qr.

  16. A rhythmic modulatory gating system in the stomatogastric nervous system of Homarus gammarus. III. Rhythmic control of the pyloric CPG.

    PubMed

    Cardi, P; Nagy, F

    1994-06-01

    1. Two modulatory neurons, P and commissural pyloric (CP), known to be involved in the long-term maintenance of pyloric central pattern generator operation in the rock lobster Homarus gammarus, are members of the commissural pyloric oscillator (CPO), a higher-order oscillator influencing the pyloric network. 2. The CP neuron was endogenously oscillating in approximately 30% of the preparations in which its cell body was impaled. Rhythmic inhibitory feedback from the pyloric pacemaker anterior burster (AB) neuron stabilized the CP neuron's endogenous rhythm. 3. The organization of the CPO is described. Follower commissural neurons, the F cells, and the CP neuron receive a common excitatory postsynaptic potential from another commissural neuron, the large exciter (LE). When in oscillatory state, CP in turn excites the LE neuron. This positive feedback may maintain long episodes of CP oscillations. 4. The pyloric pacemaker neurons follow the CPO rhythm with variable coordination modes (i.e., 1:1, 1:2) and switch among these modes when their membrane potential is modified. The CPO inputs strongly constrain the pyloric period, which as a result may adopt only a few discrete values. This effect is based on mechanisms of entrainment between the CPO and the pyloric oscillator. 5. Pyloric constrictor neurons show differential sensitivity from the pyloric pacemaker neurons with respect to the CPO inputs. Consequently, their bursting period can be a shorter harmonic of the bursting period of the pyloric pacemakers neurons. 6. The CPO neurons seem to be the first example of modulatory gating neurons that also give timing cues to a rhythmic pattern generating network.

  17. Spike integration and cellular memory in a rhythmic network from Na+/K+ pump current dynamics

    PubMed Central

    Pulver, Stefan R.

    2009-01-01

    The output of a neural circuit results from an interaction between the intrinsic properties of neurons within the circuit and the features of the synaptic connections between them. The plasticity of intrinsic properties has been primarily attributed to modification of ion channel function and/or number. In this study, we demonstrate a mechanism for intrinsic plasticity in rhythmically active Drosophila neurons that is not conductance-based. Larval motor neurons show a long lasting sodium-dependent afterhyperpolarization (AHP) following bursts of action potentials that is mediated by the electrogenic activity of Na+/K+ ATPase. This AHP persists for multiple seconds following volleys of action potentials and is able to function as a pattern-insensitive integrator of spike number that is independent of external calcium. This current also interacts with endogenous Shal K+ conductances to modulate spike timing for multiple seconds following rhythmic activity, providing a cellular memory of network activity on a behaviorally relevant time scale. PMID:19966842

  18. Modulation of genetic associations with serum urate levels by body-mass-index in humans.

    PubMed

    Huffman, Jennifer E; Albrecht, Eva; Teumer, Alexander; Mangino, Massimo; Kapur, Karen; Johnson, Toby; Kutalik, Zoltán; Pirastu, Nicola; Pistis, Giorgio; Lopez, Lorna M; Haller, Toomas; Salo, Perttu; Goel, Anuj; Li, Man; Tanaka, Toshiko; Dehghan, Abbas; Ruggiero, Daniela; Malerba, Giovanni; Smith, Albert V; Nolte, Ilja M; Portas, Laura; Phipps-Green, Amanda; Boteva, Lora; Navarro, Pau; Johansson, Asa; Hicks, Andrew A; Polasek, Ozren; Esko, Tõnu; Peden, John F; Harris, Sarah E; Murgia, Federico; Wild, Sarah H; Tenesa, Albert; Tin, Adrienne; Mihailov, Evelin; Grotevendt, Anne; Gislason, Gauti K; Coresh, Josef; D'Adamo, Pio; Ulivi, Sheila; Vollenweider, Peter; Waeber, Gerard; Campbell, Susan; Kolcic, Ivana; Fisher, Krista; Viigimaa, Margus; Metter, Jeffrey E; Masciullo, Corrado; Trabetti, Elisabetta; Bombieri, Cristina; Sorice, Rossella; Döring, Angela; Reischl, Eva; Strauch, Konstantin; Hofman, Albert; Uitterlinden, Andre G; Waldenberger, Melanie; Wichmann, H-Erich; Davies, Gail; Gow, Alan J; Dalbeth, Nicola; Stamp, Lisa; Smit, Johannes H; Kirin, Mirna; Nagaraja, Ramaiah; Nauck, Matthias; Schurmann, Claudia; Budde, Kathrin; Farrington, Susan M; Theodoratou, Evropi; Jula, Antti; Salomaa, Veikko; Sala, Cinzia; Hengstenberg, Christian; Burnier, Michel; Mägi, Reedik; Klopp, Norman; Kloiber, Stefan; Schipf, Sabine; Ripatti, Samuli; Cabras, Stefano; Soranzo, Nicole; Homuth, Georg; Nutile, Teresa; Munroe, Patricia B; Hastie, Nicholas; Campbell, Harry; Rudan, Igor; Cabrera, Claudia; Haley, Chris; Franco, Oscar H; Merriman, Tony R; Gudnason, Vilmundur; Pirastu, Mario; Penninx, Brenda W; Snieder, Harold; Metspalu, Andres; Ciullo, Marina; Pramstaller, Peter P; van Duijn, Cornelia M; Ferrucci, Luigi; Gambaro, Giovanni; Deary, Ian J; Dunlop, Malcolm G; Wilson, James F; Gasparini, Paolo; Gyllensten, Ulf; Spector, Tim D; Wright, Alan F; Hayward, Caroline; Watkins, Hugh; Perola, Markus; Bochud, Murielle; Kao, W H Linda; Caulfield, Mark; Toniolo, Daniela; Völzke, Henry; Gieger, Christian; Köttgen, Anna; Vitart, Veronique

    2015-01-01

    We tested for interactions between body mass index (BMI) and common genetic variants affecting serum urate levels, genome-wide, in up to 42569 participants. Both stratified genome-wide association (GWAS) analyses, in lean, overweight and obese individuals, and regression-type analyses in a non BMI-stratified overall sample were performed. The former did not uncover any novel locus with a major main effect, but supported modulation of effects for some known and potentially new urate loci. The latter highlighted a SNP at RBFOX3 reaching genome-wide significant level (effect size 0.014, 95% CI 0.008-0.02, Pinter= 2.6 x 10-8). Two top loci in interaction term analyses, RBFOX3 and ERO1LB-EDARADD, also displayed suggestive differences in main effect size between the lean and obese strata. All top ranking loci for urate effect differences between BMI categories were novel and most had small magnitude but opposite direction effects between strata. They include the locus RBMS1-TANK (men, Pdifflean-overweight= 4.7 x 10-8), a region that has been associated with several obesity related traits, and TSPYL5 (men, Pdifflean-overweight= 9.1 x 10-8), regulating adipocytes-produced estradiol. The top-ranking known urate loci was ABCG2, the strongest known gout risk locus, with an effect halved in obese compared to lean men (Pdifflean-obese= 2 x 10-4). Finally, pathway analysis suggested a role for N-glycan biosynthesis as a prominent urate-associated pathway in the lean stratum. These results illustrate a potentially powerful way to monitor changes occurring in obesogenic environment.

  19. Modulation of Genetic Associations with Serum Urate Levels by Body-Mass-Index in Humans

    PubMed Central

    Huffman, Jennifer E.; Albrecht, Eva; Teumer, Alexander; Mangino, Massimo; Kapur, Karen; Johnson, Toby; Kutalik, Zoltán; Pirastu, Nicola; Pistis, Giorgio; Lopez, Lorna M.; Haller, Toomas; Salo, Perttu; Goel, Anuj; Li, Man; Tanaka, Toshiko; Dehghan, Abbas; Ruggiero, Daniela; Malerba, Giovanni; Smith, Albert V.; Nolte, Ilja M.; Portas, Laura; Phipps-Green, Amanda; Boteva, Lora; Navarro, Pau; Johansson, Asa; Hicks, Andrew A.; Polasek, Ozren; Esko, Tõnu; Peden, John F.; Harris, Sarah E.; Murgia, Federico; Wild, Sarah H.; Tenesa, Albert; Tin, Adrienne; Mihailov, Evelin; Grotevendt, Anne; Gislason, Gauti K.; Coresh, Josef; D'Adamo, Pio; Ulivi, Sheila; Vollenweider, Peter; Waeber, Gerard; Campbell, Susan; Kolcic, Ivana; Fisher, Krista; Viigimaa, Margus; Metter, Jeffrey E.; Masciullo, Corrado; Trabetti, Elisabetta; Bombieri, Cristina; Sorice, Rossella; Döring, Angela; Reischl, Eva; Strauch, Konstantin; Hofman, Albert; Uitterlinden, Andre G.; Waldenberger, Melanie; Wichmann, H-Erich; Davies, Gail; Gow, Alan J.; Dalbeth, Nicola; Stamp, Lisa; Smit, Johannes H.; Kirin, Mirna; Nagaraja, Ramaiah; Nauck, Matthias; Schurmann, Claudia; Budde, Kathrin; Farrington, Susan M.; Theodoratou, Evropi; Jula, Antti; Salomaa, Veikko; Sala, Cinzia; Hengstenberg, Christian; Burnier, Michel; Mägi, Reedik; Klopp, Norman; Kloiber, Stefan; Schipf, Sabine; Ripatti, Samuli; Cabras, Stefano; Soranzo, Nicole; Homuth, Georg; Nutile, Teresa; Munroe, Patricia B.; Hastie, Nicholas; Campbell, Harry; Rudan, Igor; Cabrera, Claudia; Haley, Chris; Franco, Oscar H.; Merriman, Tony R.; Gudnason, Vilmundur; Pirastu, Mario; Penninx, Brenda W.; Snieder, Harold; Metspalu, Andres; Ciullo, Marina; Pramstaller, Peter P.; van Duijn, Cornelia M.; Ferrucci, Luigi; Gambaro, Giovanni; Deary, Ian J.; Dunlop, Malcolm G.; Wilson, James F.; Gasparini, Paolo; Gyllensten, Ulf; Spector, Tim D.; Wright, Alan F.; Hayward, Caroline; Watkins, Hugh; Perola, Markus; Bochud, Murielle; Kao, W. H. Linda; Caulfield, Mark; Toniolo, Daniela; Völzke, Henry; Gieger, Christian; Köttgen, Anna; Vitart, Veronique

    2015-01-01

    We tested for interactions between body mass index (BMI) and common genetic variants affecting serum urate levels, genome-wide, in up to 42569 participants. Both stratified genome-wide association (GWAS) analyses, in lean, overweight and obese individuals, and regression-type analyses in a non BMI-stratified overall sample were performed. The former did not uncover any novel locus with a major main effect, but supported modulation of effects for some known and potentially new urate loci. The latter highlighted a SNP at RBFOX3 reaching genome-wide significant level (effect size 0.014, 95% CI 0.008-0.02, Pinter= 2.6 x 10-8). Two top loci in interaction term analyses, RBFOX3 and ERO1LB-EDARADD, also displayed suggestive differences in main effect size between the lean and obese strata. All top ranking loci for urate effect differences between BMI categories were novel and most had small magnitude but opposite direction effects between strata. They include the locus RBMS1-TANK (men, Pdifflean-overweight= 4.7 x 10-8), a region that has been associated with several obesity related traits, and TSPYL5 (men, Pdifflean-overweight= 9.1 x 10-8), regulating adipocytes-produced estradiol. The top-ranking known urate loci was ABCG2, the strongest known gout risk locus, with an effect halved in obese compared to lean men (Pdifflean-obese= 2 x 10-4). Finally, pathway analysis suggested a role for N-glycan biosynthesis as a prominent urate-associated pathway in the lean stratum. These results illustrate a potentially powerful way to monitor changes occurring in obesogenic environment. PMID:25811787

  20. Connecting Phrasal and Rhythmic Events: Evidence from Second Language Speech

    ERIC Educational Resources Information Center

    Nava, Emily Anne

    2010-01-01

    This dissertation investigates the relation between prosodic events at the phrasal level and component events at the rhythmic level. The overarching hypothesis is that the interaction among component rhythmic events gives rise to prosodic patterns at the phrasal level, while at the same time being constrained by the latter, and that in the case of…

  1. The Rhythmic Group, Liaison, Nouns and Verbs of French

    ERIC Educational Resources Information Center

    Ashby, William J.

    1975-01-01

    The "rhythmic group" in French (noun group or verb group) is described with examples. The aim is to find some relation between the morphophonological phenomena such as "liaison" occurring within such rhythmic groups and the syntactic structure of French. Available from Liber Laeromedel, Box 1205, S-22105 Lund, Sweden. (TL)

  2. The Impact of Rhythmic Entrainment on a Person with Autism.

    ERIC Educational Resources Information Center

    Orr, Tracy Jo; Myles, Brenda Smith; Carlson, Judith K.

    1998-01-01

    A study investigated the impact of rhythmic entrainment on an 11-year-old girl with autism who engaged in head jerking and screaming. Rhythmic entrainment intervention was more effective when she exhibited behavior that resulted from a moderate level of stress and less effective when stressors were more severe. (CR)

  3. Virtual lesion of right posterior superior temporal sulcus modulates conscious visual perception of fearful expressions in faces and bodies.

    PubMed

    Candidi, Matteo; Stienen, Bernard M C; Aglioti, Salvatore M; de Gelder, Beatrice

    2015-04-01

    The posterior Superior Temporal Suclus (pSTS) represents a central hub in the complex cerebral network for person perception and emotion recognition as also suggested by its heavy connections with face- and body-specific cortical (e.g., the fusiform face area, FFA and the extrastriate body area, EBA) and subcortical structures (e.g., amygdala). Information on whether pSTS is causatively involved in sustaining conscious visual perception of emotions expressed by faces and bodies is lacking. We explored this issue by combining a binocular rivalry procedure (where emotional and neutral face and body postures rivaled with house images) with off-line, 1-Hz repetitive transcranial magnetic stimulation (rTMS). We found that temporary inhibition of the right pSTS reduced perceptual dominance of fearful faces and increased perceptual dominance of fearful bodies, while leaving unaffected the perception of neutral face and body images. Inhibition of the vertex had no effect on conscious visual perception of neutral or emotional face or body stimuli. Thus, the right pSTS plays a causal role in shortening conscious vision of fearful faces and in prolonging conscious vision of fearful bodies. These results suggest that pSTS selectively modulates the activity of segregated networks involved in the conscious visual perception of emotional faces or bodies. We speculate that the opposite role of the right pSTS for conscious perception of fearful face and body may be explained by the different connections that this region entertains with face- and body-selective visual areas as well as with amygdalae and premotor regions.

  4. Environmental Coupling Modulates the Attractors of Rhythmic Coordination

    ERIC Educational Resources Information Center

    Kudo, Kazutoshi; Park, Hyeonsaeng; Kay, Bruce A.; Turvey, M. T.

    2006-01-01

    A simple instance of coupling behavior to the environment is oscillating the hands in pace with metronome beats. This environmental coupling can be weaker (1 beat per cycle) or stronger (2 beats per cycle). The authors examined whether strength of environmental coupling enhanced the stability of in-phase bimanual coordination. Detuning by…

  5. SU-E-T-540: Volumetric Modulated Total Body Irradiation Using a Rotational Lazy Susan-Like Immobilization System

    SciTech Connect

    Gu, X; Hrycushko, B; Lee, H; Lamphier, R; Jiang, S; Abdulrahman, R; Timmerman, R

    2014-06-01

    Purpose: Traditional extended SSD total body irradiation (TBI) techniques can be problematic in terms of patient comfort and/or dose uniformity. This work aims to develop a comfortable TBI technique that achieves a uniform dose distribution to the total body while reducing the dose to organs at risk for complications. Methods: To maximize patient comfort, a lazy Susan-like couch top immobilization system which rotates about a pivot point was developed. During CT simulation, a patient is immobilized by a Vac-Lok bag within the body frame. The patient is scanned head-first and then feet-first following 180° rotation of the frame. The two scans are imported into the Pinnacle treatment planning system and concatenated to give a full-body CT dataset. Treatment planning matches multiple isocenter volumetric modulated arc (VMAT) fields of the upper body and multiple isocenter parallel-opposed fields of the lower body. VMAT fields of the torso are optimized to satisfy lung dose constraints while achieving a therapeutic dose to the torso. The multiple isocenter VMAT fields are delivered with an indexed couch, followed by body frame rotation about the pivot point to treat the lower body isocenters. The treatment workflow was simulated with a Rando phantom, and the plan was mapped to a solid water slab phantom for point- and film-dose measurements at multiple locations. Results: The treatment plan of 12Gy over 8 fractions achieved 80.2% coverage of the total body volume within ±10% of the prescription dose. The mean lung dose was 8.1 Gy. All ion chamber measurements were within ±1.7% compared to the calculated point doses. All relative film dosimetry showed at least a 98.0% gamma passing rate using a 3mm/3% passing criteria. Conclusion: The proposed patient comfort-oriented TBI technique provides for a uniform dose distribution within the total body while reducing the dose to the lungs.

  6. Rhythmic biological systems under microgravity conditions.

    PubMed

    Johnsson, A; Eidesmo, T

    1989-01-01

    Rhythmic phenomena in biology cover a wide frequency spectrum. In Space, the rhythms will encounter microgravity conditions which can, therefore, be a valuable tool for their understanding. A review and discussion of important effects of gravity/absence of gravity on biological systems will be given. Convection will be emphasized as a mechanism which is drastically reduced in Space. Microgravity might also affect the coupling between individual oscillators in a multi-oscillatory system. The environmental interference with rhythms will be discussed with a simple feedback as a starting point. Model simulations will be presented and clinostat and microgravity-conditions will be discussed in a specific case, viz. the gravitropical system of plants which can show sustained oscillations.

  7. Rhythmicity, recurrence, and recovery of flagellar beating

    NASA Astrophysics Data System (ADS)

    Wan, Kirsty; Goldstein, Raymond

    2015-03-01

    The eukaryotic flagellum beats with apparently unfailing periodicity, yet responds rapidly to stimuli. Like the human heartbeat, flagellar oscillations are now known to be noisy. Using the unicellular alga Chlamydomonas reinhardtii, we explore three aspects of nonuniform flagellar beating. We report the existence of rhythmicity, waveform noise peaking at transitions between power and recovery strokes, and fluctuations of interbeat intervals that are correlated and even recurrent, with memory extending to hundreds of beats. These features are altered qualitatively by physiological perturbations. Further, we quantify the recovery of periodic breaststroke beating from transient hydrodynamic forcing. These results will help constrain microscopic theories on the origins and regulation of flagellar beating. Financial support is acknowledged from the EPSRC, ERC Advanced Investigator Grant No. 247333, and a Senior Investigator Award from the Wellcome Trust.

  8. Getting Down to Business: Auto Body Shop, Module 31. [Student Guide]. Entrepreneurship Training Components.

    ERIC Educational Resources Information Center

    McFarlane, Carolyn

    This module on owning and operating an auto repair shop is one of 36 in a series on entrepreneurship. The introduction tells the student what topics will be covered and suggests other modules to read in related occupations. Each unit includes student goals, a case study, and a discussion of the unit subject matter. Learning activities are divided…

  9. Rhythmic entrainment source separation: Optimizing analyses of neural responses to rhythmic sensory stimulation.

    PubMed

    Cohen, Michael X; Gulbinaite, Rasa

    2017-02-15

    Steady-state evoked potentials (SSEPs) are rhythmic brain responses to rhythmic sensory stimulation, and are often used to study perceptual and attentional processes. We present a data analysis method for maximizing the signal-to-noise ratio of the narrow-band steady-state response in the frequency and time-frequency domains. The method, termed rhythmic entrainment source separation (RESS), is based on denoising source separation approaches that take advantage of the simultaneous but differential projection of neural activity to multiple electrodes or sensors. Our approach is a combination and extension of existing multivariate source separation methods. We demonstrate that RESS performs well on both simulated and empirical data, and outperforms conventional SSEP analysis methods based on selecting electrodes with the strongest SSEP response, as well as several other linear spatial filters. We also discuss the potential confound of overfitting, whereby the filter captures noise in absence of a signal. Matlab scripts are available to replicate and extend our simulations and methods. We conclude with some practical advice for optimizing SSEP data analyses and interpreting the results.

  10. Serotonin Receptors Expressed in Drosophila Mushroom Bodies Differentially Modulate Larval Locomotion

    PubMed Central

    Silva, Bryon; Goles, Nicolás I.; Varas, Rodrigo; Campusano, Jorge M.

    2014-01-01

    Drosophila melanogaster has been successfully used as a simple model to study the cellular and molecular mechanisms underlying behaviors, including the generation of motor programs. Thus, it has been shown that, as in vertebrates, CNS biogenic amines (BA) including serotonin (5HT) participate in motor control in Drosophila. Several evidence show that BA systems innervate an important association area in the insect brain previously associated to the planning and/or execution of motor programs, the Mushroom Bodies (MB). The main objective of this work is to evaluate the contribution of 5HT and its receptors expressed in MB to motor behavior in fly larva. Locomotion was evaluated using an automated tracking system, in Drosophila larvae (3rd-instar) exposed to drugs that affect the serotonergic neuronal transmission: alpha-methyl-L-dopa, MDMA and fluoxetine. In addition, animals expressing mutations in the 5HT biosynthetic enzymes or in any of the previously identified receptors for this amine (5HT1AR, 5HT1BR, 5HT2R and 5HT7R) were evaluated in their locomotion. Finally, RNAi directed to the Drosophila 5HT receptor transcripts were expressed in MB and the effect of this manipulation on motor behavior was assessed. Data obtained in the mutants and in animals exposed to the serotonergic drugs, suggest that 5HT systems are important regulators of motor programs in fly larvae. Studies carried out in animals pan-neuronally expressing the RNAi for each of the serotonergic receptors, support this idea and further suggest that CNS 5HT pathways play a role in motor control. Moreover, animals expressing an RNAi for 5HT1BR, 5HT2R and 5HT7R in MB show increased motor behavior, while no effect is observed when the RNAi for 5HT1AR is expressed in this region. Thus, our data suggest that CNS 5HT systems are involved in motor control, and that 5HT receptors expressed in MB differentially modulate motor programs in fly larvae. PMID:24586928

  11. Menopausal hot flashes: Randomness or rhythmicity

    NASA Astrophysics Data System (ADS)

    Kronenberg, Fredi

    1991-10-01

    Menopausal hot flashes are episodes of flushing, increased heart rate, skin blood flow and skin temperature, and a sensation of heat. The thermoregulatory and cardiovascular concomitants of hot flashes are associated with peaks in the levels of various hormones and neurotransmitters in the peripheral circulation. Although hot flashes affect about 75% of women, and are the primary reason that women at menopause seek medical attention, the mechanism of hot flashes is still not understood. Hot flashes vary in frequency and intensity both within and between individuals, and have been thought of as occurring randomly. Yet, some women report that their hot flashes are worse at a particular time of day or year. Initial examination of subjects' recordings of their hot flashes showed diurnal patterns of hot flash occurrence. There also seems to be a diurnal rhythm of hot flash intensity. Continuous physiological monitoring of hot flashes is facilitating the analysis of these patterns, which is revealing circadian and ultradian periodicities. The occurrence of hot flashes can be modulated by external and internal factors, including ambient temperature and fever. Rhythms of thermoregulatory and endocrine functions also may influence hot flash patterns. Examination of the interrelationships between the various systems of the body involved in hot flashes, and a multidisciplinary approach to the analysis of hot flash patterns, will aid our understanding of this complex phenomenon.

  12. Estradiol: a rhythmic, inhibitory, indirect control of meal size.

    PubMed

    Eckel, Lisa A

    2004-08-01

    The classic analyses of the inhibitory effects of cholecystokinin (CCK) on meal size, conducted by Professor Gerard P. Smith and his colleagues at the Bourne Laboratory, inspired my initial interest in this field. My current research, which investigates the role of estradiol in the control of meal size, continues to be guided by Gerry's thoughtful, scientific approach to the study of ingestive behavior. In 1996, the year I arrived as a Postdoctoral Fellow at the Bourne Laboratory, Gerry published a new theory of the controls of meal size. In this important paper, Gerry proposed that the controls of meal size can be either direct or indirect. He argued that direct controls of meal size interact with peripheral, preabsorptive receptors that are sensitive to the chemical, mechanical, and colligative properties of ingested food and that indirect controls of meal size function to modulate the activity of direct controls. The purpose of this review is to illustrate how Gerry's theory has guided much of what is known about the mechanism by which estradiol inhibits food intake in female rats. I will provide evidence, primarily from behavioral studies of gonadally intact and ovariectomized rats, that estradiol exerts phasic and tonic inhibitory effects on food intake by acting as a rhythmic, inhibitory, indirect control of meal size.

  13. Situational influences on rhythmicity in speech, music, and their interaction

    PubMed Central

    Hawkins, Sarah

    2014-01-01

    Brain processes underlying the production and perception of rhythm indicate considerable flexibility in how physical signals are interpreted. This paper explores how that flexibility might play out in rhythmicity in speech and music. There is much in common across the two domains, but there are also significant differences. Interpretations are explored that reconcile some of the differences, particularly with respect to how functional properties modify the rhythmicity of speech, within limits imposed by its structural constraints. Functional and structural differences mean that music is typically more rhythmic than speech, and that speech will be more rhythmic when the emotions are more strongly engaged, or intended to be engaged. The influence of rhythmicity on attention is acknowledged, and it is suggested that local increases in rhythmicity occur at times when attention is required to coordinate joint action, whether in talking or music-making. Evidence is presented which suggests that while these short phases of heightened rhythmical behaviour are crucial to the success of transitions in communicative interaction, their modality is immaterial: they all function to enhance precise temporal prediction and hence tightly coordinated joint action. PMID:25385776

  14. Paired Synchronous Rhythmic Finger Tapping without an External Timing Cue Shows Greater Speed Increases Relative to Those for Solo Tapping

    PubMed Central

    Okano, Masahiro; Shinya, Masahiro; Kudo, Kazutoshi

    2017-01-01

    In solo synchronization-continuation (SC) tasks, intertap intervals (ITI) are known to drift from the initial tempo. It has been demonstrated that people in paired and group contexts modulate their action timing unconsciously in various situations such as choice reaction tasks, rhythmic body sway, and hand clapping in concerts, which suggests the possibility that ITI drift is also affected by paired context. We conducted solo and paired SC tapping experiments with three tempos (75, 120, and 200 bpm) and examined whether tempo-keeping performance changed according to tempo and/or the number of players. Results indicated that those tapping in the paired conditions were faster, relative to those observed in the solo conditions, for all tempos. For the faster participants, the degree of ITI drift in the solo conditions was strongly correlated with that in the paired conditions. Regression analyses suggested that both faster and slower participants adapted their tap timing to that of their partners. A possible explanation for these results is that the participants reset the phase of their internal clocks according to the faster beat between their own tap and the partners’ tap. Our results indicated that paired context could bias the direction of ITI drift toward decreasing. PMID:28276461

  15. Contactless mapping of rhythmical phenomena in tissue perfusion using PPGI

    NASA Astrophysics Data System (ADS)

    Huelsbusch, Markus; Blazek, Vladimir

    2002-04-01

    This paper presents the experimental setup and preliminary results of a near infrared CCD camera based Photoplethysmography Imaging (PPGI) system, which has been shown to be suitable for contactless and spatially resolved assessment of rhythmical blood volume changes in the skin. To visualize the complex rhythmical patterns in the dermal perfusion the Wavelet Transform is utilized. It is able to jointly assess time and frequency behavior of signals and thus allows to analyze instationary oscillations and variabilities in the different human rhythmics. The presented system is expected to provide new insights into the functional sequences of physiological tissue perfusion as well as of the perfusion status in ulcer formation and wound healing.

  16. Guided Saccades Modulate Face- and Body-Sensitive Activation in the Occipitotemporal Cortex during Social Perception

    ERIC Educational Resources Information Center

    Morris, James P.; Green, Steven R.; Marion, Brian; McCarthy, Gregory

    2008-01-01

    Functional magnetic resonance imaging (fMRI) has identified distinct brain regions in ventral occipitotemporal cortex (VOTC) and lateral occipitotemporal cortex (LOTC) that are differentially activated by pictures of faces and bodies. Recent work from our laboratory has shown that the strong LOTC activation evoked by bodies in which the face is…

  17. Rhythmic Extended Kalman Filter for Gait Rehabilitation Motion Estimation and Segmentation.

    PubMed

    Joukov, Vladimir; Bonnet, Vincent; Karg, Michelle; Venture, Gentiane; Kulic, Dana

    2017-01-26

    This work proposes a method to enable the use of non-intrusive, small, wearable, wireless sensors to estimate the pose of the lower body during gait and other periodic motions and to extract objective performance measures useful for physiotherapy. The Rhythmic Extended Kalman Filter (Rhythmic- EKF) algorithm is developed to estimate the pose, learn an individualized model of periodic movement over time, and use the learned model to improve pose estimation. The proposed approach learns a canonical dynamical system model of the movement during online observation, which is used to accurately model the acceleration during pose estimation. The canonical dynamical system models the motion as a periodic signal. The estimated phase and frequency of the motion also allow the proposed approach to segment the motion into repetitions and extract useful features such as gait symmetry, step length, and mean joint movement and variance. The algorithm is shown to outperform the extended Kalman filter in simulation, on healthy participant data, and stroke patient data. For the healthy participant marching dataset, the Rhythmic-EKF improves joint acceleration and velocity estimates over regular EKF by 40% and 37% respectively, estimates joint angles with 2.4° RMSE, and segments the motion into repetitions with 96% accuracy.

  18. Modulation of the hypoxic sensory response of the carotid body by 5-hydroxytryptamine: role of the 5-HT2 receptor.

    PubMed

    Jacono, F J; Peng, Y-J; Kumar, G K; Prabhakar, N R

    2005-02-15

    Previous studies have shown that glomus cells of the carotid body express 5-hydroxytryptamine (5-HT). The aim of this study was to elucidate the role of 5-HT on the hypoxic sensory response (HSR) of the carotid body. Sensory activity was recorded from multi-fiber (n=16) and single-fiber (n=8) preparations of ex vivo carotid bodies harvested from anesthetized, adult rats. 5-HT (3 microM) had no significant effect on the magnitude or on the onset of the HSR. However, 5-HT consistently prolonged the time necessary for the sensory activity to return to baseline following the termination of the hypoxic challenge. Ketanserin (40 microM), a 5-HT2 receptor antagonist completely prevented 5-HT-induced prolongation of the HSR, whereas had no effect on the control HSR (onset, magnitude, and time for decay without 5-HT). Carotid bodies expressed 5-HT, but hypoxia did not facilitate 5-HT release. These observations suggest that 5-HT is not critical for the HSR of the rat carotid body, but it modulates the dynamics of the HSR via its action on 5-HT2 receptors.

  19. The relative contribution of physical fitness to the technical execution score in youth rhythmic gymnastics

    PubMed Central

    Donti, Olyvia; Kritikou, Maria; Donti, Anastasia; Theodorakou, Kalliopi

    2016-01-01

    Abstract This study examined the association between physical fitness and a technical execution score in rhythmic gymnasts varying in the performance level. Forty-six young rhythmic gymnasts (age: 9.9 ±1.3 years) were divided into two groups (qualifiers, n=24 and non-qualifiers, n=22) based on the results of the National Championships. Gymnasts underwent a series of physical fitness tests and technical execution was evaluated in a routine without apparatus. There were significant differences between qualifiers and non-qualifiers in the technical execution score (p=0.01, d=1.0), shoulder flexion (p=0.01, d=0.8), straight leg raise (p=0.004, d=0.9), sideways leg extension (p=0.002, d=0.9) and body fat (p=.021, d=0.7), but no differences were found in muscular endurance and jumping performance. The technical execution score for the non-qualifiers was significantly correlated with shoulder extension (r=0.423, p<0.05), sideways leg extension (r=0.687, p<0.01), push ups (r=0.437, p<0.05) and body fat (r=0.642, p<0.01), while there was only one significant correlation with sideways leg extension (r=0.467, p<0.05) for the qualifiers. Multiple regression analysis revealed that sideways leg extension, body fat, and push ups accounted for a large part (62.9%) of the variance in the technical execution score for the non-qualifiers, while for the qualifiers, only 37.3% of the variance in the technical execution score was accounted for by sideways leg extension and spine flexibility. In conclusion, flexibility and body composition can effectively discriminate between qualifiers and non-qualifiers in youth rhythmic gymnastics. At the lower level of performance (non-qualifiers), physical fitness seems to have a greater effect on the technical execution score. PMID:28149377

  20. Statistics concerning the Apollo command module water landing, including the probability of occurrence of various impact conditions, sucessful impact, and body X-axis loads

    NASA Technical Reports Server (NTRS)

    Whitnah, A. M.; Howes, D. B.

    1971-01-01

    Statistical information for the Apollo command module water landings is presented. This information includes the probability of occurrence of various impact conditions, a successful impact, and body X-axis loads of various magnitudes.

  1. Rhythmic complexity and predictive coding: a novel approach to modeling rhythm and meter perception in music

    PubMed Central

    Vuust, Peter; Witek, Maria A. G.

    2014-01-01

    Musical rhythm, consisting of apparently abstract intervals of accented temporal events, has a remarkable capacity to move our minds and bodies. How does the cognitive system enable our experiences of rhythmically complex music? In this paper, we describe some common forms of rhythmic complexity in music and propose the theory of predictive coding (PC) as a framework for understanding how rhythm and rhythmic complexity are processed in the brain. We also consider why we feel so compelled by rhythmic tension in music. First, we consider theories of rhythm and meter perception, which provide hierarchical and computational approaches to modeling. Second, we present the theory of PC, which posits a hierarchical organization of brain responses reflecting fundamental, survival-related mechanisms associated with predicting future events. According to this theory, perception and learning is manifested through the brain’s Bayesian minimization of the error between the input to the brain and the brain’s prior expectations. Third, we develop a PC model of musical rhythm, in which rhythm perception is conceptualized as an interaction between what is heard (“rhythm”) and the brain’s anticipatory structuring of music (“meter”). Finally, we review empirical studies of the neural and behavioral effects of syncopation, polyrhythm and groove, and propose how these studies can be seen as special cases of the PC theory. We argue that musical rhythm exploits the brain’s general principles of prediction and propose that pleasure and desire for sensorimotor synchronization from musical rhythm may be a result of such mechanisms. PMID:25324813

  2. Circadian rhythmicity as a predictor of weight-loss effectiveness

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Some of the major challenges associated with successful dietary weight management include the identification of individuals not responsive to specific interventions. The aim was to investigate the potential relationship between weight loss and circadian rhythmicity, using wrist temperature and actim...

  3. Rhythmic Behavior in the Hierarchy of Responses of Preschool Children

    ERIC Educational Resources Information Center

    Zern, David; Taylor, Amie Lou

    1973-01-01

    Data shows that the nursery school child will resort to rhythmic behavior more often in a situation with significant environmental constraints''; such behavior has an analgesic or a general soothing influence.'' (Author/SP)

  4. Procedure of rectal temperature measurement affects brain, muscle, skin, and body temperatures and modulates the effects of intravenous cocaine.

    PubMed

    Bae, David D; Brown, P Leon; Kiyatkin, Eugene A

    2007-06-18

    Rectal probe thermometry is commonly used to measure body core temperature in rodents because of its ease of use. Although previous studies suggest that rectal measurement is stressful and results in long-lasting elevations in body temperatures, we evaluated how this procedure affects brain, muscle, skin, and core temperatures measured with chronically implanted thermocouple electrodes in rats. Our data suggest that the procedure of rectal measurement results in powerful locomotor activation, rapid and strong increases in brain, muscle, and deep body temperatures, as well as a biphasic, down-up fluctuation in skin temperature, matching the response pattern observed during tail-pinch, a representative stressful procedure. This response, moreover, did not habituate after repeated day-to-day testing. Repeated rectal probe insertions also modified temperature responses induced by intravenous cocaine. Under quiet resting conditions, cocaine moderately increased brain, muscle, and deep body temperatures. However, during repeated rectal measurements, which increased temperatures, cocaine induced both hyperthermic and hypothermic responses. Direct comparisons revealed that body temperatures measured by a rectal probe are typically lower (approximately 0.6 degrees C) and more variable than body temperatures recorded by chronically implanted electrodes; the difference is smaller at low and greater at high basal temperatures. Because of this difference and temperature increases induced by the rectal probe per se, cocaine had no significant effect on rectal temperatures compared to control animals exposed to repeated rectal probes. Therefore, although rectal temperature measurements provide a decent correlation with directly measured deep body temperatures, the arousing influence of this procedure may drastically modulate the effects of other arousing stimuli and drugs.

  5. Rhythmic and non-rhythmic attractors in asynchronous random Boolean networks.

    PubMed

    Di Paolo, E A

    2001-03-01

    In multi-component, discrete systems, such as Boolean networks and cellular automata, the scheme of updating of the individual elements plays a crucial role in determining their dynamic properties and their suitability as models of complex phenomena. Many interesting properties of these systems rely heavily on the use of synchronous updating of the individual elements. Considerations of parsimony have motivated the claim that, if the natural systems being modelled lack any clear evidence of synchronously driven elements, then random asynchronous updating should be used by default. The introduction of a random element precludes the possibility of strictly cyclic behaviour. In principle, this poses the question of whether asynchronously driven Boolean networks, cellular automata, etc., are inherently bad choices at the time of modelling rhythmic phenomena. This paper focuses on this subsidiary issue for the case of Asynchronous Random Boolean Networks (ARBNs). It defines measures of pseudo-periodicity between states and sufficiently relaxed statistical constraints. These measures are used to guide a genetic algorithm to find appropriate examples. Success in this search for a number of cases, and the subsequent statistical analysis lead to the conclusion that ARBNs can indeed be used as models of co-ordinated rhythmic phenomena, which may be stronger precisely because of their in-built asynchrony. The same technique is used to find non-stationary attractors that show no rhythm. Evidence suggests that the latter are more abundant than rhythmic attractor. The methodology is flexible, and allows for more demanding statistical conditions for defining pseudo-periodicity, and constraining the evolutionary search.

  6. [Intensity-modulated radiation therapy and stereotactic body radiation therapy for head and neck tumors: evidence-based medicine].

    PubMed

    Lapierre, A; Martin, F; Lapeyre, M

    2014-10-01

    Over the last decade, there have been many technical advances in radiation therapy, such as the spread of intensity-modulated conformal radiotherapy, and the rise of stereotactic body radiation therapy. By allowing better dose-to-target conformation and thus better organs at risk-sparing, these techniques seem very promising, particularly in the field of head and neck tumors. The present work aims at analyzing the level of evidence and recommendation supporting the use of high-technology radiotherapy in head and neck neoplasms, by reviewing the available literature.

  7. Head Exposure to Cold during Whole-Body Cryostimulation: Influence on Thermal Response and Autonomic Modulation.

    PubMed

    Louis, Julien; Schaal, Karine; Bieuzen, François; Le Meur, Yann; Filliard, Jean-Robert; Volondat, Marielle; Brisswalter, Jeanick; Hausswirth, Christophe

    2015-01-01

    Recent research on whole-body cryotherapy has hypothesized a major responsibility of head cooling in the physiological changes classically reported after a cryostimulation session. The aim of this experiment was to verify this hypothesis by studying the influence of exposing the head to cold during whole-body cryostimulation sessions, on the thermal response and the autonomic nervous system (ANS). Over five consecutive days, two groups of 10 participants performed one whole-body cryostimulation session daily, in one of two different systems; one exposing the whole-body to cold (whole-body cryostimulation, WBC), and the other exposing the whole-body except the head (partial-body cryostimulation, PBC).10 participants constituted a control group (CON) not receiving any cryostimulation. In order to isolate the head-cooling effect on recorded variables, it was ensured that the WBC and PBC systems induced the same decrease in skin temperature for all body regions (mean decrease over the 5 exposures: -8.6°C ± 1.3°C and -8.3 ± 0.7°C for WBC and PBC, respectively), which persisted up to 20-min after the sessions (P20). The WBC sessions caused an almost certain decrease in tympanic temperature from Pre to P20 (-0.28 ± 0.11°C), while it only decreased at P20 (-0.14 ± 0.05°C) after PBC sessions. Heart rate almost certainly decreased after PBC (-8.6%) and WBC (-12.3%) sessions. Resting vagal-related heart rate variability indices (the root-mean square difference of successive normal R-R intervals, RMSSD, and high frequency band, HF) were very likely to almost certainly increased after PBC (RMSSD:+49.1%, HF: +123.3%) and WBC (RMSSD: +38.8%, HF:+70.3%). Plasma norepinephrine concentration was likely increased in similar proportions after PBC and WBC, but only after the first session. Both cryostimulation techniques stimulated the ANS with a predominance of parasympathetic tone activation from the first to the fifth session and in slightly greater proportion with WBC than

  8. Skeletal muscle carnitine loading increases energy expenditure, modulates fuel metabolism gene networks and prevents body fat accumulation in humans

    PubMed Central

    Stephens, Francis B; Wall, Benjamin T; Marimuthu, Kanagaraj; Shannon, Chris E; Constantin-Teodosiu, Dumitru; Macdonald, Ian A; Greenhaff, Paul L

    2013-01-01

    Twelve weeks of daily l-carnitine and carbohydrate feeding in humans increases skeletal muscle total carnitine content, and prevents body mass accrual associated with carbohydrate feeding alone. Here we determined the influence of l-carnitine and carbohydrate feeding on energy metabolism, body fat mass and muscle expression of fuel metabolism genes. Twelve males exercised at 50% maximal oxygen consumption for 30 min once before and once after 12 weeks of twice daily feeding of 80 g carbohydrate (Control, n= 6) or 1.36 g l-carnitine + 80 g carbohydrate (Carnitine, n= 6). Maximal carnitine palmitolytransferase 1 (CPT1) activity remained similar in both groups over 12 weeks. However, whereas muscle total carnitine, long-chain acyl-CoA and whole-body energy expenditure did not change over 12 weeks in Control, they increased in Carnitine by 20%, 200% and 6%, respectively (P < 0.05). Moreover, body mass and whole-body fat mass (dual-energy X-ray absorptiometry) increased over 12 weeks in Control by 1.9 and 1.8 kg, respectively (P < 0.05), but did not change in Carnitine. Seventy-three of 187 genes relating to fuel metabolism were upregulated in Carnitine vs. Control after 12 weeks, with ‘insulin signalling’, ‘peroxisome proliferator-activated receptor signalling’ and ‘fatty acid metabolism’ as the three most enriched pathways in gene functional analysis. In conclusion, increasing muscle total carnitine in healthy humans can modulate muscle metabolism, energy expenditure and body composition over a prolonged period, which is entirely consistent with a carnitine-mediated increase in muscle long-chain acyl-group translocation via CPT1. Implications to health warrant further investigation, particularly in obese individuals who have a reduced reliance on muscle fat oxidation during low-intensity exercise. PMID:23818692

  9. Octopamine promotes rhythmicity but not synchrony in a bilateral pair of bursting motor neurons in the feeding circuit of Aplysia

    PubMed Central

    Martínez-Rubio, C.; Serrano, G. E.; Miller, M. W.

    2010-01-01

    Octopamine-like immunoreactivity was localized to a limited number (<40) of neurons in the Aplysia central nervous system, including three neurons in the paired buccal ganglia (BG) that control feeding movements. Application of octopamine (OA) to the BG circuit produced concentration-dependent (10−8–10−4 mol l−1) modulatory actions on the spontaneous burst activity of the bilaterally paired B67 pharyngeal motor neurons (MNs). OA increased B67's burst duration and the number of impulses per burst. These effects reflected actions of OA on the intrinsic tetrodotoxin-resistant driver potential (DP) that underlies B67 bursting. In addition to its effects on B67's burst parameters, OA also increased the rate and regularity of burst timing. Although the bilaterally paired B67 MNs both exhibited rhythmic bursting in the presence of OA, they did not become synchronized. In this respect, the response to OA differed from that of dopamine, another modulator of the feeding motor network, which produces both rhythmicity and synchrony of bursting in the paired B67 neurons. It is proposed that modulators can regulate burst synchrony of MNs by exerting a dual control over their intrinsic rhythmicity and their reciprocal capacity to generate membrane potential perturbations. In this simple system, dopaminergic and octopaminergic modulation could influence whether pharyngeal contractions occur in a bilaterally synchronous or asynchronous fashion. PMID:20228355

  10. Composite body movements modulate numerical cognition: evidence from the motion-numerical compatibility effect

    PubMed Central

    Cheng, Xiaorong; Ge, Hui; Andoni, Deljfina; Ding, Xianfeng; Fan, Zhao

    2015-01-01

    A recent hierarchical model of numerical processing, initiated by Fischer and Brugger (2011) and Fischer (2012), suggested that situated factors, such as different body postures and body movements, can influence the magnitude representation and bias numerical processing. Indeed, Loetscher et al. (2008) found that participants’ behavior in a random number generation task was biased by head rotations. More small numbers were reported after leftward than rightward head turns, i.e., a motion-numerical compatibility effect. Here, by carrying out two experiments, we explored whether similar motion-numerical compatibility effects exist for movements of other important body components, e.g., arms, and for composite body movements as well, which are basis for complex human activities in many ecologically meaningful situations. In Experiment 1, a motion-numerical compatibility effect was observed for lateral rotations of two body components, i.e., the head and arms. Relatively large numbers were reported after making rightward compared to leftward movements for both lateral head and arm turns. The motion-numerical compatibility effect was observed again in Experiment 2 when participants were asked to perform composite body movements of congruent movement directions, e.g., simultaneous head left turns and arm left turns. However, it disappeared when the movement directions were incongruent, e.g., simultaneous head left turns and arm right turns. Taken together, our results extended Loetscher et al.’s (2008) finding by demonstrating that their effect is effector-general and exists for arm movements. Moreover, our study reveals for the first time that the impact of spatial information on numerical processing induced by each of the two sensorimotor-based situated factors, e.g., a lateral head turn and a lateral arm turn, can cancel each other out. PMID:26594188

  11. Human body frequency modulation by 0.9% sodium chloride solutions: a new paradigm and perspective for human health.

    PubMed

    Sudan, B J

    2000-08-01

    This case study demonstrates that the normal human body frequency, which can be disturbed by electromagnetic influences of the environment, can be modulated by 0.9% sodium chloride solutions (physiological saline) and that occurrence of allergic reactions have subsequently been suppressed as a result of this modulation. The use of distilled water as control showed no effect on occurrence of allergic reactions. Further observations on the growth of various plants in a greenhouse exposed to various geomagnetic fields support the previous observations on humans. The neutralization of electromagnetic influences on humans using 0.9% sodium chloride solution or by enclosure of plants within a copper wire Faraday cage resulting in a normal and uniform growth of plants as compared with disturbed and irregular growth in unenclosed controls, is demonstrated. These original observations propose a new strategy to suppress or prevent allergic reactions and possibly other effects observed in various human pathologies in relation to a disturbance of human body frequencies. It is hypothesized that the double helix structure of desoxyribonucleic acid (DNA) could be modified by environmental electromagnetic fields and that disresonance between the two chains of DNA could lead to the expression of specific pathology.

  12. cAMP signalling in mushroom bodies modulates temperature preference behaviour in Drosophila.

    PubMed

    Hong, Sung-Tae; Bang, Sunhoe; Hyun, Seogang; Kang, Jongkyun; Jeong, Kyunghwa; Paik, Donggi; Chung, Jongkyeong; Kim, Jaeseob

    2008-08-07

    Homoiotherms, for example mammals, regulate their body temperature with physiological responses such as a change of metabolic rate and sweating. In contrast, the body temperature of poikilotherms, for example Drosophila, is the result of heat exchange with the surrounding environment as a result of the large ratio of surface area to volume of their bodies. Accordingly, these animals must instinctively move to places with an environmental temperature as close as possible to their genetically determined desired temperature. The temperature that Drosophila instinctively prefers has a function equivalent to the 'set point' temperature in mammals. Although various temperature-gated TRP channels have been discovered, molecular and cellular components in Drosophila brain responsible for determining the desired temperature remain unknown. We identified these components by performing a large-scale genetic screen of temperature preference behaviour (TPB) in Drosophila. In parallel, we mapped areas of the Drosophila brain controlling TPB by targeted inactivation of neurons with tetanus toxin and a potassium channel (Kir2.1) driven with various brain-specific GAL4s. Here we show that mushroom bodies (MBs) and the cyclic AMP-cAMP-dependent protein kinase A (cAMP-PKA) pathway are essential for controlling TPB. Furthermore, targeted expression of cAMP-PKA pathway components in only the MB was sufficient to rescue abnormal TPB of the corresponding mutants. Preferred temperatures were affected by the level of cAMP and PKA activity in the MBs in various PKA pathway mutants.

  13. Rhythmic Leptin Is Required for Weight Gain from Circadian Desynchronized Feeding in the Mouse

    PubMed Central

    Arble, Deanna Marie; Vitaterna, Martha Hotz; Turek, Fred W.

    2011-01-01

    The neuroendocrine and metabolic effects of leptin have been extensively researched since the discovery, and the later identification, of the leptin gene mutated within the ob/ob mouse. Leptin is required for optimal health in a number of physiological systems (e.g. fertility, bone density, body weight regulation). Despite the extensive leptin literature and many observations of leptin’s cyclical pattern over the 24-hour day, few studies have specifically examined how the circadian rhythm of leptin may be essential to leptin signaling and health. Here we present data indicating that a rhythmic leptin profile (e.g. 1 peak every 24 hours) leads to excessive weight gain during desynchronized feeding whereas non-rhythmic leptin provided in a continuous manner does not lead to excessive body weight gain under similar feeding conditions. This study suggests that feeding time can interact with leptin’s endogenous rhythm to influence metabolic signals, specifically leading to excessive body weight gains during ‘wrongly’ timed feeding. PMID:21949859

  14. Implementation of a volumetric modulated arc therapy treatment planning solution for kidney and adrenal stereotactic body radiation therapy.

    PubMed

    Sonier, Marcus; Chu, William; Lalani, Nafisha; Erler, Darby; Cheung, Patrick; Korol, Renee

    2016-01-01

    To develop a volumetric modulated arc therapy (VMAT) treatment planning solution in the treatment of primary renal cell carcinoma and oligometastatic adrenal lesions with stereotactic body radiation therapy. Single-arc VMAT plans (n = 5) were compared with clinically delivered step-and-shoot intensity-modulated radiotherapy (IMRT) with planning target volume coverage normalized between techniques. Target volume conformity, organ-at-risk (OAR) dose, treatment time, and monitor units were compared. A VMAT planning solution, created from a combination of arc settings and optimization constraints, auto-generated treatment plans in a single optimization. The treatment planning solution was evaluated on 15 consecutive patients receiving kidney and adrenal stereotactic body radiation therapy. Treatment time was reduced from 13.0 ± 2.6 to 4.0 ± 0.9 minutes for IMRT and VMAT, respectively. The VMAT planning solution generated treatment plans with increased target homogeneity, improved 95% conformity index, and a reduced maximum point dose to nearby OARs but with increased intermediate dose to distant OARs. The conformity of the 95% isodose improved from 1.32 ± 0.39 to 1.12 ± 0.05 for IMRT and VMAT treatment plans, respectively. Evaluation of the planning solution showed clinically acceptable dose distributions for 13 of 15 cases with tight conformity of the prescription isodose to the planning target volume of 1.07 ± 0.04, delivering minimal dose to OARs. The introduction of a stereotactic body radiation therapy VMAT treatment planning solution improves the efficiency of planning and delivery time, producing treatment plans of comparable or superior quality to IMRT in the case of primary renal cell carcinoma and oligometastatic adrenal lesions.

  15. Body temperature modulates the antioxidant and acute immune responses to exercise.

    PubMed

    Mestre-Alfaro, Antonia; Ferrer, Miguel D; Banquells, Montserrat; Riera, Joan; Drobnic, Franchek; Sureda, Antoni; Tur, Josep A; Pons, Antoni

    2012-06-01

    The aim of this study was to determine the effects of whole body heat in combination with exercise on the oxidative stress and acute phase immune response. Nine male endurance-trained athletes voluntarily performed two running bouts of 45 minutes at 75-80% of VO(2max) in a climatic chamber in two conditions: cold and hot humid environment. Leukocyte, neutrophil and basophil counts significantly rose after exercise in both environments; it was significantly greater in the hot environment. Lymphocyte and neutrophil antioxidant enzyme activities and carbonyl index significantly increased or decreased after exercise only in the hot environment, respectively. The lymphocytes expression of catalase, Hsp72 and CuZn-superoxide dismutase was increased in the hot environment and Sirt3 in the cold environment, mainly during recovery. In conclusion, the increased core body temperature results in the acute phase immune response associated to intense exercise and in the immune cell adaptations to counteract the oxidative stress situation.

  16. TH-C-12A-04: Dosimetric Evaluation of a Modulated Arc Technique for Total Body Irradiation

    SciTech Connect

    Tsiamas, P; Czerminska, M; Makrigiorgos, G; Karen, M; Zygmanski, P

    2014-06-15

    Purpose: A simplified Total Body Irradiation (TBI) was developed to work with minimal requirements in a compact linac room without custom motorized TBI couch. Results were compared to our existing fixed-gantry double 4 MV linac TBI system with prone patient and simultaneous AP/PA irradiation. Methods: Modulated arc irradiates patient positioned in prone/supine positions along the craniocaudal axis. A simplified inverse planning method developed to optimize dose rate as a function of gantry angle for various patient sizes without the need of graphical 3D treatment planning system. This method can be easily adapted and used with minimal resources. Fixed maximum field size (40×40 cm2) is used to decrease radiation delivery time. Dose rate as a function of gantry angle is optimized to result in uniform dose inside rectangular phantoms of various sizes and a custom VMAT DICOM plans were generated using a DICOM editor tool. Monte Carlo simulations, film and ionization chamber dosimetry for various setups were used to derive and test an extended SSD beam model based on PDD/OAR profiles for Varian 6EX/ TX. Measurements were obtained using solid water phantoms. Dose rate modulation function was determined for various size patients (100cm − 200cm). Depending on the size of the patient arc range varied from 100° to 120°. Results: A PDD/OAR based beam model for modulated arc TBI therapy was developed. Lateral dose profiles produced were similar to profiles of our existing TBI facility. Calculated delivery time and full arc depended on the size of the patient (∼8min/ 100° − 10min/ 120°, 100 cGy). Dose heterogeneity varied by about ±5% − ±10% depending on the patient size and distance to the surface (buildup region). Conclusion: TBI using simplified modulated arc along craniocaudal axis of different size patients positioned on the floor can be achieved without graphical / inverse 3D planning.

  17. Is there evidence for nonthermal modulation of whole body heat loss during intermittent exercise?

    PubMed

    Kenny, Glen P; Gagnon, Daniel

    2010-07-01

    This study compared the effect of active, passive, and inactive recoveries on whole body evaporative and dry heat loss responses during intermittent exercise at an air temperature of 30 degrees C and a relative humidity of 20%. Nine males performed three 15-min bouts of upright seated cycling at a fixed external workload of 150 W. The exercise bouts were separated by three 15-min recoveries during which participants 1) performed loadless pedaling (active recovery), 2) had their lower limbs passively compressed with inflatable sleeves (passive recovery), or 3) remained upright seated on the cycle ergometer (inactive recovery). Combined direct and indirect calorimetry was employed to measure rates of whole body evaporative heat loss (EHL) and metabolic heat production (M-W). Mean body temperature (T(b)) was calculated from esophageal and mean skin temperatures, and mean arterial pressure (MAP) was measured continuously. Active and passive recoveries both reversed the reduction in MAP associated with inactive recovery (P body

  18. Regular exercise modulates obesity factors and body composition in sturdy men

    PubMed Central

    Ko, Il-Gyu; Choi, Pil-Byung

    2013-01-01

    The purpose of this study was to find the change and correlation between obesity factors and body composition according to regular exercise. Thirty-six sturdy men at twenty years old in ‘K’ university students were participated in this study. The subjects were randomly divided into two groups (n= 18 in each group): control group and regular exercise group. Exercise program composed of three programs: warm-up (10 min), work-out (30–60 min), cool-down (10 min), and categorized by five days per week for eight weeks. Aerobic exercise using a treadmill at 60% of heart rate reserve was performed, and weight training was composed of nine different exercises for the large muscles. Before the performing regular exercise, there was no significant difference between control and regular exercise groups. In the present results, 8 weeks regular exercise significantly decreased leptin, weight, fat mass, % fat, waist to hip ratio (WHR), and body mass index (BMI) more than compared to before performing regular exercise, whereas significantly enhanced lean mass more than compared to before performing regular exercise. Furthermore, regular exercise group reduced leptin, weight, fat mass, % fat, WHR, and BMI compared to control group in the post test. In the correlation of obesity-related factors and body composition, tumor necrosis factor-α (TNF-α) showed correlation with weight, lean mass, and fat mass after performing regular exercise. Here in this study, we suggest that regular exercise is a valuable tool for the improvement of health in the sturdy men, because regular exercise suppresses body fat and obesity-related factors. PMID:24278869

  19. Structural modulation of the gut microbiota and the relationship with body weight: compared evaluation of liraglutide and saxagliptin treatment

    PubMed Central

    Wang, Lin; Li, Peicheng; Tang, Zhaosheng; Yan, Xinfeng; Feng, Bo

    2016-01-01

    The mechanisms underlying the weight-loss effect of GLP-1 receptor agonists need further elucidation. The present study was performed to explore the effects of liraglutide and saxagliptin on the composition of the gut microbiota. Mice were randomly treated with saxagliptin or liraglutide for eight weeks. Their metabolic profiles were assessed, and 454 pyrosequencing of 16s rRNA of faeces was performed. Liraglutide induced a smaller body weight gain in mice. The pyrosequencing showed that liraglutide, but not saxagliptin, substantially changed the overall structure of the gut microbiota as well as the relative abundance of weight-relevant phylotypes. Subsequent ridge regression analyses indicated that, in addition to food intake (β = −0.182, p = 0.043 in phylotypes inversely correlated with body weight) and blood glucose level (β = −0.240, p = 0.039 in phylotypes positively correlated with body weight), the administration of liraglutide was another independent factor associated with the abundance of weight-relevant phylotypes (β = 0.389, p = 6.24e-5 in inversely correlated ones; β = −0.508, p = 2.25e-5 in positively correlated ones). These results evidenced that GLP-1 receptor agonist liraglutide could modulate the composition of the gut microbiota, leading to a more lean-related profile that was consistent with its weight-losing effect. PMID:27633081

  20. Integration of detailed modules in a core model of body fluid homeostasis and blood pressure regulation.

    PubMed

    Hernández, Alfredo I; Le Rolle, Virginie; Ojeda, David; Baconnier, Pierre; Fontecave-Jallon, Julie; Guillaud, François; Grosse, Thibault; Moss, Robert G; Hannaert, Patrick; Thomas, S Randall

    2011-10-01

    This paper presents a contribution to the definition of the interfaces required to perform heterogeneous model integration in the context of integrative physiology. A formalization of the model integration problem is proposed and a coupling method is presented. The extension of the classic Guyton model, a multi-organ, integrated systems model of blood pressure regulation, is used as an example of the application of the proposed method. To this end, the Guyton model has been restructured, extensive sensitivity analyses have been performed, and appropriate transformations have been applied to replace a subset of its constituting modules by integrating a pulsatile heart and an updated representation of the renin-angiotensin system. Simulation results of the extended integrated model are presented and the impacts of their integration within the original model are evaluated.

  1. Dosimetric Impact of Breathing Motion in Lung Stereotactic Body Radiotherapy Treatment Using Image-Modulated Radiotherapy and Volumetric Modulated Arc Therapy

    SciTech Connect

    Rao Min; Wu Jianzhou; Cao Daliang; Wong, Tony; Mehta, Vivek; Shepard, David; Ye Jinsong

    2012-06-01

    Purpose: The objective of this study was to investigate the influence of tumor motion on dose delivery in stereotactic body radiotherapy (SBRT) for lung cancer, using fixed field intensity- modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT). Methods and Materials: For each of 10 patients with stage I/II non-small-cell pulmonary tumors, a respiration-correlated four-dimensional computed tomography (4DCT) study was carried out. The internal target volume was delineated on the maximum intensity projection CT, which was reconstructed from the 4DCT dataset. A 5-mm margin was used for generation of the planning target volume. VMAT and five-field IMRT plans were generated using Pinnacle{sup 3} SmartArc and direct machine parameter optimization, respectively. All plans were generated for an Elekta Synergy linear accelerator using 6-MV photons. Simulation was performed to study the interplay between multileaf collimator (MLC) sequences and target movement during the delivery of VMAT and IMRT. For each plan, 4D dose was calculated using deformable image registration of the 4DCT images. Target volume coverage and doses to critical structures calculated using 4D methodology were compared with those calculated using 3D methodology. Results: For all patients included in this study, the interplay effect was found to present limited impact (less than 1% of prescription) on the target dose distribution, especially for SBRT, in which fewer fractions (three fractions) are delivered. Dose to the gross tumor volume (GTV) was, on average, slightly decreased (1% of prescription) in the 4D calculation compared with the 3D calculation. The motion impact on target dose homogeneity was patient-dependent and relatively small. Conclusions: Both VMAT and IMRT plans experienced negligible interplay effects between MLC sequence and tumor motion. For the most part, the 3D doses to the GTV and critical structures provided good approximations of the 4D dose calculations.

  2. Simple neural substrate predicts complex rhythmic structure in duetting birds

    NASA Astrophysics Data System (ADS)

    Amador, Ana; Trevisan, M. A.; Mindlin, G. B.

    2005-09-01

    Horneros (Furnarius Rufus) are South American birds well known for their oven-looking nests and their ability to sing in couples. Previous work has analyzed the rhythmic organization of the duets, unveiling a mathematical structure behind the songs. In this work we analyze in detail an extended database of duets. The rhythms of the songs are compatible with the dynamics presented by a wide class of dynamical systems: forced excitable systems. Compatible with this nonlinear rule, we build a biologically inspired model for how the neural and the anatomical elements may interact to produce the observed rhythmic patterns. This model allows us to synthesize songs presenting the acoustic and rhythmic features observed in real songs. We also make testable predictions in order to support our hypothesis.

  3. E2FBP1/hDril1 modulates cell growth through downregulation of promyelocytic leukemia bodies.

    PubMed

    Fukuyo, Y; Mogi, K; Tsunematsu, Y; Nakajima, T

    2004-07-01

    Promyelocytic leukemia nuclear bodies (PML-NBs) comprise multiple regulatory factors and play crucial roles in the maintenance of cellular integrity, while unregulated activation of PML-NBs induces death and premature senescence. Hence, the function of PML-NBs must be directed properly; however, the mechanism that regulates PML-NBs remains unclear. In this paper, we show that PML-NBs are disintegrated by an AT-rich interaction domain family protein E2FBP1/hDril1 through specific desumoylation of promyelocytic leukemia protein (PML) in vivo and in vitro. RNA interference-mediated downregulation of E2FBP1/hDril1 results in hyperplasis of PML-NBs and consequent commitment to PML-dependent premature senescence. Thus, the function of E2FBP1/hDril1 is required for maintenance of survival potential of the cells. Our data suggest a novel mechanism to govern cellular integrity through the modulation of nuclear depots.

  4. Nutritional modulation of IGF-1 in relation to growth and body condition in Sceloporus lizards.

    PubMed

    Duncan, Christine A; Jetzt, Amanda E; Cohick, Wendie S; John-Alder, Henry B

    2015-05-15

    Nutrition and energy balance are important regulators of growth and the growth hormone/insulin-like growth factor (GH/IGF) axis. However, our understanding of these functions does not extend uniformly to all classes of vertebrates and is mainly limited to controlled laboratory conditions. Lizards can be useful models to improve our understanding of the nutritional regulation of the GH/IGF-1 axis because many species are relatively easy to observe and manipulate both in the laboratory and in the field. In the present study, the effects of variation in food intake on growth, body condition, and hepatic IGF-1 mRNA levels were measured in (1) juveniles of Sceloporus jarrovii maintained on a full or 1/3 ration and (2) hatchlings of Sceloporus undulatus subjected to full or zero ration with or without re-feeding. These parameters plus plasma IGF-1 were measured in a third experiment using adults of S. undulatus subjected to full or zero ration with or without re-feeding. In all experiments, plasma corticosterone was measured as an anticipated indicator of nutritional stress. In S. jarrovii, growth and body condition were reduced but lizards remained in positive energy balance on 1/3 ration, and hepatic IGF-1 mRNA and plasma corticosterone were not affected in comparison to full ration. In S. undulatus, growth, body condition, hepatic IGF-1 mRNA, and plasma IGF-1 were all reduced by zero ration and restored by refeeding. Plasma corticosterone was increased in response to zero ration and restored by full ration in hatchlings but not adults of S. undulatus. These data indicate that lizards conform to the broader vertebrate model in which severe food deprivation and negative energy balance is required to attenuate systemic IGF-1 expression. However, when animals remain in positive energy balance, reduced food intake does not appear to affect systemic IGF-1. Consistent with other studies on lizards, the corticosterone response to reduced food intake is an unreliable indicator

  5. Chemotransduction in the Carotid Body: K+ Current Modulated by Po2 in Type I Chemoreceptor Cells

    NASA Astrophysics Data System (ADS)

    Lopez-Barneo, Jose; Lopez-Lopez, Jose R.; Urena, Juan; Gonzalez, Constancio

    1988-07-01

    The ionic currents of carotid body type I cells and their possible involvement in the detection of oxygen tension (Po2) in arterial blood are unknown. The electrical properties of these cells were studied with the whole-cell patch clamp technique, and the hypothesis that ionic conductances can be altered by changes in Po2 was tested. The results show that type I cells have voltage-dependent sodium, calcium, and potassium channels. Sodium and calcium currents were unaffected by a decrease in Po2 from 150 to 10 millimeters of mercury, whereas, with the same experimental protocol, potassium currents were reversibly reduced by 25 to 50 percent. The effect of hypoxia was independent of internal adenosine triphosphate and calcium. Thus, ionic conductances, and particularly the O2-sensitive potassium current, play a key role in the transduction mechanism of arterial chemoreceptors.

  6. Low-dose total-body γ irradiation modulates immune response to acute proton radiation.

    PubMed

    Luo-Owen, Xian; Pecaut, Michael J; Rizvi, Asma; Gridley, Daila S

    2012-03-01

    Health risks due to exposure to low-dose/low-dose-rate radiation alone or when combined with acute irradiation are not yet clearly defined. This study quantified the effects of protracted exposure to low-dose/low-dose-rate γ rays with and without acute exposure to protons on the response of immune and other cell populations. C57BL/6 mice were irradiated with ⁵⁷Co (0.05 Gy at 0.025 cGy/h); subsets were subsequently exposed to high-dose/high-dose-rate proton radiation (250 MeV; 2 or 3 Gy at 0.5 Gy/min). Analyses were performed at 4 and 17 days postexposure. Spleen and thymus masses relative to body mass were decreased on day 4 after proton irradiation with or without pre-exposure to γ rays; by day 17, however, the decrease was attenuated by the priming dose. Proton dose-dependent decreases, either with or without pre-exposure to γ rays, occurred in white blood cell, lymphocyte and granulocyte counts in blood but not in spleen. A similar pattern was found for lymphocyte subpopulations, including CD3+ T, CD19+ B, CD4+ T, CD8+ T and NK1.1+ natural killer (NK) cells. Spontaneous DNA synthesis by leukocytes after proton irradiation was high in blood on day 4 and high in spleen on day 17; priming with γ radiation attenuated the effect of 3 Gy in both body compartments. Some differences were also noted among groups in erythrocyte and thrombocyte characteristics. Analysis of splenocytes activated with anti-CD3/anti-CD28 antibodies showed changes in T-helper 1 (Th1) and Th2 cytokines. Overall, the data demonstrate that pre-exposure of an intact mammal to low-dose/low-dose-rate γ rays can attenuate the response to acute exposure to proton radiation with respect to at least some cell populations.

  7. Can dancers suppress the haptically mediated interpersonal entrainment during rhythmic sway?

    PubMed

    Sofianidis, George; Elliott, Mark T; Wing, Alan M; Hatzitaki, Vassilia

    2014-07-01

    Interpersonal entrainment emerges spontaneously when partners performing rhythmic movements together exchange sensory feedback about the other's movements. In this study, we asked whether couples of expert dancers, non-dancers and mixed couples can suppress the spontaneous haptically mediated inter-personal entrainment when their rhythmic sway is paced by differing metronome tempos. Fifty-four young participants formed three types of couples: nine dancer couples, consisting of individuals with at least eight years systematic practice in traditional Greek dance; nine non-dancer couples, consisting of individuals with no prior experience in dance and nine mixed couples, consisting of one dancer and one novice partner. Partners swayed rhythmically for 60 s, at different pacing frequencies (one at 0.25 Hz and the other at 0.35 Hz) under three haptic contact conditions: no contact between them; light fingertip touch established in the 2nd trial segment (30 s); and light fingertip touch released in the 2nd trial segment (30 s). Spectral analysis of the antero-posterior center of pressure displacement revealed that light touch increased the deviation of the dominant from the target (pacing) sway frequency, decreased the proportion of the signal's power at the target frequency and increased the coherence between the partners' sway signals (inter-personal coherence). These effects were specific to the mixed group whereas touch interference was weaker in non-dancers and absent in dancers. In addition, the coherence between the trial segments (intra-personal coherence) significantly decreased with touch only for the non-dancer while it remained unchanged for the dancer partner of the mixed group suggesting that the dancer was leading the non-dancer partner. It is concluded that systematic practice with traditional dance can modulate the spontaneous tendency towards haptically mediated interpersonal entrainment.

  8. The presence of pacemaker HCN channels identifies theta rhythmic GABAergic neurons in the medial septum.

    PubMed

    Varga, Viktor; Hangya, Balázs; Kránitz, Kinga; Ludányi, Anikó; Zemankovics, Rita; Katona, István; Shigemoto, Ryuichi; Freund, Tamás F; Borhegyi, Zsolt

    2008-08-15

    The medial septum (MS) is an indispensable component of the subcortical network which synchronizes the hippocampus at theta frequency during specific stages of information processing. GABAergic neurons exhibiting highly regular firing coupled to the hippocampal theta rhythm are thought to form the core of the MS rhythm-generating network. In recent studies the hyperpolarization-activated, cyclic nucleotide-gated non-selective cation (HCN) channel was shown to participate in theta synchronization of the medial septum. Here, we tested the hypothesis that HCN channel expression correlates with theta modulated firing behaviour of MS neurons by a combined anatomical and electrophysiological approach. HCN-expressing neurons represented a subpopulation of GABAergic cells in the MS partly overlapping with parvalbumin (PV)-containing neurons. Rhythmic firing in the theta frequency range was characteristic of all HCN-expressing neurons. In contrast, only a minority of HCN-negative cells displayed theta related activity. All HCN cells had tight phase coupling to hippocampal theta waves. As a group, PV-expressing HCN neurons had a marked bimodal phase distribution, whereas PV-immunonegative HCN neurons did not show group-level phase preference despite significant individual phase coupling. Microiontophoretic blockade of HCN channels resulted in the reduction of discharge frequency, but theta rhythmic firing was perturbed only in a few cases. Our data imply that HCN-expressing GABAergic neurons provide rhythmic drive in all phases of the hippocampal theta activity. In most MS theta cells rhythm genesis is apparently determined by interactions at the level of the network rather than by the pacemaking property of HCN channels alone.

  9. Rhythmic Effects of Syntax Processing in Music and Language.

    PubMed

    Jung, Harim; Sontag, Samuel; Park, YeBin S; Loui, Psyche

    2015-01-01

    Music and language are human cognitive and neural functions that share many structural similarities. Past theories posit a sharing of neural resources between syntax processing in music and language (Patel, 2003), and a dynamic attention network that governs general temporal processing (Large and Jones, 1999). Both make predictions about music and language processing over time. Experiment 1 of this study investigates the relationship between rhythmic expectancy and musical and linguistic syntax in a reading time paradigm. Stimuli (adapted from Slevc et al., 2009) were sentences broken down into segments; each sentence segment was paired with a musical chord and presented at a fixed inter-onset interval. Linguistic syntax violations appeared in a garden-path design. During the critical region of the garden-path sentence, i.e., the particular segment in which the syntactic unexpectedness was processed, expectancy violations for language, music, and rhythm were each independently manipulated: musical expectation was manipulated by presenting out-of-key chords and rhythmic expectancy was manipulated by perturbing the fixed inter-onset interval such that the sentence segments and musical chords appeared either early or late. Reading times were recorded for each sentence segment and compared for linguistic, musical, and rhythmic expectancy. Results showed main effects of rhythmic expectancy and linguistic syntax expectancy on reading time. There was also an effect of rhythm on the interaction between musical and linguistic syntax: effects of violations in musical and linguistic syntax showed significant interaction only during rhythmically expected trials. To test the effects of our experimental design on rhythmic and linguistic expectancies, independently of musical syntax, Experiment 2 used the same experimental paradigm, but the musical factor was eliminated-linguistic stimuli were simply presented silently, and rhythmic expectancy was manipulated at the critical

  10. Rhythmic Effects of Syntax Processing in Music and Language

    PubMed Central

    Jung, Harim; Sontag, Samuel; Park, YeBin S.; Loui, Psyche

    2015-01-01

    Music and language are human cognitive and neural functions that share many structural similarities. Past theories posit a sharing of neural resources between syntax processing in music and language (Patel, 2003), and a dynamic attention network that governs general temporal processing (Large and Jones, 1999). Both make predictions about music and language processing over time. Experiment 1 of this study investigates the relationship between rhythmic expectancy and musical and linguistic syntax in a reading time paradigm. Stimuli (adapted from Slevc et al., 2009) were sentences broken down into segments; each sentence segment was paired with a musical chord and presented at a fixed inter-onset interval. Linguistic syntax violations appeared in a garden-path design. During the critical region of the garden-path sentence, i.e., the particular segment in which the syntactic unexpectedness was processed, expectancy violations for language, music, and rhythm were each independently manipulated: musical expectation was manipulated by presenting out-of-key chords and rhythmic expectancy was manipulated by perturbing the fixed inter-onset interval such that the sentence segments and musical chords appeared either early or late. Reading times were recorded for each sentence segment and compared for linguistic, musical, and rhythmic expectancy. Results showed main effects of rhythmic expectancy and linguistic syntax expectancy on reading time. There was also an effect of rhythm on the interaction between musical and linguistic syntax: effects of violations in musical and linguistic syntax showed significant interaction only during rhythmically expected trials. To test the effects of our experimental design on rhythmic and linguistic expectancies, independently of musical syntax, Experiment 2 used the same experimental paradigm, but the musical factor was eliminated—linguistic stimuli were simply presented silently, and rhythmic expectancy was manipulated at the critical

  11. Effects of sympathetic stimulation on the rhythmical jaw movements produced by electrical stimulation of the cortical masticatory areas of rabbits.

    PubMed

    Roatta, S; Windhorst, U; Djupsjöbacka, M; Lytvynenko, S; Passatore, M

    2005-03-01

    The somatomotor and sympathetic nervous systems are intimately linked. One example is the influence of peripheral sympathetic fibers on the discharge characteristics of muscle spindles. Since muscle spindles play important roles in various motor behaviors, including rhythmic movements, the working hypothesis of this research was that changes in sympathetic outflow to muscle spindles can change rhythmic movement patterns. We tested this hypothesis in the masticatory system of rabbits. Rhythmic jaw movements and EMG activity induced by long-lasting electrical cortical stimulation were powerfully modulated by electrical stimulation of the peripheral stump of the cervical sympathetic nerve (CSN). This modulation manifested itself as a consistent and marked reduction in the excursion of the mandibular movements (often preceded by a transient modest enhancement), which could be attributed mainly to corresponding changes in masseter muscle activity. These changes outlasted the duration of CSN stimulation. In some of the cortically evoked rhythmic jaw movements (CRJMs) changes in masticatory frequency were also observed. When the jaw-closing muscles were subjected to repetitive ramp-and-hold force pulses, the CRMJs changed characteristics. Masseter EMG activity was strongly enhanced and digastric EMG slightly decreased. This change was considerably depressed during CSN stimulation. These effects of CSN stimulation are similar in sign and time course to the depression exerted by sympathetic activity on the jaw-closing muscle spindle discharge. It is suggested that the change in proprioceptive information induced by an increase in sympathetic outflow (a) has important implications even under normal conditions for the control of motor function in states of high sympathetic activity, and (b) is one of the mechanisms responsible for motor impairment under certain pathological conditions such as chronic musculoskeletal head-neck disorders, associated with stress conditions.

  12. Long-Term Outcome After Static Intensity-Modulated Total Body Radiotherapy Using Compensators Stratified by Pediatric and Adult Cohorts

    SciTech Connect

    Schneider, Ralf A. Schultze, Juergen; Jensen, J. Martin; Hebbinghaus, Dieter; Galalae, Razvan M.

    2008-01-01

    Purpose: To report the long-term outcome after total body irradiation with intensity-modulating compensators and allogeneic/autologous transplantation, especially in terms of therapy-related toxicity in pediatric and adult cohorts. Methods and Materials: A total of 257 consecutive patients (40 children and 217 adults) have been treated since 1983 with TBI using static intensity-modulated radiotherapy for hematologic malignancies. The total dose of 12 Gy was applied in six fractions within 3 days before allogeneic (n = 174) or autologous (n = 83) transplantation. The median follow-up was 9.2 years. Results: The 5-year overall survival rate was 47.9% (49.8% for the adults and 37.5% for the children, p = 0.171). The 5-year tumor-related mortality rate was 23%, and the 5-year treatment-related mortality rate 29.2% (29.5% in the adults and 27.5% in the pediatric patients). Interstitial pneumonitis developed in 28 (10.9%) of 257 patients and in 12.5% of the pediatric cohort. The interstitial pneumonitis rate was 25% in pediatric patients treated with a 12-Gy lung dose compared with 4.2% for those treated to an 11-Gy lung dose. The overall survival rate stratified by lung dose was 26.7% for 12 Gy and 52.4% for 11 Gy (p = 0.001). The incidence of veno-occlusive disease and cataract was 5.8% and 6.6% in all patients and 12.5% and 15% in the pediatric patients, respectively (p < 0.05). Secondary malignancies were found in 4.3% of all patients, all in the adult cohort at transplantation. Conclusion: Static intensity-modulated total body irradiation with a total dose of 12 Gy before allogeneic/autologous transplantation is a successful treatment with good long-term outcome and acceptable therapy-related toxicities. Constraining the lung dose to 11 Gy substantially lowered the actuarial treatment-related mortality. This effect was especially striking in the pediatric patients.

  13. MKS and NPHP modules cooperate to establish basal body/transition zone membrane associations and ciliary gate function during ciliogenesis

    PubMed Central

    Williams, Corey L.; Kida, Katarzyna; Inglis, Peter N.; Mohan, Swetha; Semenec, Lucie; Bialas, Nathan J.; Stupay, Rachel M.; Chen, Nansheng

    2011-01-01

    Meckel-Gruber syndrome (MKS), nephronophthisis (NPHP), and related ciliopathies present with overlapping phenotypes and display considerable allelism between at least twelve different genes of largely unexplained function. We demonstrate that the conserved C. elegans B9 domain (MKS-1, MKSR-1, and MKSR-2), MKS-3/TMEM67, MKS-5/RPGRIP1L, MKS-6/CC2D2A, NPHP-1, and NPHP-4 proteins exhibit essential, collective functions at the transition zone (TZ), an underappreciated region at the base of all cilia characterized by Y-shaped assemblages that link axoneme microtubules to surrounding membrane. These TZ proteins functionally interact as members of two distinct modules, which together contribute to an early ciliogenic event. Specifically, MKS/MKSR/NPHP proteins establish basal body/TZ membrane attachments before or coinciding with intraflagellar transport–dependent axoneme extension and subsequently restrict accumulation of nonciliary components within the ciliary compartment. Together, our findings uncover a unified role for eight TZ-localized proteins in basal body anchoring and establishing a ciliary gate during ciliogenesis, and suggest that disrupting ciliary gate function contributes to phenotypic features of the MKS/NPHP disease spectrum. PMID:21422230

  14. Salvage image-guided intensity modulated or stereotactic body reirradiation of local recurrence of prostate cancer

    PubMed Central

    Jereczek-Fossa, B A; Fodor, C; Bazzani, F; Maucieri, A; Ronchi, S; Ferrario, S; Colangione, S P; Gerardi, M A; Caputo, M; Cecconi, A; Gherardi, F; Vavassori, A; Comi, S; Cambria, R; Garibaldi, C; Cattani, F; De Cobelli, O; Orecchia, R

    2015-01-01

    Objective: To retrospectively evaluate external beam reirradiation (re-EBRT) delivered to the prostate/prostatic bed for local recurrence, after radical or adjuvant/salvage radiotherapy (RT). Methods: 32 patients received re-EBRT between February 2008 and October 2013. All patients had clinical/radiological local relapse in the prostate or prostatic bed and no distant metastasis. re-EBRT was delivered with selective RT technologies [stereotactic RT including CyberKnifeTM (Accuray, Sunnyvale, CA); image-guidance and intensity-modulated RT etc.]. Toxicity was evaluated using the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria. Biochemical control was assessed according to the Phoenix definition (NADIR + 2 ng ml−1). Results: Acute urinary toxicity: G0, 24 patients; G1, 6 patients; G2, 2 patients. Acute rectal toxicity: G0, 28 patients; G1, 2 patients; and G2, 1 patient. Late urinary toxicity (evaluated in 30 cases): G0, 23 patients; G1, 6 patients; G2, 1 patient. Late renal toxicity: G0, 25 patients; G1, 5 patients. A mean follow-up of 21.3 months after re-EBRT showed that 13 patients were free of cancer, 3 were alive with biochemical relapse and 12 patients were alive with clinically evident disease. Four patients had died: two of disease progression and two of other causes. Conclusion: re-EBRT using modern technology is a feasible approach for local prostate cancer recurrence offering 2-year tumour control in about half of the patients. Toxicity of re-EBRT is low. Future studies are needed to identify the patients who would benefit most from this treatment. Advances in knowledge: Our series, based on experience in one hospital alone, shows that re-EBRT for local relapse of prostate cancer is feasible and offers a 2-year cure in about half of the patients. PMID:26055506

  15. Affect differentially modulates brain activation in uni- and multisensory body-voice perception.

    PubMed

    Jessen, Sarah; Kotz, Sonja A

    2015-01-01

    Emotion perception naturally entails multisensory integration. It is also assumed that multisensory emotion perception is characterized by enhanced activation of brain areas implied in multisensory integration, such as the superior temporal gyrus and sulcus (STG/STS). However, most previous studies have employed designs and stimuli that preclude other forms of multisensory interaction, such as crossmodal prediction, leaving open the question whether classical integration is the only relevant process in multisensory emotion perception. Here, we used video clips containing emotional and neutral body and vocal expressions to investigate the role of crossmodal prediction in multisensory emotion perception. While emotional multisensory expressions increased activation in the bilateral fusiform gyrus (FFG), neutral expressions compared to emotional ones enhanced activation in the bilateral middle temporal gyrus (MTG) and posterior STS. Hence, while neutral stimuli activate classical multisensory areas, emotional stimuli invoke areas linked to unisensory visual processing. Emotional stimuli may therefore trigger a prediction of upcoming auditory information based on prior visual information. Such prediction may be stronger for highly salient emotional compared to less salient neutral information. Therefore, we suggest that multisensory emotion perception involves at least two distinct mechanisms; classical multisensory integration, as shown for neutral expressions, and crossmodal prediction, as evident for emotional expressions.

  16. RESEMBLANCES BETWEEN THE ELECTROMOTOR VARIATIONS OF RHYTHMICALLY REACTING LIVING AND NON-LIVING SYSTEMS.

    PubMed

    Lillie, R S

    1929-09-20

    1. The electromotor variations of pure iron wires, arranged to react rhythmically with nitric acid, are recorded and described. 2. Resemblances between these variations and those of rhythmically reacting living tissues (especially the heart) are pointed out and discussed.

  17. The origin of rhythmic layering in the Cape Neddick Plutonic Complex, Maine

    SciTech Connect

    Shipley, J. . Dept. of Geology)

    1993-03-01

    The Cape Neddick Plutonic Complex located along the southwestern coast of Maine is a small layered gabbroic body. It contains four concentric gabbros of differing composition, From the center to the exterior these are Cortlandtitic, Anorthositic, Normal, and Pegmatitic gabbros. They vary slightly in the proportion of essential minerals; plagioclase, clinopyroxene, hornblende, and biotite [+-] opaques and olivine. Rhythmic layering is seen in all four gabbros. This layering is also concentric around the center of the complex. The best exposure of the layering is along the coast where non-graded and graded rhythmic layering is seen extensively in the Normal gabbro. Only non-graded layering is seen in the Anorthositic gabbro. Non-graded layers were sampled at two localities. One locality is on Cape Nubble Island in the Normal gabbro. The second locality is in the Anorthositic gabbro along the northern coast. The layers are roughly 5--8 cm in width and are continuous around the complex. They are identified on weathered surfaces as alternating bands of felsic and mafic minerals. Layers are not obvious in hand sample. Approximately 15--20 layers were sampled perpendicular to layering. Petrographic and geochemical studies will help constrain the origin of rhythmic layering in the Cape Neddick Complex. Crystal settling or structural processes seem highly unlikely due to the small distance between the layers and the fact that they are not graded. Possible models include multiple pulses of magma within the same magma chamber, density currents, or in situ fractionation by a nucleation-diffusion process. Modal and chemical analysis of mineral phases within individual layers will allow comparison of the bulk composition of each layer. Analysis of coexisting pyroxene and plagioclase can be used to estimate compositional variations in the parent liquid.

  18. What is orgasm? A model of sexual trance and climax via rhythmic entrainment

    PubMed Central

    Safron, Adam

    2016-01-01

    Orgasm is one of the most intense pleasures attainable to an organism, yet its underlying mechanisms remain poorly understood. On the basis of existing literatures, this article introduces a novel mechanistic model of sexual stimulation and orgasm. In doing so, it characterizes the neurophenomenology of sexual trance and climax, describes parallels in dynamics between orgasms and seizures, speculates on possible evolutionary origins of sex differences in orgasmic responding, and proposes avenues for future experimentation. Here, a model is introduced wherein sexual stimulation induces entrainment of coupling mechanical and neuronal oscillatory systems, thus creating synchronized functional networks within which multiple positive feedback processes intersect synergistically to contribute to sexual experience. These processes generate states of deepening sensory absorption and trance, potentially culminating in climax if critical thresholds are surpassed. The centrality of rhythmic stimulation (and its modulation by salience) for surpassing these thresholds suggests ways in which differential orgasmic responding between individuals—or with different partners—may serve as a mechanism for ensuring adaptive mate choice. Because the production of rhythmic stimulation combines honest indicators of fitness with cues relating to potential for investment, differential orgasmic response may serve to influence the probability of continued sexual encounters with specific mates. PMID:27799079

  19. The PXDLS linear motif regulates circadian rhythmicity through protein–protein interactions

    PubMed Central

    Shalev, Moran; Aviram, Rona; Adamovich, Yaarit; Kraut-Cohen, Judith; Shamia, Tal; Ben-Dor, Shifra; Golik, Marina; Asher, Gad

    2014-01-01

    The circadian core clock circuitry relies on interlocked transcription-translation feedback loops that largely count on multiple protein interactions. The molecular mechanisms implicated in the assembly of these protein complexes are relatively unknown. Our bioinformatics analysis of short linear motifs, implicated in protein interactions, reveals an enrichment of the Pro-X-Asp-Leu-Ser (PXDLS) motif within circadian transcripts. We show that the PXDLS motif can bind to BMAL1/CLOCK and disrupt circadian oscillations in a cell-autonomous manner. Remarkably, the motif is evolutionary conserved in the core clock protein REV-ERBα, and additional proteins implicated in the clock's function (NRIP1, CBP). In this conjuncture, we uncover a novel cross talk between the two principal core clock feedback loops and show that BMAL/CLOCK and REV-ERBα interact and that the PXDLS motif of REV-ERBα participates in their binding. Furthermore, we demonstrate that the PXDLS motifs of NRIP1 and CBP are involved in circadian rhythmicity. Our findings suggest that the PXDLS motif plays an important role in circadian rhythmicity through regulation of protein interactions within the clock circuitry and that short linear motifs can be employed to modulate circadian oscillations. PMID:25260595

  20. What is orgasm? A model of sexual trance and climax via rhythmic entrainment.

    PubMed

    Safron, Adam

    2016-01-01

    Orgasm is one of the most intense pleasures attainable to an organism, yet its underlying mechanisms remain poorly understood. On the basis of existing literatures, this article introduces a novel mechanistic model of sexual stimulation and orgasm. In doing so, it characterizes the neurophenomenology of sexual trance and climax, describes parallels in dynamics between orgasms and seizures, speculates on possible evolutionary origins of sex differences in orgasmic responding, and proposes avenues for future experimentation. Here, a model is introduced wherein sexual stimulation induces entrainment of coupling mechanical and neuronal oscillatory systems, thus creating synchronized functional networks within which multiple positive feedback processes intersect synergistically to contribute to sexual experience. These processes generate states of deepening sensory absorption and trance, potentially culminating in climax if critical thresholds are surpassed. The centrality of rhythmic stimulation (and its modulation by salience) for surpassing these thresholds suggests ways in which differential orgasmic responding between individuals-or with different partners-may serve as a mechanism for ensuring adaptive mate choice. Because the production of rhythmic stimulation combines honest indicators of fitness with cues relating to potential for investment, differential orgasmic response may serve to influence the probability of continued sexual encounters with specific mates.

  1. Influence of Ionic Conductances on Spike Timing Reliability of Cortical Neurons for Suprathreshold Rhythmic Inputs

    PubMed Central

    Schreiber, Susanne; Fellous, Jean-Marc; Tiesinga, Paul; Sejnowski, Terrence J.

    2010-01-01

    Spike timing reliability of neuronal responses depends on the frequency content of the input. We investigate how intrinsic properties of cortical neurons affect spike timing reliability in response to rhythmic inputs of suprathreshold mean. Analyzing reliability of conductance-based cortical model neurons on the basis of a correlation measure, we show two aspects of how ionic conductances influence spike timing reliability. First, they set the preferred frequency for spike timing reliability, which in accordance with the resonance effect of spike timing reliability is well approximated by the firing rate of a neuron in response to the DC component in the input. We demonstrate that a slow potassium current can modulate the spike timing frequency preference over a broad range of frequencies. This result is confirmed experimentally by dynamic-clamp recordings from rat prefrontal cortical neurons in vitro. Second, we provide evidence that ionic conductances also influence spike timing beyond changes in preferred frequency. Cells with the same DC firing rate exhibit more reliable spike timing at the preferred frequency and its harmonics if the slow potassium current is larger and its kinetics are faster, whereas a larger persistent sodium current impairs reliability. We predict that potassium channels are an efficient target for neuromodulators that can tune spike timing reliability to a given rhythmic input. PMID:14507985

  2. Perceptual Tests of Rhythmic Similarity: II. Syllable Rhythm

    ERIC Educational Resources Information Center

    Kim, Jeesun; Davis, Chris; Cutler, Anne

    2008-01-01

    To segment continuous speech into its component words, listeners make use of language rhythm; because rhythm differs across languages, so do the segmentation procedures which listeners use. For each of stress-, syllable-and mora-based rhythmic structure, perceptual experiments have led to the discovery of corresponding segmentation procedures. In…

  3. Perceptual Tests of Rhythmic Similarity: I. Mora Rhythm

    ERIC Educational Resources Information Center

    Murty, Lalita; Otake, Takashi; Cutler, Anne

    2007-01-01

    Listeners rely on native-language rhythm in segmenting speech; in different languages, stress-, syllable- or mora-based rhythm is exploited. The rhythmic similarity hypothesis holds that where two languages have similar rhythm, listeners of each language should segment their own and the other language similarly. Such similarity in listening was…

  4. Effects of Kindermusik Training on Infants' Rhythmic Enculturation

    ERIC Educational Resources Information Center

    Gerry, David W.; Faux, Ashley L.; Trainor, Laurel J.

    2010-01-01

    Phillips-Silver and Trainor (2005) demonstrated a link between movement and the metrical interpretation of rhythm patterns in 7-month-old infants. Infants bounced on every second beat of a rhythmic pattern with no auditory accents later preferred to listen to an accented version of the pattern with accents every second beat (duple or march meter),…

  5. Precompetition warm-up in elite and subelite rhythmic gymnastics.

    PubMed

    Guidetti, Laura; Di Cagno, Alessandra; Gallotta, Maria Chiara; Battaglia, Claudia; Piazza, Marina; Baldari, Carlo

    2009-09-01

    The aim of this study was to investigate which precompetition warm-up methodologies resulted in the best overall performance in rhythmic gymnastics. The coaches of national and international clubs (60 elite and 90 subelite) were interviewed. The relationship between sport performance and precompetition warm-up routines was examined. A total of 49% of the coaches interviewed spent more than 1 hour to prepare their athletes for the competition, including 45 minutes dedicated to warm-up exercises. In spite of previous studies' suggestions, the time between the end of warm-up and the beginning of competition was more than 5 minutes for 68% of those interviewed. A slow run was the activity of choice used to begin the warm-up (96%). Significant differences between elite and subelite gymnasts were found concerning the total duration of warm-up, duration of slow running, utilization of rhythmic steps and leaps during the warm-up, the use of dynamic flexibility exercises, competition performances repetition (p < 0.01), and utilization of imagery (p < 0.05). A precompetition warm-up in rhythmic gymnastics would include static stretching exercises at least 60 minutes prior to the competition starting time and the active stretching exercises alternated with analytic muscle strengthening aimed at increasing muscle temperature. Rhythmic gymnastics coaches at all levels can use this data as a review of precompetition warm-up practices and a possible source of new ideas.

  6. Cross-Linguistic Comparison of Rhythmic and Phonotactic Similarity

    ERIC Educational Resources Information Center

    Stojanovic, Diana

    2013-01-01

    Literature on speech rhythm has been focused on three major questions: whether languages have rhythms that can be classified into a small number of types, what the criteria are for the membership in each class, and whether the perceived rhythmic similarity between languages can be quantified based on properties found in the speech signal. Claims…

  7. Evolution of central pattern generators and rhythmic behaviours

    PubMed Central

    Katz, Paul S.

    2016-01-01

    Comparisons of rhythmic movements and the central pattern generators (CPGs) that control them uncover principles about the evolution of behaviour and neural circuits. Over the course of evolutionary history, gradual evolution of behaviours and their neural circuitry within any lineage of animals has been a predominant occurrence. Small changes in gene regulation can lead to divergence of circuit organization and corresponding changes in behaviour. However, some behavioural divergence has resulted from large-scale rewiring of the neural network. Divergence of CPG circuits has also occurred without a corresponding change in behaviour. When analogous rhythmic behaviours have evolved independently, it has generally been with different neural mechanisms. Repeated evolution of particular rhythmic behaviours has occurred within some lineages due to parallel evolution or latent CPGs. Particular motor pattern generating mechanisms have also evolved independently in separate lineages. The evolution of CPGs and rhythmic behaviours shows that although most behaviours and neural circuits are highly conserved, the nature of the behaviour does not dictate the neural mechanism and that the presence of homologous neural components does not determine the behaviour. This suggests that although behaviour is generated by neural circuits, natural selection can act separately on these two levels of biological organization. PMID:26598733

  8. Evolution of central pattern generators and rhythmic behaviours.

    PubMed

    Katz, Paul S

    2016-01-05

    Comparisons of rhythmic movements and the central pattern generators (CPGs) that control them uncover principles about the evolution of behaviour and neural circuits. Over the course of evolutionary history, gradual evolution of behaviours and their neural circuitry within any lineage of animals has been a predominant occurrence. Small changes in gene regulation can lead to divergence of circuit organization and corresponding changes in behaviour. However, some behavioural divergence has resulted from large-scale rewiring of the neural network. Divergence of CPG circuits has also occurred without a corresponding change in behaviour. When analogous rhythmic behaviours have evolved independently, it has generally been with different neural mechanisms. Repeated evolution of particular rhythmic behaviours has occurred within some lineages due to parallel evolution or latent CPGs. Particular motor pattern generating mechanisms have also evolved independently in separate lineages. The evolution of CPGs and rhythmic behaviours shows that although most behaviours and neural circuits are highly conserved, the nature of the behaviour does not dictate the neural mechanism and that the presence of homologous neural components does not determine the behaviour. This suggests that although behaviour is generated by neural circuits, natural selection can act separately on these two levels of biological organization.

  9. Attentional Loads Associated with Interlimb Interactions Underlying Rhythmic Bimanual Coordination

    ERIC Educational Resources Information Center

    Ridderikhoff, Arne; Peper, C. E.; Beek, Peter J.

    2008-01-01

    Studies of rhythmic bimanual coordination under dual-task conditions revealed (1) a dependence of secondary task performance on the stability of coordinative tasks, in that secondary task performance was better during in-phase than antiphase coordination, and (2) a shift in the mean relative phasing between the limbs compared to single-task…

  10. Rhythmic Priming Enhances the Phonological Processing of Speech

    ERIC Educational Resources Information Center

    Cason, Nia; Schon, Daniele

    2012-01-01

    While natural speech does not possess the same degree of temporal regularity found in music, there is recent evidence to suggest that temporal regularity enhances speech processing. The aim of this experiment was to examine whether speech processing would be enhanced by the prior presentation of a rhythmical prime. We recorded electrophysiological…

  11. Stereotactic body radiation therapy planning with duodenal sparing using volumetric-modulated arc therapy vs intensity-modulated radiation therapy in locally advanced pancreatic cancer: A dosimetric analysis

    SciTech Connect

    Kumar, Rachit; Wild, Aaron T.; Ziegler, Mark A.; Hooker, Ted K.; Dah, Samson D.; Tran, Phuoc T.; Kang, Jun; Smith, Koren; Zeng, Jing; Pawlik, Timothy M.; Tryggestad, Erik; Ford, Eric; Herman, Joseph M.

    2013-10-01

    Stereotactic body radiation therapy (SBRT) achieves excellent local control for locally advanced pancreatic cancer (LAPC), but may increase late duodenal toxicity. Volumetric-modulated arc therapy (VMAT) delivers intensity-modulated radiation therapy (IMRT) with a rotating gantry rather than multiple fixed beams. This study dosimetrically evaluates the feasibility of implementing duodenal constraints for SBRT using VMAT vs IMRT. Non–duodenal sparing (NS) and duodenal-sparing (DS) VMAT and IMRT plans delivering 25 Gy in 1 fraction were generated for 15 patients with LAPC. DS plans were constrained to duodenal D{sub max} of<30 Gy at any point. VMAT used 1 360° coplanar arc with 4° spacing between control points, whereas IMRT used 9 coplanar beams with fixed gantry positions at 40° angles. Dosimetric parameters for target volumes and organs at risk were compared for DS planning vs NS planning and VMAT vs IMRT using paired-sample Wilcoxon signed rank tests. Both DS VMAT and DS IMRT achieved significantly reduced duodenal D{sub mean}, D{sub max}, D{sub 1cc}, D{sub 4%}, and V{sub 20} {sub Gy} compared with NS plans (all p≤0.002). DS constraints compromised target coverage for IMRT as demonstrated by reduced V{sub 95%} (p = 0.01) and D{sub mean} (p = 0.02), but not for VMAT. DS constraints resulted in increased dose to right kidney, spinal cord, stomach, and liver for VMAT. Direct comparison of DS VMAT and DS IMRT revealed that VMAT was superior in sparing the left kidney (p<0.001) and the spinal cord (p<0.001), whereas IMRT was superior in sparing the stomach (p = 0.05) and the liver (p = 0.003). DS VMAT required 21% fewer monitor units (p<0.001) and delivered treatment 2.4 minutes faster (p<0.001) than DS IMRT. Implementing DS constraints during SBRT planning for LAPC can significantly reduce duodenal point or volumetric dose parameters for both VMAT and IMRT. The primary consequence of implementing DS constraints for VMAT is increased dose to other organs at

  12. Rhythmic Engagement with Music in Early Childhood: A Replication and Extension

    ERIC Educational Resources Information Center

    Ilari, Beatriz

    2015-01-01

    The purpose of this study was to replicate and extend previous findings on spontaneous movement and rhythmic engagement with music in infancy. Using the identical stimuli and procedures from the original study, I investigated spontaneous rhythmic movements in response to music, infant-directed speech, and contrasting rhythmic patterns in 30…

  13. Gait improvement via rhythmic stimulation in Parkinson’s disease is linked to rhythmic skills

    PubMed Central

    Bella, Simone Dalla; Benoit, Charles-Etienne; Farrugia, Nicolas; Keller, Peter E.; Obrig, Hellmuth; Mainka, Stefan; Kotz, Sonja A.

    2017-01-01

    Training based on rhythmic auditory stimulation (RAS) can improve gait in patients with idiopathic Parkinson’s disease (IPD). Patients typically walk faster and exhibit greater stride length after RAS. However, this effect is highly variable among patients, with some exhibiting little or no response to the intervention. These individual differences may depend on patients’ ability to synchronize their movements to a beat. To test this possibility, 14 IPD patients were submitted to RAS for four weeks, in which they walked to music with an embedded metronome. Before and after the training, patients’ synchronization was assessed with auditory paced hand tapping and walking to auditory cues. Patients increased gait speed and stride length in non-cued gait after training. However, individual differences were apparent as some patients showed a positive response to RAS and others, either no response, or a negative response. A positive response to RAS was predicted by the synchronization performance in hand tapping and gait tasks. More severe gait impairment, low synchronization variability, and a prompt response to a stimulation change foster a positive response to RAS training. Thus, sensorimotor timing skills underpinning the synchronization of steps to an auditory cue may allow predicting the success of RAS in IPD. PMID:28233776

  14. Gait improvement via rhythmic stimulation in Parkinson's disease is linked to rhythmic skills.

    PubMed

    Bella, Simone Dalla; Benoit, Charles-Etienne; Farrugia, Nicolas; Keller, Peter E; Obrig, Hellmuth; Mainka, Stefan; Kotz, Sonja A

    2017-02-24

    Training based on rhythmic auditory stimulation (RAS) can improve gait in patients with idiopathic Parkinson's disease (IPD). Patients typically walk faster and exhibit greater stride length after RAS. However, this effect is highly variable among patients, with some exhibiting little or no response to the intervention. These individual differences may depend on patients' ability to synchronize their movements to a beat. To test this possibility, 14 IPD patients were submitted to RAS for four weeks, in which they walked to music with an embedded metronome. Before and after the training, patients' synchronization was assessed with auditory paced hand tapping and walking to auditory cues. Patients increased gait speed and stride length in non-cued gait after training. However, individual differences were apparent as some patients showed a positive response to RAS and others, either no response, or a negative response. A positive response to RAS was predicted by the synchronization performance in hand tapping and gait tasks. More severe gait impairment, low synchronization variability, and a prompt response to a stimulation change foster a positive response to RAS training. Thus, sensorimotor timing skills underpinning the synchronization of steps to an auditory cue may allow predicting the success of RAS in IPD.

  15. Blood pressure rhythmicity and visceral fat in children with hypertension.

    PubMed

    Niemirska, Anna; Litwin, Mieczysław; Feber, Janusz; Jurkiewicz, Elżbieta

    2013-10-01

    Primary hypertension is associated with disturbed activity of the sympathetic nervous system and altered blood pressure rhythmicity. We analyzed changes in cardiovascular rhythmicity and its relation with target organ damage during 12 months of antihypertensive treatment in 50 boys with hypertension (median, 15.0 years). The following parameters were obtained before and after 12 months of antihypertensive treatment: 24-hour ambulatory blood pressure, left ventricular mass, carotid intima-media thickness, and MRI for visceral and subcutaneous adipose tissue. Amplitudes and acrophases of mean arterial pressure and heart rate rhythms were obtained for 24-, 12-, and 8-hour periods. After 1 year of treatment, 68% of patients were normotensive, and left ventricular mass and carotid intima-media thickness decreased in 60% and 62% of patients, respectively. Blood pressure and heart rate rhythmicity patterns did not change. Changes in blood pressure amplitude correlated with the decrease of waist circumference (P=0.035). Moreover, the decrease of visceral fat correlated with the decrease of 24-hour mean arterial pressure and heart rate acrophases (both P<0.05). There were no differences in changes of blood pressure and heart rate rhythms between patients who achieved or did not achieve normotension and regression of left ventricular mass and carotid intima-media thickness. It was concluded that abnormal cardiovascular rhythmicity persists in children with primary hypertension despite effective antihypertensive treatment, which suggests that it may be the primary abnormality. The correlation between changes in cardiovascular rhythmicity and visceral obesity may indicate that the visceral fat plays an important role in the sympathetic activity of adolescents with hypertension.

  16. Neural Microstates Govern Perception of Auditory Input without Rhythmic Structure.

    PubMed

    Henry, Molly J; Herrmann, Björn; Obleser, Jonas

    2016-01-20

    Human perception fluctuates with the phase of neural oscillations in the presence of environmental rhythmic structure by which neural oscillations become entrained. However, in the absence of predictability afforded by rhythmic structure, we hypothesize that the neural dynamical states associated with optimal psychophysical performance are more complex than what has been described previously for rhythmic stimuli. The current electroencephalography study characterized the brain dynamics associated with optimal detection of gaps embedded in narrow-band acoustic noise stimuli lacking low-frequency rhythmic structure. Optimal gap detection was associated with three spectrotemporally distinct delta-governed neural microstates. Individual microstates were characterized by unique instantaneous combinations of neural phase in the delta, theta, and alpha frequency bands. Critically, gap detection was not predictable from local fluctuations in stimulus acoustics. The current results suggest that, in the absence of rhythmic structure to entrain neural oscillations, good performance hinges on complex neural states that vary from moment to moment. Significance statement: Our ability to hear faint sounds fluctuates together with slow brain activity that synchronizes with environmental rhythms. However, it is so far not known how brain activity at different time scales might interact to influence perception when there is no rhythm with which brain activity can synchronize. Here, we used electroencephalography to measure brain activity while participants listened for short silences that interrupted ongoing noise. We examined brain activity in three different frequency bands: delta, theta, and alpha. Participants' ability to detect gaps depended on different numbers of frequency bands--sometimes one, sometimes two, and sometimes three--at different times. Changes in the number of frequency bands that predict perception are a hallmark of a complex neural system.

  17. Transitions between discrete and rhythmic primitives in a unimanual task

    PubMed Central

    Sternad, Dagmar; Marino, Hamal; Charles, Steven K.; Duarte, Marcos; Dipietro, Laura; Hogan, Neville

    2013-01-01

    Given the vast complexity of human actions and interactions with objects, we proposed that control of sensorimotor behavior may utilize dynamic primitives. However, greater computational simplicity may come at the cost of reduced versatility. Evidence for primitives may be garnered by revealing such limitations. This study tested subjects performing a sequence of progressively faster discrete movements in order to “stress” the system. We hypothesized that the increasing pace would elicit a transition to rhythmic movements, assumed to be computationally and neurally more efficient. Abrupt transitions between the two types of movements would support the hypothesis that rhythmic and discrete movements are distinct primitives. Ten subjects performed planar point-to-point arm movements paced by a metronome: starting at 2 s, the metronome intervals decreased by 36 ms per cycle to 200 ms, stayed at 200 ms for several cycles, then increased by similar increments. Instructions emphasized to insert explicit stops between each movement with a duration that equaled the movement time. The experiment was performed with eyes open and closed, and with short and long metronome sounds, the latter explicitly specifying the dwell duration. Results showed that subjects matched instructed movement times but did not preserve the dwell times. Rather, they progressively reduced dwell time to zero, transitioning to continuous rhythmic movements before movement times reached their minimum. The acceleration profiles showed an abrupt change between discrete and rhythmic profiles. The loss of dwell time occurred earlier with long auditory specification, when subjects also showed evidence of predictive control. While evidence for hysteresis was weak, taken together, the results clearly indicated a transition between discrete and rhythmic movements, supporting the proposal that representation is based on primitives rather than on veridical internal models. PMID:23888139

  18. Assessment of rhythmic entrainment at multiple timescales in dyslexia: Evidence for disruption to syllable timing☆

    PubMed Central

    Leong, Victoria; Goswami, Usha

    2014-01-01

    Developmental dyslexia is associated with rhythmic difficulties, including impaired perception of beat patterns in music and prosodic stress patterns in speech. Spoken prosodic rhythm is cued by slow (<10 Hz) fluctuations in speech signal amplitude. Impaired neural oscillatory tracking of these slow amplitude modulation (AM) patterns is one plausible source of impaired rhythm tracking in dyslexia. Here, we characterise the temporal profile of the dyslexic rhythm deficit by examining rhythmic entrainment at multiple speech timescales. Adult dyslexic participants completed two experiments aimed at testing the perception and production of speech rhythm. In the perception task, participants tapped along to the beat of 4 metrically-regular nursery rhyme sentences. In the production task, participants produced the same 4 sentences in time to a metronome beat. Rhythmic entrainment was assessed using both traditional rhythmic indices and a novel AM-based measure, which utilised 3 dominant AM timescales in the speech signal each associated with a different phonological grain-sized unit (0.9–2.5 Hz, prosodic stress; 2.5–12 Hz, syllables; 12–40 Hz, phonemes). The AM-based measure revealed atypical rhythmic entrainment by dyslexic participants to syllable patterns in speech, in perception and production. In the perception task, both groups showed equally strong phase-locking to Syllable AM patterns, but dyslexic responses were entrained to a significantly earlier oscillatory phase angle than controls. In the production task, dyslexic utterances showed shorter syllable intervals, and differences in Syllable:Phoneme AM cross-frequency synchronisation. Our data support the view that rhythmic entrainment at slow (∼5 Hz, Syllable) rates is atypical in dyslexia, suggesting that neural mechanisms for syllable perception and production may also be atypical. These syllable timing deficits could contribute to the atypical development of phonological representations for

  19. Absence of arterial baroreflex modulation of skin sympathetic activity and sweat rate during whole-body heating in humans

    NASA Technical Reports Server (NTRS)

    Wilson, T. E.; Cui, J.; Crandall, C. G.

    2001-01-01

    1. Prior findings suggest that baroreflexes are capable of modulating skin blood flow, but the effects of baroreceptor loading/unloading on sweating are less clear. Therefore, this project tested the hypothesis that pharmacologically induced alterations in arterial blood pressure in heated humans would lead to baroreflex-mediated changes in both skin sympathetic nerve activity (SSNA) and sweat rate. 2. In seven subjects mean arterial blood pressure was lowered (approximately 8 mmHg) and then raised (approximately 13 mmHg) by bolus injections of sodium nitroprusside and phenylephrine, respectively. Moreover, in a separate protocol, arterial blood pressure was reduced via steady-state administration of sodium nitroprusside. In both normothermia and heat-stress conditions the following responses were monitored: sublingual and mean skin temperatures, heart rate, beat-by-beat blood pressure, skin blood flow (laser-Doppler flowmetry), local sweat rate and SSNA (microneurography from peroneal nerve). 3. Whole-body heating increased skin and sublingual temperatures, heart rate, cutaneous blood flow, sweat rate and SSNA, but did not change arterial blood pressure. Heart rate was significantly elevated (from 74 +/- 3 to 92 +/- 4 beats x min(-1); P < 0.001) during bolus sodium nitroprusside-induced reductions in blood pressure, and significantly reduced (from 92 +/- 4 to 68 +/- 4 beats x min(-1); P < 0.001) during bolus phenylephrine-induced elevations in blood pressure, thereby demonstrating normal baroreflex function in these subjects. 4. Neither SSNA nor sweat rate was altered by rapid (bolus infusion) or sustained (steady-state infusion) changes in blood pressure regardless of the thermal condition. 5. These data suggest that SSNA and sweat rate are not modulated by arterial baroreflexes in normothermic or moderately heated individuals.

  20. Improving Delivery Accuracy of Stereotactic Body Radiotherapy to a Moving Tumor Using Simplified Volumetric Modulated Arc Therapy

    PubMed Central

    Ko, Young Eun; Cho, Byungchul; Kim, Su Ssan; Song, Si Yeol; Choi, Eun Kyung; Ahn, Seung Do; Yi, Byongyong

    2016-01-01

    Purpose To develop a simplified volumetric modulated arc therapy (VMAT) technique for more accurate dose delivery in thoracic stereotactic body radiation therapy (SBRT). Methods and Materials For each of the 22 lung SBRT cases treated with respiratory-gated VMAT, a dose rate modulated arc therapy (DrMAT) plan was retrospectively generated. A dynamic conformal arc therapy plan with 33 adjoining coplanar arcs was designed and their beam weights were optimized by an inverse planning process. All sub-arc beams were converted into a series of control points with varying MLC segment and dose rates and merged into an arc beam for a DrMAT plan. The plan quality of original VMAT and DrMAT was compared in terms of target coverage, compactness of dose distribution, and dose sparing of organs at risk. To assess the delivery accuracy, the VMAT and DrMAT plans were delivered to a motion phantom programmed with the corresponding patients’ respiratory signal; results were compared using film dosimetry with gamma analysis. Results The plan quality of DrMAT was equivalent to that of VMAT in terms of target coverage, dose compactness, and dose sparing for the normal lung. In dose sparing for other critical organs, DrMAT was less effective than VMAT for the spinal cord, heart, and esophagus while being well within the limits specified by the Radiation Therapy Oncology Group. Delivery accuracy of DrMAT to a moving target was similar to that of VMAT using a gamma criterion of 2%/2mm but was significantly better using a 2%/1mm criterion, implying the superiority of DrMAT over VMAT in SBRT for thoracic/abdominal tumors with respiratory movement. Conclusion We developed a DrMAT technique for SBRT that produces plans of a quality similar to that achieved with VMAT but with better delivery accuracy. This technique is well-suited for small tumors with motion uncertainty. PMID:27333199

  1. Octopamine and Dopamine differentially modulate the nicotine-induced calcium response in Drosophila Mushroom Body Kenyon Cells.

    PubMed

    Leyton, V; Goles, N I; Fuenzalida-Uribe, N; Campusano, J M

    2014-02-07

    In Drosophila associative olfactory learning, an odor, the conditioned stimulus (CS), is paired to an unconditioned stimulus (US). The CS and US information arrive at the Mushroom Bodies (MB), a Drosophila brain region that processes the information to generate new memories. It has been shown that olfactory information is conveyed through cholinergic inputs that activate nicotinic acetylcholine receptors (nAChRs) in the MB, while the US is coded by biogenic amine (BA) systems that innervate the MB. In this regard, the MB acts as a coincidence detector. A better understanding of the properties of the responses gated by nicotinic and BA receptors is required to get insights on the cellular and molecular mechanisms responsible for memory formation. In recent years, information has become available on the properties of the responses induced by nAChR activation in Kenyon Cells (KCs), the main neuronal MB population. However, very little information exists on the responses induced by aminergic systems in fly MB. Here we have evaluated some of the properties of the calcium responses gated by Dopamine (DA) and Octopamine (Oct) in identified KCs in culture. We report that exposure to BAs induces a fast but rather modest increase in intracellular calcium levels in cultured KCs. The responses to Oct and DA are fully blocked by a VGCC blocker, while they are differentially modulated by cAMP. Moreover, co-application of BAs and nicotine has different effects on intracellular calcium levels: while DA and nicotine effects are additive, Oct and nicotine induce a synergistic increase in calcium levels. These results suggest that a differential modulation of nicotine-induced calcium increase by DA and Oct could contribute to the events leading to learning and memory in flies.

  2. Perturbed rhythmic activation of signaling pathways in mice deficient for Sterol Carrier Protein 2-dependent diurnal lipid transport and metabolism.

    PubMed

    Jouffe, Céline; Gobet, Cédric; Martin, Eva; Métairon, Sylviane; Morin-Rivron, Delphine; Masoodi, Mojgan; Gachon, Frédéric

    2016-04-21

    Through evolution, most of the living species have acquired a time keeping system to anticipate daily changes caused by the rotation of the Earth. In all of the systems this pacemaker is based on a molecular transcriptional/translational negative feedback loop able to generate rhythmic gene expression with a period close to 24 hours. Recent evidences suggest that post-transcriptional regulations activated mostly by systemic cues play a fundamental role in the process, fine tuning the time keeping system and linking it to animal physiology. Among these signals, we consider the role of lipid transport and metabolism regulated by SCP2. Mice harboring a deletion of the Scp2 locus present a modulated diurnal accumulation of lipids in the liver and a perturbed activation of several signaling pathways including PPARα, SREBP, LRH-1, TORC1 and its upstream regulators. This defect in signaling pathways activation feedbacks upon the clock by lengthening the circadian period of animals through post-translational regulation of core clock regulators, showing that rhythmic lipid transport is a major player in the establishment of rhythmic mRNA and protein expression landscape.

  3. Perturbed rhythmic activation of signaling pathways in mice deficient for Sterol Carrier Protein 2-dependent diurnal lipid transport and metabolism

    PubMed Central

    Jouffe, Céline; Gobet, Cédric; Martin, Eva; Métairon, Sylviane; Morin-Rivron, Delphine; Masoodi, Mojgan; Gachon, Frédéric

    2016-01-01

    Through evolution, most of the living species have acquired a time keeping system to anticipate daily changes caused by the rotation of the Earth. In all of the systems this pacemaker is based on a molecular transcriptional/translational negative feedback loop able to generate rhythmic gene expression with a period close to 24 hours. Recent evidences suggest that post-transcriptional regulations activated mostly by systemic cues play a fundamental role in the process, fine tuning the time keeping system and linking it to animal physiology. Among these signals, we consider the role of lipid transport and metabolism regulated by SCP2. Mice harboring a deletion of the Scp2 locus present a modulated diurnal accumulation of lipids in the liver and a perturbed activation of several signaling pathways including PPARα, SREBP, LRH-1, TORC1 and its upstream regulators. This defect in signaling pathways activation feedbacks upon the clock by lengthening the circadian period of animals through post-translational regulation of core clock regulators, showing that rhythmic lipid transport is a major player in the establishment of rhythmic mRNA and protein expression landscape. PMID:27097688

  4. Rhythmic Trafficking of TRPV2 in the Suprachiasmatic Nucleus is Regulated by Prokineticin 2 Signaling

    PubMed Central

    Burton, Katherine J.; Li, Xiaohan; Li, Jia-Da; Hu, Wang-Ping

    2015-01-01

    The mammalian circadian clock is composed of single-cell oscillators. Neurochemical and electrical signaling among these oscillators is important for the normal expression of circadian rhythms. Prokineticin 2 (PK2), encoding a cysteine-rich secreted protein, has been shown to be a critical signaling molecule for the regulation of circadian rhythms. PK2 expression in the suprachiasmatic nucleus (SCN) is highly rhythmic, peaking during the day and being essentially absent during the night. Mice with disrupted PK2 gene or its receptor PKR2 display greatly reduced rhythmicity of broad circadian parameters such as locomotor activity, body temperature and sleep/wake patterns. PK2 has been shown to increase the firing rate of SCN neurons, with unknown molecular mechanisms. Here we report that TRPV2, an ion channel belonging to the family of TRP, is co-expressed with PKR2 in the SCN neurons. Further, TRPV2 protein, but not TRPV2 mRNA, was shown to oscillate in the SCN in a PK2-dependent manner. Functional studies revealed that TRPV2 enhanced signaling of PKR2 in calcium mobilization or ion current conductance, likely via the increased trafficking of TRPV2 to the cell surface. Taken together, these results indicate that TRPV2 is likely part of the downstream signaling of PK2 in the regulation of the circadian rhythms. PMID:27103928

  5. Role for kisspeptin/neurokinin B/dynorphin (KNDy) neurons in cutaneous vasodilatation and the estrogen modulation of body temperature

    PubMed Central

    Mittelman-Smith, Melinda A.; Williams, Hemalini; Krajewski-Hall, Sally J.; McMullen, Nathaniel T.; Rance, Naomi E.

    2012-01-01

    Estrogen withdrawal in menopausal women leads to hot flushes, a syndrome characterized by the episodic activation of heat dissipation effectors. Despite the extraordinary number of individuals affected, the etiology of flushes remains an enigma. Because menopause is accompanied by marked alterations in hypothalamic kisspeptin/neurokinin B/dynorphin (KNDy) neurons, we hypothesized that these neurons could contribute to the generation of flushes. To determine if KNDy neurons participate in the regulation of body temperature, we evaluated the thermoregulatory effects of ablating KNDy neurons by injecting a selective toxin for neurokinin-3 expressing neurons [NK3-saporin (SAP)] into the rat arcuate nucleus. Remarkably, KNDy neuron ablation consistently reduced tail-skin temperature (TSKIN), indicating that KNDy neurons facilitate cutaneous vasodilatation, an important heat dissipation effector. Moreover, KNDy ablation blocked the reduction of TSKIN by 17β-estradiol (E2), which occurred in the environmental chamber during the light phase, but did not affect the E2 suppression of TSKIN during the dark phase. At the high ambient temperature of 33 °C, the average core temperature (TCORE) of ovariectomized (OVX) control rats was significantly elevated, and this value was reduced by E2 replacement. In contrast, the average TCORE of OVX, KNDy-ablated rats was lower than OVX control rats at 33 °C, and not altered by E2 replacement. These data provide unique evidence that KNDy neurons promote cutaneous vasodilatation and participate in the E2 modulation of body temperature. Because cutaneous vasodilatation is a cardinal sign of a hot flush, these results support the hypothesis that KNDy neurons could play a role in the generation of flushes. PMID:23150555

  6. Mango modulates body fat and plasma glucose and lipids in mice fed a high-fat diet.

    PubMed

    Lucas, Edralin A; Li, Wenjia; Peterson, Sandra K; Brown, Angela; Kuvibidila, Solo; Perkins-Veazie, Penny; Clarke, Stephen L; Smith, Brenda J

    2011-11-01

    Consumption of fruits and vegetables has been investigated for their role in the prevention of many chronic conditions. Among the fruits, mango provides numerous bioactive compounds such as carotenoids, vitamin C and phenolic compounds, which have been shown to have antioxidant and anti-inflammatory properties. The present study examined the effects of dietary supplementation of freeze-dried mango pulp, in comparison with the hypolipidaemic drug, fenofibrate, and the hypoglycaemic drug, rosiglitazone, in reducing adiposity and alterations in glucose metabolism and lipid profile in mice fed a high-fat (HF) diet. Male C57BL/6J mice were randomly divided into six treatment groups (eight to nine/group): control (10 % energy from fat); HF (60 % energy from fat); HF+1 or 10 % freeze-dried mango (w/w); HF+fenofibrate (500 mg/kg diet); HF+rosiglitazone (50 mg/kg diet). After 8 weeks of treatment, mice receiving the HF diet had a higher percentage body fat (P = 0·0205) and epididymal fat mass (P = 0·0037) compared with the other treatment groups. Both doses of freeze-dried mango, similar to fenofibrate and rosiglitazone, prevented the increase in epididymal fat mass and the percentage of body fat. Freeze-dried mango supplementation at the 1 % dose improved glucose tolerance as shown by approximately 35 % lower blood glucose area under the curve compared with the HF group. Moreover, freeze-dried mango lowered insulin resistance, as indicated by the homeostasis model assessment of insulin resistance, to a similar extent as rosiglitazone and modulated NEFA. The present findings demonstrate that incorporation of freeze-dried mango in the diet of mice improved glucose tolerance and lipid profile and reduced adiposity associated with a HF diet.

  7. Role for kisspeptin/neurokinin B/dynorphin (KNDy) neurons in cutaneous vasodilatation and the estrogen modulation of body temperature.

    PubMed

    Mittelman-Smith, Melinda A; Williams, Hemalini; Krajewski-Hall, Sally J; McMullen, Nathaniel T; Rance, Naomi E

    2012-11-27

    Estrogen withdrawal in menopausal women leads to hot flushes, a syndrome characterized by the episodic activation of heat dissipation effectors. Despite the extraordinary number of individuals affected, the etiology of flushes remains an enigma. Because menopause is accompanied by marked alterations in hypothalamic kisspeptin/neurokinin B/dynorphin (KNDy) neurons, we hypothesized that these neurons could contribute to the generation of flushes. To determine if KNDy neurons participate in the regulation of body temperature, we evaluated the thermoregulatory effects of ablating KNDy neurons by injecting a selective toxin for neurokinin-3 expressing neurons [NK(3)-saporin (SAP)] into the rat arcuate nucleus. Remarkably, KNDy neuron ablation consistently reduced tail-skin temperature (T(SKIN)), indicating that KNDy neurons facilitate cutaneous vasodilatation, an important heat dissipation effector. Moreover, KNDy ablation blocked the reduction of T(SKIN) by 17β-estradiol (E(2)), which occurred in the environmental chamber during the light phase, but did not affect the E(2) suppression of T(SKIN) during the dark phase. At the high ambient temperature of 33 °C, the average core temperature (T(CORE)) of ovariectomized (OVX) control rats was significantly elevated, and this value was reduced by E(2) replacement. In contrast, the average T(CORE) of OVX, KNDy-ablated rats was lower than OVX control rats at 33 °C, and not altered by E(2) replacement. These data provide unique evidence that KNDy neurons promote cutaneous vasodilatation and participate in the E(2) modulation of body temperature. Because cutaneous vasodilatation is a cardinal sign of a hot flush, these results support the hypothesis that KNDy neurons could play a role in the generation of flushes.

  8. Motor activity and imagery modulate the body-selective region in the occipital-temporal area: a near-infrared spectroscopy study.

    PubMed

    Ishizu, Tomohiro; Noguchi, Asuka; Ito, Yoshie; Ayabe, Tomoaki; Kojima, Shozo

    2009-11-06

    The extrastriate body area (EBA) lies in the occipital-temporal cortex and has been described as a "body-selective" region that responds when viewing other people's bodies. Recently, several studies have reported that EBA is also modulated when the subject moves or imagines moving their own body, even without visual feedback. The present study involved 3 experiments, wherein the first experiment was conducted to examine whether near-infrared spectroscopy (NIRS) could capture any activity in the EBA when viewing images of bodies. The second experiment was designed to elucidate whether this region also responds when the subjects move their own body, and the third to observe whether imagining carrying out a movement would activate EBA. Images of human bodies and chairs were used as the stimuli for the first experiment, simple hand movements carried out by the subject were used for the second and the act of imagining hand movements for the third. Our results confirmed that the region we defined as EBA was clearly activated when the subject viewed images of human bodies, carried out movements of their own body and imagined moving parts of their own body, thus demonstrating the usefulness of NIRS as a new brain imaging method. Moreover, we found a gender-based difference when imagining movement; male subjects showed a greater response than female subjects. This may reflect a gender difference in imagery skills; however, further research is needed to verify this hypothesis.

  9. Evidence for daily and weekly rhythmicity but not lunar or seasonal rhythmicity of physical activity in a large cohort of individuals from five different countries

    PubMed Central

    Refinetti, Roberto; Sani, Mamane; Jean-Louis, Girardin; Pandi-Perumal, Seithikurippu R.; Durazo-Arvizu, Ramon A.; Dugas, Lara R.; Kafensztok, Ruth; Bovet, Pascal; Forrester, Terrence E.; Lambert, Estelle V.; Plange-Rhule, Jacob; Luke, Amy

    2015-01-01

    Background Biological rhythmicity has been extensively studied in animals for many decades. Although temporal patterns of physical activity have been identified in humans, no large scale, multi-national study has been published, and no comparison has been attempted of the ubiquity of activity rhythms at different time scales (such as daily, weekly, monthly, and annual). Methods Using individually-worn actigraphy devices, physical activity of 2,328 individuals from five different countries (adults of African descent from Ghana, South Africa, Jamaica, Seychelles, and the United States) was measured for seven consecutive days at different times of the year. Results Analysis for rhythmic patterns identified daily rhythmicity of physical activity in all five of the represented nationalities. Weekly rhythmicity was found in some, but not all, of the nationalities. No significant evidence of lunar rhythmicity or seasonal rhythmicity was found in any of the groups. Conclusions These findings extend previous small-scale observations of daily rhythmicity to a large cohort of individuals from around the world. The findings also confirm the existence of modest weekly rhythmicity but not lunar or seasonal rhythmicity in human activity. These differences in rhythm strength have implications for the management of health hazards of rhythm misalignment. PMID:26402449

  10. Effects of Electroacupuncture on the Daily Rhythmicity of Intestinal Movement and Circadian Rhythmicity of Colonic Per2 Expression in Rats with Spinal Cord Injury

    PubMed Central

    Wang, Xueqiang; Zhang, Wenyi; Xie, Bin; Zhu, Zhaojin; Lu, Yuemei

    2016-01-01

    Background. Spinal cord injury (SCI) leads to bowel dysfunction. Electroacupuncture (EA) may improve bowel function. Objective. To assess EA on daily rhythmicity of intestinal movement and circadian rhythmicity of colonic Per2 expression in rats with SCI. Methods. Rats were randomized to the sham, SCI, and SCI+EA groups. EA was performed at bilateral Zusanli point (ST36) during daytime (11:00–11:30) for 14 days following SCI. Intestinal transit and daily rhythmicity of intestinal movement were assessed. Circadian rhythmicity of colonic Per2 expression was assessed by real-time RT-PCR. Results. EA shortened the stool efflux time and increased the dry fecal weight within 24 h in SCI rats. Daily rhythmicity of intestinal movements was unaffected by SCI. The expression of colonic Per2 peaked at 20:00 and the nadir was observed at 8:00 in the SCI and sham groups. In the SCI+EA group, colonic Per2 expression peaked at 12:00 and 20:00, and the nadir was observed at 8:00. Conclusion. SCI did not change the circadian rhythmicity of colonic Per2 expression in rats, and daily intestinal movement rhythmicity was retained. EA changed the daily rhythmicity of intestinal movement and the circadian rhythmicity of colonic Per2 expression in rats with SCI, increasing Per2 expression shortly after EA treatment. PMID:27999821

  11. Use of chi square periodogram in the analysis of estrous rhythmicity.

    PubMed

    Refinetti, R

    1991-02-01

    The usefulness of the chi square periodogram procedure for the analysis of estrous rhythmicity was investigated. Sokolove-Bushell's Q statistic was found to have a chi square distribution at the small degrees of freedom involved in estrous rhythmicity in rodents (i.e., rhythmicity with periods of 2-7 days). Consequently, the significance of the peaks in the periodogram can be effectively evaluated. The effects of multiple-period rhythmicity and of random noise added to periodical data were also investigated. Overall, the analysis of simulated as well as empirical data indicated that the chi square periodogram is an excellent tool for the evaluation of estrous rhythmicity.

  12. Energy intake and the circadian rhythm of core body temperature in sheep

    PubMed Central

    Maloney, Shane K; Meyer, Leith C R; Blache, D; Fuller, A

    2013-01-01

    We tested the hypothesis that different levels of energy intake would alter the circadian rhythm of core body temperature (Tc) in ovariectomized sheep. We measured arterial blood temperature every 5 min while ten sheep were offered a maintenance diet, 70% of maintenance requirements, or 150% of maintenance requirements, for 12 days, and later fasted for 2 days. The rhythmicity of Tc was analyzed for its dominant period and then a least-squares cosine wave was fitted to the data that generated a mesor, amplitude, and acrophase for the rhythm. When energy intake was less than maintenance requirements we observed a significant decrease in the mesor and minimum, and a significant increase in the amplitude and goodness of fit, of the body temperature rhythm. Fasting also resulted in a decrease in the maximum of the body temperature rhythm. Feeding the sheep to excess did not affect the mesor or maximum of the rhythm, but did result in a decrease in the goodness of fit of the rhythm in those sheep that consumed more energy than when they were on the maintenance diet, indicating that circadian rhythmicity was decreased when energy intake increased. Our data indicate that modulation of the circadian rhythm of body temperature, characterized by inactive-phase hypothermia, occurs when energy intake is reduced. The response may be an adaptation to energy imbalance in large mammals. PMID:24303185

  13. MicroRNA mir-16 is anti-proliferative in enterocytes and exhibits diurnal rhythmicity in intestinal crypts

    SciTech Connect

    Balakrishnan, Anita; Stearns, Adam T.; Park, Peter J.; Dreyfuss, Jonathan M.; Ashley, Stanley W.; Rhoads, David B.; Tavakkolizadeh, Ali

    2010-12-10

    Background and aims: The intestine exhibits profound diurnal rhythms in function and morphology, in part due to changes in enterocyte proliferation. The regulatory mechanisms behind these rhythms remain largely unknown. We hypothesized that microRNAs are involved in mediating these rhythms, and studied the role of microRNAs specifically in modulating intestinal proliferation. Methods: Diurnal rhythmicity of microRNAs in rat jejunum was analyzed by microarrays and validated by qPCR. Temporal expression of diurnally rhythmic mir-16 was further quantified in intestinal crypts, villi, and smooth muscle using laser capture microdissection and qPCR. Morphological changes in rat jejunum were assessed by histology and proliferation by immunostaining for bromodeoxyuridine. In IEC-6 cells stably overexpressing mir-16, proliferation was assessed by cell counting and MTS assay, cell cycle progression and apoptosis by flow cytometry, and cell cycle gene expression by qPCR and immunoblotting. Results: mir-16 peaked 6 hours after light onset (HALO 6) with diurnal changes restricted to crypts. Crypt depth and villus height peaked at HALO 13-14 in antiphase to mir-16. Overexpression of mir-16 in IEC-6 cells suppressed specific G1/S regulators (cyclins D1-3, cyclin E1 and cyclin-dependent kinase 6) and produced G1 arrest. Protein expression of these genes exhibited diurnal rhythmicity in rat jejunum, peaking between HALO 11 and 17 in antiphase to mir-16. Conclusions: This is the first report of circadian rhythmicity of specific microRNAs in rat jejunum. Our data provide a link between anti-proliferative mir-16 and the intestinal proliferation rhythm and point to mir-16 as an important regulator of proliferation in jejunal crypts. This function may be essential to match proliferation and absorptive capacity with nutrient availability.

  14. Investigation of the effects of transcranial alternating current stimulation (tACS) on self-paced rhythmic movements.

    PubMed

    Varlet, Manuel; Wade, Alanna; Novembre, Giacomo; Keller, Peter E

    2017-03-18

    Human rhythmic movements spontaneously entrain to external rhythmic stimuli. Such sensory-motor entrainment can attract movements to different tempi and enhance their efficiency, with potential clinical applications for motor rehabilitation. Here we investigate whether entrainment of self-paced rhythmic movements can be induced via transcranial alternating current stimulation (tACS), which uses alternating currents to entrain spontaneous brain oscillations at specific frequencies. Participants swung a handheld pendulum at their preferred tempo with the right hand while tACS was applied over their left or right primary motor cortex at frequencies equal to their preferred tempo (Experiment 1) or in the alpha (10Hz) and beta (20Hz) ranges (Experiment 2). Given that entrainment generally occurs only if the frequency difference between two rhythms is small, stimulations were delivered at frequencies equal to participants' preferred movement tempo (≈1Hz) and ±12.5% in Experiment 1, and at 10Hz and 20Hz, and ±12.5% in Experiment 2. The comparison of participants' movement frequency, amplitude, variability, and phase synchrony with and without tACS failed to reveal entrainment or movement modifications across the two experiments. However, significant differences in stimulation-related side effects reported by participants were found between the two experiments, with phosphenes and burning sensations principally occurring in Experiment 2, and metallic tastes reported marginally more often in Experiment 1. Although other stimulation protocols may be effective, our results suggest that rhythmic movements such as pendulum swinging or locomotion that are low in goal-directedness and/or strongly driven by peripheral and mechanical constraints may not be susceptible to modulation by tACS.

  15. Body Sodium Overload Modulates the Firing Rate and Fos Immunoreactivity of Serotonergic Cells of Dorsal Raphe Nucleus

    PubMed Central

    Godino, Andrea; Pitra, Soledad; Carrer, Hugo F.; Vivas, Laura

    2013-01-01

    In order to determine whether serotonergic (5HT) dorsal raphe nucleus (DRN) cells are involved in body sodium status regulation, the effect of a s.c. infusion of either 2 M or 0.15 M NaCl on 5HT DRN neuron firing was studied using single unit extracellular recordings. In separate groups of 2 M and 0.15 M NaCl-infused rats, water intake, oxytocin (OT) plasma concentration, urine and plasma sodium and protein concentrations were also measured. Also, to determine the involvement of particular brain nuclei and neurochemical systems in body sodium overload (SO), animals from both groups were perfused for brain immunohistochemical detection of Fos, Fos-OT and Fos-5HT expression. SO produced a significant increase in serotonergic DRN neuron firing rate compared to baseline and 0.15 M NaCl-infused rats. As expected, 2 M NaCl s.c. infusion also induced a significant increase of water intake, diuresis and natriuresis, plasma sodium concentration and osmolality, even though plasma volume did not increase as indicated by changes in plasma protein concentration. The distribution of neurons along the forebrain and brainstem expressing Fos after SO showed the participation of the lamina terminalis, extended amygdala, supraoptic and paraventricular hypothalamic nuclei in the neural network that controls osmoregulatory responses. Both Fos-OT immunoreactive and plasma OT concentration increased after s.c. hypertonic sodium infusion. Finally, matching the “in vivo” electrophysiological study, SO doubled the number of Fos-5HT immunolabeled cells within the DRN. In summary, the results characterize the behavioral, renal and endocrine responses after body sodium overload without volume expansion and specify the cerebral nuclei that participate at different CNS levels in the control of these responses. The electrophysiological approach also allows us to determine in an “in vivo" model that DRN 5HT neurons increase their firing frequency during an increase in systemic sodium

  16. Phase I dose-escalation study of helical intensity-modulated radiotherapy-based stereotactic body radiotherapy for hepatocellular carcinoma

    PubMed Central

    Kim, Jun Won; Seong, Jinsil; Lee, Ik Jae; Woo, Joong Yeol; Han, Kwang-Hyub

    2016-01-01

    Background Phase I trial was conducted to determine feasibility and toxicity of helical intensity-modulated radiotherapy (IMRT)-based stereotactic body radiotherapy (SBRT) for hepatocellular carcinoma (HCC). Results Eighteen patients (22 lesions) were enrolled. With no DLT at 52 Gy (13 Gy/fraction), protocol was amended for further escalation to 60 Gy (15 Gy/fraction). Radiologic complete response rate was 88.9%. Two outfield intrahepatic, 2 distant, 4 concurrent local and outfield, and 1 concurrent local, outfield and distant failures (no local failure at dose levels 3–4) occurred. The worst toxicity was grade 3 hematologic in five patients, with no gastrointestinal toxicity > grade 1. At median follow-up of 28 months for living patients, 2-year local control, progression-free (PFS), and overall survival rates were 71.3%, 49.4% and 69.3%, respectively. Multi-segmental recurrences prior to SBRT was independent prognostic factor for PFS (p = 0.033). Materials and Methods Eligible patients had Child-Pugh's class A or B, unresectable HCC, ≤ 3 lesions, and cumulative tumor diameter ≤ 6 cm. Starting at 36 Gy in four fractions, dose was escalated with 2 Gy/fraction per dose-level. CTCAE v 3.0 ≥ grade 3 gastrointestinal toxicity and radiation induced liver disease defined dose-limiting toxicity (DLT). Conclusions Helical IMRT-based SBRT was tolerable and showed encouraging results. Confirmatory phase II trial is underway. PMID:27213593

  17. Altering cAMP levels within a central pattern generator modifies or disrupts rhythmic motor output.

    PubMed

    Clemens, Stefan; Calin-Jageman, Robert; Sakurai, Akira; Katz, Paul S

    2007-12-01

    Cyclic AMP is a second messenger that has been implicated in the neuromodulation of rhythmically active motor patterns. Here, we tested whether manipulating cAMP affects swim motor pattern generation in the mollusc, Tritonia diomedea. Inhibiting adenylyl cyclase (AC) with 9-cyclopentyladenine (9-CPA) slowed or stopped the swim motor pattern. Inhibiting phosphodiesterase with 3-isobutyl-1-methylxanthine (IBMX) or applying dibutyryl-cAMP (dB-cAMP) disrupted the swim motor pattern, as did iontophoresing cAMP into the central pattern generator neuron C2. Additionally, during wash-in, IBMX sometimes temporarily produced extended or spontaneous swim motor patterns. Photolysis of caged cAMP in C2 after initiation of the swim motor pattern inhibited subsequent bursting. These results suggest that cAMP levels can dynamically modulate swim motor pattern generation, possibly shaping the output of the central pattern generator on a cycle-by-cycle basis.

  18. Study Modules for Calculus-Based General Physics. [Includes Modules 11-14: Collisions; Equilibrium of Rigid Bodies; Rotational Dynamics; and Fluid Mechanics].

    ERIC Educational Resources Information Center

    Fuller, Robert G., Ed.; And Others

    This is part of a series of 42 Calculus Based Physics (CBP) modules totaling about 1,000 pages. The modules include study guides, practice tests, and mastery tests for a full-year individualized course in calculus-based physics based on the Personalized System of Instruction (PSI). The units are not intended to be used without outside materials;…

  19. Effects of manipulating slowpoke calcium-dependent potassium channel expression on rhythmic locomotor activity in Drosophila larvae

    PubMed Central

    2013-01-01

    Rhythmic motor behaviors are generated by networks of neurons. The sequence and timing of muscle contractions depends on both synaptic connections between neurons and the neurons’ intrinsic properties. In particular, motor neuron ion currents may contribute significantly to motor output. Large conductance Ca2+-dependent K+ (BK) currents play a role in action potential repolarization, interspike interval, repetitive and burst firing, burst termination and interburst interval in neurons. Mutations in slowpoke (slo) genes encoding BK channels result in motor disturbances. This study examined the effects of manipulating slo channel expression on rhythmic motor activity using Drosophila larva as a model system. Dual intracellular recordings from adjacent body wall muscles were made during spontaneous crawling-related activity in larvae expressing a slo mutation or a slo RNA interference construct. The incidence and duration of rhythmic activity in slo mutants were similar to wild-type control animals, while the timing of the motor pattern was altered. slo mutants showed decreased burst durations, cycle durations, and quiescence intervals, and increased duty cycles, relative to wild-type. Expressing slo RNAi in identified motor neurons phenocopied many of the effects observed in the mutant, including decreases in quiescence interval and cycle duration. Overall, these results show that altering slo expression in the whole larva, and specifically in motor neurons, changes the frequency of crawling activity. These results suggest an important role for motor neuron intrinsic properties in shaping the timing of motor output. PMID:23638395

  20. Peripheral circadian oscillators and their rhythmic regulation.

    PubMed

    Fukuhara, Chiaki; Tosini, Gianluca

    2003-05-01

    Most of the organisms living on earth show 24 hour (circadian) rhythms that are endogenously controlled by biological clocks. In mammals, these rhythms are generated by the circadian pacemaker located in the suprachiasmatic nucleus (SCN) of the hypothalamus. However, recent studies have demonstrated that circadian oscillators can be found in many organs and tissues, and it appears that the circadian oscillators in the periphery are not self-sustained, since, in vitro, the oscillation disappears after a few cycles. Although analysis of the clockwork mechanism indicates that the molecular composition of the clock in the SCN and in the peripheral tissues is very similar, the mechanism responsible for the damping of the circadian oscillation in the periphery is unknown. Recent studies have also indicated that the mammalian circadian system is hierarchically organized in that the SCN (i.e., the master circadian pacemaker) controls the peripheral oscillators in order to coordinate the physiological events in an entire body. The mechanisms by which the SCN controls peripheral oscillators are just starting to be elucidated. The aim of this review is to summarize the most recent findings on functioning of these extra-SCN oscillators and the mechanisms the SCN controls peripheral oscillators.

  1. Perceptual tests of rhythmic similarity: I. Mora rhythm.

    PubMed

    Murty, Lalita; Otake, Takashi; Cutler, Anne

    2007-01-01

    Listeners rely on native-language rhythm in segmenting speech; in different languages, stress-, syllable- or mora-based rhythm is exploited. The rhythmic similarity hypothesis holds that where two languages have similar rhythm, listeners of each language should segment their own and the other language similarly. Such similarity in listening was previously observed only for related languages (English-Dutch; French-Spanish). We now report three experiments in which speakers of Telugu, a Dravidian language unrelated to Japanese but similar to it in crucial aspects of rhythmic structure, heard speech in Japanese and in their own language, and Japanese listeners heard Telugu. For the Telugu listeners, detection of target sequences in Japanese speech was harder when target boundaries mismatched mora boundaries, exactly the pattern that Japanese listeners earlier exhibited with Japanese and other languages. The same results appeared when Japanese listeners heard Telugu speech containing only codas permissible in Japanese. Telugu listeners' results with Telugu speech were mixed, but the overall pattern revealed correspondences between the response patterns of the two listener groups, as predicted by the rhythmic similarity hypothesis. Telugu and Japanese listeners appear to command similar procedures for speech segmentation, further bolstering the proposal that aspects of language phonological structure affect listeners' speech segmentation.

  2. Auditory evoked responses to rhythmic sound pulses in dolphins.

    PubMed

    Popov, V V; Supin, A Y

    1998-10-01

    The ability of auditory evoked potentials to follow sound pulse (click or pip) rate was studied in bottlenosed dolphins. Sound pulses were presented in 20-ms rhythmic trains separated by 80-ms pauses. Rhythmic click or pip trains evoked a quasi-sustained response consisting of a sequence of auditory brainstem responses. This was designated as the rate-following response. Rate following response peak-to-peak amplitude dependence on sound pulse rate was almost flat up to 200 s-1, then displayed a few peaks and valleys superimposed on a low-pass filtering function with a cut-off frequency of 1700 s-1 at a 0.1-amplitude level. Peaks and valleys of the function corresponded to the pattern of the single auditory brain stem response spectrum; the low-pass cut-off frequency was below the auditory brain stem response spectrum bandwidth. Rate-following response frequency composition (magnitudes of the fundamental and harmonics) corresponded to the auditory brain stem response frequency spectrum except for lower fundamental magnitudes at frequencies above 1700 Hz. These regularities were similar for both click and pip trains. The rate-following response to steady-state rhythmic stimulation was similar to the rate-following response evoked by short trains except for a slight amplitude decrease with the rate increase above 10 s-1. The latter effect is attributed to a long-term rate-dependent adaptation in conditions of the steady-state pulse stimulation.

  3. ACE and AGTR1 polymorphisms in elite rhythmic gymnastics.

    PubMed

    Di Cagno, Alessandra; Sapere, Nadia; Piazza, Marina; Aquino, Giovanna; Iuliano, Enzo; Intrieri, Mariano; Calcagno, Giuseppe

    2013-02-01

    In the angiotensin-converting enzyme (ACE) gene, Alu deletion, in intron 16, is associated with higher concentrations of ACE serum activity and this may be associated with elite sprint and power performance. The Alu insertion is associated with lower ACE levels and this could lead to endurance performance. Moreover, recent studies have identified a single-nucleotide polymorphism of the angiotensin type 1 receptor gene AGTR1, which seems to be related to ACE activity. The aim of this study was to examine the involvement of the ACE and the AGTR1 gene polymorphisms in 28 Italian elite rhythmic gymnasts (age range 21 ± 7.6 years), and compare them to 23 middle level rhythmic gymnasts (age range 17 ± 10.9 years). The ACE D allele was significantly more frequent in elite athletes than in the control population (χ(2)=4.07, p=0.04). Comparisons between the middle level and elite athletes revealed significant differences (p<0.0001) for the ACE DD genotype (OR=6.48, 95% confidence interval=1.48-28.34), which was more frequent in elite athletes. There were no significant differences in the AGTR1 A/C genotype or allele distributions between the middle level and elite athletes. In conclusion, the ACE D allele genotype could be a contributing factor to high-performance rhythmic gymnastics that should be considered in athlete development and could help to identify which skills should be trained for talent promotion.

  4. Auditory rhythmic cueing in movement rehabilitation: findings and possible mechanisms

    PubMed Central

    Schaefer, Rebecca S.

    2014-01-01

    Moving to music is intuitive and spontaneous, and music is widely used to support movement, most commonly during exercise. Auditory cues are increasingly also used in the rehabilitation of disordered movement, by aligning actions to sounds such as a metronome or music. Here, the effect of rhythmic auditory cueing on movement is discussed and representative findings of cued movement rehabilitation are considered for several movement disorders, specifically post-stroke motor impairment, Parkinson's disease and Huntington's disease. There are multiple explanations for the efficacy of cued movement practice. Potentially relevant, non-mutually exclusive mechanisms include the acceleration of learning; qualitatively different motor learning owing to an auditory context; effects of increased temporal skills through rhythmic practices and motivational aspects of musical rhythm. Further considerations of rehabilitation paradigm efficacy focus on specific movement disorders, intervention methods and complexity of the auditory cues. Although clinical interventions using rhythmic auditory cueing do not show consistently positive results, it is argued that internal mechanisms of temporal prediction and tracking are crucial, and further research may inform rehabilitation practice to increase intervention efficacy. PMID:25385780

  5. Beats produced between a rhythmic applied force and the resting tremor of Parkinsonism.

    PubMed

    Walsh, E G

    1979-01-01

    Rhythmic forces have been applied to the wrist of patients with Parkinsonism tremor by means of a printed motor. The tremor rate was not altered to that of the applied force. On the contrary, beats were established, the rate of which depended on the difference in rate between the tremor and the applied rhythm. Most of the observations have been for horizontal motion of the hand but similar phenomena have been seen for vertical movements, and for other parts of the body--for example, foot, elbow, finger joint, and head. The observations are regarded as supporting the view that the tremorgenic mechanism is central. There was no electromyographic evidence of servo driving or servo assistance in the genesis of the tremor.

  6. Intensity-Modulated Radiotherapy-Based Stereotactic Body Radiotherapy for Medically Inoperable Early-Stage Lung Cancer: Excellent Local Control

    SciTech Connect

    Videtic, Gregory M.M.; Stephans, Kevin; Reddy, Chandana; Gajdos, Stephen; Kolar, Matthew; Clouser, Edward; Djemil, Toufik

    2010-06-01

    Purpose: To validate the use of stereotactic body radiotherapy (SBRT) using intensity-modulated radiotherapy (IMRT) beams for medically inoperable Stage I lung cancer. Methods and Materials: From February 2004 to November 2006, a total of 26 patients with 28 lesions received SBRT using a Novalis/BrainLAB system. Immobilization involved a Bodyfix vacuum cushion. A weighted abdominal belt limited respiratory excursion. Computed tomographic simulation images were acquired at rest, full inhalation, and full exhalation and were merged to generate an internal gross tumor volume (ITV). Dose was prescribed to cover the planning target volume (PTV), defined as PTV = ITV + 3-5 mm set-up margin. Heterogeneity corrections were used. Delivery of 50 Gy in five sequential fractions typically used seven nonopposing, noncoplanar beams. Image-guided target verification was provided by BrainLAB-ExacTrac. Results: Among the 26 patients, the mean age was 74 years (range, 49-88 years). Of the patients, 50% were male and 50% female. The median Karnofsky performance status was 70 (range, 40-100). The median follow-up was 30.9 months (range, 10.4-51.4 months). Tissue diagnosis was contraindicated in seven patients (26.9%). There were 22 T1 (78.6%) and six T2 (21.4%) tumors. The median conformality index was 1.38 (range, 1.12-1.8). The median heterogeneity index was 1.08 (range, 1.04-1.2). One patient (3.6%) developed acute Grade 3 dyspnea and one patient developed late Grade 2 chest wall pain. Actuarial local control and overall survival at 3 years were 94.4% and 52%, respectively. Conclusions: Use of IMRT-based delivery of SBRT using restriction of tumor motion in medically inoperable lung cancer demonstrates excellent local control and favorable survival.

  7. Optimal planning strategy among various arc arrangements for prostate stereotactic body radiotherapy with volumetric modulated arc therapy technique

    PubMed Central

    Kang, Sang Won; Kim, Jae Sung; Kim, In Ah; Eom, Keun Yong; Song, Changhoon; Lee, Jeong Woo; Kim, Jin Young

    2017-01-01

    Abstract Background The aim of this study was to determine the optimal strategy among various arc arrangements in prostate plans of stereotactic body radiotherapy with volumetric modulated arc therapy (SBRT-VMAT). Patients and methods To investigate how arc arrangements affect dosimetric and biological metrics, SBRT-VMAT plans for eighteen patients were generated with arrangements of single-full arc (1FA), single-partial arc (1PA), double-full arc (2FA), and double-partial arc (2PA). All plans were calculated by the Acuros XB calculation algorithm. Dosimetric and radiobiological metrics for target volumes and organs at risk (OARs) were evaluated from dosevolume histograms. Results All plans were highly conformal (CI<1.05, CN=0.91) and homogeneous (HI=0.09-0.12) for target volumes. For OARs, there was no difference in the bladder dose, while there was a significant difference in the rectum and both femoral head doses. Plans using 1PA and 2PA showed a strong reduction to the mean rectum dose compared to plans using 1FA and 2FA. Contrastively, the D2% and mean dose in both femoral heads were always lower in plans using 1FA and 2FA. The average tumor control probability and normal tissue complication probability were comparable in plans using all arc arrangements. Conclusions The use of 1PA had a more effective delivery time and produced equivalent target coverage with better rectal sparing, although all plans using four arc arrangements showed generally similar for dosimetric and biological metrics. However, the D2% and mean dose in femoral heads increased slightly and remained within the tolerance. Therefore, this study suggests that the use of 1PA is an attractive choice for delivering prostate SBRT-VMAT. PMID:28265240

  8. Saturated fat intake modulates the association between an obesity genetic risk score and body mass index in two US populations.

    PubMed

    Casas-Agustench, Patricia; Arnett, Donna K; Smith, Caren E; Lai, Chao-Qiang; Parnell, Laurence D; Borecki, Ingrid B; Frazier-Wood, Alexis C; Allison, Matthew; Chen, Yii-Der Ida; Taylor, Kent D; Rich, Stephen S; Rotter, Jerome I; Lee, Yu-Chi; Ordovás, José M

    2014-12-01

    Combining multiple genetic variants related to obesity into a genetic risk score (GRS) might improve identification of individuals at risk of developing obesity. Moreover, characterizing gene-diet interactions is a research challenge to establish dietary recommendations to individuals with higher predisposition to obesity. Our objective was to analyze the association between an obesity GRS and body mass index (BMI) in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) population, focusing on gene-diet interactions with total fat and saturated fatty acid (SFA) intake, and to replicate findings in the Multi-Ethnic Study of Atherosclerosis (MESA) population. Cross-sectional analyses included 783 white US participants from GOLDN and 2,035 from MESA. Dietary intakes were estimated with validated food frequency questionnaires. Height and weight were measured. A weighted GRS was calculated on the basis of 63 obesity-associated variants. Multiple linear regression models adjusted by potential confounders were used to examine gene-diet interactions between dietary intake (total fat and SFA) and the obesity GRS in determining BMI. Significant interactions were found between total fat intake and the obesity GRS using these variables as continuous for BMI (P for interaction=0.010, 0.046, and 0.002 in GOLDN, MESA, and meta-analysis, respectively). These association terms were stronger when assessing interactions between SFA intake and GRS for BMI (P for interaction=0.005, 0.018, and <0.001 in GOLDN, MESA, and meta-analysis, respectively). SFA intake interacts with an obesity GRS in modulating BMI in two US populations. Although determining the causal direction requires further investigation, these findings suggest that potential dietary recommendations to reduce BMI effectively in populations with high obesity GRS would be to reduce total fat intake mainly by limiting SFAs.

  9. Postsynaptic action of GABA in modulating sensory transmission in co-cultures of rat carotid body via GABAA receptors

    PubMed Central

    Zhang, Min; Clarke, Katherine; Zhong, Huijun; Vollmer, Cathy; Nurse, Colin A

    2009-01-01

    GABA is expressed in carotid body (CB) chemoreceptor type I cells and has previously been reported to modulate sensory transmission via presynaptic GABAB receptors. Because low doses of clinically important GABAA receptor (GABAAR) agonists, e.g. benzodiazepines, have been reported to depress afferent CB responses to hypoxia, we investigated the potential contribution of GABAAR in co-cultures of rat type I cells and sensory petrosal neurones (PNs). During gramicidin perforated-patch recordings (to preserve intracellular Cl−), GABA and/or the GABAA agonist muscimol (50 μm) induced a bicuculline-sensitive membrane depolarization in isolated PNs. GABA-induced whole-cell currents reversed at ∼−38 mV and had an EC50 of ∼10 μm (Hill coefficient =∼1) at −60 mV. During simultaneous PN and type I cell recordings at functional chemosensory units in co-culture, bicuculline reversibly potentiated the PN, but not type I cell, depolarizing response to hypoxia. Application of the CB excitatory neurotransmitter ATP (1 μm) over the soma of functional PN induced a spike discharge that was markedly suppressed during co-application with GABA (2 μm), even though GABA alone was excitatory. RT-PCR analysis detected expression of GABAergic markers including mRNA for α1, α2, β2, γ2S, γ2L and γ3 GABAAR subunits in petrosal ganglia extracts. Also, CB extracts contained mRNAs for GABA biosynthetic markers, i.e. glutamate decarboxylase (GAD) isoforms GAD 67A,E, and GABA transporter isoforms GAT 2,3 and BGT-1. In CB sections, sensory nerve endings apposed to type I cells were immunopositive for the GABAAR β subunit. These data suggest that GABA, released from the CB during hypoxia, inhibits sensory discharge postsynaptically via a shunting mechanism involving GABAA receptors. PMID:19029183

  10. Restricted feeding restores rhythmicity in the pineal gland of arrhythmic suprachiasmatic-lesioned rats.

    PubMed

    Feillet, Céline A; Mendoza, Jorge; Pévet, Paul; Challet, Etienne

    2008-12-01

    In mammals, the rhythmic synthesis of melatonin by the pineal gland is tightly controlled by the master clock located in the suprachiasmatic nuclei (SCN). In behaviourally arrhythmic SCN-lesioned rats, we investigated the effects of daily restricted feeding (RF) on pineal melatonin synthesis. RF restored not only a rhythmic transcription of the rate-limiting enzyme for melatonin biosynthesis [arylalkylamine-N-acetyltransferase (AANAT)] and a rhythmic expression of c-FOS but also a rhythmic synthesis of melatonin in the pineal gland. In control rats without functional SCN and fed ad libitum, a daily immobilization stress did not restore any rhythmicity in the pineal gland. Interestingly, a combination of RF and daily stress prior to the time of food access did not markedly impair AaNat mRNA and c-FOS rhythmicity but did abolish the restoration of rhythmic pineal melatonin. These data indicate that the synchronizing effects of RF on the pineal rhythmicity are not due to, and cannot be mimicked by, high levels of circulating glucocorticoids. In keeping with the multi-oscillatory nature of the circadian system, the rhythmicity of pineal melatonin in mammals, until now an exclusive output of the SCN, can also be controlled by daily feeding cues when the SCN clock is lacking. Thus, the present study demonstrates that daily RF in SCN-lesioned rats provides, probably via sympathetic fibres, synchronizing stimuli strong enough to drive rhythmicity in the pineal gland.

  11. Circadian deep sequencing reveals stress-response genes that adopt robust rhythmic expression during aging

    PubMed Central

    Kuintzle, Rachael C.; Chow, Eileen S.; Westby, Tara N.; Gvakharia, Barbara O.; Giebultowicz, Jadwiga M.; Hendrix, David A

    2017-01-01

    Disruption of the circadian clock, which directs rhythmic expression of numerous output genes, accelerates aging. To enquire how the circadian system protects aging organisms, here we compare circadian transcriptomes in heads of young and old Drosophila melanogaster. The core clock and most output genes remained robustly rhythmic in old flies, while others lost rhythmicity with age, resulting in constitutive over- or under-expression. Unexpectedly, we identify a subset of genes that adopted increased or de novo rhythmicity during aging, enriched for stress-response functions. These genes, termed late-life cyclers, were also rhythmically induced in young flies by constant exposure to exogenous oxidative stress, and this upregulation is CLOCK-dependent. We also identify age-onset rhythmicity in several putative primary piRNA transcripts overlapping antisense transposons. Our results suggest that, as organisms age, the circadian system shifts greater regulatory priority to the mitigation of accumulating cellular stress. PMID:28221375

  12. Critical Appraisal of Volumetric Modulated Arc Therapy in Stereotactic Body Radiation Therapy for Metastases to Abdominal Lymph Nodes

    SciTech Connect

    Bignardi, Mario; Cozzi, Luca; Fogliata, Antonella; Lattuada, Paola; Mancosu, Pietro; Navarria, Piera; Urso, Gaetano; Vigorito, Sabrina; Scorsetti, Marta

    2009-12-01

    Purpose: A planning study was performed comparing volumetric modulated arcs, RapidArc (RA), fixed beam IMRT (IM), and conformal radiotherapy (CRT) with multiple static fields or short conformal arcs in a series of patients treated with hypofractionated stereotactic body radiation therapy (SBRT) for solitary or oligo-metastases from different tumors to abdominal lymph nodes. Methods and Materials: Fourteen patients were included in the study. Dose prescription was set to 45 Gy (mean dose to clinical target volume [CTV]) in six fractions of 7.5 Gy. Objectives for CTV and planning target volume (PTV) were as follows: Dose{sub min} >95%, Dose{sub max} <107%. For organs at risk the following objectives were used: Maximum dose to spine <18 Gy; V{sub 15Gy} <35% for both kidneys, V{sub 36Gy} <1% for duodenum, V{sub 36Gy} <3% for stomach and small bowel, V{sub 15Gy} <(total liver volume - 700 cm{sup 3}) for liver. Dose-volume histograms were evaluated to assess plan quality. Results: Planning objectives on CTV and PTV were achieved by all techniques. Use of RA improved PTV coverage (V{sub 95%} = 90.2% +- 5.2% for RA compared with 82.5% +- 9.6% and 84.5% +- 8.2% for CRT and IM, respectively). Most planning objectives for organs at risk were met by all techniques except for the duodenum, small bowel, and stomach, in which the CRT plans exceeded the dose/volume constraints in some patients. The MU/fraction values were as follows: 2186 +- 211 for RA, 2583 +- 699 for IM, and 1554 +- 153 for CRT. Effective treatment time resulted as follows: 3.7 +- 0.4 min for RA, 10.6 +- 1.2 min for IM, and 6.3 +- 0.5 min for CRT. Conclusions: Delivery of SBRT by RA showed improvements in conformal avoidance with respect to standard conformal irradiation. Delivery parameters confirmed logistical advantages of RA, particularly compared with IM.

  13. Bodily ownership modulation in defensive responses: physiological evidence in brain-damaged patients with pathological embodiment of other’s body parts

    PubMed Central

    Fossataro, C.; Gindri, P.; Mezzanato, T.; Pia, L.; Garbarini, F.

    2016-01-01

    Do conscious beliefs about the body affect defensive mechanisms within the body? To answer this question we took advantage from a monothematic delusion of bodily ownership, in which brain-damaged patients misidentify alien limbs as their own. We investigated whether the delusional belief that an alien hand is their own hand modulates a subcortical defensive response, such as the hand-blink reflex. The blink, dramatically increases when the threated hand is inside the defensive peripersonal-space of the face. In our between-subjects design, including patients and controls, the threat was brought near the face either by the own hand or by another person’s hand. Our results show an ownership-dependent modulation of the defensive response. In controls, as well as in the patients’ intact-side, the response enhancement is significantly greater when the threat was brought near the face by the own than by the alien hand. Crucially, in the patients’ affected-side (where the pathological embodiment occurs), the alien (embodied) hand elicited a response enhancement comparable to that found when the threat is brought near the face by the real hand. These findings suggest the existence of a mutual interaction between our conscious beliefs about the body and the physiological mechanisms within the body. PMID:27292285

  14. Sex Differences in Rhythmic Preferences in the Budgerigar (Melopsittacus undulatus): A Comparative Study with Humans

    PubMed Central

    Hoeschele, Marisa; Bowling, Daniel L.

    2016-01-01

    A variety of parrot species have recently gained attention as members of a small group of non-human animals that are capable of coordinating their movements in time with a rhythmic pulse. This capacity is highly developed in humans, who display unparalleled sensitivity to musical beats and appear to prefer rhythmically organized sounds in their music. Do parrots also exhibit a preference for rhythmic over arrhythmic sounds? Here, we presented humans and budgerigars (Melopsittacus undulatus) – a small parrot species that have been shown to be able to align movements with a beat – with rhythmic and arrhythmic sound patterns in an acoustic place preference paradigm. Both species were allowed to explore an environment for 5 min. We quantified how much time they spent in proximity to rhythmic vs. arrhythmic stimuli. The results show that humans spent more time with rhythmic stimuli, and also preferred rhythmic stimuli when directly asked in a post-test survey. Budgerigars did not show any such overall preferences. However, further examination of the budgerigar results showed an effect of sex, such that male budgerigars spent more time with arrthymic stimuli, and female budgerigars spent more time with rhythmic stimuli. Our results support the idea that rhythmic information is interesting to budgerigars. We suggest that future investigations into the temporal characteristics of naturalistic social behaviors in budgerigars, such as courtship vocalizations and head-bobbing displays, may help explain the sex difference we observed. PMID:27757099

  15. Tectonic tremor on Vancouver Island, Cascadia, modulated by the body and surface waves of the Mw 8.6 and 8.2, 2012 East Indian Ocean earthquakes

    NASA Astrophysics Data System (ADS)

    Kundu, Bhaskar; Ghosh, Abhijit; Mendoza, Manuel; Bürgmann, Roland; Gahalaut, V. K.; Saikia, Dipankar

    2016-09-01

    The 2012 East Indian Ocean earthquake (Mw 8.6), so far the largest intraoceanic plate strike-slip event ever recorded, modulated tectonic tremors in the Cascadia subduction zone. The rate of tremor activity near Vancouver Island increased by about 1.5 times from its background level during the passage of seismic waves of this earthquake. In most cases of dynamic modulation, large-amplitude and long-period surface waves stimulate tremors. However, in this case even the small stress change caused by body waves generated by the 2012 earthquake modulated tremor activity. The tremor modulation continued during the passage of the surface waves, subsequent to which the tremor activity returned to background rates. Similar tremor modulation is observed during the passage of the teleseismic waves from the Mw 8.2 event, which occurs about 2 h later near the Mw 8.6 event. We show that dynamic stresses from back-to-back large teleseismic events can strongly influence tremor sources.

  16. Forearm training attenuates sympathetic responses to prolonged rhythmic forearm exercise

    NASA Technical Reports Server (NTRS)

    Sinoway, L.; Shenberger, J.; Leaman, G.; Zelis, R.; Gray, K.; Baily, R.; Leuenberger, U.

    1996-01-01

    We previously demonstrated that nonfatiguing rhythmic forearm exercise at 25% maximal voluntary contraction (12 2-s contractions/min) evokes sympathoexcitation without significant engagement of metabolite-sensitive muscle afferents (B.A. Batman, J.C. Hardy, U.A. Leuenberger, M.B. Smith, Q.X. Yang and L.I. Sinoway. J. Appl. Physiol. 76: 1077-1081, 1994). This is in contrast to the sympathetic nervous system responses observed during fatiguing static forearm exercise where metabolite-sensitive afferents are the key determinants of sympathetic activation. In this report we examined whether forearm exercise training would attenuate sympathetic nervous system responses to rhythmic forearm exercise. We measured heart rate, mean arterial blood pressure (MAP), muscle sympathetic nerve activity (microneurography), plasma norepinephrine (NE), and NE spillover and clearance (tritiated NE kinetics) during nonfatiguing rhythmic forearm exercise before and after a 4-wk unilateral forearm training paradigm. Training had no effect on forearm mass, maximal voluntary contraction, or heart rate but did attenuate the increase in MAP (increase in MAP: from 15.2 +/- 1.8 before training to 11.4 +/- 1.4 mmHg after training; P < 0.017), muscle sympathetic nerve activity (increase in bursts: from 10.8 +/- 1.4 before training to 6.2 +/- 1.1 bursts/min after training; P < 0.030), and the NE spillover (increases in arterial spillover: from 1.3 +/- 0.2 before training to 0.6 +/- 0.2 nmol.min-1.m-2 after training, P < 0.014; increase in venous spillover: from 2.0 +/- 0.6 before training to 1.0 +/- 0.5 nmol.min-1.m-2 after training, P < 0.037) seen in response to exercise performed by the trained forearm. Thus forearm training reduces sympathetic responses during a nonfatiguing rhythmic handgrip paradigm that does not engage muscle metaboreceptors. We speculate that this effect is due to a conditioning-induced reduction in mechanically sensitive muscle afferent discharge.

  17. Sodium Leak Channels in Neuronal Excitability and Rhythmic Behaviors

    PubMed Central

    Ren, Dejian

    2011-01-01

    Extracellular K+, Na+, and Ca2+ ions all influence the resting membrane potential of the neuron. However, the mechanisms by which extracellular Na+ and Ca2+ regulate basal neuronal excitability are not well understood. Recent findings suggest that NALCN, in association with UNC79 and UNC80, contributes a basal Na+ leak conductance in neurons. Mutations in Nalcn, Unc79, or Unc80 lead to severe phenotypes that include neonatal lethality and disruption in rhythmic behaviors. This review discusses the properties of the NALCN complex, its regulation, and its contribution to neuronal function and animal behavior. PMID:22196327

  18. Effect of rhythmic attention on the segregation of interleaved melodies.

    PubMed

    Devergie, Aymeric; Grimault, Nicolas; Tillmann, Barbara; Berthommier, Frédéric

    2010-07-01

    As previously suggested, attention may increase segregation via enhancement and suppression sensory mechanisms. To test this hypothesis, we proposed an interleaved melody paradigm with two rhythm conditions applied to familiar target melodies and unfamiliar distractor melodies sharing pitch and timbre properties. When rhythms of both target and distractor were irregular, target melodies were identified above chance level. A sensory enhancement mechanism guided by listeners' knowledge may have helped to extract targets from the interleaved sequence. When the distractor was rhythmically regular, performance was increased, suggesting that the distractor may have been suppressed by a sensory suppression mechanism.

  19. Finding the dimension of slow dynamics in a rhythmic system

    PubMed Central

    Revzen, Shai; Guckenheimer, John M.

    2012-01-01

    Dynamical systems with asymptotically stable periodic orbits are generic models for rhythmic processes in dissipative physical systems. This paper presents a method for reconstructing the dynamics near a periodic orbit from multivariate time-series data. It is used to test theories about the control of legged locomotion, a context in which time series are short when compared with previous work in nonlinear time-series analysis. The method presented here identifies appropriate dimensions of reduced order models for the deterministic portion of the dynamics. The paper also addresses challenges inherent in identifying dynamical models with data from different individuals. PMID:21937489

  20. Champagne experiences various rhythmical bubbling regimes in a flute.

    PubMed

    Liger-Belair, Gérard; Tufaile, Alberto; Jeandet, Philippe; Sartorelli, José-Carlos

    2006-09-20

    Bubble trains are seen rising gracefully from a few points on the glass wall (called nucleation sites) whenever champagne is poured into a glass. As time passes during the gas-discharging process, the careful observation of some given bubble columns reveals that the interbubble distance may change suddenly, thus revealing different rhythmical bubbling regimes. Here, it is reported that the transitions between the different bubbling regimes of some nucleation sites during gas discharging is a process which may be ruled by a strong interaction between tiny gas pockets trapped inside the nucleation site and/or also by an interaction between the tiny bubbles just blown from the nucleation site.

  1. The role of clock genes and rhythmicity in the liver.

    PubMed

    Schmutz, I; Albrecht, U; Ripperger, J A

    2012-02-05

    The liver is the important organ to maintain energy homeostasis of an organism. To achieve this, many biochemical reactions run in this organ in a rhythmic fashion. An elegant way to coordinate the temporal expression of genes for metabolic enzymes relies in the link to the circadian timing system. In this fashion not only a maximum of synchronization is achieved, but also anticipation of daily recurring events is possible. Here we will focus on the input and output pathways of the hepatic circadian oscillator and discuss the recently found flexibility of its circadian transcriptional networks.

  2. Prior experience does not alter modulation of cutaneous reflexes during manual wheeling and symmetrical arm cycling.

    PubMed

    MacGillivray, Megan K; Klimstra, Marc; Sawatzky, Bonita; Zehr, E Paul; Lam, Tania

    2013-05-01

    Previous research has reported that training and experience influence H-reflex amplitude during rhythmic activity; however, little research has yet examined the influence of training on cutaneous reflexes. Manual wheelchair users (MWUs) depend on their arms for locomotion. We postulated that the daily dependence and high amount of use of the arms for mobility in MWUs would show differences in cutaneous reflex modulation during upper limb cyclic movements compared with able-bodied control subjects. We hypothesized that MWUs would demonstrate increased reflex response amplitudes for both manual wheeling and symmetrical arm cycling tasks. The superficial radial nerve was stimulated randomly at different points of the movement cycle of manual wheeling and symmetrical arm cycling in MWUs and able-bodied subjects naive to wheeling. Our results showed that there were no differences in amplitude modulation of early- or middle-latency cutaneous reflexes between the able-bodied group and the MWU group. However, there were several differences in amplitude modulation of cutaneous reflexes between tasks (manual wheeling and symmetrical arm cycling). Specifically, differences were observed in early-latency responses in the anterior and posterior deltoid muscles and biceps and triceps brachii as well as in middle-latency responses in the anterior and posterior deltoid. These data suggest that manual wheeling experience does not modify the pattern of cutaneous reflex amplitude modulation during manual wheeling. The differences in amplitude modulation of cutaneous reflexes between tasks may be a result of mechanical differences (i.e., hand contact) between tasks.

  3. The hepatic circadian clock modulates xenobiotic metabolism in mice.

    PubMed

    DeBruyne, Jason P; Weaver, David R; Dallmann, Robert

    2014-08-01

    The circadian clock generates daily cycles of gene expression that regulate physiological processes. The liver plays an important role in xenobiotic metabolism and also has been shown to possess its own cell-based clock. The liver clock is synchronized by the master clock in the brain, and a portion of rhythmic gene expression can be driven by behavior of the organism as a whole even when the hepatic clock is suppressed. So far, however, there is relatively little evidence indicating whether the liver clock is functionally important in modulating xenobiotic metabolism. Thus, mice lacking circadian clock function in the whole body or specifically in liver were challenged with pentobarbital and acetaminophen, and pentobarbital sleep time (PBST) and acetaminophen toxicity, respectively, was assessed at different times of day in mutant and control mice. The results suggest that the liver clock is essential for rhythmic changes in xenobiotic detoxification. Surprisingly, it seems that the way in which the clock is disrupted determines the rate of xenobiotic metabolism in the liver. CLOCK-deficient mice are remarkably resistant to acetaminophen and exhibit a longer PBST, while PERIOD-deficient mice have a short PBST. These results indicate an essential role of the tissue-intrinsic peripheral circadian oscillator in the liver in regulating xenobiotic metabolism.

  4. Perceptual tests of rhythmic similarity: II. Syllable rhythm.

    PubMed

    Kim, Jeesun; Davis, Chris; Cutler, Anne

    2008-01-01

    To segment continuous speech into its component words, listeners make use of language rhythm; because rhythm differs across languages, so do the segmentation procedures which listeners use. For each of stress-, syllable- and mora-based rhythmic structure, perceptual experiments have led to the discovery of corresponding segmentation procedures. In the case of mora-based rhythm, similar segmentation has been demonstrated in the otherwise unrelated languages Japanese and Telugu; segmentation based on syllable rhythm, however, has been previously demonstrated only for European languages from the Romance family. We here report two target detection experiments in which Korean listeners, presented with speech in Korean and in French, displayed patterns of segmentation like those previously observed in analogous experiments with French listeners. The Korean listeners' accuracy in detecting word-initial target fragments in either language was significantly higher when the fragments corresponded exactly to a syllable in the input than when the fragments were smaller or larger than a syllable. We conclude that Korean and French listeners can call on similar procedures for segmenting speech, and we further propose that perceptual tests of speech segmentation provide a valuable accompaniment to acoustic analyses for establishing languages' rhythmic class membership.

  5. Rhythmic coordination of hippocampal neurons during associative memory processing

    PubMed Central

    Rangel, Lara M; Rueckemann, Jon W; Riviere, Pamela D; Keefe, Katherine R; Porter, Blake S; Heimbuch, Ian S; Budlong, Carl H; Eichenbaum, Howard

    2016-01-01

    Hippocampal oscillations are dynamic, with unique oscillatory frequencies present during different behavioral states. To examine the extent to which these oscillations reflect neuron engagement in distinct local circuit processes that are important for memory, we recorded single cell and local field potential activity from the CA1 region of the hippocampus as rats performed a context-guided odor-reward association task. We found that theta (4–12 Hz), beta (15–35 Hz), low gamma (35–55 Hz), and high gamma (65–90 Hz) frequencies exhibited dynamic amplitude profiles as rats sampled odor cues. Interneurons and principal cells exhibited unique engagement in each of the four rhythmic circuits in a manner that related to successful performance of the task. Moreover, principal cells coherent to each rhythm differentially represented task dimensions. These results demonstrate that distinct processing states arise from the engagement of rhythmically identifiable circuits, which have unique roles in organizing task-relevant processing in the hippocampus. DOI: http://dx.doi.org/10.7554/eLife.09849.001 PMID:26751780

  6. Circadian rhythmicity of synapses in mouse somatosensory cortex.

    PubMed

    Jasinska, Malgorzata; Grzegorczyk, Anna; Woznicka, Olga; Jasek, Ewa; Kossut, Malgorzata; Barbacka-Surowiak, Grazyna; Litwin, Jan A; Pyza, Elzbieta

    2015-10-01

    The circadian rhythmicity displayed by motor behavior of mice: activity at night and rest during the day; and the associated changes in the sensory input are reflected by cyclic synaptic plasticity in the whisker representations located in the somatosensory (barrel) cortex. It was not clear whether diurnal rhythmic changes in synapse density previously observed in the barrel cortex resulted from changes in the activity of the animals, from daily light/dark (LD) rhythm or are driven by an endogenous clock. These changes were investigated in the barrel cortex of C57BL/6 mouse strain kept under LD 12 : 12 h conditions and in constant darkness (DD). Stereological analysis of serial electron microscopic sections was used to assess numerical density of synapses. In mice kept under LD conditions, the total density of synapses and the density of excitatory synapses located on dendritic spines was higher during the light period (rest phase). In contrast, the density of inhibitory synapses located on dendritic spines increased during the dark period (activity phase). Under DD conditions, the upregulation of the inhibitory synapses during the activity phase was retained, but the cyclic changes in the density of excitatory synapses were not observed. The results show that the circadian plasticity concerns only synapses located on spines (and not those on dendritic shafts), and that excitatory and inhibitory synapses are differently regulated during the 24 h cycle: the excitatory synapses are influenced by light, whilst the inhibitory synapses are driven by the endogenous circadian clock.

  7. Age effects in discrimination of intervals within rhythmic tone sequences

    PubMed Central

    Fitzgibbons, Peter J.; Gordon-Salant, Sandra

    2015-01-01

    This study measured listener sensitivity to increments of a target inter-onset interval (IOI) embedded within tone sequences that featured different rhythmic patterns. The sequences consisted of six 50-ms 1000-Hz tone bursts separated by silent intervals that were adjusted to create different timing patterns. Control sequences were isochronous, with all tonal IOIs fixed at either 200 or 400 ms, while other patterns featured combinations of the two IOIs arranged to create different sequential tonal groupings. Duration difference limens in milliseconds for increments of a single sequence IOI were measured adaptively by adjusting the duration of an inter-tone silent interval. Specific target IOIs within sequences differed across discrimination conditions. Listeners included younger normal-hearing adults and groups of older adults with and without hearing loss. Discrimination performance measured for each of the older groups of listeners was observed to be equivalent, with each group exhibiting significantly poorer discrimination performance than the younger listeners in each sequence condition. Additionally, the specific influence of variable rhythmic grouping on temporal sensitivity was found to be greatest among older listeners. PMID:25618068

  8. Metabolic rate: its circadian rhythmicity in the female domestic fowl.

    PubMed Central

    Berman, A; Meltzer, A

    1978-01-01

    1. In quasi-natural cyclic lighting, a circadian rhythm was observed in seven fowls; the range of oscillation of the rhythm was 50% of the mean metabolic level. Little variation was present between the individuals. 2. In fowls maintained for 15 days in isolation under 700 lx (ten fowls) or 0.07 lx (four fowls) constant lighting and at constant temperature free-running rhythms were evident; the range of oscillation was about 12% of the mean level. Large variation prevailed between the individuals in the range of oscillation and in the portion of variance accounted for by periodic regression. In dim light, rhythmicity declined to become non-significant by 8 days of exposure. 3. In four fowls maintained in a 6L/6D regimen for 12 days, metabolic rate was entrained to an ahemeral rhythm; there was no evidence of circadian influence on the metabolic response to light. Little variation was present between the individuals. Rhythmicity was maintained over the experimental period. 4. Metabolic levels were similar on 0.07 lx, 700 lx constant light, during the dark phase of the 6L/6D regimen and during night time in the quasi-natural cyclic lighting. They were also similar on the light phase of the 6L/6D regimen and the quasi-natural lighting. PMID:722545

  9. On the use of volumetric-modulated arc therapy for single-fraction thoracic vertebral metastases stereotactic body radiosurgery.

    PubMed

    Pokhrel, Damodar; Sood, Sumit; McClinton, Christopher; Shen, Xinglei; Badkul, Rajeev; Jiang, Hongyu; Mallory, Matthew; Mitchell, Mellissa; Wang, Fen; Lominska, Christopher

    2017-01-01

    To retrospectively evaluate quality, efficiency, and delivery accuracy of volumetric-modulated arc therapy (VMAT) plans for single-fraction treatment of thoracic vertebral metastases using image-guided stereotactic body radiosurgery (SBRS) after RTOG 0631 dosimetric compliance criteria. After obtaining credentialing for MD Anderson spine phantom irradiation validation, 10 previously treated patients with thoracic vertebral metastases with noncoplanar hybrid arcs using 1 to 2 3D-conformal partial arcs plus 7 to 9 intensity-modulated radiation therapy beams were retrospectively re-optimized with VMAT using 3 full coplanar arcs. Tumors were located between T2 and T12. Contrast-enhanced T1/T2-weighted magnetic resonance images were coregistered with planning computed tomography and planning target volumes (PTV) were between 14.4 and 230.1cc (median = 38.0cc). Prescription dose was 16Gy in 1 fraction with 6MV beams at Novalis-TX linear accelerator consisting of micro multileaf collimators. Each plan was assessed for target coverage using conformality index, the conformation number, the ratio of the volume receiving 50% of the prescription dose over PTV, R50%, homogeneity index (HI), and PTV_1600 coverage per RTOG 0631 requirements. Organs-at-risk doses were evaluated for maximum doses to spinal cord (D0.03cc, D0.35cc), partial spinal cord (D10%), esophagus (D0.03cc and D5cc), heart (D0.03cc and D15cc), and lung (V5, V10, and maximum dose to 1000cc of lung). Dose delivery efficiency and accuracy of each VMAT-SBRS plan were assessed using quality assurance (QA) plan on MapCHECK device. Total beam-on time was recorded during QA procedure, and a clinical gamma index (2%/2mm and 3%/3mm) was used to compare agreement between planned and measured doses. All 10 VMAT-SBRS plans met RTOG 0631 dosimetric requirements for PTV coverage. The plans demonstrated highly conformal and homogenous coverage of the vertebral PTV with mean HI, conformality index, conformation number, and R50

  10. [The model of geometrical human body phantom for calculating tissue doses in the service module of the International Space Station].

    PubMed

    Bondarenko, V A; Mitrikas, V G

    2007-01-01

    The model of a geometrical human body phantom developed for calculating the shielding functions of representative points of the body organs and systems is similar to the anthropomorphic phantom. This form of phantom can be integrated with the shielding model of the ISS Russian orbital segment to make analysis of radiation loading of crewmembers in different compartments of the vehicle. Calculation of doses absorbed by the body systems in terms of the representative points makes it clear that doses essentially depend on the phantom spatial orientation (eye direction). It also enables the absorbed dose evaluation from the shielding functions as the mean of the representative points and phantom orientation.

  11. Effect of rhythmic photostimulation on monkeys with hyperkinesis of post-encephalitic genesis

    NASA Technical Reports Server (NTRS)

    Danilov, I. V.; Kudrayatseva, N. N.

    1979-01-01

    In hyperkinetic monkeys a response opposite to that of healthy monkeys was observed during rhythmic photostimulation (frequency 3, 9, 18, 20, and 25/sec), i.e., the hyperkinesis disappeared. The significance of rhythmic excitatory cycles for interconnections between different brain structures is discussed.

  12. Motor Performance and Rhythmic Perception of Children with Intellectual and Developmental Disability and Developmental Coordination Disorder

    ERIC Educational Resources Information Center

    Kartasidou, Lefkothea; Varsamis, Panagiotis; Sampsonidou, Anna

    2012-01-01

    Professionals who work with children presenting intellectual and developmental disability (IDD) and developmental coordination disorder (DCD) are concerned with their motor development and their rhythmic perception. The aim of this study is to investigate the correlation between a motor performance test and a music rhythmic test that measures…

  13. Dietary Habits and Physical Self-Concept of Elite Rhythmic Gymnasts

    ERIC Educational Resources Information Center

    Boros, Szilvia

    2009-01-01

    Study aim: To identify main differences in nutrient patterns, food preferences and physical self-concept between the world's elite rhythmic gymnasts and untrained controls. Material and methods: A group of elite rhythmic gymnasts (n = 103) aged 15-21 years volunteered to participate in the study during the 2003 World Championships in Rhythmic…

  14. Strength Recovery Following Rhythmic or Sustained Exercise as a Function of Time.

    ERIC Educational Resources Information Center

    Kearney, Jay T.

    The relative rates of strength recovery subsequent to bouts of rhythmic or sustained isometric exercise were investigated. The 72 undergraduates who served as subjects were tested seven times within the framework of a repeated measures design. Each testing session involved two bouts of either rhythmic or sustained isometric exercise separated by a…

  15. An Experiment Using Three Films in Rhythmical Gymnastics Using Hand Apparatus. Final Report.

    ERIC Educational Resources Information Center

    McLellan, Mary I.

    Three films were produced to serve as instructional aids in teaching the rhythmic gymnastic skills of performing with clubs, balls, and hoops. The content of the films was determined with the aid of specialists in rhythmic gymnastics. To evaluate the films as aids to instruction, 170 women enrolled in elementary physical education courses were…

  16. Rhythmic motor behavior of preambulatory motor impaired, Down syndrome and nondisabled children: a comparative analysis.

    PubMed

    MacLean, W E; Ellis, D N; Galbreath, H N; Halpern, L F; Baumeister, A A

    1991-06-01

    The developmental course of rhythmic motor behavior was followed longitudinally for three groups of preambulatory children--normally developing, Down syndrome, and those with profound motor impairment. The groups differed in chronological age but were comparable with respect to motor age. The motor impaired subjects displayed significantly less rhythmic motor behavior than the nondisabled and Down syndrome groups. In comparing particular subtypes of rhythmic motor behavior, differences were found in both the average number of bouts and duration of subtypes among the groups. Longitudinal analyses of the data over the entire observation period revealed that the rhythmic motor behavior of the children with Down syndrome was more similar to that exhibited by the nondisabled children than was the rhythmic motor behavior of the children with motor impairment. However, there was considerable variability among the groups in several particular subtypes.

  17. Parasitic nematode-induced modulation of body weight and associated metabolic dysfunction in mouse models of obesity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Obesity is associated with a chronic low grade inflammation characterized by high level of pro-inflammatory cytokines and mediators implicated in disrupted metabolic homeostasis. Parasitic nematode infection induces a polarized Th2 cytokine response and has been shown to modulate immune-based pathol...

  18. Influence of Tempo and Rhythmic Unit in Musical Emotion Regulation.

    PubMed

    Fernández-Sotos, Alicia; Fernández-Caballero, Antonio; Latorre, José M

    2016-01-01

    This article is based on the assumption of musical power to change the listener's mood. The paper studies the outcome of two experiments on the regulation of emotional states in a series of participants who listen to different auditions. The present research focuses on note value, an important musical cue related to rhythm. The influence of two concepts linked to note value is analyzed separately and discussed together. The two musical cues under investigation are tempo and rhythmic unit. The participants are asked to label music fragments by using opposite meaningful words belonging to four semantic scales, namely "Tension" (ranging from Relaxing to Stressing), "Expressiveness" (Expressionless to Expressive), "Amusement" (Boring to Amusing) and "Attractiveness" (Pleasant to Unpleasant). The participants also have to indicate how much they feel certain basic emotions while listening to each music excerpt. The rated emotions are "Happiness," "Surprise," and "Sadness." This study makes it possible to draw some interesting conclusions about the associations between note value and emotions.

  19. Clock Genes in Glia Cells: A Rhythmic History.

    PubMed

    Chi-Castañeda, Donají; Ortega, Arturo

    2016-10-01

    Circadian rhythms are periodic patterns in biological processes that allow the organisms to anticipate changes in the environment. These rhythms are driven by the suprachiasmatic nucleus (SCN), the master circadian clock in vertebrates. At a molecular level, circadian rhythms are regulated by the so-called clock genes, which oscillate in a periodic manner. The protein products of clock genes are transcription factors that control their own and other genes' transcription, collectively known as "clock-controlled genes." Several brain regions other than the SCN express circadian rhythms of clock genes, including the amygdala, the olfactory bulb, the retina, and the cerebellum. Glia cells in these structures are expected to participate in rhythmicity. However, only certain types of glia cells may be called "glial clocks," since they express PER-based circadian oscillators, which depend of the SCN for their synchronization. This contribution summarizes the current information about clock genes in glia cells, their plausible role as oscillators and their medical implications.

  20. How the brainstem controls orofacial behaviors comprised of rhythmic actions

    PubMed Central

    Moore, Jeffrey D.; Kleinfeld, David; Wang, Fan

    2014-01-01

    Mammals perform a multitude of well-coordinated orofacial behaviors such as breathing, sniffing, chewing, licking, swallowing, vocalizing, and in rodents, whisking. The coordination of these actions must occur without fault to prevent fatal blockages of the airway. Deciphering the neuronal circuitry that controls even a single action requires understanding the integration of sensory feedback and executive commands. A far greater challenge is to understand the coordination of multiple actions. Here we focus on brainstem circuits that drive rhythmic orofacial actions. We discuss three neural computational mechanisms that may enable circuits for different actions to operate without interfering with each other. We conclude with proposed experimental programs for delineating the neural control principles that have evolved to coordinate orofacial behaviors. PMID:24890196

  1. Rhythmic TMS Causes Local Entrainment of Natural Oscillatory Signatures

    PubMed Central

    Thut, Gregor; Veniero, Domenica; Romei, Vincenzo; Miniussi, Carlo; Schyns, Philippe; Gross, Joachim

    2011-01-01

    Summary Background Neuronal elements underlying perception, cognition, and action exhibit distinct oscillatory phenomena, measured in humans by electro- or magnetoencephalography (EEG/MEG). So far, the correlative or causal nature of the link between brain oscillations and functions has remained elusive. A compelling demonstration of causality would primarily generate oscillatory signatures that are known to correlate with particular cognitive functions and then assess the behavioral consequences. Here, we provide the first direct evidence for causal entrainment of brain oscillations by transcranial magnetic stimulation (TMS) using concurrent EEG. Results We used rhythmic TMS bursts to directly interact with an MEG-identified parietal α-oscillator, activated by attention and linked to perception. With TMS bursts tuned to its preferred α-frequency (α-TMS), we confirmed the three main predictions of entrainment of a natural oscillator: (1) that α-oscillations are induced during α-TMS (reproducing an oscillatory signature of the stimulated parietal cortex), (2) that there is progressive enhancement of this α-activity (synchronizing the targeted, α-generator to the α-TMS train), and (3) that this depends on the pre-TMS phase of the background α-rhythm (entrainment of natural, ongoing α-oscillations). Control conditions testing different TMS burst profiles and TMS-EEG in a phantom head confirmed specificity of α-boosting to the case of synchronization between TMS train and neural oscillator. Conclusions The periodic electromagnetic force that is generated during rhythmic TMS can cause local entrainment of natural brain oscillations, emulating oscillatory signatures activated by cognitive tasks. This reveals a new mechanism of online TMS action on brain activity and can account for frequency-specific behavioral TMS effects at the level of biologically relevant rhythms. PMID:21723129

  2. Effect of Rhythmic Auditory Stimulation on Hemiplegic Gait Patterns

    PubMed Central

    Shin, Yoon-Kyum; Chong, Hyun Ju

    2015-01-01

    Purpose The purpose of our study was to investigate the effect of gait training with rhythmic auditory stimulation (RAS) on both kinematic and temporospatial gait patterns in patients with hemiplegia. Materials and Methods Eighteen hemiplegic patients diagnosed with either cerebral palsy or stroke participated in this study. All participants underwent the 4-week gait training with RAS. The treatment was performed for 30 minutes per each session, three sessions per week. RAS was provided with rhythmic beats using a chord progression on a keyboard. Kinematic and temporospatial data were collected and analyzed using a three-dimensional motion analysis system. Results Gait training with RAS significantly improved both proximal and distal joint kinematic patterns in hip adduction, knee flexion, and ankle plantar flexion, enhancing the gait deviation index (GDI) as well as ameliorating temporal asymmetry of the stance and swing phases in patients with hemiplegia. Stroke patients with previous walking experience demonstrated significant kinematic improvement in knee flexion in mid-swing and ankle dorsiflexion in terminal stance. Among stroke patients, subacute patients showed a significantly increased GDI score compared with chronic patients. In addition, household ambulators showed a significant effect on reducing anterior tilt of the pelvis with an enhanced GDI score, while community ambulators significantly increased knee flexion in mid-swing phase and ankle dorsiflexion in terminal stance phase. Conclusion Gait training with RAS has beneficial effects on both kinematic and temporospatial patterns in patients with hemiplegia, providing not only clinical implications of locomotor rehabilitation with goal-oriented external feedback using RAS but also differential effects according to ambulatory function. PMID:26446657

  3. Automatic tube current modulation for whole-body polytrauma CT with immobilization devices: is there an increase in radiation dose and degradation of image quality?

    PubMed

    Euler, André; Stieltjes, Bram; Schindera, Sebastian T

    2017-02-01

    The objective of this study was the assessment of the image quality and radiation dose in polytrauma CT using immobilization devices. An anthropomorphic whole body and a liver phantom were scanned on a 128-slice CT scanner with four different protocols using automatic tube current modulation (120 kVp, 150 ref. mAs; 120 kV, 200 ref. mAs; 140 kVp, 150 ref. mAs; and 140 kVp, 200 ref. mAs) and four different setups (no immobilization device (setup A), vacuum mattress 1 (setup B), vacuum mattress 2 (setup C), and spineboard (setup D)). Qualitative and quantitative image quality parameters and radiation dose were assessed. Image noise increased on average by 6.6, 11.2, and 9.4 %, and CNR decreased by 11.2, 13.9, and 6.5 for setups B, C, and D, respectively, compared with setup A. The CTDIvol increased up to 6 % using immobilization devices. Severe streak artifacts, provoked by the inflation valve of the mattresses were detected at the level of the head and shoulder. Applying immobilization devices for whole-body CT with automatic tube current modulation increases the radiation dose and decreases the quantitative image quality slightly. Severe artifacts, induced by the inflation valve of the mattress, can influence the diagnostic accuracy at the level of the head and shoulder.

  4. Perchlorate exposure does not modulate temporal variation of whole-body thyroid and androgen hormone content in threespine stickleback

    PubMed Central

    Gardell, Alison M.; Dillon, Danielle M.; Smayda, Lauren C.; von Hippel, Frank A.; Cresko, William A.; Postlethwait, John H.; Buck, C. Loren

    2015-01-01

    Previously we showed that exposure of threespine stickleback (Gasterosteus aculeatus) to the endocrine disruptor perchlorate results in pronounced structural changes in thyroid and gonad, while surprisingly, whole-body thyroid hormone concentrations remain unaffected. To test for hormone titer variations on a finer scale, we evaluated the interactive effects of time (diel and reproductive season) and perchlorate exposure on whole-body contents of triiodothyronine (T3), thyroxine (T4), and 11-ketotestosterone (11-KT) in captive stickleback. Adult stickleback were exposed to 100 ppm perchlorate or control water and sampled at four-hour intervals across the 24-hour day and at one time-point (1100 h) weekly across the reproductive season (May-July). Neither whole-body T3 nor T4 concentration significantly differed across the day in control or perchlorate treated stickleback. Across the reproductive season, whole-body T3 concentration remained stable while T4 significantly increased. However, neither hormone concentration was significantly affected by perchlorate, verifying our previous studies. The concentration of whole-body 11-KT, a major fish androgen, displayed significant diel variation and also steadily declined across the reproductive season in untreated males; perchlorate exposure did not influence the concentration of 11-KT in either diel or reproductive season schedules. Diel and reproductive season variations in 11-KT content in male stickleback are likely related to reproductive physiology and behavior. The observed increase in T4 content across the reproductive season may be reflective of increased energy investment in reproduction near the end of the life cycle. PMID:25733204

  5. Modulation of body composition and immune cell functions by conjugated linoleic acid in humans and animal models: benefits vs. risks.

    PubMed

    Kelley, D S; Erickson, K L

    2003-04-01

    We have reviewed the published literature regarding the effects of CLA on body composition and immune cell functions in humans and in animal models. Results from studies in mice, hamsters, rats, and pigs generally support the notion that CLA reduced depot fat in the normal or lean strains. However, in obese rats, it increased body fat or decreased it less than in the corresponding lean controls. These studies also indicate that t10,c12-CLA was the isomer that reduced adipose fat; however, it also increased the fat content of several other tissues and increased circulating insulin and the saturated FA content of adipose tissue and muscle. Four of the eight published human studies found small but significant reductions in body fat with CLA supplementation; however, the reductions were smaller than the prediction errors for the methods used. The other four human studies found no change in body fat with CLA supplementation. These studies also report that CLA supplementation increased the risk factors for diabetes and cardiovascular disease including increased blood glucose, insulin, insulin resistance, VLDL, C-reactive protein, lipid peroxidation, and decreased HDL. Most studies regarding the effects of CLA on immune cell functions have been conducted with a mixture of isomers, and the results have been variable. One study conducted in mice with the purified c9,t11-CLA and t10,c12-CLA isomers indicated that the two isomers have similar effects on immune cell functions. Some of the reasons for the discrepancies between the effects of CLA in published reports are discussed. Although significant benefit to humans from CLA supplementation is questionable, it may create several health risks in both humans and animals. On the basis of the published data, CLA supplementation of adult human diets to improve body composition or enhance immune functions cannot be recommended at this time.

  6. Brain Bases of Working Memory for Time Intervals in Rhythmic Sequences

    PubMed Central

    Teki, Sundeep; Griffiths, Timothy D.

    2016-01-01

    Perception of auditory time intervals is critical for accurate comprehension of natural sounds like speech and music. However, the neural substrates and mechanisms underlying the representation of time intervals in working memory are poorly understood. In this study, we investigate the brain bases of working memory for time intervals in rhythmic sequences using functional magnetic resonance imaging. We used a novel behavioral paradigm to investigate time-interval representation in working memory as a function of the temporal jitter and memory load of the sequences containing those time intervals. Human participants were presented with a sequence of intervals and required to reproduce the duration of a particular probed interval. We found that perceptual timing areas including the cerebellum and the striatum were more or less active as a function of increasing and decreasing jitter of the intervals held in working memory respectively whilst the activity of the inferior parietal cortex is modulated as a function of memory load. Additionally, we also analyzed structural correlations between gray and white matter density and behavior and found significant correlations in the cerebellum and the striatum, mirroring the functional results. Our data demonstrate neural substrates of working memory for time intervals and suggest that the cerebellum and the striatum represent core areas for representing temporal information in working memory. PMID:27313506

  7. Irregular and frequent cortisol secretory episodes with preserved diurnal rhythmicity in primary adrenal Cushing's syndrome.

    PubMed

    van Aken, M O; Pereira, A M; van Thiel, S W; van den Berg, G; Frölich, M; Veldhuis, J D; Romijn, J A; Roelfsema, F

    2005-03-01

    To evaluate the pathophysiology of altered cortisol secretion in patients with primary adrenal hypercortisolism, cortisol secretion was investigated in 12 patients, seven with a unilateral adenoma and five with ACTH-independent macronodular adrenal hyperplasia compared with age- and gender-matched controls and with patients with pituitary-dependent hypercortisolism. Pulsatile secretion was increased 2-fold (P = 0.04), attributable to increased event frequency (P = 0.002). All patients showed a significant diurnal rhythm with a delay in phase shift of 3 h (P = 0.01). Approximate entropy ratio, a feedback-sensitive measure, was increased compared with controls (P = 0.00003) but similar to that of pituitary-dependent hypercortisolism (P = 0.77), denoting loss of autoregulation. Cortisol burst-mass tended to be smaller in patients with ACTH-independent macronodular adrenal hyperplasia than in unilateral adenoma (P = 0.06). In conclusion, increased cortisol secretion in patients with primary adrenal Cushing's syndrome is caused by amplified pulsatile secretion via event frequency modulation. We speculate that partial preservation of secretory regularity and diurnal rhythmicity point to incomplete autonomy of these tumors.

  8. Different corticospinal control between discrete and rhythmic movement of the ankle

    PubMed Central

    Goto, Yumeno; Jono, Yasutomo; Hatanaka, Ryota; Nomura, Yoshifumi; Tani, Keisuke; Chujo, Yuta; Hiraoka, Koichi

    2014-01-01

    We investigated differences in corticospinal and spinal control between discrete and rhythmic ankle movements. Motor evoked potentials (MEPs) in the tibialis anterior and soleus muscles and soleus H-reflex were elicited in the middle of the plantar flexion phase during discrete ankle movement or in the initial or later cycles of rhythmic ankle movement. The H-reflex was evoked at an intensity eliciting a small M-wave and MEPs were elicited at an intensity of 1.2 times the motor threshold of the soleus MEPs. Only trials in which background EMG level, ankle angle, and ankle velocity were similar among the movement conditions were included for data analysis. In addition, only trials with a similar M-wave were included for data analysis in the experiment evoking H-reflexes. Results showed that H reflex and MEP amplitudes in the soleus muscle during discrete movement were not significantly different from those during rhythmic movement. MEP amplitude in the tibialis anterior muscle during the later cycles of rhythmic movement was significantly larger than that during the initial cycle of the rhythmic movement or during discrete movement. Higher corticospinal excitability in the tibialis anterior muscle during the later cycles of rhythmic movement may reflect changes in corticospinal control from the initial cycle to the later cycles of rhythmic movement. PMID:25126066

  9. Are non-human primates capable of rhythmic entrainment? Evidence for the gradual audiomotor evolution hypothesis.

    PubMed

    Merchant, Hugo; Honing, Henkjan

    2013-01-01

    We propose a decomposition of the neurocognitive mechanisms that might underlie interval-based timing and rhythmic entrainment. Next to reviewing the concepts central to the definition of rhythmic entrainment, we discuss recent studies that suggest rhythmic entrainment to be specific to humans and a selected group of bird species, but, surprisingly, is not obvious in non-human primates. On the basis of these studies we propose the gradual audiomotor evolution hypothesis that suggests that humans fully share interval-based timing with other primates, but only partially share the ability of rhythmic entrainment (or beat-based timing). This hypothesis accommodates the fact that non-human primates (i.e., macaques) performance is comparable to humans in single interval tasks (such as interval reproduction, categorization, and interception), but show differences in multiple interval tasks (such as rhythmic entrainment, synchronization, and continuation). Furthermore, it is in line with the observation that macaques can, apparently, synchronize in the visual domain, but show less sensitivity in the auditory domain. And finally, while macaques are sensitive to interval-based timing and rhythmic grouping, the absence of a strong coupling between the auditory and motor system of non-human primates might be the reason why macaques cannot rhythmically entrain in the way humans do.

  10. FrzCD, a methyl-accepting taxis protein from Myxococcus xanthus, shows modulated methylation during fruiting body formation.

    PubMed

    McBride, M J; Zusman, D R

    1993-08-01

    The frizzy (frz) genes of Myxococcus xanthus are required to control directed motility during vegetative growth and fruiting body formation. FrzCD, a protein homologous to the methyl-accepting chemotaxis proteins from enteric bacteria, is modified by methylation in response to environmental conditions. Transfer of cells from rich medium to fruiting medium initially caused rapid demethylation of FrzCD. Subsequently, the amount of FrzCD increased, but most remained unmethylated. At about the time of mound formation (9 h), most of the FrzCD was converted to methylated forms. Dispersal of developing cells (10 h) in buffer led to the demethylation of FrzCD, whereas concentration of these cells caused methylation of FrzCD. Some mutants which were unable to form fruiting bodies still modified their FrzCD during incubation under conditions of starvation on a surface.

  11. Effects of local and core body temperature on grip force modulation during movement-induced load force fluctuations.

    PubMed

    Cheung, Stephen S; Reynolds, Luke F; Macdonald, Mark A B; Tweedie, Constance L; Urquhart, Robin L; Westwood, David A

    2008-05-01

    Impaired manual functioning often occurs when the hands are exposed to cold temperatures, but the underlying mechanism is not clearly understood. Tactile feedback is thought to provide important information during object manipulations in order to scale and regulate grip forces; however, topical anaesthetic-induced tactile sensation impairments may not realistically simulate the systemic neuromuscular impairment of the whole hand that could occur during cold temperature exposure. In two experiments, we studied the impact of (1) local hand cooling [thermoneutral finger skin temperature, cold (<8 degrees C)] and (2) core body temperature (thermoneutral core body temperature, pre-heated by 0.5 degrees C, pre-cooled by 0.5 degrees C) with cold hands on manual dexterity and the ability to control and co-ordinate grip forces during a cyclical load-lifting task. In Experiment 1 (n = 10), hand cooling significantly decreased Purdue Pegboard performance (P = 0.002), while increasing grip force by approximately 5 N during the cyclical load-lifting task compared to thermoneutral (P = 0.037). The temporal co-ordination of grip and load forces was unaffected by hand cooling. In Experiment 2 (n = 11), pegboard performance was impaired following hand cooling (P < 0.001), and to a greater extent when the body was pre-cooled (p < 0.001). However, neither grip force (P = 0.99) nor the temporal co-ordination of grasping and lifting forces (P = 0.85) were affected by core body temperature. These data support the existence of a robust centrally controlled feedforward system able to anticipate the dynamics of manual manipulations and accordingly regulate the temporal co-ordination of fingertip forces during object manipulation. This centrally controlled mechanism appears to differ from the mechanisms governing other aspects of manual dexterity.

  12. Prenatal exposure of a novel antipsychotic aripiprazole: impact on maternal, fetal and postnatal body weight modulation in rats.

    PubMed

    Singh, K P; Tripathi, Nidhi

    2014-03-01

    Nearly all atypical antipsychotic drugs (AAPDs) of second- generation are associated with body weight gain in adults with prolonged exposure; but reports on third-generation AAPDs like Aripiprazole (ARI) and weight gain are scanty and ambiguous. This may be attributed to some unknown mechanism of action, the study of which is essential to investigate gestational exposure of equivalent therapeutic doses of ARI on maternal and fetal weight gain and its longlasting impact on postnatal development and growth of offspring in rodent model. 30 pregnant Wistar rats were exposed to selected doses (2mg, 3mg and 5mg/kg BW) of ARI from GD3-21 orally, with control subjects. Half of the pregnant subjects of each group were sacrificed at GD22 and rest dams were allowed to deliver normally and pups were reared postnatally up to 10 weeks of age. In ARI treated groups, there was no substantial alteration of body weight gain and food intake in pregnant subjects while significant reduction was found in fetal and postnatal (pre-and post weaning) body weight gain. ARI was found neutral for substantial weight gain in pregnant rats but may induce significant weight loss in fetuses, creating long-lasting negative impact on offspring growth (in weight) till PND70. Therefore, ARI could be a good alternative of second- generation AAPDs for adult females but may not be safe for developing fetuses and offspring.

  13. Meal time shift disturbs circadian rhythmicity along with metabolic and behavioral alterations in mice.

    PubMed

    Yoon, Ji-Ae; Han, Dong-Hee; Noh, Jong-Yun; Kim, Mi-Hee; Son, Gi Hoon; Kim, Kyungjin; Kim, Chang-Ju; Pak, Youngmi Kim; Cho, Sehyung

    2012-01-01

    In modern society, growing numbers of people are engaged in various forms of shift works or trans-meridian travels. Such circadian misalignment is known to disturb endogenous diurnal rhythms, which may lead to harmful physiological consequences including metabolic syndrome, obesity, cancer, cardiovascular disorders, and gastric disorders as well as other physical and mental disorders. However, the precise mechanism(s) underlying these changes are yet unclear. The present work, therefore examined the effects of 6 h advance or delay of usual meal time on diurnal rhythmicities in home cage activity (HCA), body temperature (BT), blood metabolic markers, glucose homeostasis, and expression of genes that are involved in cholesterol homeostasis by feeding young adult male mice in a time-restrictive manner. Delay of meal time caused locomotive hyperactivity in a significant portion (42%) of subjects, while 6 h advance caused a torpor-like symptom during the late scotophase. Accordingly, daily rhythms of blood glucose and triglyceride were differentially affected by time-restrictive feeding regimen with concurrent metabolic alterations. Along with these physiological changes, time-restrictive feeding also influenced the circadian expression patterns of low density lipoprotein receptor (LDLR) as well as most LDLR regulatory factors. Strikingly, chronic advance of meal time induced insulin resistance, while chronic delay significantly elevated blood glucose levels. Taken together, our findings indicate that persistent shifts in usual meal time impact the diurnal rhythms of carbohydrate and lipid metabolisms in addition to HCA and BT, thereby posing critical implications for the health and diseases of shift workers.

  14. NMDA and PACAP Receptor Signaling Interact to Mediate Retinal-Induced SCN Cellular Rhythmicity in the Absence of Light

    PubMed Central

    Webb, Ian C.; Coolen, Lique M.; Lehman, Michael N.

    2013-01-01

    The “core” region of the suprachiasmatic nucleus (SCN), a central clock responsible for coordinating circadian rhythms, shows a daily rhythm in phosphorylation of extracellular regulated kinase (pERK). This cellular rhythm persists under constant darkness and, despite the absence of light, is dependent upon inputs from the eye. The neural signals driving this rhythmicity remain unknown and here the roles of glutamate and PACAP are examined. First, rhythmic phosphorylation of the NR1 NMDA receptor subunit (pNR1, a marker for receptor activation) was shown to coincide with SCN core pERK, with a peak at circadian time (CT) 16. Enucleation and intraocular TTX administration attenuated the peak in the pERK and pNR1 rhythms, demonstrating that activation of the NMDA receptor and ERK in the SCN core at CT16 are dependent on retinal inputs. In contrast, ERK and NR1 phosphorylation in the SCN shell region were unaffected by these treatments. Intraventricular administration of the NMDA receptor antagonist MK-801 also attenuated the peak in SCN core pERK, indicating that ERK phosphorylation in this region requires NMDA receptor activation. As PACAP is implicated in photic entrainment and is known to modulate glutamate signaling, the effects of a PAC1 receptor antagonist (PACAP 6-38) on SCN core pERK and pNR1 also were examined. PACAP 6-38 administration attenuated SCN core pERK and pNR1, suggesting that PACAP induces pERK directly, and indirectly via a modulation of NMDA receptor signaling. Together, these data indicate that, in the absence of light, retinal-mediated NMDA and PAC1 receptor activation interact to induce cellular rhythms in the SCN core. These results highlight a novel function for glutamate and PACAP release in the hamster SCN apart from their well-known roles in the induction of photic circadian clock resetting. PMID:24098484

  15. Coilin, the signature protein of Cajal bodies, differentially modulates the interactions of plants with viruses in widely different taxa.

    PubMed

    Shaw, Jane; Love, Andrew J; Makarova, Svetlana S; Kalinina, Natalia O; Harrison, Bryan D; Taliansky, Michael E

    2014-01-01

    Cajal bodies (CBs) are distinct nuclear bodies physically and functionally associated with the nucleolus. In addition to their traditional function in coordinating maturation of certain nuclear RNAs, CBs participate in cell cycle regulation, development, and regulation of stress responses. A key "signature" component of CBs is coilin, the scaffolding protein essential for CB formation and function. Using an RNA silencing (loss-of-function) approach, we describe here new phenomena whereby coilin also affects, directly or indirectly, a variety of interactions between host plants and viruses that have RNA or DNA genomes. Moreover, the effects of coilin on these interactions are manifested differently: coilin contributes to plant defense against tobacco rattle virus (tobravirus), tomato black ring virus (nepovirus), barley stripe mosaic virus (hordeivirus), and tomato golden mosaic virus (begomovirus). In contrast, with potato virus Y (potyvirus) and turnip vein clearing virus (tobamovirus), coilin serves to increase virus pathogenicity. These findings show that interactions with coilin (or CBs) may involve diverse mechanisms with different viruses and that these mechanisms act at different phases of virus infection. Thus, coilin (CBs) has novel, unexpected natural functions that may be recruited or subverted by plant viruses for their own needs or, in contrast, are involved in plant defense mechanisms that suppress host susceptibility to the viruses.

  16. Corticomuscular coherence is tuned to the spontaneous rhythmicity of speech at 2-3 Hz.

    PubMed

    Ruspantini, Irene; Saarinen, Timo; Belardinelli, Paolo; Jalava, Antti; Parviainen, Tiina; Kujala, Jan; Salmelin, Riitta

    2012-03-14

    Human speech features rhythmicity that frames distinctive, fine-grained speech patterns. Speech can thus be counted among rhythmic motor behaviors that generally manifest characteristic spontaneous rates. However, the critical neural evidence for tuning of articulatory control to a spontaneous rate of speech has not been uncovered. The present study examined the spontaneous rhythmicity in speech production and its relationship to cortex-muscle neurocommunication, which is essential for speech control. Our MEG results show that, during articulation, coherent oscillatory coupling between the mouth sensorimotor cortex and the mouth muscles is strongest at the frequency of spontaneous rhythmicity of speech at 2-3 Hz, which is also the typical rate of word production. Corticomuscular coherence, a measure of efficient cortex-muscle neurocommunication, thus reveals behaviorally relevant oscillatory tuning for spoken language.

  17. The Performance of Bach: Study of Rhythmic Timing by Skilled Musicians.

    ERIC Educational Resources Information Center

    Johnson, Christopher M.

    1999-01-01

    Analyzes 15 performances of "Bach's Suite Number 3 for Violoncello solo, Bourree Number 1" and determines what patterns of rhythmic variation (rubato) were used by soloists. Indicates that the soloists demonstrated four identifiable and similar trends in the performances. (CMK)

  18. Influence of Tempo and Rhythmic Unit in Musical Emotion Regulation

    PubMed Central

    Fernández-Sotos, Alicia; Fernández-Caballero, Antonio; Latorre, José M.

    2016-01-01

    This article is based on the assumption of musical power to change the listener's mood. The paper studies the outcome of two experiments on the regulation of emotional states in a series of participants who listen to different auditions. The present research focuses on note value, an important musical cue related to rhythm. The influence of two concepts linked to note value is analyzed separately and discussed together. The two musical cues under investigation are tempo and rhythmic unit. The participants are asked to label music fragments by using opposite meaningful words belonging to four semantic scales, namely “Tension” (ranging from Relaxing to Stressing), “Expressiveness” (Expressionless to Expressive), “Amusement” (Boring to Amusing) and “Attractiveness” (Pleasant to Unpleasant). The participants also have to indicate how much they feel certain basic emotions while listening to each music excerpt. The rated emotions are “Happiness,” “Surprise,” and “Sadness.” This study makes it possible to draw some interesting conclusions about the associations between note value and emotions. PMID:27536232

  19. Photosynthetic circadian rhythmicity patterns of Symbiodium, the coral endosymbiotic algae

    PubMed Central

    Sorek, Michal; Yacobi, Yosef Z.; Roopin, Modi; Berman-Frank, Ilana; Levy, Oren

    2013-01-01

    Biological clocks are self-sustained endogenous timers that enable organisms (from cyanobacteria to humans) to anticipate daily environmental rhythms, and adjust their physiology and behaviour accordingly. Symbiotic corals play a central role in the creation of biologically rich ecosystems based on mutualistic symbioses between the invertebrate coral and dinoflagellate protists from the genus Symbiodinium. In this study, we experimentally establish that Symbiodinium photosynthesis, both as a free-living unicellular algae and as part of the symbiotic association with the coral Stylophora pistillata, is ‘wired’ to the circadian clock mechanism with a ‘free-run’ cycle close to 24 h. Associated photosynthetic pigments also showed rhythmicity under light/dark conditions and under constant light conditions, while the expression of the oxygen-evolving enhancer 1 gene (within photosystem II) coincided with photosynthetically evolved oxygen in Symbiodinium cultures. Thus, circadian regulation of the Symbiodinium photosynthesis is, however, complicated as being linked to the coral/host that have probably profound physiochemical influence on the intracellular environment. The temporal patterns of photosynthesis demonstrated here highlight the physiological complexity and interdependence of the algae circadian clock associated in this symbiosis and the plasticity of algae regulatory mechanisms downstream of the circadian clock. PMID:23554392

  20. Familiarity with music increases walking speed in rhythmic auditory cuing.

    PubMed

    Leow, Li-Ann; Rinchon, Cricia; Grahn, Jessica

    2015-03-01

    Rhythmic auditory stimulation (RAS) is a gait rehabilitation method in which patients synchronize footsteps to a metronome or musical beats. Although RAS with music can ameliorate gait abnormalities, outcomes vary, possibly because music properties, such as groove or familiarity, differ across interventions. To optimize future interventions, we assessed how initially familiar and unfamiliar low-groove and high-groove music affected synchronization accuracy and gait in healthy individuals. We also experimentally increased music familiarity using repeated exposure to initially unfamiliar songs. Overall, familiar music elicited faster stride velocity and less variable strides, as well as better synchronization performance (matching of step tempo to beat tempo). High-groove music, as reported previously, led to faster stride velocity than low-groove music. We propose two mechanisms for familiarity's effects. First, familiarity with the beat structure reduces cognitive demands of synchronizing, leading to better synchronization performance and faster, less variable gait. Second, familiarity might have elicited faster gait by increasing enjoyment of the music, as enjoyment was higher after repeated exposure to initially low-enjoyment songs. Future studies are necessary to dissociate the contribution of these mechanisms to the observed RAS effects of familiar music on gait.

  1. Effect of temporal separation on synchronization in rhythmic performance.

    PubMed

    Chafe, Chris; Cáceres, Juan-Pablo; Gurevich, Michael

    2010-01-01

    A variety of short time delays inserted between pairs of subjects were found to affect their ability to synchronize a musical task. The subjects performed a clapping rhythm together from separate sound-isolated rooms via headphones and without visual contact. One-way time delays between pairs were manipulated electronically in the range of 3 to 78 ms. We are interested in quantifying the envelope of time delay within which two individuals produce synchronous performances. The results indicate that there are distinct regimes of mutually coupled behavior, and that 'natural time delay'--delay within the narrow range associated with travel times across spatial arrangements of groups and ensembles--supports the most stable performance. Conditions outside of this envelope, with time delays both below and above it, create characteristic interaction dynamics in the mutually coupled actions of the duo. Trials at extremely short delays (corresponding to unnaturally close proximity) had a tendency to accelerate from anticipation. Synchronization lagged at longer delays (larger than usual physical distances) and produced an increasingly severe deceleration and then deterioration of performed rhythms. The study has implications for music collaboration over the Internet and suggests that stable rhythmic performance can be achieved by 'wired ensembles' across distances of thousands of kilometers.

  2. Evening physical activity alters wrist temperature circadian rhythmicity.

    PubMed

    Rubio-Sastre, Patricia; Gómez-Abellán, Purificación; Martinez-Nicolas, Antonio; Ordovás, José María; Madrid, Juan Antonio; Garaulet, Marta

    2014-03-01

    The adequate time to perform physical activity (PA) to maintain optimal circadian system health has not been defined. We studied the influence of morning and evening PA on circadian rhythmicity in 16 women with wrist temperature (WT). Participants performed controlled PA (45 min continuous-running) during 7 days in the morning (MPA) and evening (EPA) and results were compared with a no-exercise-week (C). EPA was characterized by a lower amplitude (evening: 0.028 ± 0.01 °C versus control: 0.038 ± 0.016 °C; p < 0.05) less pronounced second-harmonic (power) (evening: 0.41 ± 0.47 versus morning: 1.04 ± 0.59); and achrophase delay (evening: 06:35 ± 02:14 h versus morning: 04:51 ± 01:11 h; p < 0.05) as compared to MPA and C. Performing PA in the late evening might not be as beneficial as in the morning.

  3. Rhythmic oscillations of visual contrast sensitivity synchronized with action.

    PubMed

    Tomassini, Alice; Spinelli, Donatella; Jacono, Marco; Sandini, Giulio; Morrone, Maria Concetta

    2015-05-06

    It is well known that the motor and the sensory systems structure sensory data collection and cooperate to achieve an efficient integration and exchange of information. Increasing evidence suggests that both motor and sensory functions are regulated by rhythmic processes reflecting alternating states of neuronal excitability, and these may be involved in mediating sensory-motor interactions. Here we show an oscillatory fluctuation in early visual processing time locked with the execution of voluntary action, and, crucially, even for visual stimuli irrelevant to the motor task. Human participants were asked to perform a reaching movement toward a display and judge the orientation of a Gabor patch, near contrast threshold, briefly presented at random times before and during the reaching movement. When the data are temporally aligned to the onset of movement, visual contrast sensitivity oscillates with periodicity within the theta band. Importantly, the oscillations emerge during the motor planning stage, ∼500 ms before movement onset. We suggest that brain oscillatory dynamics may mediate an automatic coupling between early motor planning and early visual processing, possibly instrumental in linking and closing up the visual-motor control loop.

  4. Modulation of the release of ( sup 3 H)norepinephrine from the base and body of the rat urinary bladder by endogenous adrenergic and cholinergic mechanisms

    SciTech Connect

    Somogyi, G.T.; de Groat, W.C. )

    1990-10-01

    Modulation of (3H)NE release was studied in rat urinary bladder strips prelabeled with (3H)NE. (3H)NE uptake occurred in strips from the bladder base and body, but was very prominent in the base where the noradrenergic innervation is most dense. Electrical field stimulation markedly increased (3H)NE outflow from the superfused tissue. The quantity of (3H)NE release was approximately equal during three consecutive periods of stimulation. Activation of presynaptic muscarinic receptors by 1.0 microM oxotremorine reduced (3H)NE release to 46% of the control. Atropine (1 microM) blocked the effect of oxotremorine and increased the release to 147% of predrug control levels. Activation of presynaptic alpha-2 adrenoceptors by 1 microM clonidine reduced (3H)NE release to 55% of control. Yohimbine blocked the action of clonidine and increased the release to 148% of control. The release of (3H)NE from the bladder base and body was increased by both 1 microM atropine (to 167% and 174% of control, respectively) and 1 microM yohimbine (to 286% and 425% of control, respectively). Atropine and yohimbine administered in combination had similar facilitatory effects as when administered alone. We conclude that the release of (3H)NE from adrenergic nerve endings in electrically stimulated bladder strips is modulated via endogenous transmitters acting on both muscarinic and alpha-2 adrenergic presynaptic receptors and that the latter provide the most prominent control.

  5. Inflammasome components ASC and AIM2 modulate the acute phase of biomaterial implant-induced foreign body responses

    PubMed Central

    Christo, Susan N.; Diener, Kerrilyn R.; Manavis, Jim; Grimbaldeston, Michele A.; Bachhuka, Akash; Vasilev, Krasimir; Hayball, John D.

    2016-01-01

    Detailing the inflammatory mechanisms of biomaterial-implant induced foreign body responses (FBR) has implications for revealing targetable pathways that may reduce leukocyte activation and fibrotic encapsulation of the implant. We have adapted a model of poly(methylmethacrylate) (PMMA) bead injection to perform an assessment of the mechanistic role of the ASC-dependent inflammasome in this process. We first demonstrate that ASC−/− mice subjected to PMMA bead injections had reduced cell infiltration and altered collagen deposition, suggesting a role for the inflammasome in the FBR. We next investigated the NLRP3 and AIM2 sensors because of their known contributions in recognising damaged and apoptotic cells. We found that NLRP3 was dispensable for the fibrotic encapsulation; however AIM2 expression influenced leukocyte infiltration and controlled collagen deposition, suggesting a previously unexplored link between AIM2 and biomaterial-induced FBR. PMID:26860464

  6. Inflammasome components ASC and AIM2 modulate the acute phase of biomaterial implant-induced foreign body responses.

    PubMed

    Christo, Susan N; Diener, Kerrilyn R; Manavis, Jim; Grimbaldeston, Michele A; Bachhuka, Akash; Vasilev, Krasimir; Hayball, John D

    2016-02-10

    Detailing the inflammatory mechanisms of biomaterial-implant induced foreign body responses (FBR) has implications for revealing targetable pathways that may reduce leukocyte activation and fibrotic encapsulation of the implant. We have adapted a model of poly(methylmethacrylate) (PMMA) bead injection to perform an assessment of the mechanistic role of the ASC-dependent inflammasome in this process. We first demonstrate that ASC(-/-) mice subjected to PMMA bead injections had reduced cell infiltration and altered collagen deposition, suggesting a role for the inflammasome in the FBR. We next investigated the NLRP3 and AIM2 sensors because of their known contributions in recognising damaged and apoptotic cells. We found that NLRP3 was dispensable for the fibrotic encapsulation; however AIM2 expression influenced leukocyte infiltration and controlled collagen deposition, suggesting a previously unexplored link between AIM2 and biomaterial-induced FBR.

  7. Jazz drummers recruit language-specific areas for the processing of rhythmic structure.

    PubMed

    Herdener, Marcus; Humbel, Thierry; Esposito, Fabrizio; Habermeyer, Benedikt; Cattapan-Ludewig, Katja; Seifritz, Erich

    2014-03-01

    Rhythm is a central characteristic of music and speech, the most important domains of human communication using acoustic signals. Here, we investigated how rhythmical patterns in music are processed in the human brain, and, in addition, evaluated the impact of musical training on rhythm processing. Using fMRI, we found that deviations from a rule-based regular rhythmic structure activated the left planum temporale together with Broca's area and its right-hemispheric homolog across subjects, that is, a network also crucially involved in the processing of harmonic structure in music and the syntactic analysis of language. Comparing the BOLD responses to rhythmic variations between professional jazz drummers and musical laypersons, we found that only highly trained rhythmic experts show additional activity in left-hemispheric supramarginal gyrus, a higher-order region involved in processing of linguistic syntax. This suggests an additional functional recruitment of brain areas usually dedicated to complex linguistic syntax processing for the analysis of rhythmical patterns only in professional jazz drummers, who are especially trained to use rhythmical cues for communication.

  8. Circadian and feeding rhythms differentially affect rhythmic mRNA transcription and translation in mouse liver

    PubMed Central

    Atger, Florian; Gobet, Cédric; Marquis, Julien; Martin, Eva; Wang, Jingkui; Weger, Benjamin; Lefebvre, Grégory; Descombes, Patrick; Naef, Felix; Gachon, Frédéric

    2015-01-01

    Diurnal oscillations of gene expression are a hallmark of rhythmic physiology across most living organisms. Such oscillations are controlled by the interplay between the circadian clock and feeding rhythms. Although rhythmic mRNA accumulation has been extensively studied, comparatively less is known about their transcription and translation. Here, we quantified simultaneously temporal transcription, accumulation, and translation of mouse liver mRNAs under physiological light–dark conditions and ad libitum or night-restricted feeding in WT and brain and muscle Arnt-like 1 (Bmal1)-deficient animals. We found that rhythmic transcription predominantly drives rhythmic mRNA accumulation and translation for a majority of genes. Comparison of wild-type and Bmal1 KO mice shows that circadian clock and feeding rhythms have broad impact on rhythmic gene expression, Bmal1 deletion affecting surprisingly both transcriptional and posttranscriptional levels. Translation efficiency is differentially regulated during the diurnal cycle for genes with 5′-Terminal Oligo Pyrimidine tract (5′-TOP) sequences and for genes involved in mitochondrial activity, many harboring a Translation Initiator of Short 5′-UTR (TISU) motif. The increased translation efficiency of 5′-TOP and TISU genes is mainly driven by feeding rhythms but Bmal1 deletion also affects amplitude and phase of translation, including TISU genes. Together this study emphasizes the complex interconnections between circadian and feeding rhythms at several steps ultimately determining rhythmic gene expression and translation. PMID:26554015

  9. Sympathetic network drive during water deprivation does not increase respiratory or cardiac rhythmic sympathetic nerve activity.

    PubMed

    Holbein, Walter W; Toney, Glenn M

    2013-06-15

    Effects of water deprivation on rhythmic bursting of sympathetic nerve activity (SNA) were investigated in anesthetized, bilaterally vagotomized, euhydrated (control) and 48-h water-deprived (WD) rats (n = 8/group). Control and WD rats had similar baseline values of mean arterial pressure, heart rate, end-tidal CO2, and central respiratory drive. Although integrated splanchnic SNA (sSNA) was greater in WD rats than controls (P < 0.01), analysis of respiratory rhythmic bursting of sSNA revealed that inspiratory rhythmic burst amplitude was actually smaller (P < 0.005) in WD rats (+68 ± 6%) than controls (+208 ± 20%), and amplitudes of the early expiratory (postinspiratory) trough and late expiratory burst of sSNA were not different between groups. Further analysis revealed that water deprivation had no effect on either the amplitude or periodicity of the cardiac rhythmic oscillation of sSNA. Collectively, these data indicate that the increase of sSNA produced by water deprivation is not attributable to either increased respiratory or cardiac rhythmic burst discharge. Thus the sympathetic network response to acute water deprivation appears to differ from that of chronic sympathoexcitation in neurogenic forms of arterial hypertension, where increased respiratory rhythmic bursting of SNA and baroreflex adaptations have been reported.

  10. Circadian and feeding rhythms differentially affect rhythmic mRNA transcription and translation in mouse liver.

    PubMed

    Atger, Florian; Gobet, Cédric; Marquis, Julien; Martin, Eva; Wang, Jingkui; Weger, Benjamin; Lefebvre, Grégory; Descombes, Patrick; Naef, Felix; Gachon, Frédéric

    2015-11-24

    Diurnal oscillations of gene expression are a hallmark of rhythmic physiology across most living organisms. Such oscillations are controlled by the interplay between the circadian clock and feeding rhythms. Although rhythmic mRNA accumulation has been extensively studied, comparatively less is known about their transcription and translation. Here, we quantified simultaneously temporal transcription, accumulation, and translation of mouse liver mRNAs under physiological light-dark conditions and ad libitum or night-restricted feeding in WT and brain and muscle Arnt-like 1 (Bmal1)-deficient animals. We found that rhythmic transcription predominantly drives rhythmic mRNA accumulation and translation for a majority of genes. Comparison of wild-type and Bmal1 KO mice shows that circadian clock and feeding rhythms have broad impact on rhythmic gene expression, Bmal1 deletion affecting surprisingly both transcriptional and posttranscriptional levels. Translation efficiency is differentially regulated during the diurnal cycle for genes with 5'-Terminal Oligo Pyrimidine tract (5'-TOP) sequences and for genes involved in mitochondrial activity, many harboring a Translation Initiator of Short 5'-UTR (TISU) motif. The increased translation efficiency of 5'-TOP and TISU genes is mainly driven by feeding rhythms but Bmal1 deletion also affects amplitude and phase of translation, including TISU genes. Together this study emphasizes the complex interconnections between circadian and feeding rhythms at several steps ultimately determining rhythmic gene expression and translation.

  11. A Computational Model for Rhythmic and Discrete Movements in Uni- and Bimanual Coordination

    PubMed Central

    Ronsse, Renaud; Sternad, Dagmar; Lefèvre, Philippe

    2012-01-01

    Current research on discrete and rhythmic movements differs in both experimental procedures and theory, despite the ubiquitous overlap between discrete and rhythmic components in everyday behaviors. Models of rhythmic movements usually use oscillatory systems mimicking central pattern generators (CPGs). In contrast, models of discrete movements often employ optimization principles, thereby reflecting the higher-level cortical resources involved in the generation of such movements. This letter proposes a unified model for the generation of both rhythmic and discrete movements. We show that a physiologically motivated model of a CPG can not only generate simple rhythmic movements with only a small set of parameters, but can also produce discrete movements if the CPG is fed with an exponentially decaying phasic input. We further show that a particular coupling between two of these units can reproduce main findings on in-phase and antiphase stability. Finally, we propose an integrated model of combined rhythmic and discrete movements for the two hands. These movement classes are sequentially addressed in this letter with increasing model complexity. The model variations are discussed in relation to the degree of recruitment of the higher-level cortical resources, necessary for such movements. PMID:19018700

  12. Rhythmic cognition in humans and animals: distinguishing meter and pulse perception

    PubMed Central

    Fitch, W. Tecumseh

    2013-01-01

    This paper outlines a cognitive and comparative perspective on human rhythmic cognition that emphasizes a key distinction between pulse perception and meter perception. Pulse perception involves the extraction of a regular pulse or “tactus” from a stream of events. Meter perception involves grouping of events into hierarchical trees with differing levels of “strength”, or perceptual prominence. I argue that metrically-structured rhythms are required to either perform or move appropriately to music (e.g., to dance). Rhythms, from this metrical perspective, constitute “trees in time.” Rhythmic syntax represents a neglected form of musical syntax, and warrants more thorough neuroscientific investigation. The recent literature on animal entrainment clearly demonstrates the capacity to extract the pulse from rhythmic music, and to entrain periodic movements to this pulse, in several parrot species and a California sea lion, and a more limited ability to do so in one chimpanzee. However, the ability of these or other species to infer hierarchical rhythmic trees remains, for the most part, unexplored (with some apparent negative results from macaques). The results from this animal comparative research, combined with new methods to explore rhythmic cognition neurally, provide exciting new routes for understanding not just rhythmic cognition, but hierarchical cognition more generally, from a biological and neural perspective. PMID:24198765

  13. Towards an in vitro model mimicking the foreign body response: tailoring the surface properties of biomaterials to modulate extracellular matrix

    PubMed Central

    Damanik, Febriyani F. R.; Rothuizen, Tonia C.; van Blitterswijk, Clemens; Rotmans, Joris I.; Moroni, Lorenzo

    2014-01-01

    Despite various studies to minimize host reaction following a biomaterial implantation, an appealing strategy in regenerative medicine is to actively use such an immune response to trigger and control tissue regeneration. We have developed an in vitro model to modulate the host response by tuning biomaterials' surface properties through surface modifications techniques as a new strategy for tissue regeneration applications. Results showed tunable surface topography, roughness, wettability, and chemistry by varying treatment type and exposure, allowing for the first time to correlate the effect of these surface properties on cell attachment, morphology, strength and proliferation, as well as proinflammatory (IL-1β, IL-6) and antiflammatory cytokines (TGF-β1, IL-10) secreted in medium, and protein expression of collagen and elastin. Surface microstructuring, derived from chloroform partial etching, increased surface roughness and oxygen content. This resulted in enhanced cell adhesion, strength and proliferation as well as a balance of soluble factors for optimum collagen and elastin synthesis for tissue regeneration. By linking surface parameters to cell activity, we could determine the fate of the regenerated tissue to create successful soft tissue-engineered replacement. PMID:25234587

  14. Towards an in vitro model mimicking the foreign body response: tailoring the surface properties of biomaterials to modulate extracellular matrix

    NASA Astrophysics Data System (ADS)

    Damanik, Febriyani F. R.; Rothuizen, Tonia C.; van Blitterswijk, Clemens; Rotmans, Joris I.; Moroni, Lorenzo

    2014-09-01

    Despite various studies to minimize host reaction following a biomaterial implantation, an appealing strategy in regenerative medicine is to actively use such an immune response to trigger and control tissue regeneration. We have developed an in vitro model to modulate the host response by tuning biomaterials' surface properties through surface modifications techniques as a new strategy for tissue regeneration applications. Results showed tunable surface topography, roughness, wettability, and chemistry by varying treatment type and exposure, allowing for the first time to correlate the effect of these surface properties on cell attachment, morphology, strength and proliferation, as well as proinflammatory (IL-1β, IL-6) and antiflammatory cytokines (TGF-β1, IL-10) secreted in medium, and protein expression of collagen and elastin. Surface microstructuring, derived from chloroform partial etching, increased surface roughness and oxygen content. This resulted in enhanced cell adhesion, strength and proliferation as well as a balance of soluble factors for optimum collagen and elastin synthesis for tissue regeneration. By linking surface parameters to cell activity, we could determine the fate of the regenerated tissue to create successful soft tissue-engineered replacement.

  15. Modulation of the Foreign Body Reaction for Implants in the Subcutaneous Space: Microdialysis Probes as Localized Drug Delivery/Sampling Devices

    PubMed Central

    Mou, Xiaodun; Lennartz, Michelle R; Loegering, Daniel J; Stenken, Julie A

    2011-01-01

    Modulation of the foreign body reaction is considered to be an important step toward creation of implanted sensors with reliable long-term performance. In this work, microdialysis probes were implanted into the subcutaneous space of Sprague-Dawley rats. The probe performance was evaluated by comparing collected endogenous glucose concentrations with internal standard calibration (2-deoxyglucose, antipyrine, and vitamin B12). Probes were tested until failure, which for this work was defined as loss of fluid flow. In order to determine the effect of fibrous capsule formation on probe function, monocyte chemoattractant protein-1/CC chemokine ligand 2 (MCP-1/CCL2) was delivered locally via the probe to increase capsule thickness and dexamethasone 21-phosphate was delivered to reduce capsule thickness. Probes delivering MCP-1 had a capsule that was twice the thickness (500–600 μm) of control probes (200–225 μm) and typically failed 2 days earlier than control probes. Probes delivering dexamethasone 21-phosphate had more fragile capsules and the probes typically failed 2 days later than controls. Unexpectedly, extraction efficiency and collected glucose concentrations exhibited minor differences between groups. This is an interesting result in that the foreign body capsule formation was related to the duration of probe function but did not consistently relate to probe calibration. PMID:21722577

  16. Effects of modulators of AMP-activated protein kinase on TASK-1/3 and intracellular Ca2+ concentration in rat carotid body glomus cells

    PubMed Central

    Kim, Donghee; Kang1,2, Dawon; Martin, Elizabeth A.; Kim, Insook; Carroll, John L.

    2014-01-01

    Acute hypoxia depolarizes carotid body chemoreceptor (glomus) cells and elevates intracellular Ca2+ concentration ([Ca2+]i). Recent studies suggest that AMP-activated protein kinase (AMPK) mediates these effects of hypoxia by inhibiting the background K+ channels such as TASK. Here we studied the effects of modulators of AMPK on TASK activity in cell-attached patches. Activators of AMPK (1 mM AICAR and 0.1–0.5 mM A769662) did not inhibit TASK activity or cause depolarization during acute (10 min) or prolonged (2–3 hr) exposure. Hypoxia inhibited TASK activity by ~70% in cells pretreated with AICAR or A769662. Both AICAR and A769662 (15–40 min) failed to increase [Ca2+]i in glomus cells. Compound C (40 µM), an inhibitor of AMPK, showed no effect on hypoxia-induced inhibition of TASK. AICAR and A769662 phosphorylated AMPKα in PC12 cells, and Compound C blocked the phosphorylation. Our results suggest that AMPK does not affect TASK activity and is not involved in hypoxia-induced elevation of intracellular [Ca2+] in isolated rat carotid body glomus cells. PMID:24530802

  17. Interactions between dietary oil treatments and genetic variants modulate fatty acid ethanolamides in plasma and body weight composition.

    PubMed

    Pu, Shuaihua; Eck, Peter; Jenkins, David J A; Connelly, Philip W; Lamarche, Benoît; Kris-Etherton, Penny M; West, Sheila G; Liu, Xiaoran; Jones, Peter J H

    2016-03-28

    Fatty acid ethanolamides (FAE), a group of lipid mediators derived from long-chain fatty acids (FA), mediate biological activities including activation of cannabinoid receptors, stimulation of fat oxidation and regulation of satiety. However, how circulating FAE levels are influenced by FA intake in humans remains unclear. The objective of the present study was to investigate the response of six major circulating FAE to various dietary oil treatments in a five-period, cross-over, randomised, double-blind, clinical study in volunteers with abdominal obesity. The treatment oils (60 g/12 552 kJ per d (60 g/3000 kcal per d)) provided for 30 d were as follows: conventional canola oil, high oleic canola oil, high oleic canola oil enriched with DHA, flax/safflower oil blend and corn/safflower oil blend. Two SNP associated with FAE degradation and synthesis were studied. Post-treatment results showed overall that plasma FAE levels were modulated by dietary FA and were positively correlated with corresponding plasma FA levels; minor allele (A) carriers of SNP rs324420 in gene fatty acid amide hydrolase produced higher circulating oleoylethanolamide (OEA) (P=0·0209) and docosahexaenoylethanolamide (DHEA) levels (P=0·0002). In addition, elevated plasma DHEA levels in response to DHA intake tended to be associated with lower plasma OEA levels and an increased gynoid fat mass. In summary, data suggest that the metabolic and physiological responses to dietary FA may be influenced via circulating FAE. Genetic analysis of rs324420 might help identify a sub-population that appears to benefit from increased consumption of DHA and oleic acid.

  18. Weibel-Palade body size modulates the adhesive activity of its von Willebrand Factor cargo in cultured endothelial cells

    PubMed Central

    Ferraro, Francesco; Mafalda Lopes da, Silva; Grimes, William; Lee, Hwee Kuan; Ketteler, Robin; Kriston-Vizi, Janos; Cutler, Daniel F.

    2016-01-01

    Changes in the size of cellular organelles are often linked to modifications in their function. Endothelial cells store von Willebrand Factor (vWF), a glycoprotein essential to haemostasis in Weibel-Palade bodies (WPBs), cigar-shaped secretory granules that are generated in a wide range of sizes. We recently showed that forcing changes in the size of WPBs modifies the activity of this cargo. We now find that endothelial cells treated with statins produce shorter WPBs and that the vWF they release at exocytosis displays a reduced capability to recruit platelets to the endothelial cell surface. Investigating other functional consequences of size changes of WPBs, we also report that the endothelial surface-associated vWF formed at exocytosis recruits soluble plasma vWF and that this process is reduced by treatments that shorten WPBs, statins included. These results indicate that the post-exocytic adhesive activity of vWF towards platelets and plasma vWF at the endothelial surface reflects the size of their storage organelle. Our findings therefore show that changes in WPB size, by influencing the adhesive activity of its vWF cargo, may represent a novel mode of regulation of platelet aggregation at the vascular wall. PMID:27576551

  19. Serotonin-mediated modulation of hypoxia-induced intracellular calcium responses in glomus cells isolated from rat carotid body.

    PubMed

    Yokoyama, Takuya; Nakamuta, Nobuaki; Kusakabe, Tatsumi; Yamamoto, Yoshio

    2015-06-15

    In the present study, we examined serotonin (5-HT)-induced intracellular Ca(2+) ([Ca(2+)]i) responses to hypoxia in glomus cells isolated from carotid body (CB) of the rat. 5-HT did not induce any [Ca(2+)]i responses in clustered glomus cells during normoxia (21% O2), whereas, the perfusion of hypoxic solution (1% O2) induced repetitive increases in [Ca(2+)]i in the same specimens. The frequency and magnitude of hypoxia-induced [Ca(2+)]i changes observed in the glomus cells were enhanced in the presence of 5-HT, and this response was inhibited by the 5-HT2 receptor antagonist, ketanserin. Furthermore, RT-PCR analysis detected the expression of 5-HT1A, 5-HT1B, 5-HT1D, 5-HT1F, 5-HT2A, 5-HT2B, 5-HT3A, and 5-HT3B receptor mRNAs in extracts of the CB. These results suggest that 5-HT increases hypoxia-induced [Ca(2+)]i responses in glomus cells. 5-HT may elevate hypoxic responses in glomus cells in order to increase chemosensory activity of the CB.

  20. Weibel-Palade body size modulates the adhesive activity of its von Willebrand Factor cargo in cultured endothelial cells.

    PubMed

    Ferraro, Francesco; Mafalda Lopes da, Silva; Grimes, William; Lee, Hwee Kuan; Ketteler, Robin; Kriston-Vizi, Janos; Cutler, Daniel F

    2016-08-31

    Changes in the size of cellular organelles are often linked to modifications in their function. Endothelial cells store von Willebrand Factor (vWF), a glycoprotein essential to haemostasis in Weibel-Palade bodies (WPBs), cigar-shaped secretory granules that are generated in a wide range of sizes. We recently showed that forcing changes in the size of WPBs modifies the activity of this cargo. We now find that endothelial cells treated with statins produce shorter WPBs and that the vWF they release at exocytosis displays a reduced capability to recruit platelets to the endothelial cell surface. Investigating other functional consequences of size changes of WPBs, we also report that the endothelial surface-associated vWF formed at exocytosis recruits soluble plasma vWF and that this process is reduced by treatments that shorten WPBs, statins included. These results indicate that the post-exocytic adhesive activity of vWF towards platelets and plasma vWF at the endothelial surface reflects the size of their storage organelle. Our findings therefore show that changes in WPB size, by influencing the adhesive activity of its vWF cargo, may represent a novel mode of regulation of platelet aggregation at the vascular wall.

  1. Activation of group I metabotropic glutamate receptors enhances persistent sodium current and rhythmic bursting in main olfactory bulb external tufted cells

    PubMed Central

    Ennis, Matthew

    2013-01-01

    Rhythmically bursting olfactory bulb external tufted (ET) cells are thought to play a key role in synchronizing glomerular network activity to respiratory-driven sensory input. Whereas spontaneous bursting in these cells is intrinsically generated by interplay of several voltage-dependent currents, bursting strength and frequency can be modified by local intrinsic and centrifugal synaptic input. Activation of metabotropic glutamate receptors (mGluRs) engages a calcium-dependent cation current (ICAN) that increases rhythmic bursting, but mGluRs may also modulate intrinsic mechanisms involved in bursting. Here, we used patch-clamp electrophysiology in rat olfactory bulb slices to investigate whether mGluRs modulate two key intrinsic currents involved in ET cell burst initiation: persistent sodium (INaP) and hyperpolarization-activated cation (Ih) currents. Using a BAPTA-based internal solution to block ICAN, we found that the mGluR1/5 agonist DHPG enhanced INaP but did not alter Ih. INaP enhancement consisted of increased current at membrane potentials between −60 and −50 mV and a hyperpolarizing shift in activation threshold. Both effects would be predicted to shorten the interburst interval. In agreement, DHPG modestly depolarized (∼3.5 mV) ET cells and increased burst frequency without effect on other major burst parameters. This increase was inversely proportional to the basal burst rate such that slower ET cells exhibited the largest increases. This may enable ET cells with slow intrinsic burst rates to pace with faster sniff rates. Taken with other findings, these results indicate that multiple neurotransmitter mechanisms are engaged to fine-tune rhythmic ET cell bursting to context- and state-dependent changes in sniffing frequency. PMID:24225539

  2. Minocycline modulates cytokine and gene expression profiles in the brain after whole-body exposure to radiation.

    PubMed

    Mehrotra, Shalini; Pecaut, Michael J; Gridley, Daila S

    2014-01-01

    An effective countermeasure against radiation damage to normal tissues is urgently needed. The major goal of the present study was to determine if minocycline could modify the immunomodulatory effects of radiation on the brain. C57BL/6 mice were treated with minocycline intraperitoneally for 5 days beginning immediately before total-body exposure to 0, 1, 2 and 3 Gray (Gy) (60)Co γ-rays. Brains were collected on days 4 and 32 post-irradiation for cytokine and gene analyses. Minocycline treatment significantly increased the levels of interleukin (IL)-10, IL-15 and vascular endothelial growth factor (VEGF) in the brain on day 4 in one or more irradiated groups compared to radiation-alone (p<0.05). IL-10 is anti-inflammatory, IL-15 can prevent apoptosis and VEGF is nuroprotective. On day 32, the drug decreased IL-1β in the 2- Gy group (p<0.05 vs. 2-Gy alone); this cytokine is implicated in immune-related central nervous system pathologies. Microarray analysis of brains on day 32 showed that while radiation increased expression of inflammatory genes such as Il1f10, Il17, Tnfrsf11b, Tnfsf12, Il12b and Il1f8, these were no longer up-regulated in the minocycline-treated groups. Similarly, the pro-apoptotic gene Bik and nitric oxide synthase producer (Nostrin) were no longer up-regulated in the drug-treated groups. Pathway analysis based on gene data suggested that catenin-β1 and tumor suppressor-related transcription regulation were significantly activated by radiation and/or minocycline (activation z-score >2.0). Overall, the data warrant further testing of minocycline as a potential neuroprotectant against radiation-induced damage.

  3. Modulation of polyamine metabolic flux in adipose tissue alters the accumulation of body fat by affecting glucose homeostasis

    PubMed Central

    Liu, Chunli; Perez-Leal, Oscar; Barrero, Carlos; Zahedi, Kamyar; Soleimani, Manoocher; Porter, Carl

    2013-01-01

    The continued rise in obesity despite public education, awareness and policies indicates the need for mechanism-based therapeutic approaches to help control the disease. Our data, in conjunction with other studies, suggest an unexpected role for the polyamine catabolic enzyme spermidine/spermine-N1-acetyltransferase (SSAT) in fat homeostasis. Our previous studies showed that deletion of SSAT greatly exaggerates weight gain and that the transgenic overexpression suppresses weight gain in mice on a high-fat diet. This discovery is substantial but the underlying molecular linkages are only vaguely understood. Here, we used a comprehensive systems biology approach, on white adipose tissue (WAT), to discover that the partition of acetyl-CoA towards polyamine catabolism alters glucose homeostasis and hence, fat accumulation. Comparative proteomics and antibody-based expression studies of WAT in SSAT knockout, wild type and transgenic mice identified nine proteins with an increasing gradient across the genotypes, all of which correlate with acetyl-CoA consumption in polyamine acetylation. Adipose-specific SSAT knockout mice and global SSAT knockout mice on a high-fat diet exhibited similar growth curves and proteomic patterns in their WAT, confirming that attenuated consumption of acetyl-CoA in acetylation of polyamines in adipose tissue drives the obese phenotype of these mice. Analysis of protein expression indicated that the identified changes in the levels of proteins regulating acetyl-CoA consumption occur via the AMP-activated protein kinase pathway. Together, our data suggest that differential expression of SSAT markedly alters acetyl-CoA levels, which in turn trigger a global shift in glucose metabolism in adipose tissue, thus affecting the accumulation of body fat. PMID:23881108

  4. Diel rhythmicity in amino acid uptake by Prochlorococcus.

    PubMed

    Mary, Isabelle; Garczarek, Laurence; Tarran, Glen A; Kolowrat, Christian; Terry, Matthew J; Scanlan, David J; Burkill, Peter H; Zubkov, Mikhail V

    2008-08-01

    The marine cyanobacterium Prochlorococcus, the most abundant phototrophic organism on Earth, numerically dominates the phytoplankton in nitrogen (N)-depleted oceanic gyres. Alongside inorganic N sources such as nitrite and ammonium, natural populations of this genus also acquire organic N, specifically amino acids. Here, we investigated using isotopic tracer and flow cytometric cell sorting techniques whether amino acid uptake by Prochlorococcus is subject to a diel rhythmicity, and if so, whether this was linked to a specific cell cycle stage. We observed, in contrast to diurnally similar methionine uptake rates by Synechococcus cells, obvious diurnal rhythms in methionine uptake by Prochlorococcus cells in the tropical Atlantic. These rhythms were confirmed using reproducible cyclostat experiments with a light-synchronized axenic Prochlorococcus (PCC9511 strain) culture and (35)S-methionine and (3)H-leucine tracers. Cells acquired the tracers at lower rates around dawn and higher rates around dusk despite >10(4) times higher concentration of ammonium in the medium, presumably because amino acids can be directly incorporated into protein. Leucine uptake rates by cells in the S+G(2) cell cycle stage were consistently 2.2 times higher than those of cells at the G(1) stage. Furthermore, S+G(2) cells upregulated amino acid uptake 3.5 times from dawn to dusk to boost protein synthesis prior to cell division. Because Prochlorococcus populations can account from 13% at midday to 42% at dusk of total microbial uptake of methionine and probably of other amino acids in N-depleted oceanic waters, this genus exerts diurnally variable, strong competitive pressure on other bacterioplankton populations.

  5. Rhythmic Manipulation of Objects with Complex Dynamics: Predictability over Chaos

    PubMed Central

    Nasseroleslami, Bahman; Hasson, Christopher J.; Sternad, Dagmar

    2014-01-01

    The study of object manipulation has been largely confined to discrete tasks, where accuracy, mechanical effort, or smoothness were examined to explain subjects' preferred movements. This study investigated a rhythmic manipulation task, which involved continuous interaction with a nonlinear object that led to unpredictable object behavior. Using a simplified virtual version of the task of carrying a cup of coffee, we studied how this unpredictable object behavior affected the selected strategies. The experiment was conducted in a virtual set-up, where subjects moved a cup with a ball inside, modeled by cart-and-pendulum dynamics. Inverse dynamics calculations of the system showed that performing the task with different amplitudes and relative phases required different force profiles and rendered the object's dynamics with different degrees of predictability (quantified by Mutual Information between the applied force and the cup kinematics and its sensitivity). Subjects (n = 8) oscillated the virtual cup between two targets via a robotic manipulandum, paced by a metronome at 1 Hz for 50 trials, each lasting 45 s. They were free to choose their movement amplitude and relative phase between the ball and cup. Experimental results showed that subjects increased their movement amplitudes, which rendered the interactions with the object more predictable and with lower sensitivity to the execution variables. These solutions were associated with higher average exerted force and lower object smoothness, contradicting common expectations from studies on discrete object manipulation and unrestrained movements. Instead, the findings showed that humans selected strategies with higher predictability of interaction dynamics. This finding expressed that humans seek movement strategies where force and kinematics synchronize to repeatable patterns that may require less sensorimotor information processing. PMID:25340581

  6. Triaxial modulation of the acceleration induced in the lower extremity during whole-body vibration training: a pilot study.

    PubMed

    Cook, David P; Mileva, Katya N; James, Darren C; Zaidell, Lisa N; Goss, Victor G; Bowtell, Joanna L

    2011-02-01

    The purpose of the present study was to quantify vibration transmissibility through the lower extremity during exercise on a whole-body vibration (WBV) platform. Six healthy adults completed 20 trials of 30-second static squat exercise at 30 or 40 degrees of knee flexion angle on a WBV platform working at combinations of 5 frequencies (VF: 20, 25, 30, 35, 40 Hz) and 2 amplitudes (VA: low, 1.5 mm or high, 3 mm). Accelerations induced by the platform were recorded simultaneously at the shank and the thigh using triaxial accelerometers positioned at the segmental center of mass. Root-mean-square (RMS) acceleration amplitude and transmission ratios between the platform and the leg segments were calculated and compared between the experimental conditions. An alpha level of 0.05 was set to establish significance. Shank vertical acceleration was greatest at the lower VF (p = 0.028), higher VA (p = 0.028), and deeper squat (p = 0.048). Thigh vertical acceleration was not affected by depth of squat (p = 0.25), but it was greatest at higher VA (p = 0.046) and lower VF (p = 0.028). Medial-lateral shank acceleration was greatest at higher VF and deeper squat (both p = 0.046) and at higher VA (p = 0.028). Medial-lateral thigh acceleration was positively related to both VF (p = 0.046) and VA (p = 0.028) but was not affected by knee angle (p = 0.46). Anterior-posterior shank acceleration was higher at deeper squat (p = 0.046) and at lower VF and higher VA (both p = 0.028). Anterior-posterior thigh acceleration was related positively to the VA (p = 0.028), inversely to the VF (p = 0.028), and not dependent on knee angle (p = 0.75). Identification of specific vibration parameters and posture, which underpin WBV training efficacy, will enable coaches and athletes to design WBV training programs to specifically target shank or thigh muscles for enhanced performance.

  7. Active inclusion bodies of acid phosphatase PhoC: aggregation induced by GFP fusion and activities modulated by linker flexibility

    PubMed Central

    2013-01-01

    Background Biologically active inclusion bodies (IBs) have gained much attention in recent years. Fusion with IB-inducing partner has been shown to be an efficient strategy for generating active IBs. To make full use of the advantages of active IBs, one of the key issues will be to improve the activity yield of IBs when expressed in cells, which would need more choices on IB-inducing fusion partners and approaches for engineering IBs. Green fluorescent protein (GFP) has been reported to aggregate when overexpressed, but GFP fusion has not been considered as an IB-inducing approach for these fusion proteins so far. In addition, the role of linker in fusion proteins has been shown to be important for protein characteristics, yet impact of linker on active IBs has never been reported. Results Here we report that by fusing GFP and acid phosphatase PhoC via a linker region, the resultant PhoC-GFPs were expressed largely as IBs. These IBs show high levels of specific fluorescence and specific PhoC activities (phosphatase and phosphotransferase), and can account for up to over 80% of the total PhoC activities in the cells. We further demonstrated that the aggregation of GFP moiety in the fusion protein plays an essential role in the formation of PhoC-GFP IBs. In addition, PhoC-GFP IBs with linkers of different flexibility were found to exhibit different levels of activities and ratios in the cells, suggesting that the linker region can be utilized to manipulate the characteristics of active IBs. Conclusions Our results show that active IBs of PhoC can be generated by GFP fusion, demonstrating for the first time the potential of GFP fusion to induce active IB formation of another soluble protein. We also show that the linker sequence in PhoC-GFP fusion proteins plays an important role on the regulation of IB characteristics, providing an alternative and important approach for engineering of active IBs with the goal of obtaining high activity yield of IBs. PMID:23497261

  8. Locomotor-Like Leg Movements Evoked by Rhythmic Arm Movements in Humans

    PubMed Central

    Sylos-Labini, Francesca; Ivanenko, Yuri P.; MacLellan, Michael J.; Cappellini, Germana; Poppele, Richard E.; Lacquaniti, Francesco

    2014-01-01

    Motion of the upper limbs is often coupled to that of the lower limbs in human bipedal locomotion. It is unclear, however, whether the functional coupling between upper and lower limbs is bi-directional, i.e. whether arm movements can affect the lumbosacral locomotor circuitry. Here we tested the effects of voluntary rhythmic arm movements on the lower limbs. Participants lay horizontally on their side with each leg suspended in an unloading exoskeleton. They moved their arms on an overhead treadmill as if they walked on their hands. Hand-walking in the antero-posterior direction resulted in significant locomotor-like movements of the legs in 58% of the participants. We further investigated quantitatively the responses in a subset of the responsive subjects. We found that the electromyographic (EMG) activity of proximal leg muscles was modulated over each cycle with a timing similar to that of normal locomotion. The frequency of kinematic and EMG oscillations in the legs typically differed from that of arm oscillations. The effect of hand-walking was direction specific since medio-lateral arm movements did not evoke appreciably leg air-stepping. Using externally imposed trunk movements and biomechanical modelling, we ruled out that the leg movements associated with hand-walking were mainly due to the mechanical transmission of trunk oscillations. EMG activity in hamstring muscles associated with hand-walking often continued when the leg movements were transiently blocked by the experimenter or following the termination of arm movements. The present results reinforce the idea that there exists a functional neural coupling between arm and legs. PMID:24608249

  9. Short-Term Synaptic Plasticity at Interneuronal Synapses Could Sculpt Rhythmic Motor Patterns

    PubMed Central

    Jia, Yan; Parker, David

    2016-01-01

    The output of a neuronal network depends on the organization and functional properties of its component cells and synapses. While the characterization of synaptic properties has lagged cellular analyses, a potentially important aspect in rhythmically active networks is how network synapses affect, and are in turn affected by, network activity. This could lead to a potential circular interaction where short-term activity-dependent synaptic plasticity is both influenced by and influences the network output. The analysis of synaptic plasticity in the lamprey locomotor network was extended here to characterize the short-term plasticity of connections between network interneurons and to try and address its potential network role. Paired recordings from identified interneurons in quiescent networks showed synapse-specific synaptic properties and plasticity that supported the presence of two hemisegmental groups that could influence bursting: depression in an excitatory interneuron group, and facilitation in an inhibitory feedback circuit. The influence of activity-dependent synaptic plasticity on network activity was investigated experimentally by changing Ringer Ca2+ levels, and in a simple computer model. A potential caveat of the experimental analyses was that changes in Ringer Ca2+ (and compensatory adjustments in Mg2+ in some cases) could alter several other cellular and synaptic properties. Several of these properties were tested, and while there was some variability, these were not usually significantly affected by the Ringer changes. The experimental analyses suggested that depression of excitatory inputs had the strongest influence on the patterning of network activity. The simulation supported a role for this effect, and also suggested that the inhibitory facilitating group could modulate the influence of the excitatory synaptic depression. Short-term activity-dependent synaptic plasticity has not generally been considered in spinal cord models. These results

  10. Interactive Rhythmic Cue Facilitates Gait Relearning in Patients with Parkinson's Disease

    PubMed Central

    Uchitomi, Hirotaka; Ota, Leo; Ogawa, Ken-ichiro; Orimo, Satoshi; Miyake, Yoshihiro

    2013-01-01

    To develop a method for cooperative human gait training, we investigated whether interactive rhythmic cues could improve the gait performance of Parkinson's disease patients. The interactive rhythmic cues ware generated based on the mutual entrainment between the patient's gait rhythms and the cue rhythms input to the patient while the patient walked. Previously, we found that the dynamic characteristics of stride interval fluctuation in Parkinson's disease patients were improved to a healthy 1/f fluctuation level using interactive rhythmic cues and that this effect was maintained in the short term. However, two problems remained in our previous study. First, it was not clear whether the key factor underpinning the effect was the mutual entrainment between the gait rhythms and the cue rhythms or the rhythmic cue fluctuation itself. Second, it was not clear whether or not the gait restoration was maintained longitudinally and was relearned after repeating the cue-based gait training. Thus, the present study clarified these issues using 32 patients who participated in a four-day experimental program. The patients were assigned randomly to one of four experimental groups with the following rhythmic cues: (a) interactive rhythmic cue, (b) fixed tempo cue, (c) 1/f fluctuating tempo cue, and (d) no cue. It has been reported that the 1/f fluctuation of stride interval in healthy gait is absent in Parkinson's disease patients. Therefore, we used this dynamic characteristic as an evaluation index to analyze gait relearning in the four different conditions. We observed a significant effect in condition (a) that the gait fluctuation of the patients gradually returned to a healthy 1/f fluctuation level, whereas this did not occur in the other conditions. This result suggests that the mutual entrainment can facilitate gait relearning effectively. It is expected that interactive rhythmic cues will be widely applicable in the fields of rehabilitation and assistive technology

  11. Endogenous rhythmic growth in oak trees is regulated by internal clocks rather than resource availability.

    PubMed

    Herrmann, S; Recht, S; Boenn, M; Feldhahn, L; Angay, O; Fleischmann, F; Tarkka, M T; Grams, T E E; Buscot, F

    2015-12-01

    Common oak trees display endogenous rhythmic growth with alternating shoot and root flushes. To explore the mechanisms involved, microcuttings of the Quercus robur L. clone DF159 were used for (13)C/(15)N labelling in combination with RNA sequencing (RNASeq) transcript profiling of shoots and roots. The effect of plant internal resource availability on the rhythmic growth of the cuttings was tested through inoculation with the ectomycorrhizal fungus Piloderma croceum. Shoot and root flushes were related to parallel shifts in above- and below-ground C and, to a lesser extent, N allocation. Increased plant internal resource availability by P. croceum inoculation with enhanced plant growth affected neither the rhythmic growth nor the associated resource allocation patterns. Two shifts in transcript abundance were identified during root and shoot growth cessation, and most concerned genes were down-regulated. Inoculation with P. croceum suppressed these transcript shifts in roots, but not in shoots. To identify core processes governing the rhythmic growth, functions [Gene Ontology (GO) terms] of the genes differentially expressed during the growth cessation in both leaves and roots of non-inoculated plants and leaves of P. croceum-inoculated plants were examined. Besides genes related to resource acquisition and cell development, which might reflect rather than trigger rhythmic growth, genes involved in signalling and/or regulated by the circadian clock were identified. The results indicate that rhythmic growth involves dramatic oscillations in plant metabolism and gene regulation between below- and above-ground parts. Ectomycorrhizal symbiosis may play a previously unsuspected role in smoothing these oscillations without modifying the rhythmic growth pattern.

  12. Acute Reversal of Phospholamban Inhibition Facilitates the Rhythmic Whole-cell Propagating Calcium Waves in Isolated Ventricular Myocytes

    PubMed Central

    Chan, Yi-Hsin; Tsai, Wei-Chung; Song, Zhen; Ko, Christopher Y.; Qu, Zhilin; Weiss, James N.; Lin, Shien-Fong; Chen, Peng-Sheng; Jones, Larry R.; Chen, Zhenhui

    2015-01-01

    Phospholamban (PLB) inhibits the activity of cardiac sarcoplasmic reticulum (SR) Ca2+-ATPase (SERCA2a). Phosphorylation of PLB during sympathetic activation reverses SERCA2a inhibition, increasing SR Ca2+ uptake. However, sympathetic activation also modulates multiple other intracellular targets in ventricular myocytes (VMs), making it impossible to determine the specific effects of reversal of PLB inhibition on the spontaneous SR Ca2+ release. Therefore, it remains unclear how PLB regulates rhythmic activity in VMs. Here we used the Fab fragment of 2D12, a monoclonal anti-PLB antibody, to test how acute reversal of PLB inhibition affects the spontaneous SR Ca2+ release in normal VMs. Ca2+ sparks and spontaneous Ca2+ waves (SCWs) were recorded in the line-scan mode of confocal microscopy using the Ca2+ fluorescent dye Fluo-4 in isolated permeabilized mouse VMs. Fab, which reverses PLB inhibition, significantly increased the frequency, amplitude, and spatial/temporal spread of Ca2+ sparks in VMs exposed to 50 nM free [Ca2+]. At physiological diastolic free [Ca2+] (100–200 nM), Fab facilitated the formation of whole-cell propagating SCWs. At higher free [Ca2+], Fab increased the frequency and velocity, but decreased the decay time of the SCWs. cAMP had little additional effect on the frequency or morphology of Ca2+ sparks or SCWs after Fab addition. These findings were complemented by computer simulations. In conclusion, acute reversal of PLB inhibition alone significantly increased the spontaneous SR Ca2+ release, leading to the facilitation and organization of whole-cell propagating SCWs in normal VMs. PLB thus plays a key role in subcellular Ca2+ dynamics and rhythmic activity of VMs. PMID:25596331

  13. Effect of angiotensin II on rhythmic per2 expression in the suprachiasmatic nucleus and heart and daily rhythm of activity in Wistar rats.

    PubMed

    Herichová, Iveta; Šoltésová, Dorota; Szántóová, Kristína; Mravec, Boris; Neupauerová, Denisa; Veselá, Anna; Zeman, Michal

    2013-09-10

    Endogenous daily rhythms are generated by the hierarchically organized circadian system predominantly synchronized by the external light (L): dark (D) cycle. During recent years several humoral signals have been found to influence the generation and manifestation of daily rhythm. Since most studies have been performed under in vitro conditions, the mechanisms employed under in vivo conditions need to be investigated. Our study focused on angiotensin II (angII)-mediated regulation of Per2 expression in the suprachiasmatic nuclei (SCN) and heart and spontaneous locomotor activity in Wistar rats under synchronized conditions. Angiotensin II was infused (100ng/kg/min) via subcutaneously implanted osmotic minipumps for 7 or 28days. Samples were taken in 4-h intervals during a 24hcycle and after a light pulse applied in the first and second part of the dark phase. Gene expression was measured using real time PCR. Locomotor activity was monitored using an infrared camera with a remote control installed in the animal facility. Seven days of angII infusion caused an increase in blood pressure and heart/body weight index and 28days of angII infusion also increased water intake in comparison with controls. We observed a distinct daily rhythm in Per2 expression in the SCN and heart of control rats and infused rats. Seven days of angII infusion did not influence Per2 expression in the heart. 28days of angII treatment caused significant phase advance and a decrease in nighttime expression of Per2 and influenced expression of clock controlled genes Rev-erb alpha and Dbp in the heart compared to the control. Four weeks of angII infusion decreased the responsiveness of Per2 expression in the SCN to a light pulse at the end of the dark phase of the 24hcycle. Expression of mRNA coding angiotensin-converting enzyme (ACE) and angiotensin-converting enzyme 2 (ACE2) showed a daily rhythm in the heart of control rats. Four weeks of angII infusion caused a decrease in amplitude of rhythmic

  14. Dose Gradient Near Target-Normal Structure Interface for Nonisocentric CyberKnife and Isocentric Intensity-Modulated Body Radiotherapy for Prostate Cancer

    SciTech Connect

    Hossain, Sabbir; Xia Ping; Huang, Kim; Descovich, Martina; Chuang, Cynthia; Gottschalk, Alexander R.; Roach, Mack; Ma Lijun

    2010-09-01

    Purpose: The treatment planning quality between nonisocentric CyberKnife (CK) and isocentric intensity modulation treatment was studied for hypofractionated prostate body radiotherapy. In particular, the dose gradient across the target and the critical structures such as the rectum and bladder was characterized. Methods and Materials: In the present study, patients treated with CK underwent repeat planning for nine fixed-field intensity-modulated radiotherapy (IMRT) using identical contour sets and dose-volume constraints. To calculate the dose falloff, the clinical target volume contours were expanded 30 mm anteriorly and posteriorly and 50 mm uniformly in other directions for all patients in the CK and IMRT plans. Results: We found that all the plans satisfied the dose-volume constraints, with the CK plans showing significantly better conformity than the IMRT plans at a relative greater dose inhomogeneity. The rectal and bladder volumes receiving a low dose were also lower for CK than for IMRT. The average conformity index, the ratio of the prescription isodose volume and clinical target volume, was 1.18 {+-} 0.08 for the CK plans vs. 1.44 {+-} 0.11 for the IMRT plans. The average homogeneity index, the ratio of the maximal dose and the prescribed dose to the clinical target volume, was 1.45 {+-} 0.12 for the CK plans vs. 1.28 {+-} 0.06 for the IMRT plans. The average percentage of dose falloff was 2.9% {+-} 0.8%/mm for CK and 3.1% {+-} 1.0%/mm for IMRT in the anterior direction, 3.8% {+-} 1.6%/mm for CK and 3.2% {+-} 1.9%/mm for IMRT in the posterior direction, and 3.6% {+-} 0.4% for CK and 3.6% {+-} 0.4% for IMRT in all directions. Conclusion: Nonisocentric CK was as capable of producing equivalent fast dose falloff as high-number fixed-field IMRT delivery.

  15. Proton Arc Reduces Range Uncertainty Effects and Improves Conformality Compared With Photon Volumetric Modulated Arc Therapy in Stereotactic Body Radiation Therapy for Non-Small Cell Lung Cancer

    SciTech Connect

    Seco, Joao; Gu, Guan; Marcelos, Tiago; Kooy, Hanne; Willers, Henning

    2013-09-01

    Purpose: To describe, in a setting of non-small cell lung cancer (NSCLC), the theoretical dosimetric advantages of proton arc stereotactic body radiation therapy (SBRT) in which the beam penumbra of a rotating beam is used to reduce the impact of range uncertainties. Methods and Materials: Thirteen patients with early-stage NSCLC treated with proton SBRT underwent repeat planning with photon volumetric modulated arc therapy (Photon-VMAT) and an in-house-developed arc planning approach for both proton passive scattering (Passive-Arc) and intensity modulated proton therapy (IMPT-Arc). An arc was mimicked with a series of beams placed at 10° increments. Tumor and organ at risk doses were compared in the context of high- and low-dose regions, represented by volumes receiving >50% and <50% of the prescription dose, respectively. Results: In the high-dose region, conformality index values are 2.56, 1.91, 1.31, and 1.74, and homogeneity index values are 1.29, 1.22, 1.52, and 1.18, respectively, for 3 proton passive scattered beams, Passive-Arc, IMPT-Arc, and Photon-VMAT. Therefore, proton arc leads to a 30% reduction in the 95% isodose line volume to 3-beam proton plan, sparing surrounding organs, such as lung and chest wall. For chest wall, V30 is reduced from 21 cm{sup 3} (3 proton beams) to 11.5 cm{sup 3}, 12.9 cm{sup 3}, and 8.63 cm{sup 3} (P=.005) for Passive-Arc, IMPT-Arc, and Photon-VMAT, respectively. In the low-dose region, the mean lung dose and V20 of the ipsilateral lung are 5.01 Gy(relative biological effectiveness [RBE]), 4.38 Gy(RBE), 4.91 Gy(RBE), and 5.99 Gy(RBE) and 9.5%, 7.5%, 9.0%, and 10.0%, respectively, for 3-beam, Passive-Arc, IMPT-Arc, and Photon-VMAT, respectively. Conclusions: Stereotactic body radiation therapy with proton arc and Photon-VMAT generate significantly more conformal high-dose volumes than standard proton SBRT, without loss of coverage of the tumor and with significant sparing of nearby organs, such as chest wall. In addition

  16. Processing Rhythmic Pattern during Chinese Sentence Reading: An Eye Movement Study.

    PubMed

    Luo, Yingyi; Duan, Yunyan; Zhou, Xiaolin

    2015-01-01

    Prosodic constraints play a fundamental role during both spoken sentence comprehension and silent reading. In Chinese, the rhythmic pattern of the verb-object (V-O) combination has been found to rapidly affect the semantic access/integration process during sentence reading (Luo and Zhou, 2010). Rhythmic pattern refers to the combination of words with different syllabic lengths, with certain combinations disallowed (e.g., [2 + 1]; numbers standing for the number of syllables of the verb and the noun respectively) and certain combinations preferred (e.g., [1 + 1] or [2 + 2]). This constraint extends to the situation in which the combination is used to modify other words. A V-O phrase could modify a noun by simply preceding it, forming a V-O-N compound; when the verb is disyllabic, however, the word order has to be O-V-N and the object is preferred to be disyllabic. In this study, we investigated how the reader processes the rhythmic pattern and word order information by recording the reader's eye-movements. We created four types of sentences by crossing rhythmic pattern and word order in compounding. The compound, embedding a disyllabic verb, could be in the correct O-V-N or the incorrect V-O-N order; the object could be disyllabic or monosyllabic. We found that the reader spent more time and made more regressions on and after the compounds when either type of anomaly was detected during the first pass reading. However, during re-reading (after all the words in the sentence have been viewed), less regressive eye movements were found for the anomalous rhythmic pattern, relative to the correct pattern; moreover, only the abnormal rhythmic pattern, not the violated word order, influenced the regressive eye movements. These results suggest that while the processing of rhythmic pattern and word order information occurs rapidly during the initial reading of the sentence, the process of recovering from the rhythmic pattern anomaly may ease the reanalysis processing at the

  17. Processing Rhythmic Pattern during Chinese Sentence Reading: An Eye Movement Study

    PubMed Central

    Luo, Yingyi; Duan, Yunyan; Zhou, Xiaolin

    2015-01-01

    Prosodic constraints play a fundamental role during both spoken sentence comprehension and silent reading. In Chinese, the rhythmic pattern of the verb-object (V-O) combination has been found to rapidly affect the semantic access/integration process during sentence reading (Luo and Zhou, 2010). Rhythmic pattern refers to the combination of words with different syllabic lengths, with certain combinations disallowed (e.g., [2 + 1]; numbers standing for the number of syllables of the verb and the noun respectively) and certain combinations preferred (e.g., [1 + 1] or [2 + 2]). This constraint extends to the situation in which the combination is used to modify other words. A V-O phrase could modify a noun by simply preceding it, forming a V-O-N compound; when the verb is disyllabic, however, the word order has to be O-V-N and the object is preferred to be disyllabic. In this study, we investigated how the reader processes the rhythmic pattern and word order information by recording the reader's eye-movements. We created four types of sentences by crossing rhythmic pattern and word order in compounding. The compound, embedding a disyllabic verb, could be in the correct O-V-N or the incorrect V-O-N order; the object could be disyllabic or monosyllabic. We found that the reader spent more time and made more regressions on and after the compounds when either type of anomaly was detected during the first pass reading. However, during re-reading (after all the words in the sentence have been viewed), less regressive eye movements were found for the anomalous rhythmic pattern, relative to the correct pattern; moreover, only the abnormal rhythmic pattern, not the violated word order, influenced the regressive eye movements. These results suggest that while the processing of rhythmic pattern and word order information occurs rapidly during the initial reading of the sentence, the process of recovering from the rhythmic pattern anomaly may ease the reanalysis processing at the

  18. Enhanced musical rhythmic perception in Turkish early and late learners of German.

    PubMed

    Roncaglia-Denissen, M Paula; Schmidt-Kassow, Maren; Heine, Angela; Vuust, Peter; Kotz, Sonja A

    2013-01-01

    As language rhythm relies partly on general acoustic properties, such as intensity and duration, mastering two languages with distinct rhythmic properties (i.e., stress position) may enhance musical rhythm perception. We investigated whether competence in a second language (L2) with different rhythmic properties than a L1 affects musical rhythm aptitude. Turkish early (TELG) and late learners (TLLG) of German were compared to German late L2 learners of English (GLE) regarding their musical rhythmic aptitude. While Turkish and German present distinct linguistic rhythm and metric properties, German and English are rather similar in this regard. To account for inter-individual differences, we measured participants' short-term and working memory (WM) capacity, melodic aptitude, and time they spent listening to music. Both groups of Turkish L2 learners of German perceived rhythmic variations significantly better than German L2 learners of English. No differences were found between early and late learners' performance. Our findings suggest that mastering two languages with different rhythmic properties enhances musical rhythm perception, providing further evidence of shared cognitive resources between language and music.

  19. Separate representations of dynamics in rhythmic and discrete movements: evidence from motor learning.

    PubMed

    Howard, Ian S; Ingram, James N; Wolpert, Daniel M

    2011-04-01

    Rhythmic and discrete arm movements occur ubiquitously in everyday life, and there is a debate as to whether these two classes of movements arise from the same or different underlying neural mechanisms. Here we examine interference in a motor-learning paradigm to test whether rhythmic and discrete movements employ at least partially separate neural representations. Subjects were required to make circular movements of their right hand while they were exposed to a velocity-dependent force field that perturbed the circularity of the movement path. The direction of the force-field perturbation reversed at the end of each block of 20 revolutions. When subjects made only rhythmic or only discrete circular movements, interference was observed when switching between the two opposing force fields. However, when subjects alternated between blocks of rhythmic and discrete movements, such that each was uniquely associated with one of the perturbation directions, interference was significantly reduced. Only in this case did subjects learn to corepresent the two opposing perturbations, suggesting that different neural resources were employed for the two movement types. Our results provide further evidence that rhythmic and discrete movements employ at least partially separate control mechanisms in the motor system.

  20. The effects of rhythmic sensory cues on the temporal dynamics of human gait.

    PubMed

    Sejdić, Ervin; Fu, Yingying; Pak, Alison; Fairley, Jillian A; Chau, Tom

    2012-01-01

    Walking is a complex, rhythmic task performed by the locomotor system. However, natural gait rhythms can be influenced by metronomic auditory stimuli, a phenomenon of particular interest in neurological rehabilitation. In this paper, we examined the effects of aural, visual and tactile rhythmic cues on the temporal dynamics associated with human gait. Data were collected from fifteen healthy adults in two sessions. Each session consisted of five 15-minute trials. In the first trial of each session, participants walked at their preferred walking speed. In subsequent trials, participants were asked to walk to a metronomic beat, provided through visually, aurally, tactile or all three cues (simultaneously and in sync), the pace of which was set to the preferred walking speed of the first trial. Using the collected data, we extracted several parameters including: gait speed, mean stride interval, stride interval variability, scaling exponent and maximum Lyapunov exponent. The extracted parameters showed that rhythmic sensory cues affect the temporal dynamics of human gait. The auditory rhythmic cue had the greatest influence on the gait parameters, while the visual cue had no statistically significant effect on the scaling exponent. These results demonstrate that visual rhythmic cues could be considered as an alternative cueing modality in rehabilitation without concern of adversely altering the statistical persistence of walking.

  1. Interactive rhythmic auditory stimulation reinstates natural 1/f timing in gait of Parkinson's patients.

    PubMed

    Hove, Michael J; Suzuki, Kazuki; Uchitomi, Hirotaka; Orimo, Satoshi; Miyake, Yoshihiro

    2012-01-01

    Parkinson's disease (PD) and basal ganglia dysfunction impair movement timing, which leads to gait instability and falls. Parkinsonian gait consists of random, disconnected stride times--rather than the 1/f structure observed in healthy gait--and this randomness of stride times (low fractal scaling) predicts falling. Walking with fixed-tempo Rhythmic Auditory Stimulation (RAS) can improve many aspects of gait timing; however, it lowers fractal scaling (away from healthy 1/f structure) and requires attention. Here we show that interactive rhythmic auditory stimulation reestablishes healthy gait dynamics in PD patients. In the experiment, PD patients and healthy participants walked with a) no auditory stimulation, b) fixed-tempo RAS, and c) interactive rhythmic auditory stimulation. The interactive system used foot sensors and nonlinear oscillators to track and mutually entrain with the human's step timing. Patients consistently synchronized with the interactive system, their fractal scaling returned to levels of healthy participants, and their gait felt more stable to them. Patients and healthy participants rarely synchronized with fixed-tempo RAS, and when they did synchronize their fractal scaling declined from healthy 1/f levels. Five minutes after removing the interactive rhythmic stimulation, the PD patients' gait retained high fractal scaling, suggesting that the interaction stabilized the internal rhythm generating system and reintegrated timing networks. The experiment demonstrates that complex interaction is important in the (re)emergence of 1/f structure in human behavior and that interactive rhythmic auditory stimulation is a promising therapeutic tool for improving gait of PD patients.

  2. The generation of rhythmic activity in dissociated cultures of rat spinal cord.

    PubMed

    Streit, J; Tscherter, A; Heuschkel, M O; Renaud, P

    2001-07-01

    Locomotion in vertebrates is controlled by central pattern generators in the spinal cord. The roles of specific network architecture and neuronal properties in rhythm generation by such spinal networks are not fully understood. We have used multisite recording from dissociated cultures of embryonic rat spinal cord grown on multielectrode arrays to investigate the patterns of spontaneous activity in randomised spinal networks. We were able to induce similar patterns of rhythmic activity in dissociated cultures as in slice cultures, although not with the same reliability and not always with the same protocols. The most reliable rhythmic activity was induced when a partial disinhibition of the network was combined with an increase in neuronal excitability, suggesting that both recurrent synaptic excitation and neuronal excitability contribute to rhythmogenesis. During rhythmic activity, bursts started at several sites and propagated in variable ways. However, the predominant propagation patterns were independent of the protocol used to induce rhythmic activity. When synaptic transmission was blocked by CNQX, APV, strychnine and bicuculline, asynchronous low-rate activity persisted at approximately 50% of the electrodes and approximately 70% of the sites of burst initiation. Following the bursts, the activity in the interval was transiently suppressed below the level of intrinsic activity. The degree of suppression was proportional to the amount of activity in the preceding burst. From these findings we conclude that rhythmic activity in spinal cultures is controlled by the interplay of intrinsic neuronal activity and recurrent excitation in neuronal networks without the need for a specific architecture.

  3. Peripheral multidendritic sensory neurons are necessary for rhythmic locomotion behavior in Drosophila larvae

    PubMed Central

    Song, Wei; Onishi, Maika; Jan, Lily Yeh; Jan, Yuh Nung

    2007-01-01

    From breathing to walking, rhythmic movements encompass physiological processes important across the entire animal kingdom. It is thought by many that the generation of rhythmic behavior is operated by a central pattern generator (CPG) and does not require peripheral sensory input. Sensory feedback is, however, required to modify or coordinate the motor activity in response to the circumstances of actual movement. In contrast to this notion, we report here that sensory input is necessary for the generation of Drosophila larval locomotion, a form of rhythmic behavior. Blockage of all peripheral sensory inputs resulted in cessation of larval crawling. By conditionally silencing various subsets of larval peripheral sensory neurons, we identified the multiple dendritic (MD) neurons as the neurons essential for the generation of rhythmic peristaltic locomotion. By recording the locomotive motor activities, we further demonstrate that removal of MD neuron input disrupted rhythmic motor firing pattern in a way that prolonged the stereotyped segmental motor firing duration and prevented the propagation of posterior to anterior segmental motor firing. These findings reveal that MD sensory neuron input is a necessary component in the neural circuitry that generates larval locomotion. PMID:17360325

  4. Fictive rhythmic motor patterns produced by the tail spinal cord in salamanders.

    PubMed

    Charrier, V; Cabelguen, J-M

    2013-01-01

    Most investigations into the role of the body axis in vertebrate locomotion have focused on the trunk, although in most tetrapods, the tail also plays an active role. In salamanders, the tail contributes to propulsion during swimming and to dynamic balance and maneuverability during terrestrial locomotion. The aim of the present study was to obtain information concerning the neural mechanisms that produce tail muscle contractions during locomotion in the salamander Pleurodeles waltlii. We recorded the ventral root activities in in vitro spinal cord preparations in which locomotor-like activity was induced via bath application of N-methyl-d-aspartate (20μM) and d-serine (10μM). Recordings showed that the tail spinal cord is capable of producing propagated waves of motor activity that alternate between the left and right sides. Lesion experiments further revealed that the tail rhythmogenic network is composed of a double chain of identical hemisegmental oscillators. Finally, using spinal cord preparations bathed in a chamber partitioned into two pools, we revealed efficient short-distance coupling between the trunk and tail networks. Together, our results demonstrate the existence of a pattern generator for rhythmic tail movements in the salamander and show that the global architecture of the tail network is similar to that previously proposed for the mid-trunk locomotor network in the salamander. Our findings further support the view that salamanders can control their trunk and tail independently during stepping movements. The relevance of our results in relation to the generation of tail muscle contractions in freely moving salamanders is discussed.

  5. Meal Time Shift Disturbs Circadian Rhythmicity along with Metabolic and Behavioral Alterations in Mice

    PubMed Central

    Noh, Jong-Yun; Kim, Mi-Hee; Son, Gi Hoon; Kim, Kyungjin; Kim, Chang-Ju; Pak, Youngmi Kim; Cho, Sehyung

    2012-01-01

    In modern society, growing numbers of people are engaged in various forms of shift works or trans-meridian travels. Such circadian misalignment is known to disturb endogenous diurnal rhythms, which may lead to harmful physiological consequences including metabolic syndrome, obesity, cancer, cardiovascular disorders, and gastric disorders as well as other physical and mental disorders. However, the precise mechanism(s) underlying these changes are yet unclear. The present work, therefore examined the effects of 6 h advance or delay of usual meal time on diurnal rhythmicities in home cage activity (HCA), body temperature (BT), blood metabolic markers, glucose homeostasis, and expression of genes that are involved in cholesterol homeostasis by feeding young adult male mice in a time-restrictive manner. Delay of meal time caused locomotive hyperactivity in a significant portion (42%) of subjects, while 6 h advance caused a torpor-like symptom during the late scotophase. Accordingly, daily rhythms of blood glucose and triglyceride were differentially affected by time-restrictive feeding regimen with concurrent metabolic alterations. Along with these physiological changes, time-restrictive feeding also influenced the circadian expression patterns of low density lipoprotein receptor (LDLR) as well as most LDLR regulatory factors. Strikingly, chronic advance of meal time induced insulin resistance, while chronic delay significantly elevated blood glucose levels. Taken together, our findings indicate that persistent shifts in usual meal time impact the diurnal rhythms of carbohydrate and lipid metabolisms in addition to HCA and BT, thereby posing critical implications for the health and diseases of shift workers. PMID:22952870

  6. Movement Sonification: Effects on Motor Learning beyond Rhythmic Adjustments.

    PubMed

    Effenberg, Alfred O; Fehse, Ursula; Schmitz, Gerd; Krueger, Bjoern; Mechling, Heinz

    2016-01-01

    motor skill (technique acquisition of indoor rowing). One group was treated with visual information and two groups with audiovisual information (sonification vs. natural sounds). For all three groups learning became evident and remained stable. Participants treated with additional movement sonification showed better performance compared to both other groups. Results indicate that movement sonification enhances motor learning of a complex gross motor skill-even exceeding usually expected acoustic rhythmic effects on motor learning.

  7. Movement Sonification: Effects on Motor Learning beyond Rhythmic Adjustments

    PubMed Central

    Effenberg, Alfred O.; Fehse, Ursula; Schmitz, Gerd; Krueger, Bjoern; Mechling, Heinz

    2016-01-01

    motor skill (technique acquisition of indoor rowing). One group was treated with visual information and two groups with audiovisual information (sonification vs. natural sounds). For all three groups learning became evident and remained stable. Participants treated with additional movement sonification showed better performance compared to both other groups. Results indicate that movement sonification enhances motor learning of a complex gross motor skill—even exceeding usually expected acoustic rhythmic effects on motor learning. PMID:27303255

  8. Kinematic analysis of basic rhythmic movements of hip-hop dance: motion characteristics common to expert dancers.

    PubMed

    Sato, Nahoko; Nunome, Hiroyuki; Ikegami, Yasuo

    2015-02-01

    In hip-hop dance contests, a procedure for evaluating performances has not been clearly defined, and objective criteria for evaluation are necessary. It is assumed that most hip-hop dance techniques have common motion characteristics by which judges determine the dancer's skill level. This study aimed to extract motion characteristics that may be linked to higher evaluations by judges. Ten expert and 12 nonexpert dancers performed basic rhythmic movements at a rate of 100 beats per minute. Their movements were captured using a motion capture system, and eight judges evaluated the performances. Four kinematic parameters, including the amplitude of the body motions and the phase delay, which indicates the phase difference between two joint angles, were calculated. The two groups showed no significant differences in terms of the amplitudes of the body motions. In contrast, the phase delay between the head motion and the other body parts' motions of expert dancers who received higher scores from the judges, which was approximately a quarter cycle, produced a loop-shaped motion of the head. It is suggested that this slight phase delay was related to the judges' evaluations and that these findings may help in constructing an objective evaluation system.

  9. The design of a device for hearer and feeler differentiation, part A. [speech modulated hearing device

    NASA Technical Reports Server (NTRS)

    Creecy, R.

    1974-01-01

    A speech modulated white noise device is reported that gives the rhythmic characteristics of a speech signal for intelligible reception by deaf persons. The signal is composed of random amplitudes and frequencies as modulated by the speech envelope characteristics of rhythm and stress. Time intensity parameters of speech are conveyed through the vibro-tactile sensation stimuli.

  10. p53-upregulated-modulator-of-apoptosis (PUMA) deficiency affects food intake but does not impact on body weight or glucose homeostasis in diet-induced obesity.

    PubMed Central

    Litwak, Sara A.; Loh, Kim; Stanley, William J.; Pappas, Evan G.; Wali, Jibran A.; Selck, Claudia; Strasser, Andreas; Thomas, Helen E.; Gurzov, Esteban N.

    2016-01-01

    BCL-2 proteins have been implicated in the control of glucose homeostasis and metabolism in different cell types. Thus, the aim of this study was to determine the role of the pro-apoptotic BH3-only protein, p53-upregulated-modulator-of-apoptosis (PUMA), in metabolic changes mediated by diet-induced obesity, using PUMA deficient mice. At 10 weeks of age, knockout and wild type mice either continued consuming a low fat chow diet (6% fat), or were fed with a high fat diet (23% fat) for 14–17 weeks. We measured body composition, glucose and insulin tolerance, insulin response in peripheral tissues, energy expenditure, oxygen consumption, and respiratory exchange ratio in vivo. All these parameters were indistinguishable between wild type and knockout mice on chow diet and were modified equally by diet-induced obesity. Interestingly, we observed decreased food intake and ambulatory capacity of PUMA knockout mice on high fat diet. This was associated with increased adipocyte size and fasted leptin concentration in the blood. Our findings suggest that although PUMA is dispensable for glucose homeostasis in lean and obese mice, it can affect leptin levels and food intake during obesity. PMID:27033313

  11. A treatment-planning comparison of three beam arrangement strategies for stereotactic body radiation therapy for centrally located lung tumors using volumetric-modulated arc therapy

    PubMed Central

    Ishii, Kentaro; Okada, Wataru; Ogino, Ryo; Kubo, Kazuki; Kishimoto, Shun; Nakahara, Ryuta; Kawamorita, Ryu; Ishii, Yoshie; Tada, Takuhito; Nakajima, Toshifumi

    2016-01-01

    The purpose of this study was to determine appropriate beam arrangement for volumetric-modulated arc therapy (VMAT)-based stereotactic body radiation therapy (SBRT) in the treatment of patients with centrally located lung tumors. Fifteen consecutive patients with centrally located lung tumors treated at our institution were enrolled. For each patient, three VMAT plans were generated using two coplanar partial arcs (CP VMAT), two non-coplanar partial arcs (NCP VMAT), and one coplanar full arc (Full VMAT). All plans were designed to deliver 70 Gy in 10 fractions. Target coverage and sparing of organs at risk (OARs) were compared across techniques. PTV coverage was almost identical for all approaches. The whole lung V10Gy was significantly lower with CP VMAT plans than with NCP VMAT plans, whereas no significant differences in the mean lung dose, V5Gy, V20Gy or V40Gy were observed. Full VMAT increased mean contralateral lung V5Gy by 12.57% and 9.15% when compared with NCP VMAT and CP VMAT, respectively. Although NCP VMAT plans best achieved the dose–volume constraints for mediastinal OARs, the absolute differences in dose were small when compared with CP VMAT. These results suggest that partial-arc VMAT may be preferable to minimize unnecessary exposure to the contralateral lung, and use of NCP VMAT should be considered when the dose–volume constraints are not achieved by CP VMAT. PMID:26951076

  12. p53-upregulated-modulator-of-apoptosis (PUMA) deficiency affects food intake but does not impact on body weight or glucose homeostasis in diet-induced obesity.

    PubMed

    Litwak, Sara A; Loh, Kim; Stanley, William J; Pappas, Evan G; Wali, Jibran A; Selck, Claudia; Strasser, Andreas; Thomas, Helen E; Gurzov, Esteban N

    2016-04-01

    BCL-2 proteins have been implicated in the control of glucose homeostasis and metabolism in different cell types. Thus, the aim of this study was to determine the role of the pro-apoptotic BH3-only protein, p53-upregulated-modulator-of-apoptosis (PUMA), in metabolic changes mediated by diet-induced obesity, using PUMA deficient mice. At 10 weeks of age, knockout and wild type mice either continued consuming a low fat chow diet (6% fat), or were fed with a high fat diet (23% fat) for 14-17 weeks. We measured body composition, glucose and insulin tolerance, insulin response in peripheral tissues, energy expenditure, oxygen consumption, and respiratory exchange ratio in vivo. All these parameters were indistinguishable between wild type and knockout mice on chow diet and were modified equally by diet-induced obesity. Interestingly, we observed decreased food intake and ambulatory capacity of PUMA knockout mice on high fat diet. This was associated with increased adipocyte size and fasted leptin concentration in the blood. Our findings suggest that although PUMA is dispensable for glucose homeostasis in lean and obese mice, it can affect leptin levels and food intake during obesity.

  13. The rhythmic, transverse medullary slice preparation in respiratory neurobiology: contributions and caveats.

    PubMed

    Funk, Gregory D; Greer, John J

    2013-04-01

    Our understanding of the sites and mechanisms underlying rhythmic breathing as well as the neuromodulatory control of respiratory rhythm, pattern, and respiratory motoneuron excitability during perinatal development has advanced significantly over the last 20 years. A major catalyst was the development in 1991 of the rhythmically-active medullary slice preparation, which provided precise mechanical and chemical control over the network as well as enhanced physical and optical access to key brainstem regions. Insights obtained in vitro have informed multiple mechanistic hypotheses. In vivo tests of these hypotheses, performed under conditions of reduced control and precision but more obvious physiological relevance, have clearly established the significance for respiratory neurobiology of the rhythmic slice preparation. We review the contributions of this preparation to current understanding/concepts in respiratory control, and outline the limitations of this approach in the context of studying rhythm and pattern generation, homeostatic control mechanisms and murine models of human genetic disorders that feature prominent breathing disturbances.

  14. Acoustic correlates of English rhythmic patterns for American versus Japanese speakers.

    PubMed

    Mori, Yoko; Hori, Tomoko; Erickson, Donna

    2014-01-01

    This study investigates acoustic correlates of English rhythmic patterns for 20 American English speakers (AS) and 42 Japanese learners of English (JS). The results indicate that for AS in an English sentence where monosyllabic content and function words alternate, the vowels in content words are over twice as long as those in function words, resulting in alternating long-short vowels. In contrast, the JS show no stress-related duration control and realize a similar rhythmic pattern mostly through recursive high-low fundamental frequency (F0). In a sentence with a sequence of content words in which 4 stressed syllables occur successively, the AS show recursion of strong-weak syllables by means of F0, intensity and first formant, whereas JS show inconsistent stress patterns. These results indicate that the AS apply different strategies for implementing rhythmic alternation depending on sentence stress patterns, and these strategies are different from those of JS.

  15. Rhythmicity of the intestinal microbiota is regulated by gender and the host circadian clock

    PubMed Central

    Liang, Xue; Bushman, Frederic D.; FitzGerald, Garret A.

    2015-01-01

    In mammals, multiple physiological, metabolic, and behavioral processes are subject to circadian rhythms, adapting to changing light in the environment. Here we analyzed circadian rhythms in the fecal microbiota of mice using deep sequencing, and found that the absolute amount of fecal bacteria and the abundance of Bacteroidetes exhibited circadian rhythmicity, which was more pronounced in female mice. Disruption of the host circadian clock by deletion of Bmal1, a gene encoding a core molecular clock component, abolished rhythmicity in the fecal microbiota composition in both genders. Bmal1 deletion also induced alterations in bacterial abundances in feces, with differential effects based on sex. Thus, although host behavior, such as time of feeding, is of recognized importance, here we show that sex interacts with the host circadian clock, and they collectively shape the circadian rhythmicity and composition of the fecal microbiota in mice. PMID:26240359

  16. Periodic Stresses in Gyroscopic Bodies, with Applications to Air Screws

    NASA Technical Reports Server (NTRS)

    Zahm, A F

    1918-01-01

    Report discusses periodic stresses in gyroscopic bodies with applications to air screws caused by particle mass. Report concludes that all modern air screws obey the laws found for plane groups of particles. In particular the two-bladers exert on the shaft a rhythmic gyroscopic torque; the multibladers a steady one; both easily calculable for any given conditions of motion and mass distribution.

  17. Studies of the phase gradient at the boundary of the phase diffusion equation, motivated by peculiar wave patterns of rhythmic contraction in the amoeboid movement of Physarum polycephalum

    NASA Astrophysics Data System (ADS)

    Iima, Makoto; Kori, Hiroshi; Nakagaki, Toshiyuki

    2017-04-01

    The boundary of a cell is the interface with its surroundings and plays a key role in controlling the cell movement adaptations to different environments. We propose a study of the boundary effects on the patterns and waves of the rhythmic contractions in plasmodia of Physarum polycephalum, a tractable model organism of the amoeboid type. Boundary effects are defined as the effects of both the boundary conditions and the boundary shape. The rhythmicity of contraction can be modulated by local stimulation of temperature, light and chemicals, and by local deformation of cell shape via mechanosensitive ion channels as well. First, we examined the effects of boundary cell shapes in the case of a special shape resembling a tadpole, while requiring that the natural frequency in the proximity of the boundary is slightly higher and uniform. The simulation model reproduced the approximate propagated wave, from the tail to the head, while the inward waves were observed only near the periphery of the head section of the tadpole-shape. A key finding was that the frequency of the rhythmic contractions depended on the local shape of cell boundary. This implies that the boundary conditions of the phase were not always homogeneous. To understand the dependency, we reduced the two-dimensional model into a one-dimensional continuum model with Neumann boundary conditions. Here, the boundary conditions reflect the frequency distribution at the boundary. We described the analytic solutions and calculated the relationship between the boundary conditions and the wave propagation for a one-dimensional model of the continuous oscillatory field and a discrete coupled oscillator system. The results obtained may not be limited to cell movement of Physarum, but may be applicable to the other physical systems since the analysis used a generic phase diffusion equation.

  18. Preclinical evidence supporting the clinical development of central pattern generator-modulating therapies for chronic spinal cord-injured patients

    PubMed Central

    2014-01-01

    Ambulation or walking is one of the main gaits of locomotion. In terrestrial animals, it may be defined as a series of rhythmic and bilaterally coordinated movement of the limbs which creates a forward movement of the body. This applies regardless of the number of limbs—from arthropods with six or more limbs to bipedal primates. These fundamental similarities among species may explain why comparable neural systems and cellular properties have been found, thus far, to control in similar ways locomotor rhythm generation in most animal models. The aim of this article is to provide a comprehensive review of the known structural and functional features associated with central nervous system (CNS) networks that are involved in the control of ambulation and other stereotyped motor patterns—specifically Central Pattern Generators (CPGs) that produce basic rhythmic patterned outputs for locomotion, micturition, ejaculation, and defecation. Although there is compelling evidence of their existence in humans, CPGs have been most studied in reduced models including in vitro isolated preparations, genetically-engineered mice and spinal cord-transected animals. Compared with other structures of the CNS, the spinal cord is generally considered as being well-preserved phylogenetically. As such, most animal models of spinal cord-injured (SCI) should be considered as valuable tools for the development of novel pharmacological strategies aimed at modulating spinal activity and restoring corresponding functions in chronic SCI patients. PMID:24910602

  19. Preclinical evidence supporting the clinical development of central pattern generator-modulating therapies for chronic spinal cord-injured patients.

    PubMed

    Guertin, Pierre A

    2014-01-01

    Ambulation or walking is one of the main gaits of locomotion. In terrestrial animals, it may be defined as a series of rhythmic and bilaterally coordinated movement of the limbs which creates a forward movement of the body. This applies regardless of the number of limbs-from arthropods with six or more limbs to bipedal primates. These fundamental similarities among species may explain why comparable neural systems and cellular properties have been found, thus far, to control in similar ways locomotor rhythm generation in most animal models. The aim of this article is to provide a comprehensive review of the known structural and functional features associated with central nervous system (CNS) networks that are involved in the control of ambulation and other stereotyped motor patterns-specifically Central Pattern Generators (CPGs) that produce basic rhythmic patterned outputs for locomotion, micturition, ejaculation, and defecation. Although there is compelling evidence of their existence in humans, CPGs have been most studied in reduced models including in vitro isolated preparations, genetically-engineered mice and spinal cord-transected animals. Compared with other structures of the CNS, the spinal cord is generally considered as being well-preserved phylogenetically. As such, most animal models of spinal cord-injured (SCI) should be considered as valuable tools for the development of novel pharmacological strategies aimed at modulating spinal activity and restoring corresponding functions in chronic SCI patients.

  20. The cholinergic system, circadian rhythmicity, and time memory.

    PubMed

    Hut, R A; Van der Zee, E A

    2011-08-10

    This review provides an overview of the interaction between the mammalian cholinergic system and circadian system, and its possible role in time memory. Several studies made clear that circadian (daily) fluctuations in acetylcholine (ACh) release, cholinergic enzyme activity and cholinergic receptor expression varies remarkably between species and even strains. Apparently, cholinergic features can be flexibly adjusted to the needs of a species or strain. Nevertheless, it can be generalized that circadian rhythmicity in the cholinergic system is characterized by high ACh release during the active phase of an individual. During the active phase, the activity of the ACh synthesizing enzyme Choline Acetyltransferase (ChAT) is enhanced, and the activity of the ACh degrading enzyme Acetylcholinesterase (AChE) is reduced. The number of free, unbound and thus available muscarinic acetylcholine receptors (mAChRs) is highest when ACh release is lowest. The cholinergic innervation of the suprachiasmatic nucleus (SCN), the hypothalamic circadian master clock, arises from the cholinergic forebrain and brain stem nuclei. The density of cholinergic fibers and terminals is modest as compared to other hypothalamic nuclei. This is the case for rat, hamster and mouse, three chronobiological model rodent species studied by us. A new finding is that the rat SCN contains some local cholinergic neurons. Hamster SCN contains less cholinergic neurons, whereas the mouse SCN is devoid of such cells. ACh has an excitatory effect on SCN cells (at least in vivo), and functions in close interaction with other neurotransmitters. Originally it was thought that ACh transferred retinal light information to the SCN. This turned out to be wrong. Thereafter, the phase shifting effects of ACh prompted researches to view ACh as an agent for nocturnal clock resetting. It is still not clear, however, what the function consequence is of SCN cholinergic neurotransmission. Here, we postulate the hypothesis

  1. SU-E-T-338: Dosimetric Study of Volumetric Modulated Arc Therapy (VMAT) and Intensity Modulated Radiation Therapy (IMRT) for Stereotactic Body Radiation Therapy (SBRT) in Early Stage Lung Cancer

    SciTech Connect

    Ahmad, I; Quinn, K; Seebach, A; Wang, H; Yah, R

    2015-06-15

    Purpose: This study evaluates the dosimetric differences using volumetric modulated arc therapy (VMAT) in patients previously treated with intensity modulated radiation therapy IMRT for stereotactic body radiotherapy (SBRT) in early stage lung cancer. Methods: We evaluated 9 consecutive medically inoperable lung cancer patients at the start of the SBRT program who were treated with IMRT from November 2010 to October 2011. These patients were treated using 6 MV energy. The 9 cases were then re-planned with VMAT performed with arc therapy using 6 MV flattening filter free (FFF) energy with the same organs at risk (OARS) constraints. Data collected for the treatment plans included target coverage, beam on time, dose to OARS and gamma pass rate. Results: Five patients were T1N0 and four patients were T2N0 with all tumors less than 5 cm. The average GTV was 13.02 cm3 (0.83–40.87) and average PTV was 44.65 cm3 (14.06–118.08). The IMRT plans had a mean of 7.2 angles (6–9) and 5.4 minutes (3.6–11.1) per plan. The VMAT plans had a mean of 2.8 arcs (2–3) and 4.0 minutes (2.2–6.0) per plan. VMAT had slightly more target coverage than IMRT with average increase in D95 of 2.68% (1.24–5.73) and D99 of 3.65% (0.88–8.77). VMAT produced lower doses to all OARs. The largest reductions were in maximum doses to the spinal cord with an average reduction of 24.1%, esophagus with an average reduction of 22.1%, and lung with an average reduction in the V20 of 16.3% The mean gamma pass rate was 99.8% (99.2–100) at 3 mm and 3% for VMAT with comparable values for IMRT. Conclusion: These findings suggest that using VMAT for SBRT in early stage lung cancer is superior to IMRT in terms of dose coverage, OAR dose and a lower treatment delivery time with a similar gamma pass rate.

  2. Learning and Discrimination of Audiovisual Events in Human Infants: The Hierarchical Relation between Intersensory Temporal Synchrony and Rhythmic Pattern Cues.

    ERIC Educational Resources Information Center

    Lewkowicz, David J.

    2003-01-01

    Three experiments examined 4- to 10-month-olds' perception of audio-visual (A-V) temporal synchrony cues in the presence or absence of rhythmic pattern cues. Results established that infants of all ages could discriminate between two different audio-visual rhythmic events. Only 10-month-olds detected a desynchronization of the auditory and visual…

  3. A Rhythmic Musical Intervention for Poor Readers: A Comparison of Efficacy with a Letter-Based Intervention

    ERIC Educational Resources Information Center

    Bhide, Adeetee; Power, Alan; Goswami, Usha

    2013-01-01

    There is growing evidence that children with reading difficulties show impaired auditory rhythm perception and impairments in musical beat perception tasks. Rhythmic musical interventions with poorer readers may thus improve rhythmic entrainment and consequently improve reading and phonological skills. Here we compare the effects of a musical…

  4. SU-E-T-812: Volumetric Modulated Arc Therapy-Total Body Irradiation (VMAT-TBI) V.s. Conventional Extended SSD-TBI (cTBI): A Dosimetric Comparisom

    SciTech Connect

    Ouyang, L; Folkerts, M; Lee, H; Ramirez, E; Timmerman, R; Abdulrahman, R; Jiang, S; Gu, X

    2015-06-15

    Purpose: To perform a dosimetric evaluation on a new developed volumetric modulated arc therapy based total body irradiation (VMAT-TBI). Methods: Three patients were CT scanned with an indexed rotatable body frame to get whole body CT images. Concatenated CT images were imported in Pinnacle treatment planning system and whole body and lung were contoured as PTV and organ at risk, respectively. Treatment plans were generated by matching multiple isocenter volumetric modulated arc (VMAT) fields of the upper body and multiple isocenter parallel-opposed fields of the lower body. For each plan, 1200 cGy in 8 fractions was prescribed to the whole body volume and the lung dose was constrained to a mean dose of 750 cGy. Such a two-level dose plan was achieved by inverse planning of the torso VMAT fields. For comparison, conventional standing TBI (cTBI) plans were generated on the same whole body CT images at an extended SSD (550cm).The shape of compensators and lung blocks are simulated using body segments and lung contours Compensation was calculated based on the patient CT images, in mimic of the standing TBI treatment. The whole body dose distribution of cTBI plans were calculated with a home-developed GPU Monte Carlo dose engine. Calculated cTBI dose distribution was prescribed to the mid-body point at umbilical level. Results: The VMAT-TBI treatment plans of three patients’ plans achieved 80.2%±5.0% coverage of the total body volume within ±10% of the prescription dose, while cTBI treatment plans achieved 72.2%±4.0% coverage of the total body volume. The averaged mean lung dose of all three patients is lower for VMAT-TBI (7.48 cGy) than for cTBI (8.96 cGy). Conclusion: The proposed patient comfort-oriented VMAT-TBI technique provides for a uniform dose distribution within the total body while reducing the dose to the lungs.

  5. Using an Artificial Neural Bypass to Restore Cortical Control of Rhythmic Movements in a Human with Quadriplegia

    NASA Astrophysics Data System (ADS)

    Sharma, Gaurav; Friedenberg, David A.; Annetta, Nicholas; Glenn, Bradley; Bockbrader, Marcie; Majstorovic, Connor; Domas, Stephanie; Mysiw, W. Jerry; Rezai, Ali; Bouton, Chad

    2016-09-01

    Neuroprosthetic technology has been used to restore cortical control of discrete (non-rhythmic) hand movements in a paralyzed person. However, cortical control of rhythmic movements which originate in the brain but are coordinated by Central Pattern Generator (CPG) neural networks in the spinal cord has not been demonstrated previously. Here we show a demonstration of an artificial neural bypass technology that decodes cortical activity and emulates spinal cord CPG function allowing volitional rhythmic hand movement. The technology uses a combination of signals recorded from the brain, machine-learning algorithms to decode the signals, a numerical model of CPG network, and a neuromuscular electrical stimulation system to evoke rhythmic movements. Using the neural bypass, a quadriplegic participant was able to initiate, sustain, and switch between rhythmic and discrete finger movements, using his thoughts alone. These results have implications in advancing neuroprosthetic technology to restore complex movements in people living with paralysis.

  6. Using an Artificial Neural Bypass to Restore Cortical Control of Rhythmic Movements in a Human with Quadriplegia

    PubMed Central

    Sharma, Gaurav; Friedenberg, David A.; Annetta, Nicholas; Glenn, Bradley; Bockbrader, Marcie; Majstorovic, Connor; Domas, Stephanie; Mysiw, W. Jerry; Rezai, Ali; Bouton, Chad

    2016-01-01

    Neuroprosthetic technology has been used to restore cortical control of discrete (non-rhythmic) hand movements in a paralyzed person. However, cortical control of rhythmic movements which originate in the brain but are coordinated by Central Pattern Generator (CPG) neural networks in the spinal cord has not been demonstrated previously. Here we show a demonstration of an artificial neural bypass technology that decodes cortical activity and emulates spinal cord CPG function allowing volitional rhythmic hand movement. The technology uses a combination of signals recorded from the brain, machine-learning algorithms to decode the signals, a numerical model of CPG network, and a neuromuscular electrical stimulation system to evoke rhythmic movements. Using the neural bypass, a quadriplegic participant was able to initiate, sustain, and switch between rhythmic and discrete finger movements, using his thoughts alone. These results have implications in advancing neuroprosthetic technology to restore complex movements in people living with paralysis. PMID:27658585

  7. Verification of Planning Target Volume Settings in Volumetric Modulated Arc Therapy for Stereotactic Body Radiation Therapy by Using In-Treatment 4-Dimensional Cone Beam Computed Tomography

    SciTech Connect

    Takahashi, Wataru; Yamashita, Hideomi; Kida, Satoshi; Masutani, Yoshitaka; Sakumi, Akira; Ohtomo, Kuni; Nakagawa, Keiichi; Haga, Akihiro

    2013-07-01

    Purpose: To evaluate setup error and tumor motion during beam delivery by using 4-dimensional cone beam computed tomography (4D CBCT) and to assess the adequacy of the planning target volume (PTV) margin for lung cancer patients undergoing volumetric modulated arc therapy for stereotactic body radiation therapy (VMAT-SBRT). Methods and Materials: Fifteen lung cancer patients treated by single-arc VMAT-SBRT were selected in this analysis. All patients were treated with an abdominal compressor. The gross tumor volumes were contoured on maximum inspiration and maximum expiration CT datasets from 4D CT respiratory sorting and merged into internal target volumes (ITVs). The PTV margin was isotropically taken as 5 mm. Registration was automatically performed using “pre-3D” CBCT. Treatment was performed with a D95 prescription of 50 Gy delivered in 4 fractions. The 4D tumor locations during beam delivery were determined using in-treatment 4D CBCT images acquired in each fraction. Then, the discrepancy between the actual tumor location and the ITV was evaluated in the lateral, vertical, and longitudinal directions. Results: Overall, 55 4D CBCT sets during VMAT-SBRT were successfully obtained. The amplitude of tumor motion was less than 10 mm in all directions. The average displacements between ITV and actual tumor location during treatment were 0.41 ± 0.93 mm, 0.15 ± 0.58 mm, and 0.60 ± 0.99 mm for the craniocaudal, left-right, and anteroposterior directions, respectively. The discrepancy in each phase did not exceed 5 mm in any direction. Conclusions: With in-treatment 4D CBCT, we confirmed the required PTV margins when the registration for moving target was performed using pre-3D CBCT. In-treatment 4D CBCT is a direct method for quantitatively assessing the intrafractional location of a moving target.

  8. BDNF and AMPA receptors in the cNTS modulate the hyperglycemic reflex after local carotid body NaCN stimulation.

    PubMed

    Cuéllar, R; Montero, S; Luquín, S; García-Estrada, J; Melnikov, V; Virgen-Ortiz, A; Lemus, M; Pineda-Lemus, M; de Álvarez-Buylla, E

    2017-02-03

    The application of sodium cyanide (NaCN) to the carotid body receptors (CBR) (CBR stimulation) induces rapid blood hyperglycemia and an increase in brain glucose retention. The commissural nucleus tractus solitarius (cNTS) is an essential relay nucleus in this hyperglycemic reflex; it receives glutamatergic afferents (that also release brain derived neurotrophic factor, BDNF) from the nodose-petrosal ganglia that relays CBR information. Previous work showed that AMPA in NTS blocks hyperglycemia and brain glucose retention after CBR stimulation. In contrast, BDNF, which attenuates glutamatergic AMPA currents in NTS, enhances these glycemic responses. Here we investigated the combined effects of BDNF and AMPA (and their antagonists) in NTS on the glycemic responses to CBR stimulation. Microinjections of BDNF plus AMPA into the cNTS before CBR stimulation in anesthetized rats, induced blood hyperglycemia and an increase in brain arteriovenous (a-v) of blood glucose concentration difference, which we infer is due to increased brain glucose retention. By contrast, the microinjection of the TrkB antagonist K252a plus AMPA abolished the glycemic responses to CBR stimulation similar to what is observed after AMPA pretreatments. In BDNF plus AMPA microinjections preceding CBR stimulation, the number of c-fos immunoreactive cNTS neurons increased. In contrast, in the rats microinjected with K252a plus AMPA in NTS, before CBR stimulation, c-fos expression in cNTS decreased. The expression of AMPA receptors GluR2/3 did not change in any of the studied groups. These results indicate that BDNF in cNTS plays a key role in the modulation of the hyperglycemic reflex initiated by CBR stimulation.

  9. A pilot study of intensity modulated radiation therapy with hypofractionated stereotactic body radiation therapy (SBRT) boost in the treatment of intermediate- to high-risk prostate cancer.

    PubMed

    Oermann, Eric K; Slack, Rebecca S; Hanscom, Heather N; Lei, Sue; Suy, Simeng; Park, Hyeon U; Kim, Joy S; Sherer, Benjamin A; Collins, Brian T; Satinsky, Andrew N; Harter, K William; Batipps, Gerald P; Constantinople, Nicholas L; Dejter, Stephen W; Maxted, William C; Regan, James B; Pahira, John J; McGeagh, Kevin G; Jha, Reena C; Dawson, Nancy A; Dritschilo, Anatoly; Lynch, John H; Collins, Sean P

    2010-10-01

    Clinical data suggest that large radiation fractions are biologically superior to smaller fraction sizes in prostate cancer radiotherapy. The CyberKnife is an appealing delivery system for hypofractionated radiosurgery due to its ability to deliver highly conformal radiation and to track and adjust for prostate motion in real-time. We report our early experience using the CyberKnife to deliver a hypofractionated stereotactic body radiation therapy (SBRT) boost to patients with intermediate- to high-risk prostate cancer. Twenty-four patients were treated with hypofractionated SBRT and supplemental external radiation therapy plus or minus androgen deprivation therapy (ADT). Patients were treated with SBRT to a dose of 19.5 Gy in 3 fractions followed by intensity modulated radiation therapy (IMRT) to a dose of 50.4 Gy in 28 fractions. Quality of life data were collected with American Urological Association (AUA) symptom score and Expanded Prostate Cancer Index Composite (EPIC) questionnaires before and after treatment. PSA responses were monitored; acute urinary and rectal toxicities were assessed using Common Toxicity Criteria (CTC) v3. All 24 patients completed the planned treatment with an average follow-up of 9.3 months. For patients who did not receive ADT, the median pre-treatment PSA was 10.6 ng/ml and decreased in all patients to a median of 1.5 ng/ml by 6 months post-treatment. Acute effects associated with treatment included Grade 2 urinary and gastrointestinal toxicity but no patient experienced acute Grade 3 or greater toxicity. AUA and EPIC scores returned to baseline by six months post-treatment. Hypofractionated SBRT combined with IMRT offers radiobiological benefits of a large fraction boost for dose escalation and is a well tolerated treatment option for men with intermediate- to high-risk prostate cancer. Early results are encouraging with biochemical response and acceptable toxicity. These data provide a basis for the design of a phase II clinical

  10. Modern Rhythmic Gymnastics. A Supplement to the K-12 Physical Education Curriculum Guide. Curriculum Support Series.

    ERIC Educational Resources Information Center

    Willoughby, Heather; Plumton, Diane

    This resource package has been designed to assist the instructor in using modern rhythmic gymnastics (MRG) to support the objectives cited in the "K-12 Physical Education Curriculum Guide," developed by the Manitoba Department of Education. MRG is based on scientific principles of movement, and makes use of small, hand-held apparatus…

  11. Gender Differences in Musical Aptitude, Rhythmic Ability and Motor Performance in Preschool Children

    ERIC Educational Resources Information Center

    Pollatou, Elisana; Karadimou, Konstantina; Gerodimos, Vasilios

    2005-01-01

    Most of the preschool curricula involve integrated movement activities that combine music, rhythm and locomotor skills. The purpose of the current study was to examine whether there are any differences between boys and girls at the age of five concerning their musical aptitude, rhythmic ability and performance in gross motor skills. Ninety-five…

  12. Bridging music and speech rhythm: rhythmic priming and audio-motor training affect speech perception.

    PubMed

    Cason, Nia; Astésano, Corine; Schön, Daniele

    2015-02-01

    Following findings that musical rhythmic priming enhances subsequent speech perception, we investigated whether rhythmic priming for spoken sentences can enhance phonological processing - the building blocks of speech - and whether audio-motor training enhances this effect. Participants heard a metrical prime followed by a sentence (with a matching/mismatching prosodic structure), for which they performed a phoneme detection task. Behavioural (RT) data was collected from two groups: one who received audio-motor training, and one who did not. We hypothesised that 1) phonological processing would be enhanced in matching conditions, and 2) audio-motor training with the musical rhythms would enhance this effect. Indeed, providing a matching rhythmic prime context resulted in faster phoneme detection, thus revealing a cross-domain effect of musical rhythm on phonological processing. In addition, our results indicate that rhythmic audio-motor training enhances this priming effect. These results have important implications for rhythm-based speech therapies, and suggest that metrical rhythm in music and speech may rely on shared temporal processing brain resources.

  13. Tap and Text: Using Poetry to Develop Rhythmic Proficiency in Percussive Dance Students

    ERIC Educational Resources Information Center

    Casey, Ryan P.

    2017-01-01

    As a longtime student and aficionado of both poetry and percussive dance, Ryan Casey presents ways in which poetry--both written and spoken word--can be used in a dance class to develop rhythmic proficiency in percussive dancers of varying ages and skill levels, and explains why he believes this practice is accessible and educational. Although the…

  14. Haptic feedback enhances rhythmic motor control by reducing variability, not improving convergence rate.

    PubMed

    Ankarali, M Mert; Tutkun Sen, H; De, Avik; Okamura, Allison M; Cowan, Noah J

    2014-03-01

    Stability and performance during rhythmic motor behaviors such as locomotion are critical for survival across taxa: falling down would bode well for neither cheetah nor gazelle. Little is known about how haptic feedback, particularly during discrete events such as the heel-strike event during walking, enhances rhythmic behavior. To determine the effect of haptic cues on rhythmic motor performance, we investigated a virtual paddle juggling behavior, analogous to bouncing a table tennis ball on a paddle. Here, we show that a force impulse to the hand at the moment of ball-paddle collision categorically improves performance over visual feedback alone, not by regulating the rate of convergence to steady state (e.g., via higher gain feedback or modifying the steady-state hand motion), but rather by reducing cycle-to-cycle variability. This suggests that the timing and state cues afforded by haptic feedback decrease the nervous system's uncertainty of the state of the ball to enable more accurate control but that the feedback gain itself is unaltered. This decrease in variability leads to a substantial increase in the mean first passage time, a measure of the long-term metastability of a stochastic dynamical system. Rhythmic tasks such as locomotion and juggling involve intermittent contact with the environment (i.e., hybrid transitions), and the timing of such transitions is generally easy to sense via haptic feedback. This timing information may improve metastability, equating to less frequent falls or other failures depending on the task.

  15. Accuracy and Variability of Isochronous Rhythmic Timing across Motor Systems in Stuttering versus Nonstuttering Individuals.

    ERIC Educational Resources Information Center

    Max, Ludo; Yudman, Elana M.

    2003-01-01

    This study with 10 adults who stutter and 10 nonstuttering controls completed speech, orofacial nonspeech, and finger isochronous rhythmic timing tasks to investigate the role of timing in stuttering. Findings extend growing evidence that stuttering individuals do not differ from nonstuttering individuals in the ability to generate temporal…

  16. Listening to Rhythmic Music Reduces Connectivity within the Basal Ganglia and the Reward System

    PubMed Central

    Brodal, Hans P.; Osnes, Berge; Specht, Karsten

    2017-01-01

    Music can trigger emotional responses in a more direct way than any other stimulus. In particular, music-evoked pleasure involves brain networks that are part of the reward system. Furthermore, rhythmic music stimulates the basal ganglia and may trigger involuntary movements to the beat. In the present study, we created a continuously playing rhythmic, dance floor-like composition where the ambient noise from the MR scanner was incorporated as an additional instrument of rhythm. By treating this continuous stimulation paradigm as a variant of resting-state, the data was analyzed with stochastic dynamic causal modeling (sDCM), which was used for exploring functional dependencies and interactions between core areas of auditory perception, rhythm processing, and reward processing. The sDCM model was a fully connected model with the following areas: auditory cortex, putamen/pallidum, and ventral striatum/nucleus accumbens of both hemispheres. The resulting estimated parameters were compared to ordinary resting-state data, without an additional continuous stimulation. Besides reduced connectivity within the basal ganglia, the results indicated a reduced functional connectivity of the reward system, namely the right ventral striatum/nucleus accumbens from and to the basal ganglia and auditory network while listening to rhythmic music. In addition, the right ventral striatum/nucleus accumbens demonstrated also a change in its hemodynamic parameter, reflecting an increased level of activation. These converging results may indicate that the dopaminergic reward system reduces its functional connectivity and relinquishing its constraints on other areas when we listen to rhythmic music.

  17. Outcome of Children with Hyperventilation-Induced High-Amplitude Rhythmic Slow Activity with Altered Awareness

    ERIC Educational Resources Information Center

    Barker, Alexander; Ng, Joanne; Rittey, Christopher D. C.; Kandler, Rosalind H.; Mordekar, Santosh R.

    2012-01-01

    Hyperventilation-induced high-amplitude rhythmic slow activity with altered awareness (HIHARS) is increasingly being identified in children and is thought to be an age-related non-epileptic electrographic phenomenon. We retrospectively investigated the clinical outcome in 15 children (six males, nine females) with HIHARS (mean age 7y, SD 1y 11mo;…

  18. Joyful Voices: Facilitating Language Growth through the Rhythmic Response to Chants.

    ERIC Educational Resources Information Center

    Buchoff, Rita

    1994-01-01

    Preschool and elementary school children can participate in pleasurable and worthwhile language experiences through the use of rhythmic group chants. Teachers can select contemporary poems, nursery rhymes, or have children make up their own chants. Provides examples of group chants and sources for chants, rhymes, and poems. (MDM)

  19. Neurobiological foundations of neurologic music therapy: rhythmic entrainment and the motor system

    PubMed Central

    Thaut, Michael H.; McIntosh, Gerald C.; Hoemberg, Volker

    2015-01-01

    Entrainment is defined by a temporal locking process in which one system’s motion or signal frequency entrains the frequency of another system. This process is a universal phenomenon that can be observed in physical (e.g., pendulum clocks) and biological systems (e.g., fire flies). However, entrainment can also be observed between human sensory and motor systems. The function of rhythmic entrainment in rehabilitative training and learning was established for the first time by Thaut and colleagues in several research studies in the early 1990s. It was shown that the inherent periodicity of auditory rhythmic patterns could entrain movement patterns in patients with movement disorders (see for a review: Thaut et al., 1999). Physiological, kinematic, and behavioral movement analysis showed very quickly that entrainment cues not only changed the timing of movement but also improved spatial and force parameters. Mathematical models have shown that anticipatory rhythmic templates as critical time constraints can result in the complete specification of the dynamics of a movement over the entire movement cycle, thereby optimizing motor planning and execution. Furthermore, temporal rhythmic entrainment has been successfully extended into applications in cognitive rehabilitation and speech and language rehabilitation, and thus become one of the major neurological mechanisms linking music and rhythm to brain rehabilitation. These findings provided a scientific basis for the development of neurologic music therapy. PMID:25774137

  20. Selective Auditory Attention in Adults: Effects of Rhythmic Structure of the Competing Language

    ERIC Educational Resources Information Center

    Reel, Leigh Ann; Hicks, Candace Bourland

    2012-01-01

    Purpose: The authors assessed adult selective auditory attention to determine effects of (a) differences between the vocal/speaking characteristics of different mixed-gender pairs of masking talkers and (b) the rhythmic structure of the language of the competing speech. Method: Reception thresholds for English sentences were measured for 50…

  1. Listening to Rhythmic Music Reduces Connectivity within the Basal Ganglia and the Reward System.

    PubMed

    Brodal, Hans P; Osnes, Berge; Specht, Karsten

    2017-01-01

    Music can trigger emotional responses in a more direct way than any other stimulus. In particular, music-evoked pleasure involves brain networks that are part of the reward system. Furthermore, rhythmic music stimulates the basal ganglia and may trigger involuntary movements to the beat. In the present study, we created a continuously playing rhythmic, dance floor-like composition where the ambient noise from the MR scanner was incorporated as an additional instrument of rhythm. By treating this continuous stimulation paradigm as a variant of resting-state, the data was analyzed with stochastic dynamic causal modeling (sDCM), which was used for exploring functional dependencies and interactions between core areas of auditory perception, rhythm processing, and reward processing. The sDCM model was a fully connected model with the following areas: auditory cortex, putamen/pallidum, and ventral striatum/nucleus accumbens of both hemispheres. The resulting estimated parameters were compared to ordinary resting-state data, without an additional continuous stimulation. Besides reduced connectivity within the basal ganglia, the results indicated a reduced functional connectivity of the reward system, namely the right ventral striatum/nucleus accumbens from and to the basal ganglia and auditory network while listening to rhythmic music. In addition, the right ventral striatum/nucleus accumbens demonstrated also a change in its hemodynamic parameter, reflecting an increased level of activation. These converging results may indicate that the dopaminergic reward system reduces its functional connectivity and relinquishing its constraints on other areas when we listen to rhythmic music.

  2. Preservation of Rhythmic Clocking in Cochlear Implant Users: A Study of Isochronous Versus Anisochronous Beat Detection

    PubMed Central

    Kim, Irene; Yang, Eunice; Donnelly, Patrick J.; Limb, Charles J.

    2010-01-01

    The capacity for internal rhythmic clocking involves a relationship between perceived auditory input and subsequent cognitive processing by which isochronous auditory stimuli induce a temporal beat expectancy in a listener. Although rhythm perception has previously been examined in cochlear implant (CI) users through various tasks based primarily on rhythm pattern identification, such tasks may not have been sufficiently nuanced to detect defects in internal rhythmic clocking, which requires temporal integration on a scale of milliseconds. The present study investigated the preservation of such rhythmic clocking in CI participants through a task requiring detection of isochronicity in the final beat of a four-beat series presented at different tempos. Our results show that CI users performed comparably to normal hearing (NH) participants in all isochronous rhythm detection tasks but that professionally trained musicians (MUS) significantly outperformed both NH and CI participants. These results suggest that CI users have intact rhythm perception even on a temporally demanding task that requires tight preservation of timing differences between a series of auditory events. Also, these results suggest that musical training might improve rhythmic clocking in CI users beyond normal hearing levels, which may be useful in light of the deficits in spectral processing commonly observed in CI users. PMID:21109551

  3. Differential maturation of rhythmic clock gene expression during early development in medaka (Oryzias latipes).

    PubMed

    Cuesta, Ines H; Lahiri, Kajori; Lopez-Olmeda, Jose Fernando; Loosli, Felix; Foulkes, Nicholas S; Vallone, Daniela

    2014-05-01

    One key challenge for the field of chronobiology is to identify how circadian clock function emerges during early embryonic development. Teleosts such as the zebrafish are ideal models for studying circadian clock ontogeny since the entire process of development occurs ex utero in an optically transparent chorion. Medaka (Oryzias latipes) represents another powerful fish model for exploring early clock function with, like the zebrafish, many tools available for detailed genetic analysis. However, to date there have been no reports documenting circadian clock gene expression during medaka development. Here we have characterized the expression of key clock genes in various developmental stages and in adult tissues of medaka. As previously reported for other fish, light dark cycles are required for the emergence of clock gene expression rhythms in this species. While rhythmic expression of per and cry genes is detected very early during development and seems to be light driven, rhythmic clock and bmal expression appears much later around hatching time. Furthermore, the maturation of clock function seems to correlate with the appearance of rhythmic expression of these positive elements of the clock feedback loop. By accelerating development through elevated temperatures or by artificially removing the chorion, we show an earlier onset of rhythmicity in clock and bmal expression. Thus, differential maturation of key elements of the medaka clock mechanism depends on the developmental stage and the presence of the chorion.

  4. Activity of the rat pontomedullary reticular neurons related to rhythmical jaw movements.

    PubMed

    Ohta, M; Sasamoto, K; Kishikawa, N; Kuraoka, N

    1999-11-01

    Electrical stimulation of the cerebral peduncle or oral mechanical or chemical stimulation induced rhythmical jaw movements (RJM) in the anesthetized rat. Extracellular recording was made from the pontomedullary reticular neurons in relation to RJM. The RJM-related activity was classified to a tonic, a transient and a phase-dependent rhythmical activities (116, 92 and 45 neurons, respectively). We found that the neurons showing the phase-dependent activities discharged exclusively or almost exclusively during RJM without responding to at least one of three kinds of RJM-inducing stimulation. Fourteen neurons were activated by all kinds of RJM-inducing stimulation and majority of them showed weak or no change in activity during RJM, although some showed the transient or the rhythmical activity during RJM. We propose that the phase-dependent rhythmical activity is necessary to generate RJM since any stimulation-induced RJM was reversibly blocked by microinjection of lidocaine or glutamate receptor blocking agents into the brainstem site concentrated by this type of neurons. No other type of activity was observed exclusively during RJM.

  5. Rhythmic Bimanual Coordination Is Impaired in Young Children with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Isenhower, Robert W.; Marsh, Kerry L.; Richardson, Michael J.; Helt, Molly; Schmidt, R. C.; Fein, Deborah

    2012-01-01

    Impairments in motor coordination are a common behavioral manifestation of autism spectrum disorder (ASD). We, therefore, used a drumming methodology to examine rhythmic bimanual coordination in children diagnosed with ASD (M = 47.3 months) and age-matched typically developing (TD) children (M = 42.6 months). Both groups were instructed to drum on…

  6. Novel object recognition of Djungarian hamsters depends on circadian time and rhythmic phenotype.

    PubMed

    Müller, Lisa; Fritzsche, Peter; Weinert, Dietmar

    2015-05-01

    what corresponds also to 1 h before and 2 h after their activity onset. In contrast, AR hamsters were not able to perform the NOR task at any time. The results show that the SCN modulate learning and memory in a circadian manner. Moreover, the loss of circadian rhythmicity results in cognitive impairments.

  7. Rhythmic bedding in prodeltaic deposits of the ancient Colorado River: Exploring genetic processes

    NASA Astrophysics Data System (ADS)

    Waresak, Sandra; Nalin, Ronald; Lucarelli, Andrea

    2016-04-01

    Prodeltaic deposits represent a valuable archive for the characterization of deltaic depositional systems, offering a distal, minimally reworked record of dominant processes active at the fluvial-marine interface. The Fish Creek Basin (CA, US) preserves a ~ 3-km thick, lower Pliocene, progradational deltaic succession formed when the ancestral Colorado River infiltrated a marine rift basin (the early Gulf of California). The unit in this succession interpreted as prodeltaic, corresponding to the upper Mud Hills Member of the Deguynos Formation, consists of ~ 300 m of muddy siltstones. A striking attribute of parts of this unit is the presence of rhythmic bedding, with consistently alternating silt- to fine sand-dominated and clay-dominated beds forming couplets with an average thickness of 12 cm. By performing a detailed sedimentological analysis of the rhythmites and investigating periodicities in bed thickness, our study aimed at reconstructing the mode of deposition of this enigmatic prodeltaic succession. We measured at high stratigraphic resolution 265 consecutive couplets, for a total thickness of 33 m. Individual beds have good lateral persistence of at least tens of meters and gradational to sharp, flat contacts. Observed sedimentary structures are concentrated on the coarser portion of the couplets and mostly consist of parallel and wavy lamination, with subordinate ripple cross-lamination and localized internal scours. Bioturbation appears low in intensity or absent. Most notably, grain size analysis performed with laser diffraction techniques on several couplets shows a consistent pattern of inverse grading transitioning to normal grading. The cumulative evidence of these sedimentological features indicates that deposition of the rhythmites was accomplished via hyperpycnal flows, each couplet most likely representing an individual event in a setting characterized by high overall depositional rates. We performed time series analysis on bed thickness of

  8. Ionic mechanism underlying recovery of rhythmic activity in adult isolated neurons

    PubMed Central

    Haedo, Rodolfo J.; Golowasch, Jorge

    2013-01-01

    Neurons exhibit long-term excitability changes necessary for maintaining proper cell and network activity in response to various inputs and perturbations. For instance, the adult crustacean pyloric network can spontaneously recover rhythmic activity after complete shutdown resulting from permanent removal of neuromodulatory inputs. Dissociated lobster stomatogastric ganglion (STG) neurons have been shown to spontaneously develop oscillatory activity via excitability changes. Rhythmic electrical stimulation can eliminate these oscillatory patterns in some cells. The ionic mechanisms underlying these changes are only partially understood. We used dissociated crab STG neurons to study the ionic mechanisms underlying spontaneous recovery of rhythmic activity and stimulation-induced activity changes. Similar to lobster neurons, rhythmic activity spontaneously develops in crab STG neurons. Rhythmic hyperpolarizing stimulation can eliminate, but more commonly accelerate the emergence of stable oscillatory activity depending on Ca++ influx at hyperpolarized voltages. Our main finding is that up-regulation of a Ca++-current and down-regulation of a high-threshold K+-current underlies the spontaneous homeostatic development of oscillatory activity. However, because of a non-linear dependence on stimulus frequency, hyperpolarization-induced oscillations appear to be inconsistent with a homeostatic regulation of activity. We find no difference in the activity patterns or the underlying ionic currents involved between neurons of the fast pyloric and the slow gastric mill networks during the first ten days in isolation. Dynamic-clamp experiments confirm that these conductance modifications can explain the observed activity changes. We conclude that spontaneous and stimulation-induced excitability changes in STG neurons can both result in intrinsic oscillatory activity via regulation of the same two conductances. PMID:16807346

  9. Rhesus Monkeys (Macaca mulatta) Detect Rhythmic Groups in Music, but Not the Beat

    PubMed Central

    Honing, Henkjan; Merchant, Hugo; Háden, Gábor P.; Prado, Luis; Bartolo, Ramón

    2012-01-01

    It was recently shown that rhythmic entrainment, long considered a human-specific mechanism, can be demonstrated in a selected group of bird species, and, somewhat surprisingly, not in more closely related species such as nonhuman primates. This observation supports the vocal learning hypothesis that suggests rhythmic entrainment to be a by-product of the vocal learning mechanisms that are shared by several bird and mammal species, including humans, but that are only weakly developed, or missing entirely, in nonhuman primates. To test this hypothesis we measured auditory event-related potentials (ERPs) in two rhesus monkeys (Macaca mulatta), probing a well-documented component in humans, the mismatch negativity (MMN) to study rhythmic expectation. We demonstrate for the first time in rhesus monkeys that, in response to infrequent deviants in pitch that were presented in a continuous sound stream using an oddball paradigm, a comparable ERP component can be detected with negative deflections in early latencies (Experiment 1). Subsequently we tested whether rhesus monkeys can detect gaps (omissions at random positions in the sound stream; Experiment 2) and, using more complex stimuli, also the beat (omissions at the first position of a musical unit, i.e. the ‘downbeat’; Experiment 3). In contrast to what has been shown in human adults and newborns (using identical stimuli and experimental paradigm), the results suggest that rhesus monkeys are not able to detect the beat in music. These findings are in support of the hypothesis that beat induction (the cognitive mechanism that supports the perception of a regular pulse from a varying rhythm) is species-specific and absent in nonhuman primates. In addition, the findings support the auditory timing dissociation hypothesis, with rhesus monkeys being sensitive to rhythmic grouping (detecting the start of a rhythmic group), but not to the induced beat (detecting a regularity from a varying rhythm). PMID:23251509

  10. Inhibition of midbrain-evoked tonic and rhythmic motor activity by cutaneous stimulation in decerebrate cats.

    PubMed

    Beyaert, C A; Haouzi, P; Marchal, F

    2003-03-01

    The effect of mechanical and electrical stimulation of cervical cutaneous afferents was analysed on both the centrally induced tonic and rhythmic activities in hindlimb antagonist muscle nerves of 16 decerebrate paralysed cats. Electrical stimulation of dorsal midbrain evoked in the nerve to the tibialis anterior muscle (TAn) either rhythmic discharges (n=14), associated with tonic discharges in ten cats, or only tonic discharges (n=4). Centrally induced activity in the ipsilateral nerve to gastrocnemius medialis (GMn) occurred in fewer cats (n=12) and displayed similar patterns as in TAn. Manual traction of the scruff of the neck reduced the TAn tonic and rhythmic discharges (n=6) by 73% (P<0.05) and 71% (P<0.05), respectively, and reduced only the tonic component of GMn discharges (by 41%, n=3). Electrical stimulation (impulses 0.1-0.5 ms, 50 Hz) of cervical nerves belonging to C5 or C6 dermatomes, the intensity (0.4-4 mA) of which induced minimal inhibition of both TAn and GMn discharges, reduced significantly the tonic component of TAn discharges (by 39%, n=4). At higher intensities of electrical cervical nerve stimulation (2-6 mA) inducing maximal inhibitory effect, both tonic and rhythmic activities in TAn and GMn were both significantly reduced by, respectively, 81% and 94% in TAn (n=7), and by 49% and 43% in GMn (n=7). Electrical cervical nerve stimulation consistently reduced the isolated tonic discharge in TAn by 66% (n=4, P<0.05) and in GMn by 23% (n=3) when present. Thus the tonic component was more sensitive to inhibition than the rhythmic component of hindlimb muscle nerve activity.

  11. Adipokines and adipocyte function in Clock mutant mice that retain melatonin rhythmicity.

    PubMed

    Kennaway, David J; Owens, Julie A; Voultsios, Athena; Wight, Nicole

    2012-02-01

    Clock(δ19)+MEL mutant mice, which retain melatonin rhythmicity, but lack peripheral tissue rhythmicity have impaired glucose tolerance, but reduced plasma free fatty acids, increased plasma adiponectin, and improved insulin sensitivity. Here, we report their response to a high-fat diet and adipocyte rhythmicity and function. The diet increased epigonadal fat weight similarly (twofold) in both wild-type and Clock(δ19)+MEL mice. The Clock(δ19) mutation abolished rhythmicity of Per2, Rev erbα and peroxisome proliferator-activated receptor-γ (Pparγ ) mRNA in epigonadal fat, but not Bmal1 mRNA, and reduced Rev erbα mRNA by 59 and 70% compared to the wild-type mice on the control and high-fat diets, respectively. The mutants had increased Adipoq mRNA expression in epigonadal fat (22%; P < 0.05) on a control diet, but showed no further change on a high-fat diet, and no change in Lep, Nampt or Retn mRNA on either diet. The Clock(δ19) mutation abolished rhythmicity of genes in epigonadal fat that contribute to plasma free fatty acids for mice on both diets, and increased Lipe mRNA expression in those on the high-fat diet. The persistent melatonin rhythm and reduced plasma free fatty acids in Clock(δ19)+MEL mutants may contribute to their enhanced insulin sensitivity, ameliorate the extent of impaired glucose homeostasis, and protect against the adverse effects of a high-fat diet.

  12. Origin of the slow afterhyperpolarization and slow rhythmic bursting in striatal cholinergic interneurons.

    PubMed

    Wilson, Charles J; Goldberg, Joshua A

    2006-01-01

    Striatal cholinergic interneurons recorded in slices exhibit three different firing patterns: rhythmic single spiking, irregular bursting, and rhythmic bursting. The rhythmic single-spiking pattern is governed mainly by a prominent brief afterhyperpolarization (mAHP) that follows single spikes. The mAHP arises from an apamin-sensitive calcium-dependent potassium current. A slower AHP (sAHP), also present in these neurons, becomes prominent during rhythmic bursting or driven firing. Although not apamin sensitive, the sAHP is caused by a calcium-dependent potassium conductance. It is not present after blockade of calcium current with cadmium or after calcium is removed from the media or when intracellular calcium is buffered with bis-(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid. It reverses at the potassium equilibrium potential. It can be generated by subthreshold depolarizations and persists after blockade of sodium currents by tetrodotoxin. It is slow, being maximal approximately 1 s after depolarization onset, and takes several seconds to decay. It requires >300-ms depolarizations to become maximally activated. Its voltage sensitivity is sigmoidal, with a half activation voltage of -40 mV. We conclude the sAHP is a high-affinity apamin-insensitive calcium-dependent potassium conductance, triggered by calcium currents partly activated at subthreshold levels. In combination with those calcium currents, it accounts for the slow oscillations seen in a subset of cholinergic interneurons exhibiting rhythmic bursting. In all cholinergic interneurons, it contributes to the slowdown or pause in firing that follows driven activity or prolonged subthreshold depolarizations and is therefore a candidate mechanism for the pause response observed in cholinergic neurons in vivo.

  13. Daily rhythmicity of the thermoregulatory responses of locally adapted Brazilian sheep in a semiarid environment

    NASA Astrophysics Data System (ADS)

    da Silva, Wilma Emanuela; Leite, Jacinara Hody Gurgel Morais; de Sousa, José Ernandes Rufino; Costa, Wirton Peixoto; da Silva, Wallace Sostene Tavares; Guilhermino, Magda Maria; Asensio, Luis Alberto Bermejo; Façanha, Débora Andréa Evangelista

    2017-01-01

    The goal of this study was to evaluate the daily rhythmicity of the thermoregulatory responses of Morada Nova ewes that were raised in a semiarid environment. The experiment was conducted during the dry season. Data were collected from 5:00 a.m. to 4:00 a.m.. Samples were taken over the course of 8 days, with a 1-week interval between sampling periods. During each day that the data were collected, animals were measured once an hour for 24 h in an area directly exposed to solar radiation. The environment was characterized by measuring the following variables: air temperature (TA), relative humidity (RH), Black Globe Humidity Index (BGHI), radiant heat load (RHL), and wind speed (WS). Physiological variables that were measured included rectal temperature (RT, °C), respiratory rate (RR, breaths/min), surface temperature (ST, °C), and sweating rate (SR, g m2 h-1). We observed that RT, RR, and ST increased as environmental conditions became more stressful. Specifically, environmental conditions became more stressful as RHL, air temperature, and BGHI increased, while RH decreased. All physiological variables of the animals were strongly affected by the time of the day: environmental variables changed drastically between nighttime and noon. Physiological parameters increased sharply from the morning (7:00 a.m.-10:00 a.m.) until noon (11:00 a.m.-2:00 p.m.), except for sweating rate. After noon, these variables began to drop until nighttime (11:00 p.m.-6:00 am), and values of the main physiological indexes were stable during this period. The Morada Nova breed exhibited daily cyclic variations in thermoregulatory responses. Evaporative heat loss mechanisms were triggered during the most stressful times of the day. The first mechanism that animals used was panting, which was an immediate response to environmental heat stress. Cutaneous evaporation had a slower response mechanism to environmental heat stress. Homeothermy conditions were restored to the animals at

  14. Coordination and modulation of locomotion pattern generators in Drosophila larvae: effects of altered biogenic amine levels by the tyramine beta hydroxlyase mutation.

    PubMed

    Fox, Lyle E; Soll, David R; Wu, Chun-Fang

    2006-02-01

    Forward locomotion of Drosophila melanogaster larvae is composed of rhythmic waves of contractions that are thought to be produced by segmentally organized central pattern generators. We present a systematic description of spike activity patterns during locomotive contraction waves in semi-intact wild-type and mutant larval preparations. We have shown previously that Tbetah(nM18) mutants, with altered levels of octopamine and tyramine, have a locomotion deficit. By recording en passant from the segmental nerves, we investigated the coordination of the neuronal activity driving contraction waves of the abdominal body-wall muscles. Rhythmic bursts of activity that occurred concurrently with locomotive waves were frequently observed in wild-type larvae but were rarely seen in Tbetah(nM18) mutants. These centrally generated patterned activities were eliminated in the distal stumps of both wild-type and Tbetah(nM18) larvae after severing the segmental nerve from the CNS. Patterned activities persisted in the proximal stumps deprived of sensory feedback from the periphery. Simultaneous recordings demonstrated a delay in the bursting activity between different segments, with greater delay for segments that were farther apart. In contrast, bilateral recordings within a single segment revealed a well synchronized activity pattern in nerves innervating each hemisegment in both wild-type and Tbetah(nM18) larvae. Significantly, rhythmic patterns of bursts and waves could be evoked in Tbetah(nM18) mutants by head or tail stimulation despite their highly irregular spontaneous activities. These observations suggest a role of the biogenic amines in the initiation and modulation of motor pattern generation. The technique presented here can be readily extended to examine the locomotion motor program of other mutants.

  15. Rhythmic auditory stimulation using a portable smart device: short-term effects on gait in chronic hemiplegic stroke patients

    PubMed Central

    Ko, Byung-Woo; Lee, Hwi-Young; Song, Won-Kyung

    2016-01-01

    [Purpose] The effects of various rhythmic auditory stimulation tempos on stroke gait pattern changes when training patients with a smartphone-based rhythmic auditory stimulation application were investigated. [Subjects and Methods] Fifteen patients with chronic stroke were included. Cadence during comfortable walking was measured (baseline). After the baseline findings were recorded, rhythmic auditory stimulation with five different tempos (i.e., −10%, −5%, 0%, +5%, and +10% change from baseline) was randomly applied. Finally, comfortable walking without rhythmic auditory stimulation was initiated to evaluate gait pattern changes. [Results] As the tempo increased, the spatiotemporal gait parameters of the stroke patients changed significantly. Gait speed, cadence, and gait cycle duration showed the greatest improvement in the +10% rhythmic auditory stimulation condition compared to baseline. After gait training with rhythmic auditory stimulation, gait speed, cadence, stride length, gait cycle duration, and step length of the affected and unaffected sides improved significantly compared to baseline. [Conclusion] Significant changes in the gait pattern of stroke patients were noted for various tempos after training with rhythmic auditory stimulation. These findings could be used to customize rehabilitative gait training for patients who experience stroke with hemiplegia. PMID:27313366

  16. Rhythmic Working Memory Activation in the Human Hippocampus.

    PubMed

    Leszczyński, Marcin; Fell, Juergen; Axmacher, Nikolai

    2015-11-10

    Working memory (WM) maintenance is assumed to rely on a single sustained process throughout the entire maintenance period. This assumption, although fundamental, has never been tested. We used intracranial electroencephalography (EEG) recordings from the human hippocampus in two independent experiments to investigate the neural dynamics underlying WM maintenance. We observed periodic fluctuations between two different oscillatory regimes: Periods of "memory activation" were reflected by load-dependent alpha power reductions and lower levels of cross-frequency coupling (CFC). They occurred interleaved with periods characterized by load-independent high levels of alpha power and CFC. During memory activation periods, a relevant CFC parameter (load-dependent changes of the peak modulated frequency) correlated with individual WM capacity. Fluctuations between these two periods predicted successful performance and were locked to the phase of endogenous delta oscillations. These results show that hippocampal maintenance is a dynamic rather than constant process and depends critically on a hierarchy of oscillations.

  17. Volumetric-modulated arc stereotactic body radiotherapy for prostate cancer: dosimetric impact of an increased near-maximum target dose and of a rectal spacer

    PubMed Central

    Naccarato, Stefania; Stavrev, Pavel; Stavreva, Nadejda; Fersino, Sergio; Giaj Levra, Niccolò; Mazzola, Rosario; Mancosu, Pietro; Scorsetti, Marta; Alongi, Filippo

    2015-01-01

    Objective: In volumetric-modulated arc therapy (VMAT) prostate stereotactic body radiotherapy (SBRT), dose coverage of the planning target volume (PTV) becomes challenging when the sparing of rectum, bladder and urethra is strictly pursued. Our current 35-Gy-in-five-fraction plans only assure 33.2 Gy to ≥95% PTV (V33.2PTV ≥ 95%). Looking for an improved V33.2PTV, increased near-maximum target dose (D2%) and prostate–rectum spacer insertion were tested. Methods: For 11 patients, two VMAT plans, with D2% ≤ 37.5 Gy (Hom) or D2% ≤ 40.2 Gy (Het), on each of two CT studies, before or after spacer insertion, were computed. All plans assured V33.2PTV ≥95%, and <1 cm3 of rectum, bladder and urethra receiving ≥35 Gy. By hypothesis testing, several dose–volume metrics for target coverage and rectal sparing were compared across the four groups of plans. The impact of spacer insertion on the fractions of rectum receiving more than 18, 28 and 32 Gy (VXr) was further tested by linear correlation analysis. Results: By hypothesis testing, the increased D2% was associated with improvements in target coverage, whereas spacer insertion was associated with improvements in both target coverage and rectal VXr. By linear correlation analysis, spacer insertion was related to the reductions in rectal VXr for X ≥ 28 Gy. Conclusion: A slightly increased D2% or the use of spacer insertion was each able to improve V33.2PTV. Their combined use assured V33.2PTV ≥ 98% to all our patients. Spacer insertion was further causative for improvements in rectal sparing. Advances in knowledge: For VMAT plans in prostate SBRT, the distinct dosimetric usefulness of increased D2% and of the use of spacer insertion were validated in terms of target coverage and rectal sparing. PMID:26235142

  18. Dosimetric evaluation of four-dimensional dose distributions of CyberKnife and volumetric-modulated arc radiotherapy in stereotactic body lung radiotherapy.

    PubMed

    Chan, Mark K H; Kwong, Dora L W; Law, Gilbert M L; Tam, Eric; Tong, Anthony; Lee, Venus; Ng, Sherry C Y

    2013-07-08

    Advanced image-guided stereotatic body lung radiotherapy techniques using volumetric-modulated arc radiotherapy (VMAT) with four-dimensional cone-beam computed tomography (4D CBCT) and CyberKnife with real-time target tracking have been clinically implemented by different authors. However, dosimetric comparisons between these techniques are lacking. In this study, 4D CT scans of 14 patients were used to create VMAT and CyberKnife treatment plans using 4D dose calculations. The GTV and the organs at risk (OARs) were defined on the end-exhale images for CyberKnife planning and were then deformed to the midventilation images (MidV) for VMAT optimization. Direct 4D Monte Carlo dose optimizations were performed for CyberKnife (4D(CK)). Four-dimensional dose calculations were also applied to VMAT plans to generate the 4D dose distributions (4D(VMAT)) on the exhale images for direct comparisons with the 4D(CK) plans. 4D(CK) and 4D(VMAT) showed comparable target conformity (1.31 ± 0.13 vs. 1.39 ± 0.24, p = 0.05). GTV mean doses were significantly higher with 4D(CK). Statistical differences of dose volume metrics were not observed in the majority of OARs studied, except for esophagus, with 4D(VMAT) yielding marginally higher D1% than 4D(CK). The normal tissue volumes receiving 80%, 50%, and 30% of the prescription dose (V80%, V50%, and V30%) were higher with 4D(VMAT), whereas 4D(CK) yielded slightly higher V10% in posterior lesions than 4D(VMAT). VMAT resulted in much less monitor units and therefore greater delivery efficiency than CyberKnife. In general, it was possible to produce dosimetrically acceptable plans with both techniques. The selection of treatment modality should consider the dosimetric results as well as the patient's tolerance of the treatment process specific to the SBRT technique.

  19. Neuromodulation to the Rescue: Compensation of Temperature-Induced Breakdown of Rhythmic Motor Patterns via Extrinsic Neuromodulatory Input.

    PubMed

    Städele, Carola; Heigele, Stefanie; Stein, Wolfgang

    2015-01-01

    Stable rhythmic neural activity depends on the well-coordinated interplay of synaptic and cell-intrinsic conductances. Since all biophysical processes are temperature dependent, this interplay is challenged during temperature fluctuations. How the nervous system remains functional during temperature perturbations remains mostly unknown. We present a hitherto unknown mechanism of how temperature-induced changes in neural networks are compensated by changing their neuromodulatory state: activation of neuromodulatory pathways establishes a dynamic coregulation of synaptic and intrinsic conductances with opposing effects on neuronal activity when temperature changes, hence rescuing neuronal activity. Using the well-studied gastric mill pattern generator of the crab, we show that modest temperature increase can abolish rhythmic activity in isolated neural circuits due to increased leak currents in rhythm-generating neurons. Dynamic clamp-mediated addition of leak currents was sufficient to stop neuronal oscillations at low temperatures, and subtraction of additional leak currents at elevated temperatures was sufficient to rescue the rhythm. Despite the apparent sensitivity of the isolated nervous system to temperature fluctuations, the rhythm could be stabilized by activating extrinsic neuromodulatory inputs from descending projection neurons, a strategy that we indeed found to be implemented in intact animals. In the isolated nervous system, temperature compensation was achieved by stronger extrinsic neuromodulatory input from projection neurons or by augmenting projection neuron influence via bath application of the peptide cotransmitter Cancer borealis tachykinin-related peptide Ia (CabTRP Ia). CabTRP Ia activates the modulator-induced current IMI (a nonlinear voltage-gated inward current) that effectively acted as a negative leak current and counterbalanced the temperature-induced leak to rescue neuronal oscillations. Computational modelling revealed the ability of

  20. Neuromodulation to the Rescue: Compensation of Temperature-Induced Breakdown of Rhythmic Motor Patterns via Extrinsic Neuromodulatory Input

    PubMed Central

    Städele, Carola; Heigele, Stefanie; Stein, Wolfgang

    2015-01-01

    Stable rhythmic neural activity depends on the well-coordinated interplay of synaptic and cell-intrinsic conductances. Since all biophysical processes are temperature dependent, this interplay is challenged during temperature fluctuations. How the nervous system remains functional during temperature perturbations remains mostly unknown. We present a hitherto unknown mechanism of how temperature-induced changes in neural networks are compensated by changing their neuromodulatory state: activation of neuromodulatory pathways establishes a dynamic coregulation of synaptic and intrinsic conductances with opposing effects on neuronal activity when temperature changes, hence rescuing neuronal activity. Using the well-studied gastric mill pattern generator of the crab, we show that modest temperature increase can abolish rhythmic activity in isolated neural circuits due to increased leak currents in rhythm-generating neurons. Dynamic clamp-mediated addition of leak currents was sufficient to stop neuronal oscillations at low temperatures, and subtraction of additional leak currents at elevated temperatures was sufficient to rescue the rhythm. Despite the apparent sensitivity of the isolated nervous system to temperature fluctuations, the rhythm could be stabilized by activating extrinsic neuromodulatory inputs from descending projection neurons, a strategy that we indeed found to be implemented in intact animals. In the isolated nervous system, temperature compensation was achieved by stronger extrinsic neuromodulatory input from projection neurons or by augmenting projection neuron influence via bath application of the peptide cotransmitter Cancer borealis tachykinin-related peptide Ia (CabTRP Ia). CabTRP Ia activates the modulator-induced current IMI (a nonlinear voltage-gated inward current) that effectively acted as a negative leak current and counterbalanced the temperature-induced leak to rescue neuronal oscillations. Computational modelling revealed the ability of

  1. Alterations in the rheological flow profile in conduit femoral artery during rhythmic thigh muscle contractions in humans.

    PubMed

    Osada, Takuya; Rådegran, Göran

    2005-02-01

    The present study examined the rheological blood velocity profile in the conduit femoral artery during rhythmic muscle contractions at different muscle forces. Eight healthy volunteers performed one-legged, dynamic knee-extensor exercise at work rates of 5, 10, 20, 30, and 40 W at 60 contractions per minute. The time and space-averaged, amplitude-weighted mean (V(mean)) and maximum (V(max)) blood flow velocities in the common femoral artery were measured during the cardiosystolic phase (CSP) and cardiodiastolic phase (CDP) by the Doppler ultrasound technique. The V(max)/V(mean) ratio was used as a flow profile index, in which a ratio of approximately 1 indicates a "flat velocity flow profile" and a ratio significantly >1 indicates a "parabolic velocity flow profile." At rest, the V(max)/V(mean) ratio was approximately 1.3 and approximately 1.8 during the CSP and CDP, respectively. The V(max)/V(mean) ratio was higher (p < 0.01) during the CDP than during the CSP, both at rest and at all work rates. The V(max)/V(mean) ratio during the CSP was higher (p < 0.01) at 30 and 40 W compared to at rest. The V(max)/V(mean) ratio during the CDP was lower (p < 0.05) at 5 and 10 W compared to at rest. There was a positive linear correlation between blood flow and incremental work rates during both the CSP and CDP, respectively. Thus under resting conditions, the findings indicate a "steeper" parabolic velocity profile during the CDP than during the CSP. The velocity profile during the CDP furthermore shifts to being less "steep" during rhythmic muscle contractions at lower intensities, but to being reelevated and normalized as at rest during higher intensities. The "steepness" of the parabolic velocity profile observed during the CSP at rest increased during muscle contraction at higher intensities. In conclusion, the blood velocity in the common femoral artery is parabolic both at rest and during exercise for both the CSP and CDP, indicating the persistence of laminar flow. The

  2. Properties of rhythmic activity generated by the isolated spinal cord of the neonatal mouse.

    PubMed

    Whelan, P; Bonnot, A; O'Donovan, M J

    2000-12-01

    We examined the ability of the isolated lumbosacral spinal cord of the neonatal mouse (P0-7) to generate rhythmic motor activity under several different conditions. In the absence of electrical or pharmacological stimulation, we recorded several patterns of spontaneous ventral root depolarization and discharge. Spontaneous, alternating discharge between contralateral ventral roots could occur two to three times over a 10-min interval. We also observed other patterns, including left-right synchrony and rhythmic activity restricted to one side of the cord. Trains of stimuli delivered to the lumbar/coccygeal dorsal roots or the sural nerve reliably evoked episodes of rhythmic activity. During these evoked episodes, rhythmic ventral root discharges could occur on one side of the cord or could alternate from side to side. Bath application of a combination of N-methyl-D,L-aspartate (NMA), serotonin, and dopamine produced rhythmic activity that could last for several hours. Under these conditions, the discharge recorded from the left and right L(1)-L(3) ventral roots alternated. In the L(4)-L(5) segments, the discharge had two peaks in each cycle, coincident with discharge of the ipsilateral and contralateral L(1)-L(3) roots. The L(6) ventral root discharge alternated with that recorded from the ipsilateral L(1)-L(3) roots. We established that the drug-induced rhythm was locomotor-like by recording an alternating pattern of discharge between ipsilateral flexor and extensor hindlimb muscle nerves. In addition, by recording simultaneously from ventral roots and muscle nerves, we established that ankle flexor discharge was in phase with ipsilateral L(1)/L(2) ventral root discharge, while extensor discharge was in phase with ipsilateral L(6) ventral root discharge. Rhythmic patterns of ventral root discharge were preserved following mid-sagittal section of the spinal cord, demonstrating that reciprocal inhibitory connections between the left and right sides of the cord are

  3. Aging diurnal rhythms and chronic stress: Distinct alteration of diurnal rhythmicity of salivary alpha-amylase and cortisol.

    PubMed

    Strahler, Jana; Berndt, Christiane; Kirschbaum, Clemens; Rohleder, Nicolas

    2010-05-01

    The present study assessed diurnal profiles of salivary alpha-amylase (sAA), proposed as a marker of autonomic activity, and salivary cortisol in competitive ballroom dancers as well as age- and sex-matched controls to investigate age-related changes of basal activity and potential chronic psychosocial stress-related alterations. According to the Allostatic Load (AL) hypothesis of a cumulative wear and tear of the body we expected to see physiological accumulation of the effects of stress and age especially pronounced in older dancers. Dancers and controls collected five saliva samples throughout the day. Daily overall output of sAA was elevated in older adults while there was no effect of age on mean cortisol levels. Alterations of diurnal rhythms were only seen in younger male dancers showing a flattened diurnal profile of sAA and younger dancers and female older dancers showing a blunted diurnal rhythmicity of cortisol. Furthermore, we found a negative correlation between summary indices of basal sAA and the amount of physical activity. In conclusion, higher overall output of sAA in older adults is in line with the phenomenon of a sympathetic "drive" with increasing age. Furthermore, a lower output of sAA in people who are more physical active is in line with the hypothesis of an exercise-induced decrease of sympathetic activity. Overall, our study does not support the AL hypothesis, but rather highlights the importance of regular physical activity and social environment in promoting health.

  4. Rhythmic Oxygen Levels Reset Circadian Clocks through HIF1α.

    PubMed

    Adamovich, Yaarit; Ladeuix, Benjamin; Golik, Marina; Koeners, Maarten P; Asher, Gad

    2017-01-10

    The mammalian circadian system consists of a master clock in the brain that synchronizes subsidiary oscillators in peripheral tissues. The master clock maintains phase coherence in peripheral cells through systemic cues such as feeding-fasting and temperature cycles. Here, we examined the role of oxygen as a resetting cue for circadian clocks. We continuously measured oxygen levels in living animals and detected daily rhythms in tissue oxygenation. Oxygen cycles, within the physiological range, were sufficient to synchronize cellular clocks in a HIF1α-dependent manner. Furthermore, several clock genes responded to changes in oxygen levels through HIF1α. Finally, we found that a moderate reduction in oxygen levels for a short period accelerates the adaptation of wild-type but not of HIF1α-deficient mice to the new time in a jet lag protocol. We conclude that oxygen, via HIF1α activation, is a resetting cue for circadian clocks and propose oxygen modulation as therapy for jet lag.

  5. Firefighting Module

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Aviation Power Supply's mobile firefighting module called Firefly II is mounted on a trailer pulled by a pickup truck. Trailer unit has two three- inch water cannons, and the pickup carries a six inch cannon. Completely self contained, module pumps 3,000 gallons of water a minute from hydrants or open bodies of water. Stream can go as far as 400 feet or can be employed in a high-loft mode to reach the tops of tall refinery towers. Compact Firefly II weighs only 2,500 pounds when fully fueled. Key component is a specially designed two stage pump. Power for the pump is generated by a gas turbine engine. Module also includes an electronic/pump controller, multiple hose connections, up to 1,500 feet of hose and fuel for four hours operation. Firefly trailer can be backed onto specially-built large fireboat.

  6. Firefighting Module

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Aviation Power Supply's mobile firefighting module called Firefly II is mounted on a trailer pulled by a pickup truck. Trailer unit has two three- inch water cannons, and the pickup carries a six inch cannon. Completely self contained, module pumps 3,000 gallons of water a minute from hydrants or open bodies of water. Stream can go as far as 400 feet or can be employed in a high-loft mode to reach the tops of tall refinery towers. Compact Firefly II weighs only 2,500 pounds when fully fueled. Key component is a specially designed two stage pump. Power for the pump is generated by a gas turbine engine. Module also includes an electronic/pump controller, multiple hose connections, up to 1,500 feet of hose and fuel for four hours operation. Firefly trailer can be backed onto specially-built large fireboat.

  7. Short- and long-term rhythmic interventions: perspectives for language rehabilitation.

    PubMed

    Schön, Daniele; Tillmann, Barbara

    2015-03-01

    This paper brings together different perspectives on the investigation and understanding of temporal processing and temporal expectations. We aim to bridge different temporal deficit hypotheses in dyslexia, dysphasia, or deafness in a larger framework, taking into account multiple nested temporal scales. We present data testing the hypothesis that temporal attention can be influenced by external rhythmic auditory stimulation (i.e., musical rhythm) and benefits subsequent language processing, including syntax processing and speech production. We also present data testing the hypothesis that phonological awareness can be influenced by several months of musical training and, more particularly, rhythmic training, which in turn improves reading skills. Together, our data support the hypothesis of a causal role of rhythm-based processing for language processing and acquisition. These results open new avenues for music-based remediation of language and hearing impairment.

  8. Rhythmic tongue movements during sleep: a peculiar parasomnia in Costello syndrome.

    PubMed

    Della Marca, Giacomo; Rubino, Marco; Vollono, Catello; Vasta, Isabella; Scarano, Emanuele; Mariotti, Paolo; Cianfoni, Alessandro; Mennuni, Gioacchino Francesco; Tonali, Pietro; Zampino, Giuseppe

    2006-04-01

    We describe a peculiar parasomnia observed in four Costello infants, characterized by periodic rhythmic movements of the tongue. Ten Costello patients (4 male; age range 9 months to 29 years) underwent 1 full-night laboratory-based video polysomnography. The four youngest patients (2 male and 2 female; age range 9-31 months) presented during sleep repeated stereotyped movements of the tongue, producing a sucking-like or licking-like movement, mostly during non-rapid eye movement (NREM) sleep. Rhythmic tongue movements in Costello syndrome show the features of an NREM sleep parasomnia. Tongue movements during sleep probably originate from brainstem structures and could be facilitated by an impaired control of the oropharyngeal and tongue muscles.

  9. Modelling the Effects of Electrical Coupling between Unmyelinated Axons of Brainstem Neurons Controlling Rhythmic Activity

    PubMed Central

    Hull, Michael J.; Soffe, Stephen R.; Willshaw, David J.; Roberts, Alan

    2015-01-01

    Gap junctions between fine unmyelinated axons can electrically couple groups of brain neurons to synchronise firing and contribute to rhythmic activity. To explore the distribution and significance of electrical coupling, we modelled a well analysed, small population of brainstem neurons which drive swimming in young frog tadpoles. A passive network of 30 multicompartmental neurons with unmyelinated axons was used to infer that: axon-axon gap junctions close to the soma gave the best match to experimentally measured coupling coefficients; axon diameter had a strong influence on coupling; most neurons were coupled indirectly via the axons of other neurons. When active channels were added, gap junctions could make action potential propagation along the thin axons unreliable. Increased sodium and decreased potassium channel densities in the initial axon segment improved action potential propagation. Modelling suggested that the single spike firing to step current injection observed in whole-cell recordings is not a cellular property but a dynamic consequence of shunting resulting from electrical coupling. Without electrical coupling, firing of the population during depolarising current was unsynchronised; with coupling, the population showed synchronous recruitment and rhythmic firing. When activated instead by increasing levels of modelled sensory pathway input, the population without electrical coupling was recruited incrementally to unpatterned activity. However, when coupled, the population was recruited all-or-none at threshold into a rhythmic swimming pattern: the tadpole “decided” to swim. Modelling emphasises uncertainties about fine unmyelinated axon physiology but, when informed by biological data, makes general predictions about gap junctions: locations close to the soma; relatively small numbers; many indirect connections between neurons; cause of action potential propagation failure in fine axons; misleading alteration of intrinsic firing

  10. The impact of the perception of rhythmic music on self-paced oscillatory movements.

    PubMed

    Peckel, Mathieu; Pozzo, Thierry; Bigand, Emmanuel

    2014-01-01

    Inspired by theories of perception-action coupling and embodied music cognition, we investigated how rhythmic music perception impacts self-paced oscillatory movements. In a pilot study, we examined the kinematic parameters of self-paced oscillatory movements, walking and finger tapping using optical motion capture. In accordance with biomechanical constraints accounts of motion, we found that movements followed a hierarchical organization depending on the proximal/distal characteristic of the limb used. Based on these findings, we were interested in knowing how and when the perception of rhythmic music could resonate with the motor system in the context of these constrained oscillatory movements. In order to test this, we conducted an experiment where participants performed four different effector-specific movements (lower leg, whole arm and forearm oscillation and finger tapping) while rhythmic music was playing in the background. Musical stimuli consisted of computer-generated MIDI musical pieces with a 4/4 metrical structure. The musical tempo of each song increased from 60 BPM to 120 BPM by 6 BPM increments. A specific tempo was maintained for 20 s before a 2 s transition to the higher tempo. The task of the participant was to maintain a comfortable pace for the four movements (self-paced) while not paying attention to the music. No instruction on whether to synchronize with the music was given. Results showed that participants were distinctively influenced by the background music depending on the movement used with the tapping task being consistently the most influenced. Furthermore, eight strategies put in place by participants to cope with the task were unveiled. Despite not instructed to do so, participants also occasionally synchronized with music. Results are discussed in terms of the link between perception and action (i.e., motor/perceptual resonance). In general, our results give support to the notion that rhythmic music is processed in a motoric

  11. Intermittent rhythmic delta activity (IRDA) in a patient with band heterotopia.

    PubMed

    Nakano, M; Abe, K; Ono, J; Yanagihara, T

    1998-07-01

    We report a patient with band heterotopia whose electroencephalogram (EEG) showed typical morphological features of intermittent rhythmic delta activity (IRDA). This 18-year-old woman had complex partial seizures. Neuropsychometry revealed mental dysfunction. Magnetic resonance imaging (MRI) showed bilaterally symmetrical layer of heterotopic gray matter in deep white matter over the frontal, parietal and occipital regions. This case is the first report of IRDA detected in band heterotopia.

  12. NIR spectroscopic measurement of local muscle metabolism during rhythmic, sustained, and intermittent handgrip exercise

    NASA Astrophysics Data System (ADS)

    van Beekvelt, Mireille C. P.; Orbon, Karin; van Engelen, Baziel G. M.; Wevers, Ron A.; Colier, Willy N. J. M.

    2003-10-01

    The aim of this study was to investigate local muscle oxygen consumption (mVO2) during various protocols of isometric handgrip exercise. mVO2was measured by near-infrared spectroscopy (NIRS) during sustained, rhythmic, and intermittent isometric handgrip exercise. Whereas rhythmic handgrip exercise has the advantage that local muscle metabolism can be measured over the full range from low- to high-intensity work, the advantage of sustained handgrip exercise is that it is less prone to movement artifacts. Intermittent isometric handgrip exercise enables calculation of mVO2 at short time intervals providing information about the time response of local oxygen consumption in relation to the onset of exercise. Ten healthy subjects participated in this study. The different protocols were performed on separate days and in random order. mVO2 during rhythmic exercise was significantly higher than that during sustained exercise at all work intensities tested (P <= 0.05). However, the highest oxygen consumption value for the three exercise protocols was measured during the steady state of intermittent exercise (P <= 0.05). These results show that the measurement of task-specific muscle metabolism during exercise can be measured noninvasively and with relative ease by near-infrared spectroscopy.

  13. Persistent diel melatonin rhythmicity during the Arctic summer in free-living willow warblers.

    PubMed

    Silverin, Bengt; Gwinner, Eberhard; Van't Hof, Thomas J; Schwabl, Ingrid; Fusani, Leonida; Hau, Michaela; Helm, Barbara

    2009-06-01

    Arctic environments are challenging for circadian systems. Around the solstices, the most important zeitgeber, the change between night and day, is reduced to minor fluctuations in light intensities. However, many species including songbirds nonetheless show clear diel activity patterns. Here we examine the possible physiological basis underlying diel rhythmicity under continuous Arctic summer light. Rhythmic secretion of the hormone melatonin constitutes an important part of the songbird circadian system and its experimental suppression, e.g., by constant light, usually leads to behavioral arrhythmia. We therefore studied melatonin patterns in a free-living migratory songbird, the willow warbler (Phylloscopus trochilus), that maintains diel activity during the Arctic summer. We compared melatonin profiles during late spring and summer solstice in two Swedish populations from the south (58 degrees N) and near the Arctic circle (66 degrees N). We found the northern Swedish population maintained clear diel changes in melatonin secretion during the summer solstice, although peak concentrations were lower than in southern Sweden. Melatonin levels were highest before midnight and in good accordance with periods of reduced activity. The maintenance of diel melatonin rhythmicity under conditions of continuous light may be one of the physiological mechanisms that enables continued functioning of the circadian system.

  14. Rhythmic control of AANAT translation by hnRNP Q in circadian melatonin production.

    PubMed

    Kim, Tae-Don; Woo, Kyung-Chul; Cho, Sungchan; Ha, Dae-Cheong; Jang, Sung Key; Kim, Kyong-Tai

    2007-04-01

    The circadian rhythm of pineal melatonin requires the nocturnal increment of serotonin N-acetyltransferase (arylalkylamine N-acetyltransferase [AANAT]) protein. To date, only limited information is available in the critical issue of how AANAT protein expression is up-regulated exclusively at night regardless of its species-specific mRNA profiles. Here we show that the circadian timing of AANAT protein expression is regulated by rhythmic translation of AANAT mRNA. This rhythmic control is mediated by both a highly conserved IRES (internal ribosome entry site) element within the AANAT 5' untranslated region and its partner hnRNP Q (heterogeneous nuclear ribonucleoprotein Q) with a peak in the middle of the night. Consistent with the enhancing role of hnRNP Q in AANAT IRES activities, knockdown of the hnRNP Q level elicited a dramatic decrease of peak amplitude in the AANAT protein profile parallel to reduced melatonin production in pinealocytes. This translational regulation of AANAT mRNA provides a novel aspect for achieving the circadian rhythmicity of vertebrate melatonin.

  15. Intermittent visual feedback can boost motor learning of rhythmic movements: evidence for error feedback beyond cycles.

    PubMed

    Ikegami, Tsuyoshi; Hirashima, Masaya; Osu, Rieko; Nozaki, Daichi

    2012-01-11

    Movement error is a driving force behind motor learning. For motor learning with discrete movements, such as point-to-point reaching, it is believed that the brain uses error information of the immediately preceding movement only. However, in the case of continuous and repetitive movements (i.e., rhythmic movements), there is a ceaseless inflow of performance information. Thus, an accurate temporal association of the motor commands with the resultant movement errors is not necessarily guaranteed. We investigated how the brain overcomes this challenging situation. Human participants adapted rhythmic movements between two targets to visuomotor rotations, the amplitudes of which changed randomly from cycle to cycle (the duration of one cycle was ∼400 ms). A system identification technique revealed that the motor adaptation was affected not just by the preceding movement error, but also by a history of errors from the previous cycles. Error information obtained from more than one previous cycle tended to increase, rather than decrease, movement error. This result led to a counterintuitive prediction: providing visual error feedback for only a fraction of cycles should enhance visuomotor adaptation. As predicted, we observed that motor adaptation to a constant visual rotation (30°) was significantly enhanced by providing visual feedback once every fourth or fifth cycle rather than for every cycle. These results suggest that the brain requires a specific processing time to modify the motor command, based on the error information, and so is unable to deal appropriately with the overwhelming flow of error information generated during rhythmic movements.

  16. How Moving Together Brings Us Together: When Coordinated Rhythmic Movement Affects Cooperation.

    PubMed

    Cross, Liam; Wilson, Andrew D; Golonka, Sabrina

    2016-01-01

    Although it is well established that rhythmically coordinating with a social partner can increase cooperation, it is as yet unclear when and why intentional coordination has such effects. We distinguish three dimensions along which explanations might vary. First, pro-social effects might require in-phase synchrony or simply coordination. Second, the effects of rhythmic movements on cooperation might be direct or mediated by an intervening variable. Third, the pro-social effects might occur in proportion to the quality of the coordination, or occur once some threshold amount of coordination has occurred. We report an experiment and two follow-ups which sought to identify which classes of models are required to account for the positive effects of coordinated rhythmic movement on cooperation. Across the studies, we found evidence (1) that coordination, and not just synchrony, can have pro-social consequences (so long as the social nature of the task is perceived), (2) that the effects of intentional coordination are direct, not mediated, and (3) that the degree of the coordination did not predict the degree of cooperation. The fact of inter-personal coordination (moving together in time and in a social context) is all that's required for pro-social effects. We suggest that future research should use the kind of carefully controllable experimental task used here to continue to develop explanations for when and why coordination affects pro-social behaviors.

  17. Energy efficient and robust rhythmic limb movement by central pattern generators.

    PubMed

    Verdaasdonk, B W; Koopman, H F J M; Helm, F C T Van Der

    2006-05-01

    Humans show great energy efficiency and robustness in rhythmic tasks, such as walking and arm swinging. In this study a mathematical model of rhythmic limb movement is presented, which shows that tight local coupling of Central Pattern Generators (CPGs) to limbs could explain part of this behavior. Afferent feedback to flexor and extensor centers of the CPG is crucial in providing energy efficiency by means of resonance tuning. Feedback of positional information provides resonance tuning above the endogenous frequency of the CPG. Integral feedback provides resonance tuning at and below the endogenous frequency. Feedback of velocity information is necessary to compensate for the time delay in the loop, coupling limb to CPG; without velocity feedback bi-stability occurs and resonance tuning is not possible at high movement frequencies. The concepts of energy efficient and robust control of rhythmic limb movements are also applicable to robotics. It is the first CPG model, which provides resonance tuning at natural limb frequencies above and below its endogenous frequency.

  18. How Moving Together Brings Us Together: When Coordinated Rhythmic Movement Affects Cooperation

    PubMed Central

    Cross, Liam; Wilson, Andrew D.; Golonka, Sabrina

    2016-01-01

    Although it is well established that rhythmically coordinating with a social partner can increase cooperation, it is as yet unclear when and why intentional coordination has such effects. We distinguish three dimensions along which explanations might vary. First, pro-social effects might require in-phase synchrony or simply coordination. Second, the effects of rhythmic movements on cooperation might be direct or mediated by an intervening variable. Third, the pro-social effects might occur in proportion to the quality of the coordination, or occur once some threshold amount of coordination has occurred. We report an experiment and two follow-ups which sought to identify which classes of models are required to account for the positive effects of coordinated rhythmic movement on cooperation. Across the studies, we found evidence (1) that coordination, and not just synchrony, can have pro-social consequences (so long as the social nature of the task is perceived), (2) that the effects of intentional coordination are direct, not mediated, and (3) that the degree of the coordination did not predict the degree of cooperation. The fact of inter-personal coordination (moving together in time and in a social context) is all that's required for pro-social effects. We suggest that future research should use the kind of carefully controllable experimental task used here to continue to develop explanations for when and why coordination affects pro-social behaviors. PMID:28066301

  19. Energy deprivation transiently enhances rhythmic inhibitory events in the CA3 hippocampal network in vitro.

    PubMed

    Gee, C E; Benquet, P; Demont-Guignard, S; Wendling, F; Gerber, U

    2010-07-14

    Oxygen glucose deprivation (OGD) leads to rapid suppression of synaptic transmission. Here we describe an emergence of rhythmic activity at 8 to 20 Hz in the CA3 subfield of hippocampal slice cultures occurring for a few minutes prior to the OGD-induced cessation of evoked responses. These oscillations, dominated by inhibitory events, represent network activity, as they were abolished by tetrodotoxin. They were also completely blocked by the GABAergic antagonist picrotoxin, and strongly reduced by the glutamatergic antagonist NBQX. Applying CPP to block NMDA receptors had no effect and neither did UBP302, an antagonist of GluK1-containing kainate receptors. The gap junction blocker mefloquine disrupted rhythmicity. Simultaneous whole-cell voltage-clamp recordings from neighboring or distant CA3 pyramidal cells revealed strong cross-correlation of the incoming rhythmic activity. Interneurons in the CA3 area received similar correlated activity. Interestingly, oscillations were much less frequently observed in the CA1 area. These data, together with the observation that the recorded activity consists primarily of inhibitory events, suggest that CA3 interneurons are important for generating these oscillations. This transient increase in inhibitory network activity during OGD may represent a mechanism contributing to the lower vulnerability to ischemic insults of the CA3 area as compared to the CA1 area.

  20. Modification of cortically evoked rhythmic jaw movements by reflex deglutition in rabbits.

    PubMed

    Sumi, T

    1977-01-01

    In rabbits, lightly anesthetized with ether, tetanic stimulation of the superior laryngeal nerve (SLN) displaced the jaw toward opening and reduced the amplitude of cortically evoked rhythmic jaw movements. With increased intensity of stimulus, the effects became remarkable and the opened jaw movement ultimately ceased. Reflex swallowing in reaction to weak electrical stimuli of SLN or to a small amount of water squirted into the oropharynx yielded a brief and instantaneous cessation of rhythmic jaw movements with the jaw open. Strong electrical stimuli to the nerve or a squirt of relatively large amount of water into the oropharynx prolonged the duration of both swallowing and the cessation of rhythmic jaw movements for about 1.0 sec. Reflex swallowing yielded a burst of activity for about 300 msec in the mylohyoideus and silence for a longer period in the masseter. Spontaneous activity of the masseter was moderately decreased during the nerve stimulation and, when swallowing occurred, this decrease became prominent for a short period.

  1. Effect of Rhythmic Auditory Stimulation on Gait in Parkinsonian Patients with and without Freezing of Gait

    PubMed Central

    Arias, Pablo; Cudeiro, Javier

    2010-01-01

    Freezing of gait (FOG) in Parkinson's disease (PD) rises in prevalence when the effect of medications decays. It is known that auditory rhythmic stimulation improves gait in patients without FOG (PD-FOG), but its putative effect on patients with FOG (PD+FOG) at the end of dose has not been evaluated yet. This work evaluates the effect of auditory rhythmic stimulation on PD+FOG at the end of dose. 10 PD+FOG and 9 PD-FOG patients both at the end of dose periods, and 10 healthy controls were asked to perform several walking tasks. Tasks were performed in the presence and absence of auditory sensory stimulation. All PD+FOG suffered FOG during the task. The presence of auditory rhythmic stimulation (10% above preferred walking cadence) led PD+FOG to significantly reduce FOG. Velocity and cadence were increased, and turn time reduced in all groups. We conclude that auditory stimulation at the frequency proposed may be useful to avoid freezing episodes in PD+FOG. PMID:20339591

  2. Shear flow over a self-similar expanding pulmonary alveolus during rhythmical breathing

    NASA Astrophysics Data System (ADS)

    Haber, S.; Butler, J. P.; Brenner, H.; Emanuel, I.; Tsuda, A.

    2000-02-01

    Alternating shear flow over a self-similar, rhythmically expanding hemispherical depression is investigated. It provides a fluid-mechanical model for an alveolated respiratory unit, by means of which the effect of lung rhythmical expansion on gas mixing as well as aerosol dispersion and deposition can be studied. The flow is assumed to be very slow and governed by the quasi-steady linear Stokes equations. Consequently, superposition of the following two cases provides an easy route toward characterizing the aforementioned flow field. The first case treats the flow field that is generated by a rhythmically expanding spherical cap (the alveolus). The cap is attached at its rim to a circular opening in an expanding unbounded plane bounding a semi-infinite fluid region. The rate of expansion of the cap and the plane are chosen such as to maintain the system's configurational self-similarity. The second case addresses the flow disturbance that is generated by an alternating shear flow encountering a rigid hemispherical cavity in a plane bounding a semi-infinite fluid domain.

  3. Effect of rhythmic auditory stimulation on gait kinematic parameters of patients with multiple sclerosis

    PubMed Central

    Shahraki, M; Sohrabi, M; Taheri Torbati, HR; Nikkhah, K; NaeimiKia, M

    2017-01-01

    Purpose: This study aimed to examine the effect of rhythmic auditory stimulation on gait kinematic parameters of patients with multiple sclerosis. Subjects and Methods: In this study, 18 subjects, comprising 4 males and 14 females with Multiple Sclerosis with expanded disability status scale of 3 to 6 were chosen. Subjects were selected by available and targeted sampling and were randomly divided into two experimental (n = 9) and control (n = 9) groups. Exercises were gait with rhythmic auditory stimulation by a metronome device, in addition to gait without stimulation for the experimental and control groups, respectively. Training was carried out for 3 weeks, with 30 min duration for each session 3 times a week. Stride length, stride time, double support time, cadence and gait speed were measured by motion analysis device. Results: There was a significant difference between stride length, stride time, double support time, cadence and gait speed in the experimental group, before and after the training. Furthermore, there was a significant difference between the experimental and control groups in the enhancement of stride length, stride time, cadence and gait speed in favor of the experimental group. While this difference was not significant for double support time. Conclusion: The results of this study showed that rhythmic auditory stimulation is an effective rehabilitation method to improve gait kinematic parameters in patients with multiple sclerosis. PMID:28255373

  4. Early development of circadian rhythmicity in the suprachiamatic nuclei and pineal gland of teleost, flounder (Paralichthys olivaeus), embryos.

    PubMed

    Mogi, Makoto; Uji, Susumu; Yokoi, Hayato; Suzuki, Tohru

    2015-08-01

    Circadian rhythms enable organisms to coordinate multiple physiological processes and behaviors with the earth's rotation. In mammals, the suprachiasmatic nuclei (SCN), the sole master circadian pacemaker, has entrainment mechanisms that set the circadian rhythm to a 24-h cycle with photic signals from retina. In contrast, the zebrafish SCN is not a circadian pacemaker, instead the pineal gland (PG) houses the major circadian oscillator. The SCN of flounder larvae, unlike that of zebrafish, however, expresses per2 with a rhythmicity of daytime/ON and nighttime/OFF. Here, we examined whether the rhythm of per2 expression in the flounder SCN represents the molecular clock. We also examined early development of the circadian rhythmicity in the SCN and PG. Our three major findings were as follows. First, rhythmic per2 expression in the SCN was maintained under 24 h dark (DD) conditions, indicating that a molecular clock exists in the flounder SCN. Second, onset of circadian rhythmicity in the SCN preceded that in the PG. Third, both 24 h light (LL) and DD conditions deeply affected the development of circadian rhythmicity in the SCN and PG. This is the first report dealing with the early development of circadian rhythmicity in the SCN in fish.

  5. Characterisation of Development and Electrophysiological Mechanisms Underlying Rhythmicity of the Avian Lymph Heart

    PubMed Central

    Jaffer, Sajjida; Valasek, Petr; Luke, Graham; Batarfi, Munirah; Whalley, Benjamin Jason; Patel, Ketan

    2016-01-01

    Despite significant advances in tissue engineering such as the use of scaffolds, bioreactors and pluripotent stem cells, effective cardiac tissue engineering for therapeutic purposes has remained a largely intractable challenge. For this area to capitalise on such advances, a novel approach may be to unravel the physiological mechanisms underlying the development of tissues that exhibit rhythmic contraction yet do not originate from the cardiac lineage. Considerable attention has been focused on the physiology of the avian lymph heart, a discrete organ with skeletal muscle origins yet which displays pacemaker properties normally only found in the heart. A functional lymph heart is essential for avian survival and growth in ovo. The histological nature of the lymph heart is similar to skeletal muscle although molecular and bioelectrical characterisation during development to assess mechanisms that contribute towards lymph heart contractile rhythmicity have not been undertaken. A better understanding of these processes may provide exploitable insights for therapeutic rhythmically contractile tissue engineering approaches in this area of significant unmet clinical need. Here, using molecular and electrophysiological approaches, we describe the molecular development of the lymph heart to understand how this skeletal muscle becomes fully functional during discrete in ovo stages of development. Our results show that the lymph heart does not follow the normal transitional programme of myogenesis as documented in most skeletal muscle, but instead develops through a concurrent programme of precursor expansion, commitment to myogenesis and functional differentiation which offers a mechanistic explanation for its rapid development. Extracellular electrophysiological field potential recordings revealed that the peak-to-peak amplitude of electrically evoked local field potentials elicited from isolated lymph heart were significantly reduced by treatment with carbachol; an

  6. Effects of Articulation Styles on Perception of Modulated Tempos in Violin Excerpts

    ERIC Educational Resources Information Center

    Geringer, John M.; Madsen, Clifford K.; Macleod, Rebecca B.

    2007-01-01

    We investigated effects of legato, staccato and pizzicato articulation styles on the perception of modulated tempos. Seventy-two music majors served as participants. Two solo violin excerpts were chosen with contrasting rhythmic rates and were recorded in all three articulation styles. Examples were presented to listeners in three conditions of…

  7. Development of aircraft lavatory compartments with improved fire resistance characteristics, phase 1: Fire containment test of a wide body aircraft lavatory module

    NASA Technical Reports Server (NTRS)

    Anderson, R. A.; Arnold, D. B.; Johnson, G. A.; Tustin, E. A.

    1978-01-01

    A test was conducted to evaluate the fire containment characteristics of a Boeing 747 lavatory module. Results showed that the fire was contained within the lavatory during the 30-minute test period with the door closed. The resistance of the lavatory wall and ceiling panels and general lavatory construction to burn-through under the test conditions was demonstrated.

  8. Mechano-sensitivity of cardiac pacemaker function: Pathophysiological relevance, experimental implications, and conceptual integration with other mechanisms of rhythmicity

    PubMed Central

    Quinn, T. Alexander; Kohl, Peter

    2012-01-01

    Cardiac pacemaker cells exhibit spontaneous, rhythmic electrical excitation, termed automaticity. This automatic initiation of action potentials requires spontaneous diastolic depolarisation, whose rate determines normal rhythm generation in the heart. Pacemaker mechanisms have been split recently into: (i) cyclic changes in trans-sarcolemmal ion flows (termed the ‘membrane-clock’), and (ii) rhythmic intracellular calcium cycling (the ‘calcium-clock’). These two ‘clocks’ undoubtedly interact, as trans-sarcolemmal currents involved in pacemaking include calcium-carrying mechanisms, while intracellular calcium cycling requires trans-sarcolemmal ion flux as the mechanism by which it affects membrane potential. The split into separate ‘clocks’ is, therefore, somewhat arbitrary. Nonetheless, the ‘clock’ metaphor has been conceptually stimulating, in particular since there is evidence to support the view that either ‘clock’ could be sufficient in principle to set the rate of pacemaker activation. Of course, the same has also been shown for sub-sets of ‘membrane-clock’ ion currents, illustrating the redundancy of mechanisms involved in maintaining such basic functionality as the heartbeat, a theme that is common for vital physiological systems. Following the conceptual path of identifying individual groups of sub-mechanisms, it is important to remember that the heart is able to adapt pacemaker rate to changes in haemodynamic load, even after isolation or transplantation, and on a beat-by-beat basis. Neither the ‘membrane-’ nor the ‘calcium-clock’ do, as such, inherently account for this rapid adaptation to circulatory demand (cellular Ca2+ balance changes over multiple beats, while variation of sarcolemmal ion channel presence takes even longer). This suggests that a third set of mechanisms must be involved in setting the pace. These mechanisms are characterised by their sensitivity to the cyclically changing mechanical environment, and

  9. Treadmill walking is not equivalent to overground walking for the study of walking smoothness and rhythmicity in older adults.

    PubMed

    Row Lazzarini, Brandi S; Kataras, Theodore J

    2016-05-01

    Treadmills are appealing for gait studies, but some gait mechanics are disrupted during treadmill walking. The purpose of this study was to examine the effects of speed and treadmill walking on walking smoothness and rhythmicity of 40 men and women between the ages of 70-96 years. Gait smoothness was examined during overground (OG) and treadmill (TM) walking by calculating the harmonic ratio from linear accelerations measured at the level of the lumbar spine. Rhythmicity was quantified as the stride time standard deviation. TM walking was performed at two speeds: a speed matching the natural OG walk speed (TM-OG), and a preferred TM speed (PTM). A dual-task OG condition (OG-DT) was evaluated to determine if TM walking posed a similar cognitive challenge. Statistical analysis included a one-way Analysis of Variance with Bonferroni corrected post hoc comparisons and the Wilcoxon signed rank test for non-normally distributed variables. Average PTM speed was slower than OG. Compared to OG, those who could reach the TM-OG speed (74.3% of sample) exhibited improved ML smoothness and rhythmicity, and the slower PTM caused worsened vertical and AP smoothness, but did not affect rhythmicity. PTM disrupted smoothness and rhythmicity differently than the OG-DT condition, likely due to reduced speed. The use of treadmills for gait smoothness and rhythmicity studies in older adults is problematic; some participants will not achieve OG speed during TM walking, walking at the TM-OG speed artificially improves rhythmicity and ML smoothness, and walking at the slower PTM speed worsens vertical and AP gait smoothness.

  10. Ventrolateral Origin of Each Cycle of Rhythmic Activity Generated by the Spinal Cord of the Chick Embryo

    PubMed Central

    Arai, Yoshiyasu; Mentis, George Z.; Wu, Jiang-young; O'Donovan, Michael J.

    2007-01-01

    Background The mechanisms responsible for generating rhythmic motor activity in the developing spinal cord of the chick embryo are poorly understood. Here we investigate whether the activity of motoneurons occurs before other neuronal populations at the beginning of each cycle of rhythmic discharge. Methodology/Principal Findings The spatiotemporal organization of neural activity in transverse slices of the lumbosacral cord of the chick embryo (E8-E11) was investigated using intrinsic and voltage-sensitive dye (VSD) imaging. VSD signals accompanying episodes of activity comprised a rhythmic decrease in light transmission that corresponded to each cycle of electrical activity recorded from the ipsilateral ventral root. The rhythmic signals were widely synchronized across the cord face, and the largest signal amplitude was in the ventrolateral region where motoneurons are located. In unstained slices we recorded two classes of intrinsic signal. In the first, an episode of rhythmic activity was accompanied by a slow decrease in light transmission that peaked in the dorsal horn and decayed dorsoventrally. Superimposed on this signal was a much smaller rhythmic increase in transmission that was coincident with each cycle of discharge and whose amplitude and spatial distribution was similar to that of the VSD signals. At the onset of a spontaneously occurring episode and each subsequent cycle, both the intrinsic and VSD signals originated within the lateral motor column and spread medially and then dorsally. By contrast, following a dorsal root stimulus, the optical signals originated within the dorsal horn and traveled ventrally to reach the lateral motor column. Conclusions/Significance These findings suggest that motoneuron activity contributes to the initiation of each cycle of rhythmic activity, and that motoneuron and/or R-interneuron synapses are a plausible site for the activity-dependent synaptic depression that modeling studies have identified as a critical

  11. Salvinorin-A Induces Intense Dissociative Effects, Blocking External Sensory Perception and Modulating Interoception and Sense of Body Ownership in Humans

    PubMed Central

    Maqueda, Ana Elda; Valle, Marta; Addy, Peter H.; Antonijoan, Rosa Maria; Puntes, Montserrat; Coimbra, Jimena; Ballester, Maria Rosa; Garrido, Maite; González, Mireia; Claramunt, Judit; Barker, Steven; Johnson, Matthew W.; Griffiths, Roland R.

    2015-01-01

    Background: Salvinorin-A is a terpene with agonist properties at the kappa-opioid receptor, the binding site of endogenous dynorphins. Salvinorin-A is found in Salvia divinorum, a psychoactive plant traditionally used by the Mazatec people of Oaxaca, Mexico, for medicinal and spiritual purposes. Previous studies with the plant and salvinorin-A have reported psychedelic-like changes in perception, but also unusual changes in body awareness and detachment from external reality. Here we comprehensively studied the profiles of subjective effects of increasing doses of salvinorin-A in healthy volunteers, with a special emphasis on interoception. Methods: A placebo and three increasing doses of vaporized salvinorin-A (0.25, 0.50, and 1mg) were administered to eight healthy volunteers with previous experience in the use of psychedelics. Drug effects were assessed using a battery of questionnaires that included, among others, the Hallucinogen Rating Scale, the Altered States of Consciousness, and a new instrument that evaluates different aspects of body awareness: the Multidimensional Assessment for Interoceptive Awareness. Results: Salvinorin-A led to a disconnection from external reality, induced elaborate visions and auditory phenomena, and modified interoception. The lower doses increased somatic sensations, but the highest dose led to a sense of a complete loss of contact with the body. Conclusions: Salvinorin-A induced intense psychotropic effects characterized by a dose-dependent gating of external audio-visual information and an inverted-U dose-response effect on body awareness. These results suggest a prominent role for the kappa opioid receptor in the regulation of sensory perception, interoception, and the sense of body ownership in humans. PMID:26047623

  12. Synthesis of high-complexity rhythmic signals for closed-loop electrical neuromodulation.

    PubMed

    Zalay, Osbert C; Bardakjian, Berj L

    2013-06-01

    We propose an approach to synthesizing high-complexity rhythmic signals for closed-loop electrical neuromodulation using cognitive rhythm generator (CRG) networks, wherein the CRG is a hybrid oscillator comprised of (1) a bank of neuronal modes, (2) a ring device (clock), and (3) a static output nonlinearity (mapper). Networks of coupled CRGs have been previously implemented to simulate the electrical activity of biological neural networks, including in silico models of epilepsy, producing outputs of similar waveform and complexity to the biological system. This has enabled CRG network models to be used as platforms for testing seizure control strategies. Presently, we take the application one step further, envisioning therapeutic CRG networks as rhythmic signal generators creating neuromimetic signals for stimulation purposes, motivated by recent research indicating that stimulus complexity and waveform characteristics influence neuromodulation efficacy. To demonstrate this concept, an epileptiform CRG network generating spontaneous seizure-like events (SLEs) was coupled to a therapeutic CRG network, forming a closed-loop neuromodulation system. SLEs are associated with low-complexity dynamics and high phase coherence in the network. The tuned therapeutic network generated a high-complexity, multi-banded rhythmic stimulation signal with prominent theta and gamma-frequency power that suppressed SLEs and increased dynamic complexity in the epileptiform network, as measured by a relative increase in the maximum Lyapunov exponent and decrease in phase coherence. CRG-based neuromodulation outperformed both low and high-frequency periodic pulse stimulation, suggesting that neuromodulation using complex, biomimetic signals may provide an improvement over conventional electrical stimulation techniques for treating neurological disorders such as epilepsy.

  13. "It's Always the Judge's Fault": Attention, Emotion Recognition, and Expertise in Rhythmic Gymnastics Assessment.

    PubMed

    van Bokhorst, Lindsey G; Knapová, Lenka; Majoranc, Kim; Szebeni, Zea K; Táborský, Adam; Tomić, Dragana; Cañadas, Elena

    2016-01-01

    In many sports, such as figure skating or gymnastics, the outcome of a performance does not rely exclusively on objective measurements, but on more subjective cues. Judges need high attentional capacities to process visual information and overcome fatigue. Also their emotion recognition abilities might have an effect in detecting errors and making a more accurate assessment. Moreover, the scoring given by judges could be also influenced by their level of expertise. This study aims to assess how rhythmic gymnastics judges' emotion recognition and attentional abilities influence accuracy of performance assessment. Data will be collected from rhythmic gymnastics judges and coaches at different international levels. This study will employ an online questionnaire consisting on an emotion recognition test and attentional test. Participants' task is to watch a set of videotaped rhythmic gymnastics performances and evaluate them on the artistic and execution components of performance. Their scoring will be compared with the official scores given at the competition the video was taken from to measure the accuracy of the participants' evaluations. The proposed research represents an interdisciplinary approach that integrates cognitive and sport psychology within experimental and applied contexts. The current study advances the theoretical understanding of how emotional and attentional aspects affect the evaluation of sport performance. The results will provide valuable evidence on the direction and strength of the relationship between the above-mentioned factors and the accuracy of sport performance evaluation. Importantly, practical implications might be drawn from this study. Intervention programs directed at improving the accuracy of judges could be created based on the understanding of how emotion recognition and attentional abilities are related to the accuracy of performance assessment.

  14. The computational and neural basis of rhythmic timing in medial premotor cortex.

    PubMed

    Merchant, Hugo; Averbeck, Bruno B

    2017-03-23

    The neural underpinnings of rhythmic behavior, including music and dance, have been studied using the synchronization-continuation task (SCT), where subjects initially tap in synchrony with an isochronous metronome and then keep tapping at a similar rate via an internal beat mechanism. Here, we provide behavioral and neural evidence that supports a resetting drift-diffusion model (DDM) during SCT. Behaviorally, we show the model replicates the linear relation between the mean and standard-deviation of the intervals produced by monkeys in SCT. We then show that neural populations in the medial premotor cortex (MPC) contain an accurate trial-by-trial representation of elapsed-time between taps. Interestingly, the autocorrelation structure of the elapsed-time representation is consistent with a DDM. These results indicate that MPC has an orderly representation of time with features characteristic of concatenated DDMs and that this population signal can be used to orchestrate the rhythmic structure of the internally timed elements of SCT.SIGNIFICANCE STATEMENTThe present study used behavioral data, ensemble recordings from medial premotor cortex (MPC) in macaque monkeys, and computational modeling, to establish evidence in favor of a class of drift-diffusion models of rhythmic timing during a synchronization-continuation tapping task (SCT). The linear relation between the mean and standard-deviation of the intervals produced by monkeys in SCT is replicated by the model. Populations of MPC cells faithfully represent the elapsed time between taps, and there is significant trial-by-trial relation between decoded times and the timing behavior of the monkeys. Notably, the neural decoding properties, including its autocorrelation structure are consistent with a set of drift-diffusion models that are arranged sequentially and that are resetting in each SCT tap.

  15. Daily Rhythmicity of Clock Gene Transcripts in Atlantic Cod Fast Skeletal Muscle

    PubMed Central

    Lazado, Carlo C.; Kumaratunga, Hiruni P. S.; Nagasawa, Kazue; Babiak, Igor; Giannetto, Alessia; Fernandes, Jorge M. O.

    2014-01-01

    The classical notion of a centralized clock that governs circadian rhythmicity has been challenged with the discovery of peripheral oscillators that enable organisms to cope with daily changes in their environment. The present study aimed to identify the molecular clock components in Atlantic cod (Gadus morhua) and to investigate their daily gene expression in fast skeletal muscle. Atlantic cod clock genes were closely related to their orthologs in teleosts and tetrapods. Synteny was conserved to varying degrees in the majority of the 18 clock genes examined. In particular, aryl hydrocarbon receptor nuclear translocator-like 2 (arntl2), RAR-related orphan receptor A (rora) and timeless (tim) displayed high degrees of conservation. Expression profiling during the early ontogenesis revealed that some transcripts were maternally transferred, namely arntl2, cryptochrome 1b and 2 (cry1b and cry2), and period 2a and 2b (per2a and per2b). Most clock genes were ubiquitously expressed in various tissues, suggesting the possible existence of multiple peripheral clock systems in Atlantic cod. In particular, they were all detected in fast skeletal muscle, with the exception of neuronal PAS (Per-Arnt-Single-minded) domain-containing protein (npas1) and rora. Rhythmicity analysis revealed 8 clock genes with daily rhythmic expression, namely arntl2, circadian locomotor output cycles kaput (clock), npas2, cry2, cry3 per2a, nuclear receptor subfamily 1, group D, member 1 (nr1d1), and nr1d2a. Transcript levels of the myogenic genes myogenic factor 5 (myf5) and muscleblind-like 1 (mbnl1) strongly correlated with clock gene expression. This is the first study to unravel the molecular components of peripheral clocks in Atlantic cod. Taken together, our data suggest that the putative clock system in fast skeletal muscle of Atlantic cod has regulatory implications on muscle physiology, particularly in the expression of genes related to myogenesis. PMID:24921252

  16. Ballroom dance and body size perception.

    PubMed

    Fonseca, Cristiane Costa; Thurm, Bianca Elisabeth; Vecchi, Rodrigo Luiz; Gama, Eliane Florencio

    2014-10-01

    Ballroom dancing consists in the performance of rhythmic movements guided by music, which provide sensorimotor integration and stimulate feelings. The body schema is the unconscious sensorimotor representation that allows the individual to perceive his anatomical body in space. Comprising tactile, proprioceptive, kinesthetic, and environmental information, it is directly related to movement. The aim of this study was to investigate the influence of non-competitive practice of ballroom dancing on body perception. The projection point test was applied to 30 volunteers before and after a period of 3 mo.; 15 controls attended lectures on body perception and 15 participants took dance lessons. It was observed that ballroom dancing brought perceptual benefits for those who practiced it.

  17. Rhythmic variation in heart rate and respiration rate during space flight - Apollo 15

    NASA Technical Reports Server (NTRS)

    Rummel, J. A.

    1974-01-01

    As part of the operational biomedical monitoring for Apollo manned missions, ECG and respiration rate are telemetered at selected intervals to mission control. The data were collected as part of this monitoring program. These data were evaluated for circadian and ultradian rhythmicity because of their uniqueness. The ability to detect and quantitate biorhythms in living systems during space flight is an important aspect of evaluating hypotheses concerning the underlying mechanisms of these phenomena. Circadian variation in heart rate during space flight is demonstrated here. In analyzing generated time series data it has been found that period discrimination is much better than the theoretical limit.

  18. Rhythmical intention as a method of treatment for the cerebral palsied patient.

    PubMed

    Clarke, J; Evans, E

    1973-06-01

    Conductive Education as described by Cotton (1967, 1970) and Hari (1968) is the method of treatment introduced by Professor Andreas Peto at the State Institute for the Motor Disabled in Budapest. It is a system of treatment which does not separate the learning of intellectual, linguistic and functional skills into the usual areas of school, speech therapy, occupational therapy and physiotherapy. Instead the child approaches a total learning situation where the conductor is teacher/therapist and Rhythmical Intention is used as the method of learning all tasks.

  19. Effects of inclined treadmill walking training with rhythmic auditory stimulation on balance and gait in stroke patients

    PubMed Central

    Yoon, Sung Kyeung; Kang, Soon Hee

    2016-01-01

    [Purpose] The purpose of this study was to determine if an inclined treadmill with rhythmic auditory stimulation gait training can improve balance and gait ability in stroke patients. [Subjects and Methods] Thirty participants were randomly divided into three groups: inclined treadmill with rhythmic auditory stimulation training group (n=10), inclined treadmill training group (n=10), and treadmill training group (n=10). For all groups, the training was conducted for 4 weeks, 30 minutes per session, 5 times per week. Two subjects dropped out before study completion. [Results] All variables of balance and gait, except for the timed up and go test in the treadmill group, significantly improved in all groups. Moreover, all variables showed a more significant improvement in the inclined treadmill with rhythmic auditory stimulation group when compared with the other groups. Timed up and go test, Berg balance scale, 6 m walking test, walking speed, and symmetric index were significantly improved in the inclined treadmill group when compared with the treadmill group. [Conclusion] Thus, for stroke patients receiving gait training, inclined treadmill with rhythmic auditory stimulation training was more effective in maintaining balance and gait than inclined treadmill without rhythmic auditory stimulation or only treadmill training. PMID:28174453

  20. How sleep and wakefulness influence circadian rhythmicity: effects of insufficient and mistimed sleep on the animal and human transcriptome.

    PubMed

    Archer, Simon N; Oster, Henrik

    2015-10-01

    The mammalian circadian system is a multi-oscillator, hierarchically organised system where a central pacemaker synchronises behavioural, physiological and gene expression rhythms in peripheral tissues. Epidemiological studies show that disruption of this internal synchronisation by short sleep and shift work is associated with adverse health outcomes through mechanisms that remain to be elucidated. Here, we review recent animal and human studies demonstrating the profound effects of insufficient and mistimed sleep on the rhythms of gene expression in central and peripheral tissues. In mice, sleep restriction leads to an ~80% reduction in circadian transcripts in the brain and profound disruption of the liver transcriptome. In humans, sleep restriction leads to a 1.9% reduction in circadian transcripts in whole blood, and when sleep is displaced to the daytime, 97% of rhythmic genes become arrhythmic and one-third of all genes show changes in temporal expression profiles. These changes in mice and humans include a significant reduction in the circadian regulation of transcription and translation and core clock genes in the periphery, while at the same time rhythms within the suprachiasmatic nucleus are not disrupted. Although the physiological mediators of these sleep disruption effects on the transcriptome have not been established, altered food intake, changes in hormones such as cortisol, and changes in body and brain temperature may play important roles. Processes and molecular pathways associated with these disruptions include metabolism, immune function, inflammatory and stress responses, and point to the molecular mechanisms underlying the established adverse health outcomes associated with short sleep duration and shift work, such as metabolic syndrome and cancer.

  1. Parallel evolution of serotonergic neuromodulation underlies independent evolution of rhythmic motor behavior.

    PubMed

    Lillvis, Joshua L; Katz, Paul S

    2013-02-06

    Neuromodulation can dynamically alter neuronal and synaptic properties, thereby changing the behavioral output of a neural circuit. It is therefore conceivable that natural selection might act upon neuromodulation as a mechanism for sculpting the behavioral repertoire of a species. Here we report that the presence of neuromodulation is correlated with the production of a behavior that most likely evolved independently in two species: Tritonia diomedea and Pleurobranchaea californica (Mollusca, Gastropoda, Opisthobranchia, Nudipleura). Individuals of both species exhibit escape swimming behaviors consisting of repeated dorsal-ventral whole-body flexions. The central pattern generator (CPG) circuits underlying these behaviors contain homologous identified neurons: DSI and C2 in Tritonia and As and A1 in Pleurobranchaea. Homologs of these neurons also can be found in Hermissenda crassicornis where they are named CPT and C2, respectively. However, members of this species do not exhibit an analogous swimming behavior. In Tritonia and Pleurobranchaea, but not in Hermissenda, the serotonergic DSI homologs modulated the strength of synapses made by C2 homologs. Furthermore, the serotonin receptor antagonist methysergide blocked this neuromodulation and the swimming behavior. Additionally, in Pleurobranchaea, the robustness of swimming correlated with the extent of the synaptic modulation. Finally, injection of serotonin induced the swimming behavior in Tritonia and Pleurobranchaea, but not in Hermissenda. This suggests that the analogous swimming behaviors of Tritonia and Pleurobranchaea share a common dependence on serotonergic neuromodulation. Thus, neuromodulation may provide a mechanism that enables species to acquire analogous behaviors independently using homologous neural circuit components.

  2. Innate immune defenses exhibit circadian rhythmicity and differential temporal sensitivity to a bacterial endotoxin in Nile tilapia (Oreochromis niloticus).

    PubMed

    Lazado, Carlo C; Skov, Peter Vilhelm; Pedersen, Per Bovbjerg

    2016-08-01

    The present study investigated the daily dynamics of humoral immune defenses and the temporal influence in the sensitivity of these responses to a bacteria