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Sample records for brain hemodynamic responses

  1. Abnormal hemodynamic response to forepaw stimulation in rat brain after cocaine injection

    Science.gov (United States)

    Chen, Wei; Park, Kicheon; Choi, Jeonghun; Pan, Yingtian; Du, Congwu

    2015-03-01

    Simultaneous measurement of hemodynamics is of great importance to evaluate the brain functional changes induced by brain diseases such as drug addiction. Previously, we developed a multimodal-imaging platform (OFI) which combined laser speckle contrast imaging with multi-wavelength imaging to simultaneously characterize the changes in cerebral blood flow (CBF), oxygenated- and deoxygenated- hemoglobin (HbO and HbR) from animal brain. Recently, we upgraded our OFI system that enables detection of hemodynamic changes in response to forepaw electrical stimulation to study potential brain activity changes elicited by cocaine. The improvement includes 1) high sensitivity to detect the cortical response to single forepaw electrical stimulation; 2) high temporal resolution (i.e., 16Hz/channel) to resolve dynamic variations in drug-delivery study; 3) high spatial resolution to separate the stimulation-evoked hemodynamic changes in vascular compartments from those in tissue. The system was validated by imaging the hemodynamic responses to the forepaw-stimulations in the somatosensory cortex of cocaine-treated rats. The stimulations and acquisitions were conducted every 2min over 40min, i.e., from 10min before (baseline) to 30min after cocaine challenge. Our results show that the HbO response decreased first (at ~4min) followed by the decrease of HbR response (at ~6min) after cocaine, and both did not fully recovered for over 30min. Interestingly, while CBF decreased at 4min, it partially recovered at 18min after cocaine administration. The results indicate the heterogeneity of cocaine's effects on vasculature and tissue metabolism, demonstrating the unique capability of optical imaging for brain functional studies.

  2. Exploring diazepam's effect on hemodynamic responses of mouse brain tissue by optical spectroscopic imaging.

    Science.gov (United States)

    Abookasis, David; Shochat, Ariel; Nesher, Elimelech; Pinhasov, Albert

    2014-07-01

    In this study, a simple duel-optical spectroscopic imaging apparatus capable of simultaneously determining relative changes in brain oxy-and deoxy-hemoglobin concentrations was used following administration of the anxiolytic compound diazepam in mice with strong dominant (Dom) and submissive (Sub) behavioral traits. Three month old mice (n = 30) were anesthetized and after 10 min of baseline imaging, diazepam (1.5 mg/kg) was administered and measurements were taken for 80 min. The mouse head was illuminated by white light based LED's and diffused reflected light passing through different channels, consisting of a bandpass filter and a CCD camera, respectively, was collected and analyzed to measure the hemodynamic response. This work's major findings are threefold: first, Dom and Sub animals showed statistically significant differences in hemodynamic response to diazepam administration. Secondly, diazepam was found to more strongly affect the Sub group. Thirdly, different time-series profiles were observed post-injection, which can serve as a possible marker for the groups' differentiation. To the best of our knowledge, this is the first report on the effects of an anxiolytic drug on brain hemodynamic responses in mice using diffused light optical imaging. PMID:25071958

  3. CMOS Image Sensor and System for Imaging Hemodynamic Changes in Response to Deep Brain Stimulation.

    Science.gov (United States)

    Zhang, Xiao; Noor, Muhammad S; McCracken, Clinton B; Kiss, Zelma H T; Yadid-Pecht, Orly; Murari, Kartikeya

    2016-06-01

    Deep brain stimulation (DBS) is a therapeutic intervention used for a variety of neurological and psychiatric disorders, but its mechanism of action is not well understood. It is known that DBS modulates neural activity which changes metabolic demands and thus the cerebral circulation state. However, it is unclear whether there are correlations between electrophysiological, hemodynamic and behavioral changes and whether they have any implications for clinical benefits. In order to investigate these questions, we present a miniaturized system for spectroscopic imaging of brain hemodynamics. The system consists of a 144 ×144, [Formula: see text] pixel pitch, high-sensitivity, analog-output CMOS imager fabricated in a standard 0.35 μm CMOS process, along with a miniaturized imaging system comprising illumination, focusing, analog-to-digital conversion and μSD card based data storage. This enables stand alone operation without a computer, nor electrical or fiberoptic tethers. To achieve high sensitivity, the pixel uses a capacitive transimpedance amplifier (CTIA). The nMOS transistors are in the pixel while pMOS transistors are column-parallel, resulting in a fill factor (FF) of 26%. Running at 60 fps and exposed to 470 nm light, the CMOS imager has a minimum detectable intensity of 2.3 nW/cm(2) , a maximum signal-to-noise ratio (SNR) of 49 dB at 2.45 μW/cm(2) leading to a dynamic range (DR) of 61 dB while consuming 167 μA from a 3.3 V supply. In anesthetized rats, the system was able to detect temporal, spatial and spectral hemodynamic changes in response to DBS. PMID:26357405

  4. Hemodynamic response imaging: a potential tool for the assessment of angiogenesis in brain tumors.

    Directory of Open Access Journals (Sweden)

    Dafna Ben Bashat

    Full Text Available Blood oxygenation level dependence (BOLD imaging under either hypercapnia or hyperoxia has been used to study neuronal activation and for assessment of various brain pathologies. We evaluated the benefit of a combined protocol of BOLD imaging during both hyperoxic and hypercapnic challenges (termed hemodynamic response imaging (HRI. Nineteen healthy controls and seven patients with primary brain tumors were included: six with glioblastoma (two newly diagnosed and four with recurrent tumors and one with atypical-meningioma. Maps of percent signal intensity changes (ΔS during hyperoxia (carbogen; 95%O2+5%CO2 and hypercapnia (95%air+5%CO2 challenges and vascular reactivity mismatch maps (VRM; voxels that responded to carbogen with reduced/absent response to CO2 were calculated. VRM values were measured in white matter (WM and gray matter (GM areas of healthy subjects and used as threshold values in patients. Significantly higher response to carbogen was detected in healthy subjects, compared to hypercapnia, with a GM/WM ratio of 3.8 during both challenges. In patients with newly diagnosed/treatment-naive tumors (n = 3, increased response to carbogen was detected with substantially increased VRM response (compared to threshold values within and around the tumors. In patients with recurrent tumors, reduced/absent response during both challenges was demonstrated. An additional finding in 2 of 4 patients with recurrent glioblastoma was a negative response during carbogen, distant from tumor location, which may indicate steal effect. In conclusion, the HRI method enables the assessment of blood vessel functionality and reactivity. Reference values from healthy subjects are presented and preliminary results demonstrate the potential of this method to complement perfusion imaging for the detection and follow up of angiogenesis in patients with brain tumors.

  5. Implantable self-reset CMOS image sensor and its application to hemodynamic response detection in living mouse brain

    Science.gov (United States)

    Yamaguchi, Takahiro; Takehara, Hiroaki; Sunaga, Yoshinori; Haruta, Makito; Motoyama, Mayumi; Ohta, Yasumi; Noda, Toshihiko; Sasagawa, Kiyotaka; Tokuda, Takashi; Ohta, Jun

    2016-04-01

    A self-reset pixel of 15 × 15 µm2 with high signal-to-noise ratio (effective peak SNR ≃64 dB) for an implantable image sensor has been developed for intrinsic signal detection arising from hemodynamic responses in a living mouse brain. For detecting local conversion between oxyhemoglobin (HbO) and deoxyhemoglobin (HbR) in brain tissues, an implantable imaging device was fabricated with our newly designed self-reset image sensor and orange light-emitting diodes (LEDs; λ = 605 nm). We demonstrated imaging of hemodynamic responses in the sensory cortical area accompanied by forelimb stimulation of a living mouse. The implantable imaging device for intrinsic signal detection is expected to be a powerful tool to measure brain activities in living animals used in behavioral analysis.

  6. Re-examine tumor-induced alterations in hemodynamic responses of BOLD fMRI. Implications in presurgical brain mapping

    International Nuclear Information System (INIS)

    Background: Blood oxygenation level dependent (BOLD) fMRI is used for presurgical functional mapping of brain tumor patients. Abnormal tumor blood supply may affect hemodynamic responses and BOLD fMRI signals. Purpose: To perform a multivariate and quantitative investigation of the effect of brain tumors on the hemodynamic responses and its impact on BOLD MRI signal time course, data analysis in order to better understand tumor-induced alterations in hemodynamic responses, and accurately mapping cortical regions in brain tumor patients. Material and Methods: BOLD fMRI data from 42 glioma patients who underwent presurgical mapping of the primary motor cortex (PMC) with a block designed finger tapping paradigm were analyzed, retrospectively. Cases were divided into high grade (n = 24) and low grade (n = 18) groups based on pathology. The tumor volume and distance to the activated PMCs were measured. BOLD signal time courses from selected regions of interest (ROIs) in the PMCs of tumor affected and contralateral unaffected hemispheres were obtained from each patient. Tumor-induced changes of BOLD signal intensity and time to peak (TTP) of BOLD signal time courses were analyzed statistically. Results: The BOLD signal intensity and TTP in the tumor-affected PMCs are altered when compared to that of the unaffected hemisphere. The average BOLD signal level is statistically significant lower in the affected PMCs. The average TTP in the affected PMCs is shorter in the high grade group, but longer in the low grade tumor group compared to the contralateral unaffected hemisphere. Degrees of alterations in BOLD signal time courses are related to both the distance to activated foci and tumor volume with the stronger effect in tumor distance to activated PMC. Conclusion: Alterations in BOLD signal time courses are strongly related to the tumor grade, the tumor volume, and the distance to the activated foci. Such alterations may impair accurate mapping of tumor-affected functional

  7. Measuring brain hemodynamic changes in a songbird: responses to hypercapnia measured with functional MRI and near-infrared spectroscopy

    Science.gov (United States)

    Vignal, C.; Boumans, T.; Montcel, B.; Ramstein, S.; Verhoye, M.; Van Audekerke, J.; Mathevon, N.; Van der Linden, A.; Mottin, S.

    2008-05-01

    Songbirds have been evolved into models of choice for the study of the cerebral underpinnings of vocal communication. Nevertheless, there is still a need for in vivo methods allowing the real-time monitoring of brain activity. Functional Magnetic Resonance Imaging (fMRI) has been applied in anesthetized intact songbirds. It relies on blood oxygen level-dependent (BOLD) contrast revealing hemodynamic changes. Non-invasive near-infrared spectroscopy (NIRS) is based on the weak absorption of near-infrared light by biological tissues. Time-resolved femtosecond white laser NIRS is a new probing method using real-time spectral measurements which give access to the local variation of absorbing chromophores such as hemoglobins. In this study, we test the efficiency of our time-resolved NIRS device in monitoring physiological hemodynamic brain responses in a songbird, the zebra finch (Taeniopygia guttata), using a hypercapnia event (7% inhaled CO2). The results are compared to those obtained using BOLD fMRI. The NIRS measurements clearly demonstrate that during hypercapnia the blood oxygen saturation level increases (increase in local concentration of oxyhemoglobin, decrease in deoxyhemoglobin concentration and total hemoglobin concentration). Our results provide the first correlation in songbirds of the variations in total hemoglobin and oxygen saturation level obtained from NIRS with local BOLD signal variations.

  8. Measuring brain hemodynamic changes in a songbird: responses to hypercapnia measured with functional MRI and near-infrared spectroscopy

    International Nuclear Information System (INIS)

    Songbirds have been evolved into models of choice for the study of the cerebral underpinnings of vocal communication. Nevertheless, there is still a need for in vivo methods allowing the real-time monitoring of brain activity. Functional Magnetic Resonance Imaging (fMRI) has been applied in anesthetized intact songbirds. It relies on blood oxygen level-dependent (BOLD) contrast revealing hemodynamic changes. Non-invasive near-infrared spectroscopy (NIRS) is based on the weak absorption of near-infrared light by biological tissues. Time-resolved femtosecond white laser NIRS is a new probing method using real-time spectral measurements which give access to the local variation of absorbing chromophores such as hemoglobins. In this study, we test the efficiency of our time-resolved NIRS device in monitoring physiological hemodynamic brain responses in a songbird, the zebra finch (Taeniopygia guttata), using a hypercapnia event (7% inhaled CO2). The results are compared to those obtained using BOLD fMRI. The NIRS measurements clearly demonstrate that during hypercapnia the blood oxygen saturation level increases (increase in local concentration of oxyhemoglobin, decrease in deoxyhemoglobin concentration and total hemoglobin concentration). Our results provide the first correlation in songbirds of the variations in total hemoglobin and oxygen saturation level obtained from NIRS with local BOLD signal variations

  9. Measuring brain hemodynamic changes in a songbird: responses to hypercapnia measured with functional MRI and near-infrared spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Vignal, C; Mathevon, N [ENES EA 3988, Universite Jean Monnet, Saint-Etienne (France); Boumans, T; Verhoye, M; Audekerke, J van; Linden, A van der [Bio-Imaging Laboratory, University of Antwerp, Antwerp (Belgium); Montcel, B; Ramstein, S; Mottin, S [Hubert Curien CNRS UMR 5516, Universite Jean Monnet, Saint-Etienne (France)], E-mail: Clementine.Vignal@univ-st-etienne.fr

    2008-05-21

    Songbirds have been evolved into models of choice for the study of the cerebral underpinnings of vocal communication. Nevertheless, there is still a need for in vivo methods allowing the real-time monitoring of brain activity. Functional Magnetic Resonance Imaging (fMRI) has been applied in anesthetized intact songbirds. It relies on blood oxygen level-dependent (BOLD) contrast revealing hemodynamic changes. Non-invasive near-infrared spectroscopy (NIRS) is based on the weak absorption of near-infrared light by biological tissues. Time-resolved femtosecond white laser NIRS is a new probing method using real-time spectral measurements which give access to the local variation of absorbing chromophores such as hemoglobins. In this study, we test the efficiency of our time-resolved NIRS device in monitoring physiological hemodynamic brain responses in a songbird, the zebra finch (Taeniopygia guttata), using a hypercapnia event (7% inhaled CO{sub 2}). The results are compared to those obtained using BOLD fMRI. The NIRS measurements clearly demonstrate that during hypercapnia the blood oxygen saturation level increases (increase in local concentration of oxyhemoglobin, decrease in deoxyhemoglobin concentration and total hemoglobin concentration). Our results provide the first correlation in songbirds of the variations in total hemoglobin and oxygen saturation level obtained from NIRS with local BOLD signal variations.

  10. Dual-wavelength laser speckle imaging for monitoring brain metabolic and hemodynamic response to closed head traumatic brain injury in mice

    Science.gov (United States)

    Kofman, Itamar; Abookasis, David

    2015-10-01

    ) monitor brain hemodynamic and metabolic response to neuroprotective drug treatment.

  11. Hemodynamic findings in patients with brain stroke

    OpenAIRE

    Siebert, Janusz; Gutknecht, Piotr; Molisz, Andrzej; Trzeciak, Bartosz; Nyka, Walenty

    2012-01-01

    Introduction Standard procedures carried out at a stroke department in patients after a cerebral event may prove insufficient for monitoring hemodynamic indices. Impedance cardiography enables hemodynamic changes to be monitored non-invasively. The aim of the work was to describe hemodynamic parameters in patients with acute phase of ischemic and hemorrhagic stroke and to analyse the correlation between the type of hemodynamic response and long-term prognosis. Material and methods The 45 cons...

  12. Assessment of sexual orientation using the hemodynamic brain response to visual sexual stimuli

    DEFF Research Database (Denmark)

    Ponseti, Jorge; Granert, Oliver; Jansen, Olav;

    2009-01-01

    reliability. AIM: To evaluate whether the spatial response pattern to sexual stimuli as revealed by a change in blood oxygen level-dependent (BOLD) signal can be used for individual classification of sexual orientation. METHODS: We used a preexisting functional MRI (fMRI) data set that had been acquired in a...... nonclinical sample of 12 heterosexual men and 14 homosexual men. During fMRI, participants were briefly exposed to pictures of same-sex and opposite-sex genitals. Data analysis involved four steps: (i) differences in the BOLD response to female and male sexual stimuli were calculated for each subject; (ii......) these contrast images were entered into a group analysis to calculate whole-brain difference maps between homosexual and heterosexual participants; (iii) a single expression value was computed for each subject expressing its correspondence to the group result; and (iv) based on these expression values...

  13. Neuronal inhibition and excitation, and the dichotomic control of brain hemodynamic and oxygen responses

    DEFF Research Database (Denmark)

    Lauritzen, Martin; Mathiesen, Claus; Schaefer, Katharina;

    2012-01-01

    Brain's electrical activity correlates strongly to changes in cerebral blood flow (CBF) and the cerebral metabolic rate of oxygen (CMRO(2)). Subthreshold synaptic processes correlate better than the spike rates of principal neurons to CBF, CMRO(2) and positive BOLD signals. Stimulation...... metabolic and vascular control explains the gap between the stimulation-induced rises in CMRO(2) and CBF, and in turn the BOLD signal. Activity-dependent rises in CBF and CMRO(2) vary within and between brain regions due to differences in ATP turnover and Ca(2+)-dependent mechanisms. Nerve cells produce and...... release vasodilators that evoke positive BOLD signals, while the mechanisms that control negative BOLD signals by activity-dependent vasoconstriction are less well understood. Activation of both excitatory and inhibitory neurons produces rises in CBF and positive BOLD signals, while negative BOLD signals...

  14. Microstructural Brain Differences Predict Functional Hemodynamic Responses in a Reward Processing Task

    OpenAIRE

    Càmara, E.; Rodríguez Fornells, Antoni; Münte, Thomas F.

    2010-01-01

    Many aspects of human behavior are driven by rewards, yet different people are differentially sensitive to rewards and punishment. In this study, we showthat white matter microstructure inthe uncinate/inferiorfronto-occipitalfasciculus, defined byfractional anisotropy values derived from diffusion tensor magnetic resonance images, correlates with both short-term (indexed by the fMRI blood oxygenation level-dependent response to reward in the nucleus accumbens) and long-term (indexed by the tr...

  15. Microstructural brain differences predict functional hemodynamic responses in a reward processing task.

    Science.gov (United States)

    Camara, Estela; Rodriguez-Fornells, Antoni; Münte, Thomas F

    2010-08-25

    Many aspects of human behavior are driven by rewards, yet different people are differentially sensitive to rewards and punishment. In this study, we show that white matter microstructure in the uncinate/inferior fronto-occipital fasciculus, defined by fractional anisotropy values derived from diffusion tensor magnetic resonance images, correlates with both short-term (indexed by the fMRI blood oxygenation level-dependent response to reward in the nucleus accumbens) and long-term (indexed by the trait measure sensitivity to punishment) reactivity to rewards. Moreover, trait measures of reward processing were also correlated with reward-related functional activation in the nucleus accumbens. The white matter tract revealed by the correlational analysis connects the anterior temporal lobe with the medial and lateral orbitofrontal cortex and also supplies the ventral striatum. The pattern of strong correlations suggests an intimate relationship between white matter structure and reward-related behavior that may also play a role in a number of pathological conditions, such as addiction and pathological gambling. PMID:20739561

  16. Effect of an inhibitor of neuronal nitric oxide synthase 7-nitroindazole on cerebral hemodynamic response and brain excitability in urethane-anesthetized rats

    Czech Academy of Sciences Publication Activity Database

    Brožíčková, Carole; Otáhal, Jakub

    2013-01-01

    Roč. 62, Suppl.1 (2013), S57-S66. ISSN 0862-8408 R&D Projects: GA ČR(CZ) GAP303/10/0999; GA ČR(CZ) GPP304/11/P386; GA ČR(CZ) GBP304/12/G069 Institutional research plan: CEZ:AV0Z50110509 Institutional support: RVO:67985823 Keywords : cerebral hemodynamic response * brain excitability * neuronal nitric oxide synthase * 7-nitroindazole * rat Subject RIV: FH - Neurology Impact factor: 1.487, year: 2013

  17. Causal connectivity alterations of cortical-subcortical circuit anchored on reduced hemodynamic response brain regions in first-episode drug-naïve major depressive disorder.

    Science.gov (United States)

    Gao, Qing; Zou, Ke; He, Zongling; Sun, Xueli; Chen, Huafu

    2016-01-01

    Some efforts were done to investigate the disruption of brain causal connectivity networks involved in major depressive disorder (MDD) using Granger causality (GC) analysis. However, the homogenous hemodynamic response function (HRF) assumption over the brain may disturb the inference of temporal precedence. Here we applied a blind deconvolution approach to examine the altered HRF shape in first-episode, drug-naïve MDD patients. The regions with abnormal HRF shape in patients were chosen as seeds to detect the GC alterations in MDD. The results demonstrated significantly decreased magnitude of spontaneous hemodynamic response of the orbital frontal cortex (OFC) and the caudate nucleus (CAU) in MDD comparing to healthy controls, suggesting MDD patients likely had alterations in neurovascular coupling and cerebrovascular physiology in these two regions. GC mapping showed increased/decreased GC in OFC-/CAU centered networks in MDD. The outgoing GC values from OFC to anterior cingulate cortex and occipital regions were positively correlated with Hamilton Depression Scale (HAMD) scores, while the incoming GC from insula, middle and superior temporal gyrus to CAU were negatively correlated with HAMD scores of MDD. The abnormalities of directional connections in the cortico-subcortico-cerebellar network may lead to unbalanced integrating the emotional-related information for MDD, and further exacerbating depressive symptoms. PMID:26911651

  18. Inter-subject correlation of brain hemodynamic responses during watching a movie: localization in space and frequency

    Directory of Open Access Journals (Sweden)

    Jukka-Pekka Kauppi

    2010-03-01

    Full Text Available Cinema is a promising naturalistic stimulus that enables, for instance, elicitation of robust emotions during functional magnetic resonance imaging (fMRI. Inter-subject correlation (ISC has been used as a model-free analysis method to map the highly complex hemodynamic responses that are evoked during watching a movie. Here, we extended the ISC analysis to frequency domain using wavelet analysis combined with non-parametric permutation methods for making voxel-wise statistical inferences about frequency-band specific ISC. We applied these novel analysis methods to a dataset collected in our previous study where 12 subjects watched an emotionally engaging movie “Crash” during fMRI scanning. Our results suggest that several regions within the frontal and temporal lobes show ISC predominantly at low frequency bands, whereas visual cortical areas exhibit ISC also at higher frequencies. It is possible that these findings relate to recent observations of a cortical hierarchy of temporal receptive windows, or that the types of events processed in temporal and prefrontal cortical areas (e.g., social interactions occur over longer time periods than the stimulus features processed in the visual areas. Software tools to perform frequency-specific ISC analysis, together with a visualization application, are available as open source Matlab code.

  19. Optical imaging of neural and hemodynamic brain activity

    Science.gov (United States)

    Schei, Jennifer Lynn

    Optical imaging technologies can be used to record neural and hemodynamic activity. Neural activity elicits physiological changes that alter the optical tissue properties. Specifically, changes in polarized light are concomitant with neural depolarization. We measured polarization changes from an isolated lobster nerve during action potential propagation using both reflected and transmitted light. In transmission mode, polarization changes were largest throughout the center of the nerve, suggesting that most of the optical signal arose from the inner nerve bundle. In reflection mode, polarization changes were largest near the edges, suggesting that most of the optical signal arose from the outer sheath. To overcome irregular cell orientation found in the brain, we measured polarization changes from a nerve tied in a knot. Our results show that neural activation produces polarization changes that can be imaged even without regular cell orientations. Neural activation expends energy resources and elicits metabolic delivery through blood vessel dilation, increasing blood flow and volume. We used spectroscopic imaging techniques combined with electrophysiological measurements to record evoked neural and hemodynamic responses from the auditory cortex of the rat. By using implantable optics, we measured responses across natural wake and sleep states, as well as responses following different amounts of sleep deprivation. During quiet sleep, evoked metabolic responses were larger compared to wake, perhaps because blood vessels were more compliant. When animals were sleep deprived, evoked hemodynamic responses were smaller following longer periods of deprivation. These results suggest that prolonged neural activity through sleep deprivation may diminish vascular compliance as indicated by the blunted vascular response. Subsequent sleep may allow vessels to relax, restoring their ability to deliver blood. These results also suggest that severe sleep deprivation or chronic

  20. Esmolol vs. nitroglycerin: attenuating hemodynamic response to laryngoscopy and intubation

    Directory of Open Access Journals (Sweden)

    Cassie Held

    2016-01-01

    Full Text Available Hemodynamic response to laryngoscopy and intubation is a common occurrence with the potential for harmful effects. Many drugs have been utilized throughout the years to attenuate this response with mixed results. This review compares the efficacy of two drugs, esmolol and nitroglycerin, in attenuating hemodynamic response to laryngoscopy and intubation. A systematic review was performed compiling all previous studies detailing the efficacy of esmolol in comparison to nitroglycerin for this purpose. Esmolol was found to consistently attenuate hemodynamic responses of blood pressure and heart rate with greater efficacy than nitroglycerin, and is thus recommended over nitroglycerin for use in this role.

  1. Self-reported tolerance influences prefrontal cortex hemodynamics and affective responses.

    Science.gov (United States)

    Tempest, Gavin; Parfitt, Gaynor

    2016-02-01

    The relationship between cognitive and sensory processes in the brain contributes to the regulation of affective responses (pleasure-displeasure). Exercise can be used to manipulate sensory processes (by increasing physiological demand) in order to examine the role of dispositional traits that may influence an individual's ability to cognitively regulate these responses. With the use of near infrared spectroscopy, in this study we examined the influence of self-reported tolerance upon prefrontal cortex (PFC) hemodynamics and affective responses. The hemodynamic response was measured in individuals with high or low tolerance during an incremental exercise test. Sensory manipulation was standardized against metabolic processes (ventilatory threshold [VT] and respiratory compensation point [RCP]), and affective responses were recorded. The results showed that the high-tolerance group displayed a larger hemodynamic response within the right PFC above VT (which increased above RCP). The low-tolerance group showed a larger hemodynamic response within the left PFC above VT. The high-tolerance group reported a more positive/less negative affective response above VT. These findings provide direct neurophysiological evidence of differential hemodynamic responses within the PFC that are associated with tolerance in the presence of increased physiological demands. This study supports the role of dispositional traits and previous theorizing into the underlying mechanisms (cognitive vs. sensory processes) of affective responses. PMID:26337703

  2. Esmolol vs. nitroglycerin: attenuating hemodynamic response to laryngoscopy and intubation

    OpenAIRE

    Cassie Held

    2016-01-01

    Hemodynamic response to laryngoscopy and intubation is a common occurrence with the potential for harmful effects. Many drugs have been utilized throughout the years to attenuate this response with mixed results. This review compares the efficacy of two drugs, esmolol and nitroglycerin, in attenuating hemodynamic response to laryngoscopy and intubation. A systematic review was performed compiling all previous studies detailing the efficacy of esmolol in comparison to nitroglycerin for this pu...

  3. Hemodynamic Response Alteration As a Function of Task Complexity and Expertise—An fNIRS Study in Jugglers

    OpenAIRE

    Carius, Daniel; Andrä, Christian; Clauß, Martina; Ragert, Patrick; Bunk, Michael; Mehnert, Jan

    2016-01-01

    Detailed knowledge about online brain processing during the execution of complex motor tasks with a high motion range still remains elusive. The aim of the present study was to investigate the hemodynamic responses within sensorimotor networks as well as in visual motion area during the execution of a complex visuomotor task such as juggling. More specifically, we were interested in how far the hemodynamic response as measured with functional near infrared spectroscopy (fNIRS) adapts as a fun...

  4. Optogenetic fMRI in the mouse hippocampus: Hemodynamic response to brief glutamatergic stimuli.

    Science.gov (United States)

    Lebhardt, Philipp; Hohenberg, Christian Clemm von; Weber-Fahr, Wolfgang; Kelsch, Wolfgang; Sartorius, Alexander

    2016-03-01

    The combination of optogenetics with functional magnetic resonance imaging is a promising tool to study the causal relationship between specific neuronal populations and global brain activity. We employed this technique to study the brain response to recruitment of glutamatergic neurons in the mouse hippocampus. The light-sensitive protein channelrhodopsin-2 was expressed in α-CamKII-positive glutamatergic neurons in the left hippocampus (N = 10). Functional magnetic resonance imaging was performed during local laser stimulation, with stimulus duration of 1 second. The hemodynamic response to these stimuli was analyzed on a whole-brain level. In a secondary analysis, we examined the impact of the stimulation locus on the dorso-ventral axis within the hippocampal formation. The hemodynamic response in the mouse hippocampus had an earlier peak and a shorter duration compared to those observed in humans. Photostimulation was associated with significantly increased blood oxygen level-dependent signal in group statistics: bilaterally in the hippocampus, frontal lobe and septum, ipsilaterally in the nucleus accumbens and contralaterally in the striatum. More dorsal position of the laser fiber was associated with a stronger activation in projection regions (insular cortex and striatum). The characterization of brain-region-specific hemodynamic response functions may enable more precise interpretation of future functional magnetic resonance imaging experiments. PMID:26661158

  5. Hemodynamic responses to speech and music in preverbal infants.

    Science.gov (United States)

    Fava, Eswen; Hull, Rachel; Baumbauer, Kyle; Bortfeld, Heather

    2014-01-01

    Numerous studies have provided clues about the ontogeny of lateralization of auditory processing in humans, but most have employed specific subtypes of stimuli and/or have assessed responses in discrete temporal windows. The present study used near-infrared spectroscopy (NIRS) to establish changes in hemodynamic activity in the neocortex of preverbal infants (aged 4-11 months) while they were exposed to two distinct types of complex auditory stimuli (full sentences and musical phrases). Measurements were taken from bilateral temporal regions, including both anterior and posterior superior temporal gyri. When the infant sample was treated as a homogenous group, no significant effects emerged for stimulus type. However, when infants' hemodynamic responses were categorized according to their overall changes in volume, two very clear neurophysiological patterns emerged. A high-responder group showed a pattern of early and increasing activation, primarily in the left hemisphere, similar to that observed in comparable studies with adults. In contrast, a low-responder group showed a pattern of gradual decreases in activation over time. Although age did track with responder type, no significant differences between these groups emerged for stimulus type, suggesting that the high- versus low-responder characterization generalizes across classes of auditory stimuli. These results highlight a new way to conceptualize the variable cortical blood flow patterns that are frequently observed across infants and stimuli, with hemodynamic response volumes potentially serving as an early indicator of developmental changes in auditory-processing sensitivity. PMID:23777481

  6. Hemodynamic Responses to Head and Neck Cooling

    Science.gov (United States)

    Ku, Yu-Tsuan E.; Carbo, Jorge E.; Montgomery, Leslie D.; Webbon, Bruce W.

    1994-01-01

    Personal thermoregulatory systems which provide head and neck cooling are used in the industrial and aerospace environments to alleviate thermal stress. However, little information is available regarding the physiologic and circulatory changes produced by routine operation of these systems. The objective of this study was to measure the scalp temperature and circulatory responses during use of one commercially available thermal control system. The Life Support Systems, Inc. Mark VII portable cooling system and a liquid cooling helmet were used in this study. Two EEG electrodes and one skin temperature transducer were placed on the anterior midline of the scalp to measure the scalp blood and temperature. Blood flow was measured using a bipolar impedance rheograph. Ten subjects, seated in an upright position at normal room temperature, were tested at high, medium, moderate, moderate-low and low coolant temperatures. Scalp blood flow was recorded continuously using a computer data acquisition system with a sampling frequency of 200 Hz. Scalp temperature and cooling helmet Inlet temperature was logged periodically during the test period. This study quantifies the effect of head cooling upon scalp temperature and blood flow. These data may also be used to select operational specifications of the head cooling system for biomedical applications such as the treatment of migraine headaches, scalp cooling during chemotherapy, and cooling of multiple sclerosis patients.

  7. Hemodynamic response alteration as a function of task complexity and expertise - An fNIRS study in jugglers

    Directory of Open Access Journals (Sweden)

    Daniel eCarius

    2016-03-01

    Full Text Available Detailed knowledge about online brain processing during the execution of complex motor tasks with a high motion range still remains elusive. The aim of the present study was to investigate the hemodynamic responses within sensorimotor networks as well as in visual motion area during the execution of a complex visuomotor task such as juggling. More specifically, we were interested in how far the hemodynamic response as measured with functional near infrared spectroscopy (fNIRS adapts as a function of task complexity and the level of the juggling expertise. We asked expert jugglers to perform different juggling tasks with different levels of complexity such as a 2-ball juggling, 3- and 5-ball juggling cascades. We here demonstrate that expert jugglers show an altered neurovascular response with increasing task complexity, since a 5-ball juggling cascade showed enhanced hemodynamic responses for oxy-Hb as compared to less complex tasks such as a 3- or 2- ball juggling pattern. Moreover, correlations between the hemodynamic response and the level of the juggling expertise during the 5-ball juggling cascade, acquired by cinematographic video analysis, revealed only a non-significant trend in M1, indicating that a higher level of expertise might be associated with lower hemodynamic responses.

  8. Hemodynamic Response Alteration As a Function of Task Complexity and Expertise-An fNIRS Study in Jugglers.

    Science.gov (United States)

    Carius, Daniel; Andrä, Christian; Clauß, Martina; Ragert, Patrick; Bunk, Michael; Mehnert, Jan

    2016-01-01

    Detailed knowledge about online brain processing during the execution of complex motor tasks with a high motion range still remains elusive. The aim of the present study was to investigate the hemodynamic responses within sensorimotor networks as well as in visual motion area during the execution of a complex visuomotor task such as juggling. More specifically, we were interested in how far the hemodynamic response as measured with functional near infrared spectroscopy (fNIRS) adapts as a function of task complexity and the level of the juggling expertise. We asked expert jugglers to perform different juggling tasks with different levels of complexity such as a 2-ball juggling, 3- and 5-ball juggling cascades. We here demonstrate that expert jugglers show an altered neurovascular response with increasing task complexity, since a 5-ball juggling cascade showed enhanced hemodynamic responses for oxygenated hemoglobin as compared to less complex tasks such as a 3- or 2-ball juggling pattern. Moreover, correlations between the hemodynamic response and the level of the juggling expertise during the 5-ball juggling cascade, acquired by cinematographic video analysis, revealed only a non-significant trend in primary motor cortex, indicating that a higher level of expertise might be associated with lower hemodynamic responses. PMID:27064925

  9. Hemodynamic Response Alteration As a Function of Task Complexity and Expertise—An fNIRS Study in Jugglers

    Science.gov (United States)

    Carius, Daniel; Andrä, Christian; Clauß, Martina; Ragert, Patrick; Bunk, Michael; Mehnert, Jan

    2016-01-01

    Detailed knowledge about online brain processing during the execution of complex motor tasks with a high motion range still remains elusive. The aim of the present study was to investigate the hemodynamic responses within sensorimotor networks as well as in visual motion area during the execution of a complex visuomotor task such as juggling. More specifically, we were interested in how far the hemodynamic response as measured with functional near infrared spectroscopy (fNIRS) adapts as a function of task complexity and the level of the juggling expertise. We asked expert jugglers to perform different juggling tasks with different levels of complexity such as a 2-ball juggling, 3- and 5-ball juggling cascades. We here demonstrate that expert jugglers show an altered neurovascular response with increasing task complexity, since a 5-ball juggling cascade showed enhanced hemodynamic responses for oxygenated hemoglobin as compared to less complex tasks such as a 3- or 2-ball juggling pattern. Moreover, correlations between the hemodynamic response and the level of the juggling expertise during the 5-ball juggling cascade, acquired by cinematographic video analysis, revealed only a non-significant trend in primary motor cortex, indicating that a higher level of expertise might be associated with lower hemodynamic responses. PMID:27064925

  10. [Hemodynamic response to cotton allergen exposure in the industrial environment].

    Science.gov (United States)

    Bakuleva, N S; Usol'tsev, B G; Orlova, O A

    1983-03-01

    The methods of functional diagnosis (mechanocardiography, rheoencephalography) were used to examine the responses of the central and craniocerebral hemodynamics to inhalations of specific cotton allergens in female workers of a textile factory with different grades of sensitization. It was discovered that both the initial level and response pattern on the part of the cardiovascular system and craniocerebral circulation depend to a certain measure on the level of background reactivity. The data obtained enable prognosing the status of the cardiovascular system and taking measures aimed at its correction in subjects sensitized to cotton dust, who continue working in cotton industry. PMID:6830989

  11. Multi-parametric imaging of cerebral hemodynamic and metabolic response followed by ischemic injury

    Science.gov (United States)

    Qin, Jia; Shi, Lei; Dziennis, Suzan; Wang, Ruikang K.

    2014-02-01

    We use rodent parietal cortex as a model system and utilize a synchronized dual wavelength laser speckle imaging (SDW-LSCI) technique to explore the hemodynamic response of infarct and penumbra to a brain injury (middle cerebral artery occlusion (MCAO) model). The SDW-LSCI system is able to take snapshots rapidly (maximum 500 Hz) over the entire brain surface, providing key information about the hemodynamic response, in terms of which it may be used to elucidate evolution of penumbra region from onsite to 90 min of MCAO. Changes in flow are quantified as to the flow experiencing physical occlusions of the MCA normalized to that of baseline. Furthermore, the system is capable of providing information as to the changes of the concentration of oxygenated, (HbO) deoxygenated (Hb), and total hemoglobin (HbT) in the cortex based on the spectral characteristics of HbO and Hb. We observe that the oxygenation variations in the four regions are detectable and distinct. Combining the useful information, four regions of interest (ROI), infarct, penumbra, reduced flow and contralateral portions in the brain upon ischemic injury may be differentiated. Implications of our results are discussed with respect to current understanding of the mechanisms underlying MCAO. We anticipate that SDW-LSCI holds promise for rapid and large field of view localization of ischemic injury.

  12. Hemodynamic responses to orotracheal intubation with a video laryngoscope

    Directory of Open Access Journals (Sweden)

    Shahnaz Shayeghi

    2007-10-01

    Full Text Available Background: Differences in airway anatomy make the potential for technical airway difficulties greater in infants than in
    teenagers or adults. Endotracheal intubation by direct vision using a laryngoscope is frequently associated with an increase
    in arterial blood pressure and heart rate. In different studies, the time to intubation with a video laryngoscope was
    longer than with direct laryngoscopy using Macintosh, and this longer duration may be accompanied by more hemodynamic
    responses.
    METHODS: Sixty-four infants who were scheduled for elective surgery requiring general anesthesia with orotracheal
    intubation were randomly assigned to intubation by direct laryngoscopy using a Macintosh size 1 blade or to intubation
    using a video laryngoscope. Systolic and diastolic blood pressures, heart rate and oxygen saturation were recorded at the
    following time points: (1 before induction, (2 after induction and before intubation, and (3 1 minute and (4 5 minutes
    after intubation.
    RESULTS: No significant differences were found either between the two groups or among the different study periods.
    The duration for laryngoscopy and intubation with a video laryngoscope was 20.87 ± 7.95 seconds (mean ± standard
    deviation and that with Macintosh was 15.41 ± 4.1 seconds (P < 0.01.
    CONCLUSIONS: Similar hemodynamic responses in both groups suggest that laryngoscopy and intubation with a video
    laryngoscope, although with longer duration and therefore resulting in more stimulation, has no significant effect on
    hemodynamic status and oxygen saturation in infants.
    KEY WORDS: Video laryngoscope, laryngoscopy, blood pressure, heart rate

  13. Ischemic preconditioning reduces hemodynamic response during metaboreflex activation.

    Science.gov (United States)

    Mulliri, Gabriele; Sainas, Gianmarco; Magnani, Sara; Palazzolo, Girolamo; Milia, Nicola; Orrù, Andrea; Roberto, Silvana; Marongiu, Elisabetta; Milia, Raffaele; Crisafulli, Antonio

    2016-05-01

    Ischemic preconditioning (IP) has been shown to improve exercise performance and to delay fatigue. However, the precise mechanisms through which IP operates remain elusive. It has been hypothesized that IP lowers the sensation of fatigue by reducing the discharge of group III and IV nerve endings, which also regulate hemodynamics during the metaboreflex. We hypothesized that IP reduces the blood pressure response during the metaboreflex. Fourteen healthy males (age between 25 and 48 yr) participated in this study. They underwent the following randomly assigned protocol: postexercise muscle ischemia (PEMI) test, during which the metaboreflex was elicited after dynamic handgrip; control exercise recovery session (CER) test; and PEMI after IP (IP-PEMI) test. IP was obtained by occluding forearm circulation for three cycles of 5 min spaced by 5 min of reperfusion. Hemodynamics were evaluated by echocardiography and impedance cardiography. The main results were that after IP the mean arterial pressure response was reduced compared with the PEMI test (means ± SD +3.37 ± 6.41 vs. +9.16 ± 7.09 mmHg, respectively). This was the consequence of an impaired venous return that impaired the stroke volume during the IP-PEMI more than during the PEMI test (-1.43 ± 15.35 vs. +10.28 ± 10.479 ml, respectively). It was concluded that during the metaboreflex, IP affects hemodynamics mainly because it impairs the capacity to augment venous return and to recruit the cardiac preload reserve. It was hypothesized that this is the consequence of an increased nitric oxide production, which reduces the possibility to constrict venous capacity vessels. PMID:26936782

  14. Optimal design for nonlinear estimation of the hemodynamic response function.

    Science.gov (United States)

    Maus, Bärbel; van Breukelen, Gerard J P; Goebel, Rainer; Berger, Martijn P F

    2012-06-01

    Subject-specific hemodynamic response functions (HRFs) have been recommended to capture variation in the form of the hemodynamic response between subjects (Aguirre et al., [ 1998]: Neuroimage 8:360-369). The purpose of this article is to find optimal designs for estimation of subject-specific parameters for the double gamma HRF. As the double gamma function is a nonlinear function of its parameters, optimal design theory for nonlinear models is employed in this article. The double gamma function is linearized by a Taylor approximation and the maximin criterion is used to handle dependency of the D-optimal design on the expansion point of the Taylor approximation. A realistic range of double gamma HRF parameters is used for the expansion point of the Taylor approximation. Furthermore, a genetic algorithm (GA) (Kao et al., [ 2009]: Neuroimage 44:849-856) is applied to find locally optimal designs for the different expansion points and the maximin design chosen from the locally optimal designs is compared to maximin designs obtained by m-sequences, blocked designs, designs with constant interstimulus interval (ISI) and random event-related designs. The maximin design obtained by the GA is most efficient. Random event-related designs chosen from several generated designs and m-sequences have a high efficiency, while blocked designs and designs with a constant ISI have a low efficiency compared to the maximin GA design. PMID:21567658

  15. [Structure of hemodynamic responses in the central command to move].

    Science.gov (United States)

    Medvedev, O S; Vylegzhanin, A G; Matsievskiĭ, D D; Romanov, A F

    1981-11-01

    Cardiac and vascular components of the hemodynamic response to "central command" to the skeletal muscles in immobilized decerebrated cats using an experimental model of "fictitious scratching" revealed that activation of the m. gastrocnemius increased blood pressure by 57 mm Hg, whereas cardiac output and blood flow in the common iliac artery changed insignificantly. The maximal increase of the blood flow in common iliac artery depended mainly on the stimulation of beta-adrenoreceptors by circulating catecholamines. The adaptive cardio-vascular responses during "central command" to skeletal muscles seem to depend mainly on the elevation of peripheral vascular resistance, there being no specific vasodilator influences on blood vessels of the muscles receiving the "central command". PMID:7327279

  16. Hemodynamic responses to functional activation accessed by optical imaging

    Science.gov (United States)

    Ni, Songlin; Li, Pengcheng; Yang, Yuanyuan; Lv, Xiaohua; Luo, Qingming

    2006-01-01

    A multi-wavelength light-emitting diode (LED) and laser diode (LD) based optical imaging system was developed to visualize the changes in cerebral blood flow, oxygenation following functional activation simultaneously in rodent cortex. The 2-D blood flow image was accessed by laser speckle contrast imaging, and the spectroscopic imaging of intrinsic signal was used for the calculation of oxyhemoglobin (HbO), deoxyhemoglobin (Hb) and total hemoglobin (HbT) concentration. The combination of spectroscopic imaging and laser speckle contrast imaging provides the capability to simultaneously investigate the spatial and temporal blood flow and hemoglobin concentration changes with high resolution, which may lead to a better understanding of the coupling between neuronal activation and vascular responses. The optical imaging system been built is compact and convenient to investigators. And it is reliable to acquire raw data. In present study, the hemodynamic responses to cortical spreading depression (CSD) in parietal cortex of ~-chloralose/urethan anesthetized rats were demonstrated.

  17. Hemodynamic measurements in rat brain and human muscle using diffuse near-infrared absorption and correlation spectroscopies

    Science.gov (United States)

    Yu, Guoqiang; Durduran, Turgut; Furuya, D.; Lech, G.; Zhou, Chao; Chance, Britten; Greenberg, J. H.; Yodh, Arjun G.

    2003-07-01

    Measurement of concentration, oxygenation, and flow characteristics of blood cells can reveal information about tissue metabolism and functional heterogeneity. An improved multifunctional hybrid system has been built on the basis of our previous hybrid instrument that combines two near-infrared diffuse optical techniques to simultaneously monitor the changes of blood flow, total hemoglobin concentration (THC) and blood oxygen saturation (StO2). Diffuse correlation spectroscopy (DCS) monitors blood flow (BF) by measuring the optical phase shifts caused by moving blood cells, while diffuse photon density wave spectroscopy (DPDW) measures tissue absorption and scattering. Higher spatial resolution, higher data acquisition rate and higher dynamic range of the improved system allow us to monitor rapid hemodynamic changes in rat brain and human muscles. We have designed two probes with different source-detector pairs and different separations for the two types of experiments. A unique non-contact probe mounted on the back of a camera, which allows continuous measurements without altering the blood flow, was employed to in vivo monitor the metabolic responses in rat brain during KCl induced cortical spreading depression (CSD). A contact probe was used to measure changes of blood flow and oxygenation in human muscle during and after cuff occlusion or exercise, where the non-contact probe is not appropriate for monitoring the moving target. The experimental results indicate that our multifunctional hybrid system is capable of in vivo and non-invasive monitoring of the hemodynamic changes in different tissues (smaller tissues in rat brain, larger tissues in human muscle) under different conditions (static versus moving). The time series images of flow during CSD obtained by our technique revealed spatial and temporal hemodynamic changes in rat brain. Two to three fold longer recovery times of flow and oxygenation after cuff occlusion or exercise from calf flexors in a

  18. Natriuretic peptides and cerebral hemodynamics

    DEFF Research Database (Denmark)

    Guo, Song; Barringer, Filippa; Zois, Nora Elisabeth;

    2014-01-01

    decompensated disease. In contrast, their biological effects on the cerebral hemodynamics are poorly understood. In this mini-review, we summarize the hemodynamic effects of the natriuretic peptides with a focus on the cerebral hemodynamics. In addition, we will discuss its potential implications in diseases...... where alteration of the cerebral hemodynamics plays a role such as migraine and acute brain injury including stroke. We conclude that a possible role of the peptides is feasible as evaluated from animal and in vitro studies, but more research is needed in humans to determine the precise response on...... cerebral vessels....

  19. Use of lignocaine or nitroglycerine for blunting of hemodynamic stress response during electroconvulsive therapy

    Directory of Open Access Journals (Sweden)

    Muhammad Umar Zahoor

    2014-01-01

    Conclusion: NTG provided more hemodynamic stability in post-ECT period as compared to lignocaine which only prevented a surge in HR without any effect on MAP. We conclude that NTG can safely be instituted for anaesthesia in ECT patients for prevention of hemodynamic stress response.

  20. Increased sensitivity of fast BOLD fMRI with a subject-specific hemodynamic response function and application to epilepsy.

    Science.gov (United States)

    Proulx, Sébastien; Safi-Harb, Mouna; Levan, Pierre; An, Dongmei; Watanabe, Satsuki; Gotman, Jean

    2014-06-01

    Activation detection in functional Magnetic Resonance Imaging (fMRI) typically assumes the hemodynamic response to neuronal activity to be invariant across brain regions and subjects. Reports of substantial variability of the morphology of blood-oxygenation-level-dependent (BOLD) responses are accumulating, suggesting that the use of a single generic model of the expected response in general linear model (GLM) analyses does not provide optimal sensitivity due to model misspecification. Relaxing assumptions of the model can limit the impact of hemodynamic response function (HRF) variability, but at a cost on model parsimony. Alternatively, better specification of the model could be obtained from a priori knowledge of the HRF of a given subject, but the effectiveness of this approach has only been tested on simulation data. Using fast BOLD fMRI, we characterized the variability of hemodynamic responses to a simple event-related auditory-motor task, as well as its effect on activation detection with GLM analyses. We show the variability to be higher between subjects than between regions and variation in different regions to correlate from one subject to the other. Accounting for subject-related variability by deriving subject-specific models from responses to the task in some regions lead to more sensitive detection of responses in other regions. We applied the approach to epilepsy patients, where task-derived patient-specific models provided additional information compared to the use of a generic model for the detection of BOLD responses to epileptiform activity identified on scalp electro-encephalogram (EEG). This work highlights the importance of improving the accuracy of the model for detecting neuronal activation with fMRI, and the fact that it can be done at no cost to model parsimony through the acquisition of independent a priori information about the hemodynamic response. PMID:24582920

  1. Comparison of hemodynamic responses to static and dynamic exercise.

    Science.gov (United States)

    Bezucha, G R; Lenser, M C; Hanson, P G; Nagle, F J

    1982-12-01

    Eight healthy male adults (25-34 yr) were studied to compare hemodynamic responses to static exercise (30% MVC in leg extension), static-dynamic exercise (one-arm cranking, 66 and 79% VO2 max-arm), and dynamic exercise (two-leg cycling, 58 and 82% VOmax-legs). Leg extension (LE) strength was measured by a spring scale. Cranking and cycling were performed on a Quinton bicycle ergometer. VO2 was measured using an automated open-circuit system. Heart rate (HR) was monitored from a CM-5 ECG lead, and arterial pressure (Pa) was measured from an indwelling brachial artery catheter. Cardiac output (Q) was measured using a CO2-rebreathing procedure. Total peripheral resistance (TPR) was calculated using the mean arterial pressure (Pa) as the systemic pressure gradient. In 30% LE, a significant (P less than 0.05) Pa increase occurred (pressor response) mediated primarily by an increase in Q. One-arm cranking and two-leg cycling at similar relative VO2 demands resulted in nearly identical increases in Pa due to different contributions of Q and TPR. Q and the arteriovenous O2 difference varied as a function of VO2 regardless of the mode of exercise (static or dynamic). On the other hand, the HR response, which accounted for increased Q in the exercises containing a static component, and Pa varied with mode of exercise. Any generalized scheme of cardiovascular control during exercise must account for the potential influence of dynamic and static components of the exercise. PMID:7153155

  2. Effect of fiberoptic bronchoscope compared with direct laryngoscope on hemodynamic responses to orotracheal intubation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Guo-hua; XUE Fu-shan; LI Ping; SUN Hai-yan; LIU Kun-peng; XU Ya-chao; LIU Yi; SUN Hai-tao

    2007-01-01

    @@ Fiberoptic bronchoscope (FOB) is an important instrument for respiratory, disorder examination and difficult airway management.1 The fiberoptic intubation can avoid the mechanical stimulus to oropharyngolaryngeal structures thereby it is likely to attenuate hemodynamic responses during orotracheal intubation.

  3. Attenuation of hemodynamic responses to laryngoscopy and endotracheal intubation by intravenous esmolol

    Directory of Open Access Journals (Sweden)

    Gurudatta KN

    2014-06-01

    Conclusion: We conclude that esmolol in a dose of 100 mg given 2 minute before induction is highly effective in attenuation hemodynamic response to laryngoscopy and intubation. [Int J Res Med Sci 2014; 2(3.000: 866-871

  4. Low-dose esmolol: hemodynamic response to endotracheal intubation in normotensive patients

    OpenAIRE

    Lakshmanappa, Suresh; Suryanarayana, Venkatesh G; Alore, Ashley; Sathees B. Chandra

    2012-01-01

    Abstract Purpose: Endotracheal intubation is a frequently utilized and highly invasive component of anesthesia that is often accompanied by potentially harmful hemodynamic pressor responses. The purpose of this study was to investigate the efficiency of a single pre-induction 1 mg/kg bolus injection of esmolol for attenuating these hemodynamic responses to endotracheal intubation in normotensive patients. Material and methods: The study was composed of 100 randomly selected male and fe...

  5. Temporal coupling between stimulus-evoked neural activity and hemodynamic responses from individual cortical columns

    International Nuclear Information System (INIS)

    Using previously published data from the whisker barrel cortex of anesthetized rodents (Berwick et al 2008 J. Neurophysiol. 99 787-98) we investigated whether highly spatially localized stimulus-evoked cortical hemodynamics responses displayed a linear time-invariant (LTI) relationship with neural activity. Presentation of stimuli to individual whiskers of 2 s and 16 s durations produced hemodynamics and neural activity spatially localized to individual cortical columns. Two-dimensional optical imaging spectroscopy (2D-OIS) measured hemoglobin responses, while multi-laminar electrophysiology recorded neural activity. Hemoglobin responses to 2 s stimuli were deconvolved with underlying evoked neural activity to estimate impulse response functions which were then convolved with neural activity evoked by 16 s stimuli to generate predictions of hemodynamic responses. An LTI system more adequately described the temporal neuro-hemodynamics coupling relationship for these spatially localized sensory stimuli than in previous studies that activated the entire whisker cortex. An inability to predict the magnitude of an initial 'peak' in the total and oxy- hemoglobin responses was alleviated when excluding responses influenced by overlying arterial components. However, this did not improve estimation of the hemodynamic responses return to baseline post-stimulus cessation.

  6. Changes in cerebral hemodynamics in patients with posttraumatic diffuse brain swelling after external intraventricular drainage

    Institute of Scientific and Technical Information of China (English)

    Kefei Chen; Jirong Dong; Tian Xia; Chunlei Zhang; Wei Zhao; Qinyi Xu; Xuejian Cai

    2015-01-01

    Purpose: To investigate the changes of cerebral hemodynamics pre-and post-ventricular drainage in patients with posttraumatic acute diffuse brain swelling.Methods: Twenty-four cases of traumatic diffuse brain swelling were analyzed retrospectively.Patients in nonsurgical group were treated by medicine therapy.Patients in surgical group were treated by external ventricular drainage plus medicine therapy.The first CT perfusion scan was completed within 4 -5 h after trauma and scanned again after 7 days.The changes of perfusion parameters in area-of-interest in two groups were analyzed and compared before and after treatment.Result: Compared with the nonsurgical group, the value of cerebral blood volume, cerebral blood flow and mean transit time in bilateral frontal temporopadetal grey matter, basal ganglia, cerebellum, and brain stem at pre-and post-therapy were increased significantly (p < 0.05) in surgical group, and consequently the prognosis of patients undergoing surgery was also better than that of nonsurgical group.Conclusion: External ventricular drainage can improve cerebral perfusion and increase survival quality for the patients with posttraumatic acute diffuse brain swelling.

  7. Rapid stimulus-evoked astrocyte Ca2+ elevations and hemodynamic responses in mouse somatosensory cortex in vivo

    DEFF Research Database (Denmark)

    Lind, Barbara Lykke; Brazhe, Alexey; Jessen, Sanne Barsballe;

    2013-01-01

    Increased neuron and astrocyte activity triggers increased brain blood flow, but controversy exists over whether stimulation-induced changes in astrocyte activity are rapid and widespread enough to contribute to brain blood flow control. Here, we provide evidence for stimulus-evoked Ca(2......+) elevations with rapid onset and short duration in a large proportion of cortical astrocytes in the adult mouse somatosensory cortex. Our improved detection of the fast Ca(2+) signals is due to a signal-enhancing analysis of the Ca(2+) activity. The rapid stimulation-evoked Ca(2+) increases identified in...... astrocyte somas, processes, and end-feet preceded local vasodilatation. Fast Ca(2+) responses in both neurons and astrocytes correlated with synaptic activity, but only the astrocytic responses correlated with the hemodynamic shifts. These data establish that a large proportion of cortical astrocytes have...

  8. Detecting the Subtle Shape Differences in Hemodynamic Responses at the Group Level

    Directory of Open Access Journals (Sweden)

    Gang eChen

    2015-10-01

    Full Text Available The nature of the hemodynamic response (HDR is still not fully understood due to the multifaceted processes involved. Aside from the overall amplitude, the response may vary across cognitive states, tasks, brain regions, and subjects with respect to characteristics such as rise and fall speed, peak duration, undershoot shape, and overall duration. Here we demonstrate that the fixed-shape or adjusted-shape methods may fail to detect some shape subtleties. In contrast, the estimated-shape method (ESM through multiple basis functions can provide the opportunity to identify some subtle shape differences and achieve higher statistical power at both individual and group levels. Previously, some dimension reduction approaches focused on the peak magnitude, or made inferences based on the area under the curve or interaction, which can lead to potential misidentifications. By adopting a generic framework of multivariate modeling (MVM, we showcase a hybrid approach that is validated by simulations and real data. Unlike the few analyses that were limited to main effect, two- or three-way interactions, we extend the approach to an inclusive platform that is more adaptable than the conventional GLM, achieving a practical equipoise among representation, false positive control, statistical power, and modeling flexibility.

  9. Comparison of hemodynamic responses to dexmedetomidine versus esmolol in patients undergoing beating heart surgery

    OpenAIRE

    Mohamed Abdel Rahman Salem M.D,* Mostafa Elhamamsy M.D

    2001-01-01

    adrenergic agonists decrease sympathetic tone with ensuing attenuation of neuroendocrine and hemodynamic responses to anesthesia and surgery. Also, administration of beta -adrenergic antagonists contributes to prophylaxis against hypertension, tachycardia and myocardial ischemia and myocardial protection during cardiac surgery. The effects of dexmedetomidine (DEX), a highly specific alpha -adrenergic agonist, on these responses have not yet been fully reported in patients undergoing cardiac s...

  10. A signal subspace approach for modeling the hemodynamic response function in fMRI.

    Science.gov (United States)

    Hossein-Zadeh, Gholam-Ali; Ardekani, Babak A; Soltanian-Zadeh, Hamid

    2003-10-01

    Many fMRI analysis methods use a model for the hemodynamic response function (HRF). Common models of the HRF, such as the Gaussian or Gamma functions, have parameters that are usually selected a priori by the data analyst. A new method is presented that characterizes the HRF over a wide range of parameters via three basis signals derived using principal component analysis (PCA). Covering the HRF variability, these three basis signals together with the stimulation pattern define signal subspaces which are applicable to both linear and nonlinear modeling and identification of the HRF and for various activation detection strategies. Analysis of simulated fMRI data using the proposed signal subspace showed increased detection sensitivity compared to the case of using a previously proposed trigonometric subspace. The methodology was also applied to activation detection in both event-related and block design experimental fMRI data using both linear and nonlinear modeling of the HRF. The activated regions were consistent with previous studies, indicating the ability of the proposed approach in detecting brain activation without a priori assumptions about the shape parameters of the HRF. The utility of the proposed basis functions in identifying the HRF is demonstrated by estimating the HRF in different activated regions. PMID:14599533

  11. Pros and Cons of Using the Informed Basis Set to Account for Hemodynamic Response Variability with Developmental Data

    Science.gov (United States)

    Cignetti, Fabien; Salvia, Emilie; Anton, Jean-Luc; Grosbras, Marie-Hélène; Assaiante, Christine

    2016-01-01

    Conventional analysis of functional magnetic resonance imaging (fMRI) data using the general linear model (GLM) employs a neural model convolved with a canonical hemodynamic response function (HRF) peaking 5 s after stimulation. Incorporation of a further basis function, namely the canonical HRF temporal derivative, accounts for delays in the hemodynamic response to neural activity. A population that may benefit from this flexible approach is children whose hemodynamic response is not yet mature. Here, we examined the effects of using the set based on the canonical HRF plus its temporal derivative on both first- and second-level GLM analyses, through simulations and using developmental data (an fMRI dataset on proprioceptive mapping in children and adults). Simulations of delayed fMRI first-level data emphasized the benefit of carrying forward to the second-level a derivative boost that combines derivative and nonderivative beta estimates. In the experimental data, second-level analysis using a paired t-test showed increased mean amplitude estimate (i.e., increased group contrast mean) in several brain regions related to proprioceptive processing when using the derivative boost compared to using only the nonderivative term. This was true especially in children. However, carrying forward to the second-level the individual derivative boosts had adverse consequences on random-effects analysis that implemented one-sample t-test, yielding increased between-subject variance, thus affecting group-level statistic. Boosted data also presented a lower level of smoothness that had implication for the detection of group average activation. Imposing soft constraints on the derivative boost by limiting the time-to-peak range of the modeled response within a specified range (i.e., 4–6 s) mitigated these issues. These findings support the notion that there are pros and cons to using the informed basis set with developmental data. PMID:27471441

  12. A 12-week resistance training program elicits positive changes in hemodynamic responses in the elderly

    OpenAIRE

    Cinthya Campos Salazar; Norbel Román Garita

    2009-01-01

    The aim of the study was to determine the effect of a resistance training program in hemodynamic responses and adaptations in 60 yr. old elderly. Volunteers were 60 healthy-elderly who underwent a training program 3 times/wk. for 12 wk. Participants were randomly assigned to either a control group, an exercise group who trained at 30% intensity of 5 maximal repetitions (5RM) (30% of 5RM) or an exercise group at an intensity of 70% (70% of 5RM). Hemodynamic variables measured were mean arteria...

  13. Variability in prefrontal hemodynamic response during exposure to repeated self-selected music excerpts, a near-infrared spectroscopy study.

    Directory of Open Access Journals (Sweden)

    Saba Moghimi

    Full Text Available Music-induced brain activity modulations in areas involved in emotion regulation may be useful in achieving therapeutic outcomes. Clinical applications of music may involve prolonged or repeated exposures to music. However, the variability of the observed brain activity patterns in repeated exposures to music is not well understood. We hypothesized that multiple exposures to the same music would elicit more consistent activity patterns than exposure to different music. In this study, the temporal and spatial variability of cerebral prefrontal hemodynamic response was investigated across multiple exposures to self-selected musical excerpts in 10 healthy adults. The hemodynamic changes were measured using prefrontal cortex near infrared spectroscopy and represented by instantaneous phase values. Based on spatial and temporal characteristics of these observed hemodynamic changes, we defined a consistency index to represent variability across these domains. The consistency index across repeated exposures to the same piece of music was compared to the consistency index corresponding to prefrontal activity from randomly matched non-identical musical excerpts. Consistency indexes were significantly different for identical versus non-identical musical excerpts when comparing a subset of repetitions. When all four exposures were compared, no significant difference was observed between the consistency indexes of randomly matched non-identical musical excerpts and the consistency index corresponding to repetitions of the same musical excerpts. This observation suggests the existence of only partial consistency between repeated exposures to the same musical excerpt, which may stem from the role of the prefrontal cortex in regulating other cognitive and emotional processes.

  14. Comparison of hemodynamic responses to dexmedetomidine versus esmolol in patients undergoing beating heart surgery

    Directory of Open Access Journals (Sweden)

    Mohamed Abdel Rahman Salem M.D,* Mostafa Elhamamsy M.D

    2001-09-01

    Full Text Available adrenergic agonists decrease sympathetic tone with ensuing attenuation of neuroendocrine and hemodynamic responses to anesthesia and surgery. Also, administration of beta -adrenergic antagonists contributes to prophylaxis against hypertension, tachycardia and myocardial ischemia and myocardial protection during cardiac surgery. The effects of dexmedetomidine (DEX, a highly specific alpha -adrenergic agonist, on these responses have not yet been fully reported in patients undergoing cardiac surgery. Esmolol (ESM is a cardioselective, short-acting -blocking agent. Previous studies have established the effectiveness of esmolol in the reduction of hemodynamic responses during anesthetic induction. Aim: The study of hemodynamic responses of dexmedetomidine and esmolol and their effects on the anesthetic requirements during anesthesia in beating heart surgery. Methods: Forty patients scheduled for elective beating heart surgery received a !thereaf"#$%!&'" end of surgery in the ESM group. Total intravenous anesthesia using fentanyl, cisatracurium a"( -* +of surgery. Hemodynamics measured included heart rate, mean arterial pressure, filling pressures, cardiac index, systemic and pulmonary vascular resistances. The incidence of hypotension, hypertension, tachycardia, bradycardia, dysrhythmias, ST segment changes, total anesthetics requirements, muscle rigidity and postoperative shivering were recorded. Results: #$%",-.&/ 0*! 0 ! l/min/m ( 1 ! + 2

  15. The Changes in the Hemodynamic Activity of the Brain during Motor Imagery Training with the Use of Brain-Computer Interface1

    Czech Academy of Sciences Publication Activity Database

    Frolov, A. A.; Húsek, Dušan; Silchenko, A.V.; Tintěra, J.; Rydlo, J.

    2016-01-01

    Roč. 42, č. 1 (2016), s. 1-12. ISSN 0362-1197 R&D Projects: GA MŠk ED1.1.00/02.0070 Grant ostatní: GA MŠk(CZ) EE.2.3.20.0073 Institutional support: RVO:67985807 Keywords : brain-computer interface * motor imagery * hemodynamic activity * brain plasticity * functional MRI Subject RIV: IN - Informatics, Computer Science

  16. Fusion of fNIRS and fMRI data: Identifying when and where hemodynamic signals are changing in human brains

    Directory of Open Access Journals (Sweden)

    Zhen Yuan

    2013-10-01

    Full Text Available In this study we implemented a new imaging method to fuse functional near infrared spectroscopy (fNIRS measurements and functional magnetic resonance imaging (fMRI data to reveal the spatiotemporal dynamics of the hemodynamic responses with high spatiotemporal resolution across the brain. We evaluated this method using multimodal data acquired from human right finger tapping tasks. And we found the proposed method is able to clearly identify from the linked components of fMRI and fNIRS where and when the hemodynamic signals are changing. In particular, the estimated associations between fNIRS and fMRI will be displayed as time varying spatial fMRI maps along with the fNIRS time courses. In addition, the joint components between fMRI and fNIRS are combined together to generate full spatiotemporal “snapshots” and movies, which provides an excellent way to examine the dynamic interplay between hemodynamic fNIRS and fMRI measurements.

  17. Hemodynamic Segmentation of Brain Perfusion Images with Delay and Dispersion Effects Using an Expectation-Maximization Algorithm

    OpenAIRE

    Lu, Chia-Feng; Guo, Wan-Yuo; Chang, Feng-Chi; Huang, Shang-Ran; Chou, Yen-Chun; Wu, Yu-Te

    2013-01-01

    Automatic identification of various perfusion compartments from dynamic susceptibility contrast magnetic resonance brain images can assist in clinical diagnosis and treatment of cerebrovascular diseases. The principle of segmentation methods was based on the clustering of bolus transit-time profiles to discern areas of different tissues. However, the cerebrovascular diseases may result in a delayed and dispersed local perfusion and therefore alter the hemodynamic signal profiles. Assessing th...

  18. Attenuation of hemodynamic responses to laryngoscopy and endotracheal intubation by intravenous esmolol

    OpenAIRE

    Gurudatta KN; Kiran Mallappa; Ravindra GL

    2014-01-01

    Background: Sympathetic response associated with laryngoscopy and endotracheal intubation is a potential cause for a number of complications especially in patients with cardio-vascular compromise. The aim of our study was to evaluate and study the efficiency of intravenous esmolol in the attenuation of hemodynamic response to laryngoscopy and intubation in normotensive individuals. Methods: 100 surgical patients of either sex of physical status ASA I/II were randomly divided into 2 groups....

  19. Spatial relationship between flavoprotein fluorescence and the hemodynamic response in the primary visual cortex of alert macaque monkeys

    Directory of Open Access Journals (Sweden)

    Yevgeniy B Sirotin

    2010-06-01

    Full Text Available Flavoprotein fluorescence imaging (FFI is a novel intrinsic optical signal that is steadily gaining ground as a valuable imaging tool in neuroscience research due to its closer relationship with local metabolism relative to the more commonly used hemodynamic signals. We have developed a technique for FFI imaging in the primary visual cortex (V1 of alert monkeys. Due to the nature of neurovascular coupling, hemodynamic signals are known to spread beyond the locus of metabolic activity. To determine whether FFI signals could provide a more focal measure of cortical activity in alert animals, we compared FFI and hemodynamic point spreads (i.e. responses to a minimal visual stimulus and functional mapping signals over V1 in macaques performing simple fixation tasks. FFI responses were biphasic, with an early and focal fluorescence increase followed by a delayed and spatially broader fluorescence decrease. As expected, the early fluorescence increase, indicating increased local oxidative metabolism, was somewhat narrower than the simultaneously observed hemodynamic response. However, the later FFI decrease was broader than the hemodynamic response and started prior to the cessation of visual stimulation suggesting different mechanisms underlying the two phases of the fluorescence signal. FFI mapping signals were free of vascular artifacts and comparable in amplitude to hemodynamic mapping signals. These results indicate that the FFI response may be a more local and direct indicator of cortical metabolism than the hemodynamic response in alert animals.

  20. The comparison of the effects of dexmedetomidine, fentanyl and esmolol on prevention of hemodynamic response to intubation

    OpenAIRE

    Nermin Gogus; Belgin Akan; Nurten Serger; Mustafa Baydar

    2014-01-01

    Background and objectives: Laryngoscopy and intubation can cause hemodynamic response. Various medications may be employed to control that response. In this study, we aimed to compare the effects of dexmedetomidine, fentanyl and esmolol on hemodynamic response. Methods: Ninety elective surgery patients who needed endotracheal intubation who were in American Society of Anesthesiology I–II group and ages between 21 and 65 years were included in that prospective, randomized, double-blind study...

  1. Hemodynamic and neuroendocrine responses to changes in sodium intake in compensated heart failure

    DEFF Research Database (Denmark)

    Damgaard, Morten; Norsk, Peter; Gustafsson, Finn; Kanters, Jørgen Kim; Christensen, Niels Juel; Bie, Peter; Friberg, Lars; Gadsbøll, Niels

    2006-01-01

    Patients with untreated heart failure (HF) exhibit a blunted hemodynamic and neuroendocrine response to a high sodium intake, leading to excessive sodium and water retention. However, it is not known whether this is the case for patients with compensated HF receiving angiotensin-converting enzyme...... inhibitors and beta-adrenoreceptor blockers. Therefore, we determined the hemodynamic and neuroendocrine responses to 1 wk of a low-sodium diet (70 mmol/day) and 1 wk of a high-sodium diet (250 mmol/day) in 12 HF patients and 12 age-matched controls in a randomized, balanced fashion. During steady...... unchanged. In conclusion, high sodium intake was tolerated without any excessive sodium and water retention in medically treated patients with compensated HF. The observation that high sodium intake improves cardiac performance, induces peripheral vasodilatation, and suppresses the release of...

  2. Prolonged hemodynamic response during incidental facial emotion processing in inter-episode bipolar I disorder

    OpenAIRE

    Rosenfeld, Ethan S.; Godfrey D. Pearlson; Sweeney, John A.; Tamminga, Carol A.; Keshavan, Matcheri S; Nonterah, Camilla; Stevens, Michael C.

    2014-01-01

    This fMRI study examined whether hemodynamic responses to affectively-salient stimuli were abnormally prolonged in remitted bipolar disorder, possibly representing a novel illness biomarker. A group of 18 DSM-IV bipolar I-diagnosed adults in remission and a demographically-matched control group performed an event-related fMRI gender-discrimination task in which face stimuli had task-irrelevant neutral, happy or angry expressions designed to elicit incidental emotional processing. Participants...

  3. Exercise-based cardiac rehabilitation improves hemodynamic responses after coronary artery bypass graft surgery

    OpenAIRE

    Ghashghaei, Fatemeh Esteki; Sadeghi, Masoumeh; Marandi, Seyed Mohammad; Ghashghaei, Samira Esteki

    2012-01-01

    BACKGROUND: Cardiovascular disorders are an important public health problem worldwide. They are also the leading cause of mortality and morbidity. Therefore, American Heart Association proposed cardiac rehabilitation program as an essential part of care for cardiac patients to improve functional capacity. The aim of this study was to evaluate the effectiveness of cardiac rehabilitation program on functional status and some hemodynamic responses in patients after coronary artery bypass graft (...

  4. Effect of uninostril yoga breathing on brain hemodynamics: A functional near-infrared spectroscopy study

    Science.gov (United States)

    Singh, Karamjit; Bhargav, Hemant; Srinivasan, TM

    2016-01-01

    Objectives: To measure the effect of the right and left nostril yoga breathing on frontal hemodynamic responses in 32 right handed healthy male subjects within the age range of 18–35 years (23.75 ± 4.14 years). Materials and Methods: Each subject practiced right nostril yoga breathing (RNYB), left nostril yoga breathing (LNYB) or breath awareness (BA) (as control) for 10 min at the same time of the day for three consecutive days, respectively. The sequence of intervention was assigned randomly. The frontal hemodynamic response in terms of changes in the oxygenated hemoglobin (oxyHb), deoxygenated hemoglobin (deoxyHb), and total hemoglobin (totalHb or blood volume) concentration was tapped for 5 min before (pre) and 10 min during the breathing practices using a 16 channel functional near-infrared system (FNIR100-ACK-W, BIOPAC Systems, Inc., U.S.A.). Average of the eight channels on each side (right and left frontals) was obtained for the two sessions (pre and during). Data was analyzed using SPSS version 10.0 through paired and independent samples t-test. Results: Within group comparison showed that during RNYB, oxyHb levels increased significantly in the left prefrontal cortex (PFC) as compared to the baseline (P = 0.026). LNYB showed a trend towards significance for reduction in oxyHb in the right hemisphere (P = 0.057). Whereas BA caused significant reduction in deoxyHb (P = 0.023) in the left hemisphere. Between groups comparison revealed that oxyHb and blood volume in the left PFC increased significantly during RNYB as compared to BA (oxyHb: P =0.012; TotalHb: P =0.017) and LNYB (oxyHb: P =0.024; totalHb: P =0.034). Conclusion: RNYB increased oxygenation and blood volume in the left PFC as compared to BA and LNYB. This supports the relationship between nasal cycle and ultradian rhythm of cerebral dominance and suggests a possible application of uninostril yoga breathing in the management of psychopathological states which show lateralized cerebral

  5. Comparing GlideScope Video Laryngoscope and Macintosh Laryngoscope Regarding Hemodynamic Responses During Orotracheal Intubation: A Randomized Controlled Trial

    OpenAIRE

    Pournajafian, Ali Reza; Ghodraty, Mohammad Reza; Faiz, Seyed Hamid Reza; Rahimzadeh, Poupak; Goodarzynejad, Hamidreza; Dogmehchi, Enseyeh

    2014-01-01

    Background: To determine if the GlideScope® videolaryngoscope (GVL) could attenuate the hemodynamic responses to orotracheal intubation compared with conventional Macintosh laryngoscope. Objectives: The aim of this relatively large randomized trial was to compare the hemodynamic stress responses during laryngoscopy and tracheal intubation using GVL versus MCL amongst healthy adult individuals receiving general anesthesia for elective surgeries. Patients and Methods: Ninety five healthy adult ...

  6. Prospective randomized study to compare between intravenous dexmedetomidine and esmolol for attenuation of hemodynamic response to endotracheal intubation

    OpenAIRE

    Selvaraj, Venkatesh; Manoharan, Karthik Raj

    2016-01-01

    Background: Esmolol has an established role in attenuation of hemodynamic response to laryngoscopy and endotracheal intubation. We studied the effect of dexmedetomidine compared to that of esmolol in this study. Aim: To study the role of dexmedetomidine in attenuation of hemodynamic response to laryngoscopy and oral endotracheal intubation compared to that of esmolol hydrochloride in patients posted for elective surgery under general anesthesia. Study Design: Prospective randomized study doub...

  7. Hemodynamic and neuroendocrine responses to changes in sodium intake in compensated heart failure

    DEFF Research Database (Denmark)

    Damgaard, Morten; Norsk, Peter; Gustafsson, Finn;

    2005-01-01

    Patients with untreated heart failure (HF) exhibit a blunted hemodynamic and neuroendocrine response to a high sodium intake, leading to excessive sodium and water retention. However, it is not known whether this is the case for patients with compensated HF receiving angiotensin-converting enzyme...... unchanged. In conclusion, high sodium intake was tolerated without any excessive sodium and water retention in medically treated patients with compensated HF. The observation that high sodium intake improves cardiac performance, induces peripheral vasodilatation, and suppresses the release of......-state conditions, hemodynamic and neuroendocrine examinations were performed at rest and during bicycle exercise. In seated HF patients, high sodium intake increased body weight (1.6 +/- 0.4%), plasma volume (9 +/- 2%), cardiac index (14 +/- 6%), and stroke volume index (21 +/- 5%), whereas mean arterial pressure...

  8. Empirical Evaluation of Visual Fatigue from Display Alignment Errors Using Cerebral Hemodynamic Responses

    Directory of Open Access Journals (Sweden)

    Hanniebey D. Wiyor

    2013-01-01

    Full Text Available The purpose of this study was to investigate the effect of stereoscopic display alignment errors on visual fatigue and prefrontal cortical tissue hemodynamic responses. We collected hemodynamic data and perceptual ratings of visual fatigue while participants performed visual display tasks on 8 ft × 6 ft NEC LT silver screen with NEC LT 245 DLP projectors. There was statistical significant difference between subjective measures of visual fatigue before air traffic control task (BATC and after air traffic control task (ATC 3, (P<0.05. Statistical significance was observed between left dorsolateral prefrontal cortex oxygenated hemoglobin (l DLPFC-HbO2, left dorsolateral prefrontal cortex deoxygenated hemoglobin (l DLPFC-Hbb, and right dorsolateral prefrontal cortex deoxygenated hemoglobin (r DLPFC-Hbb on stereoscopic alignment errors (P<0.05. Thus, cortical tissue oxygenation requirement in the left hemisphere indicates that the effect of visual fatigue is more pronounced in the left dorsolateral prefrontal cortex.

  9. Multivariate analysis of correlation between electrophysiological and hemodynamic responses during cognitive processing.

    Science.gov (United States)

    Kujala, Jan; Sudre, Gustavo; Vartiainen, Johanna; Liljeström, Mia; Mitchell, Tom; Salmelin, Riitta

    2014-05-15

    Animal and human studies have frequently shown that in primary sensory and motor regions the BOLD signal correlates positively with high-frequency and negatively with low-frequency neuronal activity. However, recent evidence suggests that this relationship may also vary across cortical areas. Detailed knowledge of the possible spectral diversity between electrophysiological and hemodynamic responses across the human cortex would be essential for neural-level interpretation of fMRI data and for informative multimodal combination of electromagnetic and hemodynamic imaging data, especially in cognitive tasks. We applied multivariate partial least squares correlation analysis to MEG-fMRI data recorded in a reading paradigm to determine the correlation patterns between the data types, at once, across the cortex. Our results revealed heterogeneous patterns of high-frequency correlation between MEG and fMRI responses, with marked dissociation between lower and higher order cortical regions. The low-frequency range showed substantial variance, with negative and positive correlations manifesting at different frequencies across cortical regions. These findings demonstrate the complexity of the neurophysiological counterparts of hemodynamic fluctuations in cognitive processing. PMID:24518260

  10. Comparison of hemodynamic response to tracheal intubation with Macintosh and McCoy laryngoscopes

    Directory of Open Access Journals (Sweden)

    Mehtab A Haidry

    2013-01-01

    Full Text Available Background: Use of McCoy blade laryngoscope avoids the lifting force in the vallecula and theoretically should lead to a lower hemodynamic response related to laryngoscopy and tracheal intubation. The available literature on the topic is conflicting. Materials and Methods: We studied the hemodynamic response to laryngoscopy and tracheal intubation in 60 ASA 1 AND 2 adult patients using either Macintosh or McCoy laryngoscopes. The change in systolic, diastolic, mean arterial pressure, and heart rate (HR was observed for 10 min post intubation. Arrhythmias and ST changes were also observed. Results: The maximum change in HR was 18.7% in the Macintosh and 7.7% in the McCoy group, and in systolic arterial pressure was 22.9% in the Macintosh and 10.3% in the McCoy group. This difference between groups was significant ( P < 0.0001. The change lasted for a lesser duration in the McCoy group. No arrhythmias or ST changes were observed in either group. Conclusion: Hemodynamic changes with use of McCoy laryngoscope were lesser in magnitude and of shorter duration.

  11. A 12-week resistance training program elicits positive changes in hemodynamic responses in the elderly

    Directory of Open Access Journals (Sweden)

    Cinthya Campos Salazar

    2009-03-01

    Full Text Available The aim of the study was to determine the effect of a resistance training program in hemodynamic responses and adaptations in 60 yr. old elderly. Volunteers were 60 healthy-elderly who underwent a training program 3 times/wk. for 12 wk. Participants were randomly assigned to either a control group, an exercise group who trained at 30% intensity of 5 maximal repetitions (5RM (30% of 5RM or an exercise group at an intensity of 70% (70% of 5RM. Hemodynamic variables measured were mean arterial pressure (MAP, calculated before and immediately after the training session, and rate pressure product (RPP, estimated once a month and before and after finishing the program. Results indicated that resistance exercise training at 30% and 70% of 5RM, with a total exercise work of 872.7 and 890.9 kg did not elicited cardiovascular risks for the elderly. A 12-wk resistance exercise training reduced the cardiovascular strain as shown by the RPP (~16% and the MAP (~9%, with no adverse effects throughout the program. Unfortunately, all the hemodynamic benefits were reverted 6 days following completion of the program. In conclusion, a healthy elderly population must perform resistance training exercises to significantly reduce the cardiovascular stress. We suggest to conduct further research that looks into different exercise intensities in longer program duration and to determine the mechanisms responsible for the deleterious effects of the detraining by using physiological, biochemical and biomechanical variables.

  12. Assessment of pedophilia using hemodynamic brain response to sexual stimuli

    DEFF Research Database (Denmark)

    Ponseti, Jorge; Granert, Oliver; Jansen, Olav;

    2012-01-01

    Accurately assessing sexual preference is important in the treatment of child sex offenders. Phallometry is the standard method to identify sexual preference; however, this measure has been criticized for its intrusiveness and limited reliability....

  13. The Pentax airway scope versus the Macintosh laryngoscope: Comparison of hemodynamic responses and concentrations of plasma norepinephrine to tracheal intubation

    OpenAIRE

    Lee, Heeseung

    2013-01-01

    Background The Pentax Airway Scope (AWS) is a video laryngoscope designed to facilitate tracheal intubation with a high-resolution image. The Pentax AWS has been reported to cause less hemodynamic stress than the Macintosh laryngoscope. The aims of this study are to investigate the differences in hemodynamic responses and norepinephrine concentrations to tracheal intubation between procedures using he Pentax AWS and the Macintosh laryngoscope. Methods Forty patients (American Society of Anest...

  14. Comparison of the efficacy of dexmedetomidine and esmolol in the treatment of increased hemodynamic response during the recovery period

    OpenAIRE

    GÜNAY, Hülya; Moğol, Elif Başağan; Kaya, Fatma Nur; Türker, Gürkan; Yavaşcaoğlu, Belgin; Ahun, Filiz; Bebek, Ayşe Neslihan; Yeniaydoğmuş, Tuba

    2012-01-01

    Objectives: Our aim was to compare effectiveness of esmolol and dexmedetomidine in the treatment of increased hemodynamic response during anesthesia recovery period. Materials and methods: 60 ASA I-II patients whom scheduled for elective surgery with endotracheal intubation were randomized before extubation according to their hemodynamic parameters that were increased 20% of their baseline values in order to receive 1mg/kg esmolol (Group Esmolol, n= 30) or 0.5 µg/kg dexmedetomid...

  15. Comparative study of hemodynamic responses to orotracheal intubation with intubating laryngeal mask airway and direct laryngoscope

    Institute of Scientific and Technical Information of China (English)

    ZHANG Guo-hua; XUE Fu-shan; SUN Hai-yan; LI Cheng-wen; SUN Hai-tao; LI Ping; LIU Kun-peng

    2006-01-01

    Background Intubating laryngeal mask airway (ILMA) offers a new approach for orotracheal intubation and is expected to produce less cardiovascular stress responses. However, the available studies provide inconsistent results. The purpose of this study was to identify whether there is a clinically relevant difference in hemodynamic responses to orotracheal intubation by using ILMA and direct laryngoscope (DLS).Methods A total of 53 adult patients, ASA physical status Ⅰ-Ⅱ, scheduled for elective plastic surgery under general anesthesia requiring the orotracheal intubation, were randomly allocated to either DLS or ILMA groups.After a standard intravenous anesthesia induction, orotracheal intubation was performed. Noninvasive blood pressure and heart rate were recorded before (baseline values) and after anesthesia induction (post-induction values), at intubation and every minute for the first 5 minutes after intubation. The data were analyzed using Chisquare test, paired and unpaired Student's t test, and repeated-measures analysis of variance as appropriate.Results The mean intubation time in the ILMA group was longer than that in the DLS group (P<0.05). The blood pressure and heart rate increased significantly after intubation in the two groups compared to the postinduction values (P<0.05), but the maximum value of blood pressure during the observation did not exceed the baseline value, while the maximum value of heart rate was higher than the baseline (P<0.05). During the observation, there were no significant differences in blood pressure and heart rate among each time point and in the maximum values between the two groups.Conclusions Orotracheal intubations by using ILMA and DLS produce similar hemodynamic response. ILMA has no advantage in attenuating the hemodynamic responses to orotracheal intubation compared with DLS.

  16. Retrieving the Hemodynamic Response Function in resting state fMRI: Methodology and application.

    Science.gov (United States)

    Wu, Guo-Rong; Deshpande, Gopikhrishna; Laureys, Steven; Marinazzo, Daniele

    2015-08-01

    In this paper we present a procedure to retrieve the hemodynamic response function (HRF) from resting state functional magnetic resonance imaging (fMRI) data. The fundamentals of the procedures are further validated by considering simultaneous electroencephalographic (EEG) recordings. The typical HRF shape at rest for a group of healthy subject is presented. Then we present the modifications to the shape of the HRF at rest following two physiological modulations: eyes open versus eyes closed and propofol-induced modulations of consciousness. PMID:26737671

  17. Hemodynamic segmentation of brain perfusion images with delay and dispersion effects using an expectation-maximization algorithm.

    Science.gov (United States)

    Lu, Chia-Feng; Guo, Wan-Yuo; Chang, Feng-Chi; Huang, Shang-Ran; Chou, Yen-Chun; Wu, Yu-Te

    2013-01-01

    Automatic identification of various perfusion compartments from dynamic susceptibility contrast magnetic resonance brain images can assist in clinical diagnosis and treatment of cerebrovascular diseases. The principle of segmentation methods was based on the clustering of bolus transit-time profiles to discern areas of different tissues. However, the cerebrovascular diseases may result in a delayed and dispersed local perfusion and therefore alter the hemodynamic signal profiles. Assessing the accuracy of the segmentation technique under delayed/dispersed circumstance is critical to accurately evaluate the severity of the vascular disease. In this study, we improved the segmentation method of expectation-maximization algorithm by using the results of hierarchical clustering on whitened perfusion data as initial parameters for a mixture of multivariate Gaussians model. In addition, Monte Carlo simulations were conducted to evaluate the performance of proposed method under different levels of delay, dispersion, and noise of signal profiles in tissue segmentation. The proposed method was used to classify brain tissue types using perfusion data from five normal participants, a patient with unilateral stenosis of the internal carotid artery, and a patient with moyamoya disease. Our results showed that the normal, delayed or dispersed hemodynamics can be well differentiated for patients, and therefore the local arterial input function for impaired tissues can be recognized to minimize the error when estimating the cerebral blood flow. Furthermore, the tissue in the risk of infarct and the tissue with or without the complementary blood supply from the communicating arteries can be identified. PMID:23894386

  18. Hemodynamic Segmentation of Brain Perfusion Images with Delay and Dispersion Effects Using an Expectation-Maximization Algorithm

    Science.gov (United States)

    Lu, Chia-Feng; Guo, Wan-Yuo; Chang, Feng-Chi; Huang, Shang-Ran; Chou, Yen-Chun; Wu, Yu-Te

    2013-01-01

    Automatic identification of various perfusion compartments from dynamic susceptibility contrast magnetic resonance brain images can assist in clinical diagnosis and treatment of cerebrovascular diseases. The principle of segmentation methods was based on the clustering of bolus transit-time profiles to discern areas of different tissues. However, the cerebrovascular diseases may result in a delayed and dispersed local perfusion and therefore alter the hemodynamic signal profiles. Assessing the accuracy of the segmentation technique under delayed/dispersed circumstance is critical to accurately evaluate the severity of the vascular disease. In this study, we improved the segmentation method of expectation-maximization algorithm by using the results of hierarchical clustering on whitened perfusion data as initial parameters for a mixture of multivariate Gaussians model. In addition, Monte Carlo simulations were conducted to evaluate the performance of proposed method under different levels of delay, dispersion, and noise of signal profiles in tissue segmentation. The proposed method was used to classify brain tissue types using perfusion data from five normal participants, a patient with unilateral stenosis of the internal carotid artery, and a patient with moyamoya disease. Our results showed that the normal, delayed or dispersed hemodynamics can be well differentiated for patients, and therefore the local arterial input function for impaired tissues can be recognized to minimize the error when estimating the cerebral blood flow. Furthermore, the tissue in the risk of infarct and the tissue with or without the complementary blood supply from the communicating arteries can be identified. PMID:23894386

  19. Hemodynamic segmentation of brain perfusion images with delay and dispersion effects using an expectation-maximization algorithm.

    Directory of Open Access Journals (Sweden)

    Chia-Feng Lu

    Full Text Available Automatic identification of various perfusion compartments from dynamic susceptibility contrast magnetic resonance brain images can assist in clinical diagnosis and treatment of cerebrovascular diseases. The principle of segmentation methods was based on the clustering of bolus transit-time profiles to discern areas of different tissues. However, the cerebrovascular diseases may result in a delayed and dispersed local perfusion and therefore alter the hemodynamic signal profiles. Assessing the accuracy of the segmentation technique under delayed/dispersed circumstance is critical to accurately evaluate the severity of the vascular disease. In this study, we improved the segmentation method of expectation-maximization algorithm by using the results of hierarchical clustering on whitened perfusion data as initial parameters for a mixture of multivariate Gaussians model. In addition, Monte Carlo simulations were conducted to evaluate the performance of proposed method under different levels of delay, dispersion, and noise of signal profiles in tissue segmentation. The proposed method was used to classify brain tissue types using perfusion data from five normal participants, a patient with unilateral stenosis of the internal carotid artery, and a patient with moyamoya disease. Our results showed that the normal, delayed or dispersed hemodynamics can be well differentiated for patients, and therefore the local arterial input function for impaired tissues can be recognized to minimize the error when estimating the cerebral blood flow. Furthermore, the tissue in the risk of infarct and the tissue with or without the complementary blood supply from the communicating arteries can be identified.

  20. Voluntary Modulation of Hemodynamic Responses in Swallowing Related Motor Areas: A Near-Infrared Spectroscopy-Based Neurofeedback Study

    Science.gov (United States)

    Kober, Silvia Erika; Gressenberger, Bettina; Kurzmann, Jürgen; Neuper, Christa; Wood, Guilherme

    2015-01-01

    In the present study, we show for the first time that motor imagery of swallowing, which is defined as the mental imagination of a specific motor act without overt movements by muscular activity, can be successfully used as mental strategy in a neurofeedback training paradigm. Furthermore, we demonstrate its effects on cortical correlates of swallowing function. Therefore, N = 20 healthy young adults were trained to voluntarily increase their hemodynamic response in swallowing related brain areas as assessed with near-infrared spectroscopy (NIRS). During seven training sessions, participants received either feedback of concentration changes in oxygenated hemoglobin (oxy-Hb group, N = 10) or deoxygenated hemoglobin (deoxy-Hb group, N = 10) over the inferior frontal gyrus (IFG) during motor imagery of swallowing. Before and after the training, we assessed cortical activation patterns during motor execution and imagery of swallowing. The deoxy-Hb group was able to voluntarily increase deoxy-Hb over the IFG during imagery of swallowing. Furthermore, swallowing related cortical activation patterns were more pronounced during motor execution and imagery after the training compared to the pre-test, indicating cortical reorganization due to neurofeedback training. The oxy-Hb group could neither control oxy-Hb during neurofeedback training nor showed any cortical changes. Hence, successful modulation of deoxy-Hb over swallowing related brain areas led to cortical reorganization and might be useful for future treatments of swallowing dysfunction. PMID:26575032

  1. Hemodynamic Changes during a Deep Inspiration Maneuver Predict Fluid Responsiveness in Spontaneously Breathing Patients

    Directory of Open Access Journals (Sweden)

    Sébastien Préau

    2012-01-01

    Full Text Available Objective. We hypothesized that the hemodynamic response to a deep inspiration maneuver (DIM indicates fluid responsiveness in spontaneously breathing (SB patients. Design. Prospective study. Setting. ICU of a general hospital. Patients. Consecutive nonintubated patients without mechanical ventilation, considered for volume expansion (VE. Intervention. We assessed hemodynamic status at baseline and after VE. Measurements and Main Results. We measured radial pulse pressure (PP using an arterial catheter and peak velocity of femoral artery flow (VF using continuous Doppler. Changes in PP and VF induced by a DIM (ΔPPdim and ΔVFdim were calculated in 23 patients. ΔPPdim and ΔVFdim ≥12% predicted responders to VE with sensitivity of 90% and specificity of 100%. Conclusions. In a restricted population of SB patients with severe sepsis or acute pancreatitis, ΔPPdim and ΔVFdim are accurate indices for predicting fluid responsiveness. These results should be confirmed in a larger population before validating their use in current practice.

  2. Body position does not affect the hemodynamic response to venous air embolism in dogs

    Science.gov (United States)

    Mehlhorn, U.; Burke, E. J.; Butler, B. D.; Davis, K. L.; Katz, J.; Melamed, E.; Morris, W. P.; Allen, S. J.

    1994-01-01

    Current therapy for massive venous air embolism (VAE) includes the use of the left lateral recumbent (LLR) position. This recommendation is based on animal studies, conducted 50 yr ago, which looked primarily at survival. Little is known, however, about the concomitant hemodynamic response after VAE in various body positions. The purpose of this study was to investigate the hemodynamic and cardiovascular changes in various body positions after VAE. Twenty-two mechanically ventilated supine mongrel dogs received a venous air infusion of 2.5 mL/kg at a rate of 5 mL/s. One minute after the infusion, 100% oxygen ventilation was commenced and the body position of the dogs was changed to either the LLR (n = 6), the LLR with the head 10 degrees down (LLR-10 degrees; n = 6) or the right lateral recumbent (RLR; n = 5) position. Five dogs were maintained in the supine position (SUP; n = 5). One dog died in every group except in the SUP group, where all the dogs recovered. There were no significant differences among the various body positions in terms of heart rate, mean arterial pressure, pulmonary artery pressure, central venous pressure, left ventricular end-diastolic pressure, or cardiac output. The acute hemodynamic changes occurring during the first 5-15 min after VAE recovered to 80% of control within 60 min. Our data suggest that body repositioning does not influence the cardiovascular response to VAE. Specifically, our data do not support the recommendation of repositioning into the LLR position for the treatment of VAE.

  3. Relationship between prefrontal hemodynamic responses and quality of life differs between melancholia and non-melancholic depression.

    Science.gov (United States)

    Tsujii, Noa; Mikawa, Wakako; Tsujimoto, Emi; Akashi, Hiroyuki; Adachi, Toru; Kirime, Eiji; Shirakawa, Osamu

    2016-07-30

    This study aimed to determine whether quality of life (QOL) reflects specific functional abnormalities of frontotemporal hemodynamic responses in melancholia. We recruited 30 patients with major depressive disorder (MDD) with melancholic features (MDD-MF), 52 with non-melancholic features (MDD-NMF), and 68 healthy control subjects who were matched for age, sex ratio, and years of education. QOL was assessed using the Medical Outcomes Study 36-item Short-Form Health Survey (SF-36), and regional hemodynamic responses during a verbal fluency task were monitored with near-infrared spectroscopy (NIRS). Patients with MDD-MF scored significantly lower than those with MDD-NMF on the role emotional domain of SF-36. Both MDD patient groups exhibited lower hemodynamic responses in the frontotemporal regions than the control group. Hemodynamic responses in the frontotemporal regions were significantly smaller in patients with MDD-MF than in those with MDD-NMF. The role emotional domain of patients with MDD-MF was significantly and positively correlated with hemodynamic responses in the prefrontal region, whereas that of patients with MDD-NMF revealed no significant correlation. In conclusion, our results indicate that patients with MDD-MF exhibit qualitatively distinct prefrontal dysfunction patterns associated with emotional role functioning compared with patients with MDD-NMF. PMID:27259838

  4. Interneurons contribute to the hemodynamic/metabolic response to epileptiform discharges.

    Science.gov (United States)

    Saillet, Sandrine; Quilichini, Pascale P; Ghestem, Antoine; Giusiano, Bernard; Ivanov, Anton I; Hitziger, Sebastian; Vanzetta, Ivo; Bernard, Christophe; Bénar, Christian-G

    2016-03-01

    Interpretation of hemodynamic responses in epilepsy is hampered by an incomplete understanding of the underlying neurovascular coupling, especially the contributions of excitation and inhibition. We made simultaneous multimodal recordings of local field potentials (LFPs), firing of individual neurons, blood flow, and oxygen level in the somatosensory cortex of anesthetized rats. Epileptiform discharges induced by bicuculline injections were used to trigger large local events. LFP and blood flow were robustly coupled, as were LFP and tissue oxygen. In a parametric linear model, LFP and the baseline activities of cerebral blood flow and tissue partial oxygen tension contributed significantly to blood flow and oxygen responses. In an analysis of recordings from 402 neurons, blood flow/tissue oxygen correlated with the discharge of putative interneurons but not of principal cells. Our results show that interneuron activity is important in the vascular and metabolic responses during epileptiform discharges. PMID:26745250

  5. Vascular Profile Characterization of Liver Tumors by Magnetic Resonance Imaging Using Hemodynamic Response Imaging in Mice

    Directory of Open Access Journals (Sweden)

    Yifat Edrei

    2011-03-01

    Full Text Available Recently, we have demonstrated the feasibility of using hemodynamic response imaging (HRI, a functional magnetic resonance imaging (MRI method combined with hypercapnia and hyperoxia, for monitoring vascular changes during liver pathologies without the need of contrast material. In this study, we evaluated HRI ability to assess changes in liver tumor vasculature during tumor establishment, progression, and antiangiogenic therapy. Colorectal adenocarcinoma cells were injected intrasplenically to model colorectal liver metastasis (CRLM and the Mdr2 knockout mice were used to model primary hepatic tumors. Hepatic perfusion parameters were evaluated using the HRI protocol and were compared with contrast-enhanced (CE MRI. The hypovascularity and the increased arterial blood supply in well-defined CRLM were demonstrated by HRI. In CRLM-bearing mice, the entire liver perfusion was attenuated as the HRI maps were significantly reduced by 35%. This study demonstrates that the HRI method showed enhanced sensitivity for small CRLM (1–2 mm detection compared with CE-MRI (82% versus 38%, respectively. In addition, HRI could demonstrate the vasculature alteration during CRLM progression (arborized vessels, which was further confirmed by histology. Moreover, HRI revealed the vascular changes induced by rapamycin treatment. Finally, HRI facilitates primary hepatic tumor characterization with good correlation to the pathologic differentiation. The HRI method is highly sensitive to subtle hemodynamic changes induced by CRLM and, hence, can function as an imaging tool for understanding the hemodynamic changes occurring during CRLM establishment, progression, and antiangiogenic treatment. In addition, this method facilitated the differentiation between different types of hepatic lesions based on their vascular profile noninvasively.

  6. Relation between the neuronal and hemodynamic response in the lesioned rat spinal cord following peripheral nerve stimulation

    Science.gov (United States)

    Dubeau, S.; Beaumont, E.; Lesage, F.

    2009-02-01

    In this study, we explore the hemodynamic response in the lesioned rat spinal cord following peripheral nerve stimulation. Oxy and deoxy hemoglobin were measured (using a four color LED multispectral intrinsic optical imaging system) simultaneously with blood flow (laser speckle measurement). Both optical and electrophysiological data are compared spatially and against stimulation strength. When compared with non-lesioned animals, the hemodynamic response is seen to display significant differences exhibiting increased initial dip and decreased blood drain following stimulation. The origin of the difference is observed to be due to the vascular nature of the injury. The distinct hemodynamic responses may have a strong impact on General Linear Model based fMRI studies of spinal cord lesions due to the difficulty in separating vascular effects from neuronal plasticity following injury.

  7. Functional photoacoustic micro-imaging of cerebral hemodynamic changes in single blood vessels after photo-induced brain stroke

    Science.gov (United States)

    Liao, Lun-De; Chen, You-Yin; Lin, Chin-Teng; Li, Meng-Lin

    2013-03-01

    Studying the functional hemodynamic roles of individual cerebral cortical arterioles in maintaining both the structure and function of cortical regions during and after brain stroke in small animals is an important issue. Recently, functional photoacoustic microscopy (fPAM) has been proved as a reliable imaging technique to probe the total hemoglobin concentration (HbT), cerebral blood volume (CBV) and hemoglobin oxygen saturation (SO2) in single cerebral blood vessels of rats. Here, we report the application of fPAM associated with electrophysiology recordings to investigating functional hemodynamic changes in single cortical arterioles of rats with electrical forepaw stimulation after photo-induced ischemic stroke. Because of the weak optical focusing nature of our fPAM system, photo-induced ischemic stroke targeting single cortical arterioles can be easily conducted with simple adaptation. Functional HbT, CBV and SO2 changes associated with the induced stroke in selected arterioles from the anterior cerebral artery system were imaged with 36 x 65-μm spatial resolution. Experimental results showed that after photo-occlusion of a single arteriole, the functional changes of nearby arterioles in cerebral cortex only can be observed immediately after the stroke. After a few minutes of stroke onset, there are no significant functional changes under the forepaw stimulation, suggesting that alternate blood flow routes are not actively recruited. The fPAM with electrophysiology recordings complements existing imaging techniques and has the potential to offer a favorable tool for explicitly studying cerebral hemodynamics in small animal models of photo-indcued ischemic stroke.

  8. Age-related changes in brain hemodynamics; A calibrated MRI study

    DEFF Research Database (Denmark)

    De Vis, J B; Hendrikse, J; Bhogal, A;

    2015-01-01

    INTRODUCTION: Blood oxygenation-level dependent (BOLD) magnetic resonance imaging signal changes in response to stimuli have been used to evaluate age-related changes in neuronal activity. Contradictory results from these types of experiments have been attributed to differences in cerebral blood....... A dual-echo pseudocontinuous arterial spin labeling (ASL) sequence was performed during normocapnic, hypercapnic, and hyperoxic breathing challenges. Whole brain and regional gray matter values of CBF, ASL cerebrovascular reactivity (CVR), BOLD CVR, oxygen extraction fraction (OEF), and CMRO2 were...... could potentially be explained by differences in EtCO2 . Regional CMRO2 was lower in older subjects. BOLD studies should take this into account when investigating age-related changes in neuronal activity....

  9. Brief report: the effects of the menstrual cycle on the hemodynamic response to laryngoscopy and tracheal intubation.

    Science.gov (United States)

    Hanci, Volkan; Yurtlu, Serhan; Hakimoglu, Sedat; Yilmaz, Mensure; Ayoglu, Hilal; Basaran, Mustafa; Erdogan, Gülay; Okyay, Rahsan Dilek; Turan, Isil Ozkoçak

    2010-08-01

    We designed this study to determine the effect of the menstrual cycle on the hemodynamic response to tracheal intubation (TI). Sixty-two ASA I women who were either in the follicular phase (group F, n = 31) or luteal phase (group L, n = 31) of their menstrual cycle were included in the study. Patients received propofol and rocuronium for intubation. Hemodynamic variables were recorded before administration of the IV anesthetic, as well as after TI. Rate pressure products were calculated. Groups were similar in terms of demographic data. Rate pressure products values at the first minute after TI were significantly increased in group L than were those in group F (P < 0.001). We conclude that the phase of the menstrual cycle is an important factor in the hemodynamic response to TI. PMID:20584874

  10. EFFECTS OF ALFENTANIL AND ESMOLOL ON HEMODYNAMIC AND CATECHOLMINE RESPONSE TO TRACHEAL INTUBATION

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Objective.To compare the effects of alfentanil and esmolol on hemodynamic and catecholamine response to tracheal intubation.Methods.hiry-five adult patients were randomly allocated to one of three groups,Grup A(control group),Group B(esmolol group)and Group C(alfentanil group).The patients received either 2 mg/kg esmolol(inGroup B)or 30 μg/kg alfentanil(in GroupC)before intubation.Tracheal intubation was performed with 4 mg/kg thiopental and 0.1 mg/kg vecuronium and 3% isoflurane.Systolic blood pressure(SBP),diastolic blood pressure(BP),mean blood pressure(MBP),heart rate(HR),norepinephrine(NE),epinephrine(E)and dopamine(DA)were measured before and after intubation.Results.The control group had a baeline SBP of 149±23 mmHg while Groups B,C had a baseline SBP of 148±23,and 150±21mmHg,respectively(P>0.05).Three min after tracheal intubation,the control group SBP increased to 160±30 mmHg and Group B remained at the baseline level,14±5 mmHg,and Group C significantly decreased to 91±22 mmHg(P<0.01).Two min after intubation HR in Group B increased significantly but 3 min after intubation HR in Groups B and C were significantly lower than that of contrl group(P<0.05).NE in Groups A and B increased significantly to 5.75±3.51 and 6.75±3.30 nmol/L 3 min after intubation(P<0.01).In Group C,3 min after intubation NE was not significantly differnt from the basline but E decreased significantly(P<0.01).Conclusion.2 ?g/kg esmolol can moerate the hemodynamic response to tracheal intubation to a certain extent and 30μg/kg alfentanil can completely attenuate the hemodynamic and catecholamine responses.

  11. Non-parametric temporal modeling of the hemodynamic response function via a liquid state machine.

    Science.gov (United States)

    Avesani, Paolo; Hazan, Hananel; Koilis, Ester; Manevitz, Larry M; Sona, Diego

    2015-10-01

    Standard methods for the analysis of functional MRI data strongly rely on prior implicit and explicit hypotheses made to simplify the analysis. In this work the attention is focused on two such commonly accepted hypotheses: (i) the hemodynamic response function (HRF) to be searched in the BOLD signal can be described by a specific parametric model e.g., double-gamma; (ii) the effect of stimuli on the signal is taken to be linearly additive. While these assumptions have been empirically proven to generate high sensitivity for statistical methods, they also limit the identification of relevant voxels to what is already postulated in the signal, thus not allowing the discovery of unknown correlates in the data due to the presence of unexpected hemodynamics. This paper tries to overcome these limitations by proposing a method wherein the HRF is learned directly from data rather than induced from its basic form assumed in advance. This approach produces a set of voxel-wise models of HRF and, as a result, relevant voxels are filterable according to the accuracy of their prediction in a machine learning framework. This approach is instantiated using a temporal architecture based on the paradigm of Reservoir Computing wherein a Liquid State Machine is combined with a decoding Feed-Forward Neural Network. This splits the modeling into two parts: first a representation of the complex temporal reactivity of the hemodynamic response is determined by a universal global "reservoir" which is essentially temporal; second an interpretation of the encoded representation is determined by a standard feed-forward neural network, which is trained by the data. Thus the reservoir models the temporal state of information during and following temporal stimuli in a feed-back system, while the neural network "translates" this data to fit the specific HRF response as given, e.g. by BOLD signal measurements in fMRI. An empirical analysis on synthetic datasets shows that the learning process can

  12. Cerebral hemodynamic changes of mild traumatic brain injury at the acute stage.

    Directory of Open Access Journals (Sweden)

    Hardik Doshi

    Full Text Available Mild traumatic brain injury (mTBI is a significant public health care burden in the United States. However, we lack a detailed understanding of the pathophysiology following mTBI and its relation to symptoms and recovery. With advanced magnetic resonance imaging (MRI, we can investigate brain perfusion and oxygenation in regions known to be implicated in symptoms, including cortical gray matter and subcortical structures. In this study, we assessed 14 mTBI patients and 18 controls with susceptibility weighted imaging and mapping (SWIM for blood oxygenation quantification. In addition to SWIM, 7 patients and 12 controls had cerebral perfusion measured with arterial spin labeling (ASL. We found increases in regional cerebral blood flow (CBF in the left striatum, and in frontal and occipital lobes in patients as compared to controls (p = 0.01, 0.03, 0.03 respectively. We also found decreases in venous susceptibility, indicating increases in venous oxygenation, in the left thalamostriate vein and right basal vein of Rosenthal (p = 0.04 in both. mTBI patients had significantly lower delayed recall scores on the standardized assessment of concussion, but neither susceptibility nor CBF measures were found to correlate with symptoms as assessed by neuropsychological testing. The increased CBF combined with increased venous oxygenation suggests an increase in cerebral blood flow that exceeds the oxygen demand of the tissue, in contrast to the regional hypoxia seen in more severe TBI. This may represent a neuroprotective response following mTBI, which warrants further investigation.

  13. EFFECTS OF ALFENTANIL AND ESMOLOL ON HEMODYNAMIC AND CATECHOLAMINE RESPONSE TO TRACHEAL INTUBATION

    Institute of Scientific and Technical Information of China (English)

    龚志毅; 罗爱伦

    1999-01-01

    Objective. To compare the effects of alfentanil and esmolol on hemodynamic and catecholamine responsee to tracheal intubation.Mahods. Thirty-five adult patients were randomly allocated to one of three groups, Group A (control group), Group B (esmolol groap) and Group C (alfentanil group). The patients received either 2 mg/kg esmolol (in Group B) or 30μg/kg alfentanil (in Group C) before intulmtion. Tracheal intubation was performed with 4 mg/kg thiopental and 0. 1 mg/kg vecuronium and 3% isoflurane. Systolic blood pressure(SBP), diastolic blood pressure (DBP), mean blood pressure (MBP), heart rate (HR), norepinephrine(NE),epinephrine(E) and dopamine (DA) were measured before and after intubtttion.Results.The control group had a baseline SBP of 149±23 mmHg while Groups B,C had a baseline SBP of 148±23,and 150±21mmHg,respectively(P>0.05),Three min after tracheal intubation,the control group SBP increased to 160±30mmHg and Group B remained at the baseline level ,147±5mmHg,and Goup C significantly decreased to 91±22mmHg(P<0.01).Two min after intubation HR in Group B increased significantly but 3 min after intubation HR in Groups B and C were significantly lower than that of control group(P<0.05).NE in Groups A and B increased significatly to 5.75±3.51 and 6.75±3.30nmol/L 3 min after intubation(P<0.01).In Group C,3min after intubation NE was not significantly different from the baseline but E becreased significantly(P<0.01).Conclusion.2mg/kg esmolol can moderate the hemodynamic response to tracheal intubation to a certain extent and 30μg/kg alfentanil can completely attenuate the hemodynamic and catecholamine responses.

  14. Hemodynamic response based mixture model to estimate micro- and macro-vasculature contributions in functional MRI

    CERN Document Server

    Singh, Manbir; Sungkarat, Witaya; Zhou, Yongxia

    2003-01-01

    A multi-componet model reflecting the temporal characteristics of micro- and macro-vasculature hemodynamic responses was used to fit the time-course of voxels in functional MRI (fMRI). The number of relevant components, the latency of the first component, the time- separation among the components, their relative amplitude and possible interpretation in terms of partial volume contributions of micro- and macro-components to the time-course data were investigated. Analysis of a reversing checkerboard experiment revealed that there was no improvement in the filing beyond two components. Using a two-component model, the fractional abundances of the micro- and macro-vasculature were estimated in individual voxels. These results suggest the potential of a mixture-model approach to mitigate partial volume effects and separate contributions of vascular components within a voxel in fMRI.

  15. [The effects of premedication on induction doses of propofol and hemodynamic responses during induction].

    Science.gov (United States)

    Kodaka, M; Okamoto, Y; Kakoi, H; Ishizuka, I; Miyao, H; Kawasaki, J; Kawazoe, T

    1997-10-01

    We chose five sedatives for premedication and investigated the effect of these drugs on the induction doses of propofol. One hundred patients were allocated into one of five groups of 20. These groups consisted of control group (C) given only atropine 0.5 mg i.m.; CL group (plus clonidine 0.15 mg orally); H group (plus hydroxyzine 25 mg i.m.); M group (plus midazolam 3 mg i.m.) and D group (plus diazepam 10 mg orally). The induction dose was measured using loss of count technique. Arterial pressure and heart rate were measured, before and after propofol induction as well as after intubation. We also calculated rate pressure products (RPP) at each point. The induction doses were significantly lower in M-group than those in C-group. On the other hand, in hemodynamic responses, RPP was unchanged in any groups after propofol induction and after the intubation. Both propofol and midazolam have been known to have a depressive effect on the central nervous system via GABA-A receptor-mediated inhibition, although the exact receptor for propofol is unknown. We thought, therefore, that when the interaction occurred, both midazolam and propofol had the same effect on the GABA-A receptor and increased chloride ion flux through the channels. Hydroxyzine and clonidine, however, do not share a common receptor or exert effect on the GABA-A receptor. We consider that this was one of the reasons why induction doses of both H and CL group could not decrease significantly. We concluded that midazolam 3 mg decreased propofol induction dose significantly. Both midazolam 3 mg and clonidine 0.15 mg decreased RPP before induction and hemodynamic responses to induction and intubation were stable. PMID:9369050

  16. Hemodynamic changes during neural deactivation in human brain. A positron emission tomography study of crossed cerebellar diaschisis

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Hiroshi; Kanno, Iwao; Shimosegawa, Eku; Tamura, Hajime; Okane, Kumiko; Hatazawa, Jun [Research Inst. for Brain and Blood Vessels, Akita (Japan)

    2002-06-01

    The mechanism of crossed cerebellar diaschisis (CCD) is considered to be secondary hypoperfusion due to neural deactivation. To elucidate the hemodynamics during neural deactivation, the hemodynamics of CCD was investigated. The cerebral blood flow (CBF), cerebral blood volume (CBV), cerebral oxygen extraction fraction (OEF), cerebral metabolic rate of oxygen (CMRO{sub 2}), and vascular responses to hypercapnia and acetazolamide stress for CCD were measured in 20 patients with cerebrovascular disease by positron emission tomography with H{sub 2}{sup 15}O, C{sup 15}O, and {sup 15}O{sub 2}. Vascular responses to hypercapnia and acetazolamide stress were almost the same between CCD side and unaffected side of the cerebellum, a finding that supports the idea that the mechanism of CCD is secondary hypoperfusion due to neural deactivation. The degree of decrease in CBF on the CCD side was almost the same as that in CBV, indicating that vascular blood velocity does not change during neural deactivation. The relation between CBF and CBV of the CCD and unaffected sides was CBV=0.29 CBF{sup 0.56}. On the CCD side, the degree of decrease in CMRO{sub 2} was less than that in CBF, resulting in a significantly increased OEF. The increased OEF along with the decreased CBV on the CCD side might indicate that neural deactivation primarily causes vasoconstriction rather than a reduction of oxygen metabolism. (author)

  17. EFFECT OF PREOPERATIVE INTRAVENOUS CLONIDINE ON HEMODYNAMIC RESPONSE DURING LAPAROSCOPIC SURGERIES

    Directory of Open Access Journals (Sweden)

    Sreeraghu

    2014-02-01

    noticed in the control group. CONCLUSION: From this study, we conclude that int ravenous clonidine 2mcg/kg, given 15 min prior to induction provides stable hemodynamics and protection against stress response to intubation and carbon dioxide insufflation in patients undergoing laparoscopic surgeries. Clonidine provides the added advant ages of reduction in postoperative complications of nausea, vomiting and shivering

  18. Time course of the hemodynamic responses to aortic depressor nerve stimulation in conscious spontaneously hypertensive rats

    Directory of Open Access Journals (Sweden)

    M.T. Durand

    2012-05-01

    Full Text Available The time to reach the maximum response of arterial pressure, heart rate and vascular resistance (hindquarter and mesenteric was measured in conscious male spontaneously hypertensive (SHR and normotensive control rats (NCR; Wistar; 18-22 weeks subjected to electrical stimulation of the aortic depressor nerve (ADN under thiopental anesthesia. The parameters of stimulation were 1 mA intensity and 2 ms pulse length applied for 5 s, using frequencies of 10, 30, and 90 Hz. The time to reach the hemodynamic responses at different frequencies of ADN stimulation was similar for SHR (N = 15 and NCR (N = 14; hypotension = NCR (4194 ± 336 to 3695 ± 463 ms vs SHR (3475 ± 354 to 4494 ± 300 ms; bradycardia = NCR (1618 ± 152 to 1358 ± 185 ms vs SHR (1911 ± 323 to 1852 ± 431 ms, and the fall in hindquarter vascular resistance = NCR (6054 ± 486 to 6550 ± 847 ms vs SHR (4849 ± 918 to 4926 ± 646 ms; mesenteric = NCR (5574 ± 790 to 5752 ± 539 ms vs SHR (5638 ± 648 to 6777 ± 624 ms. In addition, ADN stimulation produced baroreflex responses characterized by a faster cardiac effect followed by a vascular effect, which together contributed to the decrease in arterial pressure. Therefore, the results indicate that there is no alteration in the conduction of the electrical impulse after the site of baroreceptor mechanical transduction in the baroreflex pathway (central and/or efferent in conscious SHR compared to NCR.

  19. Time course of the hemodynamic responses to aortic depressor nerve stimulation in conscious spontaneously hypertensive rats

    International Nuclear Information System (INIS)

    The time to reach the maximum response of arterial pressure, heart rate and vascular resistance (hindquarter and mesenteric) was measured in conscious male spontaneously hypertensive (SHR) and normotensive control rats (NCR; Wistar; 18-22 weeks) subjected to electrical stimulation of the aortic depressor nerve (ADN). The parameters of stimulation were 1 mA intensity and 2 ms pulse length applied for 5 s, using frequencies of 10, 30, and 90 Hz. The time to reach the hemodynamic responses at different frequencies of ADN stimulation was similar for SHR (N = 15) and NCR (N = 14); hypotension = NCR (4194 ± 336 to 3695 ± 463 ms) vs SHR (3475 ± 354 to 4494 ± 300 ms); bradycardia = NCR (1618 ± 152 to 1358 ± 185 ms) vs SHR (1911 ± 323 to 1852 ± 431 ms), and the fall in hindquarter vascular resistance = NCR (6054 ± 486 to 6550 ± 847 ms) vs SHR (4849 ± 918 to 4926 ± 646 ms); mesenteric = NCR (5574 ± 790 to 5752 ± 539 ms) vs SHR (5638 ± 648 to 6777 ± 624 ms). In addition, ADN stimulation produced baroreflex responses characterized by a faster cardiac effect followed by a vascular effect, which together contributed to the decrease in arterial pressure. Therefore, the results indicate that there is no alteration in the conduction of the electrical impulse after the site of baroreceptor mechanical transduction in the baroreflex pathway (central and/or efferent) in conscious SHR compared to NCR

  20. Time course of the hemodynamic responses to aortic depressor nerve stimulation in conscious spontaneously hypertensive rats

    Energy Technology Data Exchange (ETDEWEB)

    Durand, M.T.; Mota, A.L. [Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Barale, A.R. [Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, MG (Brazil); Castania, J.A.; Fazan, R. Jr.; Salgado, H.C. [Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil)

    2012-03-16

    The time to reach the maximum response of arterial pressure, heart rate and vascular resistance (hindquarter and mesenteric) was measured in conscious male spontaneously hypertensive (SHR) and normotensive control rats (NCR; Wistar; 18-22 weeks) subjected to electrical stimulation of the aortic depressor nerve (ADN). The parameters of stimulation were 1 mA intensity and 2 ms pulse length applied for 5 s, using frequencies of 10, 30, and 90 Hz. The time to reach the hemodynamic responses at different frequencies of ADN stimulation was similar for SHR (N = 15) and NCR (N = 14); hypotension = NCR (4194 ± 336 to 3695 ± 463 ms) vs SHR (3475 ± 354 to 4494 ± 300 ms); bradycardia = NCR (1618 ± 152 to 1358 ± 185 ms) vs SHR (1911 ± 323 to 1852 ± 431 ms), and the fall in hindquarter vascular resistance = NCR (6054 ± 486 to 6550 ± 847 ms) vs SHR (4849 ± 918 to 4926 ± 646 ms); mesenteric = NCR (5574 ± 790 to 5752 ± 539 ms) vs SHR (5638 ± 648 to 6777 ± 624 ms). In addition, ADN stimulation produced baroreflex responses characterized by a faster cardiac effect followed by a vascular effect, which together contributed to the decrease in arterial pressure. Therefore, the results indicate that there is no alteration in the conduction of the electrical impulse after the site of baroreceptor mechanical transduction in the baroreflex pathway (central and/or efferent) in conscious SHR compared to NCR.

  1. Near-infrared spectroscopic imaging of stimulus-related hemodynamic responses on the neonatal auditory cortices

    Science.gov (United States)

    Kotilahti, Kalle; Nissila, Ilkka; Makela, Riikka; Noponen, Tommi; Lipiainen, Lauri; Gavrielides, Nasia; Kajava, Timo; Huotilainen, Minna; Fellman, Vineta; Merilainen, Pekka; Katila, Toivo

    2005-04-01

    We have used near-infrared spectroscopy (NIRS) to study hemodynamic auditory evoked responses on 7 full-term neonates. Measurements were done simultaneously above both auditory cortices to study the distribution of speech and music processing between hemispheres using a 16-channel frequency-domain instrument. The stimulation consisted of 5-second samples of music and speech with a 25-second silent interval. In response to stimulation, a significant increase in the concentration of oxygenated hemoglobin ([HbO2]) was detected in 6 out of 7 subjects. The strongest responses in [HbO2] were seen near the measurement location above the ear on both hemispheres. The mean latency of the maximum responses was 9.42+/-1.51 s. On the left hemisphere (LH), the maximum amplitude of the average [HbO2] response to the music stimuli was 0.76+/- 0.38 μ M (mean+/-std.) and to the speech stimuli 1.00+/- 0.45 μ+/- μM. On the right hemisphere (RH), the maximum amplitude of the average [HbO2] response was 1.29+/- 0.85 μM to the music stimuli and 1.23+/- 0.93 μM to the speech stimuli. The results indicate that auditory information is processed on both auditory cortices, but LH is more concentrated to process speech than music information. No significant differences in the locations and the latencies of the maximum responses relative to the stimulus type were found.

  2. Ketamine modulates fetal hemodynamic and endocrine responses to umbilical cord occlusion.

    Science.gov (United States)

    Zarate, Miguel A; Chang, Eileen I; Antolic, Andrew; Wood, Charles E

    2016-09-01

    Umbilical cord occlusion (UCO) is a hypoxic insult that has been used to model birth asphyxia and umbilical cord compression in utero. UCO triggers vigorous neural and endocrine responses that include increased plasma ACTH and cortisol concentrations, increased blood pressure (BP), and decreased heart rate (HR). We have previously reported that ketamine, a noncompetitive N-methyl-D-aspartate receptor antagonist, can modify the fetal hemodynamic and ACTH responses to ventilatory hypoxia and cerebral ischemia-reperfusion. We performed the present experiments to test the hypothesis that ketamine has similar effects on the neuroendocrine and cardiovascular responses to UCO Fetal sheep were chronically catheterized at gestational day 125. Ketamine (3 mg/kg) was administered intravenously to the fetus 10 min prior to the insult. UCO was induced for 30 min by reducing the umbilical vein blood flow until fetal PaO2 levels were reduced from 17 ± 1 to 11 ± 1 mm Hg. UCO produced an initial increase on fetal BP in both control and ketamine groups (P = 0.018 time), followed by a decrease in the control group, but values remained higher with ketamine. HR decreased after UCO (P = 0.041 stimulus*time) in both groups, but the reduction was greater initially in control compared to ketamine groups. Fetal PaCO2 levels increased after UCO (P ketamine groups. UCO significantly decreased fetal pH values (P ketamine group. Ketamine delayed the cortisol responses to UCO (P ketamine augmented the cardiovascular response to UCO, but did not alter the ACTH response to UCO. PMID:27597770

  3. Thermal and hemodynamic response to whole-body cryostimulation in healthy subjects.

    Science.gov (United States)

    Zalewski, Pawel; Klawe, Jacek J; Pawlak, Joanna; Tafil-Klawe, Malgorzata; Newton, Julia

    2013-06-01

    Whole-body cryotherapy (WBC) is an increasing applied cryotherapeutic method, that involves application of a cryotherapeutic factor to stimulate the body by the means of intense hypothermia of virtually the body's entire area. This method is still not well recognized in Western Europe. However in recent years it is becoming increasingly popular in sports medicine and also in clinical application. Cryotherapeutic agents used in WBC are considered to be a strong stress stimulus which is associated with a variety of changes in functional parameters, particularly of the cardiovascular and autonomic nervous systems. However, such strong influence upon the entire body could be associated with the risk of unexpected reactions which might be dangerous for homeostasis. The present study evaluated the complex hemodynamic physiological reactions in response to WBC exposure in healthy subjects. Thirty healthy male volunteers participated. Each subject was exposed to WBC (-120°C) for 3-min. None of the participants had been exposed to such conditions previously. The research was conducted with modern and reliable measurements techniques, which assessed complex hemodynamic reactions and skin temperature changes non-invasively. All measurements were performed four times (before WBC, after WBC, WBC+3h and WBC+6h) with a Task Force Monitor (TFM - CNSystems, Medizintechnik, Gratz, Austria). Body superficial temperature was measured by infrared thermographic techniques - infra-red camera Flir P640 (Flir Systems Inc., Sweden). Our results show a significant decrease in heart rate, cardiac output, and increase in stroke volume, total peripheral resistance and baroreceptors reflex sensitivity. These changes were observed just after WBC exposure. At stages WBC+3h and WBC+6h there was observed a significant drop in baroreceptors reflex sensitivity due to increased thermogenesis. In conclusion, the present findings suggest that WBC strongly stimulates the baroreceptor cardiac reflex in

  4. Hemodynamic and ventilatory response to different levels of hypoxia and hypercapnia in carotid body-denervated rats

    Directory of Open Access Journals (Sweden)

    João Paulo J. Sabino

    2013-01-01

    Full Text Available OBJECTIVE: Chemoreceptors play an important role in the autonomic modulation of circulatory and ventilatory responses to changes in arterial O2 and/or CO2. However, studies evaluating hemodynamic responses to hypoxia and hypercapnia in rats have shown inconsistent results. Our aim was to evaluate hemodynamic and respiratory responses to different levels of hypoxia and hypercapnia in conscious intact or carotid body-denervated rats. METHODS: Male Wistar rats were submitted to bilateral ligature of carotid body arteries (or sham-operation and received catheters into the left femoral artery and vein. After two days, each animal was placed into a plethysmographic chamber and, after baseline measurements of respiratory parameters and arterial pressure, each animal was subjected to three levels of hypoxia (15, 10 and 6% O2 and hypercapnia (10% CO2. RESULTS: The results indicated that 15% O2 decreased the mean arterial pressure and increased the heart rate (HR in both intact (n = 8 and carotid body-denervated (n = 7 rats. In contrast, 10% O2did not change the mean arterial pressure but still increased the HR in intact rats, and it decreased the mean arterial pressure and increased the heart rate in carotid body-denervated rats. Furthermore, 6% O2 increased the mean arterial pressure and decreased the HR in intact rats, but it decreased the mean arterial pressure and did not change the HR in carotid body-denervated rats. The 3 levels of hypoxia increased pulmonary ventilation in both groups, with attenuated responses in carotid body-denervated rats. Hypercapnia with 10% CO2 increased the mean arterial pressure and decreased HR similarly in both groups. Hypercapnia also increased pulmonary ventilation in both groups to the same extent. CONCLUSION: This study demonstrates that the hemodynamic and ventilatory responses varied according to the level of hypoxia. Nevertheless, the hemodynamic and ventilatory responses to hypercapnia did not depend on the

  5. Novel method to classify hemodynamic response obtained using multi-channel fNIRS measurements into two groups: Exploring the combinations of channels

    Directory of Open Access Journals (Sweden)

    Hiroko Ichikawa

    2014-07-01

    Full Text Available Near-infrared spectroscopy (NIRS in psychiatric studies has widely demonstrated that cerebral hemodynamics differs among psychiatric patients. Recently we found that children with attention attention-deficit / hyperactivity disorder (ADHD and children with autism spectrum disorders (ASD showed different hemodynamic responses to their own mother’s face. Based on this finding, we may be able to classify their hemodynamic data into two those groups and predict which diagnostic group an unknown participant belongs to. In the present study, we proposed a novel statistical method for classifying the hemodynamic data of these two groups. By applying a support vector machine (SVM, we searched the combination of measurement channels at which the hemodynamic response differed between the two groups; ADHD and ASD. The SVM found the optimal subset of channels in each data set and successfully classified the ADHD data from the ASD data. For the 24-dimentional hemodynamic data, two optimal subsets classified the hemodynamic data with 84% classification accuracy while the subset contains all 24 channels classified with 62% classification accuracy. These results indicate the potential application of our novel method for classifying the hemodynamic data into two groups and revealing the combinations of channels that efficiently differentiate the two groups.

  6. Association between catechol-O-methyltrasferase Val108/158Met genotype and prefrontal hemodynamic response in schizophrenia.

    Directory of Open Access Journals (Sweden)

    Ryu Takizawa

    Full Text Available BACKGROUND: "Imaging genetics" studies have shown that brain function by neuroimaging is a sensitive intermediate phenotype that bridges the gap between genes and psychiatric conditions. Although the evidence of association between functional val108/158met polymorphism of the catechol-O-methyltransferase gene (COMT and increasing risk for developing schizophrenia from genetic association studies remains to be elucidated, one of the most topical findings from imaging genetics studies is the association between COMT genotype and prefrontal function in schizophrenia. The next important step in the translational approach is to establish a useful neuroimaging tool in clinical settings that is sensitive to COMT variation, so that the clinician could use the index to predict clinical response such as improvement in cognitive dysfunction by medication. Here, we investigated spatiotemporal characteristics of the association between prefrontal hemodynamic activation and the COMT genotype using a noninvasive neuroimaging technique, near-infrared spectroscopy (NIRS. METHODOLOGY/PRINCIPAL FINDINGS: Study participants included 45 patients with schizophrenia and 60 healthy controls matched for age and gender. Signals that are assumed to reflect regional cerebral blood volume were monitored over prefrontal regions from 52-channel NIRS and compared between two COMT genotype subgroups (Met carriers and Val/Val individuals matched for age, gender, premorbid IQ, and task performance. The [oxy-Hb] increase in the Met carriers during the verbal fluency task was significantly greater than that in the Val/Val individuals in the frontopolar prefrontal cortex of patients with schizophrenia, although neither medication nor clinical symptoms differed significantly between the two subgroups. These differences were not found to be significant in healthy controls. CONCLUSIONS/SIGNIFICANCE: These data suggest that the prefrontal NIRS signals can noninvasively detect the impact

  7. Hemodynamic and ADH responses to central blood volume shifts in cardiac-denervated humans

    Science.gov (United States)

    Convertino, V. A.; Thompson, C. A.; Benjamin, B. A.; Keil, L. C.; Savin, W. M.; Gordon, E. P.; Haskell, W. L.; Schroeder, J. S.; Sandler, H.

    1990-01-01

    Hemodynamic responses and antidiuretic hormone (ADH) were measured during body position changes designed to induce blood volume shifts in ten cardiac transplant recipients to assess the contribution of cardiac and vascular volume receptors in the control of ADH secretion. Each subject underwent 15 min of a control period in the seated posture, then assumed a lying posture for 30 min at 6 deg head down tilt (HDT) followed by 20 min of seated recovery. Venous blood samples and cardiac dimensions (echocardiography) were taken at 0 and 15 min before HDT, 5, 15, and 30 min of HDT, and 5, 15, and 30 min of seated recovery. Blood samples were analyzed for hematocrit, plasma osmolality, plasma renin activity (PRA), and ADH. Resting plasma volume (PV) was measured by Evans blue dye and percent changes in PV during posture changes were calculated from changes in hematocrit. Heart rate (HR) and blood pressure (BP) were recorded every 2 min. Results indicate that cardiac volume receptors are not the only mechanism for the control of ADH release during acute blood volume shifts in man.

  8. A COMPARATIVE STUDY OF INTRAVENOUS MAGNESIUM SULFATE AND ESMOLOL IN ATTENUATING HEMODYNAMIC RESPONSE TO LARYNGOSCOPY AND INTUBATION

    Directory of Open Access Journals (Sweden)

    Aasim

    2014-08-01

    Full Text Available : AIMS AND OBJECTIVES: To compare the effect of intravenous Magnesium sulfate and Esmolol in attenuating the hemodynamic response to laryngoscopy and endo-tracheal intubation. METHODS: A prospective study was conducted with sixty ASA (American society of Anesthesiologists grade I and II patients undergoing elective surgery under general anesthesia who were selected to receive Esmolol hydrochloride 1.5 mg/kg or Magnesium sulfate 50 mg/kg randomly. Heart rate and blood pressure recording were done pre-intubation, immediately after intubation and at 2 minutes and 5 minutes after intubation. RESULTS: There was a significant rise in heart rate in Group M as compared to Group E (P<0.05. No significant difference in mean arterial pressure was seen in both groups. CONCLUSION: Esmolol is a better agent to attenuate hemodynamic response to laryngoscopy and intubation than magnesium sulfate as it attenuates the rise in both heart rate and blood pressure.

  9. Localization of Brain Electrical Activity Sources and Hemodynamic Activity Foci during Motor Imagery

    Czech Academy of Sciences Publication Activity Database

    Frolov, A. A.; Húsek, Dušan; Mokienko, O.; Bobrov, P.; Chernikova, L.; Konovalov, R.

    2014-01-01

    Roč. 40, č. 3 (2014), s. 273-283. ISSN 0362-1197 Grant ostatní: GA MŠk(CZ) ED1.1.00/02.0070; GA MŠk(CZ) EE.2.3.20.0073 Institutional support: RVO:67985807 Keywords : brain computer interface * independent component analysis * EEG pattern classification * motor imagery * inverse EEG problem Subject RIV: IN - Informatics, Computer Science

  10. Cerebral hemodynamics of the aging brain: risk of Alzheimer disease and benefit of aerobic exercise

    Directory of Open Access Journals (Sweden)

    Takashi eTarumi

    2014-01-01

    Full Text Available Alzheimer disease (AD and cerebrovascular disease often coexist with advanced age. Mounting evidence indicates that the presence of vascular disease and its risk factors increase the risk of AD, suggesting a potential overlap of the underlying pathophysiological mechanisms. In particular, atherosclerosis, endothelial dysfunction, and stiffening of central elastic arteries have been shown to associate with AD. Currently, there are no effective treatments for the cure and prevention of AD. Vascular risk factors are modifiable via either pharmacological or lifestyle intervention. In this regard, habitual aerobic exercise is increasingly recognized for its benefits on brain structure and cognitive function. Considering the well-established benefits of regular aerobic exercise on vascular health, exercise-related improvements in brain structure and cognitive function may be mediated by vascular adaptations. In this review, we will present the current evidence for the physiological mechanisms by which vascular health alters the structural and functional integrity of the aging brain and how improvements in vascular health, via regular aerobic exercise, potentially benefits cognitive function.

  11. Hemodynamic responses to endotracheal intubation performed with video and direct laryngoscopy in patients scheduled for major cardiac surgery

    OpenAIRE

    Sarkılar, Gamze; Sargın, Mehmet; Sarıtaş, Tuba Berra; Borazan, Hale; Gök, Funda; Kılıçaslan, Alper; Otelcioğlu, Şeref

    2015-01-01

    This study aims to compare the hemodynamic responses to endotracheal intubation performed with direct and video laryngoscope in patients scheduled for cardiac surgery and to assess the airway and laryngoscopic characteristics. One hundred ten patients were equally allocated to either direct Macintosh laryngoscope (n = 55) or indirect Macintosh C-MAC video laryngoscope (n = 55). Systolic, diastolic, and mean arterial pressure, and heart rate were recorded prior to induction anesthesia, and imm...

  12. Attenuation of Hemodynamic Responses to Laryngoscopy and Tracheal Intubation: Propacetamol versus Lidocaine—A Randomized Clinical Trial

    OpenAIRE

    Ali Kord Valeshabad; Omid Nabavian; Keramat Nourijelyani; Hadi Kord; Hossein Vafainejad; Reza Kord Valeshabad; Ali Reza Feili; Mehdi Rezaei; Hamed Darabi; Mohammad Koohkan; Poorya Golbinimofrad; Samira Jafari

    2014-01-01

    The purpose of this study is to assess the effects of propacetamol on attenuating hemodynamic responses subsequent laryngoscopy and tracheal intubation compared to lidocaine. In this randomized clinical trial, 62 patients with the American Anesthesiologists Society (ASA) class I/II who required laryngoscopy and tracheal intubation for elective surgery were assigned to receive propacetamol 2 g/I.V./infusion (group P) or lidocaine 1.5 mg/kg (group L) prior to laryngoscopy. Systolic and diastoli...

  13. A COMPARATIVE STUDY OF INTRAVENOUS MAGNESIUM SULFATE AND ESMOLOL IN ATTENUATING HEMODYNAMIC RESPONSE TO LARYNGOSCOPY AND INTUBATION

    OpenAIRE

    Aasim; Syama Sundara; Venkatesh,

    2014-01-01

    : AIMS AND OBJECTIVES: To compare the effect of intravenous Magnesium sulfate and Esmolol in attenuating the hemodynamic response to laryngoscopy and endo-tracheal intubation. METHODS: A prospective study was conducted with sixty ASA (American society of Anesthesiologists) grade I and II patients undergoing elective surgery under general anesthesia who were selected to receive Esmolol hydrochloride 1.5 mg/kg or Magnesium sulfate 50 mg/kg randomly. Heart rate and blood pres...

  14. Effects of Esmolol on Hemodynamic Responses to Laryngoscopy and Tracheal Intubation in Diabetic Versus Non-Diabetic Patients

    OpenAIRE

    TAŞYÜZ, Taner

    2007-01-01

    Aim: We aimed to investigate the efficiency of esmolol, a short-acting ß-blocker, in preventing the hemodynamic response to laryngoscopy and endotracheal intubation in diabetic patients. Materials and Methods: Eighty diabetic or non-diabetic patients with ASA physical status I-II scheduled for noncardiac surgery were included in this study. They were divided randomly into 4 groups (Non-diabetic control: NDC, Non-diabetic esmolol: NDE, Diabetic control: DC, Diabetic esmolol: DE). Blood gluco...

  15. Hemodynamic response to Interictal Epileptiform Discharges addressed by personalized EEG-fNIRS recordings

    Directory of Open Access Journals (Sweden)

    Giovanni ePellegrino

    2016-03-01

    Full Text Available Objective: We aimed at studying the hemodynamic response (HR to Interictal Epileptic Discharges (IEDs using patient-specific and prolonged simultaneous ElectroEncephaloGraphy (EEG and functional Near InfraRed Spectroscopy (fNIRS recordings. Methods: The epileptic generator was localized using Magnetoencephalography source imaging. fNIRS montage was tailored for each patient, using an algorithm to optimize the sensitivity to the epileptic generator. Optodes were glued using collodion to achieve prolonged acquisition with high quality signal. fNIRS data analysis was handled with no a priori constraint on HR time course, averaging fNIRS signals to similar IEDs. Cluster-permutation analysis was performed on 3D reconstructed fNIRS data to identify significant spatio-temporal HR clusters. Standard (GLM with fixed HRF and cluster-permutation EEG-fMRI analyses were performed for comparison purposes. Results: fNIRS detected HR to IEDs for 8/9 patients. It mainly consisted oxy-hemoglobin increases (7 patients, followed by oxy-hemoglobin decreases (6 patients. HR was lateralized in 6 patients and lasted from 8.5 to 30s. Standard EEG-fMRI analysis detected an HR in 4/9 patients (4/9 without enough IEDs, 1/9 unreliable result. The cluster-permutation EEG-fMRI analysis restricted to the region investigated by fNIRS showed additional strong and non-canonical BOLD responses starting earlier than the IEDs and lasting up to 30s. Conclusions: i EEG-fNIRS is suitable to detect the HR to IEDs and can outperform EEG-fMRI because of prolonged recordings and greater chance to detect IEDs; ii cluster-permutation analysis unveils additional HR features underestimated when imposing a canonical HR function iii the HR is often bilateral and lasts up to 30s.

  16. Time-resolved and spectral-resolved optical imaging to study brain hemodynamics in songbirds

    Science.gov (United States)

    Mottin, Stéphane; Montcel, Bruno; Guillet de Chatellus, Hugues; Ramstein, Stéphane; Vignal, Clémentine; Mathevon, Nicolas

    2011-07-01

    Contrary to the intense debate about brain oxygen dynamics and its uncoupling in mammals, very little is known in birds. In zebra finches, picosecond optical tomography (POT) with a white laser and a streak camera can measure in vivo oxy-hemoglobin (HbO2) and deoxy-hemoglobin (Hb) concentration changes following physiological stimulation (familiar calls and songs). POT demonstrated sufficient sub-micromolar sensitivity to resolve the fast changes in hippocampus and auditory forebrain areas with 250 μm resolution. The time-course is composed of (i) an early 2s-long event with a significant decrease in Hb and HbO2, respectively -0.7 μMoles/L and -0.9 μMoles/L (ii) a subsequent increase in blood oxygen availability with a plateau of HbO2 (+0.3μMoles/L) and (iii) pronounced vasodilatation events immediately following the end of the stimulus. One of the findings of our work is the direct link between the blood oxygen level-dependent (BOLD) signals previously published in birds and our results. Furthermore, the early vasoconstriction event and post-stimulus ringing seem to be more pronounced in birds than in mammals. These results in bird, a tachymetabolic vertebrate with a long lifespan, can potentially yield new insights for example in brain aging.

  17. Difference of cerebral hemodynamics and metabolism between traumatic focal brain injury and diffuse brain injury in recovery process. Positron emission tomographic evaluation

    International Nuclear Information System (INIS)

    We evaluated chronological changes of cerebral hemodynamics and metabolism of four focal brain injured (FBI) patients and four diffuse brain injured (DBI) patients in the chronic stage. We used positron emission tomography (PET) and compared the difference of the mechanism of recovery from neuronal damage between the two groups of subjects. The Glasgow Coma Scale score on admission was 6 to 14 in the FBI patients and 3 or 4 in the DBI patients. In the PET studies we examined regional cerebral blood flow (rCBF) and regional cerebral metabolic rate for oxygen (rCMRO2) in gray matter. We conclude from our observations that rCBF and rCMRO2 values were strikingly different between the lesion area and the remote area in FBI patients, but were very similar in every area of the cerebral gray matter in the group of DBI patients. PET showed a poor recovery pattern in the surrounding area of the contusion in FBI patients. However, it showed an improvement of the rCBF and rCMRO2 values in every area of the DBI patients whose clinical condition had improved. In areas remote from the contusion in FBI patients, the pattern of improvement of the PET values was very similar to that of DBI patients. This finding suggests that patients with FBI had some neuronal damage that was similar to that of DBI patients in remote areas from the contusion. The mechanism concerning the clinical improvement of the DBI patients is considered to involve axonal synaptic plasticity and the degree of clinical improvement to be strongly dependent on the degree of brain stem damage. (author)

  18. Diffuse optical monitoring of hemodynamic changes in piglet brain with closed head injury

    Science.gov (United States)

    Zhou, Chao; Eucker, Stephanie A.; Durduran, Turgut; Yu, Guoqiang; Ralston, Jill; Friess, Stuart H.; Ichord, Rebecca N.; Margulies, Susan S.; Yodh, Arjun G.

    2009-05-01

    We used a nonimpact inertial rotational model of a closed head injury in neonatal piglets to simulate the conditions following traumatic brain injury in infants. Diffuse optical techniques, including diffuse reflectance spectroscopy and diffuse correlation spectroscopy (DCS), were used to measure cerebral blood oxygenation and blood flow continuously and noninvasively before injury and up to 6 h after the injury. The DCS measurements of relative cerebral blood flow were validated against the fluorescent microsphere method. A strong linear correlation was observed between the two techniques (R=0.89, pheart rate. Finally, the diffuse optical techniques demonstrated sensitivity to dynamic physiological events, such as apnea, cardiac arrest, and hypertonic saline infusion. In total, the investigation corraborates potential of the optical methods for bedside monitoring of pediatric and adult human patients in the neurointensive care unit.

  19. Cognition and Hemodynamics

    OpenAIRE

    Novak, Vera

    2012-01-01

    The relationship between cerebral hemodynamics and cognitive performance has increasingly become recognized as a major challenge in clinical practice for older adults. Both diabetes and hypertension worsen brain perfusion and are major risk factors for cerebrovascular disease, stroke and dementia. Cerebrovascular reserve has emerged as a potential biomarker for monitoring pressure–perfusion–cognition relationships. Endothelial dysfunction and inflammation, microvascular disease, and mascrovas...

  20. Reduced dorsolateral prefrontal cortical hemodynamic response in adult obsessive-compulsive disorder as measured by near-infrared spectroscopy during the verbal fluency task

    Directory of Open Access Journals (Sweden)

    Hirosawa R

    2013-07-01

    Full Text Available Rikuei Hirosawa,1 Jin Narumoto,1 Yuki Sakai,1 Seiji Nishida,2 Takuya Ishida,1 Takashi Nakamae,1 Yuichi Takei,3 Kenji Fukui1 1Department of Psychiatry, Graduate School of Medicine, Kyoto Prefectural University of Medicine, Kyoto, 2Maizuru Medical Center, Kyoto, 3Department of Psychiatry and Neuroscience, Gunma University Graduate School of Medicine, Gunma, Japan Background: Near-infrared spectroscopy has helped our understanding of the neurobiological mechanisms of psychiatric disorders and has advantages including noninvasiveness, lower cost, and ease of use compared with other imaging techniques, like functional magnetic resonance imaging. The verbal fluency task is the most common and well established task used to assess cognitive activation during near-infrared spectroscopy. Recent functional neuroimaging studies have shown that the orbitofrontal cortex and other brain regions, including the dorsolateral prefrontal cortex, may play important roles in the pathophysiology of obsessive-compulsive disorder (OCD. This study aimed to evaluate hemodynamic responses in the dorsolateral prefrontal cortex in patients with OCD using near-infrared spectroscopy during the verbal fluency task and to compare these with dorsolateral prefrontal cortex responses in healthy controls. Methods: Twenty patients with OCD and 20 controls matched for age, gender, handedness, and estimated intelligence quotient participated in this study. The verbal fluency task was used to elicit near-infrared spectroscopic activation and consisted of a 30-second pre-task, followed by three repetitions of a 20-second verbal fluency task (total 60 seconds, followed by a 70-second post-task period. The near-infrared spectroscopy experiment was conducted on the same day as surveys of obsessive-compulsive symptoms, depression, and anxiety. Z-scores for changes in the concentration of oxygenated hemoglobin were compared between the OCD patients and controls in 14 channels set over the

  1. The hemodynamic response of the alpha rhythm: an EEG/fMRI study.

    NARCIS (Netherlands)

    J.C. de Munck; S.I. Goncalves; L. Huijboom; J.P. Kuijer; P.J. Pouwels; R.M. Heethaar; F.H. Lopes da Silva

    2007-01-01

    EEG was recorded during fMRI scanning of 16 normal controls in resting condition with eyes closed. Time variations of the occipital alpha band amplitudes were correlated to the fMRI signal variations to obtain insight into the hemodynamic correlates of the EEG alpha activity. Contrary to earlier stu

  2. Comparison of Fentanyl and Fentanyl Plus Lidocaine on Attenuation of Hemodynamic Responses to Tracheal Intubation in Controlled Hypertensive Patients Undergoing General Anesthesia

    OpenAIRE

    Hassani, Valiallah; Movassaghi, Gholamreza; Goodarzi, Vahid; Safari, Saeid

    2013-01-01

    Background Induction of anesthesia and endotracheal intubation often creates a period of hemodynamic instability in hypertensive patients. Endotracheal intubation of the trachea stimulates laryngeal and tracheal sensory receptors, resulting in a marked increase in the elaboration of sympathetic amines. Objectives This trial aimed to evaluate and compare the efficacy of fentanyl and fentanyl plus lidocaine in attenuating the hemodynamic responses to laryngoscopy and endotracheal intubation in ...

  3. Law, Responsibility, and the Brain

    Science.gov (United States)

    Mobbs, Dean; Lau, Hakwan C.; Jones, Owen D.; Frith, Chris D.

    In perhaps the first attempt to link the brain to mental illness, Hippocrates elegantly wrote that it is the brain that makes us mad or delirious. Epitomizing one of the fundamental assumptions of contemporary neuroscience, Hippocrates' words resonate far beyond the classic philosophical puzzle of mind and body and posit that our behavior, no matter how monstrous, lies at the mercy of our brain's integrity. While clinicopathological observations have long pointed to several putative neurobiological systems as important in antisocial and violent criminal behavior, recent advances in brain-imaging have the potential to provide unparalleled insight. Consequently, brain-imaging studies have reinvigorated the neurophilosophical and legal debate of whether we are free agents in control of our own actions or mere prisoners of a biologically determined brain. In this chapter, we review studies pointing to brain dysfunction in criminally violent individuals and address a range of philosophical and practical issues concerning the use of brainimaging in court. We finally lay out several guidelines for its use in the legal system.

  4. Hemodynamic responses in human multisensory and auditory association cortex to purely visual stimulation

    Directory of Open Access Journals (Sweden)

    Baumann Simon

    2007-02-01

    Full Text Available Abstract Background Recent findings of a tight coupling between visual and auditory association cortices during multisensory perception in monkeys and humans raise the question whether consistent paired presentation of simple visual and auditory stimuli prompts conditioned responses in unimodal auditory regions or multimodal association cortex once visual stimuli are presented in isolation in a post-conditioning run. To address this issue fifteen healthy participants partook in a "silent" sparse temporal event-related fMRI study. In the first (visual control habituation phase they were presented with briefly red flashing visual stimuli. In the second (auditory control habituation phase they heard brief telephone ringing. In the third (conditioning phase we coincidently presented the visual stimulus (CS paired with the auditory stimulus (UCS. In the fourth phase participants either viewed flashes paired with the auditory stimulus (maintenance, CS- or viewed the visual stimulus in isolation (extinction, CS+ according to a 5:10 partial reinforcement schedule. The participants had no other task than attending to the stimuli and indicating the end of each trial by pressing a button. Results During unpaired visual presentations (preceding and following the paired presentation we observed significant brain responses beyond primary visual cortex in the bilateral posterior auditory association cortex (planum temporale, planum parietale and in the right superior temporal sulcus whereas the primary auditory regions were not involved. By contrast, the activity in auditory core regions was markedly larger when participants were presented with auditory stimuli. Conclusion These results demonstrate involvement of multisensory and auditory association areas in perception of unimodal visual stimulation which may reflect the instantaneous forming of multisensory associations and cannot be attributed to sensation of an auditory event. More importantly, we are able

  5. Effects of race and sex on cerebral hemodynamics, oxygen delivery and blood flow distribution in response to high altitude

    Science.gov (United States)

    Liu, Jie; Liu, Yang; Ren, Li-Hua; Li, Li; Wang, Zhen; Liu, Shan-Shan; Li, Su-Zhi; Cao, Tie-Sheng

    2016-08-01

    To assess racial, sexual, and regional differences in cerebral hemodynamic response to high altitude (HA, 3658 m). We performed cross-sectional comparisons on total cerebral blood flow (TCBF = sum of bilateral internal carotid and vertebral arterial blood flows = QICA + QVA), total cerebrovascular resistance (TCVR), total cerebral oxygen delivery (TCOD) and QVA/TCBF (%), among six groups of young healthy subjects: Tibetans (2-year staying) and Han (Han Chinese) at sea level, Han (2-day, 1-year and 5-year) and Tibetans at HA. Bilateral ICA and VA diameters and flow velocities were derived from duplex ultrasonography; and simultaneous measurements of arterial pressure, oxygen saturation, and hemoglobin concentration were conducted. Neither acute (2-day) nor chronic (>1 year) responses showed sex differences in Han, except that women showed lower TCOD compared with men. Tibetans and Han exhibited different chronic responses (percentage alteration relative to the sea-level counterpart value) in TCBF (‑17% vs. 0%), TCVR (22% vs. 12%), TCOD (0% vs. 10%) and QVA/TCBF (0% vs. 2.4%, absolute increase), with lower resting TCOD found in SL- and HA-Tibetans. Our findings indicate racial but not sex differences in cerebral hemodynamic adaptations to HA, with Tibetans (but not Han) demonstrating an altitude-related change of CBF distribution.

  6. Effects of race and sex on cerebral hemodynamics, oxygen delivery and blood flow distribution in response to high altitude.

    Science.gov (United States)

    Liu, Jie; Liu, Yang; Ren, Li-Hua; Li, Li; Wang, Zhen; Liu, Shan-Shan; Li, Su-Zhi; Cao, Tie-Sheng

    2016-01-01

    To assess racial, sexual, and regional differences in cerebral hemodynamic response to high altitude (HA, 3658 m). We performed cross-sectional comparisons on total cerebral blood flow (TCBF = sum of bilateral internal carotid and vertebral arterial blood flows = QICA + QVA), total cerebrovascular resistance (TCVR), total cerebral oxygen delivery (TCOD) and QVA/TCBF (%), among six groups of young healthy subjects: Tibetans (2-year staying) and Han (Han Chinese) at sea level, Han (2-day, 1-year and 5-year) and Tibetans at HA. Bilateral ICA and VA diameters and flow velocities were derived from duplex ultrasonography; and simultaneous measurements of arterial pressure, oxygen saturation, and hemoglobin concentration were conducted. Neither acute (2-day) nor chronic (>1 year) responses showed sex differences in Han, except that women showed lower TCOD compared with men. Tibetans and Han exhibited different chronic responses (percentage alteration relative to the sea-level counterpart value) in TCBF (-17% vs. 0%), TCVR (22% vs. 12%), TCOD (0% vs. 10%) and QVA/TCBF (0% vs. 2.4%, absolute increase), with lower resting TCOD found in SL- and HA-Tibetans. Our findings indicate racial but not sex differences in cerebral hemodynamic adaptations to HA, with Tibetans (but not Han) demonstrating an altitude-related change of CBF distribution. PMID:27503416

  7. Flexibly combined optical microangiography and dual-wavelength laser speckle system for comprehensive imaging of hemodynamic and metabolic responses

    Science.gov (United States)

    Shi, Lei; Qin, Jia; An, Lin; Wang, Ruikang K.

    2014-03-01

    We have proposed and developed a multi-modal non-invasive biomedical optical imager. It was combined from the subsystems of optical microangiography and dual-wavelength laser speckle contrast imaging. The system was designed to maintain the performances of both subsystems. It was capable of simultaneously imaging the hemodynamic and metabolic responses in tissue environment in vivo. To achieve such requirements, we utilized unique optical setup, such as paired dichroic mirrors to compensate dispersion, additional relay lens to increase working distance and translational sample probe to freely select imaging area and focal plane. The multi-functionality of the system was demonstrated in an investigation of hemodynamic and metabolic responses on an acute wound healing model in mouse pinna in vivo. The microvasculature, blood flow and hemoglobin concentration from millimeter down to capillary level were comprehensively visualized. The captured instantaneous responses to wound onset differed greatly between localized areas; after that blood flow had a rebalance tendency, and hemoglobin concentration dynamically recovered to baseline situation.

  8. Differences in the Pattern of Hemodynamic Response to Self-Face and Stranger-Face Images in Adolescents with Anorexia Nervosa: A Near-Infrared Spectroscopic Study.

    Directory of Open Access Journals (Sweden)

    Takeshi Inoue

    Full Text Available There have been no reports concerning the self-face perception in patients with anorexia nervosa (AN. The purpose of this study was to compare the neuronal correlates of viewing self-face images (i.e. images of familiar face and stranger-face images (i.e. images of an unfamiliar face in female adolescents with and without AN. We used near-infrared spectroscopy (NIRS to measure hemodynamic responses while the participants viewed full-color photographs of self-face and stranger-face. Fifteen females with AN (mean age, 13.8 years and 15 age- and intelligence quotient (IQ-matched female controls without AN (mean age, 13.1 years participated in the study. The responses to photographs were compared with the baseline activation (response to white uniform blank. In the AN group, the concentration of oxygenated hemoglobin (oxy-Hb significantly increased in the right temporal area during the presentation of both the self-face and stranger-face images compared with the baseline level. In contrast, in the control group, the concentration of oxy-Hb significantly increased in the right temporal area only during the presentation of the self-face image. To our knowledge the present study is the first report to assess brain activities during self-face and stranger-face perception among female adolescents with AN. There were different patterns of brain activation in response to the sight of the self-face and stranger-face images in female adolescents with AN and controls.

  9. Attenuation of Hemodynamic Responses to Intubation by Gabapentin in Coronary Artery Bypass Surgery: a Randomized Clinical Trial.

    Science.gov (United States)

    Marashi, Seyed Mojtaba; Saeedinia, Seyed Mostafa; Sadeghi, Mostafa; Movafegh, Ali; Marashi, Shaqayeq

    2015-12-01

    A varieties of medications have been suggested to prevent hemodynamic instabilities following laryngoscopy and endotracheal intubation. This study was conducted to determine the beneficial effects of gabapentin on preventing hemodynamic instabilities associated with intubation in patients who were a candidate for coronary artery bypass surgery (CABG). This double blinded randomized, parallel group clinical trial was carried out on 58 normotensive patients scheduled for elective CABG under general anesthesia with endotracheal intubation in Shariati Hospital. Patients were randomly allocated to two groups of 29 patients that received 1200 mg of gabapentin in two dosages (600 mg, 8 hours before anesthesia induction and 600 mg, 2 hours before anesthesia induction) as gabapentin group or received talc powder as placebo (placebo group). Heart rate, mean arterial pressure, systolic and diastolic blood pressure were measured immediately before intubation, during intubation, immediately after intubation, 1 and 2 minutes after tracheal intubation. Inter-group comparisons significantly showed higher systolic and diastolic blood pressure, mean arterial pressure and heart rate immediately before intubation, during intubation, immediately after intubation, 1 and 2 minutes after tracheal intubation in the placebo group in comparison to gabapentin group. The median of anxiety verbal analog scale (VAS) at the pre-induction room in gabapentin and placebo groups were 2 and 4, respectively that was significantly lower in the former group (P. value =0.04 ); however, regarding median of pain score no difference was observed between them (P. value =0.07). Gabapentin (1200 mg) given preoperatively can effectively attenuate the hemodynamic response to laryngoscopy, intubation and also reduce preoperative related anxiety in patients who were a candidate for CABG. PMID:26749228

  10. Comparison of hemodynamic and metabolic stress responses caused by endotracheal tube and Proseal laryngeal mask airway in laparoscopic cholecystectomy

    Directory of Open Access Journals (Sweden)

    Handan Güleç

    2012-01-01

    Full Text Available Background: We aimed to compare hemodynamic and endocrine alterations caused by stress response due to Proseal laryngeal mask airway and endotracheal tube usage in laparoscopic cholecystectomy. Materials and Methods: Sixty-three ASA I-II patients scheduled for elective laparoscopic cholecystectomy were included in the study. Patients were randomly allocated into two groups of endotracheal tube and Proseal laryngeal mask airway. Standard general anaesthesia was performed in both groups with the same drugs in induction and maintenance of anaesthesia. After anaesthesia induction and 20 minutes after CO 2 insufflations, venous blood samples were obtained for measuring adrenalin, noradrenalin, dopamine and cortisol levels. Hemodynamic and respiratory parameters were recorded at the 1 st , 5 th , 15 th , 30 th and 45 th minutes after the insertion of airway devices. Results: No statistically significant differences in age, body mass index, gender, ASA physical status, and operation time were found between the groups (p > 0.05. Changes in hemodynamic and respiratory parameters were not statistically significant when compared between and within groups (p > 0.05. Although no statistically significant differences were observed between and within groups when adrenalin, noradrenalin and dopamine values were compared, serum cortisol levels after CO 2 insufflation in PLMA group were significantly lower than the ETT group (p = 0.024. When serum cortisol levels were compared within groups, cortisol levels 20 minutes after CO 2 insufflation were significantly higher (46.1 (9.5-175.7 and 27.0 (8.3-119.4 in the ETT and PLMA groups, respectively than cortisol levels after anaesthesia induction (11.3 (2.8-92.5 and 16.6 (4.4-45.4 in the ETT and PLMA groups, respectively in both groups (p = 0.001. Conclusion: PLMA usage is a suitable, effective and safe alternative to ETT in laparoscopic cholecystectomy patients with lower metabolic stress.

  11. Autoimmune Responses to Brain Following Stroke

    OpenAIRE

    Becker, Kyra

    2012-01-01

    This review provides a synthesis of the work done by our laboratory that demonstrates the presence of cellular immune responses directed towards brain antigens in animals following experimental stroke as well as in patients following ischemic stroke. These responses include both antigenspecific Th1(+) responses, which are associated with worse stroke outcome, and antigen-specific Treg responses, which are associated with better stroke outcome. The likelihood of developing a detrimental Th1(+)...

  12. Dopaminergic drugs in congestive heart failure: hemodynamic and neuroendocrine responses to ibopamine, dopamine, and dihydroergotoxine.

    Science.gov (United States)

    Metra, M; Missale, C; Spano, P F; Cas, L D

    1995-05-01

    Ibopamine has hemodynamic and neurohumoral effects potentially useful for the treatment of congestive heart failure (CHF), but its mechanism of action is not completely clear. To evaluate the role of dopaminergic receptor stimulation in the hemodynamic and neurohumoral activity of ibopamine, we compared the effects of ibopamine, 100 mg orally (p.o.) with those of the dopamine 2, 4, and 6 micrograms/kg/min intravenously (i.v.) and of the DA2 agonist dihydroergotoxine 6 micrograms/kg i.v. in 13 patients with chronic CHF [left ventricular ejection fraction (LVEF) index (CI) with a 23 and 25% increase in stroke volume (SV) and stroke work indexes (SWI), respectively, and an 18% reduction in systemic vascular resistance (SVR). Similar changes were observed after DA infused at the doses of 2 and 4 micrograms/kg/min, whereas with the dose of 6 micrograms/kg/min heart rate (HR) increased by 23% and SV index (SVI) did not change further. Dihydroergotoxine administration induced only a significant 9% decrease in mean arterial pressure (MAP), with a 13% reduction in SVR.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7630152

  13. The effects of healthy aging on cerebral hemodynamic responses to posture change

    International Nuclear Information System (INIS)

    Aging is associated with an increased incidence of orthostatic hypotension, impairment of the baroreceptor reflex and lower baseline cerebral blood flow. The effect of aging on cerebrovascular autoregulation, however, remains to be fully elucidated. We used a novel optical instrument to assess microvascular cerebral hemodynamics in the frontal lobe cortex of 60 healthy subjects ranging from ages 20–78. Diffuse correlation spectroscopy (DCS) and near-infrared spectroscopy (NIRS) were used to measure relative cerebral blood flow (rCBF), total hemoglobin concentration (THC), oxyhemoglobin concentration (HbO2) and deoxyhemoglobin concentration (Hb). Cerebral hemodynamics were monitored for 5 min at each of the following postures: head-of-bed 30°, supine, standing and supine. Supine-to-standing posture change caused significant declines in rCBF, THC and HbO2, and an increase in Hb, across the age continuum (p < 0.01). Healthy aging did not alter postural changes in frontal cortical rCBF (p = 0.23) and was associated with a smaller magnitude of decline in HbO2 (p < 0.05) during supine-to-standing posture change. We conclude that healthy aging does not alter postural changes in frontal cortical perfusion

  14. Different Brain Responses to Pain and Its Expectation in the Dental Chair.

    Science.gov (United States)

    Racek, A J; Hu, X; Nascimento, T D; Bender, M C; Khatib, L; Chiego, D; Holland, G R; Bauer, P; McDonald, N; Ellwood, R P; DaSilva, A F

    2015-07-01

    A dental appointment commonly prompts fear of a painful experience, yet we have never fully understood how our brains react to the expectation of imminent tooth pain once in a dental chair. In our study, 21 patients with hypersensitive teeth were tested using nonpainful and painful stimuli in a clinical setting. Subjects were tested in a dental chair using functional near-infrared spectroscopy to measure cortical activity during a stepwise cold stimulation of a hypersensitive tooth, as well as nonpainful control stimulation on the same tooth. Patients' sensory-discriminative and emotional-cognitive cortical regions were studied through the transition of a neutral to a painful stimulation. In the putative somatosensory cortex contralateral to the stimulus, 2 well-defined hemodynamic peaks were detected in the homuncular orofacial region: the first peak during the nonpainful phase and a second peak after the pain threshold was reached. Moreover, in the upper-left and lower-right prefrontal cortices, there was a significant active hemodynamic response in only the first phase, before the pain. Subsequently, the same prefrontal cortical areas deactivated after a painful experience had been reached. Our study indicates for the first time that pain perception and expectation elicit different hemodynamic cortical responses in a dental clinical setting. PMID:25904140

  15. Hemodynamic variations measured with near-infrared spectroscopy in human forearm muscles in response to venous occlusion: an electrical model

    Science.gov (United States)

    Van Toi, Vo; Hoimes, Matthew L.; Nadgir, Shalini; Fantini, Sergio

    2005-04-01

    We present data collected with near-infrared spectroscopy on the human forearm (brachioradialis muscle) to characterize the hemodynamic response to venous occlusion in muscle. Venous occlusion was achieved in the upper arm by inflating a pneumatic cuff to a pressure of 60 mmHg. We performed absolute measurements of concentration and oxygen saturation of hemoglobin on six healthy adult human subjects. On all six subjects, we consistently found that during a 40-s venous occlusion the hemoglobin concentration increases (by 5.6+/-2.3 μM), while the oxygen saturation of hemoglobin decreases (by 2.1+/-0.7%). This accumulation and desaturation of blood in the forearm in response to the upper arm occlusion can be described with an electrical model in which the charge stored by a capacitor represents the local blood volume, and the electrical current represents blood flow.

  16. Attenuation of Hemodynamic Responses to Laryngoscopy and Tracheal Intubation: Propacetamol versus Lidocaine—A Randomized Clinical Trial

    Science.gov (United States)

    Kord Valeshabad, Ali; Nabavian, Omid; Nourijelyani, Keramat; Kord, Hadi; Vafainejad, Hossein; Kord Valeshabad, Reza; Reza Feili, Ali; Rezaei, Mehdi; Darabi, Hamed; Koohkan, Mohammad; Golbinimofrad, Poorya; Jafari, Samira

    2014-01-01

    The purpose of this study is to assess the effects of propacetamol on attenuating hemodynamic responses subsequent laryngoscopy and tracheal intubation compared to lidocaine. In this randomized clinical trial, 62 patients with the American Anesthesiologists Society (ASA) class I/II who required laryngoscopy and tracheal intubation for elective surgery were assigned to receive propacetamol 2 g/I.V./infusion (group P) or lidocaine 1.5 mg/kg (group L) prior to laryngoscopy. Systolic and diastolic blood pressures (SBP, DBP), mean arterial pressure (MAP), and heart rate (HR) were recorded at baseline, before laryngoscopy and within nine minutes after intubation. In both groups P and L, MAP increased after laryngoscopy and the changes were statistically significant (P Propacetamol 2 gr one hour prior intubation attenuates heart rate responses after laryngoscopy but is not effective to prevent acute alterations in blood pressure after intubation. PMID:24822063

  17. Attenuation of Hemodynamic Responses to Laryngoscopy and Tracheal Intubation: Propacetamol versus Lidocaine-A Randomized Clinical Trial.

    Science.gov (United States)

    Kord Valeshabad, Ali; Nabavian, Omid; Nourijelyani, Keramat; Kord, Hadi; Vafainejad, Hossein; Kord Valeshabad, Reza; Reza Feili, Ali; Rezaei, Mehdi; Darabi, Hamed; Koohkan, Mohammad; Golbinimofrad, Poorya; Jafari, Samira

    2014-01-01

    The purpose of this study is to assess the effects of propacetamol on attenuating hemodynamic responses subsequent laryngoscopy and tracheal intubation compared to lidocaine. In this randomized clinical trial, 62 patients with the American Anesthesiologists Society (ASA) class I/II who required laryngoscopy and tracheal intubation for elective surgery were assigned to receive propacetamol 2 g/I.V./infusion (group P) or lidocaine 1.5 mg/kg (group L) prior to laryngoscopy. Systolic and diastolic blood pressures (SBP, DBP), mean arterial pressure (MAP), and heart rate (HR) were recorded at baseline, before laryngoscopy and within nine minutes after intubation. In both groups P and L, MAP increased after laryngoscopy and the changes were statistically significant (P Propacetamol 2 gr one hour prior intubation attenuates heart rate responses after laryngoscopy but is not effective to prevent acute alterations in blood pressure after intubation. PMID:24822063

  18. Prefrontal hemodynamic responses and the degree of flow experience among occupational therapy students during their performance of a cognitive task

    Directory of Open Access Journals (Sweden)

    Kazuki Hirao

    2014-09-01

    Full Text Available Purpose: Although flow experience is positively associated with motivation to learn, the biological basis of flow experience is poorly understood. Accumulation of evidence on the underlying brain mechanisms related to flow is necessary for a deeper understanding of the motivation to learn. The purpose of this study is to investigate the relationship between flow experience and brain function using near-infrared spectroscopy (NIRS during the performance of a cognitive task. Methods: Sixty right-handed occupational therapy (OT students participated in this study. These students performed a verbal fluency test (VFT while 2-channel NIRS was used to assess changes in oxygenated hemoglobin concentration (oxygenated hemoglobin [oxy-Hb] in the prefrontal cortex. Soon after that, the OT students answered the flow questionnaire (FQ to assess the degree of flow experience during the VFT. Results: Average oxy-Hb in the prefrontal cortex had a significant negative correlation with the satisfaction scores on the FQ. Conclusion: Satisfaction during the flow experience correlated with prefrontal hemodynamic suppression. This finding may assist in understanding motivation to learn and related flow experience.

  19. Quantitative mapping of hemodynamics in the lung, brain, and dorsal window chamber-grown tumors using a novel, automated algorithm

    Science.gov (United States)

    Fontanella, Andrew N.; Schroeder, Thies; Hochman, Daryl W.; Chen, Raymond E.; Hanna, Gabi; Haglund, Michael M.; Secomb, Timothy W.; Palmer, Gregory M.; Dewhirst, Mark W.

    2013-01-01

    Hemodynamic properties of vascular beds are of great interest in a variety of clinical and laboratory settings. However, there presently exists no automated, accurate, technically simple method for generating blood velocity maps of complex microvessel networks. Here we present a novel algorithm that addresses this problem by applying pixel-by-pixel cross-correlation to video data. Temporal signals at every spatial coordinate are compared with signals at neighboring points, generating a series of correlation maps from which speed and direction are calculated. User assisted definition of vessel geometries is not required, and sequential data are analyzed automatically, without user bias. Velocity measurements are validated against the dual-slit method and against capillary flow with known velocities. The algorithm is tested in three different biological models. Along with simultaneously acquired hemoglobin saturation and vascular geometry information, the hemodynamic maps presented here demonstrate an accurate, quantitative method of analyzing dynamic vascular systems. PMID:23781901

  20. Quantitative mapping of hemodynamics in the lung, brain, and dorsal window chamber-grown tumors using a novel, automated algorithm

    OpenAIRE

    Fontanella, Andrew N.; Schroeder, Thies; Hochman, Daryl W.; Chen, Raymond E.; Hanna, Gabi; Haglund, Michael M.; Secomb, Timothy W.; Palmer, Gregory M.; Dewhirst, Mark W.

    2013-01-01

    Hemodynamic properties of vascular beds are of great interest in a variety of clinical and laboratory settings. However, there presently exists no automated, accurate, technically simple method for generating blood velocity maps of complex microvessel networks. Here we present a novel algorithm that addresses this problem by applying pixel-by-pixel cross-correlation to video data. Temporal signals at every spatial coordinate are compared with signals at neighboring points, generating a series...

  1. MR Perfusion-derived Hemodynamic Parametric Response Mapping of Bevacizumab Efficacy in Recurrent Glioblastoma.

    Science.gov (United States)

    Kickingereder, Philipp; Radbruch, Alexander; Burth, Sina; Wick, Antje; Heiland, Sabine; Schlemmer, Heinz-Peter; Wick, Wolfgang; Bendszus, Martin; Bonekamp, David

    2016-05-01

    Purpose To better understand the effect of bevacizumab therapy on tumor blood flow and oxygenation status in patients with recurrent glioblastoma. Materials and Methods Retrospective data evaluation was approved by the local ethics committee of the University of Heidelberg (ethics approval number, S-320/2012), and informed consent was waived. A total of 71 patients who received a diagnosis of recurrent glioblastoma underwent conventional anatomic magnetic resonance (MR) imaging and dynamic susceptibility contrast material-enhanced MR imaging at baseline and at the first follow-up examination after initiation of bevacizumab therapy. Parametric response maps (PRMs) were created with multistep (nonlinear) registration of patients' post- to pretreatment images and voxel-wise subtraction between Gaussian-normalized relative cerebral blood volume (nrCBV) and Gaussian-normalized relative cerebral blood flow (nrCBF) maps. Intratumor voxels were stratified as being increased (PRM[+]) or decreased (PRM[-]) if they exceeded a threshold that represented the 95% confidence interval in the normal-appearing brain. Correlation with progression-free and overall survival was performed with Cox proportional hazards models. Results The risks for disease progression and death significantly increased with (a) higher baseline nrCBV (hazard ratio [HR] = 1.86, P reversal of the biologic behavior and relative prognosis of these tumors does not occur. (©) RSNA, 2015 Online supplemental material is available for this article. PMID:26579564

  2. Noninvasive monitoring hemodynamic responses in RIF tumors during and after PDT

    Science.gov (United States)

    Yu, Guoqiang; Durduran, Turgut; Busch, Theresa M.; Wang, Hsing-Wen; Zhou, Chao; Saunders, H. Mark; Sehgal, Chandra M.; Yodh, Arjun G.

    2003-06-01

    Changes in blood flow and oxygenation during and after PDT provide information about tumor vessel and cellular damage. The characterization of these changes may improve our understanding of PDT mechanisms and help predict treatment efficacy. We have designed a hybrid system that can non-invasively measure in vivo hemodynamic changes and provide independent information about tumor oxygenation and blood flow. Diffuse correlation spectroscopy (DCS) monitors blood flow by measuring the optical phase shifts caused by moving blood cells, while diffuse photon density wave (DPDW) spectroscopy measures tissue absorption and scattering. When mounted on a camera, our unique probe allows non-contact measurements that avoid compressing the tumor and altering blood flow. An optical filter mounted in front of the camera lens cut off light below 650nm, which allowed monitoring of blood flow during PDT. The utility of the hybrid system was demonstrated by monitoring the hemodynamic changes during and after PDT in mice bearing the experimental radiation-induced fibrosarcoma (RIF). For the first time, we non-invasively and continually monitored the in vivo flow changes during PDT. Relative oxygen consumption was calculated using flow values measured by DCS and oxygenation measured by a broadband absorption spectrometer. During PDT an initial rapid increase in blood flow was found, followed by a decrease and slow recovery. After PDT, substantial and continued reductions in blood saturation, blood flow and oxygen consumption were found after 3 hours, suggesting that permanent damage to tumor cells and blood vessels had occurred. The comparison of flow values after PDT as measured by DCS and by Power Doppler ultrasound (CWFA) demonstrated that both techniques non-invasively detected similar global changes in tumor blood flow or perfusion after PDT.

  3. Functional imaging of hemodynamic stimulus response in the rat retina with ultrahigh-speed spectral / Fourier domain OCT

    Science.gov (United States)

    Choi, WooJhon; Baumann, Bernhard; Clermont, Allen C.; Feener, Edward P.; Boas, David A.; Fujimoto, James G.

    2013-03-01

    Measuring retinal hemodynamics in response to flicker stimulus is important for investigating pathophysiology in small animal models of diabetic retinopathy, because a reduction in the hyperemic response is thought to be one of the earliest changes in diabetic retinopathy. In this study, we investigated functional imaging of retinal hemodynamics in response to flicker stimulus in the rat retina using an ultrahigh speed spectral / Fourier domain OCT system at 840nm with an axial scan rate of 244kHz. At 244kHz the nominal axial velocity range that could be measured without phase wrapping was +/-37.7mm/s. Pulsatile total retinal arterial blood flow as a function of time was measured using an en face Doppler approach where a 200μm × 200μm area centered at the central retinal artery was repeatedly raster scanned at a volume acquisition rate of 55Hz. Three-dimensional capillary imaging was performed using speckle decorrelation which has minimal angle dependency compared to other angiography techniques based on OCT phase information. During OCT imaging, a flicker stimulus could be applied to the retina synchronously by inserting a dichroic mirror in the imaging interface. An acute transient increase in total retinal blood flow could be detected. At the capillary level, an increase in the degree of speckle decorrelation in capillary OCT angiography images could also be observed, which indicates an increase in the velocity of blood at the capillary level. This method promises to be useful for the investigation of small animal models of ocular diseases.

  4. The comparison of the effects of dexmedetomidine, fentanyl and esmolol on prevention of hemodynamic response to intubation

    Directory of Open Access Journals (Sweden)

    Nermin Gogus

    2014-09-01

    Full Text Available Background and objectives: Laryngoscopy and intubation can cause hemodynamic response. Various medications may be employed to control that response. In this study, we aimed to compare the effects of dexmedetomidine, fentanyl and esmolol on hemodynamic response. Methods: Ninety elective surgery patients who needed endotracheal intubation who were in American Society of Anesthesiology I–II group and ages between 21 and 65 years were included in that prospective, randomized, double-blind study. Systolic, diastolic, mean arterial pressures, heart rates at the time of admittance at operation room were recorded as basal measurements. The patients were randomized into three groups: Group I (n = 30 received 1 μg/kg dexmedetomidine with infusion in 10 min, Group II (n = 30 received 2 μg/kg fentanyl, Group III received 2 mg/kg esmolol 2 min before induction. The patients were intubated in 3 min. Systolic, diastolic, mean arterial pressures and heart rates were measured before induction, before intubation and 1, 3, 5, 10 min after intubation. Results: When basal levels were compared with the measurements of the groups, it was found that 5 and 10 min after intubation heart rate in Group I and systolic, diastolic, mean arterial pressures in Group III were lower than other measurements (p < 0.05. Conclusions: Dexmedetomidine was superior in the prevention of tachycardia. Esmolol prevented sytolic, diastolic, mean arterial pressure increases following intubation. We concluded that further studies are needed in order to find a strategy that prevents the increase in systemic blood pressure and heart rate both.

  5. Hemodynamic Support in Sepsis

    Directory of Open Access Journals (Sweden)

    Fatih Yildiz

    2014-04-01

    Full Text Available Sepsis is called systemic inflammatory response syndrome due to infection. When added to organs failure and perfusion abnormality is defined in severe sepsis, Hypotension that do not respond to fluid therapy is as defined septic shock. Fluid resuscitation is a most important parts of the treatment in patients with septic shock. Ongoing hypotension that despite of the adequate fluid therapy, vasopressor support initiation is required. Sepsis and septic shock, hemodynamic support is often understood as the hemodynamic support. The different approaches to the development of methods to track and objective comes up. Patients with severe sepsis and septic shock should be follow in the intensive care unit and rapid fluid replacement and effectual hemodynamic support should be provided.

  6. Development a method of clustering multiple functional coupling in hemodynamic disease of the brain with positron emission tomography

    International Nuclear Information System (INIS)

    Aim: We have investigated post operative changes in CBF and vasodilative and vasoconstrictive reactions for an individual patient with cerebrovascular disease (CVD), by means of segmenting the brain image into some clusters with the varied combination of multiple cerebral functions. In this study, we have developed a new method to classify the combination of the multiple functions by using the common mutual information space generated from the PET images for all subjects. Materials and Methods: Four patients with CVD (two Moyamoya disease and two ICA occlusion) underwent PET CBF imaging with [15O] labeled water at conditions of rest, hyper ventilation and acetazolamide loading pre- and post-operation. A mutual information space for all subjects was generated by plotting the values of resting CBF, HV CBF (CBF in hyper ventilation - resting CBF), and AZ CBF (CBF in acetazolamide loading - resting CBF) at the same pixel in the cerebral cortex images for three axes. The space was classified into six segments by hierarchical cluster analysis method. A segmented brain map was created at each study. The characteristic of each segment was described as the mean value of resting CBF, HV and AZ responses as shown in the right side of a figure (no. 6: normal, no. 1: decreased CBF and responses). Results: The segments belonging to the images at pre- and post- operation for each patient are shown in the left of the figure. A closed circle shows a region including operated lesion. In a case 3 with ICA occlusion, the brain map was classified into three segments, that is no. 2 ischemic region with decreased resting CBF and poor vaso-reactivity, no. 6=normal region, no. 5=decreased resting CBF with high vaso-reactivity before operation. Segments of no. 2 turned into no. 3 and no. 4 and segment of no. 5 turned into normal (no. 6) 3 months after operation as shown in arrows of the figure. The map 11 months post operation consists of normal function (no. 6) only. Conclusion: This

  7. Hemodynamic response characteristics of healthy people to changes in meteorological and geomagnetic factors in the north

    Science.gov (United States)

    Zenchenko, T. A.; Varlamova, N. G.

    2015-12-01

    This paper analyzes the influence of variations in meteorological and geomagnetic factors on hemodynamic parameters (HP) in 27 healthy volunteers who are residents of Syktyvkar (daily monitoring of blood pressure (BP) and heart rate (HR) and stroke and cardiac output for the period from December 1, 2003, to December 31, 2004). It is shown that temperature variations and geomagnetic activity level (GMA) make the greatest impact on HP changes (85 and 48% cases, respectively). The BP level increases with decreasing temperature and with increasing levels of GMA. The sensitivity of systolic and diastolic blood pressure to the meteorological and geomagnetic factors is approximately twice as high as the sensitivity of other HP to them. The individual values of seasonal changes in BP parameters are 4-9 mmHg for systolic blood pressure and 3-6 mmHg for diastolic blood pressure. The estimates of the characteristics of meteorological and geomagnetic sensitivity in residents of northern latitudes are in good agreement with the results obtained by us earlier for other climatic zones and geomagnetic conditions, logically complementing and enhancing the common space-time picture of the reactions of the human body to external impacts.

  8. Hemodynamic Responses on Prefrontal Cortex Related to Meditation and Attentional Task

    Directory of Open Access Journals (Sweden)

    Singh eDeepeshwar

    2015-02-01

    Full Text Available Recent neuroimaging studies state that meditation increases regional cerebral blood flow (rCBF in the prefrontal cortex (PFC. The present study employed functional near infrared spectroscopy (fNIRS to evaluate the relative hemodynamic changes in prefrontal cortex during a cognitive task. Twenty-two healthy male volunteers with ages between 18 and 30 years (group mean age ± SD; 22.9 ± 4.6 years performed a color-word stroop task before and after 20 minutes of meditation and random thinking. Repeated measures ANOVA was performed followed by a post-hoc analysis with Bonferroni adjustment for multiple comparisons between the mean values of ‘During’ and ‘Post’ with ‘Pre’ state. During meditation there was an increased in oxy-hemoglobin (∆HbO and total hemoglobin (∆THC concentration with reduced deoxy-hemoglobin (∆HbR concentration over the right prefrontal cortex (rPFC, whereas in random thinking there was increased ∆HbR with reduced total hemoglobin concentration on the rPFC. The mean reaction time was shorter in stroop color word task with reduced ∆THC after meditation, suggestive of improved performance and efficiency in task related to attention. Our findings demonstrated that meditation increased cerebral oxygenation and enhanced performance, which was associated with prefrontal cortex activation.

  9. Magnetic resonance imaging in assessment of treatment response of gamma knife for brain tumors

    Institute of Scientific and Technical Information of China (English)

    GAO Xiao; ZHANG Xue-ning; ZHANG Yun-ting; YU Chun-shui; XU De-sheng

    2011-01-01

    Objective To review the applications of magnetic resonance imaging (MRI) techniques in assessing treatment response to gamma knife radiosurgery for brain tumors.Data sources Published articles about assessing treatment response to gamma knife radiosurgery for brain tumors were selected using PubMed. The search terms were "MRI", "gamma knife" and "brain tumors".Study selection Articles regarding the MRI techniques using for early assessment of treatment response of gamma knife were selected.Results MRI techniques, especially diffusion weighted imaging, perfusion weighted imaging, magnetic resonance spectroscopy, are useful for early assessment of treatment response of gamma knife by detecting the hemodynamic, metabolic, and cellular alterations. Moreover, they can also provide important information on prognosis.Conclusions Diffusion weighted imaging, perfusion weighted imaging and magnetic resonance spectroscopy can provide early assessment of treatment response of gamma knife for brain tumors, and also information of tumor progression or recurrence earlier than conventional MRI. But there are still many questions to be answered which should be based on the development and advancement of MRI and related disciplines.

  10. EFFECT OF ORAL MOXONIDINE IN THE ATTENUATION OF THE HEMODYNAMIC RESPONSES SEEN DURING LAPAROSCOPIC CHOLECYSTECTOMY: A CLINICAL STUDY

    Directory of Open Access Journals (Sweden)

    Raghuram

    2014-04-01

    Full Text Available BACKGROUND: Pneumoperitoneum required for laparoscopic surgeries results in various pathophysiologic changes in the body, especially in the cardiovascular system. Moxonidine is a selective Imidazoline I1-receptor agonist with an I1:α2 affinity ratio of 40:1 to 70:1. Through an action in the Rostral Ventrolateral Medulla (RVLM, where the I1 receptors are situated, it reduces sympathetic outflow and lowers peripheral vascular resistance. BP reduction is not accompanied by any significant change in heart rate or cardiac output. AIMS AND OBJECTIVES: The aim of our study was to evaluate effect of orally administered Moxonidine in attenuating the hemodynamic responses that occur during laparoscopic cholecystectomy. MATERIALS AND METHODS: 50 adult ASA I and II patients scheduled for elective laparoscopic cholecystectomy were selected for this prospective randomized double blinded comparative study. They were randomly allocated to two groups; Moxonidine group and Placebo group. Moxonidine group received oral Moxonidine 0.3 mg at 8 PM the day before surgery and at 8 AM on the day of surgery. Placebo group received a placebo at the same timing as that of the Moxonidine group. RESULTS: When vital parameters were compared significant rise in heart rate, systolic, diastolic and mean blood pressure was noted in the Placebo group following pneumoperitoneum, where as in Moxonidine group the rise was not more than 20% of baseline. CONCLUSION: In conclusion, Moxonidine when administered preoperatively provides perioperative hemodynamic stability in ASA I and II patients undergoing laparoscopic cholecystectomy. It’s other benefits such as absence of reflex tachycardia, preservation of hepatic and renal function makes it a good choice for laparoscopic procedure.

  11. Ultrasound evaluation of obstructive uropathy and its hemodynamic responses in southwest Nigeria

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    I. N. Apoku

    2015-06-01

    Full Text Available ABSTRACTPurpose:To determine the renal arterial hemodynamic changes induced by obstructive uropathy using Doppler ultrasonography.Materials and Methods:60 adult subjects with suspected obstructive uropathy and 60 asymptomatic apparently healthy controls with normal renal ultrasound features were evaluated.B-mode sonography of the kidneys and spectral Doppler examination of the renal interlobar arteries of all the participants were performed. The mean resistive indices (mRI of both interlobar arteries were obtained and compared to that of the controls. The mRI of bilaterally obstructed kidneys were also compared with the mRI of unilaterally obstructed kidneys.Results:The mRI of the right and left kidneys of subjects were 0.72±0.04 and 0.69±0.06 while those of the controls were 0.64±0.04 and 0.63±0.03 respectively. The mRI for the grades of caliectasis increased from grade I (0.72±0.03 to grade II (0.73±0.03 and grade III (0.73±0.02 but fell within the most severe levels of obstruction (0.69±0.07. There was no statistically significant relationship between the grades of caliectasis and unilateral or bilateral obstruction for both kidneys. The results show a sensitivity and specificity of 86.7% and 90% respectively when mRI≥0.7 was used to determine presence of obstruction.Conclusion:Renal duplex sonography is highly sensitive and specific for diagnosis of obstructive uropathy. Increased resistive index of the obstructed kidney may be a useful diagnostic tool in situations where intravenous urography cannot be done or is contraindicated.

  12. Auditory brain-stem responses in syphilis.

    OpenAIRE

    Rosenhall, U; Roupe, G

    1981-01-01

    Analysis of auditory brain-stem electrical responses (BSER) provides an effective means of detecting lesions in the auditory pathways. In the present study the wave patterns were analysed in 11 patients with secondary or latent syphilis with no clinical symptoms referrable to the central nervous system and in two patients with congenital syphilis and general paralysis. Decreased amplitudes and prolonged latencies occurred frequently in patients with secondary and with advanced syphilis. This ...

  13. BRAIN STEM EVOKED RESPONSE AUDIOMETRY A REVIEW

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    Balasubramanian Thiagarajan

    2015-01-01

    Full Text Available Brain stem evoked response audiometry (BERA is a useful objective assessment of hearing. Major advantage of this procedure is its ability to test even infants in whom conventional audiometry may not be useful. This investigation can be used as a screening test for deafness in high risk infants. Early diagnosis and rehabilitation will reduce disability in these children. This article attempts to review the published literature on this subject.

  14. 256-slice whole-brain CT perfusion in assessment of graft reperfusion after surgical revascularization and hemodynamic alterations before and after surgery in Moyamoya disease

    International Nuclear Information System (INIS)

    Objective: To explore the feasibility of 256-slice whole-brain CT perfusion (CTP) in evaluate graft reperfusion after surgical revascularization and hemodynamic alterations before and after surgery in Moyamoya disease. Methods: Twenty-five cases with Moyamoya disease were scanned on a 256-slice CT. CTP was performed pre- and post- surgical revascularization. The volumetric CT angiographic (CTA) images were generated from volumetric data acquired at the arterial phase of CTP. CBF, CBV, TTP and MTT were measured in functional maps at the operated side within middle cerebral artery perfusion areas and contralateral mirroring areas. Relative CBF(rCBF), relative CBV (rCBV), relative TTP (rTTP), relative MTT (rMTT) were also obtained. Differences in perfusion CT values pre- and post operation were assessed with the paired t test or matched-pairs signed-ranks test. Data with normal distribution was present as x±s, while those with the non-normal distribution were present as M (P25-P75). Results: All the direct graft patencies were displayed on volumetric CTA, No significant differences were found between volumetric CTA and conventional CTA. Postoperative CBF, rCBF and rCBV values of the operated side [72.86 (55.54- 112.19) ml · 100 g-1 · min-1, 1.31 (1.05-1.73), 1.45±0.62] were significantly higher than those before operation [46.72 (28.57-57.67) ml · 100 g-1 · min-1, 0.53 (0.33-0.82), 1.01±0.36] (Z= -2.72, -2.98, t=-2.85, P0.05). Conclusion: 256-slice CT has the potential value for the non-invasive assessment of both the graft patency and cerebral hemodynamics changes in Moyamoya disease after surgery with administration of one contrast medium bolus in a single examination. (authors)

  15. Attenuation of Hemodynamic Responses to Laryngoscopy and Tracheal Intubation: Propacetamol versus Lidocaine—A Randomized Clinical Trial

    Directory of Open Access Journals (Sweden)

    Ali Kord Valeshabad

    2014-01-01

    Full Text Available The purpose of this study is to assess the effects of propacetamol on attenuating hemodynamic responses subsequent laryngoscopy and tracheal intubation compared to lidocaine. In this randomized clinical trial, 62 patients with the American Anesthesiologists Society (ASA class I/II who required laryngoscopy and tracheal intubation for elective surgery were assigned to receive propacetamol 2 g/I.V./infusion (group P or lidocaine 1.5 mg/kg (group L prior to laryngoscopy. Systolic and diastolic blood pressures (SBP, DBP, mean arterial pressure (MAP, and heart rate (HR were recorded at baseline, before laryngoscopy and within nine minutes after intubation. In both groups P and L, MAP increased after laryngoscopy and the changes were statistically significant (P<0.001. There were significant changes of HR in both groups after intubation (P<0.02, but the trend of changes was different between two groups (P<0.001. In group L, HR increased after intubation and its change was statistically significant within 9 minutes after intubation (P<0.001, while in group P, HR remained stable after intubation (P=0.8. Propacetamol 2 gr one hour prior intubation attenuates heart rate responses after laryngoscopy but is not effective to prevent acute alterations in blood pressure after intubation.

  16. Frontal hemodynamic responses to high frequency yoga breathing in schizophrenia: A functional near infrared spectroscopy (fNIRS study

    Directory of Open Access Journals (Sweden)

    Hemant eBhargav

    2014-03-01

    Full Text Available Frontal hemodynamic responses to high frequency yoga breathing technique - Kapalabhati (KB was compared between patients of schizophrenia (n =18; 14 males, 4 females and age-gender and education matched healthy subjects (n=18; 14 males, 4 females using functional near-infrared spectroscopy (fNIRS.The diagnosis was confirmed by a psychiatrist using DSM IV. All patients except one received atypical anti-psychotics (one was on typical. They had obtained a stabilized state as evidenced by a steady unchanged medication from their psychiatrist for past 3 months or longer. They learned KB, among other yoga procedures, in the yoga retreat. KB was practiced at the rate of 120 times per minute for 1minute (min. Healthy subjects who were freshly learning yoga too were taught KB. Both the groups had no previous exposure to KB practice and the training was achieved over 2 weeks. A chest pressure transducer was used to monitor the frequency and intensity of the practice objectively. The frontal hemodynamic response in terms of the oxygenated hemoglobin (oxyHb, deoxygenated hemoglobin (deoxyHb and total hemoglobin or blood volume (totalHb concentration was tapped for 5 min before, 1min during and for 5 min after KB.This was obtained in quiet room using a 16 channel functional near-infrared system (FNIR100-ACK-W, BIOPAC Systems, Inc, USA. Average of the eight channels for each side (right and left frontals was obtained for the three sessions. The changes in the levels of oxyHb, deoxyHb and blood volume for the three sessions were compared between the two groups using Independent samples t test.Within group comparison showed that increase in bilateral oxyHb and totalHb from the baseline was highly significant in healthy controls during KB (right oxyHb, p = 0.00; left oxyHb, p= 0.00 and right totalHb, p = 0.01; left totalHb, p = 0.00, whereas schizophrenia patients did not show any significant changes in the same on both the sides. On the other hand

  17. Visfatin induces sickness responses in the brain.

    Directory of Open Access Journals (Sweden)

    Byong Seo Park

    Full Text Available BACKGROUND/OBJECTIVE: Visfatin, also known as nicotiamide phosphoribosyltransferase or pre-B cell colony enhancing factor, is a pro-inflammatory cytokine whose serum level is increased in sepsis and cancer as well as in obesity. Here we report a pro-inflammatory role of visfatin in the brain, to mediate sickness responses including anorexia, hyperthermia and hypoactivity. METHODOLOGY: Rats were intracerebroventricularly (ICV injected with visfatin, and changes in food intake, body weight, body temperature and locomotor activity were monitored. Real-time PCR was applied to determine the expressions of pro-inflammatory cytokines, proopiomelanocortin (POMC and prostaglandin-synthesizing enzymes in their brain. To determine the roles of cyclooxygenase (COX and melanocortin in the visfatin action, rats were ICV-injected with visfatin with or without SHU9119, a melanocortin receptor antagonist, or indomethacin, a COX inhibitor, and their sickness behaviors were evaluated. PRINCIPAL FINDINGS: Administration of visfatin decreased food intake, body weight and locomotor activity and increased body temperature. Visfatin evoked significant increases in the levels of pro-inflammatory cytokines, prostaglandin-synthesizing enzymes and POMC, an anorexigenic neuropeptide. Indomethacin attenuated the effects of visfatin on hyperthermia and hypoactivity, but not anorexia. Further, SHU9119 blocked visfatin-induced anorexia but did not affect hyperthermia or hypoactivity. CONCLUSIONS: Visfatin induced sickness responses via regulation of COX and the melanocortin pathway in the brain.

  18. The acute effects of the thermogenic supplement Meltdown on energy expenditure, fat oxidation, and hemodynamic responses in young, healthy males

    Directory of Open Access Journals (Sweden)

    Cooke Matt

    2008-12-01

    post-exercise states without any adverse hemodynamic responses associated with maximal exercise.

  19. Hemodynamic Support in Sepsis

    OpenAIRE

    Fatih Yildiz; Emre Karakoc

    2014-01-01

    Sepsis is called systemic inflammatory response syndrome due to infection. When added to organs failure and perfusion abnormality is defined in severe sepsis, Hypotension that do not respond to fluid therapy is as defined septic shock. Fluid resuscitation is a most important parts of the treatment in patients with septic shock. Ongoing hypotension that despite of the adequate fluid therapy, vasopressor support initiation is required. Sepsis and septic shock, hemodynamic support is often under...

  20. Impaired hemodynamic response to mental stress in subjects with prehypertension is improved after a single bout of maximal dynamic exercise

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    Renata Frauches Medeiros

    2011-01-01

    Full Text Available INTRODUCTION: High blood pressure during mental stress in subjects with prehypertension is associated with blunted vasodilation in skeletal muscles, which might be improved by an acute bout of exercise. OBJECTIVE: To investigate the hemodynamic responses to mental stress before and after a bout of exercise in subjects with prehypertension. METHOD: Eighteen subjects with prehypertension and 16 with normotension underwent a mental stress test before and after a maximal cardiopulmonary exercise test on a treadmill. Blood pressure was measured by auscultation, and forearm blood flow was measured by venous occlusion plethysmography; from these measurements, the vascular conductance was calculated. RESULTS: Subjects with prehypertension had a higher mean blood pressure during mental stress (prehypertension 112±2 vs. normotension 101±3 mm Hg, p<0.05, and their vascular conductance did not increase (baseline 0.025±0.004 vs. mental stress 0.022±0.003 a.u., p.0.05. After the exercise bout, the mean blood pressure during mental stress was lower in subjects with prehypertension (before exercise 112±2 vs. after exercise 107±2 mm Hg, p<0.05, and vascular conductance increased (baseline 0.011±0.001 vs. mental stress 0.024±0.004 a.u., p<0.05. CONCLUSION: Subjects with prehypertension had elevated blood pressure and a blunted vasodilator response during mental stress, but their blood pressure was attenuated and their vasodilator response was normalized after a single bout of maximal dynamic exercise.

  1. Hemodynamic responses and upper airway morbidity following tracheal intubation in patients with hypertension: Conventional laryngoscopy versus an intubating laryngeal mask airway

    OpenAIRE

    Elif Bengi Sener; Emre Ustun; Burcu Ustun; Binnur Sarihasan

    2012-01-01

    OBJECTIVES: We compared hemodynamic responses and upper airway morbidity following tracheal intubation via conventional laryngoscopy or intubating laryngeal mask airway in hypertensive patients. METHODS: Forty-two hypertensive patients received a conventional laryngoscopy or were intubated with a intubating laryngeal mask airway. Anesthesia was induced with propofol, fentanyl, and cis-atracurium. Measurements of systolic and diastolic blood pressures, heart rate, rate pressure product, and ST...

  2. Comparison of bolus and continuous infusion of esmolol on hemodynamic response to laryngoscopy, endotracheal intubation and sternotomy in coronary artery bypass graft

    OpenAIRE

    Esra Mercanooglu Efe; Basak Atabey Bilgin; Zekeriyya Alanoglu; Murat Akbaba; Cigdem Denker

    2014-01-01

    BACKGROUND AND OBJECTIVE: The aim of this randomized, prospective and double blinded study is to investigate effects of different esmolol use on hemodynamic response of laryngoscopy, endotracheal intubation and sternotomy in coronary artery bypass graft surgery. METHODS: After approval of local ethics committee and patients' written informed consent, 45 patients were randomized into three groups equally. In Infusion Group; from 10 min before intubation up to 5th minute after sternotomy, ...

  3. The effect of different doses of esmolol on hemodynamic, bispectral index and movement response during orotracheal intubation: prospective, randomized, double-blind study

    OpenAIRE

    Mensure Yılmaz Çakırgöz; Aydın Taşdöğen; Çimen Olguner; Hülya Korkmaz; Ertuğrul Öğün; Burak Küçükebe; Esra Duran

    2014-01-01

    Objective: A prospective, randomized and double-blind study was planned to identify the optimum dose of esmolol infusion to suppress the increase in bispectral index values and the movement and hemodynamic responses to tracheal intubation. Materials and methods: One hundred and twenty patients were randomly allocated to one of three groups in a double-blind fashion. 2.5 mg kg-1 propofol was administered for anesthesia induction. After loss of consciousness, and before administration of 0.6 ...

  4. Brain Activity in Response to Visual Symmetry

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    Marco Bertamini

    2014-12-01

    Full Text Available A number of studies have explored visual symmetry processing by measuring event related potentials and neural oscillatory activity. There is a sustained posterior negativity (SPN related to the presence of symmetry. There is also functional magnetic resonance imaging (MRI activity in extrastriate visual areas and in the lateral occipital complex. We summarise the evidence by answering six questions. (1 Is there an automatic and sustained response to symmetry in visual areas? Answer: Yes, and this suggests automatic processing of symmetry. (2 Which brain areas are involved in symmetry perception? Answer: There is an extended network from extrastriate areas to higher areas. (3 Is reflection special? Answer: Reflection is the optimal stimulus for a more general regularity-sensitive network. (4 Is the response to symmetry independent of view angle? Answer: When people classify patterns as symmetrical or random, the response to symmetry is view-invariant. When people attend to other dimensions, the network responds to residual regularity in the image. (5 How are brain rhythms in the two hemispheres altered during symmetry perception? Answer: Symmetry processing (rather than presence produces more alpha desynchronization in the right posterior regions. Finally, (6 does symmetry processing produce positive affect? Answer: Not in the strongest sense, but behavioural measures reveal implicit positive evaluation of abstract symmetry.

  5. Comparison of the efficacy of dexmedetomidine and esmolol in the treatment of increased hemodynamic response during the recovery period

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    Ayşe Neslihan Bebek

    2012-03-01

    Full Text Available Objectives: Our aim was to compare effectiveness of esmololand dexmedetomidine in the treatment of increasedhemodynamic response during anesthesia recovery period.Materials and methods: 60 ASA I-II patients whomscheduled for elective surgery with endotracheal intubationwere randomized before extubation according to theirhemodynamic parameters that were increased 20% oftheir baseline values in order to receive 1mg/kg esmolol(Group Esmolol, n= 30 or 0.5 μg/kg dexmedetomidine(Group Dexmedetomidine, n= 30. Heart rate (HR, systolicand diastolic blood pressures (SBP,DBP, peripheral oxygensaturation (SpO2, end tidal carbon dioxide (ETCO2values, extubation time, recovery time were recorded. Theduration till having pain requiring analgesic was recordedand cognitive functions were evaluated with short memoryorientation concentration test at 20th and 50th minutes.Results: After drug, HR reductions were significant at allperiods in group Dexmedetomidine (Z2-Z10: p<0.001,Z11:p=0.001, Z12, p=0.006. In group DexmedetomidineSBP value was high at 3rd min after drug (p<0.001, andSBP values were lower in all periods before and after extubation(Z6- Z10: p<0.001, Z11: p=0.02, Z12: p=0.04.In group Dexmedetomidine DBP value was higher at 1stmin after drug (p=0.001, DBP values were lower at 10thmin after drug and before extubation (p= 0.045, p=0.001.The duration of pain requiring analgesic and recoveryperiod were longer in dexmedetomidine group (p<0.001,p<0.001.Conclusions: Although esmolol and dexmedetotimidineattenuated hemodynamic response during recovery period,dexmedetotimidine was more effective in hemodynamicstabilization and the duration of pain requiring analgesicwas longer. Esmolol provided faster recovery time. JClin Exp Invest 2012; 3(1: 53-60

  6. Promoting Motor Function by Exercising the Brain

    OpenAIRE

    Stephane Perrey

    2013-01-01

    Exercise represents a behavioral intervention that enhances brain health and motor function. The increase in cerebral blood volume in response to physical activity may be responsible for improving brain function. Among the various neuroimaging techniques used to monitor brain hemodynamic response during exercise, functional near-infrared spectroscopy could facilitate the measurement of task-related cortical responses noninvasively and is relatively robust with regard to the subjects’ motion. ...

  7. Effects of forearm bier block with bretylium on the hemodynamic and metabolic responses to handgrip

    Science.gov (United States)

    Lee, F.; Shoemaker, J. K.; McQuillan, P. M.; Kunselman, A. R.; Smith, M. B.; Yang, Q. X.; Smith, H.; Gray, K.; Sinoway, L. I.

    2000-01-01

    We tested the hypothesis that a reduction in sympathetic tone to exercising forearm muscle would increase blood flow, reduce muscle acidosis, and attenuate reflex responses. Subjects performed a progressive, four-stage rhythmic handgrip protocol before and after forearm bier block with bretylium as forearm blood flow (Doppler) and metabolic (venous effluent metabolite concentration and (31)P-NMR indexes) and autonomic reflex responses (heart rate, blood pressure, and sympathetic nerve traffic) were measured. Bretylium inhibits the release of norepinephrine at the neurovascular junction. Bier block increased blood flow as well as oxygen consumption in the exercising forearm (P bier block (6.41 +/- 0.08 vs. 6.20 +/- 0.06; P bier block. The results support the conclusion that sympathetic stimulation to muscle during exercise not only limits muscle blood flow but also appears to limit anaerobiosis and H(+) release, presumably through a preferential recruitment of oxidative fibers.

  8. Effects of forearm bier block with bretylium on the hemodynamic and metabolic responses to handgrip

    Science.gov (United States)

    Lee, F.; Shoemaker, J. K.; McQuillan, P. M.; Kunselman, A. R.; Smith, M. B.; Yang, Q. X.; Smith, H.; Gray, K.; Sinoway, L. I.

    2000-01-01

    We tested the hypothesis that a reduction in sympathetic tone to exercising forearm muscle would increase blood flow, reduce muscle acidosis, and attenuate reflex responses. Subjects performed a progressive, four-stage rhythmic handgrip protocol before and after forearm bier block with bretylium as forearm blood flow (Doppler) and metabolic (venous effluent metabolite concentration and (31)P-NMR indexes) and autonomic reflex responses (heart rate, blood pressure, and sympathetic nerve traffic) were measured. Bretylium inhibits the release of norepinephrine at the neurovascular junction. Bier block increased blood flow as well as oxygen consumption in the exercising forearm (P blood flow but also appears to limit anaerobiosis and H(+) release, presumably through a preferential recruitment of oxidative fibers.

  9. Landiolol reduces hemodynamic responses to bronchoscopy-assisted suctioning in intubated ICU patients

    OpenAIRE

    Tochikubo, Junpei; Adachi, Yushi U.; Ejima, Tadashi; Numaguchi, Atsushi; Matsuda, Naoyuki; Sato, Shigehito; Shiiya, Norihiko

    2014-01-01

    Landiolol is an ultra-short-acting β1-selective antagonist developed in Japan that was recently approved for the treatment of tachycardia in intensive care units (ICUs). This study investigated the protective effects of landiolol against the cardiovascular responses during bronchoscopic endotracheal suctioning. This study enrolled 15 patients requiring orotracheal intubation in an ICU. All of the patients required endotracheal suctioning using fiber bronchoscopy while sedated at a Ramsay Scal...

  10. Efficacy of esmolol administration at different time intervals in attenuating hemodynamic response to tracheal intubation

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    S K Singhal

    2010-01-01

    Full Text Available Background: Laryngoscopy and endotracheal intubation are known to cause increase in both arterial blood pressure and heart rate. Several strategies have been evolved to blunt the haemodynamic response to tracheal intubation but each method has its own advantages and disadvantages. Esmolol, a cardio selective Beta -1 blocking drug, can alleviate some of these problems. Esmolol, when administered parenterally, exhibits rapid onset and a short duration of action due to its rapid clearance by red blood cell esterases. Hence we conducted the present study to evaluate the efficacy and optimum time of single bolus esmolol administration in attenuating hypertensive- tachycardiac response to laryngoscopy and tracheal intubation. Materials and Methods: The randomized double blind prospective study was conducted in 60 patients, in the age group of 20-40 years, of both sexes, belonging to American Society of Anaesthesiologists (ASA physical status class I or II and scheduled for elective surgery requiring endotracheal intubation and general anaesthesia. The efficacy and optimum time of single bolus esmolol administration in attenuating hypertensive - tachycardiac response to laryngoscopy and tracheal intubation was evaluated. Patients in group I (n=20 received bolus administration of injection esmolol 1.5 mg/kg intravenously (iv 90 seconds before intubation; in group II (n=20 three minutes before intubation and in group III (n=20 six minutes before intubation. Results: There was no clinical and statistically significant variation in heart rate in group I and II at different time intervals of the study period but in group III heart rate increased significantly one minute after tracheal intubation. (P0.05 Conclusion: To conclude, single intravenous bolus dose of esmolol (1.5 mg/kg is safe and more effective in attenuating haemodynamic response to laryngoscopy and tracheal intubation when administered three minutes prior to intubation.

  11. Hemodynamic profile, responsiveness to anandamide, and baroreflex sensitivity of mice lacking fatty acid amide hydrolase

    OpenAIRE

    Pacher, Pál; Bátkai, Sándor; Osei-Hyiaman, Douglas; Offertáler, László; Liu, Jie; Harvey-White, Judy; Brassai, Attila; Járai, Zoltán; Cravatt, Benjamin F.; Kunos, George

    2005-01-01

    The endocannabinoid anandamide exerts neurobehavioral, cardiovascular, and immune-regulatory effects through cannabinoid receptors (CB). Fatty acid amide hydrolase (FAAH) is an enzyme responsible for the in vivo degradation of anandamide. Recent experimental studies have suggested that targeting the endocannabinergic system by FAAH inhibitors is a promising novel approach for the treatment of anxiety, inflammation, and hypertension. In this study, we compared the cardiac performance of FAAH k...

  12. Efficacy of esmolol administration at different time intervals in attenuating hemodynamic response to tracheal intubation

    OpenAIRE

    S.K. Singhal; Naveen Malhotra; Kiranpreet Kaur; Dharmender Dhaiya

    2010-01-01

    Background: Laryngoscopy and endotracheal intubation are known to cause increase in both arterial blood pressure and heart rate. Several strategies have been evolved to blunt the haemodynamic response to tracheal intubation but each method has its own advantages and disadvantages. Esmolol, a cardio selective Beta -1 blocking drug, can alleviate some of these problems. Esmolol, when administered parenterally, exhibits rapid onset and a short duration of action due to its rapid clearance by red...

  13. The effects of dexmedetomidine on hemodynamic responses to tracheal ntubation in hypertensive patients: A comparison with esmolol and sufentanyl

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    Hale Yarkan Uysal

    2012-01-01

    Full Text Available Background: Hypertension and tachycardia caused by tracheal intubation can be detrimental in hypertensive patients. This study was conducted in order to compare the effects of dexmedetomidine on hemodynamic response to tracheal intubation in hypertensive patients with esmolol and sufentanyl. Methods: Sixty hypertensive patients scheduled for noncardiac surgery under general anesthesia were randomly as-signed to receive one of the three drugs before induction of anesthesia. Groups I, II, and III respectively received esmo-lol (100 mg dexmedetomidine (1 μg/kg and sufentanyl (0.25 μg/kg. Heart Rate (HR, systolic (SAP and diastolic (DAP arterial pressures were recorded before drug administration (baseline; T1, after drug administration (T2, after induction of anesthesia (T3, immediately after intubation (T4 and 3, 5 and 10 minutes after intubation (T5, T6, and T7, respectively. The mean percentage variations from T1 to T4 were calculated for all variables (HR, SAP and DAP. Thiopental dose, onset time of vecuronium and intubation time were also assessed. Results: No differences were observed between the three groups regarding demographic data (p > 0.05. Median thi-opental dose was significantly lower in Group II (325 mg; range: 250-500 compared to Group I (425 mg; range: 325-500; p < 0.01 and Group III (375 mg; range: 275-500; p = 0.02. The onset time of vecuronium was longest in Group I (245.2 ± 63 s vs. 193.9 ± 46.6 s and 205.5 ± 43.5 s; p < 0.01 and p < 0.05. In Group I, HR significantly decreased after drug administration compared to baseline (83.8 ± 20.4 vs. 71.7 ± 14.8; p = 0.002. Compared to the baseline (90.4 ± 8.4, DAP decreased after induction and remained below baseline values at T5, T6 and T7 (71.3 ± 12.8, 76.2 ± 10.7, 68.9 ± 10.8 and 62.1 ± 8.7, respectively; p < 0.05 in Group II. According to the mean percen-tage variation, a significant reduction in HR was assessed in Group II compared to Group III (-13.4 ± 17.6% vs. 11

  14. Sympathetic Neural and Hemodynamic Responses During Cold Pressor Test in Elderly Blacks and Whites.

    Science.gov (United States)

    Okada, Yoshiyuki; Jarvis, Sara S; Best, Stuart A; Edwards, Jeffrey G; Hendrix, Joseph M; Adams-Huet, Beverley; Vongpatanasin, Wanpen; Levine, Benjamin D; Fu, Qi

    2016-05-01

    The sympathetic response during the cold pressor test (CPT) has been reported to be greater in young blacks than whites, especially in those with a family history of hypertension. Because blood pressure (BP) increases with age, we evaluated whether elderly blacks have greater sympathetic activation during CPT than age-matched whites. BP, heart rate, cardiac output, and muscle sympathetic nerve activity were measured during supine baseline, 2-minute CPT, and 3-minute recovery in 47 elderly (68±7 [SD] years) volunteers (12 blacks and 35 whites). Baseline BP, heart rate, cardiac output, or muscle sympathetic nerve activity did not differ between races. Systolic and diastolic BP and heart rate increased during CPT (allP0.05). Cardiac output increased during CPT and ≤30 s of recovery in both groups, but was lower in blacks than whites. Muscle sympathetic nerve activity increased during CPT in both groups (bothPvasoconstriction in elderly blacks. PMID:27021009

  15. Imaging the impact of cortical microcirculation on synaptic structure and sensory-evoked hemodynamic responses in vivo.

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    Shengxiang Zhang

    2007-05-01

    Full Text Available In vivo two-photon microscopy was used to image in real time dendrites and their spines in a mouse photothrombotic stroke model that reduced somatosensory cortex blood flow in discrete regions of cortical functional maps. This approach allowed us to define relationships between blood flow, cortical structure, and function on scales not previously achieved with macroscopic imaging techniques. Acute ischemic damage to dendrites was triggered within 30 min when blood flow over >0.2 mm(2 of cortical surface was blocked. Rapid damage was not attributed to a subset of clotted or even leaking vessels (extravasation alone. Assessment of stroke borders revealed a remarkably sharp transition between intact and damaged synaptic circuitry that occurred over tens of mum and was defined by a transition between flowing and blocked vessels. Although dendritic spines were normally ~13 microm from small flowing vessels, we show that intact dendritic structure can be maintained (in areas without flowing vessels by blood flow from vessels that are on average 80 microm away. Functional imaging of intrinsic optical signals associated with activity-evoked hemodynamic responses in somatosensory cortex indicated that sensory-induced changes in signal were blocked in areas with damaged dendrites, but were present ~400 microm away from the border of dendritic damage. These results define the range of influence that blood flow can have on local cortical fine structure and function, as well as to demonstrate that peri-infarct tissues can be functional within the first few hours after stroke and well positioned to aid in poststroke recovery.

  16. Electromyographic, cerebral and muscle hemodynamic responses during intermittent, isometric contractions of the biceps brachii at three submaximal intensities

    Directory of Open Access Journals (Sweden)

    Jui-LinFan

    2014-06-01

    Full Text Available This study examined the electromyographic, cerebral and muscle hemodynamic responses during intermittent isometric contractions of biceps brachii at 20%, 40% and 60% of maximal voluntary contraction (MVC. Eleven volunteers completed two minutes of intermittent isometric contractions (12/min at an elbow angle of 90° interspersed with three minutes rest between intensities in systematic order. Surface electromyography (EMG was recorded from the right biceps brachii and near infrared spectroscopy (NIRS was used to simultaneously measure left prefrontal and right biceps brachii oxyhemoglobin (HbO2, deoxyhemoglobin (HHb and total hemoglobin (Hbtot. Transcranial Doppler ultrasound was used to measure middle cerebral artery velocity (MCAv bilaterally. Finger photoplethysmography was used to record beat-to-beat blood pressure and heart rate. EMG increased with force output from 20% to 60% MVC (P0.05. MCAv increased from rest to exercise but was not different among intensities (P>0.05. Force output correlated with the root mean square EMG and changes in muscle HbO2 (P0.05 at all three intensities. Force output declined by 8% from the 1st to the 24th contraction only at 60% MVC and was accompanied by systematic increases in RMS, cerebral HbO2 and Hbtot with a levelling off in muscle HbO2 and Hbtot. These changes were independent of alterations in mean arterial pressure. Since cerebral blood flow and oxygenation were elevated at 60% MVC, we attribute the development of fatigue to reduced muscle oxygen availability rather than impaired central n

  17. Effect of parameter variations on the hemodynamic response under rotary blood pump assistance.

    Science.gov (United States)

    Lim, Einly; Dokos, Socrates; Salamonsen, Robert F; Rosenfeldt, Franklin L; Ayre, Peter J; Lovell, Nigel H

    2012-05-01

    Numerical models, able to simulate the response of the human cardiovascular system (CVS) in the presence of an implantable rotary blood pump (IRBP), have been widely used as a predictive tool to investigate the interaction between the CVS and the IRBP under various operating conditions. The present study investigates the effect of alterations in the model parameter values, that is, cardiac contractility, systemic vascular resistance, and total blood volume on the efficiency of rotary pump assistance, using an optimized dynamic heart-pump interaction model previously developed in our laboratory based on animal experimental measurements obtained from five canines. The effect of mean pump speed and the circulatory perturbations on left and right ventricular pressure volume loops, mean aortic pressure, mean cardiac output, pump assistance ratio, and pump flow pulsatility from both the greyhound experiments and model simulations are demonstrated. Furthermore, the applicability of some of the previously proposed control parameters, that is, pulsatility index (PI), gradient of PI with respect to pump speed, pump differential pressure, and aortic pressure are discussed based on our observations from experimental and simulation results. It was found that previously proposed control strategies were not able to perform well under highly varying circulatory conditions. Among these, control algorithms which rely on the left ventricular filling pressure appear to be the most robust as they emulate the Frank-Starling mechanism of the heart. PMID:22489771

  18. Assessment of Cerebral Hemodynamic Changes in Pediatric Patients with Moyamoya Disease Using Probabilistic Maps on Analysis of Basal/Acetazolamide Stress Brain Perfusion SPECT

    International Nuclear Information System (INIS)

    To evaluate the hemodynamic changes and the predictive factors of the clinical outcome in pediatric patients with moyamoya disease, we analyzed pre/post basal/acetazolamide stress brain perfusion SPECT with automated volume of interest (VOIs) method. Total fifty six (M:F=33:24, age 6.7±3.2 years) pediatric patients with moyamoya disease, who underwent basal/acetazolamide stress brain perfusion SPECT within 6 before and after revascularization surgery (encephalo-duro-arterio-synangiosis (EDAS) with frontal encephalo-galeo-synangiosis (EGS) and EDAS only followed on contralateral hemisphere), and followed-up more than 6 months after post-operative SPECT, were included. A mean follow-up period after post-operative SPECT was 33±21 months. Each patient's SPECT image was spatially normalized to Korean template with the SPM2. For the regional count normalization, the count of pons was used as a reference region. The basal/acetazolamide-stressed cerebral blood flow (CBF), the cerebral vascular reserve index (CVRI), and the extent of area with significantly decreased basal/acetazolamide- stressed rCBF than age-matched normal control were evaluated on both medial frontal, frontal, parietal, occipital lobes, and whole brain in each patient's images. The post-operative clinical outcome was assigned as good, poor according to the presence of transient ischemic attacks and/or fixed neurological deficits by pediatric neurosurgeon. In a paired t-test, basal/acetazolamide-stressed rCBF and the CVRI were significantly improved after revascularization (p<0.05). The significant difference in the pre-operative basal/acetazolamide-stressed rCBF and the CVRI between the hemispheres where EDAS with frontal EGS was performed and their contralateral counterparts where EDAS only was done disappeared after operation (p<0.05). In an independent student t-test, the pre-operative basal rCBF in the medial frontal gyrus, the post-operative CVRI in the frontal lobe and the parietal lobe of the

  19. Effects of chronic dietary nitrate supplementation on the hemodynamic response to dynamic exercise.

    Science.gov (United States)

    Lee, Jae-Seok; Stebbins, Charles L; Jung, Eunji; Nho, Hosung; Kim, Jong-Kyung; Chang, Myoung-Jei; Choi, Hyun-Min

    2015-09-01

    While acute treatment with beetroot juice (BRJ) containing nitrate (NO3 (-)) can lower systolic blood pressure (SBP), afterload, and myocardial O2 demand during submaximal exercise, effects of chronic supplementation with BRJ (containing a relatively low dose of NO3 (-), 400 mg) on cardiac output (CO), SBP, total peripheral resistance (TPR), and the work of the heart in response to dynamic exercise are not known. Thus, in 14 healthy males (22 ± 1 yr), we compared effects of 15 days of both BRJ and nitrate-depleted beetroot juice (NDBRJ) supplementation on plasma concentrations of NOx (NO3 (-)/NO2 (-)), SBP, diastolic blood pressure (DBP), mean arterial pressure (MAP), CO, TPR, and rate pressure product (RPP) at rest and during progressive cycling exercise. Endothelial function was also assessed via flow-mediated dilation (FMD). BRJ supplementation increased plasma NOx from 83.8 ± 13.8 to 167.6 ± 13.2 μM. Compared with NDBRJ, BRJ reduced SBP, DBP, MAP, and TPR at rest and during exercise (P < 0.05). In addition, RPP was decreased during exercise, while CO was increased, but only at rest and the 30% workload (P < 0.05). BRJ enhanced FMD-induced increases in brachial artery diameter (pre: 12.3 ± 1.6%; post: 17.8 ± 1.9%). We conclude that 1) chronic supplementation with BRJ lowers blood pressure and vascular resistance at rest and during exercise and attenuates RPP during exercise and 2) these effects may be due, in part, to enhanced endothelium-induced vasodilation in contracting skeletal muscle. Findings suggest that BRJ can act as a dietary nutraceutical capable of enhancing O2 delivery and reducing work of the heart, such that exercise can be performed at a given workload for a longer period of time before the onset of fatigue. PMID:26084693

  20. Hemodynamic responses of the caudal artery to toxic tall fescue in beef heifers.

    Science.gov (United States)

    Aiken, G E; Kirch, B H; Strickland, J R; Bush, L P; Looper, M L; Schrick, F N

    2007-09-01

    Color Doppler ultrasonography was used to compare blood flow characteristics in the caudal artery of heifers fed diets with endophyte (Neotyphodium coenophialum) infected (E+) or noninfected (E-) tall fescue seed. Eighteen crossbred (Angus x Brangus) heifers were assigned to 6 pens and were fed chopped alfalfa hay for 5 d and chopped alfalfa hay plus a concentrate that contained E-tall fescue seed for 9 d during an adjustment period. An 11-d experimental period followed, with animals in 3 pens fed chopped alfalfa hay plus a concentrate with E+ seed and those in the other 3 pens fed chopped hay plus concentrate with E E- seed. Color Doppler ultrasound measurements (caudal artery area, peak systolic velocity, end diastolic velocity, mean velocity, heart rate, stroke volume, and flow rate) and serum prolactin were monitored during the adjustment (baseline measures) and during the experimental period. Three baseline measures were collected on d 3, 5, and 6 during the adjustment period for comparison to post E+ seed exposure. Statistical analyses compared the proportionate differences between baseline and response at 4, 28, 52, 76, 100, 172, and 268 h from initial feeding of E+ seed. Serum prolactin concentrations on both diets were lower (P 0.10) to the baseline for 172 and 268 h measures. Blood flow in E+ heifers was consistently lower than the baseline from 4 (P 0.10) from baseline measures during the experimental period. Results indicated that onset of toxicosis was within 4 h of cattle exposure to E+ tall fescue and is related to vasoconstriction and reduction in heart rate. PMID:17526671

  1. Angiotensin II type 1 receptors and systemic hemodynamic and renal responses to stress and altered blood volume in conscious rabbits

    Directory of Open Access Journals (Sweden)

    RogerGeorgeEvans

    2011-07-01

    Full Text Available We examined how systemic blockade of type 1 angiotensin (AT1- receptors affects reflex control of the circulation and the kidney. In conscious rabbits, the effects of candesartan on responses of systemic and renal hemodynamics and renal excretory function to acute hypoxia, mild hemorrhage and plasma volume expansion were tested. Candesartan reduced resting mean arterial pressure (MAP, -8 ± 2% without significantly altering cardiac output (CO, increased renal blood flow (RBF, +38 ± 9% and reduced renal vascular resistance (RVR, -32 ± 6%. Glomerular filtration rate (GFR was not significantly altered but sodium excretion (UNa+V increased four-fold. After vehicle treatment, hypoxia (10% inspired O2 for 30 min did not significantly alter MAP or CO, but reduced HR (-17 ± 6%, increased RVR (+33 ± 16% and reduced GFR (-46 ± 16% and UNa+V (-41 ± 17%. Candesartan did not significantly alter these responses. After vehicle treatment, plasma volume expansion increased CO (+35 ± 7%, reduced total peripheral resistance (TPR, -26 ± 5%, increased RBF (+62 ± 23% and reduced RVR (-32 ± 9%, but did not significantly alter MAP or HR. It also increased UNa+V (803 ± 184% yet reduced GFR (-47 ± 9%. Candesartan did not significantly alter these responses. After vehicle treatment, mild hemorrhage did not significantly alter MAP but increased HR (+16 ± 3%, reduced CO (-16 ± 4% and RBF (-18 ± 6%, increased TPR (+18 ± 4% and tended to increase RVR (+18 ± 9%, P = 0.1, but had little effect on GFR or UNa+V. But after candesartan treatment MAP fell during hemorrhage (-19 ± 1%, while neither TPR nor RVR increased, and GFR (-64 ± 18% and UNa+V (-83 ± 10% fell. AT1-receptor activation supports MAP and GFR during hypovolemia. But AT1-receptors appear to play little role in the renal vasoconstriction, hypofiltration and antinatriuresis accompanying hypoxia, or the systemic and renal vasodilatation and natriuresis accompanying plasma volume expansion.

  2. Hemodynamic mechanisms of the attenuated blood pressure response to mental stress after a single bout of maximal dynamic exercise in healthy subjects

    Directory of Open Access Journals (Sweden)

    F.J. Neves

    2012-07-01

    Full Text Available To determine the hemodynamic mechanisms responsible for the attenuated blood pressure response to mental stress after exercise, 26 healthy sedentary individuals (age 29 ± 8 years underwent the Stroop color-word test before and 60 min after a bout of maximal dynamic exercise on a treadmill. A subgroup (N = 11 underwent a time-control experiment without exercise. Blood pressure was continuously and noninvasively recorded by infrared finger photoplethysmography. Stroke volume was derived from pressure signals, and cardiac output and peripheral vascular resistance were calculated. Perceived mental stress scores were comparable between mental stress tests both in the exercise (P = 0.96 and control (P = 0.24 experiments. After exercise, the blood pressure response to mental stress was attenuated (pre: 10 ± 13 vs post: 6 ± 7 mmHg; P 0.05. In conclusion, a single bout of maximal dynamic exercise attenuates the blood pressure response to mental stress in healthy subjects, along with lower stroke volume and cardiac output, denoting an acute modulatory action of exercise on the central hemodynamic response to mental stress.

  3. Slow spontaneous hemodynamic oscillations during sleep measured with near-infrared spectroscopy

    Science.gov (United States)

    Virtanen, Jaakko; Näsi, Tiina; Noponen, Tommi; Toppila, Jussi; Salmi, Tapani; Ilmoniemi, Risto J.

    2011-07-01

    Spontaneous cerebral hemodynamic oscillations below 100 mHz reflect the level of cerebral activity, modulate hemodynamic responses to tasks and stimuli, and may aid in detecting various pathologies of the brain. Near-infrared spectroscopy (NIRS) is ideally suited for both measuring spontaneous hemodynamic oscillations and monitoring sleep, but little research has been performed to combine these two applications. We analyzed 30 all-night NIRS-electroencephalography (EEG) sleep recordings to investigate spontaneous hemodynamic activity relative to sleep stages determined by polysomnography. Signal power of hemodynamic oscillations in the low-frequency (LF, 40-150 mHz) and very-low-frequency (VLF, 3-40 mHz) bands decreased in slow-wave sleep (SWS) compared to light sleep (LS) and rapid-eye-movement (REM) sleep. No statistically significant (p sleep in line with earlier studies with other modalities. These results increase our knowledge of the physiology of sleep, complement EEG data, and demonstrate the applicability of NIRS to studying spontaneous hemodynamic fluctuations during sleep.

  4. Comparison of the efficacy of esmolol and lidocaine in the control of hemodynamic response associated with intubation: A randomized controlled trial

    OpenAIRE

    Tolga Ergönenç; Jalan Şerbetçigil; Uğur Uzun; Ali Dirik; Gülşen Bican

    2013-01-01

    Objectives: The purpose of this randomized study is tocompare the effects of esmolol and lidocaine in the controlof hemodynamic response caused by endotrachealintubation.Methods: In this study, 40 patients with ASA I-II physicalstatus and between the ages of 19 and 76 were includedand randomly divided into two groups. In the Group E (n =20), iv bolus injection of 1.5 mg/kg esmolol, in the GroupL (n = 20), iv bolus injection of 1.5 mg/kg 2% lidocainewere given with iv bolus injection in 30 sec...

  5. Premedication effect of dexmedetomidine and alfentanil on seizure time, recovery duration, and hemodynamic responses in electroconvulsive therapy

    Directory of Open Access Journals (Sweden)

    Esmail Moshiri

    2016-01-01

    Full Text Available Introduction: Electroconvulsive therapy (ECT is an effective treatment for many mental disorders, especially severe and persistent depression, bipolar disorder, and schizophrenia. The aim of this study is to compare the effect of dexmedetomidine and alfentanil on agitation, satisfaction, seizure duration, and patients hemodynamic after ECT. Materials and Methods: In a three phase crossover randomized clinical trial, 75 patients aged between 18 and 50 years and candidate for ECT were enrolled and assigned into three groups (25 patients in each group. All patients, respectively, took premedication of dexmedetomidine, alfentanil, or saline in three consecutive phases. Patients received 0.5 μg/kg dexmedetomidine, 10 μg/kg alfentanil or normal saline intravenously, 10 min before induction. Finally, seizure and recovery duration, satisfaction and agitation score, and hemodynamic parameters were evaluated. Results: There was no significant difference about seizure duration, agitation score, and hemodynamic parameters between groups but recovery duration was significantly lower in the control group than dexmedetomidine (P = 0.016 and alfentanil group (P = 0.0001. Patients′ satisfaction was significantly higher in intervention groups (alfentanil and dexmedetomidine groups (P = 0.0001. Conclusion: Given the equal effects of alfentanil and dexmedetomidine, it seems that choosing one of these two drugs for premedication of patients undergoing ECT is appropriate. Drug choice is influenced by numerous factors such as accessibility of each drug and the dominance of anesthesiologist and psychiatrist.

  6. Diffusion Based Modeling of Human Brain Response to External Stimuli

    CERN Document Server

    Namazi, Hamidreza

    2012-01-01

    Human brain response is the overall ability of the brain in analyzing internal and external stimuli in the form of transferred energy to the mind/brain phase-space and thus, making the proper decisions. During the last decade scientists discovered about this phenomenon and proposed some models based on computational, biological, or neuropsychological methods. Despite some advances in studies related to this area of the brain research there was less effort which have been done on the mathematical modeling of the human brain response to external stimuli. This research is devoted to the modeling of human EEG signal, as an alert state of overall human brain activity monitoring, due to receiving external stimuli, based on fractional diffusion equation. The results of this modeling show very good agreement with the real human EEG signal and thus, this model can be used as a strong representative of the human brain activity.

  7. Support Network Responses to Acquired Brain Injury

    Science.gov (United States)

    Chleboun, Steffany; Hux, Karen

    2011-01-01

    Acquired brain injury (ABI) affects social relationships; however, the ways social and support networks change and evolve as a result of brain injury is not well understood. This study explored ways in which survivors of ABI and members of their support networks perceive relationship changes as recovery extends into the long-term stage. Two…

  8. Functional MRI of food-induced brain responses

    OpenAIRE

    Smeets, P.A.M.

    2006-01-01

    The ultimate goal of this research was to find central biomarkers of satiety, i.e., physiological measures in the brain that relate to subjectively rated appetite, actual food intake, or both. This thesis describes the changes in brain activity in response to food stimuli as measured by functional MRI, with a focus on the hypothalamus. The hypothalamus is a brain area of particular interest because of its central role in the regulation of food intake. Two earlier studies showed that one long ...

  9. Effect of sevoflurane versus propofol-based anesthesia on the hemodynamic response and recovery characteristics in patients undergoing microlaryngeal surgery

    Directory of Open Access Journals (Sweden)

    Neerja Bharti

    2012-01-01

    Full Text Available Background: This randomized study was conducted to compare the hemodynamic changes and emergence characteristics of sevoflurane versus propofol anesthesia for microlaryngeal surgery. Methods: Forty adult patients undergoing microlaryngoscopy were randomly allocated into two groups. In propofol group, anesthesia was induced with 2-3 mg/kg propofol and maintained with propofol infusion 50-200 μg/kg/h. In sevoflurane group induction was carried out with 5-8% sevoflurane and maintained with sevoflurane in nitrous oxide and oxygen. The propofol and sevoflurane concentrations were adjusted to maintain the bispectral index of 40-60. All patients received fentanyl 2 μg/kg before induction and succinylcholine 2 mg/kg to facilitate tracheal intubation. The hemodynamic changes during induction and suspension laryngoscopy were compared. In addition, the emergence time, time to extubation, and recovery were assessed. Results: The changes in heart rate were comparable. The mean arterial pressure was significantly lower after induction and higher at insertion of operating laryngoscope in propofol group as compared to sevoflurane group. More patients in propofol group had episodes of hypotension and hypertension than sevoflurane group. The emergence time, extubation times, and recovery time were similar in both groups. Conclusion: We found that sevoflurane showed advantage over propofol in respect of intraoperative cardiovascular stability without increasing recovery time.

  10. Brain Responses Differ to Faces of Mothers and Fathers

    Science.gov (United States)

    Arsalidou, Marie; Barbeau, Emmanuel J.; Bayless, Sarah J.; Taylor, Margot J.

    2010-01-01

    We encounter many faces each day but relatively few are personally familiar. Once faces are familiar, they evoke semantic and social information known about the person. Neuroimaging studies demonstrate differential brain activity to familiar and non-familiar faces; however, brain responses related to personally familiar faces have been more rarely…

  11. The effects of clonidine premedication and scalp infiltration of lidocaine on hemodynamic responses to laryngoscopy and skull pin head-holder insertion during skull base procedures.

    Science.gov (United States)

    Jellish, W S; Theard, M A; Cheng, M A; Leonetti, J P; Crowder, C M; Tempelhoff, R

    2001-08-01

    This study was designed to determine if oral clonidine or lidocaine, injected into the scalp before head-holder (H-H) insertion, would attenuate the hemodynamic effects associated with intubation and H-H placement. Thirty-four patients undergoing skull base procedures were randomized to four groups. Group 1 received clonidine 5 mcg/kg po before surgery with 10 to 15 ml of 1% lidocaine infiltrated at pin insertion sites; Group 2 received clonidine with saline infiltration; Group 3 received a placebo preoperatively and had lidocaine infiltrated at pin sites; and Group 4 received a placebo with saline infiltrated. All patients had a standard anesthetic titrated to a 10 to 14 Hz EEG endpoint during laryngoscopy and H-H placement. Mean arterial pressure (MAP) was similar between groups during intubation, but heart rate (HR) increased in patients who did not receive clonidine. H-H application increased HR and MAP in Group 4. HR also increased after H-H placement in patients who received oral clonidine, while patients receiving scalp lidocaine or both clonidine and scalp lidocaine had little change in either value. Clonidine attenuated HR increases after laryngoscopy but not after H-H placement. Lidocaine injected at the pin sites reduced HR, and MAP increased after H-H insertion. The combination of oral clonidine and scalp lidocaine blunted hemodynamic responses to both intubation and H-H placement. PMID:17167618

  12. Benevolent sexism alters executive brain responses.

    Science.gov (United States)

    Dardenne, Benoit; Dumont, Muriel; Sarlet, Marie; Phillips, Christophe; Balteau, Evelyne; Degueldre, Christian; Luxen, André; Salmon, Eric; Maquet, Pierre; Collette, Fabienne

    2013-07-10

    Benevolence is widespread in our societies. It is defined as considering a subordinate group nicely but condescendingly, that is, with charity. Deleterious consequences for the target have been reported in the literature. In this experiment, we used functional MRI (fMRI) to identify whether being the target of (sexist) benevolence induces changes in brain activity associated with a working memory task. Participants were confronted by benevolent, hostile, or neutral comments before and while performing a reading span test in an fMRI environment. fMRI data showed that brain regions associated previously with intrusive thought suppression (bilateral, dorsolateral, prefrontal, and anterior cingulate cortex) reacted specifically to benevolent sexism compared with hostile sexism and neutral conditions during the performance of the task. These findings indicate that, despite being subjectively positive, benevolence modifies task-related brain networks by recruiting supplementary areas likely to impede optimal cognitive performance. PMID:23660680

  13. Brain response abnormalities during verbal learning among patients with schizophrenia

    OpenAIRE

    Eyler, Lisa T; Jeste, Dilip V.; Brown, Gregory G.

    2007-01-01

    Patients with schizophrenia often show verbal learning deficits that have been linked to the pathophysiology of the disorder and result in functional impairment. This study examined the biological basis of these deficits by comparing the brain response of patients with schizophrenia (n=17) to that of healthy comparison participants (n=14) during a verbal paired-associates learning task using functional magnetic resonance imaging (fMRI). Brain response during new word learning was examined wit...

  14. Occupational exposure in hemodynamic

    International Nuclear Information System (INIS)

    This paper has an objective to perform a radiometric survey at a hemodynamic service. Besides, it was intended to evaluate the effective dose of health professionals and to provide data which can contribute with minimization of exposures during the realization of hemodynamic procedure. The radiometric survey was realized in the real environment of work simulating the conditions of a hemodynamic study with a ionization chamber

  15. A STUDY ON COMPARISON OF INTRAVENOUS DEXMEDETOMIDINE WITH INTRAVENOUS FENTANYL FOR SUPPRESSION OF HEMODYNAMIC RESPONSES TO LARYNGOSCOPY AND ENDOTRACHEAL INTUBATION DURING GENERAL ANAESTHESIA

    Directory of Open Access Journals (Sweden)

    Nidhi D Patel

    2015-06-01

    Full Text Available Background: Laryngoscopy and intubation is the Gold standard for airway management but this evokes a stress response which is exhibited in the form of changes in heart rate, blood pressure and arrhythmias. This study was prospective, randomized, double blind study to determine whether the fentanyl 2 and micro;g/Kg or dexmedetomidine 1 and micro;g/Kg would decrease the attenuation of hemodynamic response during laryngoscopy and tracheal intubation during general anaesthesia. Methodology: The patients were randomly allocated into two groups. In Group D cases (n=30 received injection Dexmedetomidine 1 and micro;g/kg diluted to 10ml NS IV over 10min using syringe pump prior to intubation and 5ml of NS 5 min. prior to intubation. In Group F cases (n=30 received 2 and micro;g/kg diluted to 5ml NS 5min. prior to intubation and 20ml NS in infusion pump over 10 min., prior to intubation. Results: The age and weight of the cases in both the groups are comparable. It was observed that mean HR increased in both groups D and F immediately after endotracheal intubation. The systolic blood pressure was highly significant in group F as compared to group D during laryngoscopy and intubation, 1, 3, 5 and 10 min after intubation (p<0.000. Ramsay sedation score was and #8805; 4 in all patients in group D and was and #8804; 3 in group F. Dexmedetomidine has higher sedation score but no respiratory depression. Conclusion: We concluded that dexmedetomidine in dose 1 and micro;gm/kg i.v. is more effective in attenuating the hemodynamic pressor responses to laryngoscopy and intubation than Inj. Fentanyl 2 and micro;gm/kg i.v. when given as pre-medicant without significant side effects. [Natl J Med Res 2015; 5(2.000: 127-131

  16. The Teenage Brain: The Stress Response and the Adolescent Brain

    OpenAIRE

    Romeo, Russell D.

    2013-01-01

    Adolescence is a time of many psychosocial and physiological changes. One such change is how an individual responds to stressors. Specifically, adolescence is marked by significant shifts in hypothalamic-pituitary-adrenal (HPA) axis reactivity, resulting in heightened stress-induced hormonal responses. It is presently unclear what mediates these changes in stress reactivity and what impacts they may have on an adolescent individual. However, stress-sensitive limbic and corti...

  17. In-vivo optical imaging and spectroscopy of cerebral hemodynamics

    Science.gov (United States)

    Zhou, Chao

    Functional optical imaging techniques, such as diffuse optical imaging and spectroscopy and laser speckle imaging (LSI), were used in research and clinical settings to measure cerebral hemodynamics. In this thesis, theoretical and experimental developments of the techniques and their in-vivo applications ranging from small animals to adult humans are demonstrated. Near infrared diffuse optical techniques non-invasively measure hemoglobin concentrations, blood oxygen saturation (diffuse reflectance spectroscopy, DRS) and blood flow (diffuse correlation spectroscopy, DCS) in deep tissues, e.g. brain. A noise model was derived for DCS measurements. Cerebral blood flow (CBF) measured with DCS was validated with arterial-spin-labeling MRI. Three-dimensional CBF tomography was obtained during cortical spreading depression from a rat using the optimized diffuse correlation tomographic method. Cerebral hemodynamics in newborn piglets after traumatic brain injury were continuously monitored optically for six hours to demonstrate the feasibility of using diffuse optical techniques as bedside patient monitors. Cerebral autoregulation in piglets and human stroke patients was demonstrated to be non-invasively assessable via the continuous DCS measurement. Significant differences of CBF responses to head-of-bead maneuvers were observed between the peri- and contra-infarct hemispheres in human stroke patients. A significant portion of patient population showed paradoxical CBF responses, indicating the importance of individualized stroke management. The development of a speckle noise model revealed the source of noise for LSI. LSI was then applied to study the acute functional recovery of the rat brain following transient brain ischemia. The spatial and temporal cerebral blood flow responses to functional stimulation were statistically quantified. The area of activation, and the temporal response to stimulation were found significantly altered by the ischemic insult, while the

  18. Hemodynamic changes in rats after radioprotective combination of cystamine administered subcutaneously and 5-methoxytryptamine injected intramuscularly

    International Nuclear Information System (INIS)

    Administration of cystamine (20 mg base/kg s.c.) and 5-methoxytryptamine (10 mg base/kg i.m.) with 12 minutes delay to anesthetized rats induced the depression of whole cardiovascular system, hemoconcentration and great blood flow decrease in the radiosensitive tissues. Distribution of lowered cardiac output preferred the fractions to brain, heart, liver and lungs. Hemodynamic responses to protective combination may participate in its radioprotective action. (orig.)

  19. 5-HTTLPR differentially predicts brain network responses to emotional faces

    DEFF Research Database (Denmark)

    Fisher, Patrick M; Grady, Cheryl L; Madsen, Martin K;

    2015-01-01

    The effects of the 5-HTTLPR polymorphism on neural responses to emotionally salient faces have been studied extensively, focusing on amygdala reactivity and amygdala-prefrontal interactions. Despite compelling evidence that emotional face paradigms engage a distributed network of brain regions...... involved in emotion, cognitive and visual processing, less is known about 5-HTTLPR effects on broader network responses. To address this, we evaluated 5-HTTLPR differences in the whole-brain response to an emotional faces paradigm including neutral, angry and fearful faces using functional magnetic...... to fearful faces was significantly greater in S' carriers compared to LA LA individuals. These findings provide novel evidence for emotion-specific 5-HTTLPR effects on the response of a distributed set of brain regions including areas responsive to emotionally salient stimuli and critical components...

  20. Simultaneous EEG-fMRI in patients with Unverricht-Lundborg disease: event-related desynchronization/synchronization and hemodynamic response analysis.

    Science.gov (United States)

    Visani, Elisa; Minati, Ludovico; Canafoglia, Laura; Gilioli, Isabella; Salvatoni, Lucia; Varotto, Giulia; Fazio, Patrik; Aquino, Domenico; Bruzzone, Maria Grazia; Franceschetti, Silvana; Panzica, Ferruccio

    2010-01-01

    We performed simultaneous acquisition of EEG-fMRI in seven patients with Unverricht-Lundborg disease (ULD) and in six healthy controls using self-paced finger extension as a motor task. The event-related desynchronization/synchronization (ERD/ERS) analysis showed a greater and more diffuse alpha desynchronization in central regions and a strongly reduced post-movement beta-ERS in patients compared with controls, suggesting a significant dysfunction of the mechanisms regulating active movement and movement end. The event-related hemodynamic response obtained from fMRI showed delayed BOLD peak latency in the contralateral primary motor area suggesting a less efficient activity of the neuronal populations driving fine movements, which are specifically impaired in ULD. PMID:20111730

  1. Influence of Age on Brain Edema Formation, Secondary Brain Damage and Inflammatory Response after Brain Trauma in Mice

    Science.gov (United States)

    Timaru-Kast, Ralph; Luh, Clara; Gotthardt, Philipp; Huang, Changsheng; Schäfer, Michael K.; Engelhard, Kristin; Thal, Serge C.

    2012-01-01

    After traumatic brain injury (TBI) elderly patients suffer from higher mortality rate and worse functional outcome compared to young patients. However, experimental TBI research is primarily performed in young animals. Aim of the present study was to clarify whether age affects functional outcome, neuroinflammation and secondary brain damage after brain trauma in mice. Young (2 months) and old (21 months) male C57Bl6N mice were anesthetized and subjected to a controlled cortical impact injury (CCI) on the right parietal cortex. Animals of both ages were randomly assigned to 15 min, 24 h, and 72 h survival. At the end of the observation periods, contusion volume, brain water content, neurologic function, cerebral and systemic inflammation (CD3+ T cell migration, inflammatory cytokine expression in brain and lung, blood differential cell count) were determined. Old animals showed worse neurological function 72 h after CCI and a high mortality rate (19.2%) compared to young (0%). This did not correlate with histopathological damage, as contusion volumes were equal in both age groups. Although a more pronounced brain edema formation was detected in old mice 24 hours after TBI, lack of correlation between brain water content and neurological deficit indicated that brain edema formation is not solely responsible for age-dependent differences in neurological outcome. Brains of old naïve mice were about 8% smaller compared to young naïve brains, suggesting age-related brain atrophy with possible decline in plasticity. Onset of cerebral inflammation started earlier and primarily ipsilateral to damage in old mice, whereas in young mice inflammation was delayed and present in both hemispheres with a characteristic T cell migration pattern. Pulmonary interleukin 1β expression was up-regulated after cerebral injury only in young, not aged mice. The results therefore indicate that old animals are prone to functional deficits and strong ipsilateral cerebral inflammation

  2. Influence of age on brain edema formation, secondary brain damage and inflammatory response after brain trauma in mice.

    Directory of Open Access Journals (Sweden)

    Ralph Timaru-Kast

    Full Text Available After traumatic brain injury (TBI elderly patients suffer from higher mortality rate and worse functional outcome compared to young patients. However, experimental TBI research is primarily performed in young animals. Aim of the present study was to clarify whether age affects functional outcome, neuroinflammation and secondary brain damage after brain trauma in mice. Young (2 months and old (21 months male C57Bl6N mice were anesthetized and subjected to a controlled cortical impact injury (CCI on the right parietal cortex. Animals of both ages were randomly assigned to 15 min, 24 h, and 72 h survival. At the end of the observation periods, contusion volume, brain water content, neurologic function, cerebral and systemic inflammation (CD3+ T cell migration, inflammatory cytokine expression in brain and lung, blood differential cell count were determined. Old animals showed worse neurological function 72 h after CCI and a high mortality rate (19.2% compared to young (0%. This did not correlate with histopathological damage, as contusion volumes were equal in both age groups. Although a more pronounced brain edema formation was detected in old mice 24 hours after TBI, lack of correlation between brain water content and neurological deficit indicated that brain edema formation is not solely responsible for age-dependent differences in neurological outcome. Brains of old naïve mice were about 8% smaller compared to young naïve brains, suggesting age-related brain atrophy with possible decline in plasticity. Onset of cerebral inflammation started earlier and primarily ipsilateral to damage in old mice, whereas in young mice inflammation was delayed and present in both hemispheres with a characteristic T cell migration pattern. Pulmonary interleukin 1β expression was up-regulated after cerebral injury only in young, not aged mice. The results therefore indicate that old animals are prone to functional deficits and strong ipsilateral cerebral

  3. Dexmedetomidine as an adjunct to anesthetic induction to attenuate hemodynamic response to endotracheal intubation in patients undergoing fast-track CABG

    Directory of Open Access Journals (Sweden)

    Menda Ferdi

    2010-01-01

    Full Text Available During induction of general anesthesia hypertension and tachycardia caused by tracheal intubation may lead to cardiac ischemia and arrhythmias. In this prospective, randomized study, dexmedetomidine has been used to attenuate the hemodynamic response to endotracheal intubation with low dose fentanyl and etomidate in patients undergoing myocardial revascularization receiving beta blocker treatment. Thirty patients undergoing myocardial revascularization received in a double blind manner, either a saline placebo or a dexmedetomidine infusion (1 µg/kg before the anesthesia induction. Heart rate (HR and blood pressure (BP were monitored at baseline, after placebo or dexmedetomidine infusion, after induction of general anesthesia, one, three and five minutes after endotracheal intubation. In the dexmedetomidine (DEX group systolic (SAP, diastolic (DAP and mean arterial pressures (MAP were lower at all times in comparison to baseline values; in the placebo (PLA group SAP, DAP and MAP decreased after the induction of general anesthesia and five minutes after the intubation compared to baseline values. This decrease was not significantly different between the groups. After the induction of general anesthesia, the drop in HR was higher in DEX group compared to PLA group. One minute after endotracheal intubation, HR significantly increased in PLA group while, it decreased in the DEX group. The incidence of tachycardia, hypotension and bradycardia was not different between the groups. The incidence of hypertension requiring treatment was significantly greater in the PLA group. It is concluded that dexmedetomidine can safely be used to attenuate the hemodynamic response to endotracheal intubation in patients undergoing myocardial revascularization receiving beta blockers.

  4. Comparison of the efficacy of esmolol and lidocaine in the control of hemodynamic response associated with intubation: A randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Tolga Ergönenç

    2013-03-01

    Full Text Available Objectives: The purpose of this randomized study is tocompare the effects of esmolol and lidocaine in the controlof hemodynamic response caused by endotrachealintubation.Methods: In this study, 40 patients with ASA I-II physicalstatus and between the ages of 19 and 76 were includedand randomly divided into two groups. In the Group E (n =20, iv bolus injection of 1.5 mg/kg esmolol, in the GroupL (n = 20, iv bolus injection of 1.5 mg/kg 2% lidocainewere given with iv bolus injection in 30 seconds. All patientsreceived the same anesthetic technique. Systolicblood pressure (SBP, diastolic blood pressure (DBPand mean blood pressure (MBP and heart rate measurementswere done at specified times and recorded. Recordswere assessed by an anesthesiologist blinded towhich drug is applied.Results: There was no difference between the groupsin demographic data (p>0.05. In both groups, with theimplementation of the study drug, systolic blood pressure,diastolic blood pressure and mean arterial blood pressuredecreased compared to controls, this reduction was lowerin Group E than Group L. In Group L, SBP values of 1.5and 7 minutes were higher than Group E (p <0.05. InGroup L, DBP and MBP values of 1.5 and 3.5 minuteswere higher than Group E (p <0.05.Conclusion: In conclusion, 1.5 mg/kg esmolol or 1.5 mg/kg lidocaine administered prior to induction were not superiorto each other regarding suppression of hemodynamicresponses to intubation. J Clin Exp Invest 2013; 4(1: 20-27Key words: Esmolol, lidocaine, intubation, hemodynamic response

  5. Immune responses at brain barriers and implications for brain development and neurological function in later life

    Directory of Open Access Journals (Sweden)

    Helen B. Stolp

    2013-08-01

    Full Text Available For a long time the brain has been considered an immune-privileged site due to a muted inflammatory response and the presence of protective brain barriers. It is now recognised that neuroinflammation may play an important role in almost all neurological disorders and that the brain barriers may be contributing through either normal immune signalling, or disruption of their basic physiological mechanisms. The distinction between normal function and dysfunction at the barriers is difficult to dissect, partly due to a lack of understanding of normal barrier function and partly because of physiological changes that occur as part of normal development and ageing. Brain barriers consist of a number of interacting structural and physiological elements including tight junctions between adjacent barrier cells and an array of influx and efflux transporters. Despite these protective mechanisms, the capacity for immune-surveillance of the brain is maintained, and there is evidence of inflammatory signalling at the brain barriers that may be an important part of the body’s response to damage or infection. This signalling system appears to change both with normal ageing, and during disease. Changes may affect diapedesis of immune cells and active molecular transfer, or cause rearrangement of the tight junctions and an increase in passive permeability across barrier interfaces. Here we review the many elements that contribute to brain barrier functions and how they respond to inflammation, particularly during development and aging. The implications of inflammation–induced barrier dysfunction for brain development and subsequent neurological function are also discussed.

  6. Food-induced brain responses and eating behaviour

    OpenAIRE

    Smeets, P.A.M.; CHARBONNIER, L.; Meer, van der, D; Laan, van der, Paul Maarten; Spetter, M.S.

    2012-01-01

    The brain governs food intake behaviour by integrating many different internal and external state and trait-related signals. Understanding how the decisions to start and to stop eating are made is crucial to our understanding of (maladaptive patterns of) eating behaviour. Here, we aim to (1) review the current state of the field of 'nutritional neuroscience' with a focus on the interplay between food-induced brain responses and eating behaviour and (2) highlight research needs and techniques ...

  7. Individual classification of ADHD children by right prefrontal hemodynamic responses during a go/no-go task as assessed by fNIRS

    Directory of Open Access Journals (Sweden)

    Yukifumi Monden

    2015-01-01

    Full Text Available While a growing body of neurocognitive research has explored the neural substrates associated with attention deficit hyperactive disorder (ADHD, an objective biomarker for diagnosis has not been established. The advent of functional near-infrared spectroscopy (fNIRS, which is a noninvasive and unrestrictive method of functional neuroimaging, raised the possibility of introducing functional neuroimaging diagnosis in young ADHD children. Previously, our fNIRS-based measurements successfully visualized the hypoactivation pattern in the right prefrontal cortex during a go/no-go task in ADHD children compared with typically developing control children at a group level. The current study aimed to explore a method of individual differentiation between ADHD and typically developing control children using multichannel fNIRS, emphasizing how spatial distribution and amplitude of hemodynamic response are associated with inhibition-related right prefrontal dysfunction. Thirty ADHD and thirty typically developing control children underwent a go/no-go task, and their cortical hemodynamics were assessed using fNIRS. We explored specific regions of interest (ROIs and cut-off amplitudes for cortical activation to distinguish ADHD children from control children. The ROI located on the border of inferior and middle frontal gyri yielded the most accurate discrimination. Furthermore, we adapted well-formed formulae for the constituent channels of the optimized ROI, leading to improved classification accuracy with an area under the curve value of 85% and with 90% sensitivity. Thus, the right prefrontal hypoactivation assessed by fNIRS would serve as a potentially effective biomarker for classifying ADHD children at the individual level.

  8. Hemodynamic Responses of Unfit Healthy Women at a Training Session with Nintendo Wii: A Possible Impact on the General Well-Being

    Science.gov (United States)

    Monteiro-Junior, Renato S; Figueiredo, Luiz F; Conceição, Isabel; Carvalho, Carolina; Lattari, Eduardo; Mura, Gioia; Machado, Sérgio; da Silva, Elirez B

    2014-01-01

    Aims: The purpose of this study was assess the effect of a training session with Nintendo Wii® on the hemodynamic responses of healthy women not involved in regular physical exercise. Method: Twenty-five healthy unfit women aged 28 ± 6 years played for 10 minutes the game Free Run (Wii Fit Plus). The resting heart rate (RHR), systolic and diastolic blood pressures (SBP and DBP), and double (rate-pressure) product (DP) were measured before and after activity. The HR during the activity (exercise heart rate, EHR) was measured every minute. Results: A statistically significant difference was observed between the RHR (75 ± 9 bpm) and the mean EHR (176 ± 15 bpm) (P < 0.001). The EHR remained in the target zone for aerobic exercise until the fifth minute of activity, which coincided with the upper limit of the aerobic zone (80% heart rate reserve (HRR) + RHR) from the sixth to tenth minute. The initial (110 ± 8 mmHg) and final (145 ± 17 mmHg) SBP (P < 0.01) were significantly different, as were the initial (71 ± 8 mmHg) and final (79 ± 9 mmHg) DBP (P < 0.01). A statistically significant difference was observed between the pre- (8.233 ± 1.141 bpm-mmHg) and post-activity (25.590 ± 4.117 bpm-mmHg) DP (P < 0.01). Conclusion: Physical exercise while playing Free Run sufficed to trigger acute hemodynamic changes in healthy women who were not engaged in regular physical exercise. PMID:25614754

  9. Fetal Inflammatory Response and Brain Injury in the Preterm Newborn

    OpenAIRE

    Malaeb, Shadi; Dammann, Olaf

    2009-01-01

    Preterm birth can be caused by intrauterine infection and maternal/fetal inflammatory responses. Maternal inflammation (chorioamnionitis) is often followed by a systemic fetal inflammatory response characterized by elevated levels of pro-inflammatory cytokines in the fetal circulation. The inflammation signal is likely transmitted across the blood-brain barrier, and initiates a neuroinflammatory response. Microglial activation has a central role in this process, and triggers excitotoxic, infl...

  10. The fetal brain sparing response to hypoxia: physiological mechanisms.

    Science.gov (United States)

    Giussani, Dino A

    2016-03-01

    How the fetus withstands an environment of reduced oxygenation during life in the womb has been a vibrant area of research since this field was introduced by Joseph Barcroft, a century ago. Studies spanning five decades have since used the chronically instrumented fetal sheep preparation to investigate the fetal compensatory responses to hypoxia. This defence is contingent on the fetal cardiovascular system, which in late gestation adopts strategies to decrease oxygen consumption and redistribute the cardiac output away from peripheral vascular beds and towards essential circulations, such as those perfusing the brain. The introduction of simultaneous measurement of blood flow in the fetal carotid and femoral circulations by ultrasonic transducers has permitted investigation of the dynamics of the fetal brain sparing response for the first time. Now we know that major components of fetal brain sparing during acute hypoxia are triggered exclusively by a carotid chemoreflex and that they are modified by endocrine agents and the recently discovered vascular oxidant tone. The latter is determined by the interaction between nitric oxide and reactive oxygen species. The fetal brain sparing response matures as the fetus approaches term, in association with the prepartum increase in fetal plasma cortisol, and treatment of the preterm fetus with clinically relevant doses of synthetic steroids mimics this maturation. Despite intense interest into how the fetal brain sparing response may be affected by adverse intrauterine conditions, this area of research has been comparatively scant, but it is likely to take centre stage in the near future. PMID:26496004

  11. Comparison of nifedipine gastrointestinal therapeutic system and atenolol on antianginal efficacies and exercise hemodynamic responses in stable angina pectoris.

    Science.gov (United States)

    Wallace, W A; Wellington, K L; Chess, M A; Liang, C S

    1994-01-01

    A gastrointestinal therapeutic system (GITS) of nifedipine has been developed to provide a once-daily dosing, and predictable, relatively constant plasma concentrations. This study compared the antianginal efficacy of nifedipine GITS with a once-a-day beta-receptor blocker, atenolol. Seventeen patients with documented coronary artery disease and stable stress-induced angina pectoris were studied during a 2-week, single-blind, placebo baseline phase and a 12-week randomized, double-blind, active drug crossover efficacy phase, using the bicycle exercise test and ambulatory electrocardiographic recordings. Patients exercised significantly longer with nifedipine GITS (883 +/- 47 seconds) and atenolol (908 +/- 44 seconds) than with placebo (794 +/- 41 seconds). Nifedipine GITS reduced systolic blood pressure at all stages of exercise compared with placebo but, because heart rate tended to increase more during nifedipine therapy, there was no difference in rate-pressure products between the placebo and nifedipine GITS periods. In contrast, atenolol reduced heart rate, systolic blood pressure and rate-pressure product during exercise compared with placebo. Whereas left ventricular ejection fractions (by radionuclide angiocardiography) increased with exercise, the maximal increase was smaller with atenolol than with placebo and nifedipine. The net increase in left ventricular ejection fraction at the end of exercise was greater with nifedipine than with placebo or atenolol. Ambulatory electrocardiograms showed only a small number of ischemic events. Neither nifedipine GITS nor atenolol reduced the number of ischemic events or total duration of ST-segment deviations significantly. It is concluded that nifedipine GITS is as effective an antianginal agent as atenolol, but the hemodynamic effects of the 2 agents differ.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8279372

  12. Reduced Prefrontal Hemodynamic Response in Pediatric Obsessive-Compulsive Disorder as Measured by Near-Infrared Spectroscopy

    Science.gov (United States)

    Ota, Toyosaku; Iida, Junzo; Sawada, Masayuki; Suehiro, Yuko; Yamamuro, Kazuhiko; Matsuura, Hiroki; Tanaka, Shohei; Kishimoto, Naoko; Negoro, Hideki; Kishimoto, Toshifumi

    2013-01-01

    Recent developments in near-infrared spectroscopy (NIRS) have enabled non-invasive clarification of brain functions in psychiatric disorders. Functional neuroimaging studies of patients with obsessive-compulsive disorder (OCD) have suggested that the frontal cortex and subcortical structures may play a role in the pathophysiology of the disorder.…

  13. Hemodynamic Response to Featural Changes in the Occipital and Inferior Temporal Cortex in Infants: A Preliminary Methodological Exploration

    Science.gov (United States)

    Wilcox, Teresa; Bortfeld, Heather; Woods, Rebecca; Wruck, Eric; Boas, David A.

    2008-01-01

    Over the past 30 years researchers have learned a great deal about the development of object processing in infancy. In contrast, little is understood about the neural mechanisms that underlie this capacity, in large part because there are few techniques available to measure brain functioning in human infants. The present research examined the…

  14. Regional genome transcriptional response of adult mouse brain to hypoxia

    Directory of Open Access Journals (Sweden)

    Lu Aigang

    2011-10-01

    Full Text Available Abstract Background Since normal brain function depends upon continuous oxygen delivery and short periods of hypoxia can precondition the brain against subsequent ischemia, this study examined the effects of brief hypoxia on the whole genome transcriptional response in adult mouse brain. Result Pronounced changes of gene expression occurred after 3 hours of hypoxia (8% O2 and after 1 hour of re-oxygenation in all brain regions. The hypoxia-responsive genes were predominantly up-regulated in hindbrain and predominantly down-regulated in forebrain - possibly to support hindbrain survival functions at the expense of forebrain cognitive functions. The up-regulated genes had a significant role in cell survival and involved both shared and unshared signaling pathways among different brain regions. Up-regulation of transcriptional signaling including hypoxia inducible factor, insulin growth factor (IGF, the vitamin D3 receptor/retinoid X nuclear receptor, and glucocorticoid signaling was common to many brain regions. However, many of the hypoxia-regulated target genes were specific for one or a few brain regions. Cerebellum, for example, had 1241 transcripts regulated by hypoxia only in cerebellum but not in hippocampus; and, 642 (54% had at least one hepatic nuclear receptor 4A (HNF4A binding site and 381 had at least two HNF4A binding sites in their promoters. The data point to HNF4A as a major hypoxia-responsive transcription factor in cerebellum in addition to its known role in regulating erythropoietin transcription. The genes unique to hindbrain may play critical roles in survival during hypoxia. Conclusion Differences of forebrain and hindbrain hypoxia-responsive genes may relate to suppression of forebrain cognitive functions and activation of hindbrain survival functions, which may coordinately mediate the neuroprotection afforded by hypoxia preconditioning.

  15. Brain stem auditory evoked responses in human infants and adults

    Science.gov (United States)

    Hecox, K.; Galambos, R.

    1974-01-01

    Brain stem evoked potentials were recorded by conventional scalp electrodes in infants (3 weeks to 3 years of age) and adults. The latency of one of the major response components (wave V) is shown to be a function both of click intensity and the age of the subject; this latency at a given signal strength shortens postnatally to reach the adult value (about 6 msec) by 12 to 18 months of age. The demonstrated reliability and limited variability of these brain stem electrophysiological responses provide the basis for an optimistic estimate of their usefulness as an objective method for assessing hearing in infants and adults.

  16. Behavioural and brain responses related to Internet search and memory.

    Science.gov (United States)

    Dong, Guangheng; Potenza, Marc N

    2015-10-01

    The ready availability of data via searches on the Internet has changed how many people seek and perhaps store and recall information, although the brain mechanisms underlying these processes are not well understood. This study investigated brain mechanisms underlying Internet-based vs. non-Internet-based searching. The results showed that Internet searching was associated with lower accuracy in recalling information as compared with traditional book searching. During functional magnetic resonance imaging, Internet searching was associated with less regional brain activation in the left ventral stream, the association area of the temporal-parietal-occipital cortices, and the middle frontal cortex. When comparing novel items with remembered trials, Internet-based searching was associated with higher brain activation in the right orbitofrontal cortex and lower brain activation in the right middle temporal gyrus when facing those novel trials. Brain activations in the middle temporal gyrus were inversely correlated with response times, and brain activations in the orbitofrontal cortex were positively correlated with self-reported search impulses. Taken together, the results suggest that, although Internet-based searching may have facilitated the information-acquisition process, this process may have been performed more hastily and be more prone to difficulties in recollection. In addition, people appear less confident in recalling information learned through Internet searching and that recent Internet searching may promote motivation to use the Internet. PMID:26262779

  17. Brain connectomics predict response to treatment in social anxiety disorder.

    Science.gov (United States)

    Whitfield-Gabrieli, S; Ghosh, S S; Nieto-Castanon, A; Saygin, Z; Doehrmann, O; Chai, X J; Reynolds, G O; Hofmann, S G; Pollack, M H; Gabrieli, J D E

    2016-05-01

    We asked whether brain connectomics can predict response to treatment for a neuropsychiatric disorder better than conventional clinical measures. Pre-treatment resting-state brain functional connectivity and diffusion-weighted structural connectivity were measured in 38 patients with social anxiety disorder (SAD) to predict subsequent treatment response to cognitive behavioral therapy (CBT). We used a priori bilateral anatomical amygdala seed-driven resting connectivity and probabilistic tractography of the right inferior longitudinal fasciculus together with a data-driven multivoxel pattern analysis of whole-brain resting-state connectivity before treatment to predict improvement in social anxiety after CBT. Each connectomic measure improved the prediction of individuals' treatment outcomes significantly better than a clinical measure of initial severity, and combining the multimodal connectomics yielded a fivefold improvement in predicting treatment response. Generalization of the findings was supported by leave-one-out cross-validation. After dividing patients into better or worse responders, logistic regression of connectomic predictors and initial severity combined with leave-one-out cross-validation yielded a categorical prediction of clinical improvement with 81% accuracy, 84% sensitivity and 78% specificity. Connectomics of the human brain, measured by widely available imaging methods, may provide brain-based biomarkers (neuromarkers) supporting precision medicine that better guide patients with neuropsychiatric diseases to optimal available treatments, and thus translate basic neuroimaging into medical practice. PMID:26260493

  18. Cooperative dynamics in auditory brain response

    CERN Document Server

    Kwapien, J; Liu, L C; Ioannides, A A

    1998-01-01

    Simultaneous estimates of the activity in the left and right auditory cortex of five normal human subjects were extracted from Multichannel Magnetoencephalography recordings. Left, right and binaural stimulation were used, in separate runs, for each subject. The resulting time-series of left and right auditory cortex activity were analysed using the concept of mutual information. The analysis constitutes an objective method to address the nature of inter-hemispheric correlations in response to auditory stimulations. The results provide a clear evidence for the occurrence of such correlations mediated by a direct information transport, with clear laterality effects: as a rule, the contralateral hemisphere leads by 10-20ms, as can be seen in the average signal. The strength of the inter-hemispheric coupling, which cannot be extracted from the average data, is found to be highly variable from subject to subject, but remarkably stable for each subject.

  19. Blood pressure and renal hemodynamic responses to acute angiotensin II infusion are enhanced in a female mouse model of systemic lupus erythematosus

    OpenAIRE

    Venegas-Pont, Marcia; Mathis, Keisa W.; Iliescu, Radu; Ray, William H.; Glover, Porter H.; Ryan, Michael J.

    2011-01-01

    Inflammation and immune system dysfunction contributes to the development of cardiovascular and renal disease. Systemic lupus erythematosus (SLE) is a chronic autoimmune inflammatory disorder that carries a high risk for both renal and cardiovascular disease. While hemodynamic changes that may contribute to increased cardiovascular risk have been reported in humans and animal models of SLE, renal hemodynamics have not been widely studied. The renin-angiotensin system (RAS) plays a central rol...

  20. Dexmedetomidine versus esmolol to attenuate the hemodynamic response to laryngoscopy and tracheal intubation: A randomized double-blind clinical study

    OpenAIRE

    Reddy, Siddareddigari Velayudha; Balaji, Donthu; Ahmed, Shaik Nawaz

    2014-01-01

    Context: Sympathoadrenal response to laryngoscopy and tracheal intubation manifests as transient, but distinct tachycardia and hypertension. Aims: The objective of this study is to compare the clinical effects of dexmedetomidine with esmolol and control in attenuating the presser response during laryngoscopy. Settings and Design: A randomized, prospective, double-blind, controlled study. Subjects and Methods: We studied consented, 90 adult, American Society of Anesthesiologists physical statu...

  1. The effect of different doses of esmolol on hemodynamic, bispectral index and movement response during orotracheal intubation: prospective, randomized, double-blind study

    Directory of Open Access Journals (Sweden)

    Mensure Yılmaz Çakırgöz

    2014-12-01

    Full Text Available Objective: A prospective, randomized and double-blind study was planned to identify the optimum dose of esmolol infusion to suppress the increase in bispectral index values and the movement and hemodynamic responses to tracheal intubation. Materials and methods: One hundred and twenty patients were randomly allocated to one of three groups in a double-blind fashion. 2.5 mg kg-1 propofol was administered for anesthesia induction. After loss of consciousness, and before administration of 0.6 mg kg-1 rocuronium, a tourniquet was applied to one arm and inflated to 50 mm Hg greater than systolic pressure. The patients were divided into 3 groups; 1 mg kg-1 h-1 esmolol was given as the loading dose and in Group Es50 50 μg kg-1 min-1, in Group Es150 150 μg kg-1 min-1, and in Group Es250 250 μg kg-1 min-1 esmolol infusion was started. Five minutes after the esmolol has been begun, the trachea was intubated; gross movement within the first minute after orotracheal intubation was recorded. Results: Incidence of movement response and the ΔBIS max values were comparable in Group Es250 and Group Es150, but these values were significantly higher in Group Es50 than in the other two groups. In all three groups in the 1st minute after tracheal intubation heart rate and mean arterial pressure were significantly higher compared to values from before intubation (p < 0.05. In the study period there was no significant difference between the groups in terms of heart rate and mean arterial pressure. Conclusion: In clinical practise we believe that after 1 mg kg-1 loading dose, 150 μg kg-1 min-1 iv esmolol dose is sufficient to suppress responses to tracheal intubation without increasing side effects.

  2. Comparison of hemodynamic responses to laryngoscopy and intubation with Truview PCD TM , McGrath ® and Macintosh laryngoscope in patients undergoing coronary artery bypass grafting: A randomized prospective study

    Directory of Open Access Journals (Sweden)

    Deepak K Tempe

    2016-01-01

    Full Text Available Context: We hypothesized that reduced oropharyngolaryngeal stimulation with video laryngoscopes would attenuate hemodynamic response to laryngoscopy and intubation. Aim: Comparison of hemodynamic response to laryngoscopy and intubation with video laryngoscopes and Macintosh (MC laryngoscope. Setting and Design: Superspecialty tertiary care public hospital; prospective, randomized control study. Methods: Sixty adult patients undergoing elective coronary artery bypass grafting (CABG were randomly allocated to three groups of 20 each: MC, McGrath (MG, and Truview (TV. Hemodynamic parameters were serially recorded before and after intubation. Laryngoscopic grade, laryngoscopy, and tracheal intubation time, ST segment changes, and intra-/post-operative complications were also recorded and compared between groups. Statistical Analysis: SPSS version 17 was used, and appropriate tests applied. P < 0.05 was considered significant. Results: Heart rate and diastolic arterial pressure increased at 0 and 1 min of intubation in all the three groups (P < 0.05 while mean arterial pressure increased at 0 min in the MG and TV groups and at 1 min in all three groups (P < 0.05. A significant increase in systolic arterial pressure was only observed in TV group at 1 min (P < 0.05. These hemodynamic parameters returned to baseline by 3 min of intubation in all the groups. The intergroup comparisons of all hemodynamic parameters were not significant at any time of observation. Highest intubation difficulty score was observed with MC (2.16 ± 1.86 as compared with MG (0.55 ± 0.88 and TV (0.42 ± 0.83 groups (P = 0.003 and P = 0.001, respectively. However, duration of laryngoscopy and intubation was significantly less in MC (36.68 ± 16.15 s as compared with MG (75.25 ± 30.94 s and TV (60.47 ± 27.45 s groups (P = 0.000 and 0.003, respectively. Conclusions: Video laryngoscopes did not demonstrate any advantage in terms of hemodynamic response in patients with normal

  3. Submillisecond unmasked subliminal visual stimuli evoke electrical brain responses.

    Science.gov (United States)

    Sperdin, Holger F; Spierer, Lucas; Becker, Robert; Michel, Christoph M; Landis, Theodor

    2015-04-01

    Subliminal perception is strongly associated to the processing of meaningful or emotional information and has mostly been studied using visual masking. In this study, we used high density 256-channel EEG coupled with an liquid crystal display (LCD) tachistoscope to characterize the spatio-temporal dynamics of the brain response to visual checkerboard stimuli (Experiment 1) or blank stimuli (Experiment 2) presented without a mask for 1 ms (visible), 500 µs (partially visible), and 250 µs (subliminal) by applying time-wise, assumption-free nonparametric randomization statistics on the strength and on the topography of high-density scalp-recorded electric field. Stimulus visibility was assessed in a third separate behavioral experiment. Results revealed that unmasked checkerboards presented subliminally for 250 µs evoked weak but detectable visual evoked potential (VEP) responses. When the checkerboards were replaced by blank stimuli, there was no evidence for the presence of an evoked response anymore. Furthermore, the checkerboard VEPs were modulated topographically between 243 and 296 ms post-stimulus onset as a function of stimulus duration, indicative of the engagement of distinct configuration of active brain networks. A distributed electrical source analysis localized this modulation within the right superior parietal lobule near the precuneus. These results show the presence of a brain response to submillisecond unmasked subliminal visual stimuli independently of their emotional saliency or meaningfulness and opens an avenue for new investigations of subliminal stimulation without using visual masking. PMID:25487054

  4. Paradoxical effects of brain death and associated trauma on rat mesenteric microcirculation: an intravital microscopic study

    OpenAIRE

    Rafael Simas; Paulina Sannomiya; José Walber M. C Cruz; Cristiano de Jesus Correia; Fernando Luiz Zanoni; Maurício Kase; Laura Menegat; Isaac Azevedo Silva; Moreira, Luiz Felipe P.

    2012-01-01

    OBJECTIVE: Experimental findings support clinical evidence that brain death impairs the viability of organs for transplantation, triggering hemodynamic, hormonal, and inflammatory responses. However, several of these events could be consequences of brain death–associated trauma. This study investigated microcirculatory alterations and systemic inflammatory markers in brain-dead rats and the influence of the associated trauma. METHOD: Brain death was induced using intracranial balloon inflatio...

  5. ATTENUATION OF HEMODYNAMIC STRESS RESPONSE DURING EMERGENCE FROM GENERAL ANAESTHESIA: A PROSPECTIVE RANDOMIZED CONTROLLED STUDY COMPARING FENTANYL AND DEXMEDETOMIDINE

    Directory of Open Access Journals (Sweden)

    Liyakhath

    2014-11-01

    Full Text Available : BACKGROUND: Tracheal extubation and emergence is associated with significant haemodynamic alterations and is poorly tolerated by patients with co-morbid conditions. We compared the efficacy of fentanyl and dexmedetomidine in mitigating haemodynamic stress response and assessed extubation quality in study groups. MATERIALS AND METHODS: One fifty patients of either sex, ASA grade I & II normotensive patients, aged 18-55 years undergoing elective surgeries under general anaesthesia were randomized into 3 equal groups. Anaesthetic technique was standardized. 10 minutes prior to extubation, patients in Group N, F and D received intravenous bolus infusion of 0.9% normal Saline, Fentanyl 1μg /kg and Dexmedetomidine 1μg /kg respectively over 10 minutes period. Heart Rate (HR, Systolic BP (SBP, Diastolic BP (DBP and Mean Arterial Pressure (MAP were noted at extubation, 2, 4, 6, 8, 10 min and at regular interval thereafter for a period of two hours. Extubation quality was evaluated on 5-point extubation quality scale [ scale 1 = no coughing, 2 = smooth extubation, minimal coughing (1 or 2 times, 3 = moderate coughing (3 or 4 times, 4 = severe coughing (5-10 times and straining, 5 = poor extubation, very uncomfortable (laryngospasm and coughing >10 times]. Ramsay sedation score and Aldrete’s recovery score were recorded. Any adverse events, use of rescue drugs and postoperative analgesics were noted. RESULTS: All the measured haemodynamic parameters were significantly elevated at extubation and at various points of observation in normal saline group than fentanyl and dexmedetomidine group (p=0.000. Tachycardia response was seen in 84% patients in group N, compared to 36% and 8% in group F & D respectively (p=0.000. Statistically significant hypertensive response was noticed in 43(86% patients of group N, 9(18% of group F and 3(6% of group D (p=0.000. Duration of tachycardia and hypertensive response was significantly longer in control group. Three

  6. PARP1 activation/expression modulates regional-specific neuronal and glial responses to seizure in a hemodynamic-independent manner

    OpenAIRE

    Kim, J-E; Kim, Y-J; Kim, J.Y.; Kang, T-C

    2014-01-01

    Poly(ADP-ribose) polymerase-1 (PARP1) plays a regulatory role in apoptosis, necrosis and other cellular processes after injury. Status epilepticus (SE) induces neuronal and astroglial death that show regional-specific patterns in the rat hippocampus and piriform cortex (PC). Thus, we investigated whether PARP1 regulates the differential neuronal/glial responses to pilocarpine (PILO)-induced SE in the distinct brain regions. In the present study, both CA1 and CA3 neurons showed PARP1 hyperacti...

  7. Comparison of Dexmedetomidine and Esmolol for Attenuation of Hemodynamic Responses to Laryngoscopy and Tracheal Intubation in Hypertensive Patients

    OpenAIRE

    Özkan, Ahmet Selim; Bombacı, Elif

    2013-01-01

    Aim: During general anesthesia, control of the airway is often provided with endotracheal intubation, as a result, larynx and trachea are stimulated and plasma concentrations of noradrenaline and adrenaline are increased. This increase in blood pressure and heart rate causing arrhythmias and has a negative impact on myocardial oxygen delivery and consumption. Many drugs used for the prevention response to increased sympathic activity in blood pressure and heart rate. It was aimed to evaluate ...

  8. Regional Brain Responses in Nulliparous Women to Emotional Infant Stimuli

    OpenAIRE

    Montoya, Jessica L.; Nicole Landi; Hedy Kober; Worhunsky, Patrick D.; Rutherford, Helena J. V.; W Einar Mencl; Mayes, Linda C.; POTENZA, MARC N.

    2012-01-01

    Infant cries and facial expressions influence social interactions and elicit caretaking behaviors from adults. Recent neuroimaging studies suggest that neural responses to infant stimuli involve brain regions that process rewards. However, these studies have yet to investigate individual differences in tendencies to engage or withdraw from motivationally relevant stimuli. To investigate this, we used event-related fMRI to scan 17 nulliparous women. Participants were presented with novel infan...

  9. Global genetic variations predict brain response to faces

    DEFF Research Database (Denmark)

    Dickie, Erin W; Tahmasebi, Amir; French, Leon;

    2014-01-01

    Face expressions are a rich source of social signals. Here we estimated the proportion of phenotypic variance in the brain response to facial expressions explained by common genetic variance captured by ∼ 500,000 single nucleotide polymorphisms. Using genomic-relationship-matrix restricted maximu...... of connections with other network nodes, suggesting that the genetic model captures variations across the adolescent brains in co-opting these regions into the face network.......Face expressions are a rich source of social signals. Here we estimated the proportion of phenotypic variance in the brain response to facial expressions explained by common genetic variance captured by ∼ 500,000 single nucleotide polymorphisms. Using genomic-relationship-matrix restricted maximum...... face network, as defined previously. In 9 out of these 25 regions, common genetic variance explained a significant proportion of phenotypic variance (40-50%) in their response to ambiguous facial expressions; this was not the case for angry facial expressions. Across the network, the strength of the...

  10. Common resting brain dynamics indicate a possible mechanism underlying zolpidem response in severe brain injury

    OpenAIRE

    Williams, Shawniqua; Conte, Mary; Goldfine, Andrew; Noirhomme, Quentin; Gosseries, Olivia; Thonnard, Marie; Beattie, Bradley; Hersh, Jennifer; Katz, Douglas; Victor, Jonathan; Laureys, Steven; Schiff, Nicholas

    2013-01-01

    eLife digest Some individuals who experience severe brain damage are left with disorders of consciousness. While they can appear to be awake, these individuals lack awareness of their surroundings and cannot respond to events going on around them. Few treatments are available, but a minority of patients show striking improvements in speech, alertness and movement in response to the sleeping pill zolpidem. Although the idea of a sleeping pill increasing consciousness is paradoxical, it is poss...

  11. EFFECTS OF PREANESTHETIC SINGLE DOSE INTRAVENOUS DEXMEDETOMIDINE VERSUS FENTANYL ON HEMODYNAMIC RESPONSE TO ENDOTRACHEAL INTUBATION-A CLINICAL COMPARATIVE STUDY

    Directory of Open Access Journals (Sweden)

    Chandita

    2015-12-01

    Full Text Available INTRODUCTION Many pharmacological agents have been evaluated in regards to their efficacy of blunting the adverse cardiovascular response to laryngoscopy and tracheal intubation. The aim of this study was to evaluate the efficacy of dexmedetomidine compared to fentanyl in blunting the haemodynamic response to laryngoscopy and intubation. METHOD Sixty patients were randomly allocated into two groups (30 patients in each group. The group D received intravenously 1 µgm/kg dexmedetomidine infusion and group F received 2µgm/kg fentanyl infusion. The study drugs were prepared in an identical looking container and were infused fifteen minutes prior to induction of anaesthesia. The study drugs were infused over a period of ten minutes and all the patients underwent a similar anaesthetics technique. Heart rate (HR and blood pressure (systolic, diastolic and mean blood pressure were noted at baseline, at the end of infusion of the study drugs, after induction of anaesthesia, immediately after laryngoscopy and intubation and at 1, 3, 5, 7 and 10 minutes after laryngoscopy and intubation. RESULTS HR significantly decreased in the group D when compared to group F immediately after study drug infusion and there was statistically significant reduction in heart rate for up to 5 min after intubation in both the groups. Although HR increased after intubation in both the groups, the magnitude was lower in the group D. In both the groups, laryngoscopy and intubation led to an increase in systolic, diastolic and mean arterial pressure; the magnitude was lower in the group D. CONCLUSION Dexmeditomidine (1µ/kg attenuates these untoward responses of laryngoscopy and intubation more effectively than fentanyl (2 µ/kg when administered as bolus dose in the pre-induction period of general anaesthesia.

  12. Sex-Steroid Hormone Manipulation Reduces Brain Response to Reward

    DEFF Research Database (Denmark)

    Macoveanu, Julian; Henningsson, Susanne; Pinborg, Anja;

    2016-01-01

    Mood disorders are twice as frequent in women than in men. Risk mechanisms for major depression include adverse responses to acute changes in sex-steroid hormone levels, eg, postpartum in women. Such adverse responses may involve an altered processing of rewards. Here, we examine how women...... to map regional brain activity related to the magnitude of risk during choice and to monetary reward. The GnRHa intervention caused a net reduction in ovarian sex steroids (estradiol and testosterone) and increased depression symptoms. Compared with placebo, GnRHa reduced amygdala's reactivity to...

  13. Effects of race and sex on blood pressure and hemodynamic stress response as a function of the menstrual cycle.

    Science.gov (United States)

    Ahwal; Mills; Kalshan; Nelesen

    1997-08-01

    OBJECTIVE: To examine the influence of race and sex on responses to cardiovascular stress during two menstrual cycle phases. METHODS: Subjects were exposed to two stressors, a mirror star-tracing task and a speaking task. Blood pressure, heart rate, and impedance cardiography measures of reactivity were recorded. Women were examined both during the follicular and during the luteal phase of their menstrual cycle with men matched for the number of days between testing sessions (approximately 6 weeks). The subjects were 33 black and white women and 37 black and white men who were healthy, normotensive, and not being administered medication. RESULTS: For black women, the reactivity of the diastolic blood pressure (DBP) to the speaking task was less in the luteal phase than it was in the follicular phase, whereas for white women (and men) there was no difference between the two phases (testing sessions) (P rate reactivities in both menstrual phases than did men (P speak, black and white women had greater DBP reactivities than did men; however, their DBP responses were attenuated during the luteal phase compared with the follicular phase (P influence this phenomenon. PMID:10234110

  14. Differential role of tumor necrosis factor receptors in mouse brain inflammatory responses in cryolesion brain injury

    DEFF Research Database (Denmark)

    Quintana, Albert; Giralt, Mercedes; Rojas, Santiago;

    2005-01-01

    Tumor necrosis factor-alpha (TNF-alpha) is one of the mediators dramatically increased after traumatic brain injury that leads to the activation, proliferation, and hypertrophy of mononuclear, phagocytic cells and gliosis. Eventually, TNF-alpha can induce both apoptosis and necrosis via intracell......Tumor necrosis factor-alpha (TNF-alpha) is one of the mediators dramatically increased after traumatic brain injury that leads to the activation, proliferation, and hypertrophy of mononuclear, phagocytic cells and gliosis. Eventually, TNF-alpha can induce both apoptosis and necrosis via...... intracellular signaling. This cytokine exerts its functions via interaction with two receptors: type-1 receptor (TNFR1) and type-2 receptor (TNFR2). In this work, the inflammatory response after a freeze injury (cryolesion) in the cortex was studied in wild-type (WT) animals and in mice lacking TNFR1 (TNFR1 KO...... affected by TNFR1 deficiency. Overall, these results suggest that TNFR1 is involved in the early establishment of the inflammatory response and that its deficiency causes a decreased inflammatory response and tissue damage following brain injury....

  15. Modulation of untruthful responses with noninvasive brain stimulation

    Directory of Open Access Journals (Sweden)

    FelipeFregni

    2013-02-01

    Full Text Available Deceptive abilities have long been studied in relation to personality traits. More recently, studies explored the neural substrates associated with deceptive skills suggesting a critical role of the prefrontal cortex. Here we investigated whether noninvasive brain stimulation over the dorsolateral prefrontal cortex (DLPFC could modulate generation of untruthful responses about subject’s personal life across contexts (i.e., deceiving on guilt-free questions on daily activities; generating previously memorized lies about past experience; and producing spontaneous lies about past experience, as well as across modality responses (verbal and motor responses. Results reveal that real, but not sham, transcranial direct current stimulation (tDCS over the DLPFC can reduce response latency for untruthful over truthful answers across contexts and modality responses. Also, contexts of lies seem to incur a different hemispheric laterality. These findings add up to previous studies demonstrating that it is possible to modulate some processes involved in generation of untruthful answers by applying noninvasive brain stimulation over the DLPFC and extend these findings by showing a differential hemispheric contribution of DLPFCs according to contexts.

  16. Signaling the Unfolded Protein Response in primary brain cancers.

    Science.gov (United States)

    Le Reste, Pierre-Jean; Avril, Tony; Quillien, Véronique; Morandi, Xavier; Chevet, Eric

    2016-07-01

    The Unfolded Protein Response (UPR) is an adaptive cellular program used by eukaryotic cells to cope with protein misfolding stress in the Endoplasmic Reticulum (ER). During tumor development, cancer cells are facing intrinsic (oncogene activation) and extrinsic (limiting nutrient or oxygen supply; exposure to chemotherapies) challenges, with which they must cope to survive. Primary brain tumors are relatively rare but deadly and present a significant challenge in the determination of risk factors in the population. These tumors are inherently difficult to cure because of their protected location in the brain. As such surgery, radiation and chemotherapy options carry potentially lasting patient morbidity and incomplete tumor cure. Some of these tumors, such as glioblastoma, were reported to present features of ER stress and to depend on UPR activation to sustain growth, but to date there is no clear general representation of the ER stress status in primary brain tumors. In this review, we describe the key molecular mechanisms controlling the UPR and their implication in cancers. Then we extensively review the literature reporting the status of ER stress in various primary brain tumors and discuss the potential impact of such observation on patient stratification and on the possibility of developing appropriate targeted therapies using the UPR as therapeutic target. PMID:27016056

  17. Comparison of bolus and continuous infusion of esmolol on hemodynamic response to laryngoscopy, endotracheal intubation and sternotomy in coronary artery bypass graft

    Directory of Open Access Journals (Sweden)

    Esra Mercanooglu Efe

    2014-07-01

    Full Text Available BACKGROUND AND OBJECTIVE: The aim of this randomized, prospective and double blinded study is to investigate effects of different esmolol use on hemodynamic response of laryngoscopy, endotracheal intubation and sternotomy in coronary artery bypass graft surgery. METHODS: After approval of local ethics committee and patients' written informed consent, 45 patients were randomized into three groups equally. In Infusion Group; from 10 min before intubation up to 5th minute after sternotomy, 0.5 mg/kg/min esmolol infusion, in Bolus Group; 2 min before intubation and sternotomy 1.5 mg/kg esmolol IV bolus and in Control Group; %0.9 NaCl was administered. All demographic parameters were recorded. Heart rate and blood pressure were recorded before infusion up to anesthesia induction in every minute, during endotracheal intubation, every minute for 10 minutes after endotracheal intubation and before, during and after sternotomy at first and fifth minutes. RESULTS: While area under curve (AUC (SAP × time was being found more in Group B and C than Group I, AUC (SAP × T int and T st and AUC (SAP × T2 was found more in Group B and C than Group I (p < 0.05. Moreover AUC (HR × T st was found less in Group B than Group C but no significant difference was found between Group B and Group I. CONCLUSION: This study highlights that esmolol infusion is more effective than esmolol bolus administration on controlling systolic arterial pressure during endotracheal intubation and sternotomy in CABG surgery.

  18. Relationship between duration of brain death and hemodynamic (in)stability on progressive dysfunction and increased immunologic activation of donor kidneys

    NARCIS (Netherlands)

    van der Hoeven, JAB; Molema, G; Ter Horst, GJ; Freund, RL; Wiersema, J; van Schilfgaarde, R; Leuvenink, HGD; Ploeg, RJ

    2003-01-01

    Background. Consistent difference in graft survival after renal transplantation has been shown when cadaveric transplants are compared to the living related donor situation, in favor of the latter. Recently, evidence has been put forward that brain death has significant effects on the donor organ qu

  19. Is 'bipolar disorder' the brain's autopoietic response to schizophrenia?

    Science.gov (United States)

    Llewellyn, Sue

    2009-10-01

    Evidence is accumulating that schizophrenia and bipolar disorder are related conditions. This paper proposes a particular form of relatedness. If 'schizophrenia' is a mind/brain 'trapped' between waking and dreaming, in a disordered in-between state, then bipolar 'disorder' could actually be an attempt to restore order. The mind/brain is a self-producing, self-organizing system. Autopoiesis applies to such systems. Neuromodulation accomplishes self-organization in the mind/brain. If schizophrenia is a state in-between waking and dreaming, characterized by aminergic/cholinergic interpenetration and dopaminergic imbalance then bipolar 'disorder' could be a modulatory response. This autopoietic reaction may take the form of either aminergic hyperactivity aimed at producing a purer waking state, (precipitating mania in the waking state), or cholinergic hyperactivity aimed at producing a purer dreaming state, (producing depression in the waking state), or both, resulting in rapid cycling bipolar disorder. Thus bipolar activity may be an autopoietic response aimed at restoring differentiation to the in-between state of schizophrenia. PMID:19589644

  20. Obesity and renal hemodynamics

    NARCIS (Netherlands)

    Bosma, R. J.; Krikken, J. A.; van der Heide, J. J. Homan; de Jong, P. E.; Navis, G. J.

    2006-01-01

    Obesity is a risk factor for renal damage in native kidney disease and in renal transplant recipients. Obesity is associated with several renal risk factors such as hypertension and diabetes that may convey renal risk, but obesity is also associated with an unfavorable renal hemodynamic profile inde

  1. Central and regional hemodynamics in prolonged space flights

    Science.gov (United States)

    Gazenko, O. G.; Shulzhenko, E. B.; Turchaninova, V. F.; Egorov, A. D.

    This paper presents the results of measuring central and regional (head, forearm, calf) hemodynamics at rest and during provocative tests by the method of tetrapolar rheography in the course of Salyut-6-Soyuz and Salyut-7-Soyuz missions. The measurements were carried out during short-term (19 man-flights of 7 days in duration) and long-term (21 man-flights of 65-237 days in duration) manned missions. At rest, stroke volume (SV) and cardiac output (CO) as well as heart rate (HR) decreased insignificantly (in short-term flights) or remained essentially unchanged (in long-term flights). In prolonged flights CO increased significantly in response to exercise tests due to an increase in HR and the lack of changes in SV. After exercise tests SV and CO decreased as compared to the preflight level. During lower body negative pressure (LBNP) tests HR and CO were slightly higher than preflight. Changes in regional hemodynamics included a distinct decrease of pulse blood filling (PBF) of the calf, a reduction of the tone of large vessels of the calf and small vessels of the forearm. Head examination (in the region of the internal carotid artery) showed a decrease of PBF of the left hemisphere (during flight months 2-8) and a distinct decline of the tone of small vessels, mainly, in the right hemisphere. During LBNP tests the tone of pre- and postcapillary vessels of the brain returned to normal while PBF of the right and left hemisphere vessels declined. It has been shown that regional circulation variations depend on the area examined and are induced by a rearrangement of total hemodynamics of the human body in microgravity. This paper reviews the data concerning changes in central and regional circulation of men in space flights of different duration.

  2. Hemodynamic and autonomic nervous system responses to mixed meal ingestion in healthy young and old subjects and dysautonomic patients with postprandial hypotension

    Science.gov (United States)

    Lipsitz, L. A.; Ryan, S. M.; Parker, J. A.; Freeman, R.; Wei, J. Y.; Goldberger, A. L.

    1993-01-01

    BACKGROUND. Although postprandial hypotension is a common cause of falls and syncope in elderly persons and in patients with autonomic insufficiency, the pathophysiology of this disorder remains unknown. METHODS AND RESULTS. We examined the hemodynamic, splanchnic blood pool, plasma norepinephrine (NE), and heart rate (HR) power spectra responses to a standardized 400-kcal mixed meal in 11 healthy young (age, 26 +/- 5 years) and nine healthy elderly (age, 80 +/- 5 years) subjects and 10 dysautonomic patients with symptomatic postprandial hypotension (age, 65 +/- 16 years). Cardiac and splanchnic blood pools were determined noninvasively by radionuclide scans, and forearm vascular resistance was determined using venous occlusion plethysmography. In healthy young and old subjects, splanchnic blood volume increased, but supine blood pressure remained unchanged after the meal. In both groups, HR increased and systemic vascular resistance remained stable. Forearm vascular resistance and cardiac index increased after the meal in elderly subjects, whereas these responses were highly variable and of smaller magnitude in the young. Young subjects demonstrated postprandial increases in low-frequency HR spectral power, representing cardiac sympatho-excitation, but plasma NE remained unchanged. In elderly subjects, plasma NE increased after the meal but without changes in the HR power spectrum. Patients with dysautonomia had a large postprandial decline in blood pressure associated with no change in forearm vascular resistance, a fall in systemic vascular resistance, and reduction in left ventricular end diastolic volume index. HR increased in these patients but without changes in plasma NE or the HR power spectrum. CONCLUSIONS. 1) In healthy elderly subjects, the maintenance of blood pressure homeostasis after food ingestion is associated with an increase in HR, forearm vascular resistance, cardiac index, and plasma NE. In both young and old, systemic vascular resistance is

  3. Hormonal contraceptives, menstrual cycle and brain response to faces

    DEFF Research Database (Denmark)

    Marecková, Klara; Perrin, Jennifer S; Nawaz Khan, Irum;

    2014-01-01

    fusiform face area (FFA) in women taking oral contraceptives (vs freely cycling women) and during mid-cycle (vs menstruation) in both groups. Mean blood oxygenation level-dependent response in both left and right FFA increased as function of the duration of OC use. Next, this relationship between the use......Both behavioral and neuroimaging evidence support a female advantage in the perception of human faces. Here we explored the possibility that this relationship may be partially mediated by female sex hormones by investigating the relationship between the brain's response to faces and the use of oral...... contraceptives, as well as the phase of the menstrual cycle. First, functional magnetic resonance images were acquired in 20 young women [10 freely cycling and 10 taking oral contraception (OC)] during two phases of their cycle: mid-cycle and menstruation. We found stronger neural responses to faces in the right...

  4. Hemodynamic responses and upper airway morbidity following tracheal intubation in patients with hypertension: conventional laryngoscopy versus an intubating laryngeal mask airway

    Directory of Open Access Journals (Sweden)

    Elif Bengi Sener

    2012-01-01

    Full Text Available OBJECTIVES: We compared hemodynamic responses and upper airway morbidity following tracheal intubation via conventional laryngoscopy or intubating laryngeal mask airway in hypertensive patients. METHODS: Forty-two hypertensive patients received a conventional laryngoscopy or were intubated with a intubating laryngeal mask airway. Anesthesia was induced with propofol, fentanyl, and cis-atracurium. Measurements of systolic and diastolic blood pressures, heart rate, rate pressure product, and ST segment changes were made at baseline, preintubation, and every minute for the first 5 min following intubation. The number of intubation attempts, the duration of intubation, and airway complications were recorded. RESULTS: The intubation time was shorter in the conventional laryngoscopy group than in the intubating laryngeal mask airway group (16.33 ± 10.8 vs. 43.04±19.8 s, respectively (p<0.001. The systolic and diastolic blood pressures in the intubating laryngeal mask airway group were higher than those in the conventional laryngoscopy group at 1 and 2 min following intubation (p<0.05. The rate pressure product values (heart rate x systolic blood pressure at 1 and 2 min following intubation in the intubating laryngeal mask airway group (15970.90 ± 3750 and 13936.76 ± 2729, respectively were higher than those in the conventional laryngoscopy group (13237.61 ± 3413 and 11937.52 ± 3160, respectively (p<0.05. There were no differences in ST depression or elevation between the groups. The maximum ST changes compared with baseline values were not significant between the groups (conventional laryngoscopy group: 0.328 mm versus intubating laryngeal mask airway group: 0.357 mm; p = 0.754. The number and type of airway complications were similar between the groups. CONCLUSION: The intense and repeated oropharyngeal and tracheal stimulation resulting from intubating laryngeal mask airway induces greater pressor responses than does stimulation resulting from

  5. Sex-Steroid Hormone Manipulation Reduces Brain Response to Reward.

    Science.gov (United States)

    Macoveanu, Julian; Henningsson, Susanne; Pinborg, Anja; Jensen, Peter; Knudsen, Gitte M; Frokjaer, Vibe G; Siebner, Hartwig R

    2016-03-01

    Mood disorders are twice as frequent in women than in men. Risk mechanisms for major depression include adverse responses to acute changes in sex-steroid hormone levels, eg, postpartum in women. Such adverse responses may involve an altered processing of rewards. Here, we examine how women's vulnerability for mood disorders is linked to sex-steroid dynamics by investigating the effects of a pharmacologically induced fluctuation in ovarian sex steroids on the brain response to monetary rewards. In a double-blinded placebo controlled study, healthy women were randomized to receive either placebo or the gonadotropin-releasing hormone agonist (GnRHa) goserelin, which causes a net decrease in sex-steroid levels. Fifty-eight women performed a gambling task while undergoing functional MRI at baseline, during the mid-follicular phase, and again following the intervention. The gambling task enabled us to map regional brain activity related to the magnitude of risk during choice and to monetary reward. The GnRHa intervention caused a net reduction in ovarian sex steroids (estradiol and testosterone) and increased depression symptoms. Compared with placebo, GnRHa reduced amygdala's reactivity to high monetary rewards. There was a positive association between the individual changes in testosterone and changes in bilateral insula response to monetary rewards. Our data provide evidence for the involvement of sex-steroid hormones in reward processing. A blunted amygdala response to rewarding stimuli following a rapid decline in sex-steroid hormones may reflect a reduced engagement in positive experiences. Abnormal reward processing may constitute a neurobiological mechanism by which sex-steroid fluctuations provoke mood disorders in susceptible women. PMID:26245498

  6. Heart function and hemodynamics

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    930469 The effects of different ventricular pac-ing rates on cardiac hemodynamics and theirclinical significance.WEI Meng(魏盟),et al.Zhongshan Hosp,Shanghai Med Univ,Shanghai,200032.Shanghai Med J 1993;16(3):125—126.Changes of hemodynamics were investigated in26 patients at ventricular pacing rate of 60 to120,and 160 bpm.Effects of increasing ventricu-lar pacing rate on EF which were determined bygated blood pool scintigraphy were also studiedin another 11 patients.It is concluded that:1)inpatients with normal cardiac function as well asmost patients with cardiac insufficiency,the rela-tion of CO with increasing pacing rate can be il-

  7. Hemodynamics in fetal arrhythmia.

    Science.gov (United States)

    Sonesson, Sven-Erik; Acharya, Ganesh

    2016-06-01

    Fetal arrhythmias are among the few conditions that can be managed in utero. However, accurate diagnosis is essential for appropriate management. Ultrasound-based imaging methods can be used to study fetal heart structure and function noninvasively and help to understand fetal cardiovascular pathophysiology, and they remain the mainstay of evaluating fetuses with arrhythmias in clinical settings. Hemodynamic evaluation using Doppler echocardiography allows the elucidation of the electrophysiological mechanism and helps to make an accurate diagnosis. It can also be used as a tool to understand fetal cardiac pathophysiology, for assessing fetal condition and monitoring the effect of antiarrhythmic treatment. This narrative review describes Doppler techniques that are useful for evaluating fetal cardiac rhythms to refine diagnosis and provides an overview of hemodynamic changes observed in different types of fetal arrhythmia. PMID:26660845

  8. Strongly compromised inflammatory response to brain injury in interleukin-6-deficient mice

    DEFF Research Database (Denmark)

    Penkowa, M; Moos, T; Carrasco, J;

    1999-01-01

    response in the brain following disruption of the blood-brain barrier (BBB), we examined the effects of a focal cryo injury to the fronto-parietal cortex in interleukin-6-deficient (IL-6-/-) and normal (IL-6+/+) mice. In IL-6+/+ mice, brain injury resulted in the appearance of brain macrophages and...... brain macrophages and reactive astrocytes was markedly depressed and the number of NSE positive neurons was reduced. Brain damage-induced GM-CSF and MT-I+II expression were also markedly depressed compared to IL-6+/+ mice. In contrast, MT-III immunoreactivity was markedly increased in brain macrophages...

  9. Untangling the brain's neuroinflammatory and neurodegenerative transcriptional responses.

    Science.gov (United States)

    Srinivasan, Karpagam; Friedman, Brad A; Larson, Jessica L; Lauffer, Benjamin E; Goldstein, Leonard D; Appling, Laurie L; Borneo, Jovencio; Poon, Chungkee; Ho, Terence; Cai, Fang; Steiner, Pascal; van der Brug, Marcel P; Modrusan, Zora; Kaminker, Joshua S; Hansen, David V

    2016-01-01

    A common approach to understanding neurodegenerative disease is comparing gene expression in diseased versus healthy tissues. We illustrate that expression profiles derived from whole tissue RNA highly reflect the degenerating tissues' altered cellular composition, not necessarily transcriptional regulation. To accurately understand transcriptional changes that accompany neuropathology, we acutely purify neurons, astrocytes and microglia from single adult mouse brains and analyse their transcriptomes by RNA sequencing. Using peripheral endotoxemia to establish the method, we reveal highly specific transcriptional responses and altered RNA processing in each cell type, with Tnfr1 required for the astrocytic response. Extending the method to an Alzheimer's disease model, we confirm that transcriptomic changes observed in whole tissue are driven primarily by cell type composition, not transcriptional regulation, and identify hundreds of cell type-specific changes undetected in whole tissue RNA. Applying similar methods to additional models and patient tissues will transform our understanding of aberrant gene expression in neurological disease. PMID:27097852

  10. Untangling the brain's neuroinflammatory and neurodegenerative transcriptional responses

    Science.gov (United States)

    Srinivasan, Karpagam; Friedman, Brad A.; Larson, Jessica L.; Lauffer, Benjamin E.; Goldstein, Leonard D.; Appling, Laurie L.; Borneo, Jovencio; Poon, Chungkee; Ho, Terence; Cai, Fang; Steiner, Pascal; van der Brug, Marcel P.; Modrusan, Zora; Kaminker, Joshua S.; Hansen, David V.

    2016-01-01

    A common approach to understanding neurodegenerative disease is comparing gene expression in diseased versus healthy tissues. We illustrate that expression profiles derived from whole tissue RNA highly reflect the degenerating tissues' altered cellular composition, not necessarily transcriptional regulation. To accurately understand transcriptional changes that accompany neuropathology, we acutely purify neurons, astrocytes and microglia from single adult mouse brains and analyse their transcriptomes by RNA sequencing. Using peripheral endotoxemia to establish the method, we reveal highly specific transcriptional responses and altered RNA processing in each cell type, with Tnfr1 required for the astrocytic response. Extending the method to an Alzheimer's disease model, we confirm that transcriptomic changes observed in whole tissue are driven primarily by cell type composition, not transcriptional regulation, and identify hundreds of cell type-specific changes undetected in whole tissue RNA. Applying similar methods to additional models and patient tissues will transform our understanding of aberrant gene expression in neurological disease. PMID:27097852

  11. Studying brain function with near-infrared spectroscopy concurrently with electroencephalography

    Science.gov (United States)

    Tong, Y.; Rooney, E. J.; Bergethon, P. R.; Martin, J. M.; Sassaroli, A.; Ehrenberg, B. L.; Van Toi, Vo; Aggarwal, P.; Ambady, N.; Fantini, S.

    2005-04-01

    Near-infrared spectroscopy (NIRS) has been used for functional brain imaging by employing properly designed source-detector matrices. We demonstrate that by embedding a NIRS source-detector matrix within an electroencephalography (EEG) standard multi-channel cap, we can perform functional brain mapping of hemodynamic response and neuronal response simultaneously. In this study, the P300 endogenous evoked response was generated in human subjects using an auditory odd-ball paradigm while concurrently monitoring the hemodynamic response both spatially and temporally with NIRS. The electrical measurements showed the localization of evoked potential P300, which appeared around 320 ms after the odd-ball stimulus. The NIRS measurements demonstrate a hemodynamic change in the fronto-temporal cortex a few seconds after the appearance of P300.

  12. The shopping brain: math anxiety modulates brain responses to buying decisions.

    Science.gov (United States)

    Jones, William J; Childers, Terry L; Jiang, Yang

    2012-01-01

    Metacognitive theories propose that consumers track fluency feelings when buying, which may have biological underpinnings. We explored this using event-related potential (ERP) measures as twenty high-math anxiety (High MA) and nineteen low-math anxiety (Low MA) consumers made buying decisions for promoted (e.g., 15% discount) and non-promoted products. When evaluating prices, ERP correlates of higher perceptual and conceptual fluency were associated with buys, however only for High MA females under no promotions. In contrast, High MA females and Low MA males demonstrated greater FN400 amplitude, associated with enhanced conceptual processing, to prices of buys relative to non-buys under promotions. Concurrent late positive component (LPC) differences under no promotions suggest discrepant retrieval processes during price evaluations between consumer groups. When making decisions to buy or not, larger (smaller) P3, sensitive to outcome responses in the brain, was associated with buying for High MA females (Low MA females) under promotions, an effect also present for males under no promotions. Thus, P3 indexed decisions to buy differently between anxiety groups, but only for promoted items among females and for no promotions among males. Our findings indicate that perceptual and conceptual processes interact with anxiety and gender to modulate brain responses during consumer choices. PMID:22027087

  13. Noninvasive, in vivo imaging of the mouse brain using photoacoustic microscopy

    OpenAIRE

    Stein, Erich W.; Maslov, Konstantin; Wang, Lihong V.

    2009-01-01

    Noninvasive, high resolution imaging of mouse brain activity is poised to provide clinically translatable insights into human neurological disease progression. Toward noninvasive imaging of brain activity through the hemodynamic response, the dark-field photoacoustic microscopy (PAM) technique was enhanced to image the cortex vasculature of the mouse brain in vivo using endogenous hemoglobin contrast. Specifically, the PAM system was redesigned to efficiently collect photoacoustic waves origi...

  14. Regional brain responses in nulliparous women to emotional infant stimuli.

    Science.gov (United States)

    Montoya, Jessica L; Landi, Nicole; Kober, Hedy; Worhunsky, Patrick D; Rutherford, Helena J V; Mencl, W Einar; Mayes, Linda C; Potenza, Marc N

    2012-01-01

    Infant cries and facial expressions influence social interactions and elicit caretaking behaviors from adults. Recent neuroimaging studies suggest that neural responses to infant stimuli involve brain regions that process rewards. However, these studies have yet to investigate individual differences in tendencies to engage or withdraw from motivationally relevant stimuli. To investigate this, we used event-related fMRI to scan 17 nulliparous women. Participants were presented with novel infant cries of two distress levels (low and high) and unknown infant faces of varying affect (happy, sad, and neutral) in a randomized, counter-balanced order. Brain activation was subsequently correlated with scores on the Behavioral Inhibition System/Behavioral Activation System scale. Infant cries activated bilateral superior and middle temporal gyri (STG and MTG) and precentral and postcentral gyri. Activation was greater in bilateral temporal cortices for low- relative to high-distress cries. Happy relative to neutral faces activated the ventral striatum, caudate, ventromedial prefrontal, and orbitofrontal cortices. Sad versus neutral faces activated the precuneus, cuneus, and posterior cingulate cortex, and behavioral activation drive correlated with occipital cortical activations in this contrast. Behavioral inhibition correlated with activation in the right STG for high- and low-distress cries relative to pink noise. Behavioral drive correlated inversely with putamen, caudate, and thalamic activations for the comparison of high-distress cries to pink noise. Reward-responsiveness correlated with activation in the left precentral gyrus during the perception of low-distress cries relative to pink noise. Our findings indicate that infant cry stimuli elicit activations in areas implicated in auditory processing and social cognition. Happy infant faces may be encoded as rewarding, whereas sad faces activate regions associated with empathic processing. Differences in motivational

  15. Regional brain responses in nulliparous women to emotional infant stimuli.

    Directory of Open Access Journals (Sweden)

    Jessica L Montoya

    Full Text Available Infant cries and facial expressions influence social interactions and elicit caretaking behaviors from adults. Recent neuroimaging studies suggest that neural responses to infant stimuli involve brain regions that process rewards. However, these studies have yet to investigate individual differences in tendencies to engage or withdraw from motivationally relevant stimuli. To investigate this, we used event-related fMRI to scan 17 nulliparous women. Participants were presented with novel infant cries of two distress levels (low and high and unknown infant faces of varying affect (happy, sad, and neutral in a randomized, counter-balanced order. Brain activation was subsequently correlated with scores on the Behavioral Inhibition System/Behavioral Activation System scale. Infant cries activated bilateral superior and middle temporal gyri (STG and MTG and precentral and postcentral gyri. Activation was greater in bilateral temporal cortices for low- relative to high-distress cries. Happy relative to neutral faces activated the ventral striatum, caudate, ventromedial prefrontal, and orbitofrontal cortices. Sad versus neutral faces activated the precuneus, cuneus, and posterior cingulate cortex, and behavioral activation drive correlated with occipital cortical activations in this contrast. Behavioral inhibition correlated with activation in the right STG for high- and low-distress cries relative to pink noise. Behavioral drive correlated inversely with putamen, caudate, and thalamic activations for the comparison of high-distress cries to pink noise. Reward-responsiveness correlated with activation in the left precentral gyrus during the perception of low-distress cries relative to pink noise. Our findings indicate that infant cry stimuli elicit activations in areas implicated in auditory processing and social cognition. Happy infant faces may be encoded as rewarding, whereas sad faces activate regions associated with empathic processing. Differences

  16. Promoting motor function by exercising the brain.

    Science.gov (United States)

    Perrey, Stephane

    2013-01-01

    Exercise represents a behavioral intervention that enhances brain health and motor function. The increase in cerebral blood volume in response to physical activity may be responsible for improving brain function. Among the various neuroimaging techniques used to monitor brain hemodynamic response during exercise, functional near-infrared spectroscopy could facilitate the measurement of task-related cortical responses noninvasively and is relatively robust with regard to the subjects' motion. Although the components of optimal exercise interventions have not been determined, evidence from animal and human studies suggests that aerobic exercise with sufficiently high intensity has neuroprotective properties and promotes motor function. This review provides an insight into the effect of physical activity (based on endurance and resistance exercises) on brain function for producing movement. Since most progress in the study of brain function has come from patients with neurological disorders (e.g., stroke and Parkinson's patients), this review presents some findings emphasizing training paradigms for restoring motor function. PMID:24961309

  17. Effects of Emotional Stimuli on Cardiovascular Responses in Patients with Essential Hypertension Based on Brain/Behavioral Systems

    OpenAIRE

    Mohammadreza Taban Sadeghi; Hossein Namdar; Shahram Vahedi; Naser Aslanabadi; Davoud Ezzati; Babak Sadeghi

    2013-01-01

    Introduction: Effects of emotional stimuli on hemodynamics in patients with essential hypertension based on brain/behavioral systems have not been studied broadly. Methods: Eighty five essential hypertensive male patients who had completed Carver-White BIS/BAS scale were enrolled to the study. Later, 25 BIS and 25 BAS patients were selected and their blood pressure and heart rate were recorded prior to stimuli induction. Participants were then exposed to stressor pictures. After that, 15 m...

  18. Differential chemokine responses in the murine brain following lyssavirus infection.

    Science.gov (United States)

    Hicks, D J; Núñez, A; Banyard, A C; Williams, A; Ortiz-Pelaez, A; Fooks, A R; Johnson, N

    2013-11-01

    The hallmark of lyssavirus infection is lethal encephalomyelitis. Previous studies have reported distinct lyssavirus isolate-related differences in severity of cellular recruitment into the encephalon in a murine model of infection following peripheral inoculation with rabies virus (RABV) and European bat lyssavirus (EBLV)-1 and -2. In order to understand the role of chemokines in this process, comparative studies of the chemokine pattern, distribution and production in response to infection with these lyssaviruses were undertaken. Expression of CCL2, CCL5 and CXCL10 was observed throughout the murine brain with a distinct caudal bias in distribution, similar to both inflammatory changes and virus antigen distribution. CCL2 immunolabelling was localized to neuronal and astroglial populations. CCL5 immunolabelling was only detected in the astroglia, while CXCL10 labelling, although present in the astroglia, was more prominent in neurons. Isolate-dependent differences in the amount of chemokine immunolabelling in specific brain regions and chemokine production by neurons in vitro were observed, with a greater expression of CCL5 in vivo and CXCL10 production in vitro after EBLV infection. Additionally, strong positive associations between chemokine immunolabelling and perivascular cuffing and, to a lesser extent, virus antigen score were also observed. These differences in chemokine expression may explain the variation in severity of encephalitic changes observed in animals infected with different lyssavirus isolates. PMID:23746482

  19. Brain response to traumatic brain injury in wild-type and interleukin-6 knockout mice: a microarray analysis

    DEFF Research Database (Denmark)

    Poulsen, Christian Bjørn; Penkowa, Milena; Borup, Rehannah; Nielsen, Finn Cilius; Cáceres, Mario; Quintana, Albert; Molinero, Amalia; Carrasco, Javier; Giralt, Mercedes; Hidalgo, Juan

    2005-01-01

    Traumatic injury to the brain is one of the leading causes of injury-related death or disability. Brain response to injury is orchestrated by cytokines, such as interleukin (IL)-6, but the full repertoire of responses involved is not well known. We here report the results obtained with microarrays...... processes involved in the initial tissue injury and later regeneration of the parenchyma. IL-6 deficiency showed a dramatic effect in the expression of many genes, especially in the 1 day post-lesion timing, which presumably underlies the poor capacity of IL-6 knockout mice to cope with brain damage. The...... results highlight the importance of IL-6 controlling the response of the brain to injury as well as the suitability of microarrays for identifying specific targets worthy of further study....

  20. Common resting brain dynamics indicate a possible mechanism underlying zolpidem response in severe brain injury

    Science.gov (United States)

    Williams, Shawniqua T; Conte, Mary M; Goldfine, Andrew M; Noirhomme, Quentin; Gosseries, Olivia; Thonnard, Marie; Beattie, Bradley; Hersh, Jennifer; Katz, Douglas I; Victor, Jonathan D; Laureys, Steven; Schiff, Nicholas D

    2013-01-01

    Zolpidem produces paradoxical recovery of speech, cognitive and motor functions in select subjects with severe brain injury but underlying mechanisms remain unknown. In three diverse patients with known zolpidem responses we identify a distinctive pattern of EEG dynamics that suggests a mechanistic model. In the absence of zolpidem, all subjects show a strong low frequency oscillatory peak ∼6–10 Hz in the EEG power spectrum most prominent over frontocentral regions and with high coherence (∼0.7–0.8) within and between hemispheres. Zolpidem administration sharply reduces EEG power and coherence at these low frequencies. The ∼6–10 Hz activity is proposed to arise from intrinsic membrane properties of pyramidal neurons that are passively entrained across the cortex by locally-generated spontaneous activity. Activation by zolpidem is proposed to arise from a combination of initial direct drug effects on cortical, striatal, and thalamic populations and further activation of underactive brain regions induced by restoration of cognitively-mediated behaviors. DOI: http://dx.doi.org/10.7554/eLife.01157.001 PMID:24252875

  1. Brain

    Science.gov (United States)

    ... will return after updating. Resources Archived Modules Updates Brain Cerebrum The cerebrum is the part of the ... the outside of the brain and spinal cord. Brain Stem The brain stem is the part of ...

  2. Immunologic, hemodynamic, and adrenal incompetence in cirrhosis

    DEFF Research Database (Denmark)

    Risør, Louise Madeleine; Bendtsen, Flemming; Møller, Søren

    2015-01-01

    Acute kidney injury (AKI) is one of the most severe complications of cirrhosis and is associated with significant morbidity and mortality. Liver fibrosis and liver insufficiency, portal hypertension, systemic vasodilation, and a subsequent hyperdynamic circulation undermine the renal and cardiac...... function, making cirrhotic patients more susceptible to hemodynamic incidents. In addition, the immune system is impaired in cirrhosis, leading to an exaggerated production of vasoactive mediators, and the adrenal cortisol response is insufficient, which causes further impairment of the vascular tonus...... dysfunction, but is not responsive to volume expansion. Recent research indicates that development of hepatic nephropathy represents a continuous spectrum of functional and structural dysfunction and may be precipitated by the inherent immunologic, adrenal, and hemodynamic incompetence in cirrhosis. New...

  3. The Effects of Clonidine Premedication and Scalp Infiltration of Lidocaine on Hemodynamic Responses to Laryngoscopy and Skull Pin Head-Holder Insertion During Skull Base Procedures

    OpenAIRE

    Jellish, W Scott; Theard, M. Angele; Cheng, Mary Ann; Leonetti, John P.; Crowder, C. Michael; Tempelhoff, Rene

    2001-01-01

    This study was designed to determine if oral clonidine or lidocaine, injected into the scalp before head-holder (H-H) insertion, would attenuate the hemodynamic effects associated with intubation and H-H placement. Thirty-four patients undergoing skull base procedures were randomized to four groups. Group 1 received clonidine 5 mcg/kg po before surgery with 10 to 15 ml of 1% lidocaine infiltrated at pin insertion sites; Group 2 received clonidine with saline infiltration; Group 3 received a p...

  4. Hemodynamic Traveling Waves in Human Visual Cortex

    OpenAIRE

    Kevin M Aquino; Schira, Mark M.; P A Robinson; Drysdale, Peter M.; Michael Breakspear

    2012-01-01

    Functional MRI (fMRI) experiments rely on precise characterization of the blood oxygen level dependent (BOLD) signal. As the spatial resolution of fMRI reaches the sub-millimeter range, the need for quantitative modelling of spatiotemporal properties of this hemodynamic signal has become pressing. Here, we find that a detailed physiologically-based model of spatiotemporal BOLD responses predicts traveling waves with velocities and spatial ranges in empirically observable ranges. Two measurabl...

  5. Volume specific response criteria for brain metastases following salvage stereotactic radiosurgery and associated predictors of response

    International Nuclear Information System (INIS)

    Background. We aimed to derive three-dimensional volume-based (V3D) response criteria that approximate those based on Response Evaluation Criteria in Solid Tumours (RECIST) in patients with brain metastases (BM) treated with salvage stereotactic radiosurgery (SRS). Material and methods. Seventy patients with 178 BM were treated with SRS. Each BM was characterised at baseline and at each follow-up MRI according to its widest diameter and V3D using ITK-SNAP image segmentation software. Results. The median tumour diameter was 1.2 cm (range, 0.2-4.5 cm) and V3D was 0.73 cm3 (range, 0.01-22.7 cm3). The V3D percent changes that best matched RECIST response criteria were: an increase of ≥71.5% for progressive disease, a ≥58.5% decrease for partial response and a 3.0 cm (p =0.006) and a V3D >6.0 cm3 (p =0.043) predicted for local failure, and a baseline cumulative V3D of >3.0 cm3 (p =0.02) was adversely prognostic for survival. Conclusions. We define 3D volume specific criteria to base response upon for brain metastases treated with salvage SRS. Tumours with a V3D of greater than 6 cm3 are at a higher risk of local failure

  6. Acute effects of ingesting Java Fit™ energy extreme functional coffee on resting energy expenditure and hemodynamic responses in male and female coffee drinkers

    Directory of Open Access Journals (Sweden)

    Willoughby Darryn S

    2007-10-01

    Full Text Available Abstract Background The purpose of this study was to examine the effects of a functional coffee beverage containing additional caffeine, green tea extracts, niacin and garcinia cambogia to regular coffee to determine the effects on resting energy expenditure (REE and hemodynamic variables. Methods Subjects included five male (26 ± 2.1 y, 97.16 ± 10.05 kg, 183.89 ± 6.60 cm and five female (28.8 ± 5.3 y, 142.2 ± 12.6 lbs regular coffee drinkers. Subjects fasted for 10 hours and were assessed for 1 hour prior (PRE and 3 hours following 1.5 cups of coffee ingestion [JavaFit™ Energy Extreme (JF ~400 mg total caffeine; Folgers (F ~200 mg total caffeine] in a double-blind, crossover design. REE, resting heart rate (RHR, and systolic (SBP and diastolic (DBP blood pressure was assessed at PRE and 1, 2, and 3-hours post coffee ingestion. Data were analyzed by three-factor repeated measures ANOVA (p Results JF trial resulted in a significant main effect for REE (p 2 (p Conclusion Results from this study suggest that JavaFit™ Energy Extreme coffee is more effective than Folgers regular caffeinated coffee at increasing REE in regular coffee drinkers for up to 3 hours following ingestion without any adverse hemodynamic effects.

  7. Detection and Characterization of Single-Trial fMRI BOLD Responses : Paradigm Free Mapping

    NARCIS (Netherlands)

    Gaudes, Cesar Caballero; Petridou, Natalia; Dryden, Ian L.; Bai, Li; Francis, Susan T.; Gowland, Penny A.

    2011-01-01

    This work presents a novel method of mapping the brain's response to single stimuli in space and time without prior knowledge of the paradigm timing: paradigm free mapping (PFM). This method is based on deconvolution of the hemodynamic response from the voxel time series assuming a linear response a

  8. Cerebral hemodynamics in migraine

    DEFF Research Database (Denmark)

    Hachinski, V C; Olesen, Jes; Norris, J W;

    1977-01-01

    Clinical and angiographic findings in migraine are briefly reviewed in relation to cerebral hemodynamic changes shown by regional cerebral blood flow (rCBF) studies. Three cases of migraine studied by the intracarotid xenon 133 method during attacks are reported. In classic migraine, with typical...... prodromal symptoms, a decrease in cerebral blood flow has been demonstrated during the aura. Occasionally, this flow decrease persists during the headache phase. In common migraine, where such prodromata are not seen, a flow decrease has not been demonstrated. During the headache phase of both types of...... migraine, rCBF has usually been found to be normal or in the high range of normal values. The high values may represent postischemic hyperemia, but are probably more frequently secondary to arousal caused by pain. Thus, during the headache phase rCBF may be subnormal, normal or high. These findings do not...

  9. Brain development and predation: plastic responses depend on evolutionary history

    OpenAIRE

    Gonda, Abigél; Välimäki, Kaisa; Herczeg, Gábor; Merilä, Juha

    2011-01-01

    Although the brain is known to be a very plastic organ, the effects of common ecological interactions like predation or competition on brain development have remained largely unexplored. We reared nine-spined sticklebacks (Pungitius pungitius) from two coastal marine (predation-adapted) and two isolated pond (competition-adapted) populations in a factorial experiment, manipulating perceived predatory risk and food supply to see (i) if the treatments affected brain development and (ii) if ther...

  10. Brain response to affective pictures in the chimpanzee

    OpenAIRE

    Satoshi Hirata; Goh Matsuda; Ari Ueno; Hirokata Fukushima; Koki Fuwa; Keiko Sugama; Kiyo Kusunoki; Masaki Tomonaga; Kazuo Hiraki; Toshikazu Hasegawa

    2013-01-01

    Advancement of non-invasive brain imaging techniques has allowed us to examine details of neural activities involved in affective processing in humans; however, no comparative data are available for chimpanzees, the closest living relatives of humans. In the present study, we measured event-related brain potentials in a fully awake adult chimpanzee as she looked at affective and neutral pictures. The results revealed a differential brain potential appearing 210 ms after presentation of an aff...

  11. FLUID AND HEMODYNAMIC MANAGEMENT IN SEVERE DENGUE.

    Science.gov (United States)

    Wongsa, Adisorn

    2015-01-01

    In the critical phase of dengue fever, the leakage of intravascular fluid into interstitial space and 3rd space can cause hemoconcentration and severe complications such as dengue shock syndrome (DSS), and it can lead to multiple organ failure, followed by death. Close monitoring, early detection and prompt management are the keys in successful treatment. In a hemodynamically unstable patient, crystalloid is the fluid of choice in initial management. However, if they are not responsive despite adequate resuscitation, a careful search for others causes is mandatory and fluids should be switched from crystalloid to colloid. If the leakage leads to restriction of the use of fluids (pulmonary edema), the addition of a vasopressor such as norepinephrine needs to be considered. After stabilizing the hemodynamics and clinical improvement, the physician has to know when to reduce and discontinue the fluid to avoid congestion and others complications. PMID:26506738

  12. Active microwave computed brain tomography: the response to a challenge.

    Science.gov (United States)

    Almirall, H; Broquetas, A; Jofre, L

    1991-02-01

    The potential application of active microwave techniques to brain imaging is studied by numerical simulations and experimentally using a recently developed cylindrical microwave scanner. The potential advantages and limitations of this method in static and dynamic brain imaging are presented and compared with other imaging techniques. PMID:2062119

  13. A Response to the Legitimacy of Brain Death in Islam.

    Science.gov (United States)

    Rady, Mohamed Y; Verheijde, Joseph L

    2016-08-01

    Brain death is a novel construct of death for the procurement of transplantable organs. Many authoritative Islamic organizations and governments have endorsed brain death as true death for organ donation. Many commentators have reiterated the misconception that the Quranic text does not define death. We respond by clarifying: (1) the Quran does define death as biologic disintegration and clearly distinguishes it from the dying process, (2) brain death belongs scientifically within the spectrum of neurologic disorders of consciousness and should not be confused with death, and (3) religious and legal discord about brain death has grown in jurisdictions worldwide. We urge for public transparency and truthfulness about brain death and the accommodation and respect of religious objection to the determination of death by neurologic criteria. PMID:27010462

  14. A novel approach to calibrate the Hemodynamic Model using functional Magnetic Resonance Imaging (fMRI) measurements

    KAUST Repository

    Khoram, Nafiseh

    2016-01-21

    Background The calibration of the hemodynamic model that describes changes in blood flow and blood oxygenation during brain activation is a crucial step for successfully monitoring and possibly predicting brain activity. This in turn has the potential to provide diagnosis and treatment of brain diseases in early stages. New Method We propose an efficient numerical procedure for calibrating the hemodynamic model using some fMRI measurements. The proposed solution methodology is a regularized iterative method equipped with a Kalman filtering-type procedure. The Newton component of the proposed method addresses the nonlinear aspect of the problem. The regularization feature is used to ensure the stability of the algorithm. The Kalman filter procedure is incorporated here to address the noise in the data. Results Numerical results obtained with synthetic data as well as with real fMRI measurements are presented to illustrate the accuracy, robustness to the noise, and the cost-effectiveness of the proposed method. Comparison with Existing Method(s) We present numerical results that clearly demonstrate that the proposed method outperforms the Cubature Kalman Filter (CKF), one of the most prominent existing numerical methods. Conclusion We have designed an iterative numerical technique, called the TNM-CKF algorithm, for calibrating the mathematical model that describes the single-event related brain response when fMRI measurements are given. The method appears to be highly accurate and effective in reconstructing the BOLD signal even when the measurements are tainted with high noise level (as high as 30%).

  15. Study on brain hemodynamics function according to data of rheoencephalography during multimodality treatment of oncologic patients with the use of general controlled artificial hyperthermia with hyperglycemia or with large insulin doses

    International Nuclear Information System (INIS)

    For the first time the effect of single and multiple treatments of artificial hyperthermia (AHT) with hyperglycemia (HG) or with large insulin doses on cerebral circulation of oncologic patients is studied. Cerebral hemodynamics was studied by rheoencephalography. The conclusion is made about the unidirectional AHT effect regardless of the bacrground used. 5 refs.; 4 tabs

  16. Correlation of hemodynamic and fluorescence signals under resting state conditions in mice's barrel field cortex.

    Science.gov (United States)

    Bélanger, Samuel; Oliveira Ferreira de Souza, Bruno; Casanova, Christian; Lesage, Frédéric

    2016-03-11

    Both neurons and astrocytes are known to affect local vascular response in the brain following neuronal activity. In order to differentiate the contributions of each cell type to the hemodynamic response during stimulation and resting state, intrinsic optical signal (IOI) was recorded synchronized with fluorescence imaging of calcium concentration sensitive dye Oregon Green BAPTA-1 AM. By changing the stimulation parameters (frequency and duration), it was possible to individually promote neuronal and glial responses and to compare them to levels of oxy (HbO), deoxy (HbR) and total (HbT) hemoglobin concentrations. Finally, resting state recordings were done to investigate the possible correlation between hemoglobin fluctuation and calcium transients, based on different frequency bands associated either with neuronal or glial activity. PMID:26850574

  17. Deep Brain Stimulation Response in Pathologically Confirmed Cases of Multiple System Atrophy

    OpenAIRE

    Ullman, Michael; Vedam-Mai, Vinata; Resnick, Andrew S.; Yachnis, Anthony T.; McFarland, Nikolaus R.; Merritt, Stacy; Zeilman, Pamela; Foote, Kelly D; Okun, Michael S.

    2011-01-01

    Deep brain stimulation is a treatment for select cases of medication refractory movement disorders including Parkinson’s disease. Deep brain stimulation has not been recommended for treatment in multiple system atrophy patients. However, the paucity of literature documenting the effects of deep brain stimulation in multiple system atrophy patients and the revelation of a levodopa-responsive subtype of multiple system atrophy suggests further investigation is necessary.

  18. On the characterization of single-event related brain activity from functional Magnetic Resonance Imaging (fMRI) measurements

    KAUST Repository

    Khoram, Nafiseh

    2014-08-01

    We propose an efficient numerical technique for calibrating the mathematical model that describes the singleevent related brain response when fMRI measurements are given. This method employs a regularized Newton technique in conjunction with a Kalman filtering procedure. We have applied this method to estimate the biophysiological parameters of the Balloon model that describes the hemodynamic brain responses. Illustrative results obtained with both synthetic and real fMRI measurements are presented. © 2014 IEEE.

  19. Measuring cerebral hemodynamics with a modified magnetoencephalography system

    International Nuclear Information System (INIS)

    Magnetoencephalography (MEG) systems are designed to noninvasively measure magnetic fields produced by neural electrical currents. This project examines the possibility of measuring hemodynamics with an MEG system that has been modified with dc electromagnets to measure magnetic susceptibility while maintaining the capability of measuring neural dynamics. A forward model is presented that simulates the interaction of an applied magnetic field with changes in magnetic susceptibility in the brain associated with hemodynamics. Model predictions are compared with an experiment where deionized water was pumped into an inverted flask under the MEG sensor array of superconducting quantum interference device (SQUID) gradiometers (R2 = 0.98, p < 0.001). The forward model was used to simulate the SQUID readouts from hemodynamics in the scalp and brain induced by performing the Valsalva maneuver. Experimental human subject recordings (N = 10) were made from the prefrontal region during Valsalva using concurrent measurement with the modified MEG system and near-infrared spectroscopy (NIRS). The NIRS deoxyhemoglobin signal was found to correlate significantly with the SQUID readouts (R2 = 0.84, p < 0.01). SQUID noise was found to increase with the applied field, which will need to be mitigated in future work. These results demonstrate the potential and technical challenges of measuring cerebral hemodynamics with a modified MEG system. (paper)

  20. The human brain response to dental pain relief.

    Science.gov (United States)

    Meier, M L; Widmayer, S; Abazi, J; Brügger, M; Lukic, N; Lüchinger, R; Ettlin, D A

    2015-05-01

    Local anesthesia has made dental treatment more comfortable since 1884, but little is known about associated brain mechanisms. Functional magnetic resonance imaging is a modern neuroimaging tool widely used for investigating human brain activity related to sensory perceptions, including pain. Most brain regions that respond to experimental noxious stimuli have recently been found to react not only to nociception alone, but also to visual, auditory, and other stimuli. Thus, presumed functional attributions have come under scrutiny regarding selective pain processing in the brain. Evidently, innovative approaches are warranted to identify cerebral regions that are nociceptive specific. In this study, we aimed at circumventing known methodological confounders by applying a novel paradigm in 14 volunteers: rather than varying the intensity and thus the salience of painful stimuli, we applied repetitive noxious dental stimuli at constant intensity to the left mandibular canine. During the functional magnetic resonance imaging paradigm, we suppressed the nociceptive barrage by a mental nerve block. Brain activity before and after injection of 4% articaine was compared intraindividually on a group level. Dental pain extinction was observed to correspond to activity reduction in a discrete region of the left posterior insular cortex. These results confirm previous reports demonstrating that direct electrical stimulation of this brain region-but not of others-evokes bodily pain sensations. Hence, our investigation adds further evidence to the notion that the posterior insula plays a unique role in nociceptive processing. PMID:25691071

  1. A Bayesian model of category-specific emotional brain responses.

    Science.gov (United States)

    Wager, Tor D; Kang, Jian; Johnson, Timothy D; Nichols, Thomas E; Satpute, Ajay B; Barrett, Lisa Feldman

    2015-04-01

    Understanding emotion is critical for a science of healthy and disordered brain function, but the neurophysiological basis of emotional experience is still poorly understood. We analyzed human brain activity patterns from 148 studies of emotion categories (2159 total participants) using a novel hierarchical Bayesian model. The model allowed us to classify which of five categories--fear, anger, disgust, sadness, or happiness--is engaged by a study with 66% accuracy (43-86% across categories). Analyses of the activity patterns encoded in the model revealed that each emotion category is associated with unique, prototypical patterns of activity across multiple brain systems including the cortex, thalamus, amygdala, and other structures. The results indicate that emotion categories are not contained within any one region or system, but are represented as configurations across multiple brain networks. The model provides a precise summary of the prototypical patterns for each emotion category, and demonstrates that a sufficient characterization of emotion categories relies on (a) differential patterns of involvement in neocortical systems that differ between humans and other species, and (b) distinctive patterns of cortical-subcortical interactions. Thus, these findings are incompatible with several contemporary theories of emotion, including those that emphasize emotion-dedicated brain systems and those that propose emotion is localized primarily in subcortical activity. They are consistent with componential and constructionist views, which propose that emotions are differentiated by a combination of perceptual, mnemonic, prospective, and motivational elements. Such brain-based models of emotion provide a foundation for new translational and clinical approaches. PMID:25853490

  2. Improved Detection of Time Windows of Brain Responses in Fmri Using Modified Temporal Clustering Analysis

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    @@ Temporal clustering analysis (TCA) has been proposed recently as a method to detect time windows of brain responses in functional MRI (fMRI) studies when the timing and location of the activation are completely unknown. Modifications to the TCA technique are introduced in this report to further improve the sensitivity in detecting brain activation.

  3. Swimming exercise changes hemodynamic responses evoked by blockade of excitatory amino receptors in the rostral ventrolateral medulla in spontaneously hypertensive rats.

    Science.gov (United States)

    Ogihara, Cristiana A; Schoorlemmer, Gerhardus H M; Lazari, Maria de Fátima M; Giannocco, Gisele; Lopes, Oswaldo U; Colombari, Eduardo; Sato, Monica A

    2014-01-01

    Exercise training reduces sympathetic activity in hypertensive humans and rats. We hypothesized that the swimming exercise would change the neurotransmission in the rostral ventrolateral medulla (RVLM), a key region involved in sympathetic outflow, and hemodynamic control in spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats. Bilateral injections of kynurenic acid (KYN) were carried out in the RVLM in sedentary- (S-) or exercised- (E-) SHR and WKY rats submitted to swimming for 6 weeks. Rats were α-chloralose anesthetized and artificially ventilated, with Doppler flow probes around the lower abdominal aorta and superior mesenteric artery. Injections into the RVLM were made before and after i.v. L-NAME (nitric oxide synthase, NOS, inhibitor). Injections of KYN into the RVLM elicited a major vasodilation in the hindlimb more than in the mesenteric artery in E-SHR compared to S-SHR, but similar decrease in arterial pressure was observed in both groups. Injections of KYN into the RVLM after i.v. L-NAME attenuated the hindlimb vasodilation evoked by KYN and increased the mesenteric vasodilation in E-SHR. Swimming exercise can enhance the hindlimb vasodilation mediated by peripheral NO release, reducing the activation of neurons with EAA receptors in the RVLM in SHR. PMID:24696852

  4. Swimming Exercise Changes Hemodynamic Responses Evoked by Blockade of Excitatory Amino Receptors in the Rostral Ventrolateral Medulla in Spontaneously Hypertensive Rats

    Directory of Open Access Journals (Sweden)

    Cristiana A. Ogihara

    2014-01-01

    Full Text Available Exercise training reduces sympathetic activity in hypertensive humans and rats. We hypothesized that the swimming exercise would change the neurotransmission in the rostral ventrolateral medulla (RVLM, a key region involved in sympathetic outflow, and hemodynamic control in spontaneously hypertensive rats (SHR and Wistar-Kyoto (WKY rats. Bilateral injections of kynurenic acid (KYN were carried out in the RVLM in sedentary- (S- or exercised- (E- SHR and WKY rats submitted to swimming for 6  weeks. Rats were α-chloralose anesthetized and artificially ventilated, with Doppler flow probes around the lower abdominal aorta and superior mesenteric artery. Injections into the RVLM were made before and after i.v. L-NAME (nitric oxide synthase, NOS, inhibitor. Injections of KYN into the RVLM elicited a major vasodilation in the hindlimb more than in the mesenteric artery in E-SHR compared to S-SHR, but similar decrease in arterial pressure was observed in both groups. Injections of KYN into the RVLM after i.v. L-NAME attenuated the hindlimb vasodilation evoked by KYN and increased the mesenteric vasodilation in E-SHR. Swimming exercise can enhance the hindlimb vasodilation mediated by peripheral NO release, reducing the activation of neurons with EAA receptors in the RVLM in SHR.

  5. Altered Brain Response to Drinking Glucose and Fructose in Obese Adolescents.

    Science.gov (United States)

    Jastreboff, Ania M; Sinha, Rajita; Arora, Jagriti; Giannini, Cosimo; Kubat, Jessica; Malik, Saima; Van Name, Michelle A; Santoro, Nicola; Savoye, Mary; Duran, Elvira J; Pierpont, Bridget; Cline, Gary; Constable, R Todd; Sherwin, Robert S; Caprio, Sonia

    2016-07-01

    Increased sugar-sweetened beverage consumption has been linked to higher rates of obesity. Using functional MRI, we assessed brain perfusion responses to drinking two commonly consumed monosaccharides, glucose and fructose, in obese and lean adolescents. Marked differences were observed. In response to drinking glucose, obese adolescents exhibited decreased brain perfusion in brain regions involved in executive function (prefrontal cortex [PFC]) and increased perfusion in homeostatic appetite regions of the brain (hypothalamus). Conversely, in response to drinking glucose, lean adolescents demonstrated increased PFC brain perfusion and no change in perfusion in the hypothalamus. In addition, obese adolescents demonstrated attenuated suppression of serum acyl-ghrelin and increased circulating insulin level after glucose ingestion; furthermore, the change in acyl-ghrelin and insulin levels after both glucose and fructose ingestion was associated with increased hypothalamic, thalamic, and hippocampal blood flow in obese relative to lean adolescents. Additionally, in all subjects there was greater perfusion in the ventral striatum with fructose relative to glucose ingestion. Finally, reduced connectivity between executive, homeostatic, and hedonic brain regions was observed in obese adolescents. These data demonstrate that obese adolescents have impaired prefrontal executive control responses to drinking glucose and fructose, while their homeostatic and hedonic responses appear to be heightened. Thus, obesity-related brain adaptations to glucose and fructose consumption in obese adolescents may contribute to excessive consumption of glucose and fructose, thereby promoting further weight gain. PMID:27207544

  6. Brain response to affective pictures in the chimpanzee.

    Science.gov (United States)

    Hirata, Satoshi; Matsuda, Goh; Ueno, Ari; Fukushima, Hirokata; Fuwa, Koki; Sugama, Keiko; Kusunoki, Kiyo; Tomonaga, Masaki; Hiraki, Kazuo; Hasegawa, Toshikazu

    2013-01-01

    Advancement of non-invasive brain imaging techniques has allowed us to examine details of neural activities involved in affective processing in humans; however, no comparative data are available for chimpanzees, the closest living relatives of humans. In the present study, we measured event-related brain potentials in a fully awake adult chimpanzee as she looked at affective and neutral pictures. The results revealed a differential brain potential appearing 210 ms after presentation of an affective picture, a pattern similar to that in humans. This suggests that at least a part of the affective process is similar between humans and chimpanzees. The results have implications for the evolutionary foundations of emotional phenomena, such as emotional contagion and empathy. PMID:23439389

  7. Language and the newborn brain: Does prenatal language experience shape the neonate neural response to speech?

    OpenAIRE

    LillianMay; KristaByers-Heinlein; JuditGervain

    2011-01-01

    Previous research has shown that by the time of birth, the neonate brain responds specially to the native language when compared to acoustically similar non-language stimuli. In the current study, we use Near Infrared Spectroscopy to ask how prenatal language experience might shape the brain response to language in newborn infants. To do so, we examine the neural response of neonates when listening to familiar versus unfamiliar language, as well as to non-linguistic backwards language. T...

  8. Effects of unexpected chords and of performer's expression on brain responses and electrodermal activity

    OpenAIRE

    Koelsch, S.; Kilches, S.; Steinbeis, N.; Schelinski, S.

    2008-01-01

    BACKGROUND: There is lack of neuroscientific studies investigating music processing with naturalistic stimuli, and brain responses to real music are, thus, largely unknown. METHODOLOGY/PRINCIPAL FINDINGS: This study investigates event-related brain potentials (ERPs), skin conductance responses (SCRs) and heart rate (HR) elicited by unexpected chords of piano sonatas as they were originally arranged by composers, and as they were played by professional pianists. From the musical excerpts pl...

  9. Local Modulation of Human Brain Responses by Circadian Rhythmicity and Sleep Debt

    OpenAIRE

    Muto, V.; Jaspar, M; Meyer, C.; Kussé, C; Chellappa, SL; Degueldre, C.; Balteau, E.; Shaffii-Le Bourdiec, A; Luxen, A; Middleton, B; Archer, SN; Phillips, C.; Collette, F.; Vandewalle, G; Dijk, D

    2016-01-01

    Human performance results from an interaction between circadian rhythmicity and homeostatic sleep pressure. Whether and how this interaction is represented at the regional brain level is not established. We quantified changes in brain responses to a sustained-attention task during 13 functional magnetic resonance imaging (fMRI) sessions scheduled across the circadian cycle during 42h of wakefulness and following recovery sleep, in 33 healthy participants. Cortical responses showed significant...

  10. The synthetic NCAM-derived peptide, FGL, modulates the transcriptional response to traumatic brain injury

    DEFF Research Database (Denmark)

    Pedersen, Martin Volmer; Helweg-Larsen, Rehannah Borup; Nielsen, Finn Cilius;

    2008-01-01

    Cerebral responses to traumatic brain injury (TBI) include up- and downregulation of a vast number of proteins involved in endogenous inflammatory responses and defense mechanisms developing postinjury. The present study analyzed the global gene expression profile in response to cryo-induced TBI by...

  11. Evaluation of intra ocular pressure and hemodynamic change following intubation with Maccoy, Macintosh and Video laryngoscope

    OpenAIRE

    Hamid Khosro Zamiri; Mehrdad Noroozi; Siavash Moradi; Mohammad Shabani; Ali Sharifi; Mohammad Ali Haghbin

    2013-01-01

    Background & Objective: The induction of anesthesia, laryngoscopy and endotracheal intubation can be associated with adverse hemodynamic response and increased intraocular pressure. The aim of this study was to evaluate intraocular pressure and hemodynamic changes after laryngoscopy and endotracheal intubation with three methods of laryngoscopy (Macintosh, Maccoy and Video laryngoscope).Materials & Methods: One hundred and eighty patients with American Society of Anesthesiology (ASA) classifi...

  12. Fractional Diffusion Based Modelling and Prediction of Human Brain Response to External Stimuli

    Directory of Open Access Journals (Sweden)

    Hamidreza Namazi

    2015-01-01

    Full Text Available Human brain response is the result of the overall ability of the brain in analyzing different internal and external stimuli and thus making the proper decisions. During the last decades scientists have discovered more about this phenomenon and proposed some models based on computational, biological, or neuropsychological methods. Despite some advances in studies related to this area of the brain research, there were fewer efforts which have been done on the mathematical modeling of the human brain response to external stimuli. This research is devoted to the modeling and prediction of the human EEG signal, as an alert state of overall human brain activity monitoring, upon receiving external stimuli, based on fractional diffusion equations. The results of this modeling show very good agreement with the real human EEG signal and thus this model can be used for many types of applications such as prediction of seizure onset in patient with epilepsy.

  13. Evolving concepts of hemodynamic monitoring for critically ill patients

    Directory of Open Access Journals (Sweden)

    Olfa Hamzaoui

    2015-01-01

    Full Text Available The last decades have been characterized by a continuous evolution of hemodynamic monitoring techniques from intermittent toward continuous and real-time measurements and from an invasive towards a less invasive approach. The latter approach uses ultrasounds and pulse contour analysis techniques that have been developed over the last 15 years. During the same period, the concept of prediction of fluid responsiveness has also been developed and dynamic indices such as pulse pressure variation, stroke volume variation, and the real-time response of cardiac output to passive leg raising or to end-expiration occlusion, can be easily obtained and displayed with the minimally invasive techniques. In this article, we review the main hemodynamic monitoring devices currently available with their respective advantages and drawbacks. We also present the current viewpoint on how to choose a hemodynamic monitoring device in the most severely ill patients and especially in patients with circulatory shock.

  14. Blood flow responses to mild-intensity exercise in ectopic vs. orthotopic prostate tumors; dependence upon host tissue hemodynamics and vascular reactivity.

    Science.gov (United States)

    Garcia, Emmanuel; Becker, Veronika G C; McCullough, Danielle J; Stabley, John N; Gittemeier, Elizabeth M; Opoku-Acheampong, Alexander B; Sieman, Dietmar W; Behnke, Bradley J

    2016-07-01

    Given the critical role of tumor O2 delivery in patient prognosis and the rise in preclinical exercise oncology studies, we investigated tumor and host tissue blood flow at rest and during exercise as well as vascular reactivity using a rat prostate cancer model grown in two transplantation sites. In male COP/CrCrl rats, blood flow (via radiolabeled microspheres) to prostate tumors [R3327-MatLyLu cells injected in the left flank (ectopic) or ventral prostate (orthotopic)] and host tissue was measured at rest and during a bout of mild-intensity exercise. α-Adrenergic vasoconstriction to norepinephrine (NE: 10(-9) to 10(-4) M) was determined in arterioles perforating the tumors and host tissue. To determine host tissue exercise hyperemia in healthy tissue, a sham-operated group was included. Blood flow was lower at rest and during exercise in ectopic tumors and host tissue (subcutaneous adipose) vs. the orthotopic tumor and host tissue (prostate). During exercise, blood flow to the ectopic tumor significantly decreased by 25 ± 5% (SE), whereas flow to the orthotopic tumor increased by 181 ± 30%. Maximal vasoconstriction to NE was not different between arterioles from either tumor location. However, there was a significantly higher peak vasoconstriction to NE in subcutaneous adipose arterioles (92 ± 7%) vs. prostate arterioles (55 ± 7%). Establishment of the tumor did not alter host tissue blood flow from either location at rest or during exercise. These data demonstrate that blood flow in tumors is dependent on host tissue hemodynamics and that the location of the tumor may critically affect how exercise impacts the tumor microenvironment and treatment outcomes. PMID:27125846

  15. Glial response to 17β-estradiol in neonatal rats with excitotoxic brain injury.

    Science.gov (United States)

    Pansiot, Julien; Pham, Hoa; Dalous, Jeremie; Chevenne, Didier; Colella, Marina; Schwendimann, Leslie; Fafouri, Assia; Mairesse, Jérôme; Moretti, Raffaella; Schang, Anne-Laure; Charriaut-Marlangue, Christiane; Gressens, Pierre; Baud, Olivier

    2016-08-01

    White-matter injury is the most common cause of the adverse neurodevelopmental outcomes observed in preterm infants. Only few options exist to prevent perinatal brain injury associated to preterm delivery. 17β-estradiol (E2) is the predominant estrogen in circulation and has been shown to be neuroprotective in vitro and in vivo. However, while E2 has been found to modulate inflammation in adult models of brain damage, how estrogens influence glial cells response in the developing brain needs further investigations. Using a model of ibotenate-induced brain injury, we have refined the effects of E2 in the developing brain. E2 provides significant neuroprotection both in the cortical plate and the white matter in neonatal rats subjected to excitotoxic insult mimicking white matter and cortical damages frequently observed in very preterm infants. E2 promotes significant changes in microglial phenotypes balance in response to brain injury and the acceleration of oligodendrocyte maturation. Maturational effects of E2 on myelination process were observed both in vivo and in vitro. Altogether, these data demonstrate that response of glial cells to E2 could be responsible for its neuroprotective properties in neonatal excitotoxic brain injury. PMID:27222132

  16. A Response: All "Thinking" Paths Lead to the Brain.

    Science.gov (United States)

    Hart, Leslie A.

    1986-01-01

    Assails schools for rushing into the thinking skills approach without examining advances in cognitive science, artificial intelligence, neuropsychology, and other brain-related disciplines. Blames the classroom situation itself for forcing teachers into counterproductive, direct teaching methods that don't work. Asserts the need for…

  17. Magnetic and electrical responses of the human brain to texture-defined form and to textons.

    Science.gov (United States)

    Regan, D; He, P

    1995-09-01

    1. We searched for a neurophysical correlate of preattentive texture discrimination by recording magnetic and electric evoked responses from the human brain during the first few hundred milliseconds following the presentation of texture-defined (TD) checkerboard form. The only two textons that changed when the TD checkerboard appeared or disappeared were the local orientation and line termination textons. (Textons are conspicuous local features within a texture pattern). 2. Our evidence that the magnetic response to TD form cannot be explained in terms of responses to the two associated textons is as follows: 1) by dissociating the two responses we showed that the magnetic response to TD form is almost entirely independent of the magnetic response to the local orientation texton; 2) a further distinction between the two responses is that their distributions over the head are different; and 3) the magnetic response to TD form differs from the magnetic response to the line termination texton in both distribution over the head and waveform. We conclude that this evidence identifies the existence of a brain response correlate of preattentive texture discrimination. 3. We also recorded brain responses to luminance-defined (LD) checkerboard form. Our grounds for concluding that magnetic brain responses to the onset of checkerboard form are generated by different and independent neural systems for TD and LD form are as follows: 1) magnetic responses to the onset of TD form and LD form had different distributions over the skull, had different waveforms, and depended differently on check size; and 2) the waveform of the response to superimposed TD and LD checks closely approximated the linear sum of responses to TD checks and LD checks alone. 4. One possible explanation for the observed differences between the magnetic and electric evoked responses is that responses to both onset and offset of TD form predominantly involve neurons aligned parallel to the skull, whereas that

  18. Thrombospondin 2-null mice display an altered brain foreign body response to polyvinyl alcohol sponge implants

    Energy Technology Data Exchange (ETDEWEB)

    Tian Weiming; Kyriakides, Themis R, E-mail: themis.kyriakides@yale.ed [Vascular Biology and Therapeutics Program, Departments of Pathology and Biomedical Engineering, Yale University, New Haven, CT 06519 (United States)

    2009-02-15

    Thrombospondin (TSP)-2 is a matricellular protein that participates in the processes of tissue repair and the foreign body response. In addition, TSP2 has been shown to influence synaptogenesis and recovery of the brain following stroke. In the present study we investigated the response following the implantation of polyvinyl alcohol (PVA) sponges in the brain. PVA sponges were implanted into the brain cortex of wild type and TSP2-null mice for a period of 4 and 8 weeks and the response was analyzed by histochemistry and quantitative immunohistochemistry. TSP2 expression was detected in the interstices of the sponge and co-localized with the extracellular matrix and astrocytes. PVA sponge invasion in TSP2-null mice was characterized by dense deposition of extracellular matrix and increased invasion of reactive astrocytes and macrophages/microglia. Furthermore, the angiogenic response was elevated and the detection of mouse serum albumin (MSA) in the brain cortex indicated excessive vessel leakage, suggesting that TSP2 plays a role in the repair/maintenance of the blood brain barrier. Finally, immunostaining demonstrated an increase in the levels of matrix metalloproteinase (MMP)-2 and MMP-9. Taken together, our observations support a role for TSP2 as critical determinant of the brain response to biomaterials.

  19. MicroRNA responses to focal cerebral ischemia in male and female mouse brain

    Directory of Open Access Journals (Sweden)

    Theresa Ann Lusardi

    2014-02-01

    Full Text Available Stroke occurs with greater frequency in men than in women across diverse ethnic backgrounds and nationalities. Work from our lab and others have revealed a sex-specific sensitivity to cerebral ischemia whereby males exhibit a larger extent of brain damage resulting from an ischemic event compared to females. Previous studies revealed that microRNA (miRNA expression is regulated by cerebral ischemia in males; however, no studies to date have examined the effect of ischemia on miRNA responses in females. Thus, we examined miRNA responses in male and female brain in response to cerebral ischemia using miRNA arrays. These studies revealed that in male and female brains, ischemia leads to both a universal miRNA response as well as a sexually distinct response to challenge. Target prediction analysis of the miRNAs increased in male or female ischemic brain reveal sex-specific differences in gene targets and protein pathways. These data support that the mechanisms underlying sexually dimorphic responses to cerebral ischemia includes distinct changes in miRNAs in male and female brain, in addition to a miRNA signature response to ischemia that is common to both.

  20. Pedophilic brain potential responses to adult erotic stimuli.

    Science.gov (United States)

    Knott, Verner; Impey, Danielle; Fisher, Derek; Delpero, Emily; Fedoroff, Paul

    2016-02-01

    Cognitive mechanisms associated with the relative lack of sexual interest in adults by pedophiles are poorly understood and may benefit from investigations examining how the brain processes adult erotic stimuli. The current study used event-related brain potentials (ERP) to investigate the time course of the explicit processing of erotic, emotional, and neutral pictures in 22 pedophilic patients and 22 healthy controls. Consistent with previous studies, early latency anterior ERP components were highly selective for erotic pictures. Although the ERPs elicited by emotional stimuli were similar in patients and controls, an early frontal positive (P2) component starting as early as 185 ms was significantly attenuated and slow to onset in pedophilia, and correlated with a clinical measure of cognitive distortions. Failure of rapid attentional capture by erotic stimuli suggests a relative reduction in early processing in pedophilic patients which may be associated with relatively diminished sexual interest in adults. PMID:26683083

  1. Nonlinear extension of a hemodynamic linear model for coherent hemodynamics spectroscopy.

    Science.gov (United States)

    Sassaroli, Angelo; Kainerstorfer, Jana M; Fantini, Sergio

    2016-01-21

    In this work, we are proposing an extension of a recent hemodynamic model (Fantini, 2014a), which was developed within the framework of a novel approach to the study of tissue hemodynamics, named coherent hemodynamics spectroscopy (CHS). The previous hemodynamic model, from a signal processing viewpoint, treats the tissue microvasculature as a linear time-invariant system, and considers changes of blood volume, capillary blood flow velocity and the rate of oxygen diffusion as inputs, and the changes of oxy-, deoxy-, and total hemoglobin concentrations (measured in near infrared spectroscopy) as outputs. The model has been used also as a forward solver in an inversion procedure to retrieve quantitative parameters that assess physiological and biological processes such as microcirculation, cerebral autoregulation, tissue metabolic rate of oxygen, and oxygen extraction fraction. Within the assumption of "small" capillary blood flow velocity oscillations the model showed that the capillary and venous compartments "respond" to this input as low pass filters, characterized by two distinct impulse response functions. In this work, we do not make the assumption of "small" perturbations of capillary blood flow velocity by solving without approximations the partial differential equation that governs the spatio-temporal behavior of hemoglobin saturation in capillary and venous blood. Preliminary comparison between the linear time-invariant model and the extended model (here identified as nonlinear model) are shown for the relevant parameters measured in CHS as a function of the oscillation frequency (CHS spectra). We have found that for capillary blood flow velocity oscillations with amplitudes up to 10% of the baseline value (which reflect typical scenarios in CHS), the discrepancies between CHS spectra obtained with the linear and nonlinear models are negligible. For larger oscillations (~50%) the linear and nonlinear models yield CHS spectra with differences within typical

  2. Fuel not fun: Reinterpreting attenuated brain responses to reward in obesity.

    Science.gov (United States)

    Kroemer, Nils B; Small, Dana M

    2016-08-01

    There is a well-established literature linking obesity to altered dopamine signaling and brain response to food-related stimuli. Neuroimaging studies frequently report enhanced responses in dopaminergic regions during food anticipation and decreased responses during reward receipt. This has been interpreted as reflecting anticipatory "reward surfeit", and consummatory "reward deficiency". In particular, attenuated response in the dorsal striatum to primary food rewards is proposed to reflect anhedonia, which leads to overeating in an attempt to compensate for the reward deficit. In this paper, we propose an alternative view. We consider brain response to food-related stimuli in a reinforcement-learning framework, which can be employed to separate the contributions of reward sensitivity and reward-related learning that are typically entangled in the brain response to reward. Consequently, we posit that decreased striatal responses to milkshake receipt reflect reduced reward-related learning rather than reward deficiency or anhedonia because reduced reward sensitivity would translate uniformly into reduced anticipatory and consummatory responses to reward. By re-conceptualizing reward deficiency as a shift in learning about subjective value of rewards, we attempt to reconcile neuroimaging findings with the putative role of dopamine in effort, energy expenditure and exploration and suggest that attenuated brain responses to energy dense foods reflect the "fuel", not the fun entailed by the reward. PMID:27085908

  3. Anatomical Atlas-Guided Diffuse Optical Tomography of Brain Activation

    OpenAIRE

    Custo, Anna; Boas, David A.; Tsuzuki, Daisuke; Dan, Ippeita; Mesquita, Rickson; Fischl, Bruce; Grimson, W. Eric L.; Wells, Williams

    2009-01-01

    We describe a neuro imaging protocol that utilizes an anatomical atlas of the human head to guide Diffuse optical tomography of human brain activation. The protocol is demonstrated by imaging the hemodynamic response to median nerve stimulation in three healthy subjects, and comparing the images obtained using a head atlas with the images obtained using the subject-specific head anatomy. The results indicate that using the head atlas anatomy it is possible to reconstruct the location of the b...

  4. A sliding mode observer for hemodynamic characterization under modeling uncertainties

    KAUST Repository

    Zayane, Chadia

    2014-06-01

    This paper addresses the case of physiological states reconstruction in a small region of the brain under modeling uncertainties. The misunderstood coupling between the cerebral blood volume and the oxygen extraction fraction has lead to a partial knowledge of the so-called balloon model describing the hemodynamic behavior of the brain. To overcome this difficulty, a High Order Sliding Mode observer is applied to the balloon system, where the unknown coupling is considered as an internal perturbation. The effectiveness of the proposed method is illustrated through a set of synthetic data that mimic fMRI experiments.

  5. Invasive and transcranial photoacoustic imaging of the vascular response to brain electrical stimulation

    Science.gov (United States)

    Tsytsarev, Vassiliy; Yao, Junjie; Hu, Song; Li, Li; Favazza, Christopher P.; Maslov, Konstantin I.; Wang, Lihong V.

    2010-02-01

    Advances in the brain functional imaging greatly facilitated the understanding of neurovascular coupling. For monitoring of the microvascular response to the brain electrical stimulation in vivo we used optical-resolution photoacoustic microscopy (OR-PAM) through the cranial openings as well as transcranially. Both types of the vascular response, vasoconstriction and vasodilatation, were clearly observed with good spatial and temporal resolution. Obtained results confirm one of the primary points of the neurovascular coupling theory that blood vessels could present vasoconstriction or vasodilatation in response to electrical stimulation, depending on the balance between inhibition and excitation of the different parts of the elements of the neurovascular coupling system.

  6. Toll-like receptor 2 signaling in response to brain injury: an innate bridge to neuroinflammation

    DEFF Research Database (Denmark)

    Babcock, Alicia; Wirenfeldt, Martin; Holm, Thomas;

    2006-01-01

    -mutant mice. Consistent with the fact that responses in knock-out mice had all returned to wild-type levels by 8 d, there was no evidence for effects on neuronal plasticity at 20 d. These results identify a role for TLR2 signaling in the early glial response to brain injury, acting as an innate bridge to...

  7. Repeated BOLD-fMRI imaging of deep brain stimulation responses in rats.

    Science.gov (United States)

    Chao, Tzu-Hao Harry; Chen, Jyh-Horng; Yen, Chen-Tung

    2014-01-01

    Functional magnetic resonance imaging (fMRI) provides a picture of the global spatial activation pattern of the brain. Interest is growing regarding the application of fMRI to rodent models to investigate adult brain plasticity. To date, most rodent studies used an electrical forepaw stimulation model to acquire fMRI data, with α-chloralose as the anesthetic. However, α-chloralose is harmful to animals, and not suitable for longitudinal studies. Moreover, peripheral stimulation models enable only a limited number of brain regions to be studied. Processing between peripheral regions and the brain is multisynaptic, and renders interpretation difficult and uncertain. In the present study, we combined the medetomidine-based fMRI protocol (a noninvasive rodent fMRI protocol) with chronic implantation of an MRI-compatible stimulation electrode in the ventroposterior (VP) thalamus to repetitively sample thalamocortical responses in the rat brain. Using this model, we scanned the forebrain responses evoked by the VP stimulation repeatedly of individual rats over 1 week. Cortical BOLD responses were compared between the 2 profiles obtained at day1 and day8. We discovered reproducible frequency- and amplitude-dependent BOLD responses in the ipsilateral somatosensory cortex (S1). The S1 BOLD responses during the 2 sessions were conserved in maximal response amplitude, area size (size ratio from 0.88 to 0.91), and location (overlap ratio from 0.61 to 0.67). The present study provides a long-term chronic brain stimulation protocol for studying the plasticity of specific neural circuits in the rodent brain by BOLD-fMRI. PMID:24825464

  8. Repeated BOLD-fMRI imaging of deep brain stimulation responses in rats.

    Directory of Open Access Journals (Sweden)

    Tzu-Hao Harry Chao

    Full Text Available Functional magnetic resonance imaging (fMRI provides a picture of the global spatial activation pattern of the brain. Interest is growing regarding the application of fMRI to rodent models to investigate adult brain plasticity. To date, most rodent studies used an electrical forepaw stimulation model to acquire fMRI data, with α-chloralose as the anesthetic. However, α-chloralose is harmful to animals, and not suitable for longitudinal studies. Moreover, peripheral stimulation models enable only a limited number of brain regions to be studied. Processing between peripheral regions and the brain is multisynaptic, and renders interpretation difficult and uncertain. In the present study, we combined the medetomidine-based fMRI protocol (a noninvasive rodent fMRI protocol with chronic implantation of an MRI-compatible stimulation electrode in the ventroposterior (VP thalamus to repetitively sample thalamocortical responses in the rat brain. Using this model, we scanned the forebrain responses evoked by the VP stimulation repeatedly of individual rats over 1 week. Cortical BOLD responses were compared between the 2 profiles obtained at day1 and day8. We discovered reproducible frequency- and amplitude-dependent BOLD responses in the ipsilateral somatosensory cortex (S1. The S1 BOLD responses during the 2 sessions were conserved in maximal response amplitude, area size (size ratio from 0.88 to 0.91, and location (overlap ratio from 0.61 to 0.67. The present study provides a long-term chronic brain stimulation protocol for studying the plasticity of specific neural circuits in the rodent brain by BOLD-fMRI.

  9. Obesity and the Role of Short Duration Submaximal Work on Cardiovascular and Cerebral Hemodynamics

    OpenAIRE

    Cavuoto, Lora A.; Maikala, Rammohan V.

    2016-01-01

    The objective of this study was to compare gas exchange, cardiac and cerebral hemodynamic responses between 10 non-obese and 10 obese men during submaximal work. With the increasing prevalence of obesity, there is a need to understand the impact of obesity on work-induced responses. Participants completed a step-wise incremental cycling until they reached 60% of their age-predicted maximum heart rate. Gas exchange, cardiac and pre-frontal cortex hemodynamic responses were simultaneously measu...

  10. Sensation Seeking Predicts Brain Responses in the Old-New Task: Converging Multimodal Neuroimaging Evidence

    OpenAIRE

    Lawson, Adam L.; Liu, Xun; Joseph, Jane; Vagnini, Victoria L.; Kelly, Thomas H.; Jiang, Yang

    2012-01-01

    Novel images and message content enhance visual attention and memory for high sensation seekers, but the neural mechanisms associated with this effect are unclear. To investigate the individual differences in brain responses to new and old (studied) visual stimuli, we utilized Event-related Potentials (ERP) and functional Magnetic Resonance Imaging (fMRI) measures to examine brain reactivity among high and low sensation seekers during a classic old-new memory recognition task. Twenty low and ...

  11. Evaluation of Auditory Brain Stems Evoked Response in Newborns With Pathologic Hyperbilirubinemia in Mashhad, Iran

    OpenAIRE

    Okhravi, Tooba; Tarvij Eslami, Saeedeh; Hushyar Ahmadi, Ali; Nassirian, Hossain; Najibpour, Reza

    2015-01-01

    Background: Neonatal jaundice is a common cause of sensorneural hearing loss in children. Objectives: We aimed to detect the neurotoxic effects of pathologic hyperbilirubinemia on brain stem and auditory tract by auditory brain stem evoked response (ABR) which could predict early effects of hyperbilirubinemia. Patients and Methods: This case-control study was performed on newborns with pathologic hyperbilirubinemia. The inclusion criteria were healthy term and near term (35 - 37 weeks) newbor...

  12. CacyBP/SIP as a regulator of transcriptional responses in brain cells

    OpenAIRE

    Kilanczyk, Ewa; Filipek, Anna; Hetman, Michal

    2014-01-01

    The Calcyclin-Binding Protein/Siah-1-Interacting Protein (CacyBP/SIP) is highly expressed in the brain and was shown to regulate the β-catenin-driven transcription in thymocytes. Therefore, it was investigated whether in brain cells CacyBP/SIP might play a role as a transcriptional regulator. In BDNF- or forskolin-stimulated rat primary cortical neurons, overexpression of CacyBP/SIP enhanced transcriptional activity of the cAMP-response element (CRE). In addition, overexpressed...

  13. Perfusion and Volume Response of Canine Brain Tumors to Stereotactic Radiosurgery and Radiotherapy.

    OpenAIRE

    Zwingenberger, AL; Pollard, RE; Taylor, SL; Chen, RX; Nunley, J; Kent, MS

    2016-01-01

    Stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT) are highly conformal, high-dose radiation treatment techniques used to treat people and dogs with brain tumors.To evaluate the response to SRS- and SRT-treated tumors using volume and perfusion variables and to measure the survival times of affected dogs.Prospective study of 34 dogs with evidence of brain tumors undergoing stereotactic radiosurgery (SRS) or stereotactic radiotherapy (SRT).Computed tomography and MRI imaging w...

  14. Effects of Oxytocin and Prosocial Behavior on Brain Responses to Direct and Vicariously Experienced Pain

    OpenAIRE

    Singer, Tania; Snozzi, Romana; Bird, Geoffrey; Petrovic, Predrag; Silani, Giorgia; Heinrichs, Markus; Dolan, Raymond J.

    2008-01-01

    In this study, we tested the validity of 2 popular assumptions about empathy: (a) empathy can be enhanced by oxytocin, a neuropeptide known to be crucial in affiliative behavior, and (b) individual differences in prosocial behavior are positively associated with empathic brain responses. To do so, we measured brain activity in a double-blind placebo-controlled study of 20 male participants either receiving painful stimulation to their own hand (self condition) or observing their female partne...

  15. Time-Frequency Characterization of Cerebral Hemodynamics of Migraine Sufferers as Assessed by NIRS Signals

    Directory of Open Access Journals (Sweden)

    Filippo Molinari

    2010-01-01

    Full Text Available Near-infrared spectroscopy (NIRS is a noninvasive system for the real-time monitoring of the concentration of oxygenated (O2Hb and reduced (HHb hemoglobin in the brain cortex. O2Hb and HHb concentrations vary in response to cerebral autoregulation. Sixty-eight women (14 migraineurs without aura, 49 migraineurs with aura, and 5 controls performed breath-holding and hyperventilation during NIRS recordings. Signals were processed using the Choi-Williams time-frequency transform in order to measure the power variation of the very-low frequencies (VLF: 20–40 mHz and of the low frequencies (LF: 40–140 mHz. Results showed that migraineurs without aura present different LF and VLF power levels than controls and migraineurs with aura. The accurate power measurement of the time-frequency analysis allowed for the discrimination of the subjects' hemodynamic patterns. The time-frequency analysis of NIRS signals can be used in clinical practice to assess cerebral hemodynamics.

  16. A study of brain MRI findings and clinical response of bladder empting failure in brain bladder

    Energy Technology Data Exchange (ETDEWEB)

    Miyakoda, Keiichi (Yamashina Aiseikai Hospital, Kyoto (Japan)); Watanabe, Kousuke

    1993-02-01

    In 45 patients (38 males and 7 females; average age:78 years) with brain bladder, who did not have any peripheral neuropathies and spinal disturbance, cerebral findings of MRI (1.5 T) T[sub 2] enhanced image were analyzed in comparison with those of 7 control patients with normal urination after BPH operations. Patients with neurogenic bladder were divided into three groups as follows: 33 patients with a chief complaint of urinary disturbance (Group I), 9 patients with urinary incontinence (Group II) and 3 patients with balanced bladder (Group III). High frequency of lacune (24%) of the globus pallidus and low signalling of the corpus striatum (30%) was found in Group I patients, but low frequency in other Group patients and control patients. Furthermore, pathologic changes with various grades in the globus pallidus were observed in 91% of Group I patients. In the treatment of urinary disturbance, a high improvement rate of micturition disorder (77%) was obtained in patients treated with a combination of dantrolene and TURp (TUIbn for females). However, patients who had clear lacune of the globus pallidus showed the low improvement rate. It should be possible that the globus pallidus contributes to control the movement of the external sphincter and the pelvic base muscles as well as other striated muscles. Moreover, lacune was rarely found in the urination center of the brain-stem on MRI. (author).

  17. Comprehensive cognitive and cerebral hemodynamic evaluation after cranioplasty

    Directory of Open Access Journals (Sweden)

    Coelho F

    2014-05-01

    Full Text Available Fernanda Coelho,1 Arthur Maynart Oliveira,2 Wellingson Silva Paiva,2 Fabio Rios Freire,1 Vanessa Tome Calado,1 Robson Luis Amorim,2 Iuri Santana Neville,2 Almir Ferreira de Andrade,2 Edson Bor-Seng-Shu,3 Renato Anghinah,1 Manoel Jacobsen Teixeira21Neurorehabilitation Group, Division of Neurology, 2Division of Neurosurgery, 3Neurosonology and Cerebral Hemodynamics Group, University of São Paulo Medical School, São Paulo, BrazilAbstract: Decompressive craniectomy is an established procedure to lower intracranial pressure and can save patients' lives. However, this procedure is associated with delayed cognitive decline and cerebral hemodynamics complications. Studies show the benefits of cranioplasty beyond cosmetic aspects, including brain protection, and functional and cerebrovascular aspects, but a detailed description of the concrete changes following this procedure are lacking. In this paper, the authors report a patient with trephine syndrome who underwent cranioplasty; comprehensive cognitive and cerebral hemodynamic evaluations were performed prior to and following the cranioplasty. The discussion was based on a critical literature review.Keywords: cranioplasty, decompressive craniotomy, perfusion CT, traumatic brain injury, cognition, neuropsychological test

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

    Science.gov (United States)

    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. PMID:27516598

  19. Effect of lighting conditions on brain network complexity associated with response learning.

    Science.gov (United States)

    Fidalgo, Camino; Conejo, Nélida M; González-Pardo, Héctor; Arias, Jorge L

    2013-10-25

    Several studies have reported the brain regions involved in response learning. However, there is discrepancy regarding the lighting conditions in the experimental setting (i.e. under dark or light conditions). In this regard, it would be relevant to know if the presence/absence of visual cues in the environment has any effect in the brain networks involved in a response learning task. Animals were trained in a water T-maze under two different lighting conditions (light versus dark). All subjects reached the learning criterion of 80% correct arm choices. Quantitative cytochrome oxidase (CO) histochemistry was used as a metabolic brain mapping technique. Our results show that the ventral hippocampus and the parietal cortex are associated with the acquisition of a response learning task regardless of lighting conditions. In addition, when the same task is run in the dark, widespread recruitment of structures involving cortical, limbic and striatal regions was found. PMID:24084195

  20. Hemodynamic and radionuclide ventriculography changes in response to intravenous captopril and digoxin and their combinations in patients with severe heart failure

    International Nuclear Information System (INIS)

    It is shown that radionuclide ventriculography is not a reliable indicator of treatment response in patients with hearth failure and a severely depressed left ventricular ejection fraction. (author). 12 refs.; 14 figs

  1. Time evolution and hemodynamics of cerebral aneurysms

    Science.gov (United States)

    Sforza, Daniel M.; Putman, Christopher; Tateshima, Satoshi; Viñuela, Fernando; Cebral, Juan

    2011-03-01

    Cerebral aneurysm rupture is a leading cause of hemorrhagic strokes. Because they are being more frequently diagnosed before rupture and the prognosis of subarachnoid hemorrhage is poor, clinicians are often required to judge which aneurysms are prone to progression and rupture. Unfortunately, the processes of aneurysm initiation, growth and rupture are not well understood. Multiple factors associated to these processes have been identified. Our goal is to investigate two of them, arterial hemodynamics (using computational fluid dynamics) and the peri-aneurysmal environment, by studying a group of growing cerebral aneurysms that are followed longitudinally in time. Six patients with unruptured untreated brain aneurysms which exhibited growth during the observation period were selected for the study. Vascular models of each aneurysm at each observation time were constructed from the corresponding computed tomography angiography (CTA) images. Subsequently, models were aligned, and geometrical differences quantified. Blood flow was modeled with the 3D unsteady incompressible Navier-Stokes equation for a Newtonian fluid, and wall shear stress distribution and flow patterns were calculated and visualized. Analysis of the simulations and changes in geometry revealed asymmetric growth patterns and suggests that areas subject to vigorous flows, i.e. relative high wall shear stress and concentrated streamlines patterns; correspond to regions of aneurysm growth. Furthermore, in some cases the geometrical evolution of aneurysms is clearly affected by contacts with bone structures and calcifications in the wall, and as a consequence the hemodynamics is greatly modified. Thus, in these cases the peri-aneurysmal environment must be considered when analyzing aneurysm evolution.

  2. The response of the brain tissue to DNA double strand breaks

    International Nuclear Information System (INIS)

    Double-strand breaks (DSB) are the most deleterious form of DNA damage after ionizing radiation, the response of the brain tissue to DNA damage is related to the developmental dynamics of this system. Homology recombination is particularly important for proliferating cells, while non-homologous end joining is critical for differentiating cells. Defects in the related factors to DNA damage pathway underpin many human genopathy with neuropathology. Reviewed the signal conduction system involved in the DNA DSB response and human neuropathology genopathy related to DNA DSB factors deficiencies in the brain cells. (authors)

  3. Effect of glutamate on inflammatory responses of intestine and brain after focal cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Lei Xu; Jie Sun; Ran Lu; Qing Ji; Jian-Guo Xu

    2005-01-01

    AIM: To study the modulation of glutamate on post-ischemic intestinal and cerebral inflammatory responses in a ischemic and excitotoxic rat model.METHODS: Adult male rats were subjected to bilateral carotid artery occlusion for 15 min and injection of monosodium glutamate intraperitoneally, to decapitate them at selected time points. Tumor necrosis factor alpha (TNF-α) level and nuclear factor kappa B (NF-κB) activity were determined by enzyme-linked immunosorbant assay (ELISA) and electrophoretic mobility shift assay (EMSA), respectively.Hemodynamic parameters were monitored continuously during the whole process of cerebral ischemia and reperfusion.RESULTS: Monosodium glutamate (MSG) treated rats displayed statistically significant high levels of TNF-α in cerebral and intestinal tissuess within the first 6 h of ischemia. The rats with cerebral ischemia showed a minor decrease of TNF-α production in cerebral and intestinal tissuess. The rats with cerebral ischemia and treated with MSG displayed statistically significant low levels of TNF-α in cerebral and intestinal tissues. These results correlated significantly with NF-κB production calculated at the same intervals. During experiment, the mean blood pressure and heart rates in all groups were stable.CONCLUSION: Glutamate is involved in the mechanism of intestinal and cerebral inflammation responses. The effects of glutamate on cerebral and intestinal inflammatory responses after ischemia are up-regulated at the transcriptional level,through the NF-κB signal transduction pathway.

  4. Finite element modeling of human brain response to football helmet impacts.

    Science.gov (United States)

    Darling, T; Muthuswamy, J; Rajan, S D

    2016-10-01

    The football helmet is used to help mitigate the occurrence of impact-related traumatic (TBI) and minor traumatic brain injuries (mTBI) in the game of American football. While the current helmet design methodology may be adequate for reducing linear acceleration of the head and minimizing TBI, it however has had less effect in minimizing mTBI. The objectives of this study are (a) to develop and validate a coupled finite element (FE) model of a football helmet and the human body, and (b) to assess responses of different regions of the brain to two different impact conditions - frontal oblique and crown impact conditions. The FE helmet model was validated using experimental results of drop tests. Subsequently, the integrated helmet-human body FE model was used to assess the responses of different regions of the brain to impact loads. Strain-rate, strain, and stress measures in the corpus callosum, midbrain, and brain stem were assessed. Results show that maximum strain-rates of 27 and 19 s(-1) are observed in the brain-stem and mid-brain, respectively. This could potentially lead to axonal injuries and neuronal cell death during crown impact conditions. The developed experimental-numerical framework can be used in the study of other helmet-related impact conditions. PMID:26867124

  5. Correlation of auditory brain stem response and the MRI measurements in neuro-degenerative disorders

    Energy Technology Data Exchange (ETDEWEB)

    Kamei, Hidekazu (Tokyo Women' s Medical Coll. (Japan))

    1989-06-01

    The purpose of this study is to elucidate correlations of several MRI measurements of the cranium and brain, functioning as a volume conductor, to the auditory brain stem response (ABR) in neuro-degenerative disorders. The subjects included forty-seven patients with spinocerebellar degeneration (SCD) and sixteen of amyotrophic lateral sclerosis (ALS). Statistically significant positive correlations were found between I-V and III-V interpeak latencies (IPLs) and the area of cranium and brain in the longitudinal section of SCD patients, and between I-III and III-V IPLs and the area in the longitudinal section of those with ALS. And, also there were statistically significant correlations between the amplitude of the V wave and the area of brain stem as well as that of the cranium in the longitudinal section of SCD patients, and between the amplitude of the V wave and the area of the cerebrum in the longitudinal section of ALS. In conclusion, in the ABR, the IPLs were prolonged and the amplitude of the V wave was decreased while the MRI size of the cranium and brain increased. When the ABR is applied to neuro-degenerative disorders, it might be important to consider not only the conduction of the auditory tracts in the brain stem, but also the correlations of the size of the cranium and brain which act as a volume conductor. (author).

  6. Correlation of auditory brain stem response and the MRI measurements in neuro-degenerative disorders

    International Nuclear Information System (INIS)

    The purpose of this study is to elucidate correlations of several MRI measurements of the cranium and brain, functioning as a volume conductor, to the auditory brain stem response (ABR) in neuro-degenerative disorders. The subjects included forty-seven patients with spinocerebellar degeneration (SCD) and sixteen of amyotrophic lateral sclerosis (ALS). Statistically significant positive correlations were found between I-V and III-V interpeak latencies (IPLs) and the area of cranium and brain in the longitudinal section of SCD patients, and between I-III and III-V IPLs and the area in the longitudinal section of those with ALS. And, also there were statistically significant correlations between the amplitude of the V wave and the area of brain stem as well as that of the cranium in the longitudinal section of SCD patients, and between the amplitude of the V wave and the area of the cerebrum in the longitudinal section of ALS. In conclusion, in the ABR, the IPLs were prolonged and the amplitude of the V wave was decreased while the MRI size of the cranium and brain increased. When the ABR is applied to neuro-degenerative disorders, it might be important to consider not only the conduction of the auditory tracts in the brain stem, but also the correlations of the size of the cranium and brain which act as a volume conductor. (author)

  7. Cerebral versus systemic hemodynamics during graded orthostatic stress in humans

    Science.gov (United States)

    Levine, B. D.; Giller, C. A.; Lane, L. D.; Buckey, J. C.; Blomqvist, C. G.

    1994-01-01

    BACKGROUND: Orthostatic syncope is usually attributed to cerebral hypoperfusion secondary to systemic hemodynamic collapse. Recent research in patients with neurocardiogenic syncope has suggested that cerebral vasoconstriction may occur during orthostatic hypotension, compromising cerebral autoregulation and possibly contributing to the loss of consciousness. However, the regulation of cerebral blood flow (CBF) in such patients may be quite different from that of healthy individuals, particularly when assessed during the rapidly changing hemodynamic conditions associated with neurocardiogenic syncope. To be able to interpret the pathophysiological significance of these observations, a clear understanding of the normal responses of the cerebral circulation to orthostatic stress must be obtained, particularly in the context of the known changes in systemic and regional distributions of blood flow and vascular resistance during orthostasis. Therefore, the specific aim of this study was to examine the changes that occur in the cerebral circulation during graded reductions in central blood volume in the absence of systemic hypotension in healthy humans. We hypothesized that cerebral vasoconstriction would occur and CBF would decrease due to activation of the sympathetic nervous system. We further hypothesized, however, that the magnitude of this change would be small compared with changes in systemic or skeletal muscle vascular resistance in healthy subjects with intact autoregulation and would be unlikely to cause syncope without concomitant hypotension. METHODS AND RESULTS: To test this hypothesis, we studied 13 healthy men (age, 27 +/- 7 years) during progressive lower body negative pressure (LBNP). We measured systemic flow (Qc is cardiac output; C2H2 rebreathing), regional forearm flow (FBF; venous occlusion plethysmography), and blood pressure (BP; Finapres) and calculated systemic (SVR) and forearm (FVR) vascular resistances. Changes in brain blood flow were

  8. Endogenous neurogenic cell response in the mature mammalian brain following traumatic injury.

    Science.gov (United States)

    Sun, Dong

    2016-01-01

    In the mature mammalian brain, new neurons are generated throughout life in the neurogenic regions of the subventricular zone (SVZ) and the dentate gyrus (DG) of the hippocampus. Over the past two decades, extensive studies have examined the extent of adult neurogenesis in the SVZ and DG, the role of the adult generated new neurons in normal brain function and the underlying mechanisms regulating the process of adult neurogenesis. The extent and the function of adult neurogenesis under neuropathological conditions have also been explored in varying types of disease models in animals. Increasing evidence has indicated that these endogenous neural stem/progenitor cells may play regenerative and reparative roles in response to CNS injuries or diseases. This review will discuss the potential functions of adult neurogenesis in the injured brain and will describe the recent development of strategies aimed at harnessing this neurogenic capacity in order to repopulate and repair the injured brain following trauma. PMID:25936874

  9. Children's Brain Responses to Optic Flow Vary by Pattern Type and Motion Speed.

    Directory of Open Access Journals (Sweden)

    Rick O Gilmore

    Full Text Available Structured patterns of global visual motion called optic flow provide crucial information about an observer's speed and direction of self-motion and about the geometry of the environment. Brain and behavioral responses to optic flow undergo considerable postnatal maturation, but relatively little brain imaging evidence describes the time course of development in motion processing systems in early to middle childhood, a time when psychophysical data suggest that there are changes in sensitivity. To fill this gap, electroencephalographic (EEG responses were recorded in 4- to 8-year-old children who viewed three time-varying optic flow patterns (translation, rotation, and radial expansion/contraction at three different speeds (2, 4, and 8 deg/s. Modulations of global motion coherence evoked coherent EEG responses at the first harmonic that differed by flow pattern and responses at the third harmonic and dot update rate that varied by speed. Pattern-related responses clustered over right lateral channels while speed-related responses clustered over midline channels. Both children and adults show widespread responses to modulations of motion coherence at the second harmonic that are not selective for pattern or speed. The results suggest that the developing brain segregates the processing of optic flow pattern from speed and that an adult-like pattern of neural responses to optic flow has begun to emerge by early to middle childhood.

  10. Children's Brain Responses to Optic Flow Vary by Pattern Type and Motion Speed.

    Science.gov (United States)

    Gilmore, Rick O; Thomas, Amanda L; Fesi, Jeremy

    2016-01-01

    Structured patterns of global visual motion called optic flow provide crucial information about an observer's speed and direction of self-motion and about the geometry of the environment. Brain and behavioral responses to optic flow undergo considerable postnatal maturation, but relatively little brain imaging evidence describes the time course of development in motion processing systems in early to middle childhood, a time when psychophysical data suggest that there are changes in sensitivity. To fill this gap, electroencephalographic (EEG) responses were recorded in 4- to 8-year-old children who viewed three time-varying optic flow patterns (translation, rotation, and radial expansion/contraction) at three different speeds (2, 4, and 8 deg/s). Modulations of global motion coherence evoked coherent EEG responses at the first harmonic that differed by flow pattern and responses at the third harmonic and dot update rate that varied by speed. Pattern-related responses clustered over right lateral channels while speed-related responses clustered over midline channels. Both children and adults show widespread responses to modulations of motion coherence at the second harmonic that are not selective for pattern or speed. The results suggest that the developing brain segregates the processing of optic flow pattern from speed and that an adult-like pattern of neural responses to optic flow has begun to emerge by early to middle childhood. PMID:27326860

  11. Chronic monitoring of cortical hemodynamics in behaving, freely-moving rats using a miniaturized head-mounted optical microscope

    Science.gov (United States)

    Sigal, Iliya; Gad, Raanan; Koletar, Margaret; Ringuette, Dene; Stefanovic, Bojana; Levi, Ofer

    2016-03-01

    Growing interest within the neurophysiology community in assessing healthy and pathological brain activity in animals that are awake and freely-behaving has triggered the need for optical systems that are suitable for such longitudinal studies. In this work we report label-free multi-modal imaging of cortical hemodynamics in the somatosensory cortex of awake, freely-behaving rats, using a novel head-mounted miniature optical microscope. The microscope employs vertical cavity surface emitting lasers (VCSELs) at three distinct wavelengths (680 nm, 795 nm, and 850 nm) to provide measurements of four hemodynamic markers: blood flow speeds, HbO, HbR, and total Hb concentration, across a > 2 mm field of view. Blood flow speeds are extracted using Laser Speckle Contrast Imaging (LSCI), while oxygenation measurements are performed using Intrinsic Optical Signal Imaging (IOSI). Longitudinal measurements on the same animal are made possible over the course of > 6 weeks using a chronic window that is surgically implanted into the skull. We use the device to examine changes in blood flow and blood oxygenation in superficial cortical blood vessels and tissue in response to drug-induced absence-like seizures, correlating motor behavior with changes in blood flow and blood oxygenation in the brain.

  12. Hemodynamic Changes in Blood Donors

    Directory of Open Access Journals (Sweden)

    M Rafiei

    2004-07-01

    Full Text Available Introduction: Everyday, millions of people around the world go through phlebotomy, either to donate blood or for therapeutic intention. The most important worrisome adverse effects are hemodynamic alterations. In this study, hemodynamic changes following blood donation were assessed. Methods & Materials: Three hundred laborers who donated blood voluntarily were enrolled in this study. Blood pressure (BP and pulse rate were measured before the procedure, ten minutes afterwards, and one week following phlebotomy. Hemoglobin (Hgb and hematocrit (Hct were also determined prior to and one week after phlebotomy. Finally, results before and after donation were compared with each other. Results: 242 volunteers had normal BP and 58 were hypertensive. The mean systolic blood pressures (SBP before phlebotomy, ten minutes after the procedure, and one week later were 120, 117, and 122 mmHg, respectively. During the same periods of time, the mean of diastolic blood pressures (DBP were 77 , 78 and 78 mmHg , in order , while pulse rates on average were 80 , 82 and 76 beats/minute . None of the aforementioned changes were clinically significant. After one week, Hgb decreased by about 0.3 g/dl (P<0.001 and Hct declined on average of 1.7 (P<0.001. Forty six individuals had high DBP and one week after donation, their DBP was reduced by 7 mmHg. Age, body mass index and smoking did not have any significant effect on hemodynamic status. Conclusion: Hemodynamic changes in healthy blood donors were not clinically significant. It seems that DBP drops desirably in hypertensive individuals. This needs to be evaluated more carefully in future studies.

  13. Hemodynamic changes in depressive patients

    OpenAIRE

    Ma, Ying; Li, Hui-Chun; Zheng, Lei-lei; Yu, Hua-liang

    2006-01-01

    Objective: This study is aimed at exploring the relationship between hemodynamic changes and depressive and anxious symptom in depression patients. Methods: The cardiac function indices including the left stroke index (LSI), ejection fraction (EF), heart rate (HR), diastolic pressure mean (DPM), systolic pressure mean (SPM), left ventricle end-diastolic volume (LVDV), effective circulating volume (ECV), resistance total mean (RTM) and blood flow smooth degree (BFSD) were determined in 65 pati...

  14. Computational Analysis of Cardiovascular Hemodynamics

    OpenAIRE

    Eun Bo Shim; Thomas Heldt; Akira Amano; Kyehan Rhee

    2012-01-01

    The human body requires a complex circulatory system to supply nutrients to, and to remove metabolic waste products from, its tissues. Given this primary purpose, circulatory function is closely related to the hemodynamic characteristics of blood vessels. This includes not only macroscale fluid dynamics, but also mass transfer in the microvasculature. Many experimental and clinical studies have examined these characteristics of vascular function. Over the past 50 years, mathematical modeling ...

  15. Brain responses to acupuncture stimulation in the prosthetic hand of an amputee patient.

    Science.gov (United States)

    Lee, In-Seon; Jung, Won-Mo; Lee, Ye-Seul; Wallraven, Christian; Chae, Younbyoung

    2015-10-01

    This report describes the brain responses to acupuncture in an upper limb amputee patient. A 62-year-old male had previously undergone a lower left arm amputation following an electrical accident. Using functional MRI, we investigated brain responses to acupuncture stimulation in the aforementioned amputee under three conditions: (a) intact hand, (b) prosthetic hand (used by the patient), and (c) fake fabric hand. The patient described greater de qi sensation when he received acupuncture stimulation in his prosthetic hand compared to a fake hand, with both stimulations performed in a similar manner. We found enhanced brain activation in the insula and sensorimotor cortex in response to acupuncture stimulation in the amputee's prosthetic hand, while there was only minimal activation in the visual cortex in response to acupuncture stimulation in a fake hand. The enhanced brain responses to acupuncture stimulation of the patient's prosthetic hand might be derived from cortical reorganisation, as he has been using his prosthetic hand for over 40 years. Our findings suggest the possible use of acupuncture stimulation in a prosthetic hand as an enhanced sensory feedback mechanism, which may represent a new treatment approach for phantom limb pain. PMID:26033865

  16. Impact of Intra-Extracranial Hemodynamics on Cerebral Ischemia by Arterial Hypertension (Part 2

    Directory of Open Access Journals (Sweden)

    Alexander G. Kruglov, PhD, ScD

    2012-06-01

    Full Text Available The association between hemodynamic and biochemical parameters of cerebral blood flow have been studied in man, using mathematical methods of statistics. The values have been obtained through catheterization using a probe jammed at the level of the bulb of the superior jugular vein. Relationships with central hemodynamic parameters have been evaluated, including the right atrium, the right ventricle, and the left ventricle, as well as with pressure and biochemical values of the arterial bed. Data have been acquired in patients with stable arterial hypertension. Analysis of all relationship between hemodynamic and biochemical parameters has shown that the uniform hemodynamic zone: Sin.P. – SJV – SEV – the right atrium, normally participates in regulation of gaseous exchange in the human brain depending on the minimum pressure on the way of outflow from the brain. In stable arterial hypertension, this type of regulation is lost. On the basis of the results of this study, it has been concluded that blood viscosity is normally a primary controlled parameter of homeostasis. In stable arterial hypertension, homeostatic control of factors determining rheological and thrombogenic properties of blood, as well as participating in the development of brain ischemic conditions is lost. This increases risk of disturbances in central hemodynamics.

  17. Tunicamycin-induced unfolded protein response in the developing mouse brain

    International Nuclear Information System (INIS)

    Accumulation of unfolded or misfolded proteins in the endoplasmic reticulum (ER) causes ER stress, resulting in the activation of the unfolded protein response (UPR). ER stress and UPR are associated with many neurodevelopmental and neurodegenerative disorders. The developing brain is particularly susceptible to environmental insults which may cause ER stress. We evaluated the UPR in the brain of postnatal mice. Tunicamycin, a commonly used ER stress inducer, was administered subcutaneously to mice of postnatal days (PDs) 4, 12 and 25. Tunicamycin caused UPR in the cerebral cortex, hippocampus and cerebellum of mice of PD4 and PD12, which was evident by the upregulation of ATF6, XBP1s, p-eIF2α, GRP78, GRP94 and MANF, but failed to induce UPR in the brain of PD25 mice. Tunicamycin-induced UPR in the liver was observed at all stages. In PD4 mice, tunicamycin-induced caspase-3 activation was observed in layer II of the parietal and optical cortex, CA1–CA3 and the subiculum of the hippocampus, the cerebellar external germinal layer and the superior/inferior colliculus. Tunicamycin-induced caspase-3 activation was also shown on PD12 but to a much lesser degree and mainly located in the dentate gyrus of the hippocampus, deep cerebellar nuclei and pons. Tunicamycin did not activate caspase-3 in the brain of PD25 mice and the liver of all stages. Similarly, immature cerebellar neurons were sensitive to tunicamycin-induced cell death in culture, but became resistant as they matured in vitro. These results suggest that the UPR is developmentally regulated and the immature brain is more susceptible to ER stress. - Highlights: • Tunicamycin caused a development-dependent UPR in the mouse brain. • Immature brain was more susceptible to tunicamycin-induced endoplasmic reticulum stress. • Tunicamycin caused more neuronal death in immature brain than mature brain. • Tunicamycin-induced neuronal death is region-specific

  18. Tunicamycin-induced unfolded protein response in the developing mouse brain

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Haiping; Wang, Xin [Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Ke, Zun-Ji [Department of Biochemistry, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203 (China); Comer, Ashley L.; Xu, Mei; Frank, Jacqueline A. [Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Zhang, Zhuo; Shi, Xianglin [Graduate Center for Toxicology, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Luo, Jia, E-mail: jialuo888@uky.edu [Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536 (United States)

    2015-03-15

    Accumulation of unfolded or misfolded proteins in the endoplasmic reticulum (ER) causes ER stress, resulting in the activation of the unfolded protein response (UPR). ER stress and UPR are associated with many neurodevelopmental and neurodegenerative disorders. The developing brain is particularly susceptible to environmental insults which may cause ER stress. We evaluated the UPR in the brain of postnatal mice. Tunicamycin, a commonly used ER stress inducer, was administered subcutaneously to mice of postnatal days (PDs) 4, 12 and 25. Tunicamycin caused UPR in the cerebral cortex, hippocampus and cerebellum of mice of PD4 and PD12, which was evident by the upregulation of ATF6, XBP1s, p-eIF2α, GRP78, GRP94 and MANF, but failed to induce UPR in the brain of PD25 mice. Tunicamycin-induced UPR in the liver was observed at all stages. In PD4 mice, tunicamycin-induced caspase-3 activation was observed in layer II of the parietal and optical cortex, CA1–CA3 and the subiculum of the hippocampus, the cerebellar external germinal layer and the superior/inferior colliculus. Tunicamycin-induced caspase-3 activation was also shown on PD12 but to a much lesser degree and mainly located in the dentate gyrus of the hippocampus, deep cerebellar nuclei and pons. Tunicamycin did not activate caspase-3 in the brain of PD25 mice and the liver of all stages. Similarly, immature cerebellar neurons were sensitive to tunicamycin-induced cell death in culture, but became resistant as they matured in vitro. These results suggest that the UPR is developmentally regulated and the immature brain is more susceptible to ER stress. - Highlights: • Tunicamycin caused a development-dependent UPR in the mouse brain. • Immature brain was more susceptible to tunicamycin-induced endoplasmic reticulum stress. • Tunicamycin caused more neuronal death in immature brain than mature brain. • Tunicamycin-induced neuronal death is region-specific.

  19. Hemodynamic and Light-Scattering Changes of Rat Spinal Cord and Primary Somatosensory Cortex in Response to Innocuous and Noxious Stimuli

    Directory of Open Access Journals (Sweden)

    Ji-Wei He

    2015-09-01

    Full Text Available Neuroimaging technologies with an exceptional spatial resolution and noninvasiveness have become a powerful tool for assessing neural activity in both animals and humans. However, the effectiveness of neuroimaging for pain remains unclear partly because the neurovascular coupling during pain processing is not completely characterized. Our current work aims to unravel patterns of neurovascular parameters in pain processing. A novel fiber-optic method was used to acquire absolute values of regional oxy- (HbO and deoxy-hemoglobin concentrations, oxygen saturation rates (SO2, and the light-scattering coefficients from the spinal cord and primary somatosensory cortex (SI in 10 rats. Brief mechanical and electrical stimuli (ranging from innocuous to noxious intensities as well as a long-lasting noxious stimulus (formalin injection were applied to the hindlimb under pentobarbital anesthesia. Interhemispheric comparisons in the spinal cord and SI were used to confirm functional activation during sensory processing. We found that all neurovascular parameters showed stimulation-induced changes; however, patterns of changes varied with regions and stimuli. Particularly, transient increases in HbO and SO2 were more reliably attributed to brief stimuli, whereas a sustained decrease in SO2 was more reliably attributed to formalin. Only the ipsilateral SI showed delayed responses to brief stimuli. In conclusion, innocuous and noxious stimuli induced significant neurovascular responses at critical centers (e.g., the spinal cord and SI along the somatosensory pathway; however, there was no single response pattern (as measured by amplitude, duration, lateralization, decrease or increase that was able to consistently differentiate noxious stimuli. Our results strongly suggested that the neurovascular response patterns differ between brief and long-lasting noxious stimuli, and can also differ between the spinal cord and SI. Therefore, a use of multiple

  20. Brain connectivity reflects human aesthetic responses to music.

    Science.gov (United States)

    Sachs, Matthew E; Ellis, Robert J; Schlaug, Gottfried; Loui, Psyche

    2016-06-01

    Humans uniquely appreciate aesthetics, experiencing pleasurable responses to complex stimuli that confer no clear intrinsic value for survival. However, substantial variability exists in the frequency and specificity of aesthetic responses. While pleasure from aesthetics is attributed to the neural circuitry for reward, what accounts for individual differences in aesthetic reward sensitivity remains unclear. Using a combination of survey data, behavioral and psychophysiological measures and diffusion tensor imaging, we found that white matter connectivity between sensory processing areas in the superior temporal gyrus and emotional and social processing areas in the insula and medial prefrontal cortex explains individual differences in reward sensitivity to music. Our findings provide the first evidence for a neural basis of individual differences in sensory access to the reward system, and suggest that social-emotional communication through the auditory channel may offer an evolutionary basis for music making as an aesthetically rewarding function in humans. PMID:26966157

  1. Prostaglandin E2 in Brain-mediated Illness Responses

    OpenAIRE

    Elander, Louise

    2010-01-01

    We are unceasingly exposed to potentially harmful microorganisms. The battle against threatening infectious agents includes activation of both the innate and of the adaptive immune systems. Illness responses are elicited and include inflammation, fever, decreased appetite, lethargy and increased sensitivity to painful stimuli in order to defeat invaders. While many of these signs of disease are controlled by the central nervous system, it has remained an enigma how signals from the peripheral...

  2. Another kind of 'BOLD Response': answering multiple-choice questions via online decoded single-trial brain signals.

    Science.gov (United States)

    Sorger, Bettina; Dahmen, Brigitte; Reithler, Joel; Gosseries, Olivia; Maudoux, Audrey; Laureys, Steven; Goebel, Rainer

    2009-01-01

    The term 'locked-in'syndrome (LIS) describes a medical condition in which persons concerned are severely paralyzed and at the same time fully conscious and awake. The resulting anarthria makes it impossible for these patients to naturally communicate, which results in diagnostic as well as serious practical and ethical problems. Therefore, developing alternative, muscle-independent communication means is of prime importance. Such communication means can be realized via brain-computer interfaces (BCIs) circumventing the muscular system by using brain signals associated with preserved cognitive, sensory, and emotional brain functions. Primarily, BCIs based on electrophysiological measures have been developed and applied with remarkable success. Recently, also blood flow-based neuroimaging methods, such as functional magnetic resonance imaging (fMRI) and functional near-infrared spectroscopy (fNIRS), have been explored in this context. After reviewing recent literature on the development of especially hemodynamically based BCIs, we introduce a highly reliable and easy-to-apply communication procedure that enables untrained participants to motor-independently and relatively effortlessly answer multiple-choice questions based on intentionally generated single-trial fMRI signals that can be decoded online. Our technique takes advantage of the participants' capability to voluntarily influence certain spatio-temporal aspects of the blood oxygenation level-dependent (BOLD) signal: source location (by using different mental tasks), signal onset and offset. We show that healthy participants are capable of hemodynamically encoding at least four distinct information units on a single-trial level without extensive pretraining and with little effort. Moreover, real-time data analysis based on simple multi-filter correlations allows for automated answer decoding with a high accuracy (94.9%) demonstrating the robustness of the presented method. Following our 'proof of concept', the

  3. Predictive value of brain perfusion SPECT for ketamine response in hyperalgesic fibromyalgia

    Energy Technology Data Exchange (ETDEWEB)

    Guedj, Eric; Cammilleri, Serge; Colavolpe, Cecile; Taieb, David; Laforte, Catherine de; Mundler, Olivier [Centre Hospitalo-Universitaire de la Timone, Service Central de Biophysique et de Medecine Nucleaire, Assistance Publique des Hopitaux de Marseille, Marseille Cedex 5 (France); Niboyet, Jean [Clinique La Phoceanne, Unite d' Etude et de Traitement de la Douleur, Marseille (France)

    2007-08-15

    Ketamine has been used successfully in various proportions of fibromyalgia (FM) patients. However, the response to this specific treatment remains largely unpredictable. We evaluated brain SPECT perfusion before treatment with ketamine, using voxel-based analysis. The objective was to determine the predictive value of brain SPECT for ketamine response. Seventeen women with FM (48 {+-} 11 years; ACR criteria) were enrolled in the study. Brain SPECT was performed before any change was made in therapy in the pain care unit. We considered that a patient was a good responder to ketamine if the VAS score for pain decreased by at least 50% after treatment. A voxel-by-voxel group analysis was performed using SPM2, in comparison to a group of ten healthy women matched for age. The VAS score for pain was 81.8 {+-} 4.2 before ketamine and 31.8 {+-} 27.1 after ketamine. Eleven patients were considered ''good responders'' to ketamine. Responder and non-responder subgroups were similar in terms of pain intensity before ketamine. In comparison to responding patients and healthy subjects, non-responding patients exhibited a significant reduction in bilateral perfusion of the medial frontal gyrus. This cluster of hypoperfusion was highly predictive of non-response to ketamine (positive predictive value 100%, negative predictive value 91%). Brain perfusion SPECT may predict response to ketamine in hyperalgesic FM patients. (orig.)

  4. Event-related brain responses while listening to entire pieces of music

    DEFF Research Database (Denmark)

    Poikonen, Hanna; Alluri, Vinoo; Brattico, Elvira; Lartillot, Olivier; Tervaniemi, Mari; Huotilainen, Minna

    2016-01-01

    Brain responses to discrete short sounds have been studied intensively using the event-related potential (ERP) method, in which the electroencephalogram (EEG) signal is divided into epochs time-locked to stimuli of interest. Here we introduce and apply a novel technique which enables one to isolate...

  5. Predictive value of brain perfusion SPECT for ketamine response in hyperalgesic fibromyalgia

    International Nuclear Information System (INIS)

    Ketamine has been used successfully in various proportions of fibromyalgia (FM) patients. However, the response to this specific treatment remains largely unpredictable. We evaluated brain SPECT perfusion before treatment with ketamine, using voxel-based analysis. The objective was to determine the predictive value of brain SPECT for ketamine response. Seventeen women with FM (48 ± 11 years; ACR criteria) were enrolled in the study. Brain SPECT was performed before any change was made in therapy in the pain care unit. We considered that a patient was a good responder to ketamine if the VAS score for pain decreased by at least 50% after treatment. A voxel-by-voxel group analysis was performed using SPM2, in comparison to a group of ten healthy women matched for age. The VAS score for pain was 81.8 ± 4.2 before ketamine and 31.8 ± 27.1 after ketamine. Eleven patients were considered ''good responders'' to ketamine. Responder and non-responder subgroups were similar in terms of pain intensity before ketamine. In comparison to responding patients and healthy subjects, non-responding patients exhibited a significant reduction in bilateral perfusion of the medial frontal gyrus. This cluster of hypoperfusion was highly predictive of non-response to ketamine (positive predictive value 100%, negative predictive value 91%). Brain perfusion SPECT may predict response to ketamine in hyperalgesic FM patients. (orig.)

  6. USING DIFFERENTIAL REINFORCEMENT TO DECREASE ACADEMIC RESPONSE LATENCIES OF AN ADOLESCENT WITH ACQUIRED BRAIN INJURY

    OpenAIRE

    Heinicke, Megan R; Carr, James E; Mozzoni, Michael P

    2009-01-01

    The present study investigated the effects of contingency-specifying rules and a token economy to decrease the latency to comply with academic instructions by a 16-year-old girl with acquired brain injury. Results showed that treatment was successful in reducing academic response latencies. These results replicate previous research in which differential reinforcement was used to decrease slow responding to academic tasks.

  7. Using Differential Reinforcement to Decrease Academic Response Latencies of an Adolescent with Acquired Brain Injury

    Science.gov (United States)

    Heinicke, Megan R.; Carr, James E.; Mozzoni, Michael P.

    2009-01-01

    The present study investigated the effects of contingency-specifying rules and a token economy to decrease the latency to comply with academic instructions by a 16-year-old girl with acquired brain injury. Results showed that treatment was successful in reducing academic response latencies. These results replicate previous research in which…

  8. Usefulness of hemodynamic sensors for physiologic cardiac pacing in heart failure patients.

    Science.gov (United States)

    Occhetta, Eraldo; Bortnik, Miriam; Marino, Paolo

    2011-01-01

    The rate adaptive sensors applied to cardiac pacing should respond as promptly as the normal sinus node with an highly specific and sensitive detection of the need of increasing heart rate. Sensors operating alone may not provide optimal heart responsiveness: central venous pH sensing, variations in the oxygen content of mixed venous blood, QT interval, breathing rate and pulmonary minute ventilation monitored by thoracic impedance variations, activity sensors. Using sensors that have different attributes but that work in a complementary manners offers distinct advantages. However, complicated sensors interactions may occur. Hemodynamic sensors detect changes in the hemodynamic performances of the heart, which partially depends on the autonomic nervous system-induced inotropic regulation of myocardial fibers. Specific hemodynamic sensors have been designed to measure different expression of the cardiac contraction strength: Peak Endocardial Acceleration (PEA), Closed Loop Stimulation (CLS) and TransValvular Impedance (TVI), guided by intraventricular impedance variations. Rate-responsive pacing is just one of the potential applications of hemodynamic sensors in implantable pacemakers. Other issues discussed in the paper include: hemodynamic monitoring for the optimal programmation and follow up of patients with cardiac resynchronization therapy; hemodynamic deterioration impact of tachyarrhythmias; hemodynamic upper rate limit control; monitoring and prevention of vasovagal malignant syncopes. PMID:21461359

  9. The Acute Inflammatory Response in Trauma / Hemorrhage and Traumatic Brain Injury: Current State and Emerging Prospects

    OpenAIRE

    R, Namas; A, Ghuma; L, Hermus; R, Zamora; DO Okonkwo; TR, Billiar; Y, Vodovotz

    2009-01-01

    Traumatic injury/hemorrhagic shock (T/HS) elicits an acute inflammatory response that may result in death. Inflammation describes a coordinated series of molecular, cellular, tissue, organ, and systemic responses that drive the pathology of various diseases including T/HS and traumatic brain injury (TBI). Inflammation is a finely tuned, dynamic, highly-regulated process that is not inherently detrimental, but rather required for immune surveillance, optimal post-injury tissue repair, and rege...

  10. Differential Brain Response to Alcohol Cue Distractors across Stages of Alcohol Dependence

    OpenAIRE

    Fryer, Susanna L.; Jorgensen, Kasper W.; Yetter, Elizabeth J.; Daurignac, Elsa C.; Watson, Todd D.; Shanbhag, Harshad; Krystal, John H.; Mathalon, Daniel H.

    2012-01-01

    Altered attention to alcohol-related cues is implicated in the craving and relapse cycle characteristic of alcohol dependence (ALC). Prior cue reactivity studies typically invoke explicit attention to alcohol cues, so the neural response underlying incidental cue exposure remains unclear. Here, we embed infrequent, task-irrelevant alcohol and non-alcohol cues in an attention-demanding task, enabling evaluation of brain responses to distracting alcohol cues. Alcohol dependent individuals, acro...

  11. Multisensory stimuli elicit altered oscillatory brain responses at gamma frequencies in patients with schizophrenia

    OpenAIRE

    David B. Stone; Coffman, Brian A; Juan Bustillo; Cheryl Aine

    2014-01-01

    Deficits in auditory and visual unisensory responses are well documented in patients with schizophrenia; however, potential abnormalities elicited from multisensory audio-visual stimuli are less understood. Further, schizophrenia patients have shown abnormal patterns in task-related and task-independent oscillatory brain activity, particularly in the gamma frequency band. We examined oscillatory responses to basic unisensory and multisensory stimuli in schizophrenia patients (N = 46) and heal...

  12. Biphasic modeling of brain tumor biomechanics and response to radiation treatment.

    Science.gov (United States)

    Angeli, Stelios; Stylianopoulos, Triantafyllos

    2016-06-14

    Biomechanical forces are central in tumor progression and response to treatment. This becomes more important in brain cancers where tumors are surrounded by tissues with different mechanical properties. Existing mathematical models ignore direct mechanical interactions of the tumor with the normal brain. Here, we developed a clinically relevant model, which predicts tumor growth accounting directly for mechanical interactions. A three-dimensional model of the gray and white matter and the cerebrospinal fluid was constructed from magnetic resonance images of a normal brain. Subsequently, a biphasic tissue growth theory for an initial tumor seed was employed, incorporating the effects of radiotherapy. Additionally, three different sets of brain tissue properties taken from the literature were used to investigate their effect on tumor growth. Results show the evolution of solid stress and interstitial fluid pressure within the tumor and the normal brain. Heterogeneous distribution of the solid stress exerted on the tumor resulted in a 35% spatial variation in cancer cell proliferation. Interestingly, the model predicted that distant from the tumor, normal tissues still undergo significant deformations while it was found that intratumoral fluid pressure is elevated. Our predictions relate to clinical symptoms of brain cancers and present useful tools for therapy planning. PMID:27086116

  13. Magnetic-stimulation-related physiological artifacts in hemodynamic near-infrared spectroscopy signals.

    Directory of Open Access Journals (Sweden)

    Tiina Näsi

    Full Text Available Hemodynamic responses evoked by transcranial magnetic stimulation (TMS can be measured with near-infrared spectroscopy (NIRS. This study demonstrates that cerebral neuronal activity is not their sole contributor. We compared bilateral NIRS responses following brain stimulation to those from the shoulders evoked by shoulder stimulation and contrasted them with changes in circulatory parameters. The left primary motor cortex of ten subjects was stimulated with 8-s repetitive TMS trains at 0.5, 1, and 2 Hz at an intensity of 75% of the resting motor threshold. Hemoglobin concentration changes were measured with NIRS on the stimulated and contralateral hemispheres. The photoplethysmograph (PPG amplitude and heart rate were recorded as well. The left shoulder of ten other subjects was stimulated with the same protocol while the hemoglobin concentration changes in both shoulders were measured. In addition to PPG amplitude and heart rate, the pulse transit time was recorded. The brain stimulation reduced the total hemoglobin concentration (HbT on the stimulated and contralateral hemispheres. The shoulder stimulation reduced HbT on the stimulated shoulder but increased it contralaterally. The waveforms of the HbT responses on the stimulated hemisphere and shoulder correlated strongly with each other (r = 0.65-0.87. All circulatory parameters were also affected. The results suggest that the TMS-evoked NIRS signal includes components that do not result directly from cerebral neuronal activity. These components arise from local effects of TMS on the vasculature. Also global circulatory effects due to arousal may affect the responses. Thus, studies involving TMS-evoked NIRS responses should be carefully controlled for physiological artifacts and effective artifact removal methods are needed to draw inferences about TMS-evoked brain activity.

  14. Investigation of neural correlates between perception of pain and hemodynamic response measured in the pre-frontal cortex using functional near infra-red spectroscopy

    Science.gov (United States)

    Krishnamurthy, Venkatagiri

    Perception of pain is multi-dimensional, comprising three major psychological dimensions: sensory-discriminative, motivational-affective and cognitive-evaluative. This dissertation study investigates the cognitive evaluation of pain, by acquiring functional Near Infra-Red Spectroscopic (fNIRS) measurements from the prefrontal cortex (PFC) areas, during mechanical and thermal pain stimulation induced on the subject's volar forearm. Clustered-wise analysis on the oxy-hemoglobin (HbO) response from specific PFC areas was followed by categorizing the resulting HbO response into early (0.1--12sec) and late (12.1--25sec) phases. For each respective phase, regression analysis was carried between the HbO-derived parameters and behaviorally measured pain rating. The major findings of this study include: (1) across both 41°C and 48°C thermal stimulation, significant DeltaHbO deactivation was observed during the late phase, in the left hemispheric (LH) anterior PFC (aPFC) or Brodmann area 10 (BA 10). (2) Significant correlates of pain rating were observed in the LH prefrontal areas: (a) under mechanical stimulation, early phase HbO-derived peak intensity (PI) from LH aPFC correlated with the pain rating. (b) Under both 41°C and 48°C thermal stimulation, late phase HbO-derived PI from the LH dorsolateral PFC (DLPFC or BA 46) showed correlation with the pain rating. (3) The significant correlates observed from the right hemispheric (RH) PFC were: (a) under mechanical stimulation, early phase HbO-derived FWHM from the RH aPFC correlated with the pain rating. (b) Under 41°C thermal stimulation, late phase HbO-derived PI from the RH DLPFC area correlated with the pain rating. (4) The late phase HbO-derived time to peak from LH aPFC reflected cognitive discrimination of two different pain levels (41°C and 48°C). The observed trend for DeltaHbO activation and deactivation could possibly be due to synaptic-induced vasodilation and vasoconstriction leading to increased or

  15. Affective responses after different intensities of exercise in patients with traumatic brain injury

    OpenAIRE

    Rzezak, Patricia; Caxa, Luciana; Santolia, Patricia; Hanna K.M. Antunes; Suriano, Italo; Tufik, Sérgio; de Mello, Marco T.

    2015-01-01

    Background: Patients with traumatic brain injury (TBI) usually have mood and anxiety symptoms secondary to their brain injury. Exercise may be a cost-effective intervention for the regulation of the affective responses of this population. However, there are no studies evaluating the effects of exercise or the optimal intensity of exercise for this clinical group. Methods: Twelve male patients with moderate or severe TBI [mean age of 31.83 and SD of 9.53] and 12 age- and gender-matched heal...

  16. Acute pharmacologically induced shifts in serotonin availability abolish emotion-selective responses to negative face emotions in distinct brain networks

    DEFF Research Database (Denmark)

    Grady, Cheryl Lynn; Siebner, Hartwig R; Hornboll, Bettina;

    2013-01-01

    Pharmacological manipulation of serotonin availability can alter the processing of facial expressions of emotion. Using a within-subject design, we measured the effect of serotonin on the brain's response to aversive face emotions with functional MRI while 20 participants judged the gender...... distributed brain responses identified two brain networks with modulations of activity related to face emotion and serotonin level. The first network included the left amygdala, bilateral striatum, and fusiform gyri. During the Control session this network responded only to fearful faces; increasing serotonin...... is critical for maintaining a differentiated brain response to threatening face emotions. Lower serotonin leads to a broadening of a normally fear-specific response to anger, and higher levels reduce the differentiated brain response to aversive face emotions....

  17. Effect of three different dosages of magnesium sulfate on attenuating hemodynamic responses after electroconvulsive therapy: a randomized, double-blind, placebo-controlled trial

    International Nuclear Information System (INIS)

    Objective: The purpose of this randomized, double-blind, placebo-controlled crossover study was to compare the efficacy of three different dosages of MgSO/sub 4/ administration (10, 20, and 30 mg/kg) versus placebo on attenuation of cardiovascular response to electroconvulsive therapy (ECT). Methodology: Thirty-five adult patients scheduled for 8 ECT sessions were randomly assigned to be allocated twice into one of the four study groups: MgSO/sub 4/ 10 mg/kg (M10), MgSO/sub 4/ 20 mg/ kg (M20), MgSO/sub 4/ 30 mg/kg (M30), and placebo control (P). Systolic (SAP), diastolic (DAP) and mean arterial pressure (MAP) and heart rate (HR) were recorded at 0, 1, 3, and 10 minutes after termination of ECT-induced seizures. Duration of electroencephalographs (EEGs) and motor seizures and peak HR during convulsions were also recorded. Results: Changes in SAP, DAP, and MAP were significantly attenuated at 0, one, and three minutes after ECT in groups M20 and M30 compared with group P (P< 0.05). Peak HR changes were significantly less in groups M20 and M30 compared with groups M10 and P (P< 0.05). Duration of motor and EEG seizure activity was not significantly different among the four groups. Conclusion: Administration of either 20 or 30 mg/kg MgSO/sub 4/ significantly attenuated increased blood pressure and peak HR after ECT without decreasing seizure duration. (author)

  18. Computer Controlled Switching Device for Deep Brain Stimulation

    Directory of Open Access Journals (Sweden)

    J. Tauchmanová

    2007-01-01

    Full Text Available This paper has two goals. The practical part deals with the design of a computer controlled switching device for an external stimulator for deep brain stimulation. The switching device is used during investigations with functional magnetic resonance for controlling signals leading to the deep brain stimulation (DBS electrode in the patient's brain. The motivation for designing this device was improve measured data quality and to enable new types of experiments.The theoretical part reports on early attempts to approach the problem of modeling and localizing the neural response of the human brain as a system identification and estimation task. The parametric identification method and real fMRI data are used for modeling the hemodynamic response.The project is in cooperation with 1st Faculty of Medicine, Charles University in Prague and Na Homolce hospital in Prague.

  19. Influence of paravertebrals miorelaxation on cerebral hemodynamics of sportsmen

    Directory of Open Access Journals (Sweden)

    Syshko D.V.

    2014-01-01

    Full Text Available Purpose: Paravertebrals miorelaxation was the complex of exercises in a water environment directed on the decline of tone of paravertebral muscles. Material: Before and after it was used of paravertebrals miorelaxation registered the indexes of reoentsefalografics at the sportsmen engaged in the Greek-Roman fight (n=22 by football (n=24 and heavy athletics (n=25. Results : The changes, that have been determined at the wrestlers, was in the form of increasing tone of large (increase TRF, TGRР, decreased ADR and medium (decreased Т1, Т2 arteries of the brain, decreased tone of the small arteries. Paravertebral myorelaxation of weightlifters caused them changes in the form of increasing tone of the great vessels (increase Т3, decreased tone of large and medium-sized arteries of the brain (increase АDR, Т2, increasing the tone of the small arteries (increase АI, DI. Reliable changes in cerebral hemodynamics have not been established at football players. Conclusions: The obtained data indicate that there are different mechanisms of adaptation in the brain blood vessels under conditions of the paravertebral miorelaxation. These differences are predetermined by two main factors: the functional state of the cardiovascular system in general and the functional states of the system of regulation of cerebral hemodynamics.

  20. Gender Differences in Human Single Neuron Responses to Male Emotional Faces

    OpenAIRE

    Morgan eNewhoff; Treiman, David M.; Smith, Kris A.; Steinmetz, Peter N.

    2015-01-01

    Well-documented differences in the psychology and behavior of men and women have spurred extensive exploration of gender's role within the brain, particularly regarding emotional processing. While neuroanatomical studies clearly show differences between the sexes, the functional effects of these differences are less understood. Neuroimaging studies have shown inconsistent locations and magnitudes of gender differences in brain hemodynamic responses to emotion. To better understand the neuroph...

  1. Gender differences in human single neuron responses to male emotional faces

    OpenAIRE

    Newhoff, Morgan; Treiman, David M.; Smith, Kris A.; Steinmetz, Peter N.

    2015-01-01

    Well-documented differences in the psychology and behavior of men and women have spurred extensive exploration of gender's role within the brain, particularly regarding emotional processing. While neuroanatomical studies clearly show differences between the sexes, the functional effects of these differences are less understood. Neuroimaging studies have shown inconsistent locations and magnitudes of gender differences in brain hemodynamic responses to emotion. To better understand the neuroph...

  2. Elevated pulmonary artery pressure and brain natriuretic peptide in high altitude pulmonary edema susceptible non-mountaineers

    OpenAIRE

    Rajinder K. Gupta; Himashree, G.; Krishan Singh; Poonam Soree; Koundinya Desiraju; Anurag Agrawal; Dishari Ghosh; Deepak Dass; Prassana K. Reddy; Usha Panjwani; Shashi Bala Singh

    2016-01-01

    Exaggerated pulmonary pressor response to hypoxia is a pathgonomic feature observed in high altitude pulmonary edema (HAPE) susceptible mountaineers. It was investigated whether measurement of basal pulmonary artery pressure (Ppa) and brain natriuretic peptide (BNP) could improve identification of HAPE susceptible subjects in a non-mountaineer population. We studied BNP levels, baseline hemodynamics and the response to hypoxia (FIo2 = 0.12 for 30 min duration at sea level) in 11 HAPE resistan...

  3. Responsiveness of fetal rat brain cells to glia maturation factor during neoplastic transformation in cell culture

    DEFF Research Database (Denmark)

    Haugen, A; Laerum, O D; Bock, E

    1981-01-01

    The effect of partially purified extracts from adult pig brains containing a glia maturation protein factor (BE) has been investigated on neural cells during carcinogenesis. Pregnant BD IX-rats were given a single transplacental dose of the carcinogen ethylnitrosourea (EtNU) on the 18th day of...... gestation. The brains of the treated fetuses were transferred to cell culture and underwent neoplastic transformation with a characteristic sequence of phenotypic alterations which could be divided into five different stages. During the first 40 days after explantation (stage I & II) BE induced...... appreciable effect on GFA-content was seen any longer, although some few weakly GFA positive cells could be observed in all permanent cell lines. Fetal rat brain cells therefore seem to become less responsive to this differentiation inducer during neoplastic transformation in cell culture....

  4. Effect of oculomotor rehabilitation on accommodative responsivity in mild traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Preethi Thiagarajan, BS Optom, MS, PhD

    2014-03-01

    Full Text Available Accommodative dysfunction is a common oculomotor sequelae of mild traumatic brain injury (mTBI. This study evaluated a range of dynamic (objective and static (subjective measures of accommodation in 12 nonstrabismic individuals with mTBI and near vision-related symptoms before and after oculomotor training (OMT and placebo (P training (6 wk, two sessions per week, 3 h of training each. Following OMT, the dynamics of accommodation improved markedly. Clinically, there was a significant increase in the maximum accommodative amplitude both monocularly and binocularly. In addition, the near vision symptoms reduced along with improved visual attention. None of the measures were found to change significantly following P training. These results provide evidence for a significant positive effect of the accommodatively based OMT on accommodative responsivity. Such improvement is suggestive of oculomotor learning, demonstrating considerable residual brain-visual system plasticity in the adult compromised brain.

  5. Brain Connectivity Dissociates Responsiveness from Drug Exposure during Propofol-Induced Transitions of Consciousness.

    Science.gov (United States)

    Chennu, Srivas; O'Connor, Stuart; Adapa, Ram; Menon, David K; Bekinschtein, Tristan A

    2016-01-01

    Accurately measuring the neural correlates of consciousness is a grand challenge for neuroscience. Despite theoretical advances, developing reliable brain measures to track the loss of reportable consciousness during sedation is hampered by significant individual variability in susceptibility to anaesthetics. We addressed this challenge using high-density electroencephalography to characterise changes in brain networks during propofol sedation. Assessments of spectral connectivity networks before, during and after sedation were combined with measurements of behavioural responsiveness and drug concentrations in blood. Strikingly, we found that participants who had weaker alpha band networks at baseline were more likely to become unresponsive during sedation, despite registering similar levels of drug in blood. In contrast, phase-amplitude coupling between slow and alpha oscillations correlated with drug concentrations in blood. Our findings highlight novel markers that prognosticate individual differences in susceptibility to propofol and track drug exposure. These advances could inform accurate drug titration and brain state monitoring during anaesthesia. PMID:26764466

  6. Speeded Near Infrared Spectroscopy (NIRS) Response Detection

    OpenAIRE

    Cui, Xu; Bray, Signe; Reiss, Allan L

    2010-01-01

    The hemodynamic response measured by Near Infrared Spectroscopy (NIRS) is temporally delayed from the onset of the underlying neural activity. As a consequence, NIRS based brain-computer-interfaces (BCIs) and neurofeedback learning systems, may have a latency of several seconds in responding to a change in participants' behavioral or mental states, severely limiting the practical use of such systems. To explore the possibility of reducing this delay, we used a multivariate pattern classificat...

  7. Untangling the Effect of Head Acceleration on Brain Responses to Blast Waves.

    Science.gov (United States)

    Mao, Haojie; Unnikrishnan, Ginu; Rakesh, Vineet; Reifman, Jaques

    2015-12-01

    Multiple injury-causing mechanisms, such as wave propagation, skull flexure, cavitation, and head acceleration, have been proposed to explain blast-induced traumatic brain injury (bTBI). An accurate, quantitative description of the individual contribution of each of these mechanisms may be necessary to develop preventive strategies against bTBI. However, to date, despite numerous experimental and computational studies of bTBI, this question remains elusive. In this study, using a two-dimensional (2D) rat head model, we quantified the contribution of head acceleration to the biomechanical response of brain tissues when exposed to blast waves in a shock tube. We compared brain pressure at the coup, middle, and contre-coup regions between a 2D rat head model capable of simulating all mechanisms (i.e., the all-effects model) and an acceleration-only model. From our simulations, we determined that head acceleration contributed 36-45% of the maximum brain pressure at the coup region, had a negligible effect on the pressure at the middle region, and was responsible for the low pressure at the contre-coup region. Our findings also demonstrate that the current practice of measuring rat brain pressures close to the center of the brain would record only two-thirds of the maximum pressure observed at the coup region. Therefore, to accurately capture the effects of acceleration in experiments, we recommend placing a pressure sensor near the coup region, especially when investigating the acceleration mechanism using different experimental setups. PMID:26458125

  8. Response of rat brain protein synthesis to ethanol and sodium barbital

    International Nuclear Information System (INIS)

    Central nervous system (CNS) depressants such as ethanol and barbiturates under acute or chronic conditions can induce changes in rat brain protein synthesis. While these data demonstrate the individual effects of drugs on protein synthesis, the response of brain protein synthesis to alcohol-drug interactions is not known. The goal of the present study was to determine the individual and combined effects of ethanol and sodium barbital on brain protein synthesis and gain an understanding of the mechanisms by which these alterations in protein synthesis are produced. Specifically, the in vivo and in vitro effects of sodium barbital (one class of barbiturates which is not metabolized by the hepatic tissue) were examined on brain protein synthesis in rats made physically dependent upon ethanol. Using cell free brain polysomal systems isolated from Control, Ethanol and 24 h Ethanol Withdrawn rats, data show that sodium barbital, when intubated intragastrically, inhibited the time dependent incorporation of 14C) leucine into protein by all three groups of ribosomes. Under these conditions, the Ethanol Withdrawn group displayed the largest inhibition of the 14C) leucine incorporation into protein when compared to the Control and Ethanol groups. In addition, sodium barbital when added at various concentrations in vitro to the incubation medium inhibited the incorporation of 14C) leucine into protein by Control and Ethanol polysomes. The inhibitory effects were also obtained following preincubation of ribosomes in the presence of barbital but not cycloheximide. Data suggest that brain protein synthesis, specifically brain polysomes, through interaction with ethanol or barbital are involved in the functional development of tolerance. These interactions may occur through proteins or polypeptide chains or alterations in messenger RNA components associated with the ribosomal units

  9. Brain Fingerprinting

    Directory of Open Access Journals (Sweden)

    ravi kumar

    2012-12-01

    Full Text Available Brain Fingerprinting is a scientific technique to determine whether or not specific information is stored in an individual's brain by measuring a electrical brain wave response to Word, phrases, or picture that are presented on computer screen. Brain Fingerprinting is a controversial forensic science technique that uses electroencephalograph y (EEG to determine whether specific information is stored in a subject's brain

  10. Diet-Induced Weight Loss Alters Functional Brain Responses during an Episodic Memory Task

    Directory of Open Access Journals (Sweden)

    Carl-Johan Boraxbekk

    2015-07-01

    Full Text Available Objective: It has been suggested that overweight is negatively associated with cognitive functions. The aim of this study was to investigate whether a reduction in body weight by dietary interventions could improve episodic memory performance and alter associated functional brain responses in overweight and obese women. Methods: 20 overweight postmenopausal women were randomized to either a modified paleolithic diet or a standard diet adhering to the Nordic Nutrition Recommendations for 6 months. We used functional magnetic resonance imaging to examine brain function during an episodic memory task as well as anthropometric and biochemical data before and after the interventions. Results: Episodic memory performance improved significantly (p = 0.010 after the dietary interventions. Concomitantly, brain activity increased in the anterior part of the right hippocampus during memory encoding, without differences between diets. This was associated with decreased levels of plasma free fatty acids (FFA. Brain activity increased in pre-frontal cortex and superior/middle temporal gyri. The magnitude of increase correlated with waist circumference reduction. During episodic retrieval, brain activity decreased in inferior and middle frontal gyri, and increased in middle/superior temporal gyri. Conclusions: Diet-induced weight loss, associated with decreased levels of plasma FFA, improves episodic memory linked to increased hippocampal activity.

  11. Mitochondrial responses to prolonged anoxia in brain of red-eared slider turtles.

    Science.gov (United States)

    Pamenter, Matthew E; Gomez, Crisostomo R; Richards, Jeffrey G; Milsom, William K

    2016-01-01

    Mitochondria are central to aerobic energy production and play a key role in neuronal signalling. During anoxia, however, the mitochondria of most vertebrates initiate deleterious cell death cascades. Nonetheless, a handful of vertebrate species, including some freshwater turtles, are remarkably tolerant of low oxygen environments and survive months of anoxia without apparent damage to brain tissue. This tolerance suggests that mitochondria in the brains of such species are adapted to withstand prolonged anoxia, but little is known about potential neuroprotective responses. In this study, we address such mechanisms by comparing mitochondrial function between brain tissues isolated from cold-acclimated red-eared slider turtles (Trachemys scripta elegans) exposed to two weeks of either normoxia or anoxia. We found that brain mitochondria from anoxia-acclimated turtles exhibited a unique phenotype of remodelling relative to normoxic controls, including: (i) decreased citrate synthase and F1FO-ATPase activity but maintained protein content, (ii) markedly reduced aerobic capacity, and (iii) mild uncoupling of the mitochondrial proton gradient. These data suggest that turtle brain mitochondria respond to low oxygen stress with a unique suite of changes tailored towards neuroprotection. PMID:26763217

  12. Brain responses in 4-month-old infants are already language specific.

    Science.gov (United States)

    Friederici, Angela D; Friedrich, Manuela; Christophe, Anne

    2007-07-17

    Language is the most important faculty that distinguishes humans from other animals. Infants learn their native language fast and effortlessly during the first years of life, as a function of the linguistic input in their environment. Behavioral studies reported the discrimination of melodic contours [1] and stress patterns [2, 3] in 1-4-month-olds. Behavioral [4, 5] and brain measures [6-8] have shown language-independent discrimination of phonetic contrasts at that age. Language-specific discrimination, however, has been reported for phonetic contrasts only for 6-12-month-olds [9-12]. Here we demonstrate language-specific discrimination of stress patterns in 4-month-old German and French infants by using electrophysiological brain measures. We compare the processing of disyllabic words differing in their rhythmic structure, mimicking German words being stressed on the first syllable, e.g., pápa/daddy[13], and French ones being stressed on the second syllable, e.g., papá/daddy. Event-related brain potentials reveal that experience with German and French differentially affects the brain responses of 4-month-old infants, with each language group displaying a processing advantage for the rhythmic structure typical in its native language. These data indicate language-specific neural representations of word forms in the infant brain as early as 4 months of age. PMID:17583508

  13. Brain response to photodynamic therapy and Photofrin, nonsulfonated aluminum phthalocyanine and tin purpurin

    Science.gov (United States)

    Dereski, Mary O.; Madigan, Lara; Chopp, Michael

    1995-03-01

    Photodynamic therapy (PDT) with PhotofrinR, nonsulfonated aluminum phthalocyanine (AlClPc), and tin ethyl etiopurpurin I (SnET2) was investigated on normal and tumored (9L gliosarcoma) rat brain. Rats were injected 48 h prior to PDT (3 - 280 J/cm2, 100 mW/cm2) with PhotofrinR (12.5 mg/kg) and AlClPc (2.0 mg/kg) and 24 h prior with SnET2 (1.0 mg/kg). Substantial lesions were present in normal brain with PhotofrinR and with AlClPc at all energy levels. No lesions were present with SnET2. Tumor response for PhotofrinR and AlClPc did not occur with doses less than 140 J/cm2. Drug concentrations for tumored/contralateral hemisphere for PhotofrinR and AlClPc were 1.86 and 7.86, respectively. These data indicate: (1) normal brain is more sensitive than the tumored brain with PhotofrinR and AlClPc, and (2) normal brain sensitivity to SnET2 is less than that with PhotofrinR and AlClPc.

  14. Methodology to assess response to stereotactic irradiation in lesions of the brain stem

    International Nuclear Information System (INIS)

    Purpose/Objective: Magnetic resonance image changes were measured at various time points after patients were treated with stereotactic irradiation to brain lesions in and around the brain stem. Results were correlated with the dose of ionizing radiation given to the same anatomical region. The methodology was developed to assess its utility in predicting brain stem injury and lesion response to high-dose, single-fraction radiation treatments. Materials and Methods: We developed a computerized system for spatially correlating and analyzing changes in T1 weighted, gadolinium enhanced, 3-D magnetic resonance (MR) image sets at multiple time points after treatment with stereotactic brain irradiation. Using this system, we were able to compare post-treatment with pre-treatment images used for computerized treatment planning. The treatment planning image sets contained the dose-volume information for each treatment. The measured quantities included pixel value, size of enhanced region, and dose point value. Twelve patients, having a minimum follow-up after radiosurgery of 6 months and brain lesions of various types, were selected for review: 1 glioma, 4 juvenile pilocytic astrocytomas, 1 cavernous hemangioma, 1 ependymoma, 1 primitive neuroectodermal tumor, 1 meningioma, and 3 metastases. Patient ages ranged from 3 to 59 years at time of treatment. The prescription doses to the lesions ranged from 12 to 20 Gy. The severity and duration of complications were noted for each. Results: Image intensity changes were measured and correlated with dose on a pixel-by-pixel basis in order to plot the time course of the changes. The estimate of spatial accuracy for locating the dose and voxel of tissue was within 2 mm. The sequelae of radiologic changes to irradiation were mixed. We observed increases as well as decreases in the density of the irradiated region with time after treatment which depended on the patient. One patient had nearly complete disappearance of the enhancing

  15. Hemodynamic Assessment and Monitoring in the Intensive Care Unit: an Overview

    OpenAIRE

    Adler, Adam C.; Ramakant Sharma; Thomas Higgins; McGee, William T

    2014-01-01

    The goal of hemodynamic monitoring in intensive care is to assess the adequacy of perfusion, specifically with regard to maintaining sufficient perfusion pressures and oxygen delivery. Precise volume management of peri-operative and critical care patients is crucial as under or over resuscitation is associated with adverse outcomes. Hemodynamic monitoring allows care to be individualized based on specific patient response to therapy and can provide early warning of impending perfusion deficit...

  16. Bench-to-bedside review: An approach to hemodynamic monitoring - Guyton at the bedside

    OpenAIRE

    Magder, Sheldon

    2012-01-01

    Hemodynamic monitoring is used to identify deviations from hemodynamic goals and to assess responses to therapy. To accomplish these goals one must understand how the circulation is regulated. In this review I begin with an historical review of the work of Arthur Guyton and his conceptual understanding of the circulation and then present an approach by which Guyton's concepts can be applied at the bedside. Guyton argued that cardiac output and central venous pressure are determined by the int...

  17. Non-invasive optical measurement of cerebral metabolism and hemodynamics in infants.

    Science.gov (United States)

    Lin, Pei-Yi; Roche-Labarbe, Nadege; Dehaes, Mathieu; Carp, Stefan; Fenoglio, Angela; Barbieri, Beniamino; Hagan, Katherine; Grant, P Ellen; Franceschini, Maria Angela

    2013-01-01

    Perinatal brain injury remains a significant cause of infant mortality and morbidity, but there is not yet an effective bedside tool that can accurately screen for brain injury, monitor injury evolution, or assess response to therapy. The energy used by neurons is derived largely from tissue oxidative metabolism, and neural hyperactivity and cell death are reflected by corresponding changes in cerebral oxygen metabolism (CMRO₂). Thus, measures of CMRO₂ are reflective of neuronal viability and provide critical diagnostic information, making CMRO₂ an ideal target for bedside measurement of brain health. Brain-imaging techniques such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT) yield measures of cerebral glucose and oxygen metabolism, but these techniques require the administration of radionucleotides, so they are used in only the most acute cases. Continuous-wave near-infrared spectroscopy (CWNIRS) provides non-invasive and non-ionizing radiation measures of hemoglobin oxygen saturation (SO₂) as a surrogate for cerebral oxygen consumption. However, SO₂ is less than ideal as a surrogate for cerebral oxygen metabolism as it is influenced by both oxygen delivery and consumption. Furthermore, measurements of SO₂ are not sensitive enough to detect brain injury hours after the insult, because oxygen consumption and delivery reach equilibrium after acute transients. We investigated the possibility of using more sophisticated NIRS optical methods to quantify cerebral oxygen metabolism at the bedside in healthy and brain-injured newborns. More specifically, we combined the frequency-domain NIRS (FDNIRS) measure of SO2 with the diffuse correlation spectroscopy (DCS) measure of blood flow index (CBFi) to yield an index of CMRO₂ (CMRO₂i). With the combined FDNIRS/DCS system we are able to quantify cerebral metabolism and hemodynamics. This represents an improvement over CWNIRS for detecting brain health, brain

  18. Vestibular stimulation leads to distinct hemodynamic patterning

    Science.gov (United States)

    Kerman, I. A.; Emanuel, B. A.; Yates, B. J.

    2000-01-01

    Previous studies demonstrated that responses of a particular sympathetic nerve to vestibular stimulation depend on the type of tissue the nerve innervates as well as its anatomic location. In the present study, we sought to determine whether such precise patterning of vestibulosympathetic reflexes could lead to specific hemodynamic alterations in response to vestibular afferent activation. We simultaneously measured changes in systemic blood pressure and blood flow (with the use of Doppler flowmetry) to the hindlimb (femoral artery), forelimb (brachial artery), and kidney (renal artery) in chloralose-urethane-anesthetized, baroreceptor-denervated cats. Electrical vestibular stimulation led to depressor responses, 8 +/- 2 mmHg (mean +/- SE) in magnitude, that were accompanied by decreases in femoral vasoconstriction (23 +/- 4% decrease in vascular resistance or 36 +/- 7% increase in vascular conductance) and increases in brachial vascular tone (resistance increase of 10 +/- 6% and conductance decrease of 11 +/- 4%). Relatively small changes (vasoconstriction in all three beds. These data suggest that vestibular inputs lead to a complex pattern of cardiovascular changes that is distinct from that which occurs in response to activation of other types of somatic afferents.

  19. Cannabinoid Signaling and Neuroinflammatory Diseases: A Melting pot for the Regulation of Brain Immune Responses.

    Science.gov (United States)

    Chiurchiù, Valerio; Leuti, Alessandro; Maccarrone, Mauro

    2015-06-01

    The concept of the central nervous system (CNS) as an immune-privileged site, essentially due to the presence of the blood brain barrier, appears to be overly simplistic. Indeed, within healthy CNS immune activities are permitted and are required for neuronal function and host defense, not only due to the presence of the resident innate immune cells of the brain, but also by virtue of a complex cross-talk of the CNS with peripheral immune cells. Nonetheless, long-standing and persisting neuroinflammatory responses are most often detrimental and characterize several neuroinflammatory diseases, including multiple sclerosis, Alzheimer's disease and amyotrophic lateral sclerosis. A growing body of evidence suggests that Cannabis sativa-derived phytocannabinoids, as well as synthetic cannabinoids, are endowed with significant immunoregulatory and anti-inflammatory properties, both in peripheral tissues and in the CNS, through the activation of cannabinoid receptors. In this review, the immunomodulatory effects of cannabinoid signaling on the most relevant brain immune cells will be discussed. In addition, the impact of cannabinoid regulation on the overall integration of the manifold brain immune responses will also be highlighted, along with the implication of these compounds as potential agents for the management of neuroinflammatory disorders. PMID:25601726

  20. Principal component analysis of the cytokine and chemokine response to human traumatic brain injury.

    Directory of Open Access Journals (Sweden)

    Adel Helmy

    Full Text Available There is a growing realisation that neuro-inflammation plays a fundamental role in the pathology of Traumatic Brain Injury (TBI. This has led to the search for biomarkers that reflect these underlying inflammatory processes using techniques such as cerebral microdialysis. The interpretation of such biomarker data has been limited by the statistical methods used. When analysing data of this sort the multiple putative interactions between mediators need to be considered as well as the timing of production and high degree of statistical co-variance in levels of these mediators. Here we present a cytokine and chemokine dataset from human brain following human traumatic brain injury and use principal component analysis and partial least squares discriminant analysis to demonstrate the pattern of production following TBI, distinct phases of the humoral inflammatory response and the differing patterns of response in brain and in peripheral blood. This technique has the added advantage of making no assumptions about the Relative Recovery (RR of microdialysis derived parameters. Taken together these techniques can be used in complex microdialysis datasets to summarise the data succinctly and generate hypotheses for future study.

  1. Hemodynamic versus adrenergic control of cat right ventricular hypertrophy.

    OpenAIRE

    Cooper, G.; Kent, R.L.; Uboh, C.E.; Thompson, E W; Marino, T A

    1985-01-01

    The purpose of this study was to determine whether cardiac hypertrophy in response to hemodynamic overloading is a primary result of the increased load or is instead a secondary result of such other factors as concurrent sympathetic activation. To make this distinction, four experiments were done; the major experimental result, cardiac hypertrophy, was assessed in terms of ventricular mass and cardiocyte cross-sectional area. In the first experiment, the cat right ventricle was loaded differe...

  2. Flexible multivariate hemodynamics fMRI data analyses and simulations with PyHRF

    Directory of Open Access Journals (Sweden)

    Thomas eVincent

    2014-04-01

    Full Text Available As part of fMRI data analysis, the pyhrf package provides a set of tools for addressing the two main issues involved in intra-subject fMRI data analysis: (i the localization of cerebral regions that elicit evoked activity and (ii the estimation of activation dynamics also known as Hemodynamic Response Function (HRF recovery. To tackle these two problems, pyhrf implements the Joint Detection-Estimation framework~(JDE which recovers parcel-level HRFs and embeds an adaptive spatio-temporal regularization scheme of activation maps. With respect to the sole detection issue~(i, the classical voxelwise GLM procedure is also available through nipy, whereas Finite Impulse Response~(FIR and temporally regularized FIR models are concerned with HRF estimation~(ii and are specifically implemented in pyhrf. Several parcellation tools are also integrated such as spatial and functional clustering. Parcellations may be used for spatial averaging prior to FIR/RFIR analysis or to specify the spatial support of the HRF estimates in the JDE approach. These analysis procedures can be applied either to volumic data sets or to data projected onto the cortical surface. For validation purpose, this package is shipped with artificial and real fMRI data sets, which are used in this paper to compare the outcome of the different available approaches. The artificial fMRI data generator is also described to illustrate how to simulate different activation configurations, HRF shapes or nuisance components. To cope with the high computational needs for inference, pyhrf handles distributing computing by exploiting cluster units as well as multi-core machines. Finally, a dedicated viewer is presented, which handles $n$-dimensional images and provides suitable features to explore whole brain hemodynamics~(time series, maps, ROI mask overlay.

  3. Insula and inferior frontal triangularis activations distinguish between conditioned brain responses using emotional sounds for basic BCI communication

    OpenAIRE

    van der Heiden, Linda; Liberati, Giulia; Sitaram, Ranganatha; Kim, Sunjung; Jaśkowski, Piotr; Raffone, Antonino; Olivetti Belardinelli, Marta; Birbaumer, Niels; Veit, Ralf

    2014-01-01

    In order to enable communication through a brain-computer interface (BCI), it is necessary to discriminate between distinct brain responses. As a first step, we probed the possibility to discriminate between affirmative (“yes”) and negative (“no”) responses using a semantic classical conditioning paradigm, within an fMRI setting. Subjects were presented with congruent and incongruent word-pairs as conditioned stimuli (CS), respectively eliciting affirmative and negative responses. Incongruent...

  4. Non-invasive measurements of tissue hemodynamics with hybrid diffuse optical methods

    Science.gov (United States)

    Durduran, Turgut

    Diffuse optical techniques were used to measure hemodynamics of tissues non-invasively. Spectroscopy and tomography of the brain, muscle and implanted tumors were carried out in animal models and humans. Two qualitatively different methods, diffuse optical tomography and diffuse correlation tomography, were hybridized permitting simultaneous measurement of total hemoglobin concentration, blood oxygen saturation and blood flow. This combination of information was processed further to derive estimates of oxygen metabolism (e.g. CMRO 2) in tissue. The diffuse correlation measurements of blood flow were demonstrated in human tissues, for the first time, demonstrating continous, non-invasive imaging of oxygen metabolism in large tissue volumes several centimeters below the tissue surface. The bulk of these investigations focussed on cerebral hemodynamics. Extensive validation of this methodology was carried out in in vivo rat brain models. Three dimensional images of deep tissue hemodynamics in middle cerebral artery occlusion and cortical spreading depression (CSD) were obtained. CSD hemodynamics were found to depend strongly on partial pressure of carbon dioxide. The technique was then adapted for measurement of human brain. All optical spectroscopic measurements of CMRO2 during functional activation were obtained through intact human skull non-invasively. Finally, a high spatio-temporal resolution measurement of cerebral blood flow due to somatosensory cortex activation following electrical forepaw stimulation in rats was carried out with laser speckle flowmetry. New analysis methods were introduced for laser speckle flowmetry. In other organs, deep tissue hemodynamics were measured on human calf muscle during exercise and cuff-ischemia and were shown to have some clinical utility for peripheral vascular disease. In mice tumor models, the measured hemodynamics were shown to be predictive of photodynamic therapy efficacy, again suggesting promise of clinical utility

  5. Effect of oculomotor rehabilitation on vergence responsivity in mild traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Preethi Thiagarajan, BS Optom, MS, PhD

    2013-12-01

    Full Text Available A range of dynamic and static vergence responses were evaluated in 12 individuals with mild traumatic brain injury (age: 29 +/– 3 yr having near vision symptoms. All measures were performed in a crossover design before and after oculomotor training (OMT and placebo (P training. Following OMT, peak velocity for both convergence and divergence increased significantly. Increased peak velocity was significantly correlated with increased clinically based vergence prism flipper rate. Steady-state response variability for convergence reduced significantly following OMT. The maximum amplitude of convergence, relative fusional amplitudes, and near stereoacuity improved significantly. In addition, symptoms reduced significantly, and visual attention improved markedly. None of the measures were found to change significantly following P training. The significant improvement in most aspects of vergence eye movements following OMT demonstrates considerable residual brain plasticity via oculomotor learning. The improved vergence affected positively on nearwork-related symptoms and visual attention.

  6. DeltaFosB in brain reward circuits mediates resilience to stress and antidepressant responses.

    Science.gov (United States)

    Vialou, Vincent; Robison, Alfred J; Laplant, Quincey C; Covington, Herbert E; Dietz, David M; Ohnishi, Yoshinori N; Mouzon, Ezekiell; Rush, Augustus J; Watts, Emily L; Wallace, Deanna L; Iñiguez, Sergio D; Ohnishi, Yoko H; Steiner, Michel A; Warren, Brandon L; Krishnan, Vaishnav; Bolaños, Carlos A; Neve, Rachael L; Ghose, Subroto; Berton, Olivier; Tamminga, Carol A; Nestler, Eric J

    2010-06-01

    In contrast with the many studies of stress effects on the brain, relatively little is known about the molecular mechanisms of resilience, the ability of some individuals to escape the deleterious effects of stress. We found that the transcription factor DeltaFosB mediates an essential mechanism of resilience in mice. Induction of DeltaFosB in the nucleus accumbens, an important brain reward-associated region, in response to chronic social defeat stress was both necessary and sufficient for resilience. DeltaFosB induction was also required for the standard antidepressant fluoxetine to reverse behavioral pathology induced by social defeat. DeltaFosB produced these effects through induction of the GluR2 AMPA glutamate receptor subunit, which decreased the responsiveness of nucleus accumbens neurons to glutamate, and through other synaptic proteins. Together, these findings establish a previously unknown molecular pathway underlying both resilience and antidepressant action. PMID:20473292

  7. Carcinoma cells misuse the host tissue damage response to invade the brain

    OpenAIRE

    Chuang, Han-Ning; van Rossum, Denise; Sieger, Dirk; Siam, Laila; Klemm, Florian; Bleckmann, Annalen; Bayerlová, Michaela; Farhat, Katja; Scheffel, Jörg; Schulz, Matthias; Dehghani, Faramarz; Stadelmann, Christine; Hanisch, Uwe-Karsten; Binder, Claudia; Pukrop, Tobias

    2013-01-01

    The metastatic colonization of the brain by carcinoma cells is still barely understood, in particular when considering interactions with the host tissue. The colonization comes with a substantial destruction of the surrounding host tissue. This leads to activation of damage responses by resident innate immune cells to protect, repair, and organize the wound healing, but may distract from tumoricidal actions. We recently demonstrated that microglia, innate immune cells of the CNS, assist carci...

  8. SSVEP response is related to functional brain network topology entrained by the flickering stimulus.

    Directory of Open Access Journals (Sweden)

    Yangsong Zhang

    Full Text Available Previous studies have shown that the brain network topology correlates with the cognitive function. However, few studies have investigated the relationship between functional brain networks that process sensory inputs and outputs. In this study, we focus on steady-state paradigms using a periodic visual stimulus, which are increasingly being used in both brain-computer interface (BCI and cognitive neuroscience researches. Using the graph theoretical analysis, we investigated the relationship between the topology of functional networks entrained by periodic stimuli and steady state visually evoked potentials (SSVEP using two frequencies and eleven subjects. First, the entire functional network (Network 0 of each frequency for each subject was constructed according to the coherence between electrode pairs. Next, Network 0 was divided into three sub-networks, in which the connection strengths were either significantly (positively for Network 1, negatively for Network 3 or non-significantly (Network 2 correlated with the SSVEP responses. Our results revealed that the SSVEP responses were positively correlated to the mean functional connectivity, clustering coefficient, and global and local efficiencies, while these responses were negatively correlated with the characteristic path length of Networks 0, 1 and 2. Furthermore, the strengths of these connections that significantly correlated with the SSVEP (both positively and negatively were mainly found to be long-range connections between the parietal-occipital and frontal regions. These results indicate that larger SSVEP responses correspond with better functional network topology structures. This study may provide new insights for understanding brain mechanisms when using SSVEPs as frequency tags.

  9. Physical attractiveness and sex as modulatory factors of empathic brain responses to pain

    OpenAIRE

    Kamila Jankowiak Siuda; Krystyna Rymarczyk; Artur Marchewka

    2015-01-01

    Empathy is a process that comprises affective sharing, imagining, and understanding the emotions and mental states of others. The brain structures involved in empathy for physical pain include the anterior insula (AI), and the anterior cingulate cortex (ACC). High empathy may lead people to undertake pro-social behaviour. It is important to understand how this process can be changed, and what factors these empathic responses depend on. Physical attractiveness is a major social and evolutiona...

  10. Physical attractiveness and sex as modulatory factors of empathic brain responses to pain

    OpenAIRE

    Jankowiak-Siuda, Kamila; Rymarczyk, Krystyna; Żurawski, Łukasz; Jednoróg, Katarzyna; Marchewka, Artur

    2015-01-01

    Empathy is a process that comprises affective sharing, imagining, and understanding the emotions and mental states of others. The brain structures involved in empathy for physical pain include the anterior insula (AI), and the anterior cingulate cortex (ACC). High empathy may lead people to undertake pro-social behavior. It is important to understand how this process can be changed, and what factors these empathic responses depend on. Physical attractiveness is a major social and evolutional ...

  11. Brain responses to repeated visual experience among low and high sensation seekers: role of boredom susceptibility

    OpenAIRE

    Jiang, Yang; Lianekhammy, Joann; Lawson, Adam; Guo, Chunyan; ynam, Donald; Joseph, Jane E.; Gold, Brian T.; Kelly, Thomas H.

    2009-01-01

    To better understand individual differences in sensation seeking and its components, including boredom susceptibility and experience seeking, we examined brain responses of high and low sensation seekers during repeated visual experience. Individuals scoring in the top and bottom quartiles from a college-aged population on the Brief Sensation-Seeking Scale (BSSS) participated in an event-related potentials (ERPs) experiment. Line drawings of common objects were randomly intermixed and present...

  12. Managing health worker migration: a qualitative study of the Philippine response to nurse brain drain

    Directory of Open Access Journals (Sweden)

    Dimaya Roland M

    2012-12-01

    Full Text Available Abstract Background The emigration of skilled nurses from the Philippines is an ongoing phenomenon that has impacted the quality and quantity of the nursing workforce, while strengthening the domestic economy through remittances. This study examines how the development of brain drain-responsive policies is driven by the effects of nurse migration and how such efforts aim to achieve mind-shifts among nurses, governing and regulatory bodies, and public and private institutions in the Philippines and worldwide. Methods Interviews and focus group discussions were conducted to elicit exploratory perspectives on the policy response to nurse brain drain. Interviews with key informants from the nursing, labour and immigration sectors explored key themes behind the development of policies and programmes that respond to nurse migration. Focus group discussions were held with practising nurses to understand policy recipients’ perspectives on nurse migration and policy. Results Using the qualitative data, a thematic framework was created to conceptualize participants’ perceptions of how nurse migration has driven the policy development process. The framework demonstrates that policymakers have recognised the complexity of the brain drain phenomenon and are crafting dynamic policies and programmes that work to shift domestic and global mindsets on nurse training, employment and recruitment. Conclusions Development of responsive policy to Filipino nurse brain drain offers a glimpse into a domestic response to an increasingly prominent global issue. As a major source of professionals migrating abroad for employment, the Philippines has formalised efforts to manage nurse migration. Accordingly, the Philippine paradigm, summarised by the thematic framework presented in this paper, may act as an example for other countries that are experiencing similar shifts in healthcare worker employment due to migration.

  13. Diet-Induced Weight Loss alters Functional Brain Responses during an Episodic Memory Task

    OpenAIRE

    Boraxbekk, Carl-Johan; Stomby, Andreas; Ryberg, Mats; Lindahl, Bernt; Larsson, Christel; Nyberg, Lars; Olsson, Tommy

    2015-01-01

    Objective: It has been suggested that overweight is negatively associated with cognitive functions. The aim of this study was to investigate whether a reduction in body weight by dietary interventions could improve episodic memory performance and alter associated functional brain responses in overweight and obese women. Methods: 20 overweight postmenopausal women were randomized to either a modified paleolithic diet or a standard diet adhering to the Nordic Nutrition Recommendations for 6 mon...

  14. Brain responses to body image stimuli but not food are altered in women with bulimia nervosa

    OpenAIRE

    Van den Eynde, Frederique; Giampietro, Vincent; Simmons, Andrew; Uher, Rudolf; Andrew, Chris M; Harvey, Philippe-Olivier; Campbell, Iain C.; Schmidt, Ulrike

    2013-01-01

    Background Research into the neural correlates of bulimia nervosa (BN) psychopathology remains limited. Methods In this functional magnetic resonance imaging study, 21 BN patients and 23 healthy controls (HCs) completed two paradigms: 1) processing of visual food stimuli and 2) comparing their own appearance with that of slim women. Participants also rated food craving and anxiety levels. Results Brain activation patterns in response to food cues did not differ between women with and without ...

  15. Violence: heightened brain attentional network response is selectively muted in Down syndrome

    OpenAIRE

    Anderson, Jeffrey S.; Treiman, Scott M.; Ferguson, Michael A.; Nielsen, Jared A.; Edgin, Jamie O.; Dai, Li; Gerig, Guido; Korenberg, Julie R.

    2015-01-01

    Background The ability to recognize and respond appropriately to threat is critical to survival, and the neural substrates subserving attention to threat may be probed using depictions of media violence. Whether neural responses to potential threat differ in Down syndrome is not known. Methods We performed functional MRI scans of 15 adolescent and adult Down syndrome and 14 typically developing individuals, group matched by age and gender, during 50 min of passive cartoon viewing. Brain activ...

  16. Sex differences in synaptic plasticity in stress-responsive brain regions following chronic variable stress

    OpenAIRE

    Carvalho-Netto, Eduardo F.; Myers, Brent; Jones, Kenneth; Solomon, Matia B.; Herman, James P.

    2011-01-01

    Increased stress responsiveness is implicated in the etiology of mood and anxiety disorders, including depression and post-traumatic stress disorder. Additionally, stress-related affective disorders have a higher incidence in women than men. Chronic stress in rodents produces numerous neuromorphological changes in a variety of limbic brain regions. Here, we examined the sex-dependent differences in presynaptic innervation of the paraventricular nucleus of the hypothalamus (PVN), prefrontal co...

  17. Response inhibition in children with and without ADHD after traumatic brain injury

    OpenAIRE

    Ornstein, Tisha J.; Psych, C.; Max, Jeffrey E.; Schachar, Russell; Dennis, Maureen; Barnes, Marcia; Ewing-Cobbs, Linda; Levin, Harvey S.

    2012-01-01

    Children with attention-deficit/hyperactivity disorder (ADHD) and traumatic brain injury (TBI) show deficient response inhibition. ADHD itself is a common consequence of TBI, known as secondary ADHD (S-ADHD). Similarity in inhibitory control in children with TBI, S-ADHD, and ADHD would implicate impaired frontostriatal systems; however, it is first necessary to delineate similarities and differences in inhibitory control in these conditions. We compared performance of children with ADHD and t...

  18. From stimuli to motor responses : Decoding rules and decision mechanisms in the human brain

    OpenAIRE

    Bode, S

    2010-01-01

    In a dynamically changing environment, we are constantly required to flexibly react to stimuli. It is therefore necessary to adapt behaviour to environmental cues, as well as to successfully perceive relevant stimuli. The present work addressed the question of which brain areas form the basis for task preparation and decisions along the processing chain from stimuli to responses. It combined functional magnetic resonance imaging with multivariate pattern classification to search for the encod...

  19. MicroRNA responses to focal cerebral ischemia in male and female mouse brain

    OpenAIRE

    Lusardi, Theresa A; Murphy, Stephanie J.; Phillips, Jay I.; Chen, Yingxin; Catherine M Davis; Young, Jennifer M.; Thompson, Simon J.; Saugstad, Julie A

    2014-01-01

    Stroke occurs with greater frequency in men than in women across diverse ethnic backgrounds and nationalities. Work from our lab and others have revealed a sex-specific sensitivity to cerebral ischemia whereby males exhibit a larger extent of brain damage resulting from an ischemic event compared to females. Previous studies revealed that microRNA (miRNA) expression is regulated by cerebral ischemia in males; however, no studies to date have examined the effect of ischemia on miRNA responses ...

  20. Brain functional near infrared spectroscopy in human infants : cerebral cortical haemodynamics coupled to neuronal activation in response to sensory stimulation

    OpenAIRE

    Bartocci, Marco

    2006-01-01

    The assessment of cortical activation in the neonatal brain is crucial in the study of brain development, as it provides precious information for how the newborn infant processes external or internal stimuli. Thus far functional studies of neonates aimed to assess cortical responses to certain external stimuli are very few, due to the lack of suitable techniques to monitor brain activity of the newborn. Near Infrared Spectroscopy (NIRS) has been found to be suitable for func...

  1. The effect of combined hormonal contraceptives use on brain reactivity during response inhibition.

    Science.gov (United States)

    Gingnell, Malin; Bannbers, Elin; Engman, Jonas; Frick, Andreas; Moby, Lena; Wikström, Johan; Sundström-Poromaa, Inger

    2016-04-01

    Objectives Cognitive control, which can be described as the ability to moderate impulses, has not previously been investigated in users of combined hormonal contraception (CHC). Given the suggested modulatory role of ovarian steroids in prefrontal dopaminergic function, which in turn taps into cognitive control, this randomised, double-blinded, placebo-controlled oral contraceptive trial set out to investigate the brain activity pattern during response inhibition in CHC users. Methods Thirty-four women were randomised to one treatment cycle with a levonorgestrel-containing CHC or placebo. The women performed a Go/NoGo task to measure brain activity during response inhibition by use of event-related functional magnetic resonance imaging (fMRI) prior to and during the CHC/placebo treatment cycle. Results No differences between CHC and placebo users in number of correct inhibitions were found during treatment, but only women on CHC significantly improved their performance between the baseline and treatment assessments. During the treatment cycle CHC users displayed decreased activity in the right middle frontal gyrus in comparison with placebo users. No other significant activations were evident between treatment groups or within groups. Conclusion Overall, CHC use had marginal effects on brain activity during response inhibition. If anything, the findings of the study may suggest reduced effort or increased efficiency in maintaining orbitofrontal cortex inhibitory cognitive control when using a combined oral contraceptive. PMID:26291330

  2. Response-driven imaging biomarkers for predicting radiation necrosis of the brain

    International Nuclear Information System (INIS)

    Radiation necrosis is an uncommon but severe adverse effect of brain radiation therapy (RT). Current predictive models based on radiation dose have limited accuracy. We aimed to identify early individual response biomarkers based upon diffusion tensor (DT) imaging and incorporated them into a response model for prediction of radiation necrosis. Twenty-nine patients with glioblastoma received six weeks of intensity modulated RT and concurrent temozolomide. Patients underwent DT-MRI scans before treatment, at three weeks during RT, and one, three, and six months after RT. Cases with radiation necrosis were classified based on generalized equivalent uniform dose (gEUD) of whole brain and DT index early changes in the corpus callosum and its substructures. Significant covariates were used to develop normal tissue complication probability models using binary logistic regression. Seven patients developed radiation necrosis. Percentage changes of radial diffusivity (RD) in the splenium at three weeks during RT and at six months after RT differed significantly between the patients with and without necrosis (p = 0.05 and p = 0.01). Percentage change of RD at three weeks during RT in the 30 Gy dose–volume of the splenium and brain gEUD combined yielded the best-fit logistic regression model. Our findings indicate that early individual response during the course of RT, assessed by radial diffusivity, has the potential to aid the prediction of delayed radiation necrosis, which could provide guidance in dose-escalation trials. (paper)

  3. Attachment style dimensions are associated with brain activity in response to gaze interaction.

    Science.gov (United States)

    Cecchini, Marco; Iannoni, Maria Elena; Pandolfo, Anna Lucia; Aceto, Paola; Lai, Carlo

    2015-01-01

    Aim of the present study was to investigate the time course of brain processes involved in the visual perception of different gaze interactions in woman-child dyads and the association between attachment dimensions and brain activation during the presentation of gaze interactions. The hypothesis was that the woman avoidance will produce a greater activation of primary somatosensory and limbic areas. The attachment styles dimensions avoidant-related will be associated with fronto-limbic brain intensity during the convergence of gaze. Electroencephalogram (EEG) data were recorded using a 256-channel HydroCel Geodesic Sensor Net in 44 female subjects (age: 24 ± 2 years). Event-related potential (ERP) components and standardized low-resolution electromagnetic tomography (sLORETA) were analyzed. Participants were administered the attachment style questionnaire before EEG task. A lower P350 latency was found in the fronto-central montage in response to woman avoidance. sLORETA analysis showed a greater intensity of limbic and primary somatosensory areas in response to woman avoidance compared to the others gaze interactions. In response to convergence gaze, the confidence attachment dimension was negatively correlated with the intensities of the right temporal and limbic areas, and the relationships as secondary attachment dimension were positively correlated with the intensities of the bilateral frontal areas and of the left parietal area. PMID:25568957

  4. MicroRNA: Small RNA mediators of the brains genomic response to environmental stress.

    Science.gov (United States)

    Hollins, Sharon L; Cairns, Murray J

    2016-08-01

    The developmental processes that establish the synaptic architecture of the brain while retaining capacity for activity-dependent remodeling, are complex and involve a combination of genetic and epigenetic influences. Dysregulation of these processes can lead to problems with neural circuitry which manifest in humans as a range of neurodevelopmental syndromes, such as schizophrenia, bipolar disorder and fragile X mental retardation. Recent studies suggest that prenatal, postnatal and intergenerational environmental factors play an important role in the aetiology of stress-related psychopathology. A number of these disorders have been shown to display epigenetic changes in the postmortem brain that reflect early life experience. These changes affect the regulation of gene expression though chromatin remodeling (transcriptional) and post-transcriptional influences, especially small noncoding microRNA (miRNA). These dynamic and influential molecules appear to play an important function in both brain development and its adaption to stress. In this review, we examine the role of miRNA in mediating the brain's response to both prenatal and postnatal environmental perturbations and explore how stress- induced alterations in miRNA expression can regulate the stress response via modulation of the immune system. Given the close relationship between environmental stress, miRNA, and brain development/function, we assert that miRNA hold a significant position at the molecular crossroads between neural development and adaptations to environmental stress. A greater understanding of the dynamics that mediate an individual's predisposition to stress-induced neuropathology has major human health benefits and is an important area of research. PMID:27317386

  5. Copper Exposure Perturbs Brain Inflammatory Responses and Impairs Clearance of Amyloid-Beta.

    Science.gov (United States)

    Kitazawa, Masashi; Hsu, Heng-Wei; Medeiros, Rodrigo

    2016-07-01

    Copper promotes a toxic buildup of amyloid-beta (Aβ) and neurofibrillary tangle pathology in the brain, and its exposure may increase the risk for Alzheimer's disease (AD). However, underlying molecular mechanisms by which copper triggers such pathological changes remain largely unknown. We hypothesized that the copper exposure perturbs brain inflammatory responses, leading to impairment of Aβ clearance from the brain parenchyma. Here, we investigated whether copper attenuated Aβ clearance by microglial phagocytosis or by low-density lipoprotein-related receptor protein-1 (LRP1) dependent transcytosis in both in vitro and in vivo When murine monocyte BV2 cells were exposed to copper, their phagocytic activation induced by fibrillar Aβ or LPS was significantly reduced, while the secretion of pro-inflammatory cytokines, such as IL-1β, TNF-α, and IL-6, were increased. Interestingly, not only copper itself but also IL-1β, IL-6, or TNF-α were capable of markedly reducing the expression of LRP1 in human microvascular endothelial cells (MVECs) in a concentration-dependent manner. While copper-mediated downregulation of LRP1 was proteasome-dependent, the cytokine-induced loss of LRP1 was proteasome- or lysosome-independent. In the mouse model, copper exposure also significantly elevated neuroinflammation and downregulated LRP1 in the brain, consistent with our in vitro results. Taken together, our findings support the pathological impact of copper on inflammatory responses and Aβ clearance in the brain, which could serve as key mechanisms to explain, in part, the copper exposure as an environmental risk factor for AD. PMID:27122238

  6. Hemodynamic pattern in myocardial infarction patients at the common stages of rehabilitation

    International Nuclear Information System (INIS)

    Integrated body rheography, radiocardiography and radionuclide ventriculography were used to investigate hemodynamic changes in 101 myocardial infarction patients during the hospital stage of the disease. Changes in major hemodynamic parameters were demonstrated by the end of the 1st week and when walking was resumed. At the resumed-walking stage, the mechanism of declining stroke and cardiac indices was shown to depend on physical activation rates. Hemodynamic response is mostly conditioned by myocardial insufficiency when walking is resumed rapidly during the 2nd week, and by smaller venous return due to hypovolemia where it is resumed slowly during the 4th week. Expanding motion regimens at slow rates results in persistent hemodynamic disturbances in myocardial infarction patients

  7. Assessing paedophilia based on the haemodynamic brain response to face images

    DEFF Research Database (Denmark)

    Ponseti, Jorge; Granert, Oliver; Van Eimeren, Thilo;

    2016-01-01

    OBJECTIVES: Objective assessment of sexual preferences may be of relevance in the treatment and prognosis of child sexual offenders. Previous research has indicated that this can be achieved by pattern classification of brain responses to sexual child and adult images. Our recent research showed...... misclassified participants (three false positives), corresponding to a specificity of 91% and a sensitivity of 95%. CONCLUSIONS: These results indicate that the functional response to facial stimuli can be reliably used for fMRI-based classification of paedophilia, bypassing the problem of showing child sexual...

  8. Promoting Motor Function by Exercising the Brain

    Directory of Open Access Journals (Sweden)

    Stephane Perrey

    2013-01-01

    Full Text Available Exercise represents a behavioral intervention that enhances brain health and motor function. The increase in cerebral blood volume in response to physical activity may be responsible for improving brain function. Among the various neuroimaging techniques used to monitor brain hemodynamic response during exercise, functional near-infrared spectroscopy could facilitate the measurement of task-related cortical responses noninvasively and is relatively robust with regard to the subjects’ motion. Although the components of optimal exercise interventions have not been determined, evidence from animal and human studies suggests that aerobic exercise with sufficiently high intensity has neuroprotective properties and promotes motor function. This review provides an insight into the effect of physical activity (based on endurance and resistance exercises on brain function for producing movement. Since most progress in the study of brain function has come from patients with neurological disorders (e.g., stroke and Parkinson’s patients, this review presents some findings emphasizing training paradigms for restoring motor function.

  9. Predictive value of brain perfusion SPECT for rTMS response in pharmacoresistant depression

    International Nuclear Information System (INIS)

    The aim of this study was to determine the predictive value of whole-brain voxel-based regional cerebral blood flow (rCBF) for repetitive transcranial magnetic stimulation (rTMS) response in patients with pharmacoresistant depression. Thirty-three right-handed patients who met DSM-IV criteria for major depressive disorder (unipolar or bipolar depression) were included before rTMS. rTMS response was defined as at least 50% reduction in the baseline Beck Depression Inventory scores. The predictive value of 99mTc-ethyl cysteinate dimer (ECD) single photon emission computed tomography (SPECT) for rTMS response was studied before treatment by comparing rTMS responders to non-responders at voxel level using Statistical Parametric Mapping (SPM) (p 0.10). In comparison to responders, non-responders showed significant hypoperfusions (p < 0.001, uncorrected) in the left medial and bilateral superior frontal cortices (BA10), the left uncus/parahippocampal cortex (BA20/BA35) and the right thalamus. The area under the curve for the combination of SPECT clusters to predict rTMS response was 0.89 (p < 0.001). Sensitivity, specificity, positive predictive value and negative predictive value for the combination of clusters were: 94, 73, 81 and 92%, respectively. This study shows that, in pharmacoresistant depression, pretreatment rCBF of specific brain regions is a strong predictor for response to rTMS in patients with homogeneous demographic/clinical features. (orig.)

  10. SU-E-QI-12: Morphometry Based Measurements of the Structural Response to Whole Brain Radiation

    International Nuclear Information System (INIS)

    Purpose: Although state of the art radiation therapy techniques for treating intracranial malignancies have eliminated acute brain injury, cognitive impairment occurs in 50–90% of patients who survive >6mo post irradiation. Quantitative characterization of therapy response is needed to facilitate therapeutic strategies to minimize radiation induced cognitive impairment [1]. Deformation based morphometry techniques [2, 3] are presented as a quantitative imaging biomarker of therapy response in patients receiving whole brain radiation for treating medulloblastoma. Methods: Post-irradiation magnetic resonance imaging (MRI) data sets were retrospectively analyzed in N=15 patients, >60 MR image datasets. As seen in Fig 1(a), volume changes at multiple time points post-irradiation were quantitatively measured in the cerebrum and ventricles with respect to pre-irradiation MRI. A high resolution image Template, was registered to the pre-irradiation MRI of each patient to create a brain atlas for the cerebrum, cerebellum, and ventricles. Skull stripped images for each patient were registered to the initial pre-treatment scan. Average volume changes in the labeled regions were measured using the determinant of the displacement field Jacobian. Results: Longitudinal measurements, Fig 1(b-c), show a negative correlation p=.06, of the cerebral volume change with the time interval from irradiation. A corresponding positive correlation, p=.01, between ventricular volume change and time interval from irradiation is seen. One sample t-test for correlations were computed using a Spearman method. An average decrease in cerebral volume, p=.08, and increase in ventricular volume, p<.001, was observed. The radiation dose was seen directly proportional to the induced volume changes in the cerebrum, r=−.44, p<.001, Fig 1(d). Conclusion: Results indicate that morphometric monitoring of brain tissue volume changes may potentially be used to quantitatively assess toxicity and response to

  11. SU-E-QI-12: Morphometry Based Measurements of the Structural Response to Whole Brain Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Fuentes, D; Castillo, R; Castillo, E; Guerrero, T [UT MD Anderson Cancer Center, Houston, TX (United States)

    2014-06-15

    Purpose: Although state of the art radiation therapy techniques for treating intracranial malignancies have eliminated acute brain injury, cognitive impairment occurs in 50–90% of patients who survive >6mo post irradiation. Quantitative characterization of therapy response is needed to facilitate therapeutic strategies to minimize radiation induced cognitive impairment [1]. Deformation based morphometry techniques [2, 3] are presented as a quantitative imaging biomarker of therapy response in patients receiving whole brain radiation for treating medulloblastoma. Methods: Post-irradiation magnetic resonance imaging (MRI) data sets were retrospectively analyzed in N=15 patients, >60 MR image datasets. As seen in Fig 1(a), volume changes at multiple time points post-irradiation were quantitatively measured in the cerebrum and ventricles with respect to pre-irradiation MRI. A high resolution image Template, was registered to the pre-irradiation MRI of each patient to create a brain atlas for the cerebrum, cerebellum, and ventricles. Skull stripped images for each patient were registered to the initial pre-treatment scan. Average volume changes in the labeled regions were measured using the determinant of the displacement field Jacobian. Results: Longitudinal measurements, Fig 1(b-c), show a negative correlation p=.06, of the cerebral volume change with the time interval from irradiation. A corresponding positive correlation, p=.01, between ventricular volume change and time interval from irradiation is seen. One sample t-test for correlations were computed using a Spearman method. An average decrease in cerebral volume, p=.08, and increase in ventricular volume, p<.001, was observed. The radiation dose was seen directly proportional to the induced volume changes in the cerebrum, r=−.44, p<.001, Fig 1(d). Conclusion: Results indicate that morphometric monitoring of brain tissue volume changes may potentially be used to quantitatively assess toxicity and response to

  12. Spatial and Temporal Brain Responses to Noxious Heat Thermal Stimuli in Burning Mouth Syndrome.

    Science.gov (United States)

    Shinozaki, T; Imamura, Y; Kohashi, R; Dezawa, K; Nakaya, Y; Sato, Y; Watanabe, K; Morimoto, Y; Shizukuishi, T; Abe, O; Haji, T; Tabei, K; Taira, M

    2016-09-01

    Burning mouth syndrome (BMS) is an idiopathic orofacial pain condition. Although the pathophysiology of BMS is not clearly understood, central and peripheral neuropathic mechanisms are thought to be involved. The authors compared brain response to noxious heat stimuli in 16 right-handed women with primary BMS and 15 sex- and age-matched right-handed healthy female controls. A thermal stimulus sequence of 32 °C to 40 °C to 32 °C to 49 °C was repeated 4 times in a cycle. Warm and noxious heat stimuli were delivered with a Peltier thermode placed on the right palm or right lower lip for 32 s each in a session. Functional magnetic resonance imaging data were obtained by recording echoplanar images with a block design. Statistical Parametric Mapping 8 software was used to analyze the data. Patients and controls both reported feeling more pain during palm stimulation than during lip stimulation. Repetition of noxious heat stimulus on the lower lip but not on the palm induced habituation in brain activity in the cingulate cortex without reduction in pain perception. Multiple regression analysis revealed a correlation between perceived pain intensity and suppression of brain activity in the anterior cingulate cortex when the repeated thermal sequence was applied at the lower lip. Furthermore, the response of the parahippocampal area differed in BMS patients and controls when the same repeated thermal sequence was applied at the palm. The authors' findings indicate that BMS patients show specific brain responses due to impaired function of the central and peripheral nervous systems (clinical trial registration: UMIN000015002). PMID:27302878

  13. Hemodynamic changes after levothyroxine treatment in subclinical hypothyroidism

    DEFF Research Database (Denmark)

    Faber, J; Petersen, L; Wiinberg, N;

    2002-01-01

    In hypothyroidism, lack of thyroid hormones results in reduced cardiac function (cardiac output [CO]), and an increase of systemic vascular resistance (SVR). We speculated whether hemodynamic regulation in subjects with subclinical hypothyroidism (SH) (defined as mildly elevated thyrotropin [TSH...... <0.05). These changes were qualitatively similar but quantitatively less pronounced than in 15 women with overt hypothyroidism, also studied. Taking the two groups together (n = 31), pretreatment thyroid function (expressed as either TSH or free T(4) estimate) correlated to CO and SVR as well as the...... changes induced by LT(4) (p <0.05), i.e., the lower the thyroid function the lower the CO and the higher the SVR, and the greater the response to LT(4). We conclude, that LT(4) treatment in SH results in changes in hemodynamic parameters of potentially beneficial character. SH and overt hypothyroidism...

  14. Use of frontal lobe hemodynamics as reinforcement signals to an adaptive controller.

    Directory of Open Access Journals (Sweden)

    Marcello M DiStasio

    Full Text Available Decision-making ability in the frontal lobe (among other brain structures relies on the assignment of value to states of the animal and its environment. Then higher valued states can be pursued and lower (or negative valued states avoided. The same principle forms the basis for computational reinforcement learning controllers, which have been fruitfully applied both as models of value estimation in the brain, and as artificial controllers in their own right. This work shows how state desirability signals decoded from frontal lobe hemodynamics, as measured with near-infrared spectroscopy (NIRS, can be applied as reinforcers to an adaptable artificial learning agent in order to guide its acquisition of skills. A set of experiments carried out on an alert macaque demonstrate that both oxy- and deoxyhemoglobin concentrations in the frontal lobe show differences in response to both primarily and secondarily desirable (versus undesirable stimuli. This difference allows a NIRS signal classifier to serve successfully as a reinforcer for an adaptive controller performing a virtual tool-retrieval task. The agent's adaptability allows its performance to exceed the limits of the NIRS classifier decoding accuracy. We also show that decoding state desirabilities is more accurate when using relative concentrations of both oxyhemoglobin and deoxyhemoglobin, rather than either species alone.

  15. Relations between peripheral and brain serotonin measures and behavioural responses in a novelty test in pigs.

    Science.gov (United States)

    Ursinus, Winanda W; Bolhuis, J Elizabeth; Zonderland, Johan J; Rodenburg, T Bas; de Souza, Adriana S; Koopmanschap, Rudie E; Kemp, Bas; Korte-Bouws, Gerdien A H; Korte, S Mechiel; van Reenen, Cornelis G

    2013-06-13

    Pigs differ in their behavioural responses towards environmental challenges. Individual variation in maladaptive responses such as tail biting, may partly originate from underlying biological characteristics related to (emotional) reactivity to challenges and serotonergic system functioning. Assessing relations between behavioural responses and brain and blood serotonin parameters may help in understanding susceptibility to the development of maladaptive responses. The objective of the current study was, therefore, to assess the relationship between the pigs' serotonergic parameters measured in both blood and brain, and the behaviour of pigs during a novelty test. Pigs (n=31) were subjected to a novelty test at 11weeks of age, consisting of 5-min novel environment exposure after which a novel object (a bucket) was introduced for 5min. Whole blood serotonin, platelet serotonin level, and platelet serotonin uptake were determined at 13weeks of age. Levels of serotonin, its metabolite and serotonin turnover were determined at 19weeks of age in the frontal cortex, hypothalamus and hippocampus. The behaviour of the pigs was different during exposure to a novel object compared to the novel environment only, with more fear-related behaviours exhibited during novel object exposure. Platelet serotonin level and brain serotonergic parameters in the hippocampus were interrelated. Notably, the time spent exploring the test arena was significantly correlated with both platelet serotonin level and right hippocampal serotonin activity (turnover and concentration). In conclusion, the existence of an underlying biological trait - possibly fearfulness - may be involved in the pig's behavioural responses toward environmental challenges, and this is also reflected in serotonergic parameters. PMID:23685231

  16. Transcriptomic responses in mouse brain exposed to chronic excess of the neurotransmitter glutamate

    Directory of Open Access Journals (Sweden)

    Pal Ranu

    2010-06-01

    Full Text Available Abstract Background Increases during aging in extracellular levels of glutamate (Glu, the major excitatory neurotransmitter in the brain, may be linked to chronic neurodegenerative diseases. Little is known about the molecular responses of neurons to chronic, moderate increases in Glu levels. Genome-wide gene expression in brain hippocampus was examined in a unique transgenic (Tg mouse model that exhibits moderate Glu hyperactivity throughout the lifespan, the neuronal Glutamate dehydrogenase (Glud1 mouse, and littermate 9 month-old wild type mice. Results Integrated bioinformatic analyses on transcriptomic data were used to identify bio-functions, pathways and gene networks underlying neuronal responses to increased Glu synaptic release. Bio-functions and pathways up-regulated in Tg mice were those associated with oxidative stress, cell injury, inflammation, nervous system development, neuronal growth, and synaptic transmission. Increased gene expression in these functions and pathways indicated apparent compensatory responses offering protection against stress, promoting growth of neuronal processes (neurites and re-establishment of synapses. The transcription of a key gene in the neurite growth network, the kinase Ptk2b, was significantly up-regulated in Tg mice as was the activated (phosphorylated form of the protein. In addition to genes related to neurite growth and synaptic development, those associated with neuronal vesicle trafficking in the Huntington's disease signalling pathway, were also up-regulated. Conclusions This is the first study attempting to define neuronal gene expression patterns in response to chronic, endogenous Glu hyperactivity at brain synapses. The patterns observed were characterized by a combination of responses to stress and stimulation of nerve growth, intracellular transport and recovery.

  17. Branding and a child's brain: an fMRI study of neural responses to logos.

    Science.gov (United States)

    Bruce, Amanda S; Bruce, Jared M; Black, William R; Lepping, Rebecca J; Henry, Janice M; Cherry, Joseph Bradley C; Martin, Laura E; Papa, Vlad B; Davis, Ann M; Brooks, William M; Savage, Cary R

    2014-01-01

    Branding and advertising have a powerful effect on both familiarity and preference for products, yet no neuroimaging studies have examined neural response to logos in children. Food advertising is particularly pervasive and effective in manipulating choices in children. The purpose of this study was to examine how healthy children's brains respond to common food and other logos. A pilot validation study was first conducted with 32 children to select the most culturally familiar logos, and to match food and non-food logos on valence and intensity. A new sample of 17 healthy weight children were then scanned using functional magnetic resonance imaging. Food logos compared to baseline were associated with increased activation in orbitofrontal cortex and inferior prefrontal cortex. Compared to non-food logos, food logos elicited increased activation in posterior cingulate cortex. Results confirmed that food logos activate some brain regions in children known to be associated with motivation. This marks the first study in children to examine brain responses to culturally familiar logos. Considering the pervasiveness of advertising, research should further investigate how children respond at the neural level to marketing. PMID:22997054

  18. Noninvasive optical evaluation of low frequency oscillations in prefrontal cortex hemodynamics during verbal working memory

    Science.gov (United States)

    Li, Ting; Zhao, Yue; Li, Kai; Sun, Yunlong

    2014-03-01

    The low frequency oscillation (LFO) around 0.1 Hz has been observed recently in cerebral hemodynamic signals during rest/sleep, enhanced breathing, and head- up-tilting, showing that cerebral autoregulation can be accessed by LFOs. However, many brain function researches require direct measurement of LFOs during specified brain function activities. This pilot study explored using near-infrared spectroscopy/imaging (NIRS) to noninvasively and simultaneously detect LFOs of prefrontal cerebral hemodynamics (i.e., oxygenated/deoxygenated/total hemoglobin concentration: △[oxy-Hb]/ △[deoxy-Hb]/ △[tot-Hb]) during N-back visual verbal working memory task. The LFOs were extracted from the measured variables using power spectral analysis. We found the brain activation sites struck clear LFOs while other sites did not. The LFO of △[deoxy-Hb] acted as a negative pike and ranged in (0.05, 0.1) Hz, while LFOs of △[oxy-Hb] and △[tot-Hb] acted as a positive pike and ranged in (0.1, 0.15) Hz. The amplitude difference and frequency lag between △[deoxy-Hb] and △[oxy-Hb]/ △[tot-Hb] produced a more focused and sensitive activation map compare to hemodynamic amplitude-quantified activation maps. This study observed LFOs in brain activities and showed strong potential of LFOs in accessing brain functions.

  19. Metastatic brain cancer: prediction of response to whole-brain helical tomotherapy with simultaneous intralesional boost for metastatic disease using quantitative MR imaging features

    Science.gov (United States)

    Sharma, Harish; Bauman, Glenn; Rodrigues, George; Bartha, Robert; Ward, Aaron

    2014-03-01

    The sequential application of whole brain radiotherapy (WBRT) and more targeted stereotactic radiosurgery (SRS) is frequently used to treat metastatic brain tumors. However, SRS has side effects related to necrosis and edema, and requires separate and relatively invasive localization procedures. Helical tomotherapy (HT) allows for a SRS-type simultaneous infield boost (SIB) of multiple brain metastases, synchronously with WBRT and without separate stereotactic procedures. However, some patients' tumors may not respond to HT+SIB, and would be more appropriately treated with radiosurgery or conventional surgery despite the additional risks and side effects. As a first step toward a broader objective of developing a means for response prediction to HT+SIB, the goal of this study was to investigate whether quantitative measurements of tumor size and appearance (including first- and second-order texture features) on a magnetic resonance imaging (MRI) scan acquired prior to treatment could be used to differentiate responder and nonresponder patient groups after HT+SIB treatment of metastatic disease of the brain. Our results demonstrated that smaller lesions may respond better to this form of therapy; measures of appearance provided limited added value over measures of size for response prediction. With further validation on a larger data set, this approach may lead to a means for prediction of individual patient response based on pre-treatment MRI, supporting appropriate therapy selection for patients with metastatic brain cancer.

  20. Brain caspase-3 and intestinal FABP responses in preterm and term rats submitted to birth asphyxia

    Directory of Open Access Journals (Sweden)

    R.L. Figueira

    2016-01-01

    Full Text Available Neonatal asphyxia can cause irreversible injury of multiple organs resulting in hypoxic-ischemic encephalopathy and necrotizing enterocolitis (NEC. This injury is dependent on time, severity, and gestational age, once the preterm babies need ventilator support. Our aim was to assess the different brain and intestinal effects of ischemia and reperfusion in neonate rats after birth anoxia and mechanical ventilation. Preterm and term neonates were divided into 8 subgroups (n=12/group: 1 preterm control (PTC, 2 preterm ventilated (PTV, 3 preterm asphyxiated (PTA, 4 preterm asphyxiated and ventilated (PTAV, 5 term control (TC, 6 term ventilated (TV, 7 term asphyxiated (TA, and 8 term asphyxiated and ventilated (TAV. We measured body, brain, and intestine weights and respective ratios [(BW, (BrW, (IW, (BrW/BW and (IW/BW]. Histology analysis and damage grading were performed in the brain (cortex/hippocampus and intestine (jejunum/ileum tissues, as well as immunohistochemistry analysis for caspase-3 and intestinal fatty acid-binding protein (I-FABP. IW was lower in the TA than in the other terms (P<0.05, and the IW/BW ratio was lower in the TA than in the TAV (P<0.005. PTA, PTAV and TA presented high levels of brain damage. In histological intestinal analysis, PTAV and TAV had higher scores than the other groups. Caspase-3 was higher in PTAV (cortex and TA (cortex/hippocampus (P<0.005. I-FABP was higher in PTAV (P<0.005 and TA (ileum (P<0.05. I-FABP expression was increased in PTAV subgroup (P<0.0001. Brain and intestinal responses in neonatal rats caused by neonatal asphyxia, with or without mechanical ventilation, varied with gestational age, with increased expression of caspase-3 and I-FABP biomarkers.

  1. Brain activation for response inhibition under gaming cue distraction in internet gaming disorder.

    Science.gov (United States)

    Liu, Gin-Chung; Yen, Ju-Yu; Chen, Chiao-Yun; Yen, Cheng-Fang; Chen, Cheng-Sheng; Lin, Wei-Chen; Ko, Chih-Hung

    2014-01-01

    We evaluated neural substrates related to the loss of control in college students with internet gaming disorder (IGD). We hypothesized that deficit in response inhibition under gaming cue distraction was the possible mechanism for the loss of control internet use. Eleven cases of IGD and 11 controls performed Go/NoGo tasks with/without gaming distraction in the functional magnetic resonance imaging scanner. When the gaming picture was shown as background while individuals were performing Go/NoGo tasks, the IGD group committed more commission errors. The control group increased their brain activations more over the right dorsolateral prefrontal cortex (DLPFC) and superior parietal lobe under gaming cue distraction in comparison with the IGD group. Furthermore, brain activation of the right DLPFC and superior parietal lobe were negatively associated with performance of response inhibition among the IGD group. The results suggest that the function of response inhibition was impaired under gaming distraction among the IGD group, and individuals with IGD could not activate right DLPFC and superior parietal lobe to keep cognitive control and attention allocation for response inhibition under gaming cue distraction. This mechanism should be addressed in any intervention for IGD. PMID:24388058

  2. 经颅多普勒超声对脑死亡患者颅内血流动力学的观察%Observation of intracranial hemodynamics in brain death through transcranial doppler ultrasound

    Institute of Scientific and Technical Information of China (English)

    王玉珍; 何奕涛

    2012-01-01

    目的 观察脑死亡患者的脑血流频谱演变过程.方法 采用经颅多普勒超声(TCD)检测脑死亡患者双侧大脑中动脉(MCA)的血流情况.结果 20例临床诊断脑死亡患者的MCA血流速度6~37 cm/s,平均(12.13 ±3.15) cm/s.频谱变化有振荡波(舒张期反向波)、钉子波(收缩期尖小波形)、无血流信号三种TCD特征性频谱,并随病情进展依次出现.20例患者均在出现振荡波频谱后8d内出现心跳不可逆停止,其中有90%(18例)的患者血流频谱出现振荡波-钉子波-无血流信号的演变过程.结论 振荡波、钉子波及血流信号消失这三种规律性演变的特征性TCD血流频谱能辅助脑死亡的诊断.%Objective To observe the evolution process of cerebral blood flow spectrum in brain death by transcranial doppler ultrasound.Methods To detect the blood flow of bilateral middle cerebral artery in brain dead patients by transcranial doppler ultrasound.Results Twenty brain dead patients were collected in the study.The blood flow velocity of middle cerebral artery ranged s from 6 to 37cm/s,and the mean velocity was (12.13 ± 3.15)cm/s.There were three characteristic spectrums which include oscillatory wave (reverse wave in diastolic),nails wave (tip small wave in systolic),no blood flow sign,and they appeared in turn accoerding to worsen of the disease.The heartbeat irreversibly stopped within 8 days after the appearing of oscillatory wave,and ninty percent of the cases had the regular blood flow spectrums of oscillatory wave-nails wave-no blood flow sign.Conclusion The three regularly characteristic transcranial doppler ultrasound blood flow spectrums,which include oscillatory wave,nails wave and no blood flow sign could facilitate the diagnosis of brain death.

  3. Phase lagging model of brain response to external stimuli - modeling of single action potential

    CERN Document Server

    Seetharaman, Karthik; Kulish, Vladimir V

    2012-01-01

    In this paper we detail a phase lagging model of brain response to external stimuli. The model is derived using the basic laws of physics like conservation of energy law. This model eliminates the paradox of instantaneous propagation of the action potential in the brain. The solution of this model is then presented. The model is further applied in the case of a single neuron and is verified by simulating a single action potential. The results of this modeling are useful not only for the fundamental understanding of single action potential generation, but also they can be applied in case of neuronal interactions where the results can be verified against the real EEG signal.

  4. Early changes of auditory brain stem evoked response after radiotherapy for nasopharyngeal carcinoma - a prospective study

    Energy Technology Data Exchange (ETDEWEB)

    Lau, S.K.; Wei, W.I.; Sham, J.S.T.; Choy, D.T.K.; Hui, Y. (Queen Mary Hospital, Hong Kong (Hong Kong))

    1992-10-01

    A prospective study of the effect of radiotherapy for nasopharyngeal carcinoma on hearing was carried out on 49 patients who had pure tone, impedance audiometry and auditory brain stem evoked response (ABR) recordings before, immediately, three, six and 12 months after radiotherapy. Fourteen patients complained of intermittent tinnitus after radiotherapy. We found that 11 initially normal ears of nine patients developed a middle ear effusion, three to six months after radiotherapy. There was mixed sensorineural and conductive hearing impairment after radiotherapy. Persistent impairment of ABR was detected immediately after completion of radiotherapy. The waves I-III and I-V interpeak latency intervals were significantly prolonged one year after radiotherapy. The study shows that radiotherapy for nasopharyngeal carcinoma impairs hearing by acting on the middle ear, the cochlea and the brain stem auditory pathway. (Author).

  5. Factors associated with tumor response and survival in radiosurgery for brain metastasis

    International Nuclear Information System (INIS)

    We reviewed our experience with radiosurgery for brain metastasis and focused on factors associated with tumor response and survival. Our study consists of 19 patients with 25 brain metastases who underwent linear accelerator radiosurgery. There was evidence of extra-central nervous system (CNS) tumors in 15 patients. The maximum diameter of the tumors ranged from 3 to 40 mm with a mean of 20 mm. Tumor doses at the isocenter varied from 16 to 25 Gy with a mean of 21 Gy. Eighteen lesions were treated by radiosurgery alone and 7 lesions received combined radiosurgery with fractionated radiotherapy. Of the 11 patients who experienced CNS failure either in or out of the radiosurgery field, 6 patients had salvage radiotherapy. Median survival was 7 months, and the 1-year actuarial survival rate was 40%. Death was due to extra-CNS tumor manifestations in 11 patients. In 3 patients, CNS failure was the cause of death. One died of local progression, and the other 2 died of newly developed metastases. Poor Karnofsky performance scores and the presence of extra-CNS tumors significantly affected 1-year survival in univariate analysis (p<0.05). Local tumor control was achieved in 80% of the lesions. The 1-year actuarial tumor control rate was 51%. Newly developed brain metastases were observed in 7 patients. The tumor diameter was mostly associated with tumor response in multiple regression analysis (p=0.0031). We concluded that radiosurgery is effective in controlling small brain metastases. Survival benefit is expected for those with good performance status and adequately controlled extra-CNS disease. (author)

  6. Radiation protection in hemodynamics work process: the look of the multidisciplinary team

    International Nuclear Information System (INIS)

    The study was conducted in a hemodynamics service of a public hospital in Florianopolis, SC, Brazil. Qualitative research with the participation of 13 professionals from a multidisciplinary team: doctors, technicians, technologists in radiology and nurses. The research material was extracted from the observations, semi-structured interviews and documentary analysis. The responses were grouped into three categories relating to: training of hemodynamic professionals and the perception of radiological protection in the work process; occupational exposure and safety of the professionals of Hemodynamics; and continuing education in hemodynamic service. Professionals are daily exposed to ionizing radiation, and for being long procedures, lead to high levels of exposure in workers. In hemodynamic services the risk of biological effects are cumulative, because radiodiagnostic procedures include issuing the higher doses of ionizing radiation in which the personnel exposure is critical. The workforce in the service researched mostly consists of technical professionals who reported little knowledge of radiation protection and ionizing radiation and that this issue was not addressed during their training. However, despite mention little knowledge about radiological protection, participants demonstrated understand the biological effects, especially with regard to pathologies caused by frequent exposure without protection to ionizing radiation. These professionals said they have no knowledge of the proper use of radiological protection equipment and the dosimeter, and that the institution does not provide all individual protective equipment required for the procedures performed in the hemodynamic service. Permanent education in hemodynamic service is very important part in the work process, though, cited by participants as little effectiveness in the institution, even when the professionals show interest in the area. Knowledge of the team providing hemodynamic service calls

  7. Invasive hemodynamic monitoring in the postoperative period of cardiac surgery

    Directory of Open Access Journals (Sweden)

    Desanka Dragosavac

    1999-08-01

    Full Text Available OBJETIVE: To assess the hemodynamic profile of cardiac surgery patients with circulatory instability in the early postoperative period (POP. METHODS: Over a two-year period, 306 patients underwent cardiac surgery. Thirty had hemodynamic instability in the early POP and were monitored with the Swan-Ganz catheter. The following parameters were evaluated: cardiac index (CI, systemic and pulmonary vascular resistance, pulmonary shunt, central venous pressure (CVP, pulmonary capillary wedge pressure (PCWP, oxygen delivery and consumption, use of vasoactive drugs and of circulatory support. RESULTS: Twenty patients had low cardiac index (CI, and 10 had normal or high CI. Systemic vascular resistance was decreased in 11 patients. There was no correlation between oxygen delivery (DO2 and consumption (VO2, p=0.42, and no correlation between CVP and PCWP, p=0.065. Pulmonary vascular resistance was decreased in 15 patients and the pulmonary shunt was increased in 19. Two patients with CI < 2L/min/m² received circulatory support. CONCLUSION: Patients in the POP of cardiac surgery frequently have a mixed shock due to the systemic inflammatory response syndrome (SIRS. Therefore, invasive hemodynamic monitoring is useful in handling blood volume, choice of vasoactive drugs, and indication for circulatory support.

  8. Fast joint detection-estimation of evoked brain activity in event-related fMRI using a variational approach

    OpenAIRE

    Chaari, Lotfi; Vincent, Thomas; Forbes, Florence; Dojat, Michel; Ciuciu, Philippe

    2013-01-01

    International audience In standard within-subject analyses of event-related fMRI data, two steps are usually performed separately: detection of brain activity and estimation of the hemodynamic response. Because these two steps are inherently linked, we adopt the socalled region-based Joint Detection-Estimation (JDE) framework that addresses this joint issue using a multivariate inference for detection and estimation. JDE is built by making use of a regional bilinear generative model of the...

  9. Hormonal contraceptives suppress oxytocin-induced brain reward responses to the partner's face.

    Science.gov (United States)

    Scheele, Dirk; Plota, Jessica; Stoffel-Wagner, Birgit; Maier, Wolfgang; Hurlemann, René

    2016-05-01

    The hypothalamic peptide oxytocin (OXT) has been identified as a key modulator of pair-bonding in men, but its effects in women are still elusive. Moreover, there is substantial evidence that hormonal contraception (HC) influences partner preferences and sexual satisfaction, which constitute core domains of OXT function. We thus hypothesized that OXT effects on partner-related behavioral and neural responses could be significantly altered in women using HC. In this functional magnetic resonance imaging study involving 40 pair-bonded women, 21 of whom were using HC, we investigated whether a 24-IU nasal dose of OXT would modulate brain reward responses evoked by the romantic partner's face relative to the faces of familiar and unfamiliar people. Treatment with OXT increased the perceived attractiveness of the partner relative to other men, which was paralleled by elevated responses in reward-associated regions, including the nucleus accumbens. These effects of OXT were absent in women using HC. Our results confirm and extend previous findings in men that OXT interacts with the brain reward system to reinforce partner value representations, indicating a common OXT-dependent mechanism underlying partner attraction in both sexes. This mechanism may be disturbed in women using HC, suggesting that gonadal steroids could alter partner-specific OXT effects. PMID:26722017

  10. Venous hemodynamic changes in lower limb venous disease: the UIP consensus according to scientific evidence.

    Science.gov (United States)

    Lee, Byung B; Nicolaides, Andrew N; Myers, Kenneth; Meissner, Mark; Kalodiki, Evi; Allegra, Claudio; Antignani, Pier L; Bækgaard, Niels; Beach, Kirk; Belcaro, Giovanni; Black, Stephen; Blomgren, Lena; Bouskela, Eliete; Cappelli, Massimo; Caprini, Joseph; Carpentier, Patrick; Cavezzi, Attilio; Chastanet, Sylvain; Christenson, Jan T; Christopoulos, Demetris; Clarke, Heather; Davies, Alun; Demaeseneer, Marianne; Eklöf, Bo; Ermini, Stefano; Fernández, Fidel; Franceschi, Claude; Gasparis, Antonios; Geroulakos, George; Sergio, Gianesini; Giannoukas, Athanasios; Gloviczki, Peter; Huang, Ying; Ibegbuna, Veronica; Kakkos, Stavros K; Kistner, Robert; Kölbel, Tilo; Kurstjens, Ralph L; Labropoulos, Nicos; Laredo, James; Lattimer, Christopher R; Lugli, Marzia; Lurie, Fedor; Maleti, Oscar; Markovic, Jovan; Mendoza, Erika; Monedero, Javier L; Moneta, Gregory; Moore, Hayley; Morrison, Nick; Mosti, Giovanni; Nelzén, Olle; Obermayer, Alfred; Ogawa, Tomohiro; Parsi, Kurosh; Partsch, Hugo; Passariello, Fausto; Perrin, Michel L; Pittaluga, Paul; Raju, Seshadri; Ricci, Stefano; Rosales, Antonio; Scuderi, Angelo; Slagsvold, Carl E; Thurin, Anders; Urbanek, Tomasz; M VAN Rij, Andre; Vasquez, Michael; Wittens, Cees H; Zamboni, Paolo; Zimmet, Steven; Ezpeleta, Santiago Z

    2016-06-01

    There are excellent guidelines for clinicians to manage venous diseases but few reviews to assess their hemodynamic background. Hemodynamic concepts that evolved in the past have largely remained unchallenged in recent decades, perhaps due to their often complicated nature and in part due to emergence of new diagnostic techniques. Duplex ultrasound scanning and other imaging techniques which evolved in the latter part of the 20th century have dominated investigation. They have greatly improved our understanding of the anatomical patterns of venous reflux and obstruction. However, they do not provide the physiological basis for understanding the hemodynamics of flow, pressure, compliance and resistance. Hemodynamic investigations appear to provide a better correlation with post-treatment clinical outcome and quality of life than ultrasound findings. There is a far better prospect for understanding the complete picture of the patient's disability and response to management by combining ultrasound with hemodynamic studies. Accordingly, at the instigation of Dr Angelo Scuderi, the Union Internationale de Phlebologie (UIP) executive board commissioned a large number of experts to assess all aspects of management for venous disease by evidence-based principles. These included experts from various member societies including the European Venous Forum (EVF), American Venous Forum (AVF), American College of Phlebology (ACP) and Cardiovascular Disease Educational and Research Trust (CDERT). Their aim was to confirm or dispel long-held hemodynamic principles and to provide a comprehensive review of venous hemodynamic concepts underlying the pathophysiology of lower limb venous disorders, their usefulness for investigating patients and the relevant hemodynamic changes associated with various forms of treatment. Chapter 1 is devoted to basic hemodynamic concepts and normal venous physiology. Chapter 2 presents the mechanism and magnitude of hemodynamic changes in acute deep vein

  11. Cerebral metabolic and hemodynamic effects of sensory and cognitive stimuli in normal subjects

    International Nuclear Information System (INIS)

    The development of the 18-F-fluorodeoxyglucose and the 11-C-deoxyglucose et al., techniques for the determination of local cerebral glucose metabolism in humans has made it possible to examine the regional effects of sensory and cognitive stimuli on the brain. By mapping the regional metabolic or hemodynamic alterations produced by these stimuli it is possible to infer which regions of the brain are involved in the processing of that information. Much data has accumulated in the literature which supports this concept of a close link between the functional state of a region of the brain and its metabolic rate, and secondarily its blood flow

  12. Leptin Is Associated With Exaggerated Brain Reward and Emotion Responses to Food Images in Adolescent Obesity

    OpenAIRE

    Jastreboff, Ania M.; Lacadie, Cheryl; Seo, Dongju; Kubat, Jessica; Van Name, Michelle A.; Giannini, Cosimo; Savoye, Mary; Constable, R. Todd; Sherwin, Robert S.; Caprio, Sonia; Sinha, Rajita

    2014-01-01

    OBJECTIVE In the U.S., an astonishing 12.5 million children and adolescents are now obese, predisposing 17% of our nation’s youth to metabolic complications of obesity, such as type 2 diabetes (T2D). Adolescent obesity has tripled over the last three decades in the setting of food advertising directed at children. Obese adults exhibit increased brain responses to food images in motivation-reward pathways. These neural alterations may be attributed to obesity-related metabolic changes, which p...

  13. Global brain blood-oxygen level responses to autonomic challenges in obstructive sleep apnea.

    Directory of Open Access Journals (Sweden)

    Paul M Macey

    Full Text Available Obstructive sleep apnea (OSA is accompanied by brain injury, perhaps resulting from apnea-related hypoxia or periods of impaired cerebral perfusion. Perfusion changes can be determined indirectly by evaluation of cerebral blood volume and oxygenation alterations, which can be measured rapidly and non-invasively with the global blood oxygen level dependent (BOLD signal, a magnetic resonance imaging procedure. We assessed acute BOLD responses in OSA subjects to pressor challenges that elicit cerebral blood flow changes, using a two-group comparative design with healthy subjects as a reference. We separately assessed female and male patterns, since OSA characteristics and brain injury differ between sexes. We studied 94 subjects, 37 with newly-diagnosed, untreated OSA (6 female (age mean ± std: 52.1±8.1 yrs; apnea/hypopnea index [AHI]: 27.7±15.6 events/hr and 31 male 54.3±8.4 yrs; AHI: 37.4±19.6 events/hr, and 20 female (age 50.5±8.1 yrs and 37 male (age 45.6±9.2 yrs healthy control subjects. We measured brain BOLD responses every 2 s while subjects underwent cold pressor, hand grip, and Valsalva maneuver challenges. The global BOLD signal rapidly changed after the first 2 s of each challenge, and differed in magnitude between groups to two challenges (cold pressor, hand grip, but not to the Valsalva maneuver (repeated measures ANOVA, p<0.05. OSA females showed greater differences from males in response magnitude and pattern, relative to healthy counterparts. Cold pressor BOLD signal increases (mean ± adjusted standard error at the 8 s peak were: OSA 0.14±0.08% vs. Control 0.31±0.06%, and hand grip at 6 s were: OSA 0.08±0.03% vs. Control at 0.30±0.02%. These findings, indicative of reduced cerebral blood flow changes to autonomic challenges in OSA, complement earlier reports of altered resting blood flow and reduced cerebral artery responsiveness. Females are more affected than males, an outcome which may contribute to the sex

  14. Selective alignment of brain responses by task demands during semantic processing.

    Science.gov (United States)

    Baggio, Giosuè

    2012-04-01

    The way the brain binds together words to form sentences may depend on whether and how the arising cognitive representation is to be used in behavior. The amplitude of the N400 effect in event-related brain potentials is inversely correlated with the degree of fit of a word's meaning into a semantic representation of the preceding discourse. This study reports a double dissociation in the latency characteristics of the N400 effect depending on task demands. When participants silently read words in a sentence context, without issuing a relevant overt response, greater temporal alignment over recording sites occurs for N400 onsets than peaks. If however a behavior is produced - here pressing a button in a binary probe selection task - exactly the opposite pattern is observed, with stronger alignment of N400 peaks than onsets. The peak amplitude of the N400 effect correlates best with the latency characteristic showing less temporal dispersion. These findings suggest that meaning construction in the brain is subtly affected by task demands, and that there is complex functional integration between semantic combinatorics and control systems handling behavioral goals. PMID:22245013

  15. Killing of Brain Tumor Cells by Hypoxia-Responsive Element Mediated Expression of BAX1

    Science.gov (United States)

    Ruan, Hangjun; Wang, Jingli; Hu, Lily; Lin, Ching-Shwun; Lamborn, Kathleen R; Deen, Dennis F

    1999-01-01

    Abstract The presence of radioresistant hypoxic cells in human brain tumors limits the overall effectiveness of conventional fractionated radiation therapy. Tumor-specific therapies that target hypoxic cells are clearly needed. We have investigated the expression of suicide genes under hypoxia by a hypoxia-responsive element (HRE), which can be activated through hypoxia-inducible factor-1 (HIF-1). We transfected plasmids containing multiple copies of HRE into U-87 MG and U-251 MG-NCI human brain tumor cells and tested their ability to induce LacZ gene expression under anoxia. Gene expression under anoxia versus oxia was increased about 12-fold for U-87 MG cells and about fourfold for U-251 MG-NCI cells. At intermediate hypoxic conditions, increased LacZ gene expression in U-87 MG cells was induced by the plasmid that contained three HREs, but not by the plasmid with two HREs. Lastly, when we placed a suicide gene BAX under the control of HREs, cells transfected with the BAX plasmids were preferentially killed through apoptosis under anoxia. Our studies demonstrate that HRE-regulated gene expression is active in brain tumor cells, and that the amount of increased gene expression obtained is dependent on the cell line, the HRE copy number, and the degree of hypoxia. PMID:10933058

  16. Killing of Brain Tumor Cells by Hypoxia-Responsive Element Mediated Expression of BAX

    Directory of Open Access Journals (Sweden)

    Hangjun Ruan

    1999-11-01

    Full Text Available The presence of radioresistant hypoxic cells in human brain tumors limits the overall effectiveness of conventional fractionated radiation therapy. Tumor-specific therapies that target hypoxic cells are clearly needed. We have investigated the expression of suicide genes under hypoxia by a hypoxia-responsive element (HRE, which can be activated through hypoxia-inducible factor-1 (HIF-1. We transfected plasmids containing multiple copies of HIRE into U-87 MG and U-251 MG-NCI human brain tumor cells and tested their ability to induce LacZ gene expression under anoxia. Gene expression under anoxia versus oxia was increased about 12-fold for U-87 MG cells and about fourfold for U-251 MG-NCI cells. At intermediate hypoxic conditions, increased LacZ gene expression in U-87 MG cells was induced by the plasmid that contained three HREs, but not by the plasmid with two HREs. Lastly, when we placed a suicide gene BAX under the control of HREs, cells transfected with the BAX plasmids were preferentially killed through apoptosis under anoxia. Our studies demonstrate that HRE-regulated gene expression is active in brain tumor cells, and that the amount of increased gene expression obtained is dependent on the cell line, the HIRE copy number, and the degree of hypoxia.

  17. Calcineurin β protects brain after injury by activating the unfolded protein response.

    Science.gov (United States)

    Chen, Yanan; Holstein, Deborah M; Aime, Sofia; Bollo, Mariana; Lechleiter, James D

    2016-10-01

    The Ca(2+)-dependent phosphatase, calcineurin (CN) is thought to play a detrimental role in damaged neurons; however, its role in astrocytes is unclear. In cultured astrocytes, CNβ expression increased after treatment with a sarco/endoplasmic reticulum Ca(2+)-ATPase inhibitor, thapsigargin, and with oxygen and glucose deprivation, an in vitro model of ischemia. Similarly, CNβ was induced in astrocytes in vivo in two different mouse models of brain injury - photothrombotic stroke and traumatic brain injury (TBI). Immunoprecipitation and chemical activation dimerization methods pointed to physical interaction of CNβ with the unfolded protein response (UPR) sensor, protein kinase RNA-like endoplasmic reticulum kinase (PERK). In accordance, induction of CNβ resulted in oligomerization and activation of PERK. Strikingly, the presence of a phosphatase inhibitor did not interfere with CNβ-mediated activation of PERK, suggesting a hitherto undiscovered non-enzymatic role for CNβ. Importantly, the cytoprotective function of CNβ was PERK-dependent both in vitro and in vivo. Loss of CNβ in vivo resulted in a significant increase in cerebral damage, and correlated with a decrease in astrocyte size, PERK activity and glial fibrillary acidic protein (GFAP) expression. Taken together, these data reveal a critical role for the CNβ-PERK axis in not only prolonging astrocyte cell survival but also in modulating astrogliosis after brain injury. PMID:27334877

  18. Pre-attentive modulation of brain responses to tones in coloured-hearing synesthetes

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    Jäncke Lutz

    2012-12-01

    Full Text Available Abstract Background Coloured-hearing (CH synesthesia is a perceptual phenomenon in which an acoustic stimulus (the inducer initiates a concurrent colour perception (the concurrent. Individuals with CH synesthesia "see" colours when hearing tones, words, or music; this specific phenomenon suggesting a close relationship between auditory and visual representations. To date, it is still unknown whether the perception of colours is associated with a modulation of brain functions in the inducing brain area, namely in the auditory-related cortex and associated brain areas. In addition, there is an on-going debate as to whether attention to the inducer is necessarily required for eliciting a visual concurrent, or whether the latter can emerge in a pre-attentive fashion. Results By using the EEG technique in the context of a pre-attentive mismatch negativity (MMN paradigm, we show that the binding of tones and colours in CH synesthetes is associated with increased MMN amplitudes in response to deviant tones supposed to induce novel concurrent colour perceptions. Most notably, the increased MMN amplitudes we revealed in the CH synesthetes were associated with stronger intracerebral current densities originating from the auditory cortex, parietal cortex, and ventral visual areas. Conclusions The automatic binding of tones and colours in CH synesthetes is accompanied by an early pre-attentive process recruiting the auditory cortex, inferior and superior parietal lobules, as well as ventral occipital areas.

  19. Brain responses in humans reveal ideal observer-like sensitivity to complex acoustic patterns.

    Science.gov (United States)

    Barascud, Nicolas; Pearce, Marcus T; Griffiths, Timothy D; Friston, Karl J; Chait, Maria

    2016-02-01

    We use behavioral methods, magnetoencephalography, and functional MRI to investigate how human listeners discover temporal patterns and statistical regularities in complex sound sequences. Sensitivity to patterns is fundamental to sensory processing, in particular in the auditory system, because most auditory signals only have meaning as successions over time. Previous evidence suggests that the brain is tuned to the statistics of sensory stimulation. However, the process through which this arises has been elusive. We demonstrate that listeners are remarkably sensitive to the emergence of complex patterns within rapidly evolving sound sequences, performing on par with an ideal observer model. Brain responses reveal online processes of evidence accumulation--dynamic changes in tonic activity precisely correlate with the expected precision or predictability of ongoing auditory input--both in terms of deterministic (first-order) structure and the entropy of random sequences. Source analysis demonstrates an interaction between primary auditory cortex, hippocampus, and inferior frontal gyrus in the process of discovering the regularity within the ongoing sound sequence. The results are consistent with precision based predictive coding accounts of perceptual inference and provide compelling neurophysiological evidence of the brain's capacity to encode high-order temporal structure in sensory signals. PMID:26787854

  20. Hemodynamic changes in depressive patients

    Institute of Scientific and Technical Information of China (English)

    MA Ying; LI Hui-chun; ZHENG Lei-lei; YU Hua-liang

    2006-01-01

    Objective: This study is aimed at exploring the relationship between hemodynamic changes and depressive and anxious symptom in depression patients. Methods: The cardiac function indices including the left stroke index (LSI), ejection fraction (EF), heart rate (HR), diastolic pressure mean (DPM), systolic pressure mean (SPM), left ventricle end-diastolic volume (LVDV), effective circulating volume (ECV), resistance total mean (RTM) and blood flow smooth degree (BFSD) were determined in 65 patients with major depressive disorders and 31 healthy normal controls. The clinical symptoms were assessed with Hamilton depression scale (HAMD) and Hamilton anxiety scale (HAMA). Results: In patients with depression without anxiety,LSI, EF, LVDV, DPM, SPM, ECV, BFSD were significantly lower than those in controls, while RTM was higher than that in controls. Patients with comorbidity of depression and anxiety showed decreased LVDV, ECV, BFSD, and increased HR in comparison with the controls. The anxiety/somatization factor score positively correlated with LSI, EF, LVDV, but negatively correlated with RTM. There was negative correlation between retardation factor score and DPM, SPM, LVDV. Conclusion: The study indicated that there are noticeable changes in left ventricle preload and afterload, blood pressure, peripheral resistance, and microcirculation in depressive patients, and that the accompanying anxiety makes the changes more complicated.

  1. Hemodynamics driven cardiac valve morphogenesis.

    Science.gov (United States)

    Steed, Emily; Boselli, Francesco; Vermot, Julien

    2016-07-01

    Mechanical forces are instrumental to cardiovascular development and physiology. The heart beats approximately 2.6 billion times in a human lifetime and heart valves ensure that these contractions result in an efficient, unidirectional flow of the blood. Composed of endocardial cells (EdCs) and extracellular matrix (ECM), cardiac valves are among the most mechanically challenged structures of the body both during and after their development. Understanding how hemodynamic forces modulate cardiovascular function and morphogenesis is key to unraveling the relationship between normal and pathological cardiovascular development and physiology. Most valve diseases have their origins in embryogenesis, either as signs of abnormal developmental processes or the aberrant re-expression of fetal gene programs normally quiescent in adulthood. Here we review recent discoveries in the mechanobiology of cardiac valve development and introduce the latest technologies being developed in the zebrafish, including live cell imaging and optical technologies, as well as modeling approaches that are currently transforming this field. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel. PMID:26608609

  2. Effect of skull flexural properties on brain response during dynamic head loading - biomed 2013.

    Science.gov (United States)

    Harrigan, T P; Roberts, J C; Ward, E E; Carneal, C M; Merkle, A C

    2013-01-01

    The skull-brain complex is typically modeled as an integrated structure, similar to a fluid-filled shell. Under dynamic loads, the interaction of the skull and the underlying brain, cerebrospinal fluid, and other tissue produces the pressure and strain histories that are the basis for many theories meant to describe the genesis of traumatic brain injury. In addition, local bone strains are of interest for predicting skull fracture in blunt trauma. However, the role of skull flexure in the intracranial pressure response to blunt trauma is complex. Since the relative time scales for pressure and flexural wave transmission across the skull are not easily separated, it is difficult to separate out the relative roles of the mechanical components in this system. This study uses a finite element model of the head, which is validated for pressure transmission to the brain, to assess the influence of skull table flexural stiffness on pressure in the brain and on strain within the skull. In a Human Head Finite Element Model, the skull component was modified by attaching shell elements to the inner and outer surfaces of the existing solid elements that modeled the skull. The shell elements were given the properties of bone, and the existing solid elements were decreased so that the overall stiffness along the surface of the skull was unchanged, but the skull table bending stiffness increased by a factor of 2.4. Blunt impact loads were applied to the frontal bone centrally, using LS-Dyna. The intracranial pressure predictions and the strain predictions in the skull were compared for models with and without surface shell elements, showing that the pressures in the mid-anterior and mid-posterior of the brain were very similar, but the strains in the skull under the loads and adjacent to the loads were decreased 15% with stiffer flexural properties. Pressure equilibration to nearly hydrostatic distributions occurred, indicating that the important frequency components for typical

  3. Prevention of hemodynamic and vascular albumin filtration changes in diabetic rats by aldose reductase inhibitors

    International Nuclear Information System (INIS)

    This study investigated hemodynamic changes in diabetic rats and their relationship to changes in vascular albumin permeation and increased metabolism of glucose to sorbitol. The effects of 6 wk of streptozocin-induced diabetes and three structurally different inhibitors of aldose reductase were examined on (1) regional blood flow (assessed with 15-microns 85Sr-labeled microspheres) and vascular permeation by 125I-labeled bovine serum albumin (BSA) and (2) glomerular filtration rate (assessed by plasma clearance of 57Co-labeled EDTA) and urinary albumin excretion (determined by radial immunodiffusion assay). In diabetic rats, blood flow was significantly increased in ocular tissues (anterior uvea, posterior uvea, retina, and optic nerve), sciatic nerve, kidney, new granulation tissue, cecum, and brain. 125I-BSA permeation was increased in all of these tissues except brain. Glomerular filtration rate and 24-h urinary albumin excretion were increased 2- and 29-fold, respectively, in diabetic rats. All three aldose reductase inhibitors completely prevented or markedly reduced these hemodynamic and vascular filtration changes and increases in tissue sorbitol levels in the anterior uvea, posterior uvea, retina, sciatic nerve, and granulation tissue. These observations indicate that early diabetes-induced hemodynamic changes and increased vascular albumin permeation and urinary albumin excretion are aldose reductase-linked phenomena. Discordant effects of aldose reductase inhibitors on blood flow and vascular albumin permeation in some tissues suggest that increased vascular albumin permeation is not entirely attributable to hemodynamic change

  4. CADrx for GBM Brain Tumors: Predicting Treatment Response from Changes in Diffusion-Weighted MRI

    Directory of Open Access Journals (Sweden)

    Matthew S. Brown

    2009-11-01

    Full Text Available The goal of this study was to develop a computer-aided therapeutic response (CADrx system for early prediction of drug treatment response for glioblastoma multiforme (GBM brain tumors with diffusion weighted (DW MR images. In conventional Macdonald assessment, tumor response is assessed nine weeks or more post-treatment. However, we will investigate the ability of DW-MRI to assess response earlier, at five weeks post treatment. The apparent diffusion coefficient (ADC map, calculated from DW images, has been shown to reveal changes in the tumor’s microenvironment preceding morphologic tumor changes. ADC values in treated brain tumors could theoretically both increase due to the cell kill (and thus reduced cell density and decrease due to inhibition of edema. In this study, we investigated the effectiveness of features that quantify changes from pre- and post-treatment tumor ADC histograms to detect treatment response. There are three parts to this study: first, tumor regions were segmented on T1w contrast enhanced images by Otsu’s thresholding method, and mapped from T1w images onto ADC images by a 3D region of interest (ROI mapping tool using DICOM header information; second, ADC histograms of the tumor region were extracted from both pre- and five weeks post-treatment scans, and fitted by a two-component Gaussian mixture model (GMM. The GMM features as well as standard histogram-based features were extracted. Finally, supervised machine learning techniques were applied for classification of responders or non-responders. The approach was evaluated with a dataset of 85 patients with GBM under chemotherapy, in which 39 responded and 46 did not, based on tumor volume reduction. We compared adaBoost, random forest and support vector machine classification algorithms, using ten-fold cross validation, resulting in the best accuracy of 69.41% and the corresponding area under the curve (Az of 0.70.

  5. Predictive value of brain perfusion SPECT for rTMS response in pharmacoresistant depression

    Energy Technology Data Exchange (ETDEWEB)

    Richieri, Raphaelle; Lancon, Christophe [Sainte-Marguerite University Hospital, Department of Psychiatry, Marseille (France); La Timone University, EA 3279 - Self-perceived Health Assessment Research Unit, School of Medicine, Marseille (France); Boyer, Laurent [La Timone University, EA 3279 - Self-perceived Health Assessment Research Unit, School of Medicine, Marseille (France); La Timone University Hospital, Assistance Publique - Hopitaux de Marseille, Department of Public Health, Marseille (France); Farisse, Jean [Sainte-Marguerite University Hospital, Department of Psychiatry, Marseille (France); Colavolpe, Cecile; Mundler, Olivier [La Timone University Hospital, Assistance Publique - Hopitaux de Marseille, Service Central de Biophysique et Medecine Nucleaire, Marseille (France); Universite de la Mediterranee, Centre Europeen de Recherche en Imagerie Medicale (CERIMED), Marseille (France); Guedj, Eric [La Timone University Hospital, Assistance Publique - Hopitaux de Marseille, Service Central de Biophysique et Medecine Nucleaire, Marseille (France); Universite de la Mediterranee, Centre Europeen de Recherche en Imagerie Medicale (CERIMED), Marseille (France); Hopital de la Timone, Service Central de Biophysique et de Medecine Nucleaire, Marseille Cedex 5 (France)

    2011-09-15

    The aim of this study was to determine the predictive value of whole-brain voxel-based regional cerebral blood flow (rCBF) for repetitive transcranial magnetic stimulation (rTMS) response in patients with pharmacoresistant depression. Thirty-three right-handed patients who met DSM-IV criteria for major depressive disorder (unipolar or bipolar depression) were included before rTMS. rTMS response was defined as at least 50% reduction in the baseline Beck Depression Inventory scores. The predictive value of {sup 99m}Tc-ethyl cysteinate dimer (ECD) single photon emission computed tomography (SPECT) for rTMS response was studied before treatment by comparing rTMS responders to non-responders at voxel level using Statistical Parametric Mapping (SPM) (p < 0.001, uncorrected). Of the patients, 18 (54.5%) were responders to rTMS and 15 were non-responders (45.5%). There were no statistically significant differences in demographic and clinical characteristics (p > 0.10). In comparison to responders, non-responders showed significant hypoperfusions (p < 0.001, uncorrected) in the left medial and bilateral superior frontal cortices (BA10), the left uncus/parahippocampal cortex (BA20/BA35) and the right thalamus. The area under the curve for the combination of SPECT clusters to predict rTMS response was 0.89 (p < 0.001). Sensitivity, specificity, positive predictive value and negative predictive value for the combination of clusters were: 94, 73, 81 and 92%, respectively. This study shows that, in pharmacoresistant depression, pretreatment rCBF of specific brain regions is a strong predictor for response to rTMS in patients with homogeneous demographic/clinical features. (orig.)

  6. Deep brain stimulation and responsiveness of the Persian version of Parkinson's disease questionnaire with 39-items.

    Directory of Open Access Journals (Sweden)

    Gholam Ali Shahidi

    2014-12-01

    Full Text Available Assessment of quality-of-life (QOF as an outcome measure after deep brain stimulation (DBS surgery in patients with Parkinson's disease (PD need a valid, reliable and responsive instrument. The aim of the current study was to determine responsiveness of validated Persian version of PD questionnaire with 39-items (PDQ-39 after DBS surgery in patients with PD.Eleven patients with PD, who were candidate for DBS operation between May 2012 and June 2013 were assessed. PDQ-39 and short-form questionnaire with 36-items (SF-36 were used. To assess responsiveness of PDQ-39 standardized response mean (SRM was used.Mean age was 51.8 (8.8 and all of the patients, but just one were male (10 patients. Mean duration of the disease was 8.7 (2.1 years. Eight patients were categorized as moderate using Hoehn and Yahr (H and Y classification. All patients had a better H and Y score compared with the baseline evaluation (3.09 vs. 0.79. The amount of SRM was above 0.70 for all domains means a large responsiveness for PDQ-39.Persian version of PDQ-39 has an acceptable responsiveness and could be used to assess as an outcome measure to evaluate the effect of therapies on PD.

  7. Titanium oxide (TiO2) nanoparticles in induction of apoptosis and inflammatory response in brain

    International Nuclear Information System (INIS)

    The ever increasing applications of engineered nanoparticles in 21st century cause serious concern about its potential health risks on living being. Regulatory health risk assessment of such particles has become mandatory for the safe use of nanomaterials in consumer products and medicines. In order to study the mechanism underlying the effects of nano-TiO2 (TiO2 nanoparticles) on the brain, wistar rats were administrated intravenously with various doses of nano-TiO2 (21 nm) through the caudal vein, once a week for 4 weeks and different parameters such as bioaccumulation of nano-TiO2, oxidative stress-mediated response, level of inflammatory markers such as NF-κB (p65), HSP 60, p38, nitric oxide, IFN-γ and TNF-α, and level of neurochemicals in brain as well as DNA damage and expression of apoptosis markers (p53, Bax, Bcl-2, and cyto c) were evaluated. Results show that the concentration of nano-TiO2 in the brain increased with increasing the doses of nano-TiO2. Oxidative stress and injury of the brain occurred as nano-TiO2 appeared to trigger a cascade of reactions such as inflammation, lipid peroxidation, decreases the activities of antioxidative enzymes and melatonin level, the reduction of glutamic acid, downregulated levels of acetylcholinesterase activities, and the increase in caspase-3 activity (a biomarker of apoptosis), DNA fragmentation, and apoptosis. It may be concluded that nano-TiO2 induces oxidative stress that leads to activation of inflammatory cytokines and an alteration in the level of neurotransmitters resulted in the induction of mitochondrial-mediated apoptosis

  8. Nearly Complete Response of Brain Metastases from HER2 Overexpressing Breast Cancer with Lapatinib and Capecitabine after Whole Brain Irradiation

    Directory of Open Access Journals (Sweden)

    Esin Oktay

    2013-01-01

    Full Text Available Trastuzumab treatment does not prevent intracranial seeding and is largely ineffective for established central nervous system metastasis in HER2 overexpressing breast cancer patients. Combination therapy of lapatinib and capecitabine may be an effective treatment option for brain metastasis of HER2-positive breast cancer. We report a patient with breast cancer overexpressing HER-2 where brain metastases were successfully treated with radiation and a combination of lapatinib and capecitabine.

  9. Dehydration, hemodynamics and fluid volume optimization after induction of general anesthesia

    OpenAIRE

    Yuhong Li; Rui He; Xiaojiang Ying; Robert G. Hahn

    2014-01-01

    OBJECTIVES: Fluid volume optimization guided by stroke volume measurements reduces complications of colorectal and high-risk surgeries. We studied whether dehydration or a strong hemodynamic response to general anesthesia increases the probability of fluid responsiveness before surgery begins. METHODS: Cardiac output, stroke volu...

  10. Electrical brain responses in language-impaired children reveal grammar-specific deficits.

    Directory of Open Access Journals (Sweden)

    Elisabeth Fonteneau

    Full Text Available BACKGROUND: Scientific and public fascination with human language have included intensive scrutiny of language disorders as a new window onto the biological foundations of language and its evolutionary origins. Specific language impairment (SLI, which affects over 7% of children, is one such disorder. SLI has received robust scientific attention, in part because of its recent linkage to a specific gene and loci on chromosomes and in part because of the prevailing question regarding the scope of its language impairment: Does the disorder impact the general ability to segment and process language or a specific ability to compute grammar? Here we provide novel electrophysiological data showing a domain-specific deficit within the grammar of language that has been hitherto undetectable through behavioural data alone. METHODS AND FINDINGS: We presented participants with Grammatical(G-SLI, age-matched controls, and younger child and adult controls, with questions containing syntactic violations and sentences containing semantic violations. Electrophysiological brain responses revealed a selective impairment to only neural circuitry that is specific to grammatical processing in G-SLI. Furthermore, the participants with G-SLI appeared to be partially compensating for their syntactic deficit by using neural circuitry associated with semantic processing and all non-grammar-specific and low-level auditory neural responses were normal. CONCLUSIONS: The findings indicate that grammatical neural circuitry underlying language is a developmentally unique system in the functional architecture of the brain, and this complex higher cognitive system can be selectively impaired. The findings advance fundamental understanding about how cognitive systems develop and all human language is represented and processed in the brain.

  11. Physical attractiveness and sex as modulatory factors of empathic brain responses to pain

    Directory of Open Access Journals (Sweden)

    Kamila Jankowiak Siuda

    2015-09-01

    Full Text Available Empathy is a process that comprises affective sharing, imagining, and understanding the emotions and mental states of others. The brain structures involved in empathy for physical pain include the anterior insula (AI, and the anterior cingulate cortex (ACC. High empathy may lead people to undertake pro-social behaviour. It is important to understand how this process can be changed, and what factors these empathic responses depend on. Physical attractiveness is a major social and evolutional cue, playing a role in the formation of interpersonal evaluation. The aim of the study was to determine how attractiveness affects the level of empathy both in relation to self-rated behaviour and in terms of activation of specific empathy-related brain regions. Twenty-seven subjects (14 female and 13 male were studied using fMRI method while they were watching short video scenes involving physically more and less attractive men and women who exhibited pain responses. In the absence of behavioural effects in compassion ratings, we observed stronger activation in empathic brain structures (ACC; AI for less attractive men and for attractive women than for attractive men. Evolutionary psychology studies suggest that beauty is valued more highly in females than males, which might lead observers to empathize more strongly with the attractive woman than the men. Attractive mens’ faces are typically associated with enhanced masculine facial characteristics and are considered to possess fewer desirable personality traits compared with feminized faces. This could explain why more empathy was shown to less attractive men. In conclusion, the study showed that the attractiveness and sex of a model are important modulators of empathy for pain.

  12. Physical attractiveness and sex as modulatory factors of empathic brain responses to pain.

    Science.gov (United States)

    Jankowiak-Siuda, Kamila; Rymarczyk, Krystyna; Żurawski, Łukasz; Jednoróg, Katarzyna; Marchewka, Artur

    2015-01-01

    Empathy is a process that comprises affective sharing, imagining, and understanding the emotions and mental states of others. The brain structures involved in empathy for physical pain include the anterior insula (AI), and the anterior cingulate cortex (ACC). High empathy may lead people to undertake pro-social behavior. It is important to understand how this process can be changed, and what factors these empathic responses depend on. Physical attractiveness is a major social and evolutional cue, playing a role in the formation of interpersonal evaluation. The aim of the study was to determine how attractiveness affects the level of empathy both in relation to self-rated behavior and in terms of activation of specific empathy-related brain regions. Twenty-seven subjects (14 female and 13 male) were studied using functional magnetic resonance imaging (fMRI) method while they were watching short video scenes involving physically more and less attractive men and women who exhibited pain responses. In the absence of behavioral effects in compassion ratings, we observed stronger activation in empathic brain structures (ACC; AI) for less attractive men and for attractive women than for attractive men. Evolutionary psychology studies suggest that beauty is valued more highly in females than males, which might lead observers to empathize more strongly with the attractive woman than the men. Attractive mens' faces are typically associated with enhanced masculine facial characteristics and are considered to possess fewer desirable personality traits compared with feminized faces. This could explain why more empathy was shown to less attractive men. In conclusion, the study showed that the attractiveness and sex of a model are important modulators of empathy for pain. PMID:26441569

  13. Estimation of brain activation in response to major and minor scales by fMRI

    International Nuclear Information System (INIS)

    We made fMRI measurements of the brain responses to major and minor scales which are the fundamental elements for making melodies in music. In addition, we used an arpeggio of diminished 7th. For a control stimulus, we provided a sequence of repeated single tones. The ascending scales of 12 major and 12 minor keys were made starting from F no.3 to F4. Each scale was 3 s in duration. A 3 s scan was performed 2-3 s (randomized) after a scale has been finished and repeated every 14 s (sparse time scanning). Typically, major scales activated the left inferior frontal gyrus, minor scales the posterior cingulate gyrus and the diminished arpeggio the left auditory cortex. In general, the left hemisphere was more activated than usually seen in responses to music. (author)

  14. The brain response to peripheral insulin declines with age: a contribution of the blood-brain barrier?

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    Tina Sartorius

    Full Text Available It is a matter of debate whether impaired insulin action originates from a defect at the neural level or impaired transport of the hormone into the brain. In this study, we aimed to investigate the effect of aging on insulin concentrations in the periphery and the central nervous system as well as its impact on insulin-dependent brain activity.Insulin, glucose and albumin concentrations were determined in 160 paired human serum and cerebrospinal fluid (CSF samples. Additionally, insulin was applied in young and aged mice by subcutaneous injection or intracerebroventricularly to circumvent the blood-brain barrier. Insulin action and cortical activity were assessed by Western blotting and electrocorticography radiotelemetric measurements.In humans, CSF glucose and insulin concentrations were tightly correlated with the respective serum/plasma concentrations. The CSF/serum ratio for insulin was reduced in older subjects while the CSF/serum ratio for albumin increased with age like for most other proteins. Western blot analysis in murine whole brain lysates revealed impaired phosphorylation of AKT (P-AKT in aged mice following peripheral insulin stimulation whereas P-AKT was comparable to levels in young mice after intracerebroventricular insulin application. As readout for insulin action in the brain, insulin-mediated cortical brain activity instantly increased in young mice subcutaneously injected with insulin but was significantly reduced and delayed in aged mice during the treatment period. When insulin was applied intracerebroventricularly into aged animals, brain activity was readily improved.This study discloses age-dependent changes in insulin CSF/serum ratios in humans. In the elderly, cerebral insulin resistance might be partially attributed to an impaired transport of insulin into the central nervous system.

  15. Effects of unexpected chords and of performer's expression on brain responses and electrodermal activity.

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    Stefan Koelsch

    Full Text Available BACKGROUND: There is lack of neuroscientific studies investigating music processing with naturalistic stimuli, and brain responses to real music are, thus, largely unknown. METHODOLOGY/PRINCIPAL FINDINGS: This study investigates event-related brain potentials (ERPs, skin conductance responses (SCRs and heart rate (HR elicited by unexpected chords of piano sonatas as they were originally arranged by composers, and as they were played by professional pianists. From the musical excerpts played by the pianists (with emotional expression, we also created versions without variations in tempo and loudness (without musical expression to investigate effects of musical expression on ERPs and SCRs. Compared to expected chords, unexpected chords elicited an early right anterior negativity (ERAN, reflecting music-syntactic processing and an N5 (reflecting processing of meaning information in the ERPs, as well as clear changes in the SCRs (reflecting that unexpected chords also elicited emotional responses. The ERAN was not influenced by emotional expression, whereas N5 potentials elicited by chords in general (regardless of their chord function differed between the expressive and the non-expressive condition. CONCLUSIONS/SIGNIFICANCE: These results show that the neural mechanisms of music-syntactic processing operate independently of the emotional qualities of a stimulus, justifying the use of stimuli without emotional expression to investigate the cognitive processing of musical structure. Moreover, the data indicate that musical expression affects the neural mechanisms underlying the processing of musical meaning. Our data are the first to reveal influences of musical performance on ERPs and SCRs, and to show physiological responses to unexpected chords in naturalistic music.

  16. Multisensory stimuli elicit altered oscillatory brain responses at gamma frequencies in patients with schizophrenia

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    David B. Stone

    2014-11-01

    Full Text Available Deficits in auditory and visual unisensory responses are well documented in patients with schizophrenia; however, potential abnormalities elicited from multisensory audio-visual stimuli are less understood. Further, schizophrenia patients have shown abnormal patterns in task-related and task-independent oscillatory brain activity, particularly in the gamma frequency band. We examined oscillatory responses to basic unisensory and multisensory stimuli in schizophrenia patients (N = 46 and healthy controls (N = 57 using magnetoencephalography (MEG. Time-frequency decomposition was performed to determine regions of significant changes in gamma band power by group in response to unisensory and multisensory stimuli relative to baseline levels. Results showed significant behavioral differences between groups in response to unisensory and multisensory stimuli. In addition, time-frequency analysis revealed significant decreases and increases in gamma-band power in schizophrenia patients relative to healthy controls, which emerged both early and late over both sensory and frontal regions in response to unisensory and multisensory stimuli. Unisensory gamma-band power predicted multisensory gamma-band power differently by group. Furthermore, gamma-band power in these regions predicted performance in select measures of the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS test battery differently by group. These results reveal a unique pattern of task-related gamma-band power in schizophrenia patients relative to controls that may indicate reduced inhibition in combination with impaired oscillatory mechanisms in patients with schizophrenia.

  17. The Acute Inflammatory Response in Trauma/Hemorrhage and Traumatic Brain Injury : Current State and Emerging Prospects

    NARCIS (Netherlands)

    Namas, R.; Ghuma, A.; Hermus, L.; Zamora, R.; Okonkwo, D. O.; Billiar, T. R.; Vodovotz, Y.

    2009-01-01

    Traumatic injury/hemorrhagic shock (T/HS) elicits an acute inflammatory response that may result in death. Inflammation describes a coordinated series of molecular, cellular, tissue, organ, and systemic responses that drive the pathology of various diseases including T/HS and traumatic brain injury

  18. The effect of conditional probability of chord progression on brain response: an MEG study.

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    Seung-Goo Kim

    Full Text Available BACKGROUND: Recent electrophysiological and neuroimaging studies have explored how and where musical syntax in Western music is processed in the human brain. An inappropriate chord progression elicits an event-related potential (ERP component called an early right anterior negativity (ERAN or simply an early anterior negativity (EAN in an early stage of processing the musical syntax. Though the possible underlying mechanism of the EAN is assumed to be probabilistic learning, the effect of the probability of chord progressions on the EAN response has not been previously explored explicitly. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, the empirical conditional probabilities in a Western music corpus were employed as an approximation of the frequencies in previous exposure of participants. Three types of chord progression were presented to musicians and non-musicians in order to examine the correlation between the probability of chord progression and the neuromagnetic response using magnetoencephalography (MEG. Chord progressions were found to elicit early responses in a negatively correlating fashion with the conditional probability. Observed EANm (as a magnetic counterpart of the EAN component responses were consistent with the previously reported EAN responses in terms of latency and location. The effect of conditional probability interacted with the effect of musical training. In addition, the neural response also correlated with the behavioral measures in the non-musicians. CONCLUSIONS/SIGNIFICANCE: Our study is the first to reveal the correlation between the probability of chord progression and the corresponding neuromagnetic response. The current results suggest that the physiological response is a reflection of the probabilistic representations of the musical syntax. Moreover, the results indicate that the probabilistic representation is related to the musical training as well as the sensitivity of an individual.

  19. Computational Hemodynamic Simulation of Human Circulatory System under Altered Gravity

    Science.gov (United States)

    Kim. Chang Sung; Kiris, Cetin; Kwak, Dochan

    2003-01-01

    A computational hemodynamics approach is presented to simulate the blood flow through the human circulatory system under altered gravity conditions. Numerical techniques relevant to hemodynamics issues are introduced to non-Newtonian modeling for flow characteristics governed by red blood cells, distensible wall motion due to the heart pulse, and capillary bed modeling for outflow boundary conditions. Gravitational body force terms are added to the Navier-Stokes equations to study the effects of gravity on internal flows. Six-type gravity benchmark problems are originally presented to provide the fundamental understanding of gravitational effects on the human circulatory system. For code validation, computed results are compared with steady and unsteady experimental data for non-Newtonian flows in a carotid bifurcation model and a curved circular tube, respectively. This computational approach is then applied to the blood circulation in the human brain as a target problem. A three-dimensional, idealized Circle of Willis configuration is developed with minor arteries truncated based on anatomical data. Demonstrated is not only the mechanism of the collateral circulation but also the effects of gravity on the distensible wall motion and resultant flow patterns.

  20. Zinc or copper deficiency-induced impaired inflammatory response to brain trauma may be caused by the concomitant metallothionein changes

    DEFF Research Database (Denmark)

    Penkowa, Milena; Giralt, M.; Thomsen, Pernille Sjølin;

    2001-01-01

    The role of zinc- and copper-deficient diets on the inflammatory response to traumatic brain injury (TBI) has been evaluated in adult rats. As expected, zinc deficiency decreased food intake and body weight gain, and the latter effect was higher than that observed in pair-fed rats. In noninjured...... brains, zinc deficiency only affected significantly lectin (increasing) and glial fibrillary acidic protein (GFAP) and Cu,Zn-superoxide dismutase (Cu,Zn-SOD) (decreasing) immunoreactivities (irs). In injured brains, a profound gliosis was observed in the area surrounding the lesion, along with severe...... damage to neurons as indicated by neuron specific enolase (NSE) ir, and the number of cells undergoing apoptosis (measured by TUNEL) was dramatically increased. Zinc deficiency significantly altered brain response to TBI, potentiating the microgliosis and reducing the astrogliosis, while increasing the...

  1. Neuroinflammatory responses to traumatic brain injury: etiology, clinical consequences, and therapeutic opportunities

    Directory of Open Access Journals (Sweden)

    Lozano D

    2015-01-01

    Full Text Available Diego Lozano,* Gabriel S Gonzales-Portillo,* Sandra Acosta, Ike de la Pena, Naoki Tajiri, Yuji Kaneko, Cesar V Borlongan Department of Neurosurgery and Brain Repair, University of South Florida Morsani College of Medicine, Tampa, FL, USA *These authors contributed equally to this work Abstract: Traumatic brain injury (TBI is a serious public health problem accounting for 1.4 million emergency room visits by US citizens each year. Although TBI has been traditionally considered an acute injury, chronic symptoms reminiscent of neurodegenerative disorders have now been recognized. These progressive neurodegenerative-like symptoms manifest as impaired motor and cognitive skills, as well as stress, anxiety, and mood affective behavioral alterations. TBI, characterized by external bumps or blows to the head exceeding the brain’s protective capacity, causes physical damage to the central nervous system with accompanying neurological dysfunctions. The primary impact results in direct neural cell loss predominantly exhibiting necrotic death, which is then followed by a wave of secondary injury cascades including excitotoxicity, oxidative stress, mitochondrial dysfunction, blood–brain barrier disruption, and inflammation. All these processes exacerbate the damage, worsen the clinical outcomes, and persist as an evolving pathological hallmark of what we now describe as chronic TBI. Neuroinflammation in the acute stage of TBI mobilizes immune cells, astrocytes, cytokines, and chemokines toward the site of injury to mount an antiinflammatory response against brain damage; however, in the chronic stage, excess activation of these inflammatory elements contributes to an “inflamed” brain microenvironment that principally contributes to secondary cell death in TBI. Modulating these inflammatory cells by changing their phenotype from proinflammatory to antiinflammatory would likely promote therapeutic effects on TBI. Because neuroinflammation occurs at

  2. STAT1 signaling modulates HIV-1–induced inflammatory responses and leukocyte transmigration across the blood-brain barrier

    OpenAIRE

    Chaudhuri, Anathbandhu; Yang, Bo; Gendelman, Howard E; Persidsky, Yuri; Kanmogne, Georgette D.

    2008-01-01

    The relationship among neuroinflammation, blood-brain barrier (BBB) dysfunction, and progressive HIV-1 infection as they affect the onset and development of neuroAIDS is incompletely understood. One possible link is signal transducers and activators of transcription (STATs) pathways. These respond to proinflammatory and regulatory factors and could affect neuroinflammatory responses induced from infected cells and disease-affected brain tissue. Our previous works demonstrated that HIV-1 activ...

  3. Hemodynamic correlates of visuomotor motor adaptation by functional Near Infrared Spectroscopy.

    Science.gov (United States)

    Gentili, Rodolphe J; Hadavi, Cyrus; Ayaz, Hasan; Shewokis, Patricia A; Contreras-Vidal, Jose L

    2010-01-01

    The development of rehabilitation engineering technologies such as the design of smart prosthetics necessitates a deep understanding of brain mechanisms engaged in ecological situations when human interact with new tools and/or environments. Thus, we aimed to investigate potential hemodynamic signatures reflecting the level of cognitive-motor performance and/or the internal or mental states of individuals when learning a novel tool with unknown properties. These markers were derived from functional Near Infrared Spectroscopy (fNIR) signals. Our results indicate an increased level of oxy-hemoglobin in prefrontal sensors associated with enhanced kinematics during early compared with late learning. This is consistent with previous neuroimaging studies that revealed a higher contribution of prefrontal areas during early compare to late adaptation learning. These non-invasive functional hemodynamic markers may play a role in bioengineering applications such as smart neuroprosthesis and brain monitoring where adaptive behavior is important. PMID:21095985

  4. Brain responses to nouns, verbs and class-ambiguous words in context.

    Science.gov (United States)

    Federmeier, K D; Segal, J B; Lombrozo, T; Kutas, M

    2000-12-01

    Recent neuropsychological and imaging data have implicated different brain networks in the processing of different word classes, nouns being linked primarily to posterior, visual object-processing regions and verbs to frontal, motor-processing areas. However, as most of these studies have examined words in isolation, the consequences of such anatomically based representational differences, if any, for the processing of these items in sentences remains unclear. Additionally, in some languages many words (e.g. 'drink') are class-ambiguous, i.e. they can play either role depending on context, and it is not yet known how the brain stores and uses information associated with such lexical items in context. We examined these issues by recording event-related potentials (ERPs) in response to unambiguous nouns (e.g. 'beer'), unambiguous verbs (e. g. 'eat'), class-ambiguous words and pseudowords used as nouns or verbs within two types of minimally contrastive sentence contexts: noun-predicting (e.g. 'John wanted THE [target] but.') and verb-predicting ('John wanted TO [target] but.'). Our results indicate that the nature of neural processing for nouns and verbs is a function of both the type of stimulus and the role it is playing. Even when the context completely specifies their role, word class-ambiguous items differ from unambiguous ones over frontal regions by approximately 150 ms. Moreover, whereas pseudowords elicit larger N400s when used as verbs than when used as nouns, unambiguous nouns and ambiguous words used as nouns elicit more frontocentral negativity than unambiguous verbs and ambiguous words used as verbs, respectively. Additionally, unambiguous verbs elicit a left-lateralized, anterior positivity (approximately 200 ms) not observed for any other stimulus type, though only when these items are used appropriately as verbs (i.e. in verb-predicting contexts). In summary, the pattern of neural activity observed in response to lexical items depends on their general

  5. On the pressure response in the brain due to short duration blunt impacts.

    Directory of Open Access Journals (Sweden)

    Christopher W Pearce

    Full Text Available When the head is subject to non-penetrating (blunt impact, contusion-type injuries are commonly identified beneath the impact site (the coup and, in some instances, at the opposite pole (the contre-coup. This pattern of injury has long eluded satisfactory explanation and blunt head injury mechanisms in general remain poorly understood. There are only a small number of studies in the open literature investigating the head's response to short duration impacts, which can occur in collisions with light projectiles. As such, the head impact literature to date has focussed almost exclusively on impact scenarios which lead to a quasi-static pressure response in the brain. In order to investigate the response of the head to a wide range of impact durations, parametric numerical studies were performed on a highly bio-fidelic finite element model of the human head created from in vivo magnetic resonance imaging (MRI scan data with non-linear tissue material properties. We demonstrate that short duration head impacts can lead to potentially deleterious transients of positive and negative intra-cranial pressure over an order of magnitude larger than those observed in the quasi-static regime despite reduced impact force and energy. The onset of this phenomenon is shown to be effectively predicted by the ratio of impact duration to the period of oscillation of the first ovalling mode of the system. These findings point to dramatically different pressure distributions in the brain and hence different patterns of injury depending on projectile mass, and provide a potential explanation for dual coup/contre-coup injuries observed clinically.

  6. Brain stem adenosine receptors modulate centrally mediated hypotensive responses in conscious rats: A review

    Directory of Open Access Journals (Sweden)

    Noha N. Nassar

    2015-05-01

    Full Text Available Adenosine is implicated in the modulation of cardiovascular responses either at the peripheral or at central level in experimental animals. However, there are no dedicated reviews on the involvement of adenosine in mediating the hypotensive response of centrally administered clonidine in general and specifically in aortically barodenervated rats (ABD. The conscious ABD rat model exhibits surgically induced baroreflex dysfunction and exaggerated hypotensive response, compared with conscious sham-operated (SO rats. The current review focuses on, the role of adenosine receptors in blood pressure (BP regulation and their possible crosstalk with other receptors e.g. imidazoline (I1 and alpha (α2A adrenergic receptor (AR. The former receptor is a molecular target for clonidine, whose hypotensive effect is enhanced approx. 3-fold in conscious ABD rats. We also discussed how the balance between the brain stem adenosine A1 and A2A receptors is regulated by baroreceptors and how such balance influences the centrally mediated hypotensive responses. The use of the ABD rat model yielded insight into the downstream signaling cascades following clonidine-evoked hypotension in a surgical model of baroreflex dysfunction.

  7. Unsupervised feature learning improves prediction of human brain activity in response to natural images.

    Directory of Open Access Journals (Sweden)

    Umut Güçlü

    2014-08-01

    Full Text Available Encoding and decoding in functional magnetic resonance imaging has recently emerged as an area of research to noninvasively characterize the relationship between stimulus features and human brain activity. To overcome the challenge of formalizing what stimulus features should modulate single voxel responses, we introduce a general approach for making directly testable predictions of single voxel responses to statistically adapted representations of ecologically valid stimuli. These representations are learned from unlabeled data without supervision. Our approach is validated using a parsimonious computational model of (i how early visual cortical representations are adapted to statistical regularities in natural images and (ii how populations of these representations are pooled by single voxels. This computational model is used to predict single voxel responses to natural images and identify natural images from stimulus-evoked multiple voxel responses. We show that statistically adapted low-level sparse and invariant representations of natural images better span the space of early visual cortical representations and can be more effectively exploited in stimulus identification than hand-designed Gabor wavelets. Our results demonstrate the potential of our approach to better probe unknown cortical representations.

  8. Event-related brain responses while listening to entire pieces of music.

    Science.gov (United States)

    Poikonen, H; Alluri, V; Brattico, E; Lartillot, O; Tervaniemi, M; Huotilainen, M

    2016-01-15

    Brain responses to discrete short sounds have been studied intensively using the event-related potential (ERP) method, in which the electroencephalogram (EEG) signal is divided into epochs time-locked to stimuli of interest. Here we introduce and apply a novel technique which enables one to isolate ERPs in human elicited by continuous music. The ERPs were recorded during listening to a Tango Nuevo piece, a deep techno track and an acoustic lullaby. Acoustic features related to timbre, harmony, and dynamics of the audio signal were computationally extracted from the musical pieces. Negative deflation occurring around 100 milliseconds after the stimulus onset (N100) and positive deflation occurring around 200 milliseconds after the stimulus onset (P200) ERP responses to peak changes in the acoustic features were distinguishable and were often largest for Tango Nuevo. In addition to large changes in these musical features, long phases of low values that precede a rapid increase - and that we will call Preceding Low-Feature Phases - followed by a rapid increase enhanced the amplitudes of N100 and P200 responses. These ERP responses resembled those to simpler sounds, making it possible to utilize the tradition of ERP research with naturalistic paradigms. PMID:26550950

  9. The Impact of Reading Intervention on Brain Responses Underlying Language in Children With Autism.

    Science.gov (United States)

    Murdaugh, Donna L; Deshpande, Hrishikesh D; Kana, Rajesh K

    2016-01-01

    Deficits in language comprehension have been widely reported in children with autism spectrum disorders (ASD), with behavioral and neuroimaging studies finding increased reliance on visuospatial processing to aid in language comprehension. However, no study to date, has taken advantage of this strength in visuospatial processing to improve language comprehension difficulties in ASD. This study used a translational neuroimaging approach to test the role of a visual imagery-based reading intervention in improving the brain circuitry underlying language processing in children with ASD. Functional magnetic resonance imaging (MRI), in a longitudinal study design, was used to investigate intervention-related change in sentence comprehension, brain activation, and functional connectivity in three groups of participants (age 8-13 years): an experimental group of ASD children (ASD-EXP), a wait-list control group of ASD children (ASD-WLC), and a group of typically developing control children. After intervention, the ASD-EXP group showed significant increase in activity in visual and language areas and right-hemisphere language area homologues, putamen, and thalamus, suggestive of compensatory routes to increase proficiency in reading comprehension. Additionally, ASD children who had the most improvement in reading comprehension after intervention showed greater functional connectivity between left-hemisphere language areas, the middle temporal gyrus and inferior frontal gyrus while reading high imagery sentences. Thus, the findings of this study, which support the principles of dual coding theory [Paivio 2007], suggest the potential of a strength-based reading intervention in changing brain responses and facilitating better reading comprehension in ASD children. Autism Res 2015. © 2015 International Society for Autism Research, Wiley Periodicals, Inc. PMID:26016818

  10. Respuesta hemodinámica con el entrenamiento en resistencia y fuerza muscular de miembros superiores en rehabilitación cardiaca Hemodynamic response to training in resistance and muscular strength of upper limbs in cardiac rehabilitation

    Directory of Open Access Journals (Sweden)

    Diana M Camargo

    2007-08-01

    de 1,92 ± 2,49 lb (pAntecedentes: training of muscular strength in patients with cardiovascular events was totally contraindicated because of the risk of incrementing the systolic and diastolic arterial pressure values, as well as the submission to a myocardial overload. Objective: evaluate the hemodynamic response (heart rate, arterial pressure during the resistance to muscular strength training in patients assisting to a heart rehabilitation program. Design: quasi experimental prospective study. Setting: resistance training to muscular strength in upper limbs to patients during stage II of cardiac rehabilitation was realized. Subjects: 175 patients were included. 135 men and 40 women with mean age 58.79 years with coronary disease, with or without revascularization procedures, valvular surgery, syncope and surgical correction of congenital heart disease. Procedure: previous aerobic training (treadmill or static bicycle, muscular strength evaluation was realized through maximal repetition and the strength training was initiated at 30%-50% of this, in a three different exercise circuit in upper limbs, 10 repetitions in three series with a twice a week frequency. Besides, monitoring of heart frequency, electrocardiogram by telemetry (V5, arterial pressure recording before, during and after the session, and subjective perception of the effort by the Borg scale were made, and signs and symptoms of intolerance to the activity or decompensation were observed. For the statistical analysis, measures of central tendency with the cardiovascular changes were used and in order to compare the change in muscular strength, a paired t test with significance level 0.05 was utilized. Results: mean muscular strength with maximal repetition evidenced a significant increase of 1.92 ± 2.49 lb (p<0.001 in the general population, with an increment of 2.03 ± 2.57 lb (p<0.001 in men and of 1.46 ± 2.1 lb (p<0.001 in women. The muscular resistance training was realized with a mean load of

  11. Cellular response of the blood-brain barrier to injury: Potential biomarkers and therapeutic targets for brain regeneration.

    Science.gov (United States)

    Tenreiro, M M; Ferreira, R; Bernardino, L; Brito, M A

    2016-07-01

    Endothelial cells are the main component of the blood-brain barrier (BBB), a vital structure for maintaining brain homeostasis that is seriously disrupted in various neurological pathologies. Therefore, vascular-targeted therapies may bring advantages for the prevention and treatment of brain disorders. In this sense, novel methods to identify and evaluate endothelial damage have been developed and include the detection of circulating endothelial cells, endothelial progenitor cells, endothelial microparticles and exosomes. These cells and cellular structures have been documented in numerous diseases, and increasingly in neurodegenerative disorders, which have led many to assume that they can either be possible biomarkers or tools of repair. Therefore, the purpose of this review is to discuss available data on BBB endothelial damage occurring in two pathologies of the central nervous system, Alzheimer's disease and stroke, which exemplify conditions where chronic and acute vascular damage occur, respectively. The ultimate goal is to identify useful biomarkers and/or therapeutic tools in the healthy and diseased brain that can be used for the treatment of neurodegenerative diseases where BBB permeability and integrity are impaired. PMID:26996728

  12. Post-treatment vascular leakage and inflammatory responses around brain cysts in porcine neurocysticercosis.

    Directory of Open Access Journals (Sweden)

    Siddhartha Mahanty

    2015-03-01

    Full Text Available Cysticidal treatment of neurocysticercosis, an infection of humans and pig brains with Taenia solium, results in an early inflammatory response directed to cysts causing seizures and focal neurological manifestations. Treatment-induced pericystic inflammation and its association with blood brain barrier (BBB dysfunction, as determined by Evans blue (EB extravasation, was studied in infected untreated and anthelmintic-treated pigs. We compared the magnitude and extent of the pericystic inflammation, presence of EB-stained capsules, the level of damage to the parasite, expression of genes for proinflammatory and regulatory cytokines, chemokines, and tissue remodeling by quantitative PCR assays between treated and untreated infected pigs and between EB-stained (blue and non stained (clear cysts. Inflammatory scores were higher in pericystic tissues from EB-stained cysts compared to clear cysts from untreated pigs and also from anthelmintic-treated pigs 48 hr and 120 hr after treatment. The degree of inflammation correlated with the severity of cyst wall damage and both increased significantly at 120 hours. Expression levels of the proinflammatory genes for IL-6, IFN-γ, TNF-α were higher in EB-stained cysts compared to clear cysts and unaffected brain tissues, and were generally highest at 120 hr. Additionally, expression of some markers of immunoregulatory activity (IL-10, IL-2Rα were decreased in EB-stained capsules. An increase in other markers for regulatory T cells (CTLA4, FoxP3 was found, as well as significant increases in expression of two metalloproteases, MMP1 and MMP2 at 48 hr and 120 hr post-treatment. We conclude that the increase in severity of the inflammation caused by treatment is accompanied by both a proinflammatory and a complex regulatory response, largely limited to pericystic tissues with compromised vascular integrity. Because treatment induced inflammation occurs in porcine NCC similar to that in human cases, this model

  13. EGFR mutations are associated with favorable intracranial response and progression-free survival following brain irradiation in non-small cell lung cancer patients with brain metastases

    International Nuclear Information System (INIS)

    The presence of epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancer (NSCLC) is associated with increased radiosensitivity in vitro. However, the results from clinical studies regarding the radiosensitivity in NSCLC with mutant EGFR are inconclusive. We retrospectively analyzed our NSCLC patients who had been regularly followed up by imaging studies after irradiation for brain metastases, and investigated the impact of EGFR mutations on radiotherapy (RT). Forty-three patients with brain metastases treated with RT, together with EGFR mutation status, demographics, smoking history, performance status, recursive partitioning analysis (RPA) class, tumor characteristics, and treatment modalities, were included. Radiological images were taken at 1 to 3 months after RT, and 3 to 6 months thereafter. Radiographic response was evaluated by RECIST criteria version 1.1 according to the intracranial images before and after RT. Log-rank test and Cox regression model were used to correlate EGFR mutation status and other clinical features with intracranial radiological progression-free survival (RPFS) and overall survival (OS). The median follow-up duration was 15 months. Patients with mutant EGFR had higher response rates to brain RT than those with wild-type EGFR (80% vs. 46%; p = 0.037). Logistic regression analysis showed that EGFR mutation status is the only predictor for treatment response (p = 0.032). The median intracranial RPFS was 18 months (95% CI = 8.33-27.68 months). In Cox regression analysis, mutant EGFR (p = 0.025) and lower RPA class (p = 0.026) were associated with longer intracranial RPFS. EGFR mutation status (p = 0.061) and performance status (p = 0.076) had a trend to predict OS. Mutant EGFR in NSCLC patients is an independent prognostic factor for better treatment response and longer intracranial RPFS following RT for brain metastases

  14. Effects of BURP Maneuver on the Hemodynamics and QT and P Dispersions in ECG in Cardiac Surgery Patients

    OpenAIRE

    DEMİRHAN, A.; BİLGİ, M.; TEKELİOĞLU, Ü. Y.; Akkaya, A; ERDEM, K.; Öztürk, S.; KURT, A. D.; Koçoğlu, H.

    2014-01-01

    Effects of BURP Maneuver on the Hemodynamics and QT and P Dispersions in ECG in Cardiac Surgery PatientsObjective: In this study, we aimed to investigate the possible effects of “backward-upward right-sided pressure” (BURP) maneuver applied during tracheal intubation (TI) in patients who will undergo coronary artery baypas surgery on hemodynamic response and QT dispersion (QTd) and P wave dispersion (Pd).Material and Methods: 40 patients undergoing elective coronary artery bypas graft surgery...

  15. Characterization of Selenoprotein M and Its Response to Selenium Deficiency in Chicken Brain.

    Science.gov (United States)

    Huang, Jia-Qiang; Ren, Fa-Zheng; Jiang, Yun-Yun; Lei, XinGen

    2016-04-01

    Selenoprotein M (SelM) may function as thiol disulfide oxidoreductase that participates in the formation of disulfide bonds and can be implicated in calcium responses. SelM may have a functional role in catalyzing free radicals and has been associated with Alzheimer's disease (AD). However, studies of SelM in chicken remain very limited. In this study, two groups of day-old broiler chicks (n = 40/group) were fed a corn-soy basal diet (BD, 13 μg Se/kg) and BD supplemented with Se (as sodium selenite) at 0.3 mg/kg. The brain was collected at 14, 21, 28, and 42 days of age. We performed a sequence analysis and predicted the structure and function of SelM. We also investigated the effects of Se deficiency on the expression of Selt, Selw, and Selm and the Se status in the chicken brain. The results show that Se deficiency induced the lower (P chicken, which might shed light on the role of SelM in human neurodegenerative disease. More studies are needed to confirm our conclusion. PMID:26315306

  16. Brain mechanisms that underlie the effects of motivational audiovisual stimuli on psychophysiological responses during exercise.

    Science.gov (United States)

    Bigliassi, Marcelo; Silva, Vinícius B; Karageorghis, Costas I; Bird, Jonathan M; Santos, Priscila C; Altimari, Leandro R

    2016-05-01

    Motivational audiovisual stimuli such as music and video have been widely used in the realm of exercise and sport as a means by which to increase situational motivation and enhance performance. The present study addressed the mechanisms that underlie the effects of motivational stimuli on psychophysiological responses and exercise performance. Twenty-two participants completed fatiguing isometric handgrip-squeezing tasks under two experimental conditions (motivational audiovisual condition and neutral audiovisual condition) and a control condition. Electrical activity in the brain and working muscles was analyzed by use of electroencephalography and electromyography, respectively. Participants were asked to squeeze the dynamometer maximally for 30s. A single-item motivation scale was administered after each squeeze. Results indicated that task performance and situational motivational were superior under the influence of motivational stimuli when compared to the other two conditions (~20% and ~25%, respectively). The motivational stimulus downregulated the predominance of low-frequency waves (theta) in the right frontal regions of the cortex (F8), and upregulated high-frequency waves (beta) in the central areas (C3 and C4). It is suggested that motivational sensory cues serve to readjust electrical activity in the brain; a mechanism by which the detrimental effects of fatigue on the efferent control of working muscles is ameliorated. PMID:26948160

  17. Predicting the Probability of Abnormal Stimulated Growth Hormone Response in Children After Radiotherapy for Brain Tumors

    International Nuclear Information System (INIS)

    Purpose: To develop a mathematical model utilizing more readily available measures than stimulation tests that identifies brain tumor survivors with high likelihood of abnormal growth hormone secretion after radiotherapy (RT), to avoid late recognition and a consequent delay in growth hormone replacement therapy. Methods and Materials: We analyzed 191 prospectively collected post-RT evaluations of peak growth hormone level (arginine tolerance/levodopa stimulation test), serum insulin-like growth factor 1 (IGF-1), IGF-binding protein 3, height, weight, growth velocity, and body mass index in 106 children and adolescents treated for ependymoma (n = 72), low-grade glioma (n = 28) or craniopharyngioma (n = 6), who had normal growth hormone levels before RT. Normal level in this study was defined as the peak growth hormone response to the stimulation test ≥7 ng/mL. Results: Independent predictor variables identified by multivariate logistic regression with high statistical significance (p < 0.0001) included IGF-1 z score, weight z score, and hypothalamic dose. The developed predictive model demonstrated a strong discriminatory power with an area under the receiver operating characteristic curve of 0.883. At a potential cutoff point of probability of 0.3 the sensitivity was 80% and specificity 78%. Conclusions: Without unpleasant and expensive frequent stimulation tests, our model provides a quantitative approach to closely follow the growth hormone secretory capacity of brain tumor survivors. It allows identification of high-risk children for subsequent confirmatory tests and in-depth workup for diagnosis of growth hormone deficiency.

  18. Predicting the Probability of Abnormal Stimulated Growth Hormone Response in Children After Radiotherapy for Brain Tumors

    Energy Technology Data Exchange (ETDEWEB)

    Hua Chiaho, E-mail: Chia-Ho.Hua@stjude.org [Department of Radiological Sciences, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Wu Shengjie [Department of Biostatistics, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Chemaitilly, Wassim [Division of Endocrinology, Department of Pediatric Medicine, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Lukose, Renin C.; Merchant, Thomas E. [Department of Radiological Sciences, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States)

    2012-11-15

    Purpose: To develop a mathematical model utilizing more readily available measures than stimulation tests that identifies brain tumor survivors with high likelihood of abnormal growth hormone secretion after radiotherapy (RT), to avoid late recognition and a consequent delay in growth hormone replacement therapy. Methods and Materials: We analyzed 191 prospectively collected post-RT evaluations of peak growth hormone level (arginine tolerance/levodopa stimulation test), serum insulin-like growth factor 1 (IGF-1), IGF-binding protein 3, height, weight, growth velocity, and body mass index in 106 children and adolescents treated for ependymoma (n = 72), low-grade glioma (n = 28) or craniopharyngioma (n = 6), who had normal growth hormone levels before RT. Normal level in this study was defined as the peak growth hormone response to the stimulation test {>=}7 ng/mL. Results: Independent predictor variables identified by multivariate logistic regression with high statistical significance (p < 0.0001) included IGF-1 z score, weight z score, and hypothalamic dose. The developed predictive model demonstrated a strong discriminatory power with an area under the receiver operating characteristic curve of 0.883. At a potential cutoff point of probability of 0.3 the sensitivity was 80% and specificity 78%. Conclusions: Without unpleasant and expensive frequent stimulation tests, our model provides a quantitative approach to closely follow the growth hormone secretory capacity of brain tumor survivors. It allows identification of high-risk children for subsequent confirmatory tests and in-depth workup for diagnosis of growth hormone deficiency.

  19. Hemodynamic significance of internal carotid artery disease

    DEFF Research Database (Denmark)

    Schroeder, T

    1988-01-01

    most indirect tests become positive at relatively small pressure gradients. Studies of cerebral blood flow at rest and during cerebral vasodilation makes it possible to identify patients with severe reduction of cerebral perfusion pressure. Such hemodynamic failure of one hemisphere may be identified...... can a significant improvement in baseline flow occur. Flow reserve determined by cerebral vasodilation, however, will improve in most patients with hemodynamic failure. In addition, some patients in the low-pressure group develop marked, but temporary, hyperperfusion after reconstruction of very high...

  20. Effects of L-glutamine supplementation on maternal and fetal hemodynamics in gestating ewes exposed to alcohol

    OpenAIRE

    Sawant, Onkar B.; Ramadoss, Jayanth; Hankins, Gary D.; Wu, Guoyao; Washburn, Shannon E.

    2014-01-01

    Not much is known about effects of gestational alcohol exposure on maternal and fetal cardiovascular adaptations. This study determined whether maternal binge alcohol exposure and L-glutamine supplementation could affect maternal-fetal hemodynamics and fetal regional brain blood flow during the brain growth spurt period. Pregnant sheep were randomly assigned to one of four groups: saline control, alcohol (1.75–2.5 g/kg body weight), glutamine (100 mg/kg body weight) or alcohol + glutamine. A ...

  1. Modeling learning in brain stem and cerebellar sites responsible for VOR plasticity

    Science.gov (United States)

    Quinn, K. J.; Didier, A. J.; Baker, J. F.; Peterson, B. W.

    1998-01-01

    A simple model of vestibuloocular reflex (VOR) function was used to analyze several hypotheses currently held concerning the characteristics of VOR plasticity. The network included a direct vestibular pathway and an indirect path via the cerebellum. An optimization analysis of this model suggests that regulation of brain stem sites is critical for the proper modification of VOR gain. A more physiologically plausible learning rule was also applied to this network. Analysis of these simulation results suggests that the preferred error correction signal controlling gain modification of the VOR is the direct output of the accessory optic system (AOS) to the vestibular nuclei vs. a signal relayed through the cerebellum via floccular Purkinje cells. The potential anatomical and physiological basis for this conclusion is discussed, in relation to our current understanding of the latency of the adapted VOR response.

  2. Common biology of craving across legal and illegal drugs - a quantitative meta-analysis of cue-reactivity brain response.

    Science.gov (United States)

    Kühn, Simone; Gallinat, Jürgen

    2011-04-01

    The present quantitative meta-analysis set out to test whether cue-reactivity responses in humans differ across drugs of abuse and whether these responses constitute the biological basis of drug craving as a core psychopathology of addiction. By means of activation likelihood estimation, we investigated the concurrence of brain regions activated by cue-induced craving paradigms across studies on nicotine, alcohol and cocaine addicts. Furthermore, we analysed the concurrence of brain regions positively correlated with self-reported craving in nicotine and alcohol studies. We found direct overlap between nicotine, alcohol and cocaine cue reactivity in the ventral striatum. In addition, regions of close proximity were observed in the anterior cingulate cortex (ACC; nicotine and cocaine) and amygdala (alcohol, nicotine and cocaine). Brain regions of concurrence in drug cue-reactivity paradigms that overlapped with brain regions of concurrence in self-reported craving correlations were found in the ACC, ventral striatum and right pallidum (for alcohol). This first quantitative meta-analysis on drug cue reactivity identifies brain regions underlying nicotine, alcohol and cocaine dependency, i.e. the ventral striatum. The ACC, right pallidum and ventral striatum were related to drug cue reactivity as well as self-reported craving, suggesting that this set of brain regions constitutes the core circuit of drug craving in nicotine and alcohol addiction. PMID:21261758

  3. Human brain EEG indices of emotions: delineating responses to affective vocalizations by measuring frontal theta event-related synchronization.

    Science.gov (United States)

    Bekkedal, Marni Y V; Rossi, John; Panksepp, Jaak

    2011-10-01

    At present there is no direct brain measure of basic emotional dynamics from the human brain. EEG provides non-invasive approaches for monitoring brain electrical activity to emotional stimuli. Event-related desynchronization/synchronization (ERD/ERS) analysis, based on power shifts in specific frequency bands, has some potential as a method for differentiating responses to basic emotions as measured during brief presentations of affective stimuli. Although there appears to be fairly consistent theta ERS in frontal regions of the brain during the earliest phases of processing affective auditory stimuli, the patterns do not readily distinguish between specific emotions. To date it has not been possible to consistently differentiate brain responses to emotion-specific affective states or stimuli, and some evidence to suggests the theta ERS more likely measures general arousal processes rather than yielding veridical indices of specific emotional states. Perhaps cortical EEG patterns will never be able to be used to distinguish discrete emotional states from the surface of the brain. The implications and limitations of such approaches for understanding human emotions are discussed. PMID:21596060

  4. Cannabis Abusers Show Hypofrontality and Blunted Brain Responses to a Stimulant Challenge in Females but not in Males.

    Science.gov (United States)

    Wiers, Corinde E; Shokri-Kojori, Ehsan; Wong, Christopher T; Abi-Dargham, Anissa; Demiral, Şükrü B; Tomasi, Dardo; Wang, Gene-Jack; Volkow, Nora D

    2016-09-01

    The extent to which cannabis is deleterious to the human brain is not well understood. Here, we test whether cannabis abusers (CA) have impaired frontal function and reactivity to dopaminergic signaling, which are fundamental to relapse in addiction. We measured brain glucose metabolism using PET and [(18)F]FDG both at baseline (placebo) and after challenge with methylphenidate (MP), a dopamine-enhancing drug, in 24 active CA (50% female) and 24 controls (HC; 50% female). Results show that (i) CA had lower baseline glucose metabolism than HC in frontal cortex including anterior cingulate, which was associated with negative emotionality. (ii) MP increased whole-brain glucose metabolism in HC but not in CA; and group by challenge effects were most profound in putamen, caudate, midbrain, thalamus, and cerebellum. In CA, MP-induced metabolic increases in putamen correlated negatively with addiction severity. (iii) There were significant gender effects, such that both the group differences at baseline in frontal metabolism and the attenuated regional brain metabolic responses to MP were observed in female CA but not in male CA. As for other drug addictions, reduced baseline frontal metabolism is likely to contribute to relapse in CA. The attenuated responses to MP in midbrain and striatum are consistent with decreased brain reactivity to dopamine stimulation and might contribute to addictive behaviors in CA. The gender differences suggest that females are more sensitive than males to the adverse effects of cannabis in brain. PMID:27156854

  5. Behavioral responses to and brain distribution of morphine in mature adult and aged mice

    International Nuclear Information System (INIS)

    Mature adult (3-6 mo old) and aged (2 yr old) male ICR mice were injected with 10 to 100 mg/kg morphine, s.c. The ED50 values for running behavior (as measured using Stoelting activity monitors and having each mouse serve as its own control) representing 5 times control activity was approximately 7.5 mg/kg for aged mice and approximately 17.5 mg/kg for the mature adults. The ED50 values for analgesia 1 hr after morphine administration using the tail-flick method (max. response time = 8 sec) were approx. 70 mg/kg for the aged mice and 15 mg/kg for the mature adults. One hour after injecting 3H-morphine at doses of 30 and 100 mg/kg, 0.13 and 0.14% of the doses appeared in brains of aged and mature adult mice, respectively. Regional distribution of the morphine was the same for both age groups. Expressed as percent of total brain morphine, it was as follows: cortex, 30%; midbrain, 18%; cerebellum, 17%; medulla, 12%; pons, 9%; striatum, 8% and periaqueductal gray, 6%. Expressed as g morphine/g tissue for the 2 doses, the distribution was; periaqueductal gray, 30 and 80; striatum, 9 and 34; medulla, 6 and 20 pons; 5 and 19; cerebellum, 4 and 13; midbrain 2.5 and 8.5 and cortex, 2 and 8. These results suggest that the differences in response to morphine by the two age groups were due to age-related differences in opioid receptor populations and/or affinities

  6. Behavioral responses to and brain distribution of morphine in mature adult and aged mice

    Energy Technology Data Exchange (ETDEWEB)

    Burton, C.K.; Ho, I.K.; Hoskins, B.

    1986-03-01

    Mature adult (3-6 mo old) and aged (2 yr old) male ICR mice were injected with 10 to 100 mg/kg morphine, s.c. The ED50 values for running behavior (as measured using Stoelting activity monitors and having each mouse serve as its own control) representing 5 times control activity was approximately 7.5 mg/kg for aged mice and approximately 17.5 mg/kg for the mature adults. The ED50 values for analgesia 1 hr after morphine administration using the tail-flick method (max. response time = 8 sec) were approx. 70 mg/kg for the aged mice and 15 mg/kg for the mature adults. One hour after injecting /sup 3/H-morphine at doses of 30 and 100 mg/kg, 0.13 and 0.14% of the doses appeared in brains of aged and mature adult mice, respectively. Regional distribution of the morphine was the same for both age groups. Expressed as percent of total brain morphine, it was as follows: cortex, 30%; midbrain, 18%; cerebellum, 17%; medulla, 12%; pons, 9%; striatum, 8% and periaqueductal gray, 6%. Expressed as g morphine/g tissue for the 2 doses, the distribution was; periaqueductal gray, 30 and 80; striatum, 9 and 34; medulla, 6 and 20 pons; 5 and 19; cerebellum, 4 and 13; midbrain 2.5 and 8.5 and cortex, 2 and 8. These results suggest that the differences in response to morphine by the two age groups were due to age-related differences in opioid receptor populations and/or affinities.

  7. Hemodynamic aspects of biventricular pacing in heart failure

    OpenAIRE

    Ståhlberg, Marcus

    2010-01-01

    Background and aims Biventricular pacing or cardiac resynchronization therapy (CRT) is an established treatment option for selected heart failure (HF) patients. We aimed at evaluating acute and longer-term hemodynamic effects of different pacemaker programmings in CRT patients. For the latter purpose, 10 CRT patients also received an implantable hemodynamic monitor (IHM), allowing for long-term hemodynamic monitoring during ambulatory periods. Study I The hemodynamic ...

  8. Verbal labels selectively bias brain responses to high-energy foods.

    Science.gov (United States)

    Toepel, Ulrike; Ohla, Kathrin; Hudry, Julie; le Coutre, Johannes; Murray, Micah M

    2014-02-15

    The influence of external factors on food preferences and choices is poorly understood. Knowing which and how food-external cues impact the sensory processing and cognitive valuation of food would provide a strong benefit toward a more integrative understanding of food intake behavior and potential means of interfering with deviant eating patterns to avoid detrimental health consequences for individuals in the long run. We investigated whether written labels with positive and negative (as opposed to 'neutral') valence differentially modulate the spatio-temporal brain dynamics in response to the subsequent viewing of high- and low-energetic food images. Electrical neuroimaging analyses were applied to visual evoked potentials (VEPs) from 20 normal-weight participants. VEPs and source estimations in response to high- and low- energy foods were differentially affected by the valence of preceding word labels over the ~260-300 ms post-stimulus period. These effects were only observed when high-energy foods were preceded by labels with positive valence. Neural sources in occipital as well as posterior, frontal, insular and cingulate regions were down-regulated. These findings favor cognitive-affective influences especially on the visual responses to high-energetic food cues, potentially indicating decreases in cognitive control and goal-adaptive behavior. Inverse correlations between insular activity and effectiveness in food classification further indicate that this down-regulation directly impacts food-related behavior. PMID:24185017

  9. The Acute Inflammatory Response in Trauma / Hemorrhage and Traumatic Brain Injury: Current State and Emerging Prospects

    Directory of Open Access Journals (Sweden)

    Y Vodovotz

    2009-01-01

    Full Text Available Traumatic injury/hemorrhagic shock (T/HS elicits an acute inflammatory response that may result in death. Inflammation describes a coordinated series of molecular, cellular, tissue, organ, and systemic responses that drive the pathology of various diseases including T/HS and traumatic brain injury (TBI. Inflammation is a finely tuned, dynamic, highly-regulated process that is not inherentlydetrimental, but rather required for immune surveillance, optimal post-injury tissue repair, and regeneration. The inflammatory response is driven by cytokines and chemokines and is partiallypropagated by damaged tissue-derived products (Damage-associated Molecular Patterns; DAMP’s.DAMPs perpetuate inflammation through the release of pro-inflammatory cytokines, but may also inhibit anti-inflammatory cytokines. Various animal models of T/HS in mice, rats, pigs, dogs, and nonhumanprimates have been utilized in an attempt to move from bench to bedside. Novel approaches, including those from the field of systems biology, may yield therapeutic breakthroughs in T/HS andTBI in the near future.

  10. Outlier responses reflect sensitivity to statistical structure in the human brain.

    Directory of Open Access Journals (Sweden)

    Marta I Garrido

    Full Text Available We constantly look for patterns in the environment that allow us to learn its key regularities. These regularities are fundamental in enabling us to make predictions about what is likely to happen next. The physiological study of regularity extraction has focused primarily on repetitive sequence-based rules within the sensory environment, or on stimulus-outcome associations in the context of reward-based decision-making. Here we ask whether we implicitly encode non-sequential stochastic regularities, and detect violations therein. We addressed this question using a novel experimental design and both behavioural and magnetoencephalographic (MEG metrics associated with responses to pure-tone sounds with frequencies sampled from a Gaussian distribution. We observed that sounds in the tail of the distribution evoked a larger response than those that fell at the centre. This response resembled the mismatch negativity (MMN evoked by surprising or unlikely events in traditional oddball paradigms. Crucially, responses to physically identical outliers were greater when the distribution was narrower. These results show that humans implicitly keep track of the uncertainty induced by apparently random distributions of sensory events. Source reconstruction suggested that the statistical-context-sensitive responses arose in a temporo-parietal network, areas that have been associated with attention orientation to unexpected events. Our results demonstrate a very early neurophysiological marker of the brain's ability to implicitly encode complex statistical structure in the environment. We suggest that this sensitivity provides a computational basis for our ability to make perceptual inferences in noisy environments and to make decisions in an uncertain world.

  11. Exploring the motivational brain: effects of implicit power motivation on brain activation in response to facial expressions of emotion

    OpenAIRE

    Schultheiss, Oliver C.; Wirth, Michelle M.; WAUGH, CHRISTIAN E.; Stanton, Steven J.; Meier, Elizabeth A.; Reuter-Lorenz, Patricia

    2008-01-01

    This study tested the hypothesis that implicit power motivation (nPower), in interaction with power incentives, influences activation of brain systems mediating motivation. Twelve individuals low (lowest quartile) and 12 individuals high (highest quartile) in nPower, as assessed per content coding of picture stories, were selected from a larger initial participant pool and participated in a functional magnetic resonance imaging study during which they viewed high-dominance (angry faces), low-...

  12. Autoantibodies and immunoglobulins in patients with alcoholic cirrhosis. Relation to measurements of hepatic function and hemodynamics

    DEFF Research Database (Denmark)

    Gluud, C; Tage-Jensen, U; Rubinstein, E; Henriksen, Jens Henrik Sahl

    1984-01-01

    In order to evaluate the possible relation between hepatic function and hemodynamics and the increased humoral immune response of cirrhotic patients, titres of antinuclear antibodies (ANA) and smooth muscle antibodies (SMA) and concentrations of immunoglobulin (Ig) G, A and M were determined in 7...

  13. Bioimpedance Measurement of Segmental Fluid Volumes and Hemodynamics

    Science.gov (United States)

    Montgomery, Leslie D.; Wu, Yi-Chang; Ku, Yu-Tsuan E.; Gerth, Wayne A.; DeVincenzi, D. (Technical Monitor)

    2000-01-01

    Bioimpedance has become a useful tool to measure changes in body fluid compartment volumes. An Electrical Impedance Spectroscopic (EIS) system is described that extends the capabilities of conventional fixed frequency impedance plethysmographic (IPG) methods to allow examination of the redistribution of fluids between the intracellular and extracellular compartments of body segments. The combination of EIS and IPG techniques was evaluated in the human calf, thigh, and torso segments of eight healthy men during 90 minutes of six degree head-down tilt (HDT). After 90 minutes HDT the calf and thigh segments significantly (P < 0.05) lost conductive volume (eight and four percent, respectively) while the torso significantly (P < 0.05) gained volume (approximately three percent). Hemodynamic responses calculated from pulsatile IPG data also showed a segmental pattern consistent with vascular fluid loss from the lower extremities and vascular engorgement in the torso. Lumped-parameter equivalent circuit analyses of EIS data for the calf and thigh indicated that the overall volume decreases in these segments arose from reduced extracellular volume that was not completely balanced by increased intracellular volume. The combined use of IPG and EIS techniques enables noninvasive tracking of multi-segment volumetric and hemodynamic responses to environmental and physiological stresses.

  14. Basic Perforator Flap Hemodynamic Mathematical Model

    Science.gov (United States)

    Tao, Youlun; Ding, Maochao; Wang, Aiguo; Zhuang, Yuehong; Chang, Shi-Min; Mei, Jin; Hallock, Geoffrey G.

    2016-01-01

    Background: A mathematical model to help explain the hemodynamic characteristics of perforator flaps based on blood flow resistance systems within the flap will serve as a theoretical guide for the future study and clinical applications of these flaps. Methods: There are 3 major blood flow resistance network systems of a perforator flap. These were defined as the blood flow resistance of an anastomosis between artery and artery of adjacent perforasomes, between artery and vein within a perforasome, and then between vein and vein corresponding to the outflow of that perforasome. From this, a calculation could be made of the number of such blood flow resistance network systems that must be crossed for all perforasomes within a perforator flap to predict whether that arrangement would be viable. Results: The summation of blood flow resistance networks from each perforasome in a given perforator flap could predict which portions would likely survive. This mathematical model shows how this is directly dependent on the location of the vascular pedicle to the flap and whether supercharging or superdrainage maneuvers have been added. These configurations will give an estimate of the hemodynamic characteristics for the given flap design. Conclusions: This basic mathematical model can (1) conveniently determine the degree of difficulty for each perforasome within a perforator flap to survive; (2) semiquantitatively allow the calculation of basic hemodynamic parameters; and (3) allow the assessment of the pros and cons expected for each pattern of perforasomes encountered clinically based on predictable hemodynamic observations.

  15. Force plate monitoring of human hemodynamics

    Czech Academy of Sciences Publication Activity Database

    Kříž, J.; Šeba, Petr

    2008-01-01

    Roč. 2, č. 1 (2008), s. 1-9. ISSN 1753-4631 Grant ostatní: GA ČR(CZ) GP202/06/P130; GA MŠk(CZ) LC06002 Institutional research plan: CEZ:AV0Z10100521 Keywords : hemodynamics * balistocardiography * pulse wave velocity Subject RIV: BO - Biophysics www.nonlinearbiomedphys.com

  16. Glomerular hemodynamic changes associated with arteriolar lesions and tubulointerstitial inflammation.

    Science.gov (United States)

    Sánchez-Lozada, Laura G; Tapia, Edilia; Johnson, Richard J; Rodríguez-Iturbe, Bernardo; Herrera-Acosta, Jaime

    2003-10-01

    Glomerular hemodynamic adaptations to loss of renal mass are thought to be the initiating factor of progression to renal failure; however, tubulointerstitial (TI) injury correlates better with progression than with glomerular damage. Thus, it is conceivable that tubulointerstitial alterations participate in the pathophysiology of renal disease progression by modifying the adaptive responses of glomerular hemodynamics. In experimental models of progressive renal disease, suppressing tubulointerstitial inflammatory cell infiltration with anti-inflammatory drugs reduces renal damage despite persistence of systemic hypertension. In recent studies in rats with subtotal renal ablation, we found that treatment with polysulphate pentosan (PPS) and with mycophenolate mofetil (MMF) prevented proteinuria, glomerular hypertension, and hyperfiltration, despite persisting arterial hypertension due to higher afferent resistance. In addition, arteriolopathy was significantly attenuated by MMF, suggesting preservation of vascular structure and function. Association of vascular injury of afferent arterioles, glomerular hemodynamic changes, and renal lesions has been described in other conditions such as hyperuricemia, protein overload, fawn-hooded rats, and aging spontaneously hypertensive rats (SHR). Arteriolopathy results in a maladaptive function that permits the transmission of systemic hypertension to glomerular capillaries. Glomerular hypertension results in mechanical damage to the capillary wall and increased filtration of proteins to tubular lumen. Enhanced tubular reabsorption induces synthesis of proinflammatory and profibrotic factors, resulting in tubulointerstitial inflammation and fibrosis. In conditions in which there is overactivity of the renin-angiotensin system (RAS), such as mild hyperuricemia and protein overload, arteriolopathy is associated with increased glomerular pressure and reduced glomerular plasma flow that results in post-glomerular ischemia and

  17. Resting lateralized activity predicts the cortical response and appraisal of emotions: an fNIRS study.

    Science.gov (United States)

    Balconi, Michela; Grippa, Elisabetta; Vanutelli, Maria Elide

    2015-12-01

    This study explored the effect of lateralized left-right resting brain activity on prefrontal cortical responsiveness to emotional cues and on the explicit appraisal (stimulus evaluation) of emotions based on their valence. Indeed subjective responses to different emotional stimuli should be predicted by brain resting activity and should be lateralized and valence-related (positive vs negative valence). A hemodynamic measure was considered (functional near-infrared spectroscopy). Indeed hemodynamic resting activity and brain response to emotional cues were registered when subjects (N = 19) viewed emotional positive vs negative stimuli (IAPS). Lateralized index response during resting state, LI (lateralized index) during emotional processing and self-assessment manikin rating were considered. Regression analysis showed the significant predictive effect of resting activity (more left or right lateralized) on both brain response and appraisal of emotional cues based on stimuli valence. Moreover, significant effects were found as a function of valence (more right response to negative stimuli; more left response to positive stimuli) during emotion processing. Therefore, resting state may be considered a predictive marker of the successive cortical responsiveness to emotions. The significance of resting condition for emotional behavior was discussed. PMID:25862673

  18. Permeability and contractile responses of collecting lymphatic vessels elicited by atrial and brain natriuretic peptides.

    Science.gov (United States)

    Scallan, Joshua P; Davis, Michael J; Huxley, Virginia H

    2013-10-15

    Atrial and brain natriuretic peptides (ANP and BNP, respectively) are cardiac hormones released into the bloodstream in response to hypervolaemia or fluid shifts to the central circulation. The actions of both peptides include natriuresis and diuresis, a decrease in systemic blood pressure, and inhibition of the renin-angiotensin-aldosterone system. Further, ANP and BNP elicit increases in blood microvessel permeability sufficient to cause protein and fluid extravasation into the interstitium to reduce the vascular volume. Given the importance of the lymphatic vasculature in maintaining fluid balance, we tested the hypothesis that ANP or BNP (100 nM) would likewise elevate lymphatic permeability (Ps) to serum albumin. Using a microfluorometric technique adapted to in vivo lymphatic vessels, we determined that rat mesenteric collecting lymphatic Ps to rat serum albumin increased by 2.0 ± 0.4-fold (P = 0.01, n = 7) and 2.7 ± 0.8-fold (P = 0.07, n = 7) with ANP and BNP, respectively. In addition to measuring Ps responses, we observed changes in spontaneous contraction amplitude and frequency from the albumin flux tracings in vivo. Notably, ANP abolished spontaneous contraction amplitude (P = 0.005) and frequency (P = 0.006), while BNP augmented both parameters by ∼2-fold (P lymphatic permeability opposes the absorptive function of the lymphatic capillaries, and aids in the retention of protein and fluid in the interstitial space to counteract volume expansion. PMID:23897233

  19. Association between brain natriuretic peptide, markers of inflammation and the objective and subjective response to cardiac resynchronization therapy

    DEFF Research Database (Denmark)

    Brouwers, Corline; Versteeg, Henneke; Meine, Mathias;

    2014-01-01

    Introduction: Studies suggest that cardiac resynchronization therapy (CRT) can induce a decrease in brain natriuretic peptide (BNP) and systemic inflammation, which may be associated with CRT-response. However, the evidence is inconclusive. We examined levels of BNP and inflammatory markers from ...

  20. Face the hierarchy: ERP and oscillatory brain responses in social rank processing.

    Directory of Open Access Journals (Sweden)

    Audrey Breton

    Full Text Available Recognition of social hierarchy is a key feature that helps us navigate through our complex social environment. Neuroimaging studies have identified brain structures involved in the processing of hierarchical stimuli but the precise temporal dynamics of brain activity associated with such processing remains largely unknown. Here, we used electroencephalography to examine the effect of social hierarchy on neural responses elicited by faces. In contrast to previous studies, the key manipulation was that a hierarchical context was constructed, not by varying facial expressions, but by presenting neutral-expression faces in a game setting. Once the performance-based hierarchy was established, participants were presented with high-rank, middle-rank and low-rank player faces and had to evaluate the rank of each face with respect to their own position. Both event-related potentials and task-related oscillatory activity were investigated. Three main findings emerge from the study. First, the experimental manipulation had no effect on the early N170 component, which may suggest that hierarchy did not modulate the structural encoding of neutral-expression faces. Second, hierarchy significantly modulated the amplitude of the late positive potential (LPP within a 400-700 ms time-window, with more a prominent LPP occurring when the participants processed the face of the highest-rank player. Third, high-rank faces were associated with the highest reduction of alpha power. Taken together these findings provide novel electrophysiological evidence for enhanced allocation of attentional resource in the presence of high-rank faces. At a broader level, this study brings new insights into the neural processing underlying social categorization.