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Sample records for brain potentials indications

  1. Event-related brain potentials as indices of mental workload and attentional allocation

    Science.gov (United States)

    Kramer, Arthur F.; Donchin, Emanuel; Wickens, Christopher D.

    1988-01-01

    Over the past decade considerable strides were made in explicating the antecedant conditions necessary for the elicitation, and the modulation of the amplitude and latency, of a number of components of the event-related brain potential (ERP). The focus of this report is on P300. The degree to which the psychophysiological measures contribute to issues in two real-world domains (communication devices for the motor impaired and the assessment of mental workload of aircraft pilots) are examined.

  2. Science Letters: Brain natriuretic peptide: A potential indicator of cardiomyogenesis after autologous mesenchymal stem cell transplantation?

    Institute of Scientific and Technical Information of China (English)

    LI Nan; WANG Jian-an

    2006-01-01

    We observed in a pilot study that there was a transient elevation of brain natriuretic peptide (BNP) level shortly after the transplantation in the patient with ischemic heart failure, which is unexplainable by the simultaneous increase of the cardiac output and six-minute walk distance. Similar findings were observed in the phase I trial. We postulated on the basis of the finding of Fukuda in vitro that this transient elevation of BNP level against the improvement of cardiac function and exercise capacity might indicate cardiomyogenesis in patients after mesenchymal stem cell transplantation. Further study is warranted to verify the hypothesis.

  3. Acoustic Noise Alters Selective Attention Processes as Indicated by Direct Current (DC Brain Potential Changes

    Directory of Open Access Journals (Sweden)

    Karin Trimmel

    2014-09-01

    Full Text Available Acoustic environmental noise, even of low to moderate intensity, is known to adversely affect information processing in animals and humans via attention mechanisms. In particular, facilitation and inhibition of information processing are basic functions of selective attention. Such mechanisms can be investigated by analyzing brain potentials under conditions of externally directed attention (intake of environmental information versus internally directed attention (rejection of environmental stimuli and focusing on memory/planning processes. This study investigated brain direct current (DC potential shifts—which are discussed to represent different states of cortical activation—of tasks that require intake and rejection of environmental information under noise. It was hypothesized that without background noise rejection tasks would show more positive DC potential changes compared to intake tasks and that under noise both kinds of tasks would show positive DC shifts as an expression of cortical inhibition caused by noise. DC potential shifts during intake and rejection tasks were analyzed at 16 standard locations in 45 persons during irrelevant speech or white noise vs. control condition. Without noise, rejection tasks were associated with more positive DC potential changes compared to intake tasks. During background noise, however, this difference disappeared and both kinds of tasks led to positive DC shifts. Results suggest—besides some limitations—that noise modulates selective attention mechanisms by switching to an environmental information processing and noise rejection mode, which could represent a suggested “attention shift”. Implications for fMRI studies as well as for public health in learning and performance environments including susceptible persons are discussed.

  4. Brain potentials indicate the effect of other observers' emotions on perceptions of facial attractiveness.

    Science.gov (United States)

    Huang, Yujing; Pan, Xuwei; Mo, Yan; Ma, Qingguo

    2016-03-23

    Perceptions of facial attractiveness are sensitive to emotional expression of the perceived face. However, little is known about whether the emotional expression on the face of another observer of the perceived face may have an effect on perceptions of facial attractiveness. The present study used event-related potential technique to examine social influence of the emotional expression on the face of another observer of the perceived face on perceptions of facial attractiveness. The experiment consisted of two phases. In the first phase, a neutral target face was paired with two images of individuals gazing at the target face with smiling, fearful or neutral expressions. In the second phase, participants were asked to judge the attractiveness of the target face. We found that a target face was more attractive when other observers positively gazing at the target face in contrast to the condition when other observers were negative. Additionally, the results of brain potentials showed that the visual positive component P3 with peak latency from 270 to 330 ms was larger after participants observed the target face paired with smiling individuals than the target face paired with neutral individuals. These findings suggested that facial attractiveness of an individual may be influenced by the emotional expression on the face of another observer of the perceived face. PMID:26601630

  5. Brain potentials indicate the effect of other observers' emotions on perceptions of facial attractiveness.

    Science.gov (United States)

    Huang, Yujing; Pan, Xuwei; Mo, Yan; Ma, Qingguo

    2016-03-23

    Perceptions of facial attractiveness are sensitive to emotional expression of the perceived face. However, little is known about whether the emotional expression on the face of another observer of the perceived face may have an effect on perceptions of facial attractiveness. The present study used event-related potential technique to examine social influence of the emotional expression on the face of another observer of the perceived face on perceptions of facial attractiveness. The experiment consisted of two phases. In the first phase, a neutral target face was paired with two images of individuals gazing at the target face with smiling, fearful or neutral expressions. In the second phase, participants were asked to judge the attractiveness of the target face. We found that a target face was more attractive when other observers positively gazing at the target face in contrast to the condition when other observers were negative. Additionally, the results of brain potentials showed that the visual positive component P3 with peak latency from 270 to 330 ms was larger after participants observed the target face paired with smiling individuals than the target face paired with neutral individuals. These findings suggested that facial attractiveness of an individual may be influenced by the emotional expression on the face of another observer of the perceived face.

  6. Processing of visual semantic information to concrete words : temporal dynamics and neural mechanisms indicated by event-related brain potentials

    NARCIS (Netherlands)

    van Schie, HT; Wijers, AA; Mars, RB; Benjamins, JS; Stowe, LA; Mars, Ruben

    2005-01-01

    Event-related brain potentials were used to study the retrieval of visual semantic information to concrete words, and to investigate possible structural overlap between visual object working memory and concreteness effects in word processing. Subjects performed an object working memory task that inv

  7. Processing of visual semantic information to concrete words: temporal dynamics and neural mechanisms indicated by event-related brain potentials

    NARCIS (Netherlands)

    Schie, H.T. van; Wijers, A.A.; Mars, R.B.; Benjamins, J.S.; Stowe, L.A.

    2005-01-01

    Event-related brain potentials were used to study the retrieval of visual semantic information to concrete words, and to investigate possible structural overlap between visual object working memory and concreteness effects in word processing. Subjects performed an object working memory task that inv

  8. Aerobic Fitness and Cognitive Development: Event-Related Brain Potential and Task Performance Indices of Executive Control in Preadolescent Children

    Science.gov (United States)

    Hillman, Charles H.; Buck, Sarah M.; Themanson, Jason R.; Pontifex, Matthew B.; Castelli, Darla M.

    2009-01-01

    The relationship between aerobic fitness and executive control was assessed in 38 higher- and lower-fit children (M[subscript age] = 9.4 years), grouped according to their performance on a field test of aerobic capacity. Participants performed a flanker task requiring variable amounts of executive control while event-related brain potential…

  9. The present indication and future of deep brain stimulation.

    Science.gov (United States)

    Sugiyama, Kenji; Nozaki, Takao; Asakawa, Tetsuya; Koizumi, Shinichiro; Saitoh, Osamu; Namba, Hiroki

    2015-01-01

    The use of electrical stimulation to treat pain in human disease dates back to ancient Rome or Greece. Modern deep brain stimulation (DBS) was initially applied for pain treatment in the 1960s, and was later used to treat movement disorders in the 1990s. After recognition of DBS as a therapy for central nervous system (CNS) circuit disorders, DBS use showed drastic increase in terms of adaptability to disease and the patient's population. More than 100,000 patients have received DBS therapy worldwide. The established indications for DBS are Parkinson's disease, tremor, and dystonia, whereas global indications of DBS expanded to other neuronal diseases or disorders such as neuropathic pain, epilepsy, and tinnitus. DBS is also experimentally used to manage cognitive disorders and psychiatric diseases such as major depression, obsessive-compulsive disorder (OCD), Tourette's syndrome, and eating disorders. The importance of ethics and conflicts surrounding the regulation and freedom of choice associated with the application of DBS therapy for new diseases or disorders is increasing. These debates are centered on the use of DBS to treat new diseases and disorders as well as its potential to enhance ability in normal healthy individuals. Here we present three issues that need to be addressed in the future: (1) elucidation of the mechanisms of DBS, (2) development of new DBS methods, and (3) miniaturization of the DBS system. With the use of DBS, functional neurosurgery entered into the new era that man can manage and control the brain circuit to treat intractable neuronal diseases and disorders. PMID:25925757

  10. Brain-Based Indices for User System Symbiosis

    NARCIS (Netherlands)

    Erp, J.B.F. van; Veltman, J.A.; Grootjen, M.

    2010-01-01

    The future generation user system interfaces need to be user-centric which goes beyond user-friendly and includes understanding and anticipating user intentions. We introduce the concept of operator models, their role in implementing user-system symbiosis, and the usefulness of brain-based indices o

  11. Potential Moderators of Physical Activity on Brain Health

    Directory of Open Access Journals (Sweden)

    Regina L. Leckie

    2012-01-01

    Full Text Available Age-related cognitive decline is linked to numerous molecular, structural, and functional changes in the brain. However, physical activity is a promising method of reducing unfavorable age-related changes. Physical activity exerts its effects on the brain through many molecular pathways, some of which are regulated by genetic variants in humans. In this paper, we highlight genes including apolipoprotein E (APOE, brain derived neurotrophic factor (BDNF, and catechol-O-methyltransferase (COMT along with dietary omega-3 fatty acid, docosahexaenoic acid (DHA, as potential moderators of the effect of physical activity on brain health. There are a growing number of studies indicating that physical activity might mitigate the genetic risks for disease and brain dysfunction and that the combination of greater amounts of DHA intake with physical activity might promote better brain function than either treatment alone. Understanding whether genes or other lifestyles moderate the effects of physical activity on neurocognitive health is necessary for delineating the pathways by which brain health can be enhanced and for grasping the individual variation in the effectiveness of physical activity interventions on the brain and cognition. There is a need for future research to continue to assess the factors that moderate the effects of physical activity on neurocognitive function.

  12. Life Potential as a Basic Demographic Indicator

    Science.gov (United States)

    Goerlich, Francisco J.; Soler, Angel

    2013-01-01

    This paper proposes an indicator that integrates life expectancy with the demographic structure of the population for a given society. By doing this, we have a simple indicator of mortality and aging combined, which could be very useful for developed societies. As is widely known, life expectancy at birth is independent of the demographic…

  13. Future of brain stimulation: new targets, new indications, new technology.

    Science.gov (United States)

    Hariz, Marwan; Blomstedt, Patric; Zrinzo, Ludvic

    2013-11-01

    In the last quarter of a century, DBS has become an established neurosurgical treatment for Parkinson's disease (PD), dystonia, and tremors. Improved understanding of brain circuitries and their involvement in various neurological and psychiatric illnesses, coupled with the safety of DBS and its exquisite role as a tool for ethical study of the human brain, have unlocked new opportunities for this technology, both for future therapies and in research. Serendipitous discoveries and advances in structural and functional imaging are providing abundant "new" brain targets for an ever-increasing number of pathologies, leading to investigations of DBS in diverse neurological, psychiatric, behavioral, and cognitive conditions. Trials and "proof of concept" studies of DBS are underway in pain, epilepsy, tinnitus, OCD, depression, and Gilles de la Tourette syndrome, as well as in eating disorders, addiction, cognitive decline, consciousness, and autonomic states. In parallel, ongoing technological development will provide pulse generators with longer battery longevity, segmental electrode designs allowing a current steering, and the possibility to deliver "on-demand" stimulation based on closed-loop concepts. The future of brain stimulation is certainly promising, especially for movement disorders-that will remain the main indication for DBS for the foreseeable future-and probably for some psychiatric disorders. However, brain stimulation as a technique may be at risk of gliding down a slippery slope: Some reports indicate a disturbing trend with suggestions that future DBS may be proposed for enhancement of memory in healthy people, or as a tool for "treatment" of "antisocial behavior" and for improving "morality." PMID:24123327

  14. [123I] HIPDM as a brain perfusion indicator for SPECT

    International Nuclear Information System (INIS)

    The metabolism and kinetics of cerebral uptake of radioactive iodine labelled HIPDM were studied in vivo in rats to evaluate its potential usefulness for quantitative measurement of regional cerebral blood flow (rCBF). The results demonstrate that a method for quantitative measurement of rCBF with iodine labelled HIPDM must take into account its metabolic degradation, diffusion limitations, and bidirectional flux across the blood-brain barrier. Clinical studies have demonstrated that its intracerebral distribution, as assessed by single photon emission tomography (SPECT), reflects the distribution of rCBF. These observations suggest that this molecule might be of potential usefulness for quantitative rCBF measurement with SPECT. (author)

  15. Low-level electrical currents and brain indicators of behavioral activation

    Directory of Open Access Journals (Sweden)

    F. Lolas

    1977-12-01

    Full Text Available Distinguishing between slow brain potential correlates of arousal and activation on the basis of their functional role and temporal involvement during a reaction-time task, data are presented which suggest that weak electrical polarizing currents applied to the head in human subjects modify predominantly activation indicators rather than arousal ones.

  16. The potential of endogenous neurogenesis for brain repair and regeneration following traumatic brain injur y

    Institute of Scientific and Technical Information of China (English)

    Dong Sun

    2014-01-01

    Traumatic brain injury (TBI) is the leading cause of death and disability of persons under 45 years old in the United States, affecting over 1.5 million individuals each year. It had been th ought that recovery from such injuries is severely limited due to the inability of the adult bra in to replace damaged neurons. However, recent studies indicate that the mature mammalian central nervous system (CNS) has the potential to replenish damaged neurons by proliferation and neuronal differentiation of adult neural stem/progenitor cells residing in the neurogenic regions in the brain. Furthermore, increasing evidence indicates that these endogenous stem/progenitor cells may play regenerative and reparative roles in response to CNS injuries or diseases. In support of this notion, heightened levels of cell proliferation and neurogenesis have been ob-served in response to brain trauma or insults suggesting that the brain has the inherent potential to restore populations of damaged or destroyed neurons. This review will discuss the potential functions of adult neurogenesis and recent development of strategies aiming at harnessing this neurogenic capacity in order to repopulate and repair the injured brain.

  17. [Indications for studying evoked potentials in childhood. Methods--indications--value].

    Science.gov (United States)

    Görke, W

    1986-01-01

    Evoked potentials (EP) represent a valuable addition to currently applied diagnostic methods in neuropediatrics. Profound knowledge of the neurophysiological conditions producing EP-alterations allows basic conclusions, that cannot be gained or replaced by other investigations. EP-investigation demonstrate the existence but not the nature of a lesion in the CNS. Further diagnostic work-up usually will be necessary. Proved EP-alterations produce reproducible diagnostic results and give clues regarding its localization. Evoked potentials can be used as a screening-method for neuropediatric diseases. By follow-up examinations it is possible to show, wether there is progression or not. Testing for evoked potentials is indicated in suspected cerebral palsy in infants, in all cases of psychomotor retardation of unknown origin, impairment of vision or hearing, in cases of brain trauma or in suspected brainstem process, lesions of N. opticus or visual projective systems, neurometabolic or degenerative CNS disease, phacomatosis, progressive myoclonic epilepsy, ceroidlipofuscinosis Jansky-Bielschowski, benign partial epilepsy with extreme somatosensory evoked potentials, Ramsey-Hunt-Syndrome and aplasia of the corpus callosum.

  18. Animal imaging studies of potential brain damage

    Science.gov (United States)

    Gatley, S. J.; Vazquez, M. E.; Rice, O.

    To date, animal studies have not been able to predict the likelihood of problems in human neurological health due to HZE particle exposure during space missions outside the Earth's magnetosphere. In ongoing studies in mice, we have demonstrated that cocaine stimulated locomotor activity is reduced by a moderate dose (120 cGy) of 1 GeV 56Fe particles. We postulate that imaging experiments in animals may provide more sensitive and earlier indicators of damage due to HZE particles than behavioral tests. Since the small size of the mouse brain is not well suited to the spatial resolution offered by microPET, we are now repeating some of our studies in a rat model. We anticipate that this will enable us to identify imaging correlates of behavioral endpoints. A specific hypothesis of our studies is that changes in the metabolic rate for glucose in striatum of animals will be correlated with alterations in locomotor activity. We will also evaluate whether the neuroprotective drug L-deprenyl reduces the effect of radiation on locomotor activity. In addition, we will conduct microPET studies of brain monoamine oxidase A and monoamine oxidase B in rats before and at various times after irradiation with HZE particles. The hypothesis is that monoamine oxidase A, which is located in nerve terminals, will be unchanged or decreased after irradiation, while monoamine oxidase B, which is located in glial cells, will be increased after irradiation. Neurochemical effects that could be measured using PET could in principle be applied in astronauts, in terms of detecting and monitoring subtle neurological damage that might have occurred during long space missions. More speculative uses of PET are in screening candidates for prolonged space missions (for example, for adequate reserve in critical brain circuits) and in optimizing medications to treat impairments after missions.

  19. The potential of neural transplantation for brain repair and regeneration following traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    Dong Sun

    2016-01-01

    Traumatic brain injury is a major health problem worldwide. Currently, there is no effective treatment to improve neural structural repair and functional recovery of patients in the clinic. Cell transplantation is a potential strategy to repair and regenerate the injured brain. This review article summarized recent de-velopment in cell transplantation studies for post-traumatic brain injury brain repair with varying types of cell sources. It also discussed the potential of neural transplantation to repair/promote recovery of the injured brain following traumatic brain injury.

  20. Do resting brain dynamics predict oddball evoked-potential?

    Directory of Open Access Journals (Sweden)

    Lee Tien-Wen

    2011-11-01

    Full Text Available Abstract Background The oddball paradigm is widely applied to the investigation of cognitive function in neuroscience and in neuropsychiatry. Whether cortical oscillation in the resting state can predict the elicited oddball event-related potential (ERP is still not clear. This study explored the relationship between resting electroencephalography (EEG and oddball ERPs. The regional powers of 18 electrodes across delta, theta, alpha and beta frequencies were correlated with the amplitude and latency of N1, P2, N2 and P3 components of oddball ERPs. A multivariate analysis based on partial least squares (PLS was applied to further examine the spatial pattern revealed by multiple correlations. Results Higher synchronization in the resting state, especially at the alpha spectrum, is associated with higher neural responsiveness and faster neural propagation, as indicated by the higher amplitude change of N1/N2 and shorter latency of P2. None of the resting quantitative EEG indices predict P3 latency and amplitude. The PLS analysis confirms that the resting cortical dynamics which explains N1/N2 amplitude and P2 latency does not show regional specificity, indicating a global property of the brain. Conclusions This study differs from previous approaches by relating dynamics in the resting state to neural responsiveness in the activation state. Our analyses suggest that the neural characteristics carried by resting brain dynamics modulate the earlier/automatic stage of target detection.

  1. INDICATORS OF ESTIMATION THE SERVICE INDUSTRIES' MARKETING POTENTIAL

    OpenAIRE

    Iarmosh, O.

    2015-01-01

    The purpose of the article is to examine the indicators of marketing potential’s evaluation for various enterprises and to analyze them for the commodity production enterprises and service sector. The contents of the enterprise’s marketing potential, the factors that form its structure are considered in the article. It’s analyzed the indicators impact, both instrumental and organizational components, on the marketing potential values for commodity production and service industries, working on...

  2. Selective oestrogen receptor modulators differentially potentiate brain mitochondrial function.

    Science.gov (United States)

    Irwin, R W; Yao, J; To, J; Hamilton, R T; Cadenas, E; Brinton, R D

    2012-01-01

    The mitochondrial energy-transducing capacity of the brain is important for long-term neurological health and is influenced by endocrine hormone responsiveness. The present study aimed to determine the role of oestrogen receptor (ER) subtypes in regulating mitochondrial function using selective agonists for ERα (propylpyrazoletriol; PPT) and ERβ (diarylpropionitrile; DPN). Ovariectomised female rats were treated with 17β-oestradiol (E(2) ), PPT, DPN or vehicle control. Both ER selective agonists significantly increased the mitochondrial respiratory control ratio and cytochrome oxidase (COX) activity relative to vehicle. Western blots of purified whole brain mitochondria detected ERα and, to a greater extent, ERβ localisation. Pre-treatment with DPN, an ERβ agonist, significantly increased ERβ association with mitochondria. In the hippocampus, DPN activated mitochondrial DNA-encoded COX I expression, whereas PPT was ineffective, indicating that mechanistically ERβ, and not ERα, activated mitochondrial transcriptional machinery. Both selective ER agonists increased protein expression of nuclear DNA-encoded COX IV, suggesting that activation of ERβ or ERα is sufficient. Selective ER agonists up-regulated a panel of bioenergetic enzymes and antioxidant defence proteins. Up-regulated proteins included pyruvate dehydrogenase, ATP synthase, manganese superoxide dismutase and peroxiredoxin V. In vitro, whole cell metabolism was assessed in live primary cultured hippocampal neurones and mixed glia. The results of analyses conducted in vitro were consistent with data obtained in vivo. Furthermore, lipid peroxides, accumulated as a result of hormone deprivation, were significantly reduced by E(2) , PPT and DPN. These findings suggest that the activation of both ERα and ERβ is differentially required to potentiate mitochondrial function in brain. As active components in hormone therapy, synthetically designed oestrogens as well as natural phyto-oestrogen cocktails

  3. Brain Event-Related Potential Correlates of Concept Learning.

    Science.gov (United States)

    Federico, Pat-Anthony

    An irrelevant auditory probe procedure was used to evoke brain event-related potentials (ERPs) in 56 Navy recruits while they learned pulsed radar concepts presented to them in study booklets. A mastery test was administered to assess concept acquisition. The research issue was whether brain ERPs recorded while students are in the process of…

  4. Brain potentials to inflected adjectives: beyond storage and decomposition.

    Science.gov (United States)

    Leminen, Alina; Clahsen, Harald

    2014-01-16

    This study uses event-related brain potentials (ERPs) to investigate the temporal sequencing of structural (grammatical) and lexical (semantic) properties of complex words during language comprehension. Morphologically complex words do not only consist of stems and affixes (e.g., 'feel'+'-s'), but affixes also contain grammatical structure, viz. feature bundles specifying their morpho-syntactic functions (e.g., -s= [3rd person, singular, present tense]). We examined inflected adjectives of German, which consist of an unaltered stem plus a portmanteau affix encoding case, number and gender. The same group of 24 adult native speakers was tested in two cross-modal ERP priming experiments separately studying effects of lexical-semantic relatedness and related affixes. The results of these experiments revealed clearly distinct brain potentials. Prime-target overlap with respect to morpho-syntactic features was associated with a reduced positivity, whereas lexical-level priming led to a reduced negativity. The former was most pronounced between 200 and 300 ms and the latter in a later time window, between 300 and 400 ms. We interpret the reduced early positivity as reflecting ease of grammatical processing effort in case of primed (relative to unprimed) morpho-syntactic features and the reduced negativity as signaling facilitation in lexical retrieval for primed (compared to unprimed) words. Our ERP results indicate that grammatical information becomes available earlier than semantic information providing support for structure-first models of language processing. PMID:24161829

  5. Brain potentials to inflected adjectives: beyond storage and decomposition.

    Science.gov (United States)

    Leminen, Alina; Clahsen, Harald

    2014-01-16

    This study uses event-related brain potentials (ERPs) to investigate the temporal sequencing of structural (grammatical) and lexical (semantic) properties of complex words during language comprehension. Morphologically complex words do not only consist of stems and affixes (e.g., 'feel'+'-s'), but affixes also contain grammatical structure, viz. feature bundles specifying their morpho-syntactic functions (e.g., -s= [3rd person, singular, present tense]). We examined inflected adjectives of German, which consist of an unaltered stem plus a portmanteau affix encoding case, number and gender. The same group of 24 adult native speakers was tested in two cross-modal ERP priming experiments separately studying effects of lexical-semantic relatedness and related affixes. The results of these experiments revealed clearly distinct brain potentials. Prime-target overlap with respect to morpho-syntactic features was associated with a reduced positivity, whereas lexical-level priming led to a reduced negativity. The former was most pronounced between 200 and 300 ms and the latter in a later time window, between 300 and 400 ms. We interpret the reduced early positivity as reflecting ease of grammatical processing effort in case of primed (relative to unprimed) morpho-syntactic features and the reduced negativity as signaling facilitation in lexical retrieval for primed (compared to unprimed) words. Our ERP results indicate that grammatical information becomes available earlier than semantic information providing support for structure-first models of language processing.

  6. The potential of using brain images for authentication.

    Science.gov (United States)

    Chen, Fanglin; Zhou, Zongtan; Shen, Hui; Hu, Dewen

    2014-01-01

    Biometric recognition (also known as biometrics) refers to the automated recognition of individuals based on their biological or behavioral traits. Examples of biometric traits include fingerprint, palmprint, iris, and face. The brain is the most important and complex organ in the human body. Can it be used as a biometric trait? In this study, we analyze the uniqueness of the brain and try to use the brain for identity authentication. The proposed brain-based verification system operates in two stages: gray matter extraction and gray matter matching. A modified brain segmentation algorithm is implemented for extracting gray matter from an input brain image. Then, an alignment-based matching algorithm is developed for brain matching. Experimental results on two data sets show that the proposed brain recognition system meets the high accuracy requirement of identity authentication. Though currently the acquisition of the brain is still time consuming and expensive, brain images are highly unique and have the potential possibility for authentication in view of pattern recognition. PMID:25126604

  7. Quercetin in brain diseases: Potential and limits.

    Science.gov (United States)

    Dajas, Federico; Abin-Carriquiry, Juan Andrés; Arredondo, Florencia; Blasina, Fernanda; Echeverry, Carolina; Martínez, Marcela; Rivera, Felicia; Vaamonde, Lucía

    2015-10-01

    Quercetin is a ubiquitous flavonoid present in beverages, food and plants that has been demonstrated to have a role in the prevention of neurodegenerative and cerebrovascular diseases. In neuronal culture, quercetin increases survival against oxidative insults. Antioxidation appears to be a necessary but not sufficient condition for its neuroprotective action and modulation of intracellular signaling and transcription factors, increasing the expression of antioxidant and pro survival proteins and modulating inflammation, appears as important for neuronal protection. Quercetin also regulates the activity of kinases, changing the phosphorylation state of target molecules, resulting in modulation of cellular function and gene expression. Concentrations of quercetin higher than 100 μM consistently show cytotoxic and apoptotic effects by its autoxidation and generation of toxic quinones. In vivo, results are controversial with some studies showing neuroprotection by quercetin and others not, requiring a drug delivery system or chronic treatments to show neuroprotective effects. The blood and brain bioavailability of free quercetin after ingestion is a complex and controversial process that produces final low concentrations, a fact that has led to suggestions that metabolites would be active by themselves and/or as pro-drugs that would release the active aglycone in the brain. Available studies show that in normal or low oxidative conditions, chronic treatments with quercetin contributes to re-establish the redox regulation of proteins, transcription factors and survival signaling cascades that promote survival. In the presence of highly oxidative conditions such as in an ischemic tissue, quercetin could become pro-oxidant and toxic. At present, evidence points to quercetin as a preventive molecule for neuropathology when administered in natural matrices such as vegetables and food. More research is needed to support its use as a lead compound in its free form in

  8. Educational games for brain health: revealing their unexplored potential through a neurocognitive approach

    Directory of Open Access Journals (Sweden)

    Patrick eFissler

    2015-07-01

    Full Text Available Educational games link the motivational nature of games with learning of knowledge and skills. Here, we go beyond effects on these learning outcomes. We review two lines of evidence which indicate the currently unexplored potential of educational games to promote brain health: First, gaming with specific neurocognitive demands (e.g., executive control, and second, educational learning experiences (e.g., studying foreign languages improve brain health markers. These markers include cognitive ability, brain function, and brain structure. As educational games allow the combination of specific neurocognitive demands with educational learning experiences, they seem to be optimally suited for promoting brain health. We propose a neurocognitive approach to reveal this unexplored potential of educational games in future research.

  9. Educational games for brain health: revealing their unexplored potential through a neurocognitive approach.

    Science.gov (United States)

    Fissler, Patrick; Kolassa, Iris-Tatjana; Schrader, Claudia

    2015-01-01

    Educational games link the motivational nature of games with learning of knowledge and skills. Here, we go beyond effects on these learning outcomes. We review two lines of evidence which indicate the currently unexplored potential of educational games to promote brain health: First, gaming with specific neurocognitive demands (e.g., executive control), and second, educational learning experiences (e.g., studying foreign languages) improve brain health markers. These markers include cognitive ability, brain function, and brain structure. As educational games allow the combination of specific neurocognitive demands with educational learning experiences, they seem to be optimally suited for promoting brain health. We propose a neurocognitive approach to reveal this unexplored potential of educational games in future research. PMID:26257697

  10. Educational games for brain health: revealing their unexplored potential through a neurocognitive approach

    OpenAIRE

    Patrick eFissler; Iris-Tatjana eKolassa; Claudia eSchrader

    2015-01-01

    Educational games link the motivational nature of games with learning of knowledge and skills. Here, we go beyond effects on these learning outcomes. We review two lines of evidence which indicate the currently unexplored potential of educational games to promote brain health: First, gaming with specific neurocognitive demands (e.g., executive control), and second, educational learning experiences (e.g., studying foreign languages) improve brain health markers. These markers include cognitive...

  11. Brain potential changes in voluntary and passive movements in humans: readiness potential and reafferent potentials.

    Science.gov (United States)

    Kornhuber, Hans H; Deecke, Lüder

    2016-07-01

    A method of chronological data storage and reverse computation is described by which bio-electrical phenomena preceding 'spontaneous' events within the nervous system can be analysed if these events appear repeatedly and are capable of triggering a computer.Slow brain potentials accompanying voluntary and passive movements of the limbs were analysed by this method. These potentials were recorded from different points of the scalp from 12 healthy subjects in 94 experiments with more than 100 movements in each record. At times artifacts were superimposed upon cerebral potentials. The former were identified, and, as far as possible, eliminated.Voluntary hand or foot movements are preceded by a slowly increasing surface-negative cortical potential of 10-15 μV, called readiness potential. This potential is maximal over the contralateral precentral region, but shows bilateral spread and is larger over the frontal than over the occipital areas. The readiness potential increases with intentional engagement and is reduced by mental indifference of the subject.Voluntary movements are followed by a complex potential with an early positive phase that begins 30-90 msec after the onset of movement. The late potentials following voluntary movements are similar to those after passive movements. Both resemble the late bilateral components of the evoked potentials after electrical stimulation of peripheral nerves. Some variable differences between the early components of the potentials after the onset of active and passive movements require further investigation.No relation between the onset of voluntary movements and the phase of the alpha rhythm could be detected.Further applications of reverse computation are addressed. Similarities between the readiness potential and G. WALTER'S expectancy wave in conditioned reflexes, and the sources of artifacts through eye movements etc. are discussed. PMID:27392465

  12. Potential of solid lipid nanoparticles in brain targeting.

    Science.gov (United States)

    Kaur, Indu Pal; Bhandari, Rohit; Bhandari, Swati; Kakkar, Vandita

    2008-04-21

    Brain is a delicate organ, isolated from general circulation and characterized by the presence of relatively impermeable endothelial cells with tight junctions, enzymatic activity and the presence of active efflux transporter mechanisms (like P-gp efflux). These formidable obstacles often impede drug delivery to the brain. As a result several promising molecules (showing a good potential in in vitro evaluation) are lost from the market for a mere consequence of lack of in vivo response probably because the molecule cannot reach the brain in a sufficient concentration. The options to tailor make molecules for brain, though open to the medical chemist, are a costly proposition in terms of money, manpower and time (almost 50 years). The premedial existing approaches for brain delivery like superficial and ventricular application of chemical or the application of chemicals to brain parenchyma are invasive and hence are less patient friendly, more laborious and require skill and could also damage the brain permanently. In view of these considerations novel drug delivery systems such as the nanoparticles are presently being explored for their suitability for targeted brain delivery. Nanoparticles are solid colloidal particles ranging in size from 1 to 1000 nm (<1 microm) and composed of macromolecular material. Nanoparticles could be polymeric or lipidic (SLNs). SLNs are taken up readily by the brain because of their lipidic nature. The bioacceptable and biodegradable nature of SLNs makes them less toxic as compared to polymeric nanoparticles. Supplemented with small size which prolongs the circulation time in blood, feasible scale up for large scale production and absence of burst effect makes them interesting candidates for study. In the present review we will discuss about the barriers to CNS drug delivery, strategies to bypass the blood-brain barrier and characterization methods of SLNs and their usefulness. The proposed mechanism of uptake, methods of prolonging the

  13. Potential of Nonlinear Ultrasonic Indicators for Nondestructive Testing of Concrete

    Directory of Open Access Journals (Sweden)

    C. Payan

    2010-01-01

    Full Text Available In the context of a growing need for safety and reliability in Civil Engineering, acoustic methods of nondestructive testing provide answers to a real industrial need. Linear indicators (wave speed and attenuation exhibit a limited sensitivity, unlike nonlinear ones which usually have a far greater dynamic range. This paper illustrates the potential of these indicators, and evaluates its potential for in situ applications. Concrete, a structurally heterogeneous and volumetrically, mechanically damaged material, is an example of a class of materials that exhibit strong multiple scattering as well as significant elastic nonlinear response. In the context of stress monitoring in pre-stressed structures, we show that intense scattering can be applied to robustly determine velocity changes at progressively increasing applied stress using coda wave interferometry and thereby extract nonlinear coefficients. In a second part, we demonstrate the high sensitivity of nonlinear parameters to thermal damage as regard with linear ones. Then, the influence of water content and porosity on these indicators is quantified allowing to uncouple the effect of damage from environmental or structural parameters.

  14. Scale-Free Brain Networks Based on the Event-Related Potential during Visual Spatial Attention

    Institute of Scientific and Technical Information of China (English)

    LI Ling; JIN Zhen-Lan

    2011-01-01

    @@ The human brain is thought of as one of the most complex dynamical systems in the universe.The network view of the dynamical system has emerged since the discovery of scale-free networks.Brain functional networks, which represent functional associations among brain regions, are extracted by measuring the temporal correlations from electroencephalogram data.We measure the topological properties of the brain functional network, including degree distribution, average degree, clustering coefficient and the shortest path length, to compare the networks of multi-channel event-related potential activity between visual spatial attention and unattention conditions.It is found that the degree distribution of the brain functional networks under both the conditions is a power law distribution, which reflects a scale-free property.Moreover, the scaling exponent of the attention condition is significantly smaller than that of the unattention condition.However, the degree distribution of equivalent random networks does not follow the power law distribution.In addition, the clustering coefficient of these random networks is smaller than those of brain networks, and the shortest path length of these random networks is large and comparable with those of brain networks.Our results, typical of scale-free networks, indicate that the scaling exponent of brain activity could reflect different cognitive processes.%The human brain is thought of as one of the most complex dynamical systems in the universe. The network view of the dynamical system has emerged since the discovery of scale-free networks. Brain functional networks, which represent functional associations among brain regions, are extracted by measuring the temporal correlations from electroencephalogram data. We measure the topological properties of the brain functional network, including degree distribution, average degree, clustering coefficient and the shortest path length, to compare the networks of multi-channel event

  15. Decade of the Brain 1990--2000: Maximizing human potential

    Energy Technology Data Exchange (ETDEWEB)

    1991-04-01

    The US Decade of the Brain offers scientists throughout the Federal Government a unique opportunity to advance and apply scientific knowledge about the brain and nervous system. During the next 10 years, scientists hope to maximize human potential through studies of human behavior, senses and communication, learning and memory, genetic/chemical alterations, and environmental interactions. Progress in these areas should lead to reductions in mortality from brain and nervous system disorders and to improvements in the quality of life. This report identifies nine research areas that could form the basis of an integrated program in the brain and behavioral sciences. A chart summarizing the Federal activities in these nine areas may be found at the back of the report. In addition, three areas that span the nine research areas -- basic research, technology and international activities -- are considered.

  16. Potentials for Soil Enzyme as Indicators of Ecological Management

    Science.gov (United States)

    Senwo, Z. N.; Manu, A.; Coleman, T. L.

    1997-01-01

    Activity measurements of selected soil enzymes (cellulase, glucosidase, amidohydrolase, phosphatase, arylsulfatase) involved in carbon, nitrogen, phosphorus, and sulfur cycling in the biosphere, hold potential as early and sensitive indicators of soil ecological stress and restoration, These measurements are advantageous because the procedures are simple, rapid, and reproducible over time. Enzyme activities are sensitive to short-term changes in soil and kind-use management. Enzyme activities have also been observed to be closely related to soil organic matter proposed as an index of soil quality.

  17. 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...

  18. Therapeutic Potential of Curcumin for the Treatment of Brain Tumors

    Science.gov (United States)

    Klinger, Neil V.

    2016-01-01

    Brain malignancies currently carry a poor prognosis despite the current multimodal standard of care that includes surgical resection and adjuvant chemotherapy and radiation. As new therapies are desperately needed, naturally occurring chemical compounds have been studied for their potential chemotherapeutic benefits and low toxicity profile. Curcumin, found in the rhizome of turmeric, has extensive therapeutic promise via its antioxidant, anti-inflammatory, and antiproliferative properties. Preclinical in vitro and in vivo data have shown it to be an effective treatment for brain tumors including glioblastoma multiforme. These effects are potentiated by curcumin's ability to induce G2/M cell cycle arrest, activation of apoptotic pathways, induction of autophagy, disruption of molecular signaling, inhibition of invasion, and metastasis and by increasing the efficacy of existing chemotherapeutics. Further, clinical data suggest that it has low toxicity in humans even at large doses. Curcumin is a promising nutraceutical compound that should be evaluated in clinical trials for the treatment of human brain tumors.

  19. 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

  20. An abnormal resting-state functional brain network indicates progression towards Alzheimer’s disease*****

    Institute of Scientific and Technical Information of China (English)

    Jie Xiang; Hao Guo; Rui Cao; Hong Liang; Junjie Chen

    2013-01-01

    Brain structure and cognitive function change in the temporal lobe, hippocampus, and prefrontal cortex of patients with mild cognitive impairment and Alzheimer’s disease, and brain network-connection strength, network efficiency, and nodal attributes are abnormal. However, existing research has only analyzed the differences between these patients and normal controls. In this study, we constructed brain networks using resting-state functional MRI data that was extracted from four populations mal controls, patients with early mild cognitive impairment, patients with late mild cognitive impairment, and patients with Alzheimer’s disease) using the Alzheimer’s Disease Neuroimaging Initiative data set. The aim was to analyze the characteristics of resting-state functional neural networks, and to observe mild cognitive impairment at different stages before the transformation to Alzheimer’s disease. Results showed that as cognitive deficits increased across the four groups, the shortest path in the rest-ing-state functional network gradual y increased, while clustering coefficients gradual y decreased. This evidence indicates that dementia is associated with a decline of brain network efficiency. In tion, the changes in functional networks revealed the progressive deterioration of network function across brain regions from healthy elderly adults to those with mild cognitive impairment and Alzhei-mer’s disease. The alterations of node attributes in brain regions may reflect the cognitive functions in brain regions, and we speculate that early impairments in memory, hearing, and language function can eventual y lead to diffuse brain injury and other cognitive impairments.

  1. Anaphoric Reference to Quantified Antecedents: An Event-Related Brain Potential Study

    Science.gov (United States)

    Filik, Ruth; Leuthold, Hartmut; Moxey, Linda M.; Sanford, Anthony J.

    2011-01-01

    We report an event-related brain potential (ERP) study examining how readers process sentences containing anaphoric reference to quantified antecedents. Previous studies indicate that positive (e.g. "many") and negative (e.g. "not many") quantifiers cause readers to focus on different sets of entities. For example in "Many of the fans attended the…

  2. Scale-Free Brain Networks Based on the Event-Related Potential during Visual Spatial Attention

    Science.gov (United States)

    Li, Ling; Jin, Zhen-Lan

    2011-04-01

    The human brain is thought of as one of the most complex dynamical systems in the universe. The network view of the dynamical system has emerged since the discovery of scale-free networks. Brain functional networks, which represent functional associations among brain regions, are extracted by measuring the temporal correlations from electroencephalogram data. We measure the topological properties of the brain functional network, including degree distribution, average degree, clustering coefficient and the shortest path length, to compare the networks of multi-channel event-related potential activity between visual spatial attention and unattention conditions. It is found that the degree distribution of the brain functional networks under both the conditions is a power law distribution, which reflects a scale-free property. Moreover, the scaling exponent of the attention condition is significantly smaller than that of the unattention condition. However, the degree distribution of equivalent random networks does not follow the power law distribution. In addition, the clustering coefficient of these random networks is smaller than those of brain networks, and the shortest path length of these random networks is large and comparable with those of brain networks. Our results, typical of scale-free networks, indicate that the scaling exponent of brain activity could reflect different cognitive processes.

  3. Prognostic indices in stereotactic radiotherapy of brain metastases of non-small cell lung cancer

    International Nuclear Information System (INIS)

    Our purpose was to analyze the long-term clinical outcome and to identify prognostic factors after Linac-based stereotactic radiosurgery (SRS) or fractionated stereotactic radiotherapy (FSRT) on patients with brain metastases (BM) from non-small cell lung cancer (NSCLC). We performed a retrospective analysis of survival on 90 patients who underwent SRS or FSRT of intracranial NSCLC metastases between 04/2004 and 05/2014 that had not undergone prior surgery or whole brain radiotherapy (WBRT) for BM. Follow-up data was analyzed until May 2015. Potential prognostic factors were examined in univariable and multivariable analyses. The Golden Grading System (GGS), the disease-specific graded prognostic assessment (DS-GPA), the RADES II prognostic index as well as the NSCLC-specific index proposed by Rades et al. in 2013 (NSCLC-RADES) were calculated and their predictive values were tested in univariable analysis. The median follow-up time of the surviving patients was 14 months. The overall survival (OS) rate was 51 % after 6 months and 29.9 % after 12 months. Statistically significant factors of better OS after univariable analysis were lower International Union Against Cancer (UICC) stage at first diagnosis, histology of adenocarcinoma, prior surgery of the primary tumor and lower total BM volume. After multivariable analysis adenocarcinoma histology remained a significant factor; higher Karnofsky Performance Score (KPS) and the presence of extracranial metastases (ECM) were also significant. The RADES II and the NSCLC-RADES indices were significant predictors of OS. However, the NSCLC-RADES failed to differentiate between intermediate- and low-risk patients. The DS-GPA and GGS were not statistically significant predictors of survival in univariable analysis. The ideal prognostic index has not been defined yet. We believe that more specific indices will be developed in the future. Our results indicate that the histologic subtype of NSCLC could add to the prognostic

  4. Therapeutic Potential of Curcumin for the Treatment of Brain Tumors

    Directory of Open Access Journals (Sweden)

    Neil V. Klinger

    2016-01-01

    Full Text Available Brain malignancies currently carry a poor prognosis despite the current multimodal standard of care that includes surgical resection and adjuvant chemotherapy and radiation. As new therapies are desperately needed, naturally occurring chemical compounds have been studied for their potential chemotherapeutic benefits and low toxicity profile. Curcumin, found in the rhizome of turmeric, has extensive therapeutic promise via its antioxidant, anti-inflammatory, and antiproliferative properties. Preclinical in vitro and in vivo data have shown it to be an effective treatment for brain tumors including glioblastoma multiforme. These effects are potentiated by curcumin’s ability to induce G2/M cell cycle arrest, activation of apoptotic pathways, induction of autophagy, disruption of molecular signaling, inhibition of invasion, and metastasis and by increasing the efficacy of existing chemotherapeutics. Further, clinical data suggest that it has low toxicity in humans even at large doses. Curcumin is a promising nutraceutical compound that should be evaluated in clinical trials for the treatment of human brain tumors.

  5. 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

  6. Potential pressure indicators for fishing, and their data requirements

    NARCIS (Netherlands)

    Piet, G.J.; Quirijns, F.J.; Robinson, L.; Greenstreet, S.P.R.

    2007-01-01

    Indicators of fishing pressure are necessary to support an ecosystem approach to fisheries management (EAFM). We present a framework that distinguishes four levels of pressure indicators that move from being a simple description of anthropogenic activity to more precisely describing the actual press

  7. Dissociation of Category-Learning Systems via Brain Potentials

    Directory of Open Access Journals (Sweden)

    Robert G Morrison

    2015-07-01

    Full Text Available Behavioral, neuropsychological, and neuroimaging evidence has suggested that categories can often be learned via either an explicit rule-based mechanism critically dependent on medial temporal and prefrontal brain regions, or via an implicit information-integration mechanism relying on the basal ganglia. In this study, participants viewed sine-wave gratings (i.e., Gabor patches that varied on two dimensions and learned to categorize them via trial-by-trial feedback. Two different stimulus distributions were used; one was intended to encourage an explicit rule-based process and the other an implicit information-integration process. We monitored brain activity with scalp electroencephalography (EEG while each participant (1 passively observed stimuli represented of both distributions, (2 categorized stimuli from one distribution, and, one week later, (3 categorized stimuli from the other distribution. Categorization accuracy was similar for the two distributions. Subtractions of Event-Related Potentials (ERPs for correct and incorrect trials were used to identify neural differences in rule-based and information-integration categorization processes. We identified an occipital brain potential that was differentially modulated by categorization condition accuracy at an early latency (150 - 250 ms, likely reflecting the degree of holistic processing. A stimulus-locked late positive complex associated with explicit memory updating was modulated by accuracy in the rule-based, but not the information-integration task. Likewise, a feedback-locked P300 ERP associated with expectancy was correlated with performance only in the rule-based, but not the information-integration condition. These results provide additional evidence for distinct brain mechanisms supporting rule-based versus implicit information-integration category learning and use.

  8. Seagrass epiphytes: useful indicator, potential biological criterion, or forlorn hope?

    Science.gov (United States)

    Epiphytes on seagrasses have been studied for more than 50 years, and proposed as an indicator of anthropogenic nutrient enrichment for over 30 years. Epiphytes have been correlated with seagrass declines, causally related to nutrient additions in both field and mesocosm experim...

  9. AN INDICATOR OF POTENTIAL STREAM WOOD CONTRIBUTION FOR RIPARIAN FORESTS

    Science.gov (United States)

    In northwestern Oregon a key function of riparian forests is to provide wood to the stream network. This function is a prominent feature of Federal and State forest practices in the region. Thus, defining indicators which are associated with this function are important for desi...

  10. Correlating learning and memory improvements to long-term potentiation in patients with brain injury

    Institute of Scientific and Technical Information of China (English)

    Xingfu Peng; Qian Yu

    2008-01-01

    BACKGROUND:Brain injury patients often exhibit learning and memory functional deficits.Long-term potentiation(LTP)is a representative index for studying learning and memory cellular models; the LTP index correlates to neural plasticity. OBJECTIVE:This study was designed to investigate correlations of learning and memory functions to LTP in brain injury patients,and to summarize the research advancements in mechanisms underlying brain functional improvements after rehabilitation intervention. RETRIEVAL STRATEGY:Using the terms "brain injuries,rehabilitation,learning and memory,long-term potentiation",manuscripts that were published from 2000-2007 were retrieved from the PubMed database.At the same time,manuscripts published from 2000-2007 were also retrieved from the Database of Chinese Scientific and Technical Periodicals with the same terms in the Chinese language.A total of 64 manuscripts were obtained and primarily screened.Inclusion criteria:studies on learning and memory,as well as LTP in brain injury patients,and studies focused on the effects of rehabilitation intervention on the two indices; studies that were recently published or in high-impact journals.Exclusion criteria:repetitive studies.LITERATURE EVALUATION:The included manuscripts primarily focused on correlations between learning and memory and LTP,the effects of brain injury on learning and memory,as well as LTP,and the effects of rehabilitation intervention on learning and memory after brain injury.The included 39 manuscripts were clinical,basic experimental,or review studies. DATA SYNTHESIS:Learning and memory closely correlates to LTP.The neurobiological basis of learning and memory is central nervous system plasticity,which involves neural networks,neural circuits,and synaptic connections,in particular,synaptic plasticity.LTP is considered to be an ideal model for studying synaptic plasticity,and it is also a classic model for studying neural plasticity of learning and memory.Brain injury

  11. Indications for brain CT scan in patients with minor head injury

    OpenAIRE

    M Saboori; J Ahmadi

    2006-01-01

    BACKGROUND: Minor head injury is the most common type of head injury. Despite its high prevalence and a lot of studies, there is much controversies about the management of these patients. We performed this study to find indications for brain CT scan according to clinical signs and symptoms. METHODS: We did this prospective cohort study in two university hospitals (Alzahra and Kashani) for one year enrolling 682 consecutive patients with minor head injury (GCS = 15) and recording all clin...

  12. Auditory event-related brain potentials for an early discrimination between normal and pathological brain aging

    Institute of Scientific and Technical Information of China (English)

    Juliana Dushanova; Mario Christov

    2013-01-01

    The brain as a system with gradually decreasing resources maximizes its chances by reorganizing neural networks to ensure efficient performance. Auditory event-related potentials were recorded in 28 healthy volunteers comprising 14 young and 14 elderly subjects in auditory discrimination motor task (low frequency tone – right hand movement and high frequency tone – left hand movement). The amplitudes of the sensory event-related potential components (N1, P2) were more pronounced with increasing age for either tone and this effect for P2 amplitude was more pronounced in the frontal region. The latency relationship of N1 between the groups was tone-dependent, while that of P2 was tone-independent with a prominent delay in the elderly group over all brain regions. The amplitudes of the cognitive components (N2, P3) diminished with increasing age and the hemispheric asymmetry of N2 (but not for P3) reduced with increasing age. Prolonged N2 latency with increasing age was widespread for either tone while between-group difference in P3 latency was tone-dependent. High frequency tone stimulation and movement requirements lead to P3 delay in the elderly group. The amplitude difference of the sensory components between the age groups could be due to a general greater alertness, less expressed habituation, or decline in the ability to retreat attentional resources from the stimuli in the elderly group. With aging, a neural circuit reorganization of the brain activity affects the cognitive processes. The approach used in this study is useful for an early discrimination between normal and pathological brain aging for early treatment of cognitive alterations and dementia.

  13. Fetal functional brain age assessed from universal developmental indices obtained from neuro-vegetative activity patterns.

    Directory of Open Access Journals (Sweden)

    Dirk Hoyer

    Full Text Available Fetal brain development involves the development of the neuro-vegetative (autonomic control that is mediated by the autonomic nervous system (ANS. Disturbances of the fetal brain development have implications for diseases in later postnatal life. In that context, the fetal functional brain age can be altered. Universal principles of developmental biology applied to patterns of autonomic control may allow a functional age assessment. The work aims at the development of a fetal autonomic brain age score (fABAS based on heart rate patterns. We analysed n = 113 recordings in quiet sleep, n = 286 in active sleep, and n = 29 in active awakeness from normals. We estimated fABAS from magnetocardiographic recordings (21.4-40.3 weeks of gestation preclassified in quiet sleep (n = 113, 63 females and active sleep (n = 286, 145 females state by cross-validated multivariate linear regression models in a cross-sectional study. According to universal system developmental principles, we included indices that address increasing fluctuation range, increasing complexity, and pattern formation (skewness, power spectral ratio VLF/LF, pNN5. The resulting models constituted fABAS. fABAS explained 66/63% (coefficient of determination R(2 of training and validation set of the variance by age in quiet, while 51/50% in active sleep. By means of a logistic regression model using fluctuation range and fetal age, quiet and active sleep were automatically reclassified (94.3/93.1% correct classifications. We did not find relevant gender differences. We conclude that functional brain age can be assessed based on universal developmental indices obtained from autonomic control patterns. fABAS reflect normal complex functional brain maturation. The presented normative data are supplemented by an explorative study of 19 fetuses compromised by intrauterine growth restriction. We observed a shift in the state distribution towards active awakeness. The lower WGA

  14. Biologically controlled minerals as potential indicators of life

    Science.gov (United States)

    Schwartz, D. E.; Mancinelli, R. L.; Kaneshiro, E.

    1991-01-01

    Minerals can be produced and deposited either by abiotic or biologic means. Regardless of their origin, mineral crystals reflect the environment conditions (e.g., temperature, pressure, chemical composition, and redox potential) present during crystal formation. Biologically-produced mineral crystals are grown or reworked under the control of their host organism and reflect an environment different from the abiotic environment. In addition, minerals of either biologic or abiotic origin have great longevities. For these reasons, biologically produced minerals have been proposed as biomarkers. Biomarkers are key morphological, chemical, and isotopic signatures of living systems that can be used to determine if life processes have occurred. Studies of biologically controlled minerals produced by the protist, Paramecium tetraurelia, were initiated since techniques have already been developed to culture them and isolate their crystalline material, and methods are already in place to analyze this material. Two direct crystalline phases were identified. One phase, whose chemical composition is high in Mg, was identified as struvite. The second phase, whose chemical composition is high in Ca, has not been previously found occurring naturally and may be considered a newly discovered material. Analyses are underway to determine the characteristics of these minerals in order to compare them with characteristics of these minerals in order to compare them with characteristics of minerals formed abiotically, but with the same chemical composition.

  15. [The transition of deep brain stimulation from disease specific to symptom specific indications].

    Science.gov (United States)

    Okun, Michael S

    2012-01-01

    The success of chronic deep brain stimulation (DBS) and electrical neuro-network modulation (ENM) to address neurological and neuropsychiatric disorders has led the Food and Drug Administration (FDA), and also other worldwide regulatory agencies to grant approval for the use of DBS in specific disorders. In the United States, DBS is FDA approved for the treatment of advanced Parkinson's disease (PD), essential tremor (ET), obsessive compulsive disorder (OCD), and for dystonia. OCD and dystonia have been approved under a mechanism referred to as a humanitarian device exemption (HDE). However, as the field of DBS and ENM evolve there has been a shift in practice patterns from targeting diseases to targeting specific and disabling symptoms. This shift has been driving interdisciplinary DBS boards to collect, and to address symptom profiles in all potential DBS candidates. Based on a specific symptom profile, a strategic and personalized medicine approach can be undertaken. The personalized approach will take into consideration the brain target, a unilateral versus a bilateral procedure, and the potential for use of more than one DBS lead per brain hemisphere. Additionally, a personalized approach to DBS will also facilitate improved pre-operative medication adjustments, as well as optimal post-operative medication, behavioral, and device management. PMID:23196455

  16. Mapping neuroplastic potential in brain-damaged patients.

    Science.gov (United States)

    Herbet, Guillaume; Maheu, Maxime; Costi, Emanuele; Lafargue, Gilles; Duffau, Hugues

    2016-03-01

    It is increasingly acknowledged that the brain is highly plastic. However, the anatomic factors governing the potential for neuroplasticity have hardly been investigated. To bridge this knowledge gap, we generated a probabilistic atlas of functional plasticity derived from both anatomic magnetic resonance imaging results and intraoperative mapping data on 231 patients having undergone surgery for diffuse, low-grade glioma. The atlas includes detailed level of confidence information and is supplemented with a series of comprehensive, connectivity-based cluster analyses. Our results show that cortical plasticity is generally high in the cortex (except in primary unimodal areas and in a small set of neural hubs) and rather low in connective tracts (especially associative and projection tracts). The atlas sheds new light on the topological organization of critical neural systems and may also be useful in predicting the likelihood of recovery (as a function of lesion topology) in various neuropathological conditions-a crucial factor in improving the care of brain-damaged patients. PMID:26912646

  17. Quantitative Susceptibility Mapping Indicates a Disturbed Brain Iron Homeostasis in Neuromyelitis Optica – A Pilot Study

    Science.gov (United States)

    Granado, Vanessa; Rueda, Fernanda; Deistung, Andreas; Reichenbach, Juergen R.; Tukamoto, Gustavo; Gasparetto, Emerson Leandro; Schweser, Ferdinand

    2016-01-01

    Dysregulation of brain iron homeostasis is a hallmark of many neurodegenerative diseases and can be associated with oxidative stress. The objective of this study was to investigate brain iron in patients with Neuromyelitis Optica (NMO) using quantitative susceptibility mapping (QSM), a quantitative iron-sensitive MRI technique. 12 clinically confirmed NMO patients (6 female and 6 male; age 35.4y±14.2y) and 12 age- and sex-matched healthy controls (7 female and 5 male; age 33.9±11.3y) underwent MRI of the brain at 3 Tesla. Quantitative maps of the effective transverse relaxation rate (R2*) and magnetic susceptibility were calculated and a blinded ROI-based group comparison analysis was performed. Normality of the data and differences between patients and controls were tested by Kolmogorov-Smirnov and t-test, respectively. Correlation with age was studied using Spearman’s rank correlation and an ANCOVA-like analysis. Magnetic susceptibility values were decreased in the red nucleus (p0.95; between -15 and -22 ppb depending on reference region) with a trend toward increasing differences with age. R2* revealed significantly decreased relaxation in the optic radiations of five of the 12 patients (p<0.0001; -3.136±0.567 s-1). Decreased relaxation in the optic radiation is indicative for demyelination, which is in line with previous findings. Decreased magnetic susceptibility in the red nucleus is indicative for a lower brain iron concentration, a chemical redistribution of iron into less magnetic forms, or both. Further investigations are necessary to elucidate the pathological cause or consequence of this finding. PMID:27171423

  18. Cyclohexane, a potential drug of abuse with pernicious effects for the brain

    Directory of Open Access Journals (Sweden)

    Oscar eGonzalez-Perez

    2016-01-01

    Full Text Available Cyclohexane is a volatile solvent used as a harmless substitute for dangerous organic solvents in several products, such as paint thinners, gasoline and adhesives. Many of these products are used as drugs of abuse and can severely damage neural tissue and impair neurological functions. However, there is very little information on the effects of cyclohexane on the brain. In humans, cyclohexane produces headaches, sleepiness, dizziness, limb weakness, motor changes and verbal memory impairment. Recent studies in mice have demonstrated behavioral alterations, reactive gliosis, microglial reactivity and oxidative stress in the brains of cyclohexane-exposed animals. This indicates that cyclohexane may represent a potential problem for public health. Therefore, studies are needed to clarify the neurobiological effects of this volatile compound, including the cellular and molecular mechanisms of neurotoxicity, and to minimize the human health risk posed by the intentional or accidental inhalation of this potential drug of abuse.

  19. Action prediction based on anticipatory brain potentials during simulated driving

    Science.gov (United States)

    Khaliliardali, Zahra; Chavarriaga, Ricardo; Gheorghe, Lucian Andrei; Millán, José del R.

    2015-12-01

    Objective. The ability of an automobile to infer the driver’s upcoming actions directly from neural signals could enrich the interaction of the car with its driver. Intelligent vehicles fitted with an on-board brain-computer interface able to decode the driver’s intentions can use this information to improve the driving experience. In this study we investigate the neural signatures of anticipation of specific actions, namely braking and accelerating. Approach. We investigated anticipatory slow cortical potentials in electroencephalogram recorded from 18 healthy participants in a driving simulator using a variant of the contingent negative variation (CNV) paradigm with Go and No-go conditions: count-down numbers followed by ‘Start’/‘Stop’ cue. We report decoding performance before the action onset using a quadratic discriminant analysis classifier based on temporal features. Main results. (i) Despite the visual and driving related cognitive distractions, we show the presence of anticipatory event related potentials locked to the stimuli onset similar to the widely reported CNV signal (with an average peak value of -8 μV at electrode Cz). (ii) We demonstrate the discrimination between cases requiring to perform an action upon imperative subsequent stimulus (Go condition, e.g. a ‘Red’ traffic light) versus events that do not require such action (No-go condition; e.g. a ‘Yellow’ light); with an average single trial classification performance of 0.83 ± 0.13 for braking and 0.79 ± 0.12 for accelerating (area under the curve). (iii) We show that the centro-medial anticipatory potentials are observed as early as 320 ± 200 ms before the action with a detection rate of 0.77 ± 0.12 in offline analysis. Significance. We show for the first time the feasibility of predicting the driver’s intention through decoding anticipatory related potentials during simulated car driving with high recognition rates.

  20. The Potential of the Human Connectome as a Biomarker of Brain Disease

    Directory of Open Access Journals (Sweden)

    Marcus eKaiser

    2013-08-01

    Full Text Available The human connectome at the level of fiber tracts between brain regions has been shown to differ in patients with brain disorders compared to healthy control groups. Nonetheless, there is a potentially large number of different network organizations for individual patients that could lead to cognitive deficits prohibiting correct diagnosis. Therefore changes that can distinguish groups might not be sufficient to diagnose the disease that an individual patient suffers from and to indicate the best treatment option for that patient. We describe the challenges introduced by the large variability of connectomes within healthy subjects and patients and outline three common strategies to use connectomes as biomarkers of brain diseases. Finally, we propose a fourth option in using models of simulated brain activity (the dynamic connectome based on structural connectivity rather than the structure (connectome itself as a biomarker of disease. Dynamic connectomes, in addition to currently used structural, functional, or effective connectivity, could be an important future biomarker for clinical applications.

  1. Brain potentials index executive functions during random number generation.

    Science.gov (United States)

    Joppich, Gregor; Däuper, Jan; Dengler, Reinhard; Johannes, Sönke; Rodriguez-Fornells, Antoni; Münte, Thomas F

    2004-06-01

    The generation of random sequences is considered to tax different executive functions. To explore the involvement of these functions further, brain potentials were recorded in 16 healthy young adults while either engaging in random number generation (RNG) by pressing the number keys on a computer keyboard in a random sequence or in ordered number generation (ONG) necessitating key presses in the canonical order. Key presses were paced by an external auditory stimulus to yield either fast (1 press/800 ms) or slow (1 press/1300 ms) sequences in separate runs. Attentional demands of random and ordered tasks were assessed by the introduction of a secondary task (key-press to a target tone). The P3 amplitude to the target tone of this secondary task was reduced during RNG, reflecting the greater consumption of attentional resources during RNG. Moreover, RNG led to a left frontal negativity peaking 140 ms after the onset of the pacing stimulus, whenever the subjects produced a true random response. This negativity could be attributed to the left dorsolateral prefrontal cortex and was absent when numbers were repeated. This negativity was interpreted as an index for the inhibition of habitual responses. Finally, in response locked ERPs a negative component was apparent peaking about 50 ms after the key-press that was more prominent during RNG. Source localization suggested a medial frontal source. This effect was tentatively interpreted as a reflection of the greater monitoring demands during random sequence generation. PMID:15140558

  2. Event-related potentials indicate context effect in reading ambiguous words.

    Science.gov (United States)

    Kotchoubey, Boris; El-Khoury, Sylvain

    2014-10-29

    The aim of the study was a comparison of lexical and contextual factors in understanding ambiguous words in German. First, a sample of native speakers selected 56 words having maximally strong differences between a dominant and a subordinate meaning. After this, another sample from the same population was visually presented with sentences that activated dominant or subordinate meanings of the words and were accompanied by probes associated with dominant or subordinate meanings. This resulted in a crossed design with two factors: sentence dominant vs. sentence subordinate and probe dominant vs. probe subordinate. An analysis of event-related brain potentials revealed a large, long-lasting and highly-significant N400 wave whenever the meaning of the probe was incongruent with the meaning of the sentence and the lack of this wave whenever the two meanings were congruent. In the typical N400 space and time, the effect was independent of whether the lexical word meaning was dominant or subordinate. At other sites and times, however (e.g., at lateral frontal electrodes F7/F8, and after 700ms), the congruence effect was significant after dominant sentences only. The data indicate that lexical factors have a rather limited influence on the activation of a particular meaning of ambiguous words. A strong context can virtually override even a very strong difference in the preference for different meanings. PMID:25463139

  3. Anisotropic Anomalous Diffusion assessed in the human brain by scalar invariant indices

    CERN Document Server

    De Santis, S; Bozzali, M; Maraviglia, B; Macaluso, E; Capuani, S

    2010-01-01

    A new method to investigate anomalous diffusion in human brain is proposed. The method has been inspired by both the stretched-exponential model proposed by Hall and Barrick (HB) and DTI. Quantities extracted using HB method were able to discriminate different cerebral tissues on the basis of their complexity, expressed by the stretching exponent gamma and of the anisotropy of gamma across different directions. Nevertheless, these quantities were not defined as scalar invariants like mean diffusivity and fractional anisotropy, which are eigenvalues of the diffusion tensor. We hypotesize instead that the signal may be espressed as a simple stretched-exponential only along the principal axes of diffusion, while in a generic direction the signal is modeled as a combination of three different stretched-exponentials. In this way, we derived indices to quantify both the tissue anomalous diffusion and its anisotropy, independently of the reference frame of the experiment. We tested and compare our new method with DT...

  4. Anticipatory Processing in the Brain on the Perception of Müller-Lyer Illusionary Figures—A Brain Potential Study

    Science.gov (United States)

    Nomura, Shusaku; Sasaki, Shuntaro; Hirakawa, Masato; Hiwaki, Osamu

    2010-11-01

    We investigated the brain potential in relation with the recognition of Müller-Lyer (ML) illusionary figure, which was a famous optical illusion. Although it is frequently assumed that the ML illusionary effect could be derived from its geometrical construction, it derives the same length miss-estimation effect on the sense of touch; haptic illusion. Moreover it occurs in people who are blindfolded or congenital blind. Thus somehow higher information processing than the optical one within the brain could be expected to involve with the recognition of ML figure while few brain studies have demonstrated it. We then investigated the brain waves under subjects' perceiving ML illusionary figure. As a result the marked difference of the brain potential between ML and the control condition around the midline of parietal brain, where the multi-modal perception information was thought to associate within the brain, was observed. This result implies that the anticipatory processing on the perception of ML illusionary figures would be derived by integrating multi-sensory information.

  5. Brain Potentials for Derivational Morphology: An ERP Study of Deadjectival Nominalizations in Spanish

    Science.gov (United States)

    Havas, Viktoria; Rodriguez-Fornells, Antoni; Clahsen, Harald

    2012-01-01

    This study investigates brain potentials to derived word forms in Spanish. Two experiments were performed on derived nominals that differ in terms of their productivity and semantic properties but are otherwise similar, an acceptability judgment task and a reading experiment using event-related brain potentials (ERPs) in which correctly and…

  6. Event-related brain potentials in emotion perception research, individual cognitive assessment and brain-computer interfaces

    OpenAIRE

    Bostanov, Vladimir

    2003-01-01

    All of the experimental and theoretical work presented in this dissertation has been inspired by the general idea of applying event-related brain potential (ERP) measurement and assessment for practical purposes: cognitive diagnostics and Brain-Computer Interfaces (BCI) for paralyzed people. In Chapter 1, two new ERP paradigms are introduced, which were developed for the diagnostics of a particular cognitive function, the recognition of affective prosody. The affective state of a speaker ...

  7. Perspectives and Potential of the Brain-Computer Interface

    Directory of Open Access Journals (Sweden)

    MUSSATTO, G. G.

    2014-06-01

    Full Text Available A Brain-Computer Interface (BCI, also known as Brain-Machine Interface, is a system that allows for the interaction between the user and its surroundings using control signals generated by his brain activity. The improvement of the research on BCI correlates mainly with the advances of Neurophisiology and Computer Science. Initial research was dedicated to the development of devices for the communication of individuals who lost voluntary muscle control but had no cognitive impairment. Nowadays, we find applications in the fields of mobility, communication and the treatment of diseases of user who may or may not have movement impairment. Considering the expansion scenario of the BCI applications, this paper presents a pedagogical description of the recent publication on this field of study. Hence, we descrive the basic concepts related to this research area, as well as some of its applications and limitations.

  8. Epigenetic Modifications, Alcoholic Brain and Potential Drug Targets

    Science.gov (United States)

    Jangra, Ashok; Sriram, Chandra Shaker; Pandey, Suryanarayan; Choubey, Priyansha; Rajput, Prabha; Saroha, Babita; Bezbaruah, Babul Kumar; Lahkar, Mangala

    2016-01-01

    Acute and chronic alcohol exposure evidently influences epigenetic changes, both transiently and permanently, and these changes in turn influence a variety of cells and organ systems throughout the body. Many of the alcohol-induced epigenetic modifications can contribute to cellular adaptations that ultimately lead to behavioral tolerance and alcohol dependence. The persistence of behavioral changes demonstrates that long-lasting changes in gene expression, within particular regions of the brain, may contribute importantly to the addiction phenotype. The research activities over the past years have demonstrated a crucial role of epigenetic mechanisms in causing long lasting and transient changes in the expression of several genes in diverse tissues, including brain. This has stimulated recent research work that is aimed at characterizing the influence of epigenetic regulatory events in mediating the long lasting and transient effects of alcohol abuse on the brain in humans and animal models of alcohol addiction. In this study, we update our current understanding of the impact of alcohol exposure on epigenetic mechanisms in the brain and refurbish the knowledge of epigenetics in the direction of new drugs development. PMID:27780992

  9. Potential application of hydrogen in traumatic and surgical brain injury, stroke and neonatal hypoxia-ischemia

    OpenAIRE

    Eckermann Jan M; Krafft Paul R; Shoemaker Lorelei; Lieberson Robert E; Chang Steven D; Colohan Austin

    2012-01-01

    Abstract This article summarized findings of current preclinical studies that implemented hydrogen administration, either in the gas or liquid form, as treatment application for neurological disorders including traumatic brain injury (TBI), surgically induced brain injury (SBI), stroke, and neonatal hypoxic-ischemic brain insult (HI). Most reviewed studies demonstrated neuroprotective effects of hydrogen administration. Even though anti-oxidative potentials have been reported in several studi...

  10. Deep brain stimulation and ablation for obsessive compulsive disorder: evolution of contemporary indications, targets and techniques.

    Science.gov (United States)

    Tierney, Travis S; Abd-El-Barr, Muhammad M; Stanford, Arielle D; Foote, Kelly D; Okun, Michael S

    2014-06-01

    Surgical therapy for treatment-resistant obsessive compulsive disorder (OCD) remains an effective option for well-selected patients managed within a multidisciplinary setting. Historically, lesions within the limbic system have been used to control both obsessive thoughts and repetitive compulsions associated with this disease. We discuss classical targets as well as contemporary neuromodulatory approaches that have been shown to provide symptomatic relief. Recently, deep brain stimulation (DBS) of the anterior limb of the internal capsule/ventral striatum received Conformité Européene (CE) mark and Food and Drug Administration (FDA) approvals for treatment of intractable OCD. Remarkably, this is the first such approval for neurosurgical intervention in a strictly psychiatric indication in modern times. This target is discussed in detail along with alternative targets currently being proposed. We close with a discussion of gamma knife capsulotomy, a modality with deep historical roots. Further directions in the surgical treatment of OCD will require better preoperative predictors of postoperative responses, optimal selection of individualized targets, and rigorous reporting of adverse events and standardized outcomes. To meet these challenges, centers must be equipped with a multidisciplinary team and patient-centered approach to ensure adequate screening and follow up of patients with this difficult-to-treat condition. PMID:24099662

  11. Integrating Terrain and Vegetation Indices for Identifying Potential Soil Erosion Risk Area

    Institute of Scientific and Technical Information of China (English)

    Arabinda Sharma

    2010-01-01

    The present paper offers an innovative method to monitor the change in soil erosion potential by integrating terrain and vegetation indices derived from remote sensing data. Three terrain indices namely, topographic wetness index (TWI), stream power index (SPI) and slope length factor (LS), were derived from the digital elevation model. Normalized vegetation index (NDVI) was derived for the year 1988 and 2004 using remote sensing images. K-mean clustering was performed on staked indices to categorize the study area into four soil erosion potential classes. The validation of derived erosion potential map using USLE model showed a good agreement. Results indicated that there was a significant change in the erosion potential of the watershed and a gradual shifting of lower erosion potential class to next higher erosion potential class over the study period.

  12. MicroRNAs in Brain Metastases: Potential Role as Diagnostics and Therapeutics

    Directory of Open Access Journals (Sweden)

    Samer Alsidawi

    2014-06-01

    Full Text Available Brain metastases remain a daunting adversary that negatively impact patient survival. Metastatic brain tumors affect up to 45% of all cancer patients with systemic cancer and account for ~20% of all cancer-related deaths. A complex network of non-coding RNA molecules, microRNAs (miRNAs, regulate tumor metastasis. The brain micro-environment modulates metastatic tumor growth; however, defining the precise genetic events that promote metastasis in the brain niche represents an important, unresolved problem. Understanding these events will reveal disease-based targets and offer effective strategies to treat brain metastases. Effective therapeutic strategies based upon the biology of brain metastases represent an urgent, unmet need with immediate potential for clinical impact. Studies have demonstrated the ability of miRNAs to distinguish normal from cancerous cells, primary from secondary brain tumors, and correctly categorize metastatic brain tumor tissue of origin based solely on miRNA profiles. Interestingly, manipulation of miRNAs has proven effective in cancer treatment. With the promise of reduced toxicity, increased efficacy and individually directed personalized anti-cancer therapy, using miRNA in the treatment of metastatic brain tumors may prove very useful and improve patient outcome. In this review, we focus on the potential of miRNAs as diagnostic and therapeutic targets for the treatment of metastatic brain lesions.

  13. Broad-Band Visually Evoked Potentials: Re(convolution in Brain-Computer Interfacing.

    Directory of Open Access Journals (Sweden)

    Jordy Thielen

    Full Text Available Brain-Computer Interfaces (BCIs allow users to control devices and communicate by using brain activity only. BCIs based on broad-band visual stimulation can outperform BCIs using other stimulation paradigms. Visual stimulation with pseudo-random bit-sequences evokes specific Broad-Band Visually Evoked Potentials (BBVEPs that can be reliably used in BCI for high-speed communication in speller applications. In this study, we report a novel paradigm for a BBVEP-based BCI that utilizes a generative framework to predict responses to broad-band stimulation sequences. In this study we designed a BBVEP-based BCI using modulated Gold codes to mark cells in a visual speller BCI. We defined a linear generative model that decomposes full responses into overlapping single-flash responses. These single-flash responses are used to predict responses to novel stimulation sequences, which in turn serve as templates for classification. The linear generative model explains on average 50% and up to 66% of the variance of responses to both seen and unseen sequences. In an online experiment, 12 participants tested a 6 × 6 matrix speller BCI. On average, an online accuracy of 86% was reached with trial lengths of 3.21 seconds. This corresponds to an Information Transfer Rate of 48 bits per minute (approximately 9 symbols per minute. This study indicates the potential to model and predict responses to broad-band stimulation. These predicted responses are proven to be well-suited as templates for a BBVEP-based BCI, thereby enabling communication and control by brain activity only.

  14. The relationship between serum brain-derived neurotrophic factor (BDNF) and cardiometabolic indices in schizophrenia.

    Science.gov (United States)

    Nurjono, Milawaty; Tay, Yi Hang; Lee, Jimmy

    2014-08-01

    Brain derived neurotrophic factor (BDNF), which has been implicated in the pathogenesis of schizophrenia, has been recently shown to be involved in the regulation of metabolism and energy homeostasis. This study seeks to examine the relationship between BDNF, metabolic indices and cardiovascular (CVD) risk in patients with schizophrenia. Medical histories, demographic information and anthropometric measurements were collected and analyzed from 61 participants with schizophrenia. Fasting glucose and lipids were measured in a central laboratory, and serum BDNF was analyzed using commercially available enzyme-linked immunosorbent assay (ELISA). The 10-year CVD risk for each participant was computed using the Framingham risk score (FRS). Linear regressions were performed to examine the relationships between serum BDNF with body mass index (BMI), blood pressure (BP), triglycerides (TG), total cholesterol, high-density lipoprotein cholesterol (HDL-C) and glucose. To examine the relationship between serum BDNF and FRS, serum BDNF was categorized into quartiles, and a multiple regression was performed. After adjusting for age, gender and current smoking status, diastolic BP (dBP) (p=0.045) and TG (p=0.015) were found to be significantly associated with serum BDNF. Participants in the highest quartile of serum BDNF had a 3.3 times increase in FRS over those in the lowest quartile. Our findings support the possible regulatory role of BDNF in metabolism and cardiovascular homeostasis among patients with schizophrenia similar to that observed among the non-mentally ill. Serum BDNF not only present itself as a candidate biomarker of schizophrenia but also might be a viable marker of metabolic co-morbidities associated with schizophrenia.

  15. NeuroGrid: recording action potentials from the surface of the brain

    OpenAIRE

    Khodagholy, Dion; Gelinas, Jennifer N.; Thesen, Thomas; Doyle, Werner; Devinsky, Orrin; Malliaras, George G.; Buzsáki, György

    2014-01-01

    Recording from neural networks at the resolution of action potentials is critical for understanding how information is processed in the brain. Here, we address this challenge by developing an organic material-based, ultra-conformable, biocompatible and scalable neural interface array (the ‘NeuroGrid’) that can record both LFP and action potentials from superficial cortical neurons without penetrating the brain surface. Spikes with features of interneurons and pyramidal cells were simultaneous...

  16. Potential predictors for the amount of intra-operative brain shift during deep brain stimulation surgery

    Science.gov (United States)

    Datteri, Ryan; Pallavaram, Srivatsan; Konrad, Peter E.; Neimat, Joseph S.; D'Haese, Pierre-François; Dawant, Benoit M.

    2011-03-01

    A number of groups have reported on the occurrence of intra-operative brain shift during deep brain stimulation (DBS) surgery. This has a number of implications for the procedure including an increased chance of intra-cranial bleeding and complications due to the need for more exploratory electrodes to account for the brain shift. It has been reported that the amount of pneumocephalus or air invasion into the cranial cavity due to the opening of the dura correlates with intraoperative brain shift. Therefore, pre-operatively predicting the amount of pneumocephalus expected during surgery is of interest toward accounting for brain shift. In this study, we used 64 DBS patients who received bilateral electrode implantations and had a post-operative CT scan acquired immediately after surgery (CT-PI). For each patient, the volumes of the pneumocephalus, left ventricle, right ventricle, third ventricle, white matter, grey matter, and cerebral spinal fluid were calculated. The pneumocephalus was calculated from the CT-PI utilizing a region growing technique that was initialized with an atlas-based image registration method. A multi-atlas-based image segmentation method was used to segment out the ventricles of each patient. The Statistical Parametric Mapping (SPM) software package was utilized to calculate the volumes of the cerebral spinal fluid (CSF), white matter and grey matter. The volume of individual structures had a moderate correlation with pneumocephalus. Utilizing a multi-linear regression between the volume of the pneumocephalus and the statistically relevant individual structures a Pearson's coefficient of r = 0.4123 (p = 0.0103) was found. This study shows preliminary results that could be used to develop a method to predict the amount of pneumocephalus ahead of the surgery.

  17. Processing of global and local properties——An analysis with event-related brain potentials

    Institute of Scientific and Technical Information of China (English)

    韩世辉; 陈霖

    1996-01-01

    The different processing of global and local properties of compound visual stimuli was studied with event-related brain potentials (ERPs) in the present experiment. It was found that, compared with the identification of global properties, the discrimination of local properties elicited longer RTs, lower accuracies, increased amplitudes of P1, decreased amplitudes of N1, and longer latencies of N2 and P3. The conflict of global and local properties increased the amplitudes of P2, decreased the amplitudes of P3, and prolonged latencies of N2 and P3. These results indicated that the advantage of global processing occurs at an early perceptual stage, and the attentional mechanisms for global and local processing may be different.

  18. 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 ...

  19. Simulation of 2D Brain's Potential Distribution Based on Two Electrodes ECVT Using Finite Element Method

    Science.gov (United States)

    Sirait, S. H.; Edison, R. E.; Baidillah, M. R.; Taruno, W. P.; Haryanto, F.

    2016-08-01

    The aim of this study is to simulate the potential distribution of 2D brain geometry based on two electrodes ECVT. ECVT (electrical capacitance tomography) is a tomography modality which produces dielectric distribution image of a subject from several capacitance electrodes measurements. This study begins by producing the geometry of 2D brain based on MRI image and then setting the boundary conditions on the boundaries of the geometry. The values of boundary conditions follow the potential values used in two electrodes brain ECVT, and for this reason the first boundary is set to 20 volt and 2.5 MHz signal and another boundary is set to ground. Poisson equation is implemented as the governing equation in the 2D brain geometry and finite element method is used to solve the equation. Simulated Hodgkin-Huxley action potential is applied as disturbance potential in the geometry. We divide this study into two which comprises simulation without disturbance potential and simulation with disturbance potential. From this study, each of time dependent potential distributions from non-disturbance and disturbance potential of the 2D brain geometry has been generated.

  20. Parafoveal X-masks interfere with foveal word recognition: Evidence from fixation-related brain potentials.

    Directory of Open Access Journals (Sweden)

    Florian eHutzler

    2013-07-01

    Full Text Available AbstractThe boundary paradigm, in combination with parafoveal masks, is the main technique for studying parafoveal preprocessing during reading. The rationale is that the masks (e.g., strings of X’s prevent parafoveal preprocessing, but do not interfere with foveal processing. A recent study, however, raised doubts about the neutrality of parafoveal masks. In the present study, we explored this issue by means of fixation-related brain potentials (FRPs. Two FRP conditions presented rows of 5 words. The task of the participant was to judge whether the final word of a list was a new word, or whether it was a repeated (i.e., old word. The critical manipulation was that the final word was X-masked during parafoveal preview in one condition, whereas another condition presented a valid preview of the word. In two additional event-related brain potential (ERP conditions, the words were presented serially with no parafoveal preview available; in one of the conditions with a fixed timing, in the other word presentation was self-paced by the participants. Expectedly, the valid-preview FRP condition elicited the shortest processing times. Processing times did not differ between the two ERP conditions indicating that cognitive readiness during self-paced processing can be ruled out as an alternative explanation for differences in processing times between the ERP and the FRP conditions. The longest processing times were found in the X-mask FRP condition indicating that parafoveal X-masks interfere with foveal word recognition.

  1. From event-related potential to oscillations: genetic diathesis in brain (dys)function and alcohol dependence.

    Science.gov (United States)

    Rangaswamy, Madhavi; Porjesz, Bernice

    2008-01-01

    Recording the brain's electrical activity using electrodes placed on the individual's scalp provides noninvasive sensitive measures of brain function in humans. Regardless of whether an individual receives sensory information or performs higher cognitive processes, the brain regions involved exhibit measurable electrical activity, and by recording this activity with numerous electrodes placed on different areas of the scalp, researchers can determine when and where in the brain information processing occurs. Two general approaches can be used to record these neuroelectric phenomena: The continuous electroencephalogram (EEG) records brain activity when the subject is at rest and not involved in a task. It reflects the sum of the random activity of thousands of neurons that have similar spatial orientation in the brain. This activity typically fluctuates in wave-like patterns, and depending on the frequency of these patterns, one distinguishes different brain waves called δ (frequency of 1 to 3 Hz), θ (frequency of 4 to 7 Hz), α (frequency of 8 to 12 Hz), β (frequency of 12 to 28 Hz), and γ (frequency of 28+ Hz) rhythms. Variations in the patterns of these brain waves can indicate the level of consciousness, psychological state, or presence of neurological disorders. Event-related potentials (ERPs) are recorded while the subject is performing a sensory or cognitive task. They reflect the summated activity of network ensembles active during the task and are characterized by a specific pattern called the waveform, which is composed of negative and positive deflections (i.e., waves). For example, a target stimulus detected amidst a series of other nontarget stimuli produces a positive wave around 300 milliseconds after the stimulus. This is known as the P300 or P3 response.

  2. Identifying the null subject: evidence from event-related brain potentials.

    Science.gov (United States)

    Demestre, J; Meltzer, S; García-Albea, J E; Vigil, A

    1999-05-01

    Event-related brain potentials (ERPs) were recorded during spoken language comprehension to study the on-line effects of gender agreement violations in controlled infinitival complements. Spanish sentences were constructed in which the complement clause contained a predicate adjective marked for syntactic gender. By manipulating the gender of the antecedent (i.e., the controller) of the implicit subject while holding constant the gender of the adjective, pairs of grammatical and ungrammatical sentences were created. The detection of such a gender agreement violation would indicate that the parser had established the coreference relation between the null subject and its antecedent. The results showed a complex biphasic ERP (i.e., an early negativity with prominence at anterior and central sites, followed by a centroparietal positivity) in the violating condition as compared to the non-violating conditions. The brain reacts to NP-adjective gender agreement violations within a few hundred milliseconds of their occurrence. The data imply that the parser has properly coindexed the null subject of an infinitive clause with its antecedent. PMID:10344021

  3. 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.

  4. In Vivo Functional Brain Imaging Approach Based on Bioluminescent Calcium Indicator GFP-aequorin.

    Science.gov (United States)

    Lark, Arianna R; Kitamoto, Toshihiro; Martin, Jean-René

    2016-01-08

    Functional in vivo imaging has become a powerful approach to study the function and physiology of brain cells and structures of interest. Recently a new method of Ca(2+)-imaging using the bioluminescent reporter GFP-aequorin (GA) has been developed. This new technique relies on the fusion of the GFP and aequorin genes, producing a molecule capable of binding calcium and - with the addition of its cofactor coelenterazine - emitting bright light that can be monitored through a photon collector. Transgenic lines carrying the GFP-aequorin gene have been generated for both mice and Drosophila. In Drosophila, the GFP-aequorin gene has been placed under the control of the GAL4/UAS binary expression system allowing for targeted expression and imaging within the brain. This method has subsequently been shown to be capable of detecting both inward Ca(2+)-transients and Ca(2+)-released from inner stores. Most importantly it allows for a greater duration in continuous recording, imaging at greater depths within the brain, and recording at high temporal resolutions (up to 8.3 msec). Here we present the basic method for using bioluminescent imaging to record and analyze Ca(2+)-activity within the mushroom bodies, a structure central to learning and memory in the fly brain.

  5. Development of a new biomechanical indicator for primary blast-induced brain injury

    Institute of Scientific and Technical Information of China (English)

    Feng Zhu; Cliff C.Chou; King H.Yang; Albert I.King

    2015-01-01

    Primary blast-induced traumatic brain injury (bTBI) has been observed at the boundary of brain tissue and cerebrospinal fluid (CSF).Such injury can hardly be explained by using the theory of compressive wave propagation,since both the solid and fluid materials have similar compressibility and thus the intracranial pressure (ICP) has a continuous distribution across the boundary.Since they have completely different shear properties,it is hypothesized the injury at the interface is caused by shear wave.In the present study,a preliminary combined numerical and theoretical analysis was conducted based on the theory of shear wave propagation]reflection.Simulation results show that higher lateral acceleration of brain tissue particles is concentrated in the boundary region.Based on this finding,a new biomechanical vector,termed as strain gradient,was suggested for primary bTBI.The subsequent simple theoretical analysis reveals that this parameter is proportional to the value of lateral acceleration.At the boundary of lateral ventricles,high spatial strain gradient implies that the brain tissue in this area (where neuron cells may be contained) undergo significantly different strains and large velocity discontinuity,which may result in mechanical damage of the neuron cells.

  6. Guanosine: a Neuromodulator with Therapeutic Potential in Brain Disorders

    Science.gov (United States)

    Lanznaster, Débora; Dal-Cim, Tharine; Piermartiri, Tetsadê C. B.; Tasca, Carla I.

    2016-01-01

    Guanosine is a purine nucleoside with important functions in cell metabolism and a protective role in response to degenerative diseases or injury. The past decade has seen major advances in identifying the modulatory role of extracellular action of guanosine in the central nervous system (CNS). Evidence from rodent and cell models show a number of neurotrophic and neuroprotective effects of guanosine preventing deleterious consequences of seizures, spinal cord injury, pain, mood disorders and aging-related diseases, such as ischemia, Parkinson’s and Alzheimer’s diseases. The present review describes the findings of in vivo and in vitro studies and offers an update of guanosine effects in the CNS. We address the protein targets for guanosine action and its interaction with glutamatergic and adenosinergic systems and with calcium-activated potassium channels. We also discuss the intracellular mechanisms modulated by guanosine preventing oxidative damage, mitochondrial dysfunction, inflammatory burden and modulation of glutamate transport. New and exciting avenues for future investigation into the protective effects of guanosine include characterization of a selective guanosine receptor. A better understanding of the neuromodulatory action of guanosine will allow the development of therapeutic approach to brain diseases. PMID:27699087

  7. Thyroid hormone’s role in regulating brain glucose metabolism and potentially modulating hippocampal cognitive processes

    OpenAIRE

    Jahagirdar, V; McNay, EC

    2012-01-01

    Cognitive performance is dependent on adequate glucose supply to the brain. Insulin, which regulates systemic glucose metabolism, has been recently shown both to regulate hippocampal metabolism and to be a mandatory component of hippocampally-mediated cognitive performance. Thyroid hormones (TH) regulate systemic glucose metabolism and may also be involved in regulation of brain glucose metabolism. Here we review potential mechanisms for such regulation. Importantly, TH imbalance is often enc...

  8. Steady state visually evoked potentials based Brain computer interface test outside the lab

    OpenAIRE

    Eduardo Francisco Caicedo Bravo; Jaiber Evelio Cardona Aristizábal

    2016-01-01

    Context: Steady State Visually Evoked Potentials (SSVEP) are brain signals which are one of the most promising signals for Brain Computer Interfaces (BCIs) implementation, however, SSVEP based BCI generally are proven in a controlled environment and there are a few tests in demanding conditions.Method: We present a SSVEP based BCI system that was used outside the lab in a noisy environment with distractions, and with the presence of public. For the tests, we showed a maze in a laptop where th...

  9. A step into the anarchist’s mind: examining political attitudes and ideology through event-related brain potentials

    Science.gov (United States)

    Van Hiel, Alain; Pattyn, Sven; Onraet, Emma; Severens, Els

    2012-01-01

    The present study investigates patterns of event-related brain potentials following the presentation of attitudinal stimuli among political moderates (N = 12) and anarchists (N = 11). We used a modified oddball paradigm to investigate the evaluative inconsistency effect elicited by stimuli embedded in a sequence of contextual stimuli with an opposite valence. Increased late positive potentials (LPPs) of extreme political attitudes were observed. Moreover, this LPP enhancement was larger among anarchists than among moderates, indicating that an extreme political attitude of a moderate differs from an extreme political attitude of an anarchist. The discussion elaborates on the meaning of attitude extremity for moderates and extremists. PMID:21421734

  10. Donepezil markedly potentiates memantine neurotoxicity in the adult rat brain

    OpenAIRE

    Creeley, Catherine E.; Wozniak, David F.; Nardi, Anthony; Farber, Nuri B.; Olney, John W.

    2006-01-01

    The NMDA antagonist, memantine (Namenda), and the cholinesterase inhibitor, donepezil (Aricept), are currently being used widely, either individually or in combination, for treatment of Alzheimer’s disease (AD). NMDA antagonists have both neuroprotective and neurotoxic properties; the latter is augmented by drugs, such as pilocarpine, that increase cholinergic activity. Whether donepezil, by increasing cholinergic activity, might augment memantine’s neurotoxic potential has not been investiga...

  11. Performance enhancement at the cost of potential brain plasticity: neural ramifications of nootropic drugs in the healthy developing brain

    Science.gov (United States)

    Urban, Kimberly R.; Gao, Wen-Jun

    2014-01-01

    Cognitive enhancement is perhaps one of the most intriguing and controversial topics in neuroscience today. Currently, the main classes of drugs used as potential cognitive enhancers include psychostimulants (methylphenidate (MPH), amphetamine), but wakefulness-promoting agents (modafinil) and glutamate activators (ampakine) are also frequently used. Pharmacologically, substances that enhance the components of the memory/learning circuits—dopamine, glutamate (neuronal excitation), and/or norepinephrine—stand to improve brain function in healthy individuals beyond their baseline functioning. In particular, non-medical use of prescription stimulants such as MPH and illicit use of psychostimulants for cognitive enhancement have seen a recent rise among teens and young adults in schools and college campuses. However, this enhancement likely comes with a neuronal, as well as ethical, cost. Altering glutamate function via the use of psychostimulants may impair behavioral flexibility, leading to the development and/or potentiation of addictive behaviors. Furthermore, dopamine and norepinephrine do not display linear effects; instead, their modulation of cognitive and neuronal function maps on an inverted-U curve. Healthy individuals run the risk of pushing themselves beyond optimal levels into hyperdopaminergic and hypernoradrenergic states, thus vitiating the very behaviors they are striving to improve. Finally, recent studies have begun to highlight potential damaging effects of stimulant exposure in healthy juveniles. This review explains how the main classes of cognitive enhancing drugs affect the learning and memory circuits, and highlights the potential risks and concerns in healthy individuals, particularly juveniles and adolescents. We emphasize the performance enhancement at the potential cost of brain plasticity that is associated with the neural ramifications of nootropic drugs in the healthy developing brain. PMID:24860437

  12. Performance enhancement at the cost of potential brain plasticity: neural ramifications of nootropic drugs in the healthy developing brain.

    Science.gov (United States)

    Urban, Kimberly R; Gao, Wen-Jun

    2014-01-01

    Cognitive enhancement is perhaps one of the most intriguing and controversial topics in neuroscience today. Currently, the main classes of drugs used as potential cognitive enhancers include psychostimulants (methylphenidate (MPH), amphetamine), but wakefulness-promoting agents (modafinil) and glutamate activators (ampakine) are also frequently used. Pharmacologically, substances that enhance the components of the memory/learning circuits-dopamine, glutamate (neuronal excitation), and/or norepinephrine-stand to improve brain function in healthy individuals beyond their baseline functioning. In particular, non-medical use of prescription stimulants such as MPH and illicit use of psychostimulants for cognitive enhancement have seen a recent rise among teens and young adults in schools and college campuses. However, this enhancement likely comes with a neuronal, as well as ethical, cost. Altering glutamate function via the use of psychostimulants may impair behavioral flexibility, leading to the development and/or potentiation of addictive behaviors. Furthermore, dopamine and norepinephrine do not display linear effects; instead, their modulation of cognitive and neuronal function maps on an inverted-U curve. Healthy individuals run the risk of pushing themselves beyond optimal levels into hyperdopaminergic and hypernoradrenergic states, thus vitiating the very behaviors they are striving to improve. Finally, recent studies have begun to highlight potential damaging effects of stimulant exposure in healthy juveniles. This review explains how the main classes of cognitive enhancing drugs affect the learning and memory circuits, and highlights the potential risks and concerns in healthy individuals, particularly juveniles and adolescents. We emphasize the performance enhancement at the potential cost of brain plasticity that is associated with the neural ramifications of nootropic drugs in the healthy developing brain. PMID:24860437

  13. Performance Enhancement at the Cost of Potential Brain Plasticity: Neural Ramifications of Nootropic Drugs in the Healthy Developing Brain

    Directory of Open Access Journals (Sweden)

    Kimberly R. Urban

    2014-05-01

    Full Text Available Cognitive enhancement is perhaps one of the most intriguing and controversial topics in neuroscience today. Currently, the main classes of drugs used as potential cognitive enhancers include psychostimulants (methylphenidate, amphetamine, but wakefulness-promoting agents (modafinil and glutamate activators (ampakine are also frequently used. Pharmacologically, substances that enhance the components of the memory/learning circuits - dopamine, glutamate (neuronal excitation, and/or norepinephrine - stand to improve brain function in healthy individuals beyond their baseline functioning. In particular, non-medical use of prescription stimulants such as methylphenidate and illicit use of psychostimulants for cognitive enhancement have seen a recent rise among teens and young adults in schools and college campuses. However, this enhancement likely comes with a neuronal, as well as ethical, cost. Altering glutamate function via the use of psychostimulants may impair behavioral flexibility, leading to the development and/or potentiation of addictive behaviors. Furthermore, dopamine and norepinephrine do not display linear effects; instead, their modulation of cognitive and neuronal function maps on an inverted-U curve. Healthy individuals run the risk of pushing themselves beyond optimal levels into hyperdopaminergic and hypernoradrenergic states, thus vitiating the very behaviors they are striving to improve. Finally, recent studies have begun to highlight potential damaging effects of stimulant exposure in healthy juveniles. This review explains how the main classes of cognitive enhancing drugs affect the learning and memory circuits, and highlights the potential risks and concerns in healthy individuals, particularly juveniles and adolescents. We emphasize the performance enhancement at the potential cost of brain plasticity that is associated with the neural ramifications of nootropic drugs in the healthy developing brain.

  14. Hyperdensity of the Basilar Artery on Postmortem CT: A Potential Indicator for Basilar Artery Thrombosis.

    Science.gov (United States)

    Garland, Jack; Tse, Rexson; Beh, Raymond J; Lyons, Timothy J; Cala, Allan D

    2016-06-01

    Basilar artery thrombosis constitutes 1% of all types of stroke, carries a mortality rate of up to 90%, and is one of the rarer causes of sudden death. It leads to brain stem ischemia and commonly presents with impaired consciousness, cranial nerve palsy, hemiplegia or quadriplegia, and sudden collapse. Clinically, the diagnosis of basilar artery thrombosis is made on clinical symptoms, along with a hyperdense basilar artery in antemortem computed tomography (CT) scan. To our knowledge, whether a hyperdense basilar artery indicates basilar artery thrombosis on postmortem CT scan is not documented in the literature. We present a case report of a 55-year-old man who on postmortem CT scan showed a hyperdense basilar artery and was subsequently confirmed to be a fatal basilar artery thrombosis. We suggest that a hyperdense basilar artery on postmortem CT should prompt the pathologist to consider basilar artery thrombosis. PMID:27049662

  15. [Determination of irreversibility of clinical brain death. Electroencephalography and evoked potentials].

    Science.gov (United States)

    Buchner, H; Ferbert, A

    2016-02-01

    Principally, in the fourth update of the rules for the procedure to finally determine the irreversible cessation of function of the cerebrum, the cerebellum and the brainstem, the importance of an electroencephalogram (EEG), somatosensory evoked potentials (SEP) and brainstem auditory evoked potentials (BAEP) are confirmed. This paper presents the reliability and validity of the electrophysiological diagnosis, discusses the amendments in the fourth version of the guidelines and introduces the practical application, problems and sources of error.An EEG is the best established supplementary diagnostic method for determining the irreversibility of clinical brain death syndrome. It should be noted that residual brain activity can often persist for many hours after the onset of brain death syndrome, particularly in patients with primary brainstem lesions. The derivation and analysis of an EEG requires a high level of expertise to be able to safely distinguish artefacts from primary brain activity. The registration of EEGs to demonstrate the irreversibility of clinical brain death syndrome is extremely time consuming.The BAEPs can only be used to confirm the irreversibility of brain death syndrome in serial examinations or in the rare cases of a sustained wave I or sustained waves I and II. Very often, an investigation cannot be reliably performed because of existing sound conduction disturbances or failure of all potentials even before the onset of clinical brain death syndrome. This explains why BAEPs are only used in exceptional cases.The SEPs of the median nerve can be very reliably derived, are technically simple and with few sources of error. A serial investigation is not required and the time needed for examination is short. For these reasons SEPs are given preference over EEGs and BAEPs for establishing the irreversibility of clinical brain death syndrome. PMID:26785843

  16. BRAIN DYSFUNCTION OF PATIENTS WITH QIGONG INDUCED MENTAL DISORDER REVEALED BY EVOKED POTENTIALS RECORDING

    Institute of Scientific and Technical Information of China (English)

    LU Yingzhi; ZONG Wenbin; CHEN Xingshi

    2003-01-01

    Objective: In order to investigate the brain function of patients with Qigong induced mental disorder (QIMD), this study was carried out. Methods: Four kinds of evoked potentials, including contingent negative variation (CNV), auditory evoked potentials (AEP), visual evoked potentials (VEP), and somatosensory evoked potentials (SEP), were recorded from 12 patients with Qigong induced mental disorder.Comparison of their evoked potentials with the data from some normal controls was made. Results: The results revealed that there were 3 kinds of abnormal changes in evoked potentials of patients with QIMD that is latency prolongation, amplitude increase and amplitude decrease, as compared with normal controls. Conclusion: Brain dysfunction of patients with QIMD was confirmed. Its biological mechanism needs further studying.

  17. Scientific Research in the Kingdom of Saudi Arabia: Potential for Excellence and Indicators of Underdevelopment

    Science.gov (United States)

    Alshayea, Ali

    2013-01-01

    This study analyzes the status of scientific research and development efforts in the Kingdom of Saudi Arabia, and then sheds lights on the potential for excellence in this area in terms of organization and structure, financing and partnership, and human resources. Accordingly, the study reviews both achievements and indicators of underdevelopment…

  18. EDUCATIONAL POTENTIAL OF DEVELOPMENT: INTERNATIONAL COMPARISONS ON THE BASIS OF STATISTICAL INDICATORS

    Directory of Open Access Journals (Sweden)

    S. Bychkova

    2014-04-01

    Full Text Available Using information WEF, UNDP, OECD investigated differences in the characteristics of education as a factor of competitiveness and level of development of countries, formed the group of OECD countries and their partners, significantly differ in indicators of education, studied Russian position among OECD countries and BRICS, formulated conclusions about ways of improving the educational potential of the country

  19. Brain potentials implicate temporal lobe abnormalities in criminal psychopaths.

    Science.gov (United States)

    Kiehl, Kent A; Bates, Alan T; Laurens, Kristin R; Hare, Robert D; Liddle, Peter F

    2006-08-01

    Psychopathy is associated with abnormalities in attention and orienting. However, few studies have examined the neural systems underlying these processes. To address this issue, the authors recorded event-related potentials (ERPs) while 80 incarcerated men, classified as psychopathic or nonpsychopathic via the Hare Psychopathy Checklist--Revised (R. D. Hare, 1991, 2003), completed an auditory oddball task. Consistent with hypotheses, processing of targets elicited larger frontocentral negativities (N550) in psychopaths than in nonpsychopaths. Psychopaths also showed an enlarged N2 and reduced P3 during target detection. Similar ERP modulations have been reported in patients with amygdala and temporal lobe damage. The data are interpreted as supporting the hypothesis that psychopathy may be related to dysfunction of the paralimbic system--a system that includes parts of the temporal and frontal lobes. PMID:16866585

  20. MT-Stabilizer, Dictyostatin, Exhibits Prolonged Brain Retention and Activity: Potential Therapeutic Implications

    Science.gov (United States)

    2013-01-01

    Inclusions comprising the microtubule (MT)-stabilizing protein, tau, are found within neurons in the brains of patients with Alzheimer’s disease and related neurodegenerative disorders that are broadly referred to as tauopathies. The sequestration of tau into inclusions is believed to cause a loss of tau function, such that MT structure and function are compromised, leading to neuronal damage. Recent data reveal that the brain-penetrant MT-stabilizing agent, epothilone D (EpoD), improves cognitive function and decreases both neuron loss and tau pathology in transgenic mouse models of tauopathy. There is thus a need to identify additional MT-stabilizing compounds with blood–brain barrier (BBB) permeability and slow brain clearance, as observed with EpoD. We report here that the MT-stabilizing natural product, dictyostatin, crosses the BBB in mice and has extended brain retention. Moreover, a single administration of dictyostatin to mice causes prolonged stabilization of MTs in the brain. In contrast, the structurally related MT-stabilizer, discodermolide, shows significantly less brain exposure. Thus, dictyostatin merits further investigation as a potential tauopathy therapeutic. PMID:24900764

  1. MT-Stabilizer, Dictyostatin, Exhibits Prolonged Brain Retention and Activity: Potential Therapeutic Implications.

    Science.gov (United States)

    Brunden, Kurt R; Gardner, Nicola M; James, Michael J; Yao, Yuemang; Trojanowski, John Q; Lee, Virginia M-Y; Paterson, Ian; Ballatore, Carlo; Smith, Amos B

    2013-09-12

    Inclusions comprising the microtubule (MT)-stabilizing protein, tau, are found within neurons in the brains of patients with Alzheimer's disease and related neurodegenerative disorders that are broadly referred to as tauopathies. The sequestration of tau into inclusions is believed to cause a loss of tau function, such that MT structure and function are compromised, leading to neuronal damage. Recent data reveal that the brain-penetrant MT-stabilizing agent, epothilone D (EpoD), improves cognitive function and decreases both neuron loss and tau pathology in transgenic mouse models of tauopathy. There is thus a need to identify additional MT-stabilizing compounds with blood-brain barrier (BBB) permeability and slow brain clearance, as observed with EpoD. We report here that the MT-stabilizing natural product, dictyostatin, crosses the BBB in mice and has extended brain retention. Moreover, a single administration of dictyostatin to mice causes prolonged stabilization of MTs in the brain. In contrast, the structurally related MT-stabilizer, discodermolide, shows significantly less brain exposure. Thus, dictyostatin merits further investigation as a potential tauopathy therapeutic.

  2. Combining stereotactic radiosurgery and systemic therapy for brain metastases: a potential role for temozolomide

    Directory of Open Access Journals (Sweden)

    Matthew E Hardee

    2012-08-01

    Full Text Available Brain metastases are unfortunately very common in the natural history of many solid tumors and remain a life-threatening condition, associated with a dismal prognosis, despite many clinical trials aimed at improving outcomes. Radiation therapy options for brain metastases include whole brain radiotherapy (WBRT and stereotactic radiosurgery (SRS. SRS avoids the potential toxicities of WBRT and is associated with excellent local control rates. However, distant intracranial failure following SRS remains a problem, suggesting that untreated intracranial micrometastatic disease is responsible for failure of treatment. The oral alkylating agent temozolomide (TMZ, which has demonstrated efficacy in primary malignant central nervous system tumors such as glioblastoma, has been used in early phase trials in the treatment of established brain metastases. Although results of these studies in established, macroscopic metastatic disease have been modest at best, there is clinical and preclinical data to suggest that TMZ is more efficacious at treating and controlling clinically undetectable intracranial micrometastatic disease. We review the available data for the primary management of brain metastases with SRS, as well as the use of TMZ in treating established brain metastases and undetectable micrometastatic disease, and suggest the role for a clinical trial with the aims of treating macroscopically visible brain metastases with SRS combined with TMZ to address microscopic, undetectable disease.

  3. The potential for bio-mediators and biomarkers in pediatric traumatic brain injury and neurocritical care

    Directory of Open Access Journals (Sweden)

    Patrick M. Kochanek

    2013-04-01

    Full Text Available The use of biomarkers of brain injury in pediatric neurocritical care has been explored for at least 15 years. Two general lines of research on biomarkers in pediatric brain injury have been pursued, 1 studies of bio-mediators in cerebrospinal fluid (CSF of children after traumatic brain injury (TBI to explore the components of the secondary injury cascades in an attempt to identify potential therapeutic targets and 2 studies of the release of structural proteins into the CSF, serum, or urine in order to diagnose, monitor, and/or prognosticate in patients with TBI or other pediatric neurocritical care conditions. Unique age-related differences in brain biology, disease processes, and clinical applications mandate the development and testing of brain injury bio-mediators and biomarkers specifically in pediatric neurocritical care applications. Finally, although much of the early work on biomarkers of brain injury in pediatrics has focused on TBI, new applications are emerging across a wide range of applications specifically for pediatric neurocritical care including abusive head trauma, cardiopulmonary arrest, septic shock, extracorporeal membrane oxygenation, hydrocephalus, and cardiopulmonary bypass. The potential scope of the utility of biomarkers in pediatric neurocritical care is thus also discussed.

  4. Brain potentials associated with the shape Stroop effect.

    Science.gov (United States)

    Xiao, Xiao; Xie, Peng; Zhang, Qinglin

    2016-03-23

    Event-related potentials (ERPs) were recorded to explore, for the first time, the electrophysiological correlates of the shape Stroop effect. Fifteen healthy individuals were presented with a frame and a name of an object with a typical shape in life and asked to categorize the object's typical shape in life as a 'circle', a 'square,' or a 'triangle' by pressing the relevant button as quickly as possible. Accurate categorization of the name of an object was faster when it was presented with a congruent shape frame (e.g. name of a tyre/circle frame) than with an incongruent one (e.g. name of a tyre/square frame). Scalp ERPs analysis showed that the incongruent condition elicited a more negative component N430 and a more late positive component LPC than the congruent condition. N430 is a critical sign of conflict detection in the early stage, whereas late positive component reflects the response conflict in the late stage. The results provided evidence for the dissociation between conflict detection and conflict resolution in the shape Stroop effect. PMID:26862935

  5. Establishing and testing the "reuse potential" indicator for managing wastes as resources.

    Science.gov (United States)

    Park, Joo Young; Chertow, Marian R

    2014-05-01

    This study advances contemporary ideas promoting the importance of managing wastes as resources such as closed-loop or circular material economies, and sustainable materials management by reinforcing the notion of a resource-based paradigm rather than a waste-based one. It features the creation of a quantitative tool, the "reuse potential indicator" to specify how "resource-like" versus how "waste-like" specific materials are on a continuum. Even with increasing attention to waste reuse and resource conservation, constant changes in product composition and complexity have left material managers without adequate guidance to make decisions about what is technically feasible to recover from the discard stream even before markets can be considered. The reuse potential indicator is developed to aid management decision-making about waste based not on perception but more objectively on the technical ability of the materials to be reused in commerce. This new indicator is based on the extent of technological innovation and commercial application of actual reuse approaches identified and cataloged. Coal combustion by-products (CCBs) provide the test case for calculating the reuse potential indicator. While CCBs are often perceived as wastes and then isolated in landfills or surface impoundments, there is also a century-long history in the industry of developing technologies to reuse CCBs. The recent statistics show that most CCBs generated in Europe and Japan are reused (90-95%), but only 40-45% of CCBs are used in the United States. According to the reuse potential calculation, however, CCBs in the United States have high technical reusability. Of the four CCBs examined under three different regulatory schemes, reuse potential for boiler slag and flue-gas desulfurization gypsum maintains a value greater than 0.8 on a 0-1 scale, indicating they are at least 80% resource-like. Under current regulation in the United States, both fly ash and bottom ash are 80-90% resource

  6. The Estimate of Territorial Development Potential using Criterions and Specific Economic Indicators. Case Study Galati County

    Directory of Open Access Journals (Sweden)

    Daniela Ancuta SARPE

    2012-11-01

    Full Text Available This paper has proposed to study potential peripheral areas of the Municipality of Galati, Galati County to set up a metropolitan area that is a vector of development for towns and villages in the area. Have been identified as priority areas for assessing the potential of the area, the economic one, society, habitat and administrative capacity, which are the areas on which one can obtain EU funds for development projects. Economics was evaluated on the basis of nine specific indicators, using specific information from villages in the Galati County. Based on the level of indicators examined, it has been analyzed the possibility of including in the metropolitan area the villages located at a distance of utmost 30 km. In this way we could make an estimate of the delimitation of a developed area adjacent to Galati City, also identifying new directions to expand this area to Braila Municipality.

  7. Neuroprotective potential of molecular hydrogen against perinatal brain injury via suppression of activated microglia.

    Science.gov (United States)

    Imai, Kenji; Kotani, Tomomi; Tsuda, Hiroyuki; Mano, Yukio; Nakano, Tomoko; Ushida, Takafumi; Li, Hua; Miki, Rika; Sumigama, Seiji; Iwase, Akira; Hirakawa, Akihiro; Ohno, Kinji; Toyokuni, Shinya; Takeuchi, Hideyuki; Mizuno, Tetsuya; Suzumura, Akio; Kikkawa, Fumitaka

    2016-02-01

    Exposure to inflammation in utero is related to perinatal brain injury, which is itself associated with high rates of long-term morbidity and mortality in children. Novel therapeutic interventions during the perinatal period are required to prevent inflammation, but its pathogenesis is incompletely understood. Activated microglia are known to play a central role in brain injury by producing a variety of pro-inflammatory cytokines and releasing oxidative products. The study is aimed to investigate the preventative potential of molecular hydrogen (H2), which is an antioxidant and anti-inflammatory agent without mutagenicity. Pregnant ICR mice were injected with lipopolysaccharide (LPS) intraperitoneally on embryonic day 17 to create a model of perinatal brain injury caused by prenatal inflammation. In this model, the effect of maternal administration of hydrogen water (HW) on pups was also evaluated. The levels of pro-inflammatory cytokines, oxidative damage and activation of microglia were determined in the fetal brains. H2 reduced the LPS-induced expression of pro-inflammatory cytokines, oxidative damage and microglial activation in the fetal brains. Next, we investigated how H2 contributes to neuroprotection, focusing on microglia, using primary cultured microglia and neurons. H2 prevented LPS- or cytokine-induced generation of reactive oxidative species by microglia and reduced LPS-induced microglial neurotoxicity. Finally, we identified several molecules influenced by H2, involved in the process of activating microglia. These results suggested that H2 holds promise for the prevention of inflammation related to perinatal brain injury. PMID:26709014

  8. Blockage of transient receptor potential vanilloid 4 inhibits brain edema in middle cerebral artery occlusion mice

    Directory of Open Access Journals (Sweden)

    Pinghui eJie

    2015-04-01

    Full Text Available Brain edema is an important pathological process during stroke. Activation of transient receptor potential vanilloid 4 (TRPV4 causes an up-regulation of matrix metalloproteinases (MMPs in lung tissue. MMP can digest the endothelial basal lamina to destroy blood brain barrier, leading to vasogenic brain edema. Herein, we tested whether TRPV4-blockage could inhibit brain edema through inhibiting MMPs in middle cerebral artery occlusion (MCAO mice. We found that the brain water content and Evans blue extravasation at 48 h post-MCAO were reduced by a TRPV4 antagonist HC-067047. The increased MMP-2/9 protein in hippocampus of MCAO mice was attenuated by HC-067046, but only the increased MMP-9 activity was blocked by HC-067047. The loss of zonula occluden-1 (ZO-1 and occludin protein in MCAO mice was also attenuated by HC-067047. Moreover, MMP-2/9 protein increased in mice treated with a TRPV4 agonist GSK1016790A, but only MMP-9 activity was increased by GSK1016790A. Finally, ZO-1 and occludin protein was decreased by GSK1016790A, which was reversed by an MMP-9 inhibitor. We conclude that blockage of TRPV4 may inhibit brain edema in cerebral ischemia through inhibiting MMP-9 activation and the loss of tight junction protein.

  9. Two Languages, One Developing Brain: Event-Related Potentials to Words in Bilingual Toddlers

    Science.gov (United States)

    Conboy, Barbara T.; Mills, Debra L.

    2006-01-01

    Infant bilingualism offers a unique opportunity to study the relative effects of language experience and maturation on brain development, with each child serving as his or her own control. Event-related potentials (ERPs) to words were examined in 19- to 22-month-old English-Spanish bilingual toddlers. The children's dominant vs. nondominant…

  10. Event-related brain potentials reflect discourse-referential ambiguity in spoken language comprehension.

    NARCIS (Netherlands)

    J.J.A. van Berkum; C.M. Brown; P. Hagoort; P. Zwitserlood

    2003-01-01

    In two experiments, we explored the use of event-related brain potentials to selectively track the processes that establish reference during spoken language comprehension. Subjects listened to stories in which a particular noun phrase like "the girl" either uniquely referred to a single referent men

  11. Mental Rotation of Mirrored Letters: Evidence from Event-Related Brain Potentials

    Science.gov (United States)

    Nunez-Pena, M. Isabel; Aznar-Casanova, J. Antonio

    2009-01-01

    Event-related brain potentials (ERPs) were recorded while participants (n=13) were presented with mirrored and normal letters at different orientations and were asked to make mirror-normal letter discriminations. As it has been suggested that a mental rotation out of the plane might be necessary to decide on mirrored letters, we wanted to…

  12. Scalp topography of event-related brain potentials and cognitive transitions during childhood.

    NARCIS (Netherlands)

    P.C.M. Molenaar; M.W. van der Molen; J.E.A. Stauder

    1993-01-01

    Examined the relation between cognitive development (CGD) and the ontogenesis of event-related brain potentials (ERPs) during childhood among 48 girls (aged 5-7 yrs). The level of CGD was assessed with a standard Piagetian conservation kit. Ss performed a visual selective attention (oddball) task an

  13. Atypical Brain Responses to Reward Cues in Autism as Revealed by Event-Related Potentials

    Science.gov (United States)

    Kohls, Gregor; Peltzer, Judith; Schulte-Ruther, Martin; Kamp-Becker, Inge; Remschmidt, Helmut; Herpertz-Dahlmann, Beate; Konrad, Kerstin

    2011-01-01

    Social motivation deficit theories suggest that children with autism do not properly anticipate and appreciate the pleasure of social stimuli. In this study, we investigated event-related brain potentials evoked by cues that triggered social versus monetary reward anticipation in children with autism. Children with autism showed attenuated P3…

  14. Decision making on organ donation: the dilemmas of relatives of potential brain dead donors

    NARCIS (Netherlands)

    Groot, J.J.A.M. de; Hoek, M.; Hoedemaekers, C.W.E.; Hoitsma, A.J.; Smeets, W.; Vernooij-Dassen, M.J.F.J.; Leeuwen, E. van

    2015-01-01

    BACKGROUND: This article is part of a study to gain insight into the decision-making process by looking at the views of the relatives of potential brain dead donors. Alongside a literature review, focus interviews were held with healthcare professionals about their role in the request and decision-m

  15. Potential of optical microangiography to monitor cerebral blood perfusion and vascular plasticity following traumatic brain injury in mice in vivo

    Science.gov (United States)

    Jia, Yali; Alkayed, Nabil; Wang, Ruikang K.

    2009-07-01

    Optical microanglography (OMAG) is a recently developed imaging modality capable of volumetric imaging of dynamic blood perfusion, down to capillary level resolution, with an imaging depth up to 2.00 mm beneath the tissue surface. We report the use of OMAG to monitor the cerebral blood flow (CBF) over the cortex of mouse brain upon traumatic brain injury (TBI), with the cranium left intact, for a period of two weeks on the same animal. We show the ability of OMAG to repeatedly image 3-D cerebral vasculatures during pre- and post-traumatic phases, and to visualize the changes of regulated CBF and the vascular plasticity after TBI. The results indicate the potential of OMAG to explore the mechanism involved in the rehabilitation of TBI.

  16. Ecosystem Service Potentials, Flows and Demands – Concepts for Spatial Localisation, Indication and Quantification

    Directory of Open Access Journals (Sweden)

    Benjamin Burkhard

    2014-06-01

    Full Text Available The high variety of ecosystem service categorisation systems, assessment frameworks, indicators, quantification methods and spatial localisation approaches allows scientists and decision makers to harness experience, data, methods and tools. On the other hand, this variety of concepts and disagreements among scientists hamper an integration of ecosystem services into contemporary environmental management and decision making. In this article, the current state of the art of ecosystem service science regarding spatial localisation, indication and quantification of multiple ecosystem service supply and demand is reviewed and discussed. Concepts and tables for regulating, provisioning and cultural ecosystem service definitions, distinguishing between ecosystem service potential supply (stocks, flows (real supply and demands as well as related indicators for quantification are provided. Furthermore, spatial concepts of service providing units, benefitting areas, spatial relations, rivalry, spatial and temporal scales are elaborated. Finally, matrices linking CORINE land cover types to ecosystem service potentials, flows, demands and budget estimates are provided. The matrices show that ecosystem service potentials of landscapes differ from flows, especially for provisioning ecosystem services.

  17. Emotion and the processing of symbolic gestures: an event-related brain potential study

    OpenAIRE

    Flaisch, Tobias; Häcker, Frank; Renner, Britta; Schupp, Harald

    2010-01-01

    The present study used event-related brain potentials to examine the hypothesis that emotional gestures draw attentional resources at the level of distinct processing stages. Twenty healthy volunteers viewed pictures of hand gestures with negative (insult) and positive (approval) emotional meaning as well as neutral control gestures (pointing) while dense sensor event-related potentials (ERPs) were recorded. Emotion effects were reflected in distinct ERP modulations in early and later time wi...

  18. Surplus Cost Potential as a Life Cycle Impact Indicator for Metal Extraction

    Directory of Open Access Journals (Sweden)

    Marisa D.M. Vieira

    2016-01-01

    Full Text Available In the evaluation of product life cycles, methods to assess the increase in scarcity of resources are still under development. Indicators that can express the importance of an increase in scarcity of metals extracted include surplus ore produced, surplus energy required, and surplus costs in the mining and the milling stage. Particularly the quantification of surplus costs per unit of metal extracted as an indicator is still in an early stage of development. Here, we developed a method that quantifies the surplus cost potential of mining and milling activities per unit of metal extracted, fully accounting for mine-specific differences in costs. The surplus cost potential indicator is calculated as the average cost increase resulting from all future metal extractions, as quantified via cumulative cost-tonnage relationships. We tested the calculation procedure with 12 metals and platinum-group metals as a separate group. We found that the surplus costs range six orders of magnitude between the metals included, i.e., between $0.01–$0.02 (iron and $13,533–$17,098 (rhodium USD (year 2013 per kilogram of metal extracted. The choice of the reserve estimate (reserves vs. ultimate recoverable resource influenced the surplus costs only to a limited extent, i.e., between a factor of 0.7 and 3.2 for the metals included. Our results provide a good basis to regularly include surplus cost estimates as resource scarcity indicator in life cycle assessment.

  19. Ionic profile of honey as a potential indicator of botanical origin and global environmental pollution

    International Nuclear Information System (INIS)

    Aim of this study was to determine by Ion Chromatography ions (Na+, Ca++, Mg++, NH4+, Cl−, Br−, SO42−, NO3−, PO43−) in honeys (honeydew and floral nectar honeys) from different Italian Regions and from countries of the Western Balkan area. The compositional data were processed by multivariate analysis (PCA and HCA). Arboreal honeydew honeys from the Western Balkans had higher concentrations (from two to three times) of some environmental pollutants (Br−, SO42− and PO43− contents), due to industrial and agricultural activities, than those from Italian regions. The cationic profiles were very similar in both groups. Multivariate analysis indicated a clear difference between nectar honeys and arboreal/honeydew honeys (recognition of the botanical origin). These findings point to the potential of ionic constituents of honey as indicators of environmental pollution, botanical origin and authenticity. -- Highlights: •Analysis by IC of honeys from two areas with different environmental pollution (Italy and Balkans). •Chemometric techniques such as PCA and HCA used. •In Balkans area higher Br−, SO42− and PO43− due to industrial and agricultural activities. •Discrimination of honey botanical origin and authenticity on the base of IC data. •Honey ionic profiles as indicators of environmental pollution and botanical origin. -- Capsule: Ionic profiles of honey could be potential indicators of environmental pollution (industrial and agricultural), botanical origin and authenticity

  20. Prognostic value of evoked and event-related potentials in moderate to severe brain injury.

    Science.gov (United States)

    Lew, Henry L; Poole, John H; Castaneda, Annabel; Salerno, Rose Marie; Gray, Max

    2006-01-01

    Clinicians are often expected to project patients' clinical outcomes to allow effective planning for future care. This can be a challenge in patients with moderate to severe traumatic brain injury (TBI) who are often unable to participate reliably in clinical evaluations. With recent advances in computer instrumentation and signal processing, evoked potentials and event-related potentials show increasing promise as powerful tools for prognosticating the trajectory of recovery and ultimate outcome from the TBI. Short- and middle-latency evoked potentials can now effectively predict coma outcomes in patients with acute TBI. Long-latency event-related potential components hold promise in predicting recovery of higher order cognitive abilities. PMID:16915010

  1. A prospective comparative clinical study of peripheral blood counts and indices in patients with primary brain tumors

    Science.gov (United States)

    Subeikshanan, V; Dutt, A; Basu, D; Tejus, MN; Maurya, VP; Madhugiri, VS

    2016-01-01

    Background: Elevation of the neutrophil to lymphocyte ratio (NLR) has been shown to be an indicator of poor prognosis in many malignancies including recurrent glioblastoma multiforme. Objectives: This study was aimed at assessing if the NLR and other leukocyte counts and indices were deranged in treatment-naïve patients with primary brain tumors when compared with an age-matched healthy control group. Materials and Methods: This was a prospective comparative clinical observational study by design. A healthy control population was compared with treatment-naïve patients diagnosed with intra- and extraaxial brain tumors. Leukocyte counts (neutrophil, lymphocyte, monocyte, eosinophil, and basophil counts) as well as leukocyte ratios such as the NLR and the monocyte to lymphocyte ratio (MLR) were calculated. We also evaluated if the counts and indices were related to the tumor volume. Results: In all patients with tumors, the platelet and neutrophil counts were elevated when compared to the controls. In contrast, monocyte counts and the MLR were found to be decreased in patients with tumors when compared to the controls. The subset of patients with glioblastoma showed a significant increase in NLR when compared to the controls. Conclusions: Significant changes in the neutrophil, monocyte, and platelet counts as well as NLR and MLR were observed. Prospective longitudinal studies are required to determine the prognostic and therapeutic implications of these findings. PMID:27089106

  2. Electrophysiological Indices of Brain Activity to Content and Function Words in Discourse

    Science.gov (United States)

    Neumann, Yael; Epstein, Baila; Shafer, Valerie L.

    2016-01-01

    Background: An increase in positivity of event-related potentials (ERPs) at the lateral anterior sites has been hypothesized to be an index of semantic and discourse processing, with the right lateral anterior positivity (LAP) showing particular sensitivity to discourse factors. However, the research investigating the LAP is limited; it is unclear…

  3. Human enteric viruses–potential indicators for enhanced monitoring of recreational water quality

    Institute of Scientific and Technical Information of China (English)

    Erin; Allmann; Updyke; Zi; Wang; Si; Sun; Christina; Connell; Marek; Kirs; Mayee; Wong; Yuanan; Lu

    2015-01-01

    Recreational waters contaminated with human fecal pollution are a public health concern, and ensuring the safety of recreational waters for public use is a priority of both the Environmental Protection Agency(EPA) and the Centers for Disease Control and Prevention(CDC). Current recreational water standards rely on fecal indicator bacteria(FIB) levels as indicators of human disease risk. However present evidence indicates that levels of FIB do not always correspond to the presence of other potentially harmful organisms, such as viruses. Thus, enteric viruses are currently tested as water quality indicators, but have yet to be successfully implemented in routine monitoring of water quality. This study utilized enteric viruses as possible alternative indicators of water quality to examine 18 different fresh and offshore recreational waters on O‘ahu, Hawai‘i, by using newly established laboratory techniques including highly optimized PCR, real time PCR, and viral infectivity assays. All sample sites were detected positive for human enteric viruses by PCR including enterovirus, norovirus genogroups I and II, and male specific FRNA coliphage. A six time-point seasonal study of enteric virus presence indicated significant variation in virus detection between the rainy and dry seasons. Quantitative PCR detected the presence of norovirus genogroup II at levels at which disease risk may occur, and there was no correlation found between enteric virus presence and FIB counts. Under the present laboratory conditions, no infectious viruses were detected from the samples PCR-positive for enteric viruses. These data emphasize both the need for additional indicators for improved monitoring of water quality, and the feasibility of using enteric viruses as these indicators.

  4. A comment on Farwell : brain fingerprinting: a comprehensive tutorial review of detection of concealed information with event-related brain potentials

    NARCIS (Netherlands)

    E.H. Meijer; G. Ben-Shakhar; B. Verschuere; E. Donchin

    2013-01-01

    In a recent issue of Cognitive Neurodynamics Farwell (Cogn Neurodyn 6:115-154, 2012) published a comprehensive tutorial review of the use of Event Related Brain Potentials (ERP) in the detection of concealed information. Farwell’s review covered much of his own work employing his ‘‘brain fingerprint

  5. Effect of Acupuncture on the Auditory Evoked Brain Stem Potential in Parkinson's Disease

    Institute of Scientific and Technical Information of China (English)

    王玲玲; 何崇; 刘跃光; 朱莉莉

    2002-01-01

    @@ Under the auditory evoked brain stem potential (ABP) examination, the latent period of V wave and the intermittent periods of III-V peak and I-V peak were significantly shortened in Parkinson's disease patients of the treatment group (N=29) after acupuncture treatment. The difference of cumulative scores in Webster's scale was also decreased in correlation analysis. The increase of dopamine in the brain and the excitability of the dopamine neurons may contribute to the therapeutic effects, in TCM terms, of subduing the pathogenic wind and tranquilizing the mind.

  6. Clinically Relevant Pharmacological Strategies That Reverse MDMA-Induced Brain Hyperthermia Potentiated by Social Interaction.

    Science.gov (United States)

    Kiyatkin, Eugene A; Ren, Suelynn; Wakabayashi, Ken T; Baumann, Michael H; Shaham, Yavin

    2016-01-01

    MDMA-induced hyperthermia is highly variable, unpredictable, and greatly potentiated by the social and environmental conditions of recreational drug use. Current strategies to treat pathological MDMA-induced hyperthermia in humans are palliative and marginally effective, and there are no specific pharmacological treatments to counteract this potentially life-threatening condition. Here, we tested the efficacy of mixed adrenoceptor blockers carvedilol and labetalol, and the atypical antipsychotic clozapine, in reversing MDMA-induced brain and body hyperthermia. We injected rats with a moderate non-toxic dose of MDMA (9 mg/kg) during social interaction, and we administered potential treatment drugs after the development of robust hyperthermia (>2.5 °C), thus mimicking the clinical situation of acute MDMA intoxication. Brain temperature was our primary focus, but we also simultaneously recorded temperatures from the deep temporal muscle and skin, allowing us to determine the basic physiological mechanisms of the treatment drug action. Carvedilol was modestly effective in attenuating MDMA-induced hyperthermia by moderately inhibiting skin vasoconstriction, and labetalol was ineffective. In contrast, clozapine induced a marked and immediate reversal of MDMA-induced hyperthermia via inhibition of brain metabolic activation and blockade of skin vasoconstriction. Our findings suggest that clozapine, and related centrally acting drugs, might be highly effective for reversing MDMA-induced brain and body hyperthermia in emergency clinical situations, with possible life-saving results. PMID:26105141

  7. Developing a composite indicator to measure civic participatory potential in two Chinese societies

    Directory of Open Access Journals (Sweden)

    Lijuan Li

    2016-12-01

    Full Text Available This study examined whether there is evidence in Hong Kong and Taiwan students’ early attitudes to civic participation that suggests they will adopt radical forms of civic participation and whether civic participatory potential of students from these two Chinese societies differed in early adolescence. To achieve these purposes, we used a Rasch measurement approach to construct comparable profiles. In doing so, we adopted conceptual and empirical approaches to construct a composite indicator and then tested validity and reliability of this indicator for the two societies, respectively. Such an approach is based on the assumption that reliable and accurate measurement is essential for theorizing the results of empirical studies. The data from the 2009 International Civics and Citizenship Education Study were also used for comparing the potential participation profiles. The results suggested that the unidimensional profile has good item fit and model fit for both societies, thereby valid and reliable. Preliminary findings suggest that inclination towards radical action can be identified during early adolescence and students from the two Chinese societies differed in civic participatory potential. Taiwanese students appear to be more radical than Hong Kong students while maintaining less positive attitudes to conventional forms of citizenship engagement.

  8. 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.

  9. Vocal parameters that indicate threat level correlate with FOS immunolabeling in social and vocal control brain regions.

    Science.gov (United States)

    Ellis, Jesse M S; Riters, Lauren V

    2012-01-01

    Transmitting information via communicative signals is integral to interacting with conspecifics, and some species achieve this task by varying vocalizations to reflect context. Although signal variation is critical to social interactions, the underlying neural control has not been studied. In response to a predator, black-capped chickadees (Poecile atricapilla) produce mobbing calls (chick-a-dee calls) with various parameters, some of which convey information about the threat stimulus. We predicted that vocal parameters indicative of threat would be associated with distinct patterns of neuronal activity within brain areas involved in social behavior and those involved in the sensorimotor control of vocal production. To test this prediction, we measured the syntax and structural aspects of chick-a-dee call production in response to a hawk model and assessed the protein product of the immediate early gene FOS in brain regions implicated in context-specific vocal and social behavior. These regions include the medial preoptic area (POM) and lateral septum (LS), as well as regions involved in vocal motor control, including the dorsomedial nucleus of the intercollicular complex and the HVC. We found correlations linking call rate (previously demonstrated to reflect threat) to labeling in the POM and LS. Labeling in the HVC correlated with the number of D notes per call, which may also signal threat level. Labeling in the call control region dorsomedial nucleus was associated with the structure of D notes and the overall number of notes, but not call rate or type of notes produced. These results suggest that the POM and LS may influence attributes of vocalizations produced in response to predators and that the brain region implicated in song control, the HVC, also influences call production. Because variation in chick-a-dee call rate indicates predator threat, we speculate that these areas could integrate with motor control regions to imbue mobbing signals with additional

  10. Pharmacoscintigraphic evaluation of potential of lipid nanocarriers for nose-to-brain delivery of antidepressant drug.

    Science.gov (United States)

    Alam, M Intakhab; Baboota, Sanjula; Ahuja, Alka; Ali, Mushir; Ali, Javed; Sahni, Jasjeet K; Bhatnagar, Aseem

    2014-08-15

    Efficacy of antidepressants relies upon their continued presence at the site of action (brain) over a prolonged period of time. The BBB restricts the access of antidepressants to the brain on oral as well as intravenous administration. Direct delivery (by-passing the BBB) of antidepressant drugs can increase the CSF concentration with concomitant reduction in dose and side effects. Intranasal administration of nanostructured lipid carriers (NLC) containing antidepressant drug circumvent the BBB and maintain the prolonged release at the site of action. The aim of the present study was to evaluate the enhancement in brain uptake of NLC containing duloxetine (DLX) after intranasal administration. Duloxetine loaded NLC (DLX-NLC) was evaluated pharmacoscintigraphically for drug targeting potential (DTP), drug targeting efficiency (DTE) and biodistribution studies in different organs including brain. The radiolabeling efficiency of DLX and DLX-NLC was found to be 98.41 ± 0.96 and 98.87 ± 0.82 after 30 min, respectively. The biodistribution studies exhibited higher percentage of radioactivity/g for DLX-NLC formulations in brain as compared with the DLX. The higher DTP (86.80%) and DTE (757.74%) suggested that DLX-NLC formulation has a better brain targeting efficiency than DLX solution (DTP=65.12%; DTE=287.34%) when administered intranasally. Moreover, the intranasal administration exhibited about 8-times higher concentration of DLX in brain when compared with the intravenous administration of DLX solution. The intranasal NLC containing DLX can be employed as an effective method for the treatment of depression.

  11. LINKING MOTOR-RELATED BRAIN POTENTIALS AND VELOCITY PROFILES IN MULTI-JOINT ARM REACHING MOVEMENTS

    Directory of Open Access Journals (Sweden)

    Julià L Amengual

    2014-04-01

    Full Text Available The study of the movement related brain potentials (MRPBs needs accurate technical approaches to disentangle the specific patterns of bran activity during the preparation and execution of movements. During the last forty years, synchronizing the electromiographic activation (EMG of the muscle with the electrophysiological recordings (EEG has been commonly ussed for these purposes. However, new clinical approaches in the study of motor diseases and rehabilitation suggest the demand of new paradigms that might go further into the study of the brain activity associated with the kinematics of movement. As a response to this call, we have used a 3-D hand tracking system with the aim to record continuously the position of an ultrasonic sender located on the hand during the performance of multi-joint self-pace movements. We synchronized the time-series of position of velocity of the sender with the EEG recordings, obtaining specific patterns of brain activity as a function of the fluctuations of the kinematics during the natural movement performance. Additionally, the distribution of the brain activity during the preparation and execution phases of movement was similar that reported previously using the EMG, suggesting the validity of our technique. We claim that this paradigm could be usable in patients because of its simplicity and the potential knowledge that can be extracted from clinical protocols.

  12. Local indicators of climate change: The potential contribution of local knowledge to climate research

    Science.gov (United States)

    Reyes-García, Victoria; Fernández-Llamazares, Álvaro; Guèze, Maximilien; Garcés, Ariadna; Mallo, Miguel; Vila-Gómez, Margarita; Vilaseca, Marina

    2016-01-01

    Local knowledge has been proposed as a place-based tool to ground-truth climate models and to narrow their geographic sensitivity. To assess the potential role of local knowledge in our quest to understand better climate change and its impacts, we first need to critically review the strengths and weaknesses of local knowledge of climate change and the potential complementarity with scientific knowledge. With this aim, we conducted a systematic, quantitative meta-analysis of published peer-reviewed documents reporting local indicators of climate change (including both local observations of climate change and observed impacts on the biophysical and the social systems). Overall, primary data on the topic are not abundant, the methodological development is incipient, and the geographical extent is unbalanced. On the 98 case studies documented, we recorded the mention of 746 local indicators of climate change, mostly corresponding to local observations of climate change (40%), but also to observed impacts on the physical (23%), the biological (19%), and the socioeconomic (18%) systems. Our results suggest that, even if local observations of climate change are the most frequently reported type of change, the rich and fine-grained knowledge in relation to impacts on biophysical systems could provide more original contributions to our understanding of climate change at local scale.

  13. Early event-related potentials indicate context-specific target processing for eye and hand motor systems.

    Science.gov (United States)

    Wehrspaun, Claudia C; Pfabigan, Daniela M; Sailer, Uta

    2013-01-01

    Concurrent eye and hand movements toward a common visual target require different motor programs based on identical visual input. We used event-related brain potentials (ERP) to determine if and when the processing of the visual target differs for the two motor systems. The N2, an index for target evaluation, was more negative for the target of a hand than of an eye movement in two experiments. A possible interpretation for this finding is different visual target processing. Targets for hand movements require a different weighting of visual information, for example concerning features such as surface structure which are important for hand but not for eye movements. In experiment 2, the early C1-component, which had an average maximum at 67 ms following target onset, was significantly more negative when subjects pointed at the stimuli. Traditionally, the C1 has been regarded as a sensory component, but recent studies have linked it to higher order processing, such as attention and expectations. Thus, the present data indicate that target processing for eye or hand movements is already context-specific during early visual information processing. We suggest that differences in a target's relevance for upcoming movements modify target processing as well as sensory expectations.

  14. Voxel-based analysis of diffusion tensor indices in the brain in patients with Parkinson's disease

    International Nuclear Information System (INIS)

    Purpose: To investigate the abnormal diffusion in cerebral white matter and its relationship with the olfactory dysfunction in patients with Parkinson's disease (PD) through diffusion tensor imaging (DTI). Materials and methods: Diffusion tensor imaging of the cerebrum was performed in 25 patients with Parkinson's disease and 25 control subjects matched for age and sex. Differences in fractional anisotropy (FA) and mean diffusivity (MD) between these two groups were studied by voxel-based analysis of the DTI data. Correlations between diffusion indices and the olfactory function in PD patients were evaluated using the multiple regression model after controlling for the duration of the disease, Unified Parkinson's Disease Rating Sale (UPDRS), and age. Results: The damaged white and gray matter showed decreased FA or increased MD, localized bilaterally in the cerebellar and orbitofrontal cortex. In addition, in PD patients there was a positive correlation between FA values in the white matter of the left cerebellum and the thresholds of olfactory identification (TOI) and a negative correlation between MD values in the white matter of right cerebellum and the TOI. Conclusion: In patients with PD, there was disruption in the cerebellar white matter which may play an important role in the olfactory dysfunction in patients with Parkinson's disease.

  15. The potential for cell-based therapy in perinatal brain injuries.

    Science.gov (United States)

    Phillips, Andre W; Johnston, Michael V; Fatemi, Ali

    2013-04-01

    Perinatal brain injuries are a leading cause of cerebral palsy worldwide. The potential of stem cell therapy to prevent or reduce these impairments has been widely discussed within the medical and scientific communities and an increasing amount of research is being conducted in this field. Animal studies support the idea that a number of stem cells types, including cord blood and mesenchymal stem cells have a neuroprotective effect in neonatal hypoxia-ischemia. Both these cell types are readily available in a clinical setting. The mechanisms of action appear to be diverse, including immunomodulation, activation of endogenous stem cells, release of growth factors, and anti-apoptotic effects. Here, we review the different types of stem cells and progenitor cells that are potential candidates for therapeutic strategies in perinatal brain injuries, and summarize recent preclinical and clinical studies.

  16. Indices of brain beta-adrenergic receptor signal transduction in the learned helplessness animal model of depression.

    Science.gov (United States)

    Gurguis, G N; Kramer, G; Petty, F

    1996-01-01

    Both stress response and antidepressant drug action may be mediated by beta-adrenergic receptors (beta AR). Since learned helplessness is a stress-induced animal model of depression, beta AR are relevant to investigate in this model. To date, studies have measured changes in total receptor density (RT), but have not examined more detailed aspects of signal transduction mechanisms such as coupling of the receptor to GS protein. We have investigated brain beta AR coupling in the frontal cortex, hippocampus and hypothalamus of rats exposed to inescapable shock and then tested for learned helplessness, and in both tested and naive controls using [125I]-iodocyanopindolol (ICYP) as the ligand. Both antagonist-saturation and agonist-displacement experiments were conducted, and the specificity for the beta AR was optimized by excluding ICYP binding to 5HT1B receptors. The percentage receptor density in the high-conformational state (%RH) and the ratio of agonist (isoproterenol) dissociation constant from the receptor in the low-/high-conformational states (KL/KH) were used as indices of coupling to GS protein. No significant differences were found between rats developing learned helplessness and non-helpless rats after inescapable stress in any parameter measured in any brain region. In the frontal cortex, exposure to inescapable shock induced beta AR uncoupling from GS protein as suggested by a low KL/KH ratio both in helpless and non-helpless rats but not in either control group. In the hypothalamus, there were trends for higher RL, RT and KL/KH ratio in helpless rats and stressed controls compared to naive controls. These findings suggest that beta AR binding parameters in frontal cortex, hippocampus or hypothalamus did not differentiate between helpless and non-helpless rats. Changes in beta AR coupling observed in these brain regions may reflect effects of stress, which appeared to be region-specific, rather than stress-induced behavioral depression.

  17. THE POTENTIAL FOR CELL-BASED THERAPY IN PERINATAL BRAIN INJURIES

    OpenAIRE

    Phillips, Andre W.; Johnston, Michael V.; Fatemi, Ali

    2013-01-01

    Perinatal brain injuries are a leading cause of cerebral palsy worldwide. The potential of stem cell therapy to prevent or reduce these impairments has been widely discussed within the medical and scientific communities and an increasing amount of research is being conducted in this field. Animal studies support the idea that a number of stem cells types, including cord blood and mesenchymal stem cells have a neuroprotective effect in neonatal hypoxia-ischemia. Both these cell types are readi...

  18. Meditation (Vipassana) and the P3a Event-Related Brain Potential

    OpenAIRE

    Cahn, B. Rael; Polich, John

    2008-01-01

    A three-stimulus auditory oddball series was presented to experienced Vipassana meditators during meditation and a control thought period to elicit event-related brain potentials (ERPs) in the two different mental states. The stimuli consisted of a frequent standard tone (500 Hz), an infrequent oddball tone (1000 Hz), and an infrequent distracter (white noise), with all stimuli passively presented through headphones and no task imposed. The strongest meditation compared to control state effec...

  19. Enhancement of the amplitude of somatosensory evoked potentials following magnetic pulse stimulation of the human brain.

    Science.gov (United States)

    Seyal, M; Browne, J K; Masuoka, L K; Gabor, A J

    1993-01-01

    In this study we have demonstrated an enhancement of cortically generated wave forms of the somatosensory evoked potential (SEP) following magnetic pulse stimulation of the human brain. Subcortically generated activity was unaltered. The enhancement of SEP amplitude was greatest when the median nerve was stimulated 30-70 msec following magnetic pulse stimulation over the contralateral parietal scalp. We posit that the enhancement of the SEP is the result of synchronization of pyramidal cells in the sensorimotor cortex resulting from the magnetic pulse.

  20. Brain potentials evoked by intraepidermal electrical stimuli reflect the central sensitization of nociceptive pathways

    OpenAIRE

    Liang, M.; Lee, M. C.; O'Neill, J.; Dickenson, A.H.; Iannetti, G.D.

    2016-01-01

    Central sensitization (CS), the increased sensitivity of the central nervous system to somatosensory inputs, accounts for secondary hyperalgesia, a typical sign of several painful clinical conditions. Brain potentials elicited by mechanical punctate stimulation using flat-tip probes can provide neural correlates of CS, but their signal-to-noise ratio is limited by poor synchronisation of the afferent nociceptive input. Additionally, mechanical punctate stimulation does not activate nociceptor...

  1. An Event-related Brain Potential Study of English Morphosyntactic Processing in Japanese Learners of English

    OpenAIRE

    Tatsuta, Natsuko

    2014-01-01

    This dissertation investigated the neural mechanisms underlying English morphosyntactic processing in Case, subject-verb agreement, and past tense inflection in Japanese learners of English (JLEs) using event-related brain potentials (ERPs) in terms of the effects of the age of second language (L2) acquisition (the age of learning English), L2 proficiency level (the English proficiency level), and native/first language (L1) transfer. Researchers have debated for a number of years the question...

  2. An event-related brain potential study of schizotypal personality and associative semantic processing

    OpenAIRE

    Kiang, Michael; Prugh, Jocelyn; Kutas, Marta

    2009-01-01

    To examine whether schizotypal personality is associated with the degree to which concepts activate each other in semantic memory, event-related brain potentials (ERPs) were recorded during a delayed lexical decision task from healthy volunteers rated for schizotypy. Each target word was directly, indirectly, or not at all related to a prime word preceding it at a 300- or 750-ms stimulus-onset asynchrony (SOA). Overall, N400 amplitudes were largest for unrelated targets, smallest for directly...

  3. Metagenomic analysis indicates Epsilonproteobacteria as a potential cause of microbial corrosion in pipelines injected with bisulfite

    Directory of Open Access Journals (Sweden)

    Dongshan eAn

    2016-01-01

    Full Text Available Sodium bisulfite (SBS is used as an oxygen scavenger to decrease corrosion in pipelines transporting brackish subsurface water used in the production of bitumen by steam-assisted gravity drainage. Sequencing 16S rRNA gene amplicons has indicated that SBS addition increased the fraction of the sulfate-reducing bacteria (SRB Desulfomicrobium, as well as of Desulfocapsa, which can also grow by disproportionating sulfite into sulfide, sulfur and sulfate. SRB use cathodic H2, formed by reduction of aqueous protons at the iron surface, or use low potential electrons from iron and aqueous protons directly for sulfate reduction. In order to reveal the effects of SBS treatment in more detail, metagenomic analysis was performed with pipe-associated solids (PAS scraped from a pipe section upstream (PAS-616P and downstream (PAS-821TP of the SBS injection point. A major SBS-induced change in microbial community composition and in affiliated hynL genes for the large subunit of [NiFe] hydrogenase was the appearance of sulfur-metabolizing Epsilonproteobacteria of the genera Sulfuricurvum and Sulfurovum. These are chemolithotrophs, which oxidize sulfide or sulfur with O2 or reduce sulfur with H2. Because O2 was absent, this class likely catalyzed reduction of sulfur (S0 originating from the metabolism of bisulfite with cathodic H2 (or low potential electrons and aqueous protons originating from the corrosion of steel (Fe0. Overall this accelerates reaction of of S0 and Fe0 to form FeS, making this class a potentially powerful contributor to microbial corrosion. The PAS-821TP metagenome also had increased fractions of Deltaproteobacteria including the SRB Desulfomicrobium and Desulfocapsa. Altogether, SBS increased the fraction of hydrogen-utilizing Delta- and Epsilonproteobacteria in brackish-water-transporting pipelines, potentially stimulating anaerobic pipeline corrosion if dosed in excess of the intended oxygen scavenger function.

  4. Metagenomic Analysis Indicates Epsilonproteobacteria as a Potential Cause of Microbial Corrosion in Pipelines Injected with Bisulfite.

    Science.gov (United States)

    An, Dongshan; Dong, Xiaoli; An, Annie; Park, Hyung S; Strous, Marc; Voordouw, Gerrit

    2016-01-01

    Sodium bisulfite (SBS) is used as an oxygen scavenger to decrease corrosion in pipelines transporting brackish subsurface water used in the production of bitumen by steam-assisted gravity drainage. Sequencing 16S rRNA gene amplicons has indicated that SBS addition increased the fraction of the sulfate-reducing bacteria (SRB) Desulfomicrobium, as well as of Desulfocapsa, which can also grow by disproportionating sulfite into sulfide, sulfur, and sulfate. SRB use cathodic H2, formed by reduction of aqueous protons at the iron surface, or use low potential electrons from iron and aqueous protons directly for sulfate reduction. In order to reveal the effects of SBS treatment in more detail, metagenomic analysis was performed with pipe-associated solids (PAS) scraped from a pipe section upstream (PAS-616P) and downstream (PAS-821TP) of the SBS injection point. A major SBS-induced change in microbial community composition and in affiliated hynL genes for the large subunit of [NiFe] hydrogenase was the appearance of sulfur-metabolizing Epsilonproteobacteria of the genera Sulfuricurvum and Sulfurovum. These are chemolithotrophs, which oxidize sulfide or sulfur with O2 or reduce sulfur with H2. Because O2 was absent, this class likely catalyzed reduction of sulfur (S(0)) originating from the metabolism of bisulfite with cathodic H2 (or low potential electrons and aqueous protons) originating from the corrosion of steel (Fe(0)). Overall this accelerates reaction of of S(0) and Fe(0) to form FeS, making this class a potentially powerful contributor to microbial corrosion. The PAS-821TP metagenome also had increased fractions of Deltaproteobacteria including the SRB Desulfomicrobium and Desulfocapsa. Altogether, SBS increased the fraction of hydrogen-utilizing Delta- and Epsilonproteobacteria in brackish-water-transporting pipelines, potentially stimulating anaerobic pipeline corrosion if dosed in excess of the intended oxygen scavenger function. PMID:26858705

  5. Responsivity to dyslexia training indexed by the N170 amplitude of the brain potential elicited by word reading.

    Science.gov (United States)

    Fraga González, G; Žarić, G; Tijms, J; Bonte, M; Blomert, L; Leppänen, P; van der Molen, M W

    2016-07-01

    The present study examined training effects in dyslexic children on reading fluency and the amplitude of N170, a negative brain-potential component elicited by letter and symbol strings. A group of 18 children with dyslexia in 3rd grade (9.05±0.46years old) was tested before and after following a letter-speech sound mapping training. A group of 20 third-grade typical readers (8.78±0.35years old) performed a single time on the same brain potential task. The training was differentially effective in speeding up reading fluency in the dyslexic children. In some children, training had a beneficial effect on reading fluency ('improvers') while a training effect was absent in others ('non-improvers'). Improvers at pre-training showed larger N170 amplitude to words compared to non-improvers. N170 amplitude decreased following training in improvers but not in non-improvers. But the N170 amplitude pattern in improvers continued to differ from the N170 amplitude pattern across hemispheres seen in typical readers. Finally, we observed a positive relation between the decrease in N170 amplitude and gains in reading fluency. Collectively, the results that emerged from the present study indicate the sensitivity of N170 amplitude to reading fluency and its potential as a predictor of reading fluency acquisition. PMID:27200495

  6. Rapid synthesis and purification of carbon-11 labelled DOPA: a potential agent for brain studies

    International Nuclear Information System (INIS)

    A rapid method for preparation and purification of β-(3,4-dihydroxyphenyl)-D,L-α-alanine-1-11C(11C-DOPA), using 11CO2 as the radioactive precursor is described. Carboxylation of an α-lithioisocyanide, containing protected hydroxylic groups, was followed by a three-step hydrolysis of the intermediate αioscyano carboxylic acid. Preliminary experiments in rats indicate that the compound is preferentially decarboxylated in brain areas rich in dopamine containing neurons. (author)

  7. Magnetic resonance imaging indicators of blood-brain barrier and brain water changes in young rats with kaolin-induced hydrocephalus

    Directory of Open Access Journals (Sweden)

    Del Bigio Marc R

    2011-08-01

    Full Text Available Abstract Background Hydrocephalus is associated with enlargement of cerebral ventricles. We hypothesized that magnetic resonance (MR imaging parameters known to be influenced by tissue water content would change in parallel with ventricle size in young rats and that changes in blood-brain barrier (BBB permeability would be detected. Methods Hydrocephalus was induced by injection of kaolin into the cisterna magna of 4-week-old rats, which were studied 1 or 3 weeks later. MR was used to measure longitudinal and transverse relaxation times (T1 and T2 and apparent diffusion coefficients in several regions. Brain tissue water content was measured by the wet-dry weight method, and tissue density was measured in Percoll gradient columns. BBB permeability was measured by quantitative imaging of changes on T1-weighted images following injection of gadolinium diethylenetriamine penta-acetate (Gd-DTPA tracer and microscopically by detection of fluorescent dextran conjugates. Results In nonhydrocephalic rats, water content decreased progressively from age 3 to 7 weeks. T1 and T2 and apparent diffusion coefficients did not exhibit parallel changes and there was no evidence of BBB permeability to tracers. The cerebral ventricles enlarged progressively in the weeks following kaolin injection. In hydrocephalic rats, the dorsal cortex was more dense and the white matter less so, indicating that the increased water content was largely confined to white matter. Hydrocephalus was associated with transient elevation of T1 in gray and white matter and persistent elevation of T2 in white matter. Changes in the apparent diffusion coefficients were significant only in white matter. Ventricle size correlated significantly with dorsal water content, T1, T2, and apparent diffusion coefficients. MR imaging showed evidence of Gd-DTPA leakage in periventricular tissue foci but not diffusely. These correlated with microscopic leak of larger dextran tracers. Conclusions MR

  8. Ambient new particle formation parameter indicates potential rise in future events

    Directory of Open Access Journals (Sweden)

    B. Bonn

    2009-01-01

    Full Text Available Atmospheric new particle formation is a general phenomenon observed over coniferous forests. So far nucleation is described as a function of gaseous sulfuric acid concentration only, which is unable to explain the observed seasonality of nucleation events at different measurement sites. Here we introduce a new nucleation parameter including ozone and water vapor concentrations as well as UV-B radiation as a proxy for OH radical formation. Applying this new parameter to field studies conducted at Finnish and German measurement sites it is found capable to predict the occurrence of nucleation events and their seasonal and annual variation indicating a significant role of organics. Extrapolation to possible future conditions of ozone, water vapor and organic concentrations leads to a significant potential increase in nucleation event number.

  9. Getting into the brain: Potential of nanotechnology in the management of NeuroAIDS.

    Science.gov (United States)

    Nair, Madhavan; Jayant, Rahul Dev; Kaushik, Ajeet; Sagar, Vidya

    2016-08-01

    In spite of significant advances in antiretroviral (ARV) therapy, the elimination of human immunodeficiency virus (HIV) reservoirs from the periphery and the central nervous system (CNS) remains a formidable task. The incapability of ARV to go across the blood-brain barrier (BBB) after systemic administration makes the brain one of the dominant HIV reservoirs. Thus, screening, monitoring, and elimination of HIV reservoirs from the brain remain a clinically daunting and key task. The practice and investigation of nanomedicine possesses potentials for therapeutics against neuroAIDS. This review highlights the advancements in nanoscience and nanotechnology to design and develop specific size therapeutic cargo for efficient navigation across BBB so as to recognize and eradicate HIV brain reservoirs. Different navigation and drug release strategies, their biocompatibility and efficacy with related challenges and future prospects are also discussed. This review would be an excellent platform to understand nano-enable multidisciplinary research to formulate efficient nanomedicine for the management of neuroAIDS. PMID:26944096

  10. MR cholangiopancreatography: technique, potential indications, and diagnostic features of benign, postoperative, and malignant conditions

    Energy Technology Data Exchange (ETDEWEB)

    Becker, C.D. [Department of Radiology, Division of Diagnostic and Interventional Radiology, University Hospital of Geneva, CH-1211 Geneva (Switzerland); Grossholz, M. [Department of Radiology, Division of Diagnostic and Interventional Radiology, University Hospital of Geneva, CH-1211 Geneva (Switzerland); Mentha, G. [Department of Surgery, University Hospital of Geneva, CH-1211 Geneva (Switzerland); Peyer, R. de [Division of Gastroenterology, University Hospital of Geneva, CH-1211 Geneva (Switzerland); Terrier, F. [Department of Radiology, Division of Diagnostic and Interventional Radiology, University Hospital of Geneva, CH-1211 Geneva (Switzerland)

    1997-08-01

    The objective of this article is to review technical aspects, discuss potential clinical indications for MR cholangiopancreatography (MRCP) and demonstrate the spectrum of diagnostic findings in benign, postoperative, and malignant conditions. We describe our current imaging protocol in comparison with other available techniques. Using a non-breath-hold, heavily T2-weighted fast-spin-echo (FSE) sequence with or without respiratory gating we obtained coronal and axial source images and maximum intensity projections (MIPs) in 102 patients with suspected abnormalities of the biliary or pancreatic ducts. Based on this series we demonstrate the diagnostic appearance of a variety of benign, postoperative, and malignant conditions of the biliary and pancreatic ducts and discuss potential clinical indications for MRCP. The non-breath-hold FSE technique enables a consistent image quality even in patients who cannot cooperate well. Respiratory gating increased the rate of diagnostic examinations from 79 to 95 %. Acquisition of coronal and axial source images enables detection of bile duct stones as small as 2 mm, although calculi that are impacted and not surrounded by hyperintense bile may sometimes be difficult to detect. The MIP reconstructions help to determine the level of obstruction in malignant jaundice, delineate anatomical variants and malformations, and to diagnose inflammatory conditions, e. g., sclerosing cholangitis, the Mirizzi syndrome and inflammatory changes in the main pancreatic duct. The MRCP technique also correctly demonstrates the morphology of bilio-enteric or bilio-biliary anastomoses. Because MRCP provides sufficient diagnostic information in a wide range of benign and malignant biliary and pancreatic disorders, it could obviate diagnostic endoscopic retrograde cholangiopancreatography (ERCP) in many clinical settings. The ERCP technique may be increasingly reserved for patients in whom nonsurgical interventional procedures are anticipated. (orig

  11. Changes of evoked potentials and evaluation of mild hypothermia for treatment of severe brain injury

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To observe the changes of evoked pote ntials after severe brain injury and the effect of mild hypothermia on acute sev ere brain injury.   Methods: A total of 44 patients with severe closed head injury (GCS 3-8, admitted within 10 hours from injury) admitted from May 1998 to March 1999 were selected for this study. All patients were admitted into the intensiv e care unit and divided into 2 groups, Group A (GCS 3-5) and Group B (GCS 6 -8). Patients were also randomly assigned to either normothermia or hypothermia subgroups. Patients in the hypothermia group were cooled to 32-34℃. Median nerve short-latency somatosensory evoked potentials (SLSEP) and brain stem aud itory evoked potentials (BAEP) were recorded before cooling and 4, 24, 48, 72, 9 6 and 120 hours, respectively after cooling and temperature resuming. SLSEP and BAEP were measured at the same time in the normothermia group (control group). T he changes of evoked potentials (EP) were analyzed by statistical methods.   Results: In the Group B, N20 amplitudes in SLSEP and I/V amplitudes in BAEP after mild hypothermia treatment in the hypothermia group dif fered significantly from those in the control group (P<0.05). However, in the Group A, no significant difference in all paramet ers was found.   Conclusions: These results demonstrate that mild hypothermia tr eatment (32-34℃) in the Group B has a significant neuroelectrophysiological effect on severe brain injury. Nevertheless, the effect of mild hypothermia in t he Group A is not apparent and needs further studying.

  12. Potential for early warning of maalria in India using NOAA-AVHRR based vegetation health indices

    Science.gov (United States)

    Dhiman, R. C.; Kogan, Felix; Singh, Neeru; Singh, R. P.; Dash, A. P.

    Malaria is still a major public health problem in India with about 1 82 million cases annually and 1000 deaths As per World Health Organization WHO estimates about 1 3 million Disability Adjusted Life Years DALYs are lost annually due to malaria in India Central peninsular region of India is prone to malaria outbreaks Meteorological parameters changes in ecological conditions development of resistance in mosquito vectors development of resistance in Plasmodium falciparum parasite and lack of surveillance are the likely reasons of outbreaks Based on satellite data and climatic factors efforts have been made to develop Early Warning System EWS in Africa but there is no headway in this regard in India In order to find out the potential of NOAA satellite AVHRR derived Vegetation Condition Index VCI Temperature Condition Index TCI and a cumulative indicator Vegetation Health Index VHI were attempted to find out their potential for development of EWS Studies were initiated by analysing epidemiological data of malaria vis-a-vis VCI TCI and VHI from Bikaner and Jaisalmer districts of Rajasthan and Tumkur and Raichur districts of Karnataka Correlation coefficients between VCI and monthly malaria cases for epidemic years were computed Positive correlation 0 67 has been found with one-month lag between VCI and malaria incidence in respect of Tumkur while a negative correlation with TCI -0 45 is observed In Bikaner VCI is found to be negatively related -0 71 with malaria cases in epidemic year of 1994 Weekly

  13. Antioxidant Potential of a Polyherbal Antimalarial as an Indicator of Its Therapeutic Value

    Directory of Open Access Journals (Sweden)

    Protus Arrey Tarkang

    2013-01-01

    Full Text Available Nefang is a polyherbal product composed of Mangifera indica (bark and leaf, Psidium guajava, Carica papaya, Cymbopogon citratus, Citrus sinensis, and Ocimum gratissimum (leaves, used for the treatment of malaria. Compounds with antioxidant activity are believed to modulate plasmodial infection. Antioxidant activity of the constituent aqueous plants extracts, in vitro, was evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH, total phenolic content (TPC, and ferric reducing antioxidant power (FRAP methods and, in vivo, Nefang (100 and 500 mg kg−1 activity was evaluated in carbon tetrachloride-induced oxidative stressed Wistar rats. Superoxide dismutase, catalase activities, and lipid peroxidation by the malondialdehyde and total proteins assays were carried out. P. guajava, M. indica leaf, and bark extracts had the highest antioxidant properties in all three assays, with no statistically significant difference. Rats treated with the carbon tetrachloride had a statistically significant decrease in levels of triglycerides, superoxide dismutase, and catalase (P<0.05 and increase in malondialdehyde activity, total protein levels, and liver and renal function markers, whereas rats treated with Nefang showed increased levels in the former and dose-dependent decrease towards normal levels in the later. These results reveal the constituent plants of Nefang that contribute to its in vivo antioxidant potential. This activity is a good indication of the therapeutic potential of Nefang.

  14. National valuation of monarch butterflies indicates an untapped potential for incentive-based conservation

    Science.gov (United States)

    Diffendorfer, Jay E.; Loomis, John B.; Ries, Leslie; Oberhauser, Karen; Semmens, Darius; Semmens, Brice; Butterfield, Bruce; Bagstad, Ken; Goldstein, Josh; Wiederholt, Ruscena; Mattsson, Brady; Thogmartin, Wayne E.

    2013-01-01

    The annual migration of monarch butterflies (Danaus plexippus) has high cultural value and recent surveys indicate monarch populations are declining. Protecting migratory species is complex because they cross international borders and depend on multiple regions. Understanding how much, and where, humans place value on migratory species can facilitate market-based conservation approaches. We performed a contingent valuation study of monarchs to understand the potential for such approaches to fund monarch conservation. The survey asked U.S. respondents about the money they would spend, or have spent, growing monarch-friendly plants, and the amount they would donate to monarch conservation organizations. Combining planting payments and donations, the survey indicated U.S. households valued monarchs as a total one-time payment of $4.78–$6.64 billion, levels similar to many endangered vertebrate species. The financial contribution of even a small percentage of households through purchases or donations could generate new funding for monarch conservation through market-based approaches.

  15. SERPINA4 is a novel independent prognostic indicator and a potential therapeutic target for colorectal cancer.

    Science.gov (United States)

    Sun, Hui-Min; Mi, Yu-Shuai; Yu, Fu-Dong; Han, Yang; Liu, Xi-Sheng; Lu, Su; Zhang, Yu; Zhao, Sen-Lin; Ye, Ling; Liu, Ting-Ting; Yang, Dao-Hua; Sun, Xiao-Feng; Qin, Xue-Bin; Zhou, Zong-Guang; Tang, Hua-Mei; Peng, Zhi-Hai

    2016-01-01

    Serpina family A member 4 (SERPINA4), also known as kallistatin, exerts important effects in inhibiting tumor growth and angiogenesis in many malignancies. However, the precise role of SERPINA4 in CRC has not been fully elucidated. The present study aimed to investigate the expression of SERPINA4 and its clinical significance in CRC. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analyses showed that the mRNA and protein expression of SERPINA4 in colorectal cancer (CRC) specimens was significantly decreased than that in adjacent normal mucosa. Immunohistochemistry (IHC) was conducted to characterize the expression pattern of SERPINA4 by using a tissue microarray (TMA) containing 327 archived paraffin-embedded CRC specimens. Statistical analyses revealed that decreased SERPINA4 expression was significantly associated with invasion depth, nodal involvement, distant metastasis, American Joint Committee on Cancer (AJCC) stage, and tumor differentiation. SERPINA4 was also an independent prognostic indicator of disease-free survival and overall survival in patients with CRC. Furthermore, the impact of altered SERPINA4 expression on CRC cells was analyzed with a series of in vitro and in vivo assays. The results demonstrated that SERPINA4 significantly inhibits malignant tumor progression and serves as a novel prognostic indicator and a potential therapeutic target for CRC. PMID:27648355

  16. Defining indicators to motorize block valves aiming to reduce potential leakage applied to OSBRA pipeline

    Energy Technology Data Exchange (ETDEWEB)

    Pires, L.F.G. [Pontificia Universidade Catolica do Rio de Janeiro (PUC-Rio), RJ (Brazil); Sousa, A.G.; Castro, N.C.; Spagnolo, R. [Petrobras Transporte S.A. (TRANSPETRO), Rio de Janeiro, RJ (Brazil)

    2009-07-01

    The discussion about motorizing block valves is a constant point being brought up when it is intended to control or reduce the amount of liquid leaking in the event of a pipe rupture. During the pipeline's project stage the installation of blocking valves along the pipeline must be taken into consideration to meet the operation and maintenance requirements as well as to reduce the potential amounts of volume being leaked. In existing pipelines, the main concern is the definition of which valves are candidates to be motorized. In both situations criteria should be established to define this choice. A math algorithm was developed to define the potential leakage due to gravity along the pipeline profile where the influence of a valve over another is verified, as well as the contribution of the check valves existing in the pipeline. The present work defines a parameter based on the extension protected by the valve and the reduction of the potential leakage. This parameter is then fed to a worksheet where the efficiency indicators are calculated to each valve eligible to be motorized. It also takes into consideration factors relative to the valve location, such as the environmental sensitivity, risk assessment, social diagnosis and device's proximity to contingency resources. Finally, after considering all the above aspects, it's possible to come up with a final classification, recommending specific valves to be prioritized on an eventual process of motorization adequacies. This methodology was applied, experimentally on a pipe segment of TRANSPETRO's Sao Paulo-Brasilia pipeline - OSBRA , where it proved to be an important technological and management tool. (author)

  17. Usefulness of brain atlases in neuroradiology: Current status and future potential.

    Science.gov (United States)

    Nowinski, Wieslaw L

    2016-08-01

    Human brain atlases, although prevalent in medical education and stereotactic and functional neurosurgery, are not yet applied practically in neuroradiology. In a step towards introducing brain atlases to neuroradiology, we discuss nine different situations of potential atlas use: (1) to support interpretation of brain scans with clearly visible structures (to increase confidence of non-neuroradiologists); (2) to delineate and label scans of low anatomical content (with indiscernible or poorly visible anatomy); (3) to assist in generating the structured report; (4) to assist in interpreting small deep lesions, since an atlas's anatomical parcellation is higher than that of the interpreted scan; (5) to approximate distorted due to pathology (and unknown to the interpreter) anatomy and label it; (6) to cope with data explosion; (7) to assist in the interpretation of functional scans (to label the activation foci with the underlying anatomy and Brodmann's areas); (8) to support ischemic stroke image handling by means of atlases of anatomy and blood supply territories; and (9) to communicate image interpretation results (diagnosis) to others. The usefulness of the atlas for automatic structure identification, localisation, delineation, labelling and quantification, as well as for reporting and communication, potentially increases the interpreter's efficiency and confidence, as well as expedites image interpretation. PMID:27154190

  18. Radiotracer properties determined by high performance liquid chromatography: a potential tool for brain radiotracer discovery

    International Nuclear Information System (INIS)

    Introduction: Previously, development of novel brain radiotracers has largely relied on simple screening tools. Improved selection methods at the early stages of radiotracer discovery and an increased understanding of the relationships between in vitro physicochemical and in vivo radiotracer properties are needed. We investigated if high performance liquid chromatography (HPLC) methodologies could provide criteria for lead candidate selection by comparing HPLC measurements with radiotracer properties in humans. Methods: Ten molecules, previously used as radiotracers in humans, were analysed to obtain the following measures: partition coefficient (Log P); permeability (Pm); percentage of plasma protein binding (%PPB); and membrane partition coefficient (Km). Relationships between brain entry measurements (Log P, Pm and %PPB) and in vivo brain percentage injected dose (%ID); and Km and specific binding in vivo (BPND) were investigated. Log P values obtained using in silico packages and flask methods were compared with Log P values obtained using HPLC. Results: The modelled associations with %ID were stronger for %PPB (r2=0.65) and Pm (r2=0.77) than for Log P (r2=0.47) while 86% of BPND variance was explained by Km. Log P values were variable dependant on the methodology used. Conclusions: Log P should not be relied upon as a predictor of blood-brain barrier penetration during brain radiotracer discovery. HPLC measurements of permeability, %PPB and membrane interactions may be potentially useful in predicting in vivo performance and hence allow evaluation and ranking of compound libraries for the selection of lead radiotracer candidates at early stages of radiotracer discovery.

  19. Brain-potential analysis of visual word recognition in dyslexics and typically reading children

    Directory of Open Access Journals (Sweden)

    Gorka eFraga González

    2014-06-01

    Full Text Available The specialization of visual brain areas for fast processing of printed words plays an important role in the acquisition of reading skills. Dysregulation of these areas may be among the deficits underlying developmental dyslexia. The present study examines the specificity of word activation in dyslexic children in 3rd grade by comparing early components of brain potentials elicited by visually presented words vs. strings of meaningless letter-like symbols. Results showed a more pronounced N1 component for words compared to symbols for both groups. The dyslexic group revealed larger left-lateralized, word-specific N1 responses than the typically reading group. Furthermore, positive correlations between N1 amplitudes and reading fluency were found in the dyslexic group. Our results support the notion of N1 as a sensitive index of visual word processing involved in reading fluency.

  20. Proteomics analysis after traumatic brain injury in rats: the search for potential biomarkers

    Directory of Open Access Journals (Sweden)

    Jun Ding

    2015-04-01

    Full Text Available Many studies of protein expression after traumatic brain injury (TBI have identified biomarkers for diagnosing or determining the prognosis of TBI. In this study, we searched for additional protein markers of TBI using a fluid perfusion impact device to model TBI in S-D rats. Two-dimensional gel electrophoresis and mass spectrometry were used to identify differentially expressed proteins. After proteomic analysis, we detected 405 and 371 protein spots within a pH range of 3-10 from sham-treated and contused brain cortex, respectively. Eighty protein spots were differentially expressed in the two groups and 20 of these proteins were identified. This study validated the established biomarkers of TBI and identified potential biomarkers that could be examined in future work.

  1. Organic Inclusions as an Indicator of Oil/Gas Potential Assessment of Carbonate Reservoir Beds

    Institute of Scientific and Technical Information of China (English)

    施继锡; 兰文波

    1993-01-01

    Organic inclusions could be formed at the stages of either primary or secondary migration of hydrocarbons so long as mineral crystallization or recrystallization takes place in the sediments, presenting a direct indicator of oil/gas evolution, migration and abundance.Based on the strdy of organic inclusions in carbonate-type reser voir beds of commercial importance from North China ,Xingjing ,North Jiangsu, Sichuan and Guizhou in China ,many inclusion parameters for oil/gas potential assessment of carbonate reservoir beds are summarized in this paper, including;1) Types of organic inclusion; Ccmmercially important oil beds are characterized by inclusions consisting of either pure liquid hydrocarbons or liquid plus minor gaseous hydrocarbons, while commercially important gas reservoirs are characterized by inclusions consisting of either pure gaseous hydrocarbons or gas plus minor liquid hydrocarbons.2)Quantity of organic inclusions:The num-ber of organic inclusions in commercially important oil/gas reservoirs is over 60% of the total inclusion percent-tage.3)Temperature of saline inclusions .The homogenization temperatures of contemporaneous saline inclu-sions in oil reservoirs range from 91-161℃, while in gas reservoirs from 150-250℃).4) Inclusion composition: In commercially important oil reservoirs, C1/C2=2-10,C1/C3=2-4,C1/C4=2-21,(C2-C4)/(C1-C4)(%)>20,(CH4+CO+H2)/CO2(molecules/g)=0.5-1.0,and in C2-C3-nC4 triangle diagram there should be an upside-down triangle with the apex within the ellipse, while in commercial gas reservoirs, C1/C2=10-35,C1/C3=14-82,C1/C4=21-200,(C2-C4)/(C1-C4)(%)1,and there would be an upright triangle with the apex within the ellipse.The abovementioned parameters have been used to evaluate a number of other unknown wells or regions and the results are very satisfactory.It is valid to use organic inclusions as an indicator to assess the oil/gas potential during oil/gas exploration and prospecting,This approach is effective

  2. Bivalves as indicators of environmental variation and potential anthropogenic impacts in the southern Barents Sea.

    Science.gov (United States)

    Carroll, Michael L; Johnson, Beverly J; Henkes, Gregory A; McMahon, Kelton W; Voronkov, Andrey; Ambrose, William G; Denisenko, Stanislav G

    2009-01-01

    Identifying patterns and drivers of natural variability in populations is necessary to gauge potential effects of climatic change and the expected increases in commercial activities in the Arctic on communities and ecosystems. We analyzed growth rates and shell geochemistry of the circumpolar Greenland smooth cockle, Serripes groenlandicus, from the southern Barents Sea over almost 70 years between 1882 and 1968. The datasets were calibrated via annually-deposited growth lines, and growth, stable isotope (delta(18)O, delta(13)C), and trace elemental (Mg, Sr, Ba, Mn) patterns were linked to environmental variations on weekly to decadal scales. Standardized growth indices revealed an oscillatory growth pattern with a multi-year periodicity, which was inversely related to the North Atlantic Oscillation Index (NAO), and positively related to local river discharge. Up to 60% of the annual variability in Ba/Ca could be explained by variations in river discharge at the site closest to the rivers, but the relationship disappeared at a more distant location. Patterns of delta(18)O, delta(13)C, and Sr/Ca together provide evidence that bivalve growth ceases at elevated temperatures during the fall and recommences at the coldest temperatures in the early spring, with the implication that food, rather than temperature, is the primary driver of bivalve growth. The multi-proxy approach of combining the annually integrated information from the growth results and higher resolution geochemical results yielded a robust interpretation of biophysical coupling in the region over temporal and spatial scales. We thus demonstrate that sclerochronological proxies can be useful retrospective analytical tools for establishing a baseline of ecosystem variability in assessing potential combined impacts of climatic change and increasing commercial activities on Arctic communities. PMID:19394657

  3. Simulation of Potential Production and Optimum Population Quantitative Indices for the Second Hybrid Rice

    Institute of Scientific and Technical Information of China (English)

    YAN Li-jiao; YAO Zhong; ZHENG Zhi-ming; LI Hua-bin

    2006-01-01

    The article established the HDRICE model by modifying the structure of the ORYZA1 model and revising its parameters by field experiments. The HDRICE model consists of the modules of morphological development of rice, daily dry matter accumulation and partitioning, daily CO2 assimilation of the canopy, leaf area, and tiller development. The model preferably simulated the dynamic rice development because of the thorough integration of the effects of temperature and light on the rates of rice development, photosynthesis, respiration, and. other ecophysiological processes. In addition, this model has attainable grain yield in the test experiment that showed the potential yield of cultivar Xieyou 46 ranged from 11 to 13 tons ha-1. Besides, the model was used to optimize the combinations of the transplanting date, seedling age and density for cultivar Xieyou 46 at Jinhua area, and the population quantitative indices to attain the potential yield such as maximum stems, effective panicles, filled grain number/leaf area, and so on. The result showed that the combination of transplanting date on July 25, seedling age of 35 days and base seedling density of 1.33 × 106ha-1 is the optimum combination for the second hybrid rice production in Jinhua County, China. And the maximum stems, the effective panicles, the filled grain per panicle, the peak of optimum LAI, LAI in later filling stage, and the filled grain number/leaf were 6.03 × 106 ha, 3.99 × 106 ha,119.2, 8.59, 5-6, and 0.64, respectively.

  4. Analysis of brain-stem auditory evoked potential and visual evoked potential in patients with Parkinson disease

    Institute of Scientific and Technical Information of China (English)

    Qiaorong Deng; Jianzhong Deng; Yanmin Zhao; Xiaohai Yan; Pin Chen

    2006-01-01

    BACKGROUND: With the development of neuroelectrophysiology, it had been identified that all kinds of evoked potentials might reflect the functional status of corresponding pathway. Evoked potentials recruited in the re search of PD, it can be known whether other functional pathway of nervous system is impaired. OBJECTIVE: To observe whether brainstem auditory and visual passageway are impaired in patients with Parkinson disease (PD), and compare with non-PD patients concurrently. DESIGN: A non-randomized concurrent controlled observation. SETTINGS: Henan Provincial Tumor Hospital; Anyang District Hospital. PARTICIPANTS: Thirty-two cases of PD outpatients and inpatients, who registered in the Department of Neurology, Anyang District Hospital from October 1997 to February 2006, were enrolled as the PD group, including 20 males and 12 females, aged 50-72 years old. Inclusive criteria: In accordance with the diagnostic criteria of PD recommended by the dyskinesia and PD group of neurology branch of Chinese Medical Association. Patients with diseases that could cause Parkinson syndrome were excluded by CT scanning or MRI examination. Meanwhile, 30 cases with non-neurological disease were selected from the Department of Internal Medicine of our hospital as the control group, including 19 males and 11 females, aged 45-70 years old. Including criteria: Without history of neurological disease or psychiatric disease; showing normal image on CT. And PD, Parkinson syndrome and Parkinsonism-plus were excluded by professional neurologist. All the patients were informed and agreed with the examination and clinical observation. METHODS: The electrophysiological examination and clinical observation of the PD patients and controls were conducted. The Reporter type 4-channel evoked potential machine (Italy) was used to check brain-stem auditory evoked potential (BAEP) and visual evoked potential (VEP). Why to be examined was explained to test taker. BAEP recording electrode was plac

  5. The Potential Impact of Biofield Treatment on Human Brain Tumor Cells: A Time-Lapse Video Microscopy

    OpenAIRE

    Trivedi, Mahendra Kumar

    2015-01-01

    Study background: Glioblastoma (GBM) is the most common subtype of primary brain tumor in adults. The aim was to evaluate the impact of biofield treatment potential on human GBM and non-GBM brain cells using two time-lapse video microscopy technique. Methods: The human brain tumor, GBM cultured cells were divided into two groups viz. GBM control and GBM treatment. Similarly, human normal brain cultured cells (non-GBM) were taken and divided into two groups viz. non- GBM control ...

  6. Biomarkers of clinical responsiveness in brain tumor patients : progress and potential.

    Science.gov (United States)

    El-Jawahri, Areej; Patel, Disha; Zhang, Min; Mladkova, Nikol; Chakravarti, Arnab

    2008-01-01

    Gliomas are the most common primary brain tumors in adults. Anaplastic astrocytoma and glioblastoma multiforme represent malignant astrocytomas, which are the most common type of malignant gliomas. Despite research efforts in cancer therapy, the prognosis of patients with malignant gliomas remains poor. Research efforts in recent years have focused on investigating the cellular, molecular, and genetic pathways involved in the progression of malignant gliomas. As a result, biomarkers have emerged as diagnostic, predictive, and prognostic tools that have the potential to transform the field of brain tumor diagnostics. An increased understanding of the important molecular pathways that have been implicated in the progression of malignant gliomas has led to the identification of potential diagnostic, prognostic, and predictive biomarkers, some bearing clinical implications for targeted therapy. Some of the most promising biomarkers to date include loss of chromosomes 1p/19q in oligodendrogliomas and expression of O-6-methylguanine-DNA methyltransferase (MGMT) or epidermal growth factor receptor (EGFR) status in glioblastomas. Other promising biomarkers in glioma research include glial fibrillary acidic protein, galectins, Kir potassium channel proteins, angiogenesis, and apoptosis pathway markers. Research into the clinical relevance and applicability of such biomarkers has the potential to revolutionize our approach to the diagnosis and treatment of patients with malignant gliomas. PMID:18652516

  7. Current Clinical Applications and Future Potential of Diffusion Tensor Imaging in Traumatic Brain Injury.

    Science.gov (United States)

    Strauss, Sara; Hulkower, Miriam; Gulko, Edwin; Zampolin, Richard L; Gutman, David; Chitkara, Munish; Zughaft, Malka; Lipton, Michael L

    2015-12-01

    In the setting of acute central nervous system (CNS) emergencies, computed tomography (CT) and conventional magnetic resonance imaging (MRI) play an important role in the identification of life-threatening intracranial injury. However, the full extent or even presence of brain damage frequently escapes detection by conventional CT and MRI. Advanced MRI techniques such as diffusion tensor imaging (DTI) are emerging as important adjuncts in the diagnosis of microstructural white matter injury in the acute and postacute brain-injured patient. Although DTI aids in detection of brain injury pathology, which has been repeatedly associated with typical adverse clinical outcomes, the evolution of acute changes and their long-term prognostic implications are less clear and the subject of much active research. A major aim of current research is to identify imaging-based biomarkers that can identify the subset of TBI patients who are at risk for adverse outcome and can therefore most benefit from ongoing care and rehabilitation as well as future therapeutic interventions.The aim of this study is to introduce the current methods used to obtain DTI in the clinical setting, describe a set of common interpretation strategies with their associated advantages and pitfalls, as well as illustrate the clinical utility of DTI through a set of specific patient scenarios. We conclude with a discussion of future potential for the management of TBI.

  8. Steady State Visual Evoked Potential Based Brain-Computer Interface for Cognitive Assessment

    DEFF Research Database (Denmark)

    Westergren, Nicolai; Bendtsen, Rasmus L.; Kjær, Troels W.;

    2016-01-01

    decline is important. Cognitive decline may be detected using fullyautomated computerized assessment. Such systems will provide inexpensive and widely available screenings of cognitive ability. The aim of this pilot study is to develop a real time steady state visual evoked potential (SSVEP) based brain-computer...... interface (BCI) for neurological cognitive assessment. It is intended for use by patients who suffer from diseases impairing their motor skills, but are still able to control their gaze. Results are based on 11 healthy test subjects. The system performance have an average accuracy of 100% ± 0%. The test...

  9. [Music-Acoustic Signals Controlled by Subject's Brain Potentials in the Correction of Unfavorable Functional States].

    Science.gov (United States)

    Fedotchev, A I; Bondar, A T; Bakhchina, A V; Parin, S B; Polevaya, S A; Radchenko, G S

    2016-01-01

    Literature review and the results of own studies on the development and experimental testing of musical EEG neurofeedback technology are presented. The technology is based on exposure of subjects to music or music-like signals that are organized in strict accordance with the current values of brain potentials of the patient. The main attention is paid to the analysis of the effectiveness of several versions of the technology, using specific and meaningful for the individual narrow-frequency EEG oscillators during the correction of unfavorable changes of the functional state. PMID:27149824

  10. Li zoning in zircon as a potential geospeedometer and peak temperature indicator

    Science.gov (United States)

    Trail, Dustin; Cherniak, Daniele J.; Watson, E. Bruce; Harrison, T. Mark; Weiss, Benjamin P.; Szumila, Ian

    2016-03-01

    . Discrete 10 μm concentration zones of Li within zircon may be partially preserved at 700 °C for tens to hundreds of years, and at 450 °C for millions of years. In this regard, Li zoning in zircon holds significant potential as a geospeedometer, and in some instances as a qualitative indicator of the maximum temperature experienced by the zircon.

  11. Excess air in groundwater as a potential indicator of past environmental changes

    International Nuclear Information System (INIS)

    Dissolved noble gases in groundwater are used to reconstruct paleotemperature, but also yield information about 'excess air', a component of dissolved gases in excess of solubility equilibrium, derived from dissolution of trapped air in the ground. A good characterization of the excess air component is necessary not only to obtain reliable noble gas temperatures, but also to investigate the potential of excess air as a proxy for past environmental conditions. Two excess air related quantities can be derived from groundwater noble gas data sets: The initial air/water ratio and the pressure exerted on the entrapped air. Under recharge conditions typical for many aquifers, the excess of dissolved gases, expressed by the relative Ne excess ΔNe, is mainly determined by the hydrostatic pressure on the entrapped air. Thus, we suggest that ΔNe is essentially a measure of the amplitude of water table fluctuations in the recharge area. Comparing data sets from three aquifers in temperate, humid latitudes and three aquifers in tropical, semi-arid regions, we find that ΔNe is generally higher in the tropical aquifers, possibly related to larger water table fluctuations in these aquifers characterized by deep unsaturated zones. Whereas ΔNe shows little temporal variation in the mid-latitude aquifers, there is a strong signal of higher ΔNe in the paleowaters of the tropical aquifers as compared to water recharged under modern climate conditions. This finding may indicate a higher variability of recharge in the past at the studied tropical sites. (author)

  12. Event-related potential indices of congruency sequence effects without feature integration or contingency learning confounds.

    Science.gov (United States)

    Larson, Michael J; Clayson, Peter E; Kirwan, C Brock; Weissman, Daniel H

    2016-06-01

    The congruency effect in Stroop-like tasks (i.e., increased response time and reduced accuracy in incongruent relative to congruent trials) is often smaller when the previous trial was incongruent as compared to congruent. This congruency sequence effect (CSE) is thought to reflect cognitive control processes that shift attention to the target and/or modulate the response engendered by the distracter differently after incongruent relative to congruent trials. The neural signatures of CSEs are therefore usually attributed to cognitive control processes that minimize distraction from irrelevant stimuli. However, CSEs in previous functional neuroimaging studies were ubiquitously confounded with feature integration and/or contingency learning processes. We therefore investigated whether a neural CSE can be observed without such confounds in a group of healthy young adults (n = 56). To this end, we combined a prime-probe task that lacks such confounds with high-density ERPs to identify, for the first time, the neural time course of confound-minimized CSEs. Replicating recent behavioral findings, we observed strong CSEs in this task for mean response time and mean accuracy. Critically, conceptually replicating prior ERP results from confounded tasks, we also observed a CSE in both the parietal conflict slow potential (conflict SP) and the frontomedial N450. These findings indicate for the first time that neural CSEs as indexed by ERPs can be observed without the typical confounds. More broadly, the present study provides a confound-minimized protocol that will help future researchers to better isolate the neural bases of control processes that minimize distraction from irrelevant stimuli. PMID:26854028

  13. Mechanisms underlying syntactic and semantic processing of Chinese simple sentences Evidence from event-related brain potentials

    Institute of Scientific and Technical Information of China (English)

    Huanhai Fang; Ming Zhao

    2011-01-01

    This study sought to test the processing of three types of sentences in Chinese, as correct sentences, semantic violation sentences, and sentences containing semantic and syntactic violations, based on the following sentence pattern: "subject (noun) + yi/gang/zheng + predicate (verb)". Event-related potentials on the scalp were recorded using 32-channel electroencephalography. Compared with correct sentences, target words elicited an early left anterior negativity (N400) and a later positivity (P600) over frontal, central and temporal sites in sentences involving semantic violations. In addition, when sentences contained both semantic and syntactic violations, the target words elicited a greater N400 and P600 distributed in posterior brain areas. These results indicate that Chinese sentence comprehension involves covert grammar processes.

  14. The UCLA Study of Children with Moderate-to-Severe Traumatic Brain Injury: Event-Related Potential Measure of Interhemispheric Transfer Time

    OpenAIRE

    Ellis, MU; Marion, SD; McArthur, DL; Babikian, T; Giza, C; Kernan, CL; NEWMAN;, N.; Moran, L.; Akarakian, R; Houshiarnejad, A; Mink, R; Johnson, J; Babbitt, CJ; Olsen, A.; Asarnow, RF

    2016-01-01

    Traumatic brain injury (TBI) frequently results in diffuse axonal injury and other white matter damage. The corpus callosum (CC) is particularly vulnerable to injury following TBI. Damage to this white matter tract has been associated with impaired neurocognitive functioning in children with TBI. Event-related potentials can identify stimulus-locked neural activity with high temporal resolution. They were used in this study to measure interhemispheric transfer time (IHTT) as an indicator of C...

  15. Quantitative MRI analysis of the brain after twenty-two years of neuromyelitis optica indicates focal tissue damage

    DEFF Research Database (Denmark)

    Aradi, Mihaly; Koszegi, Edit; Orsi, Gergely;

    2013-01-01

    BACKGROUND: The long-term effect of neuromyelitis optica (NMO) on the brain is not well established. METHODS: After 22 years of NMO, a patient's brain was examined by quantitative T1- and T2-weighted mono- and biexponential diffusion and proton spectroscopy. It was compared to 3 cases with short...

  16. Motivation and semantic context affect brain error-monitoring activity: an event-related brain potentials study.

    Science.gov (United States)

    Ganushchak, Lesya Y; Schiller, Niels O

    2008-01-01

    During speech production, we continuously monitor what we say. In situations in which speech errors potentially have more severe consequences, e.g. during a public presentation, our verbal self-monitoring system may pay special attention to prevent errors than in situations in which speech errors are more acceptable, such as a casual conversation. In an event-related potential study, we investigated whether or not motivation affected participants' performance using a picture naming task in a semantic blocking paradigm. Semantic context of to-be-named pictures was manipulated; blocks were semantically related (e.g., cat, dog, horse, etc.) or semantically unrelated (e.g., cat, table, flute, etc.). Motivation was manipulated independently by monetary reward. The motivation manipulation did not affect error rate during picture naming. However, the high-motivation condition yielded increased amplitude and latency values of the error-related negativity (ERN) compared to the low-motivation condition, presumably indicating higher monitoring activity. Furthermore, participants showed semantic interference effects in reaction times and error rates. The ERN amplitude was also larger during semantically related than unrelated blocks, presumably indicating that semantic relatedness induces more conflict between possible verbal responses. PMID:17920932

  17. Global to local genetic diversity indicators of evolutionary potential in tree species within and outside forests

    DEFF Research Database (Denmark)

    Graudal, Lars; Aravanopoulos, Filippos; Bennadji, Zohra;

    2014-01-01

    -monitoring schemes. Here, we provide a review and an assessment of the different attempts made to provide such indicators for tree genetic diversity from the global level down to the level of the management unit. So far, no generally accepted indicators have been provided as international standards, nor tested...... distributions (patterns of genetic variation of key adaptive traits in the ecological space) of selected species is a realistic way of assessing the trend of intra-specific variation, and thus provides a state indicator of tree genetic diversity also able to reflect possible pressures threatening genetic...... independently of state indicators. A coherent set of indicators covering diversity-productivity-knowledge-management based on the genecological approach is proposed for application on appropriate groups of tree species in the wild and in cultivation worldwide. These indicators realistically reflect the state...

  18. Potential brain death organ donors - challenges and prospects: A single center retrospective review

    Directory of Open Access Journals (Sweden)

    Yousef Al-Maslamani

    2014-01-01

    Full Text Available Organ donation after brain death (BD is a major source for obtaining transplantable organs for patients with end-stage organ disease (ESOD. This retrospective, descriptive study was carried out on all potential BD patients admitted in different intensive care units (ICUs of the Hamad medical Corporation (HMC, Doha, Qatar during a period from January 2011 to April 2012. Our aim was to evaluate various demographic criteria and challenges of organ donation among potential BD organ donors and plan a strategy to improve the rate of organ donation in Qatar. Various aspects of BD patients in the ICUs and their possible effects on organ donation were studied. The time intervals analyzed to determine the possible causes of delay of organ retrieval were: time of diagnosing fixed dilated pupils in the ICU, to performing the first BD test, then to the second BD test, to family approach, to organ retrieval and/or circulatory death (CD without organ retrieval. There were a total of 116 potential BD organ donors of whom 96 (82.75% were males and 20 (17.25% were females. Brain hemorrhage and head injury contributed to 37 (31.9% and 32 (27.6% BD cases, respectively. Time interval between diagnosing fixed dilated pupil and performing the first test of BD was delayed >24 h in 79% of the cases and between the first and second BD tests was >6 h in 70.8% of the cases. This delay is not compatible with the Hamad Medical Corporation (HMC policy for BD diagnosis and resulted in a low number of organs retrieved. BD organ donation, a potential source for organs to save patients with ESOD has several pitfalls and every effort should be made to increase the awareness of the public as well as medical personnel to optimize donation efficacy.

  19. The Potential of Systems Thinking in Teacher Reform as Theorized for the Teaching Brain Framework

    Science.gov (United States)

    Rodriguez, Vanessa

    2013-01-01

    The teaching brain is a dynamic system that is in constant interaction with the learning brain. If we fail to explore the teaching brain we will continue to design educational reform policies that ignore the most important lens in the classroom: the teachers'. Master teachers recognize their perspective and leverage their teaching brains to embody…

  20. World Cities of Scientific Knowledge: Systems, Networks and Potential Dynamics. An Analysis Based on Bibliometric Indicators

    DEFF Research Database (Denmark)

    Matthiessen, Christian Wichmann; Schwarz, Annette Winkel; Find, Søren

    2010-01-01

    of coauthorship between researchers in different cities is an indicator of links and respect, and the number of citations of papers produced by researchers located in each city is an indicator of respect. Finally, one research discipline is selected for an experiment in forecasting future hot spots of research....

  1. World Cities of Scientific Knowledge: Systems, Networks and Potential Dynamics. An Analysis Based on Bibliometric Indicators

    DEFF Research Database (Denmark)

    Matthiessen, Christian Wichmann; Schwarz, Annette Winkel; Find, Søren

    2010-01-01

    -authorships between researchers in different cities is an indicators of links and respect, and the number of citations to papers produced by researchers located in each city is an indicator of respect. Finally, one research discipline is selected for an experiment in forecasting future hot spots of research....

  2. GIS-fuzzy logic approach for building indices: regional feasibility and natural potential of ranching in tropical wetland

    OpenAIRE

    Sandra Aparecida Santos; Helano Póvoa Lima; Humberto Perotto Baldivieso; Luíz Orcirio Oliveira; Walfrido Moraes Tomás

    2015-01-01

    The regional feasibility of ranching (RFR) index was obtained in order to evaluate the productive potential of farms in the Pantanal. Five indicators were selected by expert and employed for the developing of the index. One of the five indicators corresponded to the natural potential for livestock ranching (NPLR) index which was generated by GIS-fuzzy logic. Fuzzy inference process, involving definitions of membership functions, fuzzy set operations and inference rules was implemented and val...

  3. Some observations indicating a low brain uptake of (/sup 3/H)Nle/sup 11/-Substance P

    Energy Technology Data Exchange (ETDEWEB)

    Landgraf, R.; Klauschenz, E.; Bienert, M.; Ermisch, A.; Oehme, P. (Akademie der Wissenschaften der DDR, Berlin. Inst. fuer Wirkstofforschung; Karl-Marx-Universitaet, Leipzig (German Democratic Republic). Sektion Biowissenschaften; Deutsche Hochschule fuer Koerperkultur, Leipzig (German Democratic Republic))

    1983-02-01

    The studies concerning the problem of whether an exogenous neuropeptide is able to enter the brain tissue were extended to the undecapeptide Substance P (SP). The amount of radioactivity 15 s after intracarotid injection of (/sup 3/H)Nle/sup 11/-SP or (/sup 14/C)inulin was determined in 18 brain regions and the anterior pituitary of male rats. As compared to the reference (/sup 14/C)inulin, the amount of radioactivity was higher after (/sup 3/H)Nle/sup 11/-SP injection (0.233 +- 0.039%, p < 0.001). Statistically significant differences could be found particularly in cortical and caudal areas as well as in the circumventricular organs studied. These observations do not refute the assumption that a low brain uptake of the labelled neuropeptide occurred due to an accumulation within structures of the blood-brain barrier and/or a penetration of the barrier system.

  4. Surplus Cost Potential as a Life Cycle Impact Indicator for Metal Extraction

    OpenAIRE

    Marisa D.M. Vieira; Thomas C. Ponsioen; Goedkoop, Mark J.; Huijbregts, Mark A J

    2016-01-01

    In the evaluation of product life cycles, methods to assess the increase in scarcity of resources are still under development. Indicators that can express the importance of an increase in scarcity of metals extracted include surplus ore produced, surplus energy required, and surplus costs in the mining and the milling stage. Particularly the quantification of surplus costs per unit of metal extracted as an indicator is still in an early stage of development. Here, we developed a method that q...

  5. Changes of biochemical indices in brain, liver tissue and serum in mice with Alzheimer disease after Chinese medicine treatment

    Institute of Scientific and Technical Information of China (English)

    Xiangyang Wang; Lili Zhang; Haode Huang; Qiang Qin; Guimei Luo; Chaogan Li; Shuqiu Zhang

    2007-01-01

    BACKGROUND: Alzheimer disease is a main type of dementia, and the important clinical characteristic is the rapid declines of memory and cognitive ability.OBJECTIVE: To study changes of biochemical indices in brain, liver tissue and serum, as well as memory of mice with Alzheimer disease after Chinese medicine treatment. DESIGN: A comparative animal experimental observation. SETTING: Haierfu Research Center of Youjiang Medical College for Nationalities.MATERIALS: Forty-eight healthy Kunming mice (24 males and 24 females), 3 months old, were provided by the animal room of Youjiang Medical College for Nationalities. The animals were divided into four groups according to sex and body mass: control group, model group, Wuyuan Buxue treated group, Haierfu treated group, and 12 mice in each group. Wuyuan Buxue oral liquid was extracted from Polygonum multiflorum Thunb (red, radix) and longan meat (country medicine quasi- word B20020828). Haierfu oral liquid was extracted from Yinhua, poriacocos, licorice, etc (Q/452600RYYLC01-92). METHODS: The experiment was completed in Haierfu Research Center and Institute of Heavy Metal and Fluorosis-Arsenism of Youjiang Medical College for Nationalities from May 2006 to December 2006. ①All animals except those in the control group were given feed which was mixed with AlC3 (12 g/L), and they could freely drink 3 g/L Al(NO3)3. The mice in the control group were given normal feed. Wuyuan Buxue oral liquid and Haierfu oral liquid were distilled by distilled water for one time respectively. Five months after model establishment, mice in the Wuyuan Buxue treated group and Haierfu treated group were given intrapastric perfusion of Wuyuan Buxue oral liquid and Haierfu oral liquid respectively, and those in the model group and control group were given intrapastric perfusion of distilled water of the same volume. All the mice were treated for 45 days. ②The swimming time (s) and error times were determined with Y-shape water maze before and

  6. Potential applications of image-guided radiotherapy for brain metastases and glioblastoma to improve patient quality of life

    Directory of Open Access Journals (Sweden)

    Nam Phong Nguyen

    2013-11-01

    Full Text Available Treatment of glioblastoma multiforme (GBM and brain metastasis remains a challenge because of the poor survival and the potential for brain damage following radiation. Despite concurrent chemotherapy and radiation dose escalation, local recurrence remains the predominant pattern of failure in GBM most likely secondary to repopulation of cancer stem cells. Even though radiotherapy is highly effective for local control of radio-resistant tumors such as melanoma and renal cell cancer, systemic disease progression is the cause of death in most patients with brain metastasis. Preservation of quality of life of cancer survivors is the main issue for patients with brain metastasis. Image-guided radiotherapy (IGRT by virtue of precise radiation dose delivery may reduce treatment time of patients with GBM without excessive toxicity and potentially improve neurocognitive function with preservation of local control in patients with brain metastasis. Future prospective trials for primary brain tumors or brain metastasis should include IGRT to assess its efficacy to improve patient quality of life.

  7. Oxidation-Reduction Potential as a Biomarker for Severity and Acute Outcome in Traumatic Brain Injury.

    Science.gov (United States)

    Bjugstad, Kimberly B; Rael, Leonard T; Levy, Stewart; Carrick, Matthew; Mains, Charles W; Slone, Denetta S; Bar-Or, David

    2016-01-01

    There are few reliable markers for assessing traumatic brain injury (TBI). Elevated levels of oxidative stress have been observed in TBI patients. We hypothesized that oxidation-reduction potential (ORP) could be a potent biomarker in TBI. Two types of ORP were measured in patient plasma samples: the static state of oxidative stress (sORP) and capacity for induced oxidative stress (icORP). Differences in ORP values as a function of time after injury, severity, and hospital discharge were compared using ANOVAs with significance at p ≤ 0.05. Logit regression analyses were used to predict acute outcome comparing ORP, Injury Severity Score (ISS), Abbreviated Injury Scale (AIS), and Glasgow Coma Scale (GCS). Antioxidant capacity (icORP) on day 4 was prognostic for acute outcomes (p 7.25 μC. IcORP was a better predictor than ISS, AIS, or GCS scores. sORP increased in those with the highest ISS values (p brain injury over time is a factor that determines outcome. PMID:27642494

  8. The Brain Drain Potential of Students in the African Health and Nonhealth Sectors

    Directory of Open Access Journals (Sweden)

    Jonathan Crush

    2012-01-01

    Full Text Available The departure of health professionals to Europe and North America is placing an intolerable burden on public health systems in many African countries. Various retention, recall, and replacement policies to ameliorate the impact of this brain drain have been suggested, none of which have been particularly successful to date. The key question for the future is whether the brain drain of health sector skills is likely to continue and whether the investment of African countries in training health professionals will continue to be lost through emigration. This paper examines the emigration intentions of trainee health professionals in six Southern African countries. The data was collected by the Southern African Migration Program (SAMP in a survey of final-year students across the region which included 651 students training for the health professions. The data also allows for the comparison of health sector with other students. The analysis presented in this paper shows very high emigration potential amongst all final-year students. Health sector students do show a slightly higher inclination to leave than those training to work in other sectors. These findings present a considerable challenge for policy makers seeking to encourage students to stay at home and work after graduation.

  9. Errare machinale est: The use of error-related potentials in brain-machine interfaces

    Directory of Open Access Journals (Sweden)

    Ricardo eChavarriaga

    2014-07-01

    Full Text Available The ability to recognize errors is crucial for efficient behavior. Numerous studies have identified electrophysiological correlates of error recognition in the human brain (error-related potentials, ErrPs. Consequently, it has been proposed to use these signals to improve human-computer interaction (HCI or brain-machine interfacing (BMI. Here, we present a review of over a decade of developments towards this goal. This body of work provides consistent evidence that ErrPs can be successfully detected on a single-trial basis, and that they can be effectively used in both HCI and BMI applications.We first describe the ErrP phenomenon and follow up with an analysis of different strategies to increase the robustness of a system by incorporating single-trial ErrP recognition, either by correcting the machine's actions or by providing means for its error-based adaptation. These approaches can be applied both when the user employs traditional HCI input devices or in combination with another BMI channel.Finally, we discuss the current challenges that have to be overcome in order to fully integrate ErrPs into practical applications. This includes, in particular, the characterization of such signals during real(istic applications, as well as the possibility of extracting richer information from them, going beyond the time-locked decoding that dominates current approaches.

  10. Potential contribution of aromatase inhibition to the effects of nicotine and related compounds on the brain.

    Science.gov (United States)

    Biegon, Anat; Alia-Klein, Nelly; Fowler, Joanna S

    2012-01-01

    Cigarette smoking continues to be a major public health problem, and while smoking rates in men have shown some decrease over the last few decades, smoking rates among girls and young women are increasing. Practically all of the important aspects of cigarette smoking and many effects of nicotine are sexually dimorphic (reviewed by Pogun and Yararbas, 2009). Women become addicted more easily than men, while finding it harder to quit. Nicotine replacement appears to be less effective in women. This may be linked to the observation that women are more sensitive than men to non-nicotine cues or ingredients in cigarettes. The reasons for these sex differences are mostly unknown. Several lines of evidence suggest that many of the reported sex differences related to cigarette smoking may stem from the inhibitory effects of nicotine and other tobacco alkaloids on estrogen synthesis via the enzyme aromatase (cyp19a gene product). Aromatase is the last enzyme in estrogen biosynthesis, catalyzing the conversion of androgens to estrogens. This review provides a summary of experimental evidence supporting brain aromatase as a potential mediator and/or modulator of nicotine actions in the brain, contributing to sex differences in smoking behavior. Additional research on the interaction between tobacco smoke, nicotine, and aromatase may help devise new, sex specific methods for prevention and treatment of smoking addiction.

  11. Potential contribution of aromatase inhibition to the effects of nicotine and related compounds on the brain

    Directory of Open Access Journals (Sweden)

    Anat eBiegon

    2012-11-01

    Full Text Available Cigarette smoking continues to be a major public health problem, and while smoking rates in men have shown some decrease over the last few decades, smoking rates among girls and young women are increasing. Practically all of the important aspects of cigarette smoking are sexually dimorphic. Women become addicted more easily than men, while finding it harder to quit. Nicotine replacement appears to be less effective in women. This may be linked to the observation that women are more sensitive than men to non-nicotine cues or ingredients in cigarettes. The reasons for these sex differences are mostly unknown. Several lines of evidence suggest that many of the reported sex differences related to cigarette smoking may stem from the inhibitory effects of nicotine and other tobacco alkaloids on estrogen synthesis via the enzyme aromatase (cyp19a gene product. Aromatase is the last enzyme in estrogen biosynthesis, catalyzing the conversion of androgens to estrogens. This review provides a summary of experimental evidence supporting brain aromatase as a potential mediator and/or modulator of nicotine actions in the brain, contributing to sex differences in smoking behavior. Additional research on the interaction between tobacco smoke, nicotine and aromatase may help devise new, sex specific methods for prevention and treatment of smoking addiction.

  12. Neuroimaging studies of bilingual expressive language representation in the brain: potential applications for magnetoencephalography

    Institute of Scientific and Technical Information of China (English)

    Elizabeth W.Pang

    2012-01-01

    Bilingualism is the ability to use two or more languages with equal or near equal fluency.How the brain,often seamlessly,selects,controls,and switches between languages is an enigma.Neuroimaging studies offer the unique opportunity to probe the mechanisms underlying bilingual brain function.Non-invasive methods,in particular,functional MRI (fMRI) and event-related potentials (ERPs),have allowed examination in healthy control populations.Whole-head magnetoencephalography (MEG),a relatively new addition to the cadre of neuroimaging tools,offers a combination of the high spatial resolution of fMRI with the high temporal resolution of ERPs.Thus far,MEG has been applied to the studies of bilingual receptive language,or bilingual language comprehension.MEG has not yet been applied to the study of bilingual language production as such studies have faced more challenges (see Salmelin,2007 for a review),and these have only recently been addressed.Here,we review the literature on MEG expressive language studies and point out a direction for the application of MEG to the study of bilingual language production.

  13. No impact of deep brain stimulation on fear-potentiated startle in obsessive-compulsive disorder.

    Science.gov (United States)

    Baas, Johanna M P; Klumpers, Floris; Mantione, Mariska H; Figee, Martijn; Vulink, Nienke C; Schuurman, P Richard; Mazaheri, Ali; Denys, Damiaan

    2014-01-01

    Deep brain stimulation (DBS) of the ventral internal capsule is effective in treating therapy refractory obsessive-compulsive disorder (OCD). Given the close proximity of the stimulation site to the stria terminalis (BNST), we hypothesized that the striking decrease in anxiety symptoms following DBS could be the result of the modulation of contextual anxiety. However, the effect of DBS in this region on contextual anxiety is as of yet unknown. Thus, the current study investigated the effect of DBS on contextual anxiety in an experimental threat of shock paradigm. Eight patients with DBS treatment for severe OCD were tested in a double-blind crossover design with randomly assigned 2-week periods of active and sham stimulation. DBS resulted in significant decrease of obsessive-compulsive symptoms, anxiety, and depression. However, even though the threat manipulation resulted in a clear context-potentiated startle effect, none of the parameters derived from the startle recordings was modulated by the DBS. This suggests that DBS in the ventral internal capsule is effective in treating anxiety symptoms of OCD without modulating the startle circuitry. We hypothesize that the anxiety symptoms present in OCD are likely distinct from the pathological brain circuits in defensive states of other anxiety disorders. PMID:25249953

  14. No Impact of Deep Brain Stimulation on Fear-Potentiated Startle in Obsessive–Compulsive Disorder

    Science.gov (United States)

    Baas, Johanna M. P.; Klumpers, Floris; Mantione, Mariska H.; Figee, Martijn; Vulink, Nienke C.; Schuurman, P. Richard; Mazaheri, Ali; Denys, Damiaan

    2014-01-01

    Deep brain stimulation (DBS) of the ventral internal capsule is effective in treating therapy refractory obsessive–compulsive disorder (OCD). Given the close proximity of the stimulation site to the stria terminalis (BNST), we hypothesized that the striking decrease in anxiety symptoms following DBS could be the result of the modulation of contextual anxiety. However, the effect of DBS in this region on contextual anxiety is as of yet unknown. Thus, the current study investigated the effect of DBS on contextual anxiety in an experimental threat of shock paradigm. Eight patients with DBS treatment for severe OCD were tested in a double-blind crossover design with randomly assigned 2-week periods of active and sham stimulation. DBS resulted in significant decrease of obsessive–compulsive symptoms, anxiety, and depression. However, even though the threat manipulation resulted in a clear context-potentiated startle effect, none of the parameters derived from the startle recordings was modulated by the DBS. This suggests that DBS in the ventral internal capsule is effective in treating anxiety symptoms of OCD without modulating the startle circuitry. We hypothesize that the anxiety symptoms present in OCD are likely distinct from the pathological brain circuits in defensive states of other anxiety disorders. PMID:25249953

  15. No impact of deep brain stimulation on fear-potentiated startle in obsessive-compulsive disorder

    Directory of Open Access Journals (Sweden)

    Johanna M.P. Baas

    2014-09-01

    Full Text Available Deep brain stimulation (DBS of the ventral internal capsule is effective in treating therapy refractory obsessive-compulsive disorder (OCD. Given the close proximity of the stimulation site to the stria terminalis (BNST, we hypothesized that the striking decrease in anxiety symptoms following DBS could be the result of the modulation of contextual anxiety. However, the effect of DBS in this region on contextual anxiety is as of yet unknown. Thus, the current study investigated the effect of DBS on contextual anxiety in an experimental threat of shock paradigm. Eight patients with DBS treatment for severe OCD were tested in a double-blind crossover design with randomly assigned two-week periods of active and sham stimulation. DBS resulted in significant decrease of obsessive-compulsive symptoms, anxiety and depression. However, even though the threat manipulation resulted in a clear context potentiated startle effect, none of the parameters derived from the startle recordings was modulated by the DBS. This suggests that DBS in the ventral internal capsule is effective in treating anxiety symptoms of obsessive-compulsive disorder without modulating the startle circuitry. We hypothesize that the anxiety symptoms present in OCD are likely distinct from the pathological brain circuits in defensive states of other anxiety disorders.

  16. Effects of PPP1R1B (DARPP-32 Polymorphism on Feedback-related Brain Potentials across the Life Span

    Directory of Open Access Journals (Sweden)

    Dorothea eHämmerer

    2013-03-01

    Full Text Available Maximizing gains during probabilistic reinforcement learning requires the updating of choice–outcome expectations at the time when the feedback about a specific choice or action is given. Extant theories and evidence suggest that dopaminergic modulation plays a crucial role in reinforcement learning and the updating of choice–outcome expectations. Furthermore, recently a positive component of the event-related potential (ERP about 200 msec (P2 after feedback has been suggested to reflect such updating. The efficacy of dopaminergic modulation changes across the life span. However, to date investigations of age-related differences in feedback-related P2 during reinforcement learning are still scarce. The present study thus aims to investigate whether individual differences in the feedback-related P2 would be associated with polymorphic variations in a dopamine relevant gene PPP1R1B (also known as DARPP-32 and whether the genetic effect may differ between age groups. We observed larger P2 amplitudes in individuals carrying the genotype associated with higher dopamine receptor efficacy, i.e., A allele homozygotes of a single nucleotide polymorphism (rs907094 of the PPP1R1B gene. Moreover, this effect was more pronounced in children and older adults in comparison to adolescents and younger adults. Together, our findings indicate that polymorphic variations in a dopamine relevant gene are associated with individual differences in brain-evoked potentials of outcome updating and hint at the possibility that genotype effects on neurocognitive phenotypes may vary as a function of brain maturation and aging.

  17. 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

  18. Indices of Impaired Self-Awareness in Traumatic Brain Injury Patients with Focal Frontal Lesions and Executive Deficits : Implications for Outcome Measurement

    NARCIS (Netherlands)

    Spikman, Jacoba M.; van der Naalt, Joukje

    2010-01-01

    In patients with moderate to severe traumatic brain injury (TBI), impairments of self-awareness are frequently found and associated with worse functional outcome and poor compliance with rehabilitation. The aim of this study was to investigate whether indications of impaired self-awareness could be

  19. Identifying Student Potential for ICT Entrepreneurship Using Myers-Briggs Personality Type Indicators

    Science.gov (United States)

    Johnston, Kevin A.; Andersen, Barry K.; Davidge-Pitts, Jennifer; Ostensen-Saunders, Mark

    2009-01-01

    Literature relating to personality and entrepreneurship has focused primarily on personality characteristics of traditional entrepreneurs. The focus of this study was on personality characteristics and temperaments of potential Information and Communication Technology (ICT) entrepreneurs. The main objective of the study was to evaluate the…

  20. Coupling of transient near infrared photonic with magnetic nanoparticle for potential dissipation-free biomedical application in brain

    Science.gov (United States)

    Sagar, Vidya; Atluri, V. S. R.; Tomitaka, A.; Shah, P.; Nagasetti, A.; Pilakka-Kanthikeel, S.; El-Hage, N.; McGoron, A.; Takemura, Y.; Nair, M.

    2016-07-01

    Combined treatment strategies based on magnetic nanoparticles (MNPs) with near infrared ray (NIR) biophotonic possess tremendous potential for non-invasive therapeutic approach. Nonetheless, investigations in this direction have been limited to peripheral body region and little is known about the potential biomedical application of this approach for brain. Here we report that transient NIR exposure is dissipation-free and has no adverse effect on the viability and plasticity of major brain cells in the presence or absence superparamagnetic nanoparticles. The 808 nm NIR laser module with thermocouple was employed for functional studies upon NIR exposure to brain cells. Magnetic nanoparticles were characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), dynamic laser scattering (DLS), and vibrating sample magnetometer (VSM). Brain cells viability and plasticity were analyzed using electric cell-substrate impedance sensing system, cytotoxicity evaluation, and confocal microscopy. When efficacious non-invasive photobiomodulation and neuro-therapeutical targeting and monitoring to brain remain a formidable task, the discovery of this dissipation-free, transient NIR photonic approach for brain cells possesses remarkable potential to add new dimension.

  1. Steady State Visual Evoked Potential Based Brain-Computer Interface for Cognitive Assessment

    DEFF Research Database (Denmark)

    Westergren, Nicolai; Bendtsen, Rasmus L.; Kjær, Troels W.;

    2016-01-01

    decline is important. Cognitive decline may be detected using fullyautomated computerized assessment. Such systems will provide inexpensive and widely available screenings of cognitive ability. The aim of this pilot study is to develop a real time steady state visual evoked potential (SSVEP) based brain-computer...... subjects achieved an information transfer rate (ITR) of 14:64 bits/min ± 7:63 bits=min and a subject test performance of 47:22% ± 34:10%. This study suggests that BCI may be applicable in practice as a computerized cognitive assessment tool. However, many improvements are required for the system...... interface (BCI) for neurological cognitive assessment. It is intended for use by patients who suffer from diseases impairing their motor skills, but are still able to control their gaze. Results are based on 11 healthy test subjects. The system performance have an average accuracy of 100% ± 0%. The test...

  2. Parallel synthesis of a series of potentially brain penetrant aminoalkyl benzoimidazoles.

    Science.gov (United States)

    Micco, Iolanda; Nencini, Arianna; Quinn, Joanna; Bothmann, Hendrick; Ghiron, Chiara; Padova, Alessandro; Papini, Silvia

    2008-03-01

    Alpha7 agonists were identified via GOLD (CCDC) docking in the putative agonist binding site of an alpha7 homology model and a series of aminoalkyl benzoimidazoles was synthesised to obtain potentially brain penetrant drugs. The array was prepared starting from the reaction of ortho-fluoronitrobenzenes with a selection of diamines, followed by reduction of the nitro group to obtain a series of monoalkylated phenylene diamines. N,N'-Carbonyldiimidazole (CDI) mediated acylation, followed by a parallel automated work-up procedure, afforded the monoacylated phenylenediamines which were cyclised under acidic conditions. Parallel work-up and purification afforded the array products in good yields and purities with a robust parallel methodology which will be useful for other libraries. Screening for alpha7 activity revealed compounds with agonist activity for the receptor.

  3. The maternal brain under stress: Consequences for adaptive peripartum plasticity and its potential functional implications.

    Science.gov (United States)

    Slattery, David A; Hillerer, Katharina M

    2016-04-01

    The peripartum period represents a time during which all mammalian species undergo substantial physiological and behavioural changes, which prepare the female for the demands of motherhood. In addition to behavioural and physiological alterations, numerous brain regions, such as the medial prefrontal cortex, olfactory bulb, medial amygdala and hippocampus are subject to substantial peripartum-associated neuronal, dendritic and synaptic plasticity. These changes, which are temporally- and spatially-distinct, are strongly influenced by gonadal and adrenal hormones, such as estrogen and cortisol/corticosterone, which undergo dramatic fluctuations across this period. In this review, we describe our current knowledge regarding these plasticity changes and describe how stress affects such normal adaptations. Finally, we discuss the mechanisms potentially underlying these neuronal, dendritic and synaptic changes and their functional relevance for the mother and her offspring. PMID:26828151

  4. The cognitive demands of second order manual control: Applications of the event related brain potential

    Science.gov (United States)

    Wickens, C.; Gill, R.; Kramer, A.; Ross, W.; Donchin, E.

    1981-01-01

    Three experiments are described in which tracking difficulty is varied in the presence of a covert tone discrimination task. Event related brain potentials (ERPs) elicited by the tones are employed as an index of the resource demands of tracking. The ERP measure reflected the control order variation, and this variable was thereby assumed to compete for perceptual/central processing resources. A fine-grained analysis of the results suggested that the primary demands of second order tracking involve the central processing operations of maintaining a more complex internal model of the dynamic system, rather than the perceptual demands of higher derivative perception. Experiment 3 varied tracking bandwidth in random input tracking, and the ERP was unaffected. Bandwidth was then inferred to compete for response-related processing resources that are independent of the ERP.

  5. Brain potentials in patients with music perception deficits: evidence for an early locus.

    Science.gov (United States)

    Münte, T F; Schuppert, M; Johannes, S; Wieringa, B M; Kohlmetz, C; Altenmüller, E

    1998-11-01

    Twelve patients with an acute cerebrovascular accident were assigned to a group with music perception deficits (amusia, n = 6) or a group without such deficits (n = 6) on the basis of a new test-battery for music-perception skills. Event-related brain potentials (ERPs) were recorded in an auditory classification task designed to elicit several components; the N1 as a correlate of initial auditory cortical processing, the P3a as an index of automatic attentional orienting, and the P3b as a measure for controlled stimulus evaluation. Patients with amusia showed a significant amplitude decrement for the P3a relative to controls and patients without amusia suggesting an impairment of early stimulus evaluation. P3b was reduced in both patient groups relative to control. These data show that amusia is quite common in unselected stroke patients and suggest deficits of generic rather than music-specific cognitive processes as the underlying cause. PMID:9853709

  6. Parallel synthesis of a series of potentially brain penetrant aminoalkyl benzoimidazoles.

    Science.gov (United States)

    Micco, Iolanda; Nencini, Arianna; Quinn, Joanna; Bothmann, Hendrick; Ghiron, Chiara; Padova, Alessandro; Papini, Silvia

    2008-03-01

    Alpha7 agonists were identified via GOLD (CCDC) docking in the putative agonist binding site of an alpha7 homology model and a series of aminoalkyl benzoimidazoles was synthesised to obtain potentially brain penetrant drugs. The array was prepared starting from the reaction of ortho-fluoronitrobenzenes with a selection of diamines, followed by reduction of the nitro group to obtain a series of monoalkylated phenylene diamines. N,N'-Carbonyldiimidazole (CDI) mediated acylation, followed by a parallel automated work-up procedure, afforded the monoacylated phenylenediamines which were cyclised under acidic conditions. Parallel work-up and purification afforded the array products in good yields and purities with a robust parallel methodology which will be useful for other libraries. Screening for alpha7 activity revealed compounds with agonist activity for the receptor. PMID:18078760

  7. Hydrologic indicators of hot spots and hot moments of mercury methylation potential along river corridors.

    Science.gov (United States)

    Singer, Michael Bliss; Harrison, Lee R; Donovan, Patrick M; Blum, Joel D; Marvin-DiPasquale, Mark

    2016-10-15

    The biogeochemical cycling of metals and other contaminants in river-floodplain corridors is controlled by microbial activity responding to dynamic redox conditions. Riverine flooding thus has the potential to affect speciation of redox-sensitive metals such as mercury (Hg). Therefore, inundation history over a period of decades potentially holds information on past production of bioavailable Hg. We investigate this within a Northern California river system with a legacy of landscape-scale 19th century hydraulic gold mining. We combine hydraulic modeling, Hg measurements in sediment and biota, and first-order calculations of mercury transformation to assess the potential role of river floodplains in producing monomethylmercury (MMHg), a neurotoxin which accumulates in local and migratory food webs. We identify frequently inundated floodplain areas, as well as floodplain areas inundated for long periods. We quantify the probability of MMHg production potential (MPP) associated with hydrology in each sector of the river system as a function of the spatial patterns of overbank inundation and drainage, which affect long-term redox history of contaminated sediments. Our findings identify river floodplains as periodic, temporary, yet potentially important, loci of biogeochemical transformation in which contaminants may undergo change during limited periods of the hydrologic record. We suggest that inundation is an important driver of MPP in river corridors and that the entire flow history must be analyzed retrospectively in terms of inundation magnitude and frequency in order to accurately assess biogeochemical risks, rather than merely highlighting the largest floods or low-flow periods. MMHg bioaccumulation within the aquatic food web in this system may pose a major risk to humans and waterfowl that eat migratory salmonids, which are being encouraged to come up these rivers to spawn. There is a long-term pattern of MPP under the current flow regime that is likely to be

  8. Hydrologic indicators of hot spots and hot moments of mercury methylation potential along river corridors

    Science.gov (United States)

    Singer, Michael B.; Harrison, Lee R.; Donovan, Patrick M.; Blum, Joel D.; Marvin-DiPasquale, Mark C.

    2016-01-01

    The biogeochemical cycling of metals and other contaminants in river-floodplain corridors is controlled by microbial activity responding to dynamic redox conditions. Riverine flooding thus has the potential to affect speciation of redox-sensitive metals such as mercury (Hg). Therefore, inundation history over a period of decades potentially holds information on past production of bioavailable Hg. We investigate this within a Northern California river system with a legacy of landscape-scale 19th century hydraulic gold mining. We combine hydraulic modeling, Hg measurements in sediment and biota, and first-order calculations of mercury transformation to assess the potential role of river floodplains in producing monomethylmercury (MMHg), a neurotoxin which accumulates in local and migratory food webs. We identify frequently inundated floodplain areas, as well as floodplain areas inundated for long periods. We quantify the probability of MMHg production potential (MPP) associated with hydrology in each sector of the river system as a function of the spatial patterns of overbank inundation and drainage, which affect long-term redox history of contaminated sediments. Our findings identify river floodplains as periodic, temporary, yet potentially important, loci of biogeochemical transformation in which contaminants may undergo change during limited periods of the hydrologic record. We suggest that inundation is an important driver of MPP in river corridors and that the entire flow history must be analyzed retrospectively in terms of inundation magnitude and frequency in order to accurately assess biogeochemical risks, rather than merely highlighting the largest floods or low-flow periods. MMHg bioaccumulation within the aquatic food web in this system may pose a major risk to humans and waterfowl that eat migratory salmonids, which are being encouraged to come up these rivers to spawn. There is a long-term pattern of MPP under the current flow regime that is likely to be

  9. Potential additional indicators for pacemaker requirement in isolated congenital atrioventricular block.

    NARCIS (Netherlands)

    Breur, J.M.; Udink ten Cate, F.E.; Kapusta, L.; Boramanand, N.; Cohen, M.I.; Crosson, J.E.; Lubbers, L.J.; Friedman, A.H.; Brenner, J.I.; Vetter, V.L.; Meijboom, E.J.

    2006-01-01

    Low heart rate is the predominantly used indication for pacemaker intervention in patients with isolated congenital atrioventricular block (CAVB). The aim of this study was to compare the difference in heart rates recorded with ECG and Holter monitoring between paced (PM) and nonpaced (NPM) patients

  10. Potential additional indicators for pacemaker requirement in isolated congenital atrioventricular block

    NARCIS (Netherlands)

    J.M.P.J. Breur; F.E.A.U. ten Cate; L. Kapusta; N. Boramanand; M.I. Cohen; J.E. Crosson; L.J. Lubbers; A.H. Friedman; J.I. Brenner; V.L. Vetter; E.J. Meijboom

    2006-01-01

    Low heart rate is the predominantly used indication for pacemaker intervention in patients with isolated congenital atrioventricular block (CAVB). The aim of this study was to compare the difference in heart rates recorded with ECG and Holter monitoring between paced (PM) and nonpaced (NPM) patients

  11. On the Potential of Surfers to Monitor Environmental Indicators in the Coastal Zone.

    Directory of Open Access Journals (Sweden)

    Robert J W Brewin

    Full Text Available The social and economic benefits of the coastal zone make it one of the most treasured environments on our planet. Yet it is vulnerable to increasing anthropogenic pressure and climate change. Coastal management aims to mitigate these pressures while augmenting the socio-economic benefits the coastal region has to offer. However, coastal management is challenged by inadequate sampling of key environmental indicators, partly due to issues relating to cost of data collection. Here, we investigate the use of recreational surfers as platforms to improve sampling coverage of environmental indicators in the coastal zone. We equipped a recreational surfer, based in the south west United Kingdom (UK, with a temperature sensor and Global Positioning System (GPS device that they used when surfing for a period of one year (85 surfing sessions. The temperature sensor was used to derive estimates of sea-surface temperature (SST, an important environmental indicator, and the GPS device used to provide sample location and to extract information on surfer performance. SST data acquired by the surfer were compared with data from an oceanographic station in the south west UK and with satellite observations. Our results demonstrate: (i high-quality SST data can be acquired by surfers using low cost sensors; and (ii GPS data can provide information on surfing performance that may help motivate data collection by surfers. Using recent estimates of the UK surfing population, and frequency of surfer participation, we speculate around 40 million measurements on environmental indicators per year could be acquired at the UK coastline by surfers. This quantity of data is likely to enhance coastal monitoring and aid UK coastal management. Considering surfing is a world-wide sport, our results have global implications and the approach could be expanded to other popular marine recreational activities for coastal monitoring of environmental indicators.

  12. A risk modelling approach for setting microbiological limits using enterococci as indicator for growth potential of Salmonella in pork

    DEFF Research Database (Denmark)

    Bollerslev, Anne Mette; Nauta, Maarten; Hansen, Tina Beck;

    2016-01-01

    hygiene interventions. The objective of the present study was to develop an approach which could make it possible to define potential risk-based microbiological limits for an indicator, enterococci, in order to evaluate the risk from potential growth of Salmonella. A positive correlation between...... products that has enterococci concentrations above 5. log. CFU/g. This illustrates that our approach can be used to evaluate the potential effect of different microbiological limits and therefore, the perspective of this novel approach is that it can be used for definition of a risk-based microbiological...... are carried in the intestinal tract, contaminate pork by the same mechanisms and share similar growth characteristics (lag phase and maximum specific growth rate) at temperatures around 5-10. °C, suggest a potential of enterococci to be used as an indicator of potential growth of Salmonella in pork. Elevated...

  13. The impact of hunger on food cue processing: an event-related brain potential study.

    Science.gov (United States)

    Stockburger, Jessica; Schmälzle, Ralf; Flaisch, Tobias; Bublatzky, Florian; Schupp, Harald T

    2009-10-01

    The present study used event-related brain potentials to examine deprivation effects on visual attention to food stimuli at the level of distinct processing stages. Thirty-two healthy volunteers (16 females) were tested twice 1 week apart, either after 24 h of food deprivation or after normal food intake. Participants viewed a continuous stream of food and flower images while dense sensor ERPs were recorded. As revealed by distinct ERP modulations in relatively earlier and later time windows, deprivation affected the processing of food and flower pictures. Between 300 and 360 ms, food pictures were associated with enlarged occipito-temporal negativity and centro-parietal positivity in deprived compared to satiated state. Of main interest, in a later time window (approximately 450-600 ms), deprivation increased amplitudes of the late positive potential elicited by food pictures. Conversely, flower processing varied by motivational state with decreased positive potentials in the deprived state. Minimum-Norm analyses provided further evidence that deprivation enhanced visual attention to food cues in later processing stages. From the perspective of motivated attention, hunger may induce a heightened state of attention for food stimuli in a processing stage related to stimulus recognition and focused attention.

  14. Potential Lung Nodules Identification for Characterization by Variable Multistep Threshold and Shape Indices from CT Images

    OpenAIRE

    Saleem Iqbal; Khalid Iqbal; Fahim Arif; Arslan Shaukat; Aasia Khanum

    2014-01-01

    Computed tomography (CT) is an important imaging modality. Physicians, surgeons, and oncologists prefer CT scan for diagnosis of lung cancer. However, some nodules are missed in CT scan. Computer aided diagnosis methods are useful for radiologists for detection of these nodules and early diagnosis of lung cancer. Early detection of malignant nodule is helpful for treatment. Computer aided diagnosis of lung cancer involves lung segmentation, potential nodules identification, features extractio...

  15. Bivalves as indicators of environmental variation and potential anthropogenic impacts in the southern Barents Sea

    OpenAIRE

    Carroll, Michael L.; Johnson, Beverly J.; Henkes, Gregory A.; McMahon, Kelton W.; Voronkov, Andrey; Ambrose, William G.; Denisenko, Stanislav G.

    2009-01-01

    Identifying patterns and drivers of natural variability in populations is necessary to gauge potential effects of climatic change and the expected increases in commercial activities in the Arctic on communities and ecosystems. We analyzed growth rates and shell geochemistry of the circumpolar Greenland smooth cockle, Serripes groenlandicus, from the southern Barents Sea over almost 70 years between 1882 and 1968. The datasets were calibrated via annually-deposited growth lines, and growth, st...

  16. Representations in human visual short-term memory : an event-related brain potential study

    NARCIS (Netherlands)

    Klaver, P; Smid, HGOM; Heinze, HJ

    1999-01-01

    Behavioral measures and event-related potentials (ERPs) were recorded from 12 subjects while performing three delayed matching-to-sample tasks. The task instructions indicated whether stimulus locations, shapes or conjunctions of locations and shapes had to be memorized and matched against a probe.

  17. Metagenomic Analysis Indicates Epsilonproteobacteria as a Potential Cause of Microbial Corrosion in Pipelines Injected with Bisulfite

    OpenAIRE

    An, Dongshan; Dong, Xiaoli; An, Annie; Park, Hyung S.; Strous, Marc; Voordouw, Gerrit

    2016-01-01

    Sodium bisulfite (SBS) is used as an oxygen scavenger to decrease corrosion in pipelines transporting brackish subsurface water used in the production of bitumen by steam-assisted gravity drainage. Sequencing 16S rRNA gene amplicons has indicated that SBS addition increased the fraction of the sulfate-reducing bacteria (SRB) Desulfomicrobium, as well as of Desulfocapsa, which can also grow by disproportionating sulfite into sulfide, sulfur, and sulfate. SRB use cathodic H2, formed by reductio...

  18. Using a biological indicator to detect potential sources of cross-contamination in the dental operatory.

    Science.gov (United States)

    Hackney, R W; Crawford, J J; Tulis, J J

    1998-11-01

    The authors conducted a study using surveillance monitoring methodology to identify operatory contamination and to evaluate the effectiveness of infection control procedures. Viridans streptococci were evaluated as biological indicators of oral contamination. Viridans streptococci, abundant in human saliva, were detected on operatory surfaces after dental treatments were finished and surfaces were disinfected. The findings validate current concepts of infection control as demonstrated in barrier methods.

  19. Auditory evoked potentials to spectro-temporal modulation of complex tones in normal subjects and patients with severe brain injury.

    Science.gov (United States)

    Jones, S J; Vaz Pato, M; Sprague, L; Stokes, M; Munday, R; Haque, N

    2000-05-01

    In order to assess higher auditory processing capabilities, long-latency auditory evoked potentials (AEPs) were recorded to synthesized musical instrument tones in 22 post-comatose patients with severe brain injury causing variably attenuated behavioural responsiveness. On the basis of normative studies, three different types of spectro-temporal modulation were employed. When a continuous 'clarinet' tone changes pitch once every few seconds, N1/P2 potentials are evoked at latencies of approximately 90 and 180 ms, respectively. Their distribution in the fronto-central region is consistent with generators in the supratemporal cortex of both hemispheres. When the pitch is modulated at a much faster rate ( approximately 16 changes/s), responses to each change are virtually abolished but potentials with similar distribution are still elicited by changing the timbre (e.g. 'clarinet' to 'oboe') every few seconds. These responses appear to represent the cortical processes concerned with spectral pattern analysis and the grouping of frequency components to form sound 'objects'. Following a period of 16/s oscillation between two pitches, a more anteriorly distributed negativity is evoked on resumption of a steady pitch. Various lines of evidence suggest that this is probably equivalent to the 'mismatch negativity' (MMN), reflecting a pre-perceptual, memory-based process for detection of change in spectro-temporal sound patterns. This method requires no off-line subtraction of AEPs evoked by the onset of a tone, and the MMN is produced rapidly and robustly with considerably larger amplitude (usually >5 microV) than that to discontinuous pure tones. In the brain-injured patients, the presence of AEPs to two or more complex tone stimuli (in the combined assessment of two authors who were 'blind' to the clinical and behavioural data) was significantly associated with the demonstrable possession of discriminative hearing (the ability to respond differentially to verbal commands

  20. Agent based modeling of the effects of potential treatments over the blood-brain barrier in multiple sclerosis.

    Science.gov (United States)

    Pennisi, Marzio; Russo, Giulia; Motta, Santo; Pappalardo, Francesco

    2015-12-01

    Multiple sclerosis is a disease of the central nervous system that involves the destruction of the insulating sheath of axons, causing severe disabilities. Since the etiology of the disease is not yet fully understood, the use of novel techniques that may help to understand the disease, to suggest potential therapies and to test the effects of candidate treatments is highly advisable. To this end we developed an agent based model that demonstrated its ability to reproduce the typical oscillatory behavior observed in the most common form of multiple sclerosis, relapsing-remitting multiple sclerosis. The model has then been used to test the potential beneficial effects of vitamin D over the disease. Many scientific studies underlined the importance of the blood-brain barrier and of the mechanisms that influence its permeability on the development of the disease. In the present paper we further extend our previously developed model with a mechanism that mimics the blood-brain barrier behavior. The goal of our work is to suggest the best strategies to follow for developing new potential treatments that intervene in the blood-brain barrier. Results suggest that the best treatments should potentially prevent the opening of the blood-brain barrier, as treatments that help in recovering the blood-brain barrier functionality could be less effective. PMID:26343337

  1. Fault locking near Istanbul: indication of earthquake potential from InSAR and GPS observations

    Science.gov (United States)

    Diao, Faqi; Walter, Thomas R.; Solaro, Giuseppe; Wang, Rongjiang; Bonano, Manuela; Manzo, Mariarosaria; Ergintav, Semih; Zheng, Yong; Xiong, Xiong; Lanari, Riccardo

    2016-04-01

    A sequence of large earthquakes occurred along the North Anatolian fault in the 20th century. These earthquakes, including the 1999 İzmit/Düzce earthquakes, generally propagated westward towards the Marmara Sea, defining the Main Marmara fault as a potential seismic gap. It is important to conduct a detailed assessment of the seismic hazards along the main Marmara fault because the megacity Istanbul lies only approximately 10 km north of the eastern segment of the Main Marmara fault, which is referred to as the Princes' Islands Fault segment (PIF). Here, we study the locking status of this fault segment to evaluate the seismic hazard potential. For the first time, combined ascending and descending Interferometric Synthetic Aperture Radar and Global Positioning System observations were used to investigate the crustal deformation associated with the PIF. After careful corrections of the estimated ground velocity, a deformation pattern relating to fault locking near the Princes' Islands was identified. The modeling results revealed that the slip rate and locking depth of the fault segment show a clear trade-off, which were estimated as 18.9 ± 7.2 mm yr-1 and 12.1 ± 7.0 km, respectively. With a moment accumulation rate of 1.7 ± 0.4 × 1017 Nm yr-1 (proportional to the product of slip rate and locking depth), our results imply a build-up of a geodetic moment on the PIF and therefore a potential for earthquake hazards in the vicinity of the Istanbul megacity.

  2. Flood basalt hosted palaeosols:Potential palaeoclimatic indicators of global climate change

    Institute of Scientific and Technical Information of China (English)

    M.R.G. Sayyed

    2014-01-01

    Since continental sediments (in addition to the marine geological record) offer important means of deciphering environmental changes, the sediments hosted by the successive flows of the continental flood basalt provinces of the world should be treasure houses in gathering the palaeoclimatic data. Palaeosols developed on top of basalt flows are potentially ideal for palaeoenvironmental reconstructions because it is easy to determine their protolith geochemistry and also they define a definite time interval. The present paper summarizes the nature of the basalt-hosted palaeosols formed on the flood basalts provinces from different parts of the globe having different ages.

  3. THE METHODOLOGY OF DEVELOPING VALUE INDICATORS TO INTEGRALLY ASSESS RESOURCE POTENTIAL IN AGRICULTURAL UNITS

    Directory of Open Access Journals (Sweden)

    Elena TIMOFTI

    2014-06-01

    Full Text Available The problem of increasing the economic efficiency of resource use in agricultural production is very important. Its solution directly depends on the economic security of the country and its constant supply with agricultural products.There are three basic factors in agricultural production: nature (land, labour and capital, which have differentmeasure units. Comparability is necessary to express the value of the integral potential that gives the possibility totake into account the main resources involved in producing and obtaining results from the agricultural sector.

  4. Postoperative Stereotactic Radiosurgery Without Whole-Brain Radiation Therapy for Brain Metastases: Potential Role of Preoperative Tumor Size

    Energy Technology Data Exchange (ETDEWEB)

    Hartford, Alan C., E-mail: Alan.C.Hartford@Hitchcock.org [Section of Radiation Oncology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Paravati, Anthony J. [Section of Radiation Oncology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Spire, William J. [Section of Neurosurgery, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Li, Zhongze [Biostatistics Shared Resource, Norris Cotton Cancer Center, Lebanon, New Hampshire (United States); Jarvis, Lesley A. [Section of Radiation Oncology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Fadul, Camilo E. [Section of Hematology/Oncology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Rhodes, C. Harker [Department of Pathology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Erkmen, Kadir [Section of Neurosurgery, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Friedman, Jonathan [Department of Surgery, Texas A and M College of Medicine, College Station, Texas (United States); Gladstone, David J. [Section of Radiation Oncology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Hug, Eugen B. [ProCure, New York, New York (United States); Roberts, David W.; Simmons, Nathan E. [Section of Neurosurgery, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States)

    2013-03-01

    Purpose: Radiation therapy following resection of a brain metastasis increases the probability of disease control at the surgical site. We analyzed our experience with postoperative stereotactic radiosurgery (SRS) as an alternative to whole-brain radiotherapy (WBRT), with an emphasis on identifying factors that might predict intracranial disease control and overall survival (OS). Methods and Materials: We retrospectively reviewed all patients through December 2008, who, after surgical resection, underwent SRS to the tumor bed, deferring WBRT. Multiple factors were analyzed for time to intracranial recurrence (ICR), whether local recurrence (LR) at the surgical bed or “distant” recurrence (DR) in the brain, for time to WBRT, and for OS. Results: A total of 49 lesions in 47 patients were treated with postoperative SRS. With median follow-up of 9.3 months (range, 1.1-61.4 months), local control rates at the resection cavity were 85.5% at 1 year and 66.9% at 2 years. OS rates at 1 and 2 years were 52.5% and 31.7%, respectively. On univariate analysis (preoperative) tumors larger than 3.0 cm exhibited a significantly shorter time to LR. At a cutoff of 2.0 cm, larger tumors resulted in significantly shorter times not only for LR but also for DR, ICR, and salvage WBRT. While multivariate Cox regressions showed preoperative size to be significant for times to DR, ICR, and WBRT, in similar multivariate analysis for OS, only the graded prognostic assessment proved to be significant. However, the number of intracranial metastases at presentation was not significantly associated with OS nor with other outcome variables. Conclusions: Larger tumor size was associated with shorter time to recurrence and with shorter time to salvage WBRT; however, larger tumors were not associated with decrements in OS, suggesting successful salvage. SRS to the tumor bed without WBRT is an effective treatment for resected brain metastases, achieving local control particularly for tumors up to

  5. Mid-infrared prediction of lactoferrin content in bovine milk: potential indicator of mastitis.

    Science.gov (United States)

    Soyeurt, H; Bastin, C; Colinet, F G; Arnould, V M-R; Berry, D P; Wall, E; Dehareng, F; Nguyen, H N; Dardenne, P; Schefers, J; Vandenplas, J; Weigel, K; Coffey, M; Théron, L; Detilleux, J; Reding, E; Gengler, N; McParland, S

    2012-11-01

    Lactoferrin (LTF) is a milk glycoprotein favorably associated with the immune system of dairy cows. Somatic cell count is often used as an indicator of mastitis in dairy cows, but knowledge on the milk LTF content could aid in mastitis detection. An inexpensive, rapid and robust method to predict milk LTF is required. The aim of this study was to develop an equation to quantify the LTF content in bovine milk using mid-infrared (MIR) spectrometry. LTF was quantified by enzyme-linked immunosorbent assay (ELISA), and all milk samples were analyzed by MIR. After discarding samples with a coefficient of variation between 2 ELISA measurements of more than 5% and the spectral outliers, the calibration set consisted of 2499 samples from Belgium (n = 110), Ireland (n = 1658) and Scotland (n = 731). Six statistical methods were evaluated to develop the LTF equation. The best method yielded a cross-validation coefficient of determination for LTF of 0.71 and a cross-validation standard error of 50.55 mg/l of milk. An external validation was undertaken using an additional dataset containing 274 Walloon samples. The validation coefficient of determination was 0.60. To assess the usefulness of the MIR predicted LTF, four logistic regressions using somatic cell score (SCS) and MIR LTF were developed to predict the presence of mastitis. The dataset used to build the logistic regressions consisted of 275 mastitis records and 13 507 MIR data collected in 18 Walloon herds. The LTF and the interaction SCS × LTF effects were significant (P test. In conclusion, this study confirms the possibility to quantify an LTF indicator from milk MIR spectra. It suggests the usefulness of this indicator associated to SCS to detect the presence of mastitis. Moreover, the knowledge of milk LTF could also improve the milk nutritional quality.

  6. Influence of drug transporters and stereoselectivity on the brain penetration of pioglitazone as a potential medicine against Alzheimer's disease.

    Science.gov (United States)

    Chang, Kai Lun; Pee, Hai Ning; Yang, Shili; Ho, Paul C

    2015-03-11

    Pioglitazone is currently undergoing clinical trials for treatment of Alzheimer's disease (AD). However, poor brain penetration remains an obstacle to development of the drug for such intended clinical uses. In this study, we demonstrate that the inhibition of P-glycoprotein (P-gp) significantly increases brain penetration of pioglitazone, whereas inhibition of breast cancer resistance protein (BCRP) has little effect. We also investigate the stereoselectivity of pioglitazone uptake in the brain. When mice were dosed with racemic pioglitazone, the concentration of (+)-pioglitazone was 46.6% higher than that of (-)-pioglitazone in brain tissue and 67.7% lower than that of (-)-pioglitazone in plasma. Dosing mice with pure (+)-pioglitazone led to a 76% increase in brain exposure levels compared to those from an equivalent dose of racemic pioglitazone. Pure (+)-pioglitazone was also shown to have comparable amyloid-lowering capabilities to the racemic pioglitazone in an in vitro AD model. These results suggest that P-gp may act as a stereoselective barrier to prevent pioglitazone entry into the brain. Dosing with (+)-pioglitazone instead of the racemic mixture may result in higher levels of brain exposure to pioglitazone, thus potentially improving the development of pioglitazone treatment of AD.

  7. Tradescantia micronucleus test indicates genotoxic potential of traffic emissions in European cities

    International Nuclear Information System (INIS)

    Urban atmospheres contain complex mixtures of air pollutants including mutagenic and carcinogenic substances such as benzene, diesel soot, heavy metals and polycyclic aromatic hydrocarbons. In the frame of a European network for the assessment of air quality by the use of bioindicator plants, the Tradescantia micronucleus (Trad-MCN) test was applied to examine the genotoxicity of urban air pollution. Cuttings of Tradescantia clone no. 4430 were exposed to ambient air at 65 monitoring sites in 10 conurbations employing a standardised methodology. The tests revealed an elevated genotoxic potential mainly at those urban sites which were exposed to severe car traffic emissions. This bioassay proved to be a suitable tool to detect local 'hot spots' of mutagenic air pollution in urban areas. For its use in routine monitoring programmes, however, further standardisation of cultivation and exposure techniques is recommended in order to reduce the variability of results due to varying environmental conditions. - The Tradescantia micronucleus test can be used to assess genotoxic potential at urban sites

  8. Self Potential as an indicator of biogeochemical transformations during active hydrocarbon biodegradation processes

    Science.gov (United States)

    Ntarlagiannis, D.; Heenan, J. W.; Slater, L. D.; Atekwana, E. A.; Rossbach, S.; Beaver, C. L.; Revil, A.; Bekins, B. A.

    2015-12-01

    Self potential (SP) signals, collected from borehole installation at the National Crude Oil Spill Fate and Natural Attenuation Research Site at Bemidji (MN), show a strong bipolar anomaly centered around the smear zone where intense bioremediation is known to occur. Magnetic susceptibility (MS) and geochemical analysis of soil cores confirmed the presence of a magnetite layer at the smear zone. The observed anomaly is consistent with the operation of a bio-geobattery centered on the conductive magnetite. This bio-geobattery is not permanent, but instead periodically shuts down, while at other times it reaches a maximum potential difference of ~ 70mV. The transient operation of the bio-geobattery appears to be associated with changes in the gradient of the redox species in the vicinity of the magnetite layer. Microbiological analysis of the soil cores identified microbial species that can support the operation of a bio-geobattery with the anode located below the magnetite, and the cathode above the magnetite layer. Environmental conditions local to the smear zone (e.g. water table change, rain water infiltration) seem to change the microbial dynamics around the magnetite layer resulting in redox gradient changes, essentially turning 'on' and 'off' the bio-geobattery. This work provides strong field-scale evidence for the functioning of a biogeobattery resulting from long-term biodegradation of a crude oil spill.

  9. Potential Lung Nodules Identification for Characterization by Variable Multistep Threshold and Shape Indices from CT Images

    Directory of Open Access Journals (Sweden)

    Saleem Iqbal

    2014-01-01

    Full Text Available Computed tomography (CT is an important imaging modality. Physicians, surgeons, and oncologists prefer CT scan for diagnosis of lung cancer. However, some nodules are missed in CT scan. Computer aided diagnosis methods are useful for radiologists for detection of these nodules and early diagnosis of lung cancer. Early detection of malignant nodule is helpful for treatment. Computer aided diagnosis of lung cancer involves lung segmentation, potential nodules identification, features extraction from the potential nodules, and classification of the nodules. In this paper, we are presenting an automatic method for detection and segmentation of lung nodules from CT scan for subsequent features extraction and classification. Contribution of the work is the detection and segmentation of small sized nodules, low and high contrast nodules, nodules attached with vasculature, nodules attached to pleura membrane, and nodules in close vicinity of the diaphragm and lung wall in one-go. The particular techniques of the method are multistep threshold for the nodule detection and shape index threshold for false positive reduction. We used 60 CT scans of “Lung Image Database Consortium-Image Database Resource Initiative” taken by GE medical systems LightSpeed16 scanner as dataset and correctly detected 92% nodules. The results are reproducible.

  10. Reduced habituation of auditory evoked potentials indicate cortical hyper-excitability in Fragile X Syndrome.

    Science.gov (United States)

    Ethridge, L E; White, S P; Mosconi, M W; Wang, J; Byerly, M J; Sweeney, J A

    2016-01-01

    Sensory hypersensitivities are common, clinically distressing features of Fragile X Syndrome (FXS). Preclinical evidence suggests this abnormality may result from synaptic hyper-excitability in sensory systems. This model predicts reduced sensory habituation to repeated stimulus presentation. Fourteen adolescents and adults with FXS and 15 age-matched controls participated in a modified auditory gating task using trains of 4 identical tones during dense array electroencephalography (EEG). Event-related potential and single trial time-frequency analyses revealed decreased habituation of the N1 event-related potential response in FXS, and increased gamma power coupled with decreases in gamma phase-locking during the early-stimulus registration period. EEG abnormalities in FXS were associated with parent reports of heightened sensory sensitivities and social communication deficits. Reduced habituation and altered gamma power and phase-locking to auditory cues demonstrated here in FXS patients parallels preclinical findings with Fmr1 KO mice. Thus, the EEG abnormalities seen in FXS patients support the model of neocortical hyper-excitability in FXS, and may provide useful translational biomarkers for evaluating novel treatment strategies targeting its neural substrate. PMID:27093069

  11. Sedimentary ladderane core lipids as potential indicators of hypoxia in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    ZHAO Zongshan; CAO Yali; LI Li; SONG Guodong; YANG Hongmei; LIU Sumei; ZHAO Meixun

    2013-01-01

    Anammox (anaerobic ammonium oxidation) is an important process in many suboxic to anoxic marine environments for converting fixed nitrogen to N2,and has a major impact on the marine nitrogen cycle.Ladderane core lipids have been utilized as an indicator of the contribution of anammox to the marine nitrogen cycles.However,such studies have not been reported for the China seas and little is known about the importance ofanammox within the nitrogen cycle of these marginal seas.In the research reported here,the ladderane core lipid contents of 17 surface sediment samples from the East China Sea are reported,and their spatial distribution is investigated.C1s-[5]-ladderane FAME,C20-[5]-ladderane FAME and C20-[3]-ladderane FAME have all been detected,suggesting that the anammox bacteria are widely present within the study area.The total contents of the three ladderane lipids (ΣFAMEs) range from 24-355 ng/g (weight of dry sediments),with higher contents occurring in the Minzhe Mud Zone and broadly coincident with the spatial distribution of hypoxia.It is suggested that the sedimentary ladderane core lipids are mainly produced in the water column and their sedimentary contents can be used as indicators of water colunm hypoxia.

  12. Deficits in Facial Emotion Recognition Indicate Behavioral Changes and Impaired Self-Awareness after Moderate to Severe Traumatic Brain Injury

    NARCIS (Netherlands)

    Spikman, Jacoba M.; Milders, Maarten V.; Visser-Keizer, Annemarie C.; Westerhof-Evers, Herma J.; Herben-Dekker, Meike; van der Naalt, Joukje

    2013-01-01

    Traumatic brain injury (TBI) is a leading cause of disability, specifically among younger adults. Behavioral changes are common after moderate to severe TBI and have adverse consequences for social and vocational functioning. It is hypothesized that deficits in social cognition, including facial aff

  13. Variations in Environmental Signals in Tree-Ring Indices in Trees with Different Growth Potential.

    Directory of Open Access Journals (Sweden)

    Polona Hafner

    Full Text Available We analysed two groups of Quercus robur trees, growing at nearby plots with different micro-location condition (W-wet and D-dry in the floodplain Krakovo forest, Slovenia. In the study we compared the growth response of two different tree groups to environmental variables, the potential signal stored in earlywood (EW structure and the potential difference of the information stored in carbon isotope discrimination of EW and latewood (LW. For that purpose EW and LW widths and carbon isotope discrimination for the period 1970-2008 AD were measured. EW and LW widths were measured on stained microscopic slides and chronologies were standardised using the ARSTAN program. α-cellulose was extracted from pooled EW and LW samples and homogenized samples were further analysed using an elemental analyser and IRMS. We discovered that W oaks grew significantly better over the whole analysed period. The difference between D and W oaks was significant in all analysed variables with the exception of stable carbon isotope discrimination in latewood. In W oaks, latewood widths correlated with summer (June to August climatic variables, while carbon isotope discrimination was more connected to River Krka flow during the summer. EW discrimination correlated with summer and autumn River Krka flow of the previous year, while latewood discrimination correlated with flow during the current year. In the case of D oaks, the environmental signal appears to be vague, probably due to less favourable growth conditions resulting in markedly reduced increments. Our study revealed important differences in responses to environmental factors between the two oak groups of different physiological conditions that are preconditioned by environmental stress. Environmental information stored in tree-ring features may vary, even within the same forest stand, and largely depends on the micro-environment. Our analysis confirmed our assumptions that separate EW and LW analysis of widths and

  14. Lead isotopes in teeth as indicators of past domicile - a potential new tool in forensic science?

    International Nuclear Information System (INIS)

    The isotopic signature for Australian subjects is based mainly on deciduous teeth analyses, especially teeth for 'non-exposed' children from the Broken Hill mining community. For 'non-exposed' children from Broken Hill and several other adults and children from varying locations, the mean 206Pb/204Pb and 207Pb/206Pb ratios are 16.56 and 0.9318 respectively. These data are consistent with values for the isotopic composition of lead in blood obtained from over 200 Australian subjects (Gulson et al., 1995). From comparisons of permanent and deciduous teeth, the isotopic composition has remained remarkably uniform over more than a 30-year period, indicated by the relatively small standard deviation for the data

  15. Complete mitogenome of the foxface rabbitfish Siganus vulpinus (Perciformes, Siganidae): indication of potential interbreeding in rabbitfishes.

    Science.gov (United States)

    Yan, Shuai; Wang, Ming; Yang, Tingbao

    2016-05-01

    In the present study, the complete mitochondrial genome of the foxface rabbitfish Siganus vulpinus (Perciformes, Siganidae) is determined. The entire sequence is 16,505 bp in length, including 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and 1 control region. The genome organization is similar to those found in other rabbitfishes. Apart from ND6 and 8 tRNA genes, all other mitochondrial genes are encoded on the heavy strand. Overall base compositions of mitogenome are 29.3% of A, 29.3% of C, 25.7% of T, and 15.7% of G, showing an obvious anti-G bias which is commonly found in fishes. The high similarity of mitochondrial genome between S. vulpinus and S. unimaculatus indicate that natural interbreeding might exist in breeding season.

  16. Simultaneous functional near-infrared brain imaging and event-related potential studies of Stroop effect

    Science.gov (United States)

    Zhai, Jiahuan; Li, Ting; Zhang, Zhongxing; Gong, Hui

    2009-02-01

    Functional near-infrared brain imaging (fNIRI) and event-related potential (ERP) were used simultaneous to detect the prefrontal cortex (PFC) which is considered to execute cognitive control of the subjects while performing the Chinese characters color-word matching Stroop task with event-related design. The fNIRI instrument is a portable system operating at three wavelengths (735nm & 805nm &850nm) with continuous-wave. The event-related potentials were acquired by Neuroscan system. The locations of optodes corresponding to the electrodes were defined four areas symmetrically. In nine native Chinese-speaking fit volunteers, fNIRI measured the hemodynamic parameters (involving oxy-/deoxy- hemoglobin) changes when the characteristic waveforms (N500/P600) were recorded by ERP. The interference effect was obvious as a longer reaction time for incongruent than congruent and neutral stimulus. The responses of hemodynamic and electrophysiology were also stronger during incongruent compared to congruent and neutral trials, and these results are similar to those obtained with fNIRI or ERP separately. There are high correlations, even linear relationship, in the two kinds of signals. In conclusion, the multi-modality approach combining of fNIRI and ERP is feasible and could obtain more cognitive function information with hemodynamic and electrophysiology signals. It also provides a perspective to prove the neurovascular coupling mechanism.

  17. The Autonomous Stress Indicator for Remotely Monitoring Power System State and Watching for Potential Instability

    Directory of Open Access Journals (Sweden)

    Geza Joos

    2009-02-01

    Full Text Available The proposed Autonomous Stress Indicator (ASI is a device that monitors the contents of the protection relays on a suspect weak power system bus and generates a performance level related to the degree of system performance degradation or instability. This gives the system operators some time (minutes to take corrective action. In a given operating area there would not likely be a need for an ASI on every bus. Note that the ASI does not trip any breakers; it is an INFORMATION ONLY device. An important feature is that the system operator can subsequently interrogate the ASI to determine the factor(s that led to the performance level that has been initially annunciated, thereby leading to a course of action. This paper traces the development of the ASI which is an ongoing project. The ASI could be also described as a stress-alert device whose function is to alert the System Operator of a stressful condition at its location. The characteristics (or essential qualities of this device are autonomy, selectivity, accuracy and intelligence. These will fulfill the requirements of the recommendation of the Canada –US Task Force in the August 2003 system collapse. Preliminary tests on the IEEE 39-bus model indicate that the concept has merit and development work is in progress. While the ASI can be applied to all power system operating conditions, its principal application is to the degraded state of the system where the System Operator must act to restore the system to the secure state before it migrates to a stage of collapse. The work of ASI actually begins with the Areas of Vulnerability and ends with the Predictive Module as described in detail in this paper. An application example of a degraded system using the IEEE 39-bus system is included.

  18. Using indicator kriging for the evaluation of arsenic potential contamination in an abandoned mining area (Portugal).

    Science.gov (United States)

    Antunes, I M H R; Albuquerque, M T D

    2013-01-01

    Mining and mineral-processing activities can modify the environment in a variety of ways. Sulfide mineralization is notorious for producing waters with high metal contents. Arsenic is commonly associated with sulfide mineralization and is considered to be toxic in the environment at low levels. The studied abandoned mining area is located in central Portugal and the resulting tailings and rejected materials were deposited and exposed to the air and water for the last 50 years. Sixteen water sample-points were collected. One of these was collected outside the mining influence, with the aim of obtaining a reference background. The risk assessment, concerning the proximity to abandoned mineralized deposits, needs the evaluation of intrinsic and specific vulnerabilities aiming the quantification of the anthropogenic activities. In this study, two indicator variables were constructed. The first one (I(1)), a specific vulnerability, considers the arsenic water supply standard value (0.05 mg/L), and the probability of it being exceeded is dependent on the geologic and hydrological characteristics of the studied area and also on the anthropogenic activities. The second one (I(2)), an intrinsic vulnerability, considers arsenic background limit as cut-off value, and depends only on the geologic and hydro-geological characteristics of the studied area. At Segura, the arsenic water content found during December 2006 (1.190 mg/L) was higher than the arsenic water content detected in October 2006 (0.636 mg/L) which could be associated to the arsenic released from Fe oxy-hydroxide. At Segura abandoned mining area, the iso-probability maps of October 2006 and December 2006, show strong anomalies associated with the water drainage from abandoned mining activities. Near the village, the probability of exceeding the arsenic background value is high but lower than the probability of exceeding the arsenic water supply value. The arsenic anomalies indicate a high probability for water

  19. Menopausal symptoms among breast cancer patients: a potential indicator of favorable prognosis.

    Directory of Open Access Journals (Sweden)

    Yong Chen

    Full Text Available Menopausal symptoms have been suggested to be an indicator of better prognosis among patients treated for breast cancer, because women who experience these symptoms usually have a lower level of estrogen. We tested this hypothesis in a population-based, prospective cohort study involving 4,842 women with stage 0 to III primary breast cancer who were enrolled in the Shanghai Breast Cancer Survival Study between March 2002 and April 2006, were aged 20 to 75 years, and were recruited 6 months post-diagnosis. They were followed-up by in-person surveys and record linkages with the vital statistics registry. Cox regression analysis was used to evaluate the association of menopausal symptoms at baseline with breast cancer recurrence. Approximately 56% of patients experienced at least one menopausal symptom, including hot flashes, night sweats, and/or vaginal dryness at baseline. During a median follow-up period of 5.3 years, 720 women had a recurrence. Experiencing hot flashes or having ≥2 menopausal symptoms was associated with lower risk of recurrence among premenopausal women (hazard ratio [HR]=0.77, 95% confidence interval [CI]: 0.62-0.96 for hot flashes; 0.73, 0.56-0.96 for ≥2 menopausal symptoms. Lower recurrence risk in relation to hot flashes was also observed among women who were not overweight/obese (HR=0.78, 95% CI: 0.64-0.99, those with relatively low waist-to-hip ratio (WHR (HR=0.77, 95% CI: 0.61-0.97, and those who used tamoxifen (HR=0.75, 95% CI: 0.58-0.98. Consistently experiencing multiple menopausal symptoms was associated with lower recurrence risk among women with low WHR or who used tamoxifen. This large, population-based cohort study of women with breast cancer confirms that experiencing menopausal symptoms is an indicator of favorable breast cancer prognosis.

  20. Steady state visually evoked potentials based Brain computer interface test outside the lab

    Directory of Open Access Journals (Sweden)

    Eduardo Francisco Caicedo Bravo

    2016-06-01

    Full Text Available Context: Steady State Visually Evoked Potentials (SSVEP are brain signals which are one of the most promising signals for Brain Computer Interfaces (BCIs implementation, however, SSVEP based BCI generally are proven in a controlled environment and there are a few tests in demanding conditions.Method: We present a SSVEP based BCI system that was used outside the lab in a noisy environment with distractions, and with the presence of public. For the tests, we showed a maze in a laptop where the user could move an avatar looking for a target that is represented by a house.  In order to move the avatar, the volunteer must stare at one of the four visual stimuli; the four visual stimuli represent the four directions: right, up, left, and down. The system is proven without any calibration procedure.Results: 32 volunteers utilized the system and 20 achieved the target with an accuracy above 60%, including 9 with an accuracy of 100%, 7 achieved the target with an accuracy below 60% and 5 left without achieving the goal. For the volunteers who reached accuracy above 60%, the results of the performance achieved an average of 6,4s for command detections, precision of 79% and information transfer rate (ITR of 8,78 bits/s.Conclusions: We showed a SSVEP based BCI system with low cost, it was proved in a public event, it did not have calibration procedures, it was easy to install, and it was used for people in a wide age range. The results show that it is possible to bring this kind of systems to environments outside the laboratory.

  1. Multivariate evaluation of brain function by measuring regional cerebral blood flow and event-related potentials

    Energy Technology Data Exchange (ETDEWEB)

    Koga, Yoshihiko; Mochida, Masahiko; Shutara, Yoshikazu; Nakagawa, Kazumi [Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine; Nagata, Ken

    1998-07-01

    To measure the effect of events on human cognitive function, effects of odors by measurement regional cerebral blood flow (rCBF) and P300 were evaluated during the auditory odd-ball exercise. PET showed the increase in rCBF on the right hemisphere of the brain by coffee aroma. rCBF was measured by PET in 9 of right-handed healthy adults men, and P300 was by event-related potential (ERP) in each sex of 20 right-handed healthy adults. ERP showed the difference of the P300 amplitude between men and women, and showed the tendency, by odors except the lavender oil, that women had higher in the P300 amplitude than men. These results suggest the presence of effects on the cognitive function through emotional actions. Next, the relationship between rCBF and ERP were evaluated. The subjects were 9 of the right-handed healthy adults (average: 25.6{+-}3.4 years old). rCBF by PET and P300 amplitude by ERP were simultaneously recorded during the auditory odd-ball exercise using the tone-burst method (2 kHz of the low frequency aimed stimuli and 1 kHz of the high frequency non-aimed stimuli). The rCBF value was the highest at the transverse gyrus of Heschl and the lowest at the piriform cortex among 24 regions of interest (ROI) from both sides. The difference of P300 peak latent time among ROI was almost the same. The brain waves from Cz and Pz were similar and the average amplitude was highest at Pz. We found the high correlation in the right piriform cortex (Fz), and right (Fz, Cz) and left (Cz, Pz) transverse gyrus of Heschl between the P300 amplitude and rCBF. (K.H.)

  2. Multivariate evaluation of brain function by measuring regional cerebral blood flow and event-related potentials

    International Nuclear Information System (INIS)

    To measure the effect of events on human cognitive function, effects of odors by measurement regional cerebral blood flow (rCBF) and P300 were evaluated during the auditory odd-ball exercise. PET showed the increase in rCBF on the right hemisphere of the brain by coffee aroma. rCBF was measured by PET in 9 of right-handed healthy adults men, and P300 was by event-related potential (ERP) in each sex of 20 right-handed healthy adults. ERP showed the difference of the P300 amplitude between men and women, and showed the tendency, by odors except the lavender oil, that women had higher in the P300 amplitude than men. These results suggest the presence of effects on the cognitive function through emotional actions. Next, the relationship between rCBF and ERP were evaluated. The subjects were 9 of the right-handed healthy adults (average: 25.6±3.4 years old). rCBF by PET and P300 amplitude by ERP were simultaneously recorded during the auditory odd-ball exercise using the tone-burst method (2 kHz of the low frequency aimed stimuli and 1 kHz of the high frequency non-aimed stimuli). The rCBF value was the highest at the transverse gyrus of Heschl and the lowest at the piriform cortex among 24 regions of interest (ROI) from both sides. The difference of P300 peak latent time among ROI was almost the same. The brain waves from Cz and Pz were similar and the average amplitude was highest at Pz. We found the high correlation in the right piriform cortex (Fz), and right (Fz, Cz) and left (Cz, Pz) transverse gyrus of Heschl between the P300 amplitude and rCBF. (K.H.)

  3. Executive dysfunctions and event-related brain potentials in patients with amyotrophic lateral sclerosis

    Directory of Open Access Journals (Sweden)

    Caroline eSeer

    2015-12-01

    Full Text Available A growing body of evidence implies psychological disturbances in amyotrophic lateral sclerosis (ALS. Specifically, executive dysfunctions occur in up to 50% of ALS patients. The recently shown presence of cytoplasmic aggregates (TDP-43 in ALS patients and in patients with behavioral variants of frontotemporal dementia suggests that these two disease entities form the extremes of a spectrum. The present study aimed at investigating behavioral and electrophysiological indices of conflict processing in patients with ALS. A non-verbal variant of the flanker task demanded two-choice responses to target stimuli that were surrounded by flanker stimuli which either primed the correct response or the alternative response (the latter case representing the conflict situation. Behavioral performance, event-related potentials (ERP, and lateralized readiness potentials (LRP were analyzed in 21 ALS patients and 20 controls. In addition, relations between these measures and executive dysfunctions were examined. ALS patients performed the flanker task normally, indicating preserved conflict processing. In similar vein, ERP and LRP indices of conflict processing did not differ between groups. However, ALS patients showed enhanced posterior negative ERP waveform deflections, possibly indicating increased modulation of visual processing by frontoparietal networks in ALS. We also found that the presence of executive dysfunctions was associated with more error-prone behavior and enhanced LRP amplitudes in ALS patients, pointing to a prefrontal pathogenesis of executive dysfunctions and to a potential link between prefrontal and motor cortical functional dysregulation in ALS, respectively.

  4. Indices of adrenal deficiency involved in brain plasticity and functional control reorganization in hemodialysis patients with polysulfone membrane: BOLD-fMRI study.

    Science.gov (United States)

    Belaïch, Rachida; Boujraf, Saïd; Benzagmout, Mohammed; Maaroufi, Mustapha; Housni, Abdelkhalek; Batta, Fatima; Tizniti, Siham; Magoul, Rabia; Sqalli, Tarik

    2016-06-01

    This work purpose was to estimate the implication of suspected adrenal function deficiencies, which was influenced by oxidative stress (OS) that are generating brain plasticity, and reorganization of the functional control. This phenomenon was revealed in two-hemodialysis patients described in this paper. Blood oxygenation level dependent functional magnetic resonance imaging (BOLD-fMRI) revealed a significant activation of the motor cortex. Hemodialysis seems to originate an inflammatory state of the cerebral tissue reflected by increased OS, while expected to decrease since hemodialysis eliminates free radicals responsible for OS. Considering adrenal function deficiencies, sensitivity to OS and assessed hyponatremia and hypercalcemia, adrenal function deficiencies is strongly suspected in both patients. This probably contributes to amplify brain plasticity and a reorganization of functional control after hemodialysis that is compared to earlier reported studies. Brain plasticity and functional control reorganization was revealed by BOLD-fMRI with a remarkable sensitivity. Brain plastic changes are originated by elevated OS associating indices of adrenal function deficiencies. These results raise important issues about adrenal functional deficiencies impact on brain plasticity in chronic hemodialysis-patients. This motivates more global studies of plasticity induced factors in this category of patients including adrenal functional deficiencies and OS. PMID:27301905

  5. Ultra-slow frequency bands reflecting potential coherence between neocortical brain regions.

    Science.gov (United States)

    Zhang, X; Wang, Y-T; Wang, Y; Jung, T P; Huang, M; Cheng, C K; Mandell, A J

    2015-03-19

    Recent studies of electromagnetic ultra-slow waves (⩽0.1Hz) have suggested that they play a role in the integration of otherwise disassociated brain regions supporting vital functions (Ackermann and Borbely, 1997; Picchioni et al., 2010; Knyazev, 2012; Le Bon et al., 2012). We emphasize this spectral domain in probing sensor coherence issues raised by these studies using Hilbert phase coherences in the human MEG. In addition, we ask: will temporal-spatial phase coherence in regional brain oscillations obtained from the ultraslow spectral bands of multi-channel magnetoencephalograms (MEG) differentiate resting, "task-free" MEG records of normal control and schizophrenic subjects? The goal of the study is a comparison of the relative persistence of intra-regional phase locking values (PLVs), among 10, region-defined, sensors in examined in the resting multichannel, MEG records as a function of spectral frequency bands and diagnostic category. The following comparison of Hilbert-transform-engendered relative phases of each designated spectral band was made using their pair-wise PLVs. This indicated the proportion of shared cycle time in which the phase relations between the index location and reference leads were maintained. Leave one out, bootstrapping of the PLVs via a support vector machine (SVM), classified clinical status with 97.3% accuracy. It was generally the case that spectral bands ⩽1.0Hz generated the highest values of the PLVs and discriminated best between control and patient populations. We conclude that PLV analysis of the oscillatory patterns of MEG recordings in the ultraslow frequency bands suggest their functional significance in intra-regional signal coherence and provide a higher rate of classification of patients and normal subjects than the other spectral domains examined. PMID:25592429

  6. Conserved B-cell epitopes among human bocavirus species indicate potential diagnostic targets.

    Directory of Open Access Journals (Sweden)

    Zhuo Zhou

    Full Text Available BACKGROUND: Human bocavirus species 1-4 (HBoV1-4 have been associated with respiratory and enteric infections in children. However, the immunological mechanisms in response to HBoV infections are not fully understood. Though previous studies have shown cross-reactivities between HBoV species, the epitopes responsible for this phenomenon remain unknown. In this study, we used genomic and immunologic approaches to identify the reactive epitopes conserved across multiple HBoV species and explored their potential as the basis of a novel diagnostic test for HBoVs. METHODOLOGY/PRINCIPAL FINDINGS: We generated HBoV1-3 VP2 gene fragment phage display libraries (GFPDLs and used these libraries to analyze mouse antisera against VP2 protein of HBoV1, 2, and 3, and human sera positive for HBoVs. Using this approach, we mapped four epitope clusters of HBoVs and identified two immunodominant peptides--P1 (¹MSDTDIQDQQPDTVDAPQNT²⁰, and P2 (¹⁶²EHAYPNASHPWDEDVMPDL¹⁸⁰--that are conserved among HBoV1-4. To confirm epitope immunogenicity, we immunized mice with the immunodominant P1 and P2 peptides identified in our screen and found that they elicited high titer antibodies in mice. These two antibodies could only recognize the VP2 of HBoV 1-4 in Western blot assays, rather than those of the two other parvoviruses human parvovirus B19 and human parvovirus 4 (PARV4. Based on our findings, we evaluated epitope-based peptide-IgM ELISAs as potential diagnostic tools for HBoVs IgM antibodies. We found that the P1+P2-IgM ELISA showed a higher sensitivity and specificity in HBoVs IgM detection than the assays using a single peptide. CONCLUSIONS/SIGNIFICANCE: The identification of the conserved B-cell epitopes among human bocavirus species contributes to our understanding of immunological cross-reactivities of HBoVs, and provides important insights for the development of HBoV diagnostic tools.

  7. Noradrenaline acting on alpha1-adrenoceptor mediates REM sleep deprivation-induced increased membrane potential in rat brain synaptosomes.

    Science.gov (United States)

    Das, Gitanjali; Mallick, Birendra Nath

    2008-01-01

    We hypothesized that one of the functions of REM sleep is to maintain brain excitability and therefore, REM sleep deprivation is likely to modulate neuronal transmembrane potential; however, so far there was no direct evidence to support the claim. In this study a cationic dye, 3,3'-diethylthiacarbocyanine iodide was used to estimate the potential in synaptosomal samples prepared from control and REM sleep deprived rat brains. The activity of Na-K-ATPase that maintains the transmembrane potential was also estimated in the same sample. Further, the roles of noradrenaline and alpha1-adrenoceptor in mediating the responses were studied both in vivo as well as in vitro. Rats were REM sleep deprived for 4 days by the classical flower-pot method; large platform and recovery controls were carried out in addition to free-moving control. The fluorescence intensity increased in samples prepared from REM sleep deprived rat brain as compared to control, which reflected synaptosomal depolarization after deprivation. The Na-K-ATPase activity also increased in the same deprived sample. Furthermore, both the effects were mediated by noradrenaline acting on alpha1-adrenoceptors in the brain. This is the first direct evidence showing that REM sleep deprivation indeed increased neuronal depolarization, which is the likely cause for increased brain excitability, thus supporting our hypothesis and the effect was mediated by noradrenaline acting through the alpha1-adrenoceptor.

  8. Surveillance indicators for potential reduced exposure products (PREPs: developing survey items to measure awareness

    Directory of Open Access Journals (Sweden)

    McNeill Ann

    2009-10-01

    Full Text Available Abstract Background Over the past decade, tobacco companies have introduced cigarettes and smokeless tobacco products (known as Potential Reduced Exposure Products, PREPs with purportedly lower levels of some toxins than conventional cigarettes and smokeless products. It is essential that public health agencies monitor awareness, interest, use, and perceptions of these products so that their impact on population health can be detected at the earliest stages. Methods This paper reviews and critiques existing strategies for measuring awareness of PREPs from 16 published and unpublished studies. From these measures, we developed new surveillance items and subjected them to two rounds of cognitive testing, a common and accepted method for evaluating questionnaire wording. Results Our review suggests that high levels of awareness of PREPs reported in some studies are likely to be inaccurate. Two likely sources of inaccuracy in awareness measures were identified: 1 the tendency of respondents to misclassify "no additive" and "natural" cigarettes as PREPs and 2 the tendency of respondents to mistakenly report awareness as a result of confusion between PREPs brands and similarly named familiar products, for example, Eclipse chewing gum and Accord automobiles. Conclusion After evaluating new measures with cognitive interviews, we conclude that as of winter 2006, awareness of reduced exposure products among U.S. smokers was likely to be between 1% and 8%, with the higher estimates for some products occurring in test markets. Recommended measurement strategies for future surveys are presented.

  9. Soil fungal community shift evaluation as a potential cadaver decomposition indicator.

    Science.gov (United States)

    Chimutsa, Monica; Olakanye, Ayodeji O; Thompson, Tim J U; Ralebitso-Senior, T Komang

    2015-12-01

    Fungi metabolise organic matter in situ and so alter both the bio-/physico-chemical properties and microbial community structure of the ecosystem. In particular, they are responsible reportedly for specific stages of decomposition. Therefore, this study aimed to extend previous bacteria-based forensic ecogenomics research by investigating soil fungal community and cadaver decomposition interactions in microcosms with garden soil (20 kg, fresh weight) and domestic pig (Sus scrofa domesticus) carcass (5 kg, leg). Soil samples were collected at depths of 0-10 cm, 10-20 cm and 20-30 cm on days 3, 28 and 77 in the absence (control -Pg) and presence (experimental +Pg) of Sus scrofa domesticus and used for total DNA extraction and nested polymerase chain reaction and denaturing gradient gel electrophoresis (PCR-DGGE) profiling of the 18S rRNA gene. The Shannon-Wiener (H') community diversity indices were 1.25±0.21 and 1.49±0.30 for the control and experimental microcosms, respectively, while comparable Simpson species dominance (S) values were 0.65±0.109 and 0.75±0.015. Generally, and in contrast to parallel studies of the bacterial 16S rRNA and 16S rDNA profiles, statistical analysis (t-test) of the 18S dynamics showed no mathematically significant shifts in fungal community diversity (H'; p=0.142) and dominance (S; p=0.392) during carcass decomposition, necessitating further investigations.

  10. Indications for potential parent-of-origin effects within the FTO gene.

    Directory of Open Access Journals (Sweden)

    Xuanshi Liu

    Full Text Available Genome-Wide Association Studies (GWAS were successfully applied to discover associations with obesity. However, the GWAS design is usually based on unrelated individuals and inheritance information on the parental origin of the alleles is missing. Taking into account parent-of-origin may provide further insights into the genetic mechanisms contributing to obesity. We hypothesized that there may be variants within the robustly replicated fat mass and obesity associated (FTO gene that may confer different risk for obesity depending on transmission from mother or father. Genome-wide genotypes and pedigree information from the Sorbs population were used. Phased genotypes among 525 individuals were generated by AlphaImpute. Subsequently, 22 SNPs within FTO introns 1 to 3 were selected and parent-of-origin specific association analyses were performed using PLINK. Interestingly, we identified several SNPs conferring different genetic effects (P≤0.05 depending on parental origin--among them, rs1861868, rs1121980 and rs9939973 (all in intron 1. To confirm our findings, we investigated the selected variants in 705 German trios comprising an (extremely obese child or adolescent and both parents. Again, we observed evidence for POE effects in intron 2 and 3 (P≤0.05 as indicated by the parental asymmetry test. Our results suggest that the obesity risk transmitted by several FTO variants may depend on the parental origin of the allele. Larger family-based studies are warranted to replicate our findings.

  11. Mycobacterium bovis DNA detection in colostrum as a potential indicator of vaccination effectiveness against bovine tuberculosis.

    Science.gov (United States)

    Herrera-Rodríguez, Sara E; Gordiano-Hidalgo, María Alejandra; López-Rincón, Gonzálo; Bojorquez-Narváez, Luis; Padilla-Ramírez, Francisco Javier; Pereira-Suárez, Ana Laura; Flores-Valdez, Mario Alberto; Estrada-Chávez, Ciro

    2013-04-01

    Bovine tuberculosis (bTB) remains a problem on many dairy farms in Mexico, as well as a public health risk. We previously found a high frequency of Mycobacterium bovis DNA in colostrum from dairy cows using a nested PCR to detect mpb70. Since there are no reliable in vivo tests to determine the effectiveness of booster Mycobacterium bovis BCG vaccination against bTB, in this work we monitored M. bovis DNA in colostrum by using this nested PCR. In order to decrease the risk of adverse reactions in animals likely containing viable M. bovis, a single application of BCG and a subunit vaccine (EEP-1) formulated with M. bovis culture filtrate proteins (CFP) and a copolymer as the adjuvant was performed in tuberculin skin test-negative cattle (TST(-)), while TST reactor animals (TST(+)) received EEP-1 only. Booster immunization using EEP-1 was applied to both groups, 2 months after primary vaccination to whole herds and 12 months later to lactating cows. Colostrum samples were collected from 6 farms where the cows were vaccinated over a 12-month period postvaccination and, for comparison, from one control farm where the cows were not vaccinated with comparable bTB prevalence. We observed an inverse relationship between the frequency of M. bovis DNA detection and time postvaccination at the first (P < 0.001) and second (P < 0.0001) 6-month periods. Additionally, the concentration of gamma interferon (IFN-γ) was higher in mpb70 PCR-positive colostrum samples (P = 0.0003). These results suggest that M. bovis DNA frequency in colostrum could be a potentially useful biomarker for bTB vaccine efficacy on commercial dairy farms. PMID:23425597

  12. Dissolved Organic Carbon and Optical Properties as Indicators of Trihalomethane Formation Potential in an Agricultural Watershed

    Science.gov (United States)

    Pellerin, B. A.; Bergamaschi, B. A.; Spencer, R. G.

    2006-12-01

    Elevated concentrations of dissolved organic carbon (DOC) in the Sacramento-San Joaquin Delta waters may result in the formation of high levels of carcinogenic disinfection byproducts such as trihalomethane during drinking water treatment. The importance of Central Valley agricultural lands as sources of DOC and THM- precursors upstream of the Delta is presently unknown. We are quantifying contributions of DOC and THM- precursors from the Willow Slough watershed, a 425 km2 agriculturally-dominated catchment. During 2006, water samples were collected weekly at the mouth of the watershed and analyzed for DOC concentrations, optical properties (UV absorbance and fluorescence), and trihalomethane formation potential (THMFP). Additional synoptic samples were collected seasonally (winter, spring, summer) from 16 watershed locations and analyzed for optical properties, DOC concentrations, and THMFP. DOC concentrations generally ranged from approximately 2 to 4 mg/L at the watershed outlet during winter and spring, but increased weekly to 8 mg/L following the onset of irrigation. The THMFP at the mouth of the water was correlated with DOC concentration (r2 = 0.87), with higher concentrations during high discharge events and lower concentrations during summer and prolonged rain-free periods. In addition, the species of THM varied between high and low-flow periods, with THM formation dominated by brominated species during low- flow periods and chlorinated species during rainfall-runoff events. Optical characterization of DOC via UV absorbance and fluorescence suggests changes in DOC composition between high- and low-flow periods, likely reflective of changing sources and flowpaths of runoff.

  13. Hypofractionated stereotactic radiotherapy for brain metastases from lung cancer. Evaluation of indications and predictors of local control

    Energy Technology Data Exchange (ETDEWEB)

    Ishihara, Takeaki [Kobe University Graduate School of Medicine, Division of Radiation Oncology, Hyogo (Japan); Seirei Mikatahara General Hospital, Department of Radiation Oncology, Shizuoka (Japan); Yamada, Kazunari; Isogai, Kenta; Tonosaki, Yoshihiro [Seirei Mikatahara General Hospital, Department of Radiation Oncology, Shizuoka (Japan); Harada, Aya [Kobe Minimum Invasive Cancer Medical Center, Department of Radiation Oncology, Hyogo (Japan); Demizu, Yusuke [Hyogo Ion Beam Medical Center, Department of Radiology, Hyogo (Japan); Miyawaki, Daisuke; Yoshida, Kenji; Ejima, Yasuo; Sasaki, Ryohei [Kobe University Graduate School of Medicine, Division of Radiation Oncology, Hyogo (Japan)

    2016-06-15

    To evaluate the efficacy and toxicity of hypofractionated stereotactic radiotherapy (HSRT) for brain metastases (BMs) from lung cancer, and to explore prognostic factors associated with local control (LC) and indication. We evaluated patients who were treated with linac-based HSRT for BMs from lung cancer. Lesions treated with stereotactic radiosurgery (SRS) in the same patients during the same periods were analysed and compared with HSRT in terms of LC or toxicity. There were 53 patients with 214 lesions selected for this analysis (HSRT: 76 lesions, SRS: 138 lesions). For HSRT, the median prescribed dose was 35 Gy in 5 fractions. The 1-year LC rate was 83.6 % in HSRT; on multivariate analysis, a planning target volume (PTV) of <4 cm{sup 3}, biologically effective dose (BED{sub 10}) of ≥51 Gy, and adenocarcinoma were significantly associated with better LC. Moreover, in PTVs ≥ 4 cm{sup 3}, there was a significant difference in LC between BED{sub 10} < 51 Gy and ≥ 51 Gy (p = 0.024). On the other hand, in PTVs < 4 cm{sup 3}, both HSRT and SRS had good LC with no significant difference (p = 0.195). Radiation necrosis emerged in 5 of 76 lesions (6.6 %) treated with HSRT and 21 of 138 (15.2 %) lesions treated with SRS (p = 0.064). Linac-based HSRT was safe and effective for BMs from lung cancer, and hence might be particularly useful in or near an eloquent area. PTV, BED{sub 10}, and pathological type were significant prognostic factors. Furthermore, in BMs ≥ 4 cm{sup 3}, a dose of BED ≥ 51 Gy should be considered. (orig.) [German] Beurteilung von Wirksamkeit und Toxizitaet einer hypofraktionierten stereotaktischen Strahlentherapie (HSRT) zur Behandlung von Hirnmetastasen (HM) eines Lungenkarzinoms und Erforschung von mit der lokalen Kontrolle (LK) und der Indikation assoziierten Prognosefaktoren. Analysiert wurden Daten von Patienten (n = 53), die sich einer Linearbeschleuniger-basierten HSRT unterzogen (mit HSRT behandelte Laesionen n = 76; Median der

  14. Perceived Accessibility of Public Transport as a Potential Indicator of Social Inclusion

    Directory of Open Access Journals (Sweden)

    Katrin Lättman

    2016-06-01

    Full Text Available Perceived accessibility has been acknowledged as an important aspect of transport policy since the 70s. Nevertheless, very few empirical studies have been conducted in this field. When aiming to improve social inclusion, by making sustainable transport modes accessible to all, it is important to understand the factors driving perceived accessibility. Unlike conventional accessibility measures, perceived accessibility focuses on the perceived possibilities and ease of engaging in preferred activities using different transport modes. We define perceived accessibility in terms of how easy it is to live a satisfactory life with the help of the transport system, which is not necessarily the same thing as the objective standard of the system. According to previous research, perceived accessibility varies with the subjectively-rated quality of the mode of transport. Thus, improvements in quality (e.g. trip planning, comfort, or safety increase the perceived accessibility and make life easier to live using the chosen mode of transport. This study (n=750 focuses on the perceived accessibility of public transport, captured using the Perceived Accessibility Scale PAC (Lättman, Olsson, & Friman, 2015. More specifically, this study aims to determine how level of quality affects the perceived accessibility in public transport. A Conditional Process Model shows that, in addition to quality, feeling safe and frequency of travel are important predictors of perceived accessibility. Furthermore, elderly and those in their thirties report a lower level of perceived accessibility to their day-to-day activities using public transport. The basic premise of this study is that subjective experiences may be as important as objective indicators when planning and designing for socially inclusive transport systems.

  15. Soil fungal community shift evaluation as a potential cadaver decomposition indicator.

    Science.gov (United States)

    Chimutsa, Monica; Olakanye, Ayodeji O; Thompson, Tim J U; Ralebitso-Senior, T Komang

    2015-12-01

    Fungi metabolise organic matter in situ and so alter both the bio-/physico-chemical properties and microbial community structure of the ecosystem. In particular, they are responsible reportedly for specific stages of decomposition. Therefore, this study aimed to extend previous bacteria-based forensic ecogenomics research by investigating soil fungal community and cadaver decomposition interactions in microcosms with garden soil (20 kg, fresh weight) and domestic pig (Sus scrofa domesticus) carcass (5 kg, leg). Soil samples were collected at depths of 0-10 cm, 10-20 cm and 20-30 cm on days 3, 28 and 77 in the absence (control -Pg) and presence (experimental +Pg) of Sus scrofa domesticus and used for total DNA extraction and nested polymerase chain reaction and denaturing gradient gel electrophoresis (PCR-DGGE) profiling of the 18S rRNA gene. The Shannon-Wiener (H') community diversity indices were 1.25±0.21 and 1.49±0.30 for the control and experimental microcosms, respectively, while comparable Simpson species dominance (S) values were 0.65±0.109 and 0.75±0.015. Generally, and in contrast to parallel studies of the bacterial 16S rRNA and 16S rDNA profiles, statistical analysis (t-test) of the 18S dynamics showed no mathematically significant shifts in fungal community diversity (H'; p=0.142) and dominance (S; p=0.392) during carcass decomposition, necessitating further investigations. PMID:26322496

  16. Evaluating stakeholder participation in water management: intermediary outcomes as potential indicators for future resource management outcomes

    Science.gov (United States)

    Carr, Gemma; Bloeschl, Guenter; Loucks, Daniel Pete

    2013-04-01

    . Furthermore, failure to achieve intermediary outcomes correlates to failure to achieve resource management outcomes. Evaluating intermediary outcomes leads to both a broader assessment of a programme's achievements at the time of evaluation, and can indicate whether a programme will go on to achieve resource management objectives in the future.

  17. Potential new approaches for the development of brain imaging agents for single-photon applications

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, F.F. Jr.; Srivastava, P.C.

    1984-01-01

    This paper describes new strategies for the brain-specific delivery of radionuclides that can be used to evaluate regional cerebral perfusion by single photon imaging techniques. A description of several examples of interesting new strategies that have recently been reported is presented. A new approach at this institution for the brain-specific delivery of radioiodinated iodophenylalkyl-substituted dihyronicotinamide systems is described which shows good brain uptake and retention in preliminary studies in rats. Following transport into the brain these agents appear to undergo facile intracerebral oxidation to the quaternized analogues which do not recross the intact blood-brain barrier and so are effectively trapped in the brain. 49 refs., 9 figs., 1 tab.

  18. Banking (on) the brain: from consent to authorisation and the transformative potential of solidarity.

    Science.gov (United States)

    Harmon, Shawn H E; Mcmahon, Aisling

    2014-01-01

    Modern technologies and biomedicine ambitions have given rise to new models of medical research, including population biobanking. One example of biobanking is brain banking, which refers to the collection and storage of brain and spinal cord samples for research into neurological diseases. Obviously, brain banking involves taking brains and tissue from deceased people, a fact which complicates the role of recruiters and makes consent a poor tool for stakeholders. After contextualising brain banking and considering the public health issues at stake, this article explores the legal definitions and demands of, and actual processes around, consent in England/Wales/Northern Ireland and authorisation in Scotland, articulating and evaluating their conceptual and practical differences. It then argues for an expanded but improved operation of 'authorisation' in the brain banking (and broader biobanking) setting, adopting 'solidarity' as our foundation and the improvement of the 'public good' our objective.

  19. Auditory brain-stem evoked potentials in cat after kainic acid induced neuronal loss. I. Superior olivary complex.

    Science.gov (United States)

    Zaaroor, M; Starr, A

    1991-01-01

    Auditory brain-stem potentials (ABRs) were studied in cats for up to 45 days after kainic acid had been injected unilaterally or bilaterally into the superior olivary complex (SOC) to produce neuronal destruction while sparing fibers of passage and the terminals of axons of extrinsic origin connecting to SOC neurons. The components of the ABR in cat were labeled by their polarity at the vertex (P, for positive) and their order of appearance (the arabic numerals 1, 2, etc.). Component P1 can be further subdivided into 2 subcomponents labeled P1a and P1b. The correspondences we have assumed between the ABR components in cat and man are indicated by providing a Roman numeral designation for the human component in parentheses following the feline notation, e.g., P4 (V). With bilateral SOC destruction, there was a significant and marked attenuation of waves P2 (III), P3 (IV), P4 (V), P5 (VI), and the sustained potential shift (SPS) amounting to as much as 80% of preoperative values. Following unilateral SOC destruction the attenuation of many of these same ABR components, in response to stimulation of either ear, was up to 50%. No component of the ABR was totally abolished even when the SOC was lesioned 100% bilaterally. In unilaterally lesioned cats with extensive neuronal loss (greater than 75%) the latencies of the components beginning at P3 (IV) were delayed to stimulation of the ear ipsilateral to the injection site but not to stimulation of the ear contralateral to the injection. Binaural interaction components of the ABR were affected in proportion to the attenuation of the ABR. These results are compatible with multiple brain regions contributing to the generation of the components of the ABR beginning with P2 (III) and that components P3 (IV), P4 (V), and P5 (VI) and the sustained potential shift depend particularly on the integrity of the neurons of the SOC bilaterally. The neurons of the lateral subdivision (LSO) and the medial nucleus of the trapezoid body

  20. Risk indicators and potential risk factors for caries in 5-year-olds of different ethnic groups in Amsterdam.

    NARCIS (Netherlands)

    Verrips, G.H.; Frencken, J.E.; Kalsbeek, H.; Horst, G. ter; Filedt Kok-Weimar, T.L.

    1992-01-01

    The aim of this study was threefold: first, to assess the oral health of Turkish, Moroccan, Surinamese, Dutch and "other" 5-yr-old children living in Amsterdam; second, to identify risk indicators for caries, in addition to ethnicity; and third, to identify potential risk factors related to differen

  1. Developing alternative indices of reproductive potential for use in fisheries management : Case studies for stocks spanning an information gradient

    DEFF Research Database (Denmark)

    Marshall, C.T.; O'Brien, L.; Tomkiewicz, Jonna;

    2003-01-01

    sufficient data to reconstruct a time series of total eggproduction (TEP), whereas, the remaining stocks were limited to estimating proxies for stockreproductive potential. For some of the case studies the alternative indices explained a higheramount of recruitment variation than did SSB. Other case studies...

  2. Carbamazepine as indicator for potential short-term contamination of karst springs

    Science.gov (United States)

    Doummar, J.; Baierl, M.; Noedler, K.; Licha, T.; Sauter, M.; Geyer, T.

    2012-04-01

    Karst aquifers are complex systems which vulnerability is very difficult to assess mainly because of the duality of recharge processes and duality of flow. Recharge to a karst aquifer occurs as diffuse or concentrated (sinkholes and dolines). Moreover, karst aquifers are formed by an unsaturated zone comprising soil, epikarst and unsaturated rock matrix, and a saturated zone formed of highly permeable conduits and low permeability matrix storage. In the case of contamination of groundwater by wastewater effluent polluted water can be either transported rapidly and have short term major risk on spring water quality or infiltrate into fractured rock matrix and therefore have a long term effect on the water quality. In order to identify the risk of wastewater infiltrating into an aquifer, researches have focused to date on the identification of indicative wastewater markers. Carbamazepine (CBZ) was frequently detected in surface water as well as in effluents of sewage treatment plants, as less than 10% of carbamazepine are usually eliminated during sewage treatment. Moreover, CBZ is not attenuated in aquifers (Heberer, 2002), is unlikely degradable or adsorbed, and can be detected in groundwater (Clara et al., 2004). Therefore, CBZ is considered to be fairly persistent in groundwater (Tixier et al., 2003), and is consequently regarded as an effective wastewater marker. In this case study, the Jeita spring in Lebanon (spring discharge: 1-20 m3/s) was monitored and sampled for major ions and micro-pollutants following a combined precipitation/snowmelt events. A total of 28 samples (major ions and micro-pollutants) were taken over a total sampling time of 16 days at interval varying between 4 and 24 hours. Based on the variation with time of discharge and electrical conductivity (monitored every 20 minutes) as well as the concentrations of the major ions, a conceptual model showing the response of the aquifer compartments to the precipitation event was generated. A

  3. Electrical stimulation alleviates depressive-like behaviors of rats: investigation of brain targets and potential mechanisms

    OpenAIRE

    Lim, L.W.; Prickaerts, J.; Huguet, G; Kadar, E; Hartung, H; Sharp, T; Y. Temel

    2015-01-01

    Deep brain stimulation (DBS) is a promising therapy for patients with refractory depression. However, key questions remain with regard to which brain target(s) should be used for stimulation, and which mechanisms underlie the therapeutic effects. Here, we investigated the effect of DBS, with low- and high-frequency stimulation (LFS, HFS), in different brain regions (ventromedial prefrontal cortex, vmPFC; cingulate cortex, Cg; nucleus accumbens (NAc) core or shell; lateral habenula, LHb; and v...

  4. Toward FRP-Based Brain-Machine Interfaces-Single-Trial Classification of Fixation-Related Potentials.

    Science.gov (United States)

    Finke, Andrea; Essig, Kai; Marchioro, Giuseppe; Ritter, Helge

    2016-01-01

    The co-registration of eye tracking and electroencephalography provides a holistic measure of ongoing cognitive processes. Recently, fixation-related potentials have been introduced to quantify the neural activity in such bi-modal recordings. Fixation-related potentials are time-locked to fixation onsets, just like event-related potentials are locked to stimulus onsets. Compared to existing electroencephalography-based brain-machine interfaces that depend on visual stimuli, fixation-related potentials have the advantages that they can be used in free, unconstrained viewing conditions and can also be classified on a single-trial level. Thus, fixation-related potentials have the potential to allow for conceptually different brain-machine interfaces that directly interpret cortical activity related to the visual processing of specific objects. However, existing research has investigated fixation-related potentials only with very restricted and highly unnatural stimuli in simple search tasks while participant's body movements were restricted. We present a study where we relieved many of these restrictions while retaining some control by using a gaze-contingent visual search task. In our study, participants had to find a target object out of 12 complex and everyday objects presented on a screen while the electrical activity of the brain and eye movements were recorded simultaneously. Our results show that our proposed method for the classification of fixation-related potentials can clearly discriminate between fixations on relevant, non-relevant and background areas. Furthermore, we show that our classification approach generalizes not only to different test sets from the same participant, but also across participants. These results promise to open novel avenues for exploiting fixation-related potentials in electroencephalography-based brain-machine interfaces and thus providing a novel means for intuitive human-machine interaction.

  5. Toward FRP-Based Brain-Machine Interfaces-Single-Trial Classification of Fixation-Related Potentials.

    Directory of Open Access Journals (Sweden)

    Andrea Finke

    Full Text Available The co-registration of eye tracking and electroencephalography provides a holistic measure of ongoing cognitive processes. Recently, fixation-related potentials have been introduced to quantify the neural activity in such bi-modal recordings. Fixation-related potentials are time-locked to fixation onsets, just like event-related potentials are locked to stimulus onsets. Compared to existing electroencephalography-based brain-machine interfaces that depend on visual stimuli, fixation-related potentials have the advantages that they can be used in free, unconstrained viewing conditions and can also be classified on a single-trial level. Thus, fixation-related potentials have the potential to allow for conceptually different brain-machine interfaces that directly interpret cortical activity related to the visual processing of specific objects. However, existing research has investigated fixation-related potentials only with very restricted and highly unnatural stimuli in simple search tasks while participant's body movements were restricted. We present a study where we relieved many of these restrictions while retaining some control by using a gaze-contingent visual search task. In our study, participants had to find a target object out of 12 complex and everyday objects presented on a screen while the electrical activity of the brain and eye movements were recorded simultaneously. Our results show that our proposed method for the classification of fixation-related potentials can clearly discriminate between fixations on relevant, non-relevant and background areas. Furthermore, we show that our classification approach generalizes not only to different test sets from the same participant, but also across participants. These results promise to open novel avenues for exploiting fixation-related potentials in electroencephalography-based brain-machine interfaces and thus providing a novel means for intuitive human-machine interaction.

  6. Pathophysiology of Juvenile Traumatic Brain Injury: Role of Edema and a Potential Treatment

    OpenAIRE

    Adami, Arash

    2013-01-01

    Traumatic brain injury (TBI) is caused by an external force to the head, resulting in damage to the brain. TBI is especially common in children and young adults and is associated with long-term mortality and morbidity. Juveniles seem to be at increased risk of developing cerebral edema after TBI partly due to higher water content and developmental differences in the brain's response to injury. Aquaporin-4 (AQP4) is the most abundant water channel in the brain and plays a critical role in edem...

  7. Assessment of students’ health condition by indicators of adaptation potential, biological age and bio-energetic reserves of organism

    Directory of Open Access Journals (Sweden)

    Martyniuk O.V.

    2015-06-01

    Full Text Available Purpose: to assess students’ health condition by indicators of adaptation potential, biological age and express-assessment. Material: in the research 47 first and second year girl students participated, who belonged to main health group. Results: we distributed the girl students into three groups: 14.89% of them were included in group with “safe” health condition; 34.04% - in group of “third state”; 51.06% were related to group with “ dangerous” health condition. We established that dangerous level was characterized by energy potential of below middle and low level. It is accompanied by accelerated processes of organism’s age destructions and tension of regulation mechanisms. Conclusions: the received results permit to further develop and generalize the data of students’ health’s assessment by indicators of adaptation potentials, biological age and physical health’s condition.

  8. Dogs Cannot Bark: Event-Related Brain Responses to True and False Negated Statements as Indicators of Higher-Order Conscious Processing

    OpenAIRE

    Cornelia Herbert; Andrea Kübler

    2011-01-01

    The present study investigated event-related brain potentials elicited by true and false negated statements to evaluate if discrimination of the truth value of negated information relies on conscious processing and requires higher-order cognitive processing in healthy subjects across different levels of stimulus complexity. The stimulus material consisted of true and false negated sentences (sentence level) and prime-target expressions (word level). Stimuli were presented acoustically and no ...

  9. A Brain Computer Interface for Robust Wheelchair Control Application Based on Pseudorandom Code Modulated Visual Evoked Potential

    DEFF Research Database (Denmark)

    Mohebbi, Ali; Engelsholm, Signe K.D.; Puthusserypady, Sadasivan;

    2015-01-01

    In this pilot study, a novel and minimalistic Brain Computer Interface (BCI) based wheelchair control application was developed. The system was based on pseudorandom code modulated Visual Evoked Potentials (c-VEPs). The visual stimuli in the scheme were generated based on the Gold code...

  10. The effect of repetition of infrequent familiar and unfamiliar visual patterns on components of the event-related brain potential.

    NARCIS (Netherlands)

    A. Kok; H. de Looren de Jong

    1980-01-01

    Examined changes in the waveforms of the event-related brain potential (ERP) during repeated presentations of infrequent-familiar and infrequent-unfamiliar visual patterns; Ss were 12 male university students. The EEG waveforms were averaged separately for each presentation of the 2 types of stimuli

  11. Dogs cannot bark: event-related brain responses to true and false negated statements as indicators of higher-order conscious processing.

    Science.gov (United States)

    Herbert, Cornelia; Kübler, Andrea

    2011-01-01

    The present study investigated event-related brain potentials elicited by true and false negated statements to evaluate if discrimination of the truth value of negated information relies on conscious processing and requires higher-order cognitive processing in healthy subjects across different levels of stimulus complexity. The stimulus material consisted of true and false negated sentences (sentence level) and prime-target expressions (word level). Stimuli were presented acoustically and no overt behavioral response of the participants was required. Event-related brain potentials to target words preceded by true and false negated expressions were analyzed both within group and at the single subject level. Across the different processing conditions (word pairs and sentences), target words elicited a frontal negativity and a late positivity in the time window from 600-1000 msec post target word onset. Amplitudes of both brain potentials varied as a function of the truth value of the negated expressions. Results were confirmed at the single-subject level. In sum, our results support recent suggestions according to which evaluation of the truth value of a negated expression is a time- and cognitively demanding process that cannot be solved automatically, and thus requires conscious processing. Our paradigm provides insight into higher-order processing related to language comprehension and reasoning in healthy subjects. Future studies are needed to evaluate if our paradigm also proves sensitive for the detection of consciousness in non-responsive patients. PMID:22022414

  12. Dogs cannot bark: event-related brain responses to true and false negated statements as indicators of higher-order conscious processing.

    Directory of Open Access Journals (Sweden)

    Cornelia Herbert

    Full Text Available The present study investigated event-related brain potentials elicited by true and false negated statements to evaluate if discrimination of the truth value of negated information relies on conscious processing and requires higher-order cognitive processing in healthy subjects across different levels of stimulus complexity. The stimulus material consisted of true and false negated sentences (sentence level and prime-target expressions (word level. Stimuli were presented acoustically and no overt behavioral response of the participants was required. Event-related brain potentials to target words preceded by true and false negated expressions were analyzed both within group and at the single subject level. Across the different processing conditions (word pairs and sentences, target words elicited a frontal negativity and a late positivity in the time window from 600-1000 msec post target word onset. Amplitudes of both brain potentials varied as a function of the truth value of the negated expressions. Results were confirmed at the single-subject level. In sum, our results support recent suggestions according to which evaluation of the truth value of a negated expression is a time- and cognitively demanding process that cannot be solved automatically, and thus requires conscious processing. Our paradigm provides insight into higher-order processing related to language comprehension and reasoning in healthy subjects. Future studies are needed to evaluate if our paradigm also proves sensitive for the detection of consciousness in non-responsive patients.

  13. Dogs cannot bark: event-related brain responses to true and false negated statements as indicators of higher-order conscious processing.

    Science.gov (United States)

    Herbert, Cornelia; Kübler, Andrea

    2011-01-01

    The present study investigated event-related brain potentials elicited by true and false negated statements to evaluate if discrimination of the truth value of negated information relies on conscious processing and requires higher-order cognitive processing in healthy subjects across different levels of stimulus complexity. The stimulus material consisted of true and false negated sentences (sentence level) and prime-target expressions (word level). Stimuli were presented acoustically and no overt behavioral response of the participants was required. Event-related brain potentials to target words preceded by true and false negated expressions were analyzed both within group and at the single subject level. Across the different processing conditions (word pairs and sentences), target words elicited a frontal negativity and a late positivity in the time window from 600-1000 msec post target word onset. Amplitudes of both brain potentials varied as a function of the truth value of the negated expressions. Results were confirmed at the single-subject level. In sum, our results support recent suggestions according to which evaluation of the truth value of a negated expression is a time- and cognitively demanding process that cannot be solved automatically, and thus requires conscious processing. Our paradigm provides insight into higher-order processing related to language comprehension and reasoning in healthy subjects. Future studies are needed to evaluate if our paradigm also proves sensitive for the detection of consciousness in non-responsive patients.

  14. Stimulus Specificity of Brain-Computer Interfaces Based on Code Modulation Visual Evoked Potentials.

    Directory of Open Access Journals (Sweden)

    Qingguo Wei

    Full Text Available A brain-computer interface (BCI based on code modulated visual evoked potentials (c-VEP is among the fastest BCIs that have ever been reported, but it has not yet been given a thorough study. In this study, a pseudorandom binary M sequence and its time lag sequences are utilized for modulation of different stimuli and template matching is adopted as the method for target recognition. Five experiments were devised to investigate the effect of stimulus specificity on target recognition and we made an effort to find the optimal stimulus parameters for size, color and proximity of the stimuli, length of modulation sequence and its lag between two adjacent stimuli. By changing the values of these parameters and measuring classification accuracy of the c-VEP BCI, an optimal value of each parameter can be attained. Experimental results of ten subjects showed that stimulus size of visual angle 3.8°, white, spatial proximity of visual angle 4.8° center to center apart, modulation sequence of length 63 bits and the lag of 4 bits between adjacent stimuli yield individually superior performance. These findings provide a basis for determining stimulus presentation of a high-performance c-VEP based BCI system.

  15. How children process over-regularizations: evidence from event-related brain potentials.

    Science.gov (United States)

    Clahsen, Harald; Lück, Monika; Hahne, Anja

    2007-08-01

    This study examines the mental processes involved in children's on-line recognition of inflected word forms using event-related potentials (ERPs). Sixty children in three age groups (20 six- to seven-year-olds, 20 eight- to nine-year-olds, 20 eleven- to twelve-year-olds) and 23 adults (tested in a previous study) listened to sentences containing correct or incorrect German noun plural forms. In the two older child groups, as well as in the adult group, over-regularized plural forms elicited brain responses that are characteristic of combinatorial (grammatical) violations. We also found that ERP components associated with language processing change from child to adult with respect to their onsets and their topography. The ERP violation effects obtained for over-regularizations suggest that children (aged eight years and above) and adults employ morphological computation for processing purposes, consistent with dual-mechanism models of inflection. The observed differences between children's and adults' ERP responses are argued to result from children's smaller lexicons and from slower and less efficient processing.

  16. Time-Shift Correlation Algorithm for P300 Event Related Potential Brain-Computer Interface Implementation

    Science.gov (United States)

    Liu, Ju-Chi; Chou, Hung-Chyun; Chen, Chien-Hsiu; Lin, Yi-Tseng

    2016-01-01

    A high efficient time-shift correlation algorithm was proposed to deal with the peak time uncertainty of P300 evoked potential for a P300-based brain-computer interface (BCI). The time-shift correlation series data were collected as the input nodes of an artificial neural network (ANN), and the classification of four LED visual stimuli was selected as the output node. Two operating modes, including fast-recognition mode (FM) and accuracy-recognition mode (AM), were realized. The proposed BCI system was implemented on an embedded system for commanding an adult-size humanoid robot to evaluate the performance from investigating the ground truth trajectories of the humanoid robot. When the humanoid robot walked in a spacious area, the FM was used to control the robot with a higher information transfer rate (ITR). When the robot walked in a crowded area, the AM was used for high accuracy of recognition to reduce the risk of collision. The experimental results showed that, in 100 trials, the accuracy rate of FM was 87.8% and the average ITR was 52.73 bits/min. In addition, the accuracy rate was improved to 92% for the AM, and the average ITR decreased to 31.27 bits/min. due to strict recognition constraints.

  17. Dispositional mindfulness and semantic integration of emotional words: Evidence from event-related brain potentials.

    Science.gov (United States)

    Dorjee, Dusana; Lally, Níall; Darrall-Rew, Jonathan; Thierry, Guillaume

    2015-08-01

    Initial research shows that mindfulness training can enhance attention and modulate the affective response. However, links between mindfulness and language processing remain virtually unexplored despite the prominent role of overt and silent negative ruminative speech in depressive and anxiety-related symptomatology. Here, we measured dispositional mindfulness and recorded participants' event-related brain potential responses to positive and negative target words preceded by words congruent or incongruent with the targets in terms of semantic relatedness and emotional valence. While the low mindfulness group showed similar N400 effect pattern for positive and negative targets, high dispositional mindfulness was associated with larger N400 effect to negative targets. This result suggests that negative meanings are less readily accessible in people with high dispositional mindfulness. Furthermore, high dispositional mindfulness was associated with reduced P600 amplitudes to emotional words, suggesting less post-analysis and attentional effort which possibly relates to a lower inclination to ruminate. Overall, these findings provide initial evidence on associations between modifications in language systems and mindfulness.

  18. Instrumentation to record evoked potentials for closed-loop control of deep brain stimulation.

    Science.gov (United States)

    Kent, Alexander R; Grill, Warren M

    2011-01-01

    Closed-loop deep brain stimulation (DBS) systems offer promise in relieving the clinical burden of stimulus parameter selection and improving treatment outcomes. In such a system, a feedback signal is used to adjust automatically stimulation parameters and optimize the efficacy of stimulation. We explored the feasibility of recording electrically evoked compound action potentials (ECAPs) during DBS for use as a feedback control signal. A novel instrumentation system was developed to suppress the stimulus artifact and amplify the small magnitude, short latency ECAP response during DBS with clinically relevant parameters. In vitro testing demonstrated the capabilities to increase the gain by a factor of 1,000× over a conventional amplifier without saturation, reduce distortion of mock ECAP signals, and make high fidelity recordings of mock ECAPs at latencies of only 0.5 ms following DBS pulses of 50 to 100 μs duration. Subsequently, the instrumentation was used to make in vivo recordings of ECAPs during thalamic DBS in cats, without contamination by the stimulus artifact. The signal characteristics were similar across three experiments, suggesting common neural activation patterns. The ECAP recordings enabled with this novel instrumentation may provide insight into the type and spatial extent of neural elements activated during DBS, and could serve as feedback control signals for closed-loop systems. PMID:22255894

  19. Effects of incense on brain function: evaluation using electroencephalograms and event-related potentials.

    Science.gov (United States)

    Iijima, Mutsumi; Osawa, Mikio; Nishitani, Nobuyuki; Iwata, Makoto

    2009-01-01

    To evaluate the effect of the odor of incense on brain activity, electroencephalograms (EEGs) and event-related potentials (ERPs) in a push/wait paradigm were recorded in 10 healthy adults (aged 23-39 years) with normal olfactory function. EEG was recorded from 21 electrodes on the scalp, according to the International 10-20 system, and EEG power spectra were calculated by fast Fourier transform for 3 min before and during odor presentation. ERPs were recorded from 15 electrodes on the scalp before, during and after exposure to incense with intervals of 10 min. In a push/wait paradigm, two Japanese words, 'push' as the go stimulus and 'wait' as the no-go stimulus, appeared randomly on a CRT screen with equal probability. The subjects were instructed to push a button whenever the 'push' signal appeared. Fast alpha activity (10-13 Hz) increased significantly in bilateral posterior regions during incense exposure compared to that during rose oil exposure. The peak amplitudes of no-go P3 at Fz and Cz were significantly greater during incense inhalation. The latencies of go P3 and no-go P3, and the amplitude and latencies of no-go N2 did not change by exposure to the odors of both incense, rose and odorless air. These results suggest that the odor of incense may enhance cortical activities and the function of inhibitory processing of motor response.

  20. Time-Shift Correlation Algorithm for P300 Event Related Potential Brain-Computer Interface Implementation.

    Science.gov (United States)

    Liu, Ju-Chi; Chou, Hung-Chyun; Chen, Chien-Hsiu; Lin, Yi-Tseng; Kuo, Chung-Hsien

    2016-01-01

    A high efficient time-shift correlation algorithm was proposed to deal with the peak time uncertainty of P300 evoked potential for a P300-based brain-computer interface (BCI). The time-shift correlation series data were collected as the input nodes of an artificial neural network (ANN), and the classification of four LED visual stimuli was selected as the output node. Two operating modes, including fast-recognition mode (FM) and accuracy-recognition mode (AM), were realized. The proposed BCI system was implemented on an embedded system for commanding an adult-size humanoid robot to evaluate the performance from investigating the ground truth trajectories of the humanoid robot. When the humanoid robot walked in a spacious area, the FM was used to control the robot with a higher information transfer rate (ITR). When the robot walked in a crowded area, the AM was used for high accuracy of recognition to reduce the risk of collision. The experimental results showed that, in 100 trials, the accuracy rate of FM was 87.8% and the average ITR was 52.73 bits/min. In addition, the accuracy rate was improved to 92% for the AM, and the average ITR decreased to 31.27 bits/min. due to strict recognition constraints.

  1. Time-Shift Correlation Algorithm for P300 Event Related Potential Brain-Computer Interface Implementation

    Directory of Open Access Journals (Sweden)

    Ju-Chi Liu

    2016-01-01

    Full Text Available A high efficient time-shift correlation algorithm was proposed to deal with the peak time uncertainty of P300 evoked potential for a P300-based brain-computer interface (BCI. The time-shift correlation series data were collected as the input nodes of an artificial neural network (ANN, and the classification of four LED visual stimuli was selected as the output node. Two operating modes, including fast-recognition mode (FM and accuracy-recognition mode (AM, were realized. The proposed BCI system was implemented on an embedded system for commanding an adult-size humanoid robot to evaluate the performance from investigating the ground truth trajectories of the humanoid robot. When the humanoid robot walked in a spacious area, the FM was used to control the robot with a higher information transfer rate (ITR. When the robot walked in a crowded area, the AM was used for high accuracy of recognition to reduce the risk of collision. The experimental results showed that, in 100 trials, the accuracy rate of FM was 87.8% and the average ITR was 52.73 bits/min. In addition, the accuracy rate was improved to 92% for the AM, and the average ITR decreased to 31.27 bits/min. due to strict recognition constraints.

  2. Parafoveal processing in reading Chinese sentences: Evidence from event-related brain potentials.

    Science.gov (United States)

    Li, Nan; Niefind, Florian; Wang, Suiping; Sommer, Werner; Dimigen, Olaf

    2015-10-01

    Natural reading involves the preprocessing of upcoming words, resulting in shorter fixations on words visible in the parafovea during preceding fixations. While this preview benefit is established in behavior, its brain-electric correlates have only recently been investigated. Using fixation-related potentials, an attenuation of the occipitotemporal N1 component for words that were parafoveally visible during preceding fixations has been demonstrated. In contrast, another study, using an RSVP paradigm with parafoveal flanker words, observed no such general preview benefit in ERPs, but instead reported N400 effects triggered by semantically incongruous parafoveal words. To follow up on these discrepant findings and to extend them to a nonalphabetic writing system, we conducted two ERP experiments with Chinese readers using the RSVP-with-flankers paradigm and rigorous fixation control via eye tracking. We replicate robust parafoveal N400 semantic congruency effects in Chinese participants. Additionally, we found that, once a word was directly looked at, words after a valid preview elicited a smaller N1 and a weaker N400 than those after an invalid preview. Results underline the importance of considering parafoveal vision in ERP studies on reading. PMID:26289548

  3. Subject combination and electrode selection in cooperative brain-computer interface based on event related potentials.

    Science.gov (United States)

    Cecotti, Hubert; Rivet, Bertrand

    2014-01-01

    New paradigms are required in Brain-Computer Interface (BCI) systems for the needs and expectations of healthy people. To solve this issue, we explore the emerging field of cooperative BCIs, which involves several users in a single BCI system. Contrary to classical BCIs that are dependent on the unique subject's will, cooperative BCIs are used for problem solving tasks where several people shall be engaged by sharing a common goal. Similarly as combining trials over time improves performance, combining trials across subjects can significantly improve performance compared with when only a single user is involved. Yet, cooperative BCIs may only be used in particular settings, and new paradigms must be proposed to efficiently use this approach. The possible benefits of using several subjects are addressed, and compared with current single-subject BCI paradigms. To show the advantages of a cooperative BCI, we evaluate the performance of combining decisions across subjects with data from an event-related potentials (ERP) based experiment where each subject observed the same sequence of visual stimuli. Furthermore, we show that it is possible to achieve a mean AUC superior to 0.95 with 10 subjects and 3 electrodes on each subject, or with 4 subjects and 6 electrodes on each subject. Several emerging challenges and possible applications are proposed to highlight how cooperative BCIs could be efficiently used with current technologies and leverage BCI applications. PMID:24961765

  4. Subject Combination and Electrode Selection in Cooperative Brain-Computer Interface Based on Event Related Potentials

    Directory of Open Access Journals (Sweden)

    Hubert Cecotti

    2014-04-01

    Full Text Available New paradigms are required in Brain-Computer Interface (BCI systems for the needs and expectations of healthy people. To solve this issue, we explore the emerging field of cooperative BCIs, which involves several users in a single BCI system. Contrary to classical BCIs that are dependent on the unique subject’s will, cooperative BCIs are used for problem solving tasks where several people shall be engaged by sharing a common goal. Similarly as combining trials over time improves performance, combining trials across subjects can significantly improve performance compared with when only a single user is involved. Yet, cooperative BCIs may only be used in particular settings, and new paradigms must be proposed to efficiently use this approach. The possible benefits of using several subjects are addressed, and compared with current single-subject BCI paradigms. To show the advantages of a cooperative BCI, we evaluate the performance of combining decisions across subjects with data from an event-related potentials (ERP based experiment where each subject observed the same sequence of visual stimuli. Furthermore, we show that it is possible to achieve a mean AUC superior to 0.95 with 10 subjects and 3 electrodes on each subject, or with 4 subjects and 6 electrodes on each subject. Several emerging challenges and possible applications are proposed to highlight how cooperative BCIs could be efficiently used with current technologies and leverage BCI applications.

  5. Abnormal error monitoring in math-anxious individuals: evidence from error-related brain potentials.

    Science.gov (United States)

    Suárez-Pellicioni, Macarena; Núñez-Peña, María Isabel; Colomé, Angels

    2013-01-01

    This study used event-related brain potentials to investigate whether math anxiety is related to abnormal error monitoring processing. Seventeen high math-anxious (HMA) and seventeen low math-anxious (LMA) individuals were presented with a numerical and a classical Stroop task. Groups did not differ in terms of trait or state anxiety. We found enhanced error-related negativity (ERN) in the HMA group when subjects committed an error on the numerical Stroop task, but not on the classical Stroop task. Groups did not differ in terms of the correct-related negativity component (CRN), the error positivity component (Pe), classical behavioral measures or post-error measures. The amplitude of the ERN was negatively related to participants' math anxiety scores, showing a more negative amplitude as the score increased. Moreover, using standardized low resolution electromagnetic tomography (sLORETA) we found greater activation of the insula in errors on a numerical task as compared to errors in a non-numerical task only for the HMA group. The results were interpreted according to the motivational significance theory of the ERN.

  6. Abnormal error monitoring in math-anxious individuals: evidence from error-related brain potentials.

    Directory of Open Access Journals (Sweden)

    Macarena Suárez-Pellicioni

    Full Text Available This study used event-related brain potentials to investigate whether math anxiety is related to abnormal error monitoring processing. Seventeen high math-anxious (HMA and seventeen low math-anxious (LMA individuals were presented with a numerical and a classical Stroop task. Groups did not differ in terms of trait or state anxiety. We found enhanced error-related negativity (ERN in the HMA group when subjects committed an error on the numerical Stroop task, but not on the classical Stroop task. Groups did not differ in terms of the correct-related negativity component (CRN, the error positivity component (Pe, classical behavioral measures or post-error measures. The amplitude of the ERN was negatively related to participants' math anxiety scores, showing a more negative amplitude as the score increased. Moreover, using standardized low resolution electromagnetic tomography (sLORETA we found greater activation of the insula in errors on a numerical task as compared to errors in a non-numerical task only for the HMA group. The results were interpreted according to the motivational significance theory of the ERN.

  7. Brain catalase mediates potentiation of social recognition memory produced by ethanol in mice.

    Science.gov (United States)

    Manrique, Héctor M; Miquel, Marta; Aragon, Carlos M G

    2005-09-01

    The involvement of catalase in ethanol-induced locomotion has been clearly proven. However, studies addressing the role of this enzyme in the effects that ethanol exerts on memory are lacking. In the present study, the social recognition test (SRT) was used to evaluate ethanol effects on memory. In this test, the reduction in investigation time of a juvenile conspecific, when this social stimulus is presented for the second time, is considered a reliable index of memory. Exploration ratios (ER) were calculated to evaluate the recognition capacity of mice. Ethanol (0.0, 0.5, 1.0 or 1.5g/kg, i.p.) was administered immediately after the first juvenile presentation, and 2h later the juvenile was re-exposed to the adult. Additionally, adult mice received aminotriazole (AT) or sodium azide (two catalase inhibitors) 5h or 30 min before juvenile presentation, respectively. Ethanol (1.0 and 1.5g/kg) was able to reduce ER, indicating an improving effect on memory. This improvement was prevented by either AT or sodium azide pre-treatment. However, neither AT nor sodium azide attenuated the memory-enhancing capacity of NMDA or nicotine, suggesting a specific interaction between catalase inhibitors and ethanol in their effects on memory. The present results suggest that brain catalase activity could mediate the memory-enhancing capacity of ethanol and add further support to the idea that this enzyme mediates some of the psychopharmacological effects produced by ethanol. PMID:16102377

  8. Long term, stable brain machine interface performance using local field potentials and multiunit spikes

    Science.gov (United States)

    Flint, Robert D.; Wright, Zachary A.; Scheid, Michael R.; Slutzky, Marc W.

    2013-10-01

    Objective. Brain machine interfaces (BMIs) have the potential to restore movement to people with paralysis. However, a clinically-viable BMI must enable consistently accurate control over time spans ranging from years to decades, which has not yet been demonstrated. Most BMIs that use single-unit spikes as inputs will experience degraded performance over time without frequent decoder re-training. Two other signals, local field potentials (LFPs) and multi-unit spikes (MSPs), may offer greater reliability over long periods and better performance stability than single-unit spikes. Here, we demonstrate that LFPs can be used in a biomimetic BMI to control a computer cursor. Approach. We implanted two rhesus macaques with intracortical microelectrodes in primary motor cortex. We recorded LFP and MSP signals from the monkeys while they performed a continuous reaching task, moving a cursor to randomly-placed targets on a computer screen. We then used the LFP and MSP signals to construct biomimetic decoders for control of the cursor. Main results. Both monkeys achieved high-performance, continuous control that remained stable or improved over nearly 12 months using an LFP decoder that was not retrained or adapted. In parallel, the monkeys used MSPs to control a BMI without retraining or adaptation and had similar or better performance, and that predominantly remained stable over more than six months. In contrast to their stable online control, both LFP and MSP signals showed substantial variability when used offline to predict hand movements. Significance. Our results suggest that the monkeys were able to stabilize the relationship between neural activity and cursor movement during online BMI control, despite variability in the relationship between neural activity and hand movements.

  9. Different Brain Wave Patterns and Cortical Control Abilities in Relation to Different Creative Potentials

    Science.gov (United States)

    Li, Ying-Han; Tseng, Chao-Yuan; Tsai, Arthur Chih-Hsin; Huang, Andrew Chih-Wei; Lin, Wei-Lun

    2016-01-01

    Contemporary understanding of brain functions provides a way to probe into the mystery of creativity. However, the prior evidence regarding the relationship between creativity and brain wave patterns reveals inconsistent conclusions. One possible reason might be that the means of selecting creative individuals in the past has varied in each study.…

  10. Towards an optimization of stimulus parameters for brain-computer interfaces based on steady state visual evoked potentials.

    Directory of Open Access Journals (Sweden)

    Anna Duszyk

    Full Text Available Efforts to construct an effective brain-computer interface (BCI system based on Steady State Visual Evoked Potentials (SSVEP commonly focus on sophisticated mathematical methods for data analysis. The role of different stimulus features in evoking strong SSVEP is less often considered and the knowledge on the optimal stimulus properties is still fragmentary. The goal of this study was to provide insight into the influence of stimulus characteristics on the magnitude of SSVEP response. Five stimuli parameters were tested: size, distance, colour, shape, and presence of a fixation point in the middle of each flickering field. The stimuli were presented on four squares on LCD screen, with each square highlighted by LEDs flickering with different frequencies. Brighter colours and larger dimensions of flickering fields resulted in a significantly stronger SSVEP response. The distance between stimulation fields and the presence or absence of the fixation point had no significant effect on the response. Contrary to a popular belief, these results suggest that absence of the fixation point does not reduce the magnitude of SSVEP response. However, some parameters of the stimuli such as colour and the size of the flickering field play an important role in evoking SSVEP response, which indicates that stimuli rendering is an important factor in building effective SSVEP based BCI systems.

  11. Aggregation of sparse linear discriminant analyses for event-related potential classification in brain-computer interface.

    Science.gov (United States)

    Zhang, Yu; Zhou, Guoxu; Jin, Jing; Zhao, Qibin; Wang, Xingyu; Cichocki, Andrzej

    2014-02-01

    Two main issues for event-related potential (ERP) classification in brain-computer interface (BCI) application are curse-of-dimensionality and bias-variance tradeoff, which may deteriorate classification performance, especially with insufficient training samples resulted from limited calibration time. This study introduces an aggregation of sparse linear discriminant analyses (ASLDA) to overcome these problems. In the ASLDA, multiple sparse discriminant vectors are learned from differently l1-regularized least-squares regressions by exploiting the equivalence between LDA and least-squares regression, and are subsequently aggregated to form an ensemble classifier, which could not only implement automatic feature selection for dimensionality reduction to alleviate curse-of-dimensionality, but also decrease the variance to improve generalization capacity for new test samples. Extensive investigation and comparison are carried out among the ASLDA, the ordinary LDA and other competing ERP classification algorithms, based on different three ERP datasets. Experimental results indicate that the ASLDA yields better overall performance for single-trial ERP classification when insufficient training samples are available. This suggests the proposed ASLDA is promising for ERP classification in small sample size scenario to improve the practicability of BCI. PMID:24344691

  12. Potentials for Indication of Potentially Harmful Toxic Algal Blooms Using PROBA1-CHRIS Hyperspectral Imagery- A Case Study in Burkina Faso

    Science.gov (United States)

    Beiermann, Timo

    2010-12-01

    Toxic algal blooms are an issue affecting water quality and can cause harmful health impacts. The aim of the conducted case study is to assess such blooms by chlorophyll a and phycocyanin detection as indicators of the occurrence. Using demonstrated single reflectance ratio algorithms published as in [7] and processed with provided tools for hyperspectral Proba1-CHRIS imagery in a study site including Loumbila reservoir near Ouagadougou, capital of Burkina Faso to investigate potentials of this approach.

  13. Potential brain language reorganization in a boy with refractory epilepsy; an fNIRS–EEG and fMRI comparison

    Directory of Open Access Journals (Sweden)

    Phetsamone Vannasing

    2016-01-01

    Full Text Available As part of a presurgical investigation for a resection of a tumor located in the left temporal brain region, we evaluated pre- and postsurgical language lateralization in a right-handed boy with refractory epilepsy. In this study, we compared functional near infrared spectroscopy (fNIRS results obtained while the participant performed expressive and receptive language tasks with those obtained using functional magnetic resonance imaging (fMRI. This case study illustrates the potential for NIRS to contribute favorably to the localization of language functions in children with epilepsy and cognitive or behavioral problems and its potential advantages over fMRI in presurgical assessment. Moreover, it suggests that fNIRS is sensitive in localizing an atypical language network or potential brain reorganization related to epilepsy in young patients.

  14. Advancing the detection of steady-state visual evoked potentials in brain-computer interfaces

    Science.gov (United States)

    Abu-Alqumsan, Mohammad; Peer, Angelika

    2016-06-01

    Objective. Spatial filtering has proved to be a powerful pre-processing step in detection of steady-state visual evoked potentials and boosted typical detection rates both in offline analysis and online SSVEP-based brain-computer interface applications. State-of-the-art detection methods and the spatial filters used thereby share many common foundations as they all build upon the second order statistics of the acquired Electroencephalographic (EEG) data, that is, its spatial autocovariance and cross-covariance with what is assumed to be a pure SSVEP response. The present study aims at highlighting the similarities and differences between these methods. Approach. We consider the canonical correlation analysis (CCA) method as a basis for the theoretical and empirical (with real EEG data) analysis of the state-of-the-art detection methods and the spatial filters used thereby. We build upon the findings of this analysis and prior research and propose a new detection method (CVARS) that combines the power of the canonical variates and that of the autoregressive spectral analysis in estimating the signal and noise power levels. Main results. We found that the multivariate synchronization index method and the maximum contrast combination method are variations of the CCA method. All three methods were found to provide relatively unreliable detections in low signal-to-noise ratio (SNR) regimes. CVARS and the minimum energy combination methods were found to provide better estimates for different SNR levels. Significance. Our theoretical and empirical results demonstrate that the proposed CVARS method outperforms other state-of-the-art detection methods when used in an unsupervised fashion. Furthermore, when used in a supervised fashion, a linear classifier learned from a short training session is able to estimate the hidden user intention, including the idle state (when the user is not attending to any stimulus), rapidly, accurately and reliably.

  15. Performance Enhancement at the Cost of Potential Brain Plasticity: Neural Ramifications of Nootropic Drugs in the Healthy Developing Brain

    OpenAIRE

    Urban, Kimberly R.; Wen-Jun eGao

    2014-01-01

    Cognitive enhancement is perhaps one of the most intriguing and controversial topics in neuroscience today. Currently, the main classes of drugs used as potential cognitive enhancers include psychostimulants (methylphenidate, amphetamine), but wakefulness-promoting agents (modafinil) and glutamate activators (ampakine) are also frequently used. Pharmacologically, substances that enhance the components of the memory/learning circuits - dopamine, glutamate (neuronal excitation), and/or norepine...

  16. Tic related local field potentials in the thalamus and the effect of deep brain stimulation in Tourette syndrome : Report of three cases

    NARCIS (Netherlands)

    Bour, L. J.; Ackermans, L.; Foncke, E. M. J.; Cath, D.; van der Linden, C.; Vandewalle, V. Visser; Tijssen, M. A.

    2015-01-01

    Objective: Three patients with intractable Tourette syndrome (TS) underwent thalamic deep brain stimulation (DBS). To investigate the role of thalamic electrical activity in tic generation, local field potentials (LFP), EEG and EMG simultaneously were recorded. Methods: Event related potentials and

  17. Chronic P-glycoprotein inhibition increases the brain concentration of escitalopram: potential implications for treating depression.

    Science.gov (United States)

    O'Brien, Fionn E; Moloney, Gerard M; Scott, Karen A; O'Connor, Richard M; Clarke, Gerard; Dinan, Timothy G; Griffin, Brendan T; Cryan, John F

    2015-12-01

    Recent preclinical studies have revealed a functionally important role for the drug efflux pump P-glycoprotein (P-gp) at the blood-brain barrier in limiting brain levels and thus antidepressant-like activity of certain antidepressant drugs. Specifically, acute administration of P-gp inhibitors, such as verapamil and cyclosporin A (CsA), has been shown to augment brain concentrations and functional activity of the antidepressant escitalopram in rodents. However, depression is a chronic disorder and current treatments require prolonged administration to elicit their full therapeutic effect. Thus, it is important to investigate whether acute findings in relation to P-gp inhibition translate to chronic paradigms. To this end, the present study investigates whether chronic treatment with the P-gp inhibitor verapamil and the antidepressant escitalopram results in enhanced brain distribution and antidepressant-like effects of escitalopram. Verapamil (10 mg·kg(-1) i.p.) and escitalopram (0.1 mg·kg(-1) i.p.) were administered once daily for 22 days. On the final day of treatment, brain regions and plasma were collected for analysis of cortical and plasma escitalopram concentrations, and to determine the hippocampal expression of genes previously reported to be altered by chronic antidepressant treatment. Verapamil treatment resulted in a greater than twofold increase in brain levels of escitalopram, without altering plasma levels. Neither gene expression analysis nor behavioral testing revealed an augmentation of responses to escitalopram treatment due to verapamil administration. Taken together, these data demonstrate for the first time that P-gp inhibition can yield elevated brain concentrations of an antidepressant after chronic treatment. The functional relevance of these increased brain levels requires further elaboration. PMID:27022464

  18. Identification and analysis of signaling networks potentially involved in breast carcinoma metastasis to the brain.

    Directory of Open Access Journals (Sweden)

    Feng Li

    Full Text Available Brain is a common site of breast cancer metastasis associated with significant neurologic morbidity, decreased quality of life, and greatly shortened survival. However, the molecular and cellular mechanisms underpinning brain colonization by breast carcinoma cells are poorly understood. Here, we used 2D-DIGE (Difference in Gel Electrophoresis proteomic analysis followed by LC-tandem mass spectrometry to identify the proteins differentially expressed in brain-targeting breast carcinoma cells (MB231-Br compared with parental MDA-MB-231 cell line. Between the two cell lines, we identified 12 proteins consistently exhibiting greater than 2-fold (p<0.05 difference in expression, which were associated by the Ingenuity Pathway Analysis (IPA with two major signaling networks involving TNFα/TGFβ-, NFκB-, HSP-70-, TP53-, and IFNγ-associated pathways. Remarkably, highly related networks were revealed by the IPA analysis of a list of 19 brain-metastasis-associated proteins identified recently by the group of Dr. A. Sierra using MDA-MB-435-based experimental system (Martin et al., J Proteome Res 2008 7:908-20, or a 17-gene classifier associated with breast cancer brain relapse reported by the group of Dr. J. Massague based on a microarray analysis of clinically annotated breast tumors from 368 patients (Bos et al., Nature 2009 459: 1005-9. These findings, showing that different experimental systems and approaches (2D-DIGE proteomics used on brain targeting cell lines or gene expression analysis of patient samples with documented brain relapse yield highly related signaling networks, suggest strongly that these signaling networks could be essential for a successful colonization of the brain by metastatic breast carcinoma cells.

  19. Performance enhancement at the cost of potential brain plasticity: neural ramifications of nootropic drugs in the healthy developing brain

    OpenAIRE

    Urban, Kimberly R.; Gao, Wen-Jun

    2014-01-01

    Cognitive enhancement is perhaps one of the most intriguing and controversial topics in neuroscience today. Currently, the main classes of drugs used as potential cognitive enhancers include psychostimulants (methylphenidate (MPH), amphetamine), but wakefulness-promoting agents (modafinil) and glutamate activators (ampakine) are also frequently used. Pharmacologically, substances that enhance the components of the memory/learning circuits—dopamine, glutamate (neuronal excitation), and/or nore...

  20. AN in vitro evaluation of a carmustine-loaded Nano-co-Plex for potential magnetic-targeted intranasal delivery to the brain.

    Science.gov (United States)

    Akilo, Olufemi D; Choonara, Yahya E; Strydom, André M; du Toit, Lisa C; Kumar, Pradeep; Modi, Girish; Pillay, Viness

    2016-03-16

    Targeted delivery of carmustine (BCNU), an efficient brain tumor therapeutic, has been challenged with bioavailability issues due to the Blood Brain Barrier (BBB). The currently effective delivery approach is by implants at the site of the tumor, but this is highly invasive. The intranasal route, which is non-invasive and bypasses the BBB, may be alternative route for delivering BCNU to the brain. In this work, polyvinyl alcohol/polyethyleneimine/fIuorecein isothiocyanate complex (Polyplex) coated iron-oxide nanoparticles (Magnetite) were synthesized employing co-precipitation, epoxidation and EDC/NHS coupling reactions. The Polyplex coated magnetite (Nano-co-Plex) was loaded with BCNU for potential magnetically targeted delivery to the brain following intranasal administration. The Nano-co-Plex was characterized employing Thermogravimetric analysis (TGA), Superconducting Quantum Interference Device (SQUID) magnetometry, Fourier Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), X-ray Diffractometry (XRD), Transmission Electron Microscopy (TEM) and Zetasize analysis. Results revealed superparamagnetic hexagonally shaped "core-shell" nanoparticles with cell labeling attributes, of size ranging between 30-50 nm, and a zeta potential value of + 32 ± 2 mV. The Nano-co-Plex synthesized was found to possess high degree of crystallinity with 32% Polyplex coating. The loading and release studies indicated a time-dependent loading with maximum loading capacity of 176.82 μg BCNU/mg of the carrier and maximum release of 75.8% of the loaded BCNU. Cytotoxicity of the BCNU-loaded Nano-co-Plex displayed superiority over the conventional BCNU towards human glioblastoma (HG) cells. Cell studies revealed enhanced uptake and internalization of BCNU-loaded Nano-co-plex in HG cells in the presence of an external magnetic field. These Nano-co-Plexes may be ideal as an intranasal magnetic drug targeting device for BCNU delivery. PMID:26806465

  1. Effects of live music therapy sessions on quality of life indicators, medications administered and hospital length of stay for patients undergoing elective surgical procedures for brain.

    Science.gov (United States)

    Walworth, Darcy; Rumana, Christopher S; Nguyen, Judy; Jarred, Jennifer

    2008-01-01

    The physiological and psychological stress that brain tumor patients undergo during the entire surgical experience can considerably affect several aspects of their hospitalization. The purpose of this study was to examine the effects of live music therapy on quality of life indicators, amount of medications administered and length of stay for persons receiving elective surgical procedures of the brain. Subjects (N = 27) were patients admitted for some type of surgical procedure of the brain. Subjects were randomly assigned to either the control group receiving no music intervention (n = 13) or the experimental group receiving pre and postoperative live music therapy sessions (n = 14). Anxiety, mood, pain, perception of hospitalization or procedure, relaxation, and stress were measured using a self-report Visual Analog Scale (VAS) for each of the variables. The documented administration of postoperative pain medications; the frequency, dosage, type, and how it was given was also compared between groups. Experimental subjects live and interactive music therapy sessions, including a pre-operative session and continuing with daily sessions until the patient was discharged home. Control subjects received routine hospital care without any music therapy intervention. Differences in experimental pretest and posttest scores were analyzed using a Wilcoxon Matched-Pairs Signed-Rank test. Results indicated statistically significant differences for 4 of the 6 quality of life measures: anxiety (p = .03), perception of hospitalization (p = .03), relaxation (p = .001), and stress (p = .001). No statistically significant differences were found for mood (p > .05) or pain (p > .05) levels. Administration amounts of nausea and pain medications were compared with a Two-Way ANOVA with One Repeated Measure resulting in no significant differences between groups and medications, F(1, 51) = 0.03; p > .05. Results indicate no significant differences between groups for length of stay (t = .97

  2. Uptake of amino acids in brain tumours using positron emission tomography as an indicator for assessing metabolic activity and malignancy

    Energy Technology Data Exchange (ETDEWEB)

    Schober, O.; Meyer, G.J.; Duden, C.; Lauenstein, L.; Niggemann, J.; Mueller, J.A.; Hundeshagen, H.; Gaab, M.R.; Dietz, H.; Becker, H.

    1987-11-01

    Diagnosis and post-therapeutic follow-up of tumour patients necessitates morphological and particularly functional imaging methods. For the latter approach positron emission tomography has proven a valid tool for the measurement of perfusion, of energy consumption parameters such as oxygen extraction, glucose metabolism and amino acid uptake. However, neither perfusion nor energy consumption parameters have yielded unambiguous information on the clinical status of various tumours in respect of their malignancy and their growth status. It is shown in this paper that amino acid uptake seems to be a valid measure for the functional activity of tumour tissue for a broad range of neoplasms. The uptake of /sup 11/C-L-Methionine was measured in 33 patients having various brain tumours, and was compared with 6 patients who had an infarction, and with 8 patients suffering from arachnoidal cysts. The amino acid uptake correlated well with the histological grading of the tumours and the clinical status of the patient. The uptake was well differentiated against metabolically inactive lesions. Parallel investigations on the uptake mechanisms of amino acids in an animal model have shown that transport phenomena regulate the uptake rather than protein synthesis rates. However, protein synthesis may nevertheless exercise a control function on the transport process.

  3. WOOD ANATOMICAL STUDY AMONG THREE ECOTYPES OF Pinus merkusii IN SUMATRA AND THE POTENTIAL AS CLIMATE CHANGE INDICATOR

    Directory of Open Access Journals (Sweden)

    Yulia Sandri

    2016-09-01

    Full Text Available Recently, climate change is the one of most important environmental issue. Climate variability can be recorded by tree growing through the growth ring. Growth ring formed by cambial activity were examined in wood anatomy. In Sumatra, there are three ecotypes Pinus merkusii, namely ecotypes Kerinci, Tapanuli, and Aceh which can be distinguished morphologically. This study aims to knowing the wood anatomical characteristics of the three ecotypes and determine the potential as climate indicator. This study was conducted in October 2014 until June 2015. Sample of Kerinci ecotype was collected in Kerinci Seblat National Park, Tapanuli ecotype in Dolok Sibualbuali Natural Reserve and Aceh ecotype in Gunung Leuser National Park on a height of 130 cm using increment borer and cut on the main stem 5×5 cm for anatomical sample. Results from this study indicate that ecotype Kerinci and Tapanuli showed earlywood and latewood boundary exposing the clear growth ring, whereas in Aceh ecotype unclear. Tapanuli ecotype have the thickest tracheid diameter than ecotype Kerinci and Aceh. Ecotypes of Kerinci, Tapanuli, and Aceh has homoceluler and uniseriate ray where Aceh ecotype have the longest ray. Furthermore, Kerinci and Tapanuli ecotype have potential as climate indicator eventhough showed negative correlation, that Tapanuli ecotype show the best result and recommended in dendrochronology study.

  4. Brain Wave Analysis and School Achievement.

    Science.gov (United States)

    Wilson, Barry; And Others

    The Brain Wave Analyzer (BWA Ertl 02) was used to measure the brain potentials of 110 public school children. Resulting scores were correlated with concurrent measures of school achievement. Results indicate that certain brain wave scores have relatively low correlations with school achievement compared to traditional intelligence measures but may…

  5. The ethics of extracorporeal membrane oxygenation in brain-dead potential organ donors.

    Science.gov (United States)

    Dalle Ave, Anne L; Gardiner, Dale; Shaw, David M

    2016-05-01

    Organ-preserving extracorporeal membrane oxygenation (OP-ECMO) is defined as the use of extracorporeal support for the primary purpose of preserving organs for transplantation, rather than to save the patient's life. This paper discusses the ethics of using OP-ECMO in donation after brain determination of death (DBDD) to avoid the loss of organs for transplantation. We review case reports in the literature and analyze the ethical issues raised. We conclude that there is little additional ethical concern in continuing OP-ECMO in patients already on ECMO if they become brain dead. The implementation of OP-ECMO in hemodynamically unstable brain-dead patients is ethically permissible in certain clinical situations but requires specific consent from relatives if the patient's wish to donate is not clear. If no evidence of a patient's wish to donate is available, OP-ECMO is not recommended. In countries with presumed consent legislation, failure to opt out should be considered as a positive wish to donate. If a patient is not-yet brain-dead or is undergoing testing for brain death, OP-ECMO is not recommended. Further research on OP-ECMO is needed to better understand the attitudes of professionals, families, and lay people to ensure agreement on key ethical issues. PMID:26987689

  6. Who are you talking about? Tracking discourse-level referential processing with event-related brain potentials

    OpenAIRE

    Nieuwland, M.; Otten, M.; Berkum, J.

    2007-01-01

    In this event-related brain potentials (ERPs) study, we explored the possibility to selectively track referential ambiguity during spoken discourse comprehension. Earlier ERP research has shown that referentially ambiguous nouns (e.g., “the girl” in a two-girl context) elicit a frontal, sustained negative shift relative to unambiguous control words. In the current study, we examined whether this ERP effect reflects “deep” situation model ambiguity or “superficial” textbase ambiguity. We contr...

  7. Potential brain language reorganization in a boy with refractory epilepsy; an fNIRS–EEG and fMRI comparison

    OpenAIRE

    Phetsamone Vannasing; Isotta Cornaggia; Catherine Vanasse; Julie Tremblay; Paola Diadori; Sébastien Perreault; Maryse Lassonde; Anne Gallagher

    2016-01-01

    As part of a presurgical investigation for a resection of a tumor located in the left temporal brain region, we evaluated pre- and postsurgical language lateralization in a right-handed boy with refractory epilepsy. In this study, we compared functional near infrared spectroscopy (fNIRS) results obtained while the participant performed expressive and receptive language tasks with those obtained using functional magnetic resonance imaging (fMRI). This case study illustrates the potential for N...

  8. Deficits in facial emotion recognition indicate behavioral changes and impaired self-awareness after moderate to severe traumatic brain injury.

    Directory of Open Access Journals (Sweden)

    Jacoba M Spikman

    Full Text Available Traumatic brain injury (TBI is a leading cause of disability, specifically among younger adults. Behavioral changes are common after moderate to severe TBI and have adverse consequences for social and vocational functioning. It is hypothesized that deficits in social cognition, including facial affect recognition, might underlie these behavioral changes. Measurement of behavioral deficits is complicated, because the rating scales used rely on subjective judgement, often lack specificity and many patients provide unrealistically positive reports of their functioning due to impaired self-awareness. Accordingly, it is important to find performance based tests that allow objective and early identification of these problems. In the present study 51 moderate to severe TBI patients in the sub-acute and chronic stage were assessed with a test for emotion recognition (FEEST and a questionnaire for behavioral problems (DEX with a self and proxy rated version. Patients performed worse on the total score and on the negative emotion subscores of the FEEST than a matched group of 31 healthy controls. Patients also exhibited significantly more behavioral problems on both the DEX self and proxy rated version, but proxy ratings revealed more severe problems. No significant correlation was found between FEEST scores and DEX self ratings. However, impaired emotion recognition in the patients, and in particular of Sadness and Anger, was significantly correlated with behavioral problems as rated by proxies and with impaired self-awareness. This is the first study to find these associations, strengthening the proposed recognition of social signals as a condition for adequate social functioning. Hence, deficits in emotion recognition can be conceived as markers for behavioral problems and lack of insight in TBI patients. This finding is also of clinical importance since, unlike behavioral problems, emotion recognition can be objectively measured early after injury

  9. Serial and static brain radioangiogram in diagnosis of carotid disease: value, indication and limits by comparative study with EEG, Doppler study and cerebral arteriography

    International Nuclear Information System (INIS)

    Value, indication and limits of serial and static brain radioangiogram in carotid disease are studied comparatively with EEG, Doppler study and cerebral arteriograhy. The isotopic study shows the occlusion and its consequences on middle cerebral artery and cerebral hemisphere. The 'Hot-Nose' sign is rarely seen, but then with large focal abnormalities. In 20% of studied cases, isotopic study provides information about the efficiency of suppleance circulation or the existence of a blood derivation. The value of serial and static scintigraphy deserves it a better place among the non invasive diagnosis method of carotid disease

  10. Quantification of potential impurities by a stability indicating UV-HPLC method in niacinamide active pharmaceutical ingredient.

    Science.gov (United States)

    Thomas, Saji; Bharti, Amber; Tharpa, Kalsang; Agarwal, Ashutosh

    2012-02-23

    A sensitive, stability indicating reverse phase UV-HPLC method has been developed for the quantitative determination of potential impurities of niacinamide active pharmaceutical ingredient. Efficient chromatographic separation was achieved on C18 stationary phase in isocratic mode using simple mobile phase. Forced degradation study confirmed that the newly developed method was specific and selective to the degradation products. Major degradation of the drug substance was found to occur under oxidative stress conditions to form niacinamide N-oxide. The method was validated according to ICH guidelines with respect to specificity, precision, linearity and accuracy. Regression analysis showed correlation coefficient value greater than 0.999 for niacinamide and its six impurities. Detection limit of impurities was in the range of 0.003-0.005% indicating the high sensitivity of the newly developed method. Accuracy of the method was established based on the recovery obtained between 93.3% and 113.3% for all impurities.

  11. Evaluating the potential of vegetation indices for winter wheat LAI estimation under different fertilization and water conditions

    Science.gov (United States)

    Xie, Qiaoyun; Huang, Wenjiang; Dash, Jadunandan; Song, Xiaoyu; Huang, Linsheng; Zhao, Jinling; Wang, Renhong

    2015-12-01

    Leaf area index (LAI) is an important indicator for monitoring crop growth conditions and forecasting grain yield. Many algorithms have been developed for remote estimation of the leaf area index of vegetation, such as using spectral vegetation indices, inversion of radiative transfer models, and supervised learning techniques. Spectral vegetation indices, mathematical combination of reflectance bands, are widely used for LAI estimation due to their computational simplicity and their applications ranged from the leaf scale to the entire globe. However, in many cases, their applicability is limited to specific vegetation types or local conditions due to species specific nature of the relationship used to transfer the vegetation indices to LAI. The overall objective of this study is to investigate the most suitable vegetation index for estimating winter wheat LAI under eight different types of fertilizer and irrigation conditions. Regression models were used to estimate LAI using hyperspectral reflectance data from the Pushbroom Hyperspectral Imager (PHI) and in-situ measurements. Our results showed that, among six vegetation indices investigated, the modified soil-adjusted vegetation index (MSAVI) and the normalized difference vegetation index (NDVI) exhibited strong and significant relationships with LAI, and thus were sensitive across different nitrogen and water treatments. The modified triangular vegetation index (MTVI2) confirmed its potential on crop LAI estimation, although second to MSAVI and NDVI in our study. The enhanced vegetation index (EVI) showed moderate performance. However, the ratio vegetation index (RVI) and the modified simple ratio index (MSR) predicted the least accurate estimations of LAI, exposing the simple band ratio index's weakness under different treatment conditions. The results support the use of vegetation indices for a quick and effective LAI mapping procedure that is suitable for winter wheat under different management practices.

  12. The Effects of Video Games on Cognition and Brain Structure: Potential Implications for Neuropsychiatric Disorders.

    Science.gov (United States)

    Shams, Tahireh A; Foussias, George; Zawadzki, John A; Marshe, Victoria S; Siddiqui, Ishraq; Müller, Daniel J; Wong, Albert H C

    2015-09-01

    Video games are now a ubiquitous form of entertainment that has occasionally attracted negative attention. Video games have also been used to test cognitive function, as therapeutic interventions for neuropsychiatric disorders, and to explore mechanisms of experience-dependent structural brain changes. Here, we review current research on video games published from January 2011 to April 2014 with a focus on studies relating to mental health, cognition, and brain imaging. Overall, there is evidence that specific types of video games can alter brain structure or improve certain aspects of cognitive functioning. Video games can also be useful as neuropsychological assessment tools. While research in this area is still at a very early stage, there are interesting results that encourage further work in this field, and hold promise for utilizing this technology as a powerful therapeutic and experimental tool.

  13. The Effects of Video Games on Cognition and Brain Structure: Potential Implications for Neuropsychiatric Disorders.

    Science.gov (United States)

    Shams, Tahireh A; Foussias, George; Zawadzki, John A; Marshe, Victoria S; Siddiqui, Ishraq; Müller, Daniel J; Wong, Albert H C

    2015-09-01

    Video games are now a ubiquitous form of entertainment that has occasionally attracted negative attention. Video games have also been used to test cognitive function, as therapeutic interventions for neuropsychiatric disorders, and to explore mechanisms of experience-dependent structural brain changes. Here, we review current research on video games published from January 2011 to April 2014 with a focus on studies relating to mental health, cognition, and brain imaging. Overall, there is evidence that specific types of video games can alter brain structure or improve certain aspects of cognitive functioning. Video games can also be useful as neuropsychological assessment tools. While research in this area is still at a very early stage, there are interesting results that encourage further work in this field, and hold promise for utilizing this technology as a powerful therapeutic and experimental tool. PMID:26216589

  14. Association of Serum Vitamin D with the Risk of Incident Dementia and Subclinical Indices of Brain Aging: The Framingham Heart Study

    Science.gov (United States)

    Karakis, Ioannis; Pase, Matthew P.; Beiser, Alexa; Booth, Sarah L.; Jacques, Paul F.; Rogers, Gail; DeCarli, Charles; Vasan, Ramachandran S.; Wang, Thomas J.; Himali, Jayandra J.; Annweiler, Cedric; Seshadri, Sudha

    2016-01-01

    Background Identifying nutrition- and lifestyle-based risk factors for cognitive impairment and dementia may aid future primary prevention efforts. Objective We aimed to examine the association of serum vitamin D levels with incident all-cause dementia, clinically characterized Alzheimer’s disease (AD), MRI markers of brain aging, and neuropsychological function. Methods Framingham Heart Study participants had baseline serum 25-hydroxyvitamin D (25(OH)D) concentrations measured between 1986 and 2001. Vitamin D status was considered both as a continuous variable and dichotomized as deficient (<10 ng/mL), or at the cohort-specific 20th and 80th percentiles. Vitamin D was related to the 9-year risk of incident dementia (n= 1663), multiple neuropsychological tests (n= 1291) and MRI markers of brain volume, white matter hyperintensities and silent cerebral infarcts (n = 1139). Results In adjusted models, participants with vitamin D deficiency (n = 104, 8% of the cognitive sample) displayed poorer performance on Trail Making B-A (β = −0.03 to −0.05 ±0.02) and the Hooper Visual Organization Test (β = −0.09 to −0.12 ±0.05), indicating poorer executive function, processing speed, and visuo-perceptual skills. These associations remained when vitamin D was examined as a continuous variable or dichotomized at the cohort specific 20th percentile. Vitamin D deficiency was also associated with lower hippocampal volumes (β = −0.01 ±0.01) but not total brain volume, white matter hyperintensities, or silent brain infarcts. No association was found between vitamin D deficiency and incident all-cause dementia or clinically characterized AD. Conclusions In this large community-based sample, low 25(OH)D concentrations were associated with smaller hippocampal volume and poorer neuropsychological function. PMID:26890771

  15. αT-catenin in restricted brain cell types and its potential connection to autism

    OpenAIRE

    Folmsbee, Stephen Sai; Wilcox, Douglas R.; Tyberghein, Koen; De Bleser, Pieter; Tourtellotte, Warren G.; van Hengel, Jolanda; van Roy, Frans; Gottardi, Cara J.

    2016-01-01

    Background Recent genetic association studies have linked the cadherin-based adherens junction protein alpha-T-catenin (αT-cat, CTNNA3) with the development of autism. Where αT-cat is expressed in the brain, and how its loss could contribute to this disorder, are entirely unknown. Methods We used the αT-cat knockout mouse to examine the localization of αT-cat in the brain, and we used histology and immunofluorescence analysis to examine the neurobiological consequences of its loss. Results We...

  16. TVA–based assessment of attentional capacities – associations with age and indices of brain white matter microstructure

    Directory of Open Access Journals (Sweden)

    Thomas eEspeseth

    2014-10-01

    Full Text Available In this study the primary aims were to characterize the effects of age on basic components of visual attention derived from assessments based on a theory of visual attention (TVA in 325 healthy volunteers covering the adult lifespan (19-81 years. Furthermore, we aimed to investigate how age-related differences on TVA parameters are associated with white matter (WM microstructure as indexed by diffusion tensor imaging (DTI. Finally, we explored how TVA parameter estimates were associated with complex, or multicomponent indices of processing speed (Digit-symbol substitution, DSS and fluid intelligence (gF. The results indicated that the TVA parameters for visual short-term memory capacity, K, and for attentional selectivity, α, were most strongly associated with age before the age of 50. However, in this age range, it was the parameter for processing speed, C, that was most clearly associated with DTI indices, in this case fractional anisotropy (FA, particularly in the genu and body of the corpus callosum. Furthermore, differences in the C parameter partially mediated differences in DSS within this age range. After the age of 50, the TVA parameter for the perceptual threshold, t0, as well as K, were most strongly related to participant age. Both parameters, but t0 more strongly so than K, were associated WM diffusivity, particularly in projection fibers such as the internal capsule, the sagittal stratum, and the corona radiata. Within this age range, t0 partially mediated age-related differences in gF. The results are consistent with, and provide novel empirical support for the neuroanatomical localization of TVA computations as outlined in the neuronal interpretation of TVA (NTVA. Furthermore, the results indicate that to understand the biological sources of age-related changes in processing speed and fluid cognition, it may be useful to employ methods that allow for computational fractionation of these multicomponent measures.

  17. Abnormal neural connectivity in schizophrenia and fMRI-brain computer interface as a potential therapeutic approach

    Directory of Open Access Journals (Sweden)

    Sergio eRuiz

    2013-03-01

    Full Text Available Considering that single locations of structural and functional abnormalities are insufficient to explain the diverse psychopathology of schizophrenia, new models have postulated that the impairments associated with the disease arise from a failure to integrate the activity of local and distributed neural circuits: the abnormal neural connectivity hypothesis. In the last years, new evidence coming from neuroimaging have supported and expanded this theory. However, despite the increasing evidence that schizophrenia is a disorder of neural connectivity, so far there are no treatments that have shown to produce a significant change in brain connectivity, or that have been specifically designed to alleviate this problem. Brain-Computer Interfaces based on real-time functional Magnetic Resonance Imaging (fMRI-BCI are novel techniques that have allowed subjects to achieve self-regulation of circumscribed brain regions. In recent studies, experiments with this technology have resulted in new findings suggesting that this methodology could be used to train subjects to enhance brain connectivity, and therefore could potentially be used as a therapeutic tool in mental disorders including schizophrenia.The present article summarizes the findings coming from hemodynamics-based neuroimaging that support the abnormal connectivity hypothesis in schizophrenia, and discusses a new approach that could address this problem.

  18. Depression of the photic after discharge of flash evoked potentials by physostigmine, carbaryl and propoxur, and the relationship to inhibition of brain cholinesterase.

    Science.gov (United States)

    Mwanza, Jean-Claude; Finley, Dana; Spivey, Christopher L; Graff, Jaimie E; Herr, David W

    2008-01-01

    The effects of N-methyl carbamate pesticides on the photic after discharge (PhAD) of flash evoked potentials (FEPs) and the relationship between inhibition of brain cholinesterase (ChE) activity and the PhAD were evaluated. FEPs were recorded in Long Evans rats treated with physostigmine (s.c.) 0, 0.05, 0.1, 0.2 or 0.3mg/kg (free base), in an ascorbic acid/saline vehicle, carbaryl (p.o.) 0, 1, 3, 10, 30, 50 or 75 mg/kg, or propoxur (p.o.) 0, 0.3, 3, 10, 20, 30, or 40 mg/kg in a corn oil vehicle. Physostigmine served as positive control based on literature data. Early (e.g. peak N(36)) and late FEP components (peak N(166) and PhAD) are related to the initial retino-geniculate afferent volley and higher cortical processing of visual information, respectively. Compared to controls, the PhAD duration decreased following treatment with 0.1 and 0.3mg/kg physostigmine, 7 5 mg/kg carbaryl or 30 mg/kg propoxur. Lesser changes were noted in FEP amplitudes or peak latencies. Treatment with 0.2 or 0.3 mg/kg physostigmine increased peak N(36) latency. Peak N(166) latency increased only following exposure to 40 mg/kg propoxur. None of the compounds altered peak N(36) or N(166) amplitudes. Hypothermia was observed at doses greater than 0.05 mg/kg physostigmine, at 30 or 50 mg/kg carbaryl, and after treatment with 10, 20 or 40 mg/kg propoxur. Inhibition of brain ChE activity occurred at dosages greater than 0.05 mg/kg physostigmine, 1mg/kg carbaryl, and 0.3 mg/kg propoxur. Linear regression analysis indicated that the decrease in PhAD duration correlated with decrease in brain ChE activity. The results indicate that at 30 min after treatment, inhibition of brain ChE activity did not affect cortical processing of the input from the retino-geniculate volley (evidenced by unaltered peak N(36) amplitude). However, the data suggest that disruption of cortical processing of visual signals related to FEP late components, as indicated by depression of the PhAD, was related to inhibition

  19. Design requirements and potential target users for brain-computer interfaces – recommendations from rehabilitation professionals

    NARCIS (Netherlands)

    Nijboer, F.; Plass-Oude Bos, D.; Blokland, Y.M.; Wijk, R. van; Farquhar, J.D.R.

    2014-01-01

    It is an implicit assumption in the field of brain-computer interfacing (BCI) that BCIs can be satisfactorily used to access augmentative and alternative communication (AAC) methods by people with severe physical disabilities. A one-day workshop and focus group interview was held to investigate this

  20. ROS and Brain Gliomas: An Overview of Potential and Innovative Therapeutic Strategies

    Directory of Open Access Journals (Sweden)

    Mariagrazia Rinaldi

    2016-06-01

    Full Text Available Reactive oxygen species (ROS represent reactive products belonging to the partial reduction of oxygen. It has been reported that ROS are involved in different signaling pathways to control cellular stability. Under normal conditions, the correct function of redox systems leads to the prevention of cell oxidative damage. When ROS exceed the antioxidant defense system, cellular stress occurs. The cellular redox impairment is strictly related to tumorigenesis. Tumor cells, through the generation of hydrogen peroxide, tend to the alteration of cell cycle phases and, finally to cancer progression. In adults, the most common form of primary malignant brain tumors is represented by gliomas. The gliomagenesis is characterized by numerous molecular processes all characterized by an altered production of growth factor receptors. The difficulty to treat brain cancer depends on several biological mechanisms such as failure of drug delivery through the blood-brain barrier, tumor response to chemotherapy, and intrinsic resistance of tumor cells. Understanding the mechanisms of ROS action could allow the formulation of new therapeutic protocols to treat brain gliomas.

  1. Blood-brain barrier leakage after status epilepticus in rapamycin-treated rats II: Potential mechanisms

    NARCIS (Netherlands)

    E.A. van Vliet; W.M. Otte; W.J. Wadman; E. Aronica; G. Kooij; H.E. de Vries; R.M. Dijkhuizen; J.A. Gorter

    2016-01-01

    OBJECTIVE: Blood-brain barrier (BBB) leakage may play a pro-epileptogenic role after status epilepticus. In the accompanying contrast-enhanced magnetic resonance imaging (CE-MRI) study we showed that the mammalian target of rapamycin (mTOR) inhibitor rapamycin reduced BBB leakage and seizure activit

  2. Blood-brain barrier leakage after status epilepticus in rapamycin-treated rats II : Potential mechanisms

    NARCIS (Netherlands)

    van Vliet, Erwin A; Otte, Wim M; Wadman, Wytse J; Aronica, Eleonora; Kooij, Gijs; de Vries, Helga E; Dijkhuizen, Rick M; Gorter, Jan A

    2016-01-01

    OBJECTIVE: Blood-brain barrier (BBB) leakage may play a pro-epileptogenic role after status epilepticus. In the accompanying contrast-enhanced magnetic resonance imaging (CE-MRI) study we showed that the mammalian target of rapamycin (mTOR) inhibitor rapamycin reduced BBB leakage and seizure activit

  3. Brain-potential analysis of visual word recognition in dyslexics and typically reading children

    NARCIS (Netherlands)

    G. Fraga González; G. Žarić; J. Tijms; M. Bonte; L. Blomert; M.W. van der Molen

    2014-01-01

    The specialization of visual brain areas for fast processing of printed words plays an important role in the acquisition of reading skills. Dysregulation of these areas may be among the deficits underlying developmental dyslexia. The present study examines the specificity of word activation in dysle

  4. No impact of deep brain stimulation on fear–potentiated startle in obsessive-compulsive disorder

    NARCIS (Netherlands)

    Baas, Johanna M P; Klumpers, Floris; Mantione, Mariska H.; Figee, Martijn; Vulink, Nienke C.; Richard Schuurman, P.; Mazaheri, Ali; Denys, Damiaan

    2014-01-01

    Deep brain stimulation (DBS) of the ventral internal capsule is effective in treating therapy refractory obsessive-compulsive disorder (OCD). Given the close proximity of the stimulation site to the stria terminalis (BNST), we hypothesized that the striking decrease in anxiety symptoms following DBS

  5. No impact of deep brain stimulation on fear-potentiated startle in obsessive-compulsive disorder

    NARCIS (Netherlands)

    Baas, Johanna M P; Klumpers, Floris; Mantione, Mariska H; Figee, Martijn; Vulink, Nienke C; Schuurman, P Richard; Mazaheri, Ali; Denys, D.

    2014-01-01

    Deep brain stimulation (DBS) of the ventral internal capsule is effective in treating therapy refractory obsessive-compulsive disorder (OCD). Given the close proximity of the stimulation site to the stria terminalis (BNST), we hypothesized that the striking decrease in anxiety symptoms following DBS

  6. Event-Related Brain Potentials Reveal Anomalies in Temporal Processing of Faces in Autism Spectrum Disorder

    Science.gov (United States)

    McPartland, James; Dawson, Geraldine; Webb, Sara J.; Panagiotides, Heracles; Carver, Leslie J.

    2004-01-01

    Background: Individuals with autism exhibit impairments in face recognition, and neuroimaging studies have shown that individuals with autism exhibit abnormal patterns of brain activity during face processing. The current study examined the temporal characteristics of face processing in autism and their relation to behavior. Method: High-density…

  7. Intranasal delivery of nanoparticle encapsulated tarenflurbil: A potential brain targeting strategy for Alzheimer's disease.

    Science.gov (United States)

    Muntimadugu, Eameema; Dhommati, Raju; Jain, Anjali; Challa, Venu Gopala Swami; Shaheen, M; Khan, Wahid

    2016-09-20

    Poor brain penetration of tarenflurbil (TFB) was one of the major reasons for its failure in phase III clinical trials conducted on Alzheimer's patients. Thus there is a tremendous need of developing efficient delivery systems for TFB. This study was designed with the aim of improving drug delivery to brain through intranasally delivered nanocarriers. TFB was loaded into two different nanocarriers i.e., poly (lactide-co-glycolide) nanoparticles (TFB-NPs) and solid lipid nanoparticles (TFB-SLNs). Particle size of both the nanocarriers (TFB-SLNs (i.n.)>TFB solution (i.n.)>TFB suspension (oral). Brain targeting efficiency was determined in terms of %drug targeting efficiency (%DTE) and drug transport percentage (DTP). The higher %DTE (287.24) and DTP (65.18) were observed for TFB-NPs followed by TFB-SLNs (%DTE: 183.15 and DTP: 45.41) among all other tested groups. These encouraging results proved that therapeutic concentrations of TFB could be transported directly to brain via olfactory pathway after intranasal administration of polymeric and lipidic nanoparticles. PMID:27185298

  8. Indication of lower neck irradiation in nasopharyngeal carcinoma without nodal metastasis: the potential impact of tumor volume

    Institute of Scientific and Technical Information of China (English)

    FU Jie; ZHOU Jia-yin; Vincent FH CHONG; James BK Khoo

    2013-01-01

    Background Elective radiation of lower neck is controversial for nasopharyngeal carcinoma (NPC) without lymph node metastasis (N0 disease).Tumor volume is an important prognostic indicator.The objective of this study is to explore the potential impact of tumor volume on the indication of the lower neck irradiation for N0-NPC,by a qualitative evaluation of the relationship between tumor volume and nodal metastasis.Methods Magnetic resonance (MR) images of 99 consecutive patients with NPC who underwent treatment were retrospectively reviewed.Primary tumor volumes of NPC were semi-automatically measured,nodal metastases were N-classified and neck level involvements were examined.Distributions of tumor volumes among N-category-based groups and distributions of N-categories among tumor volume-based groups were analyzed,respectively.Results The numbers of patients with N0 to N3 disease were 12,39,32,and 16,respectively.The volumes of primary tumor were from 3.3 to 89.6 ml,with a median of 17.1 ml.For patients with nodal metastasis,tumor volume did not increase significantly with the advancing of N-category (P >0.05).No significant difference was found for the distribution of N1,N2,and N3 categories among tumor volume-based groups (P >0.05).Nevertheless patients with nodal metastasis had significantly larger tumor volumes than those without metastasis (P <0.05).Patients with larger tumor volumes were associated with an increased incidence of nodal metastasis.Conclusions Certain positive correlations existed between tumor volume and the presence of nodal metastasis.The tumor volume (>10 ml) is a potential indicator for the lower neck irradiation for N0-NPC.

  9. Indicators of hydrological, biogeochemical and ecological integrity for estimating potential loss of ecosystem services from wetlands on domesticated landscapes

    Science.gov (United States)

    Creed, I. F.; Aldred, D.; Spargo, A.; Bayley, S.

    2012-12-01

    these indicators over the past years. For a time series of wetlands loss we derive these indicators of functions and benefits to estimate changes in the provision of specific aquatic ecosystem services on the landscape. Last, we develop formulae for integrating these indicators to determine whether a specific wetland or wetland complex should be prioritized for conservation, exemplifying potential trade-offs among ecosystem services in setting conservation targets on this wetland dominated landscapes. The proposed theoretical framework evolved from close collaboration between scientists and resource managers, and will inform those engaged in developing wetland policies for a broad range of jurisdictions.

  10. Naphthenic acids in coastal sediments after the Hebei Spirit oil spill: a potential indicator for oil contamination.

    Science.gov (United States)

    Wan, Yi; Wang, Beili; Khim, Jong Seong; Hong, Seongjin; Shim, Won Joon; Hu, Jianying

    2014-04-01

    Naphthenic acids (NAs) as toxic components in most petroleum sources are suspected to be one of the major pollutants in the aquatic environment following oil spills, and the polarity and persistence of NAs make it a potential indicator for oil contamination. However, the contamination and potential effects of pollutants in oil spill affected areas remain unknown. To investigate NAs in oil spill affected areas, a sensitive method was first established for analysis of NAs, together with oxy-NAs in sediment samples by UPLC-QTOF-MS. Then the method was applied to determine the NA mixtures in crude oil, weathered oil, and sediments from the spilled sites after the Hebei Spirit oil spill, Taean, South Korea (Dec. 2007). Concentrations of NAs, O3-NAs, and O4-NAs were found to be 7.8-130, 3.6-44, and 0.8-20 mg kg(-1) dw in sediments from the Taean area, respectively, which were much greater than those measured in the reference sites of Manlipo and Anmyundo beaches. Concentrations of NAs were 50-100 times greater than those (0.077-2.5 mg kg(-1) dw) of PAHs in the same sediment samples, thus the ecological risk of NAs in oil spill affected areas deserves more attention. The sedimentary profiles of oil-derived NAs and background NAs centered around compounds with 21-35 and 12-21 carbons, respectively, indicating that the crude-derived NA mixtures originating from the 2007 oil spill were persistent. Acyclic NAsn=5-20 were easily degraded compared to cyclic NAsn=21-41 during the oil weathering processes, and the ratio of oxy-NAsn=21-41 relative to NAsn=21-41 could be a novel index to estimate the degree of oil weathering in sediments. Altogether, the persistent oil-derived NAsn=21-41 could be used as a potential indicator for oil-specific contamination, as such compounds would not be much affected by the properties of coastal sediments possibly due to the high sorption of the negatively charged compounds (NAs) in sediment.

  11. Auditory brain-stem evoked potentials in cat after kainic acid induced neuronal loss. II. Cochlear nucleus.

    Science.gov (United States)

    Zaaroor, M; Starr, A

    1991-01-01

    Auditory brain-stem potentials (ABRs) were studied in cats for up to 6 weeks after kainic acid had been injected unilaterally into the cochlear nucleus (CN) producing extensive neuronal destruction. The ABR components were labeled by the polarity at the vertex (P, for positive) and their order of appearance (the arabic numerals 1, 2, etc.). Component P1 can be further subdivided into 2 subcomponents, P1a and P1b. The assumed correspondence between the ABR components in cat and man is indicated by providing human Roman numeral designations in parentheses following the feline notation, e.g., P2 (III). To stimulation of the ear ipsilateral to the injection, the ABR changes consisted of a loss of components P2 (III) and P3 (IV), and an attenuation and prolongation of latency of components P4 (V) and P5 (VI). The sustained potential shift from which the components arose was not affected. Wave P1a (I) was also slightly but significantly attenuated compatible with changes of excitability of nerve VIII in the cochlea secondary to cochlear nucleus destruction. Unexpectedly, to stimulation of the ear contralateral to the injection side, waves P2 (III), P3 (IV), and P4 (V) were also attenuated and delayed in latency but to a lesser degree than to stimulation of the ear ipsilateral to the injection. Changes in binaural interaction of the ABR following cochlear nucleus lesions were similar to those produced in normal animals by introducing a temporal delay of the input to one ear. The results of the present set of studies using kainic acid to induce neuronal loss in auditory pathway when combined with prior lesion and recording experiments suggest that each of the components of the ABR requires the integrity of an anatomically diffuse system comprising a set of neurons, their axons, and the neurons on which they terminate. Disruption of any portion of the system will alter the amplitude and/or the latency of that component. PMID:1716569

  12. Asparagine Depletion Potentiates the Cytotoxic Effect of Chemotherapy Against Brain Tumors

    OpenAIRE

    Panosyan, Eduard H.; Wang, Yuntao; Xia, Peng; Lee, Wai-Nang Paul; Pak, Youngju; Laks, Dan R.; Lin, Henry J.; Moore, Theodore B.; Cloughesy, Timothy F.; Kornblum, Harley I.; Lasky, Joseph L.

    2014-01-01

    Targeting amino acid metabolism has therapeutic implications for aggressive brain tumors. Asparagine is an amino acid that is synthesized by normal cells. However, some cancer cells lack asparagine synthetase (ASNS), the key enzyme for asparagine synthesis. Asparaginase (ASNase) contributes to eradication of acute leukemia by decreasing asparagine levels in serum and cerebrospinal fluid. However, leukemic cells may become ASNase-resistant by up-regulating ASNS. High expression of ASNS has als...

  13. Subject Combination and Electrode Selection in Cooperative Brain-Computer Interface Based on Event Related Potentials

    OpenAIRE

    Hubert Cecotti; Bertrand Rivet

    2014-01-01

    New paradigms are required in Brain-Computer Interface (BCI) systems for the needs and expectations of healthy people. To solve this issue, we explore the emerging field of cooperative BCIs, which involves several users in a single BCI system. Contrary to classical BCIs that are dependent on the unique subject’s will, cooperative BCIs are used for problem solving tasks where several people shall be engaged by sharing a common goal. Similarly as combining trials over time improves performance,...

  14. Toward brain-computer interface based wheelchair control utilizing tactually-evoked event-related potentials

    OpenAIRE

    Kaufmann, Tobias; Herweg, Andreas; Kübler, Andrea

    2014-01-01

    Background People with severe disabilities, e.g. due to neurodegenerative disease, depend on technology that allows for accurate wheelchair control. For those who cannot operate a wheelchair with a joystick, brain-computer interfaces (BCI) may offer a valuable option. Technology depending on visual or auditory input may not be feasible as these modalities are dedicated to processing of environmental stimuli (e.g. recognition of obstacles, ambient noise). Herein we thus validated the feasi...

  15. Task-Induced Brain Activity Patterns in Type 2 Diabetes: A Potential Biomarker for Cognitive Decline

    OpenAIRE

    Marder, Thomas J.; Flores, Veronica L.; Bolo, Nicolas R.; Hoogenboom, Wouter S.; Simonson, Donald C.; Jacobson, Alan M.; Foote, Sarah E.; Martha E. Shenton; Sperling, Reisa A.; Musen, Gail

    2014-01-01

    Patients with type 2 diabetes demonstrate reduced functional connectivity within the resting state default mode network (DMN), which may signal heightened risk for cognitive decline. In other populations at risk for cognitive decline, additional magnetic resonance imaging abnormalities are evident during task performance, including impaired deactivation of the DMN and reduced activation of task-relevant regions. We investigated whether middle-aged type 2 diabetic patients show these brain act...

  16. Electrical stimulation alleviates depressive-like behaviors of rats: investigation of brain targets and potential mechanisms.

    Science.gov (United States)

    Lim, L W; Prickaerts, J; Huguet, G; Kadar, E; Hartung, H; Sharp, T; Temel, Y

    2015-01-01

    Deep brain stimulation (DBS) is a promising therapy for patients with refractory depression. However, key questions remain with regard to which brain target(s) should be used for stimulation, and which mechanisms underlie the therapeutic effects. Here, we investigated the effect of DBS, with low- and high-frequency stimulation (LFS, HFS), in different brain regions (ventromedial prefrontal cortex, vmPFC; cingulate cortex, Cg; nucleus accumbens (NAc) core or shell; lateral habenula, LHb; and ventral tegmental area) on a variety of depressive-like behaviors using rat models. In the naive animal study, we found that HFS of the Cg, vmPFC, NAc core and LHb reduced anxiety levels and increased motivation for food. In the chronic unpredictable stress model, there was a robust depressive-like behavioral phenotype. Moreover, vmPFC HFS, in a comparison of all stimulated targets, produced the most profound antidepressant effects with enhanced hedonia, reduced anxiety and decreased forced-swim immobility. In the following set of electrophysiological and histochemical experiments designed to unravel some of the underlying mechanisms, we found that vmPFC HFS evoked a specific modulation of the serotonergic neurons in the dorsal raphe nucleus (DRN), which have long been linked to mood. Finally, using a neuronal mapping approach by means of c-Fos expression, we found that vmPFC HFS modulated a brain circuit linked to the DRN and known to be involved in affect. In conclusion, HFS of the vmPFC produced the most potent antidepressant effects in naive rats and rats subjected to stress by mechanisms also including the DRN. PMID:25826110

  17. Voxel-based analysis of diffusion tensor indices in the brain in patients with Parkinson's disease

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Kaiyuan, E-mail: kaiyuanzhang@yahoo.cn [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Key Laboratory of Neurodegenerative Diseases, Capital Medical University, Ministry of Education (China); Yu Chunshui, E-mail: chunshuiyu826@yahoo.com.cn [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Key Laboratory of Neurodegenerative Diseases, Capital Medical University, Ministry of Education (China); Zhang Yujin, E-mail: zyjinjin@gmail.com [State Key Laboratory of Cognitive Neurosciences and Learning, Beijing Normal University, Beijing 100875 (China); Wu Xiaoli, E-mail: wendy2006315@126.com [Key Laboratory of Neurodegenerative Diseases, Capital Medical University, Ministry of Education (China) and Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Zhu Chaozhe, E-mail: czzhu@bnu.edu.cn [State Key Laboratory of Cognitive Neurosciences and Learning, Beijing Normal University, Beijing 100875 (China); Chan Piu, E-mail: pbchan@bjsap.org [Key Laboratory of Neurodegenerative Diseases, Capital Medical University, Ministry of Education (China); Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Li Kuncheng, E-mail: likuncheng1955@yahoo.com.cn [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Key Laboratory of Neurodegenerative Diseases, Capital Medical University, Ministry of Education (China)

    2011-02-15

    Purpose: To investigate the abnormal diffusion in cerebral white matter and its relationship with the olfactory dysfunction in patients with Parkinson's disease (PD) through diffusion tensor imaging (DTI). Materials and methods: Diffusion tensor imaging of the cerebrum was performed in 25 patients with Parkinson's disease and 25 control subjects matched for age and sex. Differences in fractional anisotropy (FA) and mean diffusivity (MD) between these two groups were studied by voxel-based analysis of the DTI data. Correlations between diffusion indices and the olfactory function in PD patients were evaluated using the multiple regression model after controlling for the duration of the disease, Unified Parkinson's Disease Rating Sale (UPDRS), and age. Results: The damaged white and gray matter showed decreased FA or increased MD, localized bilaterally in the cerebellar and orbitofrontal cortex. In addition, in PD patients there was a positive correlation between FA values in the white matter of the left cerebellum and the thresholds of olfactory identification (TOI) and a negative correlation between MD values in the white matter of right cerebellum and the TOI. Conclusion: In patients with PD, there was disruption in the cerebellar white matter which may play an important role in the olfactory dysfunction in patients with Parkinson's disease.

  18. Depth and activity of carious lesions as indicators for the regenerative potential of dental pulp after intervention

    DEFF Research Database (Denmark)

    Bjørndal, Lars; Pedersen, Sune Demant Nørgaard; Dabelsteen, Sally

    2014-01-01

    Studies on dental regeneration involving interventions for pulp therapy such as regeneration and revascularization procedures are promising for the injured tooth; however, a complete replication of the original pulp tissue does not seem to take place. In cases in which we wish to preserve...... that the typical reason for performing endodontic treatment is deep caries. The biological concept of vital pulp therapy associated with deep caries takes the treatment and evaluation of the unexposed as well as the exposed pulp into account. Interestingly, the clinical diagnosis is typically the same. Deep caries....... Which treatment should be selected? High-quality trials are needed, and it is important to obtain information on the actual lesion depth and an estimate of the lesion activity before treatment. These may be basic indicators for the regenerative potential of dental pulp. Recent clinical trials dealing...

  19. Analyzing indicator microorganisms, antibiotic resistant Escherichia coli, and regrowth potential of foodborne pathogens in various organic fertilizers.

    Science.gov (United States)

    Miller, Cortney; Heringa, Spencer; Kim, Jinkyung; Jiang, Xiuping

    2013-06-01

    This study analyzed various organic fertilizers for indicator microorganisms, pathogens, and antibiotic-resistant Escherichia coli, and evaluated the growth potential of E. coli O157:H7 and Salmonella in fertilizers. A microbiological survey was conducted on 103 organic fertilizers from across the United States. Moisture content ranged from approximately 1% to 86.4%, and the average pH was 7.77. The total aerobic mesophiles ranged from approximately 3 to 9 log colony-forming units (CFU)/g. Enterobacteriaceae populations were in the range of fertilizer, respectively, whereas E. coli O157:H7 grew approximately 4.6, 4.0, 4.0, and 4.8 log CFU/g, respectively. Our results revealed that the microbiological quality of organic fertilizers varies greatly, with some fertilizers containing antibiotic resistant E. coli and a few supporting the growth of foodborne pathogens after reintroduction into the fertilizer.

  20. Fluorescence excitation and propagation through brain phantom gelatins: measurements and potential applications

    Science.gov (United States)

    Allison, S. W.; Gillies, G. T.

    2010-08-01

    We have investigated the utility of 0.6% agarose gels as surrogate materials for brain tissues in optical propagation studies for possible diagnostic and therapeutic applications. Centimeter-scale layers of the gel exhibited a Beer's law attenuation factor, δ, of ≈0.2 mm-1 for incident illumination via a pulsed LED (100 Hz) at 405 nm. This result was different by only about a factor of 3 from the effective penetration depth at similar wavelengths through in vitro samples of the gray (cortical) matter of human brain, as measured by others. Then, films of the thermographic phosphors La2O2S:Eu, Mg4FGeO6:Mn, YAG:Cr and variants of the latter were formed on aluminum substrates and the fluorescence of these samples was stimulated and observed through layers of the gel up to 4 cm thick. In all cases, the fluorescence was easily excited and distinguishable above the background. The results demonstrate that this gel might serve as an inexpensive and robust test bed for exploratory studies of neurological modalities involving propagation of optical signals within brain tissues.

  1. Statistical language learning in neonates revealed by event-related brain potentials

    Directory of Open Access Journals (Sweden)

    Näätänen Risto

    2009-03-01

    Full Text Available Abstract Background Statistical learning is a candidate for one of the basic prerequisites underlying the expeditious acquisition of spoken language. Infants from 8 months of age exhibit this form of learning to segment fluent speech into distinct words. To test the statistical learning skills at birth, we recorded event-related brain responses of sleeping neonates while they were listening to a stream of syllables containing statistical cues to word boundaries. Results We found evidence that sleeping neonates are able to automatically extract statistical properties of the speech input and thus detect the word boundaries in a continuous stream of syllables containing no morphological cues. Syllable-specific event-related brain responses found in two separate studies demonstrated that the neonatal brain treated the syllables differently according to their position within pseudowords. Conclusion These results demonstrate that neonates can efficiently learn transitional probabilities or frequencies of co-occurrence between different syllables, enabling them to detect word boundaries and in this way isolate single words out of fluent natural speech. The ability to adopt statistical structures from speech may play a fundamental role as one of the earliest prerequisites of language acquisition.

  2. Overall multi-media persistence as an indicator of potential for population-level intake of environmental contaminants

    Energy Technology Data Exchange (ETDEWEB)

    MacLeod, Matthew; McKone, Thomas E.

    2003-06-01

    Although it is intuitively apparent that population-level exposure to contaminants dispersed in the environment must related to the persistence of the contaminant, there has been little effort to formally quantify this link. In this paper we investigate the relationship between overall persistence in a multimedia environment and the population-level exposure as expressed by intake fraction (iF), which is the cumulative fraction of chemical emitted to the environment that is taken up by members of the population. We first confirm that for any given chemical contaminant and emission scenario the definition of iF implies that it is directly proportional to the overall multi-media persistence, P{sub OV}. We show that the proportionality constant has dimensions of time and represents the characteristic time for population intake (CTI) of the chemical from the environment. We then apply the CalTOX fate and exposure model to explore how P{sub OV} and CTI combine to determine the magnitude of iF. We find that CTI has a narrow range of possible values relative to P{sub OV} across multiple chemicals and emissions scenarios. We use data from the Canadian Environmental Protection Act Priority Substance List (PSL1) Assessments to show that exposure assessments based on empirical observation are consistent with interpretations from the model. The characteristic time for intake along different dominant exposure pathways is discussed. Results indicate that P{sub OV} derived from screening-level assessments of persistence, bioaccumulation potential, and toxicity (PBT) is a useful indicator of the potential for population-level exposure.

  3. NOGO-A induction and localization during chick brain development indicate a role disparate from neurite outgrowth inhibition

    Directory of Open Access Journals (Sweden)

    Liwnicz Boleslaw H

    2007-04-01

    Full Text Available Abstract Background Nogo-A, a myelin-associated protein, inhibits neurite outgrowth and abates regeneration in the adult vertebrate central nervous system (CNS and may play a role in maintaining neural pathways once established. However, the presence of Nogo-A during early CNS development is counterintuitive and hints at an additional role for Nogo-A beyond neurite inhibition. Results We isolated chicken NOGO-A and determined its sequence. A multiple alignment of the amino acid sequence across divergent species, identified five previously undescribed, Nogo-A specific conserved regions that may be relevant for development. NOGO gene transcripts (NOGO-A, NOGO-B and NOGO-C were differentially expressed in the CNS during development and a second NOGO-A splice variant was identified. We further localized NOGO-A expression during key phases of CNS development by in situ hybridization. CNS-associated NOGO-A was induced coincident with neural plate formation and up-regulated by FGF in the transformation of non-neural ectoderm into neural precursors. NOGO-A expression was diffuse in the neuroectoderm during the early proliferative phase of development, and migration, but localized to large projection neurons of the optic tectum and tectal-associated nuclei during architectural differentiation, lamination and network establishment. Conclusion These data suggest Nogo-A plays a functional role in the determination of neural identity and/or differentiation and also appears to play a later role in the networking of large projection neurons during neurite formation and synaptogenesis. These data indicate that Nogo-A is a multifunctional protein with additional roles during CNS development that are disparate from its later role of neurite outgrowth inhibition in the adult CNS.

  4. Evaluation of the Potential of using Solar Energy to Pasteurise Drinking Water: Using Escherichia coli (E. coli as an Indicator

    Directory of Open Access Journals (Sweden)

    Norman Mhazo

    2010-07-01

    Full Text Available Potential application of a simple panel solar cooker design (Cookit to inactivate bacteria in drinking water was investigated. Escherichia coli (E. coli was used as an indicator species in this study. Bacterial contaminated water was collected from Mzimnene R iver in Manzini region of Sw aziland. Water samples were put in Cookits and exposed to solar radiation for different time intervals (0, 30, 60, 90, 120, 150 and 180 min. Changes in water temperature were monitored and E. coli counts (cfu/ml were enumerated for each sample. The standard solid plating procedure for enumerating bacteria was used. The results showed rapid decline in E. coli count when water temperature reached about 55ºC and this was attained within 2 h of exposure to solar radiation. The findings suggest that there is potential in using the Cookit to inactivate bacteria in drinking water. It is recommended that further investigations be conducted at a larger scale, over longer periods and under different weather and climatic conditions. The effectiveness of the Cookit should also be further evaluated with more resistant waterborne bacteria, bacterial spores, protozoan cysts, and viruses.

  5. Circulating brain-derived neurotrophic factor and indices of metabolic and cardiovascular health: data from the Baltimore Longitudinal Study of Aging.

    Directory of Open Access Journals (Sweden)

    Erin Golden

    Full Text Available BACKGROUND: Besides its well-established role in nerve cell survival and adaptive plasticity, brain-derived neurotrophic factor (BDNF is also involved in energy homeostasis and cardiovascular regulation. Although BDNF is present in the systemic circulation, it is unknown whether plasma BDNF correlates with circulating markers of dysregulated metabolism and an adverse cardiovascular profile. METHODOLOGY/PRINCIPAL FINDINGS: To determine whether circulating BDNF correlates with indices of metabolic and cardiovascular health, we measured plasma BDNF levels in 496 middle-age and elderly subjects (mean age approximately 70, in the Baltimore Longitudinal Study of Aging. Linear regression analysis revealed that plasma BDNF is associated with risk factors for cardiovascular disease and metabolic syndrome, regardless of age. In females, BDNF was positively correlated with BMI, fat mass, diastolic blood pressure, total cholesterol, and LDL-cholesterol, and inversely correlated with folate. In males, BDNF was positively correlated with diastolic blood pressure, triglycerides, free thiiodo-thyronine (FT3, and bioavailable testosterone, and inversely correlated with sex-hormone binding globulin, and adiponectin. CONCLUSION/SIGNIFICANCE: Plasma BDNF significantly correlates with multiple risk factors for metabolic syndrome and cardiovascular dysfunction. Whether BDNF contributes to the pathogenesis of these disorders or functions in adaptive responses to cellular stress (as occurs in the brain remains to be determined.

  6. Brain and personality bases of insensitivity to infant cues in neglectful mothers: an event-related potential study.

    Science.gov (United States)

    Rodrigo, María José; León, Inmaculada; Quiñones, Ileana; Lage, Agustín; Byrne, Sonia; Bobes, María Antonieta

    2011-02-01

    This investigation examined the neural and personality correlates of processing infant facial expressions in mothers with substantiated neglect of a child under 5 years old. Event-related potentials (ERPs) were recorded from 14 neglectful and 14 control mothers as they viewed and categorized pictures of infant cries, laughs, and neutral faces. Maternal self-reports of anhedonia and empathy were also completed. Early (negative occipitotemporal component peaking at around 170 ms on the scalp [N170] and positive electrical potential peaking at about 200 ms [P200]) and late positive potential (LPP) components were selected. Both groups of mothers showed behavioral discrimination between the different facial expressions via reaction time and accuracy measures. Neglectful mothers did not exhibit increased N170 amplitude at temporal leads in response to viewing crying versus laughing and neutral expressions compared to control mothers. Both groups had greater P200 and LPP amplitudes at centroparietal leads in response to viewing crying versus neutral facial expressions. However, neglectful mothers displayed an overall attenuated brain response in LPP that was related to their higher scores in social anhedonia but not to their empathy scores. The ERP data suggest that the brain's failures in the early differentiation of cry stimuli and in the sustained processing of infant expressions related to social anhedonia may underlie the insensitive responding in neglectful mothers. The implications of these results for the design and evaluation of preventive interventions are discussed.

  7. Visual encoding and fixation target selection in free viewing: presaccadic brain potentials

    Science.gov (United States)

    Nikolaev, Andrey R.; Jurica, Peter; Nakatani, Chie; Plomp, Gijs; van Leeuwen, Cees

    2013-01-01

    In scrutinizing a scene, the eyes alternate between fixations and saccades. During a fixation, two component processes can be distinguished: visual encoding and selection of the next fixation target. We aimed to distinguish the neural correlates of these processes in the electrical brain activity prior to a saccade onset. Participants viewed color photographs of natural scenes, in preparation for a change detection task. Then, for each participant and each scene we computed an image heat map, with temperature representing the duration and density of fixations. The temperature difference between the start and end points of saccades was taken as a measure of the expected task-relevance of the information concentrated in specific regions of a scene. Visual encoding was evaluated according to whether subsequent change was correctly detected. Saccades with larger temperature difference were more likely to be followed by correct detection than ones with smaller temperature differences. The amplitude of presaccadic activity over anterior brain areas was larger for correct detection than for detection failure. This difference was observed for short “scrutinizing” but not for long “explorative” saccades, suggesting that presaccadic activity reflects top-down saccade guidance. Thus, successful encoding requires local scanning of scene regions which are expected to be task-relevant. Next, we evaluated fixation target selection. Saccades “moving up” in temperature were preceded by presaccadic activity of higher amplitude than those “moving down”. This finding suggests that presaccadic activity reflects attention deployed to the following fixation location. Our findings illustrate how presaccadic activity can elucidate concurrent brain processes related to the immediate goal of planning the next saccade and the larger-scale goal of constructing a robust representation of the visual scene. PMID:23818877

  8. Visual encoding and fixation target selection in free viewing: presaccadic brain potentials

    Directory of Open Access Journals (Sweden)

    Andrey R Nikolaev

    2013-06-01

    Full Text Available In scrutinizing a scene, the eyes alternate between fixations and saccades. During a fixation, two component processes can be distinguished: visual encoding and selection of the next fixation target. We aimed to distinguish the neural correlates of these processes in the electrical brain activity prior to a saccade onset. Participants viewed color photographs of natural scenes, in preparation for a change detection task. Then, for each participant and each scene we computed an image heat map, with temperature representing the duration and density of fixations. The temperature difference between the start and end points of saccades was taken as a measure of the expected task-relevance of the information concentrated in specific regions of a scene. Visual encoding was evaluated according to whether subsequent change was correctly detected. Saccades with larger temperature difference were more likely to be followed by correct detection than ones with smaller temperature differences. The amplitude of presaccadic activity over anterior brain areas was larger for correct detection than for detection failure. This difference was observed for short scrutinizing but not for long explorative saccades, suggesting that presaccadic activity reflects top-down saccade guidance. Thus, successful encoding requires local scanning of scene regions which are expected to be task-relevant. Next, we evaluated fixation target selection. Saccades moving up in temperature were preceded by presaccadic activity of higher amplitude than those moving down. This finding suggests that presaccadic activity reflects attention deployed to the following fixation location. Our findings illustrate how presaccadic activity can elucidate concurrent brain processes related to the immediate goal of planning the next saccade and the larger-scale goal of constructing a robust representation of the visual scene.

  9. Lexical processing of vocabulary class in patients with Broca's aphasia: An event-related brain potential study on agrammatic comprehension

    OpenAIRE

    Ter Keurs, M.; Brown, C.; Hagoort, P.

    2002-01-01

    This paper presents electrophysiological evidence of an impairment in the on-line processing of word class information in patients with Broca’s aphasia with agrammatic comprehension. Event-related brain potentials (ERPs) were recorded from the scalp while Broca patients and non-aphasic control subjects read open- and closed-class words that appeared one at a time on a PC screen. Separate waveforms were computed for open- and closed-class words. The non-aphasic control subjects showed a modula...

  10. The Potential of a (nearly) Complete Structural Neuroanatomical Model of the Human Brain

    OpenAIRE

    Fernández Pujals, Ana Maria

    2011-01-01

    Generally, the main skeptical opposition that projects like the Connectome face are statements like: It is all very well to explain the machinery and mechanisms of the brain, but what will that really teach us about our selves, our minds, what makes us really tick, our mental life? People want to know, “well, what is this really going to teach us?” !is kind of skepticism is grounded in a basic preference for the familiarity of the theories of folk psychology. !ere is nothing entirely wr...

  11. Epigenetics, stress and their potential impact on brain network function: A focus on the schizophrenia diatheses

    Directory of Open Access Journals (Sweden)

    Vaibhav A. Diwadkar

    2014-06-01

    Full Text Available The recent sociodevelopmental cognitive model of schizophrenia/psychosis is a highly influential and compelling compendium of research findings. Here we present logical extensions to this model incorporating ideas drawn from epigenetic mediation of psychiatric disease, and the plausible effects of epigenetics on the emergence of brain network function and dysfunction in adolescence. We discuss how gene-environment interactions, effected by epigenetic mechanisms, might in particular mediate the stress response (itself heavily implicated in the emergence of schizophrenia. Next, we discuss the plausible relevance of this framework for adolescent genetic risk populations, a risk group characterized by vexing and difficult-to-explain heterogeneity. We then discuss how exploring relationships between epigenetics and brain network dysfunction (a strongly validated finding in risk populations can enhance understanding of the relationship between stress, epigenetics and functional neurobiology, and the relevance of this relationship for the eventual emergence of schizophrenia/psychosis. We suggest that these considerations can expand the impact of models such as the sociodevelopmental cognitive model, increasing their explanatory reach. Ultimately, integration of these lines of research may enhance efforts of early identification, intervention and treatment in adolescents at risk for schizophrenia.

  12. Reducing the radiation dose to the eye lens region during CT brain examination: the potential beneficial effect of the combined use of bolus and a bismuth shield

    International Nuclear Information System (INIS)

    Objective: Computed Tomography (CT) is the leading contributor to medical exposure to ionizing radiation. Although the use of CT brain scans for patients with head injuries and convulsions has shown a tremendous growth, it has raised substantial concerns in the general public because of the risk of radiation-induced cataracts: the current available strategies to reduce the radiation dose to the eye lens region are limited. Therefore, the present research project was initiated with the aim of evaluating the potential benefit of the combined use of bolus and a bismuth shield on reducing the radiation dose to the eye lens region during CT brain examination. Materials and methods: We conducted a series of phantom studies to measure the entrance surface dose (ESD) that is delivered to the eye lens region during CT brain examination under the effect of different scanning and shielding setups. Results: Our results indicated, during CT brain examination: (1) a drastic reduction of 92.5% in the ESD to the eye lens region was found when the CT gantry was tilted from 0 deg. (overall ESD = 30.7 mGy) to 30 deg. cranially (overall ESD = 2.4 mGy), and (2) when the CT gantry was positioned at 0 deg. (the common practice in the clinical setting), the setups with the application of a) a bismuth shield, b) a bismuth shield with a face shield (air gap), c) a bismuth shield with bolus, and d) a bismuth shield with bolus and an air gap can result in an acceptable level of image quality with a smaller overall ESD delivered to the eye lens region (overall ESD = 23.2 mGy, 24 mGy, 21 mGy and 19.9 mGy, respectively) than the setup without the bismuth shield applied (overall ESD = 30.7 mGy). Conclusion: When the primary beam scanning through the eye lens region is unavoidable during CT brain examination, the combined use of a bismuth shield with bolus and a face shield is an easy-to-use and inexpensive shielding setup to reduce the radiation dose delivered to the eye lens region while

  13. Evaluating Potential of MODIS-based Indices in Determining “Snow Gone” Stage over Forest-dominant Regions

    Directory of Open Access Journals (Sweden)

    Navdeep S. Sekhon

    2010-05-01

    Full Text Available “Snow gone” (SGN stage is one of the critical variables that describe the start of the official forest fire season in the Canadian Province of Alberta. In this paper, our objective is to evaluate the potential of MODIS-based indices for determining the SGN stage. Those included: (i enhanced vegetation index (EVI, (ii normalized difference water index (NDWI using the shortwave infrared (SWIR spectral bands centered at 1.64 µm (NDWI1.64µm and at 2.13 µm (NDWI2.13µm, and (iii normalized difference snow index (NDSI. These were calculated using the 500 m 8-day gridded MODIS-based composites of surface reflectance data (i.e., MOD09A1 v.005 for the period 2006–08. We performed a qualitative evaluation of these indices over two forest fire prone natural subregions in Alberta (i.e., central mixedwood and lower boreal highlands. In the process, we generated and compared the natural subregion-specific lookout tower sites average: (i temporal trends for each of the indices, and (ii SGN stage using the ground-based observations available from Alberta Sustainable Resource Development. The EVI-values were found to have large uncertainty at the onset of the spring and unable to predict the SGN stages precisely. In terms of NDSI, it showed earlier prediction capabilities. On the contrary, both of the NDWI’s showed distinct pattern (i.e., reached a minimum value before started to increase again during the spring in relation to observed SGN stages. Thus further analysis was carried out to determine the best predictor by comparing the NDWI’s predicted SGN stages with the ground-based observations at all of the individual lookout tower sites (approximately 120 in total across the study area. It revealed that NDWI2.13µm demonstrated better prediction capabilities (i.e., on an average approximately 90% of the observations fell within ±2 periods or ±16 days of deviation in comparison to NDWI1.64µm (i.e., on an average approximately 73% of the

  14. Three tropical seagrasses as potential bio-indicators to trace metals in Xincun Bay, Hainan Island, South China

    Institute of Scientific and Technical Information of China (English)

    LI Lei; HUANG Xiaoping

    2012-01-01

    Concentrations of the trace metals Cu,Cd,Pb,and Zn were measured in seawater,rhizosphere sediments,interstitial water,and the tissues of three tropical species of seagrasses (Thalassia hemprichii,Enhalus acoroides and Cymodocea rotundata) from Xincun Bay of Hainan Island,South China.We analyzed different environmental compartments and the highest concentrations of Pb and Zn were found in the interstitial and seawater.The concentrations of Cd and Zn were significantly higher in blades compared with roots or rhizomes in T.hemprichii and E.acoroides,respectively.A metal pollution index (MPI) demonstrated that sediment,interstitial water,and seagrasses in the sites located nearest anthropogenic sources of pollution had the most abundant metal concentrations.There was obvious seasonal variation of these metals in the three seagrasses with higher concentrations of Cu,Pb and Zn in January and Cd in July.Furthermore,the relationships between metal concentrations in seagrasses and environmental compartments were positively correlated significantly.The bioconcentration factors (BCF) demonstrated that Cd from the tissues of the three seagrasses might be absorbed from the sediment by the roots.However,for C.rotundata,Zn is likely to be derived from the seawater through its blades.Therefore,the blades of T.hemprichii,E.acoroides and C.rotundata are potential bio-indicators to Cd content in sediment,and additionally Zn content (C.rotundata only) in seawater.

  15. Photoplethysmogram intensity ratio: A potential indicator for improving the accuracy of PTT-based cuffless blood pressure estimation.

    Science.gov (United States)

    Ding, Xiao-Rong; Zhang, Yuan-Ting

    2015-01-01

    The most commonly used method for cuffless blood pressure (BP) measurement is using pulse transit time (PTT), which is based on Moens-Korteweg (M-K) equation underlying the assumption that arterial geometries such as the arterial diameter keep unchanged. However, the arterial diameter is dynamic which varies over the cardiac cycle, and it is regulated through the contraction or relaxation of the vascular smooth muscle innervated primarily by the sympathetic nervous system. This may be one of the main reasons that impair the BP estimation accuracy. In this paper, we propose a novel indicator, the photoplethysmogram (PPG) intensity ratio (PIR), to evaluate the arterial diameter change. The deep breathing (DB) maneuver and Valsalva maneuver (VM) were performed on five healthy subjects for assessing parasympathetic and sympathetic nervous activities, respectively. Heart rate (HR), PTT, PIR and BP were measured from the simultaneously recorded electrocardiogram (ECG), PPG, and continuous BP. It was found that PIR increased significantly from inspiration to expiration during DB, whilst BP dipped correspondingly. Nevertheless, PIR changed positively with BP during VM. In addition, the spectral analysis revealed that the dominant frequency component of PIR, HR and SBP, shifted significantly from high frequency (HF) to low frequency (LF), but not obvious in that of PTT. These results demonstrated that PIR can be potentially used to evaluate the smooth muscle tone which modulates arterial BP in the LF range. The PTT-based BP measurement that take into account the PIR could therefore improve its estimation accuracy. PMID:26736283

  16. Colorimetric Detection of Caspase 3 Activity and Reactive Oxygen Derivatives: Potential Early Indicators of Thermal Stress in Corals

    Directory of Open Access Journals (Sweden)

    Mickael Ros

    2016-01-01

    Full Text Available There is an urgent need to develop and implement rapid assessments of coral health to allow effective adaptive management in response to coastal development and global change. There is now increasing evidence that activation of caspase-dependent apoptosis plays a key role during coral bleaching and subsequent mortality. In this study, a “clinical” approach was used to assess coral health by measuring the activity of caspase 3 using a commercial kit. This method was first applied while inducing thermal bleaching in two coral species, Acropora millepora and Pocillopora damicornis. The latter species was then chosen to undergo further studies combining the detection of oxidative stress-related compounds (catalase activity and glutathione concentrations as well as caspase activity during both stress and recovery phases. Zooxanthellae photosystem II (PSII efficiency and cell density were measured in parallel to assess symbiont health. Our results demonstrate that the increased caspase 3 activity in the coral host could be detected before observing any significant decrease in the photochemical efficiency of PSII in the algal symbionts and/or their expulsion from the host. This study highlights the potential of host caspase 3 and reactive oxygen species scavenging activities as early indicators of stress in individual coral colonies.

  17. Brain wave correlates of attentional states: Event related potentials and quantitative EEG analysis during performance of cognitive and perceptual tasks

    Science.gov (United States)

    Freeman, Frederick G.

    1993-01-01

    presented target stimulus. In addition to the task requirements, irrelevant tones were presented in the background. Research has shown that even though these stimuli are not attended, ERP's to them can still be elicited. The amplitude of the ERP waves has been shown to change as a function of a person's level of alertness. ERP's were also collected and analyzed for the target stimuli for each task. Brain maps were produced based on the ERP voltages for the different stimuli. In addition to the ERP's, a quantitative EEG (QEEG) was performed on the data using a fast Fourier technique to produce a power spectral analysis of the EEG. This analysis was conducted on the continuous EEG while the subjects were performing the tasks. Finally, a QEEG was performed on periods during the task when subjects indicated that they were in an altered state of awareness. During the tasks, subjects were asked to indicate by pressing a button when they realized their level of task awareness had changed. EEG epochs were collected for times just before and just after subjects made this reponse. The purpose of this final analysis was to determine whether or not subjective indices of level of awareness could be correlated with different patterns of EEG.

  18. Working memory maintenance contributes to long-term memory formation: evidence from slow event-related brain potentials.

    Science.gov (United States)

    Khader, Patrick; Ranganath, Charan; Seemüller, Anna; Rösler, Frank

    2007-09-01

    Behavioral research has led to conflicting views regarding the relationship between working memory (WM) maintenance and long-term memory (LTM) formation. We used slow event-related brain potentials to investigate the degree to which neural activity during WM maintenance is associated with successful LTM formation. Participants performed a WM task with objects and letter strings, followed by a surprise LTM test. Slow potentials were found to be more negative over the parietal and occipital cortex for objects and over the left frontal cortex for letter strings during WM maintenance. Within each category, they were enhanced for items that were subsequently successfully remembered. These effects were topographically distinct, with maximum effects at those electrodes that showed the maximum negativity during WM maintenance in general. Together, these results are strongly consistent with the ideas that WM maintenance contributes to LTM formation and that this may occur through strengthening of stimulus-specific cortical memory traces. PMID:17993207

  19. Single-trial detection of visual evoked potentials by common spatial patterns and wavelet filtering for brain-computer interface.

    Science.gov (United States)

    Tu, Yiheng; Huang, Gan; Hung, Yeung Sam; Hu, Li; Hu, Yong; Zhang, Zhiguo

    2013-01-01

    Event-related potentials (ERPs) are widely used in brain-computer interface (BCI) systems as input signals conveying a subject's intention. A fast and reliable single-trial ERP detection method can be used to develop a BCI system with both high speed and high accuracy. However, most of single-trial ERP detection methods are developed for offline EEG analysis and thus have a high computational complexity and need manual operations. Therefore, they are not applicable to practical BCI systems, which require a low-complexity and automatic ERP detection method. This work presents a joint spatial-time-frequency filter that combines common spatial patterns (CSP) and wavelet filtering (WF) for improving the signal-to-noise (SNR) of visual evoked potentials (VEP), which can lead to a single-trial ERP-based BCI.

  20. Correction: Cecotti, H. and Rivet, B. Subject Combination and Electrode Selection in Cooperative Brain-Computer Interface Based on Event Related Potentials. Brain Sci. 2014, 4, 335–355

    Directory of Open Access Journals (Sweden)

    Hubert Cecotti

    2014-09-01

    Full Text Available The authors wish to make the following correction to this paper (Cecotti, H.; Rivet, B. Subject Combination and Electrode Selection in Cooperative Brain-Computer Interface Based on Event Related Potentials. Brain Sci. 2014, 4, 335–355: Due to an internal error, the reference numbers in the original published paper were not shown, and the error was not due to the authors. The former main text should be replaced as below.

  1. Characterization of Brain-Penetrant Pyrimidine-Containing Molecules with Differential Microtubule-Stabilizing Activities Developed as Potential Therapeutic Agents for Alzheimer's Disease and Related Tauopathies.

    Science.gov (United States)

    Kovalevich, Jane; Cornec, Anne-Sophie; Yao, Yuemang; James, Michael; Crowe, Alexander; Lee, Virginia M-Y; Trojanowski, John Q; Smith, Amos B; Ballatore, Carlo; Brunden, Kurt R

    2016-05-01

    The microtubule (MT)-stabilizing protein tau disengages from MTs and forms intracellular inclusions known as neurofibrillary tangles in Alzheimer's disease and related tauopathies. Reduced tau binding to MTs in tauopathies may contribute to neuronal dysfunction through decreased MT stabilization and disrupted axonal transport. Thus, the introduction of brain-penetrant MT-stabilizing compounds might normalize MT dynamics and axonal deficits in these disorders. We previously described a number of phenylpyrimidines and triazolopyrimidines (TPDs) that induce tubulin post-translational modifications indicative of MT stabilization. We now further characterize the biologic properties of these small molecules, and our results reveal that these compounds can be divided into two general classes based on the cellular response they evoke. One group composed of the phenylpyrimidines and several TPD examples showed a bell-shaped concentration-response effect on markers of MT stabilization in cellular assays. Moreover, these compounds induced proteasome-dependent degradation of α- and β-tubulin and caused altered MT morphology in both dividing cells and neuron cultures. In contrast, a second group comprising a subset of TPD molecules (TPD+) increased markers of stable MTs in a concentration-dependent manner in dividing cells and in neurons without affecting total tubulin levels or disrupting MT architecture. Moreover, an example TPD+ compound was shown to increase MTs in a neuron culture model with induced tau hyperphosphorylation and associated MT deficits. Several TPD+ compounds were shown to be both brain penetrant and orally bioavailable, and a TPD+ example increased MT stabilization in the mouse brain, making these compounds potential candidate therapeutics for neurodegenerative tauopathies such as Alzheimer's disease. PMID:26980057

  2. Steady-state evoked potentials to study the processing of tactile and nociceptive somatosensory input in the human brain.

    Science.gov (United States)

    Colon, E; Legrain, V; Mouraux, A

    2012-10-01

    The periodic presentation of a sensory stimulus induces, at certain frequencies of stimulation, a sustained electroencephalographic response of corresponding frequency, known as steady-state evoked potentials (SS-EP). In visual, auditory and vibrotactile modalities, studies have shown that SS-EP reflect mainly activity originating from early, modality-specific sensory cortices. Furthermore, it has been shown that SS-EP have several advantages over the recording of transient event-related brain potentials (ERP), such as a high signal-to-noise ratio, a shorter time to obtain reliable signals, and the capacity to frequency-tag the cortical activity elicited by concurrently presented sensory stimuli. Recently, we showed that SS-EP can be elicited by the selective activation of skin nociceptors and that nociceptive SS-EP reflect the activity of a population of neurons that is spatially distinct from the somatotopically-organized population of neurons underlying vibrotactile SS-EP. Hence, the recording of SS-EP offers a unique opportunity to study the cortical representation of nociception and touch in humans, and to explore their potential crossmodal interactions. Here, (1) we review available methods to achieve the rapid periodic stimulation of somatosensory afferents required to elicit SS-EP, (2) review previous studies that have characterized vibrotactile and nociceptive SS-EP, (3) discuss the nature of the recorded signals and their relationship with transient event-related potentials and (4) outline future perspectives and potential clinical applications of this technique.

  3. Bioavailability and soil-to-plant transfer factors as indicators of potentially toxic element contamination in agricultural soils

    Energy Technology Data Exchange (ETDEWEB)

    Adamo, Paola, E-mail: paola.adamo@unina.it [Dipartimento di Agraria, Università di Napoli Federico II, via Università 100, 80055 Portici (Italy); Iavazzo, Pietro [Dipartimento di Agraria, Università di Napoli Federico II, via Università 100, 80055 Portici (Italy); Albanese, Stefano [Dipartimento di Scienze della Terra, dell' Ambiente e delle Risorse, Università di Napoli Federico II, Via Mezzocannone 8, 80134 Napoli (Italy); Agrelli, Diana [Dipartimento di Agraria, Università di Napoli Federico II, via Università 100, 80055 Portici (Italy); De Vivo, Benedetto; Lima, Annamaria [Dipartimento di Scienze della Terra, dell' Ambiente e delle Risorse, Università di Napoli Federico II, Via Mezzocannone 8, 80134 Napoli (Italy)

    2014-12-01

    Soil pollution in agricultural lands poses a serious threat to food safety, and suggests the need for consolidated methods providing advisory indications for soil management and crop production. In this work, the three-step extraction procedure developed by the EU Measurement and Testing Programme and two soil-to-plant transfer factors (relative to total and bioavailable concentration of elements in soil) were applied on polluted agricultural soils from southern Italy to obtain information on the retention mechanisms of metals in soils and on their level of translocation to edible vegetables. The study was carried out in the Sarno river plain of Campania, an area affected by severe environmental degradation potentially impacting the health of those consuming locally produced vegetables. Soil samples were collected in 36 locations along the two main rivers flowing into the plain. In 11 sites, lettuce plants were collected at the normal stage of consumption. According to Italian environmental law governing residential soils, and on the basis of soil background reference values for the study area, we found diffuse pollution by Be, Sn and Tl, of geogenic origin, Cr and Cu from anthropogenic sources such as tanneries and intensive agriculture, and more limited pollution by Pb, Zn and V. It was found that metals polluting soils as a result of human activities were mainly associated to residual, oxidizable and reducible phases, relatively immobile and only potentially bioavailable to plants. By contrast, the essential elements Zn and Cu showed a tendency to become more readily mobile and bioavailable as their total content in soil increased and were more easily transported to the edible parts of lettuce than other pollutants. According to our results, current soil pollution in the studied area does not affect the proportion of metals taken up by lettuce plants and there is a limited health risk incurred. - Highlights: • Soil pollution in an intensively farmed area of

  4. Bioavailability and soil-to-plant transfer factors as indicators of potentially toxic element contamination in agricultural soils

    International Nuclear Information System (INIS)

    Soil pollution in agricultural lands poses a serious threat to food safety, and suggests the need for consolidated methods providing advisory indications for soil management and crop production. In this work, the three-step extraction procedure developed by the EU Measurement and Testing Programme and two soil-to-plant transfer factors (relative to total and bioavailable concentration of elements in soil) were applied on polluted agricultural soils from southern Italy to obtain information on the retention mechanisms of metals in soils and on their level of translocation to edible vegetables. The study was carried out in the Sarno river plain of Campania, an area affected by severe environmental degradation potentially impacting the health of those consuming locally produced vegetables. Soil samples were collected in 36 locations along the two main rivers flowing into the plain. In 11 sites, lettuce plants were collected at the normal stage of consumption. According to Italian environmental law governing residential soils, and on the basis of soil background reference values for the study area, we found diffuse pollution by Be, Sn and Tl, of geogenic origin, Cr and Cu from anthropogenic sources such as tanneries and intensive agriculture, and more limited pollution by Pb, Zn and V. It was found that metals polluting soils as a result of human activities were mainly associated to residual, oxidizable and reducible phases, relatively immobile and only potentially bioavailable to plants. By contrast, the essential elements Zn and Cu showed a tendency to become more readily mobile and bioavailable as their total content in soil increased and were more easily transported to the edible parts of lettuce than other pollutants. According to our results, current soil pollution in the studied area does not affect the proportion of metals taken up by lettuce plants and there is a limited health risk incurred. - Highlights: • Soil pollution in an intensively farmed area of

  5. Geothermal systems in volcanic arcs: Volcanic characteristics and surface manifestations as indicators of geothermal potential and favorability worldwide

    Science.gov (United States)

    Stelling, P.; Shevenell, L.; Hinz, N.; Coolbaugh, M.; Melosh, G.; Cumming, W.

    2016-09-01

    This paper brings a global perspective to volcanic arc geothermal assessments by evaluating trends and correlations of volcanic characteristic and surface manifestation data from world power production sites in subduction zone volcanic settings. The focus of the work was to evaluate volcanic centers individually and as a group in these arcs by correlating various geologic characteristics with known potential to host electricity grade geothermal systems at the volcanic centers. A database was developed that describes key geologic factors expected to be indicative of productive geothermal systems in a global training set, which includes all 74 subduction zone volcanic centers world-wide with current or proven power production capability. Importantly, this data set only contains data from subduction zone volcanoes and contains no negative cases, limiting the populations of any statistical groups. Regardless, this is the most robust geothermal benchmark training set for magmatic-heated systems to date that has been made public. The work reported here is part of a larger project that included data collection, evaluation, correlations and weightings, fairway and favorability modeling and mapping, prediction of blind systems, and uncertainty analysis to estimate errors associated with model predictions. This first paper describes volcano characteristics, compositions and eruption ages and trends along with surface manifestation observations and temperatures as they relate to known power producing systems. Our findings show a strong correlation between the presence and size of active flank fumarole areas and installed power production. Additionally, the majority of volcanic characteristics, including long-held anecdotal correlations related to magmatic composition or size, have limited to no correlation with power production potential. Notable exceptions are correlations between greater power yield from geothermal systems associated with older (Pleistocene) caldera systems

  6. Cannabinoid receptors in brain: pharmacogenetics, neuropharmacology, neurotoxicology, and potential therapeutic applications.

    Science.gov (United States)

    Onaivi, Emmanuel S

    2009-01-01

    Much progress has been achieved in cannabinoid research. A major breakthrough in marijuana-cannabinoid research has been the discovery of a previously unknown but elaborate endogenous endocannabinoid system (ECS), complete with endocannabinoids and enzymes for their biosynthesis and degradation with genes encoding two distinct cannabinoid (CB1 and CB2) receptors (CBRs) that are activated by endocannabinoids, cannabinoids, and marijuana use. Physical and genetic localization of the CBR genes CNR1 and CNR2 have been mapped to chromosome 6 and 1, respectively. A number of variations in CBR genes have been associated with human disorders including osteoporosis, attention deficit hyperactivity disorder (ADHD), posttraumatic stress disorder (PTSD), drug dependency, obesity, and depression. Other family of lipid receptors including vanilloid (VR1) and lysophosphatidic acid (LPA) receptors appear to be related to the CBRs at the phylogenetic level. The ubiquitous abundance and differential distribution of the ECS in the human body and brain along with the coupling to many signal transduction pathways may explain the effects in most biological system and the myriad behavioral effects associated with smoking marijuana. The neuropharmacological and neuroprotective features of phytocannabinoids and endocannabinoid associated neurogenesis have revealed roles for the use of cannabinoids in neurodegenerative pathologies with less neurotoxicity. The remarkable progress in understanding the biological actions of marijuana and cannabinoids have provided much richer results than previously appreciated cannabinoid genomics and raised a number of critical issues on the molecular mechanisms of cannabinoid induced behavioral and biochemical alterations. These advances will allow specific therapeutic targeting of the different components of the ECS in health and disease. This review focuses on these recent advances in cannabinoid genomics and the surprising new fundamental roles that the

  7. Differential Expression of FosB Proteins and Potential Target Genes in Select Brain Regions of Addiction and Depression Patients.

    Science.gov (United States)

    Gajewski, Paula A; Turecki, Gustavo; Robison, Alfred J

    2016-01-01

    Chronic exposure to stress or drugs of abuse has been linked to altered gene expression throughout the body, and changes in gene expression in discrete brain regions are thought to underlie many psychiatric diseases, including major depressive disorder and drug addiction. Preclinical models of these disorders have provided evidence for mechanisms of this altered gene expression, including transcription factors, but evidence supporting a role for these factors in human patients has been slow to emerge. The transcription factor ΔFosB is induced in the prefrontal cortex (PFC) and hippocampus (HPC) of rodents in response to stress or cocaine, and its expression in these regions is thought to regulate their "top down" control of reward circuitry, including the nucleus accumbens (NAc). Here, we use biochemistry to examine the expression of the FosB family of transcription factors and their potential gene targets in PFC and HPC postmortem samples from depressed patients and cocaine addicts. We demonstrate that ΔFosB and other FosB isoforms are downregulated in the HPC but not the PFC in the brains of both depressed and addicted individuals. Further, we show that potential ΔFosB transcriptional targets, including GluA2, are also downregulated in the HPC but not PFC of cocaine addicts. Thus, we provide the first evidence of FosB gene expression in human HPC and PFC in these psychiatric disorders, and in light of recent findings demonstrating the critical role of HPC ΔFosB in rodent models of learning and memory, these data suggest that reduced ΔFosB in HPC could potentially underlie cognitive deficits accompanying chronic cocaine abuse or depression. PMID:27494187

  8. Synthesis characterization and biological evaluation of a novel mixed ligand 99mTc complex as potential brain imaging agent

    International Nuclear Information System (INIS)

    One approach in the design of neutral oxotechnetium complexes is based on the simultaneous substitution of a tridentate dianionic ligand and a monodentate monoanionic coligand on a [Tc(V)O]+3 precursor. Following this ''mixed ligand'' concept, a novel 99mTc complex with N,N-bis(2-mercaptoethyl)-N'N'-diethylethylenediamine as ligand and 1-octanethiol as coligand is prepared and evaluated as potential brain radiopharmaceutical. Preparation of the complex at tracer level was accomplished by using 99mTc-glucoheptonate as precursor. The substitution was optimized and a coligand/ligand ratio of 5 was selected. Under this conditions the labeling yield was over 80% and a major product (with radiochemical purity > 80%) was isolated by HPLC methods and used for biological evaluation. Chemical characterization at carrier level was developed using the corresponding rhenium complex as structural model. The Re complex was also prepared by substitution method and isolated as a crystalline product. The crystals were characterized by UV-vis and IR spectra and elemental analysis. Results were consistent with the expected ReOLC structure. X ray crystallographic study demonstrated that the complex adopts a distorted trigonal bipyramidal geometry. The basal plane is defined by the SS atoms of the ligand and the oxo group, while the N of the ligand and the S of the colligand occupy the two apical positions. All sulphur atoms underwent ionization leading to the formation of a neutral compound. 99Tc complex was also prepared. Although it was not isolated due to the small amount of reagents employed, the HPLC profile was identical to the one observed for the rhenium complex suggesting the same chemical structure. Biodistribution in mice demonstrated early brain uptake, fast blood clearance, excretion through hepatobiliary system and a brain/blood ratio that increased significantly with time. (author)

  9. Hyperbaric oxygen therapy as a potential treatment for post-traumatic stress disorder associated with traumatic brain injury

    Science.gov (United States)

    Eve, David J; Steele, Martin R; Sanberg, Paul R; Borlongan, Cesar V

    2016-01-01

    Traumatic brain injury (TBI) describes the presence of physical damage to the brain as a consequence of an insult and frequently possesses psychological and neurological symptoms depending on the severity of the injury. The recent increased military presence of US troops in Iraq and Afghanistan has coincided with greater use of improvised exploding devices, resulting in many returning soldiers suffering from some degree of TBI. A biphasic response is observed which is first directly injury-related, and second due to hypoxia, increased oxidative stress, and inflammation. A proportion of the returning soldiers also suffer from post-traumatic stress disorder (PTSD), and in some cases, this may be a consequence of TBI. Effective treatments are still being identified, and a possible therapeutic candidate is hyperbaric oxygen therapy (HBOT). Some clinical trials have been performed which suggest benefits with regard to survival and disease severity of TBI and/or PTSD, while several other studies do not see any improvement compared to a possibly poorly controlled sham. HBOT has been shown to reduce apoptosis, upregulate growth factors, promote antioxidant levels, and inhibit inflammatory cytokines in animal models, and hence, it is likely that HBOT could be advantageous in treating at least the secondary phase of TBI and PTSD. There is some evidence of a putative prophylactic or preconditioning benefit of HBOT exposure in animal models of brain injury, and the optimal time frame for treatment is yet to be determined. HBOT has potential side effects such as acute cerebral toxicity and more reactive oxygen species with long-term use, and therefore, optimizing exposure duration to maximize the reward and decrease the detrimental effects of HBOT is necessary. This review provides a summary of the current understanding of HBOT as well as suggests future directions including prophylactic use and chronic treatment. PMID:27799776

  10. Influence of P300 latency jitter on event related potential-based brain-computer interface performance

    Science.gov (United States)

    Aricò, P.; Aloise, F.; Schettini, F.; Salinari, S.; Mattia, D.; Cincotti, F.

    2014-06-01

    Objective. Several ERP-based brain-computer interfaces (BCIs) that can be controlled even without eye movements (covert attention) have been recently proposed. However, when compared to similar systems based on overt attention, they displayed significantly lower accuracy. In the current interpretation, this is ascribed to the absence of the contribution of short-latency visual evoked potentials (VEPs) in the tasks performed in the covert attention modality. This study aims to investigate if this decrement (i) is fully explained by the lack of VEP contribution to the classification accuracy; (ii) correlates with lower temporal stability of the single-trial P300 potentials elicited in the covert attention modality. Approach. We evaluated the latency jitter of P300 evoked potentials in three BCI interfaces exploiting either overt or covert attention modalities in 20 healthy subjects. The effect of attention modality on the P300 jitter, and the relative contribution of VEPs and P300 jitter to the classification accuracy have been analyzed. Main results. The P300 jitter is higher when the BCI is controlled in covert attention. Classification accuracy negatively correlates with jitter. Even disregarding short-latency VEPs, overt-attention BCI yields better accuracy than covert. When the latency jitter is compensated offline, the difference between accuracies is not significant. Significance. The lower temporal stability of the P300 evoked potential generated during the tasks performed in covert attention modality should be regarded as the main contributing explanation of lower accuracy of covert-attention ERP-based BCIs.

  11. [Effect of the novel dipeptide nootropic agent noopept and its metabolite cyclo-L-prolylglycine on the transcallosal evoked potential in the rat brain].

    Science.gov (United States)

    Molodavkin, G M; Borlikova, G G; Voronina, T A; Gudasheva, T A; Ostrovskaia, R U; Tushmalova, N A; Seredenin, S B

    2002-01-01

    The effect of new nootropic dipeptides--noopept (N-phenylacetyl-L-prolylglycine, GVS-111) and its metabolite (cyclo-L-prolylglycine)--and a standard nootrope piracetam on the transcallosal evoked potential (TEP) in rat brain was studied. In the dose range from 150 to 300 mg/kg, piracetam increased the TEP amplitude, which exhibited a maximum after 1.5-2 h and then gradually decreased. Both noopept and cyclo-L-prolylglycine also increased the TEP amplitude, which attained a plateau and retained this level over the entire observation time (above 3.5 h). All the nootropes studied increased both components of the evoked potential. Piracetam and cyclo-L-prolylglycine led to an approximately equal increase in both waves, while noopept induced a somewhat greater increase in the negative TEP wave amplitude. It is suggested that the positive effect of noopept and cyclo-L-prolylglycine upon the interhemispheric signal transfer (indicated by the improved transcallosal response) can be considered as a potential neurophysiological basis for a positive drug influence on the behavioral level. PMID:12109288

  12. Low-molecular-mass peptides from the venom of the Amazonian viper Bothrops atrox protect against brain mitochondrial swelling in rat: potential for neuroprotection.

    Science.gov (United States)

    Martins, N M; Ferreira, D A S; Carvalho Rodrigues, M A; Cintra, A C O; Santos, N A G; Sampaio, S V; Santos, A C

    2010-08-01

    The neurodegenerative diseases are important causes of morbidity and mortality in Western countries. Common mechanisms of toxicity involving mitochondrial damage have been suggested; however, a definitive treatment has not yet been found. Therefore, there has been great interest in the development of mitochondria-targeted protective compounds for the treatment of neuropathies. Animal toxins represent a promising source of new molecules with neuroprotective activity and potential to originate new drugs. We present here the effects of a low-molecular-mass peptides fraction (Ba-V) from Bothrops atrox snake venom, on rat brain mitochondrial function. Ba-V did not induce the mitochondrial swelling and moreover, was as effective as cyclosporin A (CsA) to inhibit the calcium/phosphate-induced swelling, which indicates its potential to prevent the mitochondrial permeability transition (MPT). The membrane electrochemical potential, the oxygen consumption during states-3 and -4 respirations as well as the respiratory control ratio (RCR) were not affected by Ba-V. Additionally, Ba-V did not induce reactive oxygen species (ROS) generation. Interestingly, Ba-V did not protect against the generation of ROS induced by t-BOH, which suggests a protection mechanism other than ROS scavenging. Given the important role of the mitochondrial damage and, more specifically, of MPT, in the development of neuropathies, Ba-V might be useful in the future strategies for the treatment of these diseases. PMID:20338188

  13. The effect of the physical presence of co-players on perceived ostracism and event-related brain potentials in the cyberball paradigm.

    Directory of Open Access Journals (Sweden)

    Sarah Weschke

    Full Text Available The affective and cognitive mechanisms elicited by the experience of social exclusion-or ostracism-have recently been explored using behavioral and neurocognitive methods. Most of the studies took advantage of the Cyberball paradigm, a virtual ball tossing game with presumed co-players connected via the internet. Consistent behavioral findings indicate that exclusion obviously threatens fundamental social needs (belonging, self-esteem, meaningful existence, and control and lowers mood. In this study, we followed the question whether the credibility of the setting affects the processing of social exclusion. In contrast to a control group (standard Cyberball setup, co-players were physically present in an experimental group. Although the credibility of the virtual ball tossing game was significantly enhanced in the experimental group, self-reported negative mood and need threat were not enhanced compared to the control group. Event-related brain potentials (ERPs, however, indicated a differential processing of social exclusion. The N2 amplitude triggered by occasional ball receptions was significantly reduced in the experimental group. This effect was restricted for an early time range (130-210 ms, and did not extend to the following P3 components. The ERP effect in the N2 time range can be related to a differential social reward processing in ostracism if co-players are physically present. The lack of a corresponding correlate in the behavioral data indicates that some facets of ostracism processing are not covered by questionnaire data.

  14. Reliability-based automatic repeat request for short code modulation visual evoked potentials in brain computer interfaces.

    Science.gov (United States)

    Sato, Jun-Ichi; Washizawa, Yoshikazu

    2015-08-01

    We propose two methods to improve code modulation visual evoked potential brain computer interfaces (cVEP BCIs). Most of BCIs average brain signals from several trials in order to improve the classification performance. The number of averaging defines the trade-off between input speed and accuracy, and the optimal averaging number depends on individual, signal acquisition system, and so forth. Firstly, we propose a novel dynamic method to estimate the averaging number for cVEP BCIs. The proposed method is based on the automatic repeat request (ARQ) that is used in communication systems. The existing cVEP BCIs employ rather longer code, such as 63-bit M-sequence. The code length also defines the trade-off between input speed and accuracy. Since the reliability of the proposed BCI can be controlled by the proposed ARQ method, we introduce shorter codes, 32-bit M-sequence and the Kasami-sequence. Thanks to combine the dynamic averaging number estimation method and the shorter codes, the proposed system exhibited higher information transfer rate compared to existing cVEP BCIs.

  15. Lateral ventricular cerebrospinal fluid diffusivity as a potential neuroimaging marker of brain temperature in multiple sclerosis: a hypothesis and implications.

    Science.gov (United States)

    Hasan, Khader M; Lincoln, John A; Nelson, Flavia M; Wolinsky, Jerry S; Narayana, Ponnada A

    2015-04-01

    In this retrospective study we tested the hypothesis that the net effect of impaired electrical conduction and therefore increased heat dissipation in multiple sclerosis (MS) results in elevated lateral ventricular (LV) cerebrospinal fluid (CSF) diffusivity as a measure of brain temperature estimated in vivo using diffusion tensor imaging (DTI). We used validated DTI-based segmentation methods to obtain normalized LV-CSF volume and its corresponding CSF diffusivity in 108 MS patients and 103 healthy controls in the age range of 21-63 years. The LV CSF diffusivity was ~2% higher in MS compared to controls that correspond to a temperature rise of ~1°C that could not be explained by changes in the CSF viscosity due to altered CSF protein content in MS. The LV diffusivity decreased with age in healthy controls (r=-0.29; p=0.003), but not in MS (r=0.15; p=0.11), possibly related to MS pathology. Age-adjusted LV diffusivity increased with lesion load (r=0.518; p=1×10(-8)). Our data suggest that the total brain lesion load is the primary contributor to the increase in LV CSF diffusivity in MS. These findings suggest that LV diffusivity is a potential in vivo biomarker of the mismatch between heat generation and dissipation in MS. We also discuss limitations and possible confounders. PMID:25485790

  16. A brain-computer interface controlled auditory event-related potential (p300) spelling system for locked-in patients.

    Science.gov (United States)

    Kübler, Andrea; Furdea, Adrian; Halder, Sebastian; Hammer, Eva Maria; Nijboer, Femke; Kotchoubey, Boris

    2009-03-01

    Using brain-computer interfaces (BCI) humans can select letters or other targets on a computer screen without any muscular involvement. An intensively investigated kind of BCI is based on the recording of visual event-related brain potentials (ERP). However, some severely paralyzed patients who need a BCI for communication have impaired vision or lack control of gaze movement, thus making a BCI depending on visual input no longer feasible. In an effort to render the ERP-BCI usable for this group of patients, the ERP-BCI was adapted to auditory stimulation. Letters of the alphabet were assigned to cells in a 5 x 5 matrix. Rows of the matrix were coded with numbers 1 to 5, and columns with numbers 6 to 10, and the numbers were presented auditorily. To select a letter, users had to first select the row and then the column containing the desired letter. Four severely paralyzed patients in the end-stage of a neurodegenerative disease were examined. All patients performed above chance level. Spelling accuracy was significantly lower with the auditory system as compared with a similar visual system. Patients reported difficulties in concentrating on the task when presented with the auditory system. In future studies, the auditory ERP-BCI should be adjusted by taking into consideration specific features of severely paralyzed patients, such as reduced attention span. This adjustment in combination with more intensive training will show whether an auditory ERP-BCI can become an option for visually impaired patients. PMID:19351359

  17. Tetrahydrocannabinol Induces Brain Mitochondrial Respiratory Chain Dysfunction and Increases Oxidative Stress: A Potential Mechanism Involved in Cannabis-Related Stroke

    Directory of Open Access Journals (Sweden)

    Valérie Wolff

    2015-01-01

    Full Text Available Cannabis has potential therapeutic use but tetrahydrocannabinol (THC, its main psychoactive component, appears as a risk factor for ischemic stroke in young adults. We therefore evaluate the effects of THC on brain mitochondrial function and oxidative stress, key factors involved in stroke. Maximal oxidative capacities Vmax (complexes I, III, and IV activities, Vsucc (complexes II, III, and IV activities, Vtmpd (complex IV activity, together with mitochondrial coupling (Vmax/V0, were determined in control conditions and after exposure to THC in isolated mitochondria extracted from rat brain, using differential centrifugations. Oxidative stress was also assessed through hydrogen peroxide (H2O2 production, measured with Amplex Red. THC significantly decreased Vmax (−71%; P<0.0001, Vsucc (−65%; P<0.0001, and Vtmpd (−3.5%; P<0.001. Mitochondrial coupling (Vmax/V0 was also significantly decreased after THC exposure (1.8±0.2 versus 6.3±0.7; P<0.001. Furthermore, THC significantly enhanced H2O2 production by cerebral mitochondria (+171%; P<0.05 and mitochondrial free radical leak was increased from 0.01±0.01 to 0.10±0.01% (P<0.001. Thus, THC increases oxidative stress and induces cerebral mitochondrial dysfunction. This mechanism may be involved in young cannabis users who develop ischemic stroke since THC might increase patient’s vulnerability to stroke.

  18. Technetium 99 m spiperone dithiocarbamate study as a potential agent for brain pathologies diagnosis related to D 2 dopamine receptors

    International Nuclear Information System (INIS)

    Psycho-pharmacology has been discovering much about the D 2 dopamine receptors and their interrelationship to brain pathologies such as Parkinson's Disease, Schizophrenia and Huntington Disease. Those biological receptors have got affinity with dopamine endogenous agent, so that they complex and, in non pathological individuals, the biological receptors contribute to bring the levels of dopamine and free acetylcholine into equilibrium. The D 2 antagonistic psychotropic agents because of having got strong affinity with those receptors, have been being transformed into radiopharmaceuticals to diagnose these pathological disease of Central Nervous System. The Spiperone Dithiocarbamate complex studied by us, is a potential diagnosis agent because of being highly lipo-soluble and having close relationship with D 2 receptors. Besides, it is a photon emitter, allowing the use of SPECT (Single Photon Emission Computed Tomography) technique which is economically less expensive if compared to the PET (Positron Emission Tomography) technique. The Spiperone Dithiocarbamate (SPDC) is synthesized from Spiperone and its complexation with Technetium-99 m has been prepared with its reaction parameters after being studied and improved. The SPDC-99m Tc complex biological distribution have made in Wistar rats and the uptake of spleen, heart, liver stomach, lung, kidney, blood, intestine and brain have been resolved. The plasmatic clearance curve has been based on Wistar rats data and the know-how of the kit (for label SPDC with Tc) has been achieved. (author). 5 figs, 4 tabs

  19. How Children Process Over-Regularizations: Evidence from Event-Related Brain Potentials

    Science.gov (United States)

    Clahsen, Harald; Luck, Monika; Hahne, Anja

    2007-01-01

    This study examines the mental processes involved in children's on-line recognition of inflected word forms using event-related potentials (ERPs). Sixty children in three age groups (20 six- to seven-year-olds, 20 eight- to nine-year-olds, 20 eleven- to twelve-year-olds) and 23 adults (tested in a previous study) listened to sentences containing…

  20. Brain Games as a Potential Nonpharmaceutical Alternative for the Treatment of ADHD

    Science.gov (United States)

    Wegrzyn, Stacy C.; Hearrington, Doug; Martin, Tim; Randolph, Adriane B.

    2013-01-01

    Attention deficit hyperactivity disorder (ADHD) is the most commonly diagnosed childhood neurobehavioral disorder, affecting approximately 5.5 million children, of which approximately 66% take ADHD medication daily. This study investigated a potential nonpharmaceutical alternative to address the academic engagement of 5th through 11th grade…

  1. Cortical evoked potential and extracellular K+ and H+ at critical levels of brain ischemia

    DEFF Research Database (Denmark)

    Astrup, J; Symon, L; Branston, N M;

    1977-01-01

    + as well as evoked potential were made in the baboon neocortex. Reductions in blood flow were obtained by occlusion of the middle cerebral artery and depression beyond the ischemic threshold of electrical function achieved by a reduction of systemic blood pressure which, in the ischemic zones, changed...

  2. A face-selective ventral occipito-temporal map of the human brain with intracerebral potentials.

    Science.gov (United States)

    Jonas, Jacques; Jacques, Corentin; Liu-Shuang, Joan; Brissart, Hélène; Colnat-Coulbois, Sophie; Maillard, Louis; Rossion, Bruno

    2016-07-12

    Human neuroimaging studies have identified a network of distinct face-selective regions in the ventral occipito-temporal cortex (VOTC), with a right hemispheric dominance. To date, there is no evidence for this hemispheric and regional specialization with direct measures of brain activity. To address this gap in knowledge, we recorded local neurophysiological activity from 1,678 contact electrodes implanted in the VOTC of a large group of epileptic patients (n = 28). They were presented with natural images of objects at a rapid fixed rate (six images per second: 6 Hz), with faces interleaved as every fifth stimulus (i.e., 1.2 Hz). High signal-to-noise ratio face-selective responses were objectively (i.e., exactly at the face stimulation frequency) identified and quantified throughout the whole VOTC. Face-selective responses were widely distributed across the whole VOTC, but also spatially clustered in specific regions. Among these regions, the lateral section of the right middle fusiform gyrus showed the largest face-selective response by far, offering, to our knowledge, the first supporting evidence of two decades of neuroimaging observations with direct neural measures. In addition, three distinct regions with a high proportion of face-selective responses were disclosed in the right ventral anterior temporal lobe, a region that is undersampled in neuroimaging because of magnetic susceptibility artifacts. A high proportion of contacts responding only to faces (i.e., "face-exclusive" responses) were found in these regions, suggesting that they contain populations of neurons involved in dedicated face-processing functions. Overall, these observations provide a comprehensive mapping of visual category selectivity in the whole human VOTC with direct neural measures. PMID:27354526

  3. Spatiotemporal distribution of δ(13)CCO2 in a shallow cave and its potential use as indicator of anthropic pressure.

    Science.gov (United States)

    Gázquez, Fernando; Quindós-Poncela, Luis; Sainz-Fernández, Carlos; Fernández-Villar, Alicia; Fuente-Merino, Ismael; Celaya-Gonzalez, Santiago

    2016-09-15

    This study deals with the spatiotemporal dynamics of CO2 and its isotopic composition (δ(13)CCO2) in the atmosphere of Altamira Cave (northern Spain) over two annual cycles. In general terms, the cavity shows two distinct ventilation modes, acting as a CO2 reservoir from October to May (recharge stage), while actively exchanging gases with the outside atmosphere between July and September (discharge stage). In recharge mode, the in-cave air shows higher and relatively homogeneous CO2 values (3332 ± 521 ppm) with lower δ(13)CCO2 (-23.2 ± 0.4‰). In contrast, during the discharge stage, the CO2 concentrations are lower and relatively more variable (1383 ± 435 ppm) and accompanied by higher δ(13)CCO2 (up to -12‰). This seasonal pattern is controlled by the distinct rates of exchange of air masses with the external atmosphere through the annual cycle, as well as by changes in the production of CO2 in the soil and natural fluctuations in the concentration of dissolved inorganic carbon transported by drip water into the cave. In contrast to the interpretations of previous studies in Altamira Cave, no local air intakes into the deepest cave sections were flagged by our δ(13)C measurements. This finding is also supported by analyses of CO2 and (222)Rn in air, density of airborne particles and air temperature. In addition, preliminary experiments examining the visitor-produced disturbances on δ(13)CCO2 were conducted during the various cave ventilation stages to explore the potential use of this parameter as an indicator of anthropic pressure in caves. Our data show that visits (overall stay of 60-85 min; i.e., 4 people for 20 min) significantly affected δ(13)CCO2 (up to Δδ(13)C ∼ -2‰) in the Polychrome Hall of Altamira Cave under conditions of low natural CO2 (discharge stage), whereas it remained almost unaltered under circumstances of high CO2 concentration (recharge stage). This demonstrates that δ(13)CCO2 is sensitive to perturbations

  4. Distribution and Potential Indicators of Hospitalized Cases of Neurocysticercosis and Epilepsy in Ecuador from 1996 to 2008

    Science.gov (United States)

    Gabriël, Sarah; Benitez-Ortiz, Washington; Saegerman, Claude; Dorny, Pierre; Berkvens, Dirk; Abatih, Emmanuel Nji

    2015-01-01

    Background Epilepsy is one of the most common signs of Neurocysticercosis (NCC). In this study, spatial and temporal variations in the incidence of hospitalized cases (IHC) of epilepsy and NCC in Ecuadorian municipalities were analyzed. Additionally, potential socio-economic and landscape indicators were evaluated in order to understand in part the macro-epidemiology of the Taenia solium taeniasis/cysticercosis complex. Methodology Data on the number of hospitalized epilepsy and NCC cases by municipality of residence were obtained from morbidity-hospital systems in Ecuador. SatScan software was used to determine whether variations in the IHC of epilepsy and NCC in space and time. In addition, several socio-economic and landscape variables at municipality level were used to study factors intervening in the macro-epidemiology of these diseases. Negative Binomial regression models through stepwise selection and Bayesian Model Averaging (BMA) were used to explain the variations in the IHC of epilepsy and NCC. Principal findings Different clusters were identified through space and time. Traditional endemic zones for NCC and epilepsy, recognized in other studies were confirmed in our study. However, for both disorders more recent clusters were identified. Among municipalities, an increasing tendency for IHC of epilepsy, and a decreasing tendency for the IHC of NCC were observed over time. In contrast, within municipalities a positive linear relationship between both disorders was found. An increase in the implementation of systems for eliminating excrements would help to reduce the IHC of epilepsy by 1.00% (IC95%; 0.2%–1.8%) and by 5.12% (IC95%; 3.63%-6.59%) for the IHC of NCC. The presence of pig production was related to IHC of NCC. Conclusion/Significance Both disorders were related to the lack of an efficient system for eliminating excrements. Given the appearance of recent epilepsy clusters, these locations should be studied in depth to discriminate epilepsies due

  5. Distribution and Potential Indicators of Hospitalized Cases of Neurocysticercosis and Epilepsy in Ecuador from 1996 to 2008.

    Directory of Open Access Journals (Sweden)

    Lenin Ron-Garrido

    2015-11-01

    Full Text Available Epilepsy is one of the most common signs of Neurocysticercosis (NCC. In this study, spatial and temporal variations in the incidence of hospitalized cases (IHC of epilepsy and NCC in Ecuadorian municipalities were analyzed. Additionally, potential socio-economic and landscape indicators were evaluated in order to understand in part the macro-epidemiology of the Taenia solium taeniasis/cysticercosis complex.Data on the number of hospitalized epilepsy and NCC cases by municipality of residence were obtained from morbidity-hospital systems in Ecuador. SatScan software was used to determine whether variations in the IHC of epilepsy and NCC in space and time. In addition, several socio-economic and landscape variables at municipality level were used to study factors intervening in the macro-epidemiology of these diseases. Negative Binomial regression models through stepwise selection and Bayesian Model Averaging (BMA were used to explain the variations in the IHC of epilepsy and NCC.Different clusters were identified through space and time. Traditional endemic zones for NCC and epilepsy, recognized in other studies were confirmed in our study. However, for both disorders more recent clusters were identified. Among municipalities, an increasing tendency for IHC of epilepsy, and a decreasing tendency for the IHC of NCC were observed over time. In contrast, within municipalities a positive linear relationship between both disorders was found. An increase in the implementation of systems for eliminating excrements would help to reduce the IHC of epilepsy by 1.00% (IC95%; 0.2%-1.8% and by 5.12% (IC95%; 3.63%-6.59% for the IHC of NCC. The presence of pig production was related to IHC of NCC.Both disorders were related to the lack of an efficient system for eliminating excrements. Given the appearance of recent epilepsy clusters, these locations should be studied in depth to discriminate epilepsies due to NCC from epilepsies due to other causes. Field

  6. Spatiotemporal distribution of δ(13)CCO2 in a shallow cave and its potential use as indicator of anthropic pressure.

    Science.gov (United States)

    Gázquez, Fernando; Quindós-Poncela, Luis; Sainz-Fernández, Carlos; Fernández-Villar, Alicia; Fuente-Merino, Ismael; Celaya-Gonzalez, Santiago

    2016-09-15

    This study deals with the spatiotemporal dynamics of CO2 and its isotopic composition (δ(13)CCO2) in the atmosphere of Altamira Cave (northern Spain) over two annual cycles. In general terms, the cavity shows two distinct ventilation modes, acting as a CO2 reservoir from October to May (recharge stage), while actively exchanging gases with the outside atmosphere between July and September (discharge stage). In recharge mode, the in-cave air shows higher and relatively homogeneous CO2 values (3332 ± 521 ppm) with lower δ(13)CCO2 (-23.2 ± 0.4‰). In contrast, during the discharge stage, the CO2 concentrations are lower and relatively more variable (1383 ± 435 ppm) and accompanied by higher δ(13)CCO2 (up to -12‰). This seasonal pattern is controlled by the distinct rates of exchange of air masses with the external atmosphere through the annual cycle, as well as by changes in the production of CO2 in the soil and natural fluctuations in the concentration of dissolved inorganic carbon transported by drip water into the cave. In contrast to the interpretations of previous studies in Altamira Cave, no local air intakes into the deepest cave sections were flagged by our δ(13)C measurements. This finding is also supported by analyses of CO2 and (222)Rn in air, density of airborne particles and air temperature. In addition, preliminary experiments examining the visitor-produced disturbances on δ(13)CCO2 were conducted during the various cave ventilation stages to explore the potential use of this parameter as an indicator of anthropic pressure in caves. Our data show that visits (overall stay of 60-85 min; i.e., 4 people for 20 min) significantly affected δ(13)CCO2 (up to Δδ(13)C ∼ -2‰) in the Polychrome Hall of Altamira Cave under conditions of low natural CO2 (discharge stage), whereas it remained almost unaltered under circumstances of high CO2 concentration (recharge stage). This demonstrates that δ(13)CCO2 is sensitive to perturbations

  7. Late-onset intermittent fasting dietary restriction as a potential intervention to retard age-associated brain function impairments in male rats

    OpenAIRE

    Singh, Rumani; Lakhanpal, Dinesh; Kumar, Sushil; Sharma, Sandeep; Kataria, Hardeep; Kaur, Manpreet; Kaur, Gurcharan

    2011-01-01

    Lifelong dietary restriction (DR) is known to have many potential beneficial effects on brain function as well as delaying the onset of neurological diseases. In the present investigation, the effect of late-onset short-term intermittent fasting dietary restriction (IF-DR) regimen was studied on motor coordination and cognitive ability of ageing male rats. These animals were further used to estimate protein carbonyl content and mitochondrial complex I–IV activity in different regions of brain...

  8. Analysis on the training effect of criteria and practical guidance for determination of brain death: evoked potentials

    Directory of Open Access Journals (Sweden)

    Yan ZHANG

    2015-12-01

    Full Text Available Objective To analyze the training results of short-latency somatosensory-evoked potential (SLSEP for brain death determination and to improve the training program. Methods A total of 101 trainees received theoretical training, simulation skills training, bedside skills training and test analysis for SLSEP in brain death determination. The composition of trainees was analyzed and the error rates of 6 knowledge points were calculated. Univariate and multivariate backward Logistic regression analyses were used to analyze the influence of factors including sex, age, specialty, professional category, professional qualification and hospital level, on the error rates. Results Among them, trainees of 30-49 years old occupied 76.24% (77/101, most of them were from third grade, grade A hospitals (98.02%, 99/101, and 78 trainees (77.23% were from Department of Neurology. There were 82 clinicians (81.19%, 31 (30.69% had senior certificate and 42 (41.58% had intermediate certificate. Total error rate of 6 knowledge points was 4.50% (91/2020. Of the 6 knowledge points, the error rate of pitfalls was the highest (9.41%, 19/202, followed by result determination (5.94% , 12/202, recording techniques (4.75% , 24/505, procedures (3.96%, 32/808, sequence of confirmatory tests (1.98%, 2/101 and environmental conditions (0.99%, 2/202. Univariate and multivariate Logistic regression analyses showed that age (OR = 1.566, 95% CI: 1.116-2.197; P = 0.009 and professional qualification (OR = 1.669, 95% CI: 1.163-2.397; P = 0.005 were independent risk factors associated with high error rates. Conclusions The differences between brain death determination and routine check of SLSEP should be paid more attention to improve the quality of determination for brain death by SLSEP.  DOI: 10.3969/j.issn.1672-6731.2015.12.007

  9. Development of Blood-Brain Barrier Permeable Nitrocatechol-Based Catechol O-Methyltransferase Inhibitors with Reduced Potential for Hepatotoxicity.

    Science.gov (United States)

    Silva, Tiago; Mohamed, Tarek; Shakeri, Arash; Rao, Praveen P N; Martínez-González, Loreto; Pérez, Daniel I; Martínez, Ana; Valente, Maria João; Garrido, Jorge; Uriarte, Eugenio; Serrão, Paula; Soares-da-Silva, Patrício; Remião, Fernando; Borges, Fernanda

    2016-08-25

    Recent efforts have been focused on the development of centrally active COMT inhibitors, which can be valuable assets for neurological disorders such as Parkinson's disease, due to the severe hepatotoxicity risk associated with tolcapone. New nitrocatechol COMT inhibitors based on naturally occurring caffeic acid and caffeic acid phenethyl ester were developed. All nitrocatechol derivatives displayed potent inhibition of peripheral and cerebral COMT within the nanomolar range. Druglike derivatives 13, 15, and 16 were predicted to cross the blood-brain barrier in vitro and were significantly less toxic than tolcapone and entacapone when incubated at 50 μM with rat primary hepatocytes. Moreover, their unique acidity and electrochemical properties decreased the chances of formation of reactive quinone-imines and, as such, the potential for hepatotoxicity. The binding mode of 16 confirmed that the major interactions with COMT were established via the nitrocatechol ring, allowing derivatization of the side chain for future lead optimization efforts.

  10. Expression of physiological sensation of anatomical patterns in wood: An event-related brain potential study

    OpenAIRE

    Sha Sha Song; Guang Jie Zhao

    2012-01-01

    The emotional and psychological activities associated with the visual perception of macroscopic and microscopic structure patterns of wood were investigated. The macroscopic and microscopic structure patterns of 18 different timber tree species of northeast China were selected as the research objects, and these were divided into eight categories for event-related potential analysis. The 30 effective subjects’ tasks were to watch the wood structure stimuli patterns and evaluate them on a 7-poi...

  11. Exercise offers anxiolytic potential: A role for stress and brain noradrenergic-galaninergic mechanisms

    OpenAIRE

    Sciolino, Natale R.; Holmes, Philip V.

    2012-01-01

    Although physical activity reduces anxiety in humans, the neural basis for this response is unclear. Rodent models are essential to understand the mechanisms that underlie the benefits of exercise. However, it is controversial whether exercise exerts anxiolytic-like potential in rodents. Evidence is reviewed to evaluate the effects of wheel running, an experimental mode of exercise in rodents, on behavior in tests of anxiety and on norepinephrine and galanin systems in neural circuits that re...

  12. Persistence of somatic and F-specific coliphages, potential indicators of fecal contamination, on spinach foliar tissue

    Science.gov (United States)

    Recent outbreaks of foodborne illness have been linked to consumption of fresh leafy greens. E. coli is commonly used as the indicator microorganism for fecal contamination on leafy greens. However, alternative microorganisms, such as coliphages, may deserve consideration as indicators of fecal cont...

  13. From the heart to the brain: a study of heartbeat contingent scalp potentials.

    Science.gov (United States)

    Schandry, R; Sparrer, B; Weitkunat, R

    1986-11-01

    Heartbeat perception has become the most widely studied example of visceral perception. In the present study scalp potentials contingent to the visceral event "heartbeat" were investigated. Scalp potentials, averaged time-locked to the EKG-R-wave, were studied at Fz, Cz, and Pz under four conditions: resting (baseline), heartbeat discrimination task, signal detection task, and heartbeat discrimination task after physical exercise. 22 subjects were assigned to the two groups "good" and "poor" perceivers, according to their performance in an initial heartbeat perception test. Event related potentials (ERPs) of "good" perceivers were more stable across conditions than those of "poor" perceivers. Peak latency within the range of 200 to 300 ms differed significantly between conditions. A principal component analysis performed on the ERP averages extracted five components. Subsequent ANOVAs across factor scores yielded significant main effects for the "groups" factor, experimental conditions and electrode sites. The strongest effects occurred over the frontal region in the latency range of 250-400 ms (following the EKG-R-wave). These were found to be not due to artifactual EKG influences. PMID:3793380

  14. Urban liveability: emerging lessons from Australia for exploring the potential for indicators to measure the social determinants of health.

    Science.gov (United States)

    Badland, Hannah; Whitzman, Carolyn; Lowe, Melanie; Davern, Melanie; Aye, Lu; Butterworth, Iain; Hes, Dominique; Giles-Corti, Billie

    2014-06-01

    It has long been recognised that urban form impacts on health outcomes and their determinants. There is growing interest in creating indicators of liveability to measure progress towards achieving a wide range of policy outcomes, including enhanced health and wellbeing, and reduced inequalities. This review aimed to: 1) bring together the concepts of urban 'liveability' and social determinants of health; 2) synthesise the various liveability indicators developed to date; and 3) assess their quality using a health and wellbeing lens. Between 2011 and 2013, the research team reviewed 114 international academic and policy documents, as well as reports related to urban liveability. Overall, 233 indicators were found. Of these, 61 indicators were regarded as promising, 57 indicators needed further development, and 115 indicators were not useful for our purposes. Eleven domains of liveability were identified that likely contribute to health and wellbeing through the social determinants of health. These were: crime and safety; education; employment and income; health and social services; housing; leisure and culture; local food and other goods; natural environment; public open space; transport; and social cohesion and local democracy. Many of the indicators came from Australian sources; however most remain relevant from a 'global north' perspective. Although many indicators were identified, there was inconsistency in how these domains were measured. Few have been validated to assess their association with health and wellbeing outcomes, and little information was provided for how they should be applied to guide urban policy and practice. There is a substantial opportunity to further develop these measures to create a series of robust and evidence-based liveability indices, which could be linked with existing health and wellbeing data to better inform urban planning policies within Australia and beyond. PMID:24762261

  15. Pre-Activation Negativity (PrAN) in Brain Potentials to Unfolding Words

    Science.gov (United States)

    Söderström, Pelle; Horne, Merle; Frid, Johan; Roll, Mikael

    2016-01-01

    We describe an event-related potential (ERP) effect termed the “pre-activation negativity” (PrAN), which is proposed to index the degree of pre-activation of upcoming word-internal morphemes in speech processing. Using lexical competition measures based on word-initial speech fragments (WIFs), as well as statistical analyses of ERP data from three experiments, it is shown that the PrAN is sensitive to lexical competition and that it reflects the degree of predictive certainty: the negativity is larger when there are fewer upcoming lexical competitors. PMID:27777558

  16. Pain indicators in newborns

    Directory of Open Access Journals (Sweden)

    Spasojević Slobodan

    2008-01-01

    Full Text Available Definition of pain. The International Association for the Study of Pain has defined pain as "an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage." The interpretation of pain is subjective. Each person forms an internal construct of pain through encountered injury. Pain and newborn. The issue of pain perception in newborns, its management and prevention has been neglected for decades. The inability of "self-report" of painful experience has contributed significantly to misunderstanding of the importance of this problem and in­adequate treatment. The main characteristic of this 'critical window of brain development' period is rapid enlargement of brain volume and its great plasticity. Harmful short-term and long-term consequences can arise as a consequence of disturbance of the sophisticated balance between newborn and its surrounding. Neonatal pain indicators. As a response to a present painful stimulus, the newborn adapts to this acute stress with changes in endocrine, vegetative, immune and behavioral area. An ideal pain indicator in neonatal period does not exist. There are several different groups o them, namely contextual and developmental indicators (gestational age, contributed illness, medication, for example, physiological (heart rate, vagal tone, breathing rate, blood pressure, oxygen saturation, transcutaneous partial pressures of oxygen and carbon-dioxide, intracranial pressure, palm sweating and behavioral ones (face expression, movements of limbs, cry, several neonatal pain scales were constructed on the basis of these indicators. .

  17. Event-related brain potential evidence for animacy processing asymmetries during sentence comprehension.

    Science.gov (United States)

    Nieuwland, Mante S; Martin, Andrea E; Carreiras, Manuel

    2013-08-01

    The animacy distinction is deeply rooted in the language faculty. A key example is differential object marking, the phenomenon where animate sentential objects receive specific marking. We used event-related potentials to examine the neural processing consequences of case-marking violations on animate and inanimate direct objects in Spanish. Inanimate objects with incorrect prepositional case marker 'a' ('al suelo') elicited a P600 effect compared to unmarked objects, consistent with previous literature. However, animate objects without the required prepositional case marker ('el obispo') only elicited an N400 effect compared to marked objects. This novel finding, an exclusive N400 modulation by a straightforward grammatical rule violation, does not follow from extant neurocognitive models of sentence processing, and mirrors unexpected "semantic P600" effects for thematically problematic sentences. These results may reflect animacy asymmetry in competition for argument prominence: following the article, thematic interpretation difficulties are elicited only by unexpectedly animate objects.

  18. Preserving Brain Function in Aging: The Anti-glycative Potential of Berry Fruit.

    Science.gov (United States)

    Thangthaeng, Nopporn; Poulose, Shibu M; Miller, Marshall G; Shukitt-Hale, Barbara

    2016-09-01

    Advanced glycation end products (AGEs) are naturally occurring macromolecules that are formed in vivo by the non-enzymatic modification of proteins, lipids, or nucleic acids by sugar, even in the absence of hyperglycemia. In the diet, AGEs are found in animal products, and additional AGEs are produced when those foods are cooked at high temperatures. Studies have linked AGEs to various age-related physiological changes, including wrinkles, diabetic complications, and neurodegenerative disease, including Alzheimer's disease. Dietary berry fruits have been shown to reduce the severity or slow the progression of many physiological changes and disease pathologies that accompany aging. Emerging evidence has shown that the phytochemicals found in berry fruits exhibit anti-glycative activity. In this review, we briefly summarize the current evidence supporting the neuroprotective anti-glycative activity of berry fruits and their potential to preserve cognitive function during aging. PMID:27166828

  19. Feasibility of using the computed tomography dose indices to estimate radiation dose to partially and fully irradiated brains in pediatric neuroradiology examinations

    International Nuclear Information System (INIS)

    The purpose of this study was two-fold: (a) to measure the dose to the brain using clinical protocols at our institution, and (b) to develop a scanner-independent dosimetry method to estimate brain dose. Radiation dose was measured with a pediatric anthropomorphic phantom and MOSFET detectors. Six current neuroradiology protocols were used: brain, sinuses, facial bones, orbits, temporal bones, and craniofacial areas. Two different CT vendor scanners (scanner A and B) were used. Partial volume correction factors (PVCFs) were determined for the brain to account for differences between point doses measured by the MOSFETs and average organ dose. The CTDIvol and DLP for each protocol were recorded. The dose to the brain (mGy) for scanners A and B was 10.7 and 10.0 for the brain protocol, 7.8 and 3.2 for the sinus, 10.2 and 8.6 for the facial bones, 7.4 and 4.7 for the orbits and 1.6 and 1.9 for the temporal bones, respectively. On scanner A, the craniofacial protocol included a standard and high dose option; the dose measured for these exams was 3.9 and 16.9 mGy, respectively. There was only one craniofacial protocol on scanner B; the brain dose measured on this exam was 4.8 mGy. A linear correlation was found between DLP and brain dose with the conversion factors: 0.049 (R2 = 0.87), 0.046 (R2 = 0.89) for scanner A and B, and 0.048 (R2 = 0.89) for both scanners. The range of dose observed was between 1.8 and 16.9 mGy per scan. This suggests that brain dose estimates may be made from DLP. (paper)

  20. Lightning potential forecast over Nanjing with denoised sounding-derived indices based on SSA and CS-BP neural network

    Science.gov (United States)

    Wang, Jun; Sheng, Zheng; Zhou, Bihua; Zhou, Shudao

    2014-02-01

    The method of using the back propagation neural network improved by cuckoo search algorithm (hereafter CS-BP neural network) to forecast lightning occurrence from sounding-derived indices over Nanjing is presented. The general distribution features of lightning activities over Nanjing area are summarized and analyzed first. The sounding data of 156 thunderstorm days and 164 fair-weather days during the years 2007-2012 are used to calculate the values of sounding-derived indices. The indices are pre-filtered using singular spectrum analysis (hereafter SSA) as preprocessing technique and 4 most pertinent indices (namely CAPE, K, JI and SWEAT) are determined as inputs of CS-BP network by a linear bivariate analysis and selection algorithm. The cases of 2007-2010 are used to train CS-BP network and the cases of 2011-2012 are used as an independent sample to test the forecast performance. Some statistical skill score parameters (namely POD, SAR, CSI, et.al.) indicate that the CS-BP model excels in lightning forecasting and has a better performance compared with the traditional BP neural network and linear multiregression method.

  1. Auditory event-related potentials as indicators of good prognosis in coma of non-anoxic etiology

    OpenAIRE

    Jabbour, Rosette; Sawaya, Raja A.

    2010-01-01

    The aim of this study is to evaluate whether auditory event-related potentials can predict the prognosis of recovery from coma resulting from different etiologies. The results of this study could then be used as an adjuvant test in helping the clinician evaluate patients in coma. We performed P300 auditory event-related potentials on 21 patients who developed a state of coma at our institution. We compared the results to the Glasgow coma scale at the onset of coma, on day 3, and day 21. We...

  2. Comparison of brain mechanisms underlying the processing of Chinese characters and pseudo-characters: an event-related potential study.

    Science.gov (United States)

    Wang, Ting; Li, Hong; Zhang, Qinglin; Tu, Shen; Yu, Caiyun; Qiu, Jiang

    2010-04-01

    Most Chinese characters are composed of a semantic radical on the left and a phonetic radical on the right. The semantic radical provides the semantic information; the phonetic radical provides information concerning the pronunciation of the whole character. The pseudo-characters in the study consisted of different sub-lexical parts of real Chinese characters and consequently they also had the semantic radical and the phonetic radical. But they were not readable and had no actual meaning. In order to investigate the spatiotemporal cortical activation patterns underlying the orthographic, phonological and semantic processing of Chinese characters, we used event-related brain potentials (ERPs) to explore the processing of Chinese characters and pseudo-characters when 14 healthy Chinese college students viewed the characters passively. Results showed that both Chinese characters and pseudo-characters elicited an evident negative potential peaking around 120 ms (N120), which appeared to reflect initial orthographic distinction and evaluation. Then, Chinese pseudo-characters elicited a more positive ERP deflection (P220) than did Chinese characters 200-250 ms after onset of the stimuli. It was similar to the recognition potential (RP) and might reflect the integration processes of phonological and semantic processing on the basis of early orthographic information. Dipole source analysis of the difference wave (pseudo-characters minus characters) indicated that a generator localized in the left temporal-occipital junction contributed to this effect, which was possibly related to phonological and perceptual-semantic information integration. Between 350-450 ms, a greater negativity (N360) in pseudo-characters as compared to characters was found over midline fronto-central scalp regions. Dipole analysis localized the generator of N360 in the right parahippocampal cortex. Therefore, the N360 might be an N400 component and reflect the higher-level semantic activation on the

  3. Accurate Computation of Reduction Potentials of 4Fe−4S Clusters Indicates a Carboxylate Shift in Pyrococcus furiosus Ferredoxin

    DEFF Research Database (Denmark)

    Kepp, Kasper Planeta; Ooi, Bee Lean; Christensen, Hans Erik Mølager

    2007-01-01

    This work describes the computation and accurate reproduction of subtle shifts in reduction potentials for two mutants of the iron-sulfur protein Pyrococcus furiosus ferredoxin. The computational models involved only first-sphere ligands and differed with respect to one ligand, either acetate (as...

  4. Brain potentials reflect access to visual and emotional memories for faces.

    Science.gov (United States)

    Bobes, Maria A; Quiñonez, Ileana; Perez, Jhoanna; Leon, Inmaculada; Valdés-Sosa, Mitchell

    2007-05-01

    Familiar faces convey different types of information, unlocking memories related to social-emotional significance. Here, the availability over time of different types of memory was evaluated using the time-course of P3 event related potentials. Two oddball paradigms were employed, both using unfamiliar faces as standards. The infrequent targets were, respectively, artificially-learned faces (devoid of social-emotional content) and faces of acquaintances. Although in both tasks targets were detected accurately, the corresponding time-course and scalp distribution of the P3 responses differed. Artificially-learned and acquaintance faces both elicited a P3b, maximal over centro-parietal sites, and a latency of 500ms. Faces of acquaintances elicited an additional component, an early P3 maximal over frontal sites: with a latency of 350ms. This suggests that visual familiarity can only trigger the overt recognition processes leading to the slower P3b, whereas emotional-social information can also elicit fast and automatic assessments (indexed by the frontal-P3) crucial for successful social interactions.

  5. Exploring the effects of antisocial personality traits on brain potentials during face processing.

    Directory of Open Access Journals (Sweden)

    Daniela M Pfabigan

    Full Text Available Antisocial individuals are characterized to display self-determined and inconsiderate behavior during social interaction. Furthermore, recognition deficits regarding fearful facial expressions have been observed in antisocial populations. These observations give rise to the question whether or not antisocial behavioral tendencies are associated with deficits in basic processing of social cues. The present study investigated early visual stimulus processing of social stimuli in a group of healthy female individuals with antisocial behavioral tendencies compared to individuals without these tendencies while measuring event-related potentials (P1, N170. To this end, happy and angry faces served as feedback stimuli which were embedded in a gambling task. Results showed processing differences as early as 88-120 ms after feedback onset. Participants low on antisocial traits displayed larger P1 amplitudes than participants high on antisocial traits. No group differences emerged for N170 amplitudes. Attention allocation processes, individual arousal levels as well as face processing are discussed as possible causes of the observed group differences in P1 amplitudes. In summary, the current data suggest that sensory processing of facial stimuli is functionally intact but less ready to respond in healthy individuals with antisocial tendencies.

  6. Iodine-123 labeled derivatives of methylphenidate: potential SPECT radiopharmaceuticals for brain dopamine transporters

    International Nuclear Information System (INIS)

    Since dl-threo-[11C]methylphenidate (Ritalin) and especially the more active enantiomer, d-threo-[11C]methylphenidate, have favorable properties for PET studies, we prepared two radioiodinated analogs of methylphenidate, p-[123I]iodomethylphenidate and m-[123I]iodo-p-hydroxymethylphenidate with a view to evaluating them as potential SPECT tracers. To prepare p-[123I]iodomethylphenidate, the p-tributyltin derivative was prepared from the previously reported p-bromomethylphenidate and reacted under acidic conditions with I-123 iodide plus chloramine-T at room temperature for 90 seconds. The predomimant radioactive product was obtained in 85% radiochemical yield and > 10 Ci/μmol specific radioactivity after HPLC purification. It had the same HPLC retention time as a spectroscopically characterized non-radioactive p-iodomethylphenidate standard prepared via nitration of methylphenidate and diazotization, after protection of the secondary amino group by benzoylation. A second radioiodinated methylphenidate derivative, m-[123)I]iodop-hydroxymethylphenidate was prepared in 80% radiochemical yield by direct iodination of the known p-hydroxymethylphenidate. In this case the non-radioactive standard was prepared by iodination of p-hydroxyritalinic acid using I2 and iodic acid, followed by esterification. (author)

  7. Therapeutic potential of targeting hydrogen peroxide metabolism in the treatment of brain ischaemia.

    Science.gov (United States)

    Armogida, Marta; Nisticò, Robert; Mercuri, Nicola Biagio

    2012-06-01

    For many years after its discovery, hydrogen peroxide (H₂O₂) was viewed as a toxic molecule to human tissues; however, in light of recent findings, it is being recognized as an ubiquitous endogenous molecule of life as its biological role has been better elucidated. Indeed, increasing evidence suggests that H₂O₂ may act as a second messenger with a pro-survival role in several physiological processes. In addition, our group has recently demonstrated neuroprotective effects of H₂O₂ on in vitro and in vivo ischaemic models through a catalase (CAT) enzyme-mediated mechanism. Therefore, the present review summarizes experimental data supporting a neuroprotective potential of H₂O₂ in ischaemic stroke that has been principally achieved by means of pharmacological and genetic strategies that modify either the activity or the expression of the superoxide dismutase (SOD), glutathione peroxidase (GPx) and CAT enzymes, which are key regulators of H₂O₂ metabolism. It also critically discusses a translational impact concerning the role played by H₂O₂ in ischaemic stroke. Based on these data, we hope that further research will be done in order to better understand the mechanisms underlying H₂O₂ functions and to promote successful H₂O₂ signalling based therapy in ischaemic stroke.

  8. Iodine-123 labeled derivatives of methylphenidate: potential SPECT radiopharmaceuticals for brain dopamine transporters

    Energy Technology Data Exchange (ETDEWEB)

    Pan, D.; Gatley, S.J.; Chen, R.; Ding, Y.-S. [Brookhaven National Lab., Upton, NY (United States)

    1996-06-01

    Since dl-threo-[{sup 11}C]methylphenidate (Ritalin) and especially the more active enantiomer, d-threo-[{sup 11}C]methylphenidate, have favorable properties for PET studies, we prepared two radioiodinated analogs of methylphenidate, p-[{sup 123}I]iodomethylphenidate and m-[{sup 123}I]iodo-p-hydroxymethylphenidate with a view to evaluating them as potential SPECT tracers. To prepare p-[{sup 123}I]iodomethylphenidate, the p-tributyltin derivative was prepared from the previously reported p-bromomethylphenidate and reacted under acidic conditions with I-123 iodide plus chloramine-T at room temperature for 90 seconds. The predomimant radioactive product was obtained in 85% radiochemical yield and > 10 Ci/{mu}mol specific radioactivity after HPLC purification. It had the same HPLC retention time as a spectroscopically characterized non-radioactive p-iodomethylphenidate standard prepared via nitration of methylphenidate and diazotization, after protection of the secondary amino group by benzoylation. A second radioiodinated methylphenidate derivative, m-[{sup 123}I]iodop-hydroxymethylphenidate was prepared in 80% radiochemical yield by direct iodination of the known p-hydroxymethylphenidate. In this case the non-radioactive standard was prepared by iodination of p-hydroxyritalinic acid using I{sub 2} and iodic acid, followed by esterification. (author).

  9. The Impact of Task Demands on Fixation-Related Brain Potentials during Guided Search

    Science.gov (United States)

    Ahrens, Barry; Connolly, Patrick

    2016-01-01

    Recording synchronous data from EEG and eye-tracking provides a unique methodological approach for measuring the sensory and cognitive processes of overt visual search. Using this approach we obtained fixation related potentials (FRPs) during a guided visual search task specifically focusing on the lambda and P3 components. An outstanding question is whether the lambda and P3 FRP components are influenced by concurrent task demands. We addressed this question by obtaining simultaneous eye-movement and electroencephalographic (EEG) measures during a guided visual search task while parametrically modulating working memory load using an auditory N-back task. Participants performed the guided search task alone, while ignoring binaurally presented digits, or while using the auditory information in a 0, 1, or 2-back task. The results showed increased reaction time and decreased accuracy in both the visual search and N-back tasks as a function of auditory load. Moreover, high auditory task demands increased the P3 but not the lambda latency while the amplitude of both lambda and P3 was reduced during high auditory task demands. The results show that both early and late stages of visual processing indexed by FRPs are significantly affected by concurrent task demands imposed by auditory working memory. PMID:27286248

  10. Transcriptomic gene-network analysis of exposure to silver nanoparticle reveals potentially neurodegenerative progression in mouse brain neural cells.

    Science.gov (United States)

    Lin, Ho-Chen; Huang, Chin-Lin; Huang, Yuh-Jeen; Hsiao, I-Lun; Yang, Chung-Wei; Chuang, Chun-Yu

    2016-08-01

    Silver nanoparticles (AgNPs) are commonly used in daily living products. AgNPs can induce inflammatory response in neuronal cells, and potentially develop neurological disorders. The gene networks in response to AgNPs-induced neurodegenerative progression have not been clarified in various brain neural cells. This study found that 3-5nm AgNPs were detectable to enter the nuclei of mouse neuronal cells after 24-h of exposure. The differentially expressed genes in mouse brain neural cells exposure to AgNPs were further identified using Phalanx Mouse OneArray® chip, and permitted to explore the gene network pathway regulating in neurodegenerative progression according to Cytoscape analysis. In focal adhesion pathway of ALT astrocytes, AgNPs induced the gene expression of RasGRF1 and reduced its downstream BCL2 gene for apoptosis. In cytosolic DNA sensing pathway of microglial BV2 cells, AgNPs reduced the gene expression of TREX1 and decreased IRF7 to release pro-inflammatory cytokines for inflammation and cellular activation. In MAPK pathway of neuronal N2a cells, AgNPs elevated GADD45α gene expression, and attenuated its downstream PTPRR gene to interfere with neuron growth and differentiation. Moreover, AgNPs induced beta amyloid deposition in N2a cells, and decreased PSEN1 and PSEN2, which may disrupt calcium homeostasis and presynaptic dysfunction for Alzheimer's disease development. These findings suggested that AgNPs exposure reveals the potency to induce the progression of neurodegenerative disorder. PMID:27131904

  11. Single trial predictors for gating motor-imagery brain-computer interfaces based on sensorimotor rhythm and visual evoked potentials

    Directory of Open Access Journals (Sweden)

    Andrew eGeronimo

    2016-04-01

    Full Text Available For brain-computer interfaces (BCIs that utilize visual cues to direct the user, the neural signals extracted by the computer are representative of ongoing processes, visual evoked responses, and voluntary modulation. We proposed to use three brain signatures for predicting success on a single trial of a BCI task. The first two features, the amplitude and phase of the pre-trial mu amplitude, were chosen as a correlate for cortical excitability. The remaining feature, related to the visually evoked response to the cue, served as a possible measure of fixation and attention to the task. Of these three features, mu rhythm amplitude over the central electrodes at the time of cue presentation and to a lesser extent the single trial visual evoked response were correlated with the success on the subsequent imagery task. Despite the potential for gating trials using these features, an offline gating simulation was limited in its ability to produce an increase in device throughput. This discrepancy highlights a distinction between the identification of predictive features, and the use of this knowledge in an online BCI. Using such a system, we cannot assume that the user will respond similarly when faced with a scenario where feedback is altered by trials that are gated on a regular basis. The results of this study suggest the possibility of using individualized, pre-task neural signatures for personalized and asynchronous (self-paced BCI applications, although these effects need to be quantified in a real-time adaptive scenario in a future study.

  12. Mir-34a mimics are potential therapeutic agents for p53-mutated and chemo-resistant brain tumour cells.

    Directory of Open Access Journals (Sweden)

    Yuen Ngan Fan

    Full Text Available Chemotherapeutic drug resistance and relapse remains a major challenge for paediatric (medulloblastoma and adult (glioblastoma brain tumour treatment. Medulloblastoma tumours and cell lines with mutations in the p53 signalling pathway have been shown to be specifically insensitive to DNA damaging agents. The aim of this study was to investigate the potential of triggering cell death in p53 mutated medulloblastoma cells by a direct activation of pro-death signalling downstream of p53 activation. Since non-coding microRNAs (miRNAs have the ability to fine tune the expression of a variety of target genes, orchestrating multiple downstream effects, we hypothesised that triggering the expression of a p53 target miRNA could induce cell death in chemo-resistant cells. Treatment with etoposide, increased miR-34a levels in a p53-dependent fashion and the level of miR-34a transcription was correlated with the cell sensitivity to etoposide. miR-34a activity was validated by measuring the expression levels of one of its well described target: the NADH dependent sirtuin1 (SIRT1. Whilst drugs directly targeting SIRT1, were potent to trigger cell death at high concentrations only, introduction of synthetic miR-34a mimics was able to induce cell death in p53 mutated medulloblastoma and glioblastoma cell lines. Our results show that the need of a functional p53 signaling pathway can be bypassed by direct activation of miR-34a in brain tumour cells.

  13. Neural Consequences of Increasing Body Weight: Evidence from Somatosensory Evoked Potentials and the Frequency-Specificity of Brain Oscillations

    Science.gov (United States)

    Lhomond, Olivia; Teasdale, Normand; Simoneau, Martin; Mouchnino, Laurence

    2016-01-01

    Previous studies on the control of human balance suggested that increased pressure under the feet, leading to reduced plantar sole mechanoreceptors sensitivity, increases body sway. Although this suggestion is attracting, it is unclear whether increased plantar sole pressure simply reduces the transmission of plantar sole afferent to the cortex or also alters the sensorimotor integrative mechanisms. Here we used electrical stimulation applied under the sole of the foot to probe the sensorimotor mechanisms processing foot mechanoreceptors. Balance control of healthy individuals was assessed either when wearing a loaded vest or in normal-weight condition. In the Loaded condition, we observed decreased cortical activity over the primary somatosensory cortex (SI) for both an early P50-N90 somatosensory evoked potential (SEP) and for oscillatory brain activity within the gamma band (30–80 Hz). These reductions were interpreted as a disrupted early sensory transmission (i.e., decreased early SEP) leading to a decreased perception of plantar sole sensory information (i.e., decreased gamma band power). These early sensory mechanisms for the Loaded condition were associated with an increase in the late P170-N210 SEP and oscillatory brain activity within the beta band (19–24 Hz). These neural signatures involved areas which are engaged in sensorimotor integrative processes (secondary somatosensory cortex (SII) and right temporoparietal junction). Altered early and late sensory processes may result from the increase pressure on the mechanoreceptors of the foot sole and not from postural instability per se. Indeed, postural instability with normal weight condition did not lead to SEP changes. PMID:27445758

  14. Potential fluid biomarkers for pathological brain changes in Alzheimer's disease: Implication for the screening of cognitive frailty

    Science.gov (United States)

    Ruan, Qingwei; D'Onofrio, Grazia; Sancarlo, Daniele; Greco, Antonio; Yu, Zhuowei

    2016-01-01

    Cognitive frailty (CF) overlaps with early neuropathological alterations associated with aging-related major neurocognitive disorders, including Alzheimer's disease (AD). Fluid biomarkers for these pathological brain alterations allow for early diagnosis in the preclinical stages of AD, and for objective prognostic assessments in clinical intervention trials. These biomarkers may also be helpful in the screening of CF. The present study reviewed the literature and identified systematic reviews of cohort studies and other authoritative reports. The selection criteria for potentially suitable fluid biomarkers included: i) Frequent use in studies of fluid-derived markers and ii) evidence of novel measurement techniques for fluid-derived markers. The present study focused on studies that assessed these biomarkers in AD, mild cognitive impairment and non-AD demented subjects. At present, widely used fluid biomarkers include cerebrospinal fluid (CSF), total tau, phosphorylated tau and amyloid-β levels. With the development of novel measurement techniques and improvements in understanding regarding the mechanisms underlying aging-related major neurocognitive disorders, numerous novel biomarkers associated with various aspects of AD neuropathology are being explored. These include specific measurements of Aβ oligomer or monomer forms, tau proteins in the peripheral plasma and CSF, and novel markers of synaptic dysfunction, neuronal damage and apoptosis, neuronal activity alteration, neuroinflammation, blood brain barrier dysfunction, oxidative stress, metabolites, mitochondrial function and aberrant lipid metabolism. The proposed panels of fluid biomarkers may be useful in the early diagnosis of AD, prediction of the progression of AD from preclinical stages to the dementia stage, and the differentiation of AD from non-AD dementia. In combination with physical frailty, the present study surmised that these biomarkers may also be used as biomarkers for CF, thus contribute

  15. Event-related brain potentials to emotional images and gonadal steroid hormone levels in patients with schizophrenia and paired controls

    Directory of Open Access Journals (Sweden)

    Julie eChampagne

    2014-06-01

    Full Text Available Prominent disturbances in the experience, expression, and emotion recognition in patients with schizophrenia have been relatively well documented over the last few years. Furthermore, sex differences in behavior and brain activity, associated with the processing of various emotions, have been reported in the general population and in schizophrenia patients. Others proposed that sex differences should be rather attributed to testosterone, which may play a role in the etiology of schizophrenia. Also, it had been suggested that estradiol may play a protective role in schizophrenia. Surprisingly, few studies investigating this pathology have focused on both brain substrates and gonadal steroid hormone levels, in emotional processing. In the present study, we investigated electrocortical responses related to emotional valence and arousal as well as gonadal steroid hormone levels in patients with schizophrenia. Event-Related Potentials (ERP were recorded during exposition to emotional pictures in 18 patients with schizophrenia and in 24 control participants paired on intelligence, manual dominance and socioeconomic status. Given their previous sensitivity to emotional and attention processes, the P200, N200 and the P300 were selected for analysis. More precisely, emotional valence generally affects early components (N200, which reflect early process of selective attention, whereas emotional arousal and valence both influences the P300 component, which is related to memory context updating, and stimulus categorization. Results showed that, in the control group, the amplitude of the N200 was significantly more lateralized over the right hemisphere, while there was no such lateralization in patients with schizophrenia. In patients with schizophrenia, significantly smaller anterior P300 amplitude was observed to the unpleasant, compared to the pleasant. That anterior P300 reduction was also correlated with negative symptoms.

  16. Persistence of somatic and F-specific coliphages, potential indicators of fecal contamination, on spinach foliar tissue

    Science.gov (United States)

    Introduction: Recent outbreaks of foodborne illness have been linked to consumption of fresh leafy greens. E. coli is commonly used as the indicator microorganism for fecal contamination on growing leafy greens. However, alternative microorganisms, such as coliphages, may be an alternative indicat...

  17. The Brain Activity in Brodmann Area 17: A Potential Bio-Marker to Predict Patient Responses to Antiepileptic Drugs.

    Directory of Open Access Journals (Sweden)

    Yida Hu

    Full Text Available In this study, we aimed to predict newly diagnosed patient responses to antiepileptic drugs (AEDs using resting-state functional magnetic resonance imaging tools to explore changes in spontaneous brain activity. We recruited 21 newly diagnosed epileptic patients, 8 drug-resistant (DR patients, 11 well-healed (WH patients, and 13 healthy controls. After a 12-month follow-up, 11 newly diagnosed epileptic patients who showed a poor response to AEDs were placed into the seizures uncontrolled (SUC group, while 10 patients were enrolled in the seizure-controlled (SC group. By calculating the amplitude of fractional low-frequency fluctuations (fALFF of blood oxygen level-dependent signals to measure brain activity during rest, we found that the SUC patients showed increased activity in the bilateral occipital lobe, particularly in the cuneus and lingual gyrus compared with the SC group and healthy controls. Interestingly, DR patients also showed increased activity in the identical cuneus and lingual gyrus regions, which comprise Brodmann's area 17 (BA17, compared with the SUC patients; however, these abnormalities were not observed in SC and WH patients. The receiver operating characteristic (ROC curves indicated that the fALFF value of BA17 could differentiate SUC patients from SC patients and healthy controls with sufficient sensitivity and specificity prior to the administration of medication. Functional connectivity analysis was subsequently performed to evaluate the difference in connectivity between BA17 and other brain regions in the SUC, SC and control groups. Regions nearby the cuneus and lingual gyrus were found positive connectivity increased changes or positive connectivity changes with BA17 in the SUC patients, while remarkably negative connectivity increased changes or positive connectivity decreased changes were found in the SC patients. Additionally, default mode network (DMN regions showed negative connectivity increased changes or

  18. Evaluation of brain stem auditory evoked potentials in stable patients with chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Gupta Prem

    2008-01-01

    Full Text Available Though there are few studies addressing brainstem auditory evoked potentials (BAEP in patients with chronic obstructive pulmonary disease (COPD, subclinical BAEP abnormalities in stable COPD patients have not been studied. The present study aimed to evaluate the BAEP abnormalities in this study group. Materials and Methods : In the present study, 80 male subjects were included: COPD group comprised 40 smokers with stable COPD with no clinical neuropathy; 40 age-matched healthy volunteers served as the control group. Latencies of BAEP waves I, II, III, IV, and V, together with interpeak latencies (IPLs of I-III, I-V, and III-V, and amplitudes of waves I-Ia and V-Va were studied in both the groups to compare the BAEP abnormalities in COPD group; the latter were correlated with patient characteristics and Mini-Mental Status Examination Questionnaire (MMSEQ scores to seek any significant correlation. Results: Twenty-six (65% of the 40 COPD patients had BAEP abnormalities. We observed significantly prolonged latencies of waves I, III, V over left ear and waves III, IV, V over right ear; increased IPLs of I-V, III-V over left ear and of I-III, I-V, III-V over right side. Amplitudes of waves I-Ia and V-Va were decreased bilaterally. Over left ear, the latencies of wave I and III were significantly correlated with FEV 1 ; and amplitude of wave I-Ia, with smoking pack years. A weak positive correlation between amplitude of wave I-Ia and duration of illness; and a weak negative correlation between amplitude of wave V-Va and MMSEQ scores were seen over right side. Conclusions : We observed significant subclinical BAEP abnormalities on electrophysiological evaluation in studied stable COPD male patients having mild-to-moderate airflow obstruction.

  19. Waste indicators

    International Nuclear Information System (INIS)

    The Waste Indicator Project focuses on methods to evaluate the efficiency of waste management. The project proposes the use of three indicators for resource consumption, primary energy and landfill requirements, based on the life-cycle principles applied in the EDIP Project. Trial runs are made With the indicators on paper, glass packaging and aluminium, and two models are identified for mapping the Danish waste management, of which the least extensive focuses on real and potential savings. (au)

  20. Waste indicators

    Energy Technology Data Exchange (ETDEWEB)

    Dall, O.; Lassen, C.; Hansen, E. [Cowi A/S, Lyngby (Denmark)

    2003-07-01

    The Waste Indicator Project focuses on methods to evaluate the efficiency of waste management. The project proposes the use of three indicators for resource consumption, primary energy and landfill requirements, based on the life-cycle principles applied in the EDIP Project. Trial runs are made With the indicators on paper, glass packaging and aluminium, and two models are identified for mapping the Danish waste management, of which the least extensive focuses on real and potential savings. (au)

  1. Design, synthesis and evaluation of redox radiopharmaceuticals: a potential new approach for the development of brain imaging agents

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, P.C.; Knapp, F.F. Jr.

    1986-01-01

    The fabrication and complete evaluation are described of a dihydropyridine in equilibrium pyridinium salt type redox system for the delivery of radioiodinated agents to the brain. The pivotal intermediate, N-succinimidyl (1-methylpyridinium iodide)-3-carboxylate was prepared by condensation of nicotinic acid and N-hydroxysuccinimide in the presence of dicyclohexylcarbodimide, followed by quaternization of III with methyl iodide. Tissue distribution studies of /sup 125/I-labeled 4-iodoaniline and the redox agents were performed in rats. (/sup 125/I)Iodoaniline initially showed moderate (0.58% dose/gm) brain uptake with subsequent release of the radioactivity from the brain. (/sup 125/I)Iodoaniline, when coupled to a dihydropyridine carrier showed higher uptake and retention in the brain. The (/sup 125/I)iodophenylethyl analogue showed uptake and retention in the brain to be very similar. Apparently the lipophilic agents cross the blood-brain barrier and are oxidized (quaternized) within the brain. The blood-brain barrier then prevents their release resulting in high uptake and retention in the brain and high brain:blood ratios. 11 refs., 3 figs.

  2. Emotion and memory: Event-related potential indices predictive for subsequent successful memory depend on the emotional mood state.

    OpenAIRE

    Kiefer, Markus; Schuch, Stefanie; Schenck, Wolfram; Fiedler, Klaus

    2008-01-01

    The present research investigated the influencesof emotional mood states on cognitive processes and neural circuits during long-term memory encoding using event-related potentials (ERPs). We assessed whether the subsequent memory effect (SME), an electrophysiological index of successful memory encoding, varies as a function of participants’ current mood state. ERPs were recorded while participants in good or bad mood states were presented with words that had to be memorized for subsequent rec...

  3. Male cerebral palsy hospitalization as a potential indicator of neurological effects of methylmercury exposure in Great Lakes communities

    International Nuclear Information System (INIS)

    Perinatal exposure to methylmercury is known to result in severe neurological effects on the developing fetus and infant, including cerebral palsy, mental retardation, and seizures. Males are more susceptible than females to neurological damage from perinatal methylmercury exposures. Preliminary analyses of data and statistics for the hospitalization rates of males for cerebral palsy in the 17 Canadian Areas of Concern in the Great Lakes basin indicate a possible geographic association with locations with elevated mercury from natural or industrial sources

  4. The use of Na+ and K+ ion concentrations as potential diagnostic indicators of subclinical mastitis in dairy cows

    OpenAIRE

    Abdul Wahid Haron; Faez Firdaus Jesse Abdullah; Abdulnasir Tijjani; Yusuf Abba; Lawan Adamu; Konto Mohammed; Aisyah Munira Mohammed Amir; Mohammad Abubakar Sadiq; Mohd Azmi Mohd Lila

    2014-01-01

    Aim: This study was conducted to evaluate the concentrations of sodium (Na+) and potassium (K+) ions in milk of lactating dairy cows with and without subclinical mastitis as putative indicators for detecting subclinical mastitis in dairy cows. Materials and Methods: Thirty seven lactating dairy cows were screened for the evidence of subclinical mastitis using California mastitis test (CMT). The lactating dairy cows were categorized as CMT-Positive (CMT-P; n=20) and CMT-Negative (CMT-N; n=1...

  5. Potential Indicators and Reference Points for Good Environmental Status of Commercially Exploited Marine Fishes and Invertebrates in the German EEZ

    OpenAIRE

    Froese, Rainer; Sampang, Arlene

    2013-01-01

    Indicators and reference points for assessing the good environmental status of commercially exploited marine fishes and invertebrates are presented, using 20 stocks from the German exclusive economic zone. New estimates of length-weight relationship, von Bertalanffy growth, length at 50% and 90% maturity, age at 50% maturity, and length and age where cohort biomass is maximum are presented for each stock. Twice the stock size below which recruitment may become impaired (SSBpa) is proposed as ...

  6. Multislice Cardiac CT-Angiography; A Review on Accepted Indications and Potentials for Other Applications Regarding the Newest Development

    Directory of Open Access Journals (Sweden)

    M. Motevalli

    2007-05-01

    Full Text Available There were not any clear-cut criteria available for clinical use of cardiac CT-angiography (CCTA up to October 2006 in which the American College of Car-diology (ACC, American College of Radiology (ACR and six other medical institutions released a joint consensus on clinical indications of cardiac CT and MRI. A statement was released by the American Heart Association together with two other radiology and cardiology institutions in the same month on the same matter. An illustrated review will be presented on the newly accepted indications of cardiac CT, especially CCTA. Some prominent indications are as follow: 1. Evaluation of chest pain syndrome in patient with intermediate pretest probability of coronary artery disease (CAD when exercise test is not feasible. 2. Evaluation of acute chest pain in patient with in-termediate pretest probability of CAD and negative ECG and enzymes. 3. Uninterpretable or equivocal stress test (exercise, perfusion scan, or stress echo. 4. Evaluation of coronary arteries in patients with new onset heart failure. 5. Assessment of congenital coronary and cardiac anomalies. 6. Noninvasive coronary vein mapping prior to placement of biventricular pacemaker. 7. Noninvasive coronary arterial mapping, including internal mammary artery prior to repeat cardiac sur-gical revascularization. Some recent research indicated that CCTA is useful in some other specific situations too, like evaluating in-stent re-stenosis for stainless steel or cobalt stents more than 3mm in diameter and has also some roles in the evaluation of coronary bypass grafts, etc. Fi-nally, the newer progressions in the field of multislice CT are promising of even better performance which may widen the scope of its indications. Dual-source CT scanners have shown better performance com-pared with 64-slice CT scanners in the preliminary studies, namely slice-thickness of 0.25mm vs. 0.4mm, temporal resolution of 83ms vs.165ms, assessable segments of 98.6% vs. 97

  7. Recording evoked potentials during deep brain stimulation: development and validation of instrumentation to suppress the stimulus artefact

    Science.gov (United States)

    Kent, A. R.; Grill, W. M.

    2012-06-01

    The clinical efficacy of deep brain stimulation (DBS) for the treatment of movement disorders depends on the identification of appropriate stimulation parameters. Since the mechanisms of action of DBS remain unclear, programming sessions can be time consuming, costly and result in sub-optimal outcomes. Measurement of electrically evoked compound action potentials (ECAPs) during DBS, generated by activated neurons in the vicinity of the stimulating electrode, could offer insight into the type and spatial extent of neural element activation and provide a potential feedback signal for the rational selection of stimulation parameters and closed-loop DBS. However, recording ECAPs presents a significant technical challenge due to the large stimulus artefact, which can saturate recording amplifiers and distort short latency ECAP signals. We developed DBS-ECAP recording instrumentation combining commercial amplifiers and circuit elements in a serial configuration to reduce the stimulus artefact and enable high fidelity recording. We used an electrical circuit equivalent model of the instrumentation to understand better the sources of the stimulus artefact and the mechanisms of artefact reduction by the circuit elements. In vitro testing validated the capability of the instrumentation to suppress the stimulus artefact and increase gain by a factor of 1000 to 5000 compared to a conventional biopotential amplifier. The distortion of mock ECAP (mECAP) signals was measured across stimulation parameters, and the instrumentation enabled high fidelity recording of mECAPs with latencies of only 0.5 ms for DBS pulse widths of 50 to 100 µs/phase. Subsequently, the instrumentation was used to record in vivo ECAPs, without contamination by the stimulus artefact, during thalamic DBS in an anesthetized cat. The characteristics of the physiological ECAP were dependent on stimulation parameters. The novel instrumentation enables high fidelity ECAP recording and advances the potential use

  8. Sentinel birds in wild-bird resting sites as potential indicators for West Nile virus infections in Germany.

    Science.gov (United States)

    Ziegler, Ute; Seidowski, Diana; Globig, Anja; Fereidouni, Sasan R; Ulrich, Rainer G; Groschup, Martin H

    2010-06-01

    West Nile virus (WNV) is a mosquito-transmitted flavivirus with wild birds as its natural hosts. Ravens, falcons and jays are highly susceptible for WNV and develop deadly encephalitis, while other bird species undergo only subclinical infections. Migratory birds are efficient vectors for geographic spreading of WNV. Until now, WNV infections have not been diagnosed in Germany, but infections in humans and horses have occurred recently in Austria, Hungary and Italy. To investigate potential WNV introduction by infected wild birds, we have monitored the serological status of ducks in three national sentinel stations. No WNV-positive reactions were found, whereas sera from coots from northern Iran were positive.

  9. Scale-free brain activity: past, present, and future.

    Science.gov (United States)

    He, Biyu J

    2014-09-01

    Brain activity observed at many spatiotemporal scales exhibits a 1/f-like power spectrum, including neuronal membrane potentials, neural field potentials, noninvasive electroencephalography (EEG), magnetoencephalography (MEG), and functional magnetic resonance imaging (fMRI) signals. A 1/f-like power spectrum is indicative of arrhythmic brain activity that does not contain a predominant temporal scale (hence, 'scale-free'). This characteristic of scale-free brain activity distinguishes it from brain oscillations. Although scale-free brain activity and brain oscillations coexist, our understanding of the former remains limited. Recent research has shed light on the spatiotemporal organization, functional significance, and potential generative mechanisms of scale-free brain activity, as well as its developmental and clinical relevance. A deeper understanding of this prevalent brain signal should provide new insights into, and analytical tools for, cognitive neuroscience.

  10. Trends in brain oxygenation during mental and physical exercise measured using near-infrared spectroscopy (NIRS): potential for early detection of Alzheimer's disease

    Science.gov (United States)

    Allen, Monica S.; Allen, Jeffery W.; Mikkilineni, Shweta; Liu, Hanli

    2005-04-01

    Motivation: Early diagnosis of Alzheimer's disease (AD) is crucial because symptoms respond best to available treatments in the initial stages of the disease. Recent studies have shown that marked changes in brain oxygenation during mental and physical tasks can be used for noninvasive functional brain imaging to detect Alzheimer"s disease. The goal of our study is to explore the possibility of using near infrared spectroscopy (NIRS) and mapping (NIRM) as a diagnostic tool for AD before the onset of significant morphological changes in the brain. Methods: A 16-channel NIRS brain imager was used to noninvasively measure spatial and temporal changes in cerebral hemodynamics induced during verbal fluency task and physical activity. The experiments involved healthy subjects (n = 10) in the age range of 25+/-5 years. The NIRS signals were taken from the subjects' prefrontal cortex during the activities. Results and Conclusion: Trends of oxygenated and deoxygenated hemoglobin in the prefrontal cortex of the brain were observed. During the mental stimulation, the subjects showed significant increase in oxygenated hemoglobin [HbO2] with a simultaneous decrease in deoxygenated hemoglobin [Hb]. However, physical exercise caused a rise in levels of HbO2 with small variations in Hb. This study basically demonstrates that NIRM taken from the prefrontal cortex of the human brain is sensitive to both mental and physical tasks and holds potential to serve as a diagnostic means for early detection of Alzheimer's disease.

  11. 脑机接口技术在航天领域的潜在应用%Brain-Machine Interface Technology for Potential Space Application

    Institute of Scientific and Technical Information of China (English)

    杨鑫; 吴边; 陈卫东; 张韶岷; 代建华; 郑筱祥

    2012-01-01

    The space application of brain-machine interface technology may improve the safety and effect of space operations. The current development of non-invasive brain-machine interface technology is addressed, and potential space applications of brain-machine interface are investigated by introducing the most advanced brain signal monitor technology and decoding model. While the brain-machine interface based on Electro-encephalography are always limited to rate, capacity and transmission accuracy, the limitations will be removed gradually with the development of brain-machine interface technology.%脑机接口技术应用于航天领域可提升空间操作的安全性和效率。介绍非植入式脑机接口技术的发展现状,通过引入最新的脑信号监测技术和解码模型,探讨脑机接口技术在航天领域的潜在应用。目前基于头皮脑电的脑机接口方法受限于速度、容量和传输精度,但这些局限会随着该技术的发展而逐渐减小。

  12. DEPRESSION OF THE PHOTIC AFTER DISCHARGE OF FLASH EVOKED POTENTIALS BY PHYSOSTIGMINE, CARBARYL AND PROPOXUR AND THE RELATIONSHIP TO INHIBITION OF BRAIN CHOLINESTERASE

    Science.gov (United States)

    The effects of N-methyl carbamate pesticides on the photic after discharge (PhAD) of flash evoked potentials (FEPs) and the relationship between inhibition of brain cholinesterase (ChE) activity and the PhAD were evaluated. FEPs were recorded in Long Evans rats treated with physo...

  13. Snake pictures draw more early attention than spider pictures in non-phobic women : Evidence from event-related brain potentials

    NARCIS (Netherlands)

    Van Strien, J. W.; Eijlers, R.; Franken, I. H A; Huijding, J.

    2014-01-01

    Snakes were probably the first predators of mammals and may have been important agents of evolutionary changes in the primate visual system allowing rapid visual detection of fearful stimuli (Isbell, 2006). By means of early and late attention-related brain potentials, we examined the hypothesis tha

  14. Snake pictures draw more early attention than spider pictures in non-phobic women: Evidence from event-related brain potentials

    NARCIS (Netherlands)

    J.W. van Strien (Jan); R. Eijlers (R.); I.H.A. Franken (Ingmar); J. Huijding (Jorg)

    2014-01-01

    textabstractSnakes were probably the first predators of mammals and may have been important agents of evolutionary changes in the primate visual system allowing rapid visual detection of fearful stimuli (Isbell, 2006). By means of early and late attention-related brain potentials, we examined the hy

  15. Brewing and volatiles analysis of three tea beers indicate a potential interaction between tea components and lager yeast.

    Science.gov (United States)

    Rong, Lei; Peng, Li-Juan; Ho, Chi-Tang; Yan, Shou-He; Meurens, Marc; Zhang, Zheng-Zhu; Li, Da-Xiang; Wan, Xiao-Chun; Bao, Guan-Hu; Gao, Xue-Ling; Ling, Tie-Jun

    2016-04-15

    Green tea, oolong tea and black tea were separately introduced to brew three kinds of tea beers. A model was designed to investigate the tea beer flavour character. Comparison of the volatiles between the sample of tea beer plus water mixture (TBW) and the sample of combination of tea infusion and normal beer (CTB) was accomplished by triangular sensory test and HS-SPME GC-MS analysis. The PCA of GC-MS data not only showed a significant difference between volatile features of each TBW and CTB group, but also suggested some key compounds to distinguish TBW from CTB. The results of GC-MS showed that the relative concentrations of many typical tea volatiles were significantly changed after the brewing process. More interestingly, the behaviour of yeast fermentation was influenced by tea components. A potential interaction between tea components and lager yeast could be suggested.

  16. Proposed experiments for assessing the potential use of skin as an indicator of sub-erythemal radiation exposure

    International Nuclear Information System (INIS)

    Several biological systems have been developed in recent years for radiation dosimetry. They have proved to be useful in accident situations or when the result of personal dosemeter assessment is equivocal. A review of a range of biochemical and biophysical dosimetry techniques indicates that none are ideally suited for dose assessment in the sub-erythemal range (< 2 Gy) when a high non-uniform or partial body exposure is involved. This important practical situation could be met by the development of a biological dosimetry system based upon the response of skin. A programme of study has been agreed upon to investigate this possibility. A resume of a 1 year pilot study supported by the CEGB is presented, the results of which will be described in due course. (author)

  17. The use of local indicators of spatial association to improve LiDAR-derived predictions of potential amphibian breeding ponds

    Science.gov (United States)

    Julian, J.T.; Young, J.A.; Jones, J.W.; Snyder, C.D.; Wright, C.W.

    2009-01-01

    We examined whether spatially explicit information improved models that use LiDAR return signal intensity to discriminate in-pond habitat from terrestrial habitat at 24 amphibian breeding ponds. The addition of Local Indicators of Spatial Association (LISA) to LiDAR return intensity data significantly improved predictive models at all ponds, reduced residual error by as much as 74%, and appeared to improve models by reducing classification errors associated with types of in-pond vegetation. We conclude that LISA statistics can help maximize the information content that can be extracted from time resolved LiDAR return data in models that predict the occurrence of small, seasonal ponds. ?? Springer-Verlag 2008.

  18. Evaluating the response of biological assemblages as potential indicators for restoration measures in an intermittent Mediterranean river.

    Science.gov (United States)

    Hughes, Samantha Jane; Santos, Jose; Ferreira, Teresa; Mendes, Ana

    2010-08-01

    Bioindicators are essential for detecting environmental degradation and for assessing the success of river restoration initiatives. River restoration projects require the identification of environmental and pressure gradients that affect the river system under study and the selection of suitable indicators to assess habitat quality before, during and after restoration. We assessed the response of benthic macroinvertebrates, fish, bird and macrophyte assemblages to environmental and pressure gradients from sites situated upstream and downstream of a cofferdam on the River Odelouca, an intermittent Mediterranean river in southwest Portugal. The Odelouca will be permanently dammed in 2010. Principal Component Analyses (PCA) of environmental and pressure variables revealed that most variance was explained by environmental factors that clearly separated sites upstream and downstream of the partially built cofferdam. The pressure gradient describing physical impacts to the banks and channel as a result of land use change was less distinct. Redundancy Analysis revealed significant levels of explained variance to species distribution patterns in relation to environmental and pressure variables for all 4 biological assemblages. Partial Redundancy analyses revealed high levels of redundancy for pH between groups and that the avifauna was best associated with pressures acting upon the system. Patterns in invertebrates and fish were associated with descriptors of habitat quality, although fish distribution patterns were affected by reduced connectivity. Procrustean and RELATE (Mantel test) analyses gave broadly similar results and supported these findings. We give suggestions on the suitability of key indicator groups such as benthic macroinvertebrates and endemic fish species to assess in stream habitat quality and appropriate restoration measures, such as the release of peak flow patterns that mimic intermittent Mediterranean systems to combat habitat fragmentation and

  19. Evaluating the Response of Biological Assemblages as Potential Indicators for Restoration Measures in an Intermittent Mediterranean River

    Science.gov (United States)

    Hughes, Samantha Jane; Santos, Jose; Ferreira, Teresa; Mendes, Ana

    2010-08-01

    Bioindicators are essential for detecting environmental degradation and for assessing the success of river restoration initiatives. River restoration projects require the identification of environmental and pressure gradients that affect the river system under study and the selection of suitable indicators to assess habitat quality before, during and after restoration. We assessed the response of benthic macroinvertebrates, fish, bird and macrophyte assemblages to environmental and pressure gradients from sites situated upstream and downstream of a cofferdam on the River Odelouca, an intermittent Mediterranean river in southwest Portugal. The Odelouca will be permanently dammed in 2010. Principal Component Analyses (PCA) of environmental and pressure variables revealed that most variance was explained by environmental factors that clearly separated sites upstream and downstream of the partially built cofferdam. The pressure gradient describing physical impacts to the banks and channel as a result of land use change was less distinct. Redundancy Analysis revealed significant levels of explained variance to species distribution patterns in relation to environmental and pressure variables for all 4 biological assemblages. Partial Redundancy analyses revealed high levels of redundancy for pH between groups and that the avifauna was best associated with pressures acting upon the system. Patterns in invertebrates and fish were associated with descriptors of habitat quality, although fish distribution patterns were affected by reduced connectivity. Procrustean and RELATE (Mantel test) analyses gave broadly similar results and supported these findings. We give suggestions on the suitability of key indicator groups such as benthic macroinvertebrates and endemic fish species to assess in stream habitat quality and appropriate restoration measures, such as the release of peak flow patterns that mimic intermittent Mediterranean systems to combat habitat fragmentation and

  20. The Potential of Forest Biomass Inversion Based on Vegetation Indices Using Multi-Angle CHRIS/PROBA Data

    Directory of Open Access Journals (Sweden)

    Qiang Wang

    2016-10-01

    Full Text Available Multi-angle remote sensing can either be regarded as an added source of uncertainty for variable retrieval, or as a source of additional information, which enhances variable retrieval compared to traditional single-angle observation. However, the magnitude of these angular and band effects for forest structure parameters is difficult to quantify. We used the Discrete Anisotropic Radiative Transfer (DART model and the Zelig model to simulate the forest canopy Bidirectional Reflectance Distribution Factor (BRDF in order to build a look-up table, and eight vegetation indices were used to assess the relationship between BRDF and forest biomass in order to find the sensitive angles and bands. Further, the European Space Agency (ESA mission, Compact High Resolution Imaging Spectrometer onboard the Project for On-board Autonomy (CHRIS-PROBA and field sample measurements, were selected to test the angular and band effects on forest biomass retrieval. The results showed that the off-nadir vegetation indices could predict the forest biomass more accurately than the nadir. Additionally, we found that the viewing angle effect is more important, but the band effect could not be ignored, and the sensitive angles for extracting forest biomass are greater viewing angles, especially around the hot and dark spot directions. This work highlighted the combination of angles and bands, and found a new index based on the traditional vegetation index, Atmospherically Resistant Vegetation Index (ARVI, which is calculated by combining sensitive angles and sensitive bands, such as blue band 490 nm/−55°, green band 530 nm/55°, and the red band 697 nm/55°, and the new index was tested to improve the accuracy of forest biomass retrieval. This is a step forward in multi-angle remote sensing applications for mining the hidden relationship between BRDF and forest structure information, in order to increase the utilization efficiency of remote sensing data.

  1. Is it time to act? The potential of acceptance and commitment therapy for psychological problems following acquired brain injury.

    Science.gov (United States)

    Kangas, Maria; McDonald, Skye

    2011-04-01

    Behaviour therapies have a well-established, useful tradition in psychological treatments and have undergone several major revisions. Acceptance and Commitment Therapy (ACT) and mindfulness-based approaches are considered a third wave of behavioural therapies. Emerging evidence for ACT has demonstrated that this paradigm has promising effectiveness in improving functionality and well-being in a variety of populations that have psychological disturbances and/or medical problems. In this review we first evaluate traditional cognitive behavioural therapy (CBT) interventions used to manage psychological problems in distressed individuals who have sustained an acquired brain injury (ABI). We provide an overview of the ACT paradigm and the existent evidence base for this intervention. A rationale is outlined for why ACT-based interventions may have potential utility in assisting distressed individuals who have sustained a mild to moderate ABI to move forward with their lives. We also review emerging evidence that lends preliminary support to the implementation of acceptance and mindfulness-based interventions in the rehabilitation of ABI patient groups. On the basis of existent literature, we recommend that it is an opportune time for forthcoming research to rigorously test the efficacy of ACT-based interventions in facilitating ABI patient groups to re-engage in living a valued and meaningful life, in spite of their neurocognitive and physical limitations. The promising utility of testing the efficacy of the ACT paradigm in the context of multimodal rehabilitation programmes for ABI populations is also addressed.

  2. Chronic unpredictable stress decreases expression of brain-derived neurotrophic factor (BDNF in mouse ovaries: relationship to oocytes developmental potential.

    Directory of Open Access Journals (Sweden)

    Li-Min Wu

    Full Text Available BACKGROUND: Brain-derived neurotropic factor (BDNF was originally described in the nervous system but has been shown to be expressed in ovary tissues recently, acting as a paracrine/autocrine regulator required for developments of follicles and oocytes. Although it is generally accepted that chronic stress impairs female reproduction and decreases the expression of BDNF in limbic structures of central nervous system, which contributes to mood disorder. However, it is not known whether chronic stress affects oocytes developments, nor whether it affects expression of BDNF in ovary. METHODS: Mice were randomly assigned into control group, stressed group, BDNF-treated group and BDNF-treated stressed group. The chronic unpredictable mild stress model was used to produce psychosocial stress in mice, and the model was verified by open field test and hypothalamic-pituitary-adrenal (HPA axis activity. The methods of immunohistochemistry and western blotting were used to detect BDNF protein level and distribution. The number of retrieved oocytes, oocyte maturation, embryo cleavage and the rates of blastocyst formation after parthenogenetic activation were evaluated. RESULTS: Chronic unpredictable stress decreased the BDNF expression in antral follicles, but didn't affect the BDNF expression in primordial, primary and secondary follicles. Chronic unpredictable stress also decreased the number of retrieved oocytes and the rate of blastocyst formation, which was rescued by exogenous BDNF treatment. CONCLUSION: BDNF in mouse ovaries may be related to the decreased number of retrieved oocytes and impaired oocytes developmental potential induced by chronic unpredictable stress.

  3. [A wireless smart home system based on brain-computer interface of steady state visual evoked potential].

    Science.gov (United States)

    Zhao, Li; Xing, Xiao; Guo, Xuhong; Liu, Zehua; He, Yang

    2014-10-01

    Brain-computer interface (BCI) system is a system that achieves communication and control among humans and computers and other electronic equipment with the electroencephalogram (EEG) signals. This paper describes the working theory of the wireless smart home system based on the BCI technology. We started to get the steady-state visual evoked potential (SSVEP) using the single chip microcomputer and the visual stimulation which composed by LED lamp to stimulate human eyes. Then, through building the power spectral transformation on the LabVIEW platform, we processed timely those EEG signals under different frequency stimulation so as to transfer them to different instructions. Those instructions could be received by the wireless transceiver equipment to control the household appliances and to achieve the intelligent control towards the specified devices. The experimental results showed that the correct rate for the 10 subjects reached 100%, and the control time of average single device was 4 seconds, thus this design could totally achieve the original purpose of smart home system.

  4. Diminished social reward anticipation in the broad autism phenotype as revealed by event-related brain potentials.

    Science.gov (United States)

    Cox, Anthony; Kohls, Gregor; Naples, Adam J; Mukerji, Cora E; Coffman, Marika C; Rutherford, Helena J V; Mayes, Linda C; McPartland, James C

    2015-10-01

    Diminished responsivity to reward incentives is a key contributor to the social-communication problems seen in autism spectrum disorders (ASDs). Social motivation theories suggest that individuals with ASD do not experience social interactions as rewarding, leading to negative consequences for the development of brain circuitry subserving social information. In this study, we examined neural responses to social and non-social reward anticipation in 35 typically developing young adults, examining modulation of reward sensitivity by level of autistic traits. Using an Event-related potential incentive-delay task incorporating novel, more ecologically valid forms of reward, higher expression of autistic traits was associated with an attenuated P3 response to the anticipation of social (simulated real-time video feedback from an observer), but not non-social (candy), rewards. Exploratory analyses revealed that this was unrelated to mentalizing ability. The P3 component reflects motivated attention to reward signals, suggesting attenuated motivation allocation specific to social incentives. The study extends prior findings of atypical reward anticipation in ASD, demonstrating that attenuated social reward responsiveness extends to autistic traits in the range of typical functioning. Results support the development of innovative paradigms for investigating social and non-social reward responsiveness. Insight into vulnerabilities in reward processing is critical for understanding social function in ASD. PMID:25752905

  5. Chronic Fluoxetine Treatment Induces Brain Region-Specific Upregulation of Genes Associated with BDNF-Induced Long-Term Potentiation

    Directory of Open Access Journals (Sweden)

    Maria Nordheim Alme

    2007-01-01

    Full Text Available Several lines of evidence implicate BDNF in the pathogenesis of stress-induced depression and the delayed efficacy of antidepressant drugs. Antidepressant-induced upregulation of BDNF signaling is thought to promote adaptive neuronal plasticity through effects on gene expression, but the effector genes downstream of BDNF has not been identified. Local infusion of BDNF into the dentate gyrus induces a long-term potentiation (BDNF-LTP of synaptic transmission that requires upregulation of the immediate early gene Arc. Recently, we identified five genes (neuritin, Narp, TIEG1, Carp, and Arl4d that are coupregulated with Arc during BDNF-LTP. Here, we examined the expression of these genes in the dentate gyrus, hippocampus proper, and prefrontal cortex after antidepressant treatment. We show that chronic, but not acute, fluoxetine administration leads to upregulation of these BDNF-LTP-associated genes in a brain region-specific pattern. These findings link chronic effects of antidepressant treatment to molecular mechanisms underlying BDNF-induced synaptic plasticity.

  6. Chronic fluoxetine treatment induces brain region-specific upregulation of genes associated with BDNF-induced long-term potentiation.

    Science.gov (United States)

    Alme, Maria Nordheim; Wibrand, Karin; Dagestad, Grethe; Bramham, Clive R

    2007-01-01

    Several lines of evidence implicate BDNF in the pathogenesis of stress-induced depression and the delayed efficacy of antidepressant drugs. Antidepressant-induced upregulation of BDNF signaling is thought to promote adaptive neuronal plasticity through effects on gene expression, but the effector genes downstream of BDNF has not been identified. Local infusion of BDNF into the dentate gyrus induces a long-term potentiation (BDNF-LTP) of synaptic transmission that requires upregulation of the immediate early gene Arc. Recently, we identified five genes (neuritin, Narp, TIEG1, Carp, and Arl4d) that are coupregulated with Arc during BDNF-LTP. Here, we examined the expression of these genes in the dentate gyrus, hippocampus proper, and prefrontal cortex after antidepressant treatment. We show that chronic, but not acute, fluoxetine administration leads to upregulation of these BDNF-LTP-associated genes in a brain region-specific pattern. These findings link chronic effects of antidepressant treatment to molecular mechanisms underlying BDNF-induced synaptic plasticity. PMID:18301726

  7. Event-related potentials in a moving matrix modification of the P300 brain-computer interface paradigm.

    Science.gov (United States)

    Shishkin, Sergei L; Ganin, Ilya P; Kaplan, Alexander Ya

    2011-06-01

    In the standard design of the brain-computer interfaces (BCI) based on the P300 component of the event-related potentials (ERP), target and non-target stimuli are presented at fixed positions in a motionless matrix. Can we let this matrix be moving (e.g., if attached to a robot) without loosing the efficiency of BCI? We assessed changes of the positive peak at Pz in the time interval 300-500 ms after the stimulus onset (P300) and the negative peak at the occipital electrodes in the range 140-240 ms (N1), both important for the operation of the P300 BCI, during fixating a target cell of a moving matrix in healthy participants (n=12). N1 amplitude in the difference (target-non-target) waveforms decreased with the velocity, although remained high (M=-4.3, SD=2.1) even at highest velocity (20°/s). In general, the amplitudes and latencies of these ERP components were remarkably stable in studied types of matrix movement and all velocities of horizontal movement (5, 10 and 20°/s) comparing to matrix in fixed position. These data suggest that, for the users controlling their gaze, the P300 BCI design can be extended to modifications requiring stimuli matrix motion.

  8. The Cognitive Aging of Episodic Memory: A View Based On The Event-Related Brain Potential (ERP

    Directory of Open Access Journals (Sweden)

    David eFriedman

    2013-08-01

    Full Text Available A cardinal feature of older-adult cognition is a decline, relative to the young, in the encoding and retrieval of personally-relevant events, i.e. episodic memory (EM. A consensus holds that familiarity, a relatively automatic feeling of knowing that can support recognition-memory judgments, is preserved with aging. By contrast, recollection, which requires the effortful, strategic recovery of contextual detail, declines as we age. Over the last decade, ERPs have become increasingly important tools in the study of the aging of EM, because a few, well-researched EM effects have been associated with the cognitive processes thought to underlie successful EM performance. EM effects are operationalized by subtracting the ERPs elicited by correctly-rejected, new items from those to correctly recognized, old items. Although highly controversial, the mid-frontal effect (a positive component between ~300 and 500 ms, maximal at fronto-central scalp sites is thought to reflect familiarity-based recognition. A positivity between ~500 and 800 ms, maximal at left-parietal scalp, has been labeled the left-parietal EM effect. A wealth of evidence suggests that this brain activity reflects recollection-based retrieval. Here, I review the ERP evidence in support of the hypothesis that familiarity is maintained while recollection is compromised in older relative to young adults. I consider the possibility that the inconsistency in findings may be due to individual differences in performance, executive function and quality of life indices, such as socio-economic status.

  9. High-frequency combination coding-based steady-state visual evoked potential for brain computer interface

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Feng; Zhang, Xin; Xie, Jun; Li, Yeping; Han, Chengcheng; Lili, Li; Wang, Jing [School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); Xu, Guang-Hua [School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710054 (China)

    2015-03-10

    This study presents a new steady-state visual evoked potential (SSVEP) paradigm for brain computer interface (BCI) systems. The goal of this study is to increase the number of targets using fewer stimulation high frequencies, with diminishing subject’s fatigue and reducing the risk of photosensitive epileptic seizures. The new paradigm is High-Frequency Combination Coding-Based High-Frequency Steady-State Visual Evoked Potential (HFCC-SSVEP).Firstly, we studied SSVEP high frequency(beyond 25 Hz)response of SSVEP, whose paradigm is presented on the LED. The SNR (Signal to Noise Ratio) of high frequency(beyond 40 Hz) response is very low, which is been unable to be distinguished through the traditional analysis method; Secondly we investigated the HFCC-SSVEP response (beyond 25 Hz) for 3 frequencies (25Hz, 33.33Hz, and 40Hz), HFCC-SSVEP produces n{sup n} with n high stimulation frequencies through Frequence Combination Code. Further, Animproved Hilbert-huang transform (IHHT)-based variable frequency EEG feature extraction method and a local spectrum extreme target identification algorithmare adopted to extract time-frequency feature of the proposed HFCC-SSVEP response.Linear predictions and fixed sifting (iterating) 10 time is used to overcome the shortage of end effect and stopping criterion,generalized zero-crossing (GZC) is used to compute the instantaneous frequency of the proposed SSVEP respondent signals, the improved HHT-based feature extraction method for the proposed SSVEP paradigm in this study increases recognition efficiency, so as to improve ITR and to increase the stability of the BCI system. what is more, SSVEPs evoked by high-frequency stimuli (beyond 25Hz) minimally diminish subject’s fatigue and prevent safety hazards linked to photo-induced epileptic seizures, So as to ensure the system efficiency and undamaging.This study tests three subjects in order to verify the feasibility of the proposed method.

  10. The use of Na+ and K+ ion concentrations as potential diagnostic indicators of subclinical mastitis in dairy cows

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    Abdul Wahid Haron

    2014-11-01

    Full Text Available Aim: This study was conducted to evaluate the concentrations of sodium (Na+ and potassium (K+ ions in milk of lactating dairy cows with and without subclinical mastitis as putative indicators for detecting subclinical mastitis in dairy cows. Materials and Methods: Thirty seven lactating dairy cows were screened for the evidence of subclinical mastitis using California mastitis test (CMT. The lactating dairy cows were categorized as CMT-Positive (CMT-P; n=20 and CMT-Negative (CMT-N; n=17 based on whether they were positive or negative for CMT using a standard kit. The CMT-P lactating dairy cows were further sub divided into subclinical 1+ (S1+; n=6, subclinical 2+ (S2+; n=9, and subclinical 3+(S3+; n=5. Direct microscopy somatic cell count (SCC was used to determine the SCC using Wright’s stain. The samples were filtered and diluted at 1:100 dilutions before being measured for the concentrations of Na+ and K+ using atomic absorption spectrophotometer. Results: There was a significant increase (p<0.05 in SCCs and Na+ concentration in the milk of CMT-P dairy cows, with a mean Log10 SCC score of 5.35±0.06 cells/ml and mean Na+ concentration of 232±19.1 mg/dL. However, there was a significant reduction (p<0.05 in the concentration of K+ (123±7.6 mg/dL in the milk samples of the CMT-P cows. There were significant differences (p<0.05 in SCC, Na+ and K+ concentrations between milk samples from the CMT-N dairy cows and CMT-P subgroups; S1+, S2+, and S3+ respectively. Potassium (K+ concentration had a significant strong negative correlation with sodium (Na+ concentration (r=−0.688; p<0.01 and weak positive correlation with SCC (r=−0.436; p<0.01. The sensitivity of using Na+ and K+ concentrations as detection indices for sub-clinical mastitis is 40% and 90%, respectively, while the specificity of each was 100%. Conclusion: This study thus shows that evaluation of Na+ and K+ concentrations from milk samples of dairy cows with sub clinical mastitis

  11. Evidence indicating that meson and baryon formation are controlled by phase space and a linear confining quark potential

    International Nuclear Information System (INIS)

    Using the relativistic string model for hadronization, we find that the two simple principles of longitudinal phase space on the hadron level and a linear confining quark potential as expressed by the 'Wilson Area Law' (a combination of principles from which the Lund Symmetric Fragmentation Function can be derived) describe a great deal of e+e- annihilation data without the need for the many (typically quark-level) parameters such as s/u, vector/All, qq/q, (su/ud)/(s/u), 1/3(qq)1/(qq)0, etc. that are commonly used. In particular, using only 2-3 parameters, we find good agreement with measured meson and baryon multiplicities and longitudinal distributions at Ecm = 29 GeV and at 10 GeV. Typically at 29 GeV a baryon and antibaryon are separated by ∼1.5 mesons in rank. Predictions are extrapolated to 60 GeV (TRISTAN) and 90 GeV (SLC/LEP). Further tests of the model are discussed. (author)

  12. Effects of interstimulus intervals on behavioral, heart rate, and event-related potential indices of infant engagement and sustained attention.

    Science.gov (United States)

    Xie, Wanze; Richards, John E

    2016-08-01

    Maximizing infant attention to stimulus presentation during an EEG or ERP experiment is important for making valid inferences about the neural correlates of infant cognition. The present study examined the effects of stimulus presentation interstimulus interval (ISI) on behavioral and physiological indices of infant attention including infants' fixation to visual presentation, the amount of heart rate (HR) change during sustained attention, and ERP components. This study compared an ISI that is typically used in infant EEG/ERP studies (e.g., 1,500-2,000 ms) with two shorter durations (400-600 ms and 600-1,000 ms). Thirty-six infants were tested cross-sectionally at 3, 4.5, and 6 months. It was found that using the short (400-600 ms) and medium (600-1,000 ms) ISIs resulted in more visually fixated trials and reduced frequency of fixation disengagement per experimental block. We also found larger HR changes during sustained attention to both of the shorter ISIs compared with the long ISI, and larger ERP responses when using the medium ISI compared to using the short and long ISIs. These data suggest that utilizing an optimal ISI (e.g., 600-1,000 ms), which increases the presentation complexity and provides sufficient time for information processing, can promote infant engagement and sustained attention during stimulus presentation. PMID:27159263

  13. Source of and potential bio-indicator for the heavy metal pollution in Ny-(A)lesund, Arctic

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Three kinds of tundra plant samples including Dicranum angnstum(a type of boreal bryophyte) , PuccineUia phryganodes (a type of fringy p/ant),Salix polaris (a type of vascular plant) and surface soil were samples in 200 at Ny-Alesund of the Arctic.The levels of eight heavy metal elements (Hg, Pb, Cd, Cu, Zn, Ni, Fe and Mn) and three metal-like dements (As, Se, Sr) in the plant and soil samples of the areas within previous coal mining activities are significantly higher than those of other areas.The relative accumulation of these elements in these tundra plant samples is consistent with the one in the soft samples, especially in the areas affected by previous coal-mining activities.Thus, the pollution is apparently from local coal mining activity.Dicranum angustum has the highest concentrations among those elements, and it can be a good bio-indicator for heavy metal pollution in Ny(A)lesund.Though Ny(A)lesund is less polluted by heavy metal than nearby Northern European human living areas, but much more than the tundras of the Alaska, Greenland and the Antarctic.

  14. Serum Immunoglobulin A (IgA Level Is a Potential Biomarker Indicating Cirrhosis during Chronic Hepatitis B Infection

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    Sha Lin

    2016-01-01

    Full Text Available Background. Serum immunoglobulins (Igs are frequently elevated in patients with chronic liver disease, but currently there is a lack of sufficient data on serum Igs in patients with chronic hepatitis B virus (CHB infection. This study aimed to evaluate serum IgA, IgG, and IgM levels in patients with HBV-related cirrhosis and to analyze, if altered, immunoglobulin levels that were associated with cirrhosis progress. Methods. A cohort of 174 CHB patients including 104 with cirrhosis (32 decompensated and 72 compensated and 70 without cirrhosis and 55 healthy controls were enrolled. Serum immunoglobulin levels and biochemical and virological parameters were determined in the enrollment blood samples. Results. Serum IgA levels were significantly increased in cirrhosis group compared with noncirrhosis group and healthy controls (all P<0.001. Furthermore, serum IgA concentrations in decompensated cirrhosis patients were significantly higher than that of compensated patients (P=0.002. Multivariate analysis suggested that serum IgA, platelets, and albumin were independent predictors for cirrhosis (all P<0.001. Conclusions. Elevated IgA levels may function as an independent factor indicating cirrhosis, and there appears to be a strong association between increasing serum IgA level and disease progressing in patients with chronic HBV infection.

  15. Description and evaluation of imposex in Strombus canarium Linnaeus, 1758 (Gastropoda, Strombidae): a potential bio-indicator of tributyltin pollution.

    Science.gov (United States)

    Cob, Zaidi Che; Arshad, Aziz; Bujang, Japar Sidik; Abd Ghaffar, Mazlan

    2011-07-01

    Strombus canarium Linnaeus, 1758 is an important gastropod species within the study area and was traditionally collected for food by the locals. The objective of the present study is to assess the incidence of imposex and its severity in this species. Adult conchs were sampled during their main reproductive period, from October 2005 to January 2006, at Sungai Pulai estuary, Johor Straits, Malaysia. A total of 32.81% of adult females showed imposex characteristics, with varying degrees of severity though. The relative penis size (RPS) index ranged from 1.74 to 33.29 (mean = 13.40 ± 2.27, n = 21), while the relative penis length (RPL) index ranged from 6.28 to 55.19 (mean = 25.83 ± 3.33, n = 21). The use of vas deferens sequence (VDS) index was however cannot be applied as the presence of egg groove obscured any vas deferens development in affected females. Sequence of imposex (male penis) development in female conch, from merely a small stump to an advance male penis homologous was therefore carefully analyzed and described, and an alternative imposex classification scheme was proposed. S. canarium can be a good indicator for monitoring of organotin pollution within the study area. However, more studies are needed in order to further develop and test its validity and application, such as its correlation with levels of pollutant within the tissues and the environment, as well as its application on other Strombus species. PMID:20824325

  16. Risk Identification and Forewarning Indicators System of Brain Drain of Employee in the Military Hospital%军队医院聘用制人员流失的风险识别与预警指标体系

    Institute of Scientific and Technical Information of China (English)

    赵育新; 孙令艳; 祝松; 谢峻; 何涛; 李达; 张丽华; 曾艳彩

    2013-01-01

    Objective To identify the risks and forewarn the brain drain of employee in the military hospital. Methods A forewarning indicators system was set up from the angle of the causes of brain drain of employee. Results The established forewarning indicators system was made up of interior and exterior indexes. Conclusion The establishment of forewarning indicators system of brain drain of employee in military hospitals, will be helpful for the hospital managers to take measures to reduce the losses caused by brain drain of employee.%目的 保证军队医院人力资源流失预警管理的科学开展.方法 识别聘用制人员流失风险,从人员流失原因角度建立预警指标体系.结果 建立包括内部预警指标与外部预警指标的预警指标体系.结论 建立军队医院聘用制人员流失风险的预警指标体系,对军队医院及时预控,减少聘用制人员流失带来的损失具有现实意义.

  17. Bacteria as Potential Indicators of Heavy Metal Contamination in a Tropical Mangrove and the Implications on Environmental and Human Health

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    Melanie De La Rosa-Acosta

    2015-09-01

    Full Text Available Heavy metal (HM exposure has been associated with human health diseases like cancer, kidney and liver damage, neurological disorders, motor skills, low bone density and learning problems. With the beginning of the industrialization, the heavy metals in high concentration contribute to putting on the risk the humans in the vicinity. Our study site is located in Cataño, Puerto Rico. This is a highly industrialized area. It is surrounded by a recreational park, a rum distillery, two thermoelectric factories, and was impacted by CAPECO (oil refinery explosion in 2009. Las Cucharillas marsh is part of The San Juan Bay Estuary System, considered as a critical wildlife area. The mangrove marsh has three of the four mangrove species found in PR Laguncularia racemosa, Avicennia germinans and Rhizophora mangle . This study was aimed at seven different heavy metals: Arsenic (As, Cadmium (Cd, Chromium (Cr, Lead (Pb, Zinc (Zn, Mercury (Hg and Copper (Cu. These metals at high concentrations are of human health concern due to their toxicity, persistence, bioaccumulative and bio magnification potentials. Contamination of surface sediments with HM affects the food chain, starting with marine organisms up to humans. The people who live near the contaminated area and the local fishermen are at high risk of exposure. Studies reveal that certain microorganisms can resist the toxicity of heavy metals even at high concentrations. Our study pretends to exploit the sensitive nature of some bacteria to HM and use them as bioindicators. The objective of this research is to assess the bacterial community on the mangrove marsh, identify these bacteria and correlate bacterial species with the type and concentration of the metals found on the site. Our preliminary results with the BIOLOG® identification were five bacteria that are: Carnobacterium inhibens , Cupriavidus gilardii, Enterococcus maloduratus , Microbacterium flavescens and Ralstonia pickettii . This study will

  18. Comparison of brain mechanisms underlying the processing of Chinese characters and pseudo-characters: an event-related potential study.

    Science.gov (United States)

    Wang, Ting; Li, Hong; Zhang, Qinglin; Tu, Shen; Yu, Caiyun; Qiu, Jiang

    2010-04-01

    Most Chinese characters are composed of a semantic radical on the left and a phonetic radical on the right. The semantic radical provides the semantic information; the phonetic radical provides information concerning the pronunciation of the whole character. The pseudo-characters in the study consisted of different sub-lexical parts of real Chinese characters and consequently they also had the semantic radical and the phonetic radical. But they were not readable and had no actual meaning. In order to investigate the spatiotemporal cortical activation patterns underlying the orthographic, phonological and semantic processing of Chinese characters, we used event-related brain potentials (ERPs) to explore the processing of Chinese characters and pseudo-characters when 14 healthy Chinese college students viewed the characters passively. Results showed that both Chinese characters and pseudo-characters elicited an evident negative potential peaking around 120 ms (N120), which appeared to reflect initial orthographic distinction and evaluation. Then, Chinese pseudo-characters elicited a more positive ERP deflection (P220) than did Chinese characters 200-250 ms after onset of the stimuli. It was similar to the recognition potential (RP) and might reflect the integration processes of phonological and semantic processing on the basis of early orthographic information. Dipole source analysis of the difference wave (pseudo-characters minus characters) indicated that a generator localized in the left temporal-occipital junction contributed to this effect, which was possibly related to phonological and perceptual-semantic information integration. Between 350-450 ms, a greater negativity (N360) in pseudo-characters as compared to characters was found over midline fronto-central scalp regions. Dipole analysis localized the generator of N360 in the right parahippocampal cortex. Therefore, the N360 might be an N400 component and reflect the higher-level semantic activation on the

  19. Pharmacological doses of gamma-hydroxybutyrate (GHB) potentiate histone acetylation in the rat brain by histone deacetylase inhibition.

    Science.gov (United States)

    Klein, Christian; Kemmel, Véronique; Taleb, Omar; Aunis, Dominique; Maitre, Michel

    2009-08-01

    Several small chain fatty acids, including butyrate, valproate, phenylbutyrate and its derivatives, inhibit several HDAC activities in the brain at a several hundred micromolar concentration. Gamma-hydroxy-butyrate (GHB), a natural compound found in the brain originating from the metabolism of GABA, is structurally related to these fatty acids. The average physiological tissue concentration of GHB in the brain is below 50 microM, but when GHB is administered or absorbed for therapeutic or recreative purposes, its concentration reaches several hundred micromolars. In the present scenario, we demonstrate that pharmacological concentrations of GHB significantly induce brain histone H3 acetylation with a heterogeneous distribution in the brain and reduce in vitro HDAC activity. The degree of HDAC inhibition was also different according to the region of the brain considered. Taking into account the multiple physiological and functional roles attributed to the modification of histone acetylation and its consequences at the level of gene expression, we propose that part of the therapeutic or toxic effects of high concentrations of GHB in the brain after therapeutic administration of the drug could be partly due to GHB-induced epigenetic factors. In addition, we hypothesize that GHB, being naturally synthesized in the cytosolic compartment of certain neurons, could penetrate into the nuclei and may reach sufficient levels that could significantly modulate histone acetylation and may participate in the epigenetic modification of gene expression.

  20. Retrieval deficiency in brain activity of working memory in amnesic mild cognitive impairment patients: A brain event-related potentials study

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    Binyin eLi

    2016-03-01

    Full Text Available In the early stage of Alzheimer disease (AD or mild cognitive impairment (MCI, working memory (WM deficiency is prominent and could be attributed to failure in encoding, maintenance or retrieval of information. However, evidence for a retention or retrieval deficit remains equivocal. It is also unclear what cognitive mechanism in working memory is impaired in MCI or early AD. We enrolled forty-six subjects from our Memory Clinics and community, with 24 amnesic MCI patients and 22 normal subjects. After neurological and cognitive assessments, they performed a classic delayed match to sample task with simultaneous event-related potential (ERP recorded. The ERPs in encoding and retrieval epoch during WM were analyzed separately. The latency and amplitude of every ERP component were compared between two groups, and then analyzed to explore their relationship with neuropsychological performance. Finally, the locations of maximal difference in cortex were calculated by standard low-resolution tomographic analysis. A total of five components were found: P1, N1, P2, N2 and P300. The amplitude of P2 and P300 was larger in normal subjects than in MCI patients only during retrieval, not encoding epoch, while the latency did not show statistical difference. The latency and amplitude of P1 and N1 were similar in two groups. P2 amplitude in the retrieval epoch positively correlated with memory test (auditory verbal learning test and visual spatial score of Chinese Addenbrooke’s Cognitive Examination-Revised (ACE-R, while P300 amplitude correlated with ACE-R. The activation difference in P2 time range was maximal at medial frontal gyrus. However, the difference in cortex activation during P300 time range did not show significance. The amplitude of P2 indicated deficiency in memory retrieval process, potentially due to dysfunction of central executive in WM model. Regarding the location of P2 during WM task, medial frontal plays important role in memory

  1. Retrieval Deficiency in Brain Activity of Working Memory in Amnesic Mild Cognitive Impairment Patients: A Brain Event-Related Potentials Study.

    Science.gov (United States)

    Li, Bin-Yin; Tang, Hui-Dong; Chen, Sheng-Di

    2016-01-01

    In the early stage of Alzheimer disease (AD) or mild cognitive impairment (MCI), working memory (WM) deficiency is prominent and could be attributed to failure in encoding, maintenance or retrieval of information. However, evidence for a retention or retrieval deficit remains equivocal. It is also unclear what cognitive mechanism in WM is impaired in MCI or early AD. We enrolled 46 subjects from our Memory Clinics and community, with 24 amnesic MCI patients and 22 normal subjects. After neurological and cognitive assessments, they performed a classic delayed match to sample (DMS) task with simultaneous event-related potential (ERP) recorded. The ERPs in encoding and retrieval epoch during WM were analyzed separately. The latency and amplitude of every ERP component were compared between two groups, and then analyzed to explore their relationship with neuropsychological performance. Finally, the locations of maximal difference in cortex were calculated by standard low-resolution tomographic analysis. A total of five components were found: P1, N1, P2, N2, and P300. The amplitude of P2 and P300 was larger in normal subjects than in MCI patients only during retrieval, not encoding epoch, while the latency did not show statistical difference. The latency and amplitude of P1 and N1 were similar in two groups. P2 amplitude in the retrieval epoch positively correlated with memory test (auditory verbal learning test) and visual spatial score of Chinese Addenbrooke's Cognitive Examination-Revised (ACE-R), while P300 amplitude correlated with ACE-R. The activation difference in P2 time range was maximal at medial frontal gyrus. However, the difference in cortex activation during P300 time range did not show significance. The amplitude of P2 indicated deficiency in memory retrieval process, potentially due to dysfunction of central executive in WM model. Regarding the location of P2 during WM task, medial frontal plays important role in memory retrieval. The findings in the

  2. Frontal brain activity and behavioral indicators of affective states are weakly affected by thermal stimuli in sheep living in different housing conditions

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    Sabine eVögeli

    2015-05-01

    Full Text Available Many stimuli evoke short-term emotional reactions. These reactions may play an important role in assessing how a subject perceives a stimulus. Additionally, long-term mood may modulate the emotional reactions but it is still unclear in what way. The question seems to be important in terms of animal welfare, as a negative mood may taint emotional reactions. In the present study with sheep, we investigated the effects of thermal stimuli on emotional reactions and the potential modulating effect of mood induced by manipulations of the housing conditions. We assume that unpredictable, stimulus-poor conditions lead to a negative and predictable, stimulus-rich conditions to a positive mood state. The thermal stimuli were applied to the upper breast during warm ambient temperatures: hot (as presumably negative, intermediate, and cold (as presumably positive. We recorded cortical activity by functional near-infrared spectroscopy, restlessness behavior (e.g. locomotor activity, aversive behaviors and ear postures as indicators of emotional reactions. The strongest hemodynamic reaction was found during a stimulus of intermediate valence independent of the animal’s housing conditions, whereas locomotor activity, ear movements and aversive behaviors were seen most in sheep from the unpredictable, stimulus-poor housing conditions, independent of stimulus valence. We conclude that, sheep perceived the thermal stimuli and differentiated between some of them. An adequate interpretation of the neuronal activity pattern remains difficult, though. The effects of housing conditions were small indicating that the induction of mood was only modestly efficacious. Therefore, a modulating effect of mood on the emotional reaction was not found.

  3. A ¹¹C-labeled 1,4-dihydroquinoline derivative as a potential PET tracer for imaging of redox status in mouse brain.

    Science.gov (United States)

    Okamura, Toshimitsu; Okada, Maki; Kikuchi, Tatsuya; Wakizaka, Hidekatsu; Zhang, Ming-Rong

    2015-12-01

    A disturbance in redox balance has been implicated in the pathogenesis of a number of diseases. This study sought to examine the feasibility of imaging brain redox status using a (11)C-labeled dihydroquinoline derivative ([(11)C]DHQ1) for positron emission tomography (PET). The lipophilic PET tracer [(11)C]DHQ1 was rapidly oxidized to its hydrophilic form in mouse brain homogenate. The redox modulators diphenyleneiodonium and apocynin significantly reduced the initial velocity of [(11)C]DHQ1 oxidation, and apocynin also caused concentration-dependent inhibition of the initial velocity. Moreover, [(11)C]DHQ1 readily entered the brain by diffusion after administration and underwent oxidation into the hydrophilic cationic form, which then slowly decreased. By contrast, apocynin treatment inhibited the in vivo oxidation of [(11)C]DHQ1 to the hydrophilic cationic form, leading to a rapid decrease of radioactivity in the brain. Thus, the difference in the [(11)C]DHQ1 kinetics reflects the alteration in redox status caused by apocynin. In conclusion, [(11)C]DHQ1 is a potential PET tracer for imaging of redox status in the living brain.

  4. Double function of noninvasive intracranial pressure monitoring based on flash visual evoked potentials in unconscious patients with traumatic brain injury.

    Science.gov (United States)

    Wang, Tingzhong; Ma, Shuang; Guan, Yongchang; Du, Jinghua; Liu, Guojun; Zhao, Xianlin

    2016-05-01

    Intracranial pressure (ICP) monitoring based on flash visual evoked potentials (F-VEP) is a noninvasive method of monitoring ICP. The early diagnosis of traumatic optic neuropathy (TON) in unconscious patients with traumatic brain injury (TBI) is a challenge. The aim of this study was to evaluate the function of F-VEP ICP monitoring in predicting TON and detecting contusion enlargement (CE) in unconscious TBI patients using a modified approach. A series of F-VEP ICP-monitored unconscious TBI patients were included in the study. The interocular differences in N2 wave latency (DL) and amplitude (DA) were obtained through monocular flash stimulation. The increases in ICP (dxP) and interchannel difference (dxDC) across various time points were obtained through binocular flash stimulation. The predictive power of DL and DA on TON, as well as of dxP and dxDC on CE, was assessed by logistic regression and receiver operating characteristic (ROC) curve analysis. Patients with TON had a longer DL and a higher DA than those without TON. The dxP and dxDC of patients with CE were both higher than those of patients without CE. The differences were statistically significant. The logistic regression showed that both DL and DA were predictors of TON, whereas only dxDC was a predictor of CE. However, the ROC curve analysis showed that DL had greater predictive power for TON, and dxDC had greater predictive power for CE. An F-VEP ICP monitoring system with a modified approach is beneficial for early diagnosis of TON and prediction of CE in unconscious TBI patients. PMID:26922509

  5. Event-related brain potentials that distinguish false memory for events that occurred only seconds in the past

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    Chen Hong

    2012-07-01

    Full Text Available Abstract Background False memory often involves retrieving events from the distant past that did not actually happen. However, recent evidence obtained using the Deese/Roediger-McDermott (DRM paradigm for eliciting false memory experiences suggests that individuals can falsely believe that events occurred mere seconds in the past when they in fact did not. Subjects in these experiments endorsed unstudied critical lure words as having been studied, despite the fact that word lists were studied just moments before. We identified event-related brain potential (ERP correlates of this experience, and included a repetition priming manipulation to better assess the functional significance of these ERPs. Methods Behavioral and ERP data were collected from 21 Capital Normal University students using a short-term DRM task. Results Two categories of effects were identified that distinguished true from false short-term memory: (1 early semantic priming effects from 300 to 500 ms and (2 later retrieval and retrieval-monitoring effects after 500 ms. The repetition priming manipulation had distinct influences on these effects, consistent with their differential associations with semantic priming versus episodic retrieval. Conclusion Characterization of ERPs related to semantic priming and episodic retrieval provides important information regarding the mechanisms of short-term false memory. In contrast, most studies examining false memory in standard long-delay DRM paradigms identify ERP effects related only to retrieval monitoring. These findings highlight the neural processing involved in illusions of memory after very brief delays and highlight the role of semantic processing in short-term false memory.

  6. Brain-derived neurotrophic factor (BDNF as a potential mechanism of the effects of acute exercise on cognitive performance

    Directory of Open Access Journals (Sweden)

    Aaron T. Piepmeier

    2015-03-01

    Full Text Available The literature shows that improvements in cognitive performance may be observed following an acute bout of exercise. However, evidence in support of the biological mechanisms of this effect is still limited. Findings from both rodent and human studies suggest brain-derived neurotrophic factor (BDNF as a potential mechanism of the effect of acute exercise on memory. The molecular properties of BDNF allow this protein to be assessed in the periphery (pBDNF (i.e., blood serum, blood plasma, making measurements of acute exercise-induced changes in BDNF concentration relatively accessible. Studies exploring the acute exercise–pBDNF–cognitive performance relationship have had mixed findings, but this may be more reflective of methodological differences between studies than it is a statement about the role of BDNF. For example, significant associations have been observed between acute exercise-induced changes in pBDNF concentration and cognitive performance in studies assessing memory, and non-significant associations have been found in studies assessing non-memory cognitive domains. Three suggestions are made for future research aimed at understanding the role of BDNF as a biological mechanism of this relationship: 1 Assessments of cognitive performance may benefit from a focus on various types of memory (e.g., relational, spatial, long-term; 2 More fine-grained measurements of pBDNF will allow for the assessment of concentrations of specific isoforms of the BDNF protein (i.e., immature, mature; 3 Statistical techniques designed to test the mediating role of pBDNF in the acute exercise-cognitive performance relationship should be utilized in order to make causal inferences.

  7. The effect of emotional content on brain activation and the late positive potential in a word n-back task.

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    Juliane Kopf

    Full Text Available INTRODUCTION: There is mounting evidence for the influence of emotional content on working memory performance. This is particularly important in light of the emotion processing that needs to take place when emotional content interferes with executive functions. In this study, we used emotional words of different valence but with similar arousal levels in an n-back task. METHODS: We examined the effects on activation in the prefrontal cortex by means of functional near-infrared spectroscopy (fNIRS and on the late positive potential (LPP. FNIRS and LPP data were examined in 30 healthy subjects. RESULTS: BEHAVIORAL RESULTS SHOW AN INFLUENCE OF VALENCE ON THE ERROR RATE DEPENDING ON THE DIFFICULTY OF THE TASK: more errors were made when the valence was negative and the task difficult. Brain activation was dependent both on the difficulty of the task and on the valence: negative valence of a word diminished the increase in activation, whereas positive valence did not influence the increase in activation, while difficulty levels increased. The LPP also differentiated between the different valences, and in addition was influenced by the task difficulty, the more difficult the task, the less differentiation could be observed. CONCLUSIONS: Summarized, this study shows the influence of valence on a verbal working memory task. When a word contained a negative valence, the emotional content seemed to take precedence in contrast to words containing a positive valence. Working memory and emotion processing sites seemed to overlap and compete for resources even when words are carriers of the emotional content.

  8. Chagas cardiomyopathy: the potential of diastolic dysfunction and brain natriuretic peptide in the early identification of cardiac damage.

    Directory of Open Access Journals (Sweden)

    Ana Garcia-Alvarez

    Full Text Available INTRODUCTION: Chagas disease remains a major cause of mortality in several countries of Latin America and has become a potential public health problem in non-endemic countries as a result of migration flows. Cardiac involvement represents the main cause of mortality, but its diagnosis is still based on nonspecific criteria with poor sensitivity. Early identification of patients with cardiac involvement is desirable, since early treatment may improve prognosis. This study aimed to assess the role of diastolic dysfunction, abnormal myocardial strain and elevated brain natriuretic peptide (BNP in the early identification of cardiac involvement in Chagas disease. METHODOLOGY/PRINCIPAL FINDINGS: Fifty-four patients divided into 3 groups--group 1 (undetermined form: positive serology without ECG or 2D-echocardiographic abnormalities; N = 32, group 2 (typical ECG abnormalities of Chagas disease but normal 2D-echocardiography; N = 14, and group 3 (regional wall motion abnormalities, left ventricular [LV] end-diastolic diameter >55 mm or LV ejection fraction 37 pg/ml were noted in 0%, 13%, 29% and 63% in controls and groups 1 to 3, respectively. Half of patients in the undetermined form had impaired relaxation patterns, whereas half of patients with ECG abnormalities suggestive of Chagas cardiomyopathy had normal diastolic function. In group 1, BNP levels were statistically higher in patients with diastolic dysfunction as compared to those with normal diastolic function (27 ± 26 vs. 11 ± 8 pg/ml, p = 0.03. CONCLUSION/SIGNIFICANCE: In conclusion, the combination of diastolic function and BNP measurement adds important information that could help to better stratify patients with Chagas disease.

  9. A brain-computer interface for potential non-verbal facial communication based on EEG signals related to specific emotions

    OpenAIRE

    Kashihara, Koji

    2014-01-01

    Unlike assistive technology for verbal communication, the brain-machine or brain-computer interface (BMI/BCI) has not been established as a non-verbal communication tool for amyotrophic lateral sclerosis (ALS) patients. Face-to-face communication enables access to rich emotional information, but individuals suffering from neurological disorders, such as ALS and autism, may not express their emotions or communicate their negative feelings. Although emotions may be inferred by looking at facial...

  10. Inhibitory Effect on Cerebral Inflammatory Response following Traumatic Brain Injury in Rats: A Potential Neuroprotective Mechanism of N-Acetylcysteine

    Directory of Open Access Journals (Sweden)

    Gang Chen

    2008-01-01

    Full Text Available Although N-acetylcysteine (NAC has been shown to be neuroprotective for traumatic brain injury (TBI, the mechanisms for this beneficial effect are still poorly understood. Cerebral inflammation plays an important role in the pathogenesis of secondary brain injury after TBI. However, it has not been investigated whether NAC modulates TBI-induced cerebral inflammatory response. In this work, we investigated the effect of NAC administration on cortical expressions of nuclear factor kappa B (NF-κB and inflammatory proteins such as interleukin-1β (IL-1β, tumor necrosis factor-α (TNF-α, interleukin-6 (IL-6, and intercellular adhesion molecule-1 (ICAM-1 after TBI. As a result, we found that NF-κB, proinflammatory cytokines, and ICAM-1 were increased in all injured animals. In animals given NAC post-TBI, NF-κB, IL-1β, TNF-α, and ICAM-1 were decreased in comparison to vehicle-treated animals. Measures of IL-6 showed no change after NAC treatment. NAC administration reduced brain edema, BBB permeability, and apoptotic index in the injured brain. The results suggest that post-TBI NAC administration may attenuate inflammatory response in the injured rat brain, and this may be one mechanism by which NAC ameliorates secondary brain damage following TBI.

  11. Optimizing event-related potential based brain-computer interfaces: a systematic evaluation of dynamic stopping methods

    Science.gov (United States)

    Schreuder, Martijn; Höhne, Johannes; Blankertz, Benjamin; Haufe, Stefan; Dickhaus, Thorsten; Tangermann, Michael

    2013-06-01

    Objective. In brain-computer interface (BCI) research, systems based on event-related potentials (ERP) are considered particularly successful and robust. This stems in part from the repeated stimulation which counteracts the low signal-to-noise ratio in electroencephalograms. Repeated stimulation leads to an optimization problem, as more repetitions also cost more time. The optimal number of repetitions thus represents a data-dependent trade-off between the stimulation time and the obtained accuracy. Several methods for dealing with this have been proposed as ‘early stopping’, ‘dynamic stopping’ or ‘adaptive stimulation’. Despite their high potential for BCI systems at the patient's bedside, those methods are typically ignored in current BCI literature. The goal of the current study is to assess the benefit of these methods. Approach. This study assesses for the first time the existing methods on a common benchmark of both artificially generated data and real BCI data of 83 BCI sessions, allowing for a direct comparison between these methods in the context of text entry. Main results. The results clearly show the beneficial effect on the online performance of a BCI system, if the trade-off between the number of stimulus repetitions and accuracy is optimized. All assessed methods work very well for data of good subjects, and worse for data of low-performing subjects. Most methods, however, are robust in the sense that they do not reduce the performance below the baseline of a simple no stopping strategy. Significance. Since all methods can be realized as a module between the BCI and an application, minimal changes are needed to include these methods into existing BCI software architectures. Furthermore, the hyperparameters of most methods depend to a large extend on only a single variable—the discriminability of the training data. For the convenience of BCI practitioners, the present study proposes linear regression coefficients for directly estimating

  12. Mindfulness training for adolescents: A neurodevelopmental perspective on investigating modifications in attention and emotion regulation using event-related brain potentials.

    Science.gov (United States)

    Sanger, Kevanne Louise; Dorjee, Dusana

    2015-09-01

    Mindfulness training is increasingly being introduced in schools, yet studies examining its impact on the developing brain have been scarce. A neurodevelopmental perspective on mindfulness has been advocated as a powerful tool to enhance our understanding of underlying neurocognitive changes that have implications for developmental well-being research and the implementation of mindfulness in education. To stimulate more research in the developmental cognitive neuroscience of mindfulness, this article outlines possible indexes of mindfulness-based change in adolescence, with a focus on event-related brain potential (ERP) markers. We provide methodological recommendations for future studies and offer examples of research paradigms. We also discuss how mindfulness practice could impact on the development of prefrontal brain structures and enhance attention control and emotion regulation skills in adolescents, impacting in turn on their self-regulation and coping skills. We highlight advantages of the ERP methodology in neurodevelopmental research of mindfulness. It is proposed that research using established experimental tasks targeting ERP components such as the contingent negative variability, N200, error-related negativity and error positivity, P300, and late positive potential could elucidate developmentally salient shifts in the neural plasticity of the adolescent brain induced by mindfulness practice.

  13. Mindfulness training for adolescents: A neurodevelopmental perspective on investigating modifications in attention and emotion regulation using event-related brain potentials.

    Science.gov (United States)

    Sanger, Kevanne Louise; Dorjee, Dusana

    2015-09-01

    Mindfulness training is increasingly being introduced in schools, yet studies examining its impact on the developing brain have been scarce. A neurodevelopmental perspective on mindfulness has been advocated as a powerful tool to enhance our understanding of underlying neurocognitive changes that have implications for developmental well-being research and the implementation of mindfulness in education. To stimulate more research in the developmental cognitive neuroscience of mindfulness, this article outlines possible indexes of mindfulness-based change in adolescence, with a focus on event-related brain potential (ERP) markers. We provide methodological recommendations for future studies and offer examples of research paradigms. We also discuss how mindfulness practice could impact on the development of prefrontal brain structures and enhance attention control and emotion regulation skills in adolescents, impacting in turn on their self-regulation and coping skills. We highlight advantages of the ERP methodology in neurodevelopmental research of mindfulness. It is proposed that research using established experimental tasks targeting ERP components such as the contingent negative variability, N200, error-related negativity and error positivity, P300, and late positive potential could elucidate developmentally salient shifts in the neural plasticity of the adolescent brain induced by mindfulness practice. PMID:25846954

  14. The hunt for brain Aβ oligomers by peripherally circulating multi-functional nanoparticles: Potential therapeutic approach for Alzheimer disease.

    Science.gov (United States)

    Mancini, Simona; Minniti, Stefania; Gregori, Maria; Sancini, Giulio; Cagnotto, Alfredo; Couraud, Pierre-Olivier; Ordóñez-Gutiérrez, Lara; Wandosell, Francisco; Salmona, Mario; Re, Francesca

    2016-01-01

    We previously showed the ability of liposomes bi-functionalized with phosphatidic acid and an ApoE-derived peptide (mApoE-PA-LIP) to reduce brain Aβ in transgenic Alzheimer mice. Herein we investigated the efficacy of mApoE-PA-LIP to withdraw Aβ peptide in different aggregation forms from the brain, using a transwell cellular model of the blood-brain barrier and APP/PS1 mice. The spontaneous efflux of Aβ oligomers (Aβo), but not of Aβ fibrils, from the 'brain' side of the transwell was strongly enhanced (5-fold) in presence of mApoE-PA-LIP in the 'blood' compartment. This effect is due to a withdrawal of Aβo exerted by peripheral mApoE-PA-LIP by sink effect, because, when present in the brain side, they did not act as Aβo carrier and limit the oligomer efflux. In vivo peripheral administration of mApoE-PA-LIP significantly increased the plasma Aβ level, suggesting that Aβ-binding particles exploiting the sink effect can be used as a therapeutic strategy for Alzheimer disease. From the Clinical Editor: Alzheimer disease (AD) at present is an incurable disease, which is thought to be caused by an accumulation of amyloid-β (Aβ) peptides in the brain. Many strategies in combating this disease have been focused on either the prevention or dissolving these peptides. In this article, the authors showed the ability of liposomes bi-functionalized with phosphatidic acid and with an ApoE- derived peptide to withdraw amyloid peptides from the brain. The data would help the future design of more novel treatment for Alzheimer disease.

  15. Integrated use of biomarkers and condition indices in mussels (Mytilus galloprovincialis) for monitoring pollution and development of biomarker index to assess the potential toxic of coastal sites.

    Science.gov (United States)

    Benali, Imene; Boutiba, Zitouni; Merabet, Amina; Chèvre, Nathalie

    2015-06-15

    In this study, we are interested in spatial and temporal variations of the biological and physiological responses of mussels collected from contrasting marine sites regarding their levels of pollution. We measured both the conditions indices and the enzymatic biomarker expression: acetylcholinesterase (AChE), catalase (CAT) and glutathione S-transferase (GST) activity. The enzymatic biomarkers were chosen because they respond to environmental stress. Results show a significant interactions between biomarker variations and conditions indices in the industrial harbor site throughout the seasons. But no significant changes in the reference site. Furthermore, we classified the sites along the seasons according to their potential ecotoxicity, calculated based on the sum of the normalised values of the biomarkers. The results show a very high biomarker index in the impacted site with irregular changes between seasons. This biomarker index is therefore a valuable tool that could be used to classify the toxic potential of coastal sites.

  16. Developing indicators and typologies of frontier-­potential researchers to explore impacts of the ERC’s Starting Independent Researcher Grant

    OpenAIRE

    Thomas, D A

    2011-01-01

    This paper describes a proposed two-stage, controlled, survey-based, research funding impact assessment methodology, developing and testing indicators and typologies of publicly-funded individual researchers more or less likely to undertake research with the potential to become regarded as frontier (‘frontier-potential’ researchers). A baseline stage, online survey questionnaire measurement was addressed to 381 researchers: successful applicants (grantees) to the ‘first cohort’ (2007 call) of...

  17. Dietary Docosahexaenoic Acid Improves Cognitive Function, Tissue Sparing, and Magnetic Resonance Imaging Indices of Edema and White Matter Injury in the Immature Rat after Traumatic Brain Injury.

    Science.gov (United States)

    Schober, Michelle E; Requena, Daniela F; Abdullah, Osama M; Casper, T Charles; Beachy, Joanna; Malleske, Daniel; Pauly, James R

    2016-02-15

    Traumatic brain injury (TBI) is the leading cause of acquired neurologic disability in children. Specific therapies to treat acute TBI are lacking. Cognitive impairment from TBI may be blunted by decreasing inflammation and oxidative damage after injury. Docosahexaenoic acid (DHA) decreases cognitive impairment, oxidative stress, and white matter injury in adult rats after TBI. Effects of DHA on cognitive outcome, oxidative stress, and white matter injury in the developing rat after experimental TBI are unknown. We hypothesized that DHA would decrease early inflammatory markers and oxidative stress, and improve cognitive, imaging and histologic outcomes in rat pups after controlled cortical impact (CCI). CCI or sham surgery was delivered to 17 d old male rat pups exposed to DHA or standard diet for the duration of the experiments. DHA was introduced into the dam diet the day before CCI to allow timely DHA delivery to the pre-weanling pups. Inflammatory cytokines and nitrates/nitrites were measured in the injured brains at post-injury Day (PID) 1 and PID2. Morris water maze (MWM) testing was performed at PID41-PID47. T2-weighted and diffusion tensor imaging studies were obtained at PID12 and PID28. Tissue sparing was calculated histologically at PID3 and PID50. DHA did not adversely affect rat survival or weight gain. DHA acutely decreased oxidative stress and increased anti-inflammatory interleukin 10 in CCI brains. DHA improved MWM performance and lesion volume late after injury. At PID12, DHA decreased T2-imaging measures of cerebral edema and decreased radial diffusivity, an index of white matter injury. DHA improved short- and long-term neurologic outcomes after CCI in the rat pup. Given its favorable safety profile, DHA is a promising candidate therapy for pediatric TBI. Further studies are needed to explore neuroprotective mechanisms of DHA after developmental TBI. PMID:26247583

  18. Microbial Growth, Sensory Characteristic and pH as Potential Spoilage Indicators of Chinese Yellow Wet Noodles from Commercial Processing Plants

    Directory of Open Access Journals (Sweden)

    Suwaibah Ghaffar

    2009-01-01

    Full Text Available Problem statement: This study was conducted to evaluate the potential use of microbial growth, sensory characteristic (odour and pH as potential spoilage indicators of Chinese yellow wet noodles. Approach: Samples were collected from 3 commercial processing plants namely, Automated Processing (AP, Semi-automated Processing (SP and Manual Processing (MP. The samples were kept at ambient temperature (28±2 °C and monitored microbiologically for ten days. Standard Plate Count (TPC and Yeast and Mould Count (YMC were determined using conventional spread plate methods. Sensory evaluation of noodles was carried out using Quantitative Descriptive Analysis (QDA. Results: Initial TPC for all samples were around log 3 CFU/g which significantly increased to around log 7 CFU/g towards the end of storage period. The same pattern was observed for YMC for all samples. Odour of AP, SP and MP samples began to deteriorate and samples became unacceptable to panelists on 3, 4 and 2 days of storage, respectively. Linear regression analyses between storage period and the various potential spoilage indicators demonstrated the strongest correlation for all samples between the storage time and odour (r = 0.81243 - 0.93856 and p=Conclusion/Recommendation: Taken together, odor is the most suitable to be used as spoilage indicator for Chinese yellow wet noodles.

  19. Brain metabolite changes in subcortical regions after exposure to cuprizone for 6 weeks: potential implications for schizophrenia.

    Science.gov (United States)

    Yan, Gen; Xuan, Yinghua; Dai, Zhuozhi; Shen, Zhiwei; Zhang, Guishan; Xu, Haiyun; Wu, Renhua

    2015-01-01

    Cuprizone is a copper chelating agent able to selectively damage the white matter in the mouse brain. Recent studies have reported behavioral abnormalities relevant to some of schizophrenia symptoms. While associating white matter damage to the behavioral abnormalities, these previous studies did not rule out the possible impairment in neuronal functions in cuprizone-exposed mice. The aim of this study was to examine brain metabolites of the cuprizone-exposed mice by proton magnetic resonance spectroscopy ((1)H-MRS). The examined brain regions were the caudoputamen, midbrain, and thalamus; these subcortical regions showed different susceptibilities to cuprizone in terms of demyelination and oligodendrocyte loss in previous studies. Young C57BL/6 mice were fed a standard rodent chow without or with cuprizone (0.2 %) for 6 weeks. At the end, open-field and Y-maze tests were performed to measure the emotional and cognitive behaviors of the animals, followed by (1)H-MRS procedure to evaluate the brain metabolites. Cuprizone-exposure increased anxiety levels and impaired spatial working memory. The same treatment increased T2 signal intensity in the cerebral cortex, hippocampus, and caudoputamen, but not in the thalamus. Cuprizone-exposure decreased the concentrations of NAA and NAA+NAAG in caudoputamen, but not in thalamus and midbrain. It decreased levels of Cr+PCr, GPC+PCh and myo-inositol in all the three brain regions. These results provided neurochemical evidence for the impairment in neuronal functions by cuprizone treatment. PMID:25347963

  20. Electrophysiological manifestations of open- and closed-class words in patients with Broca's aphasia with agrammatic comprehension: An event-related brain potential study

    OpenAIRE

    Ter Keurs, M.; Brown, C.; Hagoort, P.; Stegeman, D

    1999-01-01

    This paper presents electrophysiological data on the on-line processing of open- and closed-class words in patients with Broca’s aphasia with agrammatic comprehension. Event-related brain potentials were recorded from the scalp when Broca patients and nonaphasic control subjects were visually presented with a story in which the words appeared one at a time on the screen. Separate waveforms were computed for open- and closed-class words. The non-aphasic control subjects showed clear difference...

  1. Brain-computer interfaces based on event-related potentials: toward fast, reliable and easy-to-use communication systems for people with neurodegenerative disease

    OpenAIRE

    Kaufmann, Tobias

    2013-01-01

    Objective: Brain Computer Interfaces (BCI) provide a muscle independent interaction channel making them particularly valuable for individuals with severe motor impairment. Thus, different BCI systems and applications have been proposed as assistive technology (AT) solutions for such patients. The most prominent system for communication utilizes event-related potentials (ERP) obtained from the electroencephalogram (EEG) to allow for communication on a character-by-character basis. Yet in their...

  2. Pan-genome analysis of Aeromonas hydrophila, Aeromonas veronii and Aeromonas caviae indicates phylogenomic diversity and greater pathogenic potential for Aeromonas hydrophila.

    Science.gov (United States)

    Ghatak, Sandeep; Blom, Jochen; Das, Samir; Sanjukta, Rajkumari; Puro, Kekungu; Mawlong, Michael; Shakuntala, Ingudam; Sen, Arnab; Goesmann, Alexander; Kumar, Ashok; Ngachan, S V

    2016-07-01

    Aeromonas species are important pathogens of fishes and aquatic animals capable of infecting humans and other animals via food. Due to the paucity of pan-genomic studies on aeromonads, the present study was undertaken to analyse the pan-genome of three clinically important Aeromonas species (A. hydrophila, A. veronii, A. caviae). Results of pan-genome analysis revealed an open pan-genome for all three species with pan-genome sizes of 9181, 7214 and 6884 genes for A. hydrophila, A. veronii and A. caviae, respectively. Core-genome: pan-genome ratio (RCP) indicated greater genomic diversity for A. hydrophila and interestingly RCP emerged as an effective indicator to gauge genomic diversity which could possibly be extended to other organisms too. Phylogenomic network analysis highlighted the influence of homologous recombination and lateral gene transfer in the evolution of Aeromonas spp. Prediction of virulence factors indicated no significant difference among the three species though analysis of pathogenic potential and acquired antimicrobial resistance genes revealed greater hazards from A. hydrophila. In conclusion, the present study highlighted the usefulness of whole genome analyses to infer evolutionary cues for Aeromonas species which indicated considerable phylogenomic diversity for A. hydrophila and hitherto unknown genomic evidence for pathogenic potential of A. hydrophila compared to A. veronii and A. caviae. PMID:27075453

  3. Visual Evoked Potentials to Light Flashes in Captive Rhesus Monkeys: A Study Reflecting Cerebral Cortical Activity and Brain Maturation

    Directory of Open Access Journals (Sweden)

    S.A. Solís-Chávez

    2014-01-01

    Full Text Available Visual evoked potentials (VEPs are useful electrophysiological diagnostic tools for evaluating retinal response of the visual cortex and detecting its functional integrity in humans and animals. To analyze the VEPs and physiologic response of the visual pathway of a random population of captive-bred monkeys of the Macaca mulatta species throughout different physiologic stages after stimulation with stroboscopic light flashes. In this study we used 20 non-human primates (M. mulatta, 10 males and 10 females, divided into five age-dependant cohorts of 2 males and 2 females. Two replicable negative waveforms and one positive were recorded, as reliable indicators of electrical conductivity at specific anatomical nuclei of the visual pathways. Statistically significant differences were primarily observed in group 1 when compared against the remaining groups for the three evaluated waveforms. Waveform morphology characteristically presented steady deviations related to ontogenetic development of the studied population.

  4. On the temporal organization of facial identity and expression analysis: Inferences from event-related brain potentials.

    Science.gov (United States)

    Martens, Ulla; Leuthold, Hartmut; Schweinberger, Stefan R

    2010-12-01

    In the present study, behavioral and electrophysiological markers of information processing-the lateralized readiness potential, the N170, and the P300-were recorded in order to assess the functional and temporal organization of facial identity and expression processing. A two-choice go/no-go task was used in which facial expression (happy vs. angry) determined response hand and response execution depended on facial familiarity (familiar vs. unfamiliar). The duration of facial identity and expression processing was manipulated in separate experiments. Together, the present findings in measures of overt and covert response activation indicate that facial identity is analyzed in parallel with, and typically somewhat faster than, facial expression. These data support a parallel model of face perception that assumes partial output from facial identity and expression processes to motor activation processes. PMID:21098811

  5. Covert effects of "one drink" of alcohol on brain processes related to car driving: an event-related potential study.

    Science.gov (United States)

    Ebe, Kazutoshi; Itoh, Kosuke; Kwee, Ingrid L; Nakada, Tsutomu

    2015-04-23

    The effects of a low dose of alcohol on car driving remain controversial. To address this issue, event-related potentials were recorded while subjects performed a simple car-following task in a driving simulator before and after consuming either "one drink" of beer (representing one standard alcoholic beverage containing 14 g of alcohol) or mineral water (control condition). Subjects who had consumed the determined amount of alcohol demonstrated no detectable outward behavioral signs of intoxication while performing the driving task, an observation in agreement with previous findings. However, the parietal P3 elicited by the brake lights of the preceding car was significantly reduced in amplitude, approximately 50% that observed under the control condition, likely indicating alteration of the neural processing of visual information critical for safe driving. The finding suggests that alcohol begins to affect neural processes for driving even at quantities too low to modify behavior.

  6. ‘Right now, Sophie *swims in the pool?!’: Brain potentials of grammatical aspect processing

    Directory of Open Access Journals (Sweden)

    Monique eFlecken

    2015-11-01

    Full Text Available We investigated whether brain potentials of grammatical aspect processing resemble semantic or morpho-syntactic processing, or whether they instead are characterized by an entirely distinct pattern in the same individuals. We studied aspect from the perspective of agreement between the temporal information in the context (temporal adverbials, e.g., Right now and a morpho-syntactic marker of grammatical aspect (e.g., progressive is swimming. Participants read questions providing a temporal context that was progressive (What is Sophie doing in the pool right now? or habitual (What does Sophie do in the pool every Monday?. Following a lead-in sentence context such as Right now, Sophie…, we measured ERPs time-locked to verb phrases in four different conditions, e.g., (a is swimming (control; (b *is cooking (semantic violation; (c *are swimming (morpho-syntactic violation; or (d?swims (aspect mismatch; …in the pool. The collected ERPs show typical N400 and P600 effects for semantics and morpho-syntax, while aspect processing elicited an Early Negativity (250-350 ms. The aspect-related Negativity was short-lived and had a central scalp distribution with an anterior onset. This differentiates it not only from the semantic N400 effect, but also from the typical (LAN (Left Anterior Negativity, that is frequently reported for various types of agreement processing. Moreover, aspect processing was not accompanied by a clear P600 modulation.We argue that the specific context for each item in this experiment provided a trigger for agreement checking with temporal information encoded on the verb, i.e., morphological aspect marking. The aspect-related Negativity obtained for aspect agreement mismatches reflects a violated expectation concerning verbal inflection (in the example above, the expected verb phrase was Sophie is X-ing rather than Sophie X-s in condition d. The absence of an additional P600 for aspect processing suggests that the mismatch did not

  7. MicroRNAs and their therapeutic potential for human diseases: aberrant microRNA expression in Alzheimer's disease brains.

    Science.gov (United States)

    Satoh, Jun-ichi

    2010-01-01

    MicroRNAs (miRNAs) are a group of small noncoding RNAs that regulate translational repression of multiple target mRNAs. The miRNAs in a whole cell regulate greater than 30% of all protein-coding genes. The vast majority of presently identified miRNAs are expressed in the brain in a spatially and temporally controlled manner. They play a key role in neuronal development, differentiation, and synaptic plasticity. However, at present, the pathological implications of deregulated miRNA expression in neurodegenerative diseases remain largely unknown. This review will briefly summarize recent studies that focus attention on aberrant miRNA expression in Alzheimer's disease brains.

  8. Contribution of harmonicity and location to auditory object formation in free field: Evidence from event-related brain potentials

    Science.gov (United States)

    McDonald, Kelly L.; Alain, Claude

    2005-09-01

    The contribution of location and harmonicity cues in sound segregation was investigated using behavioral reports and source waveforms derived from the scalp-recorded evoked potentials. Participants were presented with sounds composed of multiple harmonics in a free-field environment. The third harmonic was either tuned or mistuned and could be presented from the same or different location from the remaining harmonics. Presenting the third harmonic at a different location than the remaining harmonics increased the likelihood of hearing the tuned or slightly (i.e., 2%) mistuned harmonic as a separate object. Partials mistuned by 16% of their original value ``pop out'' of the complex and were paralleled by an object-related negativity (ORN) that superimposed the N1 and P2 components. For the 2% mistuned stimuli, the ORN was present only when the mistuned harmonic was presented at a different location than the remaining harmonics. Presenting the tuned harmonic at a different location also yielded changes in neural activity between 150 and 250 ms after sound onset. The behavioral and electrophysiological results indicate that listeners can segregate sounds based on harmonicity or location alone. The results also indicate that a conjunction of harmonicity and location cues contribute to sound segregation primarily when harmonicity is ambiguous.

  9. Event-related brain potentials to change in the frequency and temporal structure of sounds in typically developing 5-6-year-old children.

    Science.gov (United States)

    Ervast, Leena; Hämäläinen, Jarmo A; Zachau, Swantje; Lohvansuu, Kaisa; Heinänen, Kaisu; Veijola, Mari; Heikkinen, Elisa; Suominen, Kalervo; Luotonen, Mirja; Lehtihalmes, Matti; Leppänen, Paavo H T

    2015-12-01

    The brain's ability to recognize different acoustic cues (e.g., frequency changes in rapid temporal succession) is important for speech perception and thus for successful language development. Here we report on distinct event-related potentials (ERPs) in 5-6-year-old children recorded in a passive oddball paradigm to repeated tone pair stimuli with a frequency change in the second tone in the pair, replicating earlier findings. An occasional insertion of a third tone within the tone pair generated a more merged pattern, which has not been reported previously in 5-6-year-old children. Both types of deviations elicited pre-attentive discriminative mismatch negativity (MMN) and late discriminative negativity (LDN) responses. Temporal principal component analysis (tPCA) showed a similar topographical pattern with fronto-central negativity for MMN and LDN. We also found a previously unreported discriminative response complex (P340-N440) at the temporal electrode sites at about 140 ms and 240 ms after the frequency deviance, which we suggest reflects a discriminative processing of frequency change. The P340 response was positive with a clear radial distribution preceding the fronto-central frequency MMN by about 30 ms. The results indicate that 5-6-year-old children can detect frequency change and the occasional insertion of an additional tone in sound pairs as reflected by MMN and LDN, even with quite short within-stimulus intervals (150 ms and 50 ms). Furthermore, MMN for these changes is preceded by another response to deviancy, temporal P340, which seems to reflect a parallel but earlier discriminatory process. PMID:26342552

  10. Expression of the human TSPY gene in the brains of transgenic mice suggests a potential role of this Y chromosome gene in neural functions

    Institute of Scientific and Technical Information of China (English)

    Tatsuo Kido; Stephanie Schubert; J(o)rg Schmidtke; Yun-Fai Chris Lau

    2011-01-01

    The testis specific protein Y-encoded (TSPY) is a member of TSPY/SET/NAPl superfamily, encoded within the gonadoblastoma locus on the Y chromosome. TSPY shares a highly conserved SET/NAP-domain responsible for protein-protein interaction among TSPY/SET/NAPl proteins.Accumulating data, so far, support the role of TSPY as the gonadoblastoma gene, involved in germ cell tumorigenesis. The X-chromosome homolog of TSPY, TSPX is expressed in various tissues at both fetal and adult stages, including the brain, and is capable of interacting with the multi-domain adapter protein CASK, thereby influencing the synaptic and transcriptional functions and developmental regulation of CASK in the brain and other neural tissues. Similar to TSPX, we demonstrated that TSPY could interact with CASK at its SET/NAP-domain in cultured cells. Transgenic mice harboring a human TSPY gene and flanking sequences showed specific expression of the human TSPYtransgene in both testis and brain. The neural expression pattern of the human TSPY gene overlapped with those of the endogenous mouse Cask and Tspx gene. Similarly with TSPX, TSPY was co-localized with CASK in neuronal axon fibers in the brain, suggesting a potential role(s) of TSPY in development and/or physiology of the nervous system.

  11. Potential of anti-cancer therapy based on anti-miR-155 oligonucleotides in glioma and brain tumours.

    Science.gov (United States)

    Poltronieri, Palmiro; D'Urso, Pietro I; Mezzolla, Valeria; D'Urso, Oscar F

    2013-01-01

    MicroRNAs are aberrantly expressed in many cancers and can exert tumour-suppressive or oncogenic functions. As oncomirs promote growth of cancer cells and support survival during chemotherapy, thus microRNA-silencing therapies could be a valuable approach to be associated with anticancer drugs and chemotherapy treatments. miR-155 microRNA was found overexpressed in different types of cancer, such as leukaemias (PML, B-cell lymphomas), lung cancer and glioblastoma. GABA-A receptor downregulation was found correlated with glioma grading, with decreasing levels associated with higher grade of malignancies. A relationship between knock-down of miR-155 and re-expression of GABRA 1 protein in vivo was recently individuated. This finding has implication on the effectiveness of RNA-silencing approaches against miR-155 with the scope to control proliferation and signalling pathways regulated by GABA-A receptor. Applying microRNAs for treatment of brain tumours poses several problems, and fields to be solved are mainly the passage of the brain-blood barrier and the targeted delivery to specific cell types. Glioblastoma multiforme cells bud off microvesicles that deliver cytoplasmic contents to nearby cells. Thus, the exploitation of these mechanisms to deliver antagomir therapeutics targeting microvescicles in the brain could take the lead in the near future in the treatment for brain cancers in substitution of invasive surgical intervention. PMID:22834637

  12. The complexity of biomechanics causing primary blast-induced traumatic brain injury: a review of potential mechanisms.

    Directory of Open Access Journals (Sweden)

    Amy eCourtney

    2015-10-01

    Full Text Available Primary blast induced traumatic brain injury (bTBI is a prevalent battlefield injury in recent conflicts, yet biomechanical mechanisms of bTBI remain unclear. Elucidating specific biomechanical mechanisms is essential to developing animal models for testing candidate therapies and for improving protective equipment. Three hypothetical mechanisms of primary bTBI have received the most attention. Because translational and rotational head accelerations are primary contributors to TBI from non-penetrating blunt force head trauma, the acceleration hypothesis suggests that blast-induced head accelerations may cause bTBI. The hypothesis of direct cranial transmission suggests that a pressure transient traverses the skull into the brain and directly injures brain tissue. The thoracic hypothesis of bTBI suggests that some combination of a pressure transient reaching the brain via the thorax and a vagally mediated reflex result in bTBI. These three mechanisms may not be mutually exclusive, and quantifying exposure thresholds (for blasts of a given duration is essential for determining which mechanisms may be contributing for a level of blast exposure. Progress has been hindered by experimental designs which do not effectively expose animal models to a single mechanism and by over-reliance on poorly validated computational models. The path forward should be predictive validation of computational models by quantitative confirmation with blast experiments in animal models, human cadavers, and biofidelic human surrogates over a range of relevant blast magnitudes and durations coupled with experimental designs which isolate a single injury mechanism.

  13. Brain responses evoked by high-frequency repetitive transcranial magnetic stimulation: an event-related potential study

    NARCIS (Netherlands)

    M. Hamidi; H.A. Slagter; G. Tononi; B.R. Postle

    2010-01-01

    Background Many recent studies have used repetitive transcranial magnetic stimulation (rTMS) to study brain-behavior relationships. However, the pulse-to-pulse neural effects of rapid delivery of multiple TMS pulses are unknown largely because of TMS-evoked electrical artifacts limiting recording of

  14. Metabolic Profiling and Enzyme Analyses Indicate a Potential Role of Antioxidant Systems in Complementing Glyphosate Resistance in an Amaranthus palmeri Biotype.

    Science.gov (United States)

    Maroli, Amith S; Nandula, Vijay K; Dayan, Franck E; Duke, Stephen O; Gerard, Patrick; Tharayil, Nishanth

    2015-10-21

    Metabolomics and biochemical assays were employed to identify physiological perturbations induced by a commercial formulation of glyphosate in susceptible (S) and resistant (R) biotypes of Amaranthus palmeri. At 8 h after treatment (HAT), compared to the respective water-treated control, cellular metabolism of both biotypes were similarly perturbed by glyphosate, resulting in abundance of most metabolites including shikimic acid, amino acids, organic acids and sugars. However, by 80 HAT the metabolite pool of glyphosate-treated R-biotype was similar to that of the control S- and R-biotypes, indicating a potential physiological recovery. Furthermore, the glyphosate-treated R-biotype had lower reactive oxygen species (ROS) damage, higher ROS scavenging activity, and higher levels of potential antioxidant compounds derived from the phenylpropanoid pathway. Thus, metabolomics, in conjunction with biochemical assays, indicate that glyphosate-induced metabolic perturbations are not limited to the shikimate pathway, and the oxidant quenching efficiency could potentially complement the glyphosate resistance in this R-biotype.

  15. Metabolic Profiling and Enzyme Analyses Indicate a Potential Role of Antioxidant Systems in Complementing Glyphosate Resistance in an Amaranthus palmeri Biotype.

    Science.gov (United States)

    Maroli, Amith S; Nandula, Vijay K; Dayan, Franck E; Duke, Stephen O; Gerard, Patrick; Tharayil, Nishanth

    2015-10-21

    Metabolomics and biochemical assays were employed to identify physiological perturbations induced by a commercial formulation of glyphosate in susceptible (S) and resistant (R) biotypes of Amaranthus palmeri. At 8 h after treatment (HAT), compared to the respective water-treated control, cellular metabolism of both biotypes were similarly perturbed by glyphosate, resulting in abundance of most metabolites including shikimic acid, amino acids, organic acids and sugars. However, by 80 HAT the metabolite pool of glyphosate-treated R-biotype was similar to that of the control S- and R-biotypes, indicating a potential physiological recovery. Furthermore, the glyphosate-treated R-biotype had lower reactive oxygen species (ROS) damage, higher ROS scavenging activity, and higher levels of potential antioxidant compounds derived from the phenylpropanoid pathway. Thus, metabolomics, in conjunction with biochemical assays, indicate that glyphosate-induced metabolic perturbations are not limited to the shikimate pathway, and the oxidant quenching efficiency could potentially complement the glyphosate resistance in this R-biotype. PMID:26329798

  16. High oxygen consumption rates and scale loss indicate elevated aggressive behaviour at low rearing density, while elevated brain serotonergic activity suggest chronic stress at high rearing densities in farmed rainbow trout Oncorhynchus mykiss

    DEFF Research Database (Denmark)

    Laursen, Danielle Caroline; Silva, P.I.M.; Larsen, Bodil Katrine;

    2013-01-01

    of a previous study,where levels of crowding where determined using the spatial distribution of fish in two-tank systems. An un-crowded low density of 25 kg m−3, the highest density accepted by the fish without showing indications of crowding stress of 80 kg m−3 as the intermediate density, and the highest...... density accepted by the fish showing indications of crowding stress of 140 kg m−3 as the high density were investigated. The aimof the present study was to examine the effect of being held at these densities on indicators of welfare. This was achieved through oxygen consumption measurements using...... automated respirometry, recording fin erosion, determining scale loss and analysing plasma cortisol and brain serotonergic activity levels. The results obtained in the present study indicated that at the lowest density the fish had the space and opportunity to display their natural aggressive behaviour...

  17. The Whole-Brain "Global" Signal from Resting State fMRI as a Potential Biomarker of Quantitative State Changes in Glucose Metabolism.

    Science.gov (United States)

    Thompson, Garth J; Riedl, Valentin; Grimmer, Timo; Drzezga, Alexander; Herman, Peter; Hyder, Fahmeed

    2016-07-01

    The evolution of functional magnetic resonance imaging to resting state (R-fMRI) allows measurement of changes in brain networks attributed to state changes, such as in neuropsychiatric diseases versus healthy controls. Since these networks are observed by comparing normalized R-fMRI signals, it is difficult to determine the metabolic basis of such group differences. To investigate the metabolic basis of R-fMRI network differences within a normal range, eyes open versus eyes closed in healthy human subjects was used. R-fMRI was recorded simultaneously with fluoro-deoxyglucose positron emission tomography (FDG-PET). Higher baseline FDG was observed in the eyes open state. Variance-based metrics calculated from R-fMRI did not match the baseline shift in FDG. Functional connectivity density (FCD)-based metrics showed a shift similar to the baseline shift of FDG, however, this was lost if R-fMRI "nuisance signals" were regressed before FCD calculation. Average correlation with the mean R-fMRI signal across the whole brain, generally regarded as a "nuisance signal," also showed a shift similar to the baseline of FDG. Thus, despite lacking a baseline itself, changes in whole-brain correlation may reflect changes in baseline brain metabolism. Conversely, variance-based metrics may remain similar between states due to inherent region-to-region differences overwhelming the differences between normal physiological states. As most previous studies have excluded the spatial means of R-fMRI metrics from their analysis, this work presents the first evidence of a potential R-fMRI biomarker for baseline shifts in quantifiable metabolism between brain states. PMID:27029438

  18. The characteristic and changes of the event-related potentials (ERP and brain topographic maps before and after treatment with rTMS in subjective tinnitus patients.

    Directory of Open Access Journals (Sweden)

    Haidi Yang

    Full Text Available OBJECTIVES: To compare the event-related potentials (ERPs and brain topographic maps characteristic and change in normal controls and subjective tinnitus patients before and after repetitive transcranial magnetic stimulation (rTMS treatment. METHODS AND PARTICIPANTS: The ERPs and brain topographic maps elicited by target stimulus were compared before and after 1-week treatment with rTMS in 20 subjective tinnitus patients and 16 healthy controls. RESULTS: Before rTMS, target stimulus elicited a larger N1 component than the standard stimuli (repeating soundsin control group but not in tinnitus patients. Instead, the tinnitus group pre-treatment exhibited larger amplitude of N1 in response to standard stimuli than to deviant stimuli. Furthermore tinnitus patients had smaller mismatch negativity (MMN and late discriminative negativity (LDNcomponent at Fz compared with the control group. After rTMS treatment, tinnitus patients showed increased N1 response to deviant stimuli and larger MMN and LDN compared with pre-treatment. The topographic maps for the tinnitus group before rTMS -treatment demonstrated global asymmetry between the left and right cerebral hemispheres with more negative activities in left side and more positive activities in right side. In contrast, the brain topographic maps for patients after rTMS-treatment and controls seem roughly symmetrical. The ERP amplitudes and brain topographic maps in post-treatment patient group showed no significant difference with those in controls. CONCLUSIONS: The characterical changes in ERP and brain topographic maps in tinnitus patients maybe related with the electrophysiological mechanism of tinnitus induction and development. It can be used as an objective biomarker for the evaluation of auditory central in subjective tinnitus patients. These findings support the notion that rTMS treatment in tinnitus patients may exert a beneficial effect.

  19. Evaluation of technetium 99m cyclobutylpropylene amine oxime as a potential brain perfusion imaging agent for SPET

    International Nuclear Information System (INIS)

    99mTc-labelled d,l-cyclobutylpropylene amine oxime (99mTc-CBPAO) has been developed as a brain imaging agent for single photon emission tomography (SPET). 99mTc-CBPAO can be prepared using a simple labelling procedure suitable for routine clinical use. It has a high in vitro stability, as has been demonstrated by high-pressure liquid chromatography (HPCL) analysis. This shows that 3 h after labelling, less than 5% of the primary lipophilic complex which is capable of crossing the blood-brain barrier (BBB) converts to a secondary hydrophilic complex. Brain uptake (% dose/g wet tissue) of 99mTc-CBPAO, determined at 5 and 30 min after injection in two groups of six adult male Sprague-Dawley rats, was found to be 0.74±0.06 and 0.73±0.13 (mean±SD), respectively. These values are not significantly different from those obtained repeating the experiment with 99mTc-labelled hexamethylpropylene amine oxime (99mTc-HMPAO) (0.72±0.15 at 5 min and 0.88±0.24 at 30 min after injection). Since the rat brain uptake of 99mTc-CBPAO remained unchanged for a period of time suitable for tomographic study, the comparison of the two tracers was extended to two groups of ten patients. The latter were affected by neurological and psychiatric disorders and were studied with SPET. Human brain uptake (% dose/cc cortical grey matter) of 99mTc-CBPAO and 99mTc-HMPAO were 3.04±0.57 and 4.22±0.46 (mean x 10-3±SD x 10-3), respectively, with a 32% significant difference. In two other groups of five patients, the first transit time-activity curves of the two tracers were compared. From the analysis of these curves we suggest that 99mTc-CBPAO has a higher binding effect on blood components and/or a higher degradation rate in blood than that of 99mTc-HMPAO. This may account for the reduced human brain uptake. In conclusion, SPET images of 99mTc-CBPAO reflect blood perfusion, and they have a good diagnostic quality. The main advantage of 99mTc-CBPAO is its in vitro stability; however, 99m

  20. FROM BRAIN DRAIN TO BRAIN NETWORKING

    OpenAIRE

    Irina BONCEA

    2015-01-01

    Scientific networking is the most accessible way a country can turn the brain drain into brain gain. Diaspora’s members offer valuable information, advice or financial support from the destination country, without being necessary to return. This article aims to investigate Romania’s potential of turning brain drain into brain networking, using evidence from the medical sector. The main factors influencing the collaboration with the country of origin are investigated. The co...