WorldWideScience

Sample records for brain emerging mechanisms

  1. Mechanical Containment in Emergency

    Directory of Open Access Journals (Sweden)

    Nerea Carcoba Rubio

    2012-09-01

    Full Text Available The restraint is a therapeutic measure aimed at blocking partial or widespread in most of the body of a patient to try to ensure the safety of himself or others. In most cases it forces to act against their will, and in a common context of urgency; in such a way that its use applies a therapeutic plan without the consent of the patient and is temporally deprived of freedom of movement. A literature review of the issue has been performed consulting surveillance systems and protocols developed at hospitals in several spanish cities. Also the current legal regulations on health matters relating to the subject are checked.After the analysis of data and evidence, is created a protocol of restraint in emergency and the various functions of the components of the team, to address the situation with greater efficiency and safe as possible.

  2. Brain mechanisms of emotions.

    Science.gov (United States)

    Simonov, P V

    1997-01-01

    At the 23rd International Congress of Physiology Sciences (Tokyo, 1965) the results of experiment led us to the conclusion that emotions were determined by the actual need and estimation of probability (possibility) of its satisfaction. Low probability of need satisfaction leads to negative emotions actively minimized by the subject. Increased probability of satisfaction, as compared to the earlier forecast, generates positive emotions which the subject tries to maximize, that is, to enhance, to prolong, to repeat. We named our concept the Need-Informational Theory of Emotions. According to this theory, motivation, emotion, and estimation of probability have different neuromorphological substrates. Activation through the hypothalamic motivatiogenic structures of the frontal parts of the neocortex orients the behavior to signals with a high probability of their reinforcement. At the same time the hippocampus is necessary for reactions to signals of low probability events, which are typical for the emotionally excited brain. By comparison of motivational excitation with available stimuli or their engrams, the amygdala selects a dominant motivation, destined to be satisfied in the first instance. In the cases of classical conditioning and escape reaction the reinforcement was related to involvement of the negative emotion's hypothalamic neurons, while in the course of avoidance reaction the positive emotion's neurons were involved. The role of the left and right frontal neocortex in the appearance or positive or negative emotions depends on these informational (cognitive) functions.

  3. Local inhibitory plasticity tunes macroscopic brain dynamics and allows the emergence of functional brain networks.

    Science.gov (United States)

    Hellyer, Peter J; Jachs, Barbara; Clopath, Claudia; Leech, Robert

    2016-01-01

    Rich, spontaneous brain activity has been observed across a range of different temporal and spatial scales. These dynamics are thought to be important for efficient neural functioning. A range of experimental evidence suggests that these neural dynamics are maintained across a variety of different cognitive states, in response to alterations of the environment and to changes in brain configuration (e.g., across individuals, development and in many neurological disorders). This suggests that the brain has evolved mechanisms to maintain rich dynamics across a broad range of situations. Several mechanisms based around homeostatic plasticity have been proposed to explain how these dynamics emerge from networks of neurons at the microscopic scale. Here we explore how a homeostatic mechanism may operate at the macroscopic scale: in particular, focusing on how it interacts with the underlying structural network topology and how it gives rise to well-described functional connectivity networks. We use a simple mean-field model of the brain, constrained by empirical white matter structural connectivity where each region of the brain is simulated using a pool of excitatory and inhibitory neurons. We show, as with the microscopic work, that homeostatic plasticity regulates network activity and allows for the emergence of rich, spontaneous dynamics across a range of brain configurations, which otherwise show a very limited range of dynamic regimes. In addition, the simulated functional connectivity of the homeostatic model better resembles empirical functional connectivity network. To accomplish this, we show how the inhibitory weights adapt over time to capture important graph theoretic properties of the underlying structural network. Therefore, this work presents suggests how inhibitory homeostatic mechanisms facilitate stable macroscopic dynamics to emerge in the brain, aiding the formation of functional connectivity networks. PMID:26348562

  4. The scalable mammalian brain: Emergent distributions of glia and neurons

    NARCIS (Netherlands)

    J.F.M. Jehee; J.M.J. Murre

    2008-01-01

    In this paper, we demonstrate that two characteristic properties of mammalian brains emerge when scaling-up modular, cortical structures. Firstly, the glia-to-neuron ratio is not constant across brains of different sizes: large mammalian brains have more glia per neuron than smaller brains. Our anal

  5. Possible Brain Mechanisms of Creativity.

    Science.gov (United States)

    Heilman, Kenneth M

    2016-06-01

    Creativity is the new discovery, understanding, development and expression of orderly and meaningful relationships. Creativity has three major stages: preparation, the development (nature and nurture) of critical knowledge and skills; innovation, the development of a creative solution; and creative production. Successful preparation requires a basic level of general intelligence and domain specific knowledge and skills and highly creative people may have anatomic alterations of specific neocortical regions. Innovation requires disengagement and divergent thinking primarily mediated by frontal networks. Creative people are often risk-takers and novelty seekers, behaviors that activate their ventral striatal reward system. Innovation also requires associative and convergent thinking, activities that are dependent on the integration of highly distributed networks. People are often most creative when they are in mental states associated with reduced levels of brain norepinephrine, which may enhance the communication between distributed networks. We, however, need to learn more about the brain mechanisms of creativity. PMID:27001974

  6. Possible Brain Mechanisms of Creativity.

    Science.gov (United States)

    Heilman, Kenneth M

    2016-06-01

    Creativity is the new discovery, understanding, development and expression of orderly and meaningful relationships. Creativity has three major stages: preparation, the development (nature and nurture) of critical knowledge and skills; innovation, the development of a creative solution; and creative production. Successful preparation requires a basic level of general intelligence and domain specific knowledge and skills and highly creative people may have anatomic alterations of specific neocortical regions. Innovation requires disengagement and divergent thinking primarily mediated by frontal networks. Creative people are often risk-takers and novelty seekers, behaviors that activate their ventral striatal reward system. Innovation also requires associative and convergent thinking, activities that are dependent on the integration of highly distributed networks. People are often most creative when they are in mental states associated with reduced levels of brain norepinephrine, which may enhance the communication between distributed networks. We, however, need to learn more about the brain mechanisms of creativity.

  7. [Mild brain injuries in emergency medicine].

    Science.gov (United States)

    Liimatainen, Suvi; Niskakangas, Tero; Ohman, Juha

    2011-01-01

    Diagnostics and correct classification of mild brain injuries is challenging. Problems caused by insufficient documentation at the acute phase become more obvious in situations in which legal insurance issues are to be considered. A small proportion of patients with mild brain injury suffer from prolonged symptoms. Medical recording and classification of the brain injury at the initial phase should therefore be carried out in a structured manner. The review deals with the diagnostic problems of mild brain injuries and presents a treatment protocol for adult patients at the acute phase, aiming at avoiding prolonged problems. PMID:22238915

  8. [Mild brain injuries in emergency medicine].

    Science.gov (United States)

    Liimatainen, Suvi; Niskakangas, Tero; Ohman, Juha

    2011-01-01

    Diagnostics and correct classification of mild brain injuries is challenging. Problems caused by insufficient documentation at the acute phase become more obvious in situations in which legal insurance issues are to be considered. A small proportion of patients with mild brain injury suffer from prolonged symptoms. Medical recording and classification of the brain injury at the initial phase should therefore be carried out in a structured manner. The review deals with the diagnostic problems of mild brain injuries and presents a treatment protocol for adult patients at the acute phase, aiming at avoiding prolonged problems.

  9. Synaptic Mechanisms of Blast Induced Brain Injury

    Directory of Open Access Journals (Sweden)

    Andrzej ePrzekwas

    2016-01-01

    Full Text Available Blast wave-induced traumatic brain injury (TBI is one of the most common injuries to military personnel. Brain tissue compression/tension due to blast-induced cranial deformations and shear waves due to head rotation may generate diffuse micro-damage to neuro-axonal structures and trigger a cascade of neurobiological events culminating in cognitive and neurodegenerative disorders. Although diffuse axonal injury is regarded as a signature wound of mild TBI (mTBI, blast loads may also cause synaptic injury wherein neuronal synapses are stretched and sheared. This synaptic injury may result in temporary disconnect of the neural circuitry and transient loss in neuronal communication. We hypothesize that mTBI symptoms such as loss of consciousness or dizziness, which start immediately after the insult could be attributed to synaptic injury. Although empirical evidence is beginning to emerge; the detailed mechanisms underlying synaptic injury are still elusive. Coordinated in vitro - in vivo experiments and mathematical modeling studies can shed light into the synaptic injury mechanisms and their role in the potentiation of mTBI symptoms.

  10. Brain mechanisms of flavor learning

    Directory of Open Access Journals (Sweden)

    Takashi eYamamoto

    2011-09-01

    Full Text Available Once the flavor of the ingested food (conditioned stimulus, CS is associated with a preferable (e.g., good taste or nutritive satisfaction or aversive (e.g., malaise with displeasure signal (unconditioned stimulus, US, animals react to its subsequent exposure by increasing or decreasing ingestion to the food. These two types of association learning (preference learning vs. aversion learning are known as classical conditioned reactions which are basic learning and memory phenomena, leading selection of food and proper food intake. Since the perception of flavor is generated by interaction of taste and odor during food intake, taste and/or odor are mainly associated with bodily signals in the flavor learning. After briefly reviewing flavor learning in general, brain mechanisms of conditioned taste aversion is described in more detail. The CS-US association leading to long-term potentiation in the amygdala, especially in its basolateral nucleus, is the basis of establishment of conditioned taste aversion. The novelty of the CS detected by the cortical gustatory area may be supportive in CS-US association. After the association, CS input is conveyed through the amygdala to different brain regions including the hippocampus for contextual fear formation, to the supramammilary and thalamic paraventricular nuclei for stressful anxiety or memory dependent fearful or stressful emotion, to the reward system to induce aversive expression to the CS, or hedonic shift from positive to negative, and to the CS-responsive neurons in the gustatory system to enhance the responsiveness to facilitate to detect the harmful stimulus.

  11. Collaboration mechanism of intercity emergency rescue ecosystem

    Institute of Scientific and Technical Information of China (English)

    Jiang Yiping; Zhao Lindu

    2009-01-01

    With the development of metropolitan regions and the appearance of urban agglomerations,cities have been more closely related.For the restricted emergency rescue resource in a single city,it has become more and more imminent for the demand of the intercity collaborative resistance to major accident,so as to improve the protection capacity of urban security.In order to find an effective intercity emergency rescue collaborative system,this paper introduces the concept and analysis method of ecosystem theory into intercity emergency rescue.Based on theanalysis of the formation-process of emergency rescue individual,population and community,a three-level intercity emergency rescue collaborative system is constructed according to the characteristics of dynamics and structure of intercity emergency rescue ecosystem,then the collaboration mechanism of information,resource and process in the intercity emergency rescue ecosystem is also studied in this paper,so as to offer available strategy and method for the ecosystem theory applied to intercity emergency rescue.Through the studies of intercity emergency rescue eco,system,it illuminates that the proposed emergency system can not only cope with the major accident more timely and effectively,but also integrate the intercity information resources and emergency rescue resource and process optimi,zation.

  12. Respiratory mechanics in brain injury: A review

    OpenAIRE

    Koutsoukou, Antonia; Katsiari, Maria; Orfanos, Stylianos E; Kotanidou, Anastasia; Daganou, Maria; Kyriakopoulou, Magdalini; Koulouris, Nikolaos G.; Rovina, Nikoletta

    2016-01-01

    Several clinical and experimental studies have shown that lung injury occurs shortly after brain damage. The responsible mechanisms involve neurogenic pulmonary edema, inflammation, the harmful action of neurotransmitters, or autonomic system dysfunction. Mechanical ventilation, an essential component of life support in brain-damaged patients (BD), may be an additional traumatic factor to the already injured or susceptible to injury lungs of these patients thus worsening lung injury, in case ...

  13. Melanoma Brain Metastasis: Mechanisms, Models, and Medicine.

    Science.gov (United States)

    Kircher, David A; Silvis, Mark R; Cho, Joseph H; Holmen, Sheri L

    2016-01-01

    The development of brain metastases in patients with advanced stage melanoma is common, but the molecular mechanisms responsible for their development are poorly understood. Melanoma brain metastases cause significant morbidity and mortality and confer a poor prognosis; traditional therapies including whole brain radiation, stereotactic radiotherapy, or chemotherapy yield only modest increases in overall survival (OS) for these patients. While recently approved therapies have significantly improved OS in melanoma patients, only a small number of studies have investigated their efficacy in patients with brain metastases. Preliminary data suggest that some responses have been observed in intracranial lesions, which has sparked new clinical trials designed to evaluate the efficacy in melanoma patients with brain metastases. Simultaneously, recent advances in our understanding of the mechanisms of melanoma cell dissemination to the brain have revealed novel and potentially therapeutic targets. In this review, we provide an overview of newly discovered mechanisms of melanoma spread to the brain, discuss preclinical models that are being used to further our understanding of this deadly disease and provide an update of the current clinical trials for melanoma patients with brain metastases. PMID:27598148

  14. Emergency treatment options for pediatric traumatic brain injury

    OpenAIRE

    Exo, J; Smith, C.; Smith, R.; Bell, MJ

    2009-01-01

    Traumatic brain injury is a leading killer of children and is a major public health problem around the world. Using general principles of neurocritical care, various treatment strategies have been developed to attempt to restore homeostasis to the brain and allow brain healing, including mechanical factors, cerebrospinal fluid diversion, hyperventilation, hyperosmolar therapies, barbiturates and hypothermia. Careful application of these therapies, normally in a step-wise fashion as intracrani...

  15. The biological significance of brain barrier mechanisms

    DEFF Research Database (Denmark)

    Saunders, Norman R; Habgood, Mark D; Møllgård, Kjeld;

    2016-01-01

    toxins, drugs, and other xenobiotics. In this review, we summarize these influx and efflux mechanisms in normal developing and adult brain, as well as indicating their likely involvement in a wide range of neuropathologies. There have been extensive attempts to overcome the barrier mechanisms...... that prevent the entry of many drugs of therapeutic potential into the brain. We outline those that have been tried and discuss why they may so far have been largely unsuccessful. Currently, a promising approach appears to be focal, reversible disruption of the blood-brain barrier using focused ultrasound......, but more work is required to evaluate the method before it can be tried in patients. Overall, our view is that much more fundamental knowledge of barrier mechanisms and development of new experimental methods will be required before drug targeting to the brain is likely to be a successful endeavor...

  16. Brain mechanisms underlying human communication

    Directory of Open Access Journals (Sweden)

    Matthijs L Noordzij

    2009-07-01

    Full Text Available Human communication has been described as involving the coding-decoding of a conventional symbol system, which could be supported by parts of the human motor system (i.e. the “mirror neurons system”. However, this view does not explain how these conventions could develop in the first place. Here we target the neglected but crucial issue of how people organize their non-verbal behavior to communicate a given intention without pre-established conventions. We have measured behavioral and brain responses in pairs of subjects during communicative exchanges occurring in a real, interactive, on-line social context. In two fMRI studies, we found robust evidence that planning new communicative actions (by a sender and recognizing the communicative intention of the same actions (by a receiver relied on spatially overlapping portions of their brains (the right posterior superior temporal sulcus. The response of this region was lateralized to the right hemisphere, modulated by the ambiguity in meaning of the communicative acts, but not by their sensorimotor complexity. These results indicate that the sender of a communicative signal uses his own intention recognition system to make a prediction of the intention recognition performed by the receiver. This finding supports the notion that our communicative abilities are distinct from both sensorimotor processes and language abilities.

  17. The biological significance of brain barrier mechanisms

    DEFF Research Database (Denmark)

    Saunders, Norman R; Habgood, Mark D; Møllgård, Kjeld;

    2016-01-01

    cells, and tanycytes (specialized glial cells) in the circumventricular organs. In the ependyma lining the cerebral ventricles in the adult brain, the cells are joined by gap junctions, which are not restrictive for intercellular movement of molecules. But in the developing brain, the forerunners...... structures are physiological mechanisms as the cells of the interfaces contain various metabolic transporters and efflux pumps, often ATP-binding cassette (ABC) transporters, that provide an important component of the barrier functions by either preventing entry of or expelling numerous molecules including......Barrier mechanisms in the brain are important for its normal functioning and development. Stability of the brain's internal environment, particularly with respect to its ionic composition, is a prerequisite for the fundamental basis of its function, namely transmission of nerve impulses...

  18. [The brain mechanisms of emotions].

    Science.gov (United States)

    Simonov, P V

    1997-01-01

    At the 23rd International Congress of Physiological Sciences (Tokyo, 1965) the results of experiment brought us to a conclusion that emotions were determined by the actual need and estimation of probability (possibility) of its satisfaction. Low probability of need satisfaction leads to negative emotions actively minimized by the subject. Increased probability of satisfaction, as compared to the earlier forecast, generates positive emotions which the subject tries to maximize, that is to enhance, to prolong, to repeat. We named our concept the Need-Informational Theory of Emotions. According to this theory, motivation, emotion and estimation of probability have different neuromorphological substrate. Activating by motivatiogenic structures of the hypothalamus the frontal parts of neocortex orients the behavior to signals with a high probability of their reinforcement. At the same time the hippocampus is necessary for reactions to signals of low probability events, which is typical for emotionally excited brain. By comparison of motivational excitation with available stimuli or their engrams the amygdala selects a dominant motivation, destined to be satisfied in the first instance. In the cases of classical conditioning and escape reaction the reinforcement was related to involvement of the negative emotion's hypothalamic neurons while in the course of avoidance reaction the positive emotion's neurons being involved. The role of the left and right frontal neocortex in the appearance of positive or negative emotions depends on this informational (cognitive) functions.

  19. Uncovering the mechanism(s) of deep brain stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Li Gang; Yu Chao; Lin Ling; Lu, Stephen C-Y [Inspiring Technical Laboratory, College of Precision Instruments and Opto-Electronics Engineering, Tianjin University, Tianjin 300072 (China)

    2005-01-01

    Deep brain stimulators, often called 'pacemakers for the brain', are implantable devices which continuously deliver impulse stimulation to specific targeted nuclei of deep brain structure, namely deep brain stimulation (DBS). To date, deep brain stimulation (DBS) is the most effective clinical technique for the treatment of several medically refractory movement disorders (e.g., Parkinson's disease, essential tremor, and dystonia). In addition, new clinical applications of DBS for other neurologic and psychiatric disorders (e.g., epilepsy and obsessive-compulsive disorder) have been put forward. Although DBS has been effective in the treatment of movement disorders and is rapidly being explored for the treatment of other neurologic disorders, the scientific understanding of its mechanisms of action remains unclear and continues to be debated in the scientific community. Optimization of DBS technology for present and future therapeutic applications will depend on identification of the therapeutic mechanism(s) of action. The goal of this review is to address our present knowledge of the effects of high-frequency stimulation within the central nervous system and comment on the functional implications of this knowledge for uncovering the mechanism(s) of DBS.

  20. Uncovering the mechanism(s) of deep brain stimulation

    Science.gov (United States)

    Gang, Li; Chao, Yu; Ling, Lin; C-Y Lu, Stephen

    2005-01-01

    Deep brain stimulators, often called `pacemakers for the brain', are implantable devices which continuously deliver impulse stimulation to specific targeted nuclei of deep brain structure, namely deep brain stimulation (DBS). To date, deep brain stimulation (DBS) is the most effective clinical technique for the treatment of several medically refractory movement disorders (e.g., Parkinson's disease, essential tremor, and dystonia). In addition, new clinical applications of DBS for other neurologic and psychiatric disorders (e.g., epilepsy and obsessive-compulsive disorder) have been put forward. Although DBS has been effective in the treatment of movement disorders and is rapidly being explored for the treatment of other neurologic disorders, the scientific understanding of its mechanisms of action remains unclear and continues to be debated in the scientific community. Optimization of DBS technology for present and future therapeutic applications will depend on identification of the therapeutic mechanism(s) of action. The goal of this review is to address our present knowledge of the effects of high-frequency stimulation within the central nervous system and comment on the functional implications of this knowledge for uncovering the mechanism(s) of DBS.

  1. Mechanism of action of levonorgestrel emergency contraception.

    Science.gov (United States)

    Kahlenborn, Chris; Peck, Rebecca; Severs, Walter B

    2015-02-01

    There has been much debate regarding levonorgestrel emergency contraception's (LNG-EC's) method of action since 1999 when the Food and Drug Administration first approved its use. Proponents of LNG-EC have argued that they have moral certitude that LNG-EC works via a non-abortifacient mechanism of action, and claim that all the major scientific and medical data consistently support this hypothesis. However, newer medical data serve to undermine the consistency of the non-abortifacient hypothesis and instead support the hypothesis that preovulatory administration of LNG-EC has significant potential to work via abortion. The implications of the newer data have important ramifications for medical personnel, patients, and both Catholic and non-Catholic emergency room protocols. In the future, technology such as the use of early pregnancy factor may have the potential to quantify how frequently preovulatory LNG-EC works via abortion. Lay Summary: How Plan B (levonorgestrel emergency contraception) works has been vigorously debated ever since the Food and Drug Administration approved it in 1999. Many doctors and researchers claim that it has either no-or at most-an extremely small chance of working via abortion. However, the latest scientific and medical evidence now demonstrates that levonorgestrel emergency contraception theoretically works via abortion quite often. The implications of the newer data have important ramifications for medical personnel, patients, and both Catholic and non-Catholic emergency room rape protocols. PMID:25698840

  2. Hydrogels for brain repair after stroke: an emerging treatment option.

    OpenAIRE

    Nih, LR; Carmichael, ST; Segura, T

    2016-01-01

    Stroke disability is the only major disease without an effective treatment. The substantial clinical burden of stroke in disabled survivors and the lack of a medical therapy that promotes recovery provide an opportunity to explore the use of biomaterials to promote brain repair after stroke. Hydrogels can be injected as a liquid and solidify in situ to form a gelatinous solid with similar mechanical properties to the brain. These biomaterials have been recently explored to generate pro-repair...

  3. Emergent mechanics, quantum and un-quantum

    Science.gov (United States)

    Ralston, John P.

    2013-10-01

    There is great interest in quantum mechanics as an "emergent" phenomenon. The program holds that nonobvious patterns and laws can emerge from complicated physical systems operating by more fundamental rules. We find a new approach where quantum mechanics itself should be viewed as an information management tool not derived from physics nor depending on physics. The main accomplishment of quantum-style theory comes in expanding the notion of probability. We construct a map from macroscopic information as data" to quantum probability. The map allows a hidden variable description for quantum states, and efficient use of the helpful tools of quantum mechanics in unlimited circumstances. Quantum dynamics via the time-dependent Shroedinger equation or operator methods actually represents a restricted class of classical Hamiltonian or Lagrangian dynamics, albeit with different numbers of degrees of freedom. We show that under wide circumstances such dynamics emerges from structureless dynamical systems. The uses of the quantum information management tools are illustrated by numerical experiments and practical applications

  4. Recovery after Brain Injury: Mechanisms and Principles

    Directory of Open Access Journals (Sweden)

    Randolph J. Nudo

    2013-12-01

    Full Text Available The past 20 years have represented an important period in the development of principles underlying neuroplasticity, especially as they apply to recovery from neurological injury. It is now generally accepted that acquired brain injuries, such as occur in stroke or trauma, initiate a cascade of regenerative events that last for at least several weeks, if not months. Many investigators have pointed out striking parallels between post-injury plasticity and the molecular and cellular events that take place during normal brain development. As evidence for the principles and mechanisms underlying post-injury neuroplasticity has been gleaned from both animal models and human populations, novel approaches to therapeutic intervention have been proposed. One important theme has persisted as the sophistication of clinicians and scientists in their knowledge of neuroplasticity mechanisms has grown: Behavioral experience is the most potent modulator of brain plasticity. While there is substantial evidence for this principle in normal, healthy brains, the injured brain is particularly malleable. Based on the quantity and quality of motor experience, the brain can be reshaped after injury in either adaptive or maladaptive ways. This paper reviews selected studies that have demonstrated the neurophysiological and neuroanatomical changes that are triggered by motor experience, by injury, and the interaction of these processes. In addition, recent studies using new and elegant techniques are providing novel perspectives on the events that take place in the injured brain, providing a real-time window into post-injury plasticity. These new approaches are likely to accelerate the pace of basic research, and provide a wealth of opportunities to translate basic principles into therapeutic methodologies.

  5. The role of mechanics during brain development

    Science.gov (United States)

    Budday, Silvia; Steinmann, Paul; Kuhl, Ellen

    2014-12-01

    Convolutions are a classical hallmark of most mammalian brains. Brain surface morphology is often associated with intelligence and closely correlated with neurological dysfunction. Yet, we know surprisingly little about the underlying mechanisms of cortical folding. Here we identify the role of the key anatomic players during the folding process: cortical thickness, stiffness, and growth. To establish estimates for the critical time, pressure, and the wavelength at the onset of folding, we derive an analytical model using the Föppl-von Kármán theory. Analytical modeling provides a quick first insight into the critical conditions at the onset of folding, yet it fails to predict the evolution of complex instability patterns in the post-critical regime. To predict realistic surface morphologies, we establish a computational model using the continuum theory of finite growth. Computational modeling not only confirms our analytical estimates, but is also capable of predicting the formation of complex surface morphologies with asymmetric patterns and secondary folds. Taken together, our analytical and computational models explain why larger mammalian brains tend to be more convoluted than smaller brains. Both models provide mechanistic interpretations of the classical malformations of lissencephaly and polymicrogyria. Understanding the process of cortical folding in the mammalian brain has direct implications on the diagnostics of neurological disorders including severe retardation, epilepsy, schizophrenia, and autism.

  6. The neuroprotective mechanism of brain ischemic preconditioning

    Institute of Scientific and Technical Information of China (English)

    Xiao-qian LIU; Rui SHENG; Zheng-hong QIN

    2009-01-01

    Brain ischemia is one of the most common causes of death and the leading cause of adult disability in the world. Brain ischemic pre- conditioning (BIP) refers to a transient, sublethal ischemia which results in tolerance to later, otherwise lethal, cerebral ischemia. Many attempts have been made to understand the molecular and cellular mechanisms underlying the neuroprotection offered by ischemic preconditioning. Many studies have shown that neuroprotective mechanisms may involve a series of molecular regulatory pathways including activation of the N-methyI-D-aspartate (NMDA) and adenosine receptors; activation of intracellular signaling pathways such as mitogen activated protein kinases (MAPK) and other protein kinases; upregulation of Bcl-2 and heat shock proteins (HSPs); and activation of the ubiquitin-proteasome pathway and the autophagic-lysosomal pathway. A better understanding of the processes that lead to cell death after stroke as well as of the endogenous neuroprotective mechanisms by which BIP protects against brain ischemic insults could help to develop new therapeutic strategies for this devastating neurological disease. The purpose of the present review is to summarize the neuroprotective mechanisms of BIP and to discuss the possibility of mimicking ischemic preconditioning as a new strategy for preventive treatment of ischemia.

  7. Respiratory mechanics in brain injury: A review.

    Science.gov (United States)

    Koutsoukou, Antonia; Katsiari, Maria; Orfanos, Stylianos E; Kotanidou, Anastasia; Daganou, Maria; Kyriakopoulou, Magdalini; Koulouris, Nikolaos G; Rovina, Nikoletta

    2016-02-01

    Several clinical and experimental studies have shown that lung injury occurs shortly after brain damage. The responsible mechanisms involve neurogenic pulmonary edema, inflammation, the harmful action of neurotransmitters, or autonomic system dysfunction. Mechanical ventilation, an essential component of life support in brain-damaged patients (BD), may be an additional traumatic factor to the already injured or susceptible to injury lungs of these patients thus worsening lung injury, in case that non lung protective ventilator settings are applied. Measurement of respiratory mechanics in BD patients, as well as assessment of their evolution during mechanical ventilation, may lead to preclinical lung injury detection early enough, allowing thus the selection of the appropriate ventilator settings to avoid ventilator-induced lung injury. The aim of this review is to explore the mechanical properties of the respiratory system in BD patients along with the underlying mechanisms, and to translate the evidence of animal and clinical studies into therapeutic implications regarding the mechanical ventilation of these critically ill patients. PMID:26855895

  8. The Emergent Copenhagen Interpretation of Quantum Mechanics

    CERN Document Server

    Hollowood, Timothy J

    2013-01-01

    We introduce a new and conceptually simple interpretation of quantum mechanics based on reduced density matrices of sub-systems from which the standard Copenhagen interpretation emerges as an effective description of macroscopically large systems. Wave function collapse is seen to be a useful but fundamentally unnecessary piece of prudent book keeping which is only valid for macro-systems. The new interpretation lies in a class of modal interpretations in that it applies to quantum systems that interact with a much larger environment. However, we show that it does not suffer from the problems that have plagued similar modal interpretations like macroscopic superpositions and rapid flipping between macroscopically distinct states. We describe how the interpretation fits neatly together with fully quantum formulations of statistical mechanics and that a measurement process can be viewed as a process of ergodicity breaking analogous to a phase transition. The key feature of the new interpretation is that joint p...

  9. Biophysical mechanisms of traumatic brain injuries.

    Science.gov (United States)

    Young, Lee Ann; Rule, Gregory T; Bocchieri, Robert T; Burns, Jennie M

    2015-02-01

    Despite years of effort to prevent traumatic brain injuries (TBIs), the occurrence of TBI in the United States alone has reached epidemic proportions. When an external force is applied to the head, it is converted into stresses that must be absorbed into the brain or redirected by a helmet or other protective equipment. Complex interactions of the head, neck, and jaw kinematics result in strains in the brain. Even relatively mild mechanical trauma to these tissues can initiate a neurochemical cascade that leads to TBI. Civilians and warfighters can experience head injuries in both combat and noncombat situations from a variety of threats, including ballistic and blunt impact, acceleration, and blast. It is critical to understand the physics created by these threats to develop meaningful improvements to clinical care, injury prevention, and mitigation. Here the authors review the current state of understanding of the complex loading conditions that lead to TBI and characterize how these loads are transmitted through soft tissue, the skull and into the brain, resulting in TBI. In addition, gaps in knowledge and injury thresholds are reviewed, as these must be addressed to better design strategies that reduce TBI incidence and severity.

  10. MONETARY POLICY TRANSMISSION MECHANISM IN EMERGING COUNTRIES

    Directory of Open Access Journals (Sweden)

    Andreea ROŞOIU

    2013-06-01

    Full Text Available The transmission channels of monetary policy are used by central banks to accomplish the main objective of price stability in the context of sustainable economic growth. The importance of interest rate and exchange rate channels for the emerging countries Romania, Poland, Czech Republic and Hungary is analyzed by using Bayesian VAR approach with Diffuse priors over 1998Q1-2012Q3. Main result of the empirical study is that both channels are effective for the monetary policy transmission mechanism in Hungary and Czech Republic. In Romania and Poland they do not exhibit puzzles, but the impact of the macroeconomic variables is not very significant and shows very high volatility. In the context of monetary integration, exchange rate channel will become irrelevant when these countries adopt Euro currency. This change will lead instead to a powerful interest rate channel.

  11. Emergent Endotracheal Intubation and Mortality in Traumatic Brain Injury

    Directory of Open Access Journals (Sweden)

    Fine, Philip R

    2008-11-01

    Full Text Available Objective: To determine the relationship between emergent intubation (emergency department and field intubation cases combined and mortality in patients with traumatic brain injury (TBI while controlling for injury severity.Methods: Retrospective observational study of 981 (35.2% intubated, 64.8% not intubated patients with TBI evaluating the association between intubation status and mortality. Logistic regression was used to analyze the data. Injury severity measures included Head/Neck Abbreviated Injury Scale (H-AIS, systolic blood pressure, type of head injury (blunt vs. penetrating, and a propensity score combining the effects of several other potential confounding variables. Age was also included in the model.Results: The simple association of emergent endotracheal intubation with death had an odds ratio (OR of 14.3 (95% CI = 9.4 – 21.9. The logistic regression model including relevant covariates and a propensity score that adjusted for injury severity and age yielded an OR of 5.9 (95% CI = 3.2 – 10.9.Conclusions: This study indicates that emergent intubation is associated with increased risk of death after controlling for a number of injury severity indicators. We discuss the need for optimal paramedic training, and an understanding of the factors that guide patient selection and the decision to intubate in the field. [WestJEM.2008;9:184-189

  12. Developing Attention: Behavioral and Brain Mechanisms.

    Science.gov (United States)

    Posner, Michael I; Rothbart, Mary K; Sheese, Brad E; Voelker, Pascale

    2014-05-01

    Brain networks underlying attention are present even during infancy and are critical for the developing ability of children to control their emotions and thoughts. For adults, individual differences in the efficiency of attentional networks have been related to neuromodulators and to genetic variations. We have examined the development of attentional networks and child temperament in a longitudinal study from infancy (7 months) to middle childhood (7 years). Early temperamental differences among infants, including smiling and laughter and vocal reactivity, are related to self-regulation abilities at 7 years. However, genetic variations related to adult executive attention, while present in childhood, are poor predictors of later control, in part because individual genetic variationmay have many small effects and in part because their influence occurs in interaction with caregiver behavior and other environmental influences. While brain areas involved in attention are present during infancy, their connectivity changes and leads to improvement in control of behavior. It is also possible to influence control mechanisms through training later in life. The relation between maturation and learning may allow advances in our understanding of human brain development. PMID:25110757

  13. Developing Attention: Behavioral and Brain Mechanisms

    Directory of Open Access Journals (Sweden)

    Michael I. Posner

    2014-01-01

    Full Text Available Brain networks underlying attention are present even during infancy and are critical for the developing ability of children to control their emotions and thoughts. For adults, individual differences in the efficiency of attentional networks have been related to neuromodulators and to genetic variations. We have examined the development of attentional networks and child temperament in a longitudinal study from infancy (7 months to middle childhood (7 years. Early temperamental differences among infants, including smiling and laughter and vocal reactivity, are related to self-regulation abilities at 7 years. However, genetic variations related to adult executive attention, while present in childhood, are poor predictors of later control, in part because individual genetic variation may have many small effects and in part because their influence occurs in interaction with caregiver behavior and other environmental influences. While brain areas involved in attention are present during infancy, their connectivity changes and leads to improvement in control of behavior. It is also possible to influence control mechanisms through training later in life. The relation between maturation and learning may allow advances in our understanding of human brain development.

  14. Academic Emergency Medicine Physicians’ Knowledge of Mechanical Ventilation

    OpenAIRE

    Wilcox, Susan R.; Tania D. Strout; Jeffrey I. Schneider; Mitchell, Patricia M.; Smith, Jessica; Lutfy-Clayton, Lucienne; Marcolini, Evie G.; Aydin, Ani; Seigel, Todd A.; Jeremy B. Richards

    2016-01-01

    Introduction: Although emergency physicians frequently intubate patients, management of mechanical ventilation has not been emphasized in emergency medicine (EM) education or clinical practice. The objective of this study was to quantify EM attendings’ education, experience, and knowledge regarding mechanical ventilation in the emergency department. Methods: We developed a survey of academic EM attendings’ educational experiences with ventilators and a knowledge assessme...

  15. Academic Emergency Medicine Physicians’ Knowledge of Mechanical Ventilation

    OpenAIRE

    Wilcox, Susan R.; Tania D. Strout; Jeffrey I. Schneider; Mitchell, Patricia M.; Jessica Smith; Lucienne Lutfy-Clayton; Marcolini, Evie G.; Ani Aydin; Seigel, Todd A.; Jeremy B. Richards

    2016-01-01

    Introduction: Although emergency physicians frequently intubate patients, management of mechanical ventilation has not been emphasized in emergency medicine (EM) education or clinical practice. The objective of this study was to quantify EM attendings’ education, experience, and knowledge regarding mechanical ventilation in the emergency department. Methods: We developed a survey of academic EM attendings’ educational experiences with ventilators and a knowledge assessment tool with nine ...

  16. P300 brain computer interface: current challenges and emerging trends

    Directory of Open Access Journals (Sweden)

    Reza eFazel-Rezai

    2012-07-01

    Full Text Available A brain-computer interface (BCI enables communication without movement based on brain signals measured with electroencephalography (EEG. BCIs usually rely on one of three types of signals: the P300 and other components of the event-related potential (ERP, steady state visual evoked potential (SSVEP, or event related desynchronization (ERD. Although P300 BCIs were introduced over twenty years ago, the past few years have seen a strong increase in P300 BCI research. This closed-loop BCI approach relies on the P300 and other components of the event-related potential (ERP, based on an oddball paradigm presented to the subject. In this paper, we overview the current status of P300 BCI technology, and then discuss new directions: paradigms for eliciting P300s; signal processing methods; applications; and hybrid BCIs. We conclude that P300 BCIs are quite promising, as several emerging directions have not yet been fully explored and could lead to improvements in bit rate, reliability, usability, and flexibility.

  17. Inferring brain-computational mechanisms with models of activity measurements

    OpenAIRE

    Kriegeskorte, Nikolaus; Diedrichsen, Jörn

    2016-01-01

    High-resolution functional imaging is providing increasingly rich measurements of brain activity in animals and humans. A major challenge is to leverage such data to gain insight into the brain's computational mechanisms. The first step is to define candidate brain-computational models (BCMs) that can perform the behavioural task in question. We would then like to infer, which of the candidate BCMs best accounts for measured brain-activity data. Here we describe a method that complements each...

  18. Emerging roles for folate and related B-vitamins in brain health across the lifecycle.

    Science.gov (United States)

    McGarel, C; Pentieva, K; Strain, J J; McNulty, H

    2015-02-01

    Nutrition plays a fundamental role in supporting the structural and functional development of the human brain from conception, throughout early infancy and extending into later life. A growing body of evidence suggests that folate and the metabolically related B-vitamins are essential for brain health across all age groups, owing to their specific roles in C1 metabolism and particularly in the production of S-adenosylmethionine, a universal methyl donor essential for the production of neurotransmitters. Emerging, though not entirely consistent, evidence suggests that maternal folate status throughout pregnancy may influence neurodevelopment and behaviour of the offspring. Furthermore optimal B-vitamin status is associated with better cognitive health in ageing. Of note, a recent clinical trial provided evidence that supplementation with folic acid and related B-vitamins over a 2-year-period reduced global and regional brain atrophy, as measured by MRI scan in older adults. In terms of potential mechanisms, the effects of these B-vitamins on cognitive health may be independent or may be mediated by nutrient-nutrient and/or relevant gene-nutrient interactions. Furthermore, a new area of research suggests that the in utero environment influences health in later life. Folate, an important cofactor in C1 metabolism, is indirectly involved in DNA methylation, which in turn is considered to be one of the epigenetic mechanisms that may underlie fetal programming and brain development. The present review will explore the evidence that supports a role for folate and the related B-vitamins in brain health across the lifecycle, and potential mechanisms to explain such effects. PMID:25371067

  19. Mechanical properties of the brain-skull interface.

    Science.gov (United States)

    Mazumder, Mohammad Mynuddin Gani; Miller, Karol; Bunt, Stuart; Mostayed, Ahmed; Joldes, Grand; Day, Robert; Hart, Robin; Wittek, Adam

    2013-01-01

    Knowledge of the mechanical properties of the brain-skull interface is important for surgery simulation and injury biomechanics. These properties are known only to a limited extent. In this study we conducted in situ indentation of the sheep brain, and proposed to derive the macroscopic mechanical properties of the brain-skull interface from the results of these experiments. To the best of our knowledge, this is the first ever analysis of this kind. When conducting in situ indentation of the brain, the reaction force on the indentor was measured. After the indentation, a cylindrical sample of the brain tissue was extracted and subjected to uniaxial compression test. A model of the brain indentation experiment was built in the Finite Element (FE) solver ABAQUS™. In the model, the mechanical properties of the brain tissue were assigned as obtained from the uniaxial compression test and the brain-skull interface was modeled as linear springs. The interface stiffness (defined as sum of stiffnesses of the springs divided by the interface area) was varied to obtain good agreement between the calculated and experimentally measured indentor force-displacement relationship. Such agreement was found to occur for the brain-skull interface stiffness of 11.45 Nmm⁻¹/mm². This allowed identification of the overall mechanical properties of the brain-skull interface. PMID:23951996

  20. Emergence of classical theories from quantum mechanics

    CERN Document Server

    Hajicek, Petr

    2012-01-01

    Three problems stand in the way of deriving classical theories from quantum mechanics: those of realist interpretation, of classical properties and of quantum measurement. Recently, we have identified some tacit assumptions that lie at the roots of these problems. Thus, a realist interpretation is hindered by the assumption that the only properties of quantum systems are values of observables. If one simply postulates the properties to be objective that are uniquely defined by preparation then all difficulties disappear. As for classical properties, the wrong assumption is that there are arbitrarily sharp classical trajectories. It turns out that fuzzy classical trajectories can be obtained from quantum mechanics by taking the limit of high entropy. Finally, standard quantum mechanics implies that any registration on a quantum system is disturbed by all quantum systems of the same kind existing somewhere in the universe. If one works out systematically how quantum mechanics must be corrected so that there is ...

  1. Brain enabled mechanized speech synthesizer using Brain Mobile Interface

    Directory of Open Access Journals (Sweden)

    N.R.Raajan

    2013-02-01

    Full Text Available Communication is easily evoked when the necessity to carry out the thoughts and vision arises. As the communication technology developed it cultivated the threats of information security, on the otherhand physically challenged people have no possibility to communicate freely hence the urge for development in the field of communication is necessary in present scenario. Aim of this work is to propose a system that improves the present communication system. Here we had put forward the concept of Brain Mobile Interface (BMI from the basis of Brain Computer Interface (BCI. BMI serves as a device to translate human thoughts about speech without the need of physical movement. Wireless EEG headsets are used to acquire the speech signals directly from the brain and after signal processing it is given to the mobile which consist of inbuilt speller application. With the help of speller application the message to be conveyed is acquired as text which is then converted into speech by means of text to speech converter.

  2. Principals' Learning Mechanisms: Exploring an Emerging Construct

    Science.gov (United States)

    Schechter, Chen; Qadach, Mowafaq

    2016-01-01

    This exploration of principal learning mechanisms (PLM) to support a learning-centered school aimed to develop, field-test, and validate a PLM-measuring instrument. Following exploratory and confirmatory factor analyses of items to examine factorial validity, the developed scale was correlated with other work-related established constructs (e.g.,…

  3. Operational Mechanism and Evaluation System for Emergency Logistics Risks

    OpenAIRE

    Qi Cheng; Lei Yu

    2010-01-01

    Lots of risks existed in the operating process of emergency logistics especially when natural disasters happened. Both operating mechanism and evaluation system research on Emergency Logistics Risks (ELR) are the basis of effective recognizing, preventing and responding to risks, so it’s of great theoretical and practical significance to study the formation and influence mechanism and to establish an evaluating index system for ELR. Firstly, some foundation research about ELR was carried out,...

  4. Emergence Of Consciousness And Qualia From A Complex Brain

    Directory of Open Access Journals (Sweden)

    Korf Jakob

    2014-12-01

    Full Text Available Qualia are private conscious experiences of which the associated feelings can be reported to other people. Whether qualia are amenable to scientific exploration has often been questioned, which is challenged by the present article. The following arguments are given: 1. the configuration of the brain changes continuously and irreversibly, because of genetic and environmental influences and interhuman communication; 2. qualia and consciousness are processes, rather than states; 3. private feelings, including those associated with qualia, should be positioned in the context of a personal brain as being developed during life; 4. consciousness and qualia should be understood in the context of general system theory, thus concluding that isolated, in vitro, properties of neurons and other brain constituents might marginally contribute to the understanding of higher brain functions, mind or qualia; 5. current in vivo approaches have too little resolution power - in terms of space and time - to delineate individual and subjective brain processes.

  5. Towards the Self-constructive Brain: emergence of adaptive behavior

    OpenAIRE

    Corbacho, Fernando

    2016-01-01

    Adaptive behavior is mainly the result of adaptive brains. We go a step beyond and claim that the brain does not only adapt to its surrounding reality but rather, it builds itself up to constructs its own reality. That is, rather than just trying to passively understand its environment, the brain is the architect of its own reality in an active process where its internal models of the external world frame how its new interactions with the environment are assimilated. These internal models rep...

  6. Brain-to-Brain coupling: A mechanism for creating and sharing a social world

    OpenAIRE

    Hasson, Uri; Asif A Ghazanfar; GALANTUCCI, BRUNO; Garrod, Simon; Keysers, Christian

    2012-01-01

    Cognition materializes in an interpersonal space. The emergence of complex behaviors requires the coordination of actions among individuals according to a shared set of rules. Despite the central role of other individuals in shaping our minds, most cognitive studies focus on processes that occur within a single individual. We call for a shift from a single-brain to a multi-brain frame of reference. We argue that in many cases the neural processes in one brain are coupled to the neural process...

  7. Pathophysiologic mechanisms of brain-body associations in ruptured brain aneurysms: A systematic review

    Directory of Open Access Journals (Sweden)

    Benjamin W. Y. Lo

    2015-01-01

    Conclusions: This systematic review synthesizes the most current evidence of underlying mechanisms of brain related associations with body systems in aneurysmal subarachnoid hemorrhage. Results gained from these studies are clinically useful and shed light on how ruptured brain aneurysms affect the cardiopulmonary system. Subsequent neuro-cardio-endocrine responses then interact with other body systems as part of the secondary responses to primary injury.

  8. Vocal emotion of humanoid robots: a study from brain mechanism.

    Science.gov (United States)

    Wang, Youhui; Hu, Xiaohua; Dai, Weihui; Zhou, Jie; Kuo, Taitzong

    2014-01-01

    Driven by rapid ongoing advances in humanoid robot, increasing attention has been shifted into the issue of emotion intelligence of AI robots to facilitate the communication between man-machines and human beings, especially for the vocal emotion in interactive system of future humanoid robots. This paper explored the brain mechanism of vocal emotion by studying previous researches and developed an experiment to observe the brain response by fMRI, to analyze vocal emotion of human beings. Findings in this paper provided a new approach to design and evaluate the vocal emotion of humanoid robots based on brain mechanism of human beings. PMID:24587712

  9. Developing Attention: Behavioral and Brain Mechanisms

    OpenAIRE

    Posner, Michael I.; Rothbart, Mary K.; Sheese, Brad E.; Pascale Voelker

    2014-01-01

    Brain networks underlying attention are present even during infancy and are critical for the developing ability of children to control their emotions and thoughts. For adults, individual differences in the efficiency of attentional networks have been related to neuromodulators and to genetic variations. We have examined the development of attentional networks and child temperament in a longitudinal study from infancy (7 months) to middle childhood (7 years). Early temperamental differences am...

  10. Emergence Of Consciousness And Qualia From A Complex Brain.

    Science.gov (United States)

    Korf, Jakob

    2014-01-01

    Qualia are private conscious experiences of which the associated feelings can be reported to other people. Whether qualia are amenable to scientific exploration has often been questioned, which is challenged by the present article. The following arguments are given: 1. the configuration of the brain changes continuously and irreversibly, because of genetic and environmental influences and interhuman communication; 2. qualia and consciousness are processes, rather than states; 3. private feelings, including those associated with qualia, should be positioned in the context of a personal brain as being developed during life; 4. consciousness and qualia should be understood in the context of general system theory, thus concluding that isolated, in vitro, properties of neurons and other brain constituents might marginally contribute to the understanding of higher brain functions, mind or qualia; 5. current in vivo approaches have too little resolution power - in terms of space and time - to delineate individual and subjective brain processes. When subtle personalized properties of the nervous system can be assessed in vivo or in vitro, qualia can scientifically be investigated. We discuss some approaches to overcome these barriers. PMID:26444360

  11. Blood-brain barrier permeability and brain uptake mechanism of kainic Acid and dihydrokainic Acid

    DEFF Research Database (Denmark)

    Gynther, Mikko; Petsalo, Aleksanteri; Hansen, Steen Honoré;

    2015-01-01

    is low, 0.25 × 10(-6) and 0.28 × 10(-6) cm/s for KA and DHK, respectively. In addition, the brain uptake is mediated by passive diffusion, and not by active transport. Furthermore, the non-specific plasma and brain protein binding of KA and DHK was determined to be low, which means that the unbound drug...... tools in various in vivo central nervous system disease models in rodents, as well as being templates in the design of novel ligands affecting the glutamatergic system. Both molecules are highly polar but yet capable of crossing the blood-brain barrier (BBB). We used an in situ rat brain perfusion...... technique to determine the brain uptake mechanism and permeability across the BBB. To determine KA and DHK concentrations in the rat brain, simple and rapid sample preparation and liquid chromatography mass spectrometer methods were developed. According to our results the BBB permeability of KA and DHK...

  12. Barrier mechanisms in the Drosophila blood-brain barrier

    Directory of Open Access Journals (Sweden)

    Samantha Jane Hindle

    2014-12-01

    Full Text Available The invertebrate blood-brain barrier field is growing at a rapid pace and, in recent years, studies have shown a physiologic and molecular complexity that has begun to rival its vertebrate counterpart. Novel mechanisms of paracellular barrier maintenance through GPCR signaling were the first demonstrations of the complex adaptive mechanisms of barrier physiology. Building upon this work, the integrity of the invertebrate blood-brain barrier has recently been shown to require coordinated function of all layers of the compound barrier structure, analogous to signaling between the layers of the vertebrate neurovascular unit. These findings strengthen the notion that many blood-brain barrier mechanisms are conserved between vertebrates and invertebrates, and suggest that novel findings in invertebrate model organisms will have a significant impact on the understanding of vertebrate BBB functions. In this vein, important roles in coordinating localized and systemic signaling to dictate organism development and growth are beginning to show how the blood-brain barrier can govern whole animal physiologies. This includes novel functions of blood-brain barrier gap junctions in orchestrating synchronized neuroblast proliferation, and of blood-brain barrier secreted antagonists of insulin receptor signaling. These advancements and others are pushing the field forward in exciting new directions. In this review, we provide a synopsis of invertebrate blood-brain barrier anatomy and physiology, with a focus on insights from the past 5 years, and highlight important areas for future study.

  13. Academic Emergency Medicine Physicians’ Knowledge of Mechanical Ventilation

    Directory of Open Access Journals (Sweden)

    Susan R. Wilcox

    2016-05-01

    Full Text Available Introduction: Although emergency physicians frequently intubate patients, management of mechanical ventilation has not been emphasized in emergency medicine (EM education or clinical practice. The objective of this study was to quantify EM attendings’ education, experience, and knowledge regarding mechanical ventilation in the emergency department. Methods: We developed a survey of academic EM attendings’ educational experiences with ventilators and a knowledge assessment tool with nine clinical questions. EM attendings at key teaching hospitals for seven EM residency training programs in the northeastern United States were invited to participate in this survey study. We performed correlation and regression analyses to evaluate the relationship between attendings’ scores on the assessment instrument and their training, education, and comfort with ventilation. Results: Of 394 EM attendings surveyed, 211 responded (53.6%. Of respondents, 74.5% reported receiving three or fewer hours of ventilation-related education from EM sources over the past year and 98 (46% reported receiving between 0-1 hour of education. The overall correct response rate for the assessment tool was 73.4%, with a standard deviation of 19.9. The factors associated with a higher score were completion of an EM residency, prior emphasis on mechanical ventilation during one’s own residency, working in a setting where an emergency physician bears primary responsibility for ventilator management, and level of comfort with managing ventilated patients. Physicians’ comfort was associated with the frequency of ventilator changes and EM management of ventilation, as well as hours of education. Conclusion: EM attendings report caring for mechanically ventilated patients frequently, but most receive fewer than three educational hours a year on mechanical ventilation, and nearly half receive 0-1 hour. Physicians’ performance on an assessment tool for mechanical ventilation is

  14. Mechanism of Chronic Pain in Rodent Brain Imaging

    Science.gov (United States)

    Chang, Pei-Ching

    Chronic pain is a significant health problem that greatly impacts the quality of life of individuals and imparts high costs to society. Despite intense research effort in understanding of the mechanism of pain, chronic pain remains a clinical problem that has few effective therapies. The advent of human brain imaging research in recent years has changed the way that chronic pain is viewed. To further extend the use of human brain imaging techniques for better therapies, the adoption of imaging technique onto the animal pain models is essential, in which underlying brain mechanisms can be systematically studied using various combination of imaging and invasive techniques. The general goal of this thesis is to addresses how brain develops and maintains chronic pain in an animal model using fMRI. We demonstrate that nucleus accumbens, the central component of mesolimbic circuitry, is essential in development of chronic pain. To advance our imaging technique, we develop an innovative methodology to carry out fMRI in awake, conscious rat. Using this cutting-edge technique, we show that allodynia is assoicated with shift brain response toward neural circuits associated nucleus accumbens and prefrontal cortex that regulate affective and cognitive component of pain. Taken together, this thesis provides a deeper understanding of how brain mediates pain. It builds on the existing body of knowledge through maximizing the depth of insight into brain imaging of chronic pain.

  15. Development of brain mechanisms for processing affective touch

    OpenAIRE

    Malin eBjornsdotter; Ilanit eGordon; Pelphrey, Kevin A.; Håkan eOlausson; Martha eKaiser

    2014-01-01

    Affective tactile stimulation plays a key role in the maturation of neural circuits, but the development of brain mechanisms processing touch is poorly understood. We therefore used functional magnetic resonance imaging (fMRI) to study brain responses to soft brush stroking of both glabrous (palm) and hairy (forearm) skin in healthy children (5-13 years), adolescents (14-17 years), and adults (25-35 years). Adult-defined regions-of-interests in the primary somatosensory cortex (SI), secondary...

  16. Blood-brain barrier permeability and brain uptake mechanism of kainic acid and dihydrokainic acid.

    Science.gov (United States)

    Gynther, Mikko; Petsalo, Aleksanteri; Hansen, Steen H; Bunch, Lennart; Pickering, Darryl S

    2015-03-01

    The glutamatergic neurotransmitter system is involved in important neurophysiological processes and thus constitutes a promising target for the treatment of neurological diseases. The two ionotropic glutamate receptor agonists kainic acid (KA) and dihydrokainic acid (DHK) have been used as research tools in various in vivo central nervous system disease models in rodents, as well as being templates in the design of novel ligands affecting the glutamatergic system. Both molecules are highly polar but yet capable of crossing the blood-brain barrier (BBB). We used an in situ rat brain perfusion technique to determine the brain uptake mechanism and permeability across the BBB. To determine KA and DHK concentrations in the rat brain, simple and rapid sample preparation and liquid chromatography mass spectrometer methods were developed. According to our results the BBB permeability of KA and DHK is low, 0.25 × 10(-6) and 0.28 × 10(-6) cm/s for KA and DHK, respectively. In addition, the brain uptake is mediated by passive diffusion, and not by active transport. Furthermore, the non-specific plasma and brain protein binding of KA and DHK was determined to be low, which means that the unbound drug volume of distribution in brain is also low. Therefore, even though the total KA and DHK concentrations in the brain are low after systemic dosing, the concentrations in the vicinity of the glutamate receptors are sufficient for their activation and thus the observed efficacy.

  17. Speculations on the emergence of self-awareness in big-brained organisms

    OpenAIRE

    Tannenbaum, Emmanuel

    2007-01-01

    This paper argues that self-awareness is a learned behavior that emerges in organisms whose brains have a sufficiently integrated, complex ability for associative learning and memory. Continual sensory input of information related to the organism causes the organism's brain to learn the physical characteristics of the organism, in the sense that neural pathways are produced that are reinforced by, and therefore recognize, various features associated with the organism. This results in the form...

  18. On the Ricci flow and emergent quantum mechanics

    CERN Document Server

    Isidro, J M; de Cordoba, P Fernandez

    2009-01-01

    The Ricci flow equation of a conformally flat Riemannian metric on a closed 2-dimensional configuration space is analysed. It turns out to be equivalent to the classical Hamilton-Jacobi equation for a point particle subject to a potential function that is proportional to the Ricci scalar curvature of configuration space. This allows one to obtain Schroedinger quantum mechanics from Perelman's action functional: the quantum-mechanical wavefunction is the exponential of $i$ times the conformal factor of the metric on configuration space. We explore links with the recently discussed emergent quantum mechanics.

  19. Bohmian mechanics, collapse models and the emergence of classicality

    Science.gov (United States)

    Toroš, Marko; Donadi, Sandro; Bassi, Angelo

    2016-09-01

    We discuss the emergence of classical trajectories in Bohmian mechanics, when a macroscopic object interacts with an external environment. We show that in such a case the conditional wave function of the system follows a dynamics which, under reasonable assumptions, corresponds to that of the Ghirardi-Rimini-Weber (GRW) collapse model. As a consequence, Bohmian trajectories evolve classically. Our analysis also shows how the GRW (istantaneous) collapse process can be derived by an underlying continuous interaction of a quantum system with an external agent, thus throwing a light on how collapses can emerge from a deeper level theory.

  20. Brain alterations and clinical symptoms of dementia in diabetes: Abeta/tau-dependent and independent mechanisms

    Directory of Open Access Journals (Sweden)

    Naoyuki eSato

    2014-09-01

    Full Text Available Emerging evidence suggests that diabetes affects cognitive function and increases the incidence of dementia. However, the mechanisms by which diabetes modifies cognitive function still remains unclear. Morphologically, diabetes is associated with neuronal loss in the frontal and temporal lobes including the hippocampus, and aberrant functional connectivity of the posterior cingulate cortex and medial frontal/temporal gyrus. Clinically, diabetic patients show decreased executive function, information processing, planning, visuospatial construction, and visual memory. Therefore, in comparison with the characteristics of AD brain structure and cognition, diabetes seems to affect cognitive function through not only simple AD pathological feature-dependent mechanisms, but also independent mechanisms. As an Abeta/tau-independent mechanism, diabetes compromises cerebrovascular function, increases subcortical infarction and might alter the blood brain barrier (BBB. Diabetes also affects glucose metabolism, insulin signaling and mitochondrial function in the brain. Diabetes also modifies metabolism of Abeta and tau and causes Abeta/tau-dependent pathological changes. Moreover, there is evidence that suggests an interaction between Abeta/tau-dependent and independent mechanisms. Therefore, diabetes modifies cognitive function through Abeta/tau-dependent and independent mechanisms. Interaction between these two mechanisms forms a vicious cycle.

  1. PHILOSOPHY OF MIND; THEORETICAL AND EXPERIMENTAL CONTRIBUTION TO THE EMERGING VISION OF MIND-BRAIN INTERACTION.

    Directory of Open Access Journals (Sweden)

    Paul Ruiz Santos

    2011-12-01

    Full Text Available This work aims to contribute to the discussion of mind-brain interactions from an emergentism point of view of the Philosophy of Mind, using some of the naturalized theories. Some proposed bridges between mind and brain based on experimental naturalization are neuro-psychoanalysis, mirror neurons, and psychosomatics, among others. Naturalization can be achieved by earching for the link between psychological and biological processes. This biological-based approach can be developed avoiding mplification and reductionism of psychological processes. We discuss the access to new insights about the mind-brain relationship and its implications through neurophenomenology, from an emerging and interactionist point of view.

  2. The emerging quantum the physics behind quantum mechanics

    CERN Document Server

    Pena, Luis de la; Valdes-Hernandez, Andrea

    2014-01-01

    This monograph presents the latest findings from a long-term research project intended to identify the physics behind Quantum Mechanics. A fundamental theory for quantum mechanics is constructed from first physical principles, revealing quantization as an emergent phenomenon arising from a deeper stochastic process. As such, it offers the vibrant community working on the foundations of quantum mechanics an alternative contribution open to discussion. The book starts with a critical summary of the main conceptual problems that still beset quantum mechanics.  The basic consideration is then introduced that any material system is an open system in permanent contact with the random zero-point radiation field, with which it may reach a state of equilibrium. Working from this basis, a comprehensive and self-consistent theoretical framework is then developed. The pillars of the quantum-mechanical formalism are derived, as well as the radiative corrections of nonrelativistic QED, while revealing the underlying physi...

  3. Quantum mechanics emerging from stochastic dynamics of virtual particles

    CERN Document Server

    Tsekov, R

    2015-01-01

    It is demonstrated how quantum mechanics emerges from the stochastic dynamics of force-carriers. It is shown that the quantum Moyal equation corresponds to some dynamic correlations between the momentum of a real particle and the position of a virtual particle, which are not present in classical mechanics. The new concept throws light on the physical meaning of quantum theory, showing that the Planck constant square is a second-second cross-cumulant. The novel approach to quantum systems is extended to the relativistic case and an expression is derived for the relativistic mass in the Wigner quantum phase-space.

  4. Blood-brain barrier shuttle peptides: an emerging paradigm for brain delivery.

    Science.gov (United States)

    Oller-Salvia, Benjamí; Sánchez-Navarro, Macarena; Giralt, Ernest; Teixidó, Meritxell

    2016-08-22

    Brain delivery is one of the major challenges in drug development because of the high number of patients suffering from neural diseases and the low efficiency of the treatments available. Although the blood-brain barrier (BBB) prevents most drugs from reaching their targets, molecular vectors - known as BBB shuttles - offer great promise to safely overcome this formidable obstacle. In recent years, peptide shuttles have received growing attention because of their lower cost, reduced immunogenicity, and higher chemical versatility than traditional Trojan horse antibodies and other proteins. PMID:27188322

  5. Emerging Molecular Targets for Brain Repair after Stroke

    Directory of Open Access Journals (Sweden)

    Jerzy Krupinski

    2013-01-01

    Full Text Available The field of neuroprotection generated consistent preclinical findings of mechanisms of cell death but these failed to be translated into clinics. The approaches that combine the modulation of the inhibitory environment together with the promotion of intrinsic axonal outgrowth needs further work before combined therapeutic strategies will be transferable to clinic trials. It is likely that only when some answers have been found to these issues will our therapeutic efforts meet our expectations. Stroke is a clinically heterogeneous disease and combinatorial treatments require much greater work in pharmacological and toxicological testing. Advances in genetics and results of the Whole Human Genome Project (HGP provided new unknown information in relation to stroke. Genetic factors are not the only determinants of responses to some diseases. It was recognized early on that “epigenetic” factors were major players in the aetiology and progression of many diseases like stroke. The major players are microRNAs that represent the best-characterized subclass of noncoding RNAs. Epigenetic mechanisms convert environmental conditions and physiological stresses into long-term changes in gene expression and translation. Epigenetics in stroke are in their infancy but offer great promise for better understanding of stroke pathology and the potential viability of new strategies for its treatment.

  6. Emerging Molecular Targets for Brain Repair after Stroke

    Science.gov (United States)

    Krupinski, Jerzy; Slevin, Mark

    2013-01-01

    The field of neuroprotection generated consistent preclinical findings of mechanisms of cell death but these failed to be translated into clinics. The approaches that combine the modulation of the inhibitory environment together with the promotion of intrinsic axonal outgrowth needs further work before combined therapeutic strategies will be transferable to clinic trials. It is likely that only when some answers have been found to these issues will our therapeutic efforts meet our expectations. Stroke is a clinically heterogeneous disease and combinatorial treatments require much greater work in pharmacological and toxicological testing. Advances in genetics and results of the Whole Human Genome Project (HGP) provided new unknown information in relation to stroke. Genetic factors are not the only determinants of responses to some diseases. It was recognized early on that “epigenetic” factors were major players in the aetiology and progression of many diseases like stroke. The major players are microRNAs that represent the best-characterized subclass of noncoding RNAs. Epigenetic mechanisms convert environmental conditions and physiological stresses into long-term changes in gene expression and translation. Epigenetics in stroke are in their infancy but offer great promise for better understanding of stroke pathology and the potential viability of new strategies for its treatment. PMID:23365789

  7. Operational Mechanism and Evaluation System for Emergency Logistics Risks

    Directory of Open Access Journals (Sweden)

    Qi Cheng

    2010-12-01

    Full Text Available Lots of risks existed in the operating process of emergency logistics especially when natural disasters happened. Both operating mechanism and evaluation system research on Emergency Logistics Risks (ELR are the basis of effective recognizing, preventing and responding to risks, so it’s of great theoretical and practical significance to study the formation and influence mechanism and to establish an evaluating index system for ELR. Firstly, some foundation research about ELR was carried out, including definition, characteristics and classification of ELR. The formation and influence mechanism of ELR were discussed. The research of questionnaire survey offered an objective support for theoretical mechanism and index system establishment. Then, the evaluating index system for ELR was established. This system was a multi-level index system, and mainly evaluated by the decision-making risk, dispatching and commanding risk, organizing and coordinating risk, executing and controlling risk, resources supporting risk and their sub index. The establishment principles and significance of the index system were discussed. Then, the fuzzy comprehensive evaluation and Delphi method were used to confirm the index weight and value. Finally, a case analysis on ELR of Yushu earthquake was conducted to demonstrate the evaluating index system and to evaluate the actual risk level.

  8. Mechanical ventilation in emergency departments: Non invasive or invasive mechanical ventilation. Where is the answer?

    OpenAIRE

    Esquinas Rodriguez Antonio M; Cosentini Roberto; Papadakos Peter J

    2012-01-01

    The Emergency Department length of stay for patients requiring mechanical ventilation paper in this issue is very illustrative of many variables that still confound the way we treat patients that may not require endotracheal intubation (ETI) but may benefit from non-invasive mechanical ventilation (NIV) [1].

  9. Iodine Deficiency and the Brain: Effects and Mechanisms.

    Science.gov (United States)

    Redman, Kahla; Ruffman, Ted; Fitzgerald, Penelope; Skeaff, Sheila

    2016-12-01

    Iodine is an essential micronutrient needed in human diets. As iodine is an integral component of thyroid hormone, it mediates the effects of thyroid hormone on brain development. Iodine deficiency is the most prevalent and preventable cause of mental impairment in the world. The exact mechanism through which iodine influences the brain is unclear, but is generally thought to begin with genetic expression. Many brain structures and systems appear to be affected with iodine deficiency, including areas such as the hippocampus, microstructures such as myelin, and neurotransmitters. The clearest evidence comes from the studies examining cognition in the cases of iodine deprivation or interventions involving iodine supplementation. Nevertheless, there are many inconsistencies and gaps in the literature of iodine deficiency, especially over the lifespan. This paper summarizes the literature on this topic, suggests a causal mechanism for iodine's effect on the brain, and indicates areas for the future research (e.g., using magnetic resonance imaging (MRI) and functional MRI to examine how iodine supplementation facilitates cognitive functioning). PMID:25880137

  10. Development of brain mechanisms for processing affective touch

    Directory of Open Access Journals (Sweden)

    Malin eBjornsdotter

    2014-02-01

    Full Text Available Affective tactile stimulation plays a key role in the maturation of neural circuits, but the development of brain mechanisms processing touch is poorly understood. We therefore used functional magnetic resonance imaging (fMRI to study brain responses to soft brush stroking of both glabrous (palm and hairy (forearm skin in healthy children (5-13 years, adolescents (14-17 years and adults (25-35 years. Adult-defined regions-of-interests in the primary somatosensory cortex (SI, secondary somatosensory cortex (SII, insular cortex and right posterior superior temporal sulcus (pSTS were significantly and similarly activated in all age groups. Whole-brain analyses revealed that responses in the ipsilateral SII were positively correlated with age in both genders, and that responses in bilateral regions near the pSTS correlated significantly and strongly with age in females but not in males. These results suggest that brain mechanisms associated with both sensory-discriminative and affective-motivational aspects of touch are largely established in school-aged children, and that there is a general continuing maturation of SII and a female-specific increase in pSTS sensitivity with age. Our work establishes a groundwork for future comparative studies of tactile processing in developmental disorders characterized by disrupted social perception such as autism.

  11. Adenosine, ketogenic diet and epilepsy: the emerging therapeutic relationship between metabolism and brain activity.

    Science.gov (United States)

    Masino, S A; Kawamura, M; Wasser, C D; Wasser, C A; Pomeroy, L T; Ruskin, D N

    2009-09-01

    For many years the neuromodulator adenosine has been recognized as an endogenous anticonvulsant molecule and termed a "retaliatory metabolite." As the core molecule of ATP, adenosine forms a unique link between cell energy and neuronal excitability. In parallel, a ketogenic (high-fat, low-carbohydrate) diet is a metabolic therapy that influences neuronal activity significantly, and ketogenic diets have been used successfully to treat medically-refractory epilepsy, particularly in children, for decades. To date the key neural mechanisms underlying the success of dietary therapy are unclear, hindering development of analogous pharmacological solutions. Similarly, adenosine receptor-based therapies for epilepsy and myriad other disorders remain elusive. In this review we explore the physiological regulation of adenosine as an anticonvulsant strategy and suggest a critical role for adenosine in the success of ketogenic diet therapy for epilepsy. While the current focus is on the regulation of adenosine, ketogenic metabolism and epilepsy, the therapeutic implications extend to acute and chronic neurological disorders as diverse as brain injury, inflammatory and neuropathic pain, autism and hyperdopaminergic disorders. Emerging evidence for broad clinical relevance of the metabolic regulation of adenosine will be discussed. PMID:20190967

  12. Inhibitory Antibodies Targeting Emerging Viruses: Advancements and Mechanisms.

    Science.gov (United States)

    Jin, Jing; Simmons, Graham

    2016-07-01

    From Ebola virus outbreaks in Western Africa to the introduction of chikungunya and Zika viruses in the Americas, new and neglected viruses continue to emerge and spread around the world. Due to a lack of existing vaccines or specific therapeutics, little other than supportive care and attempts to interrupt transmission can be provided during initial outbreaks. This has prompted a shift in vaccine design and development to identify novel epitopes and mechanisms of protection that may offer a broader range of protection against groups or whole families of viruses. Receptor-binding domains and other motifs within viral envelope proteins represent one excellent opportunity to target communal epitopes shared by related viruses. Similarly, for viruses where envelope participates in driving viral egress from infected cells, shared epitopes need to be identified to guide the development of broadly protective antibodies and vaccines. Here, we discuss recent advances in our understanding of broadly protective humoral responses for emerging viruses. PMID:27226280

  13. Quantum Mechanics, Pattern Recognition, and the Mammalian Brain

    Science.gov (United States)

    Chapline, George

    2008-10-01

    Although the usual way of representing Markov processes is time asymmetric, there is a way of describing Markov processes, due to Schrodinger, which is time symmetric. This observation provides a link between quantum mechanics and the layered Bayesian networks that are often used in automated pattern recognition systems. In particular, there is a striking formal similarity between quantum mechanics and a particular type of Bayesian network, the Helmholtz machine, which provides a plausible model for how the mammalian brain recognizes important environmental situations. One interesting aspect of this relationship is that the "wake-sleep" algorithm for training a Helmholtz machine is very similar to the problem of finding the potential for the multi-channel Schrodinger equation. As a practical application of this insight it may be possible to use inverse scattering techniques to study the relationship between human brain wave patterns, pattern recognition, and learning. We also comment on whether there is a relationship between quantum measurements and consciousness.

  14. Emergent patterns of growth controlled by multicellular form and mechanics

    Science.gov (United States)

    Nelson, Celeste M.; Jean, Ronald P.; Tan, John L.; Liu, Wendy F.; Sniadecki, Nathan J.; Spector, Alexander A.; Chen, Christopher S.

    2005-01-01

    Spatial patterns of cellular growth generate mechanical stresses that help to push, fold, expand, and deform tissues into their specific forms. Genetic factors are thought to specify patterns of growth and other behaviors to drive morphogenesis. Here, we show that tissue form itself can feed back to regulate patterns of proliferation. Using microfabrication to control the organization of sheets of cells, we demonstrated the emergence of stable patterns of proliferative foci. Regions of concentrated growth corresponded to regions of high tractional stress generated within the sheet, as predicted by a finite-element model of multicellular mechanics and measured directly by using a micromechanical force sensor array. Inhibiting actomyosin-based tension or cadherin-mediated connections between cells disrupted the spatial pattern of proliferation. These findings demonstrate the existence of patterns of mechanical forces that originate from the contraction of cells, emerge from their multicellular organization, and result in patterns of growth. Thus, tissue form is not only a consequence but also an active regulator of tissue growth. PMID:16049098

  15. Brain Mechanisms of Altered Consciousness in Generalised Seizures

    Directory of Open Access Journals (Sweden)

    Stefano Seri

    2011-01-01

    Full Text Available In spite of the inherent difficulties in achieving a biologically meaningful definition of consciousness, recent neurophysiological studies are starting to provide some insight in fundamental mechanisms associated with impaired consciousness in neurological disorders. Generalised seizures are associated with disruption of the default state network, a functional network of discrete brain areas, which include the fronto-parietal cortices. Subcortical contribution through activation of thalamocortical structures, as well as striate nuclei are also crucial to produce impaired consciousness in generalised seizures.

  16. Brain. Conscious and unconscious mechanisms of cognition, emotions, and language.

    Science.gov (United States)

    Perlovsky, Leonid; Ilin, Roman

    2012-01-01

    Conscious and unconscious brain mechanisms, including cognition, emotions and language are considered in this review. The fundamental mechanisms of cognition include interactions between bottom-up and top-down signals. The modeling of these interactions since the 1960s is briefly reviewed, analyzing the ubiquitous difficulty: incomputable combinatorial complexity (CC). Fundamental reasons for CC are related to the Gödel's difficulties of logic, a most fundamental mathematical result of the 20th century. Many scientists still "believed" in logic because, as the review discusses, logic is related to consciousness; non-logical processes in the brain are unconscious. CC difficulty is overcome in the brain by processes "from vague-unconscious to crisp-conscious" (representations, plans, models, concepts). These processes are modeled by dynamic logic, evolving from vague and unconscious representations toward crisp and conscious thoughts. We discuss experimental proofs and relate dynamic logic to simulators of the perceptual symbol system. "From vague to crisp" explains interactions between cognition and language. Language is mostly conscious, whereas cognition is only rarely so; this clarifies much about the mind that might seem mysterious. All of the above involve emotions of a special kind, aesthetic emotions related to knowledge and to cognitive dissonances. Cognition-language-emotional mechanisms operate throughout the hierarchy of the mind and create all higher mental abilities. The review discusses cognitive functions of the beautiful, sublime, music. PMID:24961270

  17. Crash Simulator: Brain-and-Spine Injury Mechanics

    Science.gov (United States)

    Ivancevic, Vladimir G.; Reid, Darryn J.

    2015-11-01

    Recently, the first author has proposed a new coupled loading-rate hypothesis as a unique cause of both brain and spinal injuries, which states that they are both caused by a Euclidean jolt, an impulsive loading that strikes head and spine (or, any other part of the human body)- in several coupled degrees-of-freedom simultaneously. Injury never happens in a single direction only, nor is it ever caused by a static force. It is always an impulsive translational plus rotational force. The Euclidean jolt causes two basic forms of brain, spine and other musculo-skeletal injuries: (i) localized translational dislocations; and (ii) localized rotational disclinations. In the present Chapter, we first review this unique mechanics of a general human mechanical injury, and then describe how it can be predicted and controlled by a crash simulator toolbox. This rigorous Matlab toolbox has been developed using an existing thirdparty toolbox DiffMan, for accurately solving differential equations on smooth manifolds and mechanical Lie groups. The present crash simulator toolbox performs prediction/control of brain and spinal injuries within the framework of the Euclidean group SE(3) of rigid motions in our natural 3-dimensional space.

  18. Brain. Conscious and Unconscious Mechanisms of Cognition, Emotions, and Language

    Directory of Open Access Journals (Sweden)

    Roman Ilin

    2012-12-01

    Full Text Available Conscious and unconscious brain mechanisms, including cognition, emotions and language are considered in this review. The fundamental mechanisms of cognition include interactions between bottom-up and top-down signals. The modeling of these interactions since the 1960s is briefly reviewed, analyzing the ubiquitous difficulty: incomputable combinatorial complexity (CC. Fundamental reasons for CC are related to the Gödel’s difficulties of logic, a most fundamental mathematical result of the 20th century. Many scientists still “believed” in logic because, as the review discusses, logic is related to consciousness; non-logical processes in the brain are unconscious. CC difficulty is overcome in the brain by processes “from vague-unconscious to crisp-conscious” (representations, plans, models, concepts. These processes are modeled by dynamic logic, evolving from vague and unconscious representations toward crisp and conscious thoughts. We discuss experimental proofs and relate dynamic logic to simulators of the perceptual symbol system. “From vague to crisp” explains interactions between cognition and language. Language is mostly conscious, whereas cognition is only rarely so; this clarifies much about the mind that might seem mysterious. All of the above involve emotions of a special kind, aesthetic emotions related to knowledge and to cognitive dissonances. Cognition-language-emotional mechanisms operate throughout the hierarchy of the mind and create all higher mental abilities. The review discusses cognitive functions of the beautiful, sublime, music.

  19. Inferring brain-computational mechanisms with models of activity measurements.

    Science.gov (United States)

    Kriegeskorte, Nikolaus; Diedrichsen, Jörn

    2016-10-01

    High-resolution functional imaging is providing increasingly rich measurements of brain activity in animals and humans. A major challenge is to leverage such data to gain insight into the brain's computational mechanisms. The first step is to define candidate brain-computational models (BCMs) that can perform the behavioural task in question. We would then like to infer which of the candidate BCMs best accounts for measured brain-activity data. Here we describe a method that complements each BCM by a measurement model (MM), which simulates the way the brain-activity measurements reflect neuronal activity (e.g. local averaging in functional magnetic resonance imaging (fMRI) voxels or sparse sampling in array recordings). The resulting generative model (BCM-MM) produces simulated measurements. To avoid having to fit the MM to predict each individual measurement channel of the brain-activity data, we compare the measured and predicted data at the level of summary statistics. We describe a novel particular implementation of this approach, called probabilistic representational similarity analysis (pRSA) with MMs, which uses representational dissimilarity matrices (RDMs) as the summary statistics. We validate this method by simulations of fMRI measurements (locally averaging voxels) based on a deep convolutional neural network for visual object recognition. Results indicate that the way the measurements sample the activity patterns strongly affects the apparent representational dissimilarities. However, modelling of the measurement process can account for these effects, and different BCMs remain distinguishable even under substantial noise. The pRSA method enables us to perform Bayesian inference on the set of BCMs and to recognize the data-generating model in each case.This article is part of the themed issue 'Interpreting BOLD: a dialogue between cognitive and cellular neuroscience'.

  20. Inferring brain-computational mechanisms with models of activity measurements.

    Science.gov (United States)

    Kriegeskorte, Nikolaus; Diedrichsen, Jörn

    2016-10-01

    High-resolution functional imaging is providing increasingly rich measurements of brain activity in animals and humans. A major challenge is to leverage such data to gain insight into the brain's computational mechanisms. The first step is to define candidate brain-computational models (BCMs) that can perform the behavioural task in question. We would then like to infer which of the candidate BCMs best accounts for measured brain-activity data. Here we describe a method that complements each BCM by a measurement model (MM), which simulates the way the brain-activity measurements reflect neuronal activity (e.g. local averaging in functional magnetic resonance imaging (fMRI) voxels or sparse sampling in array recordings). The resulting generative model (BCM-MM) produces simulated measurements. To avoid having to fit the MM to predict each individual measurement channel of the brain-activity data, we compare the measured and predicted data at the level of summary statistics. We describe a novel particular implementation of this approach, called probabilistic representational similarity analysis (pRSA) with MMs, which uses representational dissimilarity matrices (RDMs) as the summary statistics. We validate this method by simulations of fMRI measurements (locally averaging voxels) based on a deep convolutional neural network for visual object recognition. Results indicate that the way the measurements sample the activity patterns strongly affects the apparent representational dissimilarities. However, modelling of the measurement process can account for these effects, and different BCMs remain distinguishable even under substantial noise. The pRSA method enables us to perform Bayesian inference on the set of BCMs and to recognize the data-generating model in each case.This article is part of the themed issue 'Interpreting BOLD: a dialogue between cognitive and cellular neuroscience'. PMID:27574316

  1. Neurodegeneration with brain iron accumulation: update on pathogenic mechanisms.

    Directory of Open Access Journals (Sweden)

    Sonia eLevi

    2014-05-01

    Full Text Available Perturbation of iron distribution is observed in many neurodegenerative disorders, including Alzheimer’s and Parkinson’s disease, but the comprehension of the metal role in the development and progression of such disorders is still very limited. The combination of more powerful brain imaging techniques and faster genomic DNA sequencing procedures has allowed the description of a set of genetic disorders characterized by a constant and often early accumulation of iron in specific brain regions and the identification of the associated genes; these disorders are now collectively included in the category of Neurodegeneration with Brain Iron Accumulation (NBIA. So far 10 different genetic forms have been described but this number is likely to increase in short time. Two forms are linked to mutations in genes directly involved in iron metabolism: Neuroferritinopathy, associated to mutations in the FTL gene and Aceruloplasminaemia, where the ceruloplasmin gene product is defective. In the other forms the connection with iron metabolism is not evident at all and the genetic data let infer the involvement of other pathways: Pank2, COASY,Pla2G6, C19orf12, and FA2H genes seem to be related to lipid metabolism and to mitochondria functioning, WDR45 and ATP13A2 genes are implicated in lysosomal and autophagosome activity, while the C2orf37 gene encodes a nucleolar protein of unknown function. There is much hope in the scientific community that the study of the NBIA forms may provide important insight as to the link between brain iron metabolism and neurodegenerative mechanisms and eventually pave the way for new therapeutic avenues also for the more common neurodegenerative disorders. In this work we will review the most recent findings in the molecular mechanisms underlining the most common forms of NBIA and analyze their possible link with brain iron metabolism.

  2. Autonomous control for mechanically stable navigation of microscale implants in brain tissue to record neural activity.

    Science.gov (United States)

    Anand, Sindhu; Kumar, Swathy Sampath; Muthuswamy, Jit

    2016-08-01

    Emerging neural prosthetics require precise positional tuning and stable interfaces with single neurons for optimal function over a lifetime. In this study, we report an autonomous control to precisely navigate microscale electrodes in soft, viscoelastic brain tissue without visual feedback. The autonomous control optimizes signal-to-noise ratio (SNR) of single neuronal recordings in viscoelastic brain tissue while maintaining quasi-static mechanical stress conditions to improve stability of the implant-tissue interface. Force-displacement curves from microelectrodes in in vivo rodent experiments are used to estimate viscoelastic parameters of the brain. Using a combination of computational models and experiments, we determined an optimal movement for the microelectrodes with bidirectional displacements of 3:2 ratio between forward and backward displacements and a inter-movement interval of 40 s for minimizing mechanical stress in the surrounding brain tissue. A regulator with the above optimal bidirectional motion for the microelectrodes in in vivo experiments resulted in significant reduction in the number of microelectrode movements (0.23 movements/min) and longer periods of stable SNR (53 % of the time) compared to a regulator using a conventional linear, unidirectional microelectrode movement (with 1.48 movements/min and stable SNR 23 % of the time). PMID:27457752

  3. Molecular Mechanisms Regulating LPS-Induced Inflammation in the Brain

    Science.gov (United States)

    Lykhmus, Olena; Mishra, Nibha; Koval, Lyudmyla; Kalashnyk, Olena; Gergalova, Galyna; Uspenska, Kateryna; Komisarenko, Serghiy; Soreq, Hermona; Skok, Maryna

    2016-01-01

    Neuro-inflammation, one of the pathogenic causes of neurodegenerative diseases, is regulated through the cholinergic anti-inflammatory pathway via the α7 nicotinic acetylcholine receptor (α7 nAChR). We previously showed that either bacterial lipopolysaccharide (LPS) or immunization with the α7(1–208) nAChR fragment decrease α7 nAChRs density in the mouse brain, exacerbating chronic inflammation, beta-amyloid accumulation and episodic memory decline, which mimic the early stages of Alzheimer’s disease (AD). To study the molecular mechanisms underlying the LPS and antibody effects in the brain, we employed an in vivo model of acute LPS-induced inflammation and an in vitro model of cultured glioblastoma U373 cells. Here, we report that LPS challenge decreased the levels of α7 nAChR RNA and protein and of acetylcholinesterase (AChE) RNA and activity in distinct mouse brain regions, sensitized brain mitochondria to the apoptogenic effect of Ca2+ and modified brain microRNA profiles, including the cholinergic-regulatory CholinomiRs-132/212, in favor of anti-inflammatory and pro-apoptotic ones. Adding α7(1–208)-specific antibodies to the LPS challenge prevented elevation of both the anti-inflammatory and pro-apoptotic miRNAs while supporting the resistance of brain mitochondria to Ca2+ and maintaining α7 nAChR/AChE decreases. In U373 cells, α7-specific antibodies and LPS both stimulated interleukin-6 production through the p38/Src-dependent pathway. Our findings demonstrate that acute LPS-induced inflammation induces the cholinergic anti-inflammatory pathway in the brain, that α7 nAChR down-regulation limits this pathway, and that α7-specific antibodies aggravate neuroinflammation by inducing the pro-inflammatory interleukin-6 and dampening anti-inflammatory miRNAs; however, these antibodies may protect brain mitochondria and decrease the levels of pro-apoptotic miRNAs, preventing LPS-induced neurodegeneration. PMID:27013966

  4. MOLECULAR MECHANISMS REGULATING LPS-INDUCED INFLAMMATION IN THE BRAIN

    Directory of Open Access Journals (Sweden)

    Olena eLykhmus

    2016-03-01

    Full Text Available Neuro-inflammation, one of the pathogenic causes of neurodegenerative diseases, is regulated through the cholinergic anti-inflammatory pathway via the 7 nicotinic acetylcholine receptor (7 nAChR. We previously showed that either bacterial lipopolysaccharide (LPS or immunization with the 7(1-208 nAChR fragment decrease 7 nAChRs density in the mouse brain, exacerbating chronic inflammation, beta-amyloid accumulation and episodic memory decline, which mimic the early stages of Alzheimer’s disease. To study the molecular mechanisms underlying the LPS and antibody effects in the brain, we employed an in vivo model of acute LPS-induced inflammation and an in vitro model of cultured glioblastoma U373 cells. Here, we report that LPS challenge decreased the levels of 7 nAChR RNA and protein and of acetylcholinesterase (AChE RNA and activity in distinct mouse brain regions, sensitized brain mitochondria to the apoptogenic effect of Ca2+ and modified brain microRNA profiles, including the cholinergic-regulatory CholinomiRs-132/212, in favor of anti-inflammatory and pro-apoptotic ones. Adding 7(1-208-specific antibodies to the LPS challenge prevented elevation of both the anti-inflammatory and pro-apoptotic miRNAs while supporting the resistance of brain mitochondria to Ca2+ and maintaining 7 nAChR/AChE decreases. In U373 cells, 7-specific antibodies and LPS both stimulated interleukin-6 production through the p38/Src-dependent pathway. Our findings demonstrate that acute LPS-induced inflammation induces the cholinergic anti-inflammatory pathway in the brain, that 7 nAChR down-regulation limits this pathway, and that 7-specific antibodies aggravate neuroinflammation by inducing the pro-inflammatory interleukin-6 and dampening anti-inflammatory miRNAs; however, these antibodies may protect brain mitochondria and decrease the levels of pro-apoptotic miRNAs, preventing LPS-induced neurodegeneration.

  5. The mechanism of the emergence of distinct overstretched DNA states

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, You-Liang; Sun, Zhao-Yan, E-mail: zysun@ciac.ac.cn [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Lu, Zhong-Yuan [State Key Laboratory of Supramolecular Structure and Materials, Institute of Theoretical Chemistry, Jilin University, Changchun 130023 (China)

    2016-01-14

    Although multiple overstretched DNA states were identified in experiments, the mechanism of the emergence of distinct states is still unclear. Molecular dynamics simulation is an ideal tool to clarify the mechanism, but the force loading rates in stretching achieved by conventional all-atom DNA models are much faster, which essentially affect overstretching states. We employed a modified coarse-grained DNA model with an unprecedented low loading rate in simulations to study the overstretching transitions of end-opened double-stranded DNA. We observed two-strand peeling off for DNA with low stability and the S-DNA with high stability under tension. By introducing a melting-forbidden model which prevents base-pair breaking, we still observed the overstretching transition induced by the formation of S-DNA due to the change of dihedral angle. Hence, we confirmed that the competition between the two strain-softening manners, i.e., base-pair breaking and dihedral angle variation, results in the emergence of distinct overstretched DNA states.

  6. The mechanism of the emergence of distinct overstretched DNA states

    International Nuclear Information System (INIS)

    Although multiple overstretched DNA states were identified in experiments, the mechanism of the emergence of distinct states is still unclear. Molecular dynamics simulation is an ideal tool to clarify the mechanism, but the force loading rates in stretching achieved by conventional all-atom DNA models are much faster, which essentially affect overstretching states. We employed a modified coarse-grained DNA model with an unprecedented low loading rate in simulations to study the overstretching transitions of end-opened double-stranded DNA. We observed two-strand peeling off for DNA with low stability and the S-DNA with high stability under tension. By introducing a melting-forbidden model which prevents base-pair breaking, we still observed the overstretching transition induced by the formation of S-DNA due to the change of dihedral angle. Hence, we confirmed that the competition between the two strain-softening manners, i.e., base-pair breaking and dihedral angle variation, results in the emergence of distinct overstretched DNA states

  7. PREFACE: EmQM13: Emergent Quantum Mechanics 2013

    Science.gov (United States)

    2014-04-01

    These proceedings comprise the invited lectures of the second international symposium on Emergent Quantum Mechanics (EmQM13), which was held at the premises of the Austrian Academy of Sciences in Vienna, Austria, 3-6 October 2013. The symposium was held at the ''Theatersaal'' of the Academy of Sciences, and was devoted to the open exploration of emergent quantum mechanics, a possible ''deeper level theory'' that interconnects three fields of knowledge: emergence, the quantum, and information. Could there appear a revised image of physical reality from recognizing new links between emergence, the quantum, and information? Could a novel synthesis pave the way towards a 21st century, ''superclassical'' physics? The symposium provided a forum for discussing (i) important obstacles which need to be overcome as well as (ii) promising developments and research opportunities on the way towards emergent quantum mechanics. Contributions were invited that presented current advances in both standard as well as unconventional approaches to quantum mechanics. The EmQM13 symposium was co-organized by Gerhard Grössing (Austrian Institute for Nonlinear Studies (AINS), Vienna), and by Jan Walleczek (Fetzer Franklin Fund, USA, and Phenoscience Laboratories, Berlin). After a very successful first conference on the same topic in 2011, the new partnership between AINS and the Fetzer Franklin Fund in producing the EmQM13 symposium was able to further expand interest in the promise of emergent quantum mechanics. The symposium consisted of two parts, an opening evening addressing the general public, and the scientific program of the conference proper. The opening evening took place at the Great Ceremonial Hall (Grosser Festsaal) of the Austrian Academy of Sciences, and it presented talks and a panel discussion on ''The Future of Quantum Mechanics'' with three distinguished speakers: Stephen Adler (Princeton), Gerard 't Hooft (Utrecht) and Masanao Ozawa (Nagoya). The articles contained in

  8. Neural mechanisms underlying neurooptometric rehabilitation following traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Hudac CM

    2012-01-01

    Full Text Available Caitlin M Hudac1, Srinivas Kota1, James L Nedrow2, Dennis L Molfese1,31Department of Psychology, University of Nebraska-Lincoln, 2Oculi Vision Rehabilitation, 3Center for Brain, Biology, and Behavior, University of Nebraska-Lincoln, Lincoln, NEAbstract: Mild to severe traumatic brain injuries have lasting effects on everyday functioning. Issues relating to sensory problems are often overlooked or not addressed until well after the onset of the injury. In particular, vision problems related to ambient vision and the magnocellular pathway often result in posttrauma vision syndrome or visual midline shift syndrome. Symptoms from these syndromes are not restricted to the visual domain. Patients commonly experience proprioceptive, kinesthetic, vestibular, cognitive, and language problems. Neurooptometric rehabilitation often entails the use of corrective lenses, prisms, and binasal occlusion to accommodate the unstable magnocellular system. However, little is known regarding the neural mechanisms engaged during neurooptometric rehabilitation, nor how these mechanisms impact other domains. Event-related potentials from noninvasive electrophysiological recordings can be used to assess rehabilitation progress in patients. In this case report, high-density visual event-related potentials were recorded from one patient with posttrauma vision syndrome and secondary visual midline shift syndrome during a pattern reversal task, both with and without prisms. Results indicate that two factors occurring during the end portion of the P148 component (168–256 milliseconds poststimulus onset map onto two separate neural systems that were engaged with and without neurooptometric rehabilitation. Without prisms, neural sources within somatosensory, language, and executive brain regions engage inefficient magnocellular system processing. However, when corrective prisms were worn, primary visual areas were appropriately engaged. The impact of using early

  9. Autophagy and lysosomal dysfunction as emerging mechanisms of nanomaterial toxicity

    Directory of Open Access Journals (Sweden)

    Stern Stephan T

    2012-06-01

    Full Text Available Abstract The study of the potential risks associated with the manufacture, use, and disposal of nanoscale materials, and their mechanisms of toxicity, is important for the continued advancement of nanotechnology. Currently, the most widely accepted paradigms of nanomaterial toxicity are oxidative stress and inflammation, but the underlying mechanisms are poorly defined. This review will highlight the significance of autophagy and lysosomal dysfunction as emerging mechanisms of nanomaterial toxicity. Most endocytic routes of nanomaterial cell uptake converge upon the lysosome, making the lysosomal compartment the most common intracellular site of nanoparticle sequestration and degradation. In addition to the endo-lysosomal pathway, recent evidence suggests that some nanomaterials can also induce autophagy. Among the many physiological functions, the lysosome, by way of the autophagy (macroautophagy pathway, degrades intracellular pathogens, and damaged organelles and proteins. Thus, autophagy induction by nanoparticles may be an attempt to degrade what is perceived by the cell as foreign or aberrant. While the autophagy and endo-lysosomal pathways have the potential to influence the disposition of nanomaterials, there is also a growing body of literature suggesting that biopersistent nanomaterials can, in turn, negatively impact these pathways. Indeed, there is ample evidence that biopersistent nanomaterials can cause autophagy and lysosomal dysfunctions resulting in toxicological consequences.

  10. Emerging targets for addiction neuropharmacology: From mechanisms to therapeutics.

    Science.gov (United States)

    Ubaldi, Massimo; Cannella, Nazzareno; Ciccocioppo, Roberto

    2016-01-01

    Drug abuse represents a considerable burden of disease and has enormous economic impacts on societies. Over the years, few medications have been developed for clinical use. Their utilization is endowed with several limitations, including partial efficacy or significant side effects. On the other hand, the successful advancement of these compounds provides an important proof of concept for the feasibility of drug development programs in addiction. In recent years, a wealth of information has been generated on the psychological mechanisms, genetic or epigenetic predisposing factors, and neurobiological adaptations induced by drug consumption that interact with each other to contribute to disease progression. It is now clear that addiction develops through phases, from initial recreational use to excessive consumption and compulsive drug seeking, with a shift from positive to negative reinforcement driving motivated behaviors. A greater understanding of these mechanisms has opened new vistas in drug development programs. Researchers' attention has been shifted from investigation of classical targets associated with reward to biological substrates responsible for negative reinforcement, impulse loss of control, and maladaptive mechanisms resulting from protracted drug use. From this research, several new biological targets for the development of innovative therapies have started to emerge. This chapter offers an overview of targets currently under scrutiny for the development of new medications for addiction. This work is not exhaustive but rather it provides a few examples of how this research has advanced in recent years by virtue of studies carried out in our laboratory. PMID:26822362

  11. Orosensory self-stimulation by sucrose involves brain dopaminergic mechanisms.

    Science.gov (United States)

    Schneider, L H

    1989-01-01

    The most convincing body of evidence supporting a role for brain dopaminergic mechanisms in sweet taste reward has been obtained using the sham-feeding rat. In rats prepared with a chronic gastric fistula and tested with the cannula open, intake is a direct function of the palatability of the solution offered as well as of the state of food deprivation. Because essentially none of the ingested fluid passes on to the intestine, negative postingestive feedback is eliminated. Thus, the relative orosensory/hedonic potency of the food determines and sustains the rate of sham intake; long periods of food deprivation are not required. In this way, the sham feeding of sweet solutions may be considered a form of oral self-stimulation behavior and afford a preparation through which the neurochemical and neuranatomical substrates of sweet taste reward may be identified. The results obtained in the series of experiments summarized in this paper clearly indicate that central D-1 and D-2 receptor mechanisms are critical for the orosensory self-stimulation by sucrose in the rat. In conclusion, I suggest that such investigations of the roles of brain dopaminergic mechanisms in the sucrose sham-feeding rat preparation may further our understanding of normal and aberrant attractions to sweet fluids in humans (see Cabanac, Drewnowski, and Halmi, this volume), as an innate, positive affective response of human neonates to sucrose and the sustained positive hedonic ratings for glucose when tasted but not when consumed have demonstrated. PMID:2699194

  12. Molecular Mechanisms of Cognitive Dysfunction following Traumatic Brain Injury

    Directory of Open Access Journals (Sweden)

    Kendall Rae Walker

    2013-07-01

    Full Text Available Traumatic brain injury (TBI results in significant disability due to cognitive deficits particularly in attention, learning and memory and higher-order executive functions. The role of TBI in chronic neurodegeneration and the development of neurodegenerative diseases including Alzheimer’s disease (AD, Parkinson’s disease (PD, Amyotrophic Lateral Sclerosis (ALS and most recently chronic traumatic encephalopathy (CTE is of particular importance. However, despite significant effort very few therapeutic options exist to prevent or reverse cognitive impairment following TBI. In this review we present experimental evidence of the known secondary injury mechanisms which contribute to neuronal cell loss, axonal injury and synaptic dysfunction and hence cognitive impairment both acutely and chronically following TBI. In particular we focus on the mechanisms linking TBI to the development of two forms of dementia: AD and CTE. We provide evidence of potential molecular mechanisms involved in modulating Aβ and Tau following TBI and provide evidence of the role of these mechanisms in AD pathology. Additionally we propose a mechanism by which Aβ generated as a direct result of TBI is capable of exacerbating secondary injury mechanisms thereby establishing a neurotoxic cascade that leads to chronic neurodegeneration.

  13. Cognitive information processing and learning mechanisms of the brain.

    Science.gov (United States)

    Majovski, L V; Jacques, S

    1982-05-01

    The view that the two cerebral hemispheres of the human brain are characterized by different cognitive processing modes that handle information received in various forms is commonly accepted by neurobehavioral scientists and neuropsychologists. Selected neuroanatomical, electrophysiological, neurochemical, biochemical, and neuropsychological data that bear on a cognitive information-processing model of the brain are presented. Processes involved in memory functions are discussed in regard to the nature of thought and the characteristics of mental life, e.g., internalization of thought, perception, arousal, attention, cognitive development, problem solving, the development of cognitive encoding, and selective recall. We present a position that argues for the brain as being flexible vs. fixed in its characteristics and limitations, drawing from various theories and viewpoints. We also present a review of selected mechanisms believed to be involved in brain-behavior processes, e.g., learning, cognition, pain, emotion, reward, cognitive development, and memory formation. A major theme addressed in terms of human information processing is that cognitive functioning, in a variety of instances, comprises subsets of more general processes, e.g., selective recall, cueing that is capable of addressing schemas, notions of inhibition and disinhibition, and the modulation of excitatory properties of certain neural transmitter substances. Questions such as "how is information stored in memory in the first place?" and "how do elements of motivation (i.e., goal orientation) get connected and then send their messages to appropriate inbound behaviors?" are addressed from the point of view that learning, although not understood completely, is somehow involved. Another unresolved question of theoretical and practical significance that we address is "how does learning result in neural connections?" Such questions are discussed in light of their implications for human memory, thought

  14. A brain mechanism for facilitation of insight by positive affect.

    Science.gov (United States)

    Subramaniam, Karuna; Kounios, John; Parrish, Todd B; Jung-Beeman, Mark

    2009-03-01

    Previous research has shown that people solve insight or creative problems better when in a positive mood (assessed or induced), although the precise mechanisms and neural substrates of this facilitation remain unclear. We assessed mood and personality variables in 79 participants before they attempted to solve problems that can be solved by either an insight or an analytic strategy. Participants higher in positive mood solved more problems, and specifically more with insight, compared with participants lower in positive mood. fMRI was performed on 27 of the participants while they solved problems. Positive mood (and to a lesser extent and in the opposite direction, anxiety) was associated with changes in brain activity during a preparatory interval preceding each solved problem; modulation of preparatory activity in several areas biased people to solve either with insight or analytically. Analyses examined whether (a) positive mood modulated activity in brain areas showing responsivity during preparation; (b) positive mood modulated activity in areas showing stronger activity for insight than noninsight trials either during preparation or solution; and (c) insight effects occurred in areas that showed mood-related effects during preparation. Across three analyses, the ACC showed sensitivity to both mood and insight, demonstrating that positive mood alters preparatory activity in ACC, biasing participants to engage in processing conducive to insight solving. This result suggests that positive mood enhances insight, at least in part, by modulating attention and cognitive control mechanisms via ACC, perhaps enhancing sensitivity to detect non-prepotent solution candidates. PMID:18578603

  15. Emergence of Quantum Mechanics from a Sub-Quantum Statistical Mechanics

    Science.gov (United States)

    Grössing, Gerhard

    2015-10-01

    A research program within the scope of theories on "Emergent Quantum Mechanics" is presented, which has gained some momentum in recent years. Via the modeling of a quantum system as a non-equilibrium steady-state maintained by a permanent throughput of energy from the zero-point vacuum, the quantum is considered as an emergent system. We implement a specific "bouncer-walker" model in the context of an assumed sub-quantum statistical physics, in analogy to the results of experiments by Couder and Fort on a classical wave-particle duality. We can thus give an explanation of various quantum mechanical features and results on the basis of a "21st century classical physics", such as the appearance of Planck's constant, the Schrödinger equation, etc. An essential result is given by the proof that averaged particle trajectories' behaviors correspond to a specific type of anomalous diffusion termed "ballistic" diffusion on a sub-quantum level...

  16. Alcohol Withdrawal and Brain Injuries: Beyond Classical Mechanisms

    Directory of Open Access Journals (Sweden)

    Marianna E. Jung

    2010-07-01

    Full Text Available Unmanaged sudden withdrawal from the excessive consumption of alcohol (ethanol adversely alters neuronal integrity in vulnerable brain regions such as the cerebellum, hippocampus, or cortex. In addition to well known hyperexcitatory neurotransmissions, ethanol withdrawal (EW provokes the intense generation of reactive oxygen species (ROS and the activation of stress-responding protein kinases, which are the focus of this review article. EW also inflicts mitochondrial membranes/membrane potential, perturbs redox balance, and suppresses mitochondrial enzymes, all of which impair a fundamental function of mitochondria. Moreover, EW acts as an age-provoking stressor. The vulnerable age to EW stress is not necessarily the oldest age and varies depending upon the target molecule of EW. A major female sex steroid, 17β-estradiol (E2, interferes with the EW-induced alteration of oxidative signaling pathways and thereby protects neurons, mitochondria, and behaviors. The current review attempts to provide integrated information at the levels of oxidative signaling mechanisms by which EW provokes brain injuries and E2 protects against it. Unmanaged sudden withdrawal from the excessive consumption of alcohol (ethanol adversely alters neuronal integrity in vulnerable brain regions such as the cerebellum, hippocampus, or cortex. In addition to well known hyperexcitatory neurotransmissions, ethanol withdrawal (EW provokes the intense generation of reactive oxygen species (ROS and the activation of stress-responding protein kinases, which are the focus of this review article. EW also inflicts mitochondrial membranes/membrane potential, perturbs redox balance, and suppresses mitochondrial enzymes, all of which impair a fundamental function of mitochondria. Moreover, EW acts as an age-provoking stressor. The vulnerable age to EW stress is not necessarily the oldest age and varies depending upon the target molecule of EW. A major female sex steroid, 17

  17. Pictures as a neurological tool: lessons from enhanced and emergent artistry in brain disease.

    Science.gov (United States)

    Schott, G D

    2012-06-01

    Pictures created spontaneously by patients with brain disease often display impaired or diminished artistry, reflecting the patient's cerebral damage. This article explores the opposite: those pictures created in the face of brain disease that show enhanced or enduring artistry, and those that emerge for the first time in artistically naïve patients. After comments on background issues relating to the patient and the viewer, the paintings and drawings are considered in relation to the heterogeneous conditions in which this artistic creativity is seen. These conditions include various dementias-most notably frontotemporal lobar dementia, stroke, Parkinson's disease, autism and related disorders and psychiatric disease, epilepsy, migraine and trauma. In the discussion, it is argued that evidence of underlying brain dysfunction revealed by these pictures often rests on the abnormal context in which the pictures are created, or on changes in artistry demonstrated by a sequence of pictures. In the former, the compulsive element and sensory and emotional accompaniments are often important features; in the latter, evolving changes are evident, and have included depiction of increasing menace in portrayal of faces. The occurrence of synaesthesia, and its relation to creativity, are briefly discussed in respect of two unusual patients, followed by considering the role of the anterior and frontal lobes, mesolimbic connections and the right hemisphere. In at least some patients, impaired inhibition leading to paradoxical functional facilitation, with compensatory changes particularly in the right posterior hemisphere, is likely to be pivotal in enabling unusual artistry to emerge; preservation of language, however, is not a prerequisite. Many patients studied have been artists, and it appears possible that some of those with an artistic predisposition may be more likely to experience pathologically obsessive creativity. The discussion concludes that occasionally pictures

  18. Boundaries as Mechanisms for Learning in Emergency Exercises with Students from Emergency Service Organisations

    Science.gov (United States)

    Andersson, Annika

    2016-01-01

    To prepare emergency response organisations for collaborative work in unpredictable and dynamic situations, various types of exercises are widely used. Still, our knowledge of collaboration exercises with emergency response students is limited. This study aimed to contribute to this field by exploring boundaries that emerged between collaborating…

  19. Developmental modes and developmental mechanisms can channel brain evolution

    Directory of Open Access Journals (Sweden)

    Christine J Charvet

    2011-02-01

    Full Text Available Anseriform birds (ducks and geese as well as parrots and songbirds have evolved a disproportionately enlarged telencephalon compared with many other birds. However, parrots and songbirds differ from anseriform birds in their mode of development. Whereas ducks and geese are precocial (e.g., hatchlings feed on their own, parrots and songbirds are altricial (e.g., hatchlings are fed by their parents. We here consider how developmental modes may limit and facilitate specific changes in the mechanisms of brain development. We suggest that altriciality facilitates the evolution of telencephalic expansion by delaying telencephalic neurogenesis. We further hypothesize that delays in telencephalic neurogenesis generate delays in telencephalic maturation, which in turn foster neural adaptations that facilitate learning. Specifically, we propose that delaying telencephalic neurogenesis was a prerequisite for the evolution of neural circuits that allow parrots and songbirds to produce learned vocalizations. Overall, we argue that developmental modes have influenced how some lineages of birds increased the size of their telencephalon and that this, in turn, has influenced subsequent changes in brain circuits and behavior.

  20. Developmental Modes and Developmental Mechanisms can Channel Brain Evolution.

    Science.gov (United States)

    Charvet, Christine J; Striedter, Georg F

    2011-01-01

    Anseriform birds (ducks and geese) as well as parrots and songbirds have evolved a disproportionately enlarged telencephalon compared with many other birds. However, parrots and songbirds differ from anseriform birds in their mode of development. Whereas ducks and geese are precocial (e.g., hatchlings feed on their own), parrots and songbirds are altricial (e.g., hatchlings are fed by their parents). We here consider how developmental modes may limit and facilitate specific changes in the mechanisms of brain development. We suggest that altriciality facilitates the evolution of telencephalic expansion by delaying telencephalic neurogenesis. We further hypothesize that delays in telencephalic neurogenesis generate delays in telencephalic maturation, which in turn foster neural adaptations that facilitate learning. Specifically, we propose that delaying telencephalic neurogenesis was a prerequisite for the evolution of neural circuits that allow parrots and songbirds to produce learned vocalizations. Overall, we argue that developmental modes have influenced how some lineages of birds increased the size of their telencephalon and that this, in turn, has influenced subsequent changes in brain circuits and behavior.

  1. Androgen modulation of social decision making mechanisms in the brain: an integrative and embodied perspective

    Directory of Open Access Journals (Sweden)

    Rui F Oliveira

    2014-07-01

    Full Text Available Apart from their role in reproduction androgens also respond to social challenges and this response has been seen as a way to regulate the expression of behaviour according to the perceived social environment (Challenge hypothesis, Wingfield et al. 1990. This hypothesis implies that social decision-making mechanisms localized in the central nervous system (CNS are open to the influence of peripheral hormones that ultimately are under the control of the CNS through the hypothalamic-pituitary-gonadal axis. Therefore, two puzzling questions emerge at two different levels of biological analysis: (1 Why does the brain, which perceives the social environment and regulates androgen production in the gonad, need feedback information from the gonad to adjust its social decision-making processes? (2 How does the brain regulate gonadal androgen responses to social challenges and how do these feedback into the brain? In this paper, we will address these two questions using the integrative approach proposed by Niko Tinbergen, who proposed that a full understanding of behaviour requires its analysis at both proximate (physiology, ontogeny and ultimate (ecology, evolution levels.

  2. How does our brain constitute defense mechanisms? First-person neuroscience and psychoanalysis.

    Science.gov (United States)

    Northoff, Georg; Bermpohl, Felix; Schoeneich, Frank; Boeker, Heinz

    2007-01-01

    Current progress in the cognitive and affective neurosciences is constantly influencing the development of psychoanalytic theory and practice. However, despite the emerging dialogue between neuroscience and psychoanalysis, the neuronal processes underlying psychoanalytic constructs such as defense mechanisms remain unclear. One of the main problems in investigating the psychodynamic-neuronal relationship consists in systematically linking the individual contents of first-person subjective experience to third-person observation of neuronal states. We therefore introduced an appropriate methodological strategy, 'first-person neuroscience', which aims at developing methods for systematically linking first- and third-person data. The utility of first-person neuroscience can be demonstrated by the example of the defense mechanism of sensorimotor regression as paradigmatically observed in catatonia. Combined psychodynamic and imaging studies suggest that sensorimotor regression might be associated with dysfunction in the neural network including the orbitofrontal, the medial prefrontal and the premotor cortices. In general sensorimotor regression and other defense mechanisms are psychoanalytic constructs that are hypothesized to be complex emotional-cognitive constellations. In this paper we suggest that specific functional mechanisms which integrate neuronal activity across several brain regions (i.e. neuronal integration) are the physiological substrates of defense mechanisms. We conclude that first-person neuroscience could be an appropriate methodological strategy for opening the door to a better understanding of the neuronal processes of defense mechanisms and their modulation in psychoanalytic psychotherapy. PMID:17426413

  3. Research on Group Decision-Making Mechanism of Internet Emergency Management

    Science.gov (United States)

    Xie, Kefan; Chen, Gang; Qian, Wu; Shi, Zhao

    With the development of information technology, internet has become a popular term and internet emergency has an intensive influence on people's life. This article offers a short history of internet emergency management. It discusses the definition, characteristics, and factor of internet emergency management. A group decision-making mechanism of internet emergency is presented based on the discussion. The authors establish a so-called Rough Set Scenario Flow Graphs (RSSFG) of group decision-making mechanism of internet emergency management and make an empirical analysis based on the RSSFG approach. The experimental results confirm that this approach is effective in internet emergency decision-making.

  4. A Thoracic Mechanism of Mild Traumatic Brain Injury Due to Blast Pressure Waves

    OpenAIRE

    Courtney, Amy; Courtney, Michael

    2008-01-01

    The mechanisms by which blast pressure waves cause mild to moderate traumatic brain injury (mTBI) are an open question. Possibilities include acceleration of the head, direct passage of the blast wave via the cranium, and propagation of the blast wave to the brain via a thoracic mechanism. The hypothesis that the blast pressure wave reaches the brain via a thoracic mechanism is considered in light of ballistic and blast pressure wave research. Ballistic pressure waves, caused by penetrating b...

  5. Brain glycogen

    DEFF Research Database (Denmark)

    Obel, Linea Lykke Frimodt; Müller, Margit S; Walls, Anne B;

    2012-01-01

    Glycogen is a complex glucose polymer found in a variety of tissues, including brain, where it is localized primarily in astrocytes. The small quantity found in brain compared to e.g., liver has led to the understanding that brain glycogen is merely used during hypoglycemia or ischemia....... In this review evidence is brought forward highlighting what has been an emerging understanding in brain energy metabolism: that glycogen is more than just a convenient way to store energy for use in emergencies-it is a highly dynamic molecule with versatile implications in brain function, i.e., synaptic...... activity and memory formation. In line with the great spatiotemporal complexity of the brain and thereof derived focus on the basis for ensuring the availability of the right amount of energy at the right time and place, we here encourage a closer look into the molecular and subcellular mechanisms...

  6. Emergency care of traumatic brain injuries in Pakistan: a multicenter study

    Science.gov (United States)

    2015-01-01

    Background This study assessed factors associated with emergency care outcomes and out-of-pocket treatment costs in traumatic brain injury (TBI) patients in Pakistan. Methods Data on TBI patients were extracted from a four-month surveillance study conducted in the emergency departments (ED) of seven large teaching hospitals. Emergency care access to physicians and imaging facilities were compared with respect to ED outcomes (discharged, admitted or dead). Out-of-pocket treatment costs (in United States dollars [USD]) were compared among different patient strata. Results ED outcomes were available for 1,787 TBI patients. Of them, most were males (79%), aged privileges (medical officers, residents or consultants) saw about half (55%) of them. Computerized tomography (CT) scans were performed in two of five patients (40%). Of all, 26% (n = 460) were admitted and 3% died (n = 52). Emergency care factors significantly associated with being admitted or died were arriving by ambulance (adjusted odds ratio [aOR] = 2.37, 95% confidence interval (CI) [95%CI] = 1.78-3.16); seen by medical officer/residents (aOR = 2.11; 95%CI = 1.49-2.99); and had CT scan (aOR = 2.93; 95%CI = 2.25-3.83). Out-of-pocket treatment costs at the ED were reported in 803 patients. Average costs were USD 8, (standard deviation [SD] = 23). Costs were twice as high in those arriving in ambulances (USD 20, SD = 49) or who underwent CT scans (USD 16, SD = 37). Conclusion TBI patients' access to ambulance transport, experienced physicians, and imaging facilities during emergency care needs to be improved in Pakistan. PMID:26691277

  7. Characterization of multiciliated ependymal cells that emerge in the neurogenic niche of the aged zebrafish brain.

    Science.gov (United States)

    Ogino, Takashi; Sawada, Masato; Takase, Hiroshi; Nakai, Chiemi; Herranz-Pérez, Vicente; Cebrián-Silla, Arantxa; Kaneko, Naoko; García-Verdugo, José Manuel; Sawamoto, Kazunobu

    2016-10-15

    In mammals, ventricular walls of the developing brain maintain a neurogenic niche, in which radial glial cells act as neural stem cells (NSCs) and generate new neurons in the embryo. In the adult brain, the neurogenic niche is maintained in the ventricular-subventricular zone (V-SVZ) of the lateral wall of lateral ventricles and the hippocampal dentate gyrus. In the neonatal V-SVZ, radial glial cells transform into astrocytic postnatal NSCs and multiciliated ependymal cells. On the other hand, in zebrafish, radial glial cells continue to cover the surface of the adult telencephalic ventricle and maintain a higher neurogenic potential in the adult brain. However, the cell composition of the neurogenic niche of the aged zebrafish brain has not been investigated. Here we show that multiciliated ependymal cells emerge in the neurogenic niche of the aged zebrafish telencephalon. These multiciliated cells appear predominantly in the dorsal part of the ventral telencephalic ventricular zone, which also contains clusters of migrating new neurons. Scanning electron microscopy and live imaging analyses indicated that these multiple cilia beat coordinately and generate constant fluid flow within the ventral telencephalic ventricle. Analysis of the cell composition by transmission electron microscopy revealed that the neurogenic niche in the aged zebrafish contains different types of cells, with ultrastructures similar to those of ependymal cells, transit-amplifying cells, and migrating new neurons in postnatal mice. These data suggest that the transformation capacity of radial glial cells is conserved but that its timing is different between fish and mice. J. Comp. Neurol. 524:2982-2992, 2016. © 2016 Wiley Periodicals, Inc. PMID:26991819

  8. A Scalable Communication Mechanism in Service Emergence Based on Bio-network

    Institute of Scientific and Technical Information of China (English)

    SUN Hong-bin; DING Yong-sheng

    2008-01-01

    A scalable communication mechanism is proposed for service emergence based on bio-network. Service emergence is a novel model inspired by the characteristics of emergence and self-evolution in biological neuroendocrine and ininlune system,emergent conununication means a group conununication of mobile bio-entities. A series of protocol and algorithm are presented within frequently bioentities migration and failure,it includes distribution and parailelization of message propagation method,a token-ring protocol that considerably improves the performance of emergence,and failure detection mechanisms.Experiment results show the desired capability via the proposed solution.

  9. Neural mechanisms of face perception, their emergence over development, and their breakdown.

    Science.gov (United States)

    Behrmann, Marlene; Scherf, K Suzanne; Avidan, Galia

    2016-07-01

    Face perception is probably the most developed visual perceptual skill in humans, most likely as a result of its unique evolutionary and social significance. Much recent research has converged to identify a host of relevant psychological mechanisms that support face recognition. In parallel, there has been substantial progress in uncovering the neural mechanisms that mediate rapid and accurate face perception, with specific emphasis on a broadly distributed neural circuit, comprised of multiple nodes whose joint activity supports face perception. This article focuses specifically on the neural underpinnings of face recognition, and reviews recent structural and functional imaging studies that elucidate the neural basis of this ability. In addition, the article covers some of the recent investigations that characterize the emergence of the neural basis of face recognition over the course of development, and explores the relationship between these changes and increasing behavioural competence. This paper also describes studies that characterize the nature of the breakdown of face recognition in individuals who are impaired in face recognition, either as a result of brain damage acquired at some point or as a result of the failure to master face recognition over the course of development. Finally, information regarding similarities between the neural circuits for face perception in humans and in nonhuman primates is briefly covered, as is the contribution of subcortical regions to face perception. WIREs Cogn Sci 2016, 7:247-263. doi: 10.1002/wcs.1388 For further resources related to this article, please visit the WIREs website. PMID:27196333

  10. Theory of brain function, quantum mechanics and superstrings

    CERN Document Server

    Nanopoulos, Dimitri V

    1995-01-01

    Recent developments/efforts to understand aspects of the brain function at the {\\em sub-neural} level are discussed. MicroTubules (MTs) participate in a wide variety of dynamical processes in the cell especially in bioinformation processes such as learning and memory, by possessing a well-known binary error-correcting code with 64 words. In fact, MTs and DNA/RNA are unique cell structures that possess a code system. It seems that the MTs' code system is strongly related to a kind of ``Mental Code" in the following sense. The MTs' periodic paracrystalline structure make them able to support a superposition of coherent quantum states, as it has been recently conjectured by Hameroff and Penrose, representing an external or mental order, for sufficient time needed for efficient quantum computing. Then the quantum superposition collapses spontaneously/dynamically through a new, string-derived mechanism for collapse proposed recently by Ellis, Mavromatos, and myself. At the moment of collapse, organized quantum exo...

  11. The emerging use of ketamine for anesthesia and sedation in traumatic brain injuries.

    Science.gov (United States)

    Chang, Lee C; Raty, Sally R; Ortiz, Jaime; Bailard, Neil S; Mathew, Sanjay J

    2013-06-01

    Traditionally, the use of ketamine for patients with traumatic brain injuries is contraindicated due to the concern of increasing intracranial pressure (ICP). These concerns, however, originated from early studies and case reports that were inadequately controlled and designed. Recently, the concern of using ketamine in these patients has been challenged by a number of published studies demonstrating that the use of ketamine was safe in these patients. This article reviews the current literature in regards to using ketamine in patients with traumatic brain injuries in different clinical settings associated with anesthesia, as well as reviews the potential mechanisms underlying the neuroprotective effects of ketamine. Studies examining the use of ketamine for induction, maintenance, and sedation in patients with TBI have had promising results. The use of ketamine in a controlled ventilation setting and in combination with other sedative agents has demonstrated no increase in ICP. The role of ketamine as a neuroprotective agent in humans remains inconclusive and adequately powered; randomized controlled trials performed in patients undergoing surgery for traumatic brain injury are necessary.

  12. Parsing the Behavioral and Brain Mechanisms of Third-Party Punishment

    Science.gov (United States)

    Bonnie, Richard J.; Hoffman, Morris B.; Shen, Francis X.; Simons, Kenneth W.

    2016-01-01

    The evolved capacity for third-party punishment is considered crucial to the emergence and maintenance of elaborate human social organization and is central to the modern provision of fairness and justice within society. Although it is well established that the mental state of the offender and the severity of the harm he caused are the two primary predictors of punishment decisions, the precise cognitive and brain mechanisms by which these distinct components are evaluated and integrated into a punishment decision are poorly understood. Using fMRI, here we implement a novel experimental design to functionally dissociate the mechanisms underlying evaluation, integration, and decision that were conflated in previous studies of third-party punishment. Behaviorally, the punishment decision is primarily defined by a superadditive interaction between harm and mental state, with subjects weighing the interaction factor more than the single factors of harm and mental state. On a neural level, evaluation of harms engaged brain areas associated with affective and somatosensory processing, whereas mental state evaluation primarily recruited circuitry involved in mentalization. Harm and mental state evaluations are integrated in medial prefrontal and posterior cingulate structures, with the amygdala acting as a pivotal hub of the interaction between harm and mental state. This integrated information is used by the right dorsolateral prefrontal cortex at the time of the decision to assign an appropriate punishment through a distributed coding system. Together, these findings provide a blueprint of the brain mechanisms by which neutral third parties render punishment decisions. SIGNIFICANCE STATEMENT Punishment undergirds large-scale cooperation and helps dispense criminal justice. Yet it is currently unknown precisely how people assess the mental states of offenders, evaluate the harms they caused, and integrate those two components into a single punishment decision. Using a

  13. The emergence of mind and brain: an evolutionary, computational, and philosophical approach.

    Science.gov (United States)

    Mainzer, Klaus

    2008-01-01

    Modern philosophy of mind cannot be understood without recent developments in computer science, artificial intelligence (AI), robotics, neuroscience, biology, linguistics, and psychology. Classical philosophy of formal languages as well as symbolic AI assume that all kinds of knowledge must explicitly be represented by formal or programming languages. This assumption is limited by recent insights into the biology of evolution and developmental psychology of the human organism. Most of our knowledge is implicit and unconscious. It is not formally represented, but embodied knowledge, which is learnt by doing and understood by bodily interacting with changing environments. That is true not only for low-level skills, but even for high-level domains of categorization, language, and abstract thinking. The embodied mind is considered an emergent capacity of the brain as a self-organizing complex system. Actually, self-organization has been a successful strategy of evolution to handle the increasing complexity of the world. Genetic programs are not sufficient and cannot prepare the organism for all kinds of complex situations in the future. Self-organization and emergence are fundamental concepts in the theory of complex dynamical systems. They are also applied in organic computing as a recent research field of computer science. Therefore, cognitive science, AI, and robotics try to model the embodied mind in an artificial evolution. The paper analyzes these approaches in the interdisciplinary framework of complex dynamical systems and discusses their philosophical impact. PMID:18166390

  14. Nitric Oxide Inactivation Mechanisms in the Brain: Role in Bioenergetics and Neurodegeneration

    Directory of Open Access Journals (Sweden)

    Ricardo M. Santos

    2012-01-01

    Full Text Available During the last decades nitric oxide (•NO has emerged as a critical physiological signaling molecule in mammalian tissues, notably in the brain. •NO may modify the activity of regulatory proteins via direct reaction with the heme moiety, or indirectly, via S-nitrosylation of thiol groups or nitration of tyrosine residues. However, a conceptual understanding of how •NO bioactivity is carried out in biological systems is hampered by the lack of knowledge on its dynamics in vivo. Key questions still lacking concrete and definitive answers include those related with quantitative issues of its concentration dynamics and diffusion, summarized in the how much, how long, and how far trilogy. For instance, a major problem is the lack of knowledge of what constitutes a physiological •NO concentration and what constitutes a pathological one and how is •NO concentration regulated. The ambient •NO concentration reflects the balance between the rate of synthesis and the rate of breakdown. Much has been learnt about the mechanism of •NO synthesis, but the inactivation pathways of •NO has been almost completely ignored. We have recently addressed these issues in vivo on basis of microelectrode technology that allows a fine-tuned spatial and temporal measurement •NO concentration dynamics in the brain.

  15. Emerging Security Mechanisms for Medical Cyber Physical Systems.

    Science.gov (United States)

    Kocabas, Ovunc; Soyata, Tolga; Aktas, Mehmet K

    2016-01-01

    The following decade will witness a surge in remote health-monitoring systems that are based on body-worn monitoring devices. These Medical Cyber Physical Systems (MCPS) will be capable of transmitting the acquired data to a private or public cloud for storage and processing. Machine learning algorithms running in the cloud and processing this data can provide decision support to healthcare professionals. There is no doubt that the security and privacy of the medical data is one of the most important concerns in designing an MCPS. In this paper, we depict the general architecture of an MCPS consisting of four layers: data acquisition, data aggregation, cloud processing, and action. Due to the differences in hardware and communication capabilities of each layer, different encryption schemes must be used to guarantee data privacy within that layer. We survey conventional and emerging encryption schemes based on their ability to provide secure storage, data sharing, and secure computation. Our detailed experimental evaluation of each scheme shows that while the emerging encryption schemes enable exciting new features such as secure sharing and secure computation, they introduce several orders-of-magnitude computational and storage overhead. We conclude our paper by outlining future research directions to improve the usability of the emerging encryption schemes in an MCPS. PMID:26812732

  16. Emerging Security Mechanisms for Medical Cyber Physical Systems.

    Science.gov (United States)

    Kocabas, Ovunc; Soyata, Tolga; Aktas, Mehmet K

    2016-01-01

    The following decade will witness a surge in remote health-monitoring systems that are based on body-worn monitoring devices. These Medical Cyber Physical Systems (MCPS) will be capable of transmitting the acquired data to a private or public cloud for storage and processing. Machine learning algorithms running in the cloud and processing this data can provide decision support to healthcare professionals. There is no doubt that the security and privacy of the medical data is one of the most important concerns in designing an MCPS. In this paper, we depict the general architecture of an MCPS consisting of four layers: data acquisition, data aggregation, cloud processing, and action. Due to the differences in hardware and communication capabilities of each layer, different encryption schemes must be used to guarantee data privacy within that layer. We survey conventional and emerging encryption schemes based on their ability to provide secure storage, data sharing, and secure computation. Our detailed experimental evaluation of each scheme shows that while the emerging encryption schemes enable exciting new features such as secure sharing and secure computation, they introduce several orders-of-magnitude computational and storage overhead. We conclude our paper by outlining future research directions to improve the usability of the emerging encryption schemes in an MCPS.

  17. Fracture mechanics of concrete: Will applications start to emerge?

    NARCIS (Netherlands)

    Van Mier, J.G.M.

    1995-01-01

    Fracture mechanics of concrete has developed into an active field of research in the past decades. It promises a rational solution technique to structural problems in reinforced concrete in the limit state. Numerical tools have been developed on the basis of fracture mechanics theories. The question

  18. Brain mechanisms of acoustic communication in humans and nonhuman primates: an evolutionary perspective.

    Science.gov (United States)

    Ackermann, Hermann; Hage, Steffen R; Ziegler, Wolfram

    2014-12-01

    Any account of "what is special about the human brain" (Passingham 2008) must specify the neural basis of our unique ability to produce speech and delineate how these remarkable motor capabilities could have emerged in our hominin ancestors. Clinical data suggest that the basal ganglia provide a platform for the integration of primate-general mechanisms of acoustic communication with the faculty of articulate speech in humans. Furthermore, neurobiological and paleoanthropological data point at a two-stage model of the phylogenetic evolution of this crucial prerequisite of spoken language: (i) monosynaptic refinement of the projections of motor cortex to the brainstem nuclei that steer laryngeal muscles, presumably, as part of a "phylogenetic trend" associated with increasing brain size during hominin evolution; (ii) subsequent vocal-laryngeal elaboration of cortico-basal ganglia circuitries, driven by human-specific FOXP2 mutations.;>This concept implies vocal continuity of spoken language evolution at the motor level, elucidating the deep entrenchment of articulate speech into a "nonverbal matrix" (Ingold 1994), which is not accounted for by gestural-origin theories. Moreover, it provides a solution to the question for the adaptive value of the "first word" (Bickerton 2009) since even the earliest and most simple verbal utterances must have increased the versatility of vocal displays afforded by the preceding elaboration of monosynaptic corticobulbar tracts, giving rise to enhanced social cooperation and prestige. At the ontogenetic level, the proposed model assumes age-dependent interactions between the basal ganglia and their cortical targets, similar to vocal learning in some songbirds. In this view, the emergence of articulate speech builds on the "renaissance" of an ancient organizational principle and, hence, may represent an example of "evolutionary tinkering" (Jacob 1977). PMID:24827156

  19. The mechanisms of action of deep brain stimulation and ideas for the future development.

    Science.gov (United States)

    Udupa, Kaviraja; Chen, Robert

    2015-10-01

    Deep brain stimulation (DBS) has been used as a treatment of movement disorders such as Parkinson's disease, dystonia, and essential tremor for over twenty years, and is a promising treatment for depression and epilepsy. However, the exact mechanisms of action of DBS are still uncertain, although different theories have emerged. This review summarizes the current understanding in this field. Different modalities used to investigate DBS such as electrophysiological, imaging and biochemical studies have revealed different mechanisms of DBS. The mechanisms may also be different depending on the structure targeted, the disease condition or the animal model employed. DBS may inhibit the target neuronal networks but activate the efferent axons. It may suppress pathological rhythms or impose new rhythms associated with beneficial effects, and involves neuronal networks with widespread connections. Different neurotransmitter systems such as dopamine and GABA upregulation are involved in the effects of DBS. There are also technical advances to prolong the battery life and specific targeting based on new electrode designs with multiple contacts which have the ability to steer the current toward a specific direction. There is ongoing work in closed loop or adaptive DBS using neural oscillations to provide the feedback signals. These oscillations need to be better characterized in a wide variety of clinical settings in future studies. Individualization of DBS parameters based on neural oscillations may optimize the clinical benefits of DBS. PMID:26296674

  20. Effects of physician-based emergency medical service dispatch in severe traumatic brain injury on prehospital run time

    NARCIS (Netherlands)

    Franschman, G.; Verburg, N.; Brens-Heldens, V.; Andriessen, T.M.J.C.; Naalt, J. van der; Peerdeman, S.M.; Valk, J.P.M. van der; Hoogerwerf, N.; Greuters, S.; Schober, P.; Vos, P.E.; Christiaans, H.M.; Boer, C.

    2012-01-01

    INTRODUCTION: Prehospital care by physician-based helicopter emergency medical services (P-HEMS) may prolong total prehospital run time. This has raised an issue of debate about the benefits of these services in traumatic brain injury (TBI). We therefore investigated the effects of P-HEMS dispatch o

  1. Effects of physician-based emergency medical service dispatch in severe traumatic brain injury on prehospital run time

    NARCIS (Netherlands)

    Franschman, G.; Verburg, N.; Brens-Heldens, V.; Andriessen, T. M. J. C.; Van der Naalt, J.; Peerdeman, S. M.; Hoogerwerf, N.; Greuters, S.; Schober, P.; Vos, P. E.; Christiaans, H. M. T.; Boer, C.; Valk, J.P.

    2012-01-01

    Introduction: Prehospital care by physician-based helicopter emergency medical services (P-HEMS) may prolong total prehospital run time. This has raised an issue of debate about the benefits of these services in traumatic brain injury (TBI). We therefore investigated the effects of P-HEMS dispatch o

  2. Mechanisms and functions of brain and behavioural asymmetries

    OpenAIRE

    Tommasi, Luca

    2008-01-01

    For almost a century the field of brain and behavioural asymmetries has been dominated by studies on humans, resting on the evidence that the anatomical structures underlying language functions are asymmetrical, and that human handedness is lateralized at the population level. Today, there is not only evidence of population-level lateralization of brain and behaviour across a variety of vertebrate and invertebrate species, but also a growing consensus that the comparative analysis of the envi...

  3. Mechanosensitive subcellular rheostasis drives emergent single-cell mechanical homeostasis

    Science.gov (United States)

    Weng, Shinuo; Shao, Yue; Chen, Weiqiang; Fu, Jianping

    2016-09-01

    Mechanical homeostasis--a fundamental process by which cells maintain stable states under environmental perturbations--is regulated by two subcellular mechanotransducers: cytoskeleton tension and integrin-mediated focal adhesions (FAs). Here, we show that single-cell mechanical homeostasis is collectively driven by the distinct, graduated dynamics (rheostasis) of subcellular cytoskeleton tension and FAs. Such rheostasis involves a mechanosensitive pattern wherein ground states of cytoskeleton tension and FA determine their distinct reactive paths through either relaxation or reinforcement. Pharmacological perturbations of the cytoskeleton and molecularly modulated integrin catch-slip bonds biased the rheostasis and induced non-homeostasis of FAs, but not of cytoskeleton tension, suggesting a unique sensitivity of FAs in regulating homeostasis. Theoretical modelling revealed myosin-mediated cytoskeleton contractility and catch-slip-bond-like behaviours in FAs and the cytoskeleton as sufficient and necessary mechanisms for quantitatively recapitulating mechanosensitive rheostasis. Our findings highlight the previously underappreciated physical nature of the mechanical homeostasis of cells.

  4. Minimally Complex Exchange Mechanisms: Emergence of Prices, Markets, and Money

    OpenAIRE

    Pradeep Dubey; Siddhartha Sahi; Martin Shubik

    2014-01-01

    We consider abstract exchange mechanisms wherein individuals submit "diversified" offers in m commodities, which are then redistributed to them. Our first result is that if the mechanism satisfies certain natural conditions embodying "fairness" and "convenience" then it admits unique prices, in the sense of consistent exchange-rates across commodity pairs ij that equalize the valuation of offers and returns for each individual. We next define certain integers tau_{ij}, pi_{ij}, and k_{i} whic...

  5. 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 ...

  6. 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...

  7. Many worlds and the emergence of probability in quantum mechanics

    OpenAIRE

    Van Wesep, Robert A.

    2005-01-01

    The interpretation of the squared norm as probability and the apparent stochastic nature of observation in quantum mechanics are derived from the strong law of large numbers and the algebraic properties of infinite sequences of simultaneous quantum observables. It is argued that this result validates the many-worlds view of quantum reality.

  8. Characterizing Multiscale Mechanical Properties of Brain Tissue Using Atomic Force Microscopy, Impact Indentation, and Rheometry.

    Science.gov (United States)

    Canovic, Elizabeth Peruski; Qing, Bo; Mijailovic, Aleksandar S; Jagielska, Anna; Whitfield, Matthew J; Kelly, Elyza; Turner, Daria; Sahin, Mustafa; Van Vliet, Krystyn J

    2016-01-01

    To design and engineer materials inspired by the properties of the brain, whether for mechanical simulants or for tissue regeneration studies, the brain tissue itself must be well characterized at various length and time scales. Like many biological tissues, brain tissue exhibits a complex, hierarchical structure. However, in contrast to most other tissues, brain is of very low mechanical stiffness, with Young's elastic moduli E on the order of 100s of Pa. This low stiffness can present challenges to experimental characterization of key mechanical properties. Here, we demonstrate several mechanical characterization techniques that have been adapted to measure the elastic and viscoelastic properties of hydrated, compliant biological materials such as brain tissue, at different length scales and loading rates. At the microscale, we conduct creep-compliance and force relaxation experiments using atomic force microscope-enabled indentation. At the mesoscale, we perform impact indentation experiments using a pendulum-based instrumented indenter. At the macroscale, we conduct parallel plate rheometry to quantify the frequency dependent shear elastic moduli. We also discuss the challenges and limitations associated with each method. Together these techniques enable an in-depth mechanical characterization of brain tissue that can be used to better understand the structure of brain and to engineer bio-inspired materials. PMID:27684097

  9. Role of brain CT scan in the diagnosis of patients with minor head injury in trauma emergency center

    Directory of Open Access Journals (Sweden)

    Ali Mousavi Jafarabad

    2014-07-01

    Full Text Available Currently, a large burden of hospital admissions is related to minor head trauma and its related imaging studies. One of the challenging issues for emergency physicians is brain computed tomography scan. Sensible use of computed tomography studies could minimize unnecessary radiation exposure and resource use. On the other hand, it can result in delayed or missed early treatment of intracranial injury. The aim of this review is to evaluate and summarize the costs and benefits of using diagnostic measurements in minor head trauma with particular focus on computed tomography scan and the advances and limitations of available guidelines. We studied different issues related to the current approach to minor head trauma in emergency departments. Altogether, it seems using brain computed tomography scan in the setting of emergency is a cost-effective method for the selected patients with minor head injury. However, concerning considerable costs of caring for patients with head injury and high sensitivity of brain computed tomography in terms of minor head injury, it seems reasonable to use brain computed tomography scan for a wider range of patients with minor head injury.

  10. The emerging threat of superwarfarins: history, detection, mechanisms, and countermeasures.

    Science.gov (United States)

    Feinstein, Douglas L; Akpa, Belinda S; Ayee, Manuela A; Boullerne, Anne I; Braun, David; Brodsky, Sergey V; Gidalevitz, David; Hauck, Zane; Kalinin, Sergey; Kowal, Kathy; Kuzmenko, Ivan; Lis, Kinga; Marangoni, Natalia; Martynowycz, Michael W; Rubinstein, Israel; van Breemen, Richard; Ware, Kyle; Weinberg, Guy

    2016-06-01

    Superwarfarins were developed following the emergence of warfarin resistance in rodents. Compared to warfarin, superwarfarins have much longer half-lives and stronger affinity to vitamin K epoxide reductase and therefore can cause death in warfarin-resistant rodents. By the mid-1970s, the superwarfarins brodifacoum and difenacoum were the most widely used rodenticides throughout the world. Unfortunately, increased use was accompanied by a rise in accidental poisonings, reaching >16,000 per year in the United States. Risk of exposure has become a concern since large quantities, up to hundreds of kilograms of rodent bait, are applied by aerial dispersion over regions with rodent infestations. Reports of intentional use of superwarfarins in civilian and military scenarios raise the specter of larger incidents or mass casualties. Unlike warfarin overdose, for which 1-2 days of treatment with vitamin K is effective, treatment of superwarfarin poisoning with vitamin K is limited by extremely high cost and can require daily treatment for a year or longer. Furthermore, superwarfarins have actions that are independent of their anticoagulant effects, including both vitamin K-dependent and -independent effects, which are not mitigated by vitamin K therapy. In this review, we summarize superwarfarin development, biology and pathophysiology, their threat as weapons, and possible therapeutic approaches. PMID:27244102

  11. Mesenchymal stem cells: Emerging mechanisms of immunomodulation and therapy

    Institute of Scientific and Technical Information of China (English)

    Justin; D; Glenn; Katharine; A; Whartenby

    2014-01-01

    Mesenchymal stem cells(MSCs) are a pleiotropic population of cells that are self-renewing and capable of differentiating into canonical cells of the mesenchyme, including adipocytes, chondrocytes, and osteocytes. They employ multi-faceted approaches to maintain bone marrow niche homeostasis and promote wound healing during injury. Biomedical research has long sought to exploit their pleiotropic properties as a basis for cell therapy for a variety of diseases and to facilitate hematopoietic stem cell establishment and stromal reconstruction in bone marrow transplantation. Early results demonstrated their usage as safe, and there was little host response to these cells. The discovery of their immunosuppressive functions ushered in a new interest in MSCs as a promising therapeutic tool to suppress inflammation and down-regulate pathogenic immune responses in graft-versus-host and autoimmune diseases such as multiple sclerosis, autoimmune diabetes, and rheumatoid arthritis. MSCs produce a large number of soluble and membrane-bound factors, some of which inhibit immune responses. However, the full range of MSC-mediated immune-modulation remains incompletely understood, as emerging reports also reveal that MSCs can adopt an immunogenic phenotype, stimulate immune cells, and yield seemingly contradictory results in experimental animal models of inflammatory disease. The present review describes the large body of literature that has been accumulated on the fascinating biology of MSCs and their complex effects on immune responses.

  12. Fluid Mechanics of the Vascular Basement Membrane in the Brain

    Science.gov (United States)

    Coloma, Mikhail; Hui, Jonathan; Chiarot, Paul; Huang, Peter; Carare, Roxana; McLeod, Kenneth; Schaffer, David

    2013-11-01

    Beta-amyloid is a normal product of brain metabolic function and is found within the interstitial fluid of the brain. Failure of the clearance of beta-amyloid from the aging brain leads to its accumulation within the walls of arteries and to Alzheimer's disease. The vascular basement membrane (VBM) within the walls of cerebral arteries surrounds the spirally arranged smooth muscle cells and represents an essential pathway for removal of beta-amyloid from the brain. This process fails with the stiffening of arterial walls associated with aging. In this study we hypothesize that the deformation of the VBM associated with arterial pulsations drives the interstitial fluid to drain in the direction opposite of the arterial blood flow. This hypothesis is theoretically investigated by modeling the VBM as a thin, coaxial, fluid-filled porous medium surrounding a periodically deforming cylindrical tube. Flow and boundary conditions required to achieve such a backward clearance are derived through a control volume analysis of mass, momentum, and energy.

  13. Emerging Anticancer Potentials of Goniothalamin and Its Molecular Mechanisms

    Directory of Open Access Journals (Sweden)

    Mohamed Ali Seyed

    2014-01-01

    Full Text Available The treatment of most cancers is still inadequate, despite tremendous steady progress in drug discovery and effective prevention. Nature is an attractive source of new therapeutics. Several medicinal plants and their biomarkers have been widely used for the treatment of cancer with less known scientific basis of their functioning. Although a wide array of plant derived active metabolites play a role in the prevention and treatment of cancer, more extensive scientific evaluation of their mechanisms is still required. Styryl-lactones are a group of secondary metabolites ubiquitous in the genus Goniothalamus that have demonstrated to possess antiproliferative activity against cancer cells. A large body of evidence suggests that this activity is associated with the induction of apoptosis in target cells. In an effort to promote further research on the genus Goniothalamus, this review offers a broad analysis of the current knowledge on Goniothalamin (GTN or 5, 6, dihydro-6-styryl-2-pyronone (C13H12O2, a natural occurring styryl-lactone. Therefore, it includes (i the source of GTN and other metabolites; (ii isolation, purification, and (iii the molecular mechanisms of actions of GTN, especially the anticancer properties, and summarizes the role of GTN which is crucial for drug design, development, and application in future for well-being of humans.

  14. Evolving the Language-Ready Brain and the Social Mechanisms that Support Language

    Science.gov (United States)

    Arbib, Michael A.

    2009-01-01

    We first review the mirror-system hypothesis on the evolution of the language-ready brain, stressing the important role of imitation and protosign in providing the scaffolding for protospeech. We then assess the role of social interaction and non-specific knowledge of language in the emergence of new sign languages in deaf communities (focusing on…

  15. Evolving the Language Ready Brain and the Social Mechanisms that Support Language

    OpenAIRE

    Arbib, Michael A.

    2009-01-01

    We first review the Mirror-System Hypothesis on the evolution of the language-ready brain, stressing the important role of imitation and protosign in providing the scaffolding for protospeech. We then assess the role of social interaction and non-specific knowledge of language in the emergence of new sign languages in deaf communities (focusing on Nicaraguan Sign Language).

  16. The mechanical activation of mTOR signaling: an emerging role for late endosome/lysosomal targeting.

    Science.gov (United States)

    Jacobs, Brittany L; Goodman, Craig A; Hornberger, Troy A

    2014-02-01

    It is well recognized that mechanical signals play a critical role in the regulation of skeletal muscle mass, and the maintenance of muscle mass is essential for mobility, disease prevention and quality of life. Furthermore, over the last 15 years it has become established that signaling through a protein kinase called the mammalian (or mechanistic) target of rapamycin (mTOR) is essential for mechanically-induced changes in protein synthesis and muscle mass, however, the mechanism(s) via which mechanical stimuli regulate mTOR signaling have not been defined. Nonetheless, advancements are being made, and an emerging body of evidence suggests that the late endosome/lysosomal (LEL) system might play a key role in this process. Therefore, the purpose of this review is to summarize this body of evidence. Specifically, we will first explain why the Ras homologue enriched in brain (Rheb) and phosphatidic acid (PA) are considered to be direct activators of mTOR signaling. We will then describe the process of endocytosis and its involvement in the formation of LEL structures, as well as the evidence which indicates that mTOR and its direct activators (Rheb and PA) are all enriched at the LEL. Finally, we will summarize the evidence that has implicated the LEL in the regulation of mTOR by various growth regulatory inputs such as amino acids, growth factors and mechanical stimuli. PMID:24162376

  17. The mechanical activation of mTOR signaling: an emerging role for late endosome/lysosomal targeting.

    Science.gov (United States)

    Jacobs, Brittany L; Goodman, Craig A; Hornberger, Troy A

    2014-02-01

    It is well recognized that mechanical signals play a critical role in the regulation of skeletal muscle mass, and the maintenance of muscle mass is essential for mobility, disease prevention and quality of life. Furthermore, over the last 15 years it has become established that signaling through a protein kinase called the mammalian (or mechanistic) target of rapamycin (mTOR) is essential for mechanically-induced changes in protein synthesis and muscle mass, however, the mechanism(s) via which mechanical stimuli regulate mTOR signaling have not been defined. Nonetheless, advancements are being made, and an emerging body of evidence suggests that the late endosome/lysosomal (LEL) system might play a key role in this process. Therefore, the purpose of this review is to summarize this body of evidence. Specifically, we will first explain why the Ras homologue enriched in brain (Rheb) and phosphatidic acid (PA) are considered to be direct activators of mTOR signaling. We will then describe the process of endocytosis and its involvement in the formation of LEL structures, as well as the evidence which indicates that mTOR and its direct activators (Rheb and PA) are all enriched at the LEL. Finally, we will summarize the evidence that has implicated the LEL in the regulation of mTOR by various growth regulatory inputs such as amino acids, growth factors and mechanical stimuli.

  18. Mechanical response of infant brain to manually inflicted shaking.

    Science.gov (United States)

    Couper, Z; Albermani, F

    2010-01-01

    Shaken baby syndrome (SBS) is a contentious issue on both biomechanical and medical fronts, primarily due to a lack of understanding of the loading-injury relationship of infant shaking and the parameters that are deterministic to its nature. In order to address this lack, a finite element (FE) representation of a three month infant head was developed to apply kinematics derived from physical testing with an anthropomorphic infant surrogate. The FE mesh was derived from a three-dimensional geometric basis, allowing for mesh size grading in regions of high importance, and future patient-specific adaptation. Cerebrospinal fluid (CSF) was represented through static pressure equilibration in combination with a locally based squeezing resistance. The results of the simulation indicate that anteroposterior shaking will lead to specific patterns of brain matter motion, increased likelihood of focal axonal injury at contact locations and deep brain structures, and a capacity for the development of subdural hematomas (SDH) due to rupture of central bridging veins.

  19. BRAIN MECHANISMS FOR REPRESENTING WHAT ANOTHER PERSON SEES

    OpenAIRE

    Heyda, Ratha D.; Green, Steven R.; Vander Wyk, Brent C.; James P Morris; Pelphrey, Kevin A.

    2010-01-01

    We used functional magnetic resonance imaging (fMRI) and a naturalistic joint attention scenario to evaluate two, alternative hypotheses concerning the social brain. The first, Content Specific Attribution hypothesis, was that core regions previously identified as being involved in social cognition also participate in representing the contents of another mind. The second, Dual Role hypothesis, was that extrastriate, category-specific visual regions respond to a visible stimulus of a specific ...

  20. Mechanisms of gender-linked ischemic brain injury

    OpenAIRE

    Liu, Mingyue; Dziennis, Suzan; Hurn, Patricia D.; Alkayed, Nabil J.

    2009-01-01

    Biological sex is an important determinant of stroke risk and outcome. Women are protected from cerebrovascular disease relative to men, an observation commonly attributed to the protective effect of female sex hormones, estrogen and progesterone. However, sex differences in brain injury persist well beyond the menopause and can be found in the pediatric population, suggesting that the effects of reproductive steroids may not completely explain sexual dimorphism in stroke. We review recent ad...

  1. Brain mechanisms for representing what another person sees.

    Science.gov (United States)

    Heyda, Ratha D; Green, Steven R; Vander Wyk, Brent C; Morris, James P; Pelphrey, Kevin A

    2010-04-01

    We used functional magnetic resonance imaging (fMRI) and a naturalistic joint attention scenario to evaluate two, alternative hypotheses concerning the social brain. The first, Content Specific Attribution hypothesis, was that core regions previously identified as being involved in social cognition also participate in representing the contents of another mind. The second, Dual Role hypothesis, was that extrastriate, category-specific visual regions respond to a visible stimulus of a specific category and to the same stimulus occluded, but when it appears to be the focus of another person's visual attention. Participants viewed category-specific stimuli (Place and Body images) to localize the extrastriate body area (EBA) and parahippocampal place area (PPA). Then, they observed a computerized character viewing each stimulus category, occluded from the participant's view. In support of the Content Specific Attribution hypothesis, whole-brain analyses revealed that viewing someone else looking at an occluded picture of a body activated brain regions previously associated with components of social cognition more than viewing someone else looking at an occluded picture of a place. Counter to the Dual Role hypothesis, functional region of interest (ROI) analyses revealed that the EBA and PPA were not clearly involved in representing what the character was seeing.

  2. A Thoracic Mechanism of Mild Traumatic Brain Injury Due to Blast Pressure Waves

    CERN Document Server

    Courtney, Amy; 10.1016/j.mehy.2008.08.015

    2008-01-01

    The mechanisms by which blast pressure waves cause mild to moderate traumatic brain injury (mTBI) are an open question. Possibilities include acceleration of the head, direct passage of the blast wave via the cranium, and propagation of the blast wave to the brain via a thoracic mechanism. The hypothesis that the blast pressure wave reaches the brain via a thoracic mechanism is considered in light of ballistic and blast pressure wave research. Ballistic pressure waves, caused by penetrating ballistic projectiles or ballistic impacts to body armor, can only reach the brain via an internal mechanism and have been shown to cause cerebral effects. Similar effects have been documented when a blast pressure wave has been applied to the whole body or focused on the thorax in animal models. While vagotomy reduces apnea and bradycardia due to ballistic or blast pressure waves, it does not eliminate neural damage in the brain, suggesting that the pressure wave directly affects the brain cells via a thoracic mechanism. ...

  3. Understanding Why Patients Return to the Emergency Department after Mild Traumatic Brain Injury within 72 Hours

    Directory of Open Access Journals (Sweden)

    Ganti, Latha

    2015-05-01

    Full Text Available Introduction: Although there are approximately 1.1 million case presentations of mild traumatic brain injury (mTBI in the emergency department (ED each year, little data is available to clinicians to identify patients who are at risk for poor outcomes, including 72-hour ED return after discharge. An understanding of patients at risk for ED return visits during the hyperacute phase following head injury would allow ED providers to develop clinical interventions that reduce its occurrence and improve outcomes. Methods: This institutional review board-approved consecutive cohort study collected injury and outcome variables on adults with the purpose of identifying positive predictors for 72-hour ED return visits in mTBI patients. Results: Of 2,787 mTBI patients, 145 (5% returned unexpectedly to the ED within 72 hours of hospital discharge. Positive predictors for ED return visits included being male (p=0.0298, being black (p=0.0456, having a lower prehospital Glasgow Coma Score (p=0.0335, suffering the injury due to a motor vehicle collision (p=0.0065, or having a bleed on head computed tomography (CT (p=0.0334. ED return visits were not significantly associated with age, fracture on head CT, or symptomology following head trauma. Patients with return visits most commonly reported post-concussion syndrome (43.1%, pain (18.7%, and recall for further clinical evaluation (14.6% as the reason for return. Of the 124 patients who returned to the ED within 72 hours, one out of five were admitted to the hospital for further care, with five requiring intensive care unit stays and four undergoing neurosurgery. Conclusion: Approximately 5% of adult patients who present to the ED for mTBI will return within 72 hours of discharge for further care. Clinicians should identify at-risk individuals during their initial visits and attempt to provide anticipatory guidance when possible. [West J Emerg Med. 2015;16(2:481–485.

  4. Neurocognition in the emergency department after a mild traumatic brain injury in youth.

    Science.gov (United States)

    Brooks, Brian L; Khan, Samna; Daya, Hussain; Mikrogianakis, Angelo; Barlow, Karen M

    2014-10-15

    Abstract The early cognitive effects from a mild traumatic brain injury (mTBI) are poorly understood in youth. The aim of this study was to examine acute neurocognitive functioning in children and adolescents who presented to the emergency department (ED) after an mTBI. Youth 8-17 years of age with an mTBI (n=77; mean age, 13.6 years; 95% confidence interval [CI], 13.0-14.2) and an orthopedic injury control (OIC) group (n=28; mean age, 13.9 years; 95% CI, 13.1-14.7) underwent a very brief computerized neurocognitive assessment (four subtests from CNS Vital Signs) in a pediatric trauma hospital ED. The mTBI and OIC groups were not significantly different on age, gender, handedness, computer familiarity, race, median family income, pain rating scales, or time from injury to assessment. There were no significant differences between the mTBI and OIC groups for accuracy on immediate memory, delayed memory, and measures of attention and executive functioning. However, the mTBI group performed significantly worse than the OIC on nearly all measures of psychomotor speed and reaction time. Further, cognitive functioning appears to worsen as more time passes since the mTBI. Neurocognitive deficits are detectable in youth with an mTBI who present to the ED, despite having a Glasgow Coma Scale score of 15/15 and normal neuroimaging (or their presentation does not warrant neuroimaging). Their profile appears to include preserved accuracy on cognitive measures, but at the expense of slower psychomotor speed and longer reaction time. PMID:24849864

  5. Pre-hospital severe traumatic brain injury – comparison of outcome in paramedic versus physician staffed emergency medical services

    OpenAIRE

    Pakkanen, Toni; Virkkunen, Ilkka; Kämäräinen, Antti; Huhtala, Heini; Silfvast, Tom; Virta, Janne; Randell, Tarja; Yli-Hankala, Arvi

    2016-01-01

    Background Traumatic brain injury (TBI) is one of the leading causes of death and permanent disability. Emergency Medical Services (EMS) personnel are often the first healthcare providers attending patients with TBI. The level of available care varies, which may have an impact on the patient’s outcome. The aim of this study was to evaluate mortality and neurological outcome of TBI patients in two regions with differently structured EMS systems. Methods A 6-year period (2005 – 2010) observatio...

  6. Mechanisms of deep brain stimulation for obsessive compulsive disorder: effects upon cells and circuits.

    Science.gov (United States)

    Bourne, Sarah K; Eckhardt, Christine A; Sheth, Sameer A; Eskandar, Emad N

    2012-01-01

    Deep brain stimulation (DBS) has emerged as a safe, effective, and reversible treatment for a number of movement disorders. This has prompted investigation of its use for other applications including psychiatric disorders. In recent years, DBS has been introduced for the treatment of obsessive compulsive disorder (OCD), which is characterized by recurrent unwanted thoughts or ideas (obsessions) and repetitive behaviors or mental acts performed in order to relieve these obsessions (compulsions). Abnormal activity in cortico-striato-thalamo-cortical (CSTC) circuits including the orbitofrontal cortex (OFC), anterior cingulate cortex (ACC), ventral striatum, and mediodorsal (MD) thalamus has been implicated in OCD. To this end a number of DBS targets including the anterior limb of the internal capsule (ALIC), ventral capsule/ventral striatum (VC/VS), ventral caudate nucleus, subthalamic nucleus (STN), and nucleus accumbens (NAc) have been investigated for the treatment of OCD. Despite its efficacy and widespread use in movement disorders, the mechanism of DBS is not fully understood, especially as it relates to psychiatric disorders. While initially thought to create a functional lesion akin to ablative procedures, it is increasingly clear that DBS may induce clinical benefit through activation of axonal fibers spanning the CSTC circuits, alteration of oscillatory activity within this network, and/or release of critical neurotransmitters. In this article we review how the use of DBS for OCD informs our understanding of both the mechanisms of DBS and the circuitry of OCD. We review the literature on DBS for OCD and discuss potential mechanisms of action at the neuronal level as well as the broader circuit level. PMID:22712007

  7. Mechanisms of deep brain stimulation for obsessive compulsive disorder: effects upon cells and circuits

    Directory of Open Access Journals (Sweden)

    Sarah Kathleen Bourne

    2012-06-01

    Full Text Available Deep brain stimulation (DBS has emerged as a safe, effective, and reversible treatment for a number of movement disorders. This has prompted investigation of its use for other applications including psychiatric disorders. In recent years, DBS has been introduced for the treatment of obsessive-compulsive disorder (OCD, which is characterized by recurrent unwanted thoughts or ideas (obsessions and repetitive behaviors or mental acts performed in order to relieve these obsessions (compulsions. Abnormal activity in cortico-striato-thalamo-cortical (CSTC circuits including the orbitofrontal cortex, anterior cingulate cortex, ventral striatum, and mediodorsal thalamus has been implicated in OCD. To this end a number of DBS targets including the anterior limb of the internal capsule, ventral capsule/ventral striatum, ventral caudate nucleus, subthalamic nucleus, nucleus accumbens, and the inferior thalamic peduncle have been investigated for the treatment of OCD. Despite its efficacy and widespread use in movement disorders, the mechanism of DBS is not fully understood, especially as it relates to psychiatric disorders. While initially thought to create a functional lesion akin to ablative procedures, it is increasingly clear that DBS may induce clinical benefit through activation of axonal fibers spanning the CSTC circuits, alteration of oscillatory activity within this network, and/or release of critical neurotransmitters. In this article we review how the use of DBS for OCD informs our understanding of both the mechanisms of DBS and the circuitry of OCD. We review the literature on DBS for OCD and discuss potential mechanisms of action at the neuronal level as well as the broader circuit level.

  8. Defective counterregulation and hypoglycemia unawareness in diabetes: Mechanisms and emerging treatments

    OpenAIRE

    Reno, Candace M.; Litvin, Marina; Clark, Amy L.; Fisher, Simon J.

    2012-01-01

    For people with diabetes, hypoglycemia remains the limiting factor in achieving glycemic control. This article reviews recent advances in how the brain senses and responds to hypoglycemia. Novel mechanisms by which people with insulin treated diabetes develop hypoglycemia unawareness and impaired counterregulatory responses are outlined. Prevention strategies for reducing the incidence of hypoglycemia are discussed

  9. Age-related hearing loss: ear and brain mechanisms.

    Science.gov (United States)

    Frisina, Robert D

    2009-07-01

    Loss of sensory function in the aged has serious consequences for economic productivity, quality of life, and healthcare costs in the billions each year. Understanding the neural and molecular bases will pave the way for biomedical interventions to prevent, slow, or reverse these conditions. This chapter summarizes new information regarding age changes in the auditory system involving both the ear (peripheral) and brain (central). A goal is to provide findings that have implications for understanding some common biological underpinnings that affect sensory systems, providing a basis for eventual interventions to improve overall sensory functioning, including the chemical senses.

  10. Emerging role of the brain in the homeostatic regulation of energy and glucose metabolism.

    Science.gov (United States)

    Roh, Eun; Song, Do Kyeong; Kim, Min-Seon

    2016-01-01

    Accumulated evidence from genetic animal models suggests that the brain, particularly the hypothalamus, has a key role in the homeostatic regulation of energy and glucose metabolism. The brain integrates multiple metabolic inputs from the periphery through nutrients, gut-derived satiety signals and adiposity-related hormones. The brain modulates various aspects of metabolism, such as food intake, energy expenditure, insulin secretion, hepatic glucose production and glucose/fatty acid metabolism in adipose tissue and skeletal muscle. Highly coordinated interactions between the brain and peripheral metabolic organs are critical for the maintenance of energy and glucose homeostasis. Defective crosstalk between the brain and peripheral organs contributes to the development of obesity and type 2 diabetes. Here we comprehensively review the above topics, discussing the main findings related to the role of the brain in the homeostatic regulation of energy and glucose metabolism. PMID:26964832

  11. 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...

  12. Skull Flexure from Blast Waves: A Mechanism for Brain Injury with Implications for Helmet Design

    Energy Technology Data Exchange (ETDEWEB)

    Moss, W C; King, M J; Blackman, E G

    2009-04-30

    Traumatic brain injury [TBI] has become a signature injury of current military conflicts, with debilitating, costly, and long-lasting effects. Although mechanisms by which head impacts cause TBI have been well-researched, the mechanisms by which blasts cause TBI are not understood. From numerical hydrodynamic simulations, we have discovered that non-lethal blasts can induce sufficient skull flexure to generate potentially damaging loads in the brain, even without a head impact. The possibility that this mechanism may contribute to TBI has implications for injury diagnosis and armor design.

  13. Is the World Local or Nonlocal? Towards an Emergent Quantum Mechanics in the 21st Century

    CERN Document Server

    Walleczek, Jan

    2016-01-01

    What defines an emergent quantum mechanics (EmQM)? Can new insight be advanced into the nature of quantum nonlocality by seeking new links between quantum and emergent phenomena as described by self-organization, complexity, or emergence theory? Could the development of a future EmQM lead to a unified, relational image of the cosmos? One key motivation for adopting the concept of emergence in relation to quantum theory concerns the persistent failure in standard physics to unify the two pillars in the foundations of physics: quantum theory and general relativity theory (GRT). The total contradiction in the foundational, metaphysical assumptions that define orthodox quantum theory versus GRT might render inter-theoretic unification impossible. On the one hand, indeterminism and non-causality define orthodox quantum mechanics, and, on the other hand, GRT is governed by causality and determinism. How could these two metaphysically-contradictory theories ever be reconciled? The present work argues that metaphysic...

  14. Management of critically ill patients receiving noninvasive and invasive mechanical ventilation in the emergency department

    OpenAIRE

    Rose, Louise

    2012-01-01

    Louise RoseLawrence S Bloomberg Faculty of Nursing, University of Toronto, Toronto, Ontario, CanadaAbstract: Patients requiring noninvasive and invasive ventilation frequently present to emergency departments, and may remain for prolonged periods due to constrained critical care services. Emergency clinicians often do not receive the same education on management of mechanical ventilation or have similar exposure to these patients as do their critical care colleagues. The aim of this review wa...

  15. Management of critically ill patients receiving noninvasive and invasive mechanical ventilation in the emergency department

    OpenAIRE

    Rose, Louise

    2012-01-01

    Patients requiring noninvasive and invasive ventilation frequently present to emergency departments, and may remain for prolonged periods due to constrained critical care services. Emergency clinicians often do not receive the same education on management of mechanical ventilation or have similar exposure to these patients as do their critical care colleagues. The aim of this review was to synthesize the evidence on management of patients requiring noninvasive and invasive ventilation in the ...

  16. Brain-to-brain coupling : a mechanism for creating and sharing a social world

    NARCIS (Netherlands)

    Hasson, Uri; Ghazanfar, Asif A.; Galantucci, Bruno; Garrod, Simon; Keysers, Christian

    2012-01-01

    Cognition materializes in an interpersonal space. The emergence of complex behaviors requires the coordination of actions among individuals according to a shared set of rules. Despite the central role of other individuals in shaping one's mind, most cognitive studies focus on processes that occur wi

  17. Brain Mechanisms for Making, Breaking, and Changing Rules

    Science.gov (United States)

    Levine, Daniel S.

    Individuals differ widely, and the same person varies over time, in their tendency to seek maximum information versus their tendency to follow the simplest heuristics. Neuroimaging studies suggest which brain regions might mediate the balance between knowledge maximization and heuristic simplification. The amygdala is more activated in individuals who use primitive heuristics, whereas two areas of the frontal lobes are more activated in individuals with a strong knowledge drive: one area involved in detecting risk or conflict, and another involved in choosing task-appropriate responses. Both of these motivations have engineering uses. There is benefit to understanding a situation at a high enough level to respond in a flexible manner when the context is complex and time allows detailed consideration. Yet simplifying heuristics can yield benefits when the context is routine or when time is limited.

  18. Mechanisms of Brain Aging Regulation by Insulin: Implications for Neurodegeneration in Late-Onset Alzheimer's Disease

    OpenAIRE

    Schuh, Artur F.; Rieder, Carlos M.; Rizzi, Liara; Chaves, Márcia; Roriz-Cruz, Matheus

    2011-01-01

    Insulin and IGF seem to be important players in modulating brain aging. Neurons share more similarities with islet cells than any other human cell type. Insulin and insulin receptors are diffusely found in the brain, especially so in the hippocampus. Caloric restriction decreases insulin resistance, and it is the only proven mechanism to expand lifespan. Conversely, insulin resistance increases with age, obesity, and sedentarism, all of which have been shown to be risk factors for late-onset ...

  19. [Metallothionein-I/II in brain injury repair mechanism and its application in forensic medicine].

    Science.gov (United States)

    Li, Dong; Li, Ru-bo; Lin, Ju-li

    2013-10-01

    Metallothionein (MT) is a kind of metal binding protein. As an important member in metallothionein family, MT-I/II regulates metabolism and detoxication of brain metal ion and scavenges free radicals. It is capable of anti-inflammatory response and anti-oxidative stress so as to protect the brain tissue. During the repair process of brain injury, the latest study showed that MT-I/II could stimulate brain anti-inflammatory factors, growth factors, neurotrophic factors and the expression of the receptor, and promote the extension of axon of neuron, which makes contribution to the regeneration of neuron and has important effect on the recovery of brain injury. Based on the findings, this article reviews the structure, expression, distribution, adjustion, function, mechanism in the repair of brain injury of MT-I/II and its application prospect in forensic medicine. It could provide a new approach for the design and manufacture of brain injury drugs as well as for age estimation of the brain injury.

  20. Unraveling the fundamental molecular mechanisms of morphological and cognitive defects in the irradiated brain.

    Science.gov (United States)

    Verheyde, Joris; Benotmane, Mohammed Abderrafi

    2007-02-01

    Prenatal radiation exposure may have serious consequences for normal brain development. Results of epidemiological studies clearly pointed towards an increased risk of mental retardation in children of the surviving women of the Hiroshima/Nagasaki atomic bombing when in utero exposure had occurred between weeks 8 and 15 of pregnancy or, at a lower extend between weeks 15 and 25. The high sensitivity of the developing brain, in comparison to the adult brain is related to its higher number of non-differentiated, dividing neural precursor cells. Exposure of the developing brain to ionizing radiation can lead to three main outcomes in the developing brain, depending on the radiation dose and the elapsed period after irradiation. A first event occurs early after irradiation and triggers disturbances in cell proliferation, migration, differentiation, and cell death. A second event involves the generation of morphological abnormalities in the developing brain, if the radiation dose is sufficient. A third event involves cognitive dysfunctions that are a direct consequence from a disturbance in regional brain formation. The latter results from exposure to low doses and is usually only observed in the later period of development. In order to understand the mechanisms of radiation-induced cognitive dysfunctions, it is important to track back the underlying changes in specific molecular pathways. In this review, we present the possible relationships within and between molecular pathways potentially involved in cognitive dysfunctions induced by ionizing radiation in the developing brain. PMID:17188364

  1. Human Brain Networks: Spiking Neuron Models, Multistability, Synchronization, Thermodynamics, Maximum Entropy Production, and Anesthetic Cascade Mechanisms

    Directory of Open Access Journals (Sweden)

    Wassim M. Haddad

    2014-07-01

    theoretical foundation for general anesthesia using the network properties of the brain. Finally, we present some key emergent properties from the fields of thermodynamics and electromagnetic field theory to qualitatively explain the underlying neuronal mechanisms of action for anesthesia and consciousness.

  2. A mechanical model predicts morphological abnormalities in the developing human brain

    Science.gov (United States)

    Budday, Silvia; Raybaud, Charles; Kuhl, Ellen

    2014-07-01

    The developing human brain remains one of the few unsolved mysteries of science. Advancements in developmental biology, neuroscience, and medical imaging have brought us closer than ever to understand brain development in health and disease. However, the precise role of mechanics throughout this process remains underestimated and poorly understood. Here we show that mechanical stretch plays a crucial role in brain development. Using the nonlinear field theories of mechanics supplemented by the theory of finite growth, we model the human brain as a living system with a morphogenetically growing outer surface and a stretch-driven growing inner core. This approach seamlessly integrates the two popular but competing hypotheses for cortical folding: axonal tension and differential growth. We calibrate our model using magnetic resonance images from very preterm neonates. Our model predicts that deviations in cortical growth and thickness induce morphological abnormalities. Using the gyrification index, the ratio between the total and exposed surface area, we demonstrate that these abnormalities agree with the classical pathologies of lissencephaly and polymicrogyria. Understanding the mechanisms of cortical folding in the developing human brain has direct implications in the diagnostics and treatment of neurological disorders, including epilepsy, schizophrenia, and autism.

  3. [Water and electrolytes disorders after brain injury: mechanism and treatment].

    Science.gov (United States)

    Audibert, G; Hoche, J; Baumann, A; Mertes, P-M

    2012-06-01

    Electrolyte disturbances are frequent after brain injuries, especially dysnatremia and dyskalemia. In neurological patients, usual clinical signs of hyponatremia are frequently confounded with clinical signs of the underlying disease. Natremia absolute value is less important than speed of onset of the trouble. Most often, hyponatremia is associated with hypotonicity and intracellular hyperhydration, which may exacerbate a cerebral edema. Distinction between inappropriate secretion of antidiuretic hormone (SIADH) and cerebral salt wasting syndrome (CSWS) may be difficult and is mainly based on assessment of patient's volemia, SIADH being associated with normal or hypervolemia and CSWS with hypovolemia. After subarachnoid haemorrhage, the most common disorder is CSWS. In this case, fluid restriction is strictly prohibited. Treatment of CSWS needs to compensate for the natriuresis and may justify the use of mineralocorticoid. It is important to avoid excessively rapid correction of hypernatremia, with a maximal speed of correction of 0.5 m mol/l/h. Serum sodium monitoring should be mandatory for the first ten postoperative days after pituitary adenoma surgery. Therapeutic barbiturate may be responsible for life threatening dyskalemia. PMID:22683162

  4. Fuel reduction at a Spanish heathland by prescribed fire and mechanical shredding: effects on seedling emergence.

    Science.gov (United States)

    Fernández, Cristina; Vega, José A; Fonturbel, Teresa

    2013-11-15

    Traditional heathland burning has declined in Spain, leading to fuel accumulation and fuel reduction treatments have become common for severe wildfire hazard reduction. These methods need to maintain the botanical composition of those shrub communities. Prescribed fire has been widely used in the past, but we need to compare mechanical fuel reduction with prescribed fire because it is easier and safer to carry out in a wide range of weather conditions. This information could be particularly useful in flammable ecosystems all over the world where traditional anthropogenic burning has declined. In this study, we compared the effects of prescribed burning and mechanical shredding on the seedling emergence and its relation to the mature vegetation in a fire-prone heathland dominated by Erica australis L. and Pterospartum tridentatum (L.) Willk., in Galicia (NW Spain). We combined a greenhouse experiment with periodic field inventories of seedling emergence. In the greenhouse study, the seedling emergence was significantly higher in the soil samples after burning (383 seedlings m(-2)) than in samples before burning (242 seedlings m(-2)). In contrast, there was no significant difference in seedling density before and after mechanical shredding (243 compared with 261 seedlings m(-2)). Also, the number of seedlings that emerged after burning was significantly higher than that emerged after mechanical shredding. The maximum temperatures at the soil organic layer surface during burning were significantly and positively related to the density of Halimium lasianthum ssp. alyssoides and P. tridentatum seedlings. In the field study, the observed seedling density was very low both after prescribed burning and mechanical shredding. There was a high degree of similarity between emerged seedlings and mature vegetation in both the treated and in the untreated soils, which was probably a consequence of the dominance of resprouting species. Some consequences for the management of

  5. The Stress and Vascular Catastrophes in Newborn Rats: Mechanisms Preceding and Accompanying the Brain Hemorrhages

    Science.gov (United States)

    Semyachkina-Glushkovskaya, Oxana; Borisova, Ekaterina; Abakumov, Maxim; Gorin, Dmitry; Avramov, Latchezar; Fedosov, Ivan; Namykin, Anton; Abdurashitov, Arkady; Serov, Alexander; Pavlov, Alexey; Zinchenko, Ekaterina; Lychagov, Vlad; Navolokin, Nikita; Shirokov, Alexander; Maslyakova, Galina; Zhu, Dan; Luo, Qingming; Chekhonin, Vladimir; Tuchin, Valery; Kurths, Jürgen

    2016-01-01

    In this study, we analyzed the time-depended scenario of stress response cascade preceding and accompanying brain hemorrhages in newborn rats using an interdisciplinary approach based on: a morphological analysis of brain tissues, coherent-domain optical technologies for visualization of the cerebral blood flow, monitoring of the cerebral oxygenation and the deformability of red blood cells (RBCs). Using a model of stress-induced brain hemorrhages (sound stress, 120 dB, 370 Hz), we studied changes in neonatal brain 2, 4, 6, 8 h after stress (the pre-hemorrhage, latent period) and 24 h after stress (the post-hemorrhage period). We found that latent period of brain hemorrhages is accompanied by gradual pathological changes in systemic, metabolic, and cellular levels of stress. The incidence of brain hemorrhages is characterized by a progression of these changes and the irreversible cell death in the brain areas involved in higher mental functions. These processes are realized via a time-depended reduction of cerebral venous blood flow and oxygenation that was accompanied by an increase in RBCs deformability. The significant depletion of the molecular layer of the prefrontal cortex and the pyramidal neurons, which are crucial for associative learning and attention, is developed as a consequence of homeostasis imbalance. Thus, stress-induced processes preceding and accompanying brain hemorrhages in neonatal period contribute to serious injuries of the brain blood circulation, cerebral metabolic activity and structural elements of cognitive function. These results are an informative platform for further studies of mechanisms underlying stress-induced brain hemorrhages during the first days of life that will improve the future generation's health. PMID:27378933

  6. Mechanisms of deep brain stimulation for obsessive compulsive disorder: effects upon cells and circuits

    OpenAIRE

    Bourne, Sarah K.; Eckhardt, Christine A.; Sheth, Sameer A.; Eskandar, Emad N.

    2012-01-01

    Deep brain stimulation (DBS) has emerged as a safe, effective, and reversible treatment for a number of movement disorders. This has prompted investigation of its use for other applications including psychiatric disorders. In recent years, DBS has been introduced for the treatment of obsessive compulsive disorder (OCD), which is characterized by recurrent unwanted thoughts or ideas (obsessions) and repetitive behaviors or mental acts performed in order to relieve these obsessions (compulsions...

  7. Mechanisms of deep brain stimulation for obsessive compulsive disorder: effects upon cells and circuits

    OpenAIRE

    Sarah Kathleen Bourne; Christine Ann Eckhardt; Sheth, Sameer A.; Eskandar, Emad N.

    2012-01-01

    Deep brain stimulation (DBS) has emerged as a safe, effective, and reversible treatment for a number of movement disorders. This has prompted investigation of its use for other applications including psychiatric disorders. In recent years, DBS has been introduced for the treatment of obsessive-compulsive disorder (OCD), which is characterized by recurrent unwanted thoughts or ideas (obsessions) and repetitive behaviors or mental acts performed in order to relieve these obsessions (compulsions...

  8. PHILOSOPHY OF MIND; THEORETICAL AND EXPERIMENTAL CONTRIBUTION TO THE EMERGING VISION OF MIND-BRAIN INTERACTION.

    OpenAIRE

    Paul Ruiz Santos

    2011-01-01

    This work aims to contribute to the discussion of mind-brain interactions from an emergentism point of view of the Philosophy of Mind, using some of the naturalized theories. Some proposed bridges between mind and brain based on experimental naturalization are neuro-psychoanalysis, mirror neurons, and psychosomatics, among others. Naturalization can be achieved by earching for the link between psychological and biological processes. This biological-based approach can be developed avoiding mp...

  9. A functional architecture of the human brain: Emerging insights from the science of emotion

    OpenAIRE

    Lindquist, Kristen A; Barrett, Lisa Feldman

    2012-01-01

    The ‘faculty psychology’ approach to the mind, which attempts to explain mental function in terms of categories that reflect modular ‘faculties’, such as emotions, cognitions, and perceptions, has dominated research into the mind and its physical correlates. In this paper, we argue that brain organization does not respect the commonsense categories belonging to the faculty psychology approach. We review recent research from the science of emotion demonstrating that the human brain contains br...

  10. Is the World Local or Nonlocal? Towards an Emergent Quantum Mechanics in the 21st Century

    Science.gov (United States)

    Walleczek, Jan; Grössing, Gerhard

    2016-03-01

    What defines an emergent quantum mechanics (EmQM)? Can new insight be advanced into the nature of quantum nonlocality by seeking new links between quantum and emergent phenomena as described by self-organization, complexity, or emergence theory? Could the development of a future EmQM lead to a unified, relational image of the cosmos? One key motivation for adopting the concept of emergence in relation to quantum theory concerns the persistent failure in standard physics to unify the two pillars in the foundations of physics: quantum theory and general relativity theory (GRT). The total contradiction in the foundational, metaphysical assumptions that define orthodox quantum theory versus GRT might render inter-theoretic unification impossible. On the one hand, indeterminism and non-causality define orthodox quantum mechanics, and, on the other hand, GRT is governed by causality and determinism. How could these two metaphysically-contradictory theories ever be reconciled? The present work argues that metaphysical contradiction necessarily implies physical contradiction. The contradictions are essentially responsible also for the measurement problem in quantum mechanics. A common foundation may be needed for overcoming the contradictions between the two foundational theories. The concept of emergence, and the development of an EmQM, might help advance a common foundation - physical and metaphysical - as required for successfull inter-theory unification.

  11. The auditory and non-auditory brain areas involved in tinnitus. An emergent property of multiple parallel overlapping subnetworks.

    Science.gov (United States)

    Vanneste, Sven; De Ridder, Dirk

    2012-01-01

    Tinnitus is the perception of a sound in the absence of an external sound source. It is characterized by sensory components such as the perceived loudness, the lateralization, the tinnitus type (pure tone, noise-like) and associated emotional components, such as distress and mood changes. Source localization of quantitative electroencephalography (qEEG) data demonstrate the involvement of auditory brain areas as well as several non-auditory brain areas such as the anterior cingulate cortex (dorsal and subgenual), auditory cortex (primary and secondary), dorsal lateral prefrontal cortex, insula, supplementary motor area, orbitofrontal cortex (including the inferior frontal gyrus), parahippocampus, posterior cingulate cortex and the precuneus, in different aspects of tinnitus. Explaining these non-auditory brain areas as constituents of separable subnetworks, each reflecting a specific aspect of the tinnitus percept increases the explanatory power of the non-auditory brain areas involvement in tinnitus. Thus, the unified percept of tinnitus can be considered an emergent property of multiple parallel dynamically changing and partially overlapping subnetworks, each with a specific spontaneous oscillatory pattern and functional connectivity signature. PMID:22586375

  12. Brain mechanisms underlying sensation-seeking in humans

    OpenAIRE

    Norbury, A. E.

    2015-01-01

    Sensation-seeking is a personality trait concerned with motivation for intense and unusual sensory experiences, that has been identified as risk factor for a variety of psychopathologies with high social cost; in particular gambling and substance addictions. It has previously proved difficult to tease out neural mechanisms underlying sensation-seeking in humans, due to a lack of cognitive-behavioural paradigms probing sensation-seeking-like behaviour in the lab. The first aim of this thesis w...

  13. Knowing When to Stop: The Brain Mechanisms of Chasing Losses

    DEFF Research Database (Denmark)

    Campbell-Meiklejohn, Daniel; Woolrich, Mark; Passingham, Dick;

    2008-01-01

    adult participants decided to chase losses or decided to quit gambling to prevent further losses.ResultsChasing losses was associated with increased activity in cortical areas linked to incentive-motivation and an expectation of reward. By contrast, quitting was associated with decreased activity...... in pathological gambling might involve a failure to appropriately balance activity within neural systems coding conflicting motivational states. Similar mechanisms might underlie the loss-of-control over appetitive behaviors in other impulse control disorders....

  14. Brain Mechanisms Supporting Modulation of Pain by Mindfulness Meditation

    OpenAIRE

    Zeidan, F.; Martucci, K.T.; Kraft, R.A.; Gordon, N. S.; McHaffie, J.G.; Coghill, R.C.

    2011-01-01

    The subjective experience of one’s environment is constructed by interactions among sensory, cognitive, and affective processes. For centuries, meditation has been thought to influence such processes by enabling a non-evaluative representation of sensory events. To better understand how meditation influences the sensory experience, we employed arterial spin labeling (ASL) functional magnetic resonance imaging to assess the neural mechanisms by which mindfulness meditation influences pain in h...

  15. Mechanism Interpretation of the Biological Brain Cooling and Its Inspiration on Bionic Engineering

    Institute of Scientific and Technical Information of China (English)

    Xu Xue; Jing Liu

    2011-01-01

    The brain is one of the most important organs in a biological body which can only work in a relatively stable temperature range. However, many environmental factors in biosphere would cause cerebral temperature fluctuations. To sustain and regulate the brain temperature, many mechanisms of biological brain cooling have been evolved, including Selective Brain Cooling (SBC), cooling through surface water evaporation, respiration, behavior response and using special anatomical appendages. This article is dedicated to present a summarization and systematic interpretation on brain cooling strategies developed in animals by classifying and comparatively analyzing each typical biological brain cooling mechanism from the perspective of bio-heat transfer. Meanwhile, inspirations from such cooling in nature were proposed for developing advanced bionic engineering technologies especially with two focuses on therapeutic hypothermia and computer chip cooling areas. It is expected that many innovations can be achieved along this way to find out new cooling methodologies for a wide variety of industrial applications which will be highly efficient, energy saving, flexible or even intelligent.

  16. Working toward exposure thresholds for blast-induced traumatic brain injury: thoracic and acceleration mechanisms

    CERN Document Server

    Courtney, Michael; 10.1016/j.neuroimage.2010.05.025

    2011-01-01

    Research in blast-induced lung injury resulted in exposure thresholds that are useful in understanding and protecting humans from such injury. Because traumatic brain injury (TBI) due to blast exposure has become a prominent medical and military problem, similar thresholds should be identified that can put available research results in context and guide future research toward protecting warfighters as well as diagnosis and treatment. At least three mechanical mechanisms by which the blast wave may result in brain injury have been proposed - a thoracic mechanism, head acceleration and direct cranial transmission. These mechanisms need not be mutually exclusive. In this study, likely regions of interest for the first two mechanisms based on blast characteristics (positive pulse duration and peak effective overpressure) are developed using available data from blast experiments and related studies, including behind-armor blunt trauma and ballistic pressure wave studies. These related studies are appropriate to in...

  17. How neurons make meaning: brain mechanisms for embodied and abstract-symbolic semantics.

    Science.gov (United States)

    Pulvermüller, Friedemann

    2013-09-01

    How brain structures and neuronal circuits mechanistically underpin symbolic meaning has recently been elucidated by neuroimaging, neuropsychological, and neurocomputational research. Modality-specific 'embodied' mechanisms anchored in sensorimotor systems appear to be relevant, as are 'disembodied' mechanisms in multimodal areas. In this paper, four semantic mechanisms are proposed and spelt out at the level of neuronal circuits: referential semantics, which establishes links between symbols and the objects and actions they are used to speak about; combinatorial semantics, which enables the learning of symbolic meaning from context; emotional-affective semantics, which establishes links between signs and internal states of the body; and abstraction mechanisms for generalizing over a range of instances of semantic meaning. Referential, combinatorial, emotional-affective, and abstract semantics are complementary mechanisms, each necessary for processing meaning in mind and brain. PMID:23932069

  18. How neurons make meaning: brain mechanisms for embodied and abstract-symbolic semantics.

    Science.gov (United States)

    Pulvermüller, Friedemann

    2013-09-01

    How brain structures and neuronal circuits mechanistically underpin symbolic meaning has recently been elucidated by neuroimaging, neuropsychological, and neurocomputational research. Modality-specific 'embodied' mechanisms anchored in sensorimotor systems appear to be relevant, as are 'disembodied' mechanisms in multimodal areas. In this paper, four semantic mechanisms are proposed and spelt out at the level of neuronal circuits: referential semantics, which establishes links between symbols and the objects and actions they are used to speak about; combinatorial semantics, which enables the learning of symbolic meaning from context; emotional-affective semantics, which establishes links between signs and internal states of the body; and abstraction mechanisms for generalizing over a range of instances of semantic meaning. Referential, combinatorial, emotional-affective, and abstract semantics are complementary mechanisms, each necessary for processing meaning in mind and brain.

  19. Emerging interpretations of quantum mechanics and recent progress in quantum measurement

    Science.gov (United States)

    Clarke, M. L.

    2014-01-01

    The focus of this paper is to provide a brief discussion on the quantum measurement process, by reviewing select examples highlighting recent progress towards its understanding. The areas explored include an outline of the measurement problem, the standard interpretation of quantum mechanics, quantum to classical transition, types of measurement (including weak and projective measurements) and newly emerging interpretations of quantum mechanics (decoherence theory, objective reality, quantum Darwinism and quantum Bayesianism).

  20. Set up national emergency-response mechanism to scientifically cope with natural disasters

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The establishment of a national emergency management mechanism will enable China to promptly respond to and scientifically cope with natural disasters. This is a lesson we draw from the 2008 winter storms," notes a panel of the CAS Academic Divisions, China's top advisory body in science and technology in a recent proposal forwarded to State policy-makers.

  1. Cognitive Interventions in Alzheimer’s and Parkinson’s Diseases: Emerging Mechanisms and Role of Imaging

    Science.gov (United States)

    Vemuri, Prashanthi; Fields, Julie; Peter, Jessica; Klöppel, Stefan

    2016-01-01

    Purpose of review There has been recent debate about the lack of compelling scientific evidence on the efficacy of cognitive interventions. The goal of this paper is to review the current state of cognitive interventions in Alzheimer’s disease (AD) and Parkinson’s disease (PD), present emerging mechanisms, and discuss the role of imaging in designing effective intervention strategies. Recent findings Cognitive interventions appear to be promising in AD and PD. Though feasibility has been shown in mild cognitive impairment, early AD, mild to moderate PD; studies to investigate long term efficacy and mechanisms underlying these interventions are still needed. Summary There is a need to conduct scientifically rigorous studies to validate the efficacy of cognitive intervention trials. Future studies will greatly benefit from including longitudinal imaging in their study design. Imaging can be used to demonstrate the efficacy and mechanisms by measuring brain changes over the intervention period. Imaging can also be used to determine biological and disease-related factors that may influence the treatment response i.e. the effect modifiers. Consideration of effect modifiers will allow us to measure the treatment response in biomarkers and cognition with greater sensitivity and also aid in designing trials that will lead to better patient outcomes. PMID:27213773

  2. Emotional attention for erotic stimuli: Cognitive and brain mechanisms.

    Science.gov (United States)

    Sennwald, Vanessa; Pool, Eva; Brosch, Tobias; Delplanque, Sylvain; Bianchi-Demicheli, Francesco; Sander, David

    2016-06-01

    It has long been posited that among emotional stimuli, only negative threatening information modulates early shifts of attention. However, in the last few decades there has been an increase in research showing that attention is also involuntarily oriented toward positive rewarding stimuli such as babies, food, and erotic information. Because reproduction-related stimuli have some of the largest effects among positive stimuli on emotional attention, the present work reviews recent literature and proposes that the cognitive and cerebral mechanisms underlying the involuntarily attentional orientation toward threat-related information are also sensitive to erotic information. More specifically, the recent research suggests that both types of information involuntarily orient attention due to their concern relevance and that the amygdala plays an important role in detecting concern-relevant stimuli, thereby enhancing perceptual processing and influencing emotional attentional processes. PMID:26179894

  3. Atypical Brain Mechanisms of Prediction According to Uncertainty in Autism.

    Science.gov (United States)

    Thillay, Alix; Lemaire, Mathieu; Roux, Sylvie; Houy-Durand, Emmanuelle; Barthélémy, Catherine; Knight, Robert T; Bidet-Caulet, Aurélie; Bonnet-Brilhault, Frédérique

    2016-01-01

    Resistance to change is often reported in autism and may arise from an inability to predict events in uncertain contexts. Using EEG recorded in 12 adults with autism and age-matched controls performing a visual target detection task, we characterized the influence of a certain context (targets preceded by a predictive sequence of three distinct stimuli) or an uncertain context (random targets) on behavior and electrophysiological markers of predictive processing. During an uncertain context, adults with autism were faster than controls to detect targets. They also had an enhancement in CNV amplitude preceding all random stimuli-indexing enhanced preparatory mechanisms, and an earlier N2 to targets-reflecting faster information processing-compared to controls. During a certain context, both controls and adults with autism presented an increase in P3 amplitude to predictive stimuli-indexing information encoding of the predictive sequence, an enhancement in CNV amplitude preceding predictable targets-corresponding to the deployment of preparatory mechanisms, and an earlier P3 to predictable targets-reflecting efficient prediction building and implementation. These results suggest an efficient extraction of predictive information to generate predictions in both controls and adults with autism during a certain context. However, adults with autism displayed a failure to decrease mu power during motor preparation accompanied by a reduced benefit in reaction times to predictable targets. The data reveal that patients with autism over-anticipate stimuli occurring in an uncertain context, in accord with their sense of being overwhelmed by incoming information. These results suggest that adults with autism cannot flexibly modulate cortical activity according to changing levels of uncertainty. PMID:27458337

  4. Circulating endothelial progenitor cells in traumatic brain injury: an emerging therapeutic target?

    Institute of Scientific and Technical Information of China (English)

    WEI Hui-jie; JIANG Rong-cai; LIU Li; ZHANG Jian-ning

    2010-01-01

    Traumatic brain injury (TBI) is a major cause ofmortality and morbidity in the world. Recent clinical investigations and basic researches suggest that strategies to improve angiogenesis following TBI may provide promising opportunities to improve clinical outcomes and brain functional recovery. More and more evidences show that circulating endothelial progenitor cells (EPCs), which have been identified in the peripheral blood, may play an important role in the pathologic and physiological angiogenesis in adults. Moreover, impressive data demonstrate that EPCs are mobilized from bone marrow to blood circulation in response to traumatic or inflammatory stimulations.In this review, we discussed the role of EPCs in the repair of brain injury and the possible therapeutic implication for functional recovery of TBl in the future.

  5. Brain Mechanisms Underlying Urge Incontinence and its Response to Pelvic Floor Muscle Training

    Science.gov (United States)

    Griffiths, Derek; Clarkson, Becky; Tadic, Stasa D.; Resnick, Neil M.

    2016-01-01

    Purpose Urge urinary incontinence is a major problem, especially in the elderly, and to our knowledge the underlying mechanisms of disease and therapy are unknown. We used biofeedback assisted pelvic floor muscle training and functional brain imaging (functional magnetic resonance imaging) to investigate cerebral mechanisms, aiming to improve the understanding of brain-bladder control and therapy. Materials and Methods Before receiving biofeedback assisted pelvic floor muscle training functionally intact, older community dwelling women with urge urinary incontinence as well as normal controls underwent comprehensive clinical and bladder diary evaluation, urodynamic testing and brain functional magnetic resonance imaging. Evaluation was repeated after pelvic floor muscle training in those with urge urinary incontinence. Functional magnetic resonance imaging was done to determine the brain reaction to rapid bladder filling with urgency. Results Of 65 subjects with urge urinary incontinence 28 responded to biofeedback assisted pelvic floor muscle training with 50% or greater improvement of urge urinary incontinence frequency on diary. However, responders and nonresponders displayed 2 patterns of brain reaction. In pattern 1 in responders before pelvic floor muscle training the dorsal anterior cingulate cortex and the adjacent supplementary motor area were activated as well as the insula. After the training dorsal anterior cingulate cortex/supplementary motor area activation diminished and there was a trend toward medial prefrontal cortex deactivation. In pattern 2 in nonresponders before pelvic floor muscle training the medial prefrontal cortex was deactivated, which changed little after the training. Conclusions In older women with urge urinary incontinence there appears to be 2 patterns of brain reaction to bladder filling and they seem to predict the response and nonresponse to biofeedback assisted pelvic floor muscle training. Moreover, decreased cingulate

  6. Skull Flexure from Blast Waves: A New Mechanism for Brain Injury with Implications for Helmet Design

    CERN Document Server

    Moss, William C; Blackman, Eric G

    2008-01-01

    Traumatic brain injury [TBI] has become the signature injury of current military conflicts. The debilitating effects of TBI on society are long-lasting and costly. Although the mechanisms by which impacts cause TBI have been well researched, the mechanisms by which blasts cause TBI are not understood. Various mechanisms, including impacts caused by the blast, have been investigated, but blast-induced deformation of the skull has been neglected. Through the use of hydrodynamical numerical simulations, we have discovered that non-lethal blasts can induce sufficient flexure of the skull to generate potentially damaging loads in the brain, even if no impact occurs. This mechanism has implications for the diagnosis of TBI in soldiers and the design of protective equipment such as helmets.

  7. Action and Language Mechanisms in the Brain: Data, Models and Neuroinformatics

    DEFF Research Database (Denmark)

    Arbib, Michael A.; Bonaiuto, James J.; Bornkessel-Schlesewsky, Ina;

    2014-01-01

    We assess the challenges of studying action and language mechanisms in the brain, both singly and in relation to each other to provide a novel perspective on neuroinformatics, integrating the development of databases for encoding - separately or together - neurocomputational models and empirical ...

  8. Action and Language Mechanisms in the Brain: Data, Models and Neuroinformatics

    OpenAIRE

    Arbib, Michael A.; Bonaiuto, James J.; Bornkessel-Schlesewsky, Ina; Kemmerer, David; MacWhinney, Brian; Nielsen, Finn Årup; Oztop, Erhan

    2014-01-01

    We assess the challenges of studying action and language mechanisms in the brain, both singly and in relation to each other to provide a novel perspective on neuroinformatics, integrating the development of databases for encoding – separately or together – neurocomputational models and empirical data that serve systems and cognitive neuroscience.

  9. Action and language mechanisms in the brain: data, models and neuroinformatics.

    Science.gov (United States)

    Arbib, Michael A; Bonaiuto, James J; Bornkessel-Schlesewsky, Ina; Kemmerer, David; MacWhinney, Brian; Nielsen, Finn Årup; Oztop, Erhan

    2014-01-01

    We assess the challenges of studying action and language mechanisms in the brain, both singly and in relation to each other to provide a novel perspective on neuroinformatics, integrating the development of databases for encoding – separately or together – neurocomputational models and empirical data that serve systems and cognitive neuroscience. PMID:24234916

  10. Research progress in mechanism of traumatic brain injury affecting speed of fracture healing

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xiao-gang; ZHAO Guang-feng; MA Yue-feng; JIANG Guan-yu

    2007-01-01

    @@ In patients who have sustained traumatic brain injury with associated extremity fracture, there is often a clinical perception that the rate of new bone formation around the fracture site increases. 1 An overgrowth of callus is observed and ectopic ossification even occurs in the muscle,2 but the mechanism remains unclear.

  11. Mindfulness meditation-related pain relief: Evidence for unique brain mechanisms in the regulation of pain

    OpenAIRE

    Zeidan, F.; Grant, J.A.; Brown, C. A.; McHaffie, J.G.; Coghill, R.C.

    2012-01-01

    The cognitive modulation of pain is influenced by a number of factors ranging from attention, beliefs, conditioning, expectations, mood, and the regulation of emotional responses to noxious sensory events. Recently, mindfulness meditation has been found attenuate pain through some of these mechanisms including enhanced cognitive and emotional control, as well as altering the contextual evaluation of sensory events. This review discusses the brain mechanisms involved in mindfulness meditation-...

  12. Encoding of mechanical nociception differs in the adult and infant brain.

    Science.gov (United States)

    Fabrizi, Lorenzo; Verriotis, Madeleine; Williams, Gemma; Lee, Amy; Meek, Judith; Olhede, Sofia; Fitzgerald, Maria

    2016-01-01

    Newborn human infants display robust pain behaviour and specific cortical activity following noxious skin stimulation, but it is not known whether brain processing of nociceptive information differs in infants and adults. Imaging studies have emphasised the overlap between infant and adult brain connectome architecture, but electrophysiological analysis of infant brain nociceptive networks can provide further understanding of the functional postnatal development of pain perception. Here we hypothesise that the human infant brain encodes noxious information with different neuronal patterns compared to adults. To test this we compared EEG responses to the same time-locked noxious skin lance in infants aged 0-19 days (n = 18, clinically required) and adults aged 23-48 years (n = 21). Time-frequency analysis revealed that while some features of adult nociceptive network activity are present in infants at longer latencies, including beta-gamma oscillations, infants display a distinct, long latency, noxious evoked 18-fold energy increase in the fast delta band (2-4 Hz) that is absent in adults. The differences in activity between infants and adults have a widespread topographic distribution across the brain. These data support our hypothesis and indicate important postnatal changes in the encoding of mechanical pain in the human brain. PMID:27345331

  13. Infants' Emerging Sensitivity to Emotional Body Expressions: Insights from Asymmetrical Frontal Brain Activity

    Science.gov (United States)

    Missana, Manuela; Grossmann, Tobias

    2015-01-01

    Sensitive responding to others' emotional body expressions is an essential social skill in humans. Using event-related brain potentials, it has recently been shown that the ability to discriminate between emotional body expressions develops between 4 and 8 months of age. However, it is not clear whether the perception of emotional body…

  14. Windows on the brain: the emerging role of atlases and databases in neuroscience

    Science.gov (United States)

    Van Essen, David C.; VanEssen, D. C. (Principal Investigator)

    2002-01-01

    Brain atlases and associated databases have great potential as gateways for navigating, accessing, and visualizing a wide range of neuroscientific data. Recent progress towards realizing this potential includes the establishment of probabilistic atlases, surface-based atlases and associated databases, combined with improvements in visualization capabilities and internet access.

  15. The Third Annual Deep Brain Stimulation Think Tank: A Review of Emerging Issues and Technologies

    OpenAIRE

    P. Justin eRossi; Aysegul eGunduz; Jack eJudy; Linda eWilson; Andre eMachado; James J Giordano; W. Jeff eElias; Alterman, Ron L.; Rossi, Marvin A.; Butson, Christopher L.; Fox, Michael D.; McIntyre, Cameron C.; Nader ePouratian; Swann, Nicole C.; Coralie ede Hemptinne

    2016-01-01

    This review summarizes the most contemporary clinical, electrophysiological, imaging, and computational work on DBS for the treatment of neurological and neuropsychiatric disease. Significant innovations of the past year are emphasized; these advances were presented at the 3rd Annual Deep Brain Stimulation Think Tank. The Think Tank’s contributors represent a unique multidisciplinary ensemble of expert neurologists, neurosurgeons, neuropsychologists, psychiatrists, scientists, engineers, and ...

  16. Plausible mechanisms for brain structural and size changes in human evolution.

    Science.gov (United States)

    Blazek, Vladimir; Brùzek, Jaroslav; Casanova, Manuel F

    2011-09-01

    Encephalization has many contexts and implications. On one hand, it is concerned with the transformation of eating habits, social relationships and communication, cognitive skills and the mind. Along with the increase in brain size on the other hand, encephalization is connected with the creation of more complex brain structures, namely in the cerebral cortex. It is imperative to inquire into the mechanisms which are linked with brain growth and to find out which of these mechanisms allow it and determine it. There exist a number of theories for understanding human brain evolution which originate from neurological sciences. These theories are the concept of radial units, minicolumns, mirror neurons, and neurocognitive networks. Over the course of evolution, it is evident that a whole range of changes have taken place in regards to heredity. These changes include new mutations of genes in the microcephalin complex, gene duplications, gene co-expression, and genomic imprinting. This complex study of the growth and reorganization of the brain and the functioning of hereditary factors and their external influences creates an opportunity to consider the implications of cultural evolution and cognitive faculties.

  17. Brain-Gut Interactions in Inflammatory Bowel Disease: Mechanisms of Anorexia in Animal Models of Experimental Colitis

    OpenAIRE

    Weingarten, Harvey P

    1996-01-01

    Physiological processes within the bowel are influenced constantly by signals from other organs, primarily the brain. The mechanisms by which inflammation of the gastrointestinal tract results in anorexia are unknown. Understanding how the inflammation-related signals in the periphery are communicated to the central nervous system and activate cytokine production in the brain remains an enormous challenge. Elucidation of these gut-brain communication mechanisms is essential to the development...

  18. Transport and regulation mechanism of the colloidal gold liposomes in the brain microvascular endothelial cells

    Institute of Scientific and Technical Information of China (English)

    WANG Lipeng; CHANG Yanzhong

    2015-01-01

    Objective:Blood-brain barrier is the key barrier of brain in the innate immune. It can prevent the harmful substances from the blood into the brain. In order to keep the brain in a relatively stable environment and maintain the normal function of the nervous system, it can also pump harmful substances or excess substances outside the brain selectively. Among them, brain microvascular endothelial cell tissue is a key part in the blood-brain barrier's function. The number of the patients with central nervous system ( CNS) diseases increased year by year. The therapeutic drug is usually inhibited by the blood-brain barrier and is difficult to work. Therefore, how to modify the drug and to make it easier to cross the blood brain barrier is the key point to cure CNS. At present, more than 95% research focus only on how nano drugs can enter the cell, the way and efficiency to enter the cell and the research of effect of nano drug etc. For the process of drug carrier in endocytosis, intracellular transport and release and regulation of research are rarely reported. Clathrin and P-glycoprotein are related protein in endo-cytosis and exocytosis with nano drug. Clathrin is located on the plasma membrane. It participates in endocytosis of some nutrients, and maybe the entry into the cell of some drugs. P-glycoprotein is located in the membrane of cer-ebral capillary endothelial cells. It can efflux drugs relying on ATP. Although there is a certain understanding of the cell in the inner swallow and efflux. But the process of the liposome drug is not clear. To solve the above prob-lems, using colloidal gold liposome nano materials to trace liposome's transport and regulation mechanism in brain microvascular endothelial cells, and study endocytosis, release, distribution and regulation mechanism of nano lipo-somes in brain microvascular. The solution of this problem can guide to construct reasonable drug carrier, and look forward to clarifing the molecular basis and mechanism of

  19. The mechanisms of regional branching: An investigation of the emerging fuel cell industry

    DEFF Research Database (Denmark)

    Tanner, Anne Nygaard

    The growth of evolutionary thinking in economic geography has brought about the proposition that new industries are place dependent and tend to develop in regions where the pre-existing industry is technologically related to the knowledge base of the new industry, a phenomena that is termed...... of the emerging fuel cell (FC) industry and the degree to which the underlying logic of these mechanisms is technologically related. It is concluded that the actors currently dominating the emerging FC industry are either large incumbent multinational enterprises (MNEs) or smaller dedicated FC system developers...... that are related to the core scientific principle of the FC. Hence, the findings only partly corroborate the thesis of technological relatedness as an underlying logic for regional branching in the case of an emerging industry, suggesting the need to look further into how agency and supportive organizations...

  20. Pain in chronic pancreatitis: a salutogenic mechanism or a maladaptive brain response?

    Science.gov (United States)

    Fregni, Felipe; Pascual-Leone, Alvaro; Freedman, Steven D

    2007-01-01

    Pain in chronic pancreatitis is frequently refractory to medical and even surgical treatment. This refractoriness leads us to believe that a pancreas-independent, brain-mediated mechanism must be responsible. If so, several scenarios are worth considering. First, chronic pain could be the consequence of undesirable neuroplastic changes, by which pathology becomes established and causes disability. Alternatively, pain may be linked to the salutogenic (from salutogenesis, the Latin word for health and well-being) central nervous system response (we defined 'salutogenic response' as the specific modulation of the immune system induced by brain activity changes) to promote healing of the injured viscera. If so, chronic pain could index the ongoing nervous system attempt to promote healing. In this review, we discuss (1) the mechanisms of pain in chronic pancreatitis; (2) potential brain-related salutogenic mechanisms, and (3) the potential relationship of these two factors to the disease status. Furthermore, we consider these aspects in light of a new approach to treat visceral pain: transcranial magnetic stimulation, a noninvasive method of brain stimulation. PMID:17898531

  1. Skull flexure from blast waves: a mechanism for brain injury with implications for helmet design

    Energy Technology Data Exchange (ETDEWEB)

    Moss, W C; King, M J; Blackman, E G

    2009-04-14

    Traumatic brain injury [TBI] has become a signature injury of current military conflicts. The debilitating effects of TBI are long-lasting and costly. Although the mechanisms by which impacts cause TBI have been well researched, the mechanisms by which blasts cause TBI are not understood. Various possibilities have been investigated, but blast-induced deformation of the skull has been neglected. From numerical hydrodynamic simulations, we have discovered that nonlethal blasts can induce sufficient flexure of the skull to generate potentially damaging loads in the brain, even if no impact occurs. The possibility that this mechanism may contribute to TBI has implications for the diagnosis of soldiers and the design of protective equipment such as helmets.

  2. The Acute Inflammatory Response in Trauma / Hemorrhage and Traumatic Brain Injury: Current State and Emerging Prospects

    OpenAIRE

    R, Namas; A, Ghuma; L, Hermus; R, Zamora; DO Okonkwo; TR, Billiar; Y, Vodovotz

    2009-01-01

    Traumatic injury/hemorrhagic shock (T/HS) elicits an acute inflammatory response that may result in death. Inflammation describes a coordinated series of molecular, cellular, tissue, organ, and systemic responses that drive the pathology of various diseases including T/HS and traumatic brain injury (TBI). Inflammation is a finely tuned, dynamic, highly-regulated process that is not inherently detrimental, but rather required for immune surveillance, optimal post-injury tissue repair, and rege...

  3. ‘Your Brain on Art’: Emergent cortical dynamics during aesthetic experiences

    Directory of Open Access Journals (Sweden)

    Kimberly eKontson

    2015-11-01

    Full Text Available The brain response to conceptual art was studied with mobile electroencephalography (EEG to examine the neural basis of aesthetic experiences. In contrast to most studies of perceptual phenomena, participants were moving and thinking freely as they viewed the exhibit The Boundary of Life is Quietly Crossed by Dario Robleto at the Menil Collection-Houston. The brain activity of over 400 subjects was recorded using dry-electrode and one reference gel-based EEG systems over a period of 3 months. Here, we report initial findings based on the reference system. EEG segments corresponding to each art piece were grouped into one of three classes (complex, moderate, and baseline based on analysis of a digital image of each piece. Time, frequency, and wavelet features extracted from EEG were used to classify patterns associated with viewing art, and ranked based on their relevance for classification. The maximum classification accuracy was 55% (chance = 33% with delta and gamma features the most relevant for classification. Functional analysis revealed a significant increase in connection strength in localized brain networks while subjects viewed the most aesthetically pleasing art compared to viewing a blank wall. The direction of signal flow showed early recruitment of broad posterior areas followed by focal anterior activation. Significant differences in the strength of connections were also observed across age and gender. This work provides evidence that EEG, deployed on freely behaving subjects, can detect selective signal flow in neural networks, identify significant differences between subject groups, and report with greater-than-chance accuracy the complexity of a subject’s visual percept of aesthetically pleasing art. Our approach, which allows acquisition of neural activity ‘in action and context’, could lead to understanding of how the brain integrates sensory input and its ongoing internal state to produce the phenomenon which we term

  4. Development traumatic brain injury computer user interface for disaster area in Indonesia supported by emergency broadband access network.

    Science.gov (United States)

    Sutiono, Agung Budi; Suwa, Hirohiko; Ohta, Toshizumi; Arifin, Muh Zafrullah; Kitamura, Yohei; Yoshida, Kazunari; Merdika, Daduk; Qiantori, Andri; Iskandar

    2012-12-01

    Disasters bring consequences of negative impacts on the environment and human life. One of the common cause of critical condition is traumatic brain injury (TBI), namely, epidural (EDH) and subdural hematoma (SDH), due to downfall hard things during earthquake. We proposed and analyzed the user response, namely neurosurgeon, general doctor/surgeon and nurse when they interacted with TBI computer interface. The communication systems was supported by TBI web based applications using emergency broadband access network with tethered balloon and simulated in the field trial to evaluate the coverage area. The interface consisted of demography data and multi tabs for anamnesis, treatment, follow up and teleconference interfaces. The interface allows neurosurgeon, surgeon/general doctors and nurses to entry the EDH and SDH patient's data during referring them on the emergency simulation and evaluated based on time needs and their understanding. The average time needed was obtained after simulated by Lenovo T500 notebook using mouse; 8-10 min for neurosurgeons, 12-15 min for surgeons/general doctors and 15-19 min for nurses. By using Think Pad X201 Tablet, the time needed for entry data was 5-7 min for neurosurgeon, 7-10 min for surgeons/general doctors and 12-16 min for nurses. We observed that the time difference was depending on the computer type and user literacy qualification as well as their understanding on traumatic brain injury, particularly for the nurses. In conclusion, there are five data classification for simply TBI GUI, namely, 1) demography, 2) specific anamnesis for EDH and SDH, 3) treatment action and medicine of TBI, 4) follow up data display and 5) teleneurosurgery for streaming video consultation. The type of computer, particularly tablet PC was more convenient and faster for entry data, compare to that computer mouse touched pad. Emergency broadband access network using tethered balloon is possible to be employed to cover the communications systems in

  5. Strength analysis and optimization of welding robot mechanism in emergency stop state

    Directory of Open Access Journals (Sweden)

    Zdeněk Poruba

    2016-03-01

    Full Text Available The contribution deals with the strength analysis and optimization of the welding robot mechanism in emergency stop state. The common operational positioning of the welding robot is characterized by smooth course of speeds in the time. The resulting load does not differ significantly from the static loading. However the safety requirements given by the norm require the ability of emergency stop function. Since the course of speed in time is rather steep the higher values of acceleration and thus higher excitation force is expected. The dynamical simulation performed describes the response of the robot mechanism in the form of stress course in time, quantifies the peak values of the stress caused by the dynamical component of loading and highlights the potential risks associated with this phenomenon.

  6. Emergence and resilience of cooperation in the spatial Prisoner's Dilemma via a reward mechanism

    CERN Document Server

    Jimenez, Raul; Cuesta, Jose A; Sanchez, Angel

    2007-01-01

    We study the problem of the emergence of cooperation in the spatial Prisoner's Dilemma. The pioneering work by Nowak and May showed that large initial populations of cooperators can survive and sustain cooperation in a square lattice with imitate-the-best evolutionary dynamics. We revisit this problem in a cost-benefit formulation suitable for a number of biological applications. We show that if a fixed-amount reward is established for cooperators to share, a single cooperator can invade a population of defectors and form structures that are resilient to re-invasion even if the reward mechanism is turned off. We discuss analytically the case of the invasion by a single cooperator and present agent-based simulations for small initial fractions of cooperators. Large cooperation levels, in the sustainability range, are found. In the conclusions we discuss possible applications of this model as well as its connections with other mechanisms proposed to promote the emergence of cooperation.

  7. Impairment of interrelated iron- and copper homeostatic mechanisms in brain contributes to the pathogenesis of neurodegenerative disorders

    DEFF Research Database (Denmark)

    Skjørringe, Tina; Møller, Lisbeth Birk; Moos, Torben

    2012-01-01

    is strictly regulated, and concordantly protective barriers, i.e., the blood-brain barrier (BBB) and the blood-cerebrospinal fluid (CSF) barrier (BCB) have evolved to separate the brain environment from the circulation. The uptake mechanisms of the two metals interact. Both iron deficiency and overload lead......Iron and copper are important co-factors for a number of enzymes in the brain, including enzymes involved in neurotransmitter synthesis and myelin formation. Both shortage and an excess of iron or copper will affect the brain. The transport of iron and copper into the brain from the circulation...... to altered copper homeostasis in the brain. Similarly, changes in dietary copper affect the brain iron homeostasis. Moreover, the uptake routes of iron and copper overlap each other which affect the interplay between the concentrations of the two metals in the brain. The divalent metal transporter-1 (DMT1...

  8. Effect of dexmedetomidine on mechanical pain threshold and emergence agitation after laparoscopic myomectomy

    Institute of Scientific and Technical Information of China (English)

    Tao Qin; Xiao-Mei Liu

    2016-01-01

    Objective:To study the effect of dexmedetomidine on mechanical pain threshold and emergence agitation after laparoscopic myomectomy.Methods:Random number table was used to divide 82 cases of patients who received laparoscopic myomectomy in our hospital from May 2012 to October 2014 into dexmedetomidine group (Dex group) and control group (Con group), and postoperative mechanical pain threshold and emergence agitation extent were assessed.Results: 4 h, 8 h, 12 h and 24 h after operation, mechanical pain threshold of both Dex group and Con group were significantly lower than those before operation (P<0.05) and mechanical pain threshold of Dex group 4 h, 8 h, 12 h and 24 h after operation were significantly higher than those of Con group (P<0.05); both incidence and average grade of emergence agitation of Dex group were significantly lower than those of Con group (P<0.05); serum melatonin content of Dex group in recovery period were not significantly different from those in anesthesia induction period, serum melatonin content of Con group in recovery period were significantly lower than those in anesthesia induction period, and serum melatonin content of Dex group in recovery period were significantly higher than those of Con group (P<0.05); serum cortisol content of both Dex group and Con group in recovery period were significantly higher than those before anesthesia induction and cortisol content of Dex group in recovery period was significantly lower than that of Con group (P<0.05).Conclusions:Dexmedetomidine for laparoscopic myomectomy can reduce postoperative hyperalgesia and prevent emergence agitation, and it has positive clinical value.

  9. Drug-Induced Apoptosis: Mechanism by which Alcohol and Many Other Drugs Can Disrupt Brain Development

    Directory of Open Access Journals (Sweden)

    John W. Olney

    2013-07-01

    Full Text Available Maternal ingestion of alcohol during pregnancy can cause a disability syndrome termed Fetal Alcohol Spectrum Disorder (FASD, which may include craniofacial malformations, structural pathology in the brain, and a variety of long-term neuropsychiatric disturbances. There is compelling evidence that exposure to alcohol during early embryogenesis (4th week of gestation can cause excessive death of cell populations that are essential for normal development of the face and brain. While this can explain craniofacial malformations and certain structural brain anomalies that sometimes accompany FASD, in many cases these features are absent, and the FASD syndrome manifests primarily as neurobehavioral disorders. It is not clear from the literature how alcohol causes these latter manifestations. In this review we will describe a growing body of evidence documenting that alcohol triggers widespread apoptotic death of neurons and oligodendroglia (OLs in the developing brain when administered to animals, including non-human primates, during a period equivalent to the human third trimester of gestation. This cell death reaction is associated with brain changes, including overall or regional reductions in brain mass, and long-term neurobehavioral disturbances. We will also review evidence that many drugs used in pediatric and obstetric medicine, including general anesthetics (GAs and anti-epileptics (AEDs, mimic alcohol in triggering widespread apoptotic death of neurons and OLs in the third trimester-equivalent animal brain, and that human children exposed to GAs during early infancy, or to AEDs during the third trimester of gestation, have a significantly increased incidence of FASD-like neurobehavioral disturbances. These findings provide evidence that exposure of the developing human brain to GAs in early infancy, or to alcohol or AEDs in late gestation, can cause FASD-like neurodevelopmental disability syndromes. We propose that the mechanism by which

  10. Emerging complexity in a simple model of the mechanical behaviour of rocks

    CERN Document Server

    Amitrano, David

    2004-01-01

    We propose a mechanical model for the behaviour of rocks based on progressive damage at the elementary scale and elastic interaction. It allows us to simulate several experimental observations: mechanical behaviour ranging from brittle to ductile, fractal structure of the damage, powerlaw distribution of the damage avalanches. These macroscopic properties are not incorporated at the elementary scale, but are the results of the interaction between elements. This emerging complexity permits us to consider the strain rock process as a complex system characterized by non-linear dynamics.

  11. The radical-pair mechanism as a paradigm for the emerging science of quantum biology

    CERN Document Server

    Kominis, I K

    2015-01-01

    The radical-pair mechanism was introduced in the 1960's to explain anomalously large EPR and NMR signals in chemical reactions of organic molecules. It has evolved to the cornerstone of spin chemistry, the study of the effect electron and nuclear spins have on chemical reactions, with the avian magnetic compass mechanism and the photosynthetic reaction center dynamics being prominent biophysical manifestations of such effects. In recent years the radical-pair mechanism was shown to be an ideal biological system where the conceptual tools of quantum information science can be fruitfully applied. We will here review recent work making the case that the radical-pair mechanism is indeed a major driving force of the emerging field of quantum biology.

  12. Mechanisms underlying brain monitoring during anesthesia: limitations, possible improvements, and perspectives.

    Science.gov (United States)

    Cascella, Marco

    2016-04-01

    Currently, anesthesiologists use clinical parameters to directly measure the depth of anesthesia (DoA). This clinical standard of monitoring is often combined with brain monitoring for better assessment of the hypnotic component of anesthesia. Brain monitoring devices provide indices allowing for an immediate assessment of the impact of anesthetics on consciousness. However, questions remain regarding the mechanisms underpinning these indices of hypnosis. By briefly describing current knowledge of the brain's electrical activity during general anesthesia, as well as the operating principles of DoA monitors, the aim of this work is to simplify our understanding of the mathematical processes that allow for translation of complex patterns of brain electrical activity into dimensionless indices. This is a challenging task because mathematical concepts appear remote from clinical practice. Moreover, most DoA algorithms are proprietary algorithms and the difficulty of exploring the inner workings of mathematical models represents an obstacle to accurate simplification. The limitations of current DoA monitors - and the possibility for improvement - as well as perspectives on brain monitoring derived from recent research on corticocortical connectivity and communication are also discussed. PMID:27066200

  13. Some historical notes on the diagnosis of death--the emergence of the brain death concept.

    Science.gov (United States)

    Kinnaert, P

    2009-01-01

    This paper demonstrates that discussions about the diagnosis of death and the meaning of states of suspended animation existed long before the publication of the Harvard criteria in 1968. The surgeons who started retrieving kidneys from heart beating cadavers have been accused to redefine death in order to obtain high quality organs. In fact, they were not aware of modifying a definition. They did not view death as a philosophical concept but considered that it was a biological phenomenon of which brain death was merely a new expression resulting from the development of resuscitation and intensive care procedures. PMID:19943608

  14. The Third Annual Deep Brain Stimulation Think Tank: A Review of Emerging Issues and Technologies

    Directory of Open Access Journals (Sweden)

    P. Justin eRossi

    2016-04-01

    Full Text Available This review summarizes the most contemporary clinical, electrophysiological, imaging, and computational work on DBS for the treatment of neurological and neuropsychiatric disease. Significant innovations of the past year are emphasized; these advances were presented at the 3rd Annual Deep Brain Stimulation Think Tank. The Think Tank’s contributors represent a unique multidisciplinary ensemble of expert neurologists, neurosurgeons, neuropsychologists, psychiatrists, scientists, engineers, and members of industry. Presentations and discussions covered a broad range of topics, including policy and advocacy considerations for the future of DBS, connectomic approaches to DBS targeting, developments in electrophysiology and related strides toward responsive DBS systems, and recent developments in sensor and device technologies.

  15. Management of critically ill patients receiving noninvasive and invasive mechanical ventilation in the emergency department

    Directory of Open Access Journals (Sweden)

    Rose L

    2012-03-01

    Full Text Available Louise RoseLawrence S Bloomberg Faculty of Nursing, University of Toronto, Toronto, Ontario, CanadaAbstract: Patients requiring noninvasive and invasive ventilation frequently present to emergency departments, and may remain for prolonged periods due to constrained critical care services. Emergency clinicians often do not receive the same education on management of mechanical ventilation or have similar exposure to these patients as do their critical care colleagues. The aim of this review was to synthesize the evidence on management of patients requiring noninvasive and invasive ventilation in the emergency department including indications, clinical applications, monitoring priorities, and potential complications. Noninvasive ventilation is recommended for patients with acute exacerbation of chronic obstructive pulmonary disease or cardiogenic pulmonary edema. Less evidence supports its use in asthma and other causes of acute respiratory failure. Use of noninvasive ventilation in the prehospital setting is relatively new, and some evidence suggests benefit. Monitoring priorities for noninvasive ventilation include response to treatment, respiratory and hemodynamic stability, noninvasive ventilation tolerance, detection of noninvasive ventilation failure, and identification of air leaks around the interface. Application of injurious ventilation increases patient morbidity and mortality. Lung-protective ventilation with low tidal volumes based on determination of predicted body weight and control of plateau pressure has been shown to reduce mortality in patients with acute respiratory distress syndrome, and some evidence exists to suggest this strategy should be used in patients without lung injury. Monitoring of the invasively ventilated patient should focus on assessing response to mechanical ventilation and other interventions, and avoiding complications, such as ventilator-associated pneumonia. Several key aspects of management of noninvasive

  16. Shaping the aging brain: Role of auditory input patterns in the emergence of auditory cortical impairments

    Directory of Open Access Journals (Sweden)

    Brishna Soraya Kamal

    2013-09-01

    Full Text Available Age-related impairments in the primary auditory cortex (A1 include poor tuning selectivity, neural desynchronization and degraded responses to low-probability sounds. These changes have been largely attributed to reduced inhibition in the aged brain, and are thought to contribute to substantial hearing impairment in both humans and animals. Since many of these changes can be partially reversed with auditory training, it has been speculated that they might not be purely degenerative, but might rather represent negative plastic adjustments to noisy or distorted auditory signals reaching the brain. To test this hypothesis, we examined the impact of exposing young adult rats to 8 weeks of low-grade broadband noise on several aspects of A1 function and structure. We then characterized the same A1 elements in aging rats for comparison. We found that the impact of noise exposure on A1 tuning selectivity, temporal processing of auditory signal and responses to oddball tones was almost indistinguishable from the effect of natural aging. Moreover, noise exposure resulted in a reduction in the population of parvalbumin inhibitory interneurons and cortical myelin as previously documented in the aged group. Most of these changes reversed after returning the rats to a quiet environment. These results support the hypothesis that age-related changes in A1 have a strong activity-dependent component and indicate that the presence or absence of clear auditory input patterns might be a key factor in sustaining adult A1 function.

  17. Pulsations with reflected boundary waves: a hydrodynamic reverse transport mechanism for perivascular drainage in the brain.

    Science.gov (United States)

    Coloma, M; Schaffer, J D; Carare, R O; Chiarot, P R; Huang, P

    2016-08-01

    Beta-amyloid accumulation within arterial walls in cerebral amyloid angiopathy is associated with the onset of Alzheimer's disease. However, the mechanism of beta-amyloid clearance along peri-arterial pathways in the brain is not well understood. In this study, we investigate a transport mechanism in the arterial basement membrane consisting of forward-propagating waves and their reflections. The arterial basement membrane is modeled as a periodically deforming annulus filled with an incompressible single-phase Newtonian fluid. A reverse flow, which has been suggested in literature as a beta-amyloid clearance pathway, can be induced by the motion of reflected boundary waves along the annular walls. The wave amplitude and the volume of the annular region govern the flow magnitude and may have important implications for an aging brain. Magnitudes of transport obtained from control volume analysis and numerical solutions of the Navier-Stokes equations are presented. PMID:26729476

  18. Emergency Department Visits for Traumatic Brain Injury in Older Adults in the United States: 2006-08

    Directory of Open Access Journals (Sweden)

    William S. Pearson

    2012-08-01

    Full Text Available Introduction: Traumatic brain injury (TBI can be complicated among older adults due to age-related frailty, a greater prevalence of chronic conditions and the use of anticoagulants. We conducted this study using the latest available, nationally-representative emergency department (ED data to characterize visits for TBI among older adults.Methods: We used the 2006-2008 National Hospital Ambulatory Medical Care – Emergency Department (NHAMCS-ED data to examine ED visits for TBI among older adults. Population-level estimates of triage immediacy, receipt of a head computed tomography (CT and/or head magnetic resonance imaging (MRI, and hospital admission by type were used to characterize 1,561 sample visits, stratified by age <65 and ≥65 years of age.Results: Of ED visits made by persons ≥65 years of age, 29.1% required attention from a physician within 15 minutes of arrival; 82.1% required a head CT, and 20.9% required hospitalization. Persons≥65 years of age were 3 times more likely to receive a head CT or MRI compared to younger patients presenting with TBI (adjusted odds ratio [aOR] 3.2; 95% confidence interval [CI], 1.8-5.8, and were 4 times more likely to be admitted to an intensive care unit, step-down unit, or surgery (aOR 4.1; 95% CI 2.1-8.0 compared to younger patients presenting with TBI, while controlling for sex and race.Conclusion: Results demonstrate increased emergent service delivery for older persons presenting with TBI. As the United States population ages and continues to grow, TBI will become an even more important public health issue that will place a greater demand on the healthcare system. [West J Emerg Med. 2012;13(3:289-293.

  19. PREFACE: DICE 2008 - From Quantum Mechanics through Complexity to Spacetime: the role of emergent dynamical structures

    Science.gov (United States)

    Diósi, Lajos; Elze, Hans-Thomas; Fronzoni, Leone; Halliwell, Jonathan; Vitiello, Giuseppe

    2009-07-01

    Pasquini, which - with its beautiful surroundings, overlooking a piece of Tuscany's coast, and with splendid weather throughout - was conducive to the success of the meeting. The 5-day program was grouped according to the following topics: Quantum Physics and Some Important Questions it Raises Emergent Dynamics, from Quantum to Brain and Beyond Exploring Quantum Mechanics Atomistic Theories of Spacetime Quantum-Entanglement/Gravity/Cosmology A Public Roundtable Discussion formed an integral part of the program under the theme ``Dialoghi sulla complessita' - dall' atomo all' Universo'' and with the participation of physicists and philosophers: F T Arecchi (Firenze), L Fronzoni (Pisa), A M Iacono (Pisa), F Luccio (Pisa) and G Vitiello (Salerno, coordinator). This event drew a large audience, who participated in the lively discussions until late in the evening. The workshop has been organized by L Diósi (Budapest), H-T Elze (Pisa, chair), L Fronzoni (Pisa), J Halliwell (London) and G Vitiello (Salerno), with great help from our conference secretaries M Pesce-Rollins (Siena) and L Baldini (Pisa) and from our students F Caravelli and E Di Nardo, both from Pisa. Several institutions and sponsors generously supported the workshop and their representatives and, in particular, the citizens of Rosignano/Castiglioncello are deeply thanked for the help and kind hospitality: Comune di Rosignano A Nenci (Sindaco di Rosignano), S Scarpellini (Segreteria sindaco), D Del Seppia (Assessore allo Sviluppo Economico del Comune di Rosignano), A Franchi (Assessore al turismo del Comune di Rosignano/Presidente dell' associazione Armunia), A Corsini (Ufficio economato del Comune di Rosignano). REA Rosignano Energia Ambiente s.p.a. F Ghelardini (Presidente della REA), A Cecchini (Ufficio - Responsabile stampa della REA). Solvay Chimica Italia s.a. Dott S Piccoli (Responsabile Relazioni Esterne, Solvay Rosignano), G Becherucci (Comunicazione e Relazioni Esterne). Associazione Armunia M Paganelli

  20. Selective Sensation Based Brain-Computer Interface via Mechanical Vibrotactile Stimulation

    OpenAIRE

    Lin Yao; Jianjun Meng; Dingguo Zhang; Xinjun Sheng; Xiangyang Zhu

    2013-01-01

    In this work, mechanical vibrotactile stimulation was applied to subjects' left and right wrist skins with equal intensity, and a selective sensation perception task was performed to achieve two types of selections similar to motor imagery Brain-Computer Interface. The proposed system was based on event-related desynchronization/synchronization (ERD/ERS), which had a correlation with processing of afferent inflow in human somatosensory system, and attentional effect which modulated the ERD/ER...

  1. THE EFFECTS OF AN INCENTIVE MECHANISM ON BRAIN DRAIN IN THE HOTEL INDUSTRY

    OpenAIRE

    Zhao, Danni

    2016-01-01

    This thesis studies the effects of incentive mechanism on brain drain in hotel industry. As for the reason why this topic is chosen, it is regarding to the author's previous working experiences in the hotel industry. After the training practice in several different hotels, it is notable that Chinese hotel industry is confronted with a severe problem of high employee turnover. While the normal human resource turnover rate should remain between 5% and 10%, the average figure for the hotel staff...

  2. How long-term mindfulness meditation practice affects the brain mechanisms of attention?

    OpenAIRE

    Roininen, Minna

    2015-01-01

    In the last few decades, the beneficial effects of meditation and mindfulness have been broadly researched. Because attention plays a key role in mindfulness, it has been assumed that long-term practice of mindfulness meditation also has an impact on attention on neurophysiological level.In the current study, we explored how the long-term practice of mindfulness meditation affects the brain mechanisms of attention. We compared two groups, long-term meditation practisers and medita...

  3. Mechanical and Biological Interactions of Implants with the Brain and Their Impact on Implant Design.

    Science.gov (United States)

    Prodanov, Dimiter; Delbeke, Jean

    2016-01-01

    Neural prostheses have already a long history and yet the cochlear implant remains the only success story about a longterm sensory function restoration. On the other hand, neural implants for deep brain stimulation are gaining acceptance for variety of disorders including Parkinsons disease and obsessive-compulsive disorder. It is anticipated that the progress in the field has been hampered by a combination of technological and biological factors, such as the limited understanding of the longterm behavior of implants, unreliability of devices, biocompatibility of the implants among others. While the field's understanding of the cell biology of interactions at the biotic-abiotic interface has improved, relatively little attention has been paid on the mechanical factors (stress, strain), and hence on the geometry that can modulate it. This focused review summarizes the recent progress in the understanding of the mechanisms of mechanical interaction between the implants and the brain. The review gives an overview of the factors by which the implants interact acutely and chronically with the tissue: blood-brain barrier (BBB) breach, vascular damage, micromotions, diffusion etc. We propose some design constraints to be considered in future studies. Aspects of the chronic cell-implant interaction will be discussed in view of the chronic local inflammation and the ways of modulating it. PMID:26903786

  4. Ultra-fast magnetic resonance encephalography of physiological brain activity - Glymphatic pulsation mechanisms?

    Science.gov (United States)

    Kiviniemi, Vesa; Wang, Xindi; Korhonen, Vesa; Keinänen, Tuija; Tuovinen, Timo; Autio, Joonas; LeVan, Pierre; Keilholz, Shella; Zang, Yu-Feng; Hennig, Jürgen; Nedergaard, Maiken

    2016-06-01

    The theory on the glymphatic convection mechanism of cerebrospinal fluid holds that cardiac pulsations in part pump cerebrospinal fluid from the peri-arterial spaces through the extracellular tissue into the peri-venous spaces facilitated by aquaporin water channels. Since cardiac pulses cannot be the sole mechanism of glymphatic propulsion, we searched for additional cerebrospinal fluid pulsations in the human brain with ultra-fast magnetic resonance encephalography. We detected three types of physiological mechanisms affecting cerebral cerebrospinal fluid pulsations: cardiac, respiratory, and very low frequency pulsations. The cardiac pulsations induce a negative magnetic resonance encephalography signal change in peri-arterial regions that extends centrifugally and covers the brain in ≈1 Hz cycles. The respiratory ≈0.3 Hz pulsations are centripetal periodical pulses that occur dominantly in peri-venous areas. The third type of pulsation was very low frequency (VLF 0.001-0.023 Hz) and low frequency (LF 0.023-0.73 Hz) waves that both propagate with unique spatiotemporal patterns. Our findings using critically sampled magnetic resonance encephalography open a new view into cerebral fluid dynamics. Since glymphatic system failure may precede protein accumulations in diseases such as Alzheimer's dementia, this methodological advance offers a novel approach to image brain fluid dynamics that potentially can enable early detection and intervention in neurodegenerative diseases. PMID:26690495

  5. Role of MicroRNAs in innate neuroprotection mechanisms due to preconditioning of the brain

    Directory of Open Access Journals (Sweden)

    Eva Maria Jimenez-Mateos

    2015-04-01

    Full Text Available Insults to the brain that are sub-threshold for damage activate endogenous protective pathways, which can temporarily protect the brain against a subsequent harmful episode. This mechanism has been named as tolerance and its protective effects have been shown in experimental models of ischemia and epilepsy. The preconditioning-stimulus can be a short period of ischemia or mild seizures induced by low doses of convulsant drugs.Gene-array profiling has shown that both ischemic and epileptic tolerance feature large-scale gene down-regulation but the mechanism are unknown. MicroRNAs are a class of small non-coding RNAs of ~20-22 nucleotides length which regulate gene expression at a post-transcriptional level via mRNA degradation or inhibition of protein translation. MicroRNAs have been shown to be regulated after non-harmful and harmful stimuli in the brain and to contribute to neuroprotective mechanisms. This review focuses on the role of microRNAs in the development of tolerance following ischemic or epileptic preconditioning.

  6. Emergency CT brain: preliminary interpretation with a tablet device: image quality and diagnostic performance of the Apple iPad.

    LENUS (Irish Health Repository)

    Mc Laughlin, Patrick

    2012-04-01

    Tablet devices have recently been used in radiological image interpretation because they have a display resolution comparable to desktop LCD monitors. We identified a need to examine tablet display performance prior to their use in preliminary interpretation of radiological images. We compared the spatial and contrast resolution of a commercially available tablet display with a diagnostic grade 2 megapixel monochrome LCD using a contrast detail phantom. We also recorded reporting discrepancies, using the ACR RADPEER system, between preliminary interpretation of 100 emergency CT brain examinations on the tablet display and formal review on a diagnostic LCD. The iPad display performed inferiorly to the diagnostic monochrome display without the ability to zoom. When the software zoom function was enabled on the tablet device, comparable contrast detail phantom scores of 163 vs 165 points were achieved. No reporting discrepancies were encountered during the interpretation of 43 normal examinations and five cases of acute intracranial hemorrhage. There were seven RADPEER2 (understandable) misses when using the iPad display and 12 with the diagnostic LCD. Use of software zoom in the tablet device improved its contrast detail phantom score. The tablet allowed satisfactory identification of acute CT brain findings, but additional research will be required to examine the cause of "understandable" reporting discrepancies that occur when using tablet devices.

  7. Integrating early life experience, gene expression, brain development, and emergent phenotypes: unraveling the thread of nature via nurture.

    Science.gov (United States)

    Weaver, Ian C G

    2014-01-01

    Adaptation to environmental changes is based on the perpetual generation of new phenotypes. Modern biology has focused on the role of epigenetic mechanisms in facilitating the adaptation of organisms to changing environments through alterations in gene expression. Inherited and/or acquired epigenetic factors are relatively stable and have regulatory roles in numerous genomic activities that translate into phenotypic outcomes. Evidence that dietary and pharmacological interventions have the potential to reverse environment-induced modification of epigenetic states (e.g., early life experience, nutrition, medication, infection) has provided an additional stimulus for understanding the biological basis of individual differences in cognitive abilities and disorders of the brain. It has been suggested that accurate quantification of the relative contribution of heritable genetic and epigenetic variation is essential for understanding phenotypic divergence and adaptation in changing environments, a process requiring stable modulation of gene expression. The main challenge for epigenetics in psychology and psychiatry is to determine how experiences and environmental cues, including the nature of our nurture, influence the expression of neuronal genes to produce long-term individual differences in behavior, cognition, personality, and mental health. To this end, focusing on DNA and histone modifications and their initiators, mediators and readers may provide new inroads for understanding the molecular basis of phenotypic plasticity and disorders of the brain. In this chapter, we review recent discoveries highlighting epigenetic aspects of normal brain development and mental illness, as well as discuss some future directions in the field of behavioral epigenetics.

  8. Making better scar: Emerging approaches for modifying mechanical and electrical properties following infarction and ablation.

    Science.gov (United States)

    Holmes, Jeffrey W; Laksman, Zachary; Gepstein, Lior

    2016-01-01

    Following myocardial infarction (MI), damaged myocytes are replaced by collagenous scar tissue, which serves an important mechanical function - maintaining integrity of the heart wall against enormous mechanical forces - but also disrupts electrical function as structural and electrical remodeling in the infarct and borderzone predispose to re-entry and ventricular tachycardia. Novel emerging regenerative approaches aim to replace this scar tissue with viable myocytes. Yet an alternative strategy of therapeutically modifying selected scar properties may also prove important, and in some cases may offer similar benefits with lower risk or regulatory complexity. Here, we review potential goals for such modifications as well as recent proof-of-concept studies employing specific modifications, including gene therapy to locally increase conduction velocity or prolong the refractory period in and around the infarct scar, and modification of scar anisotropy to improve regional mechanics and pump function. Another advantage of scar modification techniques is that they have applications well beyond MI. In particular, ablation treats electrical abnormalities of the heart by intentionally generating scar to block aberrant conduction pathways. Yet in diseases such as atrial fibrillation (AF) where ablation can be extensive, treating the electrical disorder can significantly impair mechanical function. Creating smaller, denser scars that more effectively block conduction, and choosing the location of those lesions by balancing their electrical and mechanical impacts, could significantly improve outcomes for AF patients. We review some recent advances in this area, including the use of computational models to predict the mechanical effects of specific lesion sets and gene therapy for functional ablation. Overall, emerging techniques for modifying scar properties represents a potentially important set of tools for improving patient outcomes across a range of heart diseases

  9. Meta-Analyses of Developing Brain Function in High-Risk and Emerged Bipolar Disorder

    Directory of Open Access Journals (Sweden)

    Moon-Soo eLee

    2014-11-01

    Full Text Available Objectives: Identifying early markers of brain function among those at high risk for pediatric bipolar disorder (PBD could serve as a screening measure when children and adolescents present with sub-syndromal clinical symptoms prior to the conversion to bipolar disorder. Studies on the offspring of patients with bipolar disorder who are genetically at high risk (HR have each been limited in establishing a biomarker, while an analytic review in summarizing the findings offers an improvised opportunity towards that goal. Methods: An activation likelihood estimation meta-analysis of mixed cognitive and emotional activities using the GingerALE software from the BrainMap Project was completed. The meta-analysis of all fMRI studies contained a total of 29 reports and included PBD, HR and typically developing (TD groups.Results: The HR group showed significantly greater activation relative to the TD group in the right DLPFC-insular-parietal-cerebellar regions. Similarly, the HR group exhibited greater activity in the right DLPFC and insula as well as the left cerebellum compared to patients with PBD. Patients with PBD, relative to TD, showed greater activation in regions of the right amygdala, parahippocampal gyrus, medial PFC, left ventral striatum, and cerebellum and lower activation in the right VLPFC and the DLPFC.Conclusions: The HR population showed increased activity, presumably indicating greater compensatory deployment, in relation to both the TD and the PBD, in the key cognition and emotion processing regions, such as the DLPFC, insula and parietal cortex. In contrast, patients with PBD, relative to HR and TD, showed decreased activity, which could indicate a decreased effort in multiple PFC regions in addition to widespread subcortical abnormalities, which are suggestive of a more entrenched disease process.

  10. The emergence of grammar in a language-ready brain. Comment on "Towards a Computational Comparative Neuroprimatology: Framing the language-ready brain" by Michael A. Arbib

    Science.gov (United States)

    Hawkins, John A.

    2016-03-01

    Arbib makes the interesting proposal [3, §1.6] that the first Homo sapiens could have been "language-ready", without possessing the kind of rich lexicon, grammar and compositional semantics that we see in the world's languages today. This early language readiness would have consisted of a set of "protolanguage" abilities, which he enumerates (1-7 in §1.6), supported by brain mechanisms unique to humans. The transition to full "language" (properties 8-11 in §1.6 and §3) would have required no changes in the genome, he argues, but could have resulted from cultural evolution plus some measure of Baldwinian evolution favoring offspring with greater linguistic skill. The full picture is set out in [1].

  11. 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

  12. Mechanical Characterization of Brain Tissue in Compression at Dynamic Strain Rates

    CERN Document Server

    Rashid, Badar; Gilchrist, Michael; 10.1016/j.jmbbm.2012.01.022

    2013-01-01

    Traumatic brain injury (TBI) occurs when local mechanical load exceeds certain tolerance levels for brain tissue. Extensive research has been done previously for brain matter experiencing compression at quasistatic loading; however, limited data is available to model TBI under dynamic impact conditions. In this research, an experimental setup was developed to perform unconfined compression tests and stress relaxation tests at strain rates < 90/s. The brain tissue showed a stiffer response with increasing strain rates, showing that hyperelastic models are not adequate. Specifically, the compressive nominal stress at 30% strain was 8.83 +/- 1.94, 12.8 +/- 3.10 and 16.0 +/- 1.41 kPa (mean +/- SD) at strain rates of 30, 60 and 90/s, respectively. Relaxation tests were also conducted at 10%-50% strain with the average rise time of 10 ms, which can be used to derive time dependent parameters. Numerical simulations were performed using one-term Ogden model with initial shear modulus mu_0 = 6.06 +/- 1.44, 9.44 +/-...

  13. A meta-analysis of brain mechanisms of placebo analgesia: consistent findings and unanswered questions.

    Science.gov (United States)

    Atlas, Lauren Y; Wager, Tor D

    2014-01-01

    Placebo treatments reliably reduce pain in the clinic and in the lab. Because pain is a subjective experience, it has been difficult to determine whether placebo analgesia is clinically relevant. Neuroimaging studies of placebo analgesia provide objective evidence of placebo-induced changes in brain processing and allow researchers to isolate the mechanisms underlying placebo-based pain reduction. We conducted formal meta-analyses of 25 neuroimaging studies of placebo analgesia and expectancy-based pain modulation. Results revealed that placebo effects and expectations for reduced pain elicit reliable reductions in activation during noxious stimulation in regions often associated with pain processing, including the dorsal anterior cingulate, thalamus, and insula. In addition, we observed consistent reductions during painful stimulation in the amygdala and striatum, regions implicated widely in studies of affect and valuation. This suggests that placebo effects are strongest on brain regions traditionally associated with not only pain, but also emotion and value more generally. Other brain regions showed reliable increases in activation with expectations for reduced pain. These included the prefrontal cortex (including dorsolateral, ventromedial, and orbitofrontal cortices), the midbrain surrounding the periaqueductal gray, and the rostral anterior cingulate. We discuss implications of these findings as well as how future studies can expand our understanding of the precise functional contributions of the brain systems identified here.

  14. Imaging social motivation: distinct brain mechanisms drive effort production during collaboration versus competition.

    Science.gov (United States)

    Le Bouc, Raphaël; Pessiglione, Mathias

    2013-10-01

    Collaborative and competitive interactions have been investigated extensively so as to understand how the brain makes choices in the context of strategic games, yet such interactions are known to influence a more basic dimension of behavior: the energy invested in the task. The cognitive mechanisms that motivate effort production in social situations remain poorly understood, and their neural counterparts have not been explored so far. A dominant idea is that the motivation provided by the social context is reducible to the personal utility of effort production, which decreases in collaboration and increases in competition. Using functional magnetic resonance imaging, we scanned human participants while they produced a physical effort in a collaborative or competitive context. We found that motivation was indeed primarily driven by personal utility, which was reflected in brain regions devoted to reward processing (the ventral basal ganglia). However, subjects who departed from utility maximization, working more in collaborative situations, showed greater functional activation and anatomical volume in a brain region implicated previously in social cognition (the temporoparietal junction). Therefore, this region might mediate a purely pro-social motivation to produce greater effort in the context of collaboration. More generally, our findings suggest that the individual propensity to invest energy in collaborative work might have an identifiable counterpart in the brain functional architecture.

  15. [Mechanism of "treating heart and brain with same methods" based on data science].

    Science.gov (United States)

    Chen, Di; Tang, Shi-huan; Lu, Peng; Yang, Hong-jun

    2015-11-01

    The traditional Chinese medicine (TCM) theory of "treating heart and brain diseases with same methods (Nao Xin Tong Zhi: NXTZ)" has great significance to the treatment of cardiovascular and cerebrovascular diseases. It has been proven effective by a great deal of clinical researches. However, the underlying mechanism for this theory is still unclear. To provide insights into the potential mechanism of "NXTZ", this study attempts to deeply investigate the mechanism from two representative cardiovascular and cerebrovascular diseases, coronary heart disease (CHD) and cerebral apoplexy. First, various data resources were integrated to obtain different types of biomedical entities including drugs, targets, pathways and diseases. Then, three different approaches including text mining, biological network and enrichment analysis were utilized to recognize the potential common features between CHD and cerebral apoplexy, and the corresponding functions of drugs which could treat both diseases, thus unveiling the mechanism of NXTZ. PMID:27071272

  16. Emergent Structural Mechanisms for High-Density Collective Motion Inspired by Human Crowds

    CERN Document Server

    Bottinelli, Arianna; Silverberg, Jesse L

    2016-01-01

    Collective motion of large human crowds often depends on their density. In extreme cases like heavy metal concerts and Black Friday sales events, motion is dominated by physical interactions instead of conventional social norms. Here, we study an active matter model inspired by situations when large groups of people gather at a point of common interest. Our analysis takes an approach developed for jammed granular media and identifies Goldstone modes, soft spots, and stochastic resonance as structurally-driven mechanisms for potentially dangerous emergent collective motion.

  17. The 3rd International Conference on Continental Earthquakes, Mechanism, Prediction, Emergency Management & Insurance

    Institute of Scientific and Technical Information of China (English)

    Dr.HuangJing

    2004-01-01

    The 3rd International Conference on Continental Earthquakes, Mechanism, Prediction, Emergency Management & Insurance (the 3rd ICCE) was held on July 9-14, 2004 in Beijing, China. The ICCE has been held every decade since it was launched over twenty years ago. The first ICCE, with the title """"International Symposium on Continental Seismicity and Earthquake Prediction""""(ISCSEP), had international sponsorship and was supported by e.g., UNESCO and hosted by the Seismological Society of China (SSC)in Beijing in 1982. In 1992 in response to the initiatives from the UN's International Decade for Natural Disaster Reduction (IDNDR),

  18. Shaping and reshaping the aesthetic brain: Emerging perspectives on the neurobiology of embodied aesthetics.

    Science.gov (United States)

    Kirsch, Louise P; Urgesi, Cosimo; Cross, Emily S

    2016-03-01

    Less than two decades after its inception, the burgeoning field of neuroaesthetics continues to grow in interest and momentum. Despite the biological and social importance of the human body and the attention people pay to its appearance in daily life, only recently has neuroaesthetic inquiry turned its attention to questions concerning the aesthetic appraisal of the human body. We review evidence illustrating that the complexity of aesthetic experience is reflected by dynamic interplay between brain systems involved in reward, perceptual and motor processing, with a focus on aesthetic perception involving the human body. We then evaluate work demonstrating how these systems are modulated by beholders' expertise or familiarity. Finally, we discuss seminal studies revealing the plasticity of behavioural and neural responses to beauty after perceptual and motor training. This research highlights the rich potential for neuroaesthetic inquiry to extend beyond its typical realm of the fine arts to address important questions regarding the relationship between embodiment, aesthetics and performing arts. We conclude by considering some of the criticisms and limitations of neuroaesthetics, and highlight several outstanding issues for future inquiry. PMID:26698020

  19. The Acute Inflammatory Response in Trauma / Hemorrhage and Traumatic Brain Injury: Current State and Emerging Prospects

    Directory of Open Access Journals (Sweden)

    Y Vodovotz

    2009-01-01

    Full Text Available Traumatic injury/hemorrhagic shock (T/HS elicits an acute inflammatory response that may result in death. Inflammation describes a coordinated series of molecular, cellular, tissue, organ, and systemic responses that drive the pathology of various diseases including T/HS and traumatic brain injury (TBI. Inflammation is a finely tuned, dynamic, highly-regulated process that is not inherentlydetrimental, but rather required for immune surveillance, optimal post-injury tissue repair, and regeneration. The inflammatory response is driven by cytokines and chemokines and is partiallypropagated by damaged tissue-derived products (Damage-associated Molecular Patterns; DAMP’s.DAMPs perpetuate inflammation through the release of pro-inflammatory cytokines, but may also inhibit anti-inflammatory cytokines. Various animal models of T/HS in mice, rats, pigs, dogs, and nonhumanprimates have been utilized in an attempt to move from bench to bedside. Novel approaches, including those from the field of systems biology, may yield therapeutic breakthroughs in T/HS andTBI in the near future.

  20. Shaping and reshaping the aesthetic brain: Emerging perspectives on the neurobiology of embodied aesthetics.

    Science.gov (United States)

    Kirsch, Louise P; Urgesi, Cosimo; Cross, Emily S

    2016-03-01

    Less than two decades after its inception, the burgeoning field of neuroaesthetics continues to grow in interest and momentum. Despite the biological and social importance of the human body and the attention people pay to its appearance in daily life, only recently has neuroaesthetic inquiry turned its attention to questions concerning the aesthetic appraisal of the human body. We review evidence illustrating that the complexity of aesthetic experience is reflected by dynamic interplay between brain systems involved in reward, perceptual and motor processing, with a focus on aesthetic perception involving the human body. We then evaluate work demonstrating how these systems are modulated by beholders' expertise or familiarity. Finally, we discuss seminal studies revealing the plasticity of behavioural and neural responses to beauty after perceptual and motor training. This research highlights the rich potential for neuroaesthetic inquiry to extend beyond its typical realm of the fine arts to address important questions regarding the relationship between embodiment, aesthetics and performing arts. We conclude by considering some of the criticisms and limitations of neuroaesthetics, and highlight several outstanding issues for future inquiry.

  1. PREFACE: EmerQuM 11: Emergent Quantum Mechanics 2011 (Heinz von Foerster Congress)

    Science.gov (United States)

    Grössing, Gerhard

    2012-05-01

    These proceedings comprise the plenary lectures and poster contributions of the 'Heinz von Foerster Conference 2011' on Emergent Quantum Mechanics (EmerQuM11), which was held at the University of Vienna, 11-13 November 2011. With the 5th International Heinz von Foerster Conference convened at the occasion of von Foerster's 100th birthday, the organizers opted for a twin conference to take place at the Large and Small Ceremonial Halls of the University's main building, respectively. The overall topic was chosen as 'Self-Organization and Emergence', a topic to which von Foerster was an early contributor. While the first conference ('Self-Organization and Emergence in Nature and Society') addressed a more general audience, the second one ('Emergent Quantum Mechanics') was intended as a specialist meeting with a contemporary topic that could both serve as an illustration of von Foerster's intellectual heritage and, more generally, point towards future directions in physics. We thus intended to bring together many of those physicists who are interested in or are working on attempts to understand quantum mechanics as emerging from a suitable classical (or, more generally, deeper level) physics. EmerQuM11 was organized by the Austrian Institute for Nonlinear Studies (AINS), with essential support from the Wiener Institute for Social Science Documentation and Methodology (WISDOM), the Department of Contemporary History at the University of Vienna, and the Heinz von Foerster-Gesellschaft. There were a number of individuals who contributed to the smooth course of our meeting and whom I would like to sincerely thank: Christian Bischof, Thomas Elze, Marianne Ertl, Gertrud Hafner, Werner Korn, Angelika Krawanja, Florian Krug and his team, Sonja Lang, Albert Müller, Ilse Müller, Irene Müller, Karl Müller, Armin Reautschnig, Marion Schirrmacher, Anton Staudinger, Roman Zlabinger, and, last but not least, my AINS colleagues Siegfried Fussy, Herbert Schwabl and Johannes Mesa

  2. Origin and evolution of antibiotic resistance: the common mechanisms of emergence and spread in water bodies

    Directory of Open Access Journals (Sweden)

    Agnese eLupo

    2012-01-01

    Full Text Available The environment, and especially fresh water, constitutes a reactor where the evolution and the rise of new resistances occur. In rivers or streams, bacteria from different sources such as urban, industrial and agricultural waste, probably selected by intensive antibiotic usage, are collected and mixed with environmental species. This may cause two effects on the development of antibiotic resistances: First, the contamination of water by antibiotics or other pollutants lead to the rise of resistance due to selection processes. For instance, of strains over-expressing broad range defensive mechanisms, such as efflux pumps. Second, since environmental species are provided with intrinsic antibiotic resistance mechanisms, the mixture with allochthonous species is likely to cause genetic exchange. In this context, the role of phages and integrons for the spread of resistance mechanisms appears significant. Allochthonous species could acquire new resistances from environmental donors and introduce the newly acquired resistance mechanisms into the clinics. This is illustrated by clinically relevant resistance mechanisms, such as the fluoroquinolones resistance genes qnr. Freshwater appears to play an important role in the emergence and in the spread of antibiotic resistances, highlighting the necessity for strategies of water quality improvement. Moreover, further knowledge is needed to better understand the role of the environment as reservoir of antibiotic resistances and to assess the risk of spread of antibiotic resistances via water bodies.

  3. Radiology of Fractures in Intoxicated Emergency Department Patients: Locations, Mechanisms, Presentation, and Initial Interpretation Accuracy.

    Science.gov (United States)

    Morita, Yuka; Nozaki, Taiki; Starkey, Jay; Okajima, Yuka; Ohde, Sachiko; Matsusako, Masaki; Yoshioka, Hiroshi; Saida, Yukihisa; Kurihara, Yasuyuki

    2015-06-01

    The purpose of this study was to investigate the relationship of alcohol intoxication to time-to-presentation following injury, fracture type, mechanism of injury leading to fracture, and initial diagnostic radiology interpretation performance of emergency physicians versus diagnostic radiologists in patients who present to the emergency department (ED) and are subsequently diagnosed with fracture. Medical records of 1286 patients who presented to the ED and were diagnosed with fracture who also underwent plain film or computed tomography (CT) imaging were retrospectively reviewed. The subjects were divided into intoxicated and sober groups. Patient characteristics, injury-to-presentation time, fracture location, and discrepancies between initial clinical and radiological evaluations were compared. Of 1286 subjects, 181 patients were included in the intoxicated group. Only intoxicated patients presented with head/neck fractures more than 24 hours after injury. The intoxicated group showed a higher rate of head/neck fractures (skull 23.2% vs 5.8%, face and orbit 30.4% vs 9.5%; P spinal fractures during this period. Alcohol-related injuries are more often associated with head/neck fractures but less extremity injuries. The rate of fractures missed by emergency physicians but later diagnosed by radiologists was the same in intoxicated and sober patients. PMID:26091471

  4. Buyanghuanwu decoction promotes angiogenesis after cerebral ischemia/reperfusion injury: mechanisms of brain tissue repair.

    Science.gov (United States)

    Zhang, Zhen-Qiang; Song, Jun-Ying; Jia, Ya-Quan; Zhang, Yun-Ke

    2016-03-01

    Buyanghuanwu decoction has been shown to protect against cerebral ischemia/reperfusion injury, but the underlying mechanisms remain unclear. In this study, rats were intragastrically given Buyanghuanwu decoction, 15 mL/kg, for 3 days. A rat model of cerebral ischemia/reperfusion injury was established by middle cerebral artery occlusion. In rats administered Buyanghuanwu decoction, infarct volume was reduced, serum vascular endothelial growth factor and integrin αvβ3 levels were increased, and brain tissue vascular endothelial growth factor and CD34 expression levels were increased compared with untreated animals. These effects of Buyanghuanwu decoction were partially suppressed by an angiogenesis inhibitor (administered through the lateral ventricle for 7 consecutive days). These data suggest that Buyanghuanwu decoction promotes angiogenesis, improves cerebral circulation, and enhances brain tissue repair after cerebral ischemia/reperfusion injury. PMID:27127482

  5. Buyanghuanwu decoction promotes angiogenesis after cerebral ischemia/reperfusion injury:mechanisms of brain tissue repair

    Institute of Scientific and Technical Information of China (English)

    Zhen-qiang Zhang; Jun-ying Song; Ya-quan Jia; Yun-ke Zhang

    2016-01-01

    Buyanghuanwu decoction has been shown to protect against cerebral ischemia/reperfusion injury, but the underlying mechanisms remain unclear. In this study, rats were intragastrically givenBuyanghuanwu decoction, 15 mL/kg, for 3 days. A rat model of cerebral ischemia/reper-fusion injury was established by middle cerebral artery occlusion. In rats administeredBuyanghuanwu decoction, infarct volume was reduced, serum vascular endothelial growth factor and integrinαvβ3 levels were increased, and brain tissue vascular endothelial growth factor and CD34 expression levels were increased compared with untreated animals. These effects ofBuyanghuanwu decoction were partially suppressed by an angiogenesis inhibitor (administered through the lateral ventricle for 7 consecutive days). These data suggest thatBuyanghuanwu de-coction promotes angiogenesis, improves cerebral circulation, and enhances brain tissue repair after cerebral ischemia/reperfusion injury.

  6. Buyanghuanwu decoction promotes angiogenesis after cerebral ischemia/reperfusion injury: mechanisms of brain tissue repair

    Directory of Open Access Journals (Sweden)

    Zhen-qiang Zhang

    2016-01-01

    Full Text Available Buyanghuanwu decoction has been shown to protect against cerebral ischemia/reperfusion injury, but the underlying mechanisms remain unclear. In this study, rats were intragastrically given Buyanghuanwu decoction, 15 mL/kg, for 3 days. A rat model of cerebral ischemia/reperfusion injury was established by middle cerebral artery occlusion. In rats administered Buyanghuanwu decoction, infarct volume was reduced, serum vascular endothelial growth factor and integrin αvβ3 levels were increased, and brain tissue vascular endothelial growth factor and CD34 expression levels were increased compared with untreated animals. These effects of Buyanghuanwu decoction were partially suppressed by an angiogenesis inhibitor (administered through the lateral ventricle for 7 consecutive days. These data suggest that Buyanghuanwu decoction promotes angiogenesis, improves cerebral circulation, and enhances brain tissue repair after cerebral ischemia/reperfusion injury.

  7. Molecular mechanisms of appetite and obesity: a role for brain AMPK.

    Science.gov (United States)

    Martínez de Morentin, Pablo B; Urisarri, Adela; Couce, María L; López, Miguel

    2016-10-01

    Feeding behaviour and energy storage are both crucial aspects of survival. Thus, it is of fundamental importance to understand the molecular mechanisms regulating these basic processes. The AMP-activated protein kinase (AMPK) has been revealed as one of the key molecules modulating energy homoeostasis. Indeed, AMPK appears to be essential for translating nutritional and energy requirements into generation of an adequate neuronal response, particularly in two areas of the brain, the hypothalamus and the hindbrain. Failure of this physiological response can lead to energy imbalance, ultimately with extreme consequences, such as leanness or obesity. Here, we will review the data that put brain AMPK in the spotlight as a regulator of appetite. PMID:27555613

  8. Equilibration, thermalisation, and the emergence of statistical mechanics in closed quantum systems

    Science.gov (United States)

    Gogolin, Christian; Eisert, Jens

    2016-05-01

    We review selected advances in the theoretical understanding of complex quantum many-body systems with regard to emergent notions of quantum statistical mechanics. We cover topics such as equilibration and thermalisation in pure state statistical mechanics, the eigenstate thermalisation hypothesis, the equivalence of ensembles, non-equilibration dynamics following global and local quenches as well as ramps. We also address initial state independence, absence of thermalisation, and many-body localisation. We elucidate the role played by key concepts for these phenomena, such as Lieb-Robinson bounds, entanglement growth, typicality arguments, quantum maximum entropy principles and the generalised Gibbs ensembles, and quantum (non-)integrability. We put emphasis on rigorous approaches and present the most important results in a unified language.

  9. Mechanisms of team-sport-related brain injuries in children 5 to 19 years old: opportunities for prevention.

    Directory of Open Access Journals (Sweden)

    Michael D Cusimano

    Full Text Available BACKGROUND: There is a gap in knowledge about the mechanisms of sports-related brain injuries. The objective of this study was to determine the mechanisms of brain injuries among children and youth participating in team sports. METHODS: We conducted a retrospective case series of brain injuries suffered by children participating in team sports. The Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP database was searched for brain injury cases among 5-19 year-olds playing ice hockey, soccer, American football (football, basketball, baseball, or rugby between 1990 and 2009. Mechanisms of injury were classified as "struck by player," "struck by object," "struck by sport implement," "struck surface," and "other." A descriptive analysis was performed. RESULTS: There were 12,799 brain injuries related to six team sports (16.2% of all brain injuries registered in CHIRPP. Males represented 81% of injuries and the mean age was 13.2 years. Ice hockey accounted for the greatest number of brain injuries (44.3%, followed by soccer (19.0% and football (12.9%. In ice hockey, rugby, and basketball, striking another player was the most common injury mechanism. Football, basketball, and soccer also demonstrated high proportions of injuries due to contact with an object (e.g., post among younger players. In baseball, a common mechanism in the 5-9 year-old group was being hit with a bat as a result of standing too close to the batter (26.1% males, 28.3% females. INTERPRETATION: Many sports-related brain injury mechanisms are preventable. The results suggest that further efforts aimed at universal rule changes, safer playing environments, and the education of coaches, players, and parents should be targeted in maximizing prevention of sport-related brain injury using a multifaceted approach.

  10. Mechanism of noradrenaline-induced stimulation of Na-K ATPase activity in the rat brain: implications on REM sleep deprivation-induced increase in brain excitability.

    Science.gov (United States)

    Mallick, Birendra Nath; Singh, Sudhuman; Singh, Abhishek

    2010-03-01

    Rapid eye movement (REM) sleep is a unique phenomenon expressed in all higher forms of animals. Its quantity varies in different species and with ageing; it is also affected in several psycho-somatic disorders. Several lines of studies showed that after REM sleep loss, the levels of noradrenaline (NA) increase in the brain. The NA in the brain modulates neuronal Na-K ATPase activity, which helps maintaining the brain excitability status. The detailed mechanism of increase in NA level after REM sleep loss and the effect of NA on stimulation of Na-K ATPase in the neurons have been discussed. The findings have been reviewed and discussed with an aim to understand the role of REM sleep in maintaining brain excitability status.

  11. On the physics of the emergence of sensorimotor control in the absence of the brain.

    Science.gov (United States)

    Matsuno, Koichiro

    2015-12-01

    The evolutionary origin of sensorimotor control requires a sort of physical durability, other than Galilean inertia being accessible in third-person description in the present tense. One candidate to address this need is the 'class property' of a material body's durability remaining invariant during the exchange of component elements. Using grammatical tense as a descriptive attribute, this durability is accessible only in the frequent update of the present perfect tense in the present progressive tense at the 'now' of the present moment. In this view, the update of the perfect tense is equated with the onset and occurrence of on/off switching behavior of physical origin underlying the phenomena of sensorimotor control. Notably, the physical update of the perfect tense is specific only to the 'now and here' that is central in the tradition of phenomenology. The phenomena upholding thermodynamics, when taken apart from its theory, are decisive in facilitating the onset of sensorimotor control. Instrumental to the emergence of both life in general and sensorimotor control in particular may be the occurrence of a 'physical and chemical affinity' of the material bodies of whatever type. Such will let the constant exchange of component elements be feasible, so that the class identity equipped with the capacity for measurement is made available within the phenomenon. Material bodies constantly exchanging such component elements would make the material world open to biology by allowing each element to experience the organizational whole from within. The internal observer responsible for the origins of life may do double duty of letting itself be durable on the material basis while observing the conditions making it durable on the linguistic ground. The origins of life appear to us a material phenomenon when they are approached with use of our linguistic tools that can get rid of the strict stipulation of an abstract nature applied to the description of dynamical laws in

  12. Brain Alterations and Clinical Symptoms of Dementia in Diabetes: Aβ/Tau-Dependent and Independent Mechanisms

    OpenAIRE

    NaoyukiSato

    2014-01-01

    Emerging evidence suggests that diabetes affects cognitive function and increases the incidence of dementia. However, the mechanisms by which diabetes modifies cognitive function still remains unclear. Morphologically, diabetes is associated with neuronal loss in the frontal and temporal lobes including the hippocampus, and aberrant functional connectivity of the posterior cingulate cortex and medial frontal/temporal gyrus. Clinically, diabetic patients show decreased executive function, info...

  13. Neuroprotective mechanism of the novel melatonin derivative Neu-P11 in brain ischemia related models.

    Science.gov (United States)

    Buendia, Izaskun; Gómez-Rangel, Vanessa; González-Lafuente, Laura; Parada, Esther; León, Rafael; Gameiro, Isabel; Michalska, Patrycja; Laudon, Moshe; Egea, Javier; López, Manuela G

    2015-12-01

    Stopping the ischemic cascade by targeting its components is a potential strategy for acute ischemic stroke treatment. During ischemia and especially over reperfusion, oxidative stress plays a major role in causing neuronal cell death. Melatonin has been previously reported to provide neuroprotective effects in in vivo models of stroke by a mechanism that implicates melatonin receptors. In this context, this study was planned to test the potential neuroprotective effects of the novel melatonin MT1/MT2 receptor agonist, Neu-P11, against brain ischemia in in vitro and in vivo models, and to elucidate its underlying mechanism of action. Neu-P11 proved to be a good antioxidant, to protect against glutamate-induced excitotoxicity and oxygen and glucose deprivation in hippocampal slices, and to reduce infarct volume in an in vivo stroke model. Regarding its mechanism of action, the protective effect of Neu-P11 was reverted by luzindole (melatonin receptor antagonist), AG490 (JAK2 inhibitor), LY294002 (PI3/AKT inhibitor) and PD98059 (MEK/ERK1/2 inhibitor). In conclusion, Neu-P11 affords neuroprotection against brain ischemia in in vitro and in vivo models by activating a pro-survival signaling pathway that involves melatonin receptors, JAK/STAT, PI3K/Akt and MEK/ERK1/2.

  14. 面向突发事件的应急财政保障机制研究%Security Mechanism of Emergency Finance for Emergencies

    Institute of Scientific and Technical Information of China (English)

    李亘; 李向阳; 孙钦莹

    2014-01-01

    Various types of emergencies occur frequently in our country. Under the control of government, emergency finance department protects public property and interests, thus the emergency fiscal has the extremely important status and plays a significant role in the emergency management. According to the existing problems in our country, it is necessary to strengthen emergency management and supervision during the preparatory phase, response phase and recovery phase. On this basis, the security mechanism of emergency finance is set up, including the financial mechanism of warning and preventing, the financial mechanism of emergency disposal, the financial mechanism of restoration and reconstruction, operating mechanism and supervision mechanism, in order to save people’ awareness and preventive measures.%各类型的突发事件在我国时有发生,应急财政在政府的调控下,维护公众的财产和利益,由此可见应急财政在应急管理中具有极其重要的地位和作用。针对我国应急财政现存的问题,必须强化应急资金在灾前、灾中、灾后的管理与监督,并根据突发事件应急管理的三个阶段(准备阶段、响应阶段、恢复阶段)分别构建预警防范财政保障机制、应急处置财政保障机制、恢复重建财政保障机制,以及贯穿应急管理全过程的应急财政运行机制与应急财政监督机制,形成整体的应急财政保障机制,提醒政府与人民如何提高自救意识与防范措施。

  15. Brain IGF-1 receptors control mammalian growth and lifespan through a neuroendocrine mechanism.

    Directory of Open Access Journals (Sweden)

    Laurent Kappeler

    2008-10-01

    Full Text Available Mutations that decrease insulin-like growth factor (IGF and growth hormone signaling limit body size and prolong lifespan in mice. In vertebrates, these somatotropic hormones are controlled by the neuroendocrine brain. Hormone-like regulations discovered in nematodes and flies suggest that IGF signals in the nervous system can determine lifespan, but it is unknown whether this applies to higher organisms. Using conditional mutagenesis in the mouse, we show that brain IGF receptors (IGF-1R efficiently regulate somatotropic development. Partial inactivation of IGF-1R in the embryonic brain selectively inhibited GH and IGF-I pathways after birth. This caused growth retardation, smaller adult size, and metabolic alterations, and led to delayed mortality and longer mean lifespan. Thus, early changes in neuroendocrine development can durably modify the life trajectory in mammals. The underlying mechanism appears to be an adaptive plasticity of somatotropic functions allowing individuals to decelerate growth and preserve resources, and thereby improve fitness in challenging environments. Our results also suggest that tonic somatotropic signaling entails the risk of shortened lifespan.

  16. Mechanisms of 5-azacytidine (5AzC)-induced toxicity in the rat foetal brain

    Science.gov (United States)

    Ueno, Masaki; Katayama, Kei-Ichi; Nakayama, Hiroyuki; Doi, Kunio

    2002-01-01

    Mechanisms of 5-azacytidine (5AzC)-induced toxicity in the rat foetal brain were investigated. 5AzC (10 mg/kg) was injected into pregnant rats on day 13 of gestation and the protein and mRNA expressions of p53 and its transcriptional target genes, p21, bax, cyclin G1, fas, and gadd45, were examined in the foetal brain. The number of p53-positive cells peaked at 9 h after treatment (HAT) and those of apoptotic cells and p21-positive cells peaked at 12 HAT. The expressions of p21, bax, cyclin G1, and fas mRNAs were significantly elevated from 9 to 12 HAT. From the experiments using 5-bromo-2′-deoxyuridine (BrdU), as compared with controls, the migration of neuroepithelial cells significantly delayed and BrdU-positive signals were observed in many apoptotic cells from 9 to 24 HAT in the 5AzC-group. In addition, the number of S phase cells significantly decreased at 12 HAT. The present results indicate that 5AzC induced apoptosis and cell cycle arrest probably at G1 phase in the rat foetal brain and they might be mediated by p53 in response to DNA damage. PMID:12383193

  17. Brain Mechanisms for Processing Affective (and Nonaffective) Touch Are Atypical in Autism.

    Science.gov (United States)

    Kaiser, Martha D; Yang, Daniel Y-J; Voos, Avery C; Bennett, Randi H; Gordon, Ilanit; Pretzsch, Charlotte; Beam, Danielle; Keifer, Cara; Eilbott, Jeffrey; McGlone, Francis; Pelphrey, Kevin A

    2016-06-01

    C-tactile (CT) afferents encode caress-like touch that supports social-emotional development, and stimulation of the CT system engages the insula and cortical circuitry involved in social-emotional processing. Very few neuroimaging studies have investigated the neural mechanisms of touch processing in people with autism spectrum disorder (ASD), who often exhibit atypical responses to touch. Using functional magnetic resonance imaging, we evaluated the hypothesis that children and adolescents with ASD would exhibit atypical brain responses to CT-targeted touch. Children and adolescents with ASD, relative to typically developing (TD) participants, exhibited reduced activity in response to CT-targeted (arm) versus non-CT-targeted (palm) touch in a network of brain regions known to be involved in social-emotional information processing including bilateral insula and insular operculum, the right posterior superior temporal sulcus, bilateral temporoparietal junction extending into the inferior parietal lobule, right fusiform gyrus, right amygdala, and bilateral ventrolateral prefrontal cortex including the inferior frontal and precentral gyri, suggesting atypical social brain hypoactivation. Individuals with ASD (vs. TD) showed an enhanced response to non-CT-targeted versus CT-targeted touch in the primary somatosensory cortex, suggesting atypical sensory cortical hyper-reactivity. PMID:26048952

  18. Estradiol decreases cortical reactive astrogliosis after brain injury by a mechanism involving cannabinoid receptors.

    Science.gov (United States)

    López Rodríguez, Ana Belén; Mateos Vicente, Beatriz; Romero-Zerbo, Silvana Y; Rodriguez-Rodriguez, Noé; Bellini, María José; Rodriguez de Fonseca, Fernando; Bermudez-Silva, Francisco Javier; Azcoitia, Iñigo; Garcia-Segura, Luis M; Viveros, María-Paz

    2011-09-01

    The neuroactive steroid estradiol reduces reactive astroglia after brain injury by mechanisms similar to those involved in the regulation of reactive gliosis by endocannabinoids. In this study, we have explored whether cannabinoid receptors are involved in the effects of estradiol on reactive astroglia. To test this hypothesis, the effects of estradiol, the cannabinoid CB1 antagonist/inverse agonist AM251, and the cannabinoid CB2 antagonist/inverse agonist AM630 were assessed in the cerebral cortex of male rats after a stab wound brain injury. Estradiol reduced the number of vimentin immunoreactive astrocytes and the number of glial fibrillary acidic protein immunoreactive astrocytes in the proximity of the wound. The effect of estradiol was significantly inhibited by the administration of either CB1 or CB2 receptor antagonists. The effect of estradiol may be in part mediated by alterations in endocannabinoid signaling because the hormone increased in the injured cerebral cortex the messenger RNA levels of CB2 receptors and of some of the enzymes involved in the synthesis and metabolism of endocannabinoids. These findings suggest that estradiol may decrease reactive astroglia in the injured brain by regulating the activity of the endocannabinoid system.

  19. Stem cell therapy to protect and repair the developing brain: a review of mechanisms of action of cord blood and amnion epithelial derived cells.

    Science.gov (United States)

    Castillo-Melendez, Margie; Yawno, Tamara; Jenkin, Graham; Miller, Suzanne L

    2013-10-24

    In the research, clinical, and wider community there is great interest in the use of stem cells to reduce the progression, or indeed repair brain injury. Perinatal brain injury may result from acute or chronic insults sustained during fetal development, during the process of birth, or in the newborn period. The most readily identifiable outcome of perinatal brain injury is cerebral palsy, however, this is just one consequence in a spectrum of mild to severe neurological deficits. As we review, there are now clinical trials taking place worldwide targeting cerebral palsy with stem cell therapies. It will likely be many years before strong evidence-based results emerge from these trials. With such trials underway, it is both appropriate and timely to address the physiological basis for the efficacy of stem-like cells in preventing damage to, or regenerating, the newborn brain. Appropriate experimental animal models are best placed to deliver this information. Cell availability, the potential for immunological rejection, ethical, and logistical considerations, together with the propensity for native cells to form teratomas, make it unlikely that embryonic or fetal stem cells will be practical. Fortunately, these issues do not pertain to the use of human amnion epithelial cells (hAECs), or umbilical cord blood (UCB) stem cells that are readily and economically obtained from the placenta and umbilical cord discarded at birth. These cells have the potential for transplantation to the newborn where brain injury is diagnosed or even suspected. We will explore the novel characteristics of hAECs and undifferentiated UCB cells, as well as UCB-derived endothelial progenitor cells (EPCs) and mesenchymal stem cells (MSCs), and how immunomodulation and anti-inflammatory properties are principal mechanisms of action that are common to these cells, and which in turn may ameliorate the cerebral hypoxia and inflammation that are final pathways in the pathogenesis of perinatal brain

  20. Stem cell therapy to protect and repair the developing brain: a review of mechanisms of action of cord blood and amnion epithelial derived cells

    Directory of Open Access Journals (Sweden)

    Margie eCastillo-Melendez

    2013-10-01

    Full Text Available In the research, clinical and wider community there is great interest in the use of stem cells to reduce the progression, or indeed repair brain injury. Perinatal brain injury may result from acute or chronic insults sustained during fetal development, during the process of birth, or in the newborn period. The most readily identifiable outcome of perinatal brain injury is cerebral palsy, however this is just one consequence in a spectrum of mild to severe neurological deficits. As we review, there are now clinical trials taking place worldwide targeting cerebral palsy with stem cell therapies. It will likely be many years before strong evidence-based results emerge from these trials. With such trials underway, it is both appropriate and timely to address the physiological basis for the efficacy of stem-like cells in preventing damage to, or regenerating, the newborn brain. Appropriate experimental animal models are best placed to deliver this information. Cell availability, the potential for immunological rejection, ethical and logistical considerations, together with the propensity for native cells to form terratomas, make it unlikely that embryonic or fetal stem cells will be practical. Fortunately, these issues do not pertain to the use of human amnion epithelial cells (hAECs, or umbilical cord blood (UCB stem cells that are readily and economically obtained from the placenta and umbilical cord discarded at birth. These cells have the potential for transplantation to the newborn where brain injury is diagnosed or even suspected. We will explore the novel characteristics of hAECs and undifferentiated UCB cells, as well as UCB-derived endothelial progenitor cells and mesenchymal stem cells, and how immunomodulation and anti-inflammatory properties are principal mechanisms of action that are common to these cells, and which in turn may ameliorate the cerebral hypoxia and inflammation that are final pathways in the pathogenesis of perinatal brain

  1. Hydrogen bond networks determine emergent mechanical and thermodynamic properties across a protein family

    Directory of Open Access Journals (Sweden)

    Dallakyan Sargis

    2008-08-01

    Full Text Available Abstract Background Gram-negative bacteria use periplasmic-binding proteins (bPBP to transport nutrients through the periplasm. Despite immense diversity within the recognized substrates, all members of the family share a common fold that includes two domains that are separated by a conserved hinge. The hinge allows the protein to cycle between open (apo and closed (ligated conformations. Conformational changes within the proteins depend on a complex interplay of mechanical and thermodynamic response, which is manifested as an increase in thermal stability and decrease of flexibility upon ligand binding. Results We use a distance constraint model (DCM to quantify the give and take between thermodynamic stability and mechanical flexibility across the bPBP family. Quantitative stability/flexibility relationships (QSFR are readily evaluated because the DCM links mechanical and thermodynamic properties. We have previously demonstrated that QSFR is moderately conserved across a mesophilic/thermophilic RNase H pair, whereas the observed variance indicated that different enthalpy-entropy mechanisms allow similar mechanical response at their respective melting temperatures. Our predictions of heat capacity and free energy show marked diversity across the bPBP family. While backbone flexibility metrics are mostly conserved, cooperativity correlation (long-range couplings also demonstrate considerable amount of variation. Upon ligand removal, heat capacity, melting point, and mechanical rigidity are, as expected, lowered. Nevertheless, significant differences are found in molecular cooperativity correlations that can be explained by the detailed nature of the hydrogen bond network. Conclusion Non-trivial mechanical and thermodynamic variation across the family is explained by differences within the underlying H-bond networks. The mechanism is simple; variation within the H-bond networks result in altered mechanical linkage properties that directly affect

  2. Mechanical characterization of brain tissue in compression at dynamic strain rates.

    Science.gov (United States)

    Rashid, Badar; Destrade, Michel; Gilchrist, Michael D

    2012-06-01

    Traumatic brain injury (TBI) occurs when local mechanical load exceeds certain tolerance levels for brain tissue. Extensive research has been done previously for brain matter experiencing compression at quasistatic loading; however, limited data is available to model TBI under dynamic impact conditions. In this research, an experimental setup was developed to perform unconfined compression tests and stress relaxation tests at strain rates ≤90/s. The brain tissue showed a stiffer response with increasing strain rates, showing that hyperelastic models are not adequate. Specifically, the compressive nominal stress at 30% strain was 8.83 ± 1.94, 12.8 ± 3.10 and 16.0 ± 1.41 kPa (mean ± SD) at strain rates of 30, 60 and 90/s, respectively. Relaxation tests were also conducted at 10%-50% strain with the average rise time of 10 ms, which can be used to derive time dependent parameters. Numerical simulations were performed using one-term Ogden model with initial shear modulus μ(o)=6.06±1.44, 9.44 ± 2.427 and 12.64 ± 1.227 kPa (mean ± SD) at strain rates of 30, 60 and 90/s, respectively. A separate set of bonded and lubricated tests were also performed under the same test conditions to estimate the friction coefficient μ, by adopting combined experimental-computational approach. The values of μ were 0.1 ± 0.03 and 0.15 ± 0.07 (mean ± SD) at 30 and 90/s strain rates, respectively, indicating that pure slip conditions cannot be achieved in unconfined compression tests even under fully lubricated test conditions. The material parameters obtained in this study will help to develop biofidelic human brain finite element models, which can subsequently be used to predict brain injuries under impact conditions. PMID:22520416

  3. Observation of direction-dependent mechanical properties in the human brain with multi-excitation MR elastography.

    Science.gov (United States)

    Anderson, Aaron T; Van Houten, Elijah E W; McGarry, Matthew D J; Paulsen, Keith D; Holtrop, Joseph L; Sutton, Bradley P; Georgiadis, John G; Johnson, Curtis L

    2016-06-01

    Magnetic resonance elastography (MRE) has shown promise in noninvasively capturing changes in mechanical properties of the human brain caused by neurodegenerative conditions. MRE involves vibrating the brain to generate shear waves, imaging those waves with MRI, and solving an inverse problem to determine mechanical properties. Despite the known anisotropic nature of brain tissue, the inverse problem in brain MRE is based on an isotropic mechanical model. In this study, distinct wave patterns are generated in the brain through the use of multiple excitation directions in order to characterize the potential impact of anisotropic tissue mechanics on isotropic inversion methods. Isotropic inversions of two unique displacement fields result in mechanical property maps that vary locally in areas of highly aligned white matter. Investigation of the corpus callosum, corona radiata, and superior longitudinal fasciculus, three highly ordered white matter tracts, revealed differences in estimated properties between excitations of up to 33%. Using diffusion tensor imaging to identify dominant fiber orientation of bundles, relationships between estimated isotropic properties and shear asymmetry are revealed. This study has implications for future isotropic and anisotropic MRE studies of white matter tracts in the human brain. PMID:27032311

  4. Inflammation triggers emergency granulopoiesis through a density-dependent feedback mechanism.

    Directory of Open Access Journals (Sweden)

    Derek W Cain

    Full Text Available Normally, neutrophil pools are maintained by homeostatic mechanisms that require the transcription factor C/EBPα. Inflammation, however, induces neutrophilia through a distinct pathway of "emergency" granulopoiesis that is dependent on C/EBPβ. Here, we show in mice that alum triggers emergency granulopoiesis through the IL-1RI-dependent induction of G-CSF. G-CSF/G-CSF-R neutralization impairs proliferative responses of hematopoietic stem and progenitor cells (HSPC to alum, but also abrogates the acute mobilization of BM neutrophils, raising the possibility that HSPC responses to inflammation are an indirect result of the exhaustion of BM neutrophil stores. The induction of neutropenia, via depletion with Gr-1 mAb or myeloid-specific ablation of Mcl-1, elicits G-CSF via an IL-1RI-independent pathway, stimulating granulopoietic responses indistinguishable from those induced by adjuvant. Notably, C/EBPβ, thought to be necessary for enhanced generative capacity of BM, is dispensable for increased proliferation of HSPC to alum or neutropenia, but plays a role in terminal neutrophil differentiation during granulopoietic recovery. We conclude that alum elicits a transient increase in G-CSF production via IL-1RI for the mobilization of BM neutrophils, but density-dependent feedback sustains G-CSF for accelerated granulopoiesis.

  5. Paralog re-emergence: a novel, historically contingent mechanism in the evolution of antimicrobial resistance.

    Science.gov (United States)

    Hawkins, Nichola J; Cools, Hans J; Sierotzki, Helge; Shaw, Michael W; Knogge, Wolfgang; Kelly, Steven L; Kelly, Diane E; Fraaije, Bart A

    2014-07-01

    Evolution of resistance to drugs and pesticides poses a serious threat to human health and agricultural production. CYP51 encodes the target site of azole fungicides, widely used clinically and in agriculture. Azole resistance can evolve due to point mutations or overexpression of CYP51, and previous studies have shown that fungicide-resistant alleles have arisen by de novo mutation. Paralogs CYP51A and CYP51B are found in filamentous ascomycetes, but CYP51A has been lost from multiple lineages. Here, we show that in the barley pathogen Rhynchosporium commune, re-emergence of CYP51A constitutes a novel mechanism for the evolution of resistance to azoles. Pyrosequencing analysis of historical barley leaf samples from a unique long-term experiment from 1892 to 2008 indicates that the majority of the R. commune population lacked CYP51A until 1985, after which the frequency of CYP51A rapidly increased. Functional analysis demonstrates that CYP51A retains the same substrate as CYP51B, but with different transcriptional regulation. Phylogenetic analyses show that the origin of CYP51A far predates azole use, and newly sequenced Rhynchosporium genomes show CYP51A persisting in the R. commune lineage rather than being regained by horizontal gene transfer; therefore, CYP51A re-emergence provides an example of adaptation to novel compounds by selection from standing genetic variation.

  6. Functional Mechanisms of Recovery after Chronic Stroke: Modeling with the Virtual Brain.

    Science.gov (United States)

    Falcon, Maria Inez; Riley, Jeffrey D; Jirsa, Viktor; McIntosh, Anthony R; Chen, E Elinor; Solodkin, Ana

    2016-01-01

    We have seen important strides in our understanding of mechanisms underlying stroke recovery, yet effective translational links between basic and applied sciences, as well as from big data to individualized therapies, are needed to truly develop a cure for stroke. We present such an approach using The Virtual Brain (TVB), a neuroinformatics platform that uses empirical neuroimaging data to create dynamic models of an individual's human brain; specifically, we simulate fMRI signals by modeling parameters associated with brain dynamics after stroke. In 20 individuals with stroke and 11 controls, we obtained rest fMRI, T1w, and diffusion tensor imaging (DTI) data. Motor performance was assessed pre-therapy, post-therapy, and 6-12 months post-therapy. Based on individual structural connectomes derived from DTI, the following steps were performed in the TVB platform: (1) optimization of local and global parameters (conduction velocity, global coupling); (2) simulation of BOLD signal using optimized parameter values; (3) validation of simulated time series by comparing frequency, amplitude, and phase of the simulated signal with empirical time series; and (4) multivariate linear regression of model parameters with clinical phenotype. Compared with controls, individuals with stroke demonstrated a consistent reduction in conduction velocity, increased local dynamics, and reduced local inhibitory coupling. A negative relationship between local excitation and motor recovery, and a positive correlation between local dynamics and motor recovery were seen. TVB reveals a disrupted post-stroke system favoring excitation-over-inhibition and local-over-global dynamics, consistent with existing mammal literature on stroke mechanisms. Our results point to the potential of TVB to determine individualized biomarkers of stroke recovery. PMID:27088127

  7. Acute Modulation of Brain Connectivity in Parkinson Disease after Automatic Mechanical Peripheral Stimulation: A Pilot Study.

    Directory of Open Access Journals (Sweden)

    Carlo Cosimo Quattrocchi

    Full Text Available The present study shows the results of a double-blind sham-controlled pilot trial to test whether measurable stimulus-specific functional connectivity changes exist after Automatic Mechanical Peripheral Stimulation (AMPS in patients with idiopathic Parkinson Disease.Eleven patients (6 women and 5 men with idiopathic Parkinson Disease underwent brain fMRI immediately before and after sham or effective AMPS. Resting state Functional Connectivity (RSFC was assessed using the seed-ROI based analysis. Seed ROIs were positioned on basal ganglia, on primary sensory-motor cortices, on the supplementary motor areas and on the cerebellum. Individual differences for pre- and post-effective AMPS and pre- and post-sham condition were obtained and first entered in respective one-sample t-test analyses, to evaluate the mean effect of condition.Effective AMPS, but not sham stimulation, induced increase of RSFC of the sensory motor cortex, nucleus striatum and cerebellum. Secondly, individual differences for both conditions were entered into paired group t-test analysis to rule out sub-threshold effects of sham stimulation, which showed stronger connectivity of the striatum nucleus with the right lateral occipital cortex and the cuneal cortex (max Z score 3.12 and with the right anterior temporal lobe (max Z score 3.42 and of the cerebellum with the right lateral occipital cortex and the right cerebellar cortex (max Z score 3.79.Our results suggest that effective AMPS acutely increases RSFC of brain regions involved in visuo-spatial and sensory-motor integration.This study provides Class II evidence that automatic mechanical peripheral stimulation is effective in modulating brain functional connectivity of patients with Parkinson Disease at rest.Clinical Trials.gov NCT01815281.

  8. Neurophysiological Evidence of Compensatory Brain Mechanisms in Early-Stage Multiple Sclerosis

    Science.gov (United States)

    López-Góngora, Mariana; Escartín, Antonio; Martínez-Horta, Saul; Fernández-Bobadilla, Ramón; Querol, Luis; Romero, Sergio; Mañanas, Miquel Àngel; Riba, Jordi

    2015-01-01

    Multiple sclerosis (MS) is a chronic central nervous system disorder characterized by white matter inflammation, demyelination and neurodegeneration. Although cognitive dysfunction is a common manifestation, it may go unnoticed in recently-diagnosed patients. Prior studies suggest MS patients develop compensatory mechanisms potentially involving enhanced performance monitoring. Here we assessed the performance monitoring system in early-stage MS patients using the error-related negativity (ERN), an event-related brain potential (ERP) observed following behavioral errors. Twenty-seven early-stage MS patients and 31 controls were neuropsychologically assessed. Electroencephalography recordings were obtained while participants performed: a) a stop task and b) an auditory oddball task. Behavior and ERP measures were assessed. No differences in performance were found between groups in most neuropsychological tests or in behavior or ERP components in the auditory oddball task. However, the amplitude of the ERN associated with stop errors in the stop task was significantly higher in patients. ERN amplitude correlated positively with scores on the Expanded Disability Status Scale and the Multiple Sclerosis Severity Score, and negatively with the time since last relapse. Patients showed higher neuronal recruitment in tasks involving performance monitoring. Results suggest the development of compensatory brain mechanisms in early-stage MS and reflect the sensitivity of the ERN to detect these changes. PMID:26322632

  9. Brain mechanisms that underlie the effects of motivational audiovisual stimuli on psychophysiological responses during exercise.

    Science.gov (United States)

    Bigliassi, Marcelo; Silva, Vinícius B; Karageorghis, Costas I; Bird, Jonathan M; Santos, Priscila C; Altimari, Leandro R

    2016-05-01

    Motivational audiovisual stimuli such as music and video have been widely used in the realm of exercise and sport as a means by which to increase situational motivation and enhance performance. The present study addressed the mechanisms that underlie the effects of motivational stimuli on psychophysiological responses and exercise performance. Twenty-two participants completed fatiguing isometric handgrip-squeezing tasks under two experimental conditions (motivational audiovisual condition and neutral audiovisual condition) and a control condition. Electrical activity in the brain and working muscles was analyzed by use of electroencephalography and electromyography, respectively. Participants were asked to squeeze the dynamometer maximally for 30s. A single-item motivation scale was administered after each squeeze. Results indicated that task performance and situational motivational were superior under the influence of motivational stimuli when compared to the other two conditions (~20% and ~25%, respectively). The motivational stimulus downregulated the predominance of low-frequency waves (theta) in the right frontal regions of the cortex (F8), and upregulated high-frequency waves (beta) in the central areas (C3 and C4). It is suggested that motivational sensory cues serve to readjust electrical activity in the brain; a mechanism by which the detrimental effects of fatigue on the efferent control of working muscles is ameliorated. PMID:26948160

  10. Infusion of Emerging Technologies and New Teaching Methods into the Mechanical Engineering Curriculum at the City College of New York

    Science.gov (United States)

    Delale, Feridun; Liaw, Benjamin M.; Jiji, Latif M.; Voiculescu, Ioana; Yu, Honghui

    2011-01-01

    From October 2003 to April 2008 a systemic reform of the Mechanical Engineering program at The City College of New York was undertaken with the goal of incorporating emerging technologies (such as nanotechnology, biotechnology, Micro-Electro-Mechanical Systems (MEMS), intelligent systems) and new teaching methodologies (such as project based…

  11. Prediction of brain target site concentrations on the basis of CSF PK : impact of mechanisms of blood-to-brain transport and within brain distribution

    NARCIS (Netherlands)

    Westerhout, Joost

    2014-01-01

    In the development of drugs for the treatment of central nervous system (CNS) disorders, the prediction of human CNS drug action is a big challenge. Direct measurement of brain extracellular fluid (brainECF) concentrations is highly restricted in human. Therefore, unbound drug concentrations in huma

  12. Early self-reproduction, the emergence of division mechanisms in protocells.

    Science.gov (United States)

    Murtas, Giovanni

    2013-02-01

    Synthetic Biology approaches are proposing model systems and providing experimental evidences that life can arise as spontaneous chemical self-assembly process where the ability to reproduce itself is an essential feature of the living system. The appearance of early cells has required an amphiphilic membrane compartment to confine molecular information against diffusion, and the ability to self-replicate the boundary layer and the genetic information. The initial spontaneous self-replication mechanisms based on thermodynamic instability would have evolved in a prebiotic and later biological catalysis. Early studies demonstrate that fatty acids spontaneously assemble into bilayer membranes, building vesicles able to grow by incorporation of free lipid molecules and divide. Early replication mechanisms may have seen inorganic molecules playing a role as the first catalysts. The emergence of a short ribozyme or short catalytic peptide may have initiated the first prebiotic membrane lipid synthesis required for vesicle growth. The evolution of early catalysts towards the simplest translation machine to deliver proteins from RNA sequences was likely to give early birth to one single enzyme controlling protocell membrane division. The cell replication process assisted by complex enzymes for lipid synthesis is the result of evolved pathways in early cells. Evolution from organic molecules to protocells and early cells, thus from chemistry to biology, may have occurred in and out of the boundary layer. Here we review recent experimental work describing membrane and vesicle division mechanisms based on chemico-physical spontaneous processes, inorganic early catalysis and enzyme based mechanisms controlling early protocell division and finally the feedback from minimal genome studies. PMID:23232904

  13. Interactions between connected half-sarcomeres produce emergent mechanical behavior in a mathematical model of muscle.

    Directory of Open Access Journals (Sweden)

    Kenneth S Campbell

    2009-11-01

    Full Text Available Most reductionist theories of muscle attribute a fiber's mechanical properties to the scaled behavior of a single half-sarcomere. Mathematical models of this type can explain many of the known mechanical properties of muscle but have to incorporate a passive mechanical component that becomes approximately 300% stiffer in activating conditions to reproduce the force response elicited by stretching a fast mammalian muscle fiber. The available experimental data suggests that titin filaments, which are the mostly likely source of the passive component, become at most approximately 30% stiffer in saturating Ca2+ solutions. The work described in this manuscript used computer modeling to test an alternative systems theory that attributes the stretch response of a mammalian fiber to the composite behavior of a collection of half-sarcomeres. The principal finding was that the stretch response of a chemically permeabilized rabbit psoas fiber could be reproduced with a framework consisting of 300 half-sarcomeres arranged in 6 parallel myofibrils without requiring titin filaments to stiffen in activating solutions. Ablation of inter-myofibrillar links in the computer simulations lowered isometric force values and lowered energy absorption during a stretch. This computed behavior mimics effects previously observed in experiments using muscles from desmin-deficient mice in which the connections between Z-disks in adjacent myofibrils are presumably compromised. The current simulations suggest that muscle fibers exhibit emergent properties that reflect interactions between half-sarcomeres and are not properties of a single half-sarcomere in isolation. It is therefore likely that full quantitative understanding of a fiber's mechanical properties requires detailed analysis of a complete fiber system and cannot be achieved by focusing solely on the properties of a single half-sarcomere.

  14. Transient hypoxia stimulates mitochondrial biogenesis in brain subcortex by a neuronal nitric oxide synthase-dependent mechanism

    Science.gov (United States)

    The adaptive mechanisms that protect brain metabolism during and after hypoxia, for instance, during hypoxic preconditioning, are coordinated in part by nitric oxide (NO). We tested the hypothesis that acute transient hypoxia stimulates NO synthase (NOS)-activated mechanisms of m...

  15. Mechanism of Action of Ulipristal Acetate for Emergency Contraception: A Systematic Review.

    Science.gov (United States)

    Rosato, Elena; Farris, Manuela; Bastianelli, Carlo

    2015-01-01

    Ulipristal acetate (UPA) is now recommended as first choice hormonal emergency contraception (EC), due to its higher efficacy and similar safety compared to Levonorgestrel - EC. Even though all trials demonstrated that the first mechanism of action is inhibition of ovulation, some authors still postulate that a post fertilization effect is also possible, raising the alert on medication and fostering the ethical debate. A Medline database search was performed in order to find recent articles related to UPA's effects on ovulation, on fallopian tube and on endometrium. We also analyzed the effects on sperm function and pregnancy. All studies conclude that UPA is effective in inhibition of ovulation even when administered shortly before LH peak. The effects on fallopian tube are unclear: according to some authors UPA inhibits ciliar beat through an agonistic effect on progesterone receptors, according to others it antagonizes the progesterone-induced ciliar beat decrease. Concerning the action on endometrium and on embryo implantation most of the studies concluded that low dose UPA used for EC has no significant effect on the decrease of endometrial thickness and on embryo's attachment, but these results are still matter of debate. Finally recent evidence suggests that UPA modulates human sperm functions while it has no effect on established pregnancy. To date the majority of the evidence concurs in excluding a post-fertilization effect of UPA, even though more studies are needed to clarify its mechanism of action. PMID:26793107

  16. Mechanism of action of ulipristal acetate for emergency contraception: a systematic review

    Directory of Open Access Journals (Sweden)

    Elena eRosato

    2016-01-01

    Full Text Available SUMMARYUlipristal acetate (UPA is now recommended as first choice hormonal Emergency Contraception (EC, due to its higher efficacy and similar safety compared to Levonogestrel - EC. Even though all trials demonstrated that the first mechanism of action is inhibition of ovulation, some authors still postulate that a post fertilization effect is also possible, raising the alert on medication and fostering the ethical debate.A Medline database search was performed in order to find recent articles related to UPA’s effects on ovulation, on fallopian tube and on endometrium. We also analyzed the effects on sperm function and pregnancy. All studies conclude that UPA is effective in inhibition of ovulation even when administered shortly before LH peak. The effects on fallopian tube are unclear: according to some authors UPA inhibits ciliar beat through an agonistic effect on progesterone receptors, according to others it antagonizes the progesterone-induced ciliar beat decrease. Concerning the action on endometrium and on embryo implantation most of the studies concluded that low dose UPA used for EC has no significant effect on the decrease of endometrial thickness and on embryo’s attachment, but these results are still matter of debate. Finally recent evidence suggests that UPA modulates human sperm functions while it has no effect on established pregnancy. To date the majority of the evidence concur in excluding a post-fertilization effect of UPA, even though more studies are needed to clarify its mechanism of action.

  17. Mechanical circulatory assist devices: a primer for critical care and emergency physicians.

    Science.gov (United States)

    Sen, Ayan; Larson, Joel S; Kashani, Kianoush B; Libricz, Stacy L; Patel, Bhavesh M; Guru, Pramod K; Alwardt, Cory M; Pajaro, Octavio; Farmer, J Christopher

    2016-01-01

    Mechanical circulatory assist devices are now commonly used in the treatment of severe heart failure as bridges to cardiac transplant, as destination therapy for patients who are not transplant candidates, and as bridges to recovery and "decision-making". These devices, which can be used to support the left or right ventricles or both, restore circulation to the tissues, thereby improving organ function. Left ventricular assist devices (LVADs) are the most common support devices. To care for patients with these devices, health care providers in emergency departments (EDs) and intensive care units (ICUs) need to understand the physiology of the devices, the vocabulary of mechanical support, the types of complications patients may have, diagnostic techniques, and decision-making regarding treatment. Patients with LVADs who come to the ED or are admitted to the ICU usually have nonspecific clinical symptoms, most commonly shortness of breath, hypotension, anemia, chest pain, syncope, hemoptysis, gastrointestinal bleeding, jaundice, fever, oliguria and hematuria, altered mental status, headache, seizure, and back pain. Other patients are seen for cardiac arrest, psychiatric issues, sequelae of noncardiac surgery, and trauma. Although most patients have LVADs, some may have biventricular support devices or total artificial hearts. Involving a team of cardiac surgeons, perfusion experts, and heart-failure physicians, as well as ED and ICU physicians and nurses, is critical for managing treatment for these patients and for successful outcomes. This review is designed for critical care providers who may be the first to see these patients in the ED or ICU. PMID:27342573

  18. Recovery mechanisms of somatosensory function in stroke patients: implications of brain imaging studies

    Institute of Scientific and Technical Information of China (English)

    Sung Ho Jang

    2013-01-01

    Somatosensory dysfunction is associated with a high incidence of functional impairment and safety in patients with stroke.With developments in brain mapping techniques,many studies have addressed the recovery of various functions in such patients.However,relatively little is known about the mechanisms of recovery of somatosensory function.Based on the previous human studies,a review of 11 relevant studies on the mechanisms underlying the recovery of somatosensory function in stroke patients was conducted based on the following topics:(1) recovery of an injured somatosensory pathway,(2) peri-lesional reorganization,(3) contribution of the unaffected somatosensory cortex,(4) contribution of the secondary somatosensory cortex,and (5)mechanisms of recovery in patients with thalamic lesions.We believe that further studies in this field using combinations of diffusion tensor imaging,functional neuroimaging,and magnetoencephalography are needed.In addition,the clinical significance,critical period,and facilitatory strategies for each recovery mechanism should be clarified.

  19. A Tentative Mechanism of Solubilization of Neuropathy Target Esterase from Chicken Embryo Brain by Phospholipase A2

    Directory of Open Access Journals (Sweden)

    Josef Seifert

    2008-01-01

    Full Text Available The neuropathy target esterase is a membrane-bound enzyme linked to organophosphate-induced distal neuropathy. Here we report a tentative mechanism of its solubilization from chicken embryo brains by using phospholipase A2. The enzyme was released from brain membranes after degradation of their structural phospholipids initiated by phospholipase A2. L-α-lysophosphatidylcholine, tested as a representative product of phospholipid hydrolysis, was identified as a new efficient detergent for solubilization of the neuropathy target esterase.

  20. Is there a better commitment mechanism than cross-listings for emerging-economy firms? Evidence from Mexico

    OpenAIRE

    Jordan Siegel

    2009-01-01

    The last decade of work in corporate governance has shown that weak legal institutions at the country level hinder firms in emerging economies from accessing finance and technology affordably. To attract outside resources, these firms must often use external commitments for repayment. Research suggests that a common commitment mechanism is to borrow US securities laws, which involves listing the emerging economy firm's shares on a US exchange. This paper uses a quasi-natural experiment from M...

  1. Investigation of the mechanisms of neuroprotection mediated by Ro5-4864 in brain injury.

    Science.gov (United States)

    Palzur, Eilam; Sharon, Aviram; Shehadeh, Mona; Soustiel, Jean Francois

    2016-08-01

    Increasing evidence has established the involvement of the 18-kDa translocator protein (TSPO) in the process of mitochondrial membrane permeabilization and subsequent apoptosis through modulation of the mitochondrial permeability transition pore. Recent studies have shown that treatment with Ro5-4864, a TSPO ligand, resulted in a neuroprotective effect in traumatic brain injury. Yet, the nature of this effect remained uncertain as mature neurons are considered to be lacking the TSPO protein. In order to investigate the mechanism of Ro5-4864-mediated neuroprotection, the neuro-inflammatory and neurosteroid response to cortical injury was tested in sham-operated, vehicle, cyclosporine A (CsA) and Ro5-4864-treated rats. As anticipated, the levels of interleukin 1β and tumor necrosis factor α, as well as the astrocyte and microglia cellular density in the injured area were all decreased by CsA in comparison with the vehicle group. By contrast, no visible effect could be observed in Ro5-4864-treated animals. None of the groups showed any significant difference with any other in respect with the expression of brain-derived neurotrophic factor. Double immunofluorescence staining with NeuN and TSPO confirmed the absence of TSPO in native neurons though showed clear evidence of co-localization of TSPO in the cytoplasm of NeuN-stained injured neurons. Altogether, this study shows that the neuronal protection mediated by Ro5-4864 in brain injury cannot be solely attributed to an indirect effect of the ligand on glial TSPO but may also represent the consequence of the modulation of upregulated TSPO in injured neurons. This observation may be of importance for future pharmacological research in neurotrauma. PMID:27223627

  2. 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.

  3. Social Robots, Brain Machine Interfaces and Neuro/Cognitive Enhancers: Three Emerging Science and Technology Products through the Lens of Technology Acceptance Theories, Models and Frameworks

    OpenAIRE

    Wolbring, Gregor; Diep, Lucy; Yumakulov, Sophya; Ball, Natalie; Yergens, Dean

    2013-01-01

    Social robotics, brain machine interfaces and neuro and cognitive enhancement products are three emerging science and technology products with wide-reaching impact for disabled and non-disabled people. Acceptance of ideas and products depend on multiple parameters and many models have been developed to predict product acceptance. We investigated which frequently employed technology acceptance models (consumer theory, innovation diffusion model, theory of reasoned action, theory of planned beh...

  4. Oscillatory brain activity related to control mechanisms during laboratory-induced reactive aggression

    Directory of Open Access Journals (Sweden)

    Ulrike M Krämer

    2009-11-01

    Full Text Available Aggressive behavior is a common reaction in humans after an interpersonal provocation, but little is known about the underlying brain mechanisms. The present study analyzed oscillatory brain activity while participants were involved in an aggressive interaction to examine the neural processes subserving the associated decision and evaluation processes. Participants were selected from a larger sample because of their high scores in trait aggressiveness. We used a competitive reaction time task that induces aggressive behavior through provocation. Each trial is separated in a decision phase, during which the punishment for the opponent is set, and an outcome phase, during which the actual punishment is applied or received. We observed provocation-related differences during the decision phase in the theta band which differed depending on participants’ aggressive behavior: High provocation was associated with an increased frontal theta response in participants refraining from retaliation, but with reduced theta power in those who got back to the opponent. Moreover, more aggressive decisions after being punished were associated with a decrease of frontal theta power. Non-aggressive and aggressive participants differed also in their outcome-related response: Being punished led to an increased frontal theta power compared to win trials in the latter only, pointing to differences in evaluation processes associated with their different behavioral reactions. The data thus support previous evidence for a role of prefrontal areas in the control of reactive aggression and extend behavioral studies on associations between aggression or violence and impaired prefrontal functions.

  5. Impairment of interrelated iron- and copper homeostatic mechanisms in brain contributes to the pathogenesis of neurodegenerative disorders

    Directory of Open Access Journals (Sweden)

    Tina eSkjørringe

    2012-09-01

    Full Text Available Iron and copper are important co-factors for a number of enzymes in the brain, including enzymes involved in neurotransmitter synthesis and myelin formation. Both shortage and an excess of iron or copper will affect the brain. The transport of iron and copper into the brain from the circulation is strictly regulated, and concordantly protective barriers i.e. the blood-brain barrier (BBB and the blood-cerebrospinal fluid (CSF barrier (BCB have evolved to separate the brain environment from the circulation. The uptake mechanisms of the two metals interact. Both iron deficiency and overload lead to altered copper homeostasis in the brain. Similarly, changes in dietary copper affect the brain-iron homeostasis. Moreover, the uptake routes of iron and copper overlap each other which affect the interplay between the concentrations of the two metals in the brain. The divalent metal transporter-1 (DMT1 is involved in the uptake of both iron and copper. Furthermore, copper is an essential co-factor in numerous proteins that are vital for iron homeostasis and affects the binding of iron-response proteins to iron-response elements in the mRNA of the transferrin receptor, DMT1 and ferroportin, all highly involved in iron transport. Iron and copper are mainly taken up at the BBB, but the BCB also plays a vital role in the homeostasis of the two metals, in terms of sequestering, uptake and efflux of iron and copper from the brain. Inside the brain, iron and copper are taken up by neurons and glia cells that express various transporters

  6. State and Training Effects of Mindfulness Meditation on Brain Networks Reflect Neuronal Mechanisms of Its Antidepressant Effect

    OpenAIRE

    Chuan-Chih Yang; Alfonso Barrós-Loscertales; Daniel Pinazo; Noelia Ventura-Campos; Viola Borchardt; Juan-Carlos Bustamante; Aina Rodríguez-Pujadas; Paola Fuentes-Claramonte; Raúl Balaguer; César Ávila; Martin Walter

    2016-01-01

    The topic of investigating how mindfulness meditation training can have antidepressant effects via plastic changes in both resting state and meditation state brain activity is important in the rapidly emerging field of neuroplasticity. In the present study, we used a longitudinal design investigating resting state fMRI both before and after 40 days of meditation training in 13 novices. After training, we compared differences in network connectivity between rest and meditation using common res...

  7. A mechanism for proven technology foresight for emerging fast reactor designs and concepts

    Science.gov (United States)

    Anuar, Nuraslinda; Muhamad Pauzi, Anas

    2016-01-01

    The assessment of emerging nuclear fast reactor designs and concepts viability requires a combination of foresight methods. A mechanism that allows for the comparison and quantification of the possibility of being a proven technology in the future, β for the existing fast reactor designs and concepts is proposed as one of the quantitative foresight method. The methodology starts with the identification at the national or regional level, of the factors that would affect β. The factors are then categorized into several groups; economic, social and technology elements. Each of the elements is proposed to be mathematically modelled before all of the elemental models can be combined. Once the overall β model is obtained, the βmin is determined to benchmark the acceptance as a candidate design or concept. The β values for all the available designs and concepts are then determined and compared with the βmin, resulting in a list of candidate designs that possess the β value that is larger than the βmin. The proposed methodology can also be applied to purposes other than technological foresight.

  8. A mechanism for proven technology foresight for emerging fast reactor designs and concepts

    Energy Technology Data Exchange (ETDEWEB)

    Anuar, Nuraslinda, E-mail: nuraslinda@uniten.edu.my; Muhamad Pauzi, Anas, E-mail: anas@uniten.edu.my [College of Engineering, Universiti Tenaga Nasional, Jalan IKRAM-UNITEN, 43000 Kajang, Selangor (Malaysia)

    2016-01-22

    The assessment of emerging nuclear fast reactor designs and concepts viability requires a combination of foresight methods. A mechanism that allows for the comparison and quantification of the possibility of being a proven technology in the future, β for the existing fast reactor designs and concepts is proposed as one of the quantitative foresight method. The methodology starts with the identification at the national or regional level, of the factors that would affect β. The factors are then categorized into several groups; economic, social and technology elements. Each of the elements is proposed to be mathematically modelled before all of the elemental models can be combined. Once the overall β model is obtained, the β{sub min} is determined to benchmark the acceptance as a candidate design or concept. The β values for all the available designs and concepts are then determined and compared with the β{sub min}, resulting in a list of candidate designs that possess the β value that is larger than the β{sub min}. The proposed methodology can also be applied to purposes other than technological foresight.

  9. 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.

  10. The biological significance of brain barrier mechanisms: help or hindrance in drug delivery to the central nervous system?

    Science.gov (United States)

    Saunders, Norman R; Habgood, Mark D; Møllgård, Kjeld; Dziegielewska, Katarzyna M

    2016-01-01

    Barrier mechanisms in the brain are important for its normal functioning and development. Stability of the brain's internal environment, particularly with respect to its ionic composition, is a prerequisite for the fundamental basis of its function, namely transmission of nerve impulses. In addition, the appropriate and controlled supply of a wide range of nutrients such as glucose, amino acids, monocarboxylates, and vitamins is also essential for normal development and function. These are all cellular functions across the interfaces that separate the brain from the rest of the internal environment of the body. An essential morphological component of all but one of the barriers is the presence of specialized intercellular tight junctions between the cells comprising the interface: endothelial cells in the blood-brain barrier itself, cells of the arachnoid membrane, choroid plexus epithelial cells, and tanycytes (specialized glial cells) in the circumventricular organs. In the ependyma lining the cerebral ventricles in the adult brain, the cells are joined by gap junctions, which are not restrictive for intercellular movement of molecules. But in the developing brain, the forerunners of these cells form the neuroepithelium, which restricts exchange of all but the smallest molecules between cerebrospinal fluid and brain interstitial fluid because of the presence of strap junctions between the cells. The intercellular junctions in all these interfaces are the physical basis for their barrier properties. In the blood-brain barrier proper, this is combined with a paucity of vesicular transport that is a characteristic of other vascular beds. Without such a diffusional restrain, the cellular transport mechanisms in the barrier interfaces would be ineffective. Superimposed on these physical structures are physiological mechanisms as the cells of the interfaces contain various metabolic transporters and efflux pumps, often ATP-binding cassette (ABC) transporters, that

  11. Reward mechanisms in the brain and their role in dependence : evidence from neurophysiological and neuroimaging studies

    NARCIS (Netherlands)

    Martin-Soelch, C; Leenders, KL; Chevalley, AF; Missimer, J; Kunig, G; Magyar, S; Mino, A; Schultz, W

    2001-01-01

    This article reviews neuronal activity related to reward processing in primate and human brains. In the primate brain, neurophysiological methods provide a differentiated view of reward processing in a limited number of brain structures. Dopamine neurons respond to unpredictable rewards and produce

  12. Nurses' perceptions of using an evidence-based care bundle for initial emergency nursing management of patients with severe traumatic brain injury: A qualitative study.

    Science.gov (United States)

    Damkliang, Jintana; Considine, Julie; Kent, Bridie; Street, Maryann

    2015-10-01

    Evidence to guide initial emergency nursing care of patients with severe traumatic brain injury (TBI) in Thailand is currently not available in a useable form. A care bundle was used to summarise an evidence-based approach to the initial emergency nursing management of patients with severe TBI and was implemented in one Thai emergency department. The aim of this study was to describe Thai emergency nurses' perceptions of care bundle use. A descriptive qualitative study was used to describe emergency nurses' perceptions of care bundle use during the implementation phase (Phase-One) and then post-implementation (Phase-Two). Ten emergency nurses participated in Phase-One, while 12 nurses participated in Phase-Two. In Phase-One, there were five important factors identified in relation to use of the care bundle including quality of care, competing priorities, inadequate equipment, agitated patients, and teamwork. In Phase Two, participants perceived that using the care bundle helped them to improve quality of care, increased nurses' knowledge, skills, and confidence. Care bundles are one strategy to increase integration of research evidence into clinical practice and facilitate healthcare providers to deliver optimal patient care in busy environments with limited resources. PMID:26049810

  13. Hyperphosphorylation and accumulation of neurofilament proteins in Alzheimer brain and the possible mechanism

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Alzheimer disease (AD) neurofibrillary degeneration is characterized by a disruption of the cytoskeleton. The alteration of microtubule system and the microtubule-associated protein has been extensively investigated in this pathology. In the present study, we decided to explore the role of neurofilament (NF) proteins in AD neurofibrillary degeneration. We first investigated the content and the phosphorylation level of NF proteins in AD brain by using a panel of anti-NF antibodies. It was found by quantitative Western blot that the NF subunits were exclusively detected in an insoluble fraction from AD brain grey matter. The level of phosphorylated (p)-NF-H and (p)-NF-M was increased 1.5 and 1.3 times (P<0.05) respectively at phosphorylation specific antibody SMI31 epitope in AD as compared to neurological controls of Huntington disease (HD). A 1.6 fold elevation (P>0.05) of p-NF-H to another phosphate reactive antibody SMI34 was also seen in AD. The level of non-phosphorylated (np)-NF-H/M recognized by SMI33 was similar before alkaline phosphatase (ALP) treatment, but the total level of NF-H/M was 1.5 and 1.6 times (P<0.01) higher in AD than HD after dephosphorylation. Furthermore, a 1.8 fold increase of NF-M to SMI32 was observed in AD only after ALP treatment, suggesting that the NF-H/M are increased in the phosphorylated form. The amount of NF-L determined by NR-4 was 1.6 fold (P<0.01) higher in AD than HD. To our knowledge, this is the first biochemical data shown definite abnormality of NF subunits in AD brain. To understand the possible mechanism for the abnormal hyperphosphorylation and elevation of NF in AD brain, we treated human SY5Y neuroblastoma cell with protein phosphatase(PP)-2A and PP-1 inhibitor okadaic acid(OA). Then, we determined the relationship between an AD-like PP-A and PP-1 activity deficiency and NF phosphorylation as well as intracellular translocation in modeled cell system. It was demonstrated that p-NF-H/M detected by SMI31 and

  14. Microcavitation as a Neuronal Damage Mechanism in Blast Traumatic Brain Injury

    Science.gov (United States)

    Franck, Christian; Estrada, Jonathan

    2015-11-01

    Blast traumatic brain injury (bTBI) is a leading cause of injury in the armed forces. Diffuse axonal injury, the hallmark feature of blunt TBI, has been investigated in direct mechanical loading conditions. However, recent evidence suggests inertial cavitation as a possible bTBI mechanism, particularly in the case of exposure to blasts. Cavitation damage to free surfaces has been well-studied, but bubble interactions within confined 3D environments, in particular their stress and strain signatures are not well understood. The structural damage due to cavitation in living tissues - particularly at the cellular level - are incompletely understood, in part due to the rapid bubble formation and deformation strain rates of up to ~ 105-106 s-1. This project aims to characterize material damage in 2D and 3D cell culture environments by utilizing a novel high-speed red-blue diffraction assisted image correlation method at speeds of up to 106 frames per second. We gratefully acknowledge funding from the Office of Naval Research (POC: Dr. Tim Bentley).

  15. Molecular Electrical Doping of Organic Semiconductors: Fundamental Mechanisms and Emerging Dopant Design Rules.

    Science.gov (United States)

    Salzmann, Ingo; Heimel, Georg; Oehzelt, Martin; Winkler, Stefanie; Koch, Norbert

    2016-03-15

    Today's information society depends on our ability to controllably dope inorganic semiconductors, such as silicon, thereby tuning their electrical properties to application-specific demands. For optoelectronic devices, organic semiconductors, that is, conjugated polymers and molecules, have emerged as superior alternative owing to the ease of tuning their optical gap through chemical variability and their potential for low-cost, large-area processing on flexible substrates. There, the potential of molecular electrical doping for improving the performance of, for example, organic light-emitting devices or organic solar cells has only recently been established. The doping efficiency, however, remains conspicuously low, highlighting the fact that the underlying mechanisms of molecular doping in organic semiconductors are only little understood compared with their inorganic counterparts. Here, we review the broad range of phenomena observed upon molecularly doping organic semiconductors and identify two distinctly different scenarios: the pairwise formation of both organic semiconductor and dopant ions on one hand and the emergence of ground state charge transfer complexes between organic semiconductor and dopant through supramolecular hybridization of their respective frontier molecular orbitals on the other hand. Evidence for the occurrence of these two scenarios is subsequently discussed on the basis of the characteristic and strikingly different signatures of the individual species involved in the respective doping processes in a variety of spectroscopic techniques. The critical importance of a statistical view of doping, rather than a bimolecular picture, is then highlighted by employing numerical simulations, which reveal one of the main differences between inorganic and organic semiconductors to be their respective density of electronic states and the doping induced changes thereof. Engineering the density of states of doped organic semiconductors, the Fermi

  16. Heparanase mediates a novel mechanism in lapatinib-resistant brain metastatic breast cancer

    Directory of Open Access Journals (Sweden)

    Lixin Zhang

    2015-01-01

    Full Text Available Heparanase (HPSE is the dominant mammalian endoglycosidase and important tumorigenic, angiogenic, and pro-metastatic molecule. Highest levels of HPSE activity have been consistently detected in cells possessing highest propensities to colonize the brain, emphasizing the therapeutic potential for targeting HPSE in brain metastatic breast cancer (BMBC. Lapatinib (Tykerb is a small-molecule and dual inhibitor of human epidermal growth factor receptor1 and 2 (EGFR and HER2, respectively which are both high-risk predictors of BMBC. It was approved by the US Food and Drug Administration for treatment of patients with advanced or metastatic breast cancer. However, its role is limited in BMBC whose response rates to lapatinib are significantly lower than those for extracranial metastasis. Because HPSE can affect EGFR phosphorylation, we examined Roneparstat, a non-anticoagulant heparin with potent anti-HPSE activity, to inhibit EGFR signaling pathways and BMBC onset using lapatinib-resistant clones generated from HER2-transfected, EGFR-expressing MDA-MB-231BR cells. Cell growth, EGFR pathways, and HPSE targets were assessed among selected clones in the absence or presence of Roneparstat and/or lapatinib. Roneparstat overcame lapatinib resistance by inhibiting pathways associated with EGFR tyrosine residues that are not targeted by lapatinib. Roneparstat inhibited the growth and BMBC abilities of lapatinib-resistant clones. A molecular mechanism was identified by which HPSE mediates an alternative survival pathway in lapatinib-resistant clones and is modulated by Roneparstat. These results demonstrate that the inhibition of HPSE-mediated signaling plays important roles in lapatinib resistance, and provide mechanistic insights to validate the use of Roneparstat for novel BMBC therapeutic strategies.

  17. BRAIN PLASTICITY: MUSICAL TRAINING INVOLVEMENT

    OpenAIRE

    Verónika Diaz Abrahan; Nadia Justel

    2012-01-01

    The main research about the effect of musical training in adult and childhood brain was revised in this work. The music realizes unique demands to our ner-vous system. This call the attention of several researchers causing, in the past years, an enhancement of the exploration about this topic; this increment was benefit for the emergence of new neuroimaging techniques, the music positioned as an investigation tool of human cognition and superior brain mechanisms. The musical perception and pr...

  18. The emergence of age-dependent social cognitive deficits after generalized insult to the developing brain: a longitudinal prospective analysis using susceptibility-weighted imaging.

    Science.gov (United States)

    Ryan, Nicholas P; Catroppa, Cathy; Cooper, Janine M; Beare, Richard; Ditchfield, Michael; Coleman, Lee; Silk, Timothy; Crossley, Louise; Beauchamp, Miriam H; Anderson, Vicki A

    2015-05-01

    Childhood and adolescence are critical periods for maturation of neurobiological processes that underlie complex social and emotional behavior including Theory of Mind (ToM). While structural correlates of ToM are well described in adults, less is known about the anatomical regions subsuming these skills in the developing brain or the impact of cerebral insult on the acquisition and establishment of high-level social cognitive skills. This study aimed to examine the differential influence of age-at-insult and brain pathology on ToM in a sample of children and adolescents with traumatic brain injury (TBI). Children and adolescents with TBI (n = 112) were categorized according to timing of brain insult: (i) middle childhood (5-9 years; n = 41); (ii) late childhood (10-11 years; n = 39); and (iii) adolescence (12-15 years; n = 32) and group-matched for age, gender, and socioeconomic status to a typically developing (TD) control group (n = 43). Participants underwent magnetic resonance imaging including a susceptibility-weighted imaging (SWI) sequence 2-8 weeks postinjury and were assessed on a battery of ToM tasks at 6- and 24-months after injury. Results showed that for adolescents with TBI, social cognitive dysfunction at 6- and 24-months postinjury was associated with diffuse neuropathology and a greater number of lesions detected using SWI. In the late childhood TBI group, we found a time-dependent emergence of social cognitive impairment, linked to diffuse neuropathology. The middle childhood TBI group demonstrated performance unrelated to SWI pathology and comparable to TD controls. Findings indicate that the full extent of social cognitive deficits may not be realized until the associated skills reach maturity. Evidence for brain structure-function relationships suggests that the integrity of an anatomically distributed network of brain regions and their connections is necessary for the acquisition and establishment of high-level social

  19. The 13th J. A. F. Stevenson memorial lecture. Sexual differentiation of the brain: possible mechanisms and implications.

    Science.gov (United States)

    Gorski, R A

    1985-06-01

    The mammalian brain appears to be inherently feminine and the action of testicular hormones during development is necessary for the differentiation of the masculine brain both in terms of functional potential and actual structure. Experimental evidence for this statement is reviewed in this discussion. Recent discoveries of marked structural sex differences in the central nervous system, such as the sexually dimorphic nucleus of the preoptic area in the rat, offer model systems to investigate potential mechanisms by which gonadal hormones permanently modify neuronal differentiation. Although effects of these steroids on neurogenesis and neuronal migration and specification have not been conclusively eliminated, it is currently believed, but not proven, that the principle mechanism of steroid action is to maintain neuronal survival during a period of neuronal death. The structural models of the sexual differentiation of the central nervous system also provide the opportunity to identify sex differences in neurochemical distribution. Two examples in the rat brain are presented: the distribution of serotonin-immunoreactive fibers in the medial preoptic nucleus and of tyrosine hydroxylase-immunoreactive fibers and cells in the anteroventral periventricular nucleus. It is likely that sexual dimorphisms will be found to be characteristic of many neural and neurochemical systems. The final section of this review raises the possibility that the brain of the adult may, in response to steroid action, be morphologically plastic, and considers briefly the likelihood that the brain of the human species is also influenced during development by the hormonal environment.

  20. PREFACE: DICE 2012 : Spacetime Matter Quantum Mechanics - from the Planck scale to emergent phenomena

    Science.gov (United States)

    Diósi, Lajos; Elze, Hans-Thomas; Fronzoni, Leone; Halliwell, Jonathan; Prati, Enrico; Vitiello, Giuseppe; Yearsley, James

    2013-06-01

    Presented in this volume are the Invited Lectures and the Contributed Papers of the Sixth International Workshop on Decoherence, Information, Complexity and Entropy - DICE 2012, held at Castello Pasquini, Castiglioncello (Tuscany), 17-21 September 2012. These proceedings may document to the interested public and to the wider scientific community the stimulating exchange of ideas at the meeting. The number of participants has been steadily growing over the years, reflecting an increasing attraction, if not need, of such conference. Our very intention has always been to bring together leading researchers, advanced students, and renowned scholars from various areas, in order to stimulate new ideas and their exchange across the borders of specialization. In this way, the series of meetings successfully continued from the beginning with DICE 20021, followed by DICE 20042, DICE 20063, DICE 20084, and DICE 20105, Most recently, DICE 2012 brought together more than 120 participants representing more than 30 countries worldwide. It has been a great honour and inspiration to have Professor Yakir Aharonov (Tel Aviv) with us, who presented the opening Keynote Lecture 'The two-vector quantum formalism'. With the overarching theme 'Spacetime - Matter - Quantum Mechanics - from the Planck scale to emergent phenomena', the conference took place in the very pleasant and inspiring atmosphere of Castello Pasquini - in beautiful surroundings, overlooking a piece of Tuscany's coast. The 5-day program covered these major topics: Quantum Mechanics, Foundations and Quantum-Classical Border Quantum-Classical Hybrids and Many-Body Systems Spectral Geometry, Path Integrals and Experiments Quantum -/- Gravity -/- Spacetime Quantum Mechanics on all Scales? A Roundtable Discussion under the theme 'Nuovi orizzonti nella ricerca scientifica. Ci troviamo di fronte ad una rivoluzione scientifica?' formed an integral part of the program. With participation of E Del Giudice (INFN & Università di

  1. Social Robots, Brain Machine Interfaces and Neuro/Cognitive Enhancers: Three Emerging Science and Technology Products through the Lens of Technology Acceptance Theories, Models and Frameworks

    Directory of Open Access Journals (Sweden)

    Gregor Wolbring

    2013-06-01

    Full Text Available Social robotics, brain machine interfaces and neuro and cognitive enhancement products are three emerging science and technology products with wide-reaching impact for disabled and non-disabled people. Acceptance of ideas and products depend on multiple parameters and many models have been developed to predict product acceptance. We investigated which frequently employed technology acceptance models (consumer theory, innovation diffusion model, theory of reasoned action, theory of planned behaviour, social cognitive theory, self-determination theory, technology of acceptance model, Unified Theory of Acceptance and Use of Technology UTAUT and UTAUT2 are employed in the social robotics, brain machine interfaces and neuro and cognitive enhancement product literature and which of the core measures used in the technology acceptance models are implicit or explicit engaged with in the literature.

  2. Emotion recognition and emergent leadership : Unraveling mediating mechanisms and boundary conditions

    NARCIS (Netherlands)

    Walter, F.; Cole, M.S.; van der Vegt, G.S.; Rubin, R.S.; Bommer, W.H.

    2012-01-01

    This study examines the complex connection between individuals' emotion recognition capability and their emergence as leaders. It is hypothesized that emotion recognition and extraversion interactively relate with an individual's task coordination behavior which, in turn, influences the likelihood o

  3. Selective sensation based brain-computer interface via mechanical vibrotactile stimulation.

    Directory of Open Access Journals (Sweden)

    Lin Yao

    Full Text Available In this work, mechanical vibrotactile stimulation was applied to subjects' left and right wrist skins with equal intensity, and a selective sensation perception task was performed to achieve two types of selections similar to motor imagery Brain-Computer Interface. The proposed system was based on event-related desynchronization/synchronization (ERD/ERS, which had a correlation with processing of afferent inflow in human somatosensory system, and attentional effect which modulated the ERD/ERS. The experiments were carried out on nine subjects (without experience in selective sensation, and six of them showed a discrimination accuracy above 80%, three of them above 95%. Comparative experiments with motor imagery (with and without presence of stimulation were also carried out, which further showed the feasibility of selective sensation as an alternative BCI task complementary to motor imagery. Specifically there was significant improvement ([Formula: see text] from near 65% in motor imagery (with and without presence of stimulation to above 80% in selective sensation on some subjects. The proposed BCI modality might well cooperate with existing BCI modalities in the literature in enlarging the widespread usage of BCI system.

  4. The role of different cues in the brain mechanism on visual spatial attention

    Institute of Scientific and Technical Information of China (English)

    SONG Weiqun; LUO Yuejia; CHI Song; JI Xunming; LING Feng; ZHAO Lun; WANG Maobin; SHI Jiannong

    2006-01-01

    The visual spatial attention mechanism in the brain was studied in 16 young subjects through the visual search paradigm of precue-target by the event-related potential (ERP) technique, with the attentive ranges cued by different scales of Chinese character and region cues. The results showed that the response time for Chinese character cues was much longer than that for region cues especially for small region cues. With the exterior interferences, the target stimuli recognition under region cues was much quicker than that under Chinese character cues. Compared with that under region cues, targets under Chinese character cues could lead to increase of the posterior P1,decrease of the N1 and increase of the P2. It should also be noted that the differences between region cues and Chinese character cues were affected by the interference types. Under exterior interferences, no significant difference was found between region cues and Chinese character cues; however, it was not the case under the interior interferences. Considering the difference between the exterior interferences and the interior interferences, we could conclude that with the increase of difficulty in target recognition there was obvious difference in the consumption of anterior frontal resources by target stimuli under the two kinds of cues.

  5. Brain-Derived Neurotrophic Factor in Alzheimer's Disease: Risk, Mechanisms, and Therapy.

    Science.gov (United States)

    Song, Jing-Hui; Yu, Jin-Tai; Tan, Lan

    2015-12-01

    Brain-derived neurotrophic factor (BDNF) has a neurotrophic support on neuron of central nervous system (CNS) and is a key molecule in the maintenance of synaptic plasticity and memory storage in hippocampus. However, changes of BDNF level and expression have been reported in the CNS as well as blood of Alzheimer's disease (AD) patients in the last decade, which indicates a potential role of BDNF in the pathogenesis of AD. Therefore, this review aims to summarize the latest progress in the field of BDNF and its biological roles in AD pathogenesis. We will discuss the interaction between BDNF and amyloid beta (Aβ) peptide, the effect of BDNF on synaptic repair in AD, and the association between BDNF polymorphism and AD risk. The most important is, enlightening the detailed biological ability and complicated mechanisms of action of BDNF in the context of AD would provide a future BDNF-related remedy for AD, such as increment in the production or release of endogenous BDNF by some drugs or BDNF mimics.

  6. Investigation of cavitation as a possible damage mechanism in blast-induced traumatic brain injury.

    Science.gov (United States)

    Goeller, Jacques; Wardlaw, Andrew; Treichler, Derrick; O'Bruba, Joseph; Weiss, Greg

    2012-07-01

    Cavitation was investigated as a possible damage mechanism for war-related traumatic brain injury (TBI) due to an improvised explosive device (IED) blast. When a frontal blast wave encounters the head, a shock wave is transmitted through the skull, cerebrospinal fluid (CSF), and tissue, causing negative pressure at the contrecoup that may result in cavitation. Numerical simulations and shock tube experiments were conducted to determine the possibility of cranial cavitation from realistic IED non-impact blast loading. Simplified surrogate models of the head consisted of a transparent polycarbonate ellipsoid. The first series of tests in the 18-inch-diameter shock tube were conducted on an ellipsoid filled with degassed water to simulate CSF and tissue. In the second series, Sylgard gel, surrounded by a layer of degassed water, was used to represent the tissue and CSF, respectively. Simulated blast overpressure in the shock tube tests ranged from a nominal 10-25 pounds per square inch gauge (psig; 69-170 kPa). Pressure in the simulated CSF was determined by Kulite thin line pressure sensors at the coup, center, and contrecoup positions. Using video taken at 10,000 frames/sec, we verified the presence of cavitation bubbles at the contrecoup in both ellipsoid models. In all tests, cavitation at the contrecoup was observed to coincide temporally with periods of negative pressure. Collapse of the cavitation bubbles caused by the surrounding pressure and elastic rebound of the skull resulted in significant pressure spikes in the simulated CSF. Numerical simulations using the DYSMAS hydrocode to predict onset of cavitation and pressure spikes during cavity collapse were in good agreement with the tests. The numerical simulations and experiments indicate that skull deformation is a significant factor causing cavitation. These results suggest that cavitation may be a damage mechanism contributing to TBI that requires future study.

  7. On the emergence of quantum mechanics, diffeomorphism invariance and the weak equivalence principle from deterministic Cartan-Randers systems

    CERN Document Server

    Torromé, Ricardo Gallego

    2014-01-01

    In this work, deterministic Cartan-Randers dynamical systems, a particular class of {\\it deterministic quantum models} associated to first order ordinary differential equations are considered. Then we show that {\\it diffeomorphism invariance}, a classical and a quantum versions of a Principle of Inertia, reversibility of the effective quantum dynamics and a {\\it covariant maximal universal acceleration} emerge from deterministic Cartan-Randers models. A geometric analytic mechanism for quantum measurement processes without reduction of wave packet appears naturally. The mechanism is applied heuristically to the quantum two slit experiment. The mechanism allows for protective measurement and usual Von Neumann measurements. Furthermore, a similar geometric-analytic mechanism is discovered to produce a lower bound for physical values for the eigenvalues of Hamiltonian for matter. As a side effect of such mechanism, a natural explanation for the Weak Equivalence Principle is obtained. This fact together with the ...

  8. An anisotropic hyperelastic constitutive model of brain white matter in biaxial tension and structural-mechanical relationships.

    Science.gov (United States)

    Labus, Kevin M; Puttlitz, Christian M

    2016-09-01

    Computational models of the brain require accurate and robust constitutive models to characterize the mechanical behavior of brain tissue. The anisotropy of white matter has been previously demonstrated; however, there is a lack of data describing the effects of multi-axial loading, even though brain tissue experiences multi-axial stress states. Therefore, a biaxial tensile experiment was designed to more fully characterize the anisotropic behavior of white matter in a quasi-static loading state, and the mechanical data were modeled with an anisotropic hyperelastic continuum model. A probabilistic analysis was used to quantify the uncertainty in model predictions because the mechanical data of brain tissue can show a high degree of variability, and computational studies can benefit from reporting the probability distribution of model responses. The axonal structure in white matter can be heterogeneous and regionally dependent, which can affect computational model predictions. Therefore, corona radiata and corpus callosum regions were tested, and histology and transmission electron microscopy were performed on tested specimens to relate the distribution of axon orientations and the axon volume fraction to the mechanical behavior. These measured properties were implemented into a structural constitutive model. Results demonstrated a significant, but relatively low anisotropic behavior, yet there were no conclusive mechanical differences between the two regions tested. The inclusion of both biaxial and uniaxial tests in model fits improved the accuracy of model predictions. The mechanical anisotropy of individual specimens positively correlated with the measured axon volume fraction, and, accordingly, the structural model exhibited slightly decreased uncertainty in model predictions compared to the model without structural properties. PMID:27214689

  9. An anisotropic hyperelastic constitutive model of brain white matter in biaxial tension and structural-mechanical relationships.

    Science.gov (United States)

    Labus, Kevin M; Puttlitz, Christian M

    2016-09-01

    Computational models of the brain require accurate and robust constitutive models to characterize the mechanical behavior of brain tissue. The anisotropy of white matter has been previously demonstrated; however, there is a lack of data describing the effects of multi-axial loading, even though brain tissue experiences multi-axial stress states. Therefore, a biaxial tensile experiment was designed to more fully characterize the anisotropic behavior of white matter in a quasi-static loading state, and the mechanical data were modeled with an anisotropic hyperelastic continuum model. A probabilistic analysis was used to quantify the uncertainty in model predictions because the mechanical data of brain tissue can show a high degree of variability, and computational studies can benefit from reporting the probability distribution of model responses. The axonal structure in white matter can be heterogeneous and regionally dependent, which can affect computational model predictions. Therefore, corona radiata and corpus callosum regions were tested, and histology and transmission electron microscopy were performed on tested specimens to relate the distribution of axon orientations and the axon volume fraction to the mechanical behavior. These measured properties were implemented into a structural constitutive model. Results demonstrated a significant, but relatively low anisotropic behavior, yet there were no conclusive mechanical differences between the two regions tested. The inclusion of both biaxial and uniaxial tests in model fits improved the accuracy of model predictions. The mechanical anisotropy of individual specimens positively correlated with the measured axon volume fraction, and, accordingly, the structural model exhibited slightly decreased uncertainty in model predictions compared to the model without structural properties.

  10. Invasive Mechanical Ventilation in California Over 2000-2009: Implications for Emergency Medicine

    Directory of Open Access Journals (Sweden)

    Seshadri C. Mudumbai

    2015-10-01

    Full Text Available Introduction: Patients who require invasive mechanical ventilation (IMV often represent a sequence of care between the emergency department (ED and intensive care unit (ICU. Despite being the most populous state, little information exists to define patterns of IMV use within the state of California. Methods: We examined data from the masked Patient Discharge Database of California’s Office of Statewide Health Planning and Development from 2000-2009. Adult patients who received IMV during their stay were identified using the International Classification of Diseases 9th Revision and Clinical Modification procedure codes (96.70, 96.71, 96.72. Patients were divided into age strata (18-34yr, 35-64yr, and >65yr. Using descriptive statistics and regression analyses, for IMV discharges during the study period, we quantified the number of ED vs. non-ED based admissions; changes in patient characteristics and clinical outcome; evaluated the marginal costs for IMV; determined predictors for prolonged acute mechanical ventilation (PAMV, i.e. IMV>96hr; and projected the number of IMV discharges and ED-based admissions by year 2020. Results: There were 696,634 IMV discharges available for analysis. From 2000–2009, IMV discharges increased by 2.8%/year: n=60,933 (293/100,000 persons in 2000 to n=79,868 (328/100,000 persons in 2009. While ED-based admissions grew by 3.8%/year, non-ED-based admissions remained stable (0%. During 2000-2009, fastest growth was noted for 1 the 35–64 year age strata; 2 Hispanics; 3 patients with non-Medicare public insurance; and 4 patients requiring PAMV. Average total patient cost-adjusted charges per hospital discharge increased by 29% from 2000 (from $42,528 to $60,215 in 2014 dollars along with increases in the number of patients discharged to home and skilled nursing facilities. Higher marginal costs were noted for younger patients (ages 18-34yr, non-whites, and publicly insured patients. Some of the strongest predictors

  11. Improved mitochondrial function in brain aging and Alzheimer disease - the new mechanism of action of the old metabolic enhancer piracetam

    Directory of Open Access Journals (Sweden)

    Kristina Leuner

    2010-09-01

    Full Text Available Piracetam, the prototype of the so-called nootropic drugs’ is used since many years in different countries to treat cognitive impairment in aging and dementia. Findings that piracetam enhances fluidity of brain mitochondrial membranes led to the hypothesis that piracetam might improve mitochondrial function, e.g. might enhance ATP synthesis. This assumption has recently been supported by a number of observations showing enhanced mitochondrial membrane potential (MMP, enhanced ATP production, and reduced sensitivity for apoptosis in a variety of cell and animal models for aging and Alzheimer disease (AD. As a specific consequence, substantial evidence for elevated neuronal plasticity as a specific effect of piracetam has emerged. Taken together, these new findings can explain many of the therapeutic effects of piracetam on cognition in aging and dementia as well as different situations of brain dysfunctions.

  12. Research Review: Cholinergic Mechanisms, Early Brain Development, and Risk for Schizophrenia

    Science.gov (United States)

    Ross, Randal G.; Stevens, Karen E.; Proctor, William R.; Leonard, Sherry; Kisley, Michael A.; Hunter, Sharon K.; Freedman, Robert; Adams, Catherine E.

    2010-01-01

    The onset of diagnostic symptomology for neuropsychiatric diseases is often the end result of a decades-long process of aberrant brain development. Identification of novel treatment strategies aimed at normalizing early brain development and preventing mental illness should be a major therapeutic goal. However, there are few models for how this…

  13. 突发事件中警察应急处置机制研究%Study on Emergency Response Mechanism of Police in Emergencies

    Institute of Scientific and Technical Information of China (English)

    吴同; 王精忠

    2012-01-01

    China is in the key stage of social transition now. Kinds of social contradictions are coming forth continuously. Emergen- cies caused by these will possibly make social order unstable. Emergency response mechanism is organic connections with several essen- tials formed on police emergencies. Police organs should take timely, scientific and flexible measures, get involved in good time and re- spond swiftly, carry out disposition antecedently, communicate with media and disclose the news and strengthen the cooperation with oth- er administrative sections observing the principle of emergency response, the principle of proportion, the principle of publicity.%我国目前正处于社会转型的关键时期,各类新的社会矛盾不断涌现,由此引发的突发事件给社会秩序带来不稳定因素。突发事件处置机制是围绕公安应急处置活动而形成的多种要素的有机联系系统,公安机关在遵循应急性原则、比例原则和公开原则的前提下,处置突发事件应做到实时、科学和灵活的决策,及时介入、快速反应,应急性措施、先行处置权的实施和媒体沟通与信息披露,加强与其他行政部门的合作。

  14. Mindfulness Predicting Physical and Psychological Health in Emerging Adulthood: Understanding Mechanisms of Mindfulness using a Mediation Model

    OpenAIRE

    Lisman Lundwall, Christie Lynn

    2011-01-01

    ABSTRACT OF THE DISSERTATIONMindfulness Predicting Physical and Psychological Health in Emerging Adulthood: Understanding Mechanisms of Mindfulness using a Mediation Modelby Christie Lynn LundwallDoctor of Philosophy, Graduate Program in PsychologyUniversity of California, Riverside, December 2011Dr. Ruth K. Chao, ChairpersonThis study tested a theory derived multiple step structural equation model of four potential mediators of the relation from mindfulness to emotional distress, physical he...

  15. Resuscitation therapy for traumatic brain injury-induced coma in rats: mechanisms of median nerve electrical stimulation

    Directory of Open Access Journals (Sweden)

    Zhen Feng

    2015-01-01

    Full Text Available In this study, rats were put into traumatic brain injury-induced coma and treated with median nerve electrical stimulation. We explored the wake-promoting effect, and possible mechanisms, of median nerve electrical stimulation. Electrical stimulation upregulated the expression levels of orexin-A and its receptor OX1R in the rat prefrontal cortex. Orexin-A expression gradually increased with increasing stimulation, while OX1R expression reached a peak at 12 hours and then decreased. In addition, after the OX1R antagonist, SB334867, was injected into the brain of rats after traumatic brain injury, fewer rats were restored to consciousness, and orexin-A and OXIR expression in the prefrontal cortex was downregulated. Our findings indicate that median nerve electrical stimulation induced an up-regulation of orexin-A and OX1R expression in the prefrontal cortex of traumatic brain injury-induced coma rats, which may be a potential mechanism involved in the wake-promoting effects of median nerve electrical stimulation.

  16. Resuscitation therapy for traumatic brain injury-induced coma in rats:mechanisms of median nerve electrical stimulation

    Institute of Scientific and Technical Information of China (English)

    Zhen Feng; Ying-jun Zhong; Liang Wang; Tian-qi Wei

    2015-01-01

    In this study, rats were put into traumatic brain injury-induced coma and treated with median nerve electrical stimulation. We explored the wake-promoting effect, and possible mechanisms, of median nerve electrical stimulation. Electrical stimulation upregulated the expression levels of orexin-A and its receptor OX1R in the rat prefrontal cortex. Orexin-A expression gradually in-creased with increasing stimulation, while OX1R expression reached a peak at 12 hours and then decreased. In addition, after the OX1R antagonist, SB334867, was injected into the brain of rats after traumatic brain injury, fewer rats were restored to consciousness, and orexin-A and OXIR expression in the prefrontal cortex was downregulated. Our ifndings indicate that median nerve electrical stimulation induced an up-regulation of orexin-A and OX1R expression in the pre-frontal cortex of traumatic brain injury-induced coma rats, which may be a potential mechanism involved in the wake-promoting effects of median nerve electrical stimulation.

  17. Proceedings of the Third Annual Deep Brain Stimulation Think Tank: A Review of Emerging Issues and Technologies

    OpenAIRE

    Rossi, P. Justin; Gunduz, Aysegul; Judy, Jack; Wilson, Linda; Machado, Andre; James J Giordano; Elias, W. Jeff; Rossi, Marvin A.; Butson, Christopher L.; Fox, Michael D.; McIntyre, Cameron C.; Pouratian, Nader; Swann, Nicole C.; de Hemptinne, Coralie; Gross, Robert E.

    2016-01-01

    The proceedings of the 3rd Annual Deep Brain Stimulation Think Tank summarize the most contemporary clinical, electrophysiological, imaging, and computational work on DBS for the treatment of neurological and neuropsychiatric disease. Significant innovations of the past year are emphasized. The Think Tank's contributors represent a unique multidisciplinary ensemble of expert neurologists, neurosurgeons, neuropsychologists, psychiatrists, scientists, engineers, and members of industry. Present...

  18. The Acute Inflammatory Response in Trauma/Hemorrhage and Traumatic Brain Injury : Current State and Emerging Prospects

    NARCIS (Netherlands)

    Namas, R.; Ghuma, A.; Hermus, L.; Zamora, R.; Okonkwo, D. O.; Billiar, T. R.; Vodovotz, Y.

    2009-01-01

    Traumatic injury/hemorrhagic shock (T/HS) elicits an acute inflammatory response that may result in death. Inflammation describes a coordinated series of molecular, cellular, tissue, organ, and systemic responses that drive the pathology of various diseases including T/HS and traumatic brain injury

  19. Chemical Genomics and Emerging DNA Technologies in the Identification of Drug Mechanisms and Drug Targets

    DEFF Research Database (Denmark)

    Olsen, Louise Cathrine Braun; Færgeman, Nils J.

    2012-01-01

    critical roles in the genomic age of biological research and drug discovery. In the present review we discuss how simple biological model organisms can be used as screening platforms in combination with emerging genomic technologies to advance the identification of potential drugs and their molecular...

  20. Speech and music shape the listening brain: evidence for shared domain-general mechanisms.

    Science.gov (United States)

    Asaridou, Salomi S; McQueen, James M

    2013-01-01

    Are there bi-directional influences between speech perception and music perception? An answer to this question is essential for understanding the extent to which the speech and music that we hear are processed by domain-general auditory processes and/or by distinct neural auditory mechanisms. This review summarizes a large body of behavioral and neuroscientific findings which suggest that the musical experience of trained musicians does modulate speech processing, and a sparser set of data, largely on pitch processing, which suggest in addition that linguistic experience, in particular learning a tone language, modulates music processing. Although research has focused mostly on music on speech effects, we argue that both directions of influence need to be studied, and conclude that the picture which thus emerges is one of mutual interaction across domains. In particular, it is not simply that experience with spoken language has some effects on music perception, and vice versa, but that because of shared domain-general subcortical and cortical networks, experiences in both domains influence behavior in both domains. PMID:23761776

  1. Speech and music shape the listening brain: evidence for shared domain-general mechanisms

    Directory of Open Access Journals (Sweden)

    Salomi S. Asaridou

    2013-06-01

    Full Text Available Are there bi-directional influences between speech perception and music perception? An answer to this question is essential for understanding the extent to which the speech and music that we hear are processed by domain-general auditory processes and/or by distinct neural auditory mechanisms. This review summarizes a large body of behavioral and neuroscientific findings which suggest that the musical experience of trained musicians does modulate speech processing, and a sparser set of data, largely on pitch processing, which suggest in addition that linguistic experience, in particular learning a tone language, modulates music processing. Although research has focused mostly on music on speech effects, we argue that both directions of influence need to be studied, and conclude that the picture which thus emerges is one of mutual interaction across domains. In particular, it is not simply that experience with spoken language has some effects on music perception, and vice versa, but that because of shared domain-general subcortical and cortical networks, experiences in both domains influence behavior in both domains.

  2. Towards a Pathway Inventory of the Human Brain for Modeling Disease Mechanisms Underlying Neurodegeneration.

    Science.gov (United States)

    Iyappan, Anandhi; Gündel, Michaela; Shahid, Mohammad; Wang, Jiali; Li, Hui; Mevissen, Heinz-Theodor; Müller, Bernd; Fluck, Juliane; Jirsa, Viktor; Domide, Lia; Younesi, Erfan; Hofmann-Apitius, Martin

    2016-04-12

    Molecular signaling pathways have been long used to demonstrate interactions among upstream causal molecules and downstream biological effects. They show the signal flow between cell compartments, the majority of which are represented as cartoons. These are often drawn manually by scanning through the literature, which is time-consuming, static, and non-interoperable. Moreover, these pathways are often devoid of context (condition and tissue) and biased toward certain disease conditions. Mining the scientific literature creates new possibilities to retrieve pathway information at higher contextual resolution and specificity. To address this challenge, we have created a pathway terminology system by combining signaling pathways and biological events to ensure a broad coverage of the entire pathway knowledge domain. This terminology was applied to mining biomedical papers and patents about neurodegenerative diseases with focus on Alzheimer's disease. We demonstrate the power of our approach by mapping literature-derived signaling pathways onto their corresponding anatomical regions in the human brain under healthy and Alzheimer's disease states. We demonstrate how this knowledge resource can be used to identify a putative mechanism explaining the mode-of-action of the approved drug Rasagiline, and show how this resource can be used for fingerprinting patents to support the discovery of pathway knowledge for Alzheimer's disease. Finally, we propose that based on next-generation cause-and-effect pathway models, a dedicated inventory of computer-processable pathway models specific to neurodegenerative diseases can be established, which hopefully accelerates context-specific enrichment analysis of experimental data with higher resolution and richer annotations. PMID:27079715

  3. Pathway analysis reveals common pro-survival mechanisms of metyrapone and carbenoxolone after traumatic brain injury.

    Directory of Open Access Journals (Sweden)

    Helen L Hellmich

    Full Text Available Developing new pharmacotherapies for traumatic brain injury (TBI requires elucidation of the neuroprotective mechanisms of many structurally and functionally diverse compounds. To test our hypothesis that diverse neuroprotective drugs similarly affect common gene targets after TBI, we compared the effects of two drugs, metyrapone (MT and carbenoxolone (CB, which, though used clinically for noncognitive conditions, improved learning and memory in rats and humans. Although structurally different, both MT and CB inhibit a common molecular target, 11β hydroxysteroid dehydrogenase type 1, which converts inactive cortisone to cortisol, thereby effectively reducing glucocorticoid levels. We examined injury-induced signaling pathways to determine how the effects of these two compounds correlate with pro-survival effects in surviving neurons of the injured rat hippocampus. We found that treatment of TBI rats with MT or CB acutely induced in hippocampal neurons transcriptional profiles that were remarkably similar (i.e., a coordinated attenuation of gene expression across multiple injury-induced cell signaling networks. We also found, to a lesser extent, a coordinated increase in cell survival signals. Analysis of injury-induced gene expression altered by MT and CB provided additional insight into the protective effects of each. Both drugs attenuated expression of genes in the apoptosis, death receptor and stress signaling pathways, as well as multiple genes in the oxidative phosphorylation pathway such as subunits of NADH dehydrogenase (Complex1, cytochrome c oxidase (Complex IV and ATP synthase (Complex V. This suggests an overall inhibition of mitochondrial function. Complex 1 is the primary source of reactive oxygen species in the mitochondrial oxidative phosphorylation pathway, thus linking the protective effects of these drugs to a reduction in oxidative stress. The net effect of the drug-induced transcriptional changes observed here indicates that

  4. Cellular and molecular mechanisms of immunomodulation in the brain through environmental enrichment

    Directory of Open Access Journals (Sweden)

    Gaurav eSinghal

    2014-04-01

    Full Text Available Recent studies on environmental enrichment (EE have shown cytokines, cellular immune components (e.g. T lymphocytes, NK cells and glial cells in causal relationship to EE in bringing out changes to neurobiology and behavior. The purpose of this review is to evaluate these neuroimmune mechanisms associated with neurobiological and behavioral changes in response to different EE methods. We systematically reviewed common research databases. After applying all inclusion and exclusion criteria, 328 articles remained for this review. Physical exercise, a form of EE, elicits anti-inflammatory and neuromodulatory effects through interaction with several immune pathways including IL-6 secretion from muscle fibers, reduced expression of TLR’s on monocytes and macrophages, reduced secretion of adipokines, modulation of hippocampal T cells, priming of microglia and upregulation of MKP-1 in CNS. In contrast, immunomodulatory roles of other enrichment methods are not studied extensively. Nonetheless, studies showing reduction in the expression of IL-1β and TNF-α in response to enrichment with novel objects and accessories suggest anti-inflammatory effects of novel environment. Likewise, social enrichment, though considered a necessity for healthy behavior, results in immunosuppression in socially defeated animals. This has been attributed to reduction in T lymphocytes, NK cells and IL-10 in subordinate animals. EE through sensory stimuli has been investigated to a lesser extent and the effect on immune factors has not been evaluated yet. Discovery of this multidimensional relationship between immune system, brain functioning and EE has paved a way towards formulating environ-immuno therapies for treating psychiatric illnesses with minimal use of pharmacotherapy. While the immuno-modulatory role of physical exercise has been evaluated extensively, more research is required to investigate neuroimmune changes associated with other enrichment methods.

  5. Toll-like receptor 4 knockout ameliorates neuroinflammation due to lung-brain interaction in mechanically ventilated mice.

    Science.gov (United States)

    Chen, Ting; Chen, Chang; Zhang, Zongze; Zou, Yufeng; Peng, Mian; Wang, Yanlin

    2016-08-01

    Toll-like receptor 4 (TLR4) is a crucial receptor in the innate immune system, and increasing evidence supports its role in inflammation, stress, and tissue injury, including injury to the lung and brain. We aimed to investigate the effects of TLR4 on neuroinflammation due to the lung-brain interaction in mechanically ventilated mice. Male wild-type (WT) C57BL/6 and TLR4 knockout (TLR4 KO) mice were divided into three groups: (1) control group (C): spontaneous breathing; (2) anesthesia group (A): spontaneous breathing under anesthesia; and (3) mechanical ventilation group (MV): 6h of MV under anesthesia. The behavioral responses of mice were tested with fear conditioning tests. The histological changes in the lung and brain were assessed using hematoxylin-eosin (HE) staining. The level of TLR4 mRNA in tissue was measured using reverse transcription-polymerase chain reaction (RT-PCR). The levels of inflammatory cytokines were measured with an enzyme-linked immunosorbent assay (ELISA). Microgliosis, astrocytosis, and the TLR4 immunoreactivity in the hippocampus were measured by double immunofluorescence. MV mice exhibited impaired cognition, and this impairment was less severe in TLR4 KO mice than in WT mice. In WT mice, MV increased TLR4 mRNA expression in the lung and brain. MV induced mild lung injury, which was prevented in TLR4 KO mice. MV mice exhibited increased levels of inflammatory cytokines, increased microglia and astrocyte activation. Microgliosis was alleviated in TLR4 KO mice. MV mice exhibited increased TLR4 immunoreactivity, which was expressed in microglia and astrocytes. These results demonstrate that TLR4 is involved in neuroinflammation due to the lung-brain interaction and that TLR4 KO ameliorates neuroinflammation due to lung-brain interaction after prolonged MV. In addition, Administration of a TLR4 antagonist (100μg/mice) to WT mice also significantly attenuated neuroinflammation of lung-brain interaction due to prolonged MV. TLR4 antagonism

  6. Molecular Mechanism of Adult Neurogenesis and its Association with Human Brain Diseases.

    Science.gov (United States)

    Liu, He; Song, Ni

    2016-01-01

    Recent advances in neuroscience challenge the old dogma that neurogenesis occurs only during embryonic development. Mounting evidence suggests that functional neurogenesis occurs throughout adulthood. This review article discusses molecular factors that affect adult neurogenesis, including morphogens, growth factors, neurotransmitters, transcription factors, and epigenetic factors. Furthermore, we summarize and compare current evidence of associations between adult neurogenesis and human brain diseases such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and brain tumors. PMID:27375363

  7. Patent foramen ovale as a preferential mechanism for increasing the likelihood of brain tumor metastasis

    OpenAIRE

    Rigatelli, Gianluca; Rossi, Andrea; Dell'Avvocata, Fabio; Cardaioli, Paolo

    2011-01-01

    Metastases are the most common tumors of the central nervous system which may lie dormant behind the brain blood- barrier sheltering from chemiotherapeutic drugs, and whose presence usually indicates a poor prognosis. Development of brain metastases includes the intravasation of the cancer cells through the tumor blood vessels, their circulation within the venous system, passing through the pulmonary filter thus reaching the systemic circulation. Patent foramen ovale (PFO) is a natural commun...

  8. Drug-Induced Apoptosis: Mechanism by which Alcohol and Many Other Drugs Can Disrupt Brain Development

    OpenAIRE

    Olney, John W.; Creeley, Catherine E.

    2013-01-01

    Maternal ingestion of alcohol during pregnancy can cause a disability syndrome termed Fetal Alcohol Spectrum Disorder (FASD), which may include craniofacial malformations, structural pathology in the brain, and a variety of long-term neuropsychiatric disturbances. There is compelling evidence that exposure to alcohol during early embryogenesis (4th week of gestation) can cause excessive death of cell populations that are essential for normal development of the face and brain. While this can e...

  9. Maintaining Brain Health by Monitoring Inflammatory Processes: a Mechanism to Promote Successful Aging

    OpenAIRE

    Rosano, Caterina; Marsland, Anna L.; Gianaros, Peter J.

    2011-01-01

    Maintaining brain health promotes successful aging. The main determinants of brain health are the preservation of cognitive function and remaining free from structural and metabolic abnormalities, including loss of neuronal synapses, atrophy, small vessel disease and focal amyloid deposits visible by neuroimaging. Promising studies indicate that these determinants are to some extent modifiable, even among adults seventy years and older. Converging animal and human evidence further suggests th...

  10. Epigenetic mechanisms and associated brain circuits in the regulation of positive emotions: A role for transposable elements.

    Science.gov (United States)

    Gaudi, Simona; Guffanti, Guia; Fallon, James; Macciardi, Fabio

    2016-10-15

    Epigenetic programming and reprogramming are at the heart of cellular differentiation and represent developmental and evolutionary mechanisms in both germline and somatic cell lines. Only about 2% of our genome is composed of protein-coding genes, while the remaining 98%, once considered "junk" DNA, codes for regulatory/epigenetic elements that control how genes are expressed in different tissues and across time from conception to death. While we already know that epigenetic mechanisms are at play in cancer development and in regulating metabolism (cellular and whole body), the role of epigenetics in the developing prenatal and postnatal brain, and in maintaining a proper brain activity throughout the various stages of life, in addition to having played a critical role in human evolution, is a relatively new domain of knowledge. Here we present the current state-of-the-art techniques and results of these studies within the domain of emotions, and then speculate on how genomic and epigenetic mechanisms can modify and potentially alter our emotional (limbic) brain and affect our social interactions. J. Comp. Neurol. 524:2944-2954, 2016. © 2016 Wiley Periodicals, Inc. PMID:27224878

  11. Mechanism of case processing in the brain: an fMRI study.

    Directory of Open Access Journals (Sweden)

    Satoru Yokoyama

    Full Text Available In sentence comprehension research, the case system, which is one of the subsystems of the language processing system, has been assumed to play a crucial role in signifying relationships in sentences between noun phrases (NPs and other elements, such as verbs, prepositions, nouns, and tense. However, so far, less attention has been paid to the question of how cases are processed in our brain. To this end, the current study used fMRI and scanned the brain activity of 15 native English speakers during an English-case processing task. The results showed that, while the processing of all cases activates the left inferior frontal gyrus and posterior part of the middle temporal gyrus, genitive case processing activates these two regions more than nominative and accusative case processing. Since the effect of the difference in behavioral performance among these three cases is excluded from brain activation data, the observed different brain activations would be due to the different processing patterns among the cases, indicating that cases are processed differently in our brains. The different brain activations between genitive case processing and nominative/accusative case processing may be due to the difference in structural complexity between them.

  12. Enriched environment decreases microglia and brain macrophages inflammatory phenotypes through adiponectin-dependent mechanisms: Relevance to depressive-like behavior.

    Science.gov (United States)

    Chabry, Joëlle; Nicolas, Sarah; Cazareth, Julie; Murris, Emilie; Guyon, Alice; Glaichenhaus, Nicolas; Heurteaux, Catherine; Petit-Paitel, Agnès

    2015-11-01

    Regulation of neuroinflammation by glial cells plays a major role in the pathophysiology of major depression. While astrocyte involvement has been well described, the role of microglia is still elusive. Recently, we have shown that Adiponectin (ApN) plays a crucial role in the anxiolytic/antidepressant neurogenesis-independent effects of enriched environment (EE) in mice; however its mechanisms of action within the brain remain unknown. Here, we show that in a murine model of depression induced by chronic corticosterone administration, the hippocampus and the hypothalamus display increased levels of inflammatory cytokines mRNA, which is reversed by EE housing. By combining flow cytometry, cell sorting and q-PCR, we show that microglia from depressive-like mice adopt a pro-inflammatory phenotype characterized by higher expression levels of IL-1β, IL-6, TNF-α and IκB-α mRNAs. EE housing blocks pro-inflammatory cytokine gene induction and promotes arginase 1 mRNA expression in brain-sorted microglia, indicating that EE favors an anti-inflammatory activation state. We show that microglia and brain-macrophages from corticosterone-treated mice adopt differential expression profiles for CCR2, MHC class II and IL-4recα surface markers depending on whether the mice are kept in standard environment or EE. Interestingly, the effects of EE were abolished when cells are isolated from ApN knock-out mouse brains. When injected intra-cerebroventricularly, ApN, whose level is specifically increased in cerebrospinal fluid of depressive mice raised in EE, rescues microglia phenotype, reduces pro-inflammatory cytokine production by microglia and blocks depressive-like behavior in corticosterone-treated mice. Our data suggest that EE-induced ApN increase within the brain regulates microglia and brain macrophages phenotype and activation state, thus reducing neuroinflammation and depressive-like behaviors in mice.

  13. BRAIN PLASTICITY: MUSICAL TRAINING INVOLVEMENT

    Directory of Open Access Journals (Sweden)

    Verónika Diaz Abrahan

    2012-12-01

    Full Text Available The main research about the effect of musical training in adult and childhood brain was revised in this work. The music realizes unique demands to our ner-vous system. This call the attention of several researchers causing, in the past years, an enhancement of the exploration about this topic; this increment was benefit for the emergence of new neuroimaging techniques, the music positioned as an investigation tool of human cognition and superior brain mechanisms. The musical perception and production are specific functions of the human brain that depend of a wide cortical-subcortical neural net distributed across both hemi-spheres and cerebellum. The main findings in this area indicated structural and functional differences in the adult and child brain due to musical training, and this is more relevant that innate properties of the subject. There is brain plasticity due to adaptive processes product of the environmental stimulation.

  14. Integrative understanding of emergent brain properties, quantum brain hypotheses and connectome alterations in dementia are key challenges to conquer Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Rodrigo O Kuljiš

    2010-08-01

    Full Text Available The biological substrate for cognition remains a challenge as much as defining this function of living beings. Here, we examine some of the challenges to understand normal and disordered cognition in humans. We use aspects of Alzheimer’s disease and related disorders to illustrate how the wealth of information at many conceptually separate, even decoupled, physical scales — in particular at the Molecular Neuroscience versus Systems Neuroscience/Neuropsychology levels — presents a challenge in terms of true interdisciplinary integration towards a coherent understanding. These unresolved dilemmas include critically the as yet untested Quantum Brain hypothesis, and the embryonic attempts to develop and define the so-called Connectome in humans and in non-human models of disease. To mitigate these challenges, we propose a scheme incorporating the vast array of scales of the space and time (space-time manifold from at least the subatomic through cognitive-behavioral dimensions of inquiry, to achieve a new understanding of both normal and disordered cognition, that is essential for a new era of progress in the Generative Sciences and its application to translational efforts for disease prevention and treatment.

  15. Effect of a water-maze procedure on the redox mechanisms in brain parts of aged rats

    Directory of Open Access Journals (Sweden)

    Natalia Andreevna Krivova

    2015-03-01

    Full Text Available The Morris water maze (MWM is a tool for assessment of age-related cognitive deficits. In our work, MWM was used for appraisal of cognitive deficits in 11-month-old rats and investigation of the effect exerted by training in the Morris water maze on the redox mechanisms in rat brain parts. Young adult (3-month-old and aged (11-month-old male rats were trained in the water maze. Intact animals of the corresponding age were used as the reference groups. The level of pro- and antioxidant capacity in brain tissue homogenates was assessed using the chemiluminescence method.Cognitive deficits were found in 11-month-old rats: at the first day of training they showed only 30% of successful MWM trials. However, at the last training day the percentage of successful trials was equal for young adult and aged animals. This indicates that cognitive deficits in aged rats can be reversed by MWM training. Therewith, the MWM spatial learning procedure itself produces changes in different processes of redox homeostasis in 11-month-old and 3-month-old rats as compared to intact animals. Young adult rats showed a decrease in prooxidant capacity in all brain parts, while 11-month-old rats demonstrated an increase in antioxidant capacity in the olfactory bulb, pons + medulla oblongata and frontal lobe cortex. Hence, the MWM procedure activates the mechanisms that restrict the oxidative stress in brain parts. The obtained results may be an argument for further development of the animal training procedures aimed to activate the mechanisms responsible for age-related cognitive deficits. This may be useful not only for the development of training procedures applicable to human patients with age-related cognitive impairments, but also for their rehabilitation.

  16. Emergence of overlap in ensembles of spatial multiplexes and statistical mechanics of spatial interacting networks ensembles

    CERN Document Server

    Halu, Arda; Bianconi, Ginestra

    2013-01-01

    Spatial networks range from the brain networks, to transportation networks and infrastructures. Recently interacting and multiplex networks are attracting great attention because their dynamics and robustness cannot be understood without treating at the same time several networks. Here we present maximal entropy ensembles of spatial multiplex and spatial interacting networks that can be used in order to model spatial multilayer network structures and to build null models of real datasets. We show that spatial multiplex naturally develop a significant overlap of the links, a noticeable property of many multiplexes that can affect significantly the dynamics taking place on them. Additionally, we characterize ensembles of spatial interacting networks and we analyse the structure of interacting airport and railway networks in India, showing the effect of space in determining the link probability.

  17. Mechanisms and dynamics of cooperation and competition emergence in complex networked systems

    Science.gov (United States)

    Gianetto, David A.

    Cooperative behavior is a pervasive phenomenon in human interactions and yet how it can evolve and become established, through the selfish process of natural selection, is an enduring puzzle. These behaviors emerge when agents interact in a structured manner; even so, the key structural factors that affect cooperation are not well understood. Moreover, the literature often considers cooperation a single attribute of primitive agents who do not react to environmental changes but real-world actors are more perceptive. The present work moves beyond these assumptions by evolving more realistic game participants, with memories of the past, on complex networks. Agents play repeated games with a three-part Markovian strategy that allows us to separate the cooperation phenomenon into trust, reciprocity, and forgiveness characteristics. Our results show that networks matter most when agents gain the most by acting in a selfish manner, irrespective of how much they may lose by cooperating; since the context provided by neighborhoods inhibits greedy impulses that agents otherwise succumb to in isolation. Network modularity is the most important driver of cooperation emergence in these high-stakes games. However, modularity fails to tell the complete story. Modular scale-free graphs impede cooperation when close coordination is required, partially due to the acyclic nature of scale-free network models. To achieve the highest cooperation in diverse social conditions, both high modularity, low connectivity within modules, and a rich network of long cycles become important. With these findings in hand, we study the influence of networks on coordination and competition within the federal health care insurance exchange. In this applied study, we show that systemic health care coordination is encouraged by the emergent insurance network. The network helps underpin the viability of the exchange and provides an environment of stronger competition once a critical-mass of insurers have

  18. Research on Heat-Mechanical Coupling of Ventilated Disc Brakes under the Condition of Emergency Braking

    Science.gov (United States)

    Tan, Xuelong; Zhang, Jian; Tang, Wenxian; Zhang, Yang

    Taking the ventilated disc brake in some company as research object, and using UG to build 3D models of brake disc and pad, and making use of ABAQUS/Standard to set up two parts' finite element model, via the decelerated motion of actual simulation brake disc, which gets ventilated disc brake in the case of emergency breaking in time and space distribution of conditions of temperature and stress field, summarizes the distribution of temperature field and stress field, proves complex coupling between temperature, stress, and supplies the direct basis for brake's fatigue life analysis.

  19. Alien Hand, Restless Brain: Salience Network and Interhemispheric Connectivity Disruption Parallel Emergence and Extinction of Diagonistic Dyspraxia.

    Science.gov (United States)

    Ridley, Ben; Beltramone, Marion; Wirsich, Jonathan; Le Troter, Arnaud; Tramoni, Eve; Aubert, Sandrine; Achard, Sophie; Ranjeva, Jean-Philippe; Guye, Maxime; Felician, Olivier

    2016-01-01

    Diagonistic dyspraxia (DD) is by far the most spectacular manifestation reported by sufferers of acute corpus callosum (CC) injury (so-called "split-brain"). In this form of alien hand syndrome, one hand acts at cross purposes with the other "against the patient's will". Although recent models view DD as a disorder of motor control, there is still little information regarding its neural underpinnings, due to widespread connectivity changes produced by CC insult, and the obstacle that non-volitional movements represent for task-based functional neuroimaging studies. Here, we studied patient AM, the first report of DD in patient with complete developmental CC agenesis. This unique case also offers the opportunity to study the resting-state connectomics of DD in the absence of diffuse changes subsequent to CC injury or surgery. AM developed DD following status epilepticus (SE) which resolved over a 2-year period. Whole brain functional connectivity (FC) was compared (Crawford-Howell [CH]) to 16 controls during the period of acute DD symptoms (Time 1) and after remission (Time 2). Whole brain graph theoretical models were also constructed and topological efficiency examined. At Time 1, disrupted FC was observed in inter-hemispheric and intra-hemispheric right edges, involving frontal superior and midline structures. Graph analysis indicated disruption of the efficiency of salience and right frontoparietal (FP) networks. At Time 2, after remission of diagnostic dyspraxia symptoms, FC and salience network changes had resolved. In sum, longitudinal analysis of connectivity in AM indicates that DD behaviors could result from disruption of systems that support the experience and control of volitional movements and the ability to generate appropriate behavioral responses to salient stimuli. This also raises the possibility that changes to large-scale functional architecture revealed by resting-state functional magnetic resonance imaging (fMRI) (rs-fMRI) may provide relevant

  20. Use of biomarker S100B for traumatic brain damage in the emergency department may change observation strategy

    DEFF Research Database (Denmark)

    Hansen-Schwartz, Jacob; Bouchelouche, Pierre Nourdine

    2014-01-01

    INTRODUCTION: The revised Scandinavian Neurotrauma Committee (SNC) guidelines on management of patients with head trauma include an option for measurement of S100B in peripheral blood with 100% sensitivity for neurosurgical intervention. A medical technology assessment was conducted to evaluate any...... impact of using S100B on the use of computed tomographies (CT) of the brain and admission for observation. MATERIAL AND METHODS: Patients referred for assessment of head injury over a period of 1.5 months had their blood sampled for measurement of S100B in serum. Results were not available...

  1. Proceedings of the Third Annual Deep Brain Stimulation Think Tank: A Review of Emerging Issues and Technologies.

    Science.gov (United States)

    Rossi, P Justin; Gunduz, Aysegul; Judy, Jack; Wilson, Linda; Machado, Andre; Giordano, James J; Elias, W Jeff; Rossi, Marvin A; Butson, Christopher L; Fox, Michael D; McIntyre, Cameron C; Pouratian, Nader; Swann, Nicole C; de Hemptinne, Coralie; Gross, Robert E; Chizeck, Howard J; Tagliati, Michele; Lozano, Andres M; Goodman, Wayne; Langevin, Jean-Philippe; Alterman, Ron L; Akbar, Umer; Gerhardt, Greg A; Grill, Warren M; Hallett, Mark; Herrington, Todd; Herron, Jeffrey; van Horne, Craig; Kopell, Brian H; Lang, Anthony E; Lungu, Codrin; Martinez-Ramirez, Daniel; Mogilner, Alon Y; Molina, Rene; Opri, Enrico; Otto, Kevin J; Oweiss, Karim G; Pathak, Yagna; Shukla, Aparna; Shute, Jonathan; Sheth, Sameer A; Shih, Ludy C; Steinke, G Karl; Tröster, Alexander I; Vanegas, Nora; Zaghloul, Kareem A; Cendejas-Zaragoza, Leopoldo; Verhagen, Leonard; Foote, Kelly D; Okun, Michael S

    2016-01-01

    The proceedings of the 3rd Annual Deep Brain Stimulation Think Tank summarize the most contemporary clinical, electrophysiological, imaging, and computational work on DBS for the treatment of neurological and neuropsychiatric disease. Significant innovations of the past year are emphasized. The Think Tank's contributors represent a unique multidisciplinary ensemble of expert neurologists, neurosurgeons, neuropsychologists, psychiatrists, scientists, engineers, and members of industry. Presentations and discussions covered a broad range of topics, including policy and advocacy considerations for the future of DBS, connectomic approaches to DBS targeting, developments in electrophysiology and related strides toward responsive DBS systems, and recent developments in sensor and device technologies. PMID:27092042

  2. Neural Operant Conditioning as a Core Mechanism of Brain-Machine Interface Control

    Directory of Open Access Journals (Sweden)

    Yoshio Sakurai

    2016-08-01

    Full Text Available The process of changing the neuronal activity of the brain to acquire rewards in a broad sense is essential for utilizing brain-machine interfaces (BMIs, which is essentially operant conditioning of neuronal activity. Currently, this is also known as neural biofeedback, and it is often referred to as neurofeedback when human brain activity is targeted. In this review, we first illustrate biofeedback and operant conditioning, which are methodological background elements in neural operant conditioning. Then, we introduce research models of neural operant conditioning in animal experiments and demonstrate that it is possible to change the firing frequency and synchronous firing of local neuronal populations in a short time period. We also debate the possibility of the application of neural operant conditioning and its contribution to BMIs.

  3. Mechanisms of restriction of viral neuroinvasion at the blood-brain barrier.

    Science.gov (United States)

    Miner, Jonathan J; Diamond, Michael S

    2016-02-01

    The blood-brain barrier (BBB) consists of highly specialized cells including brain microvascular endothelial cells, astrocytes, microglia, pericytes, and neurons, which act in concert to restrict the entry of pathogens, immune cells, and soluble molecules into the central nervous system (CNS). If pathogens manage to cross the BBB and establish infection within the CNS, the BBB can open in a regulated manner to allow leukocyte transmigration into the CNS so that microbes, infected cells, and debris can be cleared. This review highlights how different inflammatory cytokines or signaling pathways disrupt or enhance BBB integrity in a way that regulates entry of neurotropic viruses into the CNS.

  4. Emergence of cytotoxic resistance in cancer cell populations: Single-cell mechanisms and population-level consequences

    Science.gov (United States)

    Lorenzi, Tommaso; Chisholm, Rebecca H.; Lorz, Alexander; Larsen, Annette K.; de Almeida, Luís Neves; Escargueil, Alexandre; Clairambault, Jean

    2016-06-01

    We formulate an individual-based model and a population model of phenotypic evolution, under cytotoxic drugs, in a cancer cell population structured by the expression levels of survival-potential and proliferation-potential. We apply these models to a recently studied experimental system. Our results suggest that mechanisms based on fundamental laws of biology can reversibly push an actively-proliferating, and drug-sensitive, cell population to transition into a weakly-proliferative and drug-tolerant state, which will eventually facilitate the emergence of more potent, proliferating and drug-tolerant cells.

  5. Sub-Quantum Thermodynamics as a Basis of Emergent Quantum Mechanics

    Directory of Open Access Journals (Sweden)

    Gerhard Grössing

    2010-09-01

    Full Text Available This review presents results obtained from our group’s approach to model quantum mechanics with the aid of nonequilibrium thermodynamics. As has been shown, the exact Schrödinger equation can be derived by assuming that a particle of energy  is actually a dissipative system maintained in a nonequilibrium steady state by a constant throughput of energy (heat flow. Here, also other typical quantum mechanical features are discussed and shown to be completely understandable within our approach, i.e., on the basis of the assumed sub-quantum thermodynamics. In particular, Planck’s relation for the energy of a particle, the Heisenberg uncertainty relations, the quantum mechanical superposition principle and Born’s rule, or the “dispersion of the Gaussian wave packet”, a.o., are all explained on the basis of purely classical physics.

  6. Introduction to Brain mechanisms of selective perception and action. Proceedings of a Discussion Meeting held at the Royal Society of London on 19 and 20 November 1997.

    OpenAIRE

    Humphreys, G.W.

    1998-01-01

    Introduction to Brain mechanisms of selective perception and action. Proceedings of a Discussion Meeting held at the Royal Society of London on 19 and 20 November 1997. Organized and edited by G. W. Humphreys, J. Duncan and A. Treisman.

  7. On the molecular mechanisms driving pain perception and emergent collective behaviors

    Science.gov (United States)

    Di Patti, F.; Fanelli, D.

    2010-05-01

    A stochastic model to investigate the microscopic processes which trigger the sensation of pain is considered. The model, presented in Di Patti and Fanelli [Di Patti F, Fanelli D. Can a microscopic stochastic model explain the emergence of pain cycles in patients? J Stat Mech 2009. doi:10.1088/1742-5468/2009/01/P01004], accounts for the action of analgesic drug and introduces an effect of competition with the inactive species populating the bloodstream. Regular oscillations in the amount of bound receptors are detected, following a resonant amplification of the stochastic component intrinsic to the system. The condition for such oscillations to occur are here studied, resorting to combined numerical and analytical techniques. Extended and connected patches of the admissible parameters space are detected which do correspond to the oscillatory behaviors. These findings are discussed with reference to the existing literature on patients' response to the analgesic treatment.

  8. 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

  9. 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

  10. Gene × Smoking Interactions on Human Brain Gene Expression: Finding Common Mechanisms in Adolescents and Adults

    Science.gov (United States)

    Wolock, Samuel L.; Yates, Andrew; Petrill, Stephen A.; Bohland, Jason W.; Blair, Clancy; Li, Ning; Machiraju, Raghu; Huang, Kun; Bartlett, Christopher W.

    2013-01-01

    Background: Numerous studies have examined gene × environment interactions (G × E) in cognitive and behavioral domains. However, these studies have been limited in that they have not been able to directly assess differential patterns of gene expression in the human brain. Here, we assessed G × E interactions using two publically available datasets…

  11. Dual Mechanism of Brain Injury and Novel Treatment Strategy in Maple Syrup Urine Disease

    Science.gov (United States)

    Zinnanti, William J.; Lazovic, Jelena; Griffin, Kathleen; Skvorak, Kristen J.; Paul, Harbhajan S.; Homanics, Gregg E.; Bewley, Maria C.; Cheng, Keith C.; LaNoue, Kathryn F.; Flanagan, John M.

    2009-01-01

    Maple syrup urine disease (MSUD) is an inherited disorder of branched-chain amino acid metabolism presenting with life-threatening cerebral oedema and dysmyelination in affected individuals. Treatment requires life-long dietary restriction and monitoring of branched-chain amino acids to avoid brain injury. Despite careful management, children…

  12. Clinical Outcome and Mechanisms of Deep Brain Stimulation for Obsessive-Compulsive Disorder

    NARCIS (Netherlands)

    van Westen, Maarten; Rietveld, Erik; Figee, Martijn; Denys, D.

    2015-01-01

    Clinical outcome of deep brain stimulation (DBS) for obsessive-compulsive disorder (OCD) shows robust effects in terms of a mean Yale-Brown Obsessive-Compulsive Scale (YBOCS) reduction of 47.7 % and a mean response percentage (minimum 35 % YBOCS reduction) of 58.2 %. It appears that most patients re

  13. Evolution of time-keeping mechanisms : early emergence and adaptation to photoperiod

    NARCIS (Netherlands)

    Hut, R. A.; Beersma, D. G. M.

    2011-01-01

    Virtually all species have developed cellular oscillations and mechanisms that synchronize these cellular oscillations to environmental cycles. Such environmental cycles in biotic (e. g. food availability and predation risk) or abiotic (e. g. temperature and light) factors may occur on a daily, annu

  14. The role of programmed and emergent mechanisms of coordination: How standardized care pathways contribute to coordinate care tasks in hospitals

    DEFF Research Database (Denmark)

    Prætorius, Thim

    Hospitals face substantial coordination challenges. To meet this hospitals more and more use standardized work processes such as care pathways. By drawing on recent coordination theory that increasingly emphasizes the role of lateral and emergent interactions alongside traditional, programmed...... mechanisms of coordination, this paper finds that standardized work processes such as care pathways should be considered as a bundle of coordination mechanisms—plans and rules, objects, routines, roles and proximity—rather than a mechanism of its own. The bundle builds the accountability, predictability...... and common understanding needed to coordinate standardized care tasks. The analysis lends theoretical insights to the traditional view that see standardized work processes as programmed processes. For health care workers who design, implement and use care pathways to solve care tasks, the analysis calls...

  15. Epigenetic mechanisms: An emerging role in pathogenesis and its therapeutic potential in systemic sclerosis.

    Science.gov (United States)

    Luo, Yangyang; Wang, Yong; Shu, Ye; Lu, Qianjin; Xiao, Rong

    2015-10-01

    Systemic sclerosis (SSc) is a heterogeneous and life-threatening autoimmune disease characterized by damage to small blood vessels, interruption of immune homeostasis and ultimately, fibrosis. Currently, the mechanisms involved in SSc pathogenesis remain unknown. An increasing amount of data shows that, via certain signaling pathways, epigenetic mechanisms, including DNA methylation, histone modification, and miRNAs, are closely related to the three primary processes that characterize SSc: vascular abnormalities, activation of immune system, and excessive extracellular matrix deposition. In the clinical setting, identification of molecules and biomarkers for determining disease severity, predicting disease progression and assessing response to treatment remains challenging. In this review, we aim to summarize the key epigenetic mechanisms involved in the pathogenesis of SSc. Certain cytokines or molecules, such as CD40, CD70, and Fli-1, are expressed at varying rates in SSc due to epigenetic modification and play important roles in SSc. It is therefore likely that these molecules may be biomarkers for SSc. In addition, epigenetic changes of certain genes, including Fli-1, BMPRII, CD11a, Foxp3, and eNOS, influence the expression of these genes to ultimately result in an anti-fibrotic effect. The influence that epigenetics has on SSc pathogenesis suggests that epigenetics-targeting drugs may have potential therapeutic effects against SSc. This article is part of a Directed Issue entitled: Epigenetics dynamics in development and disease.

  16. Epigenetic mechanisms in non-alcoholic fatty liver disease:An emerging field

    Institute of Scientific and Technical Information of China (English)

    Rocío; Gallego-Durán; Manuel; Romero-Gómez

    2015-01-01

    Non-alcoholic fatty liver disease(NAFLD) is an emerging health concern in both developed and non-developed world, encompassing from simple steatosis to nonalcoholic steatohepatitis(NASH), cirrhosis and liver cancer. Incidence and prevalence of this disease are increasing due to the socioeconomic transition and change to harmful diet. Currently, gold standard method in NAFLD diagnosis is liver biopsy, despite complications and lack of accuracy due to sampling error. Further, pathogenesis of NAFLD is not fully understood, but is well-known that obesity, diabetes and metabolic derangements played a major role in disease development and progression. Besides, gut microbioma and host genetic and epigenetic background could explain considerable interindividual variability. Knowledge that epigenetics, heritable events not caused by changes in DNA sequence, contribute to development of diseases has been a revolution in the last few years. Recently, evidences are accumulating revealing the important role of epigenetics in NAFLD pathogenesis and in NASH genesis. Histone modifications, changes in DNA methylation and aberrant profiles or micro RNAs could boost development of NAFLD and transition into clinical relevant status. PNPLA3 genotype GG has been associated with a more progressive disease and epigenetics could modulate this effect. The impact of epigenetic on NAFLD progression could deserve further applications on therapeutic targets together with future non-invasive methods useful for the diagnosis and staging of NAFLD.

  17. Neuroimaging mechanisms of change in psychotherapy for addictive behaviors: Emerging translational approaches that bridge biology and behavior: Introduction to the Special Issue

    OpenAIRE

    Feldstein Ewing, Sarah W.; Chung, Tammy

    2013-01-01

    Research on mechanisms of behavior change provides an innovative method to improve treatment for addictive behaviors. An important extension of mechanisms of change research involves the use of translational approaches, which examine how basic biological (i.e., brain-based mechanisms) and behavioral factors interact in initiating and sustaining positive behavior change as a result of psychotherapy. Articles in this special issue include integrative conceptual reviews and innovative empirical ...

  18. Brain circuitry outside the synaptic cleft

    OpenAIRE

    Rusakov, Dmitri A.; Alexander E Dityatev

    2014-01-01

    A growing body of experimental evidence suggests that astroglia, and possibly microglia, play an important part in regulating synaptic networking of the brain. It has also emerged that extracellular matrix (ECM) structures that enwrap synaptic connections can generate molecular signals affecting both neuronal and glial activity. Thus it appears that the mechanism of information processing in the brain, which has hitherto been associated almost exclusively with neural circuits, could also invo...

  19. Brain mechanisms of hypoxic preconditioning%低氧预适应的脑机制

    Institute of Scientific and Technical Information of China (English)

    吕国蔚; 崔秀玉; 赵兰峰; 安仰原; 高翠英

    2004-01-01

    A concept ot tissue adaptation to hypoxia( i.e. hypoxic preconditioning) was developed and its corresponding animal models were reproduced in 1966s. The methods of model reproduction in rat, rabbit, and mouse in particular and the main results are brifly introduced in this review. The tolerance to hypoxia o{ preconditioned animals is significantly increased. Regular changes in animals' behavior, neurophysiology, respiratory and circulatory physiology, neuromorphology in vivo and {unction of brain and spinal cord in vitro are briefly demonstrated. The protective effects in vivo and in vitro of homogenate extract taken from the brain o{ preconditioned animals, neurochemcals and molecular neurobiolcgical alterations are briefly presented. The essence and significance of tissue adaption to hypoxia/hypoxic preconditioning are discussed in the review in terms of evolution and practical implication.

  20. Holographic View of the Brain Memory Mechanism Based on Evanescent Superluminal Photons

    Directory of Open Access Journals (Sweden)

    Takaaki Musha

    2012-08-01

    Full Text Available D. Pollen and M. Trachtenberg proposed the holographic brain theory to help explain the existence of photographic memories in some people. They suggested that such individuals had more vivid memories because they somehow could access a very large region of their memory holograms. Hameroff suggested in his paper that cylindrical neuronal microtubule cavities, or centrioles, function as waveguides for the evanescent photons for quantum signal processing. The supposition is that microtubular structures of the brain function as a coherent fiber bundle set used to store holographic images, as would a fiber-optic holographic system. In this paper, the author proposes that superluminal photons propagating inside the microtubules via evanescent waves could provide the access needed to record or retrieve a quantum coherent entangled holographic memory.

  1. Brain mechanisms of male sexual function%男性性活动相关的脑机制

    Institute of Scientific and Technical Information of China (English)

    王营; 窦鑫; 李俊发

    2011-01-01

    本文从正常性功能的脑机制、性功能障碍的脑机制以及药物治疗机制等几个方面综述了近年来男性性相关的脑成像研究.研究发现男性性活动兴奋期、平台期和高潮期由不同脑区构成的神经网络控制.其中,间脑转换区在男性射精中发挥了关键的启动作用.男性性功能障碍患者在性唤起时存在眶额回和额下回的异常激活模式.血清睾酮和脱水吗啡等药物治疗性功能障碍时,主要通过改变眶额回、脑岛、屏状核和颞下回的激活状态来发挥作用.%In this paper, we reviewed the brain imaging studies of male sexual function in recent years from three aspects: the brain mechanism of normal sexual function, the brain mechanism of sexual dysfunction, and the mechanism of drug therapy for sexual dysfunction. Studies show that the development stages of male sexual activities, such as the excitement phase, plateau phase and orgasm phase, are controlled by different neural networks. The mesodiencephalic transition zone may play an important role in the startup of male ejaculation. There are significant differences between sexual dysfunction males and normal males in activation patterns of the brain in sexual arousal. The medial orbitofrontal cortex and inferior frontal gyrus in the abnormal activation pattern are correlated with sexual dysfunction males in sexual arousal. Serum testosterone and morphine are commonly used drugs for male sexual dysfunction,whose mechanisms are to alter the activating levels of the medial orbitofrontal cortex, insula, claustrum and inferior temporal gyrus.Natl J Androl, 2011, 17 (8): 739-743

  2. Neuropharmacology – Special Issue on Cerebral Ischemia Mechanisms of Ischemic Brain Damage – Review Article

    OpenAIRE

    Doyle, Kristian P.; Simon, Roger P.; Stenzel-Poore, Mary P

    2008-01-01

    Each year in the United States approximately 700,000 individuals are afflicted with a stroke and currently there are almost 2 million survivors of stroke living in the US with prolonged disability. In China 1.5 million people die from stroke each year and in developed nations stroke is the third leading cause of death, only surpassed by heart disease and cancer. Brain injury following stroke results from the complex interplay of multiple pathways including excitotoxicity, acidotoxicity, ionic...

  3. Decoding brain state transitions in the pedunculopontine nucleus: cooperative phasic and tonic mechanisms.

    Science.gov (United States)

    Petzold, Anne; Valencia, Miguel; Pál, Balázs; Mena-Segovia, Juan

    2015-01-01

    Cholinergic neurons of the pedunculopontine nucleus (PPN) are most active during the waking state. Their activation is deemed to cause a switch in the global brain activity from sleep to wakefulness, while their sustained discharge may contribute to upholding the waking state and enhancing arousal. Similarly, non-cholinergic PPN neurons are responsive to brain state transitions and their activation may influence some of the same targets of cholinergic neurons, suggesting that they operate in coordination. Yet, it is not clear how the discharge of distinct classes of PPN neurons organize during brain states. Here, we monitored the in vivo network activity of PPN neurons in the anesthetized rat across two distinct levels of cortical dynamics and their transitions. We identified a highly structured configuration in PPN network activity during slow-wave activity that was replaced by decorrelated activity during the activated state (AS). During the transition, neurons were predominantly excited (phasically or tonically), but some were inhibited. Identified cholinergic neurons displayed phasic and short latency responses to sensory stimulation, whereas the majority of non-cholinergic showed tonic responses and remained at high discharge rates beyond the state transition. In vitro recordings demonstrate that cholinergic neurons exhibit fast adaptation that prevents them from discharging at high rates over prolonged time periods. Our data shows that PPN neurons have distinct but complementary roles during brain state transitions, where cholinergic neurons provide a fast and transient response to sensory events that drive state transitions, whereas non-cholinergic neurons maintain an elevated firing rate during global activation.

  4. Decoding brain state transitions in the pedunculopontine nucleus: cooperative phasic and tonic mechanisms

    Directory of Open Access Journals (Sweden)

    Anne ePetzold

    2015-10-01

    Full Text Available Cholinergic neurons of the pedunculopontine nucleus (PPN are most active during the waking state. Their activation is deemed to cause a switch in the global brain activity from sleep to wakefulness, while their sustained discharge may contribute to upholding the waking state and enhancing arousal. Similarly, non-cholinergic PPN neurons are responsive to brain state transitions and their activation may influence some of the same targets of cholinergic neurons, suggesting that they operate in coordination. Yet, it is not clear how the discharge of distinct classes of PPN neurons organize during brain states. Here we monitored the in vivo network activity of PPN neurons in the anesthetized rat across two distinct levels of cortical dynamics and their transitions. We identified a highly structured configuration in PPN network activity during slow-wave activity that was replaced by decorrelated activity during the activated state. During the transition, neurons were predominantly excited (phasically or tonically, but some were inhibited. Identified cholinergic neurons displayed phasic and short latency responses to sensory stimulation, whereas the majority of non-cholinergic showed tonic responses and remained at high discharge rates beyond the state transition. In vitro recordings demonstrate that cholinergic neurons exhibit fast adaptation that prevents them from discharging at high rates over prolonged time periods. Our data shows that PPN neurons have distinct but complementary roles during brain state transitions, where cholinergic neurons provide a fast and transient response to sensory events that drive state transitions, whereas non-cholinergic neurons maintain an elevated firing rate during global activation.

  5. Effect of Heavy Ion Brain Radiation on Nerve-immune System Regulation Mechanism in Rat

    Institute of Scientific and Technical Information of China (English)

    YU; Ying-qi; WANG; Xiao; KONG; Fu-quan; SUI; Li; LEI; Run-hong; MA; Hong; DENG; Yu-lin; LI; Qiang

    2013-01-01

    High-dose ionizing irradiation can cause extensive injuries in susceptible tissues.Blood,nervous and immune systems are highly radiation-sensitive.While the nerve-immune system regulation of radiationdamage in the relevant research is rare.So the brain injury model that rats were subjected to 15 Gy of head irradiation was built.By detecting hypothalamic-pituitary-adrenal axis(HPA axis)changes,the

  6. Decoding brain state transitions in the pedunculopontine nucleus: cooperative phasic and tonic mechanisms

    Science.gov (United States)

    Petzold, Anne; Valencia, Miguel; Pál, Balázs; Mena-Segovia, Juan

    2015-01-01

    Cholinergic neurons of the pedunculopontine nucleus (PPN) are most active during the waking state. Their activation is deemed to cause a switch in the global brain activity from sleep to wakefulness, while their sustained discharge may contribute to upholding the waking state and enhancing arousal. Similarly, non-cholinergic PPN neurons are responsive to brain state transitions and their activation may influence some of the same targets of cholinergic neurons, suggesting that they operate in coordination. Yet, it is not clear how the discharge of distinct classes of PPN neurons organize during brain states. Here, we monitored the in vivo network activity of PPN neurons in the anesthetized rat across two distinct levels of cortical dynamics and their transitions. We identified a highly structured configuration in PPN network activity during slow-wave activity that was replaced by decorrelated activity during the activated state (AS). During the transition, neurons were predominantly excited (phasically or tonically), but some were inhibited. Identified cholinergic neurons displayed phasic and short latency responses to sensory stimulation, whereas the majority of non-cholinergic showed tonic responses and remained at high discharge rates beyond the state transition. In vitro recordings demonstrate that cholinergic neurons exhibit fast adaptation that prevents them from discharging at high rates over prolonged time periods. Our data shows that PPN neurons have distinct but complementary roles during brain state transitions, where cholinergic neurons provide a fast and transient response to sensory events that drive state transitions, whereas non-cholinergic neurons maintain an elevated firing rate during global activation. PMID:26582977

  7. A modified controlled cortical impact technique to model mild traumatic brain injury mechanics in mice.

    Directory of Open Access Journals (Sweden)

    YungChia eChen

    2014-06-01

    Full Text Available For the past 25 years, controlled cortical impact (CCI has been a useful tool in traumatic brain injury (TBI research, creating injury patterns that include primary contusion, neuronal loss, and traumatic axonal damage. However, when CCI was first developed, very little was known on the underlying biomechanics of mild TBI. This paper uses information generated from recent computational models of mild TBI in humans to alter CCI and better reflect the biomechanical conditions of mild TBI. Using a finite element model of CCI in the mouse, we adjusted three primary features of CCI: the speed of the impact to achieve strain rates within the range associated with mild TBI, the shape and material of the impounder to minimize strain concentrations in the brain, and the impact depth to control the peak deformation that occurred in the cortex and hippocampus. For these modified cortical impact conditions, we observed peak strains and strain rates throughout the brain were significantly reduced and consistent with estimated strains and strain rates observed in human mild TBI. We saw breakdown of the blood-brain barrier but no primary hemorrhage. Moreover, neuronal degeneration, axonal injury, and both astrocytic and microglia reactivity were observed up to 8 days after injury. Significant deficits in rotarod performance appeared early after injury, but we observed no impairment in spatial object recognition or contextual fear conditioning response 5 days and 8 days after injury, respectively. Together, these data show that simulating the biomechanical conditions of mild TBI with a modified cortical impact technique produces regions of cellular reactivity and neuronal loss that coincide with only a transient behavioral impairment.

  8. From stimuli to motor responses : Decoding rules and decision mechanisms in the human brain

    OpenAIRE

    Bode, S

    2010-01-01

    In a dynamically changing environment, we are constantly required to flexibly react to stimuli. It is therefore necessary to adapt behaviour to environmental cues, as well as to successfully perceive relevant stimuli. The present work addressed the question of which brain areas form the basis for task preparation and decisions along the processing chain from stimuli to responses. It combined functional magnetic resonance imaging with multivariate pattern classification to search for the encod...

  9. State and Training Effects of Mindfulness Meditation on Brain Networks Reflect Neuronal Mechanisms of Its Antidepressant Effect

    Directory of Open Access Journals (Sweden)

    Chuan-Chih Yang

    2016-01-01

    Full Text Available The topic of investigating how mindfulness meditation training can have antidepressant effects via plastic changes in both resting state and meditation state brain activity is important in the rapidly emerging field of neuroplasticity. In the present study, we used a longitudinal design investigating resting state fMRI both before and after 40 days of meditation training in 13 novices. After training, we compared differences in network connectivity between rest and meditation using common resting state functional connectivity methods. Interregional methods were paired with local measures such as Regional Homogeneity. As expected, significant differences in functional connectivity both between states (rest versus meditation and between time points (before versus after training were observed. During meditation, the internal consistency in the precuneus and the temporoparietal junction increased, while the internal consistency of frontal brain regions decreased. A follow-up analysis of regional connectivity of the dorsal anterior cingulate cortex further revealed reduced connectivity with anterior insula during meditation. After meditation training, reduced resting state functional connectivity between the pregenual anterior cingulate and dorsal medical prefrontal cortex was observed. Most importantly, significantly reduced depression/anxiety scores were observed after training. Hence, these findings suggest that mindfulness meditation might be of therapeutic use by inducing plasticity related network changes altering the neuronal basis of affective disorders such as depression.

  10. State and Training Effects of Mindfulness Meditation on Brain Networks Reflect Neuronal Mechanisms of Its Antidepressant Effect

    Science.gov (United States)

    Yang, Chuan-Chih; Barrós-Loscertales, Alfonso; Pinazo, Daniel; Ventura-Campos, Noelia; Borchardt, Viola; Bustamante, Juan-Carlos; Rodríguez-Pujadas, Aina; Fuentes-Claramonte, Paola; Balaguer, Raúl; Ávila, César; Walter, Martin

    2016-01-01

    The topic of investigating how mindfulness meditation training can have antidepressant effects via plastic changes in both resting state and meditation state brain activity is important in the rapidly emerging field of neuroplasticity. In the present study, we used a longitudinal design investigating resting state fMRI both before and after 40 days of meditation training in 13 novices. After training, we compared differences in network connectivity between rest and meditation using common resting state functional connectivity methods. Interregional methods were paired with local measures such as Regional Homogeneity. As expected, significant differences in functional connectivity both between states (rest versus meditation) and between time points (before versus after training) were observed. During meditation, the internal consistency in the precuneus and the temporoparietal junction increased, while the internal consistency of frontal brain regions decreased. A follow-up analysis of regional connectivity of the dorsal anterior cingulate cortex further revealed reduced connectivity with anterior insula during meditation. After meditation training, reduced resting state functional connectivity between the pregenual anterior cingulate and dorsal medical prefrontal cortex was observed. Most importantly, significantly reduced depression/anxiety scores were observed after training. Hence, these findings suggest that mindfulness meditation might be of therapeutic use by inducing plasticity related network changes altering the neuronal basis of affective disorders such as depression. PMID:26998365

  11. State and Training Effects of Mindfulness Meditation on Brain Networks Reflect Neuronal Mechanisms of Its Antidepressant Effect.

    Science.gov (United States)

    Yang, Chuan-Chih; Barrós-Loscertales, Alfonso; Pinazo, Daniel; Ventura-Campos, Noelia; Borchardt, Viola; Bustamante, Juan-Carlos; Rodríguez-Pujadas, Aina; Fuentes-Claramonte, Paola; Balaguer, Raúl; Ávila, César; Walter, Martin

    2016-01-01

    The topic of investigating how mindfulness meditation training can have antidepressant effects via plastic changes in both resting state and meditation state brain activity is important in the rapidly emerging field of neuroplasticity. In the present study, we used a longitudinal design investigating resting state fMRI both before and after 40 days of meditation training in 13 novices. After training, we compared differences in network connectivity between rest and meditation using common resting state functional connectivity methods. Interregional methods were paired with local measures such as Regional Homogeneity. As expected, significant differences in functional connectivity both between states (rest versus meditation) and between time points (before versus after training) were observed. During meditation, the internal consistency in the precuneus and the temporoparietal junction increased, while the internal consistency of frontal brain regions decreased. A follow-up analysis of regional connectivity of the dorsal anterior cingulate cortex further revealed reduced connectivity with anterior insula during meditation. After meditation training, reduced resting state functional connectivity between the pregenual anterior cingulate and dorsal medical prefrontal cortex was observed. Most importantly, significantly reduced depression/anxiety scores were observed after training. Hence, these findings suggest that mindfulness meditation might be of therapeutic use by inducing plasticity related network changes altering the neuronal basis of affective disorders such as depression. PMID:26998365

  12. Mechanism of Traumatic Brain Injury at Distant Locations After Exposure to Blast Waves: Preliminary Results from Animal and Phantom Experiments.

    Science.gov (United States)

    Nakagawa, Atsuhiro; Ohtani, Kiyonobu; Goda, Keisuke; Kudo, Daisuke; Arafune, Tatsuhiko; Washio, Toshikatsu; Tominaga, Teiji

    2016-01-01

    Purpose Primary blast-induced traumatic brain injury (bTBI) is the least understood of the four phases of blast injury. Distant injury induced by the blast wave, on the opposite side from the wave entry, is not well understood. This study investigated the mechanism of distant injury in bTBI. Materials and Methods Eight 8-week-old male Sprague-Dawley rats were divided into two groups: group 1 served as the control group and did not receive any shock wave (SW) exposure; group 2 was exposed to SWs (12.5 ± 2.5 MPa). Propagation of SWs within a brain phantom was evaluated by visualization, pressure measurement, and numerical simulation. Results Intracerebral hemorrhage near the ignition site and elongation of the distant nucleus were observed, despite no apparent damage between the two locations in the animal experiment. Visualization, pressure measurement, and numerical simulation indicated the presence of complex wave dynamics accompanying a sudden increase in pressure, followed by negative pressure in the phantom experiment. Conclusion A local increase in pressure above the threshold caused by interference of reflection and rarefaction waves in the vicinity of the brain-skull surface may cause distant injury in bTBI. PMID:27165867

  13. Alien Hand, Restless Brain: Salience Network and Interhemispheric Connectivity Disruption Parallel Emergence and Extinction of Diagonistic Dyspraxia

    Science.gov (United States)

    Ridley, Ben; Beltramone, Marion; Wirsich, Jonathan; Le Troter, Arnaud; Tramoni, Eve; Aubert, Sandrine; Achard, Sophie; Ranjeva, Jean-Philippe; Guye, Maxime; Felician, Olivier

    2016-01-01

    Diagonistic dyspraxia (DD) is by far the most spectacular manifestation reported by sufferers of acute corpus callosum (CC) injury (so-called “split-brain”). In this form of alien hand syndrome, one hand acts at cross purposes with the other “against the patient’s will”. Although recent models view DD as a disorder of motor control, there is still little information regarding its neural underpinnings, due to widespread connectivity changes produced by CC insult, and the obstacle that non-volitional movements represent for task-based functional neuroimaging studies. Here, we studied patient AM, the first report of DD in patient with complete developmental CC agenesis. This unique case also offers the opportunity to study the resting-state connectomics of DD in the absence of diffuse changes subsequent to CC injury or surgery. AM developed DD following status epilepticus (SE) which resolved over a 2-year period. Whole brain functional connectivity (FC) was compared (Crawford-Howell [CH]) to 16 controls during the period of acute DD symptoms (Time 1) and after remission (Time 2). Whole brain graph theoretical models were also constructed and topological efficiency examined. At Time 1, disrupted FC was observed in inter-hemispheric and intra-hemispheric right edges, involving frontal superior and midline structures. Graph analysis indicated disruption of the efficiency of salience and right frontoparietal (FP) networks. At Time 2, after remission of diagnostic dyspraxia symptoms, FC and salience network changes had resolved. In sum, longitudinal analysis of connectivity in AM indicates that DD behaviors could result from disruption of systems that support the experience and control of volitional movements and the ability to generate appropriate behavioral responses to salient stimuli. This also raises the possibility that changes to large-scale functional architecture revealed by resting-state functional magnetic resonance imaging (fMRI) (rs-fMRI) may provide

  14. The Emerging Role of TPR-Domain Immunophilins in the Mechanism of Action of Steroid Receptors

    Directory of Open Access Journals (Sweden)

    G. I. Mazaira

    2014-11-01

    Full Text Available In the absence of ligand, some members of nuclear receptor family such as corticosteroid receptors are primarily located in the cytoplasm, and they rapidly accumulate in the nucleus upon ligand-binding. Other members of the family such as the estrogen receptor are mostly nuclear. Regardless of their primary location, these oligomeric proteins undergo a dynamic nuclear-cytoplasmic shuttling, and their transport through the cytoplasmic compartment has always been assumed to occur in a stochastic manner by simple diffusion. Although heuristic, this oversimplified model has never been demonstrated. Moreover, it has always been assumed that the first step related to receptor activation is the dissociation of the Hsp90-based heterocomplex, a process referred to as `transformation.' Nonetheless, recent experimental evidence indicates that the chaperone machinery is required for the retrotransport of the receptor throughout the cytoplasm and facilitates its active passage through the nuclear pore. Therefore, transformation is actually a nuclear event. A group of Hsp90-binding cochaperones belonging to the immunophilin family plays a cardinal role not only in the mechanism for receptor movement, but also in nuclear events leading to interactions with nuclear sites of action and the regulation of transcriptional activity. In this article we analyze the importance of molecular chaperones and TPR-domain immunophilins in the molecular mechanism of action of steroid receptors.

  15. Renewable Energy Investment in Emerging Markets: Evaluating Improvements to the Clean Development Mechanism

    Directory of Open Access Journals (Sweden)

    Amy Tang

    2014-06-01

    Full Text Available In the past, industrialized countries have invested in or financed numerous renewable energy projects in developing countries, primarily through the Clean Development Mechanism (CDM of the Kyoto Protocol. However, critics have pointed to its bureaucratic structure, problems with additionality and distorted credit prices as ill-equipped to streamline renewable energy investment. In this paper, we simulate the impact of policy on investment decisions on whether or not to invest in wind energy infrastructure in India, Brazil and China. Data from 2,578 past projects as well as literature on investor behaviour is used to inform the model structure and parameters. Our results show that the CDM acts differently in each country and reveal that while streamlining the approval process and reconsidering additionality can lead to non-trivial increase in total investment, stabilizing policy and decreasing investment risk will do the most to spur investment.

  16. Mechanism of wavelength conversion in polystyrene doped with benzoxanthene: emergence of a complex

    Science.gov (United States)

    Nakamura, Hidehito; Shirakawa, Yoshiyuki; Kitamura, Hisashi; Sato, Nobuhiro; Shinji, Osamu; Saito, Katashi; Takahashi, Sentaro

    2013-01-01

    Fluorescent guest molecules doped in polymers have been used to convert ultraviolet light into visible light for applications ranging from optical fibres to filters for the cultivation of plants. The wavelength conversion process involves the absorption of light at short wavelengths followed by fluorescence emission at a longer wavelength. However, a precise understanding of the light conversion remains unclear. Here we show light responses for a purified polystyrene base substrates doped with fluorescent benzoxanthene in concentrations varied over four orders of magnitude. The shape of the excitation spectrum for fluorescence emission changes significantly with the concentration of the benzoxanthene, indicating formation of a base substrate/fluorescent molecule complex. Furthermore, the wavelength conversion light yield increases in three stages depending on the nature of the complex. These findings identify a mechanism that will have many applications in wavelength conversion materials. PMID:23974205

  17. Emerging GaN-based HEMTs for mechanical sensing within harsh environments

    Science.gov (United States)

    Köck, Helmut; Chapin, Caitlin A.; Ostermaier, Clemens; Häberlen, Oliver; Senesky, Debbie G.

    2014-06-01

    Gallium nitride based high-electron-mobility transistors (HEMTs) have been investigated extensively as an alternative to Si-based power transistors by academia and industry over the last decade. It is well known that GaN-based HEMTs outperform Si-based technologies in terms of power density, area specific on-state resistance and switching speed. Recently, wide band-gap material systems have stirred interest regarding their use in various sensing fields ranging from chemical, mechanical, biological to optical applications due to their superior material properties. For harsh environments, wide bandgap sensor systems are deemed to be superior when compared to conventional Si-based systems. A new monolithic sensor platform based on the GaN HEMT electronic structure will enable engineers to design highly efficient propulsion systems widely applicable to the automotive, aeronautics and astronautics industrial sectors. In this paper, the advancements of GaN-based HEMTs for mechanical sensing applications are discussed. Of particular interest are multilayered heterogeneous structures where spontaneous and piezoelectric polarization between the interface results in the formation of a 2-dimensional electron gas (2DEG). Experimental results presented focus on the signal transduction under strained operating conditions in harsh environments. It is shown that a conventional AlGaN/GaN HEMT has a strong dependence of drain current under strained conditions, thus representing a promising future sensor platform. Ultimately, this work explores the sensor performance of conventional GaN HEMTs and leverages existing technological advances available in power electronics device research. The results presented have the potential to boost GaN-based sensor development through the integration of HEMT device and sensor design research.

  18. The Research of Innovation Mechanism of China's Emergency Logistics System%我国应急物流体系创新机制研究

    Institute of Scientific and Technical Information of China (English)

    刘小更

    2012-01-01

    从应急物流的内涵、特点入手,提出了应急物流体系创新机制的构建,包括应急物流信息平台、应急物流快速反应机制、应急物流政府保障机制和应急物流的反馈控制机制四大模块。只有这些创新机制的协同运作。突发事件的物资供应才能得到有效保障。%From the content and the characteristics of file emergency logistics, the article is proposed building the innovative mec, hanisms of the emergency logistics system. There are four modules in the emergency logistics system, including the information platform of emergency logistics, the rapid response mechanism of emergency logistics, government safeguards mechanism and feedback control mechanism of emergency logistics to four modules. Only co-operation of these innovative mechanisms, emergency supplies can be effectively protected.

  19. Emerging concepts of how β-amyloid proteins and pro-inflammatory cytokines might collaborate to produce an 'Alzheimer brain' (Review).

    Science.gov (United States)

    Dal Pra, Ilaria; Chiarini, Anna; Pacchiana, Raffaella; Chakravarthy, Balu; Whitfield, James F; Armato, Ubaldo

    2008-01-01

    Three steps lead to the development of full-blown sporadic or late-onset Alzheimer's disease or dementia (AD). In the young brain, amyloid β-(1-42) (Aβ 42) is a normal aggregation-prone protein product of neuronal activity that is kept at a safe low level by proteolysis in neurons and glial cells, and by expulsion across the blood-brain barrier. But clearance declines with advancing age. Step 1: Because of the normal decline with age of the Aβ 42-clearing mechanisms, toxic amyloid-derived diffusible ligands (ADDLs) made of dodecamers of the aggregation-prone Aβ 42 start accumulating. These Aβ 42 dodecamers selectively target the initially huge numbers of excitatory synapses of neurons and cause them to start slowly dropping, which increasingly impairs plasticity and sooner or later starts noticeably affecting memory formation. At a certain point, this increasing loss of synapses induces the neurons to redirect their still-expressed cell cycle proteins from post-mitotic jobs, such as maintaining synapses, to starting a cell cycle and partially or completely replicating DNA without entering mitosis. The resulting aneuploid or tetraploid neurons survive for as long as 6-12 months as quasi-functional 'undead zombies', with developing tangles of hyperphosphorylated τ protein disrupting the vital anterograde axonal transport of mitochondria and other synapse-vital components. Step 2: The hallmark AD plaques appear as Aβ 42 clearance continues to decline and the formation of Aβ 42 non-diffusible fibrils begins in the aging brain. Step 3: A terminal cytokine-driven maëlstrom begins in the aging brain when microglia, the brain's professional macrophages, are activated in and around the plaques. They produce pro-inflammatory cytokines, such as IFN-γ, IL-1β and TNF-α. One of these, IFN-γ, causes the astrocytes enwrapping the neuronal synapses to express their β-secretase (BACE1) genes and produce and release Aβ 42, which can kill the closely apposed neurons by

  20. A Battery-Less, Implantable Neuro-Electronic Interface for Studying the Mechanisms of Deep Brain Stimulation in Rat Models.

    Science.gov (United States)

    Lin, Yu-Po; Yeh, Chun-Yi; Huang, Pin-Yang; Wang, Zong-Ye; Cheng, Hsiang-Hui; Li, Yi-Ting; Chuang, Chi-Fen; Huang, Po-Chiun; Tang, Kea-Tiong; Ma, Hsi-Pin; Chang, Yen-Chung; Yeh, Shih-Rung; Chen, Hsin

    2016-02-01

    Although deep brain stimulation (DBS) has been a promising alternative for treating several neural disorders, the mechanisms underlying the DBS remain not fully understood. As rat models provide the advantage of recording and stimulating different disease-related regions simultaneously, this paper proposes a battery-less, implantable neuro-electronic interface suitable for studying DBS mechanisms with a freely-moving rat. The neuro-electronic interface mainly consists of a microsystem able to interact with eight different brain regions bi-directionally and simultaneously. To minimize the size of the implant, the microsystem receives power and transmits data through a single coil. In addition, particular attention is paid to the capability of recording neural activities right after each stimulation, so as to acquire information on how stimulations modulate neural activities. The microsystem has been fabricated with the standard 0.18 μm CMOS technology. The chip area is 7.74 mm (2) , and the microsystem is able to operate with a single supply voltage of 1 V. The wireless interface allows a maximum power of 10 mW to be transmitted together with either uplink or downlink data at a rate of 2 Mbps or 100 kbps, respectively. The input referred noise of recording amplifiers is 1.16 μVrms, and the stimulation voltage is tunable from 1.5 V to 4.5 V with 5-bit resolution. After the electrical functionality of the microsystem is tested, the capability of the microsystem to interface with rat brain is further examined and compared with conventional instruments. All experimental results are presented and discussed in this paper. PMID:25838526

  1. Is beat induction innate or learned? Probing emergent meter perception in adults and newborns using event-related brain potentials.

    Science.gov (United States)

    Honing, Henkjan; Ladinig, Olivia; Háden, Gábor P; Winkler, István

    2009-07-01

    Meter is considered an important structuring mechanism in the perception and experience of rhythm in music. Combining behavioral and electrophysiological measures, in the present study we investigate whether meter is more likely a learned phenomenon, possibly a result of musical expertise, or whether sensitivity to meter is also active in adult nonmusicians and newborn infants. The results provide evidence that meter induction is active in adult nonmusicians and that beat induction is already functional right after birth.

  2. Radiation-induced apoptosis in undifferentiated cells of the developing brain as a biological defense mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Inouye, Minioru [Nagoya Univ. (Japan). Research Inst. of Environmental Medicine; Tamaru, Masao

    1994-12-31

    Undifferentiated neural (UN) cells of the developing mammalian brain are highly sensitive to the lethal effects of ionizing radiation. Nuclear and cytoplasmic condensation, transglutaminase activation, and internucleosomal DNA cleavage reveal radiation-induced cell death in the ventricular zone of the cerebral mantle and external granular layer of the cerebellum to be due to apoptosis. A statistically significant increase of cell mortality can be induced by 0.03 Gy X-irradiation, and the mortality increases linearly with increasing doses. It is not changed by split doses, probably because of the very slow repair of cellular damage and a lack of adaptive response. Although extensive apoptosis in the UN cell population results in microcephaly and mental retardation, it possesses the ability to recover from a considerable cell loss and to form the normal structure of the central nervous system. The number of cell deaths needed to induce tissue adnormalities in the adult murine brain rises in the range of 15-25% of the germinal cell population; with the threshold doses at about 0.3 Gy for cerebral anomalies and 1 Gy for cerebellar abnormalities. Threshold level is similarly suggested in prenatally exposed A-bomb survivors. High radiosensitivity of UN cells is assumed to be a manifestation of the ability of the cell to commit suicide when injured. Repeated replication of DNA and extensive gene expression are required in future proliferation and differentiation. Once an abnormality in DNA was induced and fixed in the UN cell, it would be greatly amplified and prove a danger in producing malformations and tumors. These cells would thus commit suicide for the benefit of the individual to eliminate their acquired genetic abnormalities rather than make DNA repair. UN cells in the developing brain are highly radiosensitive and readily involved in apoptosis. Paradoxically, however, this may be to protect individuals against teratogenesis and tumorigenesis. (J.P.N.).

  3. Unexpected events induce motor slowing via a brain mechanism for action-stopping with global suppressive effects.

    Science.gov (United States)

    Wessel, Jan R; Aron, Adam R

    2013-11-20

    When an unexpected event occurs in everyday life (e.g., a car honking), one experiences a slowing down of ongoing action (e.g., of walking into the street). Motor slowing following unexpected events is a ubiquitous phenomenon, both in laboratory experiments as well as such everyday situations, yet the underlying mechanism is unknown. We hypothesized that unexpected events recruit the same inhibition network in the brain as does complete cancellation of an action (i.e., action-stopping). Using electroencephalography and independent component analysis in humans, we show that a brain signature of successful outright action-stopping also exhibits activity following unexpected events, and more so in blocks with greater motor slowing. Further, using transcranial magnetic stimulation to measure corticospinal excitability, we show that an unexpected event has a global motor suppressive effect, just like outright action-stopping. Thus, unexpected events recruit a common mechanism with outright action-stopping, moreover with global suppressive effects. These findings imply that we can now leverage the considerable extant knowledge of the neural architecture and functional properties of the stopping system to better understand the processing of unexpected events, including perhaps how they induce distraction via global suppression.

  4. Molecular mechanisms underlying the regulation of brain-derived neurotrophic factor (BDNF) translation in dendrites

    OpenAIRE

    Pinheiro, Vera Lúcia Margarido

    2010-01-01

    A especificidade espacial e temporal subjacente à diversidade de processos de plasticidade sináptica que ocorrem no sistema nervoso central está profundamente relacionada com a disponibilidade da proteína brain-derived neurotrophic factor (BDNF) em domínios sub-celulares distintos, especialmente na área pós-sináptica. Contudo, os mecanismos moleculares que regulam a síntese proteica de BDNF nas dendrites estão ainda por desvendar. Assim, o principal objectivo deste trabalho foi...

  5. The Coherent Heart Heart–Brain Interactions, Psychophysiological Coherence, and the Emergence of System-Wide Order

    Directory of Open Access Journals (Sweden)

    Raymond Trevor Bradley

    2009-12-01

    Full Text Available This article presents theory and research on the scientific study of emotion thatemphasizes the importance of coherence as an optimal psychophysiological state. Adynamic systems view of the interrelations between psychological, cognitive andemotional systems and neural communication networks in the human organism providesa foundation for the view presented. These communication networks are examined froman information processing perspective and reveal a fundamental order in heart-braininteractions and a harmonious synchronization of physiological systems associated withpositive emotions. The concept of coherence is drawn on to understand optimalfunctioning which is naturally reflected in the heart’s rhythmic patterns. Research ispresented identifying various psychophysiological states linked to these patterns, withneurocardiological coherence emerging as having significant impacts on well being.These include psychophysiological as well as improved cognitive performance. Fromthis, the central role of the heart is explored in terms of biochemical, biophysical andenergetic interactions. Appendices provide further details and research on;psychophysiological functioning, reference previous research in this area, details onresearch linking coherence with optimal cognitive performance, heart brainsynchronization and the energetic signature of the various psychophysiological modes.

  6. New mechanized system for circle spraying of oil palms seedling emergence

    Directory of Open Access Journals (Sweden)

    Darius El Pebrian

    2012-04-01

    Full Text Available A new machine system has been designed, developed and evaluated for extensive circle spraying of oil palms (Elaeis guineensis Jacq. in an effort to overcome the inefficient spraying problem with the conventional spraying system. The machine system consists of a four-wheeled drive 4WD prime mover with front mounted machine attachments for the circle spraying operation. The configuration of the circle spraying attachment consists of a hexagonal curved spray boom, lifting arm, opening-tilting mechanism unit, storage tank, spray pump, solid cone nozzles, and associate hydraulic system. Field performance tests on the machine system showed an average effective field capacity of 7.89 ha per man per day and when compared to the earlier reported effective field capacity of the walking spray-operated equipment using Serena LT16 knapsack sprayer; a difference of 1.97 time for circle spraying of mature palms grove. Reduction in the human energy expenditure of 101.28 kJ man-1 h-1 or 10.68 % but an increase in the spraying cost of 1.53 USD ha-1 or 24.9 % were obtained with the machine system against the walking spraying-operated equipment using Serena LT16 knapsack sprayer. Justification for machine system to be cost effective could be satisfied if the present effective field capacity is increased to 1.263 time with good skilled operator or if the current R&D cost is reduced to 0.41 time. This is because the improved field capacity of new machine system could not rationalize its current R&D cost. Admittedly, the machine system has great potential to overcome the limitations with the current employed machine/equipment in the circle spraying operation of oil palms in the plantation.

  7. B Vitamins and the Brain: Mechanisms, Dose and Efficacy—A Review

    Directory of Open Access Journals (Sweden)

    David O. Kennedy

    2016-01-01

    Full Text Available The B-vitamins comprise a group of eight water soluble vitamins that perform essential, closely inter-related roles in cellular functioning, acting as co-enzymes in a vast array of catabolic and anabolic enzymatic reactions. Their collective effects are particularly prevalent to numerous aspects of brain function, including energy production, DNA/RNA synthesis/repair, genomic and non-genomic methylation, and the synthesis of numerous neurochemicals and signaling molecules. However, human epidemiological and controlled trial investigations, and the resultant scientific commentary, have focused almost exclusively on the small sub-set of vitamins (B9/B12/B6 that are the most prominent (but not the exclusive B-vitamins involved in homocysteine metabolism. Scant regard has been paid to the other B vitamins. This review describes the closely inter-related functions of the eight B-vitamins and marshals evidence suggesting that adequate levels of all members of this group of micronutrients are essential for optimal physiological and neurological functioning. Furthermore, evidence from human research clearly shows both that a significant proportion of the populations of developed countries suffer from deficiencies or insufficiencies in one or more of this group of vitamins, and that, in the absence of an optimal diet, administration of the entire B-vitamin group, rather than a small sub-set, at doses greatly in excess of the current governmental recommendations, would be a rational approach for preserving brain health.

  8. Blood-brain barrier permeability mechanisms in view of quantitative structure-activity relationships (QSAR).

    Science.gov (United States)

    Bujak, Renata; Struck-Lewicka, Wiktoria; Kaliszan, Michał; Kaliszan, Roman; Markuszewski, Michał J

    2015-04-10

    The goal of the present paper was to develop a quantitative structure-activity relationship (QSAR) method using a simple statistical approach, such as multiple linear regression (MLR) for predicting the blood-brain barrier (BBB) permeability of chemical compounds. The "best" MLR models, comprised logP and either molecular mass (M) or isolated atomic energy (E(isol)), tested on a structurally diverse set of 66 compounds, is characterized the by correlation coefficients (R) around 0.8. The obtained models were validated using leave-one-out (LOO) cross-validation technique and the correlation coefficient of leave-one-out- R(LOO)(2) (Q(2)) was at least 0.6. Analysis of a case from legal medicine demonstrated informative value of our QSAR model. To best authors' knowledge the present study is a first application of the developed QSAR models of BBB permeability to case from the legal medicine. Our data indicate that molecular energy-related descriptors, in combination with the well-known descriptors of lipophilicity may have a supportive value in predicting blood-brain distribution, which is of utmost importance in drug development and toxicological studies.

  9. Short-term retrospective versus prospective memory processing as emergent properties of the mind and brain: human fMRI evidence.

    Science.gov (United States)

    Mok, L W

    2012-12-13

    demonstrated that short-term retrospection and prospection may emerge without necessarily relying on working memory-specific brain networks. Furthermore, attention may not necessarily be recruited to realize working memory. When cognitive processes are spontaneously experienced, they may be facilitated by the default brain network.

  10. Neurotransmitter mechanisms in the nucleus accumbens septi and related regions in the rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Walaas, I.

    1981-06-30

    The investigation compares the localization of different transmitter candidates, particularly the amino acide ..gamma..-aminobutyrate (GABA) and glutamate (GLU), in limbic and basal ganglia regions in the rat brain. In particular, the characteristics of nucleus accumbens septi have been studied in some detail. GABA neurons have been found in nucleus accumbens, and GABA projections from this nucleus have been identified in restricted basal forebrain and mesencephalic regions. GLU projections from the neo- or allocortex have been found to terminate in nucleus accumbens and other forebrain and hypothalamic nuclei. Neurotransmitters in local neurons have been identified in the hippocampus, nucleus accumbens, septum and caudatoputamen by means of local kainic acid injections, while neurons in the mediobasal hypothalamus have been studied after systemic treatment of newborn animals with monosodium glutamate. The results are discussed as a basis for a better understanding of limbic-basal ganglia interactions.

  11. Mechanisms of oxidative stress in brain ischemia injury%氧化应激在脑缺血损伤中的作用机制

    Institute of Scientific and Technical Information of China (English)

    赵丹洋; 吴伟康

    2004-01-01

    Oxidative stress has been implicated in brain injury after ischemia, which is a complex cascade. These oxidants produced by oxidative stress are directly involved in oxidative damage with cellular macromolecules such as lipids, proteins and nucleic acids, which lead to cell death. Oxidants are also mediators in signaling involving mitochondria pathway, DNA repair enzymes, and transcription factor that may lead to apoptosis after cerebral ischemia. Antioxidangt enzymes (such as superoxide dismutase,etc) provide useful tools in dissecting the events involving oxidative stress in signaling and damage in ischemic brain injury. This review focuses on the mechanisms of oxidative stress during brain ischemia.

  12. Assessing Quantitative Changes in Intrinsic Thalamic Networks in Blast and Nonblast Mild Traumatic Brain Injury: Implications for Mechanisms of Injury.

    Science.gov (United States)

    Nathan, Dominic E; Bellgowan, Julie F; Oakes, Terrence R; French, Louis M; Nadar, Sreenivasan R; Sham, Elyssa B; Liu, Wei; Riedy, Gerard

    2016-06-01

    In the global war on terror, the increased use of improvised explosive devices has resulted in increased incidence of blast-related mild traumatic brain injury (mTBI). Diagnosing mTBI is both challenging and controversial due to heterogeneity of injury location, trauma intensity, transient symptoms, and absence of focal biomarkers on standard clinical imaging modalities. The goal of this study is to identify a brain biomarker that is sensitive to mTBI injury. Research suggests the thalamus may be sensitive to changes induced by mTBI. A significant number of connections to and from various brain regions converge at the thalamus. In addition, the thalamus is involved in information processing, integration, and regulation of specific behaviors and mood. In this study, changes in task-free thalamic networks as quantified by graph theory measures in mTBI blast (N = 186), mTBI nonblast (N = 80), and controls (N = 21) were compared. Results show that the blast mTBI group had significant hyper-connectivity compared with the controls and nonblast mTBI group. However, after controlling for post-traumatic stress symptoms (PTSS), the blast mTBI group was not different from the controls, but the nonblast mTBI group showed significant hypo-connectivity. The results suggest that there are differences in the mechanisms of injury related to mTBI as reflected in the architecture of the thalamic networks. However, the effect of PTSS and its relationship to mTBI is difficult to distinguish and warrants more research.

  13. The emerging role of Notch pathway in ageing: Focus on the related mechanisms in age-related diseases.

    Science.gov (United States)

    Balistreri, Carmela Rita; Madonna, Rosalinda; Melino, Gerry; Caruso, Calogero

    2016-08-01

    Notch signaling is an evolutionarily conserved pathway, which is fundamental for the development of all tissues, organs and systems of human body. Recently, a considerable and still growing number of studies have highlighted the contribution of Notch signaling in various pathological processes of the adult life, such as age-related diseases. In particular, the Notch pathway has emerged as major player in the maintenance of tissue specific homeostasis, through the control of proliferation, migration, phenotypes and functions of tissue cells, as well as in the cross-talk between inflammatory cells and the innate immune system, and in onset of inflammatory age-related diseases. However, until now there is a confounding evidence about the related mechanisms. Here, we discuss mechanisms through which Notch signaling acts in a very complex network of pathways, where it seems to have the crucial role of hub. Thus, we stress the possibility to use Notch pathway, the related molecules and pathways constituting this network, both as innovative (predictive, diagnostic and prognostic) biomarkers and targets for personalised treatments for age-related diseases. PMID:27328278

  14. Emerging systems biology approaches in nanotoxicology: Towards a mechanism-based understanding of nanomaterial hazard and risk.

    Science.gov (United States)

    Costa, Pedro M; Fadeel, Bengt

    2016-05-15

    Engineered nanomaterials are being developed for a variety of technological applications. However, the increasing use of nanomaterials in society has led to concerns about their potential adverse effects on human health and the environment. During the first decade of nanotoxicological research, the realization has emerged that effective risk assessment of the multitudes of new nanomaterials would benefit from a comprehensive understanding of their toxicological mechanisms, which is difficult to achieve with traditional, low-throughput, single end-point oriented approaches. Therefore, systems biology approaches are being progressively applied within the nano(eco)toxicological sciences. This novel paradigm implies that the study of biological systems should be integrative resulting in quantitative and predictive models of nanomaterial behaviour in a biological system. To this end, global 'omics' approaches with which to assess changes in genes, proteins, metabolites, etc. are deployed allowing for computational modelling of the biological effects of nanomaterials. Here, we highlight omics and systems biology studies in nanotoxicology, aiming towards the implementation of a systems nanotoxicology and mechanism-based risk assessment of nanomaterials.

  15. Emerging systems biology approaches in nanotoxicology: Towards a mechanism-based understanding of nanomaterial hazard and risk.

    Science.gov (United States)

    Costa, Pedro M; Fadeel, Bengt

    2016-05-15

    Engineered nanomaterials are being developed for a variety of technological applications. However, the increasing use of nanomaterials in society has led to concerns about their potential adverse effects on human health and the environment. During the first decade of nanotoxicological research, the realization has emerged that effective risk assessment of the multitudes of new nanomaterials would benefit from a comprehensive understanding of their toxicological mechanisms, which is difficult to achieve with traditional, low-throughput, single end-point oriented approaches. Therefore, systems biology approaches are being progressively applied within the nano(eco)toxicological sciences. This novel paradigm implies that the study of biological systems should be integrative resulting in quantitative and predictive models of nanomaterial behaviour in a biological system. To this end, global 'omics' approaches with which to assess changes in genes, proteins, metabolites, etc. are deployed allowing for computational modelling of the biological effects of nanomaterials. Here, we highlight omics and systems biology studies in nanotoxicology, aiming towards the implementation of a systems nanotoxicology and mechanism-based risk assessment of nanomaterials. PMID:26721310

  16. 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.

  17. Modeling oscillatory dynamics in brain microcircuits as a way to help uncover neurological disease mechanisms: A proposal

    Science.gov (United States)

    Skinner, F. K.; Ferguson, K. A.

    2013-12-01

    There is an undisputed need and requirement for theoretical and computational studies in Neuroscience today. Furthermore, it is clear that oscillatory dynamical output from brain networks is representative of various behavioural states, and it is becoming clear that one could consider these outputs as measures of normal and pathological brain states. Although mathematical modeling of oscillatory dynamics in the context of neurological disease exists, it is a highly challenging endeavour because of the many levels of organization in the nervous system. This challenge is coupled with the increasing knowledge of cellular specificity and network dysfunction that is associated with disease. Recently, whole hippocampus in vitro preparations from control animals have been shown to spontaneously express oscillatory activities. In addition, when using preparations derived from animal models of disease, these activities show particular alterations. These preparations present an opportunity to address challenges involved with using models to gain insight because of easier access to simultaneous cellular and network measurements, and pharmacological modulations. We propose that by developing and using models with direct links to experiment at multiple levels, which at least include cellular and microcircuit, a cycling can be set up and used to help us determine critical mechanisms underlying neurological disease. We illustrate our proposal using our previously developed inhibitory network models in the context of these whole hippocampus preparations and show the importance of having direct links at multiple levels.

  18. Modeling oscillatory dynamics in brain microcircuits as a way to help uncover neurological disease mechanisms: A proposal

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, F. K. [Toronto Western Research Institute, University Health Network, Krembil Discovery Tower, Toronto Western Hospital, 60 Leonard Street, 7th floor, 7KD411, Toronto, Ontario M5T 2S8 (Canada); Department of Medicine (Neurology), University of Toronto, 200 Elizabeth Street, Toronto, Ontario M5G 2C4 (Canada); Department of Physiology, University of Toronto Medical Sciences Building, 3rd Floor, 1 King' s College Circle, Toronto, Ontario M5S 1A8 (Canada); Ferguson, K. A. [Toronto Western Research Institute, University Health Network, Krembil Discovery Tower, Toronto Western Hospital, 60 Leonard Street, 7th floor, 7KD411, Toronto, Ontario M5T 2S8 (Canada); Department of Physiology, University of Toronto Medical Sciences Building, 3rd Floor, 1 King' s College Circle, Toronto, Ontario M5S 1A8 (Canada)

    2013-12-15

    There is an undisputed need and requirement for theoretical and computational studies in Neuroscience today. Furthermore, it is clear that oscillatory dynamical output from brain networks is representative of various behavioural states, and it is becoming clear that one could consider these outputs as measures of normal and pathological brain states. Although mathematical modeling of oscillatory dynamics in the context of neurological disease exists, it is a highly challenging endeavour because of the many levels of organization in the nervous system. This challenge is coupled with the increasing knowledge of cellular specificity and network dysfunction that is associated with disease. Recently, whole hippocampus in vitro preparations from control animals have been shown to spontaneously express oscillatory activities. In addition, when using preparations derived from animal models of disease, these activities show particular alterations. These preparations present an opportunity to address challenges involved with using models to gain insight because of easier access to simultaneous cellular and network measurements, and pharmacological modulations. We propose that by developing and using models with direct links to experiment at multiple levels, which at least include cellular and microcircuit, a cycling can be set up and used to help us determine critical mechanisms underlying neurological disease. We illustrate our proposal using our previously developed inhibitory network models in the context of these whole hippocampus preparations and show the importance of having direct links at multiple levels.

  19. Does harmonization of payment mechanisms enhance equitable health outcomes in delivery of emergency medical services in Thailand?

    Science.gov (United States)

    Suriyawongpaisal, Paibul; Aekplakorn, Wichai; Tansirisithikul, Rassamee

    2015-12-01

    There are different reimbursement rates by the various insurance schemes in Thailand, which include the Universal Coverage scheme (UCS), civil servant medical benefit scheme (CSMBS) and social security scheme (SSS). Hence, there are concerns about inequitable care standards. Harmonization of the rates of emergency medical services has been started since April 2012. This study analyzed the impact of harmonization on clinical outcomes in private hospitals. Analysis of 22 900 records of the dataset accrued from April 2012 to June 2013 using multiple logistic modelling revealed that beneficiaries under UCS were the worst off [Odds ratio 2.56 95% of confidence interval: 2.35 to 2.80 for non-trauma and 2.19 (1.59-3.0) for trauma, corresponding to 21.26 and 25.09% of bad outcomes, respectively] in terms of not improved or dead outcomes at discharge compared with those under the CSMBS (8.45 and 12.78%, respectively) controlling for age, sex, hospital location, triage priority code, length of stays and adjusted Relative weight (RW) score. Using propensity score, matching analysis found the outcome rates of not improved including dead were highest in UCS 26.27% for trauma and 21.26% for non-trauma patients. Payment mechanism alone is inadequate to ensure equitable distribution of health outcomes in provision of emergency medical care by private providers in urban settings across the country. A secondary finding was that patients accessing hospital services directly showed better improvement or lower in-hospital mortality compared with access through formal pre-hospital means (P < 0.001). Plausible explanations have been discussed with policy implications and recommendations for further studies. PMID:25797471

  20. Brain dynamic mechanisms on the visual attention scale with Chinese characters cues

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The temporal dynamics in brain evoked by the scale of visual attention with the cues of Chinese characters were studied by recording event-related potentials (ERPs). With the fixed orientation of visual attention, 14 healthy young participants performed a search task in which the search array was preceded by Chinese characters cues, "大, 中, 小" (large, medium, small). 128 channels scalp ERPs were recorded to study the role of visual attention scale played in the visual spatial attention. The results showed that there was no significant difference in the ERP components evoked by the three Chinese characters cues except the inferoposterior N2 latency. The targets evoked P2, N2 amplitudes and latency have significant differences with the different cues of large, middle and small, while P1 and N1 components had no significant difference. The results suggested that the processing of scale of visual attention was mainly concerned with P2, N2 components, while the P1, N1 components were mainly related with the processing of visual orientation information.

  1. Brain-derived neurotrophic factor enhances calcium regulatory mechanisms in human airway smooth muscle.

    Directory of Open Access Journals (Sweden)

    Amard J Abcejo

    Full Text Available Neurotrophins (NTs, which play an integral role in neuronal development and function, have been found in non-neuronal tissue (including lung, but their role is still under investigation. Recent reports show that NTs such as brain-derived neurotrophic factor (BDNF as well as NT receptors are expressed in human airway smooth muscle (ASM. However, their function is still under investigation. We hypothesized that NTs regulate ASM intracellular Ca(2+ ([Ca(2+](i by altered expression of Ca(2+ regulatory proteins. Human ASM cells isolated from lung samples incidental to patient surgery were incubated for 24 h (overnight in medium (control or 1 nM BDNF in the presence vs. absence of inhibitors of signaling cascades (MAP kinases; PI3/Akt; NFκB. Measurement of [Ca(2+](i responses to acetylcholine (ACh and histamine using the Ca(2+ indicator fluo-4 showed significantly greater responses following BDNF exposure: effects that were blunted by pathway inhibitors. Western analysis of whole cell lysates showed significantly higher expression of CD38, Orai1, STIM1, IP(3 and RyR receptors, and SERCA following BDNF exposure, effects inhibited by inhibitors of the above cascades. The functional significance of BDNF effects were verified by siRNA or pharmacological inhibition of proteins that were altered by this NT. Overall, these data demonstrate that NTs activate signaling pathways in human ASM that lead to enhanced [Ca(2+](i responses via increased regulatory protein expression, thus enhancing airway contractility.

  2. Brain mechanisms of persuasion: how ‘expert power’ modulates memory and attitudes

    Science.gov (United States)

    Smidts, Ale; Fernández, Guillén

    2008-01-01

    Human behaviour is affected by various forms of persuasion. The general persuasive effect of high expertise of the communicator, often referred to as ’expert power’, is well documented. We found that a single exposure to a combination of an expert and an object leads to a long-lasting positive effect on memory for and attitude towards the object. Using functional magnetic resonance imaging, we probed the neural processes predicting these behavioural effects. Expert context was associated with distributed left-lateralized brain activity in prefrontal and temporal cortices related to active semantic elaboration. Furthermore, experts enhanced subsequent memory effects in the medial temporal lobe (i.e. in hippocampus and parahippocampal gyrus) involved in memory formation. Experts also affected subsequent attitude effects in the caudate nucleus involved in trustful behaviour, reward processing and learning. These results may suggest that the persuasive effect of experts is mediated by modulation of caudate activity resulting in a re-evaluation of the object in terms of its perceived value. Results extend our view of the functional role of the dorsal striatum in social interaction and enable us to make the first steps toward a neuroscientific model of persuasion. PMID:19015077

  3. Speech and music shape the listening brain: Evidence for shared domain-general mechanisms

    NARCIS (Netherlands)

    Asaridou, S.S.; McQueen, J.M.

    2013-01-01

    Are there bi-directional influences between speech perception and music perception? An answer to this question is essential for understanding the extent to which the speech and music that we hear are processed by domain-general auditory processes and/or by distinct neural auditory mechanisms. This r

  4. The major brain endocannabinoid 2-AG controls neuropathic pain and mechanical hyperalgesia in patients with neuromyelitis optica.

    Directory of Open Access Journals (Sweden)

    Hannah L Pellkofer

    in patients with NMO. The degree of mechanical hyperalgesia reflecting central sensitization of nociceptive pathways seems to be controlled by the major brain endocannabinoid 2-AG.

  5. Bio-Mechanical Model of the Brain for a Per-Operative Image-Guided Neuronavigator Compensating for "Brain-Shift" Deformations

    CERN Document Server

    Bucki, Marek; Payan, Yohan

    2007-01-01

    In this paper we present a methodology to address the problem of brain tissue deformation referred to as 'brain-shift'. This deformation occurs throughout a neurosurgery intervention and strongly alters the accuracy of the neuronavigation systems used to date in clinical routine which rely solely on pre-operative patient imaging to locate the surgical target, such as a tumour or a functional area. After a general description of the framework of our intra-operative image-guided system, we describe a procedure to generate patient specific finite element meshes of the brain and propose a biomechanical model which can take into account tissue deformations and surgical procedures that modify the brain structure, like tumour or tissue resection.

  6. On the mechanical characterization and modeling of polymer gel brain substitute under dynamic rotational loading.

    Science.gov (United States)

    Fontenier, B; Hault-Dubrulle, A; Drazetic, P; Fontaine, C; Naceur, H

    2016-10-01

    The use of highly sensitive soft materials has become increasingly apparent in the last few years in numerous industrial fields, due to their viscous and damping nature. Unfortunately these materials remain difficult to characterize using conventional techniques, mainly because of the very low internal forces supported by these materials especially under high strain-rates of deformation. The aim of this work is to investigate the dynamic response of a polymer gel brain analog material under specific rotational-impact experiments. The selected polymer gel commercially known as Sylgard 527 has been studied using a specific procedure for its experimental characterization and numerical modeling. At first an indentation experiment was conducted at several loading rates to study the strain rate sensitivity of the Sylgard 527 gel. During the unloading several relaxation tests were performed after indentation, to assess the viscous behavior of the material. A specific numerical procedure based on moving least square approximation and response surface method was then performed to determine adequate robust material parameters of the Sylgard 527 gel. A sensitivity analysis was assessed to confirm the robustness of the obtained material parameters. For the validation of the obtained material model, a second experiment was conducted using a dynamic rotational loading apparatus. It consists of a metallic cylindrical cup filled with the polymer gel and subjected to an eccentric transient rotational impact. Complete kinematics of the cup and the large strains induced in the Sylgard 527 gel, have been recorded at several patterns by means of optical measurement. The whole apparatus was modeled by the Finite Element Method using explicit dynamic time integration available within Ls-dyna(®) software. Comparison between the physical and the numerical models of the Sylgard 527 gel behavior under rotational choc shows excellent agreements.

  7. Soluble Epoxide Hydrolase Inhibition: Targeting Multiple Mechanisms of Ischemic Brain Injury with a Single Agent

    OpenAIRE

    Iliff, Jeffrey J.; Alkayed, Nabil J.

    2009-01-01

    Soluble epoxide hydrolase (sEH) is a key enzyme in the metabolic conversion and degradation of P450 eicosanoids called epoxyeicosatrienoic acids (EETs). Genetic variations in the sEH gene, designated EPHX2, are associated with ischemic stroke risk. In experimental studies, sEH inhibition and gene deletion reduce infarct size after focal cerebral ischemia in mice. Although the precise mechanism of protection afforded by sEH inhibition remains under investigation, EETs exhibit a wide array of p...

  8. 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...

  9. Speech and music shape the listening brain: evidence for shared domain-general mechanisms

    OpenAIRE

    Salomi S Asaridou; McQueen, James M.

    2013-01-01

    Are there bi-directional influences between speech perception and music perception? An answer to this question is essential for understanding the extent to which the speech and music that we hear are processed by domain-general auditory processes and/or by distinct neural auditory mechanisms. This review summarizes a large body of behavioral and neuroscientific findings which suggest that the musical experience of trained musicians does modulate speech processing, and a sparser set of data, l...

  10. Nucleobases bind to and stabilize aggregates of a prebiotic amphiphile, providing a viable mechanism for the emergence of protocells.

    Science.gov (United States)

    Black, Roy A; Blosser, Matthew C; Stottrup, Benjamin L; Tavakley, Ravi; Deamer, David W; Keller, Sarah L

    2013-08-13

    Primordial cells presumably combined RNAs, which functioned as catalysts and carriers of genetic information, with an encapsulating membrane of aggregated amphiphilic molecules. Major questions regarding this hypothesis include how the four bases and the sugar in RNA were selected from a mixture of prebiotic compounds and colocalized with such membranes, and how the membranes were stabilized against flocculation in salt water. To address these questions, we explored the possibility that aggregates of decanoic acid, a prebiotic amphiphile, interact with the bases and sugar found in RNA. We found that these bases, as well as some but not all related bases, bind to decanoic acid aggregates. Moreover, both the bases and ribose inhibit flocculation of decanoic acid by salt. The extent of inhibition by the bases correlates with the extent of their binding, and ribose inhibits to a greater extent than three similar sugars. Finally, the stabilizing effects of a base and ribose are additive. Thus, aggregates of a prebiotic amphiphile bind certain heterocyclic bases and sugars, including those found in RNA, and this binding stabilizes the aggregates against salt. These mutually reinforcing mechanisms might have driven the emergence of protocells. PMID:23901105

  11. Individual Differences in Working Memory, Nonverbal IQ, and Mathematics Achievement and Brain Mechanisms Associated with Symbolic and Nonsymbolic Number Processing

    Science.gov (United States)

    Gullick, Margaret M.; Sprute, Lisa A.; Temple, Elise

    2011-01-01

    Individual differences in mathematics performance may stem from domain-general factors like working memory and intelligence. Parietal and frontal brain areas have been implicated in number processing, but the influence of such cognitive factors on brain activity during mathematics processing is not known. The relationship between brain mechanisms…

  12. The changing brain--insights into the mechanisms of neural and behavioral adaptation to the environment

    DEFF Research Database (Denmark)

    Bergersen, L H; Bramham, C R; Hugdahl, K;

    2013-01-01

    in the vomero-nasal organ can switch off male-specific and switch on female-specific innate behavior of mice in response to environmental stimulation (Dulac). Innate behaviors can be stably transmitted from parent to offspring through generations even when those behaviors cannot be expressed, as illustrated...... of the Symposium presentations was the mechanisms by which animals adapt to their environment. The symposium speakers--Michael Greenberg, Erin Schuman, Chiara Cirelli, Michael Meaney, Catherine Dulac, Hopi Hoekstra, and Stanislas Dehaene--covered topics ranging from the molecular and cellular levels to the systems...

  13. Driving pressure during assisted mechanical ventilation: Is it controlled by patient brain?

    Science.gov (United States)

    Georgopoulos, Dimitris; Xirouchaki, Nectaria; Tzanakis, Nikolaos; Younes, Magdy

    2016-07-01

    Tidal volume (VT) is the controlled variable during passive mechanical ventilation (CMV) in order to avoid ventilator-induced-lung-injury. However, recent data indicate that the driving pressure [ΔP; VT to respiratory system compliance (Crs) ratio] is the parameter that best stratifies the risk of death. In order to study which variable (VT or ΔP) is controlled by critically ill patients, 108 previously studied patients were assigned to receive PAV+ (a mode that estimates Crs and permits the patients to select their own breathing pattern) after CMV, were re-analyzed. When patients were switched from CMV to PAV+ they controlled ΔP without constraining VT to narrow limits. VT was increased when the resumption of spontaneous breathing was associated with an increase in Crs. When ΔP was high during CMV, the patients (n=12) decreased it in 58 out of 67 measurements. We conclude that critically ill patients control the driving pressure by sizing the tidal volume to individual respiratory system compliance using appropriate feedback mechanisms aimed at limiting the degree of lung stress.

  14. Investigations of oxidative stress effects and their mechanisms in rat brain after systemic administration of ceria engineered nanomaterials

    Science.gov (United States)

    Hardas, Sarita S.

    Advancing applications of engineered nanomaterials (ENM) in various fields create the opportunity for intended (e.g. drug and gene delivery) or unintended (e.g. occupational and environmental) exposure to ENM. However, the knowledge of ENM-toxicity is lagging behind their application development. Understanding the ENM hazard can help us to avoid potential human health problems associated with ENM applications as well as to increase their public acceptance. Ceria (cerium [Ce] oxide) ENM have many current and potential commercial applications. Beyond the traditional use of ceria as an abrasive, the scope of ceria ENM applications now extends into fuel cell manufacturing, diesel fuel additives and for therapeutic intervention as a putative antioxidant. However, the biological effects of ceria ENM exposure have yet to be fully defined. Both pro-and anti-oxidative effects of ceria ENM exposure are repeatedly reported in literature. EPA, NIEHS and OECD organizations have nominated ceria for its toxicological evaluation. All these together gave us the impetus to examine the oxidative stress effects of ceria ENM after systemic administration. Induction of oxidative stress is one of the primary mechanisms of ENM toxicity. Oxidative stress plays an important role in maintaining the redox homeostasis in the biological system. Increased oxidative stress, due to depletion of antioxidant enzymes or molecules and / or due to increased production of reactive oxygen (ROS) or nitrogen (RNS) species may lead to protein oxidation, lipid peroxidation and/or DNA damage. Increased protein oxidation or lipid peroxidation together with antioxidant protein levels and activity can serve as markers of oxidative stress. To investigate the oxidative stress effects and the mechanisms of ceria-ENM toxicity, fully characterized ceria ENM of different sizes (˜ 5nm, 15nm, 30nm, 55nm and nanorods) were systematically injected into rats intravenously in separate experiments. Three brain regions

  15. Mechanisms of extracellular signal-regulated kinase/cAMP response element-binding protein/brain-derived neurotrophic factor signaltransduction pathway in depressive disorder

    Institute of Scientific and Technical Information of China (English)

    Hongyan Wang; Yingquan Zhang; Mingqi Qiao

    2013-01-01

    The extracellular signal-regulated kinase/cAMP response element-binding protein/brain-derived neurotrophic factor signal transduction pathway plays an important role in the mechanism of action of antidepressant drugs and has dominated recent studies on the pathogenesis of depression. In the present review we summarize the known roles of extracellular signal-regulated kinase, cAMP response element-binding protein and brain-derived neurotrophic factor in the pathogenesis of depression and in the mechanism of action of antidepressant medicines. The extracellular signal-regulated kinase/cAMP response element-binding protein/brain-derived neurotrophic factor pathway has potential to be used as a biological index to help diagnose depression, and as such it is considered as an important new target in the treatment of depression.

  16. Bifurcation mechanisms of regular and chaotic network signaling in brain astrocytes

    Science.gov (United States)

    Matrosov, V. V.; Kazantsev, V. B.

    2011-06-01

    Bifurcation mechanisms underlying calcium oscillations in the network of astrocytes are investigated. Network model includes the dynamics of intracellular calcium concentration and intercellular diffusion of inositol 1,4,5-trisphosphate through gap junctions. Bifurcation analysis of underlying nonlinear dynamical system is presented. Parameter regions and principle bifurcation boundaries have been delineated and described. We show how variations of the diffusion rate can lead to generation of network calcium oscillations in originally nonoscillating cells. Different scenarios of regular activity and its transitions to chaotic dynamics have been obtained. Then, the bifurcations have been associated with statistical characteristics of calcium signals showing that different bifurcation scenarios yield qualitative changes in experimentally measurable quantities of the astrocyte activity, e.g., statistics of calcium spikes.

  17. The biological significance of brain barrier mechanisms: help or hindrance in drug delivery to the central nervous system? [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Norman R. Saunders

    2016-03-01

    Full Text Available Barrier mechanisms in the brain are important for its normal functioning and development. Stability of the brain’s internal environment, particularly with respect to its ionic composition, is a prerequisite for the fundamental basis of its function, namely transmission of nerve impulses. In addition, the appropriate and controlled supply of a wide range of nutrients such as glucose, amino acids, monocarboxylates, and vitamins is also essential for normal development and function. These are all cellular functions across the interfaces that separate the brain from the rest of the internal environment of the body. An essential morphological component of all but one of the barriers is the presence of specialized intercellular tight junctions between the cells comprising the interface: endothelial cells in the blood-brain barrier itself, cells of the arachnoid membrane, choroid plexus epithelial cells, and tanycytes (specialized glial cells in the circumventricular organs. In the ependyma lining the cerebral ventricles in the adult brain, the cells are joined by gap junctions, which are not restrictive for intercellular movement of molecules. But in the developing brain, the forerunners of these cells form the neuroepithelium, which restricts exchange of all but the smallest molecules between cerebrospinal fluid and brain interstitial fluid because of the presence of strap junctions between the cells. The intercellular junctions in all these interfaces are the physical basis for their barrier properties. In the blood-brain barrier proper, this is combined with a paucity of vesicular transport that is a characteristic of other vascular beds. Without such a diffusional restrain, the cellular transport mechanisms in the barrier interfaces would be ineffective. Superimposed on these physical structures are physiological mechanisms as the cells of the interfaces contain various metabolic transporters and efflux pumps, often ATP-binding cassette (ABC

  18. Mechanism of blood-brain barrier impairment after mild traumatic brain injury caused by blast shock waves and its relationship with delayed nerve dysfunction

    Directory of Open Access Journals (Sweden)

    Zhao-xi XU

    2016-06-01

    Full Text Available Mild traumatic brain injury (mTBI caused by blast shock waves (BSWs is one of the most common injuries among soldiers in the war. Such mTBI can also happen in civilians if exposed to shock waves of accidental explosion disasters, bomb attacks by terrorists and so on. This injury often results in cognitive problems, memory dysfunction and emotional disorder, and these neurological deficits are closely related to the dysfunction or disruption of the blood-brain barrier (BBB. The present paper discusses mainly the relationship between dysfunction or disruption of BBB and inflammatory reaction in mild brain injury associated with explosive shock wave and effects of early intervention of oxidative stress injury, repairing the BBB and blocking inflammation on relieving delayed neurological deficits. DOI: 10.11855/j.issn.0577-7402.2016.05.15

  19. Report on the 7th International Conference on Autonomous Infrastructure, Management, and Security (AIMS 2013): Emerging Management Mechanisms for the Future Internet

    NARCIS (Netherlands)

    Doyen, Guillaume; Waldburger, Martin; Sperotto, Anna; Celeda, Pavel; Gorricho, Juan-Luis; Schaaf, Thomas; Serrat, Joan

    2014-01-01

    This article contains the report on AIMS 2013, which was held on June 25–28, 2013 at the Universitat Politècnica de Catalunya (UPC), Spain and was driven by the theme “Emerging Management Mechanisms for the Future Internet”. It covers the three main parts that formed the event program: the keynote a

  20. 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.

  1. Triggering of protection mechanism against Phoneutria nigriventer spider venom in the brain.

    Science.gov (United States)

    Rapôso, Catarina; Odorissi, Paulo Alexandre Miranda; Savioli, Stefania Fioravanti; Hell, Rafaela Chitarra Rodrigues; Simões, Gustavo Ferreira; Ruela-de-Sousa, Roberta R; de Oliveira, Alexandre Leite Rodrigues; da Cruz-Höfling, Maria Alice

    2014-01-01

    Severe accidents caused by the "armed" spider Phoneutria nigriventer cause neurotoxic manifestations in victims. In experiments with rats, P. nigriventer venom (PNV) temporarily disrupts the properties of the BBB by affecting both the transcellular and the paracellular route. However, it is unclear how cells and/or proteins participate in the transient opening of the BBB. The present study demonstrates that PNV is a substrate for the multidrug resistance protein-1 (MRP1) in cultured astrocyte and endothelial cells (HUVEC) and increases mrp1 and cx43 and down-regulates glut1 mRNA transcripts in cultured astrocytes. The inhibition of nNOS by 7-nitroindazole suggests that NO derived from nNOS mediates some of these effects by either accentuating or opposing the effects of PNV. In vivo, MRP1, GLUT1 and Cx43 protein expression is increased differentially in the hippocampus and cerebellum, indicating region-related modulation of effects. PNV contains a plethora of Ca(2+), K(+) and Na(+) channel-acting neurotoxins that interfere with glutamate handling. It is suggested that the findings of the present study are the result of a complex interaction of signaling pathways, one of which is the NO, which regulates BBB-associated proteins in response to PNV interference on ions physiology. The present study provides additional insight into PNV-induced BBB dysfunction and shows that a protective mechanism is activated against the venom. The data shows that PNV has qualities for potential use in drug permeability studies across the BBB.

  2. Voluntary exercise promotes beneficial anti-aging mechanisms in SAMP8 female brain.

    Science.gov (United States)

    Bayod, Sergi; Guzmán-Brambila, Carolina; Sanchez-Roige, Sandra; Lalanza, Jaume F; Kaliman, Perla; Ortuño-Sahagun, Daniel; Escorihuela, Rosa M; Pallàs, Mercè

    2015-02-01

    Regular physical exercise mediates health and longevity promotion involving Sirtuin 1 (SIRT1)-regulated pathways. The anti-aging activity of SIRT1 is achieved, at least in part, by means of fine-tuning the adenosine monophosphate (AMP)-activated protein kinase (AMPK) pathway by preventing the transition of an originally pro-survival program into a pro-aging mechanism. Additionally, SIRT1 promotes mitochondrial function and reduces the production of reactive oxygen species (ROS) through regulating peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), the master controller of mitochondrial biogenesis. Here, by using senescence-accelerated mice prone 8 (SAMP8) as a model for aging, we determined the effect of wheel-running as a paradigm for long-term voluntary exercise on SIRT1-AMPK pathway and mitochondrial functionality measured by oxidative phosphorylation (OXPHOS) complex content in the hippocampus and cortex. We found differential activation of SIRT1 in both tissues and hippocampal-specific activation of AMPK. These findings correlated well with significant changes in OXPHOS in the hippocampal, but not in the cerebral cortex, area. Collectively, the results revealed greater benefits of the exercise in the wheel-running intervention in a murine model of senescence, which was directly related with mitochondrial function and which was mediated through the modulation of SIRT1 and AMPK pathways. PMID:25027560

  3. Triggering of protection mechanism against Phoneutria nigriventer spider venom in the brain.

    Directory of Open Access Journals (Sweden)

    Catarina Rapôso

    Full Text Available Severe accidents caused by the "armed" spider Phoneutria nigriventer cause neurotoxic manifestations in victims. In experiments with rats, P. nigriventer venom (PNV temporarily disrupts the properties of the BBB by affecting both the transcellular and the paracellular route. However, it is unclear how cells and/or proteins participate in the transient opening of the BBB. The present study demonstrates that PNV is a substrate for the multidrug resistance protein-1 (MRP1 in cultured astrocyte and endothelial cells (HUVEC and increases mrp1 and cx43 and down-regulates glut1 mRNA transcripts in cultured astrocytes. The inhibition of nNOS by 7-nitroindazole suggests that NO derived from nNOS mediates some of these effects by either accentuating or opposing the effects of PNV. In vivo, MRP1, GLUT1 and Cx43 protein expression is increased differentially in the hippocampus and cerebellum, indicating region-related modulation of effects. PNV contains a plethora of Ca(2+, K(+ and Na(+ channel-acting neurotoxins that interfere with glutamate handling. It is suggested that the findings of the present study are the result of a complex interaction of signaling pathways, one of which is the NO, which regulates BBB-associated proteins in response to PNV interference on ions physiology. The present study provides additional insight into PNV-induced BBB dysfunction and shows that a protective mechanism is activated against the venom. The data shows that PNV has qualities for potential use in drug permeability studies across the BBB.

  4. Chronic stress and brain plasticity: Mechanisms underlying adaptive and maladaptive changes and implications for stress-related CNS disorders.

    Science.gov (United States)

    Radley, Jason; Morilak, David; Viau, Victor; Campeau, Serge

    2015-11-01

    Stress responses entail neuroendocrine, autonomic, and behavioral changes to promote effective coping with real or perceived threats to one's safety. While these responses are critical for the survival of the individual, adverse effects of repeated exposure to stress are widely known to have deleterious effects on health. Thus, a considerable effort in the search for treatments to stress-related CNS disorders necessitates unraveling the brain mechanisms responsible for adaptation under acute conditions and their perturbations following chronic stress exposure. This paper is based upon a symposium from the 2014 International Behavioral Neuroscience Meeting, summarizing some recent advances in understanding the effects of stress on adaptive and maladaptive responses subserved by limbic forebrain networks. An important theme highlighted in this review is that the same networks mediating neuroendocrine, autonomic, and behavioral processes during adaptive coping also comprise targets of the effects of repeated stress exposure in the development of maladaptive states. Where possible, reference is made to the similarity of neurobiological substrates and effects observed following repeated exposure to stress in laboratory animals and the clinical features of stress-related disorders in humans. PMID:26116544

  5. Understanding deep brain stimulation in obsessive compulsive disorder: A preclinical study into the mechanism of action and behaviour

    NARCIS (Netherlands)

    A. van Dijk

    2013-01-01

    We see a strong impact of deep brain stimulation (DBS) on several aspects of OCD (obsessive compulsive disorder). DBS in different brain areas affects compulsive behaviour, conditioned and unconditioned anxiety. DBS in the internal capsule (IC) shows the most promising behavioural results by uniquel

  6. The cost of brain diseases

    DEFF Research Database (Denmark)

    DiLuca, Monica; Olesen, Jes

    2014-01-01

    Brain diseases represent a considerable social and economic burden in Europe. With yearly costs of about 800 billion euros and an estimated 179 million people afflicted in 2010, brain diseases are an unquestionable emergency and a grand challenge for neuroscientists.......Brain diseases represent a considerable social and economic burden in Europe. With yearly costs of about 800 billion euros and an estimated 179 million people afflicted in 2010, brain diseases are an unquestionable emergency and a grand challenge for neuroscientists....

  7. Use of non-invasive mechanical ventilation in the Emergency Department, clinical outcomes and correlates of failure

    Directory of Open Access Journals (Sweden)

    Paolo Groff

    2008-09-01

    Full Text Available

    Background: Despite several studies having been carried in this organizational context, there is an absence of information about the effectiveness of non-invasive mechanical ventilation (NIV in Emergency Departments (ED, based on a number of suitable patients with acute respiratory failure (ARF of different aetiology. In particular, it has not yet been defined as to whether the context of the ED suits the necessary requirement of quality for the correct application of the method and if the obtained results are different from those taken in other studies in general or respiratory intensive care unit. Finally there are few data related to the predictive factors to NIV failure (endotracheal intubation, in-hospital mortality when applied in the emergency setting.

    Methods: To answer these questions we have retrospectively studied a population of 210 patients (95 with COPD exsacerbation ; 92 with acute cardiogenic pulmonary oedema; 23 with severe community acquired pneumonia treated for ARF in the “critical area” of four Italian level II Emergency Departments. For all patients demographic data; some comorbidities (diabetes, dementia, sopraventricular arrhythmias, obesity; the physiological scores (Kelly, SAPS II, Apache II; the need for pharmacological sedation; vital and blood gas parameters (evaluated at entry, after one hour of treatment and before its suspension; the ventilatory modality applied (CPAP or PSV + PEEP and some parameters of in-hospital stay (duration of the hospitalization in the critical area, duration of ventilation, compliance to the treatment, patient's refusal to continue it, development of skin necrosis, need for endotracheal intubation, in-hospital mortality were considered. Finally demographic, event of death with Cox regression or to the need for ETI through linear regression analysis.

    Results: Globally, in-hospital mortality reached 13,3%, the percentage

  8. Brain evolution by brain pathway duplication

    OpenAIRE

    Chakraborty, Mukta; Jarvis, Erich D

    2015-01-01

    Understanding the mechanisms of evolution of brain pathways for complex behaviours is still in its infancy. Making further advances requires a deeper understanding of brain homologies, novelties and analogies. It also requires an understanding of how adaptive genetic modifications lead to restructuring of the brain. Recent advances in genomic and molecular biology techniques applied to brain research have provided exciting insights into how complex behaviours are shaped by selection of novel ...

  9. Discussion on Mechanical Emergency Start of Fire Pump%消防泵机械应急启泵装置探讨

    Institute of Scientific and Technical Information of China (English)

    徐建兵; 李慧

    2015-01-01

    收集整理有关消防水泵控制柜应设置机械应急启泵功能要求的国内外相关标准;介绍美国Joslyn Clark消防泵控制柜机械应急启泵装置的设置;总结电源系统及消防泵控制柜各功能组件的性能要求。%This paper collects and analyzes the international and national standards related to the requirement of mechanical emergency startup function for control cabinet of fire pump, introduces the settings of mechanical emergency starter of Joslyn Clark fire pump control cabinet, and summarizes the functional requirements for functional components of power system and control cabinet of fire pump.

  10. Framework and Bio-Mechanical Model for a Per-Operative Image-Guided Neuronavigator Including 'Brain-Shift' Compensation

    CERN Document Server

    Bucki, M; Bucki, Marek; Payan, Yohan

    2006-01-01

    In this paper we present a methodology to adress the problem of brain tissue deformation referred to as "brainshift". This deformation occurs throughout a neurosurgery intervention and strongly alters the accuracy of the neuronavigation systems used to date in clinical routine which rely solely on preoperative patient imaging to locate the surgical target, such as a tumour or a functional area. After a general description of the framework of our intraoperative image-guided system, we propose a biomechanical model of the brain which can take into account interactively such deformations as well as surgical procedures that modify the brain structure, like tumour or tissue resection.

  11. Firms' innovation capability‐building paths and the nature of changes in learning mechanisms : multiple case-study evidence from an emerging economy

    OpenAIRE

    Figueiredo, P. N.; Cohen, M.; Gomes, S

    2013-01-01

    Although much has been written about organizational-level learning, there is a dearth of empirical studies that explore the role of changes in the nature of firm-centred learning mechanisms in affecting inter-firm differences and similarities in the accumulation of innovation capabilities, especially among firms from emerging economies, known as latecomers. By examining the relationships between these issues based on fieldwork evidence from 13 natural resource-processing firms in Brazil (1950...

  12. The Mechanical Activation of mTOR Signaling: An Emerging Role for Late Endosome/Lysosomal Targeting

    OpenAIRE

    Jacobs, Brittany L.; Goodman, Craig A.; Hornberger, Troy A.

    2013-01-01

    It is well recognized that mechanical signals play a critical role in the regulation of skeletal muscle mass, and the maintenance of muscle mass is essential for mobility, disease prevention and quality of life. Furthermore, over the last 15 years it has become established that signaling through a protein kinase called the mammalian [or mechanistic] Target of Rapamycin (mTOR) is essential for mechanically-induced changes in protein synthesis and muscle mass, however, the mechanism(s) via whic...

  13. Lung Emergencies

    Science.gov (United States)

    ... Emergencies Cardiac Emergencies Eye Emergencies Lung Emergencies Surgeries Lung Emergencies People with Marfan syndrome can be at ... should be considered an emergency. Symptoms of sudden lung collapse (pneumothorax) Symptoms of a sudden lung collapse ...

  14. Numerical Modeling of Cloud Convection in Jupiter's Atmosphere: robustness and a mechanism of the intermittent emergence of vigorous cumulonimbus clouds

    Science.gov (United States)

    Sugiyama, K.; Nakajima, K.; Odaka, M.; Ishiwatari, M.; Kuramoto, K.; Nishizawa, S.; Takahashi, Y. O.; Hayashi, Y.

    2012-12-01

    The mean structure of cloud layer of Jupiter's atmosphere is thought to be maintained by the statistical contribution of a large number of clouds driven by internal and radiative heating/cooling over multiple cloud life cycles. The mean structure and its relationship to cloud convection remain unclear, because it is difficult to observe the structure under the extensive surface cloud layer by remote sensing. Sugiyama et al. (2009) develop a two-dimensional numerical fluid model that incorporates condensation of H2O and NH3 and production reaction of NH4SH, and Sugiyama et al. (2011) investigate a possible cloud layer structure with thermal forcing whose intensity is of the order of that expected in the real Jupiter's atmosphere. The purpose of this study is to confirm robustness of the characteristics of the structure demonstrated by Sugiyama et al. (2011) and to discuss a mechanism that causes their most remarkable characteristic, intermittent emergence of vigorous cumulonimbus clouds. Many long-term numerical calculations are performed in order to examine the dependency of the structure of cloud layer on both key parameter of cloud microphysics and abundance of condensible gases in the sub-cloud layer. In the parameter study about the time scale of conversion from cloud to rain, the intermittent cloud activity exists. In the parameter study about the abundance of the condensible gases in sub-cloud layer, the intermittent cloud activity exists except for the case in which the abundance of condensible gases is extremely small. The period of the intermittency is roughly proportional to the abundance of H2O gas in the sub-cloud layer. As the abundance of condensible gases increases, the condensation levels and the formation level become stronger barrier for the vertical convective motion. Our results do not reproduce the Galileo probe observation that all of the condensible gases are significantly depleted below the H2O condensation level. The trigger that starts

  15. Fetal Stress and Programming of Hypoxic/Ischemic-Sensitive Phenotype in the Neonatal Brain: Mechanisms and Possible Interventions

    OpenAIRE

    Li, Yong; Gonzalez, Pablo; Zhang, Lubo

    2012-01-01

    Growing evidence of epidemiological, clinical and experimental studies has clearly shown a close link between adverse in utero environment and the increased risk of neurological, psychological and psychiatric disorders in later life. Fetal stresses, such as hypoxia, malnutrition, and fetal exposure to nicotine, alcohol, cocaine and glucocorticoids may directly or indirectly act at cellular and molecular levels to alter the brain development and result in programming of heightened brain vulner...

  16. The low levels of eicosapentaenoic acid in rat brain phospholipids are maintained via multiple redundant mechanisms[S

    OpenAIRE

    Chen, Chuck T; Domenichiello, Anthony F.; Trépanier, Marc-Olivier; Liu, Zhen; Masoodi, Mojgan; Bazinet, Richard P.

    2013-01-01

    Brain eicosapentaenoic acid (EPA) levels are 250- to 300-fold lower than docosahexaenoic acid (DHA), at least partly, because EPA is rapidly β-oxidized and lost from brain phospholipids. Therefore, we examined if β-oxidation was necessary for maintaining low EPA levels by inhibiting β-oxidation with methyl palmoxirate (MEP). Furthermore, because other metabolic differences between DHA and EPA may also contribute to their vastly different levels, this study aimed to quantify the incorporation ...

  17. Understanding deep brain stimulation in obsessive compulsive disorder: A preclinical study into the mechanism of action and behaviour

    OpenAIRE

    Dijk, van, G.

    2013-01-01

    We see a strong impact of deep brain stimulation (DBS) on several aspects of OCD (obsessive compulsive disorder). DBS in different brain areas affects compulsive behaviour, conditioned and unconditioned anxiety. DBS in the internal capsule (IC) shows the most promising behavioural results by uniquely reducing conditioned anxiety and by shortening the compulsive grooming bout in the sapap3 mutant mouse. This suggests that the IC is possibly the best target for DBS in relation to OCD. Further r...

  18. Time-Course Analysis of Brain Regional Expression Network Responses to Chronic Intermittent Ethanol and Withdrawal: Implications for Mechanisms Underlying Excessive Ethanol Consumption.

    Science.gov (United States)

    Smith, Maren L; Lopez, Marcelo F; Archer, Kellie J; Wolen, Aaron R; Becker, Howard C; Miles, Michael F

    2016-01-01

    Long lasting abusive consumption, dependence, and withdrawal are characteristic features of alcohol use disorders (AUD). Mechanistically, persistent changes in gene expression are hypothesized to contribute to brain adaptations leading to ethanol toxicity and AUD. We employed repeated chronic intermittent ethanol (CIE) exposure by vapor chamber as a mouse model to simulate the cycles of ethanol exposure and withdrawal commonly seen with AUD. This model has been shown to induce progressive ethanol consumption in rodents. Brain CIE-responsive expression networks were identified by microarray analysis across five regions of the mesolimbic dopamine system and extended amygdala with tissue harvested from 0-hours to 7-days following CIE. Weighted Gene Correlated Network Analysis (WGCNA) was used to identify gene networks over-represented for CIE-induced temporal expression changes across brain regions. Differential gene expression analysis showed that long-lasting gene regulation occurred 7-days after the final cycle of ethanol exposure only in prefrontal cortex (PFC) and hippocampus. Across all brain regions, however, ethanol-responsive expression changes occurred mainly within the first 8-hours after removal from ethanol. Bioinformatics analysis showed that neuroinflammatory responses were seen across multiple brain regions at early time-points, whereas co-expression modules related to neuroplasticity, chromatin remodeling, and neurodevelopment were seen at later time-points and in specific brain regions (PFC or HPC). In PFC a module containing Bdnf was identified as highly CIE responsive in a biphasic manner, with peak changes at 0 hours and 5 days following CIE, suggesting a possible role in mechanisms underlying long-term molecular and behavioral response to CIE. Bioinformatics analysis of this network and several other modules identified Let-7 family microRNAs as potential regulators of gene expression changes induced by CIE. Our results suggest a complex temporal

  19. Time-Course Analysis of Brain Regional Expression Network Responses to Chronic Intermittent Ethanol and Withdrawal: Implications for Mechanisms Underlying Excessive Ethanol Consumption.

    Directory of Open Access Journals (Sweden)

    Maren L Smith

    Full Text Available Long lasting abusive consumption, dependence, and withdrawal are characteristic features of alcohol use disorders (AUD. Mechanistically, persistent changes in gene expression are hypothesized to contribute to brain adaptations leading to ethanol toxicity and AUD. We employed repeated chronic intermittent ethanol (CIE exposure by vapor chamber as a mouse model to simulate the cycles of ethanol exposure and withdrawal commonly seen with AUD. This model has been shown to induce progressive ethanol consumption in rodents. Brain CIE-responsive expression networks were identified by microarray analysis across five regions of the mesolimbic dopamine system and extended amygdala with tissue harvested from 0-hours to 7-days following CIE. Weighted Gene Correlated Network Analysis (WGCNA was used to identify gene networks over-represented for CIE-induced temporal expression changes across brain regions. Differential gene expression analysis showed that long-lasting gene regulation occurred 7-days after the final cycle of ethanol exposure only in prefrontal cortex (PFC and hippocampus. Across all brain regions, however, ethanol-responsive expression changes occurred mainly within the first 8-hours after removal from ethanol. Bioinformatics analysis showed that neuroinflammatory responses were seen across multiple brain regions at early time-points, whereas co-expression modules related to neuroplasticity, chromatin remodeling, and neurodevelopment were seen at later time-points and in specific brain regions (PFC or HPC. In PFC a module containing Bdnf was identified as highly CIE responsive in a biphasic manner, with peak changes at 0 hours and 5 days following CIE, suggesting a possible role in mechanisms underlying long-term molecular and behavioral response to CIE. Bioinformatics analysis of this network and several other modules identified Let-7 family microRNAs as potential regulators of gene expression changes induced by CIE. Our results suggest a

  20. Is brain copper deficiency in Alzheimer's, Lewy body, and Creutzfeldt Jakob diseases the common key for a free radical mechanism and oxidative stress-induced damage?

    Science.gov (United States)

    Deloncle, Roger; Guillard, Olivier

    2015-01-01

    In Alzheimer's (AD), Lewy body (LBD), and Creutzfeldt Jakob (CJD) diseases, similar pathological hallmarks have been described, one of which is brain deposition of abnormal protease-resistant proteins. For these pathologies, copper bound to proteins is able to protect against free radicals by reduction from cupric Cu++ to cupreous Cu+. We have previously demonstrated in bovine brain homogenate that free radicals produce proteinase K-resistant prion after manganese is substituted for copper. Since low brain copper levels have been described in transmissible spongiform encephalopathies, in substantia nigra in Parkinson's disease, and in various brain regions in AD, LBD, and CJD, a mechanism has been proposed that may underlie the neurodegenerative processes that occur when copper protection against free radicals is impaired. In peptide sequences, the alpha acid proton near the peptide bond is highly mobile and can be pulled out by free radicals. It will produce a trivalent α-carbon radical and induce a free radical chain process that will generate a D-amino acid configuration in the peptide sequence. Since only L-amino acids are physiologically present in mammalian (human) proteins, it may be supposed that only physiological L-peptides can be recycled by physiological enzymes such as proteases. If a D-amino acid is found in the peptide sequence subsequent to deficient copper protection against free radicals, it will not be recognized and might alter the proteasome L-amino acid recycling from brain peptides. In the brain, there will result an accumulation of abnormal protease-resistant proteins such as those observed in AD, LBD, and CJD.

  1. Time-Course Analysis of Brain Regional Expression Network Responses to Chronic Intermittent Ethanol and Withdrawal: Implications for Mechanisms Underlying Excessive Ethanol Consumption.

    Science.gov (United States)

    Smith, Maren L; Lopez, Marcelo F; Archer, Kellie J; Wolen, Aaron R; Becker, Howard C; Miles, Michael F

    2016-01-01

    Long lasting abusive consumption, dependence, and withdrawal are characteristic features of alcohol use disorders (AUD). Mechanistically, persistent changes in gene expression are hypothesized to contribute to brain adaptations leading to ethanol toxicity and AUD. We employed repeated chronic intermittent ethanol (CIE) exposure by vapor chamber as a mouse model to simulate the cycles of ethanol exposure and withdrawal commonly seen with AUD. This model has been shown to induce progressive ethanol consumption in rodents. Brain CIE-responsive expression networks were identified by microarray analysis across five regions of the mesolimbic dopamine system and extended amygdala with tissue harvested from 0-hours to 7-days following CIE. Weighted Gene Correlated Network Analysis (WGCNA) was used to identify gene networks over-represented for CIE-induced temporal expression changes across brain regions. Differential gene expression analysis showed that long-lasting gene regulation occurred 7-days after the final cycle of ethanol exposure only in prefrontal cortex (PFC) and hippocampus. Across all brain regions, however, ethanol-responsive expression changes occurred mainly within the first 8-hours after removal from ethanol. Bioinformatics analysis showed that neuroinflammatory responses were seen across multiple brain regions at early time-points, whereas co-expression modules related to neuroplasticity, chromatin remodeling, and neurodevelopment were seen at later time-points and in specific brain regions (PFC or HPC). In PFC a module containing Bdnf was identified as highly CIE responsive in a biphasic manner, with peak changes at 0 hours and 5 days following CIE, suggesting a possible role in mechanisms underlying long-term molecular and behavioral response to CIE. Bioinformatics analysis of this network and several other modules identified Let-7 family microRNAs as potential regulators of gene expression changes induced by CIE. Our results suggest a complex temporal

  2. New Heuristics for Interfacing Human Motor System using Brain Waves

    Directory of Open Access Journals (Sweden)

    Mohammed El-Dosuky

    2012-09-01

    Full Text Available There are many new forms of interfacing human users to machines. We persevere here electric-mechanical form of interaction between human and machine. The emergence of brain-computer interface allows mind-to-movement systems. The story of the Pied Piper inspired us to devise some new heuristics for interfacing human motor system using brain waves, by combining head helmet and LumbarMotionMonitor. For the simulation we use java GridGain. Brain responses of classified subjects during training indicates that Probe can be the best stimulus to rely on in distinguishing between knowledgeable and not knowledgeable

  3. New Heuristics for Interfacing Human Motor System using Brain Waves

    OpenAIRE

    Mohammed El-Dosuky; Ahmed El-Bassiouny; Taher Hamza; Magdy Rashad

    2012-01-01

    There are many new forms of interfacing human users to machines. We persevere here electric-mechanical form of interaction between human and machine. The emergence of brain-computer interface allows mind-to-movement systems. The story of the Pied Piper inspired us to devise some new heuristics for interfacing human motor system using brain waves, by combining head helmet and LumbarMotionMonitor. For the simulation we use java GridGain. Brain responses of classified subjects during training in...

  4. Adsorption Mechanisms of Emerging Micro-pollutants with a clay Mineral: Case of Tramadol and Doxepine Pharmaceutical Products

    OpenAIRE

    Thiebault, Thomas; Guégan, Régis; Boussafir, Mohammed

    2015-01-01

    International audience A sodium exchanged smectite clay mineral (Mt) was used as geo-sorbent for the adsorption of tramadol and doxepin: two pharmaceutical products (PPs) defined as emerging pollutants due to their presence at significant concentration in numerous water compartments. The adsorption isotherms for both the temperatures of 20 and 40 °C and the derived data determined through the fitting procedure by using Langmuir, Freundlich and Dubinin–Radushkevich equation models explicitl...

  5. Reaction with glutathione. A possible mechanism involved in rodent brain retention of a 99mTc SNS/S complex containing a pendant ester functionality

    International Nuclear Information System (INIS)

    The synthesis, characterization of MvO([CH3CH2N(CH2CH2S)2](p-S-Ph-COOCH2-CH3)) (M:99mTc: I, Re: II) is presented in this work, where a pendant ester function is attached to the monothiolate ligand. Chemical structure of I is established after chromatographic comparison with II, synthesized in macroscopic amounts. Complex II is fully characterized by classical methods of analysis showing that the compound adopts a distorted trigonal bipyramidal configuration around the metal. The two sulfur atoms of the tridentate ligand and the oxo group form the basal plane, while the remaining nitrogen atom of the tridentate ligand and the sulfur atom of the monothiolate ligand occupy the apices of the bipyramid. In vitro challenge experiments with glutathione (GSH) in neutral aqueous medium demonstrate, that I suffers nucleophilic attack by GSH and thereby transformation to a more hydrophilic daughter metal compound. Formation of the latter depends on time and GSH concentration. Tissue distribution in mice shows minor retention in brain. As rodent brain presents no esterases to hydrolyze the ester group of I, while the intracerebral content in GSH amounts to 2 mM, the above described mechanism is suspected for the observed brain retention. However, in primate brain cells retention of I may additionally involve the hydrolysis of the ester function to the corresponding acid, as already revealed by preliminary in vitro experiments using esterase incubates. (author)

  6. Social Plasticity Relies on Different Neuroplasticity Mechanisms across the Brain Social Decision-Making Network in Zebrafish

    Science.gov (United States)

    Teles, Magda C.; Cardoso, Sara D.; Oliveira, Rui F.

    2016-01-01

    Social living animals need to adjust the expression of their behavior to their status within the group and to changes in social context and this ability (social plasticity) has an impact on their Darwinian fitness. At the proximate level social plasticity must rely on neuroplasticity in the brain social decision-making network (SDMN) that underlies the expression of social behavior, such that the same neural circuit may underlie the expression of different behaviors depending on social context. Here we tested this hypothesis in zebrafish by characterizing the gene expression response in the SDMN to changes in social status of a set of genes involved in different types of neural plasticity: bdnf, involved in changes in synaptic strength; npas4, involved in contextual learning and dependent establishment of GABAergic synapses; neuroligins (nlgn1 and nlgn2) as synaptogenesis markers; and genes involved in adult neurogenesis (wnt3 and neurod). Four social phenotypes were experimentally induced: Winners and Losers of a real-opponent interaction; Mirror-fighters, that fight their own image in a mirror and thus do not experience a change in social status despite the expression of aggressive behavior; and non-interacting fish, which were used as a reference group. Our results show that each social phenotype (i.e., Winners, Losers, and Mirror-fighters) present specific patterns of gene expression across the SDMN, and that different neuroplasticity genes are differentially expressed in different nodes of the network (e.g., BDNF in the dorsolateral telencephalon, which is a putative teleost homolog of the mammalian hippocampus). Winners expressed unique patterns of gene co-expression across the SDMN, whereas in Losers and Mirror-fighters the co-expression patterns were similar in the dorsal regions of the telencephalon and in the supracommissural nucleus of the ventral telencephalic area, but differents in the remaining regions of the ventral telencephalon. These results

  7. Social Plasticity Relies on Different Neuroplasticity Mechanisms across the Brain Social Decision-Making Network in Zebrafish.

    Science.gov (United States)

    Teles, Magda C; Cardoso, Sara D; Oliveira, Rui F

    2016-01-01

    Social living animals need to adjust the expression of their behavior to their status within the group and to changes in social context and this ability (social plasticity) has an impact on their Darwinian fitness. At the proximate level social plasticity must rely on neuroplasticity in the brain social decision-making network (SDMN) that underlies the expression of social behavior, such that the same neural circuit may underlie the expression of different behaviors depending on social context. Here we tested this hypothesis in zebrafish by characterizing the gene expression response in the SDMN to changes in social status of a set of genes involved in different types of neural plasticity: bdnf, involved in changes in synaptic strength; npas4, involved in contextual learning and dependent establishment of GABAergic synapses; neuroligins (nlgn1 and nlgn2) as synaptogenesis markers; and genes involved in adult neurogenesis (wnt3 and neurod). Four social phenotypes were experimentally induced: Winners and Losers of a real-opponent interaction; Mirror-fighters, that fight their own image in a mirror and thus do not experience a change in social status despite the expression of aggressive behavior; and non-interacting fish, which were used as a reference group. Our results show that each social phenotype (i.e., Winners, Losers, and Mirror-fighters) present specific patterns of gene expression across the SDMN, and that different neuroplasticity genes are differentially expressed in different nodes of the network (e.g., BDNF in the dorsolateral telencephalon, which is a putative teleost homolog of the mammalian hippocampus). Winners expressed unique patterns of gene co-expression across the SDMN, whereas in Losers and Mirror-fighters the co-expression patterns were similar in the dorsal regions of the telencephalon and in the supracommissural nucleus of the ventral telencephalic area, but differents in the remaining regions of the ventral telencephalon. These results

  8. Borneol Depresses P-Glycoprotein Function by a NF-κB Signaling Mediated Mechanism in a Blood Brain Barrier in Vitro Model.

    Science.gov (United States)

    Fan, Xiang; Chai, Lijuan; Zhang, Han; Wang, Yuefei; Zhang, Boli; Gao, Xiumei

    2015-11-18

    P-glycoprotein (P-gp) on brain microvascular endothelial cells (BMECs) that form the blood brain barrier (BBB), influences transportation of substances between blood and brain. The objective of this study was to characterize the effects of borneol on P-gp efflux function on BBB and explore the potential mechanisms. We established an in vitro BBB model comprised of rat BMECs and astrocytes to measure the effects of borneol on the known P-gp substrates transport across BBB, and examined the function and expression of P-gp in BMECs and the signaling pathways regulating P-gp expression. Borneol increased intracellular accumulation of Rhodamine 123, enhanced verapamil and digoxin across the BBB in vitro model, and depressed mdr1a mRNA and P-gp expression. Borneol could activate nuclear factor-κB (NF-κB) and inhibition of NF-κB with MG132 (carbobenzoxy-Leu-Leu-leucinal) and SN50 (an inhibitory peptide) obscuring the P-gp decreases induced by borneol. These data suggested that borneol depresses P-gp function in BMECs by a NF-κB signaling medicated mechanism in a BBB in vitro model.

  9. Borneol Depresses P-Glycoprotein Function by a NF-κB Signaling Mediated Mechanism in a Blood Brain Barrier in Vitro Model

    Directory of Open Access Journals (Sweden)

    Xiang Fan

    2015-11-01

    Full Text Available P-glycoprotein (P-gp on brain microvascular endothelial cells (BMECs that form the blood brain barrier (BBB, influences transportation of substances between blood and brain. The objective of this study was to characterize the effects of borneol on P-gp efflux function on BBB and explore the potential mechanisms. We established an in vitro BBB model comprised of rat BMECs and astrocytes to measure the effects of borneol on the known P-gp substrates transport across BBB, and examined the function and expression of P-gp in BMECs and the signaling pathways regulating P-gp expression. Borneol increased intracellular accumulation of Rhodamine 123, enhanced verapamil and digoxin across the BBB in vitro model, and depressed mdr1a mRNA and P-gp expression. Borneol could activate nuclear factor-κB (NF-κB and inhibition of NF-κB with MG132 (carbobenzoxy-Leu-Leu-leucinal and SN50 (an inhibitory peptide obscuring the P-gp decreases induced by borneol. These data suggested that borneol depresses P-gp function in BMECs by a NF-κB signaling medicated mechanism in a BBB in vitro model.

  10. Cryptococcal transmigration across a model brain blood-barrier: evidence of the Trojan horse mechanism and differences between Cryptococcus neoformans var. grubii strain H99 and Cryptococcus gattii strain R265.

    Science.gov (United States)

    Sorrell, Tania C; Juillard, Pierre-Georges; Djordjevic, Julianne T; Kaufman-Francis, Keren; Dietmann, Anelia; Milonig, Alban; Combes, Valery; Grau, Georges E R

    2016-01-01

    Cryptococcus neoformans (Cn) and Cryptococcus gattii (Cg) cause neurological disease and cross the BBB as free cells or in mononuclear phagocytes via the Trojan horse mechanism, although evidence for the latter is indirect. There is emerging evidence that Cn and the North American outbreak Cg strain (R265) more commonly cause neurological and lung disease, respectively. We have employed a widely validated in vitro model of the BBB, which utilizes the hCMEC/D3 cell line derived from human brain endothelial cells (HBEC) and the human macrophage-like cell line, THP-1, to investigate whether transport of dual fluorescence-labelled Cn and Cg across the BBB occurs within macrophages. We showed that phagocytosis of Cn by non-interferon (IFN)-γ stimulated THP-1 cells was higher than that of Cg. Although Cn and Cg-loaded THP-1 bound similarly to TNF-activated HBECs under shear stress, more Cn-loaded macrophages were transported across an intact HBEC monolayer, consistent with the predilection of Cn for CNS infection. Furthermore, Cn exhibited a higher rate of expulsion from transmigrated THP-1 compared with Cg. Our results therefore provide further evidence for transmigration of both Cn and Cg via the Trojan horse mechanism and a potential explanation for the predilection of Cn to cause CNS infection. PMID:26369713

  11. Neuropathophysiology of Brain Injury.

    Science.gov (United States)

    Quillinan, Nidia; Herson, Paco S; Traystman, Richard J

    2016-09-01

    Every year in the United States, millions of individuals incur ischemic brain injury from stroke, cardiac arrest, or traumatic brain injury. These acquired brain injuries can lead to death or long-term neurologic and neuropsychological impairments. The mechanisms of ischemic and traumatic brain injury that lead to these deficiencies result from a complex interplay of interdependent molecular pathways, including excitotoxicity, acidotoxicity, ionic imbalance, oxidative stress, inflammation, and apoptosis. This article reviews several mechanisms of brain injury and discusses recent developments. Although much is known from animal models of injury, it has been difficult to translate these effects to humans. PMID:27521191

  12. NASA Robot Brain Surgeon

    Science.gov (United States)

    1997-01-01

    Mechanical Engineer Michael Guerrero works on the Robot Brain Surgeon testbed in the NeuroEngineering Group at the Ames Research Center, Moffett Field, California. Principal investigator Dr. Robert W. Mah states that potentially the simple robot will be able to feel brain structures better than any human surgeon, making slow, very precise movements during an operation. The brain surgery robot that may give surgeons finer control of surgical instruments during delicate brain operations is still under development.

  13. 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

  14. 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

  15. Protection of Vascular Endothelial Growth Factor to Brain Edema Following Intracerebral Hemorrhage and Its Involved Mechanisms: Effect of Aquaporin-4.

    Directory of Open Access Journals (Sweden)

    Heling Chu

    Full Text Available Vascular endothelial growth factor (VEGF has protective effects on many neurological diseases. However, whether VEGF acts on brain edema following intracerebral hemorrhage (ICH is largely unknown. Our previous study has shown aquaporin-4 (AQP4 plays an important role in brain edema elimination following ICH. Meanwhile, there is close relationship between VEGF and AQP4. In this study, we aimed to test effects of VEGF on brain edema following ICH and examine whether they were AQP4 dependent. Recombinant human VEGF165 (rhVEGF165 was injected intracerebroventricularly 1 d after ICH induced by microinjecting autologous whole blood into striatum. We detected perihemotomal AQP4 protein expression, then examined the effects of rhVEGF165 on perihemotomal brain edema at 1 d, 3 d, and 7 d after injection in wild type (AQP4(+/+ and AQP4 knock-out (AQP4(-/- mice. Furthermore, we assessed the possible signal transduction pathways activated by VEGF to regulate AQP4 expression via astrocyte cultures. We found perihemotomal AQP4 protein expression was highly increased by rhVEGF165. RhVEGF165 alleviated perihemotomal brain edema in AQP4(+/+ mice at each time point, but had no effect on AQP4(-/- mice. Perihemotomal EB extravasation was increased by rhVEGF165 in AQP4(-/- mice, but not AQP4(+/+ mice. RhVEGF165 reduced neurological deficits and increased Nissl's staining cells surrounding hemotoma in both types of mice and these effects were related to AQP4. RhVEGF165 up-regulated phospharylation of C-Jun amino-terminal kinase (p-JNK and extracellular signal-regulated kinase (p-ERK and AQP4 protein in cultured astrocytes. The latter was inhibited by JNK and ERK inhibitors. In conclusion, VEGF reduces neurological deficits, brain edema, and neuronal death surrounding hemotoma but has no influence on BBB permeability. These effects are closely related to AQP4 up-regulation, possibly through activating JNK and ERK pathways. The current study may present new insights to

  16. Brain Basics

    Medline Plus

    Full Text Available ... News About Us Home > Health & Education > Educational Resources Brain Basics Introduction The Growing Brain The Working Brain ... to mental disorders, such as depression. The Growing Brain Inside the Brain: Neurons & Neural Circuits Neurons are ...

  17. Brain Basics

    Science.gov (United States)

    ... News About Us Home > Health & Education > Educational Resources Brain Basics Introduction The Growing Brain The Working Brain ... to mental disorders, such as depression. The Growing Brain Inside the Brain: Neurons & Neural Circuits Neurons are ...

  18. Brain Basics

    Medline Plus

    Full Text Available ... Brain Basics provides information on how the brain works, how mental illnesses are disorders of the brain, ... learning more about how the brain grows and works in healthy people, and how normal brain development ...

  19. Modulation of Gut Microbiota-Brain Axis by Probiotics, Prebiotics, and Diet.

    Science.gov (United States)

    Liu, Xiaofei; Cao, Shangqing; Zhang, Xuewu

    2015-09-16

    There exists a bidirectional communication system between the gastrointestinal tract and the brain. Increasing evidence shows that gut microbiota can play a critical role in this communication; thus, the concept of a gut microbiota and brain axis is emerging. Here, we review recent findings in the relationship between intestinal microbes and brain function, such as anxiety, depression, stress, autism, learning, and memory. We highlight the advances in modulating brain development and behavior by probiotics, prebiotics, and diet through the gut microbiota-brain axis. A variety of mechanisms including immune, neural, and metabolic pathways may be involved in modulation of the gut microbiota-brain axis. We also discuss some future challenges. A deeper understanding of the relationship between the gut bacteria and their hosts is implicated in developing microbial-based therapeutic strategies for brain disorders.

  20. Orchestrating Proactive and Reactive Mechanisms for Filtering Distracting Information: Brain-Behavior Relationships Revealed by a Mixed-Design fMRI Study.

    Science.gov (United States)

    Marini, Francesco; Demeter, Elise; Roberts, Kenneth C; Chelazzi, Leonardo; Woldorff, Marty G

    2016-01-20

    Given the information overload often imparted to human cognitive-processing systems, suppression of irrelevant and distracting information is essential for successful behavior. Using a hybrid block/event-related fMRI design, we characterized proactive and reactive brain mechanisms for filtering distracting stimuli. Participants performed a flanker task, discriminating the direction of a target arrow in the presence versus absence of congruent or incongruent flanking distracting arrows during either Pure blocks (distracters always absent) or Mixed blocks (distracters on 80% of trials). Each Mixed block had either 20% or 60% incongruent trials. Activations in the dorsal frontoparietal attention network during Mixed versus Pure blocks evidenced proactive (blockwise) recruitment of a distraction-filtering mechanism. Sustained activations in right middle frontal gyrus during 60% Incongruent blocks correlated positively with behavioral indices of distraction-filtering (slowing when distracters might occur) and negatively with distraction-related behavioral costs (incongruent vs congruent trials), suggesting a role in coordinating proactive filtering of potential distracters. Event-related analyses showed that incongruent trials elicited greater reactive activations in 20% (vs 60%) Incongruent blocks for counteracting distraction and conflict, including in the insula and anterior cingulate. Context-related effects in occipitoparietal cortex consisted of greater target-evoked activations for distracter-absent trials (central-target-only) in Mixed versus Pure blocks, suggesting enhanced attentional engagement. Functional-localizer analyses in V1/V2/V3 revealed less distracter-processing activity in 60% (vs 20%) Incongruent blocks, presumably reflecting tonic suppression by proactive filtering mechanisms. These results delineate brain mechanisms underlying proactive and reactive filtering of distraction and conflict, and how they are orchestrated depending on distraction

  1. Orchestrating Proactive and Reactive Mechanisms for Filtering Distracting Information: Brain-Behavior Relationships Revealed by a Mixed-Design fMRI Study.

    Science.gov (United States)

    Marini, Francesco; Demeter, Elise; Roberts, Kenneth C; Chelazzi, Leonardo; Woldorff, Marty G

    2016-01-20

    Given the information overload often imparted to human cognitive-processing systems, suppression of irrelevant and distracting information is essential for successful behavior. Using a hybrid block/event-related fMRI design, we characterized proactive and reactive brain mechanisms for filtering distracting stimuli. Participants performed a flanker task, discriminating the direction of a target arrow in the presence versus absence of congruent or incongruent flanking distracting arrows during either Pure blocks (distracters always absent) or Mixed blocks (distracters on 80% of trials). Each Mixed block had either 20% or 60% incongruent trials. Activations in the dorsal frontoparietal attention network during Mixed versus Pure blocks evidenced proactive (blockwise) recruitment of a distraction-filtering mechanism. Sustained activations in right middle frontal gyrus during 60% Incongruent blocks correlated positively with behavioral indices of distraction-filtering (slowing when distracters might occur) and negatively with distraction-related behavioral costs (incongruent vs congruent trials), suggesting a role in coordinating proactive filtering of potential distracters. Event-related analyses showed that incongruent trials elicited greater reactive activations in 20% (vs 60%) Incongruent blocks for counteracting distraction and conflict, including in the insula and anterior cingulate. Context-related effects in occipitoparietal cortex consisted of greater target-evoked activations for distracter-absent trials (central-target-only) in Mixed versus Pure blocks, suggesting enhanced attentional engagement. Functional-localizer analyses in V1/V2/V3 revealed less distracter-processing activity in 60% (vs 20%) Incongruent blocks, presumably reflecting tonic suppression by proactive filtering mechanisms. These results delineate brain mechanisms underlying proactive and reactive filtering of distraction and conflict, and how they are orchestrated depending on distraction

  2. An early illustrated comparative anatomy of the brain: Samuel Collins' A Systeme of Anatomy (1685) and the emergence of comparative neurology in 17th century England.

    Science.gov (United States)

    Kruger, Lawrence

    2004-09-01

    The concept of comparing of the brains of various animals and of individual human brains was launched in the last half of the 17th century in England and was much influenced by the formation of the European scientific societies and their attempts to guide naturalist observations into a new systematics. An ambitious attempt to document this trend in an extensively illustrated work of encyclopedic pretensions was the singular publication of Samuel Collins (1618-1710), an energetic anatomist and president of the Royal College of Physicians. His little known tow-volume folio presentation, written in teh vernacular for broad acceptance, contains the seeds of a science of comparative neurology with the largest collection of brain illustrations (as well as of other organ systems) attempted in his era. Although lacking the conceptual insight that might derive from a true "comparative" anatomy and an understanding of the relations of different animals, the handsome engravings exemplified the new direction of the 'enlightenment' of the scientific revolution and are discussed in teh context of relevant events of this period.

  3. Schizophrenia, abnormal connection, and brain evolution.

    Science.gov (United States)

    Randall, P L

    1983-03-01

    Abnormalities of functional connection between specialized areas in the human brain may underlie the symptoms which constitute the schizophrenia syndrome. Callosal and intrahemispheric fibres may be equally involved. The clinical emergence of symptoms in the later stages of brain maturation may be dependent on myelination of these fibre groups, both of which have extended myelination cycles. Ontogenetically earlier variants of the same mechanism could theoretically result in dyslexia and the syndromes of Kanner and Gilles de la Tourette. As new and unique extensions of specialized function emerge within the evolving brain, biological trial and error of connection both within and between them may produce individuals possessing phylogenetically advanced abilities, or equally, others possessing a wide range of abnormalities including those which comprise the schizophrenia syndrome. A dormant phenotypic potential for schizophrenia may exist in individuals who never develop symptoms during the course of a lifetime though some of these may become clinically apparent under the influence of various precipitating factors. It is concluded that abnormal functional connection and its normal and "supernormal" counterparts may be natural, essential, and inevitable consequences of brain evolution, and that this may have been so throughout the history of vertebrate brain evolution.

  4. Clinical and cost effectiveness of mechanical support for severe ankle sprains: design of a randomised controlled trial in the emergency department [ISRCTN 37807450

    Directory of Open Access Journals (Sweden)

    Hutton JL

    2005-01-01

    Full Text Available Abstract Background The optimal management for severe sprains (Grades II and III of the lateral ligament complex of the ankle is unclear. The aims of this randomised controlled trial are to estimate (1 the clinical effectiveness of three methods of providing mechanical support to the ankle (below knee cast, Aircast® brace and Bledsoe® boot in comparison to Tubigrip®, and (2 to compare the cost of each strategy, including subsequent health care costs. Methods/design Six hundred and fifty people with a diagnosis of severe sprain are being identified through emergency departments. The study has been designed to complement routine practice in the emergency setting. Outcomes are recovery of mobility (primary outcome and usual activity, residual symptoms and need for further medical, rehabilitation or surgical treatment. Parallel economic and qualitative studies are being conducted to aid interpretation of the results and to evaluate the cost-effectiveness of the interventions. Discussion This paper highlights the design, methods and operational aspects of a clinical trial of acute injury management in the emergency department.

  5. Study on dynamic mechanism model of emergency industry development in China%我国应急产业发展动力机制模型研究

    Institute of Scientific and Technical Information of China (English)

    王建光

    2015-01-01

    调研分析了应急产业有关定义,明确了应急产业的范围;从产业内容、产业发展阶段等角度,分析了应急产业的特点;基于自组织理论和新古典经济理论,结合应急产业特点,建立了应急产业发展动力机制“内切圆”模型。模型中,应急产业的发展动力机制系统包括产业成长的外部动力因素和内部动力因素,其中,外部动力因素包括有市场需求、技术创新、产业政策、产业投资等,内部动力因素包括应急产业内相关企业间的竞争与协作、针对市场失效的产业政策。内部动力因素和外部动力因素之间存在着相互作用,在一定的条件下,外部动力可以与内部动力相互转化。内部和外部动力因素的综合作用,推动应急产业不断发展。%Some conceptions related to emergency industry were investigated .From the view of emergency manage-ment, the definition of emergency industry was analyzed and the scope was cleared .From the view of industry de-velopment phase and content of industry , the features of emergency industry were analyzed .Combining with the characteristics of emergency industry , based on the self-organization theory and the Neo-classical Economics theory , an "inscribed circle"model for development dynamic mechanism of emergency industry was established .In this model , the dynamic mechanism system of emergency industry development includes exogenous dynamic factors and endogenous dynamic factors , the exogenous factors include market demand , technological innovation , industrial policy and industrial investment , and the endogenous factors include the competition and cooperation between enter-prises, and industrial policy aiming at market failure .There is interaction between the endogenous dynamic factors and the exogenous dynamic factors .Under certain conditions , the endogenous dynamic factors and exogenous dy-namic factors can be transformed into each

  6. Arctigenin Treatment Protects Against Brain Damage Through an Anti-inflammatory and Anti-apoptotic Mechanism After Needle Insertion

    OpenAIRE

    Jie Song; Na Li; Xia Yang; Zhong Gao; Liang Kong; Yingjia Yao; Yanan Jiao; Yuhui Yan; Shaoheng Li; Zhenyu Tao; Guan Lian; Jingxian Yang; Tingguo Kang

    2016-01-01

    Convection enhanced delivery (CED) infuses drugs directly into brain tissue. Needle insertion is required and results in a stab wound injury (SWI). Subsequent secondary injury involves the release of inflammatory and apoptotic cytokines, which have dramatic consequences on the integrity of damaged tissue, leading to the evolution of a pericontusional-damaged area minutes to days after in the initial injury. The present study investigated the capacity for arctigenin (ARC) to prevent secondary ...

  7. Arctigenin Treatment Protects against Brain Damage through an Anti-Inflammatory and Anti-Apoptotic Mechanism after Needle Insertion

    OpenAIRE

    Song, Jie; Li, Na; Xia, Yang; Gao, Zhong; Zou, Sa-feng; Kong, Liang; Yao, Ying-Jia; Jiao, Ya-Nan; Yan, Yu-Hui; Li, Shao-Heng; Tao, Zhen-Yu; Lian, Guan; Yang, Jing-xian; Kang, Ting-Guo

    2016-01-01

    Convection enhanced delivery (CED) infuses drugs directly into brain tissue. Needle insertion is required and results in a stab wound injury (SWI). Subsequent secondary injury involves the release of inflammatory and apoptotic cytokines, which have dramatic consequences on the integrity of damaged tissue, leading to the evolution of a pericontusional-damaged area minutes to days after in the initial injury. The present study investigated the capacity for arctigenin (ARC) to prevent secondary ...

  8. Injury to the Preterm Brain and Cerebral Palsy: Clinical Aspects, Molecular Mechanisms, Unanswered Questions, and Future Research Directions

    OpenAIRE

    Babcock, Michael A.; Kostova, Felina V.; Ferriero, Donna M.; Johnston, Michael V.; Brunstrom, Jan E.; Hagberg, Henrik; Maria, Bernard L.

    2009-01-01

    Cerebral palsy will affect nearly 10% of the 60,000 very-low-birth-weight infants born in the United States in the next year, and an even greater percentage will display some form of permanent neurological impairment resulting from injury to the preterm brain. The 2008 Neurobiology of Disease in Children Symposium, held in conjunction with the 37th annual meeting of the Child Neurology Society, aimed to define current knowledge and to develop specific aims for future clinical, translational, ...

  9. Erythropoietin Restores Long-Term Neurocognitive Function Involving Mechanisms of Neuronal Plasticity in a Model of Hyperoxia-Induced Preterm Brain Injury

    Directory of Open Access Journals (Sweden)

    Daniela Hoeber

    2016-01-01

    Full Text Available Cerebral white and grey matter injury is the leading cause of an adverse neurodevelopmental outcome in prematurely born infants. High oxygen concentrations have been shown to contribute to the pathogenesis of neonatal brain damage. Here, we focused on motor-cognitive outcome up to the adolescent and adult age in an experimental model of preterm brain injury. In search of the putative mechanisms of action we evaluated oligodendrocyte degeneration, myelination, and modulation of synaptic plasticity-related molecules. A single dose of erythropoietin (20,000 IU/kg at the onset of hyperoxia (24 hours, 80% oxygen in 6-day-old Wistar rats improved long-lasting neurocognitive development up to the adolescent and adult stage. Analysis of white matter structures revealed a reduction of acute oligodendrocyte degeneration. However, erythropoietin did not influence hypomyelination occurring a few days after injury or long-term microstructural white matter abnormalities detected in adult animals. Erythropoietin administration reverted hyperoxia-induced reduction of neuronal plasticity-related mRNA expression up to four months after injury. Thus, our findings highlight the importance of erythropoietin as a neuroregenerative treatment option in neonatal brain injury, leading to improved memory function in adolescent and adult rats which may be linked to increased neuronal network connectivity.

  10. Erythropoietin Restores Long-Term Neurocognitive Function Involving Mechanisms of Neuronal Plasticity in a Model of Hyperoxia-Induced Preterm Brain Injury.

    Science.gov (United States)

    Hoeber, Daniela; Sifringer, Marco; van de Looij, Yohan; Herz, Josephine; Sizonenko, Stéphane V; Kempe, Karina; Serdar, Meray; Palasz, Joanna; Hadamitzky, Martin; Endesfelder, Stefanie; Fandrey, Joachim; Felderhoff-Müser, Ursula; Bendix, Ivo

    2016-01-01

    Cerebral white and grey matter injury is the leading cause of an adverse neurodevelopmental outcome in prematurely born infants. High oxygen concentrations have been shown to contribute to the pathogenesis of neonatal brain damage. Here, we focused on motor-cognitive outcome up to the adolescent and adult age in an experimental model of preterm brain injury. In search of the putative mechanisms of action we evaluated oligodendrocyte degeneration, myelination, and modulation of synaptic plasticity-related molecules. A single dose of erythropoietin (20,000 IU/kg) at the onset of hyperoxia (24 hours, 80% oxygen) in 6-day-old Wistar rats improved long-lasting neurocognitive development up to the adolescent and adult stage. Analysis of white matter structures revealed a reduction of acute oligodendrocyte degeneration. However, erythropoietin did not influence hypomyelination occurring a few days after injury or long-term microstructural white matter abnormalities detected in adult animals. Erythropoietin administration reverted hyperoxia-induced reduction of neuronal plasticity-related mRNA expression up to four months after injury. Thus, our findings highlight the importance of erythropoietin as a neuroregenerative treatment option in neonatal brain injury, leading to improved memory function in adolescent and adult rats which may be linked to increased neuronal network connectivity. PMID:27493706

  11. Erythropoietin Restores Long-Term Neurocognitive Function Involving Mechanisms of Neuronal Plasticity in a Model of Hyperoxia-Induced Preterm Brain Injury

    Science.gov (United States)

    Sifringer, Marco; van de Looij, Yohan; Herz, Josephine; Sizonenko, Stéphane V.; Kempe, Karina; Palasz, Joanna; Hadamitzky, Martin; Fandrey, Joachim

    2016-01-01

    Cerebral white and grey matter injury is the leading cause of an adverse neurodevelopmental outcome in prematurely born infants. High oxygen concentrations have been shown to contribute to the pathogenesis of neonatal brain damage. Here, we focused on motor-cognitive outcome up to the adolescent and adult age in an experimental model of preterm brain injury. In search of the putative mechanisms of action we evaluated oligodendrocyte degeneration, myelination, and modulation of synaptic plasticity-related molecules. A single dose of erythropoietin (20,000 IU/kg) at the onset of hyperoxia (24 hours, 80% oxygen) in 6-day-old Wistar rats improved long-lasting neurocognitive development up to the adolescent and adult stage. Analysis of white matter structures revealed a reduction of acute oligodendrocyte degeneration. However, erythropoietin did not influence hypomyelination occurring a few days after injury or long-term microstructural white matter abnormalities detected in adult animals. Erythropoietin administration reverted hyperoxia-induced reduction of neuronal plasticity-related mRNA expression up to four months after injury. Thus, our findings highlight the importance of erythropoietin as a neuroregenerative treatment option in neonatal brain injury, leading to improved memory function in adolescent and adult rats which may be linked to increased neuronal network connectivity. PMID:27493706

  12. Pathological relationships involving iron and myelin may constitute a shared mechanism linking various rare and common brain diseases

    Science.gov (United States)

    Heidari, Moones; Gerami, Sam H.; Bassett, Brianna; Graham, Ross M.; Chua, Anita C.G.; Aryal, Ritambhara; House, Michael J.; Collingwood, Joanna F.; Bettencourt, Conceição; Houlden, Henry; Ryten, Mina; Olynyk, John K.; Trinder, Debbie; Johnstone, Daniel M.; Milward, Elizabeth A.

    2016-01-01

    ABSTRACT We previously demonstrated elevated brain iron levels in myelinated structures and associated cells in a hemochromatosis Hfe−/−xTfr2mut mouse model. This was accompanied by altered expression of a group of myelin-related genes, including a suite of genes causatively linked to the rare disease family ‘neurodegeneration with brain iron accumulation’ (NBIA). Expanded data mining and ontological analyses have now identified additional myelin-related transcriptome changes in response to brain iron loading. Concordance between the mouse transcriptome changes and human myelin-related gene expression networks in normal and NBIA basal ganglia testifies to potential clinical relevance. These analyses implicate, among others, genes linked to various rare central hypomyelinating leukodystrophies and peripheral neuropathies including Pelizaeus-Merzbacher-like disease and Charcot-Marie-Tooth disease as well as genes linked to other rare neurological diseases such as Niemann-Pick disease. The findings may help understand interrelationships of iron and myelin in more common conditions such as hemochromatosis, multiple sclerosis and various psychiatric disorders. PMID:27500074

  13. A possible mechanism for PTSD symptoms in patients with traumatic brain injury: The role of central autonomic network disruption

    Directory of Open Access Journals (Sweden)

    John B Williamson

    2013-12-01

    Full Text Available Patients with traumatic brain injuries (TBI often develop Post Traumatic Stress Disorder (PTSD. This syndrome, defined and diagnosed by psychological and behavioral features, is associated with symptoms such as anxiety and anger with an increase of arousal and vigilance, as well as flashbacks and nightmares. Many of these features and symptoms observed in PTSD may be in part the result of altered autonomic nervous system (ANS activity in response to psychological and physical challenges. Brain imaging has documented that TBI often induces white matter damage to pathways associated with the anterior limb of the internal capsule and uncinate fasciculus. Since these white matter structures link neocortical networks with subcortical and limbic structures that regulate autonomic control centers, injury to these pathways may induce a loss of inhibitory control of the ANS. In this review, the autonomic features associated with PTSD are discussed in the context of traumatic brain injury. We posit that TBI induced damage to networks that regulate the ANS increase vulnerability to PTSD. The means by which the vulnerability can be measured and tested are also discussed.

  14. The birth of new neurons in the maternal brain: Hormonal regulation and functional implications.

    Science.gov (United States)

    Leuner, Benedetta; Sabihi, Sara

    2016-04-01

    The maternal brain is remarkably plastic and exhibits multifaceted neural modifications. Neurogenesis has emerged as one of the mechanisms by which the maternal brain exhibits plasticity. This review highlights what is currently known about peripartum-associated changes in adult neurogenesis and the underlying hormonal mechanisms. We also consider the functional consequences of neurogenesis in the peripartum brain and extent to which this process may play a role in maternal care, cognitive function and postpartum mood. Finally, while most work investigating the effects of parenting on adult neurogenesis has focused on mothers, a few studies have examined fathers and these results are also discussed. PMID:26969795

  15. Colistin and tigecycline resistance in carbapenemase-producing Gram-negative bacteria: emerging resistance mechanisms and detection methods.

    Science.gov (United States)

    Osei Sekyere, J; Govinden, U; Bester, L A; Essack, S Y

    2016-09-01

    A literature review was undertaken to ascertain the molecular basis for tigecycline and colistin resistance mechanisms and the experimental basis for the detection and delineation of this resistance particularly in carbapenemase-producing Gram-negative bacteria. Pubmed, Google Scholar and Science Direct were searched with the keywords colistin, tigecycline, resistance mechanisms and detection methods. Trans-complementation and comparative MIC studies, mass spectrometry, chromatography, spectrofluorometry, PCR, qRT-PCR and whole genome sequencing (WGS) were commonly used to determine tigecycline and colistin resistance mechanisms, specifically modifications in the structural and regulatory efflux (acrAB, OqxAB, kpgABC adeABC-FGH-IJK, mexAB-XY-oprJM and soxS, rarA robA, ramRAB marRABC, adeLRS, mexRZ and nfxb) and lipid A (pmrHFIJFKLM, lpxA, lpxC lpxD and mgrB, pmrAB, phoPQ,) genes respectively. Mutations in the ribosomal 16S rRNA operon rrnBC, also yielded resistance to tigecycline through target site modifications. The mcr-1 gene conferring resistance to colistin was identified via WGS, trans-complementation and a murine thigh infection model studies. Common detection methods are mainly antibiotic sensitivity testing with broth microdilution while molecular identification tools are mostly PCR and WGS. Spectrofluorometry, MALDI-TOF MS, micro-array and real-time multiplex PCR hold much promise for the future as new detection tools.

  16. Individualized quantification of brain β-amyloid burden: results of a proof of mechanism phase 0 florbetaben PET trial in patients with Alzheimer's disease and healthy controls

    International Nuclear Information System (INIS)

    Complementing clinical findings with those generated by biomarkers - such as β-amyloid-targeted positron emission tomography (PET) imaging - has been proposed as a means of increasing overall accuracy in the diagnosis of Alzheimer's disease (AD). Florbetaben ([18F]BAY 94-9172) is a novel β-amyloid PET tracer currently in global clinical development. We present the results of a proof of mechanism study in which the diagnostic efficacy, pharmacokinetics, safety and tolerability of florbetaben were assessed. The value of various quantitative parameters derived from the PET scans as potential surrogate markers of cognitive decline was also investigated. Ten patients with mild-moderate probable AD (DSM-IV and NINCDS-ADRDA criteria) and ten age-matched (≥ 55 years) healthy controls (HCs) were administered a single dose of 300 MBq florbetaben, which contained a tracer mass dose of < 5 μg. The 70-90 min post-injection brain PET data were visually analysed by three blinded experts. Quantitative assessment was also performed via MRI-based, anatomical sampling of predefined volumes of interest (VOI) and subsequent calculation of standardized uptake value (SUV) ratios (SUVRs, cerebellar cortex as reference region). Furthermore, single-case, voxelwise analysis was used to calculate individual ''whole brain β-amyloid load''. Visual analysis of the PET data revealed nine of the ten AD, but only one of the ten HC brains to be β-amyloid positive (p = 0.001), with high inter-reader agreement (weighted kappa ≥ 0.88). When compared to HCs, the neocortical SUVRs were significantly higher in the ADs (with descending order of effect size) in frontal cortex, lateral temporal cortex, occipital cortex, anterior and posterior cingulate cortices, and parietal cortex (p = 0.003-0.010). Voxel-based group comparison confirmed these differences. Amongst the PET-derived parameters, the Statistical Parametric Mapping-based whole brain β-amyloid load yielded the closest correlation with

  17. Neuroethics vs neurophysiologically and neuropsychologically uninformed influences in child-rearing, education, emerging hunter-gatherers, and artificial intelligence models of the brain.

    Science.gov (United States)

    Pontius, A A

    1993-04-01

    Potentially negative long-term consequences in four areas are emphasized, if specific neuromaturational, neurophysiological, and neuropsychological facts within a neurodevelopmental and ecological context are neglected in normal functional levels of child development and maturational lag of the frontal lobe system in "Attention Deficit Disorder," in education (reading/writing and arithmetic), in assessment of cognitive functioning in hunter-gatherer populations, specifically modified in the service of their survival, and in constructing computer models of the brain, neglecting consciousness and intentionality as criticized recently by Searle.

  18. The potential mechanism of recombinant human erythropoietin treatment in vivo promoting the cognitive function recovery after traumatic brain injury in mice

    Directory of Open Access Journals (Sweden)

    LEI Ping

    2013-02-01

    Full Text Available Background Inflammation after traumatic brain injury (TBI could exacerbate secondary brain injury, resulting in neuronal apoptosis and neurological deficit. It is confirmed that recombinant human erythropoietin (rhEPO plays an important role in neuroprotection after brain injury. This article discusses the potential mechanism of rhEPO therapy that promotes the neurological function recovery after TBI by observing the changes of neutropils and neuronal apoptosis in the brain tissue of mice after fluid percussion injury (FPI. Methods Adult male C57BL/6 mice were randomly divided into 4 groups: Sham group, TBI group, rhEPO group and normal saline (NS group. On the first, third and seventh days after FPI, 3 mice were randomly taken from each group, the brain tissue of which was obtained. Then, immunohistochemistry was adopted to observe the expression of myeloperoxidase (MPO positive neutrophils and Caspase-3 positive neuronal cells in the hippocampal area. During seventh to eleventh day after FPI, 10 mice of each group were subjected to Morris Water Maze Test and escaping latencies were recorded. Results Compared to Sham group, the number of MPO positive neutrophils began increasing from the first day after FPI (P = 0.000, for all and reached the peak on the third day ( P = 0.000, for all in the TBI group, NS group and rhEPO group, but reduced on the seventh day (P = 0.000, for all; whereas Caspase-3 positive neurons increased significantly 1 d after FPI, peaking on the seventh day. However, the increase of MPO positive cells and Caspase-3 positive neurons in rhEPO group was not obvious. Compared to NS group, MPO positive neutrophils and Caspase-3 positive cells reduced significantly in rhEPO group (P = 0.000, for all 1 to 7 d after FPI in the observed time points. In the Morris Water Maze (MWM, the latency of mice in rhEPO group reduced as compared to the NS group from the third day after FPI (P = 0.013. The differences were statistically

  19. Neuroprotective mechanism of erythropoietin on neonatal brain injury%促红细胞生成素对新生儿脑保护的作用机制

    Institute of Scientific and Technical Information of China (English)

    李浪

    2014-01-01

    Brain injury is a significant cause leading to death of neonates with a considerable variety of complications.Up to now researches have found the neuroprotective actions of erythropoietin (EPO) originally identified as erythropoiesis on neonatal brain injury.EPO has been reported to induce a broad effect in the brain directed to protect and repair neurons damage which are likely to contribute to the improvement in long-term neurological functional outcomes.EPO may provide a new approach for promoting survival and growth in nerve cells and hold great promise for the future treatments of neonatal brain injury.EPO and EPO receptor distribute in defferent parts of brain in fetus and newborns.A fundamental mechanism of EPO-induced neuroprotection is its ability to inhibit apoptosis that EPO and EPO receptor have been shown to modulate three cellular signal transduction pathways.The other neuroprotection mechanisms of EPO-induced include anti-infammatory,neurotrophy,anti-oxidation,angiogenesis,promoting neurogenesis and anti-epilepsy.%新生儿脑损伤可继发多种神经系统并发症,是新生儿死亡的重要原因之一.目前研究发现造血因子促红细胞生成素(EPO)能减轻新生儿脑损伤,对损伤的神经细胞有保护和修复作用,并可能提高远期神经预后.EPO及其受体特异性地分布于胎儿及新生儿脑的不同部位.EPO为神经细胞的存活及发育开辟了新途径,并对新生儿脑损伤的治疗提供了临床应用前景.EPO发挥神经保护作用的主要机制是抗神经细胞凋亡,其在活体内主要通过三条独立的信号通路实现,其他机制还包括抗炎、营养神经、生血管、抗氧化及抗惊厥等.

  20. Adsorption mechanisms of emerging micro-pollutants with a clay mineral: Case of tramadol and doxepine pharmaceutical products.

    Science.gov (United States)

    Thiebault, Thomas; Guégan, Régis; Boussafir, Mohammed

    2015-09-01

    A sodium exchanged smectite clay mineral (Mt) was used as geo-sorbent for the adsorption of tramadol and doxepin: two pharmaceutical products (PPs) defined as emerging pollutants due to their presence at significant concentration in numerous water compartments. The adsorption isotherms for both the temperatures of 20 and 40°C and the derived data determined through the fitting procedure by using Langmuir, Freundlich and Dubinin-Radushkevich equation models explicitly pointed out that the sorption of both tramadol and doxepin is mainly driven by electrostatic interaction. The studied PPs are intercalated in a monolayer arrangement within the interlayer space through a cation exchange in stoichiometric proportion with the Na(+) cations leading to adsorbed PPs amounts that match the cation exchange capacity (CEC) of Mt. Due to their hydrophobic character, additional doxepin molecules could be adsorbed by weak molecular interaction driving to an increase of the adsorbed amount beyond the CEC at low temperature (20°C). The confinement of PPs within the interlayer space of Mt confirms the use of clay minerals as potential material for the wastewater treatment as well as it drives to an amorphous or glassy state, which can find echo in biopharmaceutical applications for a controlled release of PPs.

  1. Diabetic Emergencies

    Science.gov (United States)

    ... Emergencies A-Z Share this! Home » Emergency 101 Diabetic Emergencies It is estimated that more than 20 ... they have it. The best way to prevent diabetic emergencies is to effectively manage the disease through ...

  2. Correlation between emergency treatment time and prognosis of acute traumatic brain injury patients caused by external violence%外部暴力所致急性颅脑创伤预后的相关性因素分析

    Institute of Scientific and Technical Information of China (English)

    杨玲昌

    2015-01-01

    Objective To explore the correlation of prognosis with emergency treatment time,gender,age and GCS score of acute traumatic brain injury patients caused by external violence.Methods 92 acute traumatic brain injury patients caused by external violence were selected.The gender,age,emergency treatment time,post-resuscita-tion GCS and GOS after 5 months were collected and analyzed.The relationship between patients′signs and emergency treatment time and prognosis were analyzed.Results The differences of prognosis between elderly patients and youn-ger patients were statistically significant(χ2 =5.30,P<0.05).The differences of prognosis in patients with different GCS scores were statistically significant(χ2 =11.97,P<0.01).The differences of prognosis in patients with different emergency treatment time were statistically significant(χ2 =15.74,P<0.01).The prognosis with age and emergency treatment time had a significant correlation(P=0.016,0.007).The prognosis of patients with different emergency treatment time had a significant difference(χ2 =28.45,P<0.01).Conclusion The age,post-resuscitation GCS and emergency treatment time are meaningful in predicating patients′mortality and prognosis.The shorter the emer-gency treatment time,the better the prognosis.%目的:探讨外部暴力所致急性颅脑创伤患者现场及院内抢救时间、性别、年龄及格拉斯哥昏迷评分(GCS评分)与预后的相关性。方法选取92例外部暴力所致急性颅脑创伤患者为研究对象,回顾性分析其临床资料。收集患者的性别、年龄、受伤到抢救的时间、入院时 GCS 及5个月后格拉斯哥预后评分(GOS),分析各征象及抢救时间与临床预后的相关性。结果高龄和低龄患者的预后差异有统计学意义(χ2=5.30,P<0.05);GCS评分不同对预后好坏的影响有统计学意义(χ2=11.97,P<0.01);伤后到抢救的时间不同亦对预后好坏产生显著性影响(χ2

  3. The relationship between arterial carbon dioxide tension and end-tidal carbon dioxide tension in intubated adults with traumatic brain injuries who required emergency craniotomies.

    Science.gov (United States)

    Dyer, Brett A; White, William A; Lee, Doohee; Elkins, Laurie; Slayton, Donna J

    2013-01-01

    Anesthetic management of patients who have suffered traumatic brain injuries can be challenging. We investigated the relationship between arterial to end-tidal carbon dioxide partial pressure gradients (Pa-etCO₂) and 3 predictor variables: (1) injury severity score, (2) use of positive end-expiratory pressure, and (3) presence of rib fractures. Using a convenient sampling method, we sampled 56 patients who arrived to the operating room intubated after traumatic brain injuries between 2005 and 2011. Two groups were compared retrospectively: those with Pa-etCO₂ greater than 10 mm Hg (case group) (n = 37) and those with Pa-etCO₂ gradients of 10 mm Hg or less (control group) (n = 19). Descriptive and inferential statistics were employed to identify any differences between the groups. Stepwise regression was also performed. Cross tabulation analysis revealed that injury severity score of 30 or more was a predictor of Pa-etCO₂ gradient. Stepwise regression analysis revealed the presence of rib fracture and body mass index to be significant predictors of Pa-etCO₂ gradient (P < .011). This study identified coexisting conditions in which the patients' Pa-etCO₂ gradients were large. Results showed that injury severity score of 30 or more, the presence of rib fractures, and higher body mass index were statistically significant predictors of Pa-etCO₂ gradients greater than 10 mm Hg. These observations should be considered when evaluating PetCO₂ in conjunction with arterial blood gas analysis to determine optimal ventilation status of these patients.

  4. Brain herniation

    Science.gov (United States)

    ... herniation; Uncal herniation; Subfalcine herniation; Tonsillar herniation; Herniation - brain ... Brain herniation occurs when something inside the skull produces pressure that moves brain tissues. This is most ...

  5. Implementing evidence-based recommended practices for the management of patients with mild traumatic brain injuries in Australian emergency care departments: study protocol for a cluster randomised controlled trial

    Science.gov (United States)

    2014-01-01

    Background Mild head injuries commonly present to emergency departments. The challenges facing clinicians in emergency departments include identifying which patients have traumatic brain injury, and which patients can safely be sent home. Traumatic brain injuries may exist with subtle symptoms or signs, but can still lead to adverse outcomes. Despite the existence of several high quality clinical practice guidelines, internationally and in Australia, research shows inconsistent implementation of these recommendations. The aim of this trial is to test the effectiveness of a targeted, theory- and evidence-informed implementation intervention to increase the uptake of three key clinical recommendations regarding the emergency department management of adult patients (18 years of age or older) who present following mild head injuries (concussion), compared with passive dissemination of these recommendations. The primary objective is to establish whether the intervention is effective in increasing the percentage of patients for which appropriate post-traumatic amnesia screening is performed. Methods/design The design of this study is a cluster randomised trial. We aim to include 34 Australian 24-hour emergency departments, which will be randomised to an intervention or control group. Control group departments will receive a copy of the most recent Australian evidence-based clinical practice guideline on the acute management of patients with mild head injuries. The intervention group will receive an implementation intervention based on an analysis of influencing factors, which include local stakeholder meetings, identification of nursing and medical opinion leaders in each site, a train-the-trainer day and standardised education and interactive workshops delivered by the opinion leaders during a 3 month period of time. Clinical practice outcomes will be collected retrospectively from medical records by independent chart auditors over the 2 month period following

  6. [Mechanisms of the stimulating effect of brain antibodies on the Ca2 current in the neuron membrane].

    Science.gov (United States)

    Solntseva, E I; Pozdniakova, A L; Savich, V; Khorvat, I; Iankovich, B

    1987-11-01

    Antibodies against rat brain microsomes induce a 16 +/- 3% increase in the amplitude of Ca-current (ICa) in snail neurons. Ca-ions block ICa in dose-dependent and potential-dependent manner. Antibodies against microsomes decrease the effectiveness of ICa blockade by Ca-ions: a 85 +/- 10% increase in ICa is observed and I-V curve is normalized. It is suggested that an enhancing effect of antibodies on ICa and the elimination of blocking Ca-effect on ICa are connected with the weakening of divalent cations binding by the anionic groups of calcium channels. PMID:2445395

  7. The Brain Mechanism of Developmental Dyslexia:Evidences From The Brain Image%发展性阅读障碍的脑机制——来自脑成像研究的证据

    Institute of Scientific and Technical Information of China (English)

    杨炀; 毕鸿燕; 王久菊

    2009-01-01

    Developmental dyslexia is a specific learning disability. The cerebral mechanism of development dyslexia is an important topic that has fascinated many researchers. With the introduction of brain imaging in studies of cerebral mechanism of development dyslexia, many achievements have been made. Studies of developmental dyslexia structure image found that development dyslexia showed brain structure abnormal in the parietotemporal region, occipitotemporal cortex, inferior frontal gyrus, and cerebellum et al, manifesting either in one specific area or by the asymmetry of one area; the functional image studies revealed that development dyslexia showed activity abnormal in most regions that proved to display structure abnormality; studies of brain functional connectivity demonstrates that the abnormality of development dyslexia happened not only in the connection between front-back part in one cerebral hemisphere, but also in the connection between the two hemispheres. In addition, some studies indicate Chinese development dyslexia has different brain mechanisms compared to that of alphabetic languages. These findings provide valuable insight for future developmental cerebral mechanisms research and for the expansion of Chinese development dyslexia research.%发展性阅读障碍是一种特殊的学习障碍,发展性阅读障碍的脑机制一直是研究者们关心的一个重要问题.随着脑成像技术的应用,人们在发展性阅读障碍的脑机制研究方面取得了重大进展.脑结构研究发现,发展性阅读障碍者在颞-顶叶、颢.枕叶、额下回、小脑等区域都存在一定的脑结构异常,这些脑结构异常要么表现在某个脑区的结构上,要么表现某个脑区结构的左右不对称性上.脑功能研究发现,发展性阅读障碍者出现脑结构异常的区域也大多表现出脑功能的异常.脑功能连接的研究发现,发展性阅读障碍者脑功能连接的异常不仅涉及到同侧脑区前后部分

  8. Emergence of a Wiener process as a result of the quantum mechanical interaction with a macroscopic medium

    CERN Document Server

    Blasi, R; Namiki, M; Pascazio, S; Blasi, Raffaella; Nakazato, Hiromichi; Namiki, Mikio; Pascazio, Saverio

    1996-01-01

    We analyze a modified version of the Coleman-Hepp model, that is able to take into account energy-exchange processes between the incoming particle and the linear array made up of $N$ spin-1/2 systems. We bring to light the presence of a Wiener dissipative process in the weak-coupling, macroscopic ($N \\rightarrow Hilbert space, the particle undergoes a sort of Brownian motion, while the free Hamiltonian of the spin array serves as a Wiener process. No assumptions are made on the spectrum of the Hamiltonian of the spin system, and no partial trace is computed over its states. The mechanism of appearance of the stochastic process is discussed and contrasted to other noteworthy examples in the literature. The links with van Hove's ``$\\lambda^2 T$ limits are emphasized.

  9. [Mycobacterium tuberculosis mutants with multidrug resistance: history of origin, genetic and molecular mechanisms of resistance, and emerging challenges].

    Science.gov (United States)

    Prozorov, A A; Zaĭchikova, M V; Danilenko, V N

    2012-01-01

    The review summarizes the data on the Mycobacterium tuberculosis mutations that lead to multidrug resistance (MDR) to various antibiotics. MDR strains arose over the past 30 years as a variety of antituberculosis drugs were introduced in medicine, and they largely discount the results of chemotherapy for tuberculosis. The most dangerous of them are strains with extensive drug resistance (XDR), which are resistant to four or five different drugs on average. The molecular mechanisms that make a strain resistant are considered. XDR and MDR strains result from successive and usually independent resistance mutations, which arise in various regions of the mycobacterial genome. In addition, the formation of resistant strains is affected by the phenomenon of tolerance and mycobacterial latency in infected tissues. PMID:22567849

  10. 快速气管切开术在颅脑创伤急救中的应用%Application of Rapid Tracheostomy in Traumatic Brain Injury in Emergency Treatment

    Institute of Scientific and Technical Information of China (English)

    霍利; 吕利英

    2013-01-01

      目的:探讨快速气管切开术在颅脑创伤急救中的应用。方法:38例重型颅脑损伤患者入院后行快速气管切开术。结果:能在短时间内解除呼吸道梗阻,改善通气,纠正低氧血症。结论:快速气管切开术在颅脑创伤急救中为抢救生命及为进一步治疗原发病创造有利时机。%Objective:To explore the application of rapid tracheostomy in traumatic brain injury in emergency treatment.Methods:38 patients with severe craniocerebral injury were given quick tracheotomy.Results:It can relieve airway obstruction,improve ventilation in a short period of time,correct hypoxemia.Conclusion:Rapid tracheostomy in traumatic brain injury first aid for saving lives and further treatment of the primary disease and create the favorable opportunity.

  11. [Longer waiting time and higher mortality in older people with traumatic brain injuries. Mapping of emergency prehospital management and hospital management in Västerbotten].

    Science.gov (United States)

    Holzmann, Martin; Bylund, Per O; Degerfält, Lisa; Carlsson, Axel C; Wändell, Per; Ruge, Toralph

    2015-10-06

    The main purpose was to study the prehospital and early intrahospital treatment of patients with traumatic brain injury (TBI) in the county of Västerbotten 2011-2012. In total, 162 patients were included. The main finding was that a large proportion of TBI patients were older men who fell in the same or from a different level. Older patients had higher mortality and had to wait longer for diagnostic imaging compared to younger patients. Furthermore, most patients were initially relatively unaffected by the injury and around 1/5 of the patients were transported to hospital by private transport. Finally, we observed that most patients were admitted to hospital and computer tomography scan of the head was performed within 4 hours.

  12. Application of optimize the entire pre-hospital emergency care in patients with traumatic brain injury in emergency%院前急救全程优化护理在颅脑损伤患者急救中的应用

    Institute of Scientific and Technical Information of China (English)

    姚菊平; 毛青

    2014-01-01

    Objective To explore the value of optimize the entire pre-hospital emergency care in patients with traumat-ic brain injury in emergency. Methods A total of 132 cases of traumatic brain injury patients were selected for the study, accorded to the time of admission, 62 patients treated from June to December in 2012 were selected as the con-trol group, 70 cases treated from January to July in 2013 were selected as the intervention group, the control group pre-hospital were cared by conventional implementation, while the intervention group to optimize the use of the entire pre-hospital emergency care. Results The intervention group with the pre-hospital emergency GCS and transferred to APS score had no significantly different (P>0.05), while the control group pre-hospital emergency and transferred to GCS and APS scores had significantly different (P0.05),对照组院前急救与转入急诊时GCS和APS评分均有显著差异(P<0.05)。转入急诊时干预组GCS评分显著高于对照组,APS评分显著低于对照组(P<0.05)。两组住院治疗期间预后GOS评价有显著性差异,干预组预后显著优于对照组(P<0.05)。干预组急救反应时间、急诊反应时间、住院时间均显著少于对照组(P<0.05),死亡率显著低于对照组(P<0.05)。干预组患者及家属对院前护理的评价明显高于对照组(P<0.05)。结论院前急救实施全程优化护理可有效提高救治效率缩短患者获得救治时间,提高抢救质量,减低死亡率,缩短住院时间,改善患者预后。

  13. 应激影响脑老化的相关学说与机制%Stress Affecting on Brain Aging:Related Hypothesis and Mechanism

    Institute of Scientific and Technical Information of China (English)

    王铭维; 王培芝; 张忠霞; 耿媛

    2014-01-01

    应激是机体受到各种内外环境因素刺激时的适应性反应,当反应持续时间过久或长期处于激活状态,则会对机体产生不良影响。目前认为,老化与糖皮质激素的过量分泌所致大脑相关区域的损伤相关,这些区域不仅参与认知与情绪,而且与下丘脑-垂体-肾上腺轴控制的其他活动相关。除此之外,皮质醇基础水平的差异性、皮质醇在脑内的可用性、糖皮质激素受体的失衡及大脑本身的易损性、回弹性等都是应激影响脑老化的参与因素。本文将对应激所致正常或非正常老化过程的相关影响机制与学说进行综述。%Stress is an adaptive response when suffering from various internal and external environmental stimulation factors .However ,if this response sustains for more time than necessary or if the body is activated chronically ,harmful effects will be on the body .Now it is considered that aging is related to the injury of correlated brain areas caused by the excessive secretion of glucocorticoid .These areas not only involved in cognition and emotion ,but also with other activities controlled by hypothalamus-pituitary-adrenal axis .In addition ,differences in basal levels of cortisol ,the availability of cortisol in brain ,the imbalance of the glucocorticoid receptor ,the vulnerability and the resilience of the brain itself are all the factors that affect brain aging .This review will give an account of the related mechanism and hypothesis for the stress response that leads to the normal or abnormal brain aging .

  14. Age-dependent neuroplasticity mechanisms in Alzheimer Tg2576 mice following modulation of brain amyloid-β levels.

    Directory of Open Access Journals (Sweden)

    Anna M Lilja

    Full Text Available The objective of this study was to investigate the effects of modulating brain amyloid-β (Aβ levels at different stages of amyloid pathology on synaptic function, inflammatory cell changes and hippocampal neurogenesis, i.e. processes perturbed in Alzheimer's disease (AD. Young (4- to 6-month-old and older (15- to 18-month-old APP(SWE transgenic (Tg2576 mice were treated with the AD candidate drug (+-phenserine for 16 consecutive days. We found significant reductions in insoluble Aβ1-42 levels in the cortices of both young and older transgenic mice, while significant reductions in soluble Aβ1-42 levels and insoluble Aβ1-40 levels were only found in animals aged 15-18 months. Autoradiography binding with the amyloid ligand Pittsburgh Compound B ((3H-PIB revealed a trend for reduced fibrillar Aβ deposition in the brains of older phenserine-treated Tg2576 mice. Phenserine treatment increased cortical synaptophysin levels in younger mice, while decreased interleukin-1β and increased monocyte chemoattractant protein-1 and tumor necrosis factor-alpha levels were detected in the cortices of older mice. The reduction in Aβ1-42 levels was associated with an increased number of bromodeoxyuridine-positive proliferating cells in the hippocampi of both young and older Tg2576 mice. To determine whether the increased cell proliferation was accompanied by increased neuronal production, the endogenous early neuronal marker doublecortin (DCX was examined in the dentate gyrus (DG using immunohistochemical detection. Although no changes in the total number of DCX(+-expressing neurons were detected in the DG in Tg2576 mice at either age following (+-phenserine treatment, dendritic arborization was increased in differentiating neurons in young Tg2576 mice. Collectively, these findings indicate that reducing Aβ1-42 levels in Tg2576 mice at an early pathological stage affects synaptic function by modulating the maturation and plasticity of newborn neurons in

  15. Temperature-dependent growth and emergence of functional leaves: an adaptive mechanism in the seedlings of the western Himalayan plant Podophyllum hexandrum.

    Science.gov (United States)

    Kushwaha, Rekha; Pandey, Subedar; Chanda, Sanjoy; Bhattacharya, Amita; Ahuja, Paramvir Singh

    2008-05-01

    As an adaptive mechanism, hypocotyl dormancy delays emergence of functional leaf until favorable season of growth in Podophyllum hexandrum, an endangered medicinal plant of the western Himalayas. However, upon exposure of the freshly germinated seedlings to favorable temperature (25 degrees C), functional leaves emerged within 20 days. Therefore, we examined regulation mechanisms of growth and development of this alpine plant by temperature under laboratory conditions. The seedlings were exposed to (1) 25 degrees C (temperature prevailing at the time of maximum vegetative growth), (2) 4 degrees C (mean temperature at the onset of winter in its natural habitat), and (3) 10 degrees C (an intermediate temperature). Slackened growth at 4 degrees C was followed by senescence of aerial parts and quiescence of roots and predetermined leaf primordia. Rapid development of leaf primordia at 25 degrees C was associated with increased starch hydrolysis. This was evident from higher alpha-amylase activity and reducing sugars. These parameters decreased on sudden exposure to 4 degrees C. In contrast, the roots (perennating organs) showed a slight increase (1.36-fold) in alpha-amylase activity. Growth and development in seedlings growing at 10 degrees C (temperature less adverse than 4 degrees C) were comparatively faster. The content of reducing sugars and alpha-amylase activity were also higher in all the seedling parts at 10 degrees C as compared to 4 degrees C. This indicated larger requirements for sugar by the seedlings at 10 degrees C. Irrespective of temperature, maximum changes in nitrate and nitrate reductase occurred during the initial 10 days, i.e., when the readily available form of sugars (reducing sugar) was highest. This indicated that a temperature-dependent availability of carbon, but not temperature itself, was an important regulator of uptake and reduction of nitrogen.

  16. Physical mechanism of mind changes and tradeoffs among speed, accuracy, and energy cost in brain decision making: Landscape, flux, and path perspectives

    Science.gov (United States)

    Han, Yan; Kun, Zhang; Jin, Wang

    2016-07-01

    Cognitive behaviors are determined by underlying neural networks. Many brain functions, such as learning and memory, have been successfully described by attractor dynamics. For decision making in the brain, a quantitative description of global attractor landscapes has not yet been completely given. Here, we developed a theoretical framework to quantify the landscape associated with the steady state probability distributions and associated steady state curl flux, measuring the degree of non-equilibrium through the degree of detailed balance breaking for decision making. We quantified the decision-making processes with optimal paths from the undecided attractor states to the decided attractor states, which are identified as basins of attractions, on the landscape. Both landscape and flux determine the kinetic paths and speed. The kinetics and global stability of decision making are explored by quantifying the landscape topography through the barrier heights and the mean first passage time. Our theoretical predictions are in agreement with experimental observations: more errors occur under time pressure. We quantitatively explored two mechanisms of the speed-accuracy tradeoff with speed emphasis and further uncovered the tradeoffs among speed, accuracy, and energy cost. Our results imply that there is an optimal balance among speed, accuracy, and the energy cost in decision making. We uncovered the possible mechanisms of changes of mind and how mind changes improve performance in decision processes. Our landscape approach can help facilitate an understanding of the underlying physical mechanisms of cognitive processes and identify the key factors in the corresponding neural networks. Project supported by the National Natural Science Foundation of China (Grant Nos. 21190040, 91430217, and 11305176).

  17. Physical mechanism of mind changes and tradeoffs among speed, accuracy, and energy cost in brain decision making: Landscape, flux, and path perspectives

    Science.gov (United States)

    Han, Yan; Kun, Zhang; Jin, Wang

    2016-07-01

    Cognitive behaviors are determined by underlying neural networks. Many brain functions, such as learning and memory, have been successfully described by attractor dynamics. For decision making in the brain, a quantitative description of global attractor landscapes has not yet been completely given. Here, we developed a theoretical framework to quantify the landscape associated with the steady state probability distributions and associated steady state curl flux, measuring the degree of non-equilibrium through the degree of detailed balance breaking for decision making. We quantified the decision-making processes with optimal paths from the undecided attractor states to the decided attractor states, which are identified as basins of attractions, on the landscape. Both landscape and flux determine the kinetic paths and speed. The kinetics and global stability of decision making are explored by quantifying the landscape topography through the barrier heights and the mean first passage time. Our theoretical predictions are in agreement with experimental observations: more errors occur under time pressure. We quantitatively explored two mechanisms of the speed-accuracy tradeoff with speed emphasis and further uncovered the tradeoffs among speed, accuracy, and energy cost. Our results imply that there is an optimal balance among speed, accuracy, and the energy cost in decision making. We uncovered the possible mechanisms of changes of mind and how mind changes improve performance in decision processes. Our landscape approach can help facilitate an understanding of the underlying physical mechanisms of cognitive processes and identify the key factors in the corresponding neural networks. Project supported by the National Natural Science Foundation of China (Grant Nos. 21190040, 91430217, and 11305176).

  18. 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.

  19. PEPTIDES INVOLVED IN THE REGULATION OF BRAIN ASYMMETRY IN MAMMALS AND THE POSSIBLE NEUROCHEMICAL MECHANISMS: AN EVOLUTIONARY PERSPECTIVE

    Directory of Open Access Journals (Sweden)

    T.N. Sollertinskaya

    2013-05-01

    Full Text Available In the article the results of the comparative physiological studyng of active drugs of the peptides nature (Semax and Selank have been presented and their role in the compensation of the cognitive functions disturbanced and the brain interhemispheric asymmetry in the ascending row of the mammals. The new data have been obtained that in the insectivores level the influence of the Semax and Selank in the interhemispheric asymmetry regulation has the nonspecific general feature. The differentiation of the drugs effects on the profile behaviour changes appeared as a tendency. At the rodents level the differentiation of the Semax and Selank influence on the motor asymmetry takes place. The regulation effects of the drugs manifested in different ways speking about rats on the right side profil of the behaviour and on the left one and the ambidexters. At the monkey’s level the compensatory effects of the Semax and Selank on the cognitive functions disturbances exertes the distincles different features. It has been established that Semax has the significant cerebroprotective influence on the disturbanced reactions of the selection the side reinforcement. The new data have been established that in rats the ascending influence of the Selank on the new cortex is exerted over the hippocampal structures. The ascending effects of the Semax are obviously exerted over the baso-lateral nuclei of the amygdala and the field CA1 of the hippocampus. The analysis of the data has led us the next conclusions: the formation of the regulatory and compensatory influence of the peptides drugs on the disturbanced brain function is exerted on the common principe of the evolution to the development from diffuse nonspecific influence to the discrete specialization.

  20. On the Construction of China’s Overseas Emergency Assistance Mechanism%我国海外突发事件应急机制构建探析

    Institute of Scientific and Technical Information of China (English)

    孙南翔

    2015-01-01

    随着海外公民数量激增,我国海外公民保护机制面临新挑战。特别是当前我国海外突发事件应急制度还处于起步阶段,不能满足海外公民风险防范和化解的现实需求。我国海外突发事件应急制度的构建应建立在国际法基础上,通过坚持“善意”和“人本”理念,我国应积极在多边或双边层面上加强海外突发事件应急机制的协调,并在明确我国外交部门的救援主体地位下,着力打造起事前预警、事中救援、事后救济的海外突发事件应急机制。%With the increasing number of citizens being abroad,China’s overseas emergency assistance mechanism is confronted with new challenges.In particular,the current overseas protection system is still in its initial stage and cannot meet the demands of substantially preventing and solving the potential risks for oversea Chinese citizens.Therefore,it is of great value for China to construct the overseas assistance mechanism with the recognition of the related principles in international law.On the one hand, the government should promote a multi -lateral or bilateral coordinated mechanism;on the other hand,it should establish an o-verseas emergency response mechanism of advance warning,rescuing immediately as well as reasonable home remedy,with full participation of the diplomatic authorities and under the guidance of concepts of “good faith”and “people -oriented”.