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Sample records for susceptible brain areas

  1. Susceptibility tensor imaging (STI) of the brain.

    Science.gov (United States)

    Li, Wei; Liu, Chunlei; Duong, Timothy Q; van Zijl, Peter C M; Li, Xu

    2017-04-01

    Susceptibility tensor imaging (STI) is a recently developed MRI technique that allows quantitative determination of orientation-independent magnetic susceptibility parameters from the dependence of gradient echo signal phase on the orientation of biological tissues with respect to the main magnetic field. By modeling the magnetic susceptibility of each voxel as a symmetric rank-2 tensor, individual magnetic susceptibility tensor elements as well as the mean magnetic susceptibility and magnetic susceptibility anisotropy can be determined for brain tissues that would still show orientation dependence after conventional scalar-based quantitative susceptibility mapping to remove such dependence. Similar to diffusion tensor imaging, STI allows mapping of brain white matter fiber orientations and reconstruction of 3D white matter pathways using the principal eigenvectors of the susceptibility tensor. In contrast to diffusion anisotropy, the main determinant factor of the susceptibility anisotropy in brain white matter is myelin. Another unique feature of the susceptibility anisotropy of white matter is its sensitivity to gadolinium-based contrast agents. Mechanistically, MRI-observed susceptibility anisotropy is mainly attributed to the highly ordered lipid molecules in the myelin sheath. STI provides a consistent interpretation of the dependence of phase and susceptibility on orientation at multiple scales. This article reviews the key experimental findings and physical theories that led to the development of STI, its practical implementations, and its applications for brain research. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  2. Susceptibility Tensor Imaging (STI) of the Brain

    Science.gov (United States)

    Li, Wei; Liu, Chunlei; Duong, Timothy Q.; van Zijl, Peter C.M.; Li, Xu

    2016-01-01

    Susceptibility tensor imaging (STI) is a recently developed MRI technique that allows quantitative determination of orientation-independent magnetic susceptibility parameters from the dependence of gradient echo signal phase on the orientation of biological tissues with respect to the main magnetic field. By modeling the magnetic susceptibility of each voxel as a symmetric rank-2 tensor, individual magnetic susceptibility tensor elements as well as the mean magnetic susceptibility (MMS) and magnetic susceptibility anisotropy (MSA) can be determined for brain tissues that would still show orientation dependence after conventional scalar-based quantitative susceptibility mapping (QSM) to remove such dependence. Similar to diffusion tensor imaging (DTI), STI allows mapping of brain white matter fiber orientations and reconstruction of 3D white matter pathways using the principal eigenvectors of the susceptibility tensor. In contrast to diffusion anisotropy, the main determinant factor of susceptibility anisotropy in brain white matter is myelin. Another unique feature of susceptibility anisotropy of white matter is its sensitivity to gadolinium-based contrast agents. Mechanistically, MRI-observed susceptibility anisotropy is mainly attributed to the highly ordered lipid molecules in myelin sheath. STI provides a consistent interpretation of the dependence of phase and susceptibility on orientation at multiple scales. This article reviews the key experimental findings and physical theories that led to the development of STI, its practical implementations, and its applications for brain research. PMID:27120169

  3. Susceptibility weighted imaging of the neonatal brain

    International Nuclear Information System (INIS)

    Meoded, A.; Poretti, A.; Northington, F.J.; Tekes, A.; Intrapiromkul, J.; Huisman, T.A.G.M.

    2012-01-01

    Susceptibility weighted imaging (SWI) is a well-established magnetic resonance technique, which is highly sensitive for blood, iron, and calcium depositions in the brain and has been implemented in the routine clinical use in both children and neonates. SWI in neonates might provide valuable additional diagnostic and prognostic information for a wide spectrum of neonatal neurological disorders. To date, there are few articles available on the application of SWI in neonatal neurological disorders. The purpose of this article is to illustrate and describe the characteristic SWI findings in various typical neonatal neurological disorders.

  4. Susceptibility weighted imaging of the neonatal brain

    Energy Technology Data Exchange (ETDEWEB)

    Meoded, A.; Poretti, A. [Division of Pediatric Radiology and Division of Neuroradiology, Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, MD (United States); Northington, F.J. [Division of Neonatology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD (United States); Tekes, A.; Intrapiromkul, J. [Division of Pediatric Radiology and Division of Neuroradiology, Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, MD (United States); Huisman, T.A.G.M., E-mail: thuisma1@jhmi.edu [Division of Pediatric Radiology and Division of Neuroradiology, Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, MD (United States)

    2012-08-15

    Susceptibility weighted imaging (SWI) is a well-established magnetic resonance technique, which is highly sensitive for blood, iron, and calcium depositions in the brain and has been implemented in the routine clinical use in both children and neonates. SWI in neonates might provide valuable additional diagnostic and prognostic information for a wide spectrum of neonatal neurological disorders. To date, there are few articles available on the application of SWI in neonatal neurological disorders. The purpose of this article is to illustrate and describe the characteristic SWI findings in various typical neonatal neurological disorders.

  5. Susceptibility-weighted imaging and quantitative susceptibility mapping in the brain.

    Science.gov (United States)

    Liu, Chunlei; Li, Wei; Tong, Karen A; Yeom, Kristen W; Kuzminski, Samuel

    2015-07-01

    Susceptibility-weighted imaging (SWI) is a magnetic resonance imaging (MRI) technique that enhances image contrast by using the susceptibility differences between tissues. It is created by combining both magnitude and phase in the gradient echo data. SWI is sensitive to both paramagnetic and diamagnetic substances which generate different phase shift in MRI data. SWI images can be displayed as a minimum intensity projection that provides high resolution delineation of the cerebral venous architecture, a feature that is not available in other MRI techniques. As such, SWI has been widely applied to diagnose various venous abnormalities. SWI is especially sensitive to deoxygenated blood and intracranial mineral deposition and, for that reason, has been applied to image various pathologies including intracranial hemorrhage, traumatic brain injury, stroke, neoplasm, and multiple sclerosis. SWI, however, does not provide quantitative measures of magnetic susceptibility. This limitation is currently being addressed with the development of quantitative susceptibility mapping (QSM) and susceptibility tensor imaging (STI). While QSM treats susceptibility as isotropic, STI treats susceptibility as generally anisotropic characterized by a tensor quantity. This article reviews the basic principles of SWI, its clinical and research applications, the mechanisms governing brain susceptibility properties, and its practical implementation, with a focus on brain imaging. © 2014 Wiley Periodicals, Inc.

  6. Susceptibility-Weighted Imaging and Quantitative Susceptibility Mapping in the Brain

    Science.gov (United States)

    Liu, Chunlei; Li, Wei; Tong, Karen A.; Yeom, Kristen W.; Kuzminski, Samuel

    2015-01-01

    Susceptibility-weighted imaging (SWI) is a magnetic resonance imaging (MRI) technique that enhances image contrast by using the susceptibility differences between tissues. It is created by combining both magnitude and phase in the gradient echo data. SWI is sensitive to both paramagnetic and diamagnetic substances which generate different phase shift in MRI data. SWI images can be displayed as a minimum intensity projection that provides high resolution delineation of the cerebral venous architecture, a feature that is not available in other MRI techniques. As such, SWI has been widely applied to diagnose various venous abnormalities. SWI is especially sensitive to deoxygenated blood and intracranial mineral deposition and, for that reason, has been applied to image various pathologies including intracranial hemorrhage, traumatic brain injury, stroke, neoplasm, and multiple sclerosis. SWI, however, does not provide quantitative measures of magnetic susceptibility. This limitation is currently being addressed with the development of quantitative susceptibility mapping (QSM) and susceptibility tensor imaging (STI). While QSM treats susceptibility as isotropic, STI treats susceptibility as generally anisotropic characterized by a tensor quantity. This article reviews the basic principles of SWI, its clinical and research applications, the mechanisms governing brain susceptibility properties, and its practical implementation, with a focus on brain imaging. PMID:25270052

  7. 13 reasons why the brain is susceptible to oxidative stress

    OpenAIRE

    James Nathan Cobley; Maria Luisa Fiorello; Damian Miles Bailey

    2018-01-01

    The human brain consumes 20% of the total basal oxygen (O2) budget to support ATP intensive neuronal activity. Without sufficient O2 to support ATP demands, neuronal activity fails, such that, even transient ischemia is neurodegenerative. While the essentiality of O2 to brain function is clear, how oxidative stress causes neurodegeneration is ambiguous. Ambiguity exists because many of the reasons why the brain is susceptible to oxidative stress remain obscure. Many are erroneously understood...

  8. Effects of tissue susceptibility on brain temperature mapping.

    Science.gov (United States)

    Maudsley, Andrew A; Goryawala, Mohammed Z; Sheriff, Sulaiman

    2017-02-01

    A method for mapping of temperature over a large volume of the brain using volumetric proton MR spectroscopic imaging has been implemented and applied to 150 normal subjects. Magnetic susceptibility-induced frequency shifts in gray- and white-matter regions were measured and included as a correction in the temperature mapping calculation. Additional sources of magnetic susceptibility variations of the individual metabolite resonance frequencies were also observed that reflect the cellular-level organization of the brain metabolites, with the most notable differences being attributed to changes of the N-Acetylaspartate resonance frequency that reflect the intra-axonal distribution and orientation of the white-matter tracts with respect to the applied magnetic field. These metabolite-specific susceptibility effects are also shown to change with age. Results indicate no change of apparent brain temperature with age from 18 to 84 years old, with a trend for increased brain temperature throughout the cerebrum in females relative for males on the order of 0.1°C; slightly increased temperatures in the left hemisphere relative to the right; and a lower temperature of 0.3°C in the cerebellum relative to that of cerebral white-matter. This study presents a novel acquisition method for noninvasive measurement of brain temperature that is of potential value for diagnostic purposes and treatment monitoring, while also demonstrating limitations of the measurement due to the confounding effects of tissue susceptibility variations. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Susceptibility of brain to aerobic, anaerobic, and fungal organisms.

    OpenAIRE

    Costello, G T; Heppe, R; Winn, H R; Scheld, W M; Rodeheaver, G T

    1983-01-01

    The utility of an experimental animal model is dependent on its ability to simulate the actual clinical situation. With a stereotaxic injection procedure, the susceptibility of rat brain to the spectrum of organisms commonly associated with human brain abscess was determined. Two strains of Escherichia coli were more infective than Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus pyogenes. Even between the E. coli strains it was possible to document significant differences in ...

  10. 13 reasons why the brain is susceptible to oxidative stress

    Directory of Open Access Journals (Sweden)

    James Nathan Cobley

    2018-05-01

    Full Text Available The human brain consumes 20% of the total basal oxygen (O2 budget to support ATP intensive neuronal activity. Without sufficient O2 to support ATP demands, neuronal activity fails, such that, even transient ischemia is neurodegenerative. While the essentiality of O2 to brain function is clear, how oxidative stress causes neurodegeneration is ambiguous. Ambiguity exists because many of the reasons why the brain is susceptible to oxidative stress remain obscure. Many are erroneously understood as the deleterious result of adventitious O2 derived free radical and non-radical species generation. To understand how many reasons underpin oxidative stress, one must first re-cast free radical and non-radical species in a positive light because their deliberate generation enables the brain to achieve critical functions (e.g. synaptic plasticity through redox signalling (i.e. positive functionality. Using free radicals and non-radical derivatives to signal sensitises the brain to oxidative stress when redox signalling goes awry (i.e. negative functionality. To advance mechanistic understanding, we rationalise 13 reasons why the brain is susceptible to oxidative stress. Key reasons include inter alia unsaturated lipid enrichment, mitochondria, calcium, glutamate, modest antioxidant defence, redox active transition metals and neurotransmitter auto-oxidation. We review RNA oxidation as an underappreciated cause of oxidative stress. The complex interplay between each reason dictates neuronal susceptibility to oxidative stress in a dynamic context and neural identity dependent manner. Our discourse sets the stage for investigators to interrogate the biochemical basis of oxidative stress in the brain in health and disease.

  11. Identification of seismically susceptible areas in western Himalaya ...

    Indian Academy of Sciences (India)

    This study is an attempt to identify seismically susceptible areas in western Himalaya, using pattern recognition ... a combination of both qualitative and quantita- tive features. .... Three distinct types of zones were identified: S1 was identified as ...

  12. Suitable reference tissues for quantitative susceptibility mapping of the brain.

    Science.gov (United States)

    Straub, Sina; Schneider, Till M; Emmerich, Julian; Freitag, Martin T; Ziener, Christian H; Schlemmer, Heinz-Peter; Ladd, Mark E; Laun, Frederik B

    2017-07-01

    Since quantitative susceptibility mapping (QSM) quantifies magnetic susceptibility relative to a reference value, a suitable reference tissue has to be available to compare different subjects and stages of disease. To find such a suitable reference tissue for QSM of the brain, melanoma patients with and without brain metastases were measured. Twelve reference regions were chosen and assessed for stability of susceptibility values with respect to multiple intra-individual and inter-individual measurements, age, and stage of disease. Cerebrospinal fluid (CSF), the internal capsule and one region in the splenium of the corpus callosum are the regions with the smallest standard deviations of the mean susceptibility value. The mean susceptibility is 0.010 ± 0.014 ppm for CSF in the atrium of the lateral ventricles (csf post ), -0.060 ± 0.019 ppm for the posterior limb of the internal capsule (ci2), and -0.008 ± 0.019 ppm for the splenium of the corpus callosum. csf post and ci2 show nearly no dependence on age or stage of disease, whereas some other regions, e.g., the red nucleus, show moderate dependence on age or disease. The internal capsule and CSF appear to be the most suitable reference regions for QSM of the brain in the melanoma patients studied. Both showed virtually no dependence on age or disease and small variations among patients. Magn Reson Med 78:204-214, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  13. Susceptibility analysis of landslide in Chittagong City Corporation Area, Bangladesh

    Directory of Open Access Journals (Sweden)

    Sourav Das

    2015-06-01

    Full Text Available In Chittagong city, landslide phenomena is the most burning issue which causes great problems to the life and properties and it is increasing day by day and becoming one of the main problems of city life. On 11 June 2007, a massive landslide happened in Chittagong City Corporation (CCC area, a large number of foothill settlements and slums were demolished; more than 90 people died and huge resource destruction took place. It is therefore essential to analyze the landslide susceptibility for CCC area to prepare mitigation strategies as well as assessing the impacts of climate change. To assess community susceptibility of landslide hazard, a landslide susceptibility index map has been prepared using analytical hierarchy process (AHP model based on geographic information system (GIS and remote sensing (RS and its susceptibility is analyzed through community vulnerability assessment tool (CVAT. The major findings of the research are 27% of total CCC area which is susceptible to landslide hazard and whereas 6.5 sq.km areas are found very highly susceptible. The landslide susceptible areas of CCC have also been analyzed in respect of physical, social, economic, environmental and critical facilities and it is found that the overall CCC area is highly susceptible to landslide hazard. So the findings of the research can be utilized to prioritize risk mitigation investments, measures to strengthen the emergency preparedness and response mechanisms for reducing the losses and damages due to future landslide events. DOI: http://dx.doi.org/10.3126/ije.v4i2.12635 International Journal of Environment Vol.4(2 2015: 157-181

  14. Differential susceptibility of brain regions to tributyltin chloride toxicity.

    Science.gov (United States)

    Mitra, Sumonto; Siddiqui, Waseem A; Khandelwal, Shashi

    2015-12-01

    Tributyltin (TBT), a well-known endocrine disruptor, is an omnipresent environmental pollutant and is explicitly used in many industrial applications. Previously we have shown its neurotoxic potential on cerebral cortex of male Wistar rats. As the effect of TBT on other brain regions is not known, we planned this study to evaluate its effect on four brain regions (cerebellum, hippocampus, hypothalamus, and striatum). Four-week-old male Wistar rats were gavaged with a single dose of TBT-chloride (TBTC) (10, 20, and 30 mg/kg) and sacrificed on days 3 and 7, respectively. Effect of TBTC on blood-brain barrier (BBB) permeability and tin (Sn) accumulation were measured. Oxidative stress indexes such as reactive oxygen species (ROS), reduced and oxidized glutathione (GSH/GSSG) ratio, lipid peroxidation, and protein carbonylation were analyzed as they play an imperative role in various neuropathological conditions. Since metal catalyzed reactions are a major source of oxidant generation, levels of essential metals like iron (Fe), zinc (Zn), and calcium (Ca) were estimated. We found that TBTC disrupted BBB and increased Sn accumulation, both of which appear significantly correlated. Altered metal homeostasis and ROS generation accompanied by elevated lipid peroxidation and protein carbonylation indicated oxidative damage which appeared more pronounced in the striatum than in cerebellum, hippocampus, and hypothalamus. This could be associated to the depleted GSH levels in striatum. These results suggest that striatum is more susceptible to TBTC induced oxidative damage as compared with other brain regions under study. © 2014 Wiley Periodicals, Inc.

  15. Spatially explicit shallow landslide susceptibility mapping over large areas

    Science.gov (United States)

    Dino Bellugi; William E. Dietrich; Jonathan Stock; Jim McKean; Brian Kazian; Paul Hargrove

    2011-01-01

    Recent advances in downscaling climate model precipitation predictions now yield spatially explicit patterns of rainfall that could be used to estimate shallow landslide susceptibility over large areas. In California, the United States Geological Survey is exploring community emergency response to the possible effects of a very large simulated storm event and to do so...

  16. Spatially explicit shallow landslide susceptibility mapping over large areas

    Science.gov (United States)

    Bellugi, Dino; Dietrich, William E.; Stock, Jonathan D.; McKean, Jim; Kazian, Brian; Hargrove, Paul

    2011-01-01

    Recent advances in downscaling climate model precipitation predictions now yield spatially explicit patterns of rainfall that could be used to estimate shallow landslide susceptibility over large areas. In California, the United States Geological Survey is exploring community emergency response to the possible effects of a very large simulated storm event and to do so it has generated downscaled precipitation maps for the storm. To predict the corresponding pattern of shallow landslide susceptibility across the state, we have used the model Shalstab (a coupled steady state runoff and infinite slope stability model) which susceptibility spatially explicit estimates of relative potential instability. Such slope stability models that include the effects of subsurface runoff on potentially destabilizing pore pressure evolution require water routing and hence the definition of upslope drainage area to each potential cell. To calculate drainage area efficiently over a large area we developed a parallel framework to scale-up Shalstab and specifically introduce a new efficient parallel drainage area algorithm which produces seamless results. The single seamless shallow landslide susceptibility map for all of California was accomplished in a short run time, and indicates that much larger areas can be efficiently modelled. As landslide maps generally over predict the extent of instability for any given storm. Local empirical data on the fraction of predicted unstable cells that failed for observed rainfall intensity can be used to specify the likely extent of hazard for a given storm. This suggests that campaigns to collect local precipitation data and detailed shallow landslide location maps after major storms could be used to calibrate models and improve their use in hazard assessment for individual storms.

  17. Brain Injury Lesion Imaging Using Preconditioned Quantitative Susceptibility Mapping without Skull Stripping.

    Science.gov (United States)

    Soman, S; Liu, Z; Kim, G; Nemec, U; Holdsworth, S J; Main, K; Lee, B; Kolakowsky-Hayner, S; Selim, M; Furst, A J; Massaband, P; Yesavage, J; Adamson, M M; Spincemallie, P; Moseley, M; Wang, Y

    2018-04-01

    Identifying cerebral microhemorrhage burden can aid in the diagnosis and management of traumatic brain injury, stroke, hypertension, and cerebral amyloid angiopathy. MR imaging susceptibility-based methods are more sensitive than CT for detecting cerebral microhemorrhage, but methods other than quantitative susceptibility mapping provide results that vary with field strength and TE, require additional phase maps to distinguish blood from calcification, and depict cerebral microhemorrhages as bloom artifacts. Quantitative susceptibility mapping provides universal quantification of tissue magnetic property without these constraints but traditionally requires a mask generated by skull-stripping, which can pose challenges at tissue interphases. We evaluated the preconditioned quantitative susceptibility mapping MR imaging method, which does not require skull-stripping, for improved depiction of brain parenchyma and pathology. Fifty-six subjects underwent brain MR imaging with a 3D multiecho gradient recalled echo acquisition. Mask-based quantitative susceptibility mapping images were created using a commonly used mask-based quantitative susceptibility mapping method, and preconditioned quantitative susceptibility images were made using precondition-based total field inversion. All images were reviewed by a neuroradiologist and a radiology resident. Ten subjects (18%), all with traumatic brain injury, demonstrated blood products on 3D gradient recalled echo imaging. All lesions were visible on preconditioned quantitative susceptibility mapping, while 6 were not visible on mask-based quantitative susceptibility mapping. Thirty-one subjects (55%) demonstrated brain parenchyma and/or lesions that were visible on preconditioned quantitative susceptibility mapping but not on mask-based quantitative susceptibility mapping. Six subjects (11%) demonstrated pons artifacts on preconditioned quantitative susceptibility mapping and mask-based quantitative susceptibility mapping

  18. Sex differences in metabolic aging of the brain: insights into female susceptibility to Alzheimer's disease.

    Science.gov (United States)

    Zhao, Liqin; Mao, Zisu; Woody, Sarah K; Brinton, Roberta D

    2016-06-01

    Despite recent advances in the understanding of clinical aspects of sex differences in Alzheimer's disease (AD), the underlying mechanisms, for instance, how sex modifies AD risk and why the female brain is more susceptible to AD, are not clear. The purpose of this study is to elucidate sex disparities in brain aging profiles focusing on 2 major areas-energy and amyloid metabolism-that are most significantly affected in preclinical development of AD. Total RNA isolated from hippocampal tissues of both female and male 129/C57BL/6 mice at ages of 6, 9, 12, or 15 months were comparatively analyzed by custom-designed Taqman low-density arrays for quantitative real-time polymerase chain reaction detection of a total of 182 genes involved in a broad spectrum of biological processes modulating energy production and amyloid homeostasis. Gene expression profiles revealed substantial differences in the trajectory of aging changes between female and male brains. In female brains, 44.2% of genes were significantly changed from 6 months to 9 months and two-thirds showed downregulation. In contrast, in male brains, only 5.4% of genes were significantly altered at this age transition. Subsequent changes in female brains were at a much smaller magnitude, including 10.9% from 9 months to 12 months and 6.1% from 12 months to 15 months. In male brains, most changes occurred from 12 months to 15 months and the majority were upregulated. Furthermore, gene network analysis revealed that clusterin appeared to serve as a link between the overall decreased bioenergetic metabolism and increased amyloid dyshomeostasis associated with the earliest transition in female brains. Together, results from this study indicate that: (1) female and male brains follow profoundly dissimilar trajectories as they age; (2) female brains undergo age-related changes much earlier than male brains; (3) early changes in female brains signal the onset of a hypometabolic phenotype at risk for AD. These

  19. Enhanced brain susceptibility to negative stimuli in adolescents: ERP evidences

    Directory of Open Access Journals (Sweden)

    Jiajin eYuan

    2015-04-01

    Full Text Available Background: previous studies investigated neural substrates of emotional face processing in adolescents and its comparison with adults. As emotional faces elicit more of emotional expression recognition rather than direct emotional responding, it remains undetermined how adolescents are different from adults in brain susceptibility to emotionally stressful stimuli. Methods: Event-Related Potentials were recorded for highly negative (HN, moderately negative (MN and Neutral pictures in 20 adolescents and 20 adults while subjects performed a standard/deviant distinction task by pressing different keys, irrespective of the emotionality of deviant stimuli. Results: Adolescents exhibited more negative amplitudes for HN versus neutral pictures in N1 (100-150ms, P2 (130-190ms, N2 (210-290ms and P3 (360-440ms components. In addition, adolescents showed more negative amplitudes for MN compared to neutral pictures in N1, P2 and N2 components. By contrast, adults exhibited significant emotion effects for HN stimuli in N2 and P3 amplitudes but not in N1 and P2 amplitudes, and they did not exhibit a significant emotion effect for MN stimuli at all these components. In the 210-290ms time interval, the emotion effect for HN stimuli was significant across frontal and central regions in adolescents, while this emotion effect was noticeable only in the central region for adults. Conclusions: Adolescents are more emotionally sensitive to negative stimuli compared to adults, regardless of the emotional intensity of the stimuli, possibly due to the immature prefrontal control system over the limbic emotional inputs during adolescence. Keywords: Event-Related Potentials (ERPs; Adolescence; Emotion intensity; Negative pictures; Emotional Susceptibility

  20. Quantitative Susceptibility Mapping of Human Brain Reflects Spatial Variation in Tissue Composition

    Science.gov (United States)

    Li, Wei; Wu, Bing; Liu, Chunlei

    2011-01-01

    Image phase from gradient echo MRI provides a unique contrast that reflects brain tissue composition variations, such as iron and myelin distribution. Phase imaging is emerging as a powerful tool for the investigation of functional brain anatomy and disease diagnosis. However, the quantitative value of phase is compromised by its nonlocal and orientation dependent properties. There is an increasing need for reliable quantification of magnetic susceptibility, the intrinsic property of tissue. In this study, we developed a novel and accurate susceptibility mapping method that is also phase-wrap insensitive. The proposed susceptibility mapping method utilized two complementary equations: (1) the Fourier relationship of phase and magnetic susceptibility; and (2) the first-order partial derivative of the first equation in the spatial frequency domain. In numerical simulation, this method reconstructed the susceptibility map almost free of streaking artifact. Further, the iterative implementation of this method allowed for high quality reconstruction of susceptibility maps of human brain in vivo. The reconstructed susceptibility map provided excellent contrast of iron-rich deep nuclei and white matter bundles from surrounding tissues. Further, it also revealed anisotropic magnetic susceptibility in brain white matter. Hence, the proposed susceptibility mapping method may provide a powerful tool for the study of brain physiology and pathophysiology. Further elucidation of anisotropic magnetic susceptibility in vivo may allow us to gain more insight into the white matter microarchitectures. PMID:21224002

  1. Quantitative susceptibility mapping of human brain at 3T: a multisite reproducibility study.

    Science.gov (United States)

    Lin, P-Y; Chao, T-C; Wu, M-L

    2015-03-01

    Quantitative susceptibility mapping of the human brain has demonstrated strong potential in examining iron deposition, which may help in investigating possible brain pathology. This study assesses the reproducibility of quantitative susceptibility mapping across different imaging sites. In this study, the susceptibility values of 5 regions of interest in the human brain were measured on 9 healthy subjects following calibration by using phantom experiments. Each of the subjects was imaged 5 times on 1 scanner with the same procedure repeated on 3 different 3T systems so that both within-site and cross-site quantitative susceptibility mapping precision levels could be assessed. Two quantitative susceptibility mapping algorithms, similar in principle, one by using iterative regularization (iterative quantitative susceptibility mapping) and the other with analytic optimal solutions (deterministic quantitative susceptibility mapping), were implemented, and their performances were compared. Results show that while deterministic quantitative susceptibility mapping had nearly 700 times faster computation speed, residual streaking artifacts seem to be more prominent compared with iterative quantitative susceptibility mapping. With quantitative susceptibility mapping, the putamen, globus pallidus, and caudate nucleus showed smaller imprecision on the order of 0.005 ppm, whereas the red nucleus and substantia nigra, closer to the skull base, had a somewhat larger imprecision of approximately 0.01 ppm. Cross-site errors were not significantly larger than within-site errors. Possible sources of estimation errors are discussed. The reproducibility of quantitative susceptibility mapping in the human brain in vivo is regionally dependent, and the precision levels achieved with quantitative susceptibility mapping should allow longitudinal and multisite studies such as aging-related changes in brain tissue magnetic susceptibility. © 2015 by American Journal of Neuroradiology.

  2. Brain Potentials and Personality: A New Look at Stress Susceptibility.

    Science.gov (United States)

    1987-09-01

    disinhibition (Dis) measures a hedonistic , extraverted lifestyle including drinking, parties, sex, and gambling; boredom susceptibility (BS) indicates an...adventure seeking; ES = Experience seeking; Dis = Disinhibition; BS = Boredom susceptibility. 1 14 I N i*5’ Table 4 Correlation of Auditory Evoked...20. aTAS = Thrill and adventure seeking; ES = Experience seeking; Dis = Disinhibition; BS = Boredom susceptibility. < .05. 15 I The present study

  3. Quantitative measurements of brain iron deposition in cirrhotic patients using susceptibility mapping.

    Science.gov (United States)

    Xia, Shuang; Zheng, Gang; Shen, Wen; Liu, Saifeng; Zhang, Long Jiang; Haacke, E Mark; Lu, Guang Ming

    2015-03-01

    Susceptibility-weighted imaging (SWI) has been used to detect micro-bleeds and iron deposits in the brain. However, no reports have been published on the application of SWI in studying iron changes in the brain of cirrhotic patients. To compare the susceptibility of different brain structures in cirrhotic patients with that in healthy controls and to evaluate susceptibility as a potential biomarker and correlate the measured susceptibility and cadaveric brain iron concentration for a variety of brain structures. Forty-three cirrhotic patients (27 men, 16 women; mean age, 50 ± 9 years) and 34 age- and sex-matched healthy controls (22 men, 12 women; mean age, 47 ± 7 years) were included in this retrospective study. Susceptibility was measured in the frontal white matter, basal ganglia, midbrain, and dentate nucleus and compared with results gathered from two postmortem brain studies. Correlation between susceptibility and clinical biomarkers and neuropsychiatric tests scores was calculated. In cirrhotic patients, the susceptibility of left frontal white matter, bilateral caudate head, and right substantia nigra was higher than that in healthy controls (P brain study (r = 0.835, P = 0.01) in eight deep grey matter structures and another in five brain structures (r = 0.900, P = 0.03). The susceptibility of right caudate head (r = 0.402) and left caudate head (r = 0.408) correlated with neuropsychological test scores (both P brain regions appears to reflect neurocognitive changes. © The Foundation Acta Radiologica 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  4. Common genetic variations in cell cycle and DNA repair pathways associated with pediatric brain tumor susceptibility

    DEFF Research Database (Denmark)

    Fahmideh, Maral Adel; Lavebratt, Catharina; Schüz, Joachim

    2016-01-01

    Knowledge on the role of genetic polymorphisms in the etiology of pediatric brain tumors (PBTs) is limited. Therefore, we investigated the association between single nucleotide polymorphisms (SNPs), identified by candidate gene-association studies on adult brain tumors, and PBT risk. The study is...... cycle and DNA repair pathways variations associated with susceptibility to adult brain tumors also seem to be associated with PBT risk, suggesting pediatric and adult brain tumors might share similar etiological pathways....

  5. Using sex differences in the developing brain to identify nodes of influence for seizure susceptibility and epileptogenesis.

    Science.gov (United States)

    Kight, Katherine E; McCarthy, Margaret M

    2014-12-01

    Sexual differentiation of the developing brain organizes the neural architecture differently between males and females, and the main influence on this process is exposure to gonadal steroids during sensitive periods of prenatal and early postnatal development. Many molecular and cellular processes are influenced by steroid hormones in the developing brain, including gene expression, cell birth and death, neurite outgrowth and synaptogenesis, and synaptic activity. Perturbations in these processes can alter neuronal excitability and circuit activity, leading to increased seizure susceptibility and the promotion of pathological processes that constitute epileptogenesis. In this review, we will provide a general overview of sex differences in the early developing brain that may be relevant for altered seizure susceptibility in early life, focusing on limbic areas of the brain. Sex differences that have the potential to alter the progress of epileptogenesis are evident at molecular and cellular levels in the developing brain, and include differences in neuronal excitability, response to environmental insult, and epigenetic control of gene expression. Knowing how these processes differ between the sexes can help us understand fundamental mechanisms underlying gender differences in seizure susceptibility and epileptogenesis. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Perfusion MRI of brain tumours: a comparative study of pseudo-continuous arterial spin labelling and dynamic susceptibility contrast imaging

    Energy Technology Data Exchange (ETDEWEB)

    Jaernum, Hanna; Steffensen, Elena G.; Simonsen, Carsten Wiberg; Jensen, Finn Taagehoej [Aalborg Hospital/Aarhus University Hospital, Department of Radiology, Aalborg (Denmark); Knutsson, Linda [Lund University, Department of Medical Radiation Physics, Lund (Sweden); Fruend, Ernst-Torben [Aalborg Hospital/Aarhus University Hospital, Department of Radiology, Aalborg (Denmark); GE Healthcare - Applied Science Lab Europe, Aalborg (Denmark); Lundbye-Christensen, Soeren [Aalborg Hospital/Aarhus University Hospital, Department of Cardiology, Center for Cardiovascular Research, Aalborg (Denmark); Shankaranarayanan, Ajit [Global Applied Science Lab, GE Healthcare, Menlo Park, CA (United States); Alsop, David C. [Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA (United States); Larsson, Elna-Marie [Aalborg Hospital/Aarhus University Hospital, Department of Radiology, Aalborg (Denmark); Uppsala University Hospital, Department of Radiology, Uppsala (Sweden)

    2010-04-15

    The purpose of this study was to compare the non-invasive 3D pseudo-continuous arterial spin labelling (PC ASL) technique with the clinically established dynamic susceptibility contrast perfusion magnetic resonance imaging (DSC-MRI) for evaluation of brain tumours. A prospective study of 28 patients with contrast-enhancing brain tumours was performed at 3 T using DSC-MRI and PC ASL with whole-brain coverage. The visual qualitative evaluation of signal enhancement in tumour was scored from 0 to 3 (0 = no signal enhancement compared with white matter, 3 = pronounced signal enhancement with equal or higher signal intensity than in grey matter/basal ganglia). The extent of susceptibility artefacts in the tumour was scored from 0 to 2 (0 = no susceptibility artefacts and 2 = extensive susceptibility artefacts (maximum diameter > 2 cm)). A quantitative analysis was performed with normalised tumour blood flow values (ASL nTBF, DSC nTBF): mean value for region of interest (ROI) in an area with maximum signal enhancement/the mean value for ROIs in cerebellum. There was no difference in total visual score for signal enhancement between PC ASL and DSC relative cerebral blood flow (p = 0.12). ASL had a lower susceptibility-artefact score than DSC-MRI (p = 0.03). There was good correlation between DSC nTBF and ASL nTBF values with a correlation coefficient of 0.82. PC ASL is an alternative to DSC-MRI for the evaluation of perfusion in brain tumours. The method has fewer susceptibility artefacts than DSC-MRI and can be used in patients with renal failure because no contrast injection is needed. (orig.)

  7. Bjork-Shiley convexoconcave valves: Susceptibility artifacts at brain MR imaging and mechanical valve fractures

    NARCIS (Netherlands)

    van Gorp, Maarten J.; van der Graaf, Yolanda; de Mol, Bas A. J. M.; Bakker, Chris J. G.; Witkamp, Theo D.; Ramos, Lino M. P.; Mali, Willem P. T. M.

    2004-01-01

    PURPOSE: To assess the relationship between heart valve history and susceptibility artifacts at magnetic resonance (MR) imaging of the brain in patients with Bjork-Shiley convexoconcave (BSCC) valves. MATERIALS AND METHODS: MR images of the brain were obtained in 58 patients with prosthetic heart

  8. A distinct boundary between the higher brain's susceptibility to ischemia and the lower brain's resistance.

    Directory of Open Access Journals (Sweden)

    C Devin Brisson

    Full Text Available Higher brain regions are more susceptible to global ischemia than the brainstem, but is there a gradual increase in vulnerability in the caudal-rostral direction or is there a discrete boundary? We examined the interface between `higher` thalamus and the hypothalamus the using live brain slices where variation in blood flow is not a factor. Whole-cell current clamp recording of 18 thalamic neurons in response to 10 min O2/glucose deprivation (OGD revealed a rapid anoxic depolarization (AD from which thalamic neurons do not recover. Newly acquired neurons could not be patched following AD, confirming significant regional thalamic injury. Coinciding with AD, light transmittance (LT imaging during whole-cell recording showed an elevated LT front that initiated in midline thalamus and that propagated into adjacent hypothalamus. However, hypothalamic neurons patched in paraventricular nucleus (PVN, n= 8 magnocellular and 12 parvocellular neurons and suprachiasmatic nucleus (SCN, n= 18 only slowly depolarized as AD passed through these regions. And with return to control aCSF, hypothalamic neurons repolarized and recovered their input resistance and action potential amplitude. Moreover, newly acquired hypothalamic neurons could be readily patched following exposure to OGD, with resting parameters similar to neurons not previously exposed to OGD. Thalamic susceptibility and hypothalamic resilience were also observed following ouabain exposure which blocks the Na(+/K(+ pump, evoking depolarization similar to OGD in all neuronal types tested. Finally, brief exposure to elevated [K(+]o caused spreading depression (SD, a milder, AD-like event only in thalamic neurons so SD generation is regionally correlated with strong AD. Therefore the thalamus-hypothalamus interface represents a discrete boundary where neuronal vulnerability to ischemia is high in thalamus (like more rostral neocortex, striatum, hippocampus. In contrast hypothalamic neurons are

  9. Large-area landslide susceptibility with optimized slope-units

    Science.gov (United States)

    Alvioli, Massimiliano; Marchesini, Ivan; Reichenbach, Paola; Rossi, Mauro; Ardizzone, Francesca; Fiorucci, Federica; Guzzetti, Fausto

    2017-04-01

    A Slope-Unit (SU) is a type of morphological terrain unit bounded by drainage and divide lines that maximize the within-unit homogeneity and the between-unit heterogeneity across distinct physical and geographical boundaries [1]. Compared to other terrain subdivisions, SU are morphological terrain unit well related to the natural (i.e., geological, geomorphological, hydrological) processes that shape and characterize natural slopes. This makes SU easily recognizable in the field or in topographic base maps, and well suited for environmental and geomorphological analysis, in particular for landslide susceptibility (LS) modelling. An optimal subdivision of an area into a set of SU depends on multiple factors: size and complexity of the study area, quality and resolution of the available terrain elevation data, purpose of the terrain subdivision, scale and resolution of the phenomena for which SU are delineated. We use the recently developed r.slopeunits software [2,3] for the automatic, parametric delineation of SU within the open source GRASS GIS based on terrain elevation data and a small number of user-defined parameters. The software provides subdivisions consisting of SU with different shapes and sizes, as a function of the input parameters. In this work, we describe a procedure for the optimal selection of the user parameters through the production of a large number of realizations of the LS model. We tested the software and the optimization procedure in a 2,000 km2 area in Umbria, Central Italy. For LS zonation we adopt a logistic regression model implemented in an well-known software [4,5], using about 50 independent variables. To select the optimal SU partition for LS zonation, we want to define a metric which is able to quantify simultaneously: (i) slope-unit internal homogeneity (ii) slope-unit external heterogeneity (iii) landslide susceptibility model performance. To this end, we define a comprehensive objective function S, as the product of three

  10. Quantitative susceptibility mapping (QSM) as a means to measure brain iron? A post mortem validation study

    Science.gov (United States)

    Langkammer, Christian; Schweser, Ferdinand; Krebs, Nikolaus; Deistung, Andreas; Goessler, Walter; Scheurer, Eva; Sommer, Karsten; Reishofer, Gernot; Yen, Kathrin; Fazekas, Franz; Ropele, Stefan; Reichenbach, Jürgen R.

    2012-01-01

    Quantitative susceptibility mapping (QSM) is a novel technique which allows determining the bulk magnetic susceptibility distribution of tissue in vivo from gradient echo magnetic resonance phase images. It is commonly assumed that paramagnetic iron is the predominant source of susceptibility variations in gray matter as many studies have reported a reasonable correlation of magnetic susceptibility with brain iron concentrations in vivo. Instead of performing direct comparisons, however, all these studies used the putative iron concentrations reported in the hallmark study by Hallgren and Sourander (1958) for their analysis. Consequently, the extent to which QSM can serve to reliably assess brain iron levels is not yet fully clear. To provide such information we investigated the relation between bulk tissue magnetic susceptibility and brain iron concentration in unfixed (in situ) post mortem brains of 13 subjects using MRI and inductively coupled plasma mass spectrometry. A strong linear correlation between chemically determined iron concentration and bulk magnetic susceptibility was found in gray matter structures (r = 0.84, p < 0.001), whereas the correlation coefficient was much lower in white matter (r = 0.27, p < 0.001). The slope of the overall linear correlation was consistent with theoretical considerations of the magnetism of ferritin supporting that most of the iron in the brain is bound to ferritin proteins. In conclusion, iron is the dominant source of magnetic susceptibility in deep gray matter and can be assessed with QSM. In white matter regions the estimation of iron concentrations by QSM is less accurate and more complex because the counteracting contribution from diamagnetic myelinated neuronal fibers confounds the interpretation. PMID:22634862

  11. Increased susceptibility of dystrophin-deficient brain to mild hypoxia

    International Nuclear Information System (INIS)

    Wallis, T.; Rae, C.; Bubb, W.A.; Head, S.I.

    2002-01-01

    Full text: Duchenne muscular dystrophy is an X-linked disorder resulting from total absence of the 427 kDa protein dystrophin. Dystrophin is normally expressed in the brain mainly in a neuronal subpopulation: cortical pyramidal cells, hippocampal CA1 neurons and cerebellar Purkinje cells. One suggested role for dystrophin is in colocalising mitochondrial creatine kinase with ADP translocase and ATP synthase in mitochondria. Brain tissue slices in the murine model of Duchenne dystrophy, the mdx mouse, have been shown to be more sensitive to hypoxia than control. In this work, we used 13 C NMR to monitor the metabolic response of mdx cortical brain tissue slices to normoxia (95%O 2 /5% CO 2 ) and mild hypoxia (95%air/5% CO 2 ). Under normoxic conditions, mdx cortical slices displayed increased net flux through the Krebs cycle and glutamate/glutamine cycle, consistent with the proposed GABA A lesion which results in decreased inhibitory input. By contrast, mild hypoxia resulted in a significant increase in the total pool size of lactate and decreased net flux of 13 C from [3- 13 C]pyruvate into glutamate C4, GABA C2 and Ala C2, as well as decreased anaplerotic activity as measured by the ratio of Asp C2: Asp C3 label. Mild hypoxia has a significantly greater effect on brain oxidative metabolism in mdx mice, than in control

  12. Increased brain iron deposition is a risk factor for brain atrophy in patients with haemodialysis: a combined study of quantitative susceptibility mapping and whole brain volume analysis.

    Science.gov (United States)

    Chai, Chao; Zhang, Mengjie; Long, Miaomiao; Chu, Zhiqiang; Wang, Tong; Wang, Lijun; Guo, Yu; Yan, Shuo; Haacke, E Mark; Shen, Wen; Xia, Shuang

    2015-08-01

    To explore the correlation between increased brain iron deposition and brain atrophy in patients with haemodialysis and their correlation with clinical biomarkers and neuropsychological test. Forty two patients with haemodialysis and forty one age- and gender-matched healthy controls were recruited in this prospective study. 3D whole brain high resolution T1WI and susceptibility weighted imaging were scanned on a 3 T MRI system. The brain volume was analyzed using voxel-based morphometry (VBM) in patients and to compare with that of healthy controls. Quantitative susceptibility mapping was used to measure and compare the susceptibility of different structures between patients and healthy controls. Correlation analysis was used to investigate the relationship between the brain volume, iron deposition and neuropsychological scores. Stepwise multiple regression analysis was used to explore the effect of clinical biomarkers on the brain volumes in patients. Compared with healthy controls, patients with haemodialysis showed decreased volume of bilateral putamen and left insular lobe (All P brain iron deposition is negatively correlated with the decreased volume of bilateral putamen (P brain iron deposition and dialysis duration was risk factors for brain atrophy in patients with haemodialysis. The decreased gray matter volume of the left insular lobe was correlated with neurocognitive impairment.

  13. Brain susceptibility to oxidative stress in the perinatal period.

    Science.gov (United States)

    Perrone, Serafina; Tataranno, Luisa M; Stazzoni, Gemma; Ramenghi, Luca; Buonocore, Giuseppe

    2015-11-01

    Oxidative stress (OS) occurs at birth in all newborns as a consequence of the hyperoxic challenge due to the transition from the hypoxic intrauterine environment to extrauterine life. Free radical (FRs) sources such as inflammation, hyperoxia, hypoxia, ischaemia-reperfusion, neutrophil and macrophage activation, glutamate and free iron release, all increases the OS during the perinatal period. Newborns, and particularly preterm infants, have reduced antioxidant defences and are not able to counteract the harmful effects of FRs. Energy metabolism is central to life because cells cannot exist without an adequate supply of ATP. Due to its growth, the mammalian brain can be considered as a steady-state system in which ATP production matches ATP utilisation. The developing brain is particularly sensitive to any disturbances in energy generation, and even a short-term interruption can lead to long-lasting and irreversible damage. Whenever energy failure develops, brain damage can occur. Accumulating evidence indicates that OS is implicated in the pathogenesis of many neurological diseases, such as intraventricular haemorrhage, hypoxic-ischaemic encephalopathy and epilepsy.

  14. Restoring susceptibility induced MRI signal loss in rat brain at 9.4 T: A step towards whole brain functional connectivity imaging.

    Directory of Open Access Journals (Sweden)

    Rupeng Li

    Full Text Available The aural cavity magnetic susceptibility artifact leads to significant echo planar imaging (EPI signal dropout in rat deep brain that limits acquisition of functional connectivity fcMRI data. In this study, we provide a method that recovers much of the EPI signal in deep brain. Needle puncture introduction of a liquid-phase fluorocarbon into the middle ear allows acquisition of rat fcMRI data without signal dropout. We demonstrate that with seeds chosen from previously unavailable areas, including the amygdala and the insular cortex, we are able to acquire large scale networks, including the limbic system. This tool allows EPI-based neuroscience and pharmaceutical research in rat brain using fcMRI that was previously not feasible.

  15. Clinical applications of susceptibility weighted MR imaging of the brain - a pictorial review

    International Nuclear Information System (INIS)

    Thomas, Bejoy; Somasundaram, Sivaraman; Thamburaj, Krishnamoorthy; Kesavadas, Chandrasekharan; Kumar Gupta, Arun; Bodhey, Narendra K.; Raman Kapilamoorthy, Tirur

    2008-01-01

    Susceptibility-weighted imaging (SWI) is a novel magnetic resonance (MR) technique that exploits the magnetic susceptibility differences of various tissues, such as blood, iron and calcification. This pictorial review covers many clinical conditions illustrating its usefulness. SWI consists of using both magnitude and phase images from a high-resolution, three-dimensional fully velocity-compensated gradient echo sequence. Phase mask is created from the MR phase images, and multiplying these with the magnitude images increase the conspicuity of the smaller veins and other sources of susceptibility effects, which is depicted using minimal intensity projection (minIP). The phase images are useful in differentiating between diamagnetic and paramagnetic susceptibility effects of calcium and blood, respectively. This unique MR sequence will help in detecting occult low flow vascular lesions, calcification and cerebral microbleed in various pathologic conditions and aids in characterizing tumors and degenerative diseases of the brain. This sequence also can be used to visualize normal brain structures with conspicuity. Susceptibility-weighted imaging is useful in differentiating and characterizing diverse brain pathologies. (orig.)

  16. Possible origins of the susceptibility contrast in the brain. Presidential award proceedings

    International Nuclear Information System (INIS)

    Fukunaga, Masaki; Li, T.Q.; Lee, J.; Matsuura, Eiji; Gelderen, P.V.; Zwart, J.A. de; Merkle, H.; Duyn, J.H.

    2011-01-01

    The magnetic susceptibility contrast derived from high resolution T 2 *-weighted magnetic resonance (MR) imaging at ultra high field strength has been used to reveal laminar contrast in the gray matter (GM) and fiber bundle-like structure in the white matter (WM) of the human brain. This contrast has been attributed to subtle variations in the magnetic properties of brain tissue, which possibly reflect varying iron and myelin content and haemoglobin in the microvasculature. To investigate the origin of this contrast, MRI data from postmortem brain samples were compared with histological staining for iron and myelin. The laminar susceptibility variations in GM strongly correlate with local iron content, which generally co-localized with myelin. On the other hand, fiber bundles in white matter, shows strong susceptibility contrast in the absence of iron while myelin is high. The results suggest that iron contributes significantly to susceptibility contrast across the cortical GM, but myelin is the dominant source of susceptibility in WM bundles. (author)

  17. Susceptibility of various areas of the nervous system of hens to TOCP-induced delayed neuropathy.

    Science.gov (United States)

    Classen, W; Gretener, P; Rauch, M; Weber, E; Krinke, G J

    1996-01-01

    Sensitivity of in-life parameters, biochemical endpoints, and susceptibility of various areas of the chicken nervous system to delayed neuropathy induced by tri-orthocresyl phosphate (TOCP) was assessed. Groups of hens were exposed to a single oral dose of TOCP of 0, 50, 200 or 500 mg/kg and the animals observed for 21 days. Perfusion fixed, paraffin embedded tissue sections were stained with Bodian's silver and Luxol blue and semi-thin epoxy sections with toluidine blue. Sciatic and tibial nerves, lumbosacral, midthoracic, and upper cervical spinal cord, medulla oblongata and cerebellum were examined using a semiquantitative scoring system. In pair-dosed hens inhibition of brain and spinal cord neurotoxic esterase (NTE) and cholinesterase and of plasma and erythrocyte cholinesterases was determined 24 hr and 48 hr after administration. At all dose levels NTE in brain and spinal cord and plasma cholinesterase was inhibited markedly. Quantitative inhibition of NTE was seen also in absence of neuropathy. Ataxia and body weight loss occurred in high-dose animals only, while dose-related neuropathy was seen in the distal tibial nerve, medulla oblongata and cerebellum. Ataxia was correlated best with neuropathy in peripheral nerves while degeneration of nerve fibers in the cerebellum, seen best in mid-longitudinal sections, was the most sensitive histological indicator of TOCP-induced delayed neuropathy. The particular susceptibility of spinocerebellar neurons was recognized long ago, but often has been neglected in delayed neurotoxicity studies and respective guidelines. Optimal sensitivity of toxicity tests is a prerequisite for risk assessment, can be cost efficient, and nowadays should be a main interest of animal welfare in order to reduce animals' suffering. Based on these data, determination of NTE inhibition together with histopathological examination of longitudinal sections of distal tibial nerves, mid-longitudinal sections of rostral cerebellum and cross

  18. Magnetic resonance characteristics and susceptibility weighted imaging of the brain in gadolinium encephalopathy.

    Science.gov (United States)

    Samardzic, Dejan; Thamburaj, Krishnamoorthy

    2015-01-01

    To report the brain imaging features on magnetic resonance imaging (MRI) in inadvertent intrathecal gadolinium administration. A 67-year-old female with gadolinium encephalopathy from inadvertent high dose intrathecal gadolinium administration during an epidural steroid injection was studied with multisequence 3T MRI. T1-weighted imaging shows pseudo-T2 appearance with diffusion of gadolinium into the brain parenchyma, olivary bodies, and membranous labyrinth. Nulling of cerebrospinal fluid (CSF) signal is absent on fluid attenuation recovery (FLAIR). Susceptibility-weighted imaging (SWI) demonstrates features similar to subarachnoid hemorrhage. CT may demonstrate a pseudo-cerebral edema pattern given the high attenuation characteristics of gadolinium. Intrathecal gadolinium demonstrates characteristic imaging features on MRI of the brain and may mimic subarachnoid hemorrhage on susceptibility-weighted imaging. Identifying high dose gadolinium within the CSF spaces on MRI is essential to avoid diagnostic and therapeutic errors. Copyright © 2013 by the American Society of Neuroimaging.

  19. Circuit-wide Transcriptional Profiling Reveals Brain Region-Specific Gene Networks Regulating Depression Susceptibility.

    Science.gov (United States)

    Bagot, Rosemary C; Cates, Hannah M; Purushothaman, Immanuel; Lorsch, Zachary S; Walker, Deena M; Wang, Junshi; Huang, Xiaojie; Schlüter, Oliver M; Maze, Ian; Peña, Catherine J; Heller, Elizabeth A; Issler, Orna; Wang, Minghui; Song, Won-Min; Stein, Jason L; Liu, Xiaochuan; Doyle, Marie A; Scobie, Kimberly N; Sun, Hao Sheng; Neve, Rachael L; Geschwind, Daniel; Dong, Yan; Shen, Li; Zhang, Bin; Nestler, Eric J

    2016-06-01

    Depression is a complex, heterogeneous disorder and a leading contributor to the global burden of disease. Most previous research has focused on individual brain regions and genes contributing to depression. However, emerging evidence in humans and animal models suggests that dysregulated circuit function and gene expression across multiple brain regions drive depressive phenotypes. Here, we performed RNA sequencing on four brain regions from control animals and those susceptible or resilient to chronic social defeat stress at multiple time points. We employed an integrative network biology approach to identify transcriptional networks and key driver genes that regulate susceptibility to depressive-like symptoms. Further, we validated in vivo several key drivers and their associated transcriptional networks that regulate depression susceptibility and confirmed their functional significance at the levels of gene transcription, synaptic regulation, and behavior. Our study reveals novel transcriptional networks that control stress susceptibility and offers fundamentally new leads for antidepressant drug discovery. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Comparison of Magnetic Susceptibility Tensor and Diffusion Tensor of the Brain.

    Science.gov (United States)

    Li, Wei; Liu, Chunlei

    2013-10-01

    Susceptibility tensor imaging (STI) provides a novel approach for noninvasive assessment of the white matter pathways of the brain. Using mouse brain ex vivo , we compared STI with diffusion tensor imaging (DTI), in terms of tensor values, principal tensor values, anisotropy values, and tensor orientations. Despite the completely different biophysical underpinnings, magnetic susceptibility tensors and diffusion tensors show many similarities in the tensor and principal tensor images, for example, the tensors perpendicular to the fiber direction have the highest gray-white matter contrast, and the largest principal tensor is along the fiber direction. Comparison to DTI fractional anisotropy, the susceptibility anisotropy provides much higher sensitivity to the chemical composition of the white matter, especially myelin. The high sensitivity can be further enhanced with the perfusion of ProHance, a gadolinium-based contrast agent. Regarding the tensor orientations, the direction of the largest principal susceptibility tensor agrees with that of diffusion tensors in major white matter fiber bundles. The STI fiber tractography can reconstruct the fiber pathways for the whole corpus callosum and for white matter fiber bundles that are in close contact but in different orientations. There are some differences between susceptibility and diffusion tensor orientations, which are likely due to the limitations in the current STI reconstruction. With the development of more accurate reconstruction methods, STI holds the promise for probing the white matter micro-architectures with more anatomical details and higher chemical sensitivity.

  1. Investigating hyperoxic effects in the rat brain using quantitative susceptibility mapping based on MRI phase.

    Science.gov (United States)

    Hsieh, Meng-Chi; Kuo, Li-Wei; Huang, Yun-An; Chen, Jyh-Horng

    2017-02-01

    To test whether susceptibility imaging can detect microvenous oxygen saturation changes, induced by hyperoxia, in the rat brain. A three-dimensional gradient-echo with a flow compensation sequence was used to acquire T2*-weighted images of rat brains during hyperoxia and normoxia. Quantitative susceptibility mapping (QSM) and QSM-based microvenous oxygenation venography were computed from gradient-echo (GRE) phase images and compared between the two conditions. Pulse oxygen saturation (SpO 2 ) in the cortex was examined and compared with venous oxygen saturation (SvO 2 ) estimated by QSM. Oxygen saturation change calculated by a conventional Δ R2* map was also compared with the ΔSvO 2 estimated by QSM. Susceptibilities of five venous and tissue regions were quantified separately by QSM. Venous susceptibility was reduced by nearly 10%, with an SvO 2 shift of 10% during hyperoxia. A hyperoxic effect, confirmed by SpO 2 measurement, resulted in an SvO 2 increase in the cortex. The ΔSvO 2 between hyperoxia and normoxia was consistent with what was estimated by the Δ R2* map in five regions. These findings suggest that a quantitative susceptibility map is a promising technique for SvO 2 measurement. This method may be useful for quantitatively investigating oxygenation-dependent functional MRI studies. Magn Reson Med 77:592-602, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  2. Mapping Magnetic Susceptibility Anisotropies of White Matter in vivo in the Human Brain at 7 Tesla

    Science.gov (United States)

    Li, Xu; Vikram, Deepti S; Lim, Issel Anne L; Jones, Craig K; Farrell, Jonathan A.D.; van Zijl, Peter C. M.

    2012-01-01

    High-resolution magnetic resonance phase- or frequency- shift images acquired at high field show contrast related to magnetic susceptibility differences between tissues. Such contrast varies with the orientation of the organ in the field, but the development of quantitative susceptibility mapping (QSM) has made it possible to reproducibly image the intrinsic tissue susceptibility contrast. However, recent studies indicate that magnetic susceptibility is anisotropic in brain white matter and, as such, needs to be described by a symmetric second-rank tensor (χ¯¯). To fully determine the elements of this tensor, it would be necessary to acquire frequency data at six or more orientations. Assuming cylindrical symmetry of the susceptibility tensor in myelinated white matter fibers, we propose a simplified method to reconstruct the susceptibility tensor in terms of a mean magnetic susceptibility, MMS = (χ∥ + 2χ⊥)/3 and a magnetic susceptibility anisotropy, MSA = χ∥ − χ⊥, where χ∥ and χ⊥ are susceptibility parallel and perpendicular to the white matter fiber direction, respectively. Computer simulations show that with a practical head rotation angle of around 20°–30°, four head orientations suffice to reproducibly reconstruct the tensor with good accuracy. We tested this approach on whole brain 1×1×1 mm3 frequency data acquired from five healthy subjects at 7 T. The frequency information from phase images collected at four head orientations was combined with the fiber direction information extracted from diffusion tensor imaging (DTI) to map the white matter susceptibility tensor. The MMS and MSA were quantified for regions in several large white matter fiber structures, including the corona radiata, posterior thalamic radiation and corpus callosum. MMS ranged from −0.037 to −0.053 ppm (referenced to CSF being about zero). MSA values could be quantified without the need for a reference and ranged between 0.004 and 0.029 ppm, in line with

  3. Background field removal using a region adaptive kernel for quantitative susceptibility mapping of human brain

    Science.gov (United States)

    Fang, Jinsheng; Bao, Lijun; Li, Xu; van Zijl, Peter C. M.; Chen, Zhong

    2017-08-01

    Background field removal is an important MR phase preprocessing step for quantitative susceptibility mapping (QSM). It separates the local field induced by tissue magnetic susceptibility sources from the background field generated by sources outside a region of interest, e.g. brain, such as air-tissue interface. In the vicinity of air-tissue boundary, e.g. skull and paranasal sinuses, where large susceptibility variations exist, present background field removal methods are usually insufficient and these regions often need to be excluded by brain mask erosion at the expense of losing information of local field and thus susceptibility measures in these regions. In this paper, we propose an extension to the variable-kernel sophisticated harmonic artifact reduction for phase data (V-SHARP) background field removal method using a region adaptive kernel (R-SHARP), in which a scalable spherical Gaussian kernel (SGK) is employed with its kernel radius and weights adjustable according to an energy "functional" reflecting the magnitude of field variation. Such an energy functional is defined in terms of a contour and two fitting functions incorporating regularization terms, from which a curve evolution model in level set formation is derived for energy minimization. We utilize it to detect regions of with a large field gradient caused by strong susceptibility variation. In such regions, the SGK will have a small radius and high weight at the sphere center in a manner adaptive to the voxel energy of the field perturbation. Using the proposed method, the background field generated from external sources can be effectively removed to get a more accurate estimation of the local field and thus of the QSM dipole inversion to map local tissue susceptibility sources. Numerical simulation, phantom and in vivo human brain data demonstrate improved performance of R-SHARP compared to V-SHARP and RESHARP (regularization enabled SHARP) methods, even when the whole paranasal sinus regions

  4. Background field removal using a region adaptive kernel for quantitative susceptibility mapping of human brain.

    Science.gov (United States)

    Fang, Jinsheng; Bao, Lijun; Li, Xu; van Zijl, Peter C M; Chen, Zhong

    2017-08-01

    Background field removal is an important MR phase preprocessing step for quantitative susceptibility mapping (QSM). It separates the local field induced by tissue magnetic susceptibility sources from the background field generated by sources outside a region of interest, e.g. brain, such as air-tissue interface. In the vicinity of air-tissue boundary, e.g. skull and paranasal sinuses, where large susceptibility variations exist, present background field removal methods are usually insufficient and these regions often need to be excluded by brain mask erosion at the expense of losing information of local field and thus susceptibility measures in these regions. In this paper, we propose an extension to the variable-kernel sophisticated harmonic artifact reduction for phase data (V-SHARP) background field removal method using a region adaptive kernel (R-SHARP), in which a scalable spherical Gaussian kernel (SGK) is employed with its kernel radius and weights adjustable according to an energy "functional" reflecting the magnitude of field variation. Such an energy functional is defined in terms of a contour and two fitting functions incorporating regularization terms, from which a curve evolution model in level set formation is derived for energy minimization. We utilize it to detect regions of with a large field gradient caused by strong susceptibility variation. In such regions, the SGK will have a small radius and high weight at the sphere center in a manner adaptive to the voxel energy of the field perturbation. Using the proposed method, the background field generated from external sources can be effectively removed to get a more accurate estimation of the local field and thus of the QSM dipole inversion to map local tissue susceptibility sources. Numerical simulation, phantom and in vivo human brain data demonstrate improved performance of R-SHARP compared to V-SHARP and RESHARP (regularization enabled SHARP) methods, even when the whole paranasal sinus regions

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

    OpenAIRE

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

    2016-01-01

    Dysregulation of brain iron homeostasis is a hallmark of many neurodegenerative diseases and can be associated with oxidative stress. The objective of this study was to investigate brain iron in patients with Neuromyelitis Optica (NMO) using quantitative susceptibility mapping (QSM), a quantitative iron-sensitive MRI technique. 12 clinically confirmed NMO patients (6 female and 6 male; age 35.4y±14.2y) and 12 age- and sex-matched healthy controls (7 female and 5 male; age 33.9±11.3y) underwen...

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

    Directory of Open Access Journals (Sweden)

    Thomas Martin Doring

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

  7. Brain responses to repeated visual experience among low and high sensation seekers: role of boredom susceptibility

    OpenAIRE

    Jiang, Yang; Lianekhammy, Joann; Lawson, Adam; Guo, Chunyan; ynam, Donald; Joseph, Jane E.; Gold, Brian T.; Kelly, Thomas H.

    2009-01-01

    To better understand individual differences in sensation seeking and its components, including boredom susceptibility and experience seeking, we examined brain responses of high and low sensation seekers during repeated visual experience. Individuals scoring in the top and bottom quartiles from a college-aged population on the Brief Sensation-Seeking Scale (BSSS) participated in an event-related potentials (ERPs) experiment. Line drawings of common objects were randomly intermixed and present...

  8. Quantitative Susceptibility Mapping Reveals an Association between Brain Iron Load and Depression Severity

    Directory of Open Access Journals (Sweden)

    Shun Yao

    2017-08-01

    Full Text Available Previous studies have detected abnormal serum ferritin levels in patients with depression; however, the results have been inconsistent. This study used quantitative susceptibility mapping (QSM for the first time to examine brain iron concentration in depressed patients and evaluated whether it is related to severity. We included three groups of age- and gender-matched participants: 30 patients with mild-moderate depression (MD, 14 patients with major depression disorder (MDD and 20 control subjects. All participants underwent MR scans with a 3D gradient-echo sequence reconstructing for QSM and performed the 17-item Hamilton Depression Rating Scale (HDRS test. In MDD, the susceptibility value in the bilateral putamen was significantly increased compared with MD or control subjects. In addition, a significant difference was also observed in the left thalamus in MDD patients compared with controls. However, the susceptibility values did not differ between MD patients and controls. The susceptibility values positively correlated with the severity of depression as indicated by the HDRS scores. Our results provide evidence that brain iron deposition may be associated with depression and may even be a biomarker for investigating the pathophysiological mechanism of depression.

  9. Non-susceptible landslide areas in Italy and in the Mediterranean region

    Science.gov (United States)

    Marchesini, I.; Ardizzone, F.; Alvioli, M.; Rossi, M.; Guzzetti, F.

    2014-08-01

    We used landslide information for 13 study areas in Italy and morphometric information obtained from the 3-arcseconds shuttle radar topography mission digital elevation model (SRTM DEM) to determine areas where landslide susceptibility is expected to be negligible in Italy and in the landmasses surrounding the Mediterranean Sea. The morphometric information consisted of the local terrain slope which was computed in a square 3 × 3-cell moving window, and in the regional relative relief computed in a circular 15 × 15-cell moving window. We tested three different models to classify the "non-susceptible" landslide areas, including a linear model (LNR), a quantile linear model (QLR), and a quantile, non-linear model (QNL). We tested the performance of the three models using independent landslide information presented by the Italian Landslide Inventory (Inventario Fenomeni Franosi in Italia - IFFI). Best results were obtained using the QNL model. The corresponding zonation of non-susceptible landslide areas was intersected in a geographic information system (GIS) with geographical census data for Italy. The result determined that 57.5% of the population of Italy (in 2001) was located in areas where landslide susceptibility is expected to be negligible. We applied the QNL model to the landmasses surrounding the Mediterranean Sea, and we tested the synoptic non-susceptibility zonation using independent landslide information for three study areas in Spain. Results showed that the QNL model was capable of determining where landslide susceptibility is expected to be negligible in the validation areas in Spain. We expect our results to be applicable in similar study areas, facilitating the identification of non-susceptible landslide areas, at the synoptic scale.

  10. Interleukin-1 Receptor in Seizure Susceptibility after Traumatic Injury to the Pediatric Brain.

    Science.gov (United States)

    Semple, Bridgette D; O'Brien, Terence J; Gimlin, Kayleen; Wright, David K; Kim, Shi Eun; Casillas-Espinosa, Pablo M; Webster, Kyria M; Petrou, Steven; Noble-Haeusslein, Linda J

    2017-08-16

    Epilepsy after pediatric traumatic brain injury (TBI) is associated with poor quality of life. This study aimed to characterize post-traumatic epilepsy in a mouse model of pediatric brain injury, and to evaluate the role of interleukin-1 (IL-1) signaling as a target for pharmacological intervention. Male mice received a controlled cortical impact or sham surgery at postnatal day 21, approximating a toddler-aged child. Mice were treated acutely with an IL-1 receptor antagonist (IL-1Ra; 100 mg/kg, s.c.) or vehicle. Spontaneous and evoked seizures were evaluated from video-EEG recordings. Behavioral assays tested for functional outcomes, postmortem analyses assessed neuropathology, and brain atrophy was detected by ex vivo magnetic resonance imaging. At 2 weeks and 3 months post-injury, TBI mice showed an elevated seizure response to the convulsant pentylenetetrazol compared with sham mice, associated with abnormal hippocampal mossy fiber sprouting. A robust increase in IL-1β and IL-1 receptor were detected after TBI. IL-1Ra treatment reduced seizure susceptibility 2 weeks after TBI compared with vehicle, and a reduction in hippocampal astrogliosis. In a chronic study, IL-1Ra-TBI mice showed improved spatial memory at 4 months post-injury. At 5 months, most TBI mice exhibited spontaneous seizures during a 7 d video-EEG recording period. At 6 months, IL-1Ra-TBI mice had fewer evoked seizures compared with vehicle controls, coinciding with greater preservation of cortical tissue. Findings demonstrate this model's utility to delineate mechanisms underlying epileptogenesis after pediatric brain injury, and provide evidence of IL-1 signaling as a mediator of post-traumatic astrogliosis and seizure susceptibility. SIGNIFICANCE STATEMENT Epilepsy is a common cause of morbidity after traumatic brain injury in early childhood. However, a limited understanding of how epilepsy develops, particularly in the immature brain, likely contributes to the lack of efficacious treatments

  11. Differentiation of pyogenic and fungal brain abscesses with susceptibility-weighted MR sequences

    Energy Technology Data Exchange (ETDEWEB)

    Antulov, Ronald; Miletic, Damir [Clinical Hospital Centre Rijeka, Department of Radiology, Rijeka (Croatia); Dolic, Kresimir [Clinical Hospital Centre Split, Department of Radiology, Split (Croatia); Fruehwald-Pallamar, Julia; Thurnher, Majda M. [Medical University Vienna, University Hospital Vienna, Department of Radiology-Subdivision of Neuroradiology and Musculoskeletal Radiology, Vienna (Austria)

    2014-11-15

    Conventional magnetic resonance imaging (MRI) techniques are insufficient to determine the causative agent of brain abscesses. We investigated: (1) the value of susceptibility-weighted MR sequences (SWMRS) in the differentiation of fungal and pyogenic brain abscesses; and (2) the effect of different SWMRS (susceptibility-weighted imaging (SWI) versus venous blood oxygen level dependent (VenoBOLD)) for the detection of specific imaging characteristics of pyogenic brain abscesses. We studied six patients with fungal and ten patients with pyogenic brain abscesses. Imaging characteristics on conventional MRI, diffusion-weighted imaging (DWI) and SWMRS were recorded in all abscesses. All lesions were assessed for the presence of a ''dual-rim sign'' on SWMRS. Homogenously hyperintense lesions on DWI were present in 60 % of patients with pyogenic abscesses, whereas none of the patients with fungal abscesses showed such lesions. On SWMRS, 90 % of patients with pyogenic abscesses and 60 % of patients with fungal abscesses had only lesions with a low-signal-intensity rim. On SWI, the dual-rim sign was apparent in all pyogenic abscesses. None of the fungal abscesses on SWI (P = 0.005) or any of the pyogenic abscesses on VenoBOLD (P = 0.005) were positive for a dual-rim sign. In fungal abscesses, the dual-rim sign is not present but a prominent peripheral rim or central susceptibility effects on SWI will be seen. The appearance of pyogenic abscesses on SWMRS depends on the used sequence, with the dual-rim sign a specific feature of pyogenic brain abscesses on SWI. (orig.)

  12. Task-evoked brain functional magnetic susceptibility mapping by independent component analysis (χICA).

    Science.gov (United States)

    Chen, Zikuan; Calhoun, Vince D

    2016-03-01

    Conventionally, independent component analysis (ICA) is performed on an fMRI magnitude dataset to analyze brain functional mapping (AICA). By solving the inverse problem of fMRI, we can reconstruct the brain magnetic susceptibility (χ) functional states. Upon the reconstructed χ dataspace, we propose an ICA-based brain functional χ mapping method (χICA) to extract task-evoked brain functional map. A complex division algorithm is applied to a timeseries of fMRI phase images to extract temporal phase changes (relative to an OFF-state snapshot). A computed inverse MRI (CIMRI) model is used to reconstruct a 4D brain χ response dataset. χICA is implemented by applying a spatial InfoMax ICA algorithm to the reconstructed 4D χ dataspace. With finger-tapping experiments on a 7T system, the χICA-extracted χ-depicted functional map is similar to the SPM-inferred functional χ map by a spatial correlation of 0.67 ± 0.05. In comparison, the AICA-extracted magnitude-depicted map is correlated with the SPM magnitude map by 0.81 ± 0.05. The understanding of the inferiority of χICA to AICA for task-evoked functional map is an ongoing research topic. For task-evoked brain functional mapping, we compare the data-driven ICA method with the task-correlated SPM method. In particular, we compare χICA with AICA for extracting task-correlated timecourses and functional maps. χICA can extract a χ-depicted task-evoked brain functional map from a reconstructed χ dataspace without the knowledge about brain hemodynamic responses. The χICA-extracted brain functional χ map reveals a bidirectional BOLD response pattern that is unavailable (or different) from AICA. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Low brain ascorbic acid increases susceptibility to seizures in mouse models of decreased brain ascorbic acid transport and Alzheimer's disease.

    Science.gov (United States)

    Warner, Timothy A; Kang, Jing-Qiong; Kennard, John A; Harrison, Fiona E

    2015-02-01

    Seizures are a known co-occurring symptom of Alzheimer's disease, and they can accelerate cognitive and neuropathological dysfunction. Sub-optimal vitamin C (ascorbic acid) deficiency, that is low levels that do not lead the sufferer to present with clinical signs of scurvy (e.g. lethargy, hemorrhage, hyperkeratosis), are easily obtainable with insufficient dietary intake, and may contribute to the oxidative stress environment of both Alzheimer's disease and epilepsy. The purpose of this study was to test whether mice that have diminished brain ascorbic acid in addition to carrying human Alzheimer's disease mutations in the amyloid precursor protein (APP) and presenilin 1 (PSEN1) genes, had altered electrical activity in the brain (electroencephalography; EEG), and were more susceptible to pharmacologically induced seizures. Brain ascorbic acid was decreased in APP/PSEN1 mice by crossing them with sodium vitamin C transporter 2 (SVCT2) heterozygous knockout mice. These mice have an approximately 30% decrease in brain ascorbic acid due to lower levels of SVCT2 that supplies the brain with ASC. SVCT2+/-APP/PSEN1 mice had decreased ascorbic acid and increased oxidative stress in brain, increased mortality, faster seizure onset latency following treatment with kainic acid (10 mg/kg i.p.), and more ictal events following pentylenetetrazol (50 mg/kg i.p.) treatment. Furthermore, we report the entirely novel phenomenon that ascorbic acid deficiency alone increased the severity of kainic acid- and pentylenetetrazol-induced seizures. These data suggest that avoiding ascorbic acid deficiency may be particularly important in populations at increased risk for epilepsy and seizures, such as Alzheimer's disease. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. GIS and statistical analysis for landslide susceptibility mapping in the Daunia area, Italy

    Science.gov (United States)

    Mancini, F.; Ceppi, C.; Ritrovato, G.

    2010-09-01

    This study focuses on landslide susceptibility mapping in the Daunia area (Apulian Apennines, Italy) and achieves this by using a multivariate statistical method and data processing in a Geographical Information System (GIS). The Logistic Regression (hereafter LR) method was chosen to produce a susceptibility map over an area of 130 000 ha where small settlements are historically threatened by landslide phenomena. By means of LR analysis, the tendency to landslide occurrences was, therefore, assessed by relating a landslide inventory (dependent variable) to a series of causal factors (independent variables) which were managed in the GIS, while the statistical analyses were performed by means of the SPSS (Statistical Package for the Social Sciences) software. The LR analysis produced a reliable susceptibility map of the investigated area and the probability level of landslide occurrence was ranked in four classes. The overall performance achieved by the LR analysis was assessed by local comparison between the expected susceptibility and an independent dataset extrapolated from the landslide inventory. Of the samples classified as susceptible to landslide occurrences, 85% correspond to areas where landslide phenomena have actually occurred. In addition, the consideration of the regression coefficients provided by the analysis demonstrated that a major role is played by the "land cover" and "lithology" causal factors in determining the occurrence and distribution of landslide phenomena in the Apulian Apennines.

  15. Outlining precision boundaries among areas with different variability standards using magnetic susceptibility and geomorphic surfaces

    OpenAIRE

    Matias,Sammy S. R.; Marques Júnior,José; Siqueira,Diego S.; Pereira,Gener T.

    2014-01-01

    There is an increasing demand for detailed maps that represent in a simplified way the knowledge of the variability of a particular area or region maps. The objective was to outline precision boundaries among areas with different accuracy variability standards using magnetic susceptibility and geomorphic surfaces. The study was conducted in an area of 110 ha, which identified three compartment landscapes based on the geomorphic surfaces model. To determinate pH, organic matter, phosphorus, po...

  16. Joint eigenvector estimation from mutually anisotropic tensors improves susceptibility tensor imaging of the brain, kidney, and heart.

    Science.gov (United States)

    Dibb, Russell; Liu, Chunlei

    2017-06-01

    To develop a susceptibility-based MRI technique for probing microstructure and fiber architecture of magnetically anisotropic tissues-such as central nervous system white matter, renal tubules, and myocardial fibers-in three dimensions using susceptibility tensor imaging (STI) tools. STI can probe tissue microstructure, but is limited by reconstruction artifacts because of absent phase information outside the tissue and noise. STI accuracy may be improved by estimating a joint eigenvector from mutually anisotropic susceptibility and relaxation tensors. Gradient-recalled echo image data were simulated using a numerical phantom and acquired from the ex vivo mouse brain, kidney, and heart. Susceptibility tensor data were reconstructed using STI, regularized STI, and the proposed algorithm of mutually anisotropic and joint eigenvector STI (MAJESTI). Fiber map and tractography results from each technique were compared with diffusion tensor data. MAJESTI reduced the estimated susceptibility tensor orientation error by 30% in the phantom, 36% in brain white matter, 40% in the inner medulla of the kidney, and 45% in myocardium. This improved the continuity and consistency of susceptibility-based fiber tractography in each tissue. MAJESTI estimation of the susceptibility tensors yields lower orientation errors for susceptibility-based fiber mapping and tractography in the intact brain, kidney, and heart. Magn Reson Med 77:2331-2346, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  17. A network of genes, genetic disorders, and brain areas.

    Directory of Open Access Journals (Sweden)

    Satoru Hayasaka

    Full Text Available The network-based approach has been used to describe the relationship among genes and various phenotypes, producing a network describing complex biological relationships. Such networks can be constructed by aggregating previously reported associations in the literature from various databases. In this work, we applied the network-based approach to investigate how different brain areas are associated to genetic disorders and genes. In particular, a tripartite network with genes, genetic diseases, and brain areas was constructed based on the associations among them reported in the literature through text mining. In the resulting network, a disproportionately large number of gene-disease and disease-brain associations were attributed to a small subset of genes, diseases, and brain areas. Furthermore, a small number of brain areas were found to be associated with a large number of the same genes and diseases. These core brain regions encompassed the areas identified by the previous genome-wide association studies, and suggest potential areas of focus in the future imaging genetics research. The approach outlined in this work demonstrates the utility of the network-based approach in studying genetic effects on the brain.

  18. Malignancy assessment of brain tumours with magnetic resonance spectroscopy and dynamic susceptibility contrast MRI

    Energy Technology Data Exchange (ETDEWEB)

    Fayed, Nicolas; Davila, Jorge; Medrano, Jaime [Diagnostic Radiology Department, Clinica Quiron, Zaragoza (Spain); Olmos, Salvador [Instituto de Investigacion en Ingenieria de Aragon, Zaragoza (Spain)], E-mail: olmos@unizar.es

    2008-09-15

    Magnetic resonance imaging (MRI) is the most common and well-established imaging modality for evaluation of intracerebral neoplasms, but there are still some incompletely solved challenges, such as reliable distinction between high- and low-grade tumours, exact delineation of tumour extension, and discrimination between recurrent tumour and radiation necrosis. The aim of this study was to evaluate the contribution of two MRI techniques to non-invasively estimate brain tumour grade. Twenty-four patients referred to MRI examination were analyzed and diagnosed with single intra-axial brain tumour. Lastly, histopathological analysis was performed to verify tumour type. Ten patients presented low-grade gliomas, while the remaining patients showed high-grade tumours, including glioblastomas in eight cases, isolated metastases in four patients and two cases with anaplastic gliomas. MRI examinations were performed on a 1.5-T scanner (Signa, General Electric). The acquisition protocol included the following sequences: saggital T1-weighted localizer, axial T1- and T2-weighted MRI, single-voxel magnetic resonance spectroscopy (MRS), dynamic susceptibility contrast (DSC) MRI and contrast-enhanced T1-weighted MRI. MRS data was analyzed with standard software provided by the scanner manufacturer. The metabolite ratio with the largest significant difference between tumour grades was the choline/creatine (Ch/Cr) ratio with elevated values in high-grade gliomas and metastases. A Ch/Cr ratio equal or larger than 1.55 predicted malignancy grade with 92% sensitivity and 80% specificity. The area under the ROC curve was 0.92 (CI: 95%; 0.81-1). Regarding to perfusion parameters, relative cerebral blood volume (rCBV) maps were estimated from the MR signal intensity time series during bolus passage with two commercial software packages. Two different regions of interest (ROI) were used to evaluate rCBV: lesion centre and perilesional region. All rCBV values were normalized to CBV in a

  19. Malignancy assessment of brain tumours with magnetic resonance spectroscopy and dynamic susceptibility contrast MRI

    International Nuclear Information System (INIS)

    Fayed, Nicolas; Davila, Jorge; Medrano, Jaime; Olmos, Salvador

    2008-01-01

    Magnetic resonance imaging (MRI) is the most common and well-established imaging modality for evaluation of intracerebral neoplasms, but there are still some incompletely solved challenges, such as reliable distinction between high- and low-grade tumours, exact delineation of tumour extension, and discrimination between recurrent tumour and radiation necrosis. The aim of this study was to evaluate the contribution of two MRI techniques to non-invasively estimate brain tumour grade. Twenty-four patients referred to MRI examination were analyzed and diagnosed with single intra-axial brain tumour. Lastly, histopathological analysis was performed to verify tumour type. Ten patients presented low-grade gliomas, while the remaining patients showed high-grade tumours, including glioblastomas in eight cases, isolated metastases in four patients and two cases with anaplastic gliomas. MRI examinations were performed on a 1.5-T scanner (Signa, General Electric). The acquisition protocol included the following sequences: saggital T1-weighted localizer, axial T1- and T2-weighted MRI, single-voxel magnetic resonance spectroscopy (MRS), dynamic susceptibility contrast (DSC) MRI and contrast-enhanced T1-weighted MRI. MRS data was analyzed with standard software provided by the scanner manufacturer. The metabolite ratio with the largest significant difference between tumour grades was the choline/creatine (Ch/Cr) ratio with elevated values in high-grade gliomas and metastases. A Ch/Cr ratio equal or larger than 1.55 predicted malignancy grade with 92% sensitivity and 80% specificity. The area under the ROC curve was 0.92 (CI: 95%; 0.81-1). Regarding to perfusion parameters, relative cerebral blood volume (rCBV) maps were estimated from the MR signal intensity time series during bolus passage with two commercial software packages. Two different regions of interest (ROI) were used to evaluate rCBV: lesion centre and perilesional region. All rCBV values were normalized to CBV in a

  20. Enhanced Dentate Neurogenesis after Brain Injury Undermines Long-Term Neurogenic Potential and Promotes Seizure Susceptibility

    Directory of Open Access Journals (Sweden)

    Eric J. Neuberger

    2017-09-01

    Full Text Available Hippocampal dentate gyrus is a focus of enhanced neurogenesis and excitability after traumatic brain injury. Increased neurogenesis has been proposed to aid repair of the injured network. Our data show that an early increase in neurogenesis after fluid percussion concussive brain injury is transient and is followed by a persistent decrease compared with age-matched controls. Post-injury changes in neurogenesis paralleled changes in neural precursor cell proliferation and resulted in a long-term decline in neurogenic capacity. Targeted pharmacology to restore post-injury neurogenesis to control levels reversed the long-term decline in neurogenic capacity. Limiting post-injury neurogenesis reduced early increases in dentate excitability and seizure susceptibility. Our results challenge the assumption that increased neurogenesis after brain injury is beneficial and show that early post-traumatic increases in neurogenesis adversely affect long-term outcomes by exhausting neurogenic potential and enhancing epileptogenesis. Treatments aimed at limiting excessive neurogenesis can potentially restore neuroproliferative capacity and limit epilepsy after brain injury.

  1. Assessment of brain metastases by means of dynamic susceptibility contrast enhanced MRI

    International Nuclear Information System (INIS)

    Knopp, M.; Wenz, F.; Debus, J.; Hentrich, H.R.

    2002-01-01

    Full text: To assess if pre therapeutic measurements of regional cerebral blood flow (rCBF) and volume (rCVB) are able to predict the response of brain metastases to radiation therapy and to assess the influence of radiosurgery on rCBF and rCBV on brain metastases and normal surrounding tissue. We examined 25 patients with brain metastases prior to high dose radiosurgery with conventional T1 and T2 weighted MRI and dynamic susceptibility contrast enhanced MRI (DSC MRI). For DSC MRI 55 T2*w GE images of two sections were acquired after bolus administration of 0.1 mmol/kg gadoteridol (ProHance) for the simultaneous measurement of brain feeding arteries and brain tissue. This allowed an absolute quantification of rCBF and rCBV. Follow-up examinations were performed 6 weeks and 3 months after radiotherapy and the acquired perfusion data were related to a 3 point scale of treatment outcome. Radiosurgery was performed by a linear accelerator with a 80% isodose of 18-20 Gv. For treatment planning the heads of the patients were immobilized by a cask mask to avoid head movement. DSC MRI was able to assess perfusion data in all patients. Higher pre therapeutic rCBV seems to predict a poor treatment outcome. After radiosurgery patients with tumor remission and stable disease presented a decrease of rCBV over time regardless of temporary tumor volume increase. Patients with tumor progression at the 3 month followup presented an increase of rCBV. Effects on normal surrounding tissue could not be observed. DSC MRI using Gadoteridol allows the non-invasive assessment of rCBV and rCBF of brain metastases and its changes due to radiosurgery. The method may also be able to predict treatment outcome. Furthermore radiofrequency effects on surrounding unaffected tissue can be monitored. Copyright (2002) Blackwell Science Pty Ltd

  2. Desertification Susceptibility Mapping Using Logistic Regression Analysis in the Djelfa Area, Algeria

    Directory of Open Access Journals (Sweden)

    Farid Djeddaoui

    2017-10-01

    Full Text Available The main goal of this work was to identify the areas that are most susceptible to desertification in a part of the Algerian steppe, and to quantitatively assess the key factors that contribute to this desertification. In total, 139 desertified zones were mapped using field surveys and photo-interpretation. We selected 16 spectral and geomorphic predictive factors, which a priori play a significant role in desertification. They were mainly derived from Landsat 8 imagery and Shuttle Radar Topographic Mission digital elevation model (SRTM DEM. Some factors, such as the topographic position index (TPI and curvature, were used for the first time in this kind of study. For this purpose, we adapted the logistic regression algorithm for desertification susceptibility mapping, which has been widely used for landslide susceptibility mapping. The logistic model was evaluated using the area under the receiver operating characteristic (ROC curve. The model accuracy was 87.8%. We estimated the model uncertainties using a bootstrap method. Our analysis suggests that the predictive model is robust and stable. Our results indicate that land cover factors, including normalized difference vegetation index (NDVI and rangeland classes, play a major role in determining desertification occurrence, while geomorphological factors have a limited impact. The predictive map shows that 44.57% of the area is classified as highly to very highly susceptible to desertification. The developed approach can be used to assess desertification in areas with similar characteristics and to guide possible actions to combat desertification.

  3. IDENTIFICATION OF LANDSLIDES SUSCEPTIBILITY IN THE DOBRIC CATCHMENT AREA USING THE FREQUENCY RATE MODEL

    Directory of Open Access Journals (Sweden)

    ROXANA VĂIDEAN

    2013-11-01

    Full Text Available The landslides susceptibility of the Dobric catchment area (Ilişua river. The territorial geomorfological investigation focuses mainly on the analysis of the present situation, as context of future events occurrence. The previous evolutionary context is secondary in place due also to the particular attention it has received so far. The significance of the knowledge regarding the present events and their evolution is explicit in the attempt to mitigate their impact on the built area and on the resources. The identification of areas characterized by maximum susceptibility in the landslides occurrence is absolutely necessary. The method which makes the identification of these areas possible is none other than the method considering the conditional factors, as well as the spatial distribution of the events that have already occurred. In this regard, the use of the frequency rate model is considered to be ideal.

  4. Stereotactically Standard Areas: Applied Mathematics in the Service of Brain Targeting in Deep Brain Stimulation

    Directory of Open Access Journals (Sweden)

    Ioannis N. Mavridis

    2017-12-01

    Full Text Available The concept of stereotactically standard areas (SSAs within human brain nuclei belongs to the knowledge of the modern field of stereotactic brain microanatomy. These are areas resisting the individual variability of the nuclear location in stereotactic space. This paper summarizes the current knowledge regarding SSAs. A mathematical formula of SSAs was recently invented, allowing for their robust, reproducible, and accurate application to laboratory studies and clinical practice. Thus, SSAs open new doors for the application of stereotactic microanatomy to highly accurate brain targeting, which is mainly useful for minimally invasive neurosurgical procedures, such as deep brain stimulation.

  5. Stereotactically Standard Areas: Applied Mathematics in the Service of Brain Targeting in Deep Brain Stimulation.

    Science.gov (United States)

    Mavridis, Ioannis N

    2017-12-11

    The concept of stereotactically standard areas (SSAs) within human brain nuclei belongs to the knowledge of the modern field of stereotactic brain microanatomy. These are areas resisting the individual variability of the nuclear location in stereotactic space. This paper summarizes the current knowledge regarding SSAs. A mathematical formula of SSAs was recently invented, allowing for their robust, reproducible, and accurate application to laboratory studies and clinical practice. Thus, SSAs open new doors for the application of stereotactic microanatomy to highly accurate brain targeting, which is mainly useful for minimally invasive neurosurgical procedures, such as deep brain stimulation.

  6. Magnetic susceptibility artifacts in a diffuse brain injury and their pathological significance

    International Nuclear Information System (INIS)

    Taguchi, Yoshio; Miyakita, Yasuji; Matsuzawa, Motoshi; Sakakibara, Yohtaro; Takahara, Taro; Yamaguchi, Toshio

    1998-01-01

    In our study, FLAIR images and multishot echo planar imaging T2-weighted images (EPI T2-WI) were used in addition to conventional T1-weighted images, T2-weighted images and T2-weighted sagittal images. In this series we focused our attention on small parenchymatous lesions of a mild or moderate form of diffuse brain injury. These injuries are shown as high intensity areas on T2-weighted images (T2-high intensity lesions) but are not visualized in CT images. This series consisted of 29 patients who were diagnosed with diffuse brain injury and whose CT scans showed a Diffuse Injury I or II. Nineteen patients were studied in an acute or subacute stage. In all but 3 patients, small T2-high intensity lesions were found in the brain parenchyma. In the follow-up study brain edema was suggested because the lesions tended to be absent within 3 months in T2-weighted images and FLAIR. In 10 patients examined during a chronic stage. Small hemorrhages in patients with Diffuse Injury II were shown with variable intensities on the conventional T1- and T2-weighted images, but were visualized with low intensity in an EPI T2-WI. In diffuse brain injuries, small T2-high intensity lesions have been considered to be brain edema or ischemic insults. Our data however, suggested that microhemorrhages associated with brain edema were resent in most of the supratentorial lesions, and in more than a half of the lesions in the corpus callosum and the brain stem. These findings appear similar to contusions, which are defined as traumatic bruises of the neural parenchyma. The use of MRI has increased our understanding of in vivo pathological changes in mild or moderate forms of diffuse brain injury. (K.H.)

  7. Improved superficial brain hemorrhage visualization in susceptibility weighted images by constrained minimum intensity projection

    Science.gov (United States)

    Castro, Marcelo A.; Pham, Dzung L.; Butman, John

    2016-03-01

    Minimum intensity projection is a technique commonly used to display magnetic resonance susceptibility weighted images, allowing the observer to better visualize hemorrhages and vasculature. The technique displays the minimum intensity in a given projection within a thick slab, allowing different connectivity patterns to be easily revealed. Unfortunately, the low signal intensity of the skull within the thick slab can mask superficial tissues near the skull base and other regions. Because superficial microhemorrhages are a common feature of traumatic brain injury, this effect limits the ability to proper diagnose and follow up patients. In order to overcome this limitation, we developed a method to allow minimum intensity projection to properly display superficial tissues adjacent to the skull. Our approach is based on two brain masks, the largest of which includes extracerebral voxels. The analysis of the rind within both masks containing the actual brain boundary allows reclassification of those voxels initially missed in the smaller mask. Morphological operations are applied to guarantee accuracy and topological correctness, and the mean intensity within the mask is assigned to all outer voxels. This prevents bone from dominating superficial regions in the projection, enabling superior visualization of cortical hemorrhages and vessels.

  8. Mean magnetic susceptibility regularized susceptibility tensor imaging (MMSR-STI) for estimating orientations of white matter fibers in human brain.

    Science.gov (United States)

    Li, Xu; van Zijl, Peter C M

    2014-09-01

    An increasing number of studies show that magnetic susceptibility in white matter fibers is anisotropic and may be described by a tensor. However, the limited head rotation possible for in vivo human studies leads to an ill-conditioned inverse problem in susceptibility tensor imaging (STI). Here we suggest the combined use of limiting the susceptibility anisotropy to white matter and imposing morphology constraints on the mean magnetic susceptibility (MMS) for regularizing the STI inverse problem. The proposed MMS regularized STI (MMSR-STI) method was tested using computer simulations and in vivo human data collected at 3T. The fiber orientation estimated from both the STI and MMSR-STI methods was compared to that from diffusion tensor imaging (DTI). Computer simulations show that the MMSR-STI method provides a more accurate estimation of the susceptibility tensor than the conventional STI approach. Similarly, in vivo data show that use of the MMSR-STI method leads to a smaller difference between the fiber orientation estimated from STI and DTI for most selected white matter fibers. The proposed regularization strategy for STI can improve estimation of the susceptibility tensor in white matter. © 2014 Wiley Periodicals, Inc.

  9. Application of logistic regression for landslide susceptibility zoning of Cekmece Area, Istanbul, Turkey

    Science.gov (United States)

    Duman, T. Y.; Can, T.; Gokceoglu, C.; Nefeslioglu, H. A.; Sonmez, H.

    2006-11-01

    As a result of industrialization, throughout the world, cities have been growing rapidly for the last century. One typical example of these growing cities is Istanbul, the population of which is over 10 million. Due to rapid urbanization, new areas suitable for settlement and engineering structures are necessary. The Cekmece area located west of the Istanbul metropolitan area is studied, because the landslide activity is extensive in this area. The purpose of this study is to develop a model that can be used to characterize landslide susceptibility in map form using logistic regression analysis of an extensive landslide database. A database of landslide activity was constructed using both aerial-photography and field studies. About 19.2% of the selected study area is covered by deep-seated landslides. The landslides that occur in the area are primarily located in sandstones with interbedded permeable and impermeable layers such as claystone, siltstone and mudstone. About 31.95% of the total landslide area is located at this unit. To apply logistic regression analyses, a data matrix including 37 variables was constructed. The variables used in the forwards stepwise analyses are different measures of slope, aspect, elevation, stream power index (SPI), plan curvature, profile curvature, geology, geomorphology and relative permeability of lithological units. A total of 25 variables were identified as exerting strong influence on landslide occurrence, and included by the logistic regression equation. Wald statistics values indicate that lithology, SPI and slope are more important than the other parameters in the equation. Beta coefficients of the 25 variables included the logistic regression equation provide a model for landslide susceptibility in the Cekmece area. This model is used to generate a landslide susceptibility map that correctly classified 83.8% of the landslide-prone areas.

  10. Food-Related Odors Activate Dopaminergic Brain Areas

    OpenAIRE

    Agnieszka Sorokowska; Agnieszka Sorokowska; Katherina Schoen; Cornelia Hummel; Pengfei Han; Jonathan Warr; Thomas Hummel

    2017-01-01

    Food-associated cues of different sensory categories have often been shown to be a potent elicitor of cerebral activity in brain reward circuits. Smells influence and modify the hedonic qualities of eating experience, and in contrast to smells not associated with food, perception of food-associated odors may activate dopaminergic brain areas. In this study, we aimed to verify previous findings related to the rewarding value of food-associated odors by means of an fMRI design involving careful...

  11. Combined rock slope stability and shallow landslide susceptibility assessment of the Jasmund cliff area (Rügen Island, Germany

    Directory of Open Access Journals (Sweden)

    A. Günther

    2009-05-01

    Full Text Available In this contribution we evaluated both the structurally-controlled failure susceptibility of the fractured Cretaceous chalk rocks and the topographically-controlled shallow landslide susceptibility of the overlying glacial sediments for the Jasmund cliff area on Rügen Island, Germany. We employed a combined methodology involving spatially distributed kinematical rock slope failure testing with tectonic fabric data, and both physically- and inventory-based shallow landslide susceptibility analysis. The rock slope failure susceptibility model identifies areas of recent cliff collapses, confirming its value in predicting the locations of future failures. The model reveals that toppling is the most important failure type in the Cretaceous chalk rocks of the area. The shallow landslide susceptibility analysis involves a physically-based slope stability evaluation which utilizes material strength and hydraulic conductivity data, and a bivariate landslide susceptibility analysis exploiting landslide inventory data and thematic information on ground conditioning factors. Both models show reasonable success rates when evaluated with the available inventory data, and an attempt was made to combine the individual models to prepare a map displaying both terrain instability and landslide susceptibility. This combination highlights unstable cliff portions lacking discrete landslide areas as well as cliff sections highly affected by past landslide events. Through a spatial integration of the rock slope failure susceptibility model with the combined shallow landslide assessment we produced a comprehensive landslide susceptibility map for the Jasmund cliff area.

  12. Comparative Assessment of Three Nonlinear Approaches for Landslide Susceptibility Mapping in a Coal Mine Area

    Directory of Open Access Journals (Sweden)

    Qiaomei Su

    2017-07-01

    Full Text Available Landslide susceptibility mapping is the first and most important step involved in landslide hazard assessment. The purpose of the present study is to compare three nonlinear approaches for landslide susceptibility mapping and test whether coal mining has a significant impact on landslide occurrence in coal mine areas. Landslide data collected by the Bureau of Land and Resources are represented by the X, Y coordinates of its central point; causative factors were calculated from topographic and geologic maps, as well as satellite imagery. The five-fold cross-validation method was adopted and the landslide/non-landslide datasets were randomly split into a ratio of 80:20. From this, five subsets for 20 times were acquired for training and validating models by GIS Geostatistical analysis methods, and all of the subsets were employed in a spatially balanced sample design. Three landslide models were built using support vector machine (SVM, logistic regression (LR, and artificial neural network (ANN models by selecting the median of the performance measures. Then, the three fitted models were compared using the area under the receiver operating characteristics (ROC curves (AUC and the performance measures. The results show that the prediction accuracies are between 73.43% and 87.45% in the training stage, and 67.16% to 73.13% in the validating stage for the three models. AUCs vary from 0.807 to 0.906 and 0.753 to 0.944 in the two stages, respectively. Additionally, three landslide susceptibility maps were obtained by classifying the range of landslide probabilities into four classes representing low (0–0.02, medium (0.02–0.1, high (0.1–0.85, and very high (0.85–1 probabilities of landslides. For the distributions of landslide and area percentages under different susceptibility standards, the SVM model has more relative balance in the four classes compared to the LR and the ANN models. The result reveals that the SVM model possesses better

  13. Björk-Shiley convexoconcave valves: susceptibility artifacts at brain MR imaging and mechanical valve fractures.

    Science.gov (United States)

    van Gorp, Maarten J; van der Graaf, Yolanda; de Mol, Bas A J M; Bakker, Chris J G; Witkamp, Theo D; Ramos, Lino M P; Mali, Willem P T M

    2004-03-01

    To assess the relationship between heart valve history and susceptibility artifacts at magnetic resonance (MR) imaging of the brain in patients with Björk-Shiley convexoconcave (BSCC) valves. MR images of the brain were obtained in 58 patients with prosthetic heart valves: 20 patients had BSCC valve replacements, and 38 had other types of heart valves. Two experienced neuroradiologists determined the presence or absence of susceptibility artifacts in a consensus reading. Artifacts were defined as characteristic black spots that were visible on T2*-weighted gradient-echo MR images. The statuses of the 20 explanted BSCC valves-specifically, whether they were intact or had an outlet strut fracture (OSF) or a single-leg fracture (SLF)-had been determined earlier. Number of artifacts seen at brain MR imaging was correlated with explanted valve status, and differences were analyzed with nonparametric statistical tests. Significantly more patients with BSCC valves (17 [85%] of 20 patients) than patients with other types of prosthetic valves (18 [47%] of 38 patients) had susceptibility artifacts at MR imaging (P =.005). BSCC valve OSFs were associated with a significantly higher number of artifacts than were intact BSCC valves (P =.01). No significant relationship between SLF and number of artifacts was observed. Susceptibility artifacts at brain MR imaging are not restricted to patients with BSCC valves. These artifacts can be seen on images obtained in patients with various other types of fractured and intact prosthetic heart valves. Copyright RSNA, 2004

  14. Reproducibility of quantitative susceptibility mapping in the brain at two field strengths from two vendors.

    Science.gov (United States)

    Deh, Kofi; Nguyen, Thanh D; Eskreis-Winkler, Sarah; Prince, Martin R; Spincemaille, Pascal; Gauthier, Susan; Kovanlikaya, Ilhami; Zhang, Yan; Wang, Yi

    2015-12-01

    To assess the reproducibility of brain quantitative susceptibility mapping (QSM) in healthy subjects and in patients with multiple sclerosis (MS) on 1.5 and 3T scanners from two vendors. Ten healthy volunteers and 10 patients were scanned twice on a 3T scanner from one vendor. The healthy volunteers were also scanned on a 1.5T scanner from the same vendor and on a 3T scanner from a second vendor. Similar imaging parameters were used for all scans. QSM images were reconstructed using a recently developed nonlinear morphology-enabled dipole inversion (MEDI) algorithm with L1 regularization. Region-of-interest (ROI) measurements were obtained for 20 major brain structures. Reproducibility was evaluated with voxel-wise and ROI-based Bland-Altman plots and linear correlation analysis. ROI-based QSM measurements showed excellent correlation between all repeated scans (correlation coefficient R ≥ 0.97), with a mean difference of less than 1.24 ppb (healthy subjects) and 4.15 ppb (patients), and 95% limits of agreements of within -25.5 to 25.0 ppb (healthy subjects) and -35.8 to 27.6 ppb (patients). Voxel-based QSM measurements had a good correlation (0.64 ≤ R ≤ 0.88) and limits of agreements of -60 to 60 ppb or less. Brain QSM measurements have good interscanner and same-scanner reproducibility for healthy and MS subjects, respectively, on the systems evaluated in this study. © 2015 Wiley Periodicals, Inc.

  15. Prominent hypointense veins on susceptibility weighted image in the cat brain with acute infarction: DWI, SWI, and PWI.

    Science.gov (United States)

    Kim, Yong-Woo; Kim, Hak Jin; Choi, Seon Hee; Kim, Dong Chan

    2014-10-01

    The multiple prominent hypointense veins on susceptibility-weighted imaging (SWI) have been found in the ischemic territory of patients with acute ischemic stroke. Venous side is the unknown area in the hemodynamics of brain infarction. To evaluate the venous aspect in acute brain infarction through an animal study. The acute infarction in cat brains was induced with a bolus infusion of 0.25 mL of triolein through one side of the common carotid artery. The magnetic resonance (MR) images, including diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC) map, SW, and perfusion-weighted (PWI) images, were obtained serially at 2 h (n = 17), 1 day (n = 11), and 4 days (n = 4) after triolein infusion. The obtained MR images were evaluated qualitatively and quantitatively. For qualitative assessment, the signal intensity of the serial MR images was evaluated. The presence or absence and the location with serial changes of infarction were identified on DWI and ADC map images. The presence or absence of prominent hypointense veins and the serial changes of cortical veins were also evaluated on SWI. Quantitative assessment was performed by comparing the relative cerebral blood volume (rCBV), cerebral blood flow (rCBF), and mean transit times (MTT) of the lesions with those of the contralateral normal side calculated on PWI. The serial changes of rCBV, rCBF, and MTT ratio were also evaluated. Acute infarction in the first and second medial gyrus of lesion hemisphere was found by qualitative evaluation of DWI and ADC map images. On the serial evaluation of SWI, the cortical veins of cat brain with infarction were obscured at 2 h and then re-appeared at 1 day. The hemorrhage transformation and prominent hypointense veins were seen at 4 days on SWI. The quantitative evaluation revealed increased MTT ratios and decreased rCBV and rCBF ratios on PWIs in the acute infarction of cat brain. The prominent hypointense veins on SWI were seen in the half of the acute

  16. Contrast enhanced susceptibility weighted imaging (CE-SWI) of the mouse brain using ultrasmall superparamagnetic ironoxide particles (USPIO)

    International Nuclear Information System (INIS)

    Hamans, B.C.; Heerschap, A.; Barth, M.; Leenders, W.P.

    2006-01-01

    Susceptibility weighted imaging (SWI) has been introduced as a novel approach to visualize the venous vasculature in the human brain. With SWI, small veins in the brain are depicted based on the susceptibility difference between deoxyhaemoglobin in the veins and surrounding tissue, which is further enhanced by the use of MR phase information. In this study we applied SWI in the mouse brain using an exogenous iron-based blood-pool contrast agent, with the aims of further enhancing the susceptibility effect and allowing the visualization of individual veins and arteries. Contrast enhanced (CE-) SWI of the brain was performed on healthy mice and mice carrying intracerebral glioma xenografts. This study demonstrates that detailed vascular information in the mouse brain can be obtained by using CE-SWI and is substantially enhanced compared to native SWI (i.e. without contrast agent). CE-SWI images of tumour-bearing mice were directly compared to histology, confirming that CE-SWI depicts the vessels supplying and draining the tumour. We propose that CE-SWI is a very promising tool for the characterization of tumour vasculature. (orig.)

  17. Investigating flood susceptible areas in inaccessible regions using remote sensing and geographic information systems.

    Science.gov (United States)

    Lim, Joongbin; Lee, Kyoo-Seock

    2017-03-01

    Every summer, North Korea (NK) suffers from floods, resulting in decreased agricultural production and huge economic loss. Besides meteorological reasons, several factors can accelerate flood damage. Environmental studies about NK are difficult because NK is inaccessible due to the division of Korea. Remote sensing (RS) can be used to delineate flood inundated areas in inaccessible regions such as NK. The objective of this study was to investigate the spatial characteristics of flood susceptible areas (FSAs) using multi-temporal RS data and digital elevation model data. Such study will provide basic information to restore FSAs after reunification. Defining FSAs at the study site revealed that rice paddies with low elevation and low slope were the most susceptible areas to flood in NK. Numerous sediments from upper streams, especially streams through crop field areas on steeply sloped hills, might have been transported and deposited into stream channels, thus disturbing water flow. In conclusion, NK floods may have occurred not only due to meteorological factors but also due to inappropriate land use for flood management. In order to mitigate NK flood damage, reforestation is needed for terraced crop fields. In addition, drainage capacity for middle stream channel near rice paddies should be improved.

  18. Assessment of flood susceptible areas using spatially explicit, probabilistic multi-criteria decision analysis

    Science.gov (United States)

    Tang, Zhongqian; Zhang, Hua; Yi, Shanzhen; Xiao, Yangfan

    2018-03-01

    GIS-based multi-criteria decision analysis (MCDA) is increasingly used to support flood risk assessment. However, conventional GIS-MCDA methods fail to adequately represent spatial variability and are accompanied with considerable uncertainty. It is, thus, important to incorporate spatial variability and uncertainty into GIS-based decision analysis procedures. This research develops a spatially explicit, probabilistic GIS-MCDA approach for the delineation of potentially flood susceptible areas. The approach integrates the probabilistic and the local ordered weighted averaging (OWA) methods via Monte Carlo simulation, to take into account the uncertainty related to criteria weights, spatial heterogeneity of preferences and the risk attitude of the analyst. The approach is applied to a pilot study for the Gucheng County, central China, heavily affected by the hazardous 2012 flood. A GIS database of six geomorphological and hydrometeorological factors for the evaluation of susceptibility was created. Moreover, uncertainty and sensitivity analysis were performed to investigate the robustness of the model. The results indicate that the ensemble method improves the robustness of the model outcomes with respect to variation in criteria weights and identifies which criteria weights are most responsible for the variability of model outcomes. Therefore, the proposed approach is an improvement over the conventional deterministic method and can provides a more rational, objective and unbiased tool for flood susceptibility evaluation.

  19. Landslide susceptibility mapping in Mawat area, Kurdistan Region, NE Iraq: a comparison of different statistical models

    Science.gov (United States)

    Othman, A. A.; Gloaguen, R.; Andreani, L.; Rahnama, M.

    2015-03-01

    During the last decades, expansion of settlements into areas prone to landslides in Iraq has increased the importance of accurate hazard assessment. Susceptibility mapping provides information about hazardous locations and thus helps to potentially prevent infrastructure damage due to mass wasting. The aim of this study is to evaluate and compare frequency ratio (FR), weight of evidence (WOE), logistic regression (LR) and probit regression (PR) approaches in combination with new geomorphological indices to determine the landslide susceptibility index (LSI). We tested these four methods in Mawat area, Kurdistan Region, NE Iraq, where landslides occur frequently. For this purpose, we evaluated 16 geomorphological, geological and environmental predicting factors mainly derived from the advanced spaceborne thermal emission and reflection radiometer (ASTER) satellite. The available reference inventory includes 351 landslides representing a cumulative surface of 3.127 km2. This reference inventory was mapped from QuickBird data by manual delineation and partly verified by field survey. The areas under curve (AUC) of the receiver operating characteristic (ROC), and relative landslide density (R index) show that all models perform similarly and that focus should be put on the careful selection of proxies. The results indicate that the lithology and the slope aspects play major roles for landslide occurrences. Furthermore, this paper demonstrates that using hypsometric integral as a prediction factor instead of slope curvature gives better results and increases the accuracy of the LSI.

  20. Comparison of first-pass and second-bolus dynamic susceptibility perfusion MRI in brain tumors

    International Nuclear Information System (INIS)

    Spampinato, M.V.; Besenski, Nada; Rumboldt, Zoran; Wooten, Caroline; Dorlon, Margaret

    2006-01-01

    Our goal was to evaluate whether the T1 shortening effect caused by contrast leakage into brain tumors, a well-known confounding effect in the quantification of relative cerebral blood volume (rCBV) measurements, may be corrected by the administration of a predose of gadolinium-DTPA. As part of their presurgical imaging protocol, 25 patients with primary brain tumors underwent two consecutive dynamic susceptibility-weighted contrast-enhanced (DSC) perfusion MR studies. Intratumoral rCBV measurements and normalized rCBV values obtained during the first-pass and second-bolus studies were compared (Wilcoxon signed-ranks test). The frequency of relatively increased rCBV ratios on the second-bolus study was compared between enhancing and non-enhancing neoplasms (Fisher's exact test). Postprocessing perfusion studies were evaluated for image quality on a scale of 0-3 (Wilcoxon signed-ranks test). Four studies were excluded due to unacceptable image quality. Mean normalized rCBVs were 9.04 (SD 4.64) for the first-pass and 7.99 (SD 3.84) for the second-bolus study. There was no statistically significant difference between the two perfusion studies in either intratumoral rCBV (P=0.237) or rCBV ratio (P=0.181). Five enhancing and four non-enhancing tumors showed a relative increase in rCBV ratio on the second-bolus study, without a significant difference between the groups. Image quality was not significantly different between perfusion studies. Our results did not demonstrate a significant difference between first-pass and second-bolus rCBV measurements in DSC perfusion MR imaging. The administration of a predose of gadolinium-DTPA does not appear to be an efficient way of compensating for the underestimation of intratumoral rCBV values due to the T1 shortening effect. (orig.)

  1. CCDC26, CDKN2BAS, RTEL1 and TERT Polymorphisms in pediatric brain tumor susceptibility.

    Science.gov (United States)

    Adel Fahmideh, Maral; Lavebratt, Catharina; Schüz, Joachim; Röösli, Martin; Tynes, Tore; Grotzer, Michael A; Johansen, Christoffer; Kuehni, Claudia E; Lannering, Birgitta; Prochazka, Michaela; Schmidt, Lisbeth S; Feychting, Maria

    2015-08-01

    The role of genetic polymorphisms in pediatric brain tumor (PBT) etiology is poorly understood. We hypothesized that single nucleotide polymorphisms (SNPs) identified in genome-wide association studies (GWAS) on adult glioma would also be associated with PBT risk. The study is based on the Cefalo study, a population-based multicenter case-control study. Saliva DNA from 245 cases and 489 controls, aged 7-19 years at diagnosis/reference date, was extracted and genotyped for 29 SNPs reported by GWAS to be significantly associated with risk of adult glioma. Data were analyzed using unconditional logistic regression. Stratified analyses were performed for two histological subtypes: astrocytoma alone and the other tumor types combined. The results indicated that four SNPs, CDKN2BAS rs4977756 (p = 0.036), rs1412829 (p = 0.037), rs2157719 (p = 0.018) and rs1063192 (p = 0.021), were associated with an increased susceptibility to PBTs, whereas the TERT rs2736100 was associated with a decreased risk (p = 0.018). Moreover, the stratified analyses showed a decreased risk of astrocytoma associated with RTEL1 rs6089953, rs6010620 and rs2297440 (p trend = 0.022, p trend = 0.042, p trend = 0.029, respectively) as well as an increased risk of this subtype associated with RTEL1 rs4809324 (p trend = 0.033). In addition, SNPs rs10464870 and rs891835 in CCDC26 were associated with an increased risk of non-astrocytoma tumor subtypes (p trend = 0.009, p trend = 0.007, respectively). Our findings indicate that SNPs in CDKN2BAS, TERT, RTEL1 and CCDC26 may be associated with the risk of PBTs. Therefore, we suggest that pediatric and adult brain tumors might share common genetic risk factors and similar etiological pathways. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Mice lacking glutamate carboxypeptidase II develop normally, but are less susceptible to traumatic brain injury.

    Science.gov (United States)

    Gao, Yang; Xu, Siyi; Cui, Zhenwen; Zhang, Mingkun; Lin, Yingying; Cai, Lei; Wang, Zhugang; Luo, Xingguang; Zheng, Yan; Wang, Yong; Luo, Qizhong; Jiang, Jiyao; Neale, Joseph H; Zhong, Chunlong

    2015-07-01

    Glutamate carboxypeptidase II (GCPII) is a transmembrane zinc metallopeptidase found mainly in the nervous system, prostate and small intestine. In the nervous system, glia-bound GCPII mediates the hydrolysis of the neurotransmitter N-acetylaspartylglutamate (NAAG) into glutamate and N-acetylaspartate. Inhibition of GCPII has been shown to attenuate excitotoxicity associated with enhanced glutamate transmission under pathological conditions. However, different strains of mice lacking the GCPII gene are reported to exhibit striking phenotypic differences. In this study, a GCPII gene knockout (KO) strategy involved removing exons 3-5 of GCPII. This generated a new GCPII KO mice line with no overt differences in standard neurological behavior compared to their wild-type (WT) littermates. However, GCPII KO mice were significantly less susceptible to moderate traumatic brain injury (TBI). GCPII gene KO significantly lessened neuronal degeneration and astrocyte damage in the CA2 and CA3 regions of the hippocampus 24 h after moderate TBI. In addition, GCPII gene KO reduced TBI-induced deficits in long-term spatial learning/memory tested in the Morris water maze and motor balance tested via beam walking. Knockout of the GCPII gene is not embryonic lethal and affords histopathological protection with improved long-term behavioral outcomes after TBI, a result that further validates GCPII as a target for drug development consistent with results from studies using GCPII peptidase inhibitors. © 2015 International Society for Neurochemistry.

  3. Changes of deep gray matter magnetic susceptibility over 2years in multiple sclerosis and healthy control brain

    Directory of Open Access Journals (Sweden)

    Jesper Hagemeier

    Full Text Available In multiple sclerosis, pathological changes of both tissue iron and myelin occur, yet these factors have not been characterized in a longitudinal fashion using the novel iron- and myelin-sensitive quantitative susceptibility mapping (QSM MRI technique. We investigated disease-relevant tissue changes associated with myelin loss and iron accumulation in multiple sclerosis deep gray matter (DGM over two years. One-hundred twenty (120 multiple sclerosis patients and 40 age- and sex-matched healthy controls were included in this prospective study. Written informed consent and local IRB approval were obtained from all participants. Clinical testing and QSM were performed both at baseline and at follow-up. Brain magnetic susceptibility was measured in major DGM structures. Temporal (baseline vs. follow-up and cross-sectional (multiple sclerosis vs. controls differences were studied using mixed factorial ANOVA analysis and appropriate t-tests. At either time-point, multiple sclerosis patients had significantly higher susceptibility in the caudate and globus pallidus and lower susceptibility in the thalamus. Over two years, susceptibility increased significantly in the caudate of both controls and multiple sclerosis patients. Inverse thalamic findings among MS patients suggest a multi-phase pathology explained by simultaneous myelin loss and/or iron accumulation followed by iron depletion and/or calcium deposition at later stages. Keywords: Quantitative susceptibility mapping, QSM, Iron, Multiple sclerosis, Longitudinal study

  4. Food-Related Odors Activate Dopaminergic Brain Areas

    Directory of Open Access Journals (Sweden)

    Agnieszka Sorokowska

    2017-12-01

    Full Text Available Food-associated cues of different sensory categories have often been shown to be a potent elicitor of cerebral activity in brain reward circuits. Smells influence and modify the hedonic qualities of eating experience, and in contrast to smells not associated with food, perception of food-associated odors may activate dopaminergic brain areas. In this study, we aimed to verify previous findings related to the rewarding value of food-associated odors by means of an fMRI design involving carefully preselected odors of edible and non-edible substances. We compared activations generated by three food and three non-food odorants matching in terms of intensity, pleasantness and trigeminal qualities. We observed that for our mixed sample of 30 hungry and satiated participants, food odors generated significantly higher activation in the anterior cingulate cortex (right and left, insula (right, and putamen (right than non-food odors. Among hungry subjects, regardless of the odor type, we found significant activation in the ventral tegmental area in response to olfactory stimulation. As our stimuli were matched in terms of various perceptual qualities, this result suggests that edibility of an odor source indeed generates specific activation in dopaminergic brain areas.

  5. In vitro antimalarial drug susceptibility in Thai border areas from 1998–2003

    Directory of Open Access Journals (Sweden)

    Mungthin Mathirut

    2005-08-01

    Full Text Available Abstract Background The Thai-Myanmar and Thai-Cambodia borders have been historically linked with the emergence and spread of Plasmodium falciparum parasites resistant to antimalarial drugs. Indeed, the areas are often described as harbouring multi-drug resistant parasites. These areas of Thailand have experienced significant changes in antimalarial drug exposure patterns over the past decade. This study describes the in vitro antimalarial susceptibility patterns of 95 laboratory-adapted P. falciparum isolates, collected between 1998 and 2003,. Methods Ninety five P. falciparum isolates were collected from five sites in Thailand between 1998 and 2003. After laboratory adaptation to in vitro culture, the susceptibility of these parasites to a range of established antimalarial drugs (chloroquine [CQ], mefloquine [MQ], quinine [QN] and dihydroartemisinin [DHA] was determined by the isotopic microtest. Results Mefloquine (MQ sensitivity remained poorest in areas previously described as MQ-resistant areas. Sensitivity to MQ of parasites from this area was significantly lower than those from areas reported to harbour moderate (p = 0.002 of low level MQ resistance (p = 000001. Importantly for all drugs tested, there was a considerable range in absolute parasite sensitivities. There was a weak, but statistically positive correlation between parasite sensitivity to CQ and sensitivity to both QN and MQ and a positive correlation between MQ and QN. In terms of geographical distribution, parasites from the Thai-Cambodia were tended to be less sensitive to all drugs tested compared to the Thai-Myanmar border. Parasite sensitivity to all drugs was stable over the 6-year collection period with the exception of QN. Conclusion This study highlights the high degree of variability in parasite drug sensitivity in Thailand. There were geographical differences in the pattern of resistance which might reflect differences in drug usage in each area. In contrast to many

  6. Intrinsic functional brain mapping in reconstructed 4D magnetic susceptibility (χ) data space.

    Science.gov (United States)

    Chen, Zikuan; Calhoun, Vince

    2015-02-15

    By solving an inverse problem of T2*-weighted magnetic resonance imaging for a dynamic fMRI study, we reconstruct a 4D magnetic susceptibility source (χ) data space for intrinsic functional mapping. A 4D phase dataset is calculated from a 4D complex fMRI dataset. The background field and phase wrapping effect are removed by a Laplacian technique. A 3D χ source map is reconstructed from a 3D phase image by a computed inverse MRI (CIMRI) scheme. A 4D χ data space is reconstructed by repeating the 3D χ source reconstruction for each time point. A functional map is calculated by a temporal correlation between voxel signals in the 4D χ space and the timecourse of the task paradigm. With a finger-tapping experiment, we obtain two 3D functional mappings in the 4D magnitude data space and in the reconstructed 4D χ data space. We find that the χ-based functional mapping reveals co-occurrence of bidirectional responses in a 3D activation map that is different from the conventional magnitude-based mapping. The χ-based functional mapping can also be achieved by a 3D deconvolution of a phase activation map. Based on a subject experimental comparison, we show that the 4D χ tomography method could produce a similar χ activation map as obtained by the 3D deconvolution method. By removing the dipole effect and other fMRI technological contaminations, 4D χ tomography provides a 4D χ data space that allows a more direct and truthful functional mapping of a brain activity. Published by Elsevier B.V.

  7. A Novel Human Body Area Network for Brain Diseases Analysis.

    Science.gov (United States)

    Lin, Kai; Xu, Tianlang

    2016-10-01

    Development of wireless sensor and mobile communication technology provide an unprecedented opportunity for realizing smart and interactive healthcare systems. Designing such systems aims to remotely monitor the health and diagnose the diseases for users. In this paper, we design a novel human body area network for brain diseases analysis, which is named BABDA. Considering the brain is one of the most complex organs in the human body, the BABDA system provides four function modules to ensure the high quality of the analysis result, which includes initial data collection, data correction, data transmission and comprehensive data analysis. The performance evaluation conducted in a realistic environment with several criteria shows the availability and practicability of the BABDA system.

  8. USING GIS TO IDENTIFY POTENTIAL AREAS SUSCEPTIBLE TO FLOOD. CASE STUDY: SOLONEŢ RIVER

    Directory of Open Access Journals (Sweden)

    V. TIPLEA

    2011-03-01

    Full Text Available Using GIS to Identify Potential Areas Susceptible to Flood. Case Study: Soloneţ River. In this study, we aim to analyze the impact of different peak flows in territory and also a better understanding of the dynamic of a river flow. The methodology used for flood zone delimitation is based on a quantitative analysis model which requires the use of mathematical, physical and statistical operations in order to emphasize the relations between the different variables that were implied (discharges, grain size, terrain morphology, soil saturation, vegetation etc.. The results cannot be expected to be completely accurate but can provide a good representation of the process. Validation of results will inevitably be difficult and should be measured in the field. The information resulting from this study could be useful for raising awareness about both hazards and possible mitigation measure, a key component of disaster risk reduction planning.

  9. Activated and deactivated functional brain areas in the Deqi state

    OpenAIRE

    Huang, Yong; Zeng, Tongjun; Zhang, Guifeng; Li, Ganlong; Lu, Na; Lai, Xinsheng; Lu, Yangjia; Chen, Jiarong

    2012-01-01

    We compared the activities of functional regions of the brain in the Deqi versus non-Deqi state, as reported by physicians and subjects during acupuncture. Twelve healthy volunteers received sham and true needling at the Waiguan (TE5) acupoint. Real-time cerebral functional MRI showed that compared with non-sensation after sham needling, true needling activated Brodmann areas 3, 6, 8, 9, 10, 11, 13, 20, 21, 37, 39, 40, 43, and 47, the head of the caudate nucleus, the parahippocampal gyrus, th...

  10. How Localized are Language Brain Areas? A Review of Brodmann Areas Involvement in Oral Language.

    Science.gov (United States)

    Ardila, Alfredo; Bernal, Byron; Rosselli, Monica

    2016-02-01

    The interest in understanding how language is "localized" in the brain has existed for centuries. Departing from seven meta-analytic studies of functional magnetic resonance imaging activity during the performance of different language activities, it is proposed here that there are two different language networks in the brain: first, a language reception/understanding system, including a "core Wernicke's area" involved in word recognition (BA21, BA22, BA41, and BA42), and a fringe or peripheral area ("extended Wernicke's area:" BA20, BA37, BA38, BA39, and BA40) involved in language associations (associating words with other information); second, a language production system ("Broca's complex:" BA44, BA45, and also BA46, BA47, partially BA6-mainly its mesial supplementary motor area-and extending toward the basal ganglia and the thalamus). This paper additionally proposes that the insula (BA13) plays a certain coordinating role in interconnecting these two brain language systems. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Flash Flood Hazard Susceptibility Mapping Using Frequency Ratio and Statistical Index Methods in Coalmine Subsidence Areas

    Directory of Open Access Journals (Sweden)

    Chen Cao

    2016-09-01

    Full Text Available This study focused on producing flash flood hazard susceptibility maps (FFHSM using frequency ratio (FR and statistical index (SI models in the Xiqu Gully (XQG of Beijing, China. First, a total of 85 flash flood hazard locations (n = 85 were surveyed in the field and plotted using geographic information system (GIS software. Based on the flash flood hazard locations, a flood hazard inventory map was built. Seventy percent (n = 60 of the flooding hazard locations were randomly selected for building the models. The remaining 30% (n = 25 of the flooded hazard locations were used for validation. Considering that the XQG used to be a coal mining area, coalmine caves and subsidence caused by coal mining exist in this catchment, as well as many ground fissures. Thus, this study took the subsidence risk level into consideration for FFHSM. The ten conditioning parameters were elevation, slope, curvature, land use, geology, soil texture, subsidence risk area, stream power index (SPI, topographic wetness index (TWI, and short-term heavy rain. This study also tested different classification schemes for the values for each conditional parameter and checked their impacts on the results. The accuracy of the FFHSM was validated using area under the curve (AUC analysis. Classification accuracies were 86.61%, 83.35%, and 78.52% using frequency ratio (FR-natural breaks, statistical index (SI-natural breaks and FR-manual classification schemes, respectively. Associated prediction accuracies were 83.69%, 81.22%, and 74.23%, respectively. It was found that FR modeling using a natural breaks classification method was more appropriate for generating FFHSM for the Xiqu Gully.

  12. [Quantitative magnetic resonance imaging of brain iron deposition: comparison between quantitative susceptibility mapping and transverse relaxation rate (R2*) mapping].

    Science.gov (United States)

    Guan, Ji-Jing; Feng, Yan-Qiu

    2018-03-20

    To evaluate the accuracy and sensitivity of quantitative susceptibility mapping (QSM) and transverse relaxation rate (R2*) mapping in the measurement of brain iron deposition. Super paramagnetic iron oxide (SPIO) phantoms and mouse models of Parkinson's disease (PD) related to iron deposition in the substantia nigra (SN) underwent 7.0 T magnetic resonance (MR) scans (Bruker, 70/16) with a multi-echo 3D gradient echo sequence, and the acquired data were processed to obtain QSM and R2*. Linear regression analysis was performed for susceptibility and R2* in the SPIO phantoms containing 5 SPIO concentrations (30, 15, 7.5, 3.75 and 1.875 µg/mL) to evaluate the accuracy of QSM and R2* in quantitative iron analysis. The sensitivities of QSM and R2* mapping in quantitative detection of brain iron deposition were assessed using mouse models of PD induced by 1-methyl-4-phenyl-1,2,3,6-tetrahy-dropyridine (MPTP) in comparison with the control mice. In SPIO phantoms, QSM provided a higher accuracy than R2* mapping and their goodness-of-fit coefficients (R 2 ) were 0.98 and 0.89, respectively. In the mouse models of PD and control mice, the susceptibility of the SN was significantly higher in the PD models (5.19∓1.58 vs 2.98∓0.88, n=5; Pbrain iron deposition than R2*, and the susceptibility derived by QSM can be a potentially useful biomarker for studying PD.

  13. Application of a neuro-fuzzy model to landslide-susceptibility mapping for shallow landslides in a tropical hilly area

    Science.gov (United States)

    Oh, Hyun-Joo; Pradhan, Biswajeet

    2011-09-01

    This paper presents landslide-susceptibility mapping using an adaptive neuro-fuzzy inference system (ANFIS) using a geographic information system (GIS) environment. In the first stage, landslide locations from the study area were identified by interpreting aerial photographs and supported by an extensive field survey. In the second stage, landslide-related conditioning factors such as altitude, slope angle, plan curvature, distance to drainage, distance to road, soil texture and stream power index (SPI) were extracted from the topographic and soil maps. Then, landslide-susceptible areas were analyzed by the ANFIS approach and mapped using landslide-conditioning factors. In particular, various membership functions (MFs) were applied for the landslide-susceptibility mapping and their results were compared with the field-verified landslide locations. Additionally, the receiver operating characteristics (ROC) curve for all landslide susceptibility maps were drawn and the areas under curve values were calculated. The ROC curve technique is based on the plotting of model sensitivity — true positive fraction values calculated for different threshold values, versus model specificity — true negative fraction values, on a graph. Landslide test locations that were not used during the ANFIS modeling purpose were used to validate the landslide susceptibility maps. The validation results revealed that the susceptibility maps constructed by the ANFIS predictive models using triangular, trapezoidal, generalized bell and polynomial MFs produced reasonable results (84.39%), which can be used for preliminary land-use planning. Finally, the authors concluded that ANFIS is a very useful and an effective tool in regional landslide susceptibility assessment.

  14. Disrupted modular organization of primary sensory brain areas in schizophrenia

    Directory of Open Access Journals (Sweden)

    Cécile Bordier

    Full Text Available Abnormal brain resting-state functional connectivity has been consistently observed in patients affected by schizophrenia (SCZ using functional MRI and other neuroimaging techniques. Graph theoretical methods provide a framework to investigate these defective functional interactions and their effects on the organization of brain connectivity networks. A few studies have shown altered distribution of connectivity within and between functional modules in SCZ patients, an indication of imbalanced functional segregation ad integration. However, no major alterations of modular organization have been reported in patients, and unambiguous identification of the neural substrates affected remains elusive. Recently, it has been demonstrated that current modularity analysis methods suffer from a fundamental and severe resolution limit, as they fail to detect features that are smaller than a scale determined by the size of the entire connectivity network. This resolution limit is likely to have hampered the ability to resolve differences between patients and controls in previous studies. Here, we apply Surprise, a novel resolution limit-free approach, to study the modular organization of resting state functional connectivity networks in a large cohort of SCZ patients and in matched healthy controls. Leveraging these important methodological advances we find new evidence of substantial fragmentation and reorganization involving primary sensory, auditory and visual areas in SCZ patients. Conversely, frontal and prefrontal areas, typically associated with higher cognitive functions, appear to be largely unaffected, with changes selectively involving language and speech processing areas. Our findings support the hypothesis that cognitive dysfunction in SCZ may involve deficits occurring already at early stages of sensory processing. Keywords: Schizophrenia, Surprise, Asymptotical surprise, Functional connectivity, Community detection, Modularity, Graph theory

  15. From rainfall to slope instability: an automatic GIS procedure for susceptibility analyses over wide areas

    Directory of Open Access Journals (Sweden)

    Bianca Federici

    2015-07-01

    Full Text Available The paper proposes an automatic procedure in geographic information system (GIS for the analysis and prediction of landslides due to rainfall events over wide areas. It runs, for each unit cell, a hydrological balance based on the Curve Number method (USDA-SCS 1985–1986, computing the evolution of groundwater as a result of precipitation and then checks the overcoming, or not, of limit equilibrium conditions of the land in the domain of interest. The mathematical model was implemented in the free and open source GIS GRASS. For any sequence of consecutive days of rain, according to the conditions of soil moisture prior to the time history under study, the hydro-geotechnical model allows (1 the determination of the oscillations of the phreatic table, (2 the part of saturated soil and (3 the slope stability analysis, by taking into proper account the pore pressures buildup. The results of this procedure are returned in raster format, allowing an easy and intuitive interpretation of the land mass sensitivity to meteoric actions. The suggested procedure was applied on an extensive kinematic phenomenon surrounding the city of Santo Stefano d’Aveto (Liguria, Italy. The realized maps of landslide susceptibility are in excellent agreement with what is evident on site.

  16. Georeferenced measurement of soil EC as a tool to detect susceptible areas to water erosion.

    Science.gov (United States)

    Fabian Sallesses, Leonardo; Aparicio, Virginia Carolina; Costa, Jose Luis

    2017-04-01

    areas presented the highest occurrence of clay dispersion and rill erosion. This would indicate that with one campaign of cultivation of potato under supplementary irrigation are given the conditions that facilitate erosive events. The georeferenced measurement of EC by contact ground sensors and their visualization through digital cartography could be an interesting tool to detect areas susceptible to erosive events. This information would help in decision making for a soil management that tends to avoid or reduce soil losses due to deterioration of physical and chemical properties by the incorporation of sodium by irrigation. Key words: Irrigation, soil sodium, erosion.

  17. Susceptibility contrast imaging of CO2-induced changes in the blood volume of the human brain

    DEFF Research Database (Denmark)

    Rostrup, Egill; Larsson, H B; Toft, P B

    1996-01-01

    PURPOSE: To investigate changes in the regional cerebral blood volume (rCBV) in human subjects during rest and hypercapnia by MR imaging, and to compare the results from contrast-enhanced and noncontrast-enhanced susceptibility-weighted imaging. MATERIAL AND METHODS: Five healthy volunteers (aged...

  18. Seroprevalence and susceptibility to hepatitis A in the European Union and European Economic Area: a systematic review.

    Science.gov (United States)

    Carrillo-Santisteve, Paloma; Tavoschi, Lara; Severi, Ettore; Bonfigli, Sandro; Edelstein, Michael; Byström, Emma; Lopalco, Pierluigi

    2017-10-01

    Most of the European Union (EU) and European Economic Area (EEA) is considered a region of very low hepatitis A virus (HAV) endemicity; however, geographical differences exist. We did a systematic review with the aim of describing seroprevalence and susceptibility in the general population or special groups in the EU and EEA. We searched databases and public health national institutes websites for HAV seroprevalence records published between Jan 1, 1975, and June 30, 2014, with no language restrictions. An updated search was done on Aug 10, 2016. We defined seroprevalence profiles (very low, low, and intermediate) as the proportion of the population with age-specific anti-HAV antibodies at age 15 and 30 years, and susceptibility profiles (low, moderate, high, and very high) as the proportion of susceptible individuals at age 30 and 50 years. We included 228 studies from 28 of 31 EU and EEA countries. For the period 2000-14, 24 countries had a very low seroprevalence profile, compared with five in 1975-89. The susceptibility among adults ranged between low and very high and had a geographical gradient, with three countries in the low susceptibility category. Since 1975, EU and EEA countries have shown decreasing seropositivity; however, considerable regional variability exists. The main limitations of this study are that the studies retrieved for analysis might not be representative of all EU and EEA publications about HAV and might have poor national representativeness. A large proportion of EU and EEA residents are now susceptible to HAV infection. Our Review supports the need to reconsider specific prevention and control measures, to further decrease HAV circulation while providing protection against the infection in the EU and EEA, and could be used to inform susceptible travellers visiting EU and EEA countries with different HAV endemicity levels. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. The brain-specific factor FEZ1 is a determinant of neuronal susceptibility to HIV-1 infection.

    LENUS (Irish Health Repository)

    Haedicke, Juliane

    2009-08-18

    Neurons are one of the few cell types in the human body that do not support HIV type-1 (HIV-1) replication. Although the lack of key receptors is a major obstacle to infection, studies suggest that additional functions inhibit virus replication to explain the exquisite resistance of neurons to HIV-1. However, specific neuronal factors that may explain this resistance remain to be discovered. In a screen for antiviral factors using a fibroblast line chemically mutagenized and selected for resistance to retroviral infection, we recently identified induction of rat FEZ1 (fasciculation and elongation protein zeta-1), a brain-specific protein, as the cause of this resistance. When exogenously expressed in nonneuronal cell lines rat FEZ1 blocked nuclear entry of retroviral DNA. Here, we demonstrate that among human brain cells, neurons naturally express high levels of FEZ1 compared to astrocytes or microglia cells and are correspondingly less susceptible to infection with pseudotyped HIV-1 that bypasses receptor-mediated viral entry. Demonstrating that endogenous FEZ1 was functionally important in the resistance of neurons to HIV-1 infection, siRNA-mediated knockdown of endogenous FEZ1 increased the infectivity of neurons while sensitive brain cell types like microglia became more resistant upon FEZ1 overexpression. In addition, FEZ1 expression was not induced in response to IFN treatment. As such, in contrast to other widely expressed, IFN-inducible antiviral factors, FEZ1 appears to represent a unique neuron-specific determinant of cellular susceptibility to infection in a cell type that is naturally resistant to HIV-1.

  20. Susceptibility contrast imaging of CO2-induced changes in the blood volume of the human brain

    DEFF Research Database (Denmark)

    Rostrup, Egill; Larsson, H B; Toft, P B

    1996-01-01

    PURPOSE: To investigate changes in the regional cerebral blood volume (rCBV) in human subjects during rest and hypercapnia by MR imaging, and to compare the results from contrast-enhanced and noncontrast-enhanced susceptibility-weighted imaging. MATERIAL AND METHODS: Five healthy volunteers (aged...... in cerebral hemodynamics than noncontrast-enhanced imaging. The results of the deconvolution analysis suggested that perfusion calculation by conventional tracer kinetic methods may be impracticable because of nonlinear effects in contrast-enhanced MR imaging....

  1. Combined value of susceptibility weighted imaging and dynamic susceptibility-weighted contrast-enhanced MR perfusion-weighted imaging in brain astrocytoma grading

    International Nuclear Information System (INIS)

    Wang Xiaochun; Zhang Hui; Qin Jiangbo; Wang Le; Wu Xiaofeng

    2012-01-01

    Objective: To assess the value of combination of susceptibility weighted imaging (SWI) and dynamic susceptibility-weighted contrast-enhanced (DSC) perfusion-weighted magnetic resonance imaging in astrocytoma grading. Methods: SWI and DSC scans were performed in 82 patients with pathologically confirmed astrocytoma. The patient group consisted of grade Ⅱ (15), grade Ⅲ (10), and grade Ⅳ (57). The intratumoral susceptibility signal intensity (ITSS) and relative cerebral blood volume (rCBV) max were used to determine the grade of astrocytomas by Kruskal Wallis test, Welch test, Spearman correlation coefficients, Pearson correlation coefficients, and receiver operating characteristic curve (ROC)statistic methods. Results: There were no ITSS in 14 cases of low-grade astrocytomas, the degree of ITSS were grade 1 to 3 in anaplastic astrocytomas, the degree of ITSS were grade 3 in all of the glioblastomas, the degree of ITSS were significant difference in all grades (H=71.96, P<0.01). rCBV max in grade Ⅱ, grade Ⅲ and grade Ⅳ astrocytomas were 1.26 ± 0.42, 3.59 ± 2.09 and 8.34 ± 1.16 respectively, rCBV max were significant difference in all grades (F'=681.72, P<0.01). ITSS showed significant correlation with rCBV max (r=0.72, P<0.01) and tumor grades (r=0.89, P<0.01), and rCBV and tumor grades showed significant correlation (r=0.78, P<0.01). Area under the ROC curve application SWI, DSC, SWI and DSC in differentiation of the grade Ⅱ and grade Ⅲ astrocytomas were 0.99, 0.93, 1.00, differentiate grade Ⅲ from grade Ⅳ were 0.70, 0.94, 0.94, and differentiate high-grade from low-grade astrocytomas were 1.00, 0.99, 1.00. Conclusions: ITSS is helpful to determine the grade of astrocytomas. The use of SWI in combination with DSC may improve the diagnostic accuracy of astrocytoma grading. (authors)

  2. Age-related deposition of brain iron in normal adults: an in vivo susceptibility weighted imaging study

    International Nuclear Information System (INIS)

    Wang Qidong; Xu Xiaojun; Zhang Minming

    2008-01-01

    Objective: The purpose of this study was to investigate the effect of age on the iron concentration of the human brain. Methods: The brain iron level was evaluated in vivo in 78 healthy adult volunteers using a noninvasive magnetic resonance method termed susceptibility weighted imaging. The subjects were divided intothree groups due to different ages: young (22-35 years old, n=27), middle- aged (36-55 years old, n=35), and aged (56-78 years old, n=16). The phase values were measured on the corrected phase images in the globus pallidus, putamen, caudate, substantia nigra, red nucleus, thalamus and frontal white matter. The phase values of those regions measured from the subjects over than 30 years old were correlated with published values of brain iron concentration in normal adults to check the validity of the data. Then, the phase values of the three groups were tested for significant age-related differences using one-way ANOVA, followed by post hoc testing using least significant difference (LSD) procedure. Regression analysis was used to further examine age-related effects revealed by group comparisons, and to estimate the rates of age-related changes. Results: A strong negative correlation was found between the phase values and the published values of the brain iron concentration (r=-0.796, P= 0.032), which indicated that the higher the iron deposition level, the greater the negative phase values. In the putamen (F=20.115, P<0.01) and frontal white matter (F=3.536, P=0.034), significant differences were detected in the phase values of the three age groups. Linear regression analysis showed that phase values of the putamen, frontal white matter, and red nucleus decreased with age (The regression coefficients were -0.001, -0.001, and < -0.001 respectively, and the P value were all < 0.05), which indicated that the iron concentration of those brain structures increased with age. No significant age- related changes of the iron concentration were found in the

  3. Susceptibility loci for sporadic brain arteriovenous malformation; a replication study and meta-analysis

    NARCIS (Netherlands)

    Kremer, P.H.; Koeleman, B.P.C.; Rinkel, G.J.; Diekstra, F.P.; Berg, L.H. van den; Veldink, J.H.; Klijn, C.J.M.

    2016-01-01

    BACKGROUND: Case-control studies have reported multiple genetic loci to be associated with sporadic brain arteriovenous malformations (AVMs) but most of these have not been replicated in independent populations. The aim of this study was to find additional evidence for these reported associations

  4. Evidence implicating BRD1 with brain development and susceptibility to both schizophrenia and bipolar affective disorder

    DEFF Research Database (Denmark)

    Severinsen, Jacob; Bjarkam, Carsten; Kiær-Larsen, Stine

    . Quantitative mRNA analysis in developing fetal pig brain revealed spatiotemporal differences with high expression at early embryonic stages, with intense nuclear and cytosolar immunohistochemical staining of the neuroepithelial layer and early neuroblasts, whilst more mature neurons at later embryonic stages...

  5. Susceptibility contrast imaging of CO2-induced changes in the blood volume of the human brain

    DEFF Research Database (Denmark)

    Rostrup, Egill; Larsson, H B; Toft, P B

    1996-01-01

    PURPOSE: To investigate changes in the regional cerebral blood volume (rCBV) in human subjects during rest and hypercapnia by MR imaging, and to compare the results from contrast-enhanced and noncontrast-enhanced susceptibility-weighted imaging. MATERIAL AND METHODS: Five healthy volunteers (aged...... to be in accordance with results obtained by other methods. Noncontrast functional MR (fMR) imaging showed signal increases in gray matter, but also inconsistent changes in some white matter regions. CONCLUSION: In this experiment, contrast-enhanced imaging seemed to show a somewhat higher sensitivity towards changes...

  6. Pathological Area Detection in MR Images of Brain

    Czech Academy of Sciences Publication Activity Database

    Dvořák, P.; Kropatsch, W.G.; Bartušek, Karel

    2013-01-01

    Roč. 4, č. 1 (2013), s. 17-21 ISSN 1213-1539 R&D Projects: GA ČR GAP102/12/1104; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : Brain * Brain tumor detection * MR * Symmetry analysis Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  7. Neural - levelset shape detection segmentation of brain tumors in dynamic susceptibility contrast enhanced and diffusion weighted magnetic resonance images

    International Nuclear Information System (INIS)

    Vijayakumar, C.; Bhargava, Sunil; Gharpure, Damayanti Chandrashekhar

    2008-01-01

    A novel Neuro - level set shape detection algorithm is proposed and evaluated for segmentation and grading of brain tumours. The algorithm evaluates vascular and cellular information provided by dynamic contrast susceptibility magnetic resonance images and apparent diffusion coefficient maps. The proposed neural shape detection algorithm is based on the levels at algorithm (shape detection algorithm) and utilizes a neural block to provide the speed image for the level set methods. In this study, two different architectures of level set method have been implemented and their results are compared. The results show that the proposed Neuro-shape detection performs better in differentiating the tumor, edema, necrosis in reconstructed images of perfusion and diffusion weighted magnetic resonance images. (author)

  8. The role of dynamic susceptibility contrast-enhanced perfusion MR imaging in differentiating between infectious and neoplastic focal brain lesions: results from a cohort of 100 consecutive patients.

    Directory of Open Access Journals (Sweden)

    Valdeci Hélio Floriano

    Full Text Available BACKGROUND AND PURPOSE: Differentiating between infectious and neoplastic focal brain lesions that are detected by conventional structural magnetic resonance imaging (MRI may be a challenge in routine practice. Brain perfusion-weighted MRI (PWI may be employed as a complementary non-invasive tool, providing relevant data on hemodynamic parameters, such as the degree of angiogenesis of lesions. We aimed to employ dynamic susceptibility contrast-enhanced perfusion MR imaging (DSC-MRI to differentiate between infectious and neoplastic brain lesions by investigating brain microcirculation changes. MATERIALS AND METHODS: DSC-MRI perfusion studies of one hundred consecutive patients with non-cortical neoplastic (n = 54 and infectious (n = 46 lesions were retrospectively assessed. MRI examinations were performed using a 1.5-T scanner. A preload of paramagnetic contrast agent (gadolinium was administered 30 seconds before acquisition of dynamic images, followed by a standard dose 10 seconds after starting imaging acquisitions. The relative cerebral blood volume (rCBV values were determined by calculating the regional cerebral blood volume in the solid areas of lesions, normalized to that of the contralateral normal-appearing white matter. Discriminant analyses were performed to determine the cutoff point of rCBV values that would allow the differentiation of neoplastic from infectious lesions and to assess the corresponding diagnostic performance of rCBV when using this cutoff value. RESULTS: Neoplastic lesions had higher rCBV values (4.28±2.11 than infectious lesions (0.63±0.49 (p<0.001. When using an rCBV value <1.3 as the parameter to define infectious lesions, the sensitivity of the method was 97.8% and the specificity was 92.6%, with a positive predictive value of 91.8%, a negative predictive value of 98.0%, and an accuracy of 95.0%. CONCLUSION: PWI is a useful complementary tool in distinguishing between infectious and neoplastic brain

  9. Prioritising watersheds on the basis of regional flood susceptibility and vulnerability in mountainous areas through the use of indicators

    Science.gov (United States)

    Rogelis, Carolina; Werner, Micha

    2013-04-01

    Settlements in peri-urban areas of many cities in mountainous areas such as in the Andes are susceptible to hazards such as flash floods and debris flows. Additionally these settlements are in many cases informal and thus vulnerable to such hazards, resulting in significant risk. Such watersheds are often quiet small, and generally there is little or no information from gauges to help characterise risk. To help identify watersheds in which flood management measures are to be targeted, a rapid assessment of risk is required. In this paper a novel approach is presented where indicators of susceptibility and vulnerability to flash floods were used to prioritize 106 mountain watersheds in Bogotá (Colombia). Variables recognized in literature to determine the dominant processes both in susceptibility and vulnerability to flash floods were used to construct the indicators. Susceptibility was considered to increase with flashiness and the possibility of debris flow events occurring. This was assessed through the use of an indicator composed of a morphometric indicator and a land use indicator. The former was constructed using morphological variables recognized in literature to significantly influence flashiness and occurrence of debris flows; the latter was constructed in terms of percentage of vegetation cover, urban area and bare soil. The morphometric indicator was compared with the results of a debris flow propagation algorithm to assess its capacity in indentifying the morphological conditions of a watershed that make it able to transport debris flows. Propagation was carried out through the use of the Modified Single Flow Direction algorithm, following previous identification of source areas by applying thresholds identified in the area-slope curve of the watersheds and empirical thresholds. Results show that the morphometric variables can be grouped in four categories: size, shape, hypsometry and energy, with the energy the component found to best explain the

  10. Arterial stiffness, pressure and flow pulsatility and brain structure and function: the Age, Gene/Environment Susceptibility--Reykjavik study.

    Science.gov (United States)

    Mitchell, Gary F; van Buchem, Mark A; Sigurdsson, Sigurdur; Gotal, John D; Jonsdottir, Maria K; Kjartansson, Ólafur; Garcia, Melissa; Aspelund, Thor; Harris, Tamara B; Gudnason, Vilmundur; Launer, Lenore J

    2011-11-01

    Aortic stiffness increases with age and vascular risk factor exposure and is associated with increased risk for structural and functional abnormalities in the brain. High ambient flow and low impedance are thought to sensitize the cerebral microcirculation to harmful effects of excessive pressure and flow pulsatility. However, haemodynamic mechanisms contributing to structural brain lesions and cognitive impairment in the presence of high aortic stiffness remain unclear. We hypothesized that disproportionate stiffening of the proximal aorta as compared with the carotid arteries reduces wave reflection at this important interface and thereby facilitates transmission of excessive pulsatile energy into the cerebral microcirculation, leading to microvascular damage and impaired function. To assess this hypothesis, we evaluated carotid pressure and flow, carotid-femoral pulse wave velocity, brain magnetic resonance images and cognitive scores in participants in the community-based Age, Gene/Environment Susceptibility--Reykjavik study who had no history of stroke, transient ischaemic attack or dementia (n = 668, 378 females, 69-93 years of age). Aortic characteristic impedance was assessed in a random subset (n = 422) and the reflection coefficient at the aorta-carotid interface was computed. Carotid flow pulsatility index was negatively related to the aorta-carotid reflection coefficient (R = -0.66, Pwave velocity were each associated with increased risk for silent subcortical infarcts (hazard ratios of 1.62-1.71 per standard deviation, Pwave velocity was associated with higher white matter hyperintensity volume (0.108 ± 0.045 SD/SD, P = 0.018). Pulsatility index was associated with lower whole brain (-0.127 ± 0.037 SD/SD, Pwave velocity (-0.095 ± 0.043 SD/SD, P = 0.028) and carotid pulse pressure (-0.114 ± 0.045 SD/SD, P = 0.013) were associated with lower memory scores. Pulsatility index was associated with lower memory scores (-0.165 ± 0.039 SD/SD, Pwave

  11. Field-based landslide susceptibility assessment in a data-scarce environment: the populated areas of the Rwenzori Mountains

    Science.gov (United States)

    Jacobs, Liesbet; Dewitte, Olivier; Poesen, Jean; Sekajugo, John; Nobile, Adriano; Rossi, Mauro; Thiery, Wim; Kervyn, Matthieu

    2018-01-01

    The inhabited zone of the Ugandan Rwenzori Mountains is affected by landslides, frequently causing loss of life, damage to infrastructure and loss of livelihood. This area of ca. 1230 km2 is characterized by contrasting geomorphologic, climatic and lithological patterns, resulting in different landslide types. In this study, the spatial pattern of landslide susceptibility is investigated based on an extensive field inventory constructed for five representative areas within the region (153 km2) and containing over 450 landslides. To achieve a reliable susceptibility assessment, the effects of (1) using different topographic data sources and spatial resolutions and (2) changing the scale of assessment by comparing local and regional susceptibility models on the susceptibility model performances are investigated using a pixel-based logistic regression approach. Topographic data are extracted from different digital elevation models (DEMs) based on radar interferometry (SRTM and TanDEM-X) and optical stereophotogrammetry (ASTER DEM). Susceptibility models using the radar-based DEMs tend to outperform the ones using the ASTER DEM. The model spatial resolution is varied between 10, 20, 30 and 90 m. The optimal resolution depends on the location of the investigated area within the region but the lowest model resolution (90 m) rarely yields the best model performances while the highest model resolution (10 m) never results in significant increases in performance compared to the 20 m resolution. Models built for the local case studies generally have similar or better performances than the regional model and better reflect site-specific controlling factors. At the regional level the effect of distinguishing landslide types between shallow and deep-seated landslides is investigated. The separation of landslide types allows us to improve model performances for the prediction of deep-seated landslides and to better understand factors influencing the occurrence of shallow

  12. Field-based landslide susceptibility assessment in a data-scarce environment: the populated areas of the Rwenzori Mountains

    Directory of Open Access Journals (Sweden)

    L. Jacobs

    2018-01-01

    Full Text Available The inhabited zone of the Ugandan Rwenzori Mountains is affected by landslides, frequently causing loss of life, damage to infrastructure and loss of livelihood. This area of ca. 1230 km2 is characterized by contrasting geomorphologic, climatic and lithological patterns, resulting in different landslide types. In this study, the spatial pattern of landslide susceptibility is investigated based on an extensive field inventory constructed for five representative areas within the region (153 km2 and containing over 450 landslides. To achieve a reliable susceptibility assessment, the effects of (1 using different topographic data sources and spatial resolutions and (2 changing the scale of assessment by comparing local and regional susceptibility models on the susceptibility model performances are investigated using a pixel-based logistic regression approach. Topographic data are extracted from different digital elevation models (DEMs based on radar interferometry (SRTM and TanDEM-X and optical stereophotogrammetry (ASTER DEM. Susceptibility models using the radar-based DEMs tend to outperform the ones using the ASTER DEM. The model spatial resolution is varied between 10, 20, 30 and 90 m. The optimal resolution depends on the location of the investigated area within the region but the lowest model resolution (90 m rarely yields the best model performances while the highest model resolution (10 m never results in significant increases in performance compared to the 20 m resolution. Models built for the local case studies generally have similar or better performances than the regional model and better reflect site-specific controlling factors. At the regional level the effect of distinguishing landslide types between shallow and deep-seated landslides is investigated. The separation of landslide types allows us to improve model performances for the prediction of deep-seated landslides and to better understand factors influencing the

  13. Evidence implicating BRD1 with brain development and susceptibility to both schizophrenia and bipolar affective disorder

    DEFF Research Database (Denmark)

    Severinsen, Jacob; Bjarkam, Carsten; Kiær-Larsen, Stine

    Introduction: Linkage studies suggest that chromosome 22q12-13 may contain one or more shared susceptibility genes for schizophrenia (SZ) and bipolar affective disorder (BPD). In a Faeroese sample we previously reported association between microsatellite markers located at 22q13.31-qtel and both...... disorders. Methods: The present study reports an association analysis across 5 genes (including 14 single nucleotide and two microsatellite polymorphisms) in this interval using a case-control sample of 162 BPD, 103 SZ patients and 200 controls. Results: The bromodomain-containing 1 gene (BRD1), which...... encodes a putative regulator of transcription showed association with both disorders with minimal p-values of 0.0046 and 0.00001 for single marker and overall haplotype analysis, respectively. A specific BRD1 2-marker “risk” haplotype showed a frequency of ~10% in the combined case group versus ~1...

  14. Establishment, characterization, virus susceptibility and transfection of cell lines from cobia, Rachycentron canadum (L.), brain and fin.

    Science.gov (United States)

    Cheng, T-C; Lai, Y-S; Lin, I-Y; Wu, C-P; Chang, S-L; Chen, T-I; Su, M-S

    2010-02-01

    Establishment and characterization of two cobia, Rachycentron canadum, cell lines derived from cobia brain (CB) and cobia fin (CF) are described. Caudal fin and brain from juvenile cobia were dissociated for 30 and 10 min, respectively, in phosphate-buffered saline containing 0.25% trypsin at 25 degrees C. The optimal culture condition for both dissociated cells (primary cell culture) was at 28 degrees C in Leibovitz-15 medium containing 10% foetal bovine serum. The cells have been sub-cultured at a ratio of 1:2 for more than 160 passages over a period of 3 years. Origin of the cultured cells was verified by comparison of their sequences of mitochondrial cytochrome oxidase subunit I genes (cox I) with the cox 1 sequence from cobia muscle tissue. The cell lines showed polyploidy. No mycoplasma contamination was detected. Susceptibility to grouper iridovirus was observed for the CB cell line but not the CF cell line. Both cell lines expressed green fluorescent protein after being transfected with green fluorescent reporter gene driven by the cytomegalovirus promoter.

  15. Imaging and clinical characteristics of children with multiple foci of microsusceptibility changes in the brain on susceptibility-weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Niwa, Tetsu [Kanagawa Children' s Medical Center, Department of Radiology, Yokohama (Japan); University Medical Center Utrecht, Department of Radiology, Heidelberglaan 100, PO Box 85500, Utrecht (Netherlands); Aida, Noriko; Fujita, Kazutoshi; Shishikura, Ayako [Kanagawa Children' s Medical Center, Department of Radiology, Yokohama (Japan); Takahara, Taro; Kwee, Thomas C. [University Medical Center Utrecht, Department of Radiology, Heidelberglaan 100, PO Box 85500, Utrecht (Netherlands); Miyata, Daiki [Kanagawa Children' s Medical Center, Department of Circulation Medicine, Yokohama (Japan); Inoue, Tomio [Yokohama City University, Graduate School of Medicine, Department of Radiology, Yokohama (Japan)

    2010-10-15

    Microsusceptibility changes in the brain are well known to correspond with microbleeds or micrometal fragments in adults, but this phenomenon has not been explored well in children. To assess imaging and clinical characteristics of children with multiple foci of microsusceptibility changes using susceptibility-weighted imaging (SWI). Between 2006 and 2008, 12 children with multiple foci of microsusceptibility on SWI without corresponding abnormal signal on conventional MRI were identified and were retrospectively assessed. The locations of foci of microsusceptibility included the cerebral white matter, basal ganglia, brainstem and cerebellar white matter, without any clear systematic anatomic distribution. CT (n = 5) showed no calcification at the locations corresponding to the microsusceptibility on SWI. Conventional MR imaging showed white matter volume loss (n = 5), delayed myelination (n = 2), acute infarction (n = 1), chronic infarction (n = 1), meningitis (n = 1), slight signal abnormality in the white matter (n = 1) and no abnormal findings (n = 1). Follow-up SWI (n = 3) showed no change of the microsusceptibility foci. Interestingly, all children had a history of heart surgery under extracorporeal circulation for congenital heart disease. Multiple foci of microsusceptibility can be seen in the brain on SWI in children with congenital heart disease who underwent heart surgery with extracorporeal circulation. (orig.)

  16. Regional Susceptibility to Domoic Acid in Primary Astrocyte Cells Cultured from the Brain Stem and Hippocampus

    Directory of Open Access Journals (Sweden)

    Olga M. Pulido

    2008-02-01

    Full Text Available Domoic acid is a marine biotoxin associated with harmful algal blooms and is the causative agent of amnesic shellfish poisoning in marine animals and humans. It is also an excitatory amino acid analog to glutamate and kainic acid which acts through glutamate receptors eliciting a very rapid and potent neurotoxic response. The hippocampus, among other brain regions, has been identified as a specific target site having high sensitivity to DOM toxicity. Histopathology evidence indicates that in addition to neurons, the astrocytes were also injured. Electron microscopy data reported in this study further supports the light microscopy findings. Furthermore, the effect of DOM was confirmed by culturing primary astrocytes from the hippocampus and the brain stem and subsequently exposing them to domoic acid. The RNA was extracted and used for biomarker analysis. The biomarker analysis was done for the early response genes including c-fos, c-jun, c-myc, Hsp-72; specific marker for the astrocytes- GFAP and the glutamate receptors including GluR 2, NMDAR 1, NMDAR 2A and B. Although, the astrocyte-GFAP and c-fos were not affected, c-jun and GluR 2 were down-regulated. The microarray analysis revealed that the chemokines / cytokines, tyrosine kinases (Trk, and apoptotic genes were altered. The chemokines that were up-regulated included - IL1-a, IL-1B, IL-6, the small inducible cytokine, interferon protein IP-10, CXC chemokine LIX, and IGF binding proteins. The Bax, Bcl-2, Trk A and Trk B were all downregulated. Interestingly, only the hippocampal astrocytes were affected. Our findings suggest that astrocytes may present a possible target for pharmacological interventions for the prevention and treatment of amnesic shellfish poisoning and for other brain pathologies involving excitotoxicity

  17. Estimation of the susceptibility at erosion and desertification in wet areas with VNIR radiometry

    International Nuclear Information System (INIS)

    Cordoba-Sola, P.; Navarro-Pedreno, J.; Gomez-Lucas, I.; Mataix-Beneyto, J.

    2009-01-01

    A multispectral technology as tool for assessing the susceptibility to erosion and desertification in humid zones from the European Mediterranean was applied by means of the use of spectral reflectance data to determine the contents of different attributes of the soils. A collection of field electromagnetic spectrums were obtained from 25 covers of soil, a derivative analysis was applied to electromagnetic spectrums and finally a PCS was made. The results showed good correlations (R 2 >0,5) between properties of soil and electromagnetic spectrum, therefore it is possible to determine the content of these soil attributes with spectral analysis, which minimizes cost and time. (Author) 8 refs.

  18. Sleep deprivation does not affect neuronal susceptibility to mild traumatic brain injury in the rat

    Directory of Open Access Journals (Sweden)

    Caron AM

    2015-06-01

    Full Text Available Aimee M Caron, Richard Stephenson Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada Abstract: Mild and moderate traumatic brain injuries (TBIs (and concussion occur frequently as a result of falls, automobile accidents, and sporting activities, and are a major cause of acute and chronic disability. Fatigue and excessive sleepiness are associated with increased risk of accidents, but it is unknown whether prior sleep debt also affects the pathophysiological outcome of concussive injury. Using the “dark neuron” (DN as a marker of reversible neuronal damage, we tested the hypothesis that acute (48 hours total sleep deprivation (TSD and chronic sleep restriction (CSR; 10 days, 6-hour sleep/day affect DN formation following mild TBI in the rat. TSD and CSR were administered using a walking wheel apparatus. Mild TBI was administered under anesthesia using a weight-drop impact model, and the acute neuronal response was observed without recovery. DNs were detected using standard bright-field microscopy with toluidine blue stain following appropriate tissue fixation. DN density was low under home cage and sleep deprivation control conditions (respective median DN densities, 0.14% and 0.22% of neurons, and this was unaffected by TSD alone (0.1%. Mild TBI caused significantly higher DN densities (0.76%, and this was unchanged by preexisting acute or chronic sleep debt (TSD, 0.23%; CSR, 0.7%. Thus, although sleep debt may be predicted to increase the incidence of concussive injury, the present data suggest that sleep debt does not exacerbate the resulting neuronal damage. Keywords: sleep deprivation, concussion, traumatic brain injury, dark neuron, neurodegeneration, rat cortex

  19. Integrated SSFP for functional brain mapping at 7 T with reduced susceptibility artifact

    Science.gov (United States)

    Sun, Kaibao; Xue, Rong; Zhang, Peng; Zuo, Zhentao; Chen, Zhongwei; Wang, Bo; Martin, Thomas; Wang, Yi; Chen, Lin; He, Sheng; Wang, Danny J. J.

    2017-03-01

    Balanced steady-state free precession (bSSFP) offers an alternative and potentially important tool to the standard gradient-echo echo-planar imaging (GE-EPI) for functional MRI (fMRI). Both passband and transition band based bSSFP have been proposed for fMRI. The applications of these methods, however, are limited by banding artifacts due to the sensitivity of bSSFP signal to off-resonance effects. In this article, a unique case of the SSFP-FID sequence, termed integrated-SSFP or iSSFP, was proposed to overcome the obstacle by compressing the SSFP profile into the width of a single voxel. The magnitude of the iSSFP signal was kept constant irrespective of frequency shift. Visual stimulation studies were performed to demonstrate the feasibility of fMRI using iSSFP at 7 T with flip angles of 4° and 25°, compared to standard bSSFP and gradient echo (GRE) imaging. The signal changes for the complex iSSFP signal in activated voxels were 2.48 ± 0.53 (%) and 2.96 ± 0.87 (%) for flip angles (FA) of 4° and 25° respectively at the TR of 9.88 ms. Simultaneous multi-slice acquisition (SMS) with the CAIPIRIHNA technique was carried out with iSSFP scanning to detect the anterior temporal lobe activation using a semantic processing task fMRI, compared with standard 2D GE-EPI. This study demonstrates the feasibility of iSSFP for fMRI with reduced susceptibility artifacts, while maintaining robust functional contrast at 7 T.

  20. Brain areas and pathways in the regulation of glucose metabolism

    NARCIS (Netherlands)

    Diepenbroek, Charlene; Serlie, Mireille J.; Fliers, Eric; Kalsbeek, Andries; la Fleur, Susanne E.

    2013-01-01

    Glucose is the most important source of fuel for the brain and its concentration must be kept within strict boundaries to ensure the organism's optimal fitness. To maintain glucose homeostasis, an optimal balance between glucose uptake and glucose output is required. Besides managing acute changes

  1. The Corpus Callosum Area and Brain Volume in Alzheimer's Disease, Mild Cognitive Impairment and Healthy Controls

    International Nuclear Information System (INIS)

    Choi, Hee Seok; Kim, Kwang Ki; Yoon, Yup Yoon; Seo, Hyung Suk

    2009-01-01

    To compare the corpus callosum (CC) area and brain volume among individuals with Alzheimer's disease (AD), mild cognitive impairment (MCI) and healthy controls (HC). To evaluate the relationship of CC area and brain volume in 111 subjects (M:F = 48:63; mean age, 56.9 years) without memory disturbance and 28 subjects (11:17; 66.7years) with memory disturbance. The 11 AD (3:8; 75.7 years), 17 MCI (8:9; 60.9 years) and 28 selected HC (11:17; 66.4 years) patients were investigated for comparison of their CC area and brain volume. A good positive linear correlation was found between CC area and brain volume in subjects without and with memory disturbance (r = 0.64 and 0.66, respectively, p 2 , 715.4 ± 107 cm3) were significantly smaller than in MCI patients (595.9 ± 108, 844.1 ± 85) and the HCs (563.2 ± 75, 818.9 ± 109) (p < 0.05). The CC area and brain volume were not significantly different between MCI patients and the HCs. The CC area was significantly correlated with brain volume. Both CC area and brain volume were significantly smaller in the AD patients

  2. Landslide susceptibility modeling applying machine learning methods: A case study from Longju in the Three Gorges Reservoir area, China

    Science.gov (United States)

    Zhou, Chao; Yin, Kunlong; Cao, Ying; Ahmed, Bayes; Li, Yuanyao; Catani, Filippo; Pourghasemi, Hamid Reza

    2018-03-01

    Landslide is a common natural hazard and responsible for extensive damage and losses in mountainous areas. In this study, Longju in the Three Gorges Reservoir area in China was taken as a case study for landslide susceptibility assessment in order to develop effective risk prevention and mitigation strategies. To begin, 202 landslides were identified, including 95 colluvial landslides and 107 rockfalls. Twelve landslide causal factor maps were prepared initially, and the relationship between these factors and each landslide type was analyzed using the information value model. Later, the unimportant factors were selected and eliminated using the information gain ratio technique. The landslide locations were randomly divided into two groups: 70% for training and 30% for verifying. Two machine learning models: the support vector machine (SVM) and artificial neural network (ANN), and a multivariate statistical model: the logistic regression (LR), were applied for landslide susceptibility modeling (LSM) for each type. The LSM index maps, obtained from combining the assessment results of the two landslide types, were classified into five levels. The performance of the LSMs was evaluated using the receiver operating characteristics curve and Friedman test. Results show that the elimination of noise-generating factors and the separated modeling of each landslide type have significantly increased the prediction accuracy. The machine learning models outperformed the multivariate statistical model and SVM model was found ideal for the case study area.

  3. Mechanism and Therapy for the Shared Susceptibility to Migraine and Epilepsy after Traumatic Brain Injury (TBI)

    Science.gov (United States)

    2013-10-01

    and 7 days post injury time point. Figure 20 shows the typical lesion pattern following our protocol. Figure 21 shows Nissl stain at different...diameter. Figure 21. Light microscopy images of Nissl stain displaying lesion area 1 week following impact in WT (Stat3-LoxP) and KO (Stat3-LoxP-Cre...cryoprotectant solution pending further processing. Every third section was collected to quantify infarct volumes using cresyl violet ( Nissl ) stain (Ohab et

  4. Brain size and white matter content of cerebrospinal tracts determine the upper cervical cord area: evidence from structural brain MRI

    Energy Technology Data Exchange (ETDEWEB)

    Engl, Christina; Arsic, Milan; Boucard, Christine C.; Biberacher, Viola; Nunnemann, Sabine; Muehlau, Mark [Technische Universitaet Muenchen, Department of Neurology, Klinikum rechts der Isar, Munich (Germany); Technische Universitaet Muenchen, TUM-Neuroimaging Center, Klinikum rechts der Isar, Munich (Germany); Schmidt, Paul [Technische Universitaet Muenchen, Department of Neurology, Klinikum rechts der Isar, Munich (Germany); Ludwig-Maximilians-University Muenchen, Department of Statistics, Munich (Germany); Roettinger, Michael [Technische Universitaet Muenchen, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); Muenchner Institut fuer Neuroradiologie, Munich (Germany); Etgen, Thorleif [Technische Universitaet Muenchen, Department of Neurology, Klinikum rechts der Isar, Munich (Germany); Klinikum Traunstein, Department of Neurology, Traunstein (Germany); Koutsouleris, Nikolaos; Meisenzahl, Eva M. [Ludwig-Maximilians-Universitaet Muenchen, Department of Psychiatry and Psychotherapy, Munich (Germany); Reiser, Maximilian [Ludwig-Maximilians-Universitaet, Department of Radiology, Munich (Germany)

    2013-08-15

    Measurement of the upper cervical cord area (UCCA) from brain MRI may be an effective way to quantify spinal cord involvement in neurological disorders such as multiple sclerosis. However, knowledge on the determinants of UCCA in healthy controls (HCs) is limited. In two cohorts of 133 and 285 HCs, we studied the influence of different demographic, body-related, and brain-related parameters on UCCA by simple and partial correlation analyses as well as by voxel-based morphometry (VBM) across both cerebral gray matter (GM) and white matter (WM). First, we confirmed the known but moderate effect of age on UCCA in the older cohort. Second, we studied the correlation of UCCA with sex, body height, and total intracranial volume (TIV). TIV was the only variable that correlated significantly with UCCA after correction for the other variables. Third, we studied the correlation of UCCA with brain-related parameters. Brain volume correlated stronger with UCCA than TIV. Both volumes of the brain tissue compartments GM and WM correlated with UCCA significantly. WM volume explained variance of UCCA after correction for GM volume, whilst the opposite was not observed. Correspondingly, VBM did not yield any brain region, whose GM content correlated significantly with UCCA, whilst cerebral WM content of cerebrospinal tracts strongly correlated with UCCA. This latter effect increased along a craniocaudal gradient. UCCA is mainly determined by brain volume as well as by WM content of cerebrospinal tracts. (orig.)

  5. Landslide susceptibility assessment using Spatial Analysis and GIS modeling in Cluj-Napoca Metropolitan Area, Romania

    Directory of Open Access Journals (Sweden)

    Bogdan Eugen Dolean

    2017-06-01

    Full Text Available In Romania, landslides together with the multitude geomorphological processes linked to them are some of the most common hazards which manifested in vulnerable areas with important human activities can induce many negative effects. From this perspective, identifying the areas affected by landslides, based on GIS spatial analysis models and statistical methods, is a subject frequently discussed in the national and international literature. This research was focused on the methods and practices of GIS spatial analysis, with a target of creating a complex model and a viable methodology of assessment the probability of occurrence of landslides, applicable within any territory. The study was based on the identification and analysis in a bivariate systemic manner of the numerous factors involved in the production of landslides, such as topography, morphology, hydrography, geological, lithology, weather, land use. The area in which the analysis has been conducted, The Metropolitan Area of Cluj-Napoca, was chosen due to the exacerbated urbanization of the recent years, coupled with a massive increase in the number of inhabitants, thus being a space of socioeconomic importance and a real challenge regarding spatial planning. Applying the model in this area has generated relatively good results, with a power of predictability of over 80%, measured in landslides sample areas used for the validation of the results, fact which attest the viability of the model and the fact that the model can be used in different areas with related morphometric and environmental characteristics.

  6. A GIS-based statistical model for rapid landslide susceptibility mapping in the Beichuan-Pingwu area, Sichuan, China

    International Nuclear Information System (INIS)

    Chen, Y; Wang, Q J

    2014-01-01

    The 2008 Wenchuan earthquake, with a magnitude of Mw 8.0, induced numerous landslides. Remote sensing planes were sent out to take high resolution aerial photographs, from which the geologic hazards could be instantly interpreted. However, aerial images covering all of the study area could not be obtained in a short time because of the limitations of the planes and the influence of weather conditions. This studyestablishes a statistical model based on the landslide interpretation results of one photographic strip inside the Beichuan-Pingwu area. It has strong applicability and can be applied to other places without such data. Finally, we produced a landslide susceptibility map, which providesscientific support for the instant evaluation of disaster information and post-disaster reconstruction

  7. Nonspatial intermodal selective attention is mediated by sensory brain brain areas: Evidence from event-related potential.

    NARCIS (Netherlands)

    Talsma, D.; Kok, A.

    2001-01-01

    Focuses on the question of whether inter-and intramodal forms of attention are reflected in activation of the same or different brain areas. ERPs were recorded while Ss (aged 18-41 yrs) were presented a random sequence of visual and auditory stimuli. They were instructed to attend to nonspatial

  8. 7-Tesla Susceptibility-Weighted Imaging to Assess the Effects of Radiotherapy on Normal-Appearing Brain in Patients With Glioma

    International Nuclear Information System (INIS)

    Lupo, Janine M.; Chuang, Cynthia F.; Chang, Susan M.; Barani, Igor J.; Jimenez, Bert; Hess, Christopher P.; Nelson, Sarah J.

    2012-01-01

    Purpose: To evaluate the intermediate- and long-term imaging manifestations of radiotherapy on normal-appearing brain tissue in patients with treated gliomas using 7T susceptibility-weighted imaging (SWI). Methods and Materials: SWI was performed on 25 patients with stable gliomas on a 7 Tesla magnet. Microbleeds were identified as discrete foci of susceptibility that did not correspond to vessels. The number of microbleeds was counted within and outside of the T2-hyperintense lesion. For 3 patients, radiation dosimetry maps were reconstructed and fused with the 7T SWI data. Results: Multiple foci of susceptibility consistent with microhemorrhages were observed in patients 2 years after chemoradiation. These lesions were not present in patients who were not irradiated. The prevalence of microhemorrhages increased with the time since completion of radiotherapy, and these lesions often extended outside the boundaries of the initial high-dose volume and into the contralateral hemisphere. Conclusions: High-field SWI has potential for visualizing the appearance of microbleeds associated with long-term effects of radiotherapy on brain tissue. The ability to visualize these lesions in normal-appearing brain tissue may be important in further understanding the utility of this treatment in patients with longer survival.

  9. Deep brain stimulation affects conditioned and unconditioned anxiety in different brain areas

    NARCIS (Netherlands)

    van Dijk, A.; Klanker, M.; van Oorschot, N.; Post, R.; Hamelink, R.; Feenstra, M. G. P.; Denys, D.

    2013-01-01

    Deep brain stimulation (DBS) of the nucleus accumbens (NAc) has proven to be an effective treatment for therapy refractory obsessive compulsive disorder. Clinical observations show that anxiety symptoms decrease rapidly following DBS. As in clinical studies different regions are targeted, it is of

  10. A study of perifocal low-density area in metastatic brain tumor

    International Nuclear Information System (INIS)

    Suzuki, Ryuta; Okada, Kodai; Hiratsuka, Hideo; Inaba, Yutaka; Tsuyumu, Matsutaira.

    1980-01-01

    It is well known that vasogenic brain edema often develops in brain tumors, head injuries, and inflammatory brain lesions. In order to investigate the development and resolution of vasogenic brain edema, some CT findings of metastatic brain tumors were studied in detail. 20 cases of metastatic brain tumors of the past three years were examined by means of a CT scan. In almost all the cases there was a perifocal low-density area (PFL) in the CT findings. In the tumors which were cystic and/or located in the infratentorial space, PFL was not present or, if present, only slightly so. On the contrary, in the tumors which were nodular and/or in the supratentorial space, PFL was present extensively. In the supratentorial metastasis, PFL seemed to be restricted within the white matter and not to involve the gray matter nor such midline structures as basal ganglia and corpus callosum. Besides, PFL was always in contact with the lateral ventricular wall. These results show that PFL in the metastatic tumors resembles in shape the experimental cold-induced brain edema in cats. PFL is presumed to represent vasogenic brain edema; these findings support the hypothesis that the main mechanism of the resolution of vasogenic brain edema is the drainage of the edema fluid into the ventricular CSF. (author)

  11. Study of perifocal low-density area in metastatic brain tumor

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, R; Okada, K; Hiratsuka, H; Inaba, Y [Tokyo Medical and Dental Univ. (Japan). School of Medicine; Tsuyumu, M

    1980-04-01

    It is well known that vasogenic brain edema often develops in brain tumors, head injuries, and inflammatory brain lesions. In order to investigate the development and resolution of vasogenic brain edema, some CT findings of metastatic brain tumors were studied in detail. 20 cases of metastatic brain tumors of the past three years were examined by means of a CT scan. In almost all the cases there was a perifocal low-density area (PFL) in the CT findings. In the tumors which were cystic and/or located in the infratentorial space, PFL was not present or, if present, only slightly so. On the contrary, in the tumors which were nodular and/or in the supratentorial space, PFL was present extensively. In the supratentorial metastasis, PFL seemed to be restricted within the white matter and not to involve the gray matter nor such midline structures as basal ganglia and corpus callosum. Besides, PFL was always in contact with the lateral ventricular wall. These results show that PFL in the metastatic tumors resembles in shape the experimental cold-induced brain edema in cats. PFL is presumed to represent vasogenic brain edema; these findings support the hypothesis that the main mechanism of the resolution of vasogenic brain edema is the drainage of the edema fluid into the ventricular CSF.

  12. One century of brain mapping using Brodmann areas.

    Science.gov (United States)

    Strotzer, Michael

    2009-08-01

    100 years after their publication, Brodmann's maps of the cerebral cortex are universally used to locate neuropsychological functions. On the occasion of this jubilee the life and work of Korbinian Brodmann are reported. The core functions of each single Brodmann area are described and Brodmann's views on neuropsychological processes are depicted.

  13. Naturalizing aesthetics: brain areas for aesthetic appraisal across sensory modalities.

    Science.gov (United States)

    Brown, Steven; Gao, Xiaoqing; Tisdelle, Loren; Eickhoff, Simon B; Liotti, Mario

    2011-09-01

    We present here the most comprehensive analysis to date of neuroaesthetic processing by reporting the results of voxel-based meta-analyses of 93 neuroimaging studies of positive-valence aesthetic appraisal across four sensory modalities. The results demonstrate that the most concordant area of activation across all four modalities is the right anterior insula, an area typically associated with visceral perception, especially of negative valence (disgust, pain, etc.). We argue that aesthetic processing is, at its core, the appraisal of the valence of perceived objects. This appraisal is in no way limited to artworks but is instead applicable to all types of perceived objects. Therefore, one way to naturalize aesthetics is to argue that such a system evolved first for the appraisal of objects of survival advantage, such as food sources, and was later co-opted in humans for the experience of artworks for the satisfaction of social needs. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Stress corrosion cracking susceptibility of steam generator tubing on secondary side in restricted flow areas

    International Nuclear Information System (INIS)

    Fulger, M.; Lucan, D.; Radulescu, M.; Velciu, L.

    2003-01-01

    Nuclear steam generator tubes operate in high temperature water and on the secondary side in restricted flow areas many nonvolatile impurities accidentally introduced into circuit tend to concentrate. The concentration process leads to the formation of highly aggressive alkaline or acid solutions in crevices, and these solutions can cause stress corrosion cracking (SCC) on stressed tube materials. Even though alloy 800 has shown to be highly resistant to general corrosion in high temperature water, it has been found that the steam generator tubes may crack during service from the primary and/or secondary side. Stress corrosion cracking is still a serious problem occurring on outside tubes in operating steam generators. The purpose of this study was to evaluate the environmental factors affecting the stress corrosion cracking of steam generators tubing. The main test method was the exposure for 1000 hours into static autoclaves of plastically stressed C-rings of Incoloy 800 in caustic solutions (10% NaOH) and acidic chloride solutions because such environments may sometimes form accidentally in crevices on secondary side of tubes. Because the kinetics of corrosion of metals is indicated by anodic polarization curves, in this study, some stressed specimens were anodically polarized in caustic solutions in electrochemical cell, and other in chloride acidic solutions. The results presented as micrographs, potentiokinetic curves, and electrochemical parameters have been compared to establish the SCC behavior of Incoloy 800 in such concentrated environments. (authors)

  15. [Brodmann Areas 17, 18, and 19 in the Human Brain: An Overview].

    Science.gov (United States)

    Kawachi, Juro

    2017-04-01

    Brodmann areas 17, 18, and 19 in the human brain are visual cortices of the occipital lobe. Each area has its own retinotopic representations, particulary area 19, which has many small retinotopic areas representing half or all of the contralateral visual field, several functional areas, and nine cytoarchitectonic areas. Several fasciculi are known as occipital fiber connections, but their precise endpoints are not clear. Lesions in the visual cortices cause several visual disorders including visual field defect, visual hallucinations, metamorphopsia, and different kinds of visual agnosia.

  16. Alterations of whole-brain cortical area and thickness in mild cognitive impairment and Alzheimer's disease.

    Science.gov (United States)

    Li, Chuanming; Wang, Jian; Gui, Li; Zheng, Jian; Liu, Chen; Du, Hanjian

    2011-01-01

    Gray matter volume and density of several brain regions, determined by magnetic resonance imaging (MRI), are decreased in Alzheimer's disease (AD). Animal studies have indicated that changes in cortical area size is relevant to thinking and behavior, but alterations of cortical area and thickness in the brains of individuals with AD or its likely precursor, mild cognitive impairment (MCI), have not been reported. In this study, 25 MCI subjects, 30 AD subjects, and 30 age-matched normal controls were recruited for brain MRI scans and Functional Activities Questionnaire (FAQ) assessments. Based on the model using FreeSurfer software, two brain lobes were divided into various regions according to the Desikan-Killiany atlas and the cortical area and thickness of every region was compared and analyzed. We found a significant increase in cortical area of several regions in the frontal and temporal cortices, which correlated negatively with MMSE scores, and a significant decrease in cortical area of several regions in the parietal cortex and the cingulate gyrus in AD subjects. Increased cortical area was also seen in some regions of the frontal and temporal cortices in MCI subjects, whereas the cortical thickness of the same regions was decreased. Our observations suggest characteristic differences of the cortical area and thickness in MCI, AD, and normal control subjects, and these changes may help diagnose both MCI and AD.

  17. Drug susceptibility of Mycobacterium tuberculosis in a rural area of Bangladesh and its relevance to the national treatment regimens.

    Science.gov (United States)

    Van Deun, A; Aung, K J; Chowdhury, S; Saha, S; Pankaj, A; Ashraf, A; Rigouts, L; Fissette, K; Portaels, F

    1999-02-01

    Greater Mymensingh District, a rural area of Bangladesh, at the start of the National Tuberculosis Programme (NTP). To determine the prevalence of initial and acquired drug resistance of Mycobacterium tuberculosis, and to assess the appropriateness of the NTP's standard regimens. Sampling of pre-treatment sputum from all newly registered smear-positive cases in five centres covering the area. Culture and susceptibility testing in a supra-national reference laboratory. Initial resistance to isoniazid (H) was 5.4%, and to rifampicin (R) 0.5%. Acquired H and R resistance were 25.9% and 7.4%, respectively. Multidrug resistance (MDR) was observed in one new case only and in 5.6% of previously treated patients. Changing the present NTP indication for retreatment regimen to one month of previous H intake would increase coverage of H-resistant cases from 52% to 89%, adding 6% to drug costs. The prevalence of drug resistance is surprisingly low in Bangladesh, but could rise with improving economic conditions. The NTP regimens for smear-positive cases are appropriate, all the more so since the human immunodeficiency virus is virtually absent. Indications for the retreatment regimen should be extended to include all patients treated for at least one month with any drug. The NTP regimen for smear-negative cases runs the risk of leading to MDR under present field conditions.

  18. Diffusion tensor tractography of language functional areas and fiber pathways in normal human brain

    International Nuclear Information System (INIS)

    Sun Xuejin; Dai Jianping; Chen Hongyan; Gao Peiyi; Ai Lin; Tian Shengyong; Pang Ruilin

    2007-01-01

    Objective: To demonstrate the fiber pathways of Broca area to the other functional brain areas with diffusion tensor imaging and fiber tracking. Methods: Conventionality MRI, diffusion tensor imaging (DTI) and fiber tracking were performed using 3.0 T MRI in 20 healthy person. The fiber bundles and tracts were analyzed in Broca area and contralateral normal area. Results: The left-side fiber bundles were 428 and the right-side were 416 in B45 area, there were no statistically significant differences between both sides (t=0.216, P>0.05). The left-side fiber bundles were 432 and the right-side were 344 in B44 area,there were statistically significant (t=2.314, P 0.05). Differences of the arcuate fascicule between both sides were not statistically significant (t=-0.465, P>0.05), the mean FA on the left was higher than the right (t=1.912, P<0.05). DTI and fiber tracking exhibited that the fiber bundles from Broca area were distributed superoanteriorly to the lateral foreside of the frontal lobe, lateroinferiorly to the occipital lobe through external capsule, and went down through globus pallidus and internal capsule. Conclusion: The fiber tracts bewteen Broca area and other brain areas were the fundamental structures for performing language function of the human brain. (authors)

  19. Determination of hyperactive areas of Cortex Cerebri with using brain SPECT study

    International Nuclear Information System (INIS)

    Stepien, A.; Pawlus, J.; Wasilewska-Radwanska, M.

    2004-01-01

    The aim of this study was the assessment of the ability to apply of SPECT technique to determination of hyperactive areas of cortex cerebri. Analysis included 50 patients (mean aged 44 - 58). Brain SPECT scanning was performed after 1 hour after the intravenous injection of 740 MBq of ethylcisteinate dimmer labeled 99m Technetium (99mTc-ECD) with the use one-head gamma camera with a low-energy, ultra-high resolution collimator. Qualitative and quantitative analysis was performed using specialised software. In 20 cases normal biodistribution of the radiotracer was observed (hyperactive areas in cerebellum and occiput). In patients with psychiatric and neurological disturbances hyperactive areas were visualized in 25 cases in temporal lobes, in 4 cases in parietal lobes and in 1 patient in frontal area and basal ganglia. It is concluded that a number of factors limit the wide-scale use of SPECT, including the sophistication of imaging equipment (single-head cameras are inferior to the newer multihead units) and the experience of the physicians interpreting the scans and utilizing the data. In many diseases physicians do not know which areas of the patient's brain according disorders. Brain SPECT study can be a very useful tool to evaluation of hyperactive areas of cortex cerebri. This technique visualization of cortex cerebri completes standard analysis of disorders of brain activity

  20. [Study on corresponding areas the liver and lung channels in brain with fMRI].

    Science.gov (United States)

    Xu, Fang-Ming; Xie, Peng; Lü, Fa-Jin; Mou, Jun; Li, Yong-Mei; Zhao, Jian-Nong; Chen, Wei-Juan; Gong, Qi-Yong; Zhao, Li-Bo; Liu, Qing-Jun; Shen, Lin; Zhai, Hong; Yang, De-Yu

    2007-10-01

    To explore distribution of the Liver and Lung Channels in the brain so as to provide imaging basis for construction of channel theory in the brain. Sixty healthy student volunteers were randomly divided into a Liver Channel group (I) and a Lung Channel group (II), and the each group was further divided into five subgroups with 6 volunteers in each subgroup, based on five-shu-point principles which, were Dadun (LR 1, I 1), Xingjian (LR 2, I 2), Taichong (LR 3, I 3), Zhongfeng (LR 4, I 4), Ququan (LR 8, I 5), Shaoshang (LU 11, II 1), Yuji (LU 10, II 2), Taiyuan (LU 9, II 3), Jingqu (LU 8, II 4), and Chize (LU 5, II 5), respectively. In order to observe the brain activating patterns during acupuncture at the different acupoints, functional magnetic resonance imaging (fMRI) technique was adopted. All image data were then analyzed with SPM 2 software. The statistical parameter gram was composed of the pixel P areas, and the commonly activated area of five-shu-point of each channel was considered as the brain distribution of the Liver and Lung Channels. The common areas activated by the five-shu-points of the Liver Channel were homolateral Brodmann area (BA) 34, BA 47, red nucleus, contralateral BA 19, BA 30, BA 39, the superior parietal lobule, cerebellum decline, and bilateral BA 3 and culmen. The common areas activated by the five-shu-points of the Lung Channels included homolateral BA 2, BA 18, BA 35, and contralateral BA 9 and substania nigra. There are relatively specific corresponding brain areas for the Liver and Lung Channels, indicating that there is possible relatively specific connection between channels and the brain.

  1. Strong Functional Connectivity among Homotopic Brain Areas Is Vital for Motor Control in Unilateral Limb Movement

    Directory of Open Access Journals (Sweden)

    Pengxu Wei

    2017-07-01

    Full Text Available The mechanism underlying brain region organization for motor control in humans remains poorly understood. In this functional magnetic resonance imaging (fMRI study, right-handed volunteers were tasked to maintain unilateral foot movements on the right and left sides as consistently as possible. We aimed to identify the similarities and differences between brain motor networks of the two conditions. We recruited 18 right-handed healthy volunteers aged 25 ± 2.3 years and used a whole-body 3T system for magnetic resonance (MR scanning. Image analysis was performed using SPM8, Conn toolbox and Brain Connectivity Toolbox. We determined a craniocaudally distributed, mirror-symmetrical modular structure. The functional connectivity between homotopic brain areas was generally stronger than the intrahemispheric connections, and such strong connectivity led to the abovementioned modular structure. Our findings indicated that the interhemispheric functional interaction between homotopic brain areas is more intensive than the interaction along the conventional top–down and bottom–up pathways within the brain during unilateral limb movement. The detected strong interhemispheric horizontal functional interaction is an important aspect of motor control but often neglected or underestimated. The strong interhemispheric connectivity may explain the physiological phenomena and effects of promising therapeutic approaches. Further accurate and effective therapeutic methods may be developed on the basis of our findings.

  2. The CLAIR model: Extension of Brodmann areas based on brain oscillations and connectivity.

    Science.gov (United States)

    Başar, Erol; Düzgün, Aysel

    2016-05-01

    Since the beginning of the last century, the localization of brain function has been represented by Brodmann areas, maps of the anatomic organization of the brain. They are used to broadly represent cortical structures with their given sensory-cognitive functions. In recent decades, the analysis of brain oscillations has become important in the correlation of brain functions. Moreover, spectral connectivity can provide further information on the dynamic connectivity between various structures. In addition, brain responses are dynamic in nature and structural localization is almost impossible, according to Luria (1966). Therefore, brain functions are very difficult to localize; hence, a combined analysis of oscillation and event-related coherences is required. In this study, a model termed as "CLAIR" is described to enrich and possibly replace the concept of the Brodmann areas. A CLAIR model with optimum function may take several years to develop, but this study sets out to lay its foundation. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  3. Strong Functional Connectivity among Homotopic Brain Areas Is Vital for Motor Control in Unilateral Limb Movement.

    Science.gov (United States)

    Wei, Pengxu; Zhang, Zuting; Lv, Zeping; Jing, Bin

    2017-01-01

    The mechanism underlying brain region organization for motor control in humans remains poorly understood. In this functional magnetic resonance imaging (fMRI) study, right-handed volunteers were tasked to maintain unilateral foot movements on the right and left sides as consistently as possible. We aimed to identify the similarities and differences between brain motor networks of the two conditions. We recruited 18 right-handed healthy volunteers aged 25 ± 2.3 years and used a whole-body 3T system for magnetic resonance (MR) scanning. Image analysis was performed using SPM8, Conn toolbox and Brain Connectivity Toolbox. We determined a craniocaudally distributed, mirror-symmetrical modular structure. The functional connectivity between homotopic brain areas was generally stronger than the intrahemispheric connections, and such strong connectivity led to the abovementioned modular structure. Our findings indicated that the interhemispheric functional interaction between homotopic brain areas is more intensive than the interaction along the conventional top-down and bottom-up pathways within the brain during unilateral limb movement. The detected strong interhemispheric horizontal functional interaction is an important aspect of motor control but often neglected or underestimated. The strong interhemispheric connectivity may explain the physiological phenomena and effects of promising therapeutic approaches. Further accurate and effective therapeutic methods may be developed on the basis of our findings.

  4. Loud Noise Exposure Produces DNA, Neurotransmitter and Morphological Damage within Specific Brain Areas

    Directory of Open Access Journals (Sweden)

    Giada Frenzilli

    2017-06-01

    Full Text Available Exposure to loud noise is a major environmental threat to public health. Loud noise exposure, apart from affecting the inner ear, is deleterious for cardiovascular, endocrine and nervous systems and it is associated with neuropsychiatric disorders. In this study we investigated DNA, neurotransmitters and immune-histochemical alterations induced by exposure to loud noise in three major brain areas (cerebellum, hippocampus, striatum of Wistar rats. Rats were exposed to loud noise (100 dBA for 12 h. The effects of noise on DNA integrity in all three brain areas were evaluated by using Comet assay. In parallel studies, brain monoamine levels and morphology of nigrostriatal pathways, hippocampus and cerebellum were analyzed at different time intervals (24 h and 7 days after noise exposure. Loud noise produced a sudden increase in DNA damage in all the brain areas under investigation. Monoamine levels detected at 7 days following exposure were differently affected depending on the specific brain area. Namely, striatal but not hippocampal dopamine (DA significantly decreased, whereas hippocampal and cerebellar noradrenaline (NA was significantly reduced. This is in line with pathological findings within striatum and hippocampus consisting of a decrease in striatal tyrosine hydroxylase (TH combined with increased Bax and glial fibrillary acidic protein (GFAP. Loud noise exposure lasting 12 h causes immediate DNA, and long-lasting neurotransmitter and immune-histochemical alterations within specific brain areas of the rat. These alterations may suggest an anatomical and functional link to explain the neurobiology of diseases which prevail in human subjects exposed to environmental noise.

  5. A Combination of Geographically Weighted Regression, Particle Swarm Optimization and Support Vector Machine for Landslide Susceptibility Mapping: A Case Study at Wanzhou in the Three Gorges Area, China

    Directory of Open Access Journals (Sweden)

    Xianyu Yu

    2016-05-01

    Full Text Available In this study, a novel coupling model for landslide susceptibility mapping is presented. In practice, environmental factors may have different impacts at a local scale in study areas. To provide better predictions, a geographically weighted regression (GWR technique is firstly used in our method to segment study areas into a series of prediction regions with appropriate sizes. Meanwhile, a support vector machine (SVM classifier is exploited in each prediction region for landslide susceptibility mapping. To further improve the prediction performance, the particle swarm optimization (PSO algorithm is used in the prediction regions to obtain optimal parameters for the SVM classifier. To evaluate the prediction performance of our model, several SVM-based prediction models are utilized for comparison on a study area of the Wanzhou district in the Three Gorges Reservoir. Experimental results, based on three objective quantitative measures and visual qualitative evaluation, indicate that our model can achieve better prediction accuracies and is more effective for landslide susceptibility mapping. For instance, our model can achieve an overall prediction accuracy of 91.10%, which is 7.8%–19.1% higher than the traditional SVM-based models. In addition, the obtained landslide susceptibility map by our model can demonstrate an intensive correlation between the classified very high-susceptibility zone and the previously investigated landslides.

  6. A Combination of Geographically Weighted Regression, Particle Swarm Optimization and Support Vector Machine for Landslide Susceptibility Mapping: A Case Study at Wanzhou in the Three Gorges Area, China.

    Science.gov (United States)

    Yu, Xianyu; Wang, Yi; Niu, Ruiqing; Hu, Youjian

    2016-05-11

    In this study, a novel coupling model for landslide susceptibility mapping is presented. In practice, environmental factors may have different impacts at a local scale in study areas. To provide better predictions, a geographically weighted regression (GWR) technique is firstly used in our method to segment study areas into a series of prediction regions with appropriate sizes. Meanwhile, a support vector machine (SVM) classifier is exploited in each prediction region for landslide susceptibility mapping. To further improve the prediction performance, the particle swarm optimization (PSO) algorithm is used in the prediction regions to obtain optimal parameters for the SVM classifier. To evaluate the prediction performance of our model, several SVM-based prediction models are utilized for comparison on a study area of the Wanzhou district in the Three Gorges Reservoir. Experimental results, based on three objective quantitative measures and visual qualitative evaluation, indicate that our model can achieve better prediction accuracies and is more effective for landslide susceptibility mapping. For instance, our model can achieve an overall prediction accuracy of 91.10%, which is 7.8%-19.1% higher than the traditional SVM-based models. In addition, the obtained landslide susceptibility map by our model can demonstrate an intensive correlation between the classified very high-susceptibility zone and the previously investigated landslides.

  7. Mapping Forest Fire Susceptibility in Temperate Mountain Areas with Expert Knowledge. A Case Study from Iezer Mountains, Romanian Carpathians

    Science.gov (United States)

    Mihai, Bogdan; Savulescu, Ionut

    2014-05-01

    Forest fires in Romanian Carpathians became a frequent phenomenon during the last decade, although local climate and other environmental features did not create typical conditions. From 2004, forest fires affect in Romania more than 100 hectares/year of different forest types (deciduous and coniferous). Their magnitude and frequency are not known, since a historical forest fire inventory does not exist (only press papers and local witness for some selected events). Forest fires features the summer dry periods but there are dry autumns and early winter periods with events of different magnitudes. The application we propose is based on an empirical modeling of forest fire susceptibility in a typical mountain area from the Southern Carpathians, the Iezer Mountains (2462 m). The study area features almost all the altitudinal vegetation zones of the European temperate mountains, from the beech zone, to the coniferous zone, the subalpine and the alpine zones (Mihai et al., 2007). The analysis combines GIS and remote sensing models (Chuvieco et al., 2012), starting from the ideas that forest fires are featured by the ignition zones and then by the fire propagation zones. The first data layer (ignition zones) is the result of the crossing between the ignition factors: lightning - points of multitemporal occurence and anthropogenic activities (grazing, tourism and traffic) and the ignition zones (forest fuel zonation - forest stands, soil cover and topoclimatic factor zonation). This data is modelled from different sources: the MODIS imagery fire product (Hantson et al., 2012), detailed topographic maps, multitemporal orthophotos at 0.5 m resolution, Landsat multispectral imagery, forestry cadastre maps, detailed soil maps, meteorological data (the WorldClim digital database) as well as the field survey (mapping using GPS and local observation). The second data layer (fire propagation zones) is the result of the crossing between the forest fuel zonation, obtained with the

  8. Area-specific migration and recruitment of new neurons in the adult songbird brain

    DEFF Research Database (Denmark)

    Vellema, Michiel; Van der Linden, Annemie; Gahr, Manfred

    2010-01-01

    sensitive to plastic changes, such as nucleus higher vocal center (HVC) and area X, recruited similar numbers of new neurons as their surrounding brain tissues, employing no specific directional mechanisms. The distribution pattern in and around HVC could best be described by a random displacement model......Neuron recruitment has been implicated in morphological and functional plasticity in the adult brain. Whereas mammals restrict neuron recruitment specifically to two regions of known plasticity, the hippocampus and olfactory bulb, newborn neurons are found throughout the forebrain of adult...... songbirds. In order to study the area-specificity of the widespread proliferation and recruitment in the songbird brain, six adult male canaries received repetitive intraperitoneal injections of the mitotic marker BrdU (5-bromo-2-deoxyuridine) and were sacrificed after 24 hours to study proliferation...

  9. Optimal staining methods for delineation of cortical areas and neuron counts in human brains.

    Science.gov (United States)

    Uylings, H B; Zilles, K; Rajkowska, G

    1999-04-01

    For cytoarchitectonic delineation of cortical areas in human brain, the Gallyas staining for somata with its sharp contrast between cell bodies and neuropil is preferable to the classical Nissl staining, the more so when an image analysis system is used. This Gallyas staining, however, does not appear to be appropriate for counting neuron numbers in pertinent brain areas, due to the lack of distinct cytological features between small neurons and glial cells. For cell counting Nissl is preferable. In an optimal design for cell counting at least both the Gallyas and the Nissl staining must be applied, the former staining for cytoarchitectural delineaton of cortical areas and the latter for counting the number of neurons in the pertinent cortical areas. Copyright 1999 Academic Press.

  10. Inter-species activity correlations reveal functional correspondences between monkey and human brain areas

    Science.gov (United States)

    Mantini, Dante; Hasson, Uri; Betti, Viviana; Perrucci, Mauro G.; Romani, Gian Luca; Corbetta, Maurizio; Orban, Guy A.; Vanduffel, Wim

    2012-01-01

    Evolution-driven functional changes in the primate brain are typically assessed by aligning monkey and human activation maps using cortical surface expansion models. These models use putative homologous areas as registration landmarks, assuming they are functionally correspondent. In cases where functional changes have occurred in an area, this assumption prohibits to reveal whether other areas may have assumed lost functions. Here we describe a method to examine functional correspondences across species. Without making spatial assumptions, we assess similarities in sensory-driven functional magnetic resonance imaging responses between monkey (Macaca mulatta) and human brain areas by means of temporal correlation. Using natural vision data, we reveal regions for which functional processing has shifted to topologically divergent locations during evolution. We conclude that substantial evolution-driven functional reorganizations have occurred, not always consistent with cortical expansion processes. This novel framework for evaluating changes in functional architecture is crucial to building more accurate evolutionary models. PMID:22306809

  11. Nonspatial intermodal selective attention is mediated by sensory brain areas: Evidence from event-related potential.

    NARCIS (Netherlands)

    Talsma, D.; Kok, A.

    2001-01-01

    Focuses on the question of whether inter-and intramodal forms of attention are reflected in activation of the same or different brain areas. ERPs were recorded while Ss (aged 18-41 yrs) were presented a random sequence of visual and auditory stimuli. They were instructed to attend to nonspatial

  12. Nonspatial intermodal selective attention is mediated by sensory brain areas: Evidence from event-related potentials

    NARCIS (Netherlands)

    Talsma, D.; Kok, Albert

    2001-01-01

    The present study focuses on the question of whether inter- and intramodal forms of attention are reflected in activation of the same or different brain areas. ERPs were recorded while subjects were presented a random sequence of visual and auditory stimuli. They were instructed to attend to

  13. Short- and long-term modulation of synaptic inputs to brain reward areas by nicotine

    NARCIS (Netherlands)

    Fagen, Z.M.; Mansvelder, H.D.; Keath, R.; McGehee, D.S.

    2003-01-01

    Dopamine signaling in brain reward areas is a key element in the development of drug abuse and dependence. Recent anatomical and electrophysiological research has begun to elucidate both complexity and specificity In synaptic connections between ventral tegmental neurons and their inputs.

  14. The Safe Area in the Parieto-Occipital Lobe in the Human Brain: Diffusion Tensor Tractography.

    Science.gov (United States)

    Jang, Sung Ho; Kim, Seong Ho; Kwon, Hyeok Gyu

    2015-06-01

    A recent study reported on the relatively safe area in the frontal lobe for performance of neurological interventions; however, no study on the posterior safe area has been reported. In this study, using diffusion tensor tractography, we attempted to identify the safe area in the parieto-occipital lobe in healthy subjects. A total of 47 healthy subjects were recruited for this study. Eleven neural tracts were reconstructed in and around the parieto-occipital area of the brain using diffusion tensor tractography. The safe area, which is free from any trajectory of 10 neural tracts, was measured anteriorly and medially from the line of the most posterior and lateral margin of the brain at 5 axial levels (from the cerebral cortex to the corona radiata). The anterior boundaries of the safe area in the upper cerebral cortex, lower cerebral cortex, centrum semiovale, upper corona radiata, and lower corona radiata levels were located at 31.0, 32.6, 32.7, 35.1, and 35.2 mm anteriorly from the line of the most posterior margin of the brain, respectively, and the medial boundaries were located at an average of 34.7, 38.1, 39.2, 36.1, and 33.6 mm medially from the line of the most lateral margin of the brain, respectively. According to our findings, the safe area was located in the posterolateral portion of the parieto-occipital lobe in the shape of a triangle. However, we found no safe area in the deep white matter around the lateral ventricle. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. A split microdrive for simultaneous multi-electrode recordings from two brain areas in awake small animals.

    NARCIS (Netherlands)

    Lansink, C.S.; Bakker, M.; Buster, W.; Lankelma, J.; van der Blom, R.; Westdorp, R.; Joosten, R.N.J.M.A.; Mc.Naughton, B.L.; Pennartz, C.M.A.

    2007-01-01

    Complex cognitive operations such as memory formation and decision-making are thought to be mediated not by single, isolated brain structures but by multiple, connected brain areas. To facilitate studies on the neural communication between connected brain structures, we developed a multi-electrode

  16. Landslide susceptibility assessment by using a neuro-fuzzy model: a case study in the Rupestrian heritage rich area of Matera

    Science.gov (United States)

    Sdao, F.; Lioi, D. S.; Pascale, S.; Caniani, D.; Mancini, I. M.

    2013-02-01

    The complete assessment of landslide susceptibility needs uniformly distributed detailed information on the territory. This information, which is related to the temporal occurrence of landslide phenomena and their causes, is often fragmented and heterogeneous. The present study evaluates the landslide susceptibility map of the Natural Archaeological Park of Matera (Southern Italy) (Sassi and area Rupestrian Churches sites). The assessment of the degree of "spatial hazard" or "susceptibility" was carried out by the spatial prediction regardless of the return time of the events. The evaluation model for the susceptibility presented in this paper is very focused on the use of innovative techniques of artificial intelligence such as Neural Network, Fuzzy Logic and Neuro-fuzzy Network. The method described in this paper is a novel technique based on a neuro-fuzzy system. It is able to train data like neural network and it is able to shape and control uncertain and complex systems like a fuzzy system. This methodology allows us to derive susceptibility maps of the study area. These data are obtained from thematic maps representing the parameters responsible for the instability of the slopes. The parameters used in the analysis are: plan curvature, elevation (DEM), angle and aspect of the slope, lithology, fracture density, kinematic hazard index of planar and wedge sliding and toppling. Moreover, this method is characterized by the network training which uses a training matrix, consisting of input and output training data, which determine the landslide susceptibility. The neuro-fuzzy method was integrated to a sensitivity analysis in order to overcome the uncertainty linked to the used membership functions. The method was compared to the landslide inventory map and was validated by applying three methods: a ROC (Receiver Operating Characteristic) analysis, a confusion matrix and a SCAI method. The developed neuro-fuzzy method showed a good performance in the

  17. Low-grade astrocytoma: surgical outcomes in eloquent versus non-eloquent brain areas

    Directory of Open Access Journals (Sweden)

    André de Macedo Bianco

    2013-01-01

    Full Text Available A retrospective study of 81 patients with low-grade astrocytoma (LGA comparing the efficacy of aggressive versus less aggressive surgery in eloquent and non-eloquent brain areas was conducted. Extent of surgical resection was analyzed to assess overall survival (OS and progression- free survival (PFS. Degree of tumor resection was classified as gross total resection (GTR, subtotal resection (STR or biopsy. GTR, STR and biopsy in patients with tumors in non-eloquent areas were performed in 31, 48 and 21% subjects, whereas in patients with tumors in eloquent areas resections were 22.5, 35 and 42.5%. Overall survival was 4.7 and 1.9 years in patients with tumors in non-eloquent brain areas submitted to GTR/STR and biopsy (p=0.013, whereas overall survival among patients with tumors in eloquent area was 4.5 and 2.1 years (p=0.33. Improved outcome for adult patients with LGA is predicted by more aggressive surgery in both eloquent and non-eloquent brain areas.

  18. Eloquent area in the gamma knife treatment of arteriovenous malformations of the brain

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Tatsuya; Kida, Yoshihisa; Tanaka, Takayuki; Yoshida, Kazuo; Mori, Yoshimasa; Ohsuga, Koji; Hasegawa, Toshinori; Kondo, Toshiki [Komaki City Hospital, Aichi (Japan)

    1999-06-01

    It has been long since cerebral arteriovenous malformation (AVM) could be cured by gamma radiosurgery. In this study, it has been found that the complete obliteration of AVM by radiosurgery is depended on the factors such as the size of the nidus, the marginal dose, the location and the age of patients. It is also true that higher the marginal dose, higher the obliteration rate and also higher the risk of radiation injury. Therefore the marginal dose has to be limited by the radiosensitivity (tolerance) of surrounding brain, which means the obliteration rate is largely depended on the location of AVM. The definition of the eloquent area of AVM by microsurgery is based upon the anatomical and functional importance of the brain. However, the eloquency in radiosurgery is different in that it depends upon radiosensitivity of the surrounding brain around AVM. From this definition, the most eloquent area by radiosurgery is brain around the optic pathway, followed by cochlear nerve, other cranial nerves, brain stem and basal ganglia-thalamus. (author)

  19. Not single brain areas but a network is involved in language: Applications in presurgical planning.

    Science.gov (United States)

    Alemi, Razieh; Batouli, Seyed Amir Hossein; Behzad, Ebrahim; Ebrahimpoor, Mitra; Oghabian, Mohammad Ali

    2018-02-01

    Language is an important human function, and is a determinant of the quality of life. In conditions such as brain lesions, disruption of the language function may occur, and lesion resection is a solution for that. Presurgical planning to determine the language-related brain areas would enhance the chances of language preservation after the operation; however, availability of a normative language template is essential. In this study, using data from 60 young individuals who were meticulously checked for mental and physical health, and using fMRI and robust imaging and data analysis methods, functional brain maps for the language production, perception and semantic were produced. The obtained templates showed that the language function should be considered as the product of the collaboration of a network of brain regions, instead of considering only few brain areas to be involved in that. This study has important clinical applications, and extends our knowledge on the neuroanatomy of the language function. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Automatic extraction analysis of the anatomical functional area for normal brain 18F-FDG PET imaging

    International Nuclear Information System (INIS)

    Guo Wanhua; Jiang Xufeng; Zhang Liying; Lu Zhongwei; Li Peiyong; Zhu Chengmo; Zhang Jiange; Pan Jiapu

    2003-01-01

    Using self-designed automatic extraction software of brain functional area, the grey scale distribution of 18 F-FDG imaging and the relationship between the 18 F-FDG accumulation of brain anatomic function area and the 18 F-FDG injected dose, the level of glucose, the age, etc., were studied. According to the Talairach coordinate system, after rotation, drift and plastic deformation, the 18 F-FDG PET imaging was registered into the Talairach coordinate atlas, and then the average gray value scale ratios between individual brain anatomic functional area and whole brain area was calculated. Further more the statistics of the relationship between the 18 F-FDG accumulation of every brain anatomic function area and the 18 F-FDG injected dose, the level of glucose and the age were tested by using multiple stepwise regression model. After images' registration, smoothing and extraction, main cerebral cortex of the 18 F-FDG PET brain imaging can be successfully localized and extracted, such as frontal lobe, parietal lobe, occipital lobe, temporal lobe, cerebellum, brain ventricle, thalamus and hippocampus. The average ratios to the inner reference of every brain anatomic functional area were 1.01 ± 0.15. By multiple stepwise regression with the exception of thalamus and hippocampus, the grey scale of all the brain functional area was negatively correlated to the ages, but with no correlation to blood sugar and dose in all areas. To the 18 F-FDG PET imaging, the brain functional area extraction program could automatically delineate most of the cerebral cortical area, and also successfully reflect the brain blood and metabolic study, but extraction of the more detailed area needs further investigation

  1. Association of catalase gene polymorphisms with catalase activity and susceptibility to systemic lupus erythematosus in the Suez Canal area, Egypt.

    Science.gov (United States)

    Ghaly, M S; Ghattas, M H; Labib, S M

    2012-10-01

    The present study evaluated the relationship of genetic variants in both promoter (-262 C/T) and in exonic (389 C/T) regions of the catalase (CAT) gene to CAT activity and risk of systemic lupus erythematosus (SLE) in Suez Canal-area patients. CAT gene polymorphisms were assessed by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). CAT activity was measured by using a spectrophotometer. We compared the frequencies of CAT 389 C/T and -262 C/T polymorphic variants between SLE patients (n = 103) and healthy controls (n = 103). CAT 389 C/T is associated with SLE susceptibility, with the T allele being significantly more frequent among SLE patients than healthy controls. There was no association, however, between CAT activity and genotypes of 389 C/T. We did not observe significant differences in the prevalence of CAT -262 C/T polymorphic variants in SLE patients and controls, however, we found that patients with the CAT -262 CT and TT genotypes had low CAT activity, and these genotypes showed a significant association with thrombocytopaenia, leukopaenia and the presence of anti-snRNP in SLE patients. In conclusion, the present study supports the notion of in vivo oxidative stress in SLE as indicated by the decrease in CAT activity. The allelic variations in the CAT gene -262 are more likely to affect the expression or the function of the enzyme. Since CAT may be pathogenetically linked to SLE, and owing to its free-radical origin, it appears reasonable to target lipid peroxidation by dietary and/or pharmacological antioxidants.

  2. [Antibiotic susceptibility of Staphylococcus aureus and Streptococcus pneumoniae in healthy carrier individuals in primary care in Barcelona area].

    Science.gov (United States)

    Llor, Carles; Boada, Albert; Pons-Vigués, Mariona; Grenzner, Elisabet; Juvé, Rosa; Almeda, Jesús

    2018-01-01

    The information available on antibiotic resistance patterns are generally based on specimens from hospitalised individuals. This study was aimed at evaluating the antibiotic resistance rate of nasal carriage strains of Staphylococcus aureus and Streptococcus pneumoniae in healthy individuals, in accordance with age and gender, attended in Primary Care Centres (PCC). Cross-sectional study. Seven PCC in the Barcelona area. Healthy nasal carriers aged 4years or more who did not present with any sign of infectious disease, and had not taken any antibiotic or had been hospitalised in the previous 3months. A total of 3,969 nasal swabs valid for identification were collected between 2010 and 2011 and were sent to one central microbiological laboratory for isolation of both pathogens. Resistance to common antibiotics was determined on the basis of the current European Committee on Antimicrobial Susceptibility Testing guidelines on cut-off points. The prevalence of methicillin-resistant S.aureus was 1.3% (95%CI: 0.5-2.1%), with resistance rates of 87.1% to phenoxymethylpenicillin and 11.6% to azithromycin, with no significant differences with age and gender. A total of 2.4% (95CI%: 0.1-4.7%) of the pneumococcal strains were highly resistant to both phenoxymethylpenicillin and macrolides, whereas the highest resistance rates were to cefaclor (53.3%), followed by tetracycline (20%) and cefuroxime (12.1%). These pathogens have lower resistance rates in the community than in the hospital setting. Primary Care physicians must be more aware of the current antimicrobial resistance, in order to ensure prudent use of antibiotics. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

  3. AGING AND LIFE-STAGE SUSCEPTIBILITY: TOLUENE EFFECTS ON BRAIN OXIDATIVE STRESS PARAMETERS IN BROWN NORWAY RATS.

    Science.gov (United States)

    The influence of aging on susceptibility to environmental contaminants is poorly understood. The objectives of this study were to test whether oxidative stress (OS) is a potential toxicity pathway following toluene exposure and to determine if these effects are age-dependent. We ...

  4. Brain pattern of histone H3 phosphorylation after acute amphetamine administration: its relationship to brain c-fos induction is strongly dependent on the particular brain area.

    Science.gov (United States)

    Rotllant, David; Armario, Antonio

    2012-02-01

    Recent evidence strongly suggests a critical role of chromatin remodelling in the acute and chronic effects of addictive drugs. We reasoned that Immunohistochemical detection of certain histone modifications may be a more specific tool than induction of immediate early genes (i.e. c-fos) to detect brain areas and neurons that are critical for the action of addictive drugs. Thus, in the present work we studied in adult male rats the effects of a high dose of amphetamine on brain pattern of histone H3 phosphorylation in serine 10 (pH3S(10)) and c-fos expression. We firstly observed that amphetamine-induced an increase in the number of pH3S(10) positive neurons in a restricted number of brain areas, with maximum levels at 30 min after the drug administration that declined at 90 min in most areas. In a second experiment we studied colocalization of pH3S(10) immunoreactivity (pH3S(10)-IR) and c-fos expression. Amphetamine increased c-fos expression in medial prefrontal cortex (mPFC), dorsal striatum, nucleus accumbens (Acb), major Island of Calleja (ICjM), central amygdala (CeA), bed nucleus of stria terminalis lateral dorsal (BSTld) and paraventricular nucleus of the hypothalamus (PVN). Whereas no evidence for increase in pH3S(10) positive neurons was found in the mPFC and the PVN, in the striatum and the Acb basically all pH3S(10) positive neurons showed colocalization with c-fos. In ICjM, CeA and BSTld a notable degree of colocalization was found, but an important number of neurons expressing c-fos were negative for pH3S(10). The present results give support to the hypothesis that amphetamine-induced pH3S(10)-IR showed a more restricted pattern than brain c-fos induction, being this difference strongly dependent on the particular brain area studied. It is likely that those nuclei and neurons showing pH3S(10)-IR are more specifically associated to important effects of the drug, including neural plasticity. This article is part of a Special Issue entitled 'Post

  5. On the calculation of brain area shifts due to cerebral tumors

    International Nuclear Information System (INIS)

    Labudde, D.; Hartmann, S.; Synowitz, M.

    2002-01-01

    A precise knowledge of the localization of an intracerebral mass is a basic requirement for the planning of neurosurgical operations. Stereotactic atlases offer the possibility to adapt pre-operative imaging data onto normal anatomical conditions in the CNS. These atlases, however, reflect the standard variants of the CNS and do not allow to draw conclusions on local and secondary changes of the anatomy caused by the presence of pathological processes. The physical model proposed in this paper provides an estimate of the displacement of brain areas by an intracerebral mass. The modeling of brain parenchyma deformation is based on the mechanics of deformed media. The implementation of the model is successful in the group of primary brain tumors and meningiomas, and uses empirically-obtained data of a prospectively-selected patient population. The aim of the proposed model is, as further step, the integration and adaptation in apposite software solutions for the stereotactic orientation in the CNS. (orig.) [de

  6. Trajectories of cortical surface area and cortical volume maturation in normal brain development

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    Simon Ducharme

    2015-12-01

    Full Text Available This is a report of developmental trajectories of cortical surface area and cortical volume in the NIH MRI Study of Normal Brain Development. The quality-controlled sample included 384 individual typically-developing subjects with repeated scanning (1–3 per subject, total scans n=753 from 4.9 to 22.3 years of age. The best-fit model (cubic, quadratic, or first-order linear was identified at each vertex using mixed-effects models, with statistical correction for multiple comparisons using random field theory. Analyses were performed with and without controlling for total brain volume. These data are provided for reference and comparison with other databases. Further discussion and interpretation on cortical developmental trajectories can be found in the associated Ducharme et al.׳s article “Trajectories of cortical thickness maturation in normal brain development – the importance of quality control procedures” (Ducharme et al., 2015 [1].

  7. The Corpus Callosum Area and Brain Volume in Alzheimer's Disease, Mild Cognitive Impairment and Healthy Controls

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    Choi, Hee Seok; Kim, Kwang Ki; Yoon, Yup Yoon [Dongguk University Medical Center, Goyang (Korea, Republic of); Seo, Hyung Suk [Korea University Ansan Hospital, Ansan (Korea, Republic of)

    2009-07-15

    To compare the corpus callosum (CC) area and brain volume among individuals with Alzheimer's disease (AD), mild cognitive impairment (MCI) and healthy controls (HC). To evaluate the relationship of CC area and brain volume in 111 subjects (M:F = 48:63; mean age, 56.9 years) without memory disturbance and 28 subjects (11:17; 66.7years) with memory disturbance. The 11 AD (3:8; 75.7 years), 17 MCI (8:9; 60.9 years) and 28 selected HC (11:17; 66.4 years) patients were investigated for comparison of their CC area and brain volume. A good positive linear correlation was found between CC area and brain volume in subjects without and with memory disturbance (r = 0.64 and 0.66, respectively, p < 0.01). The CC area and brain volume in AD patients (498.7 +- 72 mm{sup 2}, 715.4 +- 107 cm3) were significantly smaller than in MCI patients (595.9 +- 108, 844.1 +- 85) and the HCs (563.2 +- 75, 818.9 +- 109) (p < 0.05). The CC area and brain volume were not significantly different between MCI patients and the HCs. The CC area was significantly correlated with brain volume. Both CC area and brain volume were significantly smaller in the AD patients

  8. Motor areas of the frontal cortex in patients with motor eloquent brain lesions.

    Science.gov (United States)

    Bulubas, Lucia; Sabih, Jamil; Wohlschlaeger, Afra; Sollmann, Nico; Hauck, Theresa; Ille, Sebastian; Ringel, Florian; Meyer, Bernhard; Krieg, Sandro M

    2016-12-01

    OBJECTIVE Because of its huge clinical potential, the importance of premotor areas for motor function itself and plastic reshaping due to tumors or ischemic brain lesions has received increased attention. Thus, in this study the authors used navigated transcranial magnetic stimulation (nTMS) to investigate whether tumorous brain lesions induce a change in motor cortex localization in the human brain. METHODS Between 2010 and 2013, nTMS motor mapping was performed in a prospective cohort of 100 patients with brain tumors in or adjacent to the rolandic cortex. Spatial data analysis was performed by normalization of the individual motor maps and creation of overlays according to tumor location. Analysis of motor evoked potential (MEP) latencies was performed regarding mean overall latencies and potentially polysynaptic latencies, defined as latencies longer than 1 SD above the mean value. Hemispheric dominance, lesion location, and motor-function deficits were also considered. RESULTS Graphical analysis showed that motor areas were not restricted to the precentral gyrus. Instead, they spread widely in the anterior-posterior direction. An analysis of MEP latency showed that mean MEP latencies were shortest in the precentral gyrus and longest in the superior and middle frontal gyri. The percentage of latencies longer than 1 SD differed widely across gyri. The dominant hemisphere showed a greater number of longer latencies than the nondominant hemisphere (p < 0.0001). Moreover, tumor location-dependent changes in distribution of polysynaptic latencies were observed (p = 0.0002). Motor-function deficit did not show any statistically significant effect. CONCLUSIONS The distribution of primary and polysynaptic motor areas changes in patients with brain tumors and highly depends on tumor location. Thus, these data should be considered for resection planning.

  9. Testosterone depletion increases the susceptibility of brain tissue to oxidative damage in a restraint stress mouse model.

    Science.gov (United States)

    Son, Seung-Wan; Lee, Jin-Seok; Kim, Hyeong-Geug; Kim, Dong-Woon; Ahn, Yo-Chan; Son, Chang-Gue

    2016-01-01

    Among sex hormones, estrogen is particularly well known to act as neuroprotective agent. Unlike estrogen, testosterone has not been well investigated in regard to its effects on the brain, especially under psychological stress. To investigate the role of testosterone in oxidative brain injuries under psychological stress, we adapted an orchiectomy and restraint stress model. BALB/c mice were subjected to either an orchiectomy or sham operation. After allowing 15 days for recovery, mice were re-divided into four groups according to exposure of restraint stress: sham, sham plus stress, orchiectomy, and orchiectomy plus stress. Serum testosterone was undetectable in orchiectomized groups and restraint-induced stress significantly reduced testosterone levels in sham plus stress group. The serum levels of corticosterone and adrenaline were notably elevated by restraint stress, and these elevated hormones were markedly augmented by orchiectomy. Two oxidative stressors and biomarkers for lipid and protein peroxidation were significantly increased in the cerebral cortex and hippocampus by restraint stress, while the reverse pattern was observed in antioxidant enzymes. These results were supported by histopathological findings, with 4-hydroxynonenal staining for oxidative injury and Fluoro-Jade B staining showing the degenerating neurons. The aforementioned patterns of oxidative injury were accelerated by orchiectomy. These findings strongly suggest the conclusion that testosterone exerts a protective effect against oxidative brain damage, especially under stressed conditions. Unlike estrogen, the effects of testosterone on the brain have not been thoroughly investigated. In order to investigate the role of testosterone in oxidative brain injuries under psychological stress, we adapted an orchiectomy and restraint stress model. Orchiectomy markedly augmented the restraint stress-induced elevation of serum corticosterone and adrenaline levels as well as oxidative alterations

  10. Molecular mechanisms of aluminium ions neurotoxicity in brain cells of fish from various pelagic areas

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    E. V. Sukharenko

    2017-07-01

    Full Text Available Neurotoxic effects of aluminum chloride in higher than usual environment concentration (10 mg/L were studied in brains of fishes from various pelagic areas, especially in sunfish (Lepomis macrochirus Rafinesque, 1819, roach (Rutilus rutilus Linnaeus, 1758, crucian carp (Carasius carasius Linnaeus, 1758, goby (Neogobius fluviatilis Pallas, 1811. The intensity of oxidative stress and the content of both cytoskeleton protein GFAP and cytosol Ca-binding protein S100β were determined. The differences in oxidative stress data were observed in the liver and brain of fish during 45 days of treatment with aluminum chloride. The data indicated that in the modeling of aluminum intoxication in mature adult fishes the level of oxidative stress was noticeably higher in the brain than in the liver. This index was lower by1.5–2.0 times on average in the liver cells than in the brain. The obtained data evidently demonstrate high sensitivity to aluminum ions in neural tissue cells of fish from various pelagic areas. Chronic intoxication with aluminum ions induced intense astrogliosis in the fish brain. Astrogliosis was determined as result of overexpression of both cytoskeleton and cytosole markers of astrocytes – GFAP and protein S100β (on 75–112% and 67–105% accordingly. Moreover, it was shown that the neurotixic effect of aluminum ions is closely related to metabolism of astroglial intermediate filaments. The results of western blotting showed a considerable increase in the content of the lysis protein products of GFAP with a range of molecular weight from 40–49 kDa. A similar metabolic disturbance was determined for the upregulation protein S100β expression and particularly in the increase in the content of polypeptide fragments of this protein with molecular weight 24–37 kDa. Thus, the obtained results allow one to presume that aluminum ions activate in the fish brain intracellular proteases which have a capacity to destroy the proteins of

  11. Brain stimulation used as biofeedback in neuronal activation of the temporal lobe area in autistic children

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    Vernon Furtado da Silva

    2016-08-01

    Full Text Available ABSTRACT This study focused upon the functional capacity of mirror neurons in autistic children. 30 individuals, 10 carriers of the autistic syndrome (GCA, 10 with intellectual impairments (GDI, and 10 non-autistics (GCN had registered eletroencephalogram from the brain area theoretically related to mirror neurons. Data collection procedure occurred prior to brain stimulation and after the stimulation session. During the second session, participants had to alternately process figures evoking neutral, happy, and/or sorrowful feelings. Results proved that, for all groups, the stimulation process in fact produced additional activation in the neural area under study. The level of activation was related to the format of emotional stimuli and the likelihood of boosting such stimuli. Since the increase of activation occurred in a model similar to the one observed for the control group, we may suggest that the difficulty people with autism have at expressing emotions is not due to nonexistence of mirror neurons.

  12. Brain stimulation used as biofeedback in neuronal activation of the temporal lobe area in autistic children.

    Science.gov (United States)

    Silva, Vernon Furtado da; Calomeni, Mauricio Rocha; Nunes, Rodolfo Alkmim Moreira; Pimentel, Carlos Elias; Martins, Gabriela Paes; Oliveira, Patrícia da Cruz Araruna; Silva, Patrícia Bagno; Silva, Alair Pedro Ribeiro de Souza E

    2016-08-01

    This study focused upon the functional capacity of mirror neurons in autistic children. 30 individuals, 10 carriers of the autistic syndrome (GCA), 10 with intellectual impairments (GDI), and 10 non-autistics (GCN) had registered eletroencephalogram from the brain area theoretically related to mirror neurons. Data collection procedure occurred prior to brain stimulation and after the stimulation session. During the second session, participants had to alternately process figures evoking neutral, happy, and/or sorrowful feelings. Results proved that, for all groups, the stimulation process in fact produced additional activation in the neural area under study. The level of activation was related to the format of emotional stimuli and the likelihood of boosting such stimuli. Since the increase of activation occurred in a model similar to the one observed for the control group, we may suggest that the difficulty people with autism have at expressing emotions is not due to nonexistence of mirror neurons.

  13. Uni- and Multisensory Brain Areas are Synchronised across Spectators When Watching Unedited Dance Recordings

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    Corinne Jola

    2013-06-01

    Full Text Available The superior temporal sulcus (STS and gyrus (STG are commonly identified to be functionally relevant for multisensory integration of audiovisual (AV stimuli. However, most neuroimaging studies on AV integration used stimuli of short duration in explicit evaluative tasks. Importantly though, many of our AV experiences are of a long duration and ambiguous. It is unclear if the enhanced activity in audio, visual, and AV brain areas would also be synchronised over time across subjects when they are exposed to such multisensory stimuli. We used intersubject correlation to investigate which brain areas are synchronised across novices for uni- and multisensory versions of a 6-min 26-s recording of an unfamiliar, unedited Indian dance recording (Bharatanatyam. In Bharatanatyam, music and dance are choreographed together in a highly intermodal-dependent manner. Activity in the middle and posterior STG was significantly correlated between subjects and showed also significant enhancement for AV integration when the functional magnetic resonance signals were contrasted against each other using a general linear model conjunction analysis. These results extend previous studies by showing an intermediate step of synchronisation for novices: while there was a consensus across subjects' brain activity in areas relevant for unisensory processing and AV integration of related audio and visual stimuli, we found no evidence for synchronisation of higher level cognitive processes, suggesting these were idiosyncratic.

  14. Tropical Forest Fire Susceptibility Mapping at the Cat Ba National Park Area, Hai Phong City, Vietnam, Using GIS-Based Kernel Logistic Regression

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    Dieu Tien Bui

    2016-04-01

    Full Text Available The Cat Ba National Park area (Vietnam with its tropical forest is recognized as being part of the world biodiversity conservation by the United Nations Educational, Scientific and Cultural Organization (UNESCO and is a well-known destination for tourists, with around 500,000 travelers per year. This area has been the site for many research projects; however, no project has been carried out for forest fire susceptibility assessment. Thus, protection of the forest including fire prevention is one of the main concerns of the local authorities. This work aims to produce a tropical forest fire susceptibility map for the Cat Ba National Park area, which may be helpful for the local authorities in forest fire protection management. To obtain this purpose, first, historical forest fires and related factors were collected from various sources to construct a GIS database. Then, a forest fire susceptibility model was developed using Kernel logistic regression. The quality of the model was assessed using the Receiver Operating Characteristic (ROC curve, area under the ROC curve (AUC, and five statistical evaluation measures. The usability of the resulting model is further compared with a benchmark model, the support vector machine (SVM. The results show that the Kernel logistic regression model has a high level of performance in both the training and validation dataset, with a prediction capability of 92.2%. Since the Kernel logistic regression model outperforms the benchmark model, we conclude that the proposed model is a promising alternative tool that should also be considered for forest fire susceptibility mapping in other areas. The results of this study are useful for the local authorities in forest planning and management.

  15. Activated and deactivated functional brain areas in the Deqi state: A functional MRI study.

    Science.gov (United States)

    Huang, Yong; Zeng, Tongjun; Zhang, Guifeng; Li, Ganlong; Lu, Na; Lai, Xinsheng; Lu, Yangjia; Chen, Jiarong

    2012-10-25

    We compared the activities of functional regions of the brain in the Deqi versus non-Deqi state, as reported by physicians and subjects during acupuncture. Twelve healthy volunteers received sham and true needling at the Waiguan (TE5) acupoint. Real-time cerebral functional MRI showed that compared with non-sensation after sham needling, true needling activated Brodmann areas 3, 6, 8, 9, 10, 11, 13, 20, 21, 37, 39, 40, 43, and 47, the head of the caudate nucleus, the parahippocampal gyrus, thalamus and red nucleus. True needling also deactivated Brodmann areas 1, 2, 3, 4, 5, 6, 7, 9, 10, 18, 24, 31, 40 and 46.

  16. The Land’s Susceptibility, Due to Atmospheric Precipitations, Within the Catchment Area of Câlnău

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    (Oprea Constantin Dana Maria

    2014-05-01

    Full Text Available The climatic factors, generally, and the precipitation amounts recorded, especially, constitute some of the factors which condition the development and intensity of actual geomorphologic processes. One of the most employed climatic parameters for determining the land’s susceptibility to atmospheric precipitations, with real and concrete applications into the dynamic geomorphology, is the Angot factor.

  17. Altered intraoperative cerebrovascular reactivity in brain areas of high-grade glioma recurrence.

    Science.gov (United States)

    Fierstra, Jorn; van Niftrik, Bas; Piccirelli, Marco; Burkhardt, Jan Karl; Pangalu, Athina; Kocian, Roman; Valavanis, Antonios; Weller, Michael; Regli, Luca; Bozinov, Oliver

    2016-07-01

    Current MRI sequences are limited in identifying brain areas at risk for high grade glioma recurrence. We employed intraoperative 3-Tesla functional MRI to assess cerebrovascular reactivity (CVR) after high-grade glioma resection and analyzed regional CVR responses in areas of tumor recurrence on clinical follow-up imaging. Five subjects with high-grade glioma that underwent an intraoperative Blood Oxygen-Level Dependent (BOLD) MRI CVR examination and had a clinical follow-up of at least 18months were selected from a prospective database. For this study, location of tumor recurrence was spatially matched to the intraoperative imaging to assess CVR response in that particular area. CVR is defined as the percent BOLD signal change during repeated cycles of apnea. Of the 5 subjects (mean age 44, 2 females), 4 were diagnosed with a WHO grade III and 1 subject with a WHO grade IV glioma. Three subjects exhibited a tumor recurrence on clinical follow-up MRI (mean: 15months). BOLD CVR measured in the spatially matched area of tumor recurrence was on average 94% increased (range-32% to 183%) as compared to contralateral hemisphere CVR response, 1.50±0.81 versus 1.03±0.46 respectively (p=0.31). For this first analysis in a small cohort, we found altered intraoperative CVR in brain areas exhibiting high grade glioma recurrence on clinical follow-up imaging. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. [Surgical treatment of eloquent brain area tumors using neurophysiological mapping of the speech and motor areas and conduction tracts].

    Science.gov (United States)

    Zuev, A A; Korotchenko, E N; Ivanova, D S; Pedyash, N V; Teplykh, B A

    To evaluate the efficacy of intraoperative neurophysiological mapping in removing eloquent brain area tumors (EBATs). Sixty five EBAT patients underwent surgical treatment using intraoperative neurophysiological mapping at the Pirogov National Medical and Surgical Center in the period from 2014 to 2015. On primary neurological examination, 46 (71%) patients were detected with motor deficits of varying severity. Speech disorders were diagnosed in 17 (26%) patients. Sixteen patients with concomitant or isolated lesions of the speech centers underwent awake surgery using the asleep-awake-asleep protocol. Standard neurophysiological monitoring included transcranial stimulation as well as motor and, if necessary, speech mapping. The motor and speech areas were mapped with allowance for the preoperative planning data (obtained with a navigation station) synchronized with functional MRI. In this case, a broader representation of the motor and speech centers was revealed in 12 (19%) patients. During speech mapping, no speech disorders were detected in 7 patients; in 9 patients, stimulation of the cerebral cortex in the intended surgical area induced motor (3 patients), sensory (4), and amnesic (2) aphasia. In the total group, we identified 11 patients in whom the tumor was located near the internal capsule. Upon mapping of the conduction tracts in the internal capsule area, the stimulus strength during tumor resection was gradually decreased from 10 mA to 5 mA. Tumor resection was stopped when responses retained at a stimulus strength of 5 mA, which, when compared to the navigation data, corresponded to a distance of about 5 mm to the internal capsule. Completeness of tumor resection was evaluated (contrast-enhanced MRI) in all patients on the first postoperative day. According to the control MRI data, the tumor was resected totally in 60% of patients, subtotally in 24% of patients, and partially in 16% of patients. In the early postoperative period, the development or

  19. Determination of Areas Susceptible to Landsliding Using Spatial Patterns of Rainfall from Tropical Rainfall Measuring Mission Data, Rio de Janeiro, Brazil

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    Renato Fontes Guimarães

    2017-10-01

    Full Text Available Spatial patterns of shallow landslide initiation reflect both spatial patterns of heavy rainfall and areas susceptible to mass movements. We determine the areas most susceptible to shallow landslide occurrence through the calculation of critical soil cohesion and spatial patterns of rainfall derived from TRMM (Tropical Rainfall Measuring Mission data for Paraty County, State of Rio de Janeiro, Brazil. Our methodology involved: (a creating the digital elevation model (DEM and deriving attributes such as slope and contributing area; (b incorporating spatial patterns of rainfall derived from TRMM into the shallow slope stability model SHALSTAB; and (c quantitative assessment of the correspondence of mapped landslide scars to areas predicted to be most prone to shallow landsliding. We found that around 70% of the landslide scars occurred in less than 10% of the study area identified as potentially unstable. The greatest concentration of landslides occurred in areas where the root strength of vegetation is an important contribution to slope stability in regions of orographically-enhanced rainfall on the coastal topographic flank. This approach helps quantify landslide hazards in areas with similar geomorphological characteristics, but different spatial patterns of rainfall.

  20. Defining Face Perception Areas in the Human Brain: A Large-Scale Factorial fMRI Face Localizer Analysis

    Science.gov (United States)

    Rossion, Bruno; Hanseeuw, Bernard; Dricot, Laurence

    2012-01-01

    A number of human brain areas showing a larger response to faces than to objects from different categories, or to scrambled faces, have been identified in neuroimaging studies. Depending on the statistical criteria used, the set of areas can be overextended or minimized, both at the local (size of areas) and global (number of areas) levels. Here…

  1. Musical structure is processed in "language" areas of the brain: a possible role for Brodmann Area 47 in temporal coherence.

    Science.gov (United States)

    Levitin, Daniel J; Menon, Vinod

    2003-12-01

    The neuroanatomical correlates of musical structure were investigated using functional magnetic neuroimaging (fMRI) and a unique stimulus manipulation involving scrambled music. The experiment compared brain responses while participants listened to classical music and scrambled versions of that same music. Specifically, the scrambled versions disrupted musical structure while holding low-level musical attributes constant, including the psychoacoustic features of the music such as pitch, loudness, and timbre. Comparing music to its scrambled counterpart, we found focal activation in the pars orbitalis region (Brodmann Area 47) of the left inferior frontal cortex, a region that has been previously closely associated with the processing of linguistic structure in spoken and signed language, and its right hemisphere homologue. We speculate that this particular region of inferior frontal cortex may be more generally responsible for processing fine-structured stimuli that evolve over time, not merely those that are linguistic.

  2. An improved FSL-FIRST pipeline for subcortical gray matter segmentation to study abnormal brain anatomy using quantitative susceptibility mapping (QSM).

    Science.gov (United States)

    Feng, Xiang; Deistung, Andreas; Dwyer, Michael G; Hagemeier, Jesper; Polak, Paul; Lebenberg, Jessica; Frouin, Frédérique; Zivadinov, Robert; Reichenbach, Jürgen R; Schweser, Ferdinand

    2017-06-01

    Accurate and robust segmentation of subcortical gray matter (SGM) nuclei is required in many neuroimaging applications. FMRIB's Integrated Registration and Segmentation Tool (FIRST) is one of the most popular software tools for automated subcortical segmentation based on T 1 -weighted (T1w) images. In this work, we demonstrate that FIRST tends to produce inaccurate SGM segmentation results in the case of abnormal brain anatomy, such as present in atrophied brains, due to a poor spatial match of the subcortical structures with the training data in the MNI space as well as due to insufficient contrast of SGM structures on T1w images. Consequently, such deviations from the average brain anatomy may introduce analysis bias in clinical studies, which may not always be obvious and potentially remain unidentified. To improve the segmentation of subcortical nuclei, we propose to use FIRST in combination with a special Hybrid image Contrast (HC) and Non-Linear (nl) registration module (HC-nlFIRST), where the hybrid image contrast is derived from T1w images and magnetic susceptibility maps to create subcortical contrast that is similar to that in the Montreal Neurological Institute (MNI) template. In our approach, a nonlinear registration replaces FIRST's default linear registration, yielding a more accurate alignment of the input data to the MNI template. We evaluated our method on 82 subjects with particularly abnormal brain anatomy, selected from a database of >2000 clinical cases. Qualitative and quantitative analyses revealed that HC-nlFIRST provides improved segmentation compared to the default FIRST method. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Brain functional network changes following Prelimbic area inactivation in a spatial memory extinction task.

    Science.gov (United States)

    Méndez-Couz, Marta; Conejo, Nélida M; Vallejo, Guillermo; Arias, Jorge L

    2015-01-01

    Several studies suggest a prefrontal cortex involvement during the acquisition and consolidation of spatial memory, suggesting an active modulating role at late stages of acquisition processes. Recently, we have reported that the prelimbic and infralimbic areas of the prefrontal cortex, among other structures, are also specifically involved in the late phases of spatial memory extinction. This study aimed to evaluate whether the inactivation of the prelimbic area of the prefrontal cortex impaired spatial memory extinction. For this purpose, male Wistar rats were implanted bilaterally with cannulae into the prelimbic region of the prefrontal cortex. Animals were trained during 5 consecutive days in a hidden platform task and tested for reference spatial memory immediately after the last training session. One day after completing the training task, bilateral infusion of the GABAA receptor agonist Muscimol was performed before the extinction protocol was carried out. Additionally, cytochrome c oxidase histochemistry was applied to map the metabolic brain activity related to the spatial memory extinction under prelimbic cortex inactivation. Results show that animals acquired the reference memory task in the water maze, and the extinction task was successfully completed without significant impairment. However, analysis of the functional brain networks involved by cytochrome oxidase activity interregional correlations showed changes in brain networks between the group treated with Muscimol as compared to the saline-treated group, supporting the involvement of the mammillary bodies at a the late stage in the memory extinction process. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Changes of brain and cerebrospinal fluid area with development in childhood on CT

    International Nuclear Information System (INIS)

    Nonaka, Chizuru; Hiraiwa, Mikio; Abe, Toshiaki; Fujii, Ryochi; Ohmi, Kazuhiko

    1980-01-01

    There have been reported about changes of the brain CT (Computed Tomography) findings with development in childhood. These reports have been applied with one dimensional measurement, and we previously reported that one dimensional measurement was insufficient for objective judgement of CT findings, compared with our two dimensional measurement. Brain CT were performed in sixty-six children (thirty-four males and thirty-two females, aged from ten-day-old to twelve-year-old). Two dimensional measurement were played on the slice through foramen of Monro. We measured intracranial area (IC), brain area (BA), ventricular area (VA), and bifrontal fluid collection area (BFC). IC and BA were increased with development, but VA had no obvious change. Increase of IC and BA were disclosed significantly in infancy and toddling period. BFC was decreased with development on the average, and invisible in many cases over three-year-old. Thus, in the cases under three-year-old there lay massive variation of BFC in size. About the relationship between large BFC and central coordination difficulty in infancy, we reported in the last number of this journal. Variation of BFC in the cases under three-year-old might be due to selection of our subjects, those including eighteen infants with central coordination difficulty. Index of BA (BA x 100/IC), VA (VA x 100/IC), and BFC (BFC x 100/IC) were well matched to changes of BA, VA, and BFC with development. This is the first report for application of two dimensional measurement in CT findings of children with development. (author)

  5. Landslide Susceptibility Mapping Based on Particle Swarm Optimization of Multiple Kernel Relevance Vector Machines: Case of a Low Hill Area in Sichuan Province, China

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    Yongliang Lin

    2016-10-01

    Full Text Available In this paper, we propose a multiple kernel relevance vector machine (RVM method based on the adaptive cloud particle swarm optimization (PSO algorithm to map landslide susceptibility in the low hill area of Sichuan Province, China. In the multi-kernel structure, the kernel selection problem can be solved by adjusting the kernel weight, which determines the single kernel contribution of the final kernel mapping. The weights and parameters of the multi-kernel function were optimized using the PSO algorithm. In addition, the convergence speed of the PSO algorithm was increased using cloud theory. To ensure the stability of the prediction model, the result of a five-fold cross-validation method was used as the fitness of the PSO algorithm. To verify the results, receiver operating characteristic curves (ROC and landslide dot density (LDD were used. The results show that the model that used a heterogeneous kernel (a combination of two different kernel functions had a larger area under the ROC curve (0.7616 and a lower prediction error ratio (0.28% than did the other types of kernel models employed in this study. In addition, both the sum of two high susceptibility zone LDDs (6.71/100 km2 and the sum of two low susceptibility zone LDDs (0.82/100 km2 demonstrated that the landslide susceptibility map based on the heterogeneous kernel model was closest to the historical landslide distribution. In conclusion, the results obtained in this study can provide very useful information for disaster prevention and land-use planning in the study area.

  6. Susceptibility of Different Populations of Nilaparvata lugens from Major Rice Growing Areas of Karnataka, India to Different Groups of Insecticides

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    Y.S. BASANTH

    2013-09-01

    Full Text Available Susceptibility to insecticides was investigated by collecting field populations of brown planthopper from different locations of southern Karnataka, India (Gangavati, Kathalagere, Kollegala, Soraba and Mandya. All the field populations differed in their susceptibility to insecticides. In general, Soraba and Mandya populations were more susceptible to insecticides compared to Gangavati and Kathalagere populations. The resistance ratios varied greatly among the populations viz., chlorpyriphos (1.13- to 16.82-fold, imidacloprid (0.53- to 13.50-fold, acephate (1.34- to 5.32-fold, fipronil (1.13- to 4.06-fold, thiamethoxam (1.01- to 2.19-fold, clothianidin (1.92- to 4.86-fold, dinotefuran (0.82- to 2.22-fold, buprofezin (1.06- to 5.43-fold and carbofuran (0.41- to 2.17-fold. The populations from Gangavati, Kathalagere and Kollegala exhibited higher resistance to some of the old insecticides and low resistance to new molecules.

  7. Susceptibility to cigarette smoking among secondary and high school students from a socially disadvantaged rural area in Poland.

    Science.gov (United States)

    Polańska, Kinga; Wojtysiak, Piotr; Bąk-Romaniszyn, Leokadia; Kaleta, Dorota

    2016-01-01

    To prevent adolescents from becoming smokers, it is essential to understand factors that cause them to become susceptible to smoking (SS). The aim of this study was to examine association between individual and school characteristics and susceptibility to smoking initiation and experimentation in the youth. We collected cross-sectional survey data from students aged 13-19 years attending 21 schools from Piotrkowski district. Of 4050 students, 3552 respondents, including 2508 non-smokers, filled in an anonymous, self-administered questionnaire adapted from the Global Youth Tobacco Survey. The univariate and multivariate logistic regression analyses were applied to the study factors linked to SS among the never and ever smoking youth. About 22 % of the never smoking and 57 % of the ever smoking students were found to be vulnerable to smoking. The youth who were males (OR = 1.4; p = 0.001), who were older (OR = 1.1; p = 0.002) and those, whose mothers had medium (OR = 1.8; p smoking compared to the females, younger ones and those whose mothers were highly educated. The students who lived in households with no smoking ban (OR = 1.4; p = 0.001) and those who had ever tried cigarettes (OR = 3.5; p smoking comparing to those who indicated smoke-free home and who had never smoked. In addition, having smoking friends (OR = 2.3; p smoking on the premises of the school (OR = 1.8; p smoking girls more attractive than the non-smokers (OR = 3.8; p smoking susceptibility. Finally, the separate analysis among the never smokers indicated that no school training on tobacco harm (OR = 1.3; p = 0.04) is the additional significant factor for susceptibility to smoking initiation. SS is prevalent in secondary and high school students in Poland. Personal, social and environmental factors are strongly correlated with SS. When addressing the youth, efforts should be focused on the groups at risk, with a comprehensive approach

  8. Association of change in brain structure to objectively measured physical activity and sedentary behavior in older adults: Age, Gene/Environment Susceptibility-Reykjavik Study.

    Science.gov (United States)

    Arnardottir, Nanna Yr; Koster, Annemarie; Domelen, Dane R Van; Brychta, Robert J; Caserotti, Paolo; Eiriksdottir, Gudny; Sverrisdottir, Johanna E; Sigurdsson, Sigurdur; Johannsson, Erlingur; Chen, Kong Y; Gudnason, Vilmundur; Harris, Tamara B; Launer, Lenore J; Sveinsson, Thorarinn

    2016-01-01

    Many studies have examined the hypothesis that greater participation in physical activity (PA) is associated with less brain atrophy. Here we examine, in a sub-sample (n=352, mean age 79.1 years) of the Age, Gene/Environment Susceptibility-Reykjavik Study cohort, the association of the baseline and 5-year change in magnetic resonance imaging (MRI)-derived volumes of gray matter (GM) and white matter (WM) to active and sedentary behavior (SB) measured at the end of the 5-year period by a hip-worn accelerometer for seven consecutive days. More GM (β=0.11; p=0.044) and WM (β=0.11; p=0.030) at baseline was associated with more total physical activity (TPA). Also, when adjusting for baseline values, the 5-year change in GM (β=0.14; p=0.0037) and WM (β=0.11; p=0.030) was associated with TPA. The 5-year change in WM was associated with SB (β=-0.11; p=0.0007). These data suggest that objectively measured PA and SB late in life are associated with current and prior cross-sectional measures of brain atrophy, and that change over time is associated with PA and SB in expected directions. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. High-field, high-resolution, susceptibility-weighted magnetic resonance imaging: improved image quality by addition of contrast agent and higher field strength in patients with brain tumors

    International Nuclear Information System (INIS)

    Pinker, K.; Noebauer-Huhmann, I.M.; Szomolanyi, P.; Weber, M.; Grabner, G.; Trattnig, S.; Stavrou, I.; Knosp, E.; Hoeftberger, R.; Stadlbauer, A.

    2008-01-01

    To demonstrate intratumoral susceptibility effects in malignant brain tumors and to assess visualization of susceptibility effects before and after administration of the paramagnetic contrast agent MultiHance (gadobenate dimeglumine; Bracco Imaging), an agent known to have high relaxivity, with respect to susceptibility effects, image quality, and reduction of scan time. Included in the study were 19 patients with malignant brain tumors who underwent high-resolution, susceptibility-weighted (SW) MR imaging at 3 T before and after administration of contrast agent. In all patients, Multihance was administered intravenously as a bolus (0.1 mmol/kg body weight). MR images were individually evaluated by two radiologists with previous experience in the evaluation of pre- and postcontrast 3-T SW MR images with respect to susceptibility effects, image quality, and reduction of scan time. In the 19 patients 21 tumors were diagnosed, of which 18 demonstrated intralesional susceptibility effects both in pre- and postcontrast SW images, and 19 demonstrated contrast enhancement in both SW images and T1-weighted spin-echo MR images. Conspicuity of susceptibility effects and image quality were improved in postcontrast images compared with precontrast images and the scan time was also reduced due to decreased TE values from 9 min (precontrast) to 7 min (postcontrast). The intravenous administration of MultiHance, an agent with high relaxivity, allowed a reduction of scan time from 9 min to 7 min while preserving excellent susceptibility effects and image quality in SW images obtained at 3 T. Contrast enhancement and intralesional susceptibility effects can be assessed in one sequence. (orig.)

  10. SPECT assessment of brain activation induced by caffeine: no effect on areas involved in dependence.

    Science.gov (United States)

    Nehlig, Astrid; Armspach, Jean-Paul; Namer, Izzie J

    2010-01-01

    Caffeine is not considered addictive, and in animals it does not trigger metabolic increases or dopamine release in brain areas involved in reinforcement and reward. Our objective was to measure caffeine effects on cerebral perfusion in humans using single photon emission computed tomography with a specific focus on areas of reinforcement and reward. Two groups of nonsmoking subjects were studied, one with a low (8 subjects) and one with a high (6 subjects) daily coffee consumption. The subjects ingested 3 mg/kg caffeine or placebo in a raspberry-tasting drink, and scans were performed 45 min after ingestion. A control group of 12 healthy volunteers receiving no drink was also studied. Caffeine consumption led to a generalized, statistically nonsignificant perfusion decrease of 6% to 8%, comparable in low and high consumers. Compared with controls, low consumers displayed neuronal activation bilaterally in inferior frontal gyrus-anterior insular cortex and uncus, left internal parietal cortex, right lingual gyrus, and cerebellum. In high consumers, brain activation occurred bilaterally only in hypothalamus. Thus, on a background of widespread low-amplitude perfusion decrease, caffeine activates a few regions mainly involved in the control of vigilance, anxiety, and cardiovascular regulation, but does not affect areas involved in reinforcing and reward.

  11. Landslide susceptibility modeling in a landslide prone area in Mazandarn Province, north of Iran: a comparison between GLM, GAM, MARS, and M-AHP methods

    Science.gov (United States)

    Pourghasemi, Hamid Reza; Rossi, Mauro

    2017-10-01

    Landslides are identified as one of the most important natural hazards in many areas throughout the world. The essential purpose of this study is to compare general linear model (GLM), general additive model (GAM), multivariate adaptive regression spline (MARS), and modified analytical hierarchy process (M-AHP) models and assessment of their performances for landslide susceptibility modeling in the west of Mazandaran Province, Iran. First, landslides were identified by interpreting aerial photographs, and extensive field works. In total, 153 landslides were identified in the study area. Among these, 105 landslides were randomly selected as training data (i.e. used in the models training) and the remaining 48 (30 %) cases were used for the validation (i.e. used in the models validation). Afterward, based on a deep literature review on 220 scientific papers (period between 2005 and 2012), eleven conditioning factors including lithology, land use, distance from rivers, distance from roads, distance from faults, slope angle, slope aspect, altitude, topographic wetness index (TWI), plan curvature, and profile curvature were selected. The Certainty Factor (CF) model was used for managing uncertainty in rule-based systems and evaluation of the correlation between the dependent (landslides) and independent variables. Finally, the landslide susceptibility zonation was produced using GLM, GAM, MARS, and M-AHP models. For evaluation of the models, the area under the curve (AUC) method was used and both success and prediction rate curves were calculated. The evaluation of models for GLM, GAM, and MARS showed 90.50, 88.90, and 82.10 % for training data and 77.52, 70.49, and 78.17 % for validation data, respectively. Furthermore, The AUC value of the produced landslide susceptibility map using M-AHP showed a training value of 77.82 % and validation value of 82.77 % accuracy. Based on the overall assessments, the proposed approaches showed reasonable results for landslide

  12. Assessing the susceptibility to contamination of two aquifer systems used for public water supply in the Modesto and Fresno metropolitan areas, California, 2001 and 2002

    Science.gov (United States)

    Wright, Michael T.; Belitz, Kenneth; Johnson, Tyler D.

    2004-01-01

    Ground-water samples were collected from 90 active public supply wells in the Fresno and Modesto metropolitan areas as part of the California Aquifer Susceptibility (CAS) program. The CAS program was formed to examine the susceptibility to contamination of aquifers that are tapped by public supply wells to serve the citizens of California. The objectives of the program are twofold: (1) to evaluate the quality of ground water used for public supply using volatile organic compound (VOC) concentrations in ground-water samples and (2) to determine if the occurrence and distribution of low level VOCs in ground water and characteristics, such as land use, can be used to predict aquifer susceptibility to contamination from anthropogenic activities occurring at, or near, land surface. An evaluation was made of the relation between VOC occurrence and the explanatory variables: depth to the top of the uppermost well perforation, land use, relative ground-water age, high nitrate concentrations, density of leaking underground fuel tanks (LUFT), and source of recharge water. VOCs were detected in 92 percent of the wells sampled in Modesto and in 72 percent of the wells sampled in Fresno. Trihalomethanes (THM) and solvents were frequently detected in both study areas. Conversely, the gasoline components?benzene, toluene ethylbenzene, and xylenes (BTEX)?were rarely, if at all, detected, even though LUFTs were scattered throughout both study areas. The rare occurrence of BTEX compounds may be the result of their low solubility and labile nature in the subsurface environment. Samples were analyzed for 85 VOCs; 25 were detected in at least one sample. The concentrations of nearly all VOCs detected were at least an order of magnitude below action levels set by drinking water standards. Concentrations of four VOCs exceeded federal and state maximum contaminant levels (MCL): the solvent trichloroethylene (TCE) and the fumigant 1, 2-dibromo-3-chloropropane (DBCP) in Fresno, and the

  13. High-resolution characterisation of the aging brain using simultaneous quantitative susceptibility mapping (QSM) and R2* measurements at 7T.

    Science.gov (United States)

    Betts, Matthew J; Acosta-Cabronero, Julio; Cardenas-Blanco, Arturo; Nestor, Peter J; Düzel, Emrah

    2016-09-01

    Quantitative susceptibility mapping (QSM) has recently emerged as a novel magnetic resonance imaging (MRI) method to detect non-haem iron deposition, calcifications, demyelination and vascular lesions in the brain. It has been suggested that QSM is more sensitive than the more conventional quantifiable MRI measure, namely the transverse relaxation rate, R2*. Here, we conducted the first high-resolution, whole-brain, simultaneously acquired, comparative study of the two techniques using 7Tesla MRI. We asked which of the two techniques would be more sensitive to explore global differences in tissue composition in elderly adults relative to young subjects. Both QSM and R2* revealed strong age-related differences in subcortical regions, hippocampus and cortical grey matter, particularly in superior frontal regions, motor/premotor cortices, insula and cerebellar regions. Within the basal ganglia system-but also hippocampus and cerebellar dentate nucleus-, QSM was largely in agreement with R2* with the exception of the globus pallidus. QSM, however, provided superior anatomical contrast and revealed age-related differences in the thalamus and in white matter, which were otherwise largely undetected by R2* measurements. In contrast, in occipital cortex, age-related differences were much greater with R2* compared to QSM. The present study, therefore, demonstrated that in vivo QSM using ultra-high field MRI provides a novel means to characterise age-related differences in the human brain, but also combining QSM and R2* using multi-gradient recalled echo imaging can potentially provide a more complete picture of mineralisation, demyelination and/or vascular alterations in aging and disease. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Combining Functional Neuroimaging with Off-Line Brain Stimulation: Modulation of Task-Related Activity in Language Areas

    Science.gov (United States)

    Andoh, Jamila; Paus, Tomas

    2011-01-01

    Repetitive TMS (rTMS) provides a noninvasive tool for modulating neural activity in the human brain. In healthy participants, rTMS applied over the language-related areas in the left hemisphere, including the left posterior temporal area of Wernicke (LTMP) and inferior frontal area of Broca, have been shown to affect performance on word…

  15. Susceptibility to cigarette smoking among secondary and high school students from a socially disadvantaged rural area in Poland

    Directory of Open Access Journals (Sweden)

    Kinga Polańska

    2016-08-01

    SS is prevalent in secondary and high school students in Poland. Personal, social and environmental factors are strongly correlated with SS. When addressing the youth, efforts should be focused on the groups at risk, with a comprehensive approach including multiple factors and involving school personnel, parents and the group leaders in tobacco control activities. Projects aimed at changing social norms around smoking and providing the youth with knowledge and skills to resist smoking are also needed. This may help to implement an effective approach to prevent smoking susceptibility and initiation of tobacco use among the youth.

  16. Mapping flood and flooding potential indices: a methodological approach to identifying areas susceptible to flood and flooding risk. Case study: the Prahova catchment (Romania)

    Science.gov (United States)

    Zaharia, Liliana; Costache, Romulus; Prăvălie, Remus; Ioana-Toroimac, Gabriela

    2017-04-01

    Given that floods continue to cause yearly significant worldwide human and material damages, flood risk mitigation is a key issue and a permanent challenge in developing policies and strategies at various spatial scales. Therefore, a basic phase is elaborating hazard and flood risk maps, documents which are an essential support for flood risk management. The aim of this paper is to develop an approach that allows for the identification of flash-flood and flood-prone susceptible areas based on computing and mapping of two indices: FFPI (Flash-Flood Potential Index) and FPI (Flooding Potential Index). These indices are obtained by integrating in a GIS environment several geographical variables which control runoff (in the case of the FFPI) and favour flooding (in the case of the FPI). The methodology was applied in the upper (mountainous) and middle (hilly) catchment of the Prahova River, a densely populated and socioeconomically well-developed area which has been affected repeatedly by water-related hazards over the past decades. The resulting maps showing the spatialization of the FFPI and FPI allow for the identification of areas with high susceptibility to flashfloods and flooding. This approach can provide useful mapped information, especially for areas (generally large) where there are no flood/hazard risk maps. Moreover, the FFPI and FPI maps can constitute a preliminary step for flood risk and vulnerability assessment.

  17. CRMP5 regulates generation and survival of newborn neurons in olfactory and hippocampal neurogenic areas of the adult mouse brain.

    Directory of Open Access Journals (Sweden)

    Alexandra Veyrac

    Full Text Available The Collapsin Response Mediator Proteins (CRMPS are highly expressed in the developing brain, and in adult brain areas that retain neurogenesis, ie: the olfactory bulb (OB and the dentate gyrus (DG. During brain development, CRMPs are essentially involved in signaling of axon guidance and neurite outgrowth, but their functions in the adult brain remain largely unknown. CRMP5 has been initially identified as the target of auto-antibodies involved in paraneoplasic neurological diseases and further implicated in a neurite outgrowth inhibition mediated by tubulin binding. Interestingly, CRMP5 is also highly expressed in adult brain neurogenic areas where its functions have not yet been elucidated. Here we observed in both neurogenic areas of the adult mouse brain that CRMP5 was present in proliferating and post-mitotic neuroblasts, while they migrate and differentiate into mature neurons. In CRMP5(-/- mice, the lack of CRMP5 resulted in a significant increase of proliferation and neurogenesis, but also in an excess of apoptotic death of granule cells in the OB and DG. These findings provide the first evidence that CRMP5 is involved in the generation and survival of newly generated neurons in areas of the adult brain with a high level of activity-dependent neuronal plasticity.

  18. Brain perfusion SPECT with Brodmann areas analysis in differentiating frontotemporal dementia subtypes.

    Science.gov (United States)

    Valotassiou, Varvara; Papatriantafyllou, John; Sifakis, Nikolaos; Tzavara, Chara; Tsougos, Ioannis; Psimadas, Dimitrios; Kapsalaki, Eftychia; Fezoulidis, Ioannis; Hadjigeorgiou, George; Georgoulias, Panagiotis

    2014-01-01

    Despite the known validity of clinical diagnostic criteria, significant overlap of clinical symptoms between Frontotemporal dementia (FTD) subtypes exists in several cases, resulting in great uncertainty of the diagnostic boundaries. We evaluated the perfusion between FTD subtypes using brain perfusion (99m)Tc-HMPAO SPECT with Brodmann areas (BA) mapping. NeuroGam software was applied on single photon emission computed tomographic (SPECT) studies for the semi-quantitative evaluation of perfusion in BA and the comparison with the software's normal database. We studied 91 consecutive FTD patients: 21 with behavioural variants (bvFTD), 39 with language variants (lvFTD) [12 with progressive non-fluent aphasia (PNFA), 27 with semantic dementia (SD)], and 31 patients with progressive supranuclear palsy (PSP)/corticobasal degeneration (CBD). Stepwise logistic regression analyses showed that the BA 28L and 32R could independently differentiate bvFTD from lvFTD, while the BA 8R and 25R could discriminate bvFTD from SD and PNFA, respectively. Additionally, BA 7R and 32R were found to discriminate bvFTD from CBD/PSP. The only BA that could differentiate SD from PNFA was 6L. BA 6R and 20L were found to independently differentiate CBD/PSP from lvFTD. Moreover, BA 20L and 22R could discriminate CBD/PSP from PNFA, while BA 6R, 20L and 45R were found to independently discriminate CBD/PSP from SD. Brain perfusion SPECT with BA mapping can be a useful additional tool in differentiating FTD variants by improving the definition of brain areas that are specifically implicated, resulting in a more accurate differential diagnosis in atypical or uncertain forms of FTD.

  19. Reading a suspenseful literary text activates brain areas related to social cognition and predictive inference.

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    Moritz Lehne

    Full Text Available Stories can elicit powerful emotions. A key emotional response to narrative plots (e.g., novels, movies, etc. is suspense. Suspense appears to build on basic aspects of human cognition such as processes of expectation, anticipation, and prediction. However, the neural processes underlying emotional experiences of suspense have not been previously investigated. We acquired functional magnetic resonance imaging (fMRI data while participants read a suspenseful literary text (E.T.A. Hoffmann's "The Sandman" subdivided into short text passages. Individual ratings of experienced suspense obtained after each text passage were found to be related to activation in the medial frontal cortex, bilateral frontal regions (along the inferior frontal sulcus, lateral premotor cortex, as well as posterior temporal and temporo-parietal areas. The results indicate that the emotional experience of suspense depends on brain areas associated with social cognition and predictive inference.

  20. Anopheles darlingi and Anopheles marajoara (Diptera: Culicidae susceptibility to pyrethroids in an endemic area of the Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    Allan Kardec Ribeiro Galardo

    2015-12-01

    Full Text Available Abstract: INTRODUCTION: This study aimed to evaluate the susceptibility of Anopheles darlingi Root (1926 and Anopheles marajoara Galvão & Damasceno (1942 to pyrethroids used by the National Malaria Control Program in Brazil. METHODS: Mosquitoes from Amapá, Brazilian Amazon, were assessed for resistance to cypermethrin, deltamethrin, and alpha-cypermethrin. Insecticide-impregnated bottles were used as suggested by the CDC/Atlanta. RESULTS: Diagnostic dose for Anopheles darlingi was 12.5µg/bottle during 30 min of exposure. Concentrations for Anopheles marajoara were 20µg/bottle of cypermethrin and deltamethrin and 12.5µg/bottle of alpha-cypermethrin. CONCLUSIONS : No resistance was recorded for Anopheles darlingi , but Anopheles marajoara requires attention.

  1. Alzheimer's disease susceptibility genes APOE and TOMM40, and brain white matter integrity in the Lothian Birth Cohort 1936.

    Science.gov (United States)

    Lyall, Donald M; Harris, Sarah E; Bastin, Mark E; Muñoz Maniega, Susana; Murray, Catherine; Lutz, Michael W; Saunders, Ann M; Roses, Allen D; Valdés Hernández, Maria del C; Royle, Natalie A; Starr, John M; Porteous, David J; Wardlaw, Joanna M; Deary, Ian J

    2014-06-01

    Apolipoprotein E (APOE) ε genotype has previously been significantly associated with cognitive, brain imaging, and Alzheimer's disease-related phenotypes (e.g., age of onset). In the TOMM40 gene, the rs10524523 ("523") variable length poly-T repeat polymorphism has more recently been associated with similar ph/enotypes, although the allelic directions of these associations have varied between initial reports. Using diffusion magnetic resonance imaging tractography, the present study aimed to investigate whether there are independent effects of apolipoprotein E (APOE) and TOMM40 genotypes on human brain white matter integrity in a community-dwelling sample of older adults, the Lothian Birth Cohort 1936 (mean age = 72.70 years, standard deviation = 0.74, N approximately = 640-650; for most analyses). Some nominally significant effects were observed (i.e., covariate-adjusted differences between genotype groups at p vs. absence) were found in the right ventral cingulum and left inferior longitudinal fasciculus. To test for biologically independent effects of the TOMM40 523 repeat, participants were stratified into APOE genotype subgroups, so that any significant effects could not be attributed to APOE variation. In participants with the APOE ε3/ε4 genotype, effects of TOMM40 523 status were found in the left uncinate fasciculus, left rostral cingulum, left ventral cingulum, and a general factor of white matter integrity. In all 4 of these tractography measures, carriers of the TOMM40 523 "short" allele showed lower white matter integrity when compared with carriers of the "long" and "very-long" alleles. Most of these effects survived correction for childhood intelligence test scores and vascular disease history, though only the effect of TOMM40 523 on the left ventral cingulum integrity survived correction for false discovery rate. The effects of APOE in this older population are more specific and restricted compared with those reported in previous studies, and the

  2. Area, age and gender dependence of the nucleoside system in the brain: a review of current literature.

    Science.gov (United States)

    Kovács, Zsolt; Juhász, Gábor; Palkovits, Miklós; Dobolyi, Arpád; Kékesi, Katalin A

    2011-01-01

    Nucleosides, such as uridine, inosine, guanosine and adenosine, may participate in the regulation of sleep, cognition, memory and nociception, the suppression of seizures, and have also been suggested to play a role in the pathophysiology of some neurodegenerative and neuropsychiatric diseases. Under pathological conditions, levels of nucleosides change extremely in the brain, indicating their participation in the pathophysiology of disorders like Alzheimer's disease, Parkinson's disease and schizophrenia. These findings have resulted in an increasing attention to the roles of nucleosides in the central nervous system. The specific effects of nucleosides depend on the expression of their receptors and transporters in neuronal and glial cells, as well as their extracellular concentrations in the brain. A complex interlinked metabolic network and transporters of nucleosides may balance nucleoside levels in the brain tissue under normal conditions and enable the fine modulation of neuronal and glial processes via nucleoside receptor signaling mechanisms. Brain levels of nucleosides were found to vary when measured in a variety of different brain regions. In addition, nucleoside levels also depend on age and gender. Furthermore, distributions of nucleoside transporters and receptors as well as nucleoside metabolic enzyme activities demonstrate the area, age and gender dependence of the nucleoside system, suggesting different roles of nucleosides in functionally different brain areas. The aim of this review article is to summarize our present knowledge of the area-, age- and gender-dependent distribution of nucleoside levels, nucleoside metabolic enzyme activity, nucleoside receptors and nucleoside transporters in the brain.

  3. Dorsal and ventral working memory-related brain areas support distinct processes in contextual cueing.

    Science.gov (United States)

    Manginelli, Angela A; Baumgartner, Florian; Pollmann, Stefan

    2013-02-15

    Behavioral evidence suggests that the use of implicitly learned spatial contexts for improved visual search may depend on visual working memory resources. Working memory may be involved in contextual cueing in different ways: (1) for keeping implicitly learned working memory contents available during search or (2) for the capture of attention by contexts retrieved from memory. We mapped brain areas that were modulated by working memory capacity. Within these areas, activation was modulated by contextual cueing along the descending segment of the intraparietal sulcus, an area that has previously been related to maintenance of explicit memories. Increased activation for learned displays, but not modulated by the size of contextual cueing, was observed in the temporo-parietal junction area, previously associated with the capture of attention by explicitly retrieved memory items, and in the ventral visual cortex. This pattern of activation extends previous research on dorsal versus ventral stream functions in memory guidance of attention to the realm of attentional guidance by implicit memory. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Sensory competition in the face processing areas of the human brain.

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    Krisztina Nagy

    Full Text Available The concurrent presentation of multiple stimuli in the visual field may trigger mutually suppressive interactions throughout the ventral visual stream. While several studies have been performed on sensory competition effects among non-face stimuli relatively little is known about the interactions in the human brain for multiple face stimuli. In the present study we analyzed the neuronal basis of sensory competition in an event-related functional magnetic resonance imaging (fMRI study using multiple face stimuli. We varied the ratio of faces and phase-noise images within a composite display with a constant number of peripheral stimuli, thereby manipulating the competitive interactions between faces. For contralaterally presented stimuli we observed strong competition effects in the fusiform face area (FFA bilaterally and in the right lateral occipital area (LOC, but not in the occipital face area (OFA, suggesting their different roles in sensory competition. When we increased the spatial distance among pairs of faces the magnitude of suppressive interactions was reduced in the FFA. Surprisingly, the magnitude of competition depended on the visual hemifield of the stimuli: ipsilateral stimulation reduced the competition effects somewhat in the right LOC while it increased them in the left LOC. This suggests a left hemifield dominance of sensory competition. Our results support the sensory competition theory in the processing of multiple faces and suggests that sensory competition occurs in several cortical areas in both cerebral hemispheres.

  5. The relationship between reproductive state and "sexually" dimorphic brain areas in sexually reproducing and parthenogenetic whiptail lizards.

    Science.gov (United States)

    Wade, J; Crews, D

    1991-07-22

    The anterior hypothalamus-preoptic area and ventromedial hypothalamus are sexually dimorphic in the reproductively active whiptail lizard Cnemidophorus inornatus. The anterior hypothalamus-preoptic area, which is involved in the control of male-typical copulatory behaviors, is larger in males, whereas the ventromedial hypothalamus, which is involved in the control of female-typical receptivity, is larger in females. In the parthenogenetic whiptail lizard C. uniparens, which is a direct descendant of C. inornatus and exhibits both male-like and female-like pseudosexual behaviors, both brain areas are comparable in size to those of female C. inornatus. This study was conducted to determine whether these brain areas change in size in either species or sex during a time of year when these animals are reproductively inactive, or after removal of the gonads. In male C. inornatus both brain areas changed during reproductive inactivity (either seasonally or surgically induced) and became equivalent to the size characteristic of reproductively active female C. inornatus. When corrected for brain size, the anterior hypothalamus-preoptic area was significantly smaller in intact hibernating and castrated males than in intact males from the summer breeding season. Conversely, the ventromedial hypothalamus was significantly larger in intact hibernating and castrated males than in intact males from the summer breeding season. The two brain areas were not significantly different among the groups of female C. inornatus or parthenogenetic C. uniparens. These results suggest that 1) the brain of whiptail lizards may differentiate seasonally and 2) the female state may be a neutral one to which the male brain reverts during reproductive inactivity.

  6. Selective insulin resistance in homeostatic and cognitive control brain areas in overweight and obese adults.

    Science.gov (United States)

    Kullmann, Stephanie; Heni, Martin; Veit, Ralf; Scheffler, Klaus; Machann, Jürgen; Häring, Hans-Ulrich; Fritsche, Andreas; Preissl, Hubert

    2015-06-01

    Impaired brain insulin action has been linked to obesity, type 2 diabetes, and neurodegenerative diseases. To date, the central nervous effects of insulin in obese humans still remain ill defined, and no study thus far has evaluated the specific brain areas affected by insulin resistance. In 25 healthy lean and 23 overweight/obese participants, we performed magnetic resonance imaging to measure cerebral blood flow (CBF) before and 15 and 30 min after application of intranasal insulin or placebo. Additionally, participants explicitly rated pictures of high-caloric savory and sweet food 60 min after the spray for wanting and liking. In response to insulin compared with placebo, we found a significant CBF decrease in the hypothalamus in both lean and overweight/obese participants. The magnitude of this response correlated with visceral adipose tissue independent of other fat compartments. Furthermore, we observed a differential response in the lean compared with the overweight/obese group in the prefrontal cortex, resulting in an insulin-induced CBF reduction in lean participants only. This prefrontal cortex response significantly correlated with peripheral insulin sensitivity and eating behavior measures such as disinhibition and food craving. Behaviorally, we were able to observe a significant reduction for the wanting of sweet foods after insulin application in lean men only. Brain insulin action was selectively impaired in the prefrontal cortex in overweight and obese adults and in the hypothalamus in participants with high visceral adipose tissue, potentially promoting an altered homeostatic set point and reduced inhibitory control contributing to overeating behavior. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  7. Cyto- and receptor architecture of area 32 in human and macaque brains.

    Science.gov (United States)

    Palomero-Gallagher, Nicola; Zilles, Karl; Schleicher, Axel; Vogt, Brent A

    2013-10-01

    Human area 32 plays crucial roles in emotion and memory consolidation. It has subgenual (s32), pregenual (p32), dorsal, and midcingulate components. We seek to determine whether macaque area 32 has subgenual and pregenual subdivisions and the extent to which they are comparable to those in humans by means of NeuN immunohistochemistry and multireceptor analysis of laminar profiles. The macaque has areas s32 and p32. In s32, layer IIIa/b neurons are larger than those of layer IIIc. This relationship is reversed in p32. Layer Va is thicker and Vb thinner in s32. Area p32 contains higher kainate, benzodiazepine (BZ), and serotonin (5-HT)1A but lower N-methyl-D-aspartate (NMDA) and α2 receptor densities. Most differences were found in layers I, II, and VI. Together, these differences support the dual nature of macaque area 32. Comparative analysis of human and macaque s32 and p32 supports equivalences in cyto- and receptor architecture. Although there are differences in mean areal receptor densities, there are considerable similarities at the layer level. Laminar receptor distribution patterns in each area are comparable in the two species in layers III-Va for kainate, NMDA, γ-aminobutyric acid (GABA)B , BZ, and 5-HT1A receptors. Multivariate statistical analysis of laminar receptor densities revealed that human s32 is more similar to macaque s32 and p32 than to human p32. Thus, macaque 32 is more complex than hitherto known. Our data suggest a homologous neural architecture in anterior cingulate s32 and p32 in human and macaque brains. © 2013 Wiley Periodicals, Inc.

  8. Proteomic Analysis of Parkin Isoforms Expression in Different Rat Brain Areas.

    Science.gov (United States)

    D'Amico, Agata Grazia; Maugeri, Grazia; Reitano, Rita; Cavallaro, Sebastiano; D'Agata, Velia

    2016-10-01

    PARK2 gene's mutations are related to the familial form of juvenile Parkinsonism, also known as the autosomic recessive juvenile Parkinsonism. This gene encodes for parkin, a 465-amino acid protein. To date, a large number of parkin isoforms, generated by an alternative splicing mechanism, have been described. Currently, Gene Bank lists 27 rat PARK2 transcripts, which matches to 20 exclusive parkin alternative splice variants. Despite the existence of these isoforms, most of the studies carried out so far, have been focused only on the originally cloned parkin. In this work we have analyzed the expression profile of parkin isoforms in some rat brain areas including prefrontal cortex, hippocampus, substantia nigra and cerebellum. To discriminate among these isoforms, we detected their localization through the use of two antibodies that are able to identify different domains of the parkin canonical sequence. Our analysis has revealed that at least fourteen parkin isoforms are expressed in rat brain with a various distribution in the regions analyzed. Our study might help to elucidate the pathophysiological role of these proteins in the central nervous system.

  9. Antibiotic susceptibility profile of bacteria isolated from natural sources of water from rural areas of East Sikkim

    Directory of Open Access Journals (Sweden)

    Shubra Poonia

    2014-01-01

    Full Text Available Background: Contamination of water, food, and environment with antibiotic-resistant bacteria poses a serious public health issue. Objective: The objective was to study the bacterial pollution of the natural sources of water in east Sikkim and to determine the antimicrobial profile of the bacterial isolates. Materials and Methods: A total of 225 samples, 75 each during winter, summer, and monsoon season were collected from the same source in every season for bacteriological analysis by membrane filtration method. Antibiotic susceptibility test was performed using standard disc diffusion method. Results: A total of 19 bacterial species of the genera Escherichia, Klebsiella, Proteus, Salmonella, Shigella, Enterobacter, Citrobacter, Morganella, Pseudomonas, Acinetobacter, Flavobacterium, and Serratia were isolated and their antimicrobial sensitivity tested. Generally, most bacterial isolates except Salmonella and Shigella species were found resistant to commonly used antibiotics such as ampicillin (57.5%, trimethoprim/sulfamethoxaole (39.1%, amoxicillin/clavulanic acid (37.4%, cefixime (34.5%, tetracycline (29.1%, ceftazidime (26.3%, ofloxacin (25.9%, amikacin (8.7%, and gentamicin (2.7% but sensitive to imipenem and piperacillin/tazobactam. Conclusion: Natural sources of water in east Sikkim are grossly contaminated with bacteria including enteropathogens. The consumption of untreated water from these sources might pose health risk to consumers.

  10. Age-related susceptibility to infection with diarrheagenic E. coli in infants from peri-urban areas of Lima, Peru

    Science.gov (United States)

    Ochoa, Theresa J.; Ecker, Lucie; Barletta, Francesca; Mispireta, Mónica L.; Gil, Ana I.; Contreras, Carmen; Molina, Margarita; Amemiya, Isabel; Verastegui, Hector; Hall, Eric R.; Cleary, Thomas G.; Lanata, Claudio F.

    2009-01-01

    Background Diarrheagenic E. coli are being recognized as important pediatric enteropathogens worldwide. However, it is unclear whether there are differences in age-related susceptibility to specific agents, especially among infants. Methods We conducted a passive surveillance diarrhea cohort study of 1034 children from 2 to 12 months of age in Lima, Perú. Control stool samples were collected from randomly selected children without diarrhea. All samples were analyzed for common enteric pathogens and for the diarrheagenic E. coli by a multiplex real-time PCR. Results The most commonly isolated pathogens from 1065 diarrheal episodes were the diarrheagenic E. coli (31%), including enteroaggregative (15.1%) and enteropathogenic E. coli (EPEC) (7.6%). Diarrheagenic E. coli, Campylobacter and rotavirus were more frequently isolated from infants ≥ 6m. Diffusely adherent E. coli and enterotoxigenic E. coli (ETEC) were more frequently isolated in diarrheal samples than in controls in older infants (pfactors and with increased exposure to contaminated food and water. PMID:19857163

  11. Antisocial and seizure susceptibility phenotypes in an animal model of epilepsy are normalized by impairment of brain corticotropin-releasing factor.

    Science.gov (United States)

    Turner, Laura H; Lim, Chen E; Heinrichs, Stephen C

    2007-02-01

    Social interaction phenotyping is an unexplored niche in animal modeling of epilepsy despite the sensitivity of affiliative behaviors to emotionality and stress, which are known seizure triggers. Thus, the present studies examined the social phenotype of seizure-susceptible El and nonsusceptible ddY strains both in untreated animals and following preexposure to a handling stressor. The second aim of the present studies was to evaluate the dependence of sociability in El mice on the proconvulsive, stress neuropeptide corticotropin-releasing factor (CRF) using CRF-SAP, a conjugate of CRF and the toxin saporin, which selectively reduced CRF peptide levels in the basolateral amygdala of El mice. El mice exhibited lower social investigation times than ddY counterparts, whereas central administration of CRF-SAP normalized social investigation times relative to ddY controls. Moreover, handling-induced seizures in El mice were reduced by 50% following treatment with CRF-SAP relative to saporin alone-injected El controls. The results of this study suggest that tonically activated CRF systems in the El mouse brain suppress affiliative behavior and facilitate evoked seizures.

  12. Neural Processing of Calories in Brain Reward Areas Can be Modulated by Reward Sensitivity.

    Science.gov (United States)

    van Rijn, Inge; Griffioen-Roose, Sanne; de Graaf, Cees; Smeets, Paul A M

    2015-01-01

    A food's reward value is dependent on its caloric content. Furthermore, a food's acute reward value also depends on hunger state. The drive to obtain rewards (reward sensitivity), however, differs between individuals. Here, we assessed the association between brain responses to calories in the mouth and trait reward sensitivity in different hunger states. Firstly, we assessed this in data from a functional neuroimaging study (van Rijn et al., 2015), in which participants (n = 30) tasted simple solutions of a non-caloric sweetener with or without a non-sweet carbohydrate (maltodextrin) during hunger and satiety. Secondly, we expanded these analyses to regular drinks by assessing the same relationship in data from a study in which soft drinks sweetened with either sucrose or a non-caloric sweetener were administered during hunger (n = 18) (Griffioen-Roose et al., 2013). First, taste activation by the non-caloric solution/soft drink was subtracted from that by the caloric solution/soft drink to eliminate sweetness effects and retain activation induced by calories. Subsequently, this difference in taste activation was correlated with reward sensitivity as measured with the BAS drive subscale of the Behavioral Activation System (BAS) questionnaire. When participants were hungry and tasted calories from the simple solution, brain activation in the right ventral striatum (caudate), right amygdala and anterior cingulate cortex (bilaterally) correlated negatively with BAS drive scores. In contrast, when participants were satiated, taste responses correlated positively with BAS drive scores in the left caudate. These results were not replicated for soft drinks. Thus, neural responses to oral calories from maltodextrin were modulated by reward sensitivity in reward-related brain areas. This was not the case for sucrose. This may be due to the direct detection of maltodextrin, but not sucrose in the oral cavity. Also, in a familiar beverage, detection of calories per se may be

  13. Neural processing of calories in brain reward areas can be modulated by reward sensitivity

    Directory of Open Access Journals (Sweden)

    Inge eVan Rijn

    2016-01-01

    Full Text Available A food’s reward value is dependent on its caloric content. Furthermore, a food’s acute reward value also depends on hunger state. The drive to obtain rewards (reward sensitivity, however, differs between individuals. Here, we assessed the association between brain responses to calories in the mouth and trait reward sensitivity in different hunger states. Firstly, we assessed this in data from a functional neuroimaging study (van Rijn et al., 2015, in which participants (n=30 tasted simple solutions of a non-caloric sweetener with or without a non-sweet carbohydrate (maltodextrin during hunger and satiety. Secondly, we expanded these analyses to regular drinks by assessing the same relationship in data from a study in which soft drinks sweetened with either sucrose or a non-caloric sweetener were administered during hunger (n=18 (Griffioen-Roose et al., 2013. First, taste activation by the non-caloric solution/soft drink was subtracted from that by the caloric solution/soft drink to eliminate sweetness effects and retain activation induced by calories. Subsequently, this difference in taste activation was correlated with reward sensitivity as measured with the BAS drive subscale of the Behavioral Activation System (BAS questionnaire.When participants were hungry and tasted calories from the simple solution, brain activation in the right ventral striatum (caudate, right amygdala and anterior cingulate cortex (bilaterally correlated negatively with BAS drive scores. In contrast, when participants were satiated, taste responses correlated positively with BAS drive scores in the left caudate. These results were not replicated for soft drinks. Thus, neural responses to oral calories from maltodextrin were modulated by reward sensitivity in reward-related brain areas. This was not the case for sucrose. This may be due to the direct detection of maltodextrin, but not sucrose in the oral cavity. Also, in a familiar beverage, detection of calories per

  14. Exenatide Regulates Cerebral Glucose Metabolism in Brain Areas Associated With Glucose Homeostasis and Reward System.

    Science.gov (United States)

    Daniele, Giuseppe; Iozzo, Patricia; Molina-Carrion, Marjorie; Lancaster, Jack; Ciociaro, Demetrio; Cersosimo, Eugenio; Tripathy, Devjit; Triplitt, Curtis; Fox, Peter; Musi, Nicolas; DeFronzo, Ralph; Gastaldelli, Amalia

    2015-10-01

    Glucagon-like peptide 1 receptors (GLP-1Rs) have been found in the brain, but whether GLP-1R agonists (GLP-1RAs) influence brain glucose metabolism is currently unknown. The study aim was to evaluate the effects of a single injection of the GLP-1RA exenatide on cerebral and peripheral glucose metabolism in response to a glucose load. In 15 male subjects with HbA1c of 5.7 ± 0.1%, fasting glucose of 114 ± 3 mg/dL, and 2-h glucose of 177 ± 11 mg/dL, exenatide (5 μg) or placebo was injected in double-blind, randomized fashion subcutaneously 30 min before an oral glucose tolerance test (OGTT). The cerebral glucose metabolic rate (CMRglu) was measured by positron emission tomography after an injection of [(18)F]2-fluoro-2-deoxy-d-glucose before the OGTT, and the rate of glucose absorption (RaO) and disposal was assessed using stable isotope tracers. Exenatide reduced RaO0-60 min (4.6 ± 1.4 vs. 13.1 ± 1.7 μmol/min ⋅ kg) and decreased the rise in mean glucose0-60 min (107 ± 6 vs. 138 ± 8 mg/dL) and insulin0-60 min (17.3 ± 3.1 vs. 24.7 ± 3.8 mU/L). Exenatide increased CMRglu in areas of the brain related to glucose homeostasis, appetite, and food reward, despite lower plasma insulin concentrations, but reduced glucose uptake in the hypothalamus. Decreased RaO0-60 min after exenatide was inversely correlated to CMRglu. In conclusion, these results demonstrate, for the first time in man, a major effect of a GLP-1RA on regulation of brain glucose metabolism in the absorptive state. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  15. Brain response to a humanoid robot in areas implicated in the perception of human emotional gestures.

    Science.gov (United States)

    Chaminade, Thierry; Zecca, Massimiliano; Blakemore, Sarah-Jayne; Takanishi, Atsuo; Frith, Chris D; Micera, Silvestro; Dario, Paolo; Rizzolatti, Giacomo; Gallese, Vittorio; Umiltà, Maria Alessandra

    2010-07-21

    The humanoid robot WE4-RII was designed to express human emotions in order to improve human-robot interaction. We can read the emotions depicted in its gestures, yet might utilize different neural processes than those used for reading the emotions in human agents. Here, fMRI was used to assess how brain areas activated by the perception of human basic emotions (facial expression of Anger, Joy, Disgust) and silent speech respond to a humanoid robot impersonating the same emotions, while participants were instructed to attend either to the emotion or to the motion depicted. Increased responses to robot compared to human stimuli in the occipital and posterior temporal cortices suggest additional visual processing when perceiving a mechanical anthropomorphic agent. In contrast, activity in cortical areas endowed with mirror properties, like left Broca's area for the perception of speech, and in the processing of emotions like the left anterior insula for the perception of disgust and the orbitofrontal cortex for the perception of anger, is reduced for robot stimuli, suggesting lesser resonance with the mechanical agent. Finally, instructions to explicitly attend to the emotion significantly increased response to robot, but not human facial expressions in the anterior part of the left inferior frontal gyrus, a neural marker of motor resonance. Motor resonance towards a humanoid robot, but not a human, display of facial emotion is increased when attention is directed towards judging emotions. Artificial agents can be used to assess how factors like anthropomorphism affect neural response to the perception of human actions.

  16. Semantic brain areas are involved in gesture comprehension: An electrical neuroimaging study.

    Science.gov (United States)

    Proverbio, Alice Mado; Gabaro, Veronica; Orlandi, Andrea; Zani, Alberto

    2015-08-01

    While the mechanism of sign language comprehension in deaf people has been widely investigated, little is known about the neural underpinnings of spontaneous gesture comprehension in healthy speakers. Bioelectrical responses to 800 pictures of actors showing common Italian gestures (e.g., emblems, deictic or iconic gestures) were recorded in 14 persons. Stimuli were selected from a wider corpus of 1122 gestures. Half of the pictures were preceded by an incongruent description. ERPs were recorded from 128 sites while participants decided whether the stimulus was congruent. Congruent pictures elicited a posterior P300 followed by late positivity, while incongruent gestures elicited an anterior N400 response. N400 generators were investigated with swLORETA reconstruction. Processing of congruent gestures activated face- and body-related visual areas (e.g., BA19, BA37, BA22), the left angular gyrus, mirror fronto/parietal areas. The incongruent-congruent contrast particularly stimulated linguistic and semantic brain areas, such as the left medial and the superior temporal lobe. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Ventral medullary neurones excited from the hypothalamic and mid-brain defence areas.

    Science.gov (United States)

    Hilton, S M; Smith, P R

    1984-07-01

    In cats anaesthetised with chloralose, the ventral medulla was explored in and around the strip previously identified as the location of the efferent pathway from the hypothalamic and mid-brain defence areas to the spinal cord, in a search for neurones excited by electrical stimulation of the defence areas. Such units were found mostly in the caudal part of this strip, at a depth of not more than 500 microns from the surface. Nearly all were located in the ventral part of nucleus paragigantocellularis lateralis (PGL) at the level of the rostral pole of the inferior olive. There was evidence of temporal and spatial facilitation, indicating a convergent excitatory input from the defence areas onto neurones in PGL. This is consistent with earlier evidence of a synaptic relay in the efferent pathway at this site. When the pathway is blocked at this site, arterial blood pressure falls profoundly, so activity in these neurones may be essential for the normal level of sympathetic nerve activity.

  18. Synaesthetic Colour in the Brain: Beyond Colour Areas. A Functional Magnetic Resonance Imaging Study of Synaesthetes and Matched Controls

    OpenAIRE

    van Leeuwen, Tessa M.; Petersson, Karl Magnus; Hagoort, Peter

    2010-01-01

    Background In synaesthesia, sensations in a particular modality cause additional experiences in a second, unstimulated modality (e.g., letters elicit colour). Understanding how synaesthesia is mediated in the brain can help to understand normal processes of perceptual awareness and multisensory integration. In several neuroimaging studies, enhanced brain activity for grapheme-colour synaesthesia has been found in ventral-occipital areas that are also involved in real colour processing. Our q...

  19. SCARB1 rs5888 is associated with the risk of age-related macular degeneration susceptibility and an impaired macular area.

    Science.gov (United States)

    Stanislovaitiene, Daiva; Zaliuniene, Dalia; Krisciukaitis, Algimantas; Petrolis, Robertas; Smalinskiene, Alina; Lesauskaite, Vita; Tamosiunas, Abdonas; Lesauskaite, Vaiva

    2017-01-01

    Age-related macular degeneration (ARMD), a progressive retinal disease, is responsible for an impaired central vision in about 180 million people worldwide. Current options for ARMD prevention and treatment are limited due to an incomplete understanding of disease etiopathogenesis. We aimed to test the hypothesis that the single nucleotide polymorphism rs5888 of SCARB1 gene reflecting lipid and antioxidant micronutrient metabolism pathways is associated with ARMD susceptibility and to evaluate if there is any relation between SCARB1 rs5888 and the macular lesion area. The prospective case-control study included patients with ARMD (n = 215) and the reference group (n = 238) drawn from a random sample of the Lithuanian population (n = 1436). The genotyping test of SCARB1 rs5888 was carried out using the real-time polymerase chain reaction method. Regression analysis adjusted by gender and age demonstrated that SCARB1 rs5888 TT genotype significantly decreased the odds for ARMD development (OR: 0.61, 95%; CI: 0.380-0.981, p = 0.04). A smoking habit and leading an outdoor life are associated with larger macular lesion areas in ARMD patients (0.54 (0.00-39.06) vs. 3.09 (0.02-19.30) and 0.27 (0.00-34.57) vs. 0.75 (0.00-39.06), respectively). In late stage ARMD subjects with CT genotype, the macular lesion area was larger than in TT carriers (7.64 (0.49-39.06) mm 2 vs. 5.02 (0.03-37.06) mm 2 , p = 0.006). SCARB1 rs5888 and environmental oxidative stress have a prominent role in ARMD susceptibility, early ARMD progression to advanced stage disease and even in the outcome of the disease-an area of macular lesion.

  20. Biogenic amines in brain areas of rats and response to varying dose levels of whole body gamma irradiation

    International Nuclear Information System (INIS)

    Abdelhamid, F.M.; Elmossalamy, N.; Othman, S.A.; Roushdy, H.M.; Abdelraheem, K.

    1994-01-01

    The levels of norepinephrine (NE), dopamine (DA), 5-hydroxy-tryptamine (5-HT) and 5-hydroxy-indole acetic acid (5-HIAA) were examined in the brain areas:cortex,: cerebellum, striatum and pons in rats exposed to whole body gamma-irradiation at the dose levels 6.5 and 10 Gy. The data obtained indicated that: 6.5 Gy induced in all brain areas, a slight increase in 5-HT concomitant with significant decrease in NE, DA levels, besides a significant increase in 5-HTAA in cerebellum and pons. After the dose 10 Gy the maximum excitation of 5-HT level was in striatum whereas declines in NE, DA were recorded in all brain areas. 5-HIAA displayed significant increase in cerebellum and pons and maximum decline in the cortex. 4 tab

  1. Daily Dose effect of Valerian root extract on some Neurotransmitter contents in different Brain areas of male Albino Rats

    International Nuclear Information System (INIS)

    Waggas, Abeer M

    2007-01-01

    The aim of the present study was to investigate the daily effect of valerian (Valeriana officinalis L .) root extract on epinephrine (E), norepinephrine (NE), dopamine (DA), serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) , and gamma-aminobutyric acid (GABA) contents in different brain areas (cerebellum , pons plus medulla oblongata , striatum , cerebral cortex, hypothalamus, midbrain and hippocampus) of male albino rats .The daily intraperitoneal ( i.p.) injection of 300 mg/kg body wt valerian for 30 days caused a significant increase in epinephrine ( E ) content in pons plus medulla oblongata, cerebral cortex , hypothalamus and in midbrain . Norepinephrine (NE ) content was significantly increased in all brain areas tested except in cerebellum and cerebral cortex . Dopamine (DA) content was significantly increased in all tested brain areas except in cerebral cortex and hippocampus . moreover , there was also a significant increase in serotonin (5-HT ) and 5-hydroxyindol acetic acid (5-HIAA) contents in all tested brain areas . However, gamma-aminobutyric acid (GABA) content was significantly decreased in all tested brain areas . After the extract withdrawal, the increase in ( E, NE, DA , 5-HT ) contents and the decrease in GABA content persisted in pons plus medulla oblongata , striatum , midbrain and hippocampus , and this might be due to regional differences toward the effect. The increase in E, NE, DA , 5-HT and 5-HIAA contents, at the same time the decrease in GABA content in the different brain areas of albino rats may be due to the presence of both valepotriates and valerenic acid in the extract which mediated the GABA ergic mechanisms including the inhibition of GABA metabolism and the increase in GABA synthesis and release , although agonized the GABAA receptors which led to the inhibit of the neurotransmitter release. Valerian root extract may be useful as a herbal medicine having sedative effect and it is safe. (author)

  2. Abnormal functional lateralization and activity of language brain areas in typical specific language impairment (developmental dysphasia)

    Science.gov (United States)

    De Guibert, Clément; Maumet, Camille; Jannin, Pierre; Ferré, Jean-Christophe; Tréguier, Catherine; Barillot, Christian; Le Rumeur, Elisabeth; Allaire, Catherine; Biraben, Arnaud

    2011-01-01

    Atypical functional lateralization and specialization for language have been proposed to account for developmental language disorders, yet results from functional neuroimaging studies are sparse and inconsistent. This functional magnetic resonance imaging study compared children with a specific subtype of specific language impairment affecting structural language (n=21), to a matched group of typically-developing children using a panel of four language tasks neither requiring reading nor metalinguistic skills, including two auditory lexico-semantic tasks (category fluency and responsive naming) and two visual phonological tasks based on picture naming. Data processing involved normalizing the data with respect to a matched pairs pediatric template, groups and between-groups analysis, and laterality indexes assessment within regions of interest using single and combined task analysis. Children with specific language impairment exhibited a significant lack of left lateralization in all core language regions (inferior frontal gyrus-opercularis, inferior frontal gyrus-triangularis, supramarginal gyrus, superior temporal gyrus), across single or combined task analysis, but no difference of lateralization for the rest of the brain. Between-group comparisons revealed a left hypoactivation of Wernicke’s area at the posterior superior temporal/supramarginal junction during the responsive naming task, and a right hyperactivation encompassing the anterior insula with adjacent inferior frontal gyrus and the head of the caudate nucleus during the first phonological task. This study thus provides evidence that this specific subtype of specific language impairment is associated with atypical lateralization and functioning of core language areas. PMID:21719430

  3. Early auditory processing in area V5/MT+ of the congenitally blind brain.

    Science.gov (United States)

    Watkins, Kate E; Shakespeare, Timothy J; O'Donoghue, M Clare; Alexander, Iona; Ragge, Nicola; Cowey, Alan; Bridge, Holly

    2013-11-13

    Previous imaging studies of congenital blindness have studied individuals with heterogeneous causes of blindness, which may influence the nature and extent of cross-modal plasticity. Here, we scanned a homogeneous group of blind people with bilateral congenital anophthalmia, a condition in which both eyes fail to develop, and, as a result, the visual pathway is not stimulated by either light or retinal waves. This model of congenital blindness presents an opportunity to investigate the effects of very early visual deafferentation on the functional organization of the brain. In anophthalmic animals, the occipital cortex receives direct subcortical auditory input. We hypothesized that this pattern of subcortical reorganization ought to result in a topographic mapping of auditory frequency information in the occipital cortex of anophthalmic people. Using functional MRI, we examined auditory-evoked activity to pure tones of high, medium, and low frequencies. Activity in the superior temporal cortex was significantly reduced in anophthalmic compared with sighted participants. In the occipital cortex, a region corresponding to the cytoarchitectural area V5/MT+ was activated in the anophthalmic participants but not in sighted controls. Whereas previous studies in the blind indicate that this cortical area is activated to auditory motion, our data show it is also active for trains of pure tone stimuli and in some anophthalmic participants shows a topographic mapping (tonotopy). Therefore, this region appears to be performing early sensory processing, possibly served by direct subcortical input from the pulvinar to V5/MT+.

  4. Foundation Considerations in Siting of Nuclear Facilities in Karst Terrains and Other Areas Susceptible to Ground Collapse.

    Science.gov (United States)

    1981-05-01

    eff on goun- an sufac-watr lvels Th reultsof hesecliati to solution due to surface infiltration, whereas similar rocks in tropi- cal areas may exhibit...only tools to ensure against mistakes in logic (Baecher, 1978). Most of the mathematical models for detection are in the general category of geometric...any other target. With these assumptions, the number of targets can be modeled mathematically with the Poisson distribution. This has been done by

  5. Review article "Remarks on factors influencing shear wave velocities and their role in evaluating susceptibilities to earthquake-triggered slope instability: case study for the Campania area (Italy"

    Directory of Open Access Journals (Sweden)

    V. Paoletti

    2012-07-01

    Full Text Available Shear wave velocities have a fundamental role in connection with the mitigation of seismic hazards, as their low values are the main causes of site amplification phenomena and can significantly influence the susceptibility of a territory to seismic-induced landslides. The shear wave velocity (Vs and modulus (G of each lithological unit are influenced by factors such as the degree of fracturing and faulting, the porosity, the clay amount and the precipitation, with the latter two influencing the unit water content. In this paper we discuss how these factors can affect the Vs values and report the results of different analyses that quantify the reduction in the rock Vs and shear modulus values connected to the presence of clay and water. We also show that significant results in assessing seismic-induced slope failure susceptibility for land planning targets could be achieved through a careful evaluation, based only on literature studies, of the geo-lithological and geo-seismic features of the study area.

  6. [Measurement of the blood flow in various areas of the rat brain by means of microspheres].

    Science.gov (United States)

    Deroo, J; Gerber, G B

    1976-01-01

    A method is described to measure regional blood flow in different structures of the rat brain. Microspheres (15 micron) are injected, the brain is sectioned, stained for myeline, radioautographs are prepared and the microspheres in the different structures are counted. The values obtained for different brain structures are counted. The values obtained for different brain regions (cortex, corpus callosum, thalamus hipocampus, hypothalamic region, colliculi, cerebellum, pons, medulla) compare well with those published by others on larger animals. In rats fed 1% of lead from birth, higher blood flow is found in the cortex and a lower one in the interior part of the brain compared to controls.

  7. Opposite modulation of brain stimulation reward by NMDA and AMPA receptors in the ventral tegmental area.

    Science.gov (United States)

    Ducrot, Charles; Fortier, Emmanuel; Bouchard, Claude; Rompré, Pierre-Paul

    2013-01-01

    Previous studies have shown that blockade of ventral tegmental area (VTA) glutamate N-Methyl-D-Aspartate (NMDA) receptors induces reward, stimulates forward locomotion and enhances brain stimulation reward. Glutamate induces two types of excitatory response on VTA neurons, a fast and short lasting depolarization mediated by α-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptors and a longer lasting depolarization mediated by NMDA receptors. A role for the two glutamate receptors in modulation of VTA neuronal activity is evidenced by the functional change in AMPA and NMDA synaptic responses that result from repeated exposure to reward. Since both receptors contribute to the action of glutamate on VTA neuronal activity, we studied the effects of VTA AMPA and NMDA receptor blockade on reward induced by electrical brain stimulation. Experiments were performed on rats trained to self-administer electrical pulses in the medial posterior mesencephalon. Reward thresholds were measured with the curve-shift paradigm before and for 2 h after bilateral VTA microinjections of the AMPA antagonist, NBQX (2,3,-Dioxo-6-nitro-1,2,3,4-tetrahydrobenzo(f)quinoxaline-7-sulfonamide, 0, 80, and 800 pmol/0.5 μl/side) and of a single dose (0.825 nmol/0.5 μl/side) of the NMDA antagonist, PPPA (2R,4S)-4-(3-Phosphonopropyl)-2-piperidinecarboxylic acid). NBQX produced a dose-dependent increase in reward threshold with no significant change in maximum rate of responding. Whereas PPPA injected at the same VTA sites produced a significant time dependent decrease in reward threshold and increase in maximum rate of responding. We found a negative correlation between the magnitude of the attenuation effect of NBQX and the enhancement effect of PPPA; moreover, NBQX and PPPA were most effective when injected, respectively, into the anterior and posterior VTA. These results suggest that glutamate acts on different receptor sub-types, most likely located on different VTA neurons, to

  8. Clinical Evaluation of Brain Perfusion SPECT with Brodmann Areas Mapping in Early Diagnosis of Alzheimer's Disease.

    Science.gov (United States)

    Valotassiou, Varvara; Papatriantafyllou, John; Sifakis, Nikolaos; Tzavara, Chara; Tsougos, Ioannis; Psimadas, Dimitrios; Fezoulidis, Ioannis; Kapsalaki, Eftychia; Hadjigeorgiou, George; Georgoulias, Panagiotis

    2015-01-01

    Early diagnosis of Alzheimer's disease (AD) based on clinical criteria alone may be problematic, while current and future treatments should be administered earlier in order to be more effective. Thus, various disease biomarkers could be used for early detection of AD. We evaluated brain perfusion with 99mTc-HMPAO single photon emission computed tomography (SPECT) and Brodmann areas (BAs) mapping in mild AD using an automated software (NeuroGam) for the semi-quantitative evaluation of perfusion in BAs and the comparison with the software's normal database. We studied 34 consecutive patients with mild AD: 9 men, 25 women, mean age 70.9 ± 8.1 years, mean Mini-Mental State Examination 22.6 ± 2.5. BAs 25L, 25R, 38L, 38R, 28L, 28R, 36L, and 36R had the lower mean perfusion values, while BAs 31L, 31R, 19R, 18L, 18R, 17L, and 17R had the higher mean values. Compared with healthy subjects of the same age, perfusion values in BAs 25L, 25R, 28R, 28L, 36L, and 36R had the greatest deviations from the healthy sample, while the lowest deviations were found in BAs 32L, 32R, 19R, 24L, 17L, 17R, 18L, and 18R. A percentage of ≥94% of patients had perfusion values more than -2SDs below the mean of healthy subjects in BAs 38R, 38L, 36L, 36R, 23L, 23R, 22L, 44L, 28L, 28R, 25L, and 25R. The corresponding proportion was less than 38% for BAs 11L, 19R, 32L, 32R, 18L, 18R, 24L, and 17R. In conclusion, brain SPECT studies with automated perfusion mapping could be useful as an ancillary tool in daily practice, revealing perfusion impairments in early AD.

  9. Brain response to a humanoid robot in areas implicated in the perception of human emotional gestures.

    Directory of Open Access Journals (Sweden)

    Thierry Chaminade

    2010-07-01

    Full Text Available The humanoid robot WE4-RII was designed to express human emotions in order to improve human-robot interaction. We can read the emotions depicted in its gestures, yet might utilize different neural processes than those used for reading the emotions in human agents.Here, fMRI was used to assess how brain areas activated by the perception of human basic emotions (facial expression of Anger, Joy, Disgust and silent speech respond to a humanoid robot impersonating the same emotions, while participants were instructed to attend either to the emotion or to the motion depicted.Increased responses to robot compared to human stimuli in the occipital and posterior temporal cortices suggest additional visual processing when perceiving a mechanical anthropomorphic agent. In contrast, activity in cortical areas endowed with mirror properties, like left Broca's area for the perception of speech, and in the processing of emotions like the left anterior insula for the perception of disgust and the orbitofrontal cortex for the perception of anger, is reduced for robot stimuli, suggesting lesser resonance with the mechanical agent. Finally, instructions to explicitly attend to the emotion significantly increased response to robot, but not human facial expressions in the anterior part of the left inferior frontal gyrus, a neural marker of motor resonance.Motor resonance towards a humanoid robot, but not a human, display of facial emotion is increased when attention is directed towards judging emotions.Artificial agents can be used to assess how factors like anthropomorphism affect neural response to the perception of human actions.

  10. Functional and morphological effects of diazepam and midazolam on tumor vasculature in the 9L gliosarcoma brain tumor model using dynamic susceptibility contrast MRI: a comparative study

    Directory of Open Access Journals (Sweden)

    Yan N

    2017-10-01

    Full Text Available Nuo Yan,1 Yuzhen Zheng,2 Cheng Yang1 1Second Department of Anesthesiology, The Affiliated Hospital to Logistics University of PAP, Tianjin, 2Department of Anesthesiology, Tianjin Huanhu Hospital, Tianjin, China Abstract: Antiangiogenic therapy attenuates tumor growth by reducing vascularization. Diazepam (DZP and midazolam (MZL have antiangiogenic properties in human umbilical vein endothelial cells. Thus, we investigated the antiangiogenic activity of DZP and MZL in the rat 9L gliosarcoma brain tumor model. The effect on tumor vasculature was evaluated using dynamic susceptibility contrast magnetic resonance imaging with gradient-echo (GE and spin-echo (SE to assess perfusion parameters, including cerebral blood volume (CBV, cerebral blood flow (CBF, mean transit time (MTT, and mean vessel diameter. The GE-normalized CBF (nCBF in the tumors of untreated controls was significantly lower than that in normal brain tissue, whereas the CBV and MTT were higher. DZP- and MZL-treated rats had higher CBF and lower CBV and MTT values than did untreated controls. The tumor size decreased significantly to 33.5% in DZP-treated rats (P<0.001 and 22.5% in MZL-treated rats (P<0.01 relative to controls. The SE-normalized CBV was lower in DZP-treated (32.9% and MZL-treated (10.6% rats compared with controls. The mean vessel diameter decreased significantly by 32.5% in DPZ-treated and by 24.9% in MZL-treated rats compared with controls (P<0.01. The GE and SE nCBF values were higher in DZP-treated (49.9% and 40.1%, respectively and MZL-treated (41.2% and 32.1%, respectively rats than in controls. The GE- and SE-normalized MTTs were lower in DZP-treated (48.2% and 59.8%, respectively and MZL-treated (40.5% and 51.2%, respectively rats than in controls. Both DZP and MZL had antiangiogenic effects on tumor perfusion and vasculature; however, the antiangiogenic activity of DZP is more promising than that of MZL. Keywords: diazepam, midazolam, 9L gliosarcoma

  11. Comparative study of activities in reactive oxygen species production/defense system in mitochondria of rat brain and liver, and their susceptibility to methylmercury toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Mori, N.; Hirayama, K. [Kumamoto University, School of Health Science, Kumamoto (Japan); Yasutake, A. [National Institute for Minamata Disease, Minamata (Japan)

    2007-11-15

    The involvement of oxidative stress has been suggested as a mechanism for neurotoxicity caused by methylmercury (MeHg), but the mechanism for MeHg selective toxicity in the central nervous system is still unclear. In this research, to clarify the mechanism of selective neurotoxicity caused by MeHg, the oxygen consumption levels, the reactive oxygen species (ROS) production rates and several antioxidant levels in mitochondria were compared among the cerebrum, cerebellum and liver of male Wistar rats. In addition, the alterations of these indexes were examined in MeHg-intoxicated rats (oral administration of 10 mg/kg day, for 5 days). Although the cerebrum and cerebellum in intact rats showed higher mitochondrial oxygen consumption levels and ROS production rates than the liver, glutathione peroxidase (GPX) and superoxide dismutase (SOD) activities were much lower in the cerebrum and cerebellum than in the liver. Especially, the cerebellum showed the highest oxygen consumption and ROS production rate and the lowest mitochondrial glutathione (GSH) levels among the tissues examined. In the MeHg-treated rats, decrease in the oxygen consumption and increase in the ROS generation were found only in the cerebellum mitochondria, despite a lower Hg accumulation in the mitochondrial fraction compared to the liver. Since MeHg treatment produced an enhancement of ROS generation in cerebellum mitochondria supplemented with succinate substrates, MeHg-induced oxidative stress might affect the complex II-III mediated pathway in the electron transfer chain in the cerebellum mitochondria. Our study suggested that inborn factors, high production system activity and low defense system activity of ROS in the brain, would relate to the high susceptibility of the central nervous system to MeHg toxicity. (orig.)

  12. Prolonged Repeated Acupuncture Stimulation Induces Habituation Effects in Pain-Related Brain Areas: An fMRI Study

    Science.gov (United States)

    Li, Chuanfu; Yang, Jun; Park, Kyungmo; Wu, Hongli; Hu, Sheng; Zhang, Wei; Bu, Junjie; Xu, Chunsheng; Qiu, Bensheng; Zhang, Xiaochu

    2014-01-01

    Most previous studies of brain responses to acupuncture were designed to investigate the acupuncture instant effect while the cumulative effect that should be more important in clinical practice has seldom been discussed. In this study, the neural basis of the acupuncture cumulative effect was analyzed. For this experiment, forty healthy volunteers were recruited, in which more than 40 minutes of repeated acupuncture stimulation was implemented at acupoint Zhusanli (ST36). Three runs of acupuncture fMRI datasets were acquired, with each run consisting of two blocks of acupuncture stimulation. Besides general linear model (GLM) analysis, the cumulative effects of acupuncture were analyzed with analysis of covariance (ANCOVA) to find the association between the brain response and the cumulative duration of acupuncture stimulation in each stimulation block. The experimental results showed that the brain response in the initial stage was the strongest although the brain response to acupuncture was time-variant. In particular, the brain areas that were activated in the first block and the brain areas that demonstrated cumulative effects in the course of repeated acupuncture stimulation overlapped in the pain-related areas, including the bilateral middle cingulate cortex, the bilateral paracentral lobule, the SII, and the right thalamus. Furthermore, the cumulative effects demonstrated bimodal characteristics, i.e. the brain response was positive at the beginning, and became negative at the end. It was suggested that the cumulative effect of repeated acupuncture stimulation was consistent with the characteristic of habituation effects. This finding may explain the neurophysiologic mechanism underlying acupuncture analgesia. PMID:24821143

  13. Diagnostic work up for language testing in patients undergoing awake craniotomy for brain lesions in language areas.

    Science.gov (United States)

    Bilotta, Federico; Stazi, Elisabetta; Titi, Luca; Lalli, Diana; Delfini, Roberto; Santoro, Antonio; Rosa, Giovanni

    2014-06-01

    Awake craniotomy is the technique of choice in patients with brain tumours adjacent to primary and accessory language areas (Broca's and Wernicke's areas). Language testing should be aimed to detect preoperative deficits, to promptly identify the occurrence of new intraoperative impairments and to establish the course of postoperative language status. Aim of this case series is to describe our experience with a dedicated language testing work up to evaluate patients with or at risk for language disturbances undergoing awake craniotomy for brain tumour resection. Pre- and intra operative testing was accomplished with 8 tests. Intraoperative evaluation was accomplished when patients were fully cooperative (Ramsey awake craniotomy for brain tumour resection with preoperative language disturbances or at risk for postoperative language deficits. This approach allows a systematic evaluation and recording of language function status and can be accomplished even when a neuropsychologist or speech therapist are not involved in the operation crew.

  14. Linguistic processing in visual and modality-nonspecific brain areas: PET recordings during selective attention.

    Science.gov (United States)

    Vorobyev, Victor A; Alho, Kimmo; Medvedev, Svyatoslav V; Pakhomov, Sergey V; Roudas, Marina S; Rutkovskaya, Julia M; Tervaniemi, Mari; Van Zuijen, Titia L; Näätänen, Risto

    2004-07-01

    Positron emission tomography (PET) was used to investigate the neural basis of selective processing of linguistic material during concurrent presentation of multiple stimulus streams ("cocktail-party effect"). Fifteen healthy right-handed adult males were to attend to one of three simultaneously presented messages: one presented visually, one to the left ear, and one to the right ear. During the control condition, subjects attended to visually presented consonant letter strings and ignored auditory messages. This paper reports the modality-nonspecific language processing and visual word-form processing, whereas the auditory attention effects have been reported elsewhere [Cogn. Brain Res. 17 (2003) 201]. The left-hemisphere areas activated by both the selective processing of text and speech were as follows: the inferior prefrontal (Brodmann's area, BA 45, 47), anterior temporal (BA 38), posterior insular (BA 13), inferior (BA 20) and middle temporal (BA 21), occipital (BA 18/30) cortices, the caudate nucleus, and the amygdala. In addition, bilateral activations were observed in the medial occipito-temporal cortex and the cerebellum. Decreases of activation during both text and speech processing were found in the parietal (BA 7, 40), frontal (BA 6, 8, 44) and occipito-temporal (BA 37) regions of the right hemisphere. Furthermore, the present data suggest that the left occipito-temporal cortex (BA 18, 20, 37, 21) can be subdivided into three functionally distinct regions in the posterior-anterior direction on the basis of their activation during attentive processing of sublexical orthography, visual word form, and supramodal higher-level aspects of language.

  15. Neuropsychological significance of areas of high signal intensity on brain MRIs of children with neurofibromatosis.

    Science.gov (United States)

    Moore, B D; Slopis, J M; Schomer, D; Jackson, E F; Levy, B M

    1996-06-01

    Of children with neurofibromatosis (NF), 40% have a cognitive or learning impairment. Approximately 60% also have anomalous areas of high signal intensity on T2-weighted brain MRIs. The association of these hyperintensities and neuropsychological status is not fully understood. We administered a battery of neuropsychological tests and a standard clinical MRI to determine the impact of hyperintensity presence, number, and location on cognitive status in 84 children (8 to 16 years) with NF type 1. These children underwent standard clinical MRI using a GE 1.5-tesla scanner (except one child who was examined with a 1.0-tesla scanner). We conducted three types of analyses: Hyperintensity presence or absence.-Scores of children with (55%) and without hyperintensities (45%) were compared using t tests. No statistically significant differences between groups in intellectual functioning or any neuropsychological variable were found. Number of hyperintensities-The number of hyperintensity locations per child ranged from one to five (mean = 2.22). Pearson correlations revealed no significant association between the number of hyperintensities and neuropsychological performance. Location of hyperintensities-In four of the five locations studied, no statistically significant differences were found between scores of children with a hyperintensity in an area and those with one elsewhere. However, mean scores for IQ, Memory, Motor, Distractibility, and Attention domains for children with hyperintensities in the thalamus were significantly lower than scores for those with hyperintensities elsewhere. These results suggest that the simple presence or absence of hyperintensities, or their total number, is not as important as their anatomic location for detecting their relationship with neuropsychological status. Taking location into account, hyperintensities in the cerebral hemispheres, basal ganglia, brainstem, or cerebellum seem to have no impact on neuropsychological functioning

  16. HTLV-I associated myelopathy with multiple spotty areas in cerebral white matter and brain stem by MRI

    Energy Technology Data Exchange (ETDEWEB)

    Hara, Yasuo; Takahashi, Mitsuo; Yoshikawa, Hiroo; Yorifuji, Shirou; Tarui, Seiichiro

    1988-01-01

    A 48-year-old woman was admitted with complaints of urinary incontinence and gait disturbance, both of which had progressed slowly without any sign of remission. Family history was not contributory. Neurologically, extreme spasticity was recoginized in the lower limbs. Babinski sign was positive bilaterally. Flower-like atypical lymphocytes were seen in blood. Positive anti-HTLV-I antibody was confirmed in serum and spinal fluid by western blot. She was diagnosed as having HTLV-I associated myelopathy (HAM). CT reveald calcification in bilateral globus pallidus, and MRI revealed multiple spotty areas in cerebral white matter and brain stem, but no spinal cord lesion was detectable. Electrophysiologically, brain stem auditory evoked potential (BAEP) suggested the presence of bilateral brain stem lesions. Neither median nor posterior tibial nerve somatosensory evoked potentials were evoked, a finding suggesting the existence of spinal cord lesion. In this case, the lesion was not confined to spinal cord, it was also observed in brain stem and cerebral white matter. Such distinct lesions in cerebral white matter and brain stem have not been reported in patients with HAM. It is suggested that HTLV-I is probably associated with cerebral white matter and brain stem.

  17. Specificities of Awake Craniotomy and Brain Mapping in Children for Resection of Supratentorial Tumors in the Language Area.

    Science.gov (United States)

    Delion, Matthieu; Terminassian, Aram; Lehousse, Thierry; Aubin, Ghislaine; Malka, Jean; N'Guyen, Sylvie; Mercier, Philippe; Menei, Philippe

    2015-12-01

    In the pediatric population, awake craniotomy began to be used for the resection of brain tumor located close to eloquent areas. Some specificities must be taken into account to adapt this method to children. The aim of this clinical study is to not only confirm the feasibility of awake craniotomy and language brain mapping in the pediatric population but also identify the specificities and necessary adaptations of the procedure. Six children aged 11 to 16 were operated on while awake under local anesthesia with language brain mapping for supratentorial brain lesions (tumor and cavernoma). The preoperative planning comprised functional magnetic resonance imaging (MRI) and neuropsychologic and psychologic assessment. The specific preoperative preparation is clearly explained including hypnosis conditioning and psychiatric evaluation. The success of the procedure was based on the ability to perform the language brain mapping and the tumor removal without putting the patient to sleep. We investigated the pediatric specificities, psychological experience, and neuropsychologic follow-up. The children experienced little anxiety, probably in large part due to the use of hypnosis. We succeeded in doing the cortical-subcortical mapping and removing the tumor without putting the patient to sleep in all cases. The psychological experience was good, and the neuropsychologic follow-up showed a favorable evolution. Preoperative preparation and hypnosis in children seemed important for performing awake craniotomy and contributing language brain mapping with the best possible psychological experience. The pediatrics specificities are discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Single-station seismic noise measures, microgravity, and 3D electrical tomographies to assess the sinkhole susceptibility: the "Il Piano" area (Elba Island - Italy) case study

    Science.gov (United States)

    Pazzi, Veronica; Di Filippo, Michele; Di Nezza, Maria; Carlà, Tommaso; Bardi, Federica; Marini, Federico; Fontanelli, Katia; Intrieri, Emanuele; Fanti, Riccardo

    2017-04-01

    Sudden subsurface collapse, cavities, and surface depressions, regardless of shape and origin, as well as doline are currently indicate by means of the term "sinkhole". This phenomenon can be classified according to a large variety of different schemes, depending on the dominant formation processes (soluble rocks karstic processes, acidic groundwater circulation, anthropogenic caves, bedrock poor geomechanical properties), and on the geological scenario behind the development of the phenomenon. Considering that generally sinkholes are densely clustered in "sinkhole prone areas", detection, forecasting, early warning, and effective monitoring are key aspects in sinkhole susceptibility assessment and risk mitigation. Nevertheless, techniques developed specifically for sinkhole detection, forecasting and monitoring are missing, probably because of a general lack of sinkhole risk awareness, and an intrinsic difficulties involved in detecting precursory sinkhole deformations before collapse. In this framework, integration of different indirect/non-invasive geophysical methods is the best practice approach. In this paper we present the results of an integrated geophysical survey at "Il Piano" (Elba Island - Italy), where at least nine sinkholes occurred between 2008 and 2014. 120 single-station seismic noise measures, 17 3D electrical tomographies (min area 140.3 m2, max area 10,188.9 m2; min electrode spacing 2 m, max electrode spacing 5 m), 964 measurement of microgravity spaced in a grid of 6 m to 8 m were carried out at the study area. The most likely origin for these sinkholes was considered related to sediment net erosion from the alluvium, caused by downward water circulation between aquifers. Therefore, the goals of the study were: i) obtaining a suitable geological and hydrogeological model of the area; ii) detecting possible cavities which could evolve in sinkholes, and finally iii) assess the sinkhole susceptibility of the area. Among the results of the

  19. Automated Multi-Contrast Brain Pathological Area Extraction from 2D MR Images

    Czech Academy of Sciences Publication Activity Database

    Dvořák, Pavel; Bartušek, Karel; Kropatsch, W.G.; Smékal, Z.

    2015-01-01

    Roč. 13, č. 1 (2015), s. 58-69 ISSN 1665-6423 R&D Projects: GA ČR GAP102/12/1104 Institutional support: RVO:68081731 Keywords : Brain Pathology * Brain Tumor * MRI * Multi-contrast MRI * Symmetry Analysis Subject RIV: BH - Optics, Masers, Lasers Impact factor: 0.447, year: 2013

  20. Shared susceptibility loci at 2q33 region for lung and esophageal cancers in high-incidence areas of esophageal cancer in northern China.

    Directory of Open Access Journals (Sweden)

    Xue Ke Zhao

    Full Text Available Cancers from lung and esophagus are the leading causes of cancer-related deaths in China and share many similarities in terms of histological type, risk factors and genetic variants. Recent genome-wide association studies (GWAS in Chinese esophageal cancer patients have demonstrated six high-risk candidate single nucleotide polymorphisms (SNPs. Thus, the present study aimed to determine the risk of these SNPs predisposing to lung cancer in Chinese population.A total of 1170 lung cancer patients and 1530 normal subjects were enrolled in this study from high-incidence areas for esophageal cancer in Henan, northern China. Five milliliters of blood were collected from all subjects for genotyping. Genotyping of 20 high-risk SNP loci identified from genome-wide association studies (GWAS on esophageal, lung and gastric cancers was performed using TaqMan allelic discrimination assays. Polymorphisms were examined for deviation from Hardy-Weinberg equilibrium (HWE using Х2 test. Bonferroni correction was performed to correct the statistical significance of 20 SNPs with the risk of lung cancer. The Pearson's Х2 test was used to compare the distributions of gender, TNM stage, histopathological type, smoking and family history by lung susceptibility genotypes. Kaplan-Meier and Cox regression analyses were carried out to evaluate the associations between genetic variants and overall survival.Four of the 20 SNPs identified as high-risk SNPs in Chinese esophageal cancer showed increased risk for Chinese lung cancer, which included rs3769823 (OR = 1.26; 95% CI = 1.107-1.509; P = 0.02, rs10931936 (OR = 1.283; 95% CI = 1.100-1.495; P = 0.04, rs2244438 (OR = 1.294; 95% CI = 1.098-1.525; P = 0.04 and rs13016963 (OR = 1.268; 95% CI = 1.089-1.447; P = 0.04. All these SNPs were located at 2q33 region harboringgenes of CASP8, ALS2CR12 and TRAK2. However, none of these susceptibility SNPs was observed to be significantly associated with gender, TNM stage

  1. Shared susceptibility loci at 2q33 region for lung and esophageal cancers in high-incidence areas of esophageal cancer in northern China.

    Science.gov (United States)

    Zhao, Xue Ke; Mao, Yi Min; Meng, Hui; Song, Xin; Hu, Shou Jia; Lv, Shuang; Cheng, Rang; Zhang, Tang Juan; Han, Xue Na; Ren, Jing Li; Qi, Yi Jun; Wang, Li Dong

    2017-01-01

    Cancers from lung and esophagus are the leading causes of cancer-related deaths in China and share many similarities in terms of histological type, risk factors and genetic variants. Recent genome-wide association studies (GWAS) in Chinese esophageal cancer patients have demonstrated six high-risk candidate single nucleotide polymorphisms (SNPs). Thus, the present study aimed to determine the risk of these SNPs predisposing to lung cancer in Chinese population. A total of 1170 lung cancer patients and 1530 normal subjects were enrolled in this study from high-incidence areas for esophageal cancer in Henan, northern China. Five milliliters of blood were collected from all subjects for genotyping. Genotyping of 20 high-risk SNP loci identified from genome-wide association studies (GWAS) on esophageal, lung and gastric cancers was performed using TaqMan allelic discrimination assays. Polymorphisms were examined for deviation from Hardy-Weinberg equilibrium (HWE) using Х2 test. Bonferroni correction was performed to correct the statistical significance of 20 SNPs with the risk of lung cancer. The Pearson's Х2 test was used to compare the distributions of gender, TNM stage, histopathological type, smoking and family history by lung susceptibility genotypes. Kaplan-Meier and Cox regression analyses were carried out to evaluate the associations between genetic variants and overall survival. Four of the 20 SNPs identified as high-risk SNPs in Chinese esophageal cancer showed increased risk for Chinese lung cancer, which included rs3769823 (OR = 1.26; 95% CI = 1.107-1.509; P = 0.02), rs10931936 (OR = 1.283; 95% CI = 1.100-1.495; P = 0.04), rs2244438 (OR = 1.294; 95% CI = 1.098-1.525; P = 0.04) and rs13016963 (OR = 1.268; 95% CI = 1.089-1.447; P = 0.04). All these SNPs were located at 2q33 region harboringgenes of CASP8, ALS2CR12 and TRAK2. However, none of these susceptibility SNPs was observed to be significantly associated with gender, TNM stage, histopathological type

  2. Preliminary study on the antimicrobial susceptibility pattern related to the genotype of Vibrio vulnificus strains isolated in the north-western Adriatic Sea coastal area.

    Science.gov (United States)

    Serratore, Patrizia; Zavatta, Emanuele; Fiocchi, Eleonora; Serafini, Emanuele; Serraino, Andrea; Giacometti, Federica; Bignami, Giorgia

    2017-10-20

    V. vulnificus is a Gram-negative bacterium, commonly found in estuarine and coastal habitats, that can infect humans through seafood consumption or wound exposure. This study represents the first attempt to correlate the genotype of Vibrio vulnificus strains isolated in the north-western Adriatic Sea coastal area, with their antimicrobial susceptibility patterns. On the whole, 40 V. vulnificus strains, isolated from shellfish (n=20), different coastal water bodies (n=19), and the blood of a Carretta carretta turtle (n=1), were utilized. All strains were positive for the species-specific genes vvh A and hsp , with high variability for other markers: 55% (22 out of 40) resulted of the environmental (E) genotype ( vcg E, 16S rRNA type A, CPS2 or CPS0), 10% (4 out of 40) of the clinical (C) genotype ( vcg C, 16S rRNA type B, CPS1), and 35% (14 out of 40) of the mixed (M) genotype, possessing both E and C markers. The antimicrobial susceptibility was assayed by the diffusion method on agar, according to the Clinical Laboratory Standards Institute (CLSI), utilizing the following commercial disks (Oxoid): ampicillin (AMP), ampicillin- sulbactam (SAM), piperacillin (PRL), cefazolin (KZ), cefotaxime(CTX), ceftazidime (CAZ), imipenem (IPM), meropenem (MEM), amikacin (AK), gentamicin(CN), tetracycline(TE), ciprofloxacin (CIP), levofloxacin (LEV), trimethoprim-sulfamethoxazole (SXT), and chloramphenicol (C). 75% of the strains, (n=30) including all C strains, was sensitive to all the tested antibiotics, whereas E strains showed intermediate sensitivity to AK (2 strains), CIP and CAZ (1 strain), TE (1 strain) and resistance to KZ (1 strain), and 4 M strains showed I to AK.

  3. Metabolic rate in different rat brain areas during seizures induced by a specific delta opiate receptor agonist.

    Science.gov (United States)

    Haffmans, J; De Kloet, R; Dzoljic, M R

    1984-06-04

    The glucose utilization during specific delta opiate agonist-induced epileptiform phenomena, determined by the [14C]2-deoxyglucose technique (2-DG), was examined in various rat brain areas at different time intervals. The peak in EEG spiking response and the most intensive 2-DG uptake occurred 5 min after intraventricular (i.v.t.) administration of the delta opiate receptor agonist. The most pronounced 2-DG uptake at this time interval can be observed in the subiculum, including the CA1 hippocampal area, frontal cortex and central amygdala. A general decrease of glucose consumption, compared to control values, is observed after 10 min, in all regions, with exception of the subiculum. Since functional activity and 2-DG uptake are correlated, we suggest that the subiculum and/or CA1 area, are probably the brain regions most involved in the enkephalin-induced epileptic phenomena.

  4. Radioimmunoassay of met-enkephalin in microdissected areas of paraformaldehyde-fixed rat brain

    International Nuclear Information System (INIS)

    Correa, F.M.A.; Saavedra, J.M.

    1984-01-01

    The effects were studied of various sample preparation procedures on rat brain met-enkephalin content, measured by radioimmunoassay. Whole brain met-enkephalin content of rats killed by decapitation followed by immediate tissue freezing was similar to that of rats killed by microwave irradiation and to those of rats anesthetized with pentobarbital or halothane before killing, whether previously perfused with paraformaldehyde or not. In contrast, a decrease (up to 80%) in met-enkephalin concentrations was observed when brain samples were frozen and thawed to mimic the procedure utilized in the ''punch'' technique for analysis of discrete brain nuclei. This decrease was totally prevented by paraformaldehyde perfusion of the brain prior to sacrifice. Brain perfusion did not alter the amount of immunoassayable met-enkephalin extracted from tissue or its profile after Sephadex chromatography. Paraformaldehyde perfusion results in better morphological tissue preservation and facilitates the ''punch'' dissecting technique. Paraformaldehyde perfusion may be the procedure of choice for the measurement of neuropeptides in specific brain nuclei dissected by the ''punch'' technique

  5. Preoperative mapping of cortical language areas in adult brain tumour patients using PET and individual non-normalised SPM analyses

    International Nuclear Information System (INIS)

    Meyer, Philipp T.; Sturz, Laszlo; Schreckenberger, Mathias; Setani, Keyvan S.; Buell, Udalrich; Spetzger, Uwe; Meyer, Georg F.; Sabri, Osama

    2003-01-01

    In patients scheduled for the resection of perisylvian brain tumours, knowledge of the cortical topography of language functions is crucial in order to avoid neurological deficits. We investigated the applicability of statistical parametric mapping (SPM) without stereotactic normalisation for individual preoperative language function brain mapping using positron emission tomography (PET). Seven right-handed adult patients with left-sided brain tumours (six frontal and one temporal) underwent 12 oxygen-15 labelled water PET scans during overt verb generation and rest. Individual activation maps were calculated for P<0.005 and P<0.001 without anatomical normalisation and overlaid onto the individuals' magnetic resonance images for preoperative planning. Activations corresponding to Broca's and Wernicke's areas were found in five and six cases, respectively, for P<0.005 and in three and six cases, respectively, for P<0.001. One patient with a glioma located in the classical Broca's area without aphasic symptoms presented an activation of the adjacent inferior frontal cortex and of a right-sided area homologous to Broca's area. Four additional patients with left frontal tumours also presented activations of the right-sided Broca's homologue; two of these showed aphasic symptoms and two only a weak or no activation of Broca's area. Other frequently observed activations included bilaterally the superior temporal gyri, prefrontal cortices, anterior insulae, motor areas and the cerebellum. The middle and inferior temporal gyri were activated predominantly on the left. An SPM group analysis (P<0.05, corrected) in patients with left frontal tumours confirmed the activation pattern shown by the individual analyses. We conclude that SPM analyses without stereotactic normalisation offer a promising alternative for analysing individual preoperative language function brain mapping studies. The observed right frontal activations agree with proposed reorganisation processes, but

  6. Vertical displacement of the brain and the target area during open stereotaxic neurosurgery

    International Nuclear Information System (INIS)

    Wester, K.; Kraekenes, J.

    2001-01-01

    During stereotaxic thalamotomies, we observed that the brain surface was sinking. The study was carried out to investigate to what extent the target area also was displaced and how this would affect the accuracy of the stereotaxic procedure. In 12 thalamotomies, with the patients operated on in the sitting position, we found that the cortical surface sank 0-9 (mean 5) mm during the operation. The vertical co-ordinate of the thalamic target was consequently adjusted per-operatively, and the electrodes were advanced on additional distance of 1-5.5 (mean 3.5) mm in an attempt to compensate for the assumed sinking of the target. This per-operative adjustment was based on the surgeon's experience and the results of macro-stimulation studies. The exact location of the thalamotomy lesion, and thereby the accuracy of the adjustment, was evaluated on 3 months postoperative CT scans. These showed that the intended target was hit with a sufficient degree of accuracy in all the patients, although the vertical co-ordinate had been slightly over-adjusted, as the center of the lesion on the average was located 1 mm below the intended location. Thus, if the vertical position had not been adjusted, the lesion would on the average have been located 2.5 mm too high compared with the intended target. Patients undergoing thalamotomy and other stereotaxic procedures, where a high degree of accuracy is needed, should be operated on in the sitting position. At the thalamic level, the vertical displacement of the target should be adjusted for by additional advancement of the stereotaxic probe. On average, this compensatory adjustment should be about half the per-operative sinking of the cortical surface. (author)

  7. Hand posture classification using electrocorticography signals in the gamma band over human sensorimotor brain areas

    Science.gov (United States)

    Chestek, Cynthia A.; Gilja, Vikash; Blabe, Christine H.; Foster, Brett L.; Shenoy, Krishna V.; Parvizi, Josef; Henderson, Jaimie M.

    2013-04-01

    Objective. Brain-machine interface systems translate recorded neural signals into command signals for assistive technology. In individuals with upper limb amputation or cervical spinal cord injury, the restoration of a useful hand grasp could significantly improve daily function. We sought to determine if electrocorticographic (ECoG) signals contain sufficient information to select among multiple hand postures for a prosthetic hand, orthotic, or functional electrical stimulation system.Approach. We recorded ECoG signals from subdural macro- and microelectrodes implanted in motor areas of three participants who were undergoing inpatient monitoring for diagnosis and treatment of intractable epilepsy. Participants performed five distinct isometric hand postures, as well as four distinct finger movements. Several control experiments were attempted in order to remove sensory information from the classification results. Online experiments were performed with two participants. Main results. Classification rates were 68%, 84% and 81% for correct identification of 5 isometric hand postures offline. Using 3 potential controls for removing sensory signals, error rates were approximately doubled on average (2.1×). A similar increase in errors (2.6×) was noted when the participant was asked to make simultaneous wrist movements along with the hand postures. In online experiments, fist versus rest was successfully classified on 97% of trials; the classification output drove a prosthetic hand. Online classification performance for a larger number of hand postures remained above chance, but substantially below offline performance. In addition, the long integration windows used would preclude the use of decoded signals for control of a BCI system. Significance. These results suggest that ECoG is a plausible source of command signals for prosthetic grasp selection. Overall, avenues remain for improvement through better electrode designs and placement, better participant training

  8. Cortical thinning in cognitively normal elderly cohort of 60 to 89 year old from AIBL database and vulnerable brain areas

    Science.gov (United States)

    Lin, Zhongmin S.; Avinash, Gopal; Yan, Litao; McMillan, Kathryn

    2014-03-01

    Age-related cortical thinning has been studied by many researchers using quantitative MR images for the past three decades and vastly differing results have been reported. Although results have shown age-related cortical thickening in elderly cohort statistically in some brain regions under certain conditions, cortical thinning in elderly cohort requires further systematic investigation. This paper leverages our previously reported brain surface intensity model (BSIM)1 based technique to measure cortical thickness to study cortical changes due to normal aging. We measured cortical thickness of cognitively normal persons from 60 to 89 years old using Australian Imaging Biomarkers and Lifestyle Study (AIBL) data. MRI brains of 56 healthy people including 29 women and 27 men were selected. We measured average cortical thickness of each individual in eight brain regions: parietal, frontal, temporal, occipital, visual, sensory motor, medial frontal and medial parietal. Unlike the previous published studies, our results showed consistent age-related thinning of cerebral cortex in all brain regions. The parietal, medial frontal and medial parietal showed fastest thinning rates of 0.14, 0.12 and 0.10 mm/decade respectively while the visual region showed the slowest thinning rate of 0.05 mm/decade. In sensorimotor and parietal areas, women showed higher thinning (0.09 and 0.16 mm/decade) than men while in all other regions men showed higher thinning than women. We also created high resolution cortical thinning rate maps of the cohort and compared them to typical patterns of PET metabolic reduction of moderate AD and frontotemporal dementia (FTD). The results seemed to indicate vulnerable areas of cortical deterioration that may lead to brain dementia. These results validate our cortical thickness measurement technique by demonstrating the consistency of the cortical thinning and prediction of cortical deterioration trend with AIBL database.

  9. Quantitative pharmacological analysis of 2-125I-iodomelatonin binding sites in discrete areas of the chicken brain

    International Nuclear Information System (INIS)

    Siuciak, J.A.; Krause, D.N.; Dubocovich, M.L.

    1991-01-01

    The authors have localized and characterized 2-125I-iodomelatonin binding sites in the chicken brain using in vitro quantitative autoradiography. Binding sites were widely distributed throughout the chicken brain, predominantly in regions associated with the visual system. The specific binding of 2-125I-iodomelatonin to discrete chicken brain areas was found to be saturable, reversible, and of high affinity. The specific binding of 2-125I-iodomelatonin (75 pm) was quantitated for 40 identifiable brain regions. Eight brain regions were chosen for binding characterization and pharmacological analysis: optic tectum, Edinger-Westphal nucleus, oculomotor nucleus, nucleus rotundus, ventral supraoptic decussation, ventrolateral geniculate nucleus, neostriatum, and ectostriatum. These regions showed no rostral-caudal gradient in 2-125I-iodomelatonin specific binding, and saturation analysis revealed a single class of high-affinity sites with KD values in the range of 33-48 pM and receptor site density (Bmax) ranging from 31 to 58 fmol/mg protein. Competition experiments carried out with various indoles revealed a similar order of pharmacological affinities in these areas: melatonin greater than 6-chloromelatonin greater than methoxyluzindole greater than N-acetylserotonin greater than luzindole much greater than 5-HT greater than 5-methoxytryptamine. The affinity constants determined by quantitative autoradiography for these compounds to compete for 2-125I-iodomelatonin binding in the optic tectum correlated well with the affinities in chicken brain membranes at 25 degrees C (r = 0.966; slope = 0.845; n = 7) and 0 degree C (r = 0.946; slope = 0.379; n = 7), chicken retinal membranes (r = 0.973; slope = 0.759; n = 7), and the potency or affinity of these compounds to affect the calcium-dependent release of 3H-dopamine from the rabbit retina (r = 0.902; slope = 0.506; n = 6)

  10. Susceptibility Testing

    Science.gov (United States)

    ... Marker Bicarbonate (Total CO2) Bilirubin Blood Culture Blood Gases Blood Ketones Blood Smear Blood Typing Blood Urea ... hours depending on the method used. There are commercial tests available that offer rapid susceptibility testing and ...

  11. Hypometabolism in Posterior and Temporal Areas of the Brain is Associated with Cognitive Decline in Parkinson's Disease.

    Science.gov (United States)

    Tard, Céline; Demailly, Franck; Delval, Arnaud; Semah, Franck; Defebvre, Luc; Dujardin, Kathy; Moreau, Caroline

    2015-01-01

    Brain metabolic profiles of patients with Parkinson's disease (PD) and cognitive impairment or dementia are now available. It would be useful if data on brain metabolism were also predictive of the risk of a pejorative cognitive evolution - especially in the multidisciplinary management of advanced PD patients. The primary objective was to determine whether a specific brain metabolic pattern is associated with cognitive decline in PD. Sixteen advanced PD patients were screened for the absence of cognitive impairment (according to the Mattis dementia rating scale, MDRS) and underwent [18F]-fluorodeoxyglucose positron emission tomography brain imaging in the "off drug" state. The MDRS was scored again about two years later, categorizing patients as having significant cognitive decline (decliners) or not (stables). The two groups were then compared in terms of their brain metabolism at inclusion. There were six decliners and ten stables. Significant hypometabolism in the two precunei (Brodmann area (BA) 31), the left middle temporal gyrus (BA21) and the left fusiform gyrus (BA37) was found in the decliner group compared withthe stables. In advanced PD, a particular metabolic pattern may be associated with the onset of significant cognitive decline.

  12. Increase in seizure susceptibility in sepsis like condition explained by spiking cytokines and altered adhesion molecules level with impaired blood brain barrier integrity in experimental model of rats treated with lipopolysaccharides.

    Science.gov (United States)

    Sewal, Rakesh K; Modi, Manish; Saikia, Uma Nahar; Chakrabarti, Amitava; Medhi, Bikash

    2017-09-01

    Epilepsy is a neurological disorder characterized by recurrent unprovoked seizures. Sepsis is a condition which initiates a cascade of a surge of inflammatory mediators. Interplay between seizures and inflammation other than of brain origin is yet to be explored. The present study was designed to evaluate the seizure susceptibility in experimental models of lipopolysaccharide (LPS) induced sepsis. Experimental sepsis was induced using lipopolysaccharides in Wistar rats. Valproic acid, dexametasone were given to two different groups of animals along with LPS. Two groups of animals were subjected to administration of vehicle and LPS respectively with no other treatment. 24h later, animals were subjected to seizures by using either maximal electro shock or pentylenetetrazole. Seizures related parameters, oxidative stress and TNF-α, IL-6, IL-1β, ICAM-1, ICAM-2, VCAM-1, MMP-9 level in serum and brain samples were evaluated. Histopathological and blood brain barrier permeability studies were conducted. Seizures were decreased in valproic acid treated animals. Reduced oxidative stress was seen in dexamethasone plus valproic acid treated groups as compared to LPS alone treated group. TNF-α, IL-6, IL-1β, ICAM-1, VCAM-1, MMP-9 levels were found increased in LPS treated animals whereas a reverse observation was noted for ICAM-2 level in brain and serum. Histopathological findings confirmed the successful establishment of sepsis like state in animals. Blood brain barrier permeability was found increased in LPS treated groups of animals. Seizure susceptibility may escalate during the sepsis like inflammatory conditions and curbing the inflammatory state might reverse the phenomenon. Copyright © 2017. Published by Elsevier B.V.

  13. Brain areas associated with numbers and calculations in children: Meta-analyses of fMRI studies

    Directory of Open Access Journals (Sweden)

    Marie Arsalidou

    2018-04-01

    Full Text Available Children use numbers every day and typically receive formal mathematical training from an early age, as it is a main subject in school curricula. Despite an increase in children neuroimaging studies, a comprehensive neuropsychological model of mathematical functions in children is lacking. Using quantitative meta-analyses of functional magnetic resonance imaging (fMRI studies, we identify concordant brain areas across articles that adhere to a set of selection criteria (e.g., whole-brain analysis, coordinate reports and report brain activity to tasks that involve processing symbolic and non-symbolic numbers with and without formal mathematical operations, which we called respectively number tasks and calculation tasks. We present data on children 14 years and younger, who solved these tasks. Results show activity in parietal (e.g., inferior parietal lobule and precuneus and frontal (e.g., superior and medial frontal gyri cortices, core areas related to mental-arithmetic, as well as brain regions such as the insula and claustrum, which are not typically discussed as part of mathematical problem solving models. We propose a topographical atlas of mathematical processes in children, discuss findings within a developmental constructivist theoretical model, and suggest practical methodological considerations for future studies. Keywords: Mathematical cognition, Meta-analyses, fMRI, Children, Development, Insula

  14. Common brain areas engaged in false belief reasoning and visual perspective taking: A meta-analysis of functional brain imaging studies.

    Directory of Open Access Journals (Sweden)

    Matthias eSchurz

    2013-11-01

    Full Text Available We performed a quantitative meta-analysis of functional neuroimaging studies to identify brain areas which are commonly engaged in social and visuo-spatial perspective taking. Specifically, we compared brain activation found for visual-perspective taking to activation for false belief reasoning, a task which requires awareness of perspective to understand someone’s mistaken belief about the world which contrasts with reality. In support of a previous account by Perner & Leekam (2008, a meta-analytic conjunction analysis found activation for false belief reasoning and visual perspective taking in the left but not the right dorsal temporo-parietal junction. This fits with the idea that the left dorsal TPJ is responsible for representing different perspectives in a domain-general fashion. Moreover, the conjunction found activation in the precuneus and the left middle occipital gyrus close to the putative Extrastriate Body Area. The precuneus is linked to mental-imagery processes, which may aid in the construction of a different perspective. The Extrastriate Body Area may be engaged due to imagined body-transformations when another’s viewpoint is adopted.

  15. An HPLC tracing of the enhancer regulation in selected discrete brain areas of food-deprived rats.

    Science.gov (United States)

    Miklya, I; Knoll, B; Knoll, J

    2003-05-09

    The recent discovery of the enhancer regulation in the mammalian brain brought a different perspective to the brain-organized realization of goal-oriented behavior, which is the quintessence of plastic behavioral descriptions such as drive or motivation. According to this new approach, 'drive' means that special endogenous enhancer substances enhance the impulse-propagation-mediated release of transmitters in a proper population of enhancer-sensitive neurons, and keep these neurons in the state of enhanced excitability until the goal is reached. However, to reach any goal needs the participation of the catecholaminergic machinery, the engine of the brain. We developed a method to detect the specific enhancer effect of synthetic enhancer substances [(-)-deprenyl, (-)-PPAP, (-)-BPAP] by measuring the release of transmitters from freshly isolated selected discrete brain areas (striatum, substantia nigra, tuberculum olfactorium, locus coeruleus, raphe) by the aid of HPLC with electrochemical detection. To test the validity of the working hypothesis that in any form of goal-seeking behavior the catecholaminergic and serotonergic neurons work on a higher activity level, we compared the amount of norepinephrine, dopamine, and serotonin released from selected discrete brain areas isolated from the brain of sated and food-deprived rats. Rats were deprived of food for 48 and 72 hours, respectively, and the state of excitability of their catecholaminergic and serotonergic neurons in comparison to that of sated rats was measured. We tested the orienting-searching reflex activity of the rats in a special open field, isolated thereafter selected discrete brain areas and measured the release of norepinephrine, dopamine, and serotonin from the proper tissue samples into the organ bath. The orienting-searching reflex activity of the rats increased proportionally to the time elapsed from the last feed and the amount of dopamine released from the striatum, substantia nigra and

  16. Brain areas involved in acupuncture needling sensation of de qi: a single-photon emission computed tomography (SPECT) study.

    Science.gov (United States)

    Chen, Jia-Rong; Li, Gan-Long; Zhang, Gui-Feng; Huang, Yong; Wang, Shu-Xia; Lu, Na

    2012-12-01

    De qi is a sensory response elicited by acupuncture stimulation. According to traditional Chinese medicine (TCM), de qi is essential for clinical efficacy. However, the understanding of the neurobiological basis of de qi is still limited. To investigate the relationship between brain activation and de qi by taking a single-photon emission computed tomography (SPECT) scan while applying acupuncture at TE5. A total of 24 volunteers were randomly divided into 4 groups, and received verum or sham acupuncture at true acupuncture point TE5 or a nearby sham point according to grouping. All subjects then received a (99m)Tc-ethylcysteinate dimer (ECD) SPECT scan. All six subjects in the verum acupuncture at true acupuncture point group experienced de qi sensation; in contrast, all six subjects in the sham acupuncture at the sham point group responded with nothing other than non-sensation. Compared to the scan results from subjects who experienced non-sensation, SPECT scans from subjects with de qi sensation demonstrated significant activated points mainly located in brodmann areas 6, 8, 19, 21, 28, 33, 35, 37, 47, the parahippocampal gyrus, lentiform nucleus, claustrum and red nucleus; deactivated points were seen in brodmann areas 9 and 25. Verum acupuncture at true acupuncture points is more likely to elicit de qi sensation. De qi sensations mainly resulted in brain area activations, but not deactivations. These brain areas are related to the curative effect of Te5. The acupuncture needle sensations of de qi and sharp pain are associated with different patterns of activations and deactivations in the brain.

  17. Validating computationally predicted TMS stimulation areas using direct electrical stimulation in patients with brain tumors near precentral regions.

    Science.gov (United States)

    Opitz, Alexander; Zafar, Noman; Bockermann, Volker; Rohde, Veit; Paulus, Walter

    2014-01-01

    The spatial extent of transcranial magnetic stimulation (TMS) is of paramount interest for all studies employing this method. It is generally assumed that the induced electric field is the crucial parameter to determine which cortical regions are excited. While it is difficult to directly measure the electric field, one usually relies on computational models to estimate the electric field distribution. Direct electrical stimulation (DES) is a local brain stimulation method generally considered the gold standard to map structure-function relationships in the brain. Its application is typically limited to patients undergoing brain surgery. In this study we compare the computationally predicted stimulation area in TMS with the DES area in six patients with tumors near precentral regions. We combine a motor evoked potential (MEP) mapping experiment for both TMS and DES with realistic individual finite element method (FEM) simulations of the electric field distribution during TMS and DES. On average, stimulation areas in TMS and DES show an overlap of up to 80%, thus validating our computational physiology approach to estimate TMS excitation volumes. Our results can help in understanding the spatial spread of TMS effects and in optimizing stimulation protocols to more specifically target certain cortical regions based on computational modeling.

  18. Gamma Knife irradiation method based on dosimetric controls to target small areas in rat brains

    International Nuclear Information System (INIS)

    Constanzo, Julie; Paquette, Benoit; Charest, Gabriel; Masson-Côté, Laurence; Guillot, Mathieu

    2015-01-01

    Purpose: Targeted and whole-brain irradiation in humans can result in significant side effects causing decreased patient quality of life. To adequately investigate structural and functional alterations after stereotactic radiosurgery, preclinical studies are needed. The purpose of this work is to establish a robust standardized method of targeted irradiation on small regions of the rat brain. Methods: Euthanized male Fischer rats were imaged in a stereotactic bed, by computed tomography (CT), to estimate positioning variations relative to the bregma skull reference point. Using a rat brain atlas and the stereotactic bregma coordinates obtained from CT images, different regions of the brain were delimited and a treatment plan was generated. A single isocenter treatment plan delivering ≥100 Gy in 100% of the target volume was produced by Leksell GammaPlan using the 4 mm diameter collimator of sectors 4, 5, 7, and 8 of the Gamma Knife unit. Impact of positioning deviations of the rat brain on dose deposition was simulated by GammaPlan and validated with dosimetric measurements. Results: The authors’ results showed that 90% of the target volume received 100 ± 8 Gy and the maximum of deposited dose was 125 ± 0.7 Gy, which corresponds to an excellent relative standard deviation of 0.6%. This dose deposition calculated with GammaPlan was validated with dosimetric films resulting in a dose-profile agreement within 5%, both in X- and Z-axes. Conclusions: The authors’ results demonstrate the feasibility of standardizing the irradiation procedure of a small volume in the rat brain using a Gamma Knife

  19. Higher-order Brain Areas Associated with Real-time Functional MRI Neurofeedback Training of the Somato-motor Cortex.

    Science.gov (United States)

    Auer, Tibor; Dewiputri, Wan Ilma; Frahm, Jens; Schweizer, Renate

    2018-05-15

    Neurofeedback (NFB) allows subjects to learn self-regulation of neuronal brain activation based on information about the ongoing activation. The implementation of real-time functional magnetic resonance imaging (rt-fMRI) for NFB training now facilitates the investigation into underlying processes. Our study involved 16 control and 16 training right-handed subjects, the latter performing an extensive rt-fMRI NFB training using motor imagery. A previous analysis focused on the targeted primary somato-motor cortex (SMC). The present study extends the analysis to the supplementary motor area (SMA), the next higher brain area within the hierarchy of the motor system. We also examined transfer-related functional connectivity using a whole-volume psycho-physiological interaction (PPI) analysis to reveal brain areas associated with learning. The ROI analysis of the pre- and post-training fMRI data for motor imagery without NFB (transfer) resulted in a significant training-specific increase in the SMA. It could also be shown that the contralateral SMA exhibited a larger increase than the ipsilateral SMA in the training and the transfer runs, and that the right-hand training elicited a larger increase in the transfer runs than the left-hand training. The PPI analysis revealed a training-specific increase in transfer-related functional connectivity between the left SMA and frontal areas as well as the anterior midcingulate cortex (aMCC) for right- and left-hand trainings. Moreover, the transfer success was related with training-specific increase in functional connectivity between the left SMA and the target area SMC. Our study demonstrates that NFB training increases functional connectivity with non-targeted brain areas. These are associated with the training strategy (i.e., SMA) as well as with learning the NFB skill (i.e., aMCC and frontal areas). This detailed description of both the system to be trained and the areas involved in learning can provide valuable information

  20. Changes in the peritumoral hypoperfusion area immediately after radiosurgery for metastatic brain tumor. Analysis using 3D-SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Nemoto, Masaaki [Toho Univ., Tokyo (Japan). School of Medicine

    2001-09-01

    Sixteen patients with single metastatic brain tumor underwent SPECT using N-isopropyl-p-({sup 123}I) iodoamphetamine ({sup 123}I-IMP) before and after radiosurgery. Influence of treatment was evaluated using three-dimensional SPECT images, threshold-voxel graphs and changes in the volume of the peritumoral hypoperfusion area. A three-detector type scanner, the PRISM3000, was also used. SPECT scanning was performed for 30 minutes after intravenous administration of {sup 123}I-IMP with sequential scans every 1 minutes. The data obtained 16-30 minutes after administration were processed using a low-pass ramp filter, and three-dimensional SPECT images were constructed from these data using the Application Visualization System (AVS). Furthermore, a threshold-voxel graph was plotted and the volume of the peritumoral hypoperfusion area was calculated. SPECT was performed before radiosurgery, and 1 day, 1 week, and 1 month after, and these data were compared. Three-dimensional SPECT presented the area of peritumoral hypoperfusion as a deficit image and changes were evaluated visually. Threshold-voxel graphs were evaluated as follows: changes in voxels with a threshold of 40-50% indicated a hypoperfusion area, and changes in voxels with a threshold of 70-95% indicated a hyperperfusion area in the tumor side hemisphere. The volume of the peritumoral hypoperfusion area was calculated using the voxel difference between the tumor side and normal hemispheres. Our results showed that the peritumoral hypoperfusion area gradually decreased after an initial first-day increase following radiosurgery. Visual three-dimensional SPECT allowed us to monitor both the volume of the peritumoral hypoperfusion area of metastatic brain tumors after radiosurgery by means of a threshold-voxel graph and changes in the peritumoral hypoperfusion area. (author)

  1. Optimal use of EEG recordings to target active brain areas with transcranial electrical stimulation.

    Science.gov (United States)

    Dmochowski, Jacek P; Koessler, Laurent; Norcia, Anthony M; Bikson, Marom; Parra, Lucas C

    2017-08-15

    To demonstrate causal relationships between brain and behavior, investigators would like to guide brain stimulation using measurements of neural activity. Particularly promising in this context are electroencephalography (EEG) and transcranial electrical stimulation (TES), as they are linked by a reciprocity principle which, despite being known for decades, has not led to a formalism for relating EEG recordings to optimal stimulation parameters. Here we derive a closed-form expression for the TES configuration that optimally stimulates (i.e., targets) the sources of recorded EEG, without making assumptions about source location or distribution. We also derive a duality between TES targeting and EEG source localization, and demonstrate that in cases where source localization fails, so does the proposed targeting. Numerical simulations with multiple head models confirm these theoretical predictions and quantify the achieved stimulation in terms of focality and intensity. We show that constraining the stimulation currents automatically selects optimal montages that involve only a few (4-7) electrodes, with only incremental loss in performance when targeting focal activations. The proposed technique allows brain scientists and clinicians to rationally target the sources of observed EEG and thus overcomes a major obstacle to the realization of individualized or closed-loop brain stimulation. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Neural Processing of Calories in Brain Reward Areas Can be Modulated by Reward Sensitivity

    NARCIS (Netherlands)

    van Rijn, Inge; Griffioen-Roose, Sanne; de Graaf, Cees; Smeets, Paul A M

    A food's reward value is dependent on its caloric content. Furthermore, a food's acute reward value also depends on hunger state. The drive to obtain rewards (reward sensitivity), however, differs between individuals. Here, we assessed the association between brain responses to calories in the mouth

  3. GLP-1 Receptor Activation Modulates Appetite- and Reward-Related Brain Areas in Humans

    NARCIS (Netherlands)

    van Bloemendaal, L.; IJzerman, R.G.; ten Kulve, J.S.; Barkhof, F.; Konrad, R.J.; Drent, M.L.; Veltman, D.J.; Diamant, M.

    2014-01-01

    Gut-derived hormones, such as GLP-1, have been proposed to relay information to the brain to regulate appetite. GLP-1 receptor agonists, currently used for the treatment of type 2 diabetes (T2DM), improve glycemic control and stimulate satiety, leading to decreases in food intake and body weight. We

  4. Synaesthetic colour in the brain: beyond colour areas. A functional magnetic resonance imaging study of synaesthetes and matched controls.

    Science.gov (United States)

    van Leeuwen, Tessa M; Petersson, Karl Magnus; Hagoort, Peter

    2010-08-10

    In synaesthesia, sensations in a particular modality cause additional experiences in a second, unstimulated modality (e.g., letters elicit colour). Understanding how synaesthesia is mediated in the brain can help to understand normal processes of perceptual awareness and multisensory integration. In several neuroimaging studies, enhanced brain activity for grapheme-colour synaesthesia has been found in ventral-occipital areas that are also involved in real colour processing. Our question was whether the neural correlates of synaesthetically induced colour and real colour experience are truly shared. First, in a free viewing functional magnetic resonance imaging (fMRI) experiment, we located main effects of synaesthesia in left superior parietal lobule and in colour related areas. In the left superior parietal lobe, individual differences between synaesthetes (projector-associator distinction) also influenced brain activity, confirming the importance of the left superior parietal lobe for synaesthesia. Next, we applied a repetition suppression paradigm in fMRI, in which a decrease in the BOLD (blood-oxygenated-level-dependent) response is generally observed for repeated stimuli. We hypothesized that synaesthetically induced colours would lead to a reduction in BOLD response for subsequently presented real colours, if the neural correlates were overlapping. We did find BOLD suppression effects induced by synaesthesia, but not within the colour areas. Because synaesthetically induced colours were not able to suppress BOLD effects for real colour, we conclude that the neural correlates of synaesthetic colour experience and real colour experience are not fully shared. We propose that synaesthetic colour experiences are mediated by higher-order visual pathways that lie beyond the scope of classical, ventral-occipital visual areas. Feedback from these areas, in which the left parietal cortex is likely to play an important role, may induce V4 activation and the percept of

  5. Synaesthetic colour in the brain: beyond colour areas. A functional magnetic resonance imaging study of synaesthetes and matched controls.

    Directory of Open Access Journals (Sweden)

    Tessa M van Leeuwen

    Full Text Available BACKGROUND: In synaesthesia, sensations in a particular modality cause additional experiences in a second, unstimulated modality (e.g., letters elicit colour. Understanding how synaesthesia is mediated in the brain can help to understand normal processes of perceptual awareness and multisensory integration. In several neuroimaging studies, enhanced brain activity for grapheme-colour synaesthesia has been found in ventral-occipital areas that are also involved in real colour processing. Our question was whether the neural correlates of synaesthetically induced colour and real colour experience are truly shared. METHODOLOGY/PRINCIPAL FINDINGS: First, in a free viewing functional magnetic resonance imaging (fMRI experiment, we located main effects of synaesthesia in left superior parietal lobule and in colour related areas. In the left superior parietal lobe, individual differences between synaesthetes (projector-associator distinction also influenced brain activity, confirming the importance of the left superior parietal lobe for synaesthesia. Next, we applied a repetition suppression paradigm in fMRI, in which a decrease in the BOLD (blood-oxygenated-level-dependent response is generally observed for repeated stimuli. We hypothesized that synaesthetically induced colours would lead to a reduction in BOLD response for subsequently presented real colours, if the neural correlates were overlapping. We did find BOLD suppression effects induced by synaesthesia, but not within the colour areas. CONCLUSIONS/SIGNIFICANCE: Because synaesthetically induced colours were not able to suppress BOLD effects for real colour, we conclude that the neural correlates of synaesthetic colour experience and real colour experience are not fully shared. We propose that synaesthetic colour experiences are mediated by higher-order visual pathways that lie beyond the scope of classical, ventral-occipital visual areas. Feedback from these areas, in which the left parietal

  6. Age of second language acquisition in multilinguals has an impact on gray matter volume in language-associated brain areas.

    Science.gov (United States)

    Kaiser, Anelis; Eppenberger, Leila S; Smieskova, Renata; Borgwardt, Stefan; Kuenzli, Esther; Radue, Ernst-Wilhelm; Nitsch, Cordula; Bendfeldt, Kerstin

    2015-01-01

    Numerous structural studies have established that experience shapes and reshapes the brain throughout a lifetime. The impact of early development, however, is still a matter of debate. Further clues may come from studying multilinguals who acquired their second language at different ages. We investigated adult multilinguals who spoke three languages fluently, where the third language was learned in classroom settings, not before the age of 9 years. Multilinguals exposed to two languages simultaneously from birth (SiM) were contrasted with multinguals who acquired their first two languages successively (SuM). Whole brain voxel based morphometry revealed that, relative to SuM, SiM have significantly lower gray matter volume in several language-associated cortical areas in both hemispheres: bilaterally in medial and inferior frontal gyrus, in the right medial temporal gyrus and inferior posterior parietal gyrus, as well as in the left inferior temporal gyrus. Thus, as shown by others, successive language learning increases the volume of language-associated cortical areas. In brains exposed early on and simultaneously to more than one language, however, learning of additional languages seems to have less impact. We conclude that - at least with respect to language acquisition - early developmental influences are maintained and have an effect on experience-dependent plasticity well into adulthood.

  7. Age of second language acquisition in multilinguals has an impact on grey matter volume in language-associated brain areas

    Directory of Open Access Journals (Sweden)

    Anelis eKaiser

    2015-06-01

    Full Text Available Numerous structural studies have established that experience shapes and reshapes the brain throughout a lifetime. The impact of early development, however, is still a matter of debate. Further clues may come from studying multilinguals who acquired their second language at different ages. We investigated adult multilinguals who spoke three languages fluently, where the third language was learned in classroom settings, not before the age of 9 years. Multilinguals exposed to 2 languages simultaneously from birth (SiM were contrasted with multinguals who acquired their first two languages successively (SuM. Whole brain voxel based morphometry revealed that, relative to SuM, SiM have significantly lower grey matter volume in several language-associated cortical areas in both hemispheres: bilaterally in medial and inferior frontal gyrus, in the right medial temporal gyrus and inferior posterior parietal gyrus, as well as in the left inferior frontal gyrus. Thus, as shown by others, successive language learning increases the volume of language-associated cortical areas. In brains exposed early on and simultaneously to more than one language, however, learning of additional languages seems to have less impact. We conclude that - at least with respect to language acquisition - early developmental influences are maintained and influence experience-dependent plasticity well into adulthood.

  8. Magnetic susceptibility imaging with a nonionic contrast agent

    International Nuclear Information System (INIS)

    Cacheris, W.; Rocklage, S.M.; Quay, S.; Dow, W.; Love, D.; Worah, D.; Lim, K.

    1988-01-01

    The magnetic susceptibility mechanism for MR imaging contrast enhancement has the advantage of providing useful information, such as cerebral blood flow, without crossing the blood-brain barrier. In this paper the authors report the use of a highly effective, relatively nontoxic chelate as a magnetic susceptibility agent. Dy-DTPA-bis(methylamide) (Dy-DTPA-BMA) has an extremely low acute toxicity (LD-50, intravenous, mice ∼ 40 mmol/kg). Doses of 1 mmol/kg and 2 mmol/kg Dy-DTPA-BMA lowered the initial signal intensity 63% to 57%, respectively. The utility of this technique in detecting areas of reduced blood flow within the brain was demonstrated by imaging a rabbit with a cerebral perfusion deficit

  9. Diminished Dentate Gyrus Filtering of Cortical Input Leads to Enhanced Area Ca3 Excitability after Mild Traumatic Brain Injury.

    Science.gov (United States)

    Folweiler, Kaitlin A; Samuel, Sandy; Metheny, Hannah E; Cohen, Akiva S

    2018-04-06

    Mild traumatic brain injury (mTBI) disrupts hippocampal function and can lead to long-lasting episodic memory impairments. The encoding of episodic memories relies on spatial information processing within the hippocampus. As the primary entry point for spatial information into the hippocampus, the dentate gyrus is thought to function as a physiological gate, or filter, of afferent excitation before reaching downstream area Cornu Ammonis (CA3). Although injury has previously been shown to alter dentate gyrus network excitability, it is unknown whether mTBI affects dentate gyrus output to area CA3. In this study, we assessed hippocampal function, specifically the interaction between the dentate gyrus and CA3, using behavioral and electrophysiological techniques in ex vivo brain slices 1 week following mild lateral fluid percussion injury (LFPI). Behaviorally, LFPI mice were found to be impaired in an object-place recognition task, indicating that spatial information processing in the hippocampus is disrupted. Extracellular recordings and voltage-sensitive dye imaging demonstrated that perforant path activation leads to the aberrant spread of excitation from the dentate gyrus into area CA3 along the mossy fiber pathway. These results suggest that after mTBI, the dentate gyrus has a diminished capacity to regulate cortical input into the hippocampus, leading to increased CA3 network excitability. The loss of the dentate filtering efficacy reveals a potential mechanism by which hippocampal-dependent spatial information processing is disrupted, and may contribute to memory dysfunction after mTBI.

  10. Increase in cocaine- and amphetamine-regulated transcript (CART) in specific areas of the mouse brain by acute caffeine administration.

    Science.gov (United States)

    Cho, Jin Hee; Cho, Yun Ha; Kim, Hyo Young; Cha, Seung Ha; Ryu, Hyun; Jang, Wooyoung; Shin, Kyung Ho

    2015-04-01

    Caffeine produces a variety of behavioral effects including increased alertness, reduced food intake, anxiogenic effects, and dependence upon repeated exposure. Although many of the effects of caffeine are mediated by its ability to block adenosine receptors, it is possible that other neural substrates, such as cocaine- and amphetamine-regulated transcript (CART), may be involved in the effects of caffeine. Indeed, a recent study demonstrated that repeated caffeine administration increases CART in the mouse striatum. However, it is not clear whether acute caffeine administration alters CART in other areas of the brain. To explore this possibility, we investigated the dose- and time-dependent changes in CART immunoreactivity (CART-IR) after a single dose of caffeine in mice. We found that a high dose of caffeine (100 mg/kg) significantly increased CART-IR 2 h after administration in the nucleus accumbens shell (AcbSh), dorsal bed nucleus of the stria terminalis (dBNST), central nucleus of the amygdala (CeA), paraventricular hypothalamic nucleus (PVN), arcuate hypothalamic nucleus (Arc), and locus coeruleus (LC), and returned to control levels after 8 h. But this increase was not observed in other brain areas. In addition, caffeine administration at doses of 25 and 50 mg/kg appears to produce dose-dependent increases in CART-IR in these brain areas; however, the magnitude of increase in CART-IR observed at a dose of 50 mg/kg was similar or greater than that observed at a dose of 100 mg/kg. This result suggests that CART-IR in AcbSh, dBNST, CeA, PVN, Arc, and LC is selectively affected by caffeine administration. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Self-identification with another person's face: the time relevant role of multimodal brain areas in the enfacement illusion.

    Science.gov (United States)

    Bufalari, Ilaria; Porciello, Giuseppina; Sperduti, Marco; Minio-Paluello, Ilaria

    2015-04-01

    The illusory subjective experience of looking at one's own face while in fact looking at another person's face can surprisingly be induced by simple synchronized visuotactile stimulation of the two faces. A recent study (Apps MA, Tajadura-Jiménez A, Sereno M, Blanke O, Tsakiris M. Cereb Cortex. First published August 20, 2013; doi:10.1093/cercor/bht199) investigated for the first time the role of visual unimodal and temporoparietal multimodal brain areas in the enfacement illusion and suggested a model in which multisensory mechanisms are crucial to construct and update self-face representation. Copyright © 2015 the American Physiological Society.

  12. Response of lactate metabolism in brain glucosensing areas of rainbow trout (Oncorhynchus mykiss) to changes in glucose levels.

    Science.gov (United States)

    Otero-Rodiño, Cristina; Librán-Pérez, Marta; Velasco, Cristina; Álvarez-Otero, Rosa; López-Patiño, Marcos A; Míguez, Jesús M; Soengas, José L

    2015-12-01

    There is no evidence in fish brain demonstrating the existence of changes in lactate metabolism in response to alterations in glucose levels. We induced in rainbow trout through intraperitoneal (IP) treatments, hypoglycaemic or hyperglycaemic changes to assess the response of parameters involved in lactate metabolism in glucosensing areas like hypothalamus and hindbrain. To distinguish those effects from those induced by peripheral changes in the levels of metabolites or hormones, we also carried out intracerebroventricular (ICV) treatments with 2-deoxy-D-glucose (2-DG, a non-metabolizable glucose analogue thus inducing local glucopenia) or glucose. Finally, we also incubated hypothalamus and hindbrain in vitro in the presence of increased glucose concentrations. The changes in glucose availability were in general correlated to changes in the amount of lactate in both areas. However, when we assessed in these areas the response of parameters related to lactate metabolism, the results obtained were contradictory. The increase in glucose levels did not produce in general the expected changes in those pathways with only a minor increase in their capacity of lactate production. The decrease in glucose levels was, however, more clearly related to a decreased capacity of the pathways involved in the production and use of lactate, and this was especially evident after ICV treatment with 2-DG in both areas. In conclusion, the present results while addressing the existence of changes in lactate metabolism after inducing changes in glucose levels in brain glucosensing areas only partially support the possible existence of an astrocyte-neuron lactate shuttle in hypothalamus and hindbrain of rainbow trout relating glucose availability to lactate production and use.

  13. Local Anesthesia at ST36 to Reveal Responding Brain Areas to deqi

    Directory of Open Access Journals (Sweden)

    Ling-min Jin

    2014-01-01

    Full Text Available Background. Development of non-deqi control is still a challenge. This study aims to set up a potential approach to non-deqi control by using lidocaine anesthesia at ST36. Methods. Forty healthy volunteers were recruited and they received two fMRI scans. One was accompanied with manual acupuncture at ST36 (DQ group, and another was associated with both local anesthesia and manual acupuncture at the same acupoint (LA group. Results. Comparing to DQ group, more than 90 percent deqi sensations were reduced by local anesthesia in LA group. The mainly activated regions in DQ group were bilateral IFG, S1, primary motor cortex, IPL, thalamus, insula, claustrum, cingulate gyrus, putamen, superior temporal gyrus, and cerebellum. Surprisingly only cerebellum showed significant activation in LA group. Compared to the two groups, bilateral S1, insula, ipsilateral IFG, IPL, claustrum, and contralateral ACC were remarkably activated. Conclusions. Local anesthesia at ST36 is able to block most of the deqi feelings and inhibit brain responses to deqi, which would be developed into a potential approach for non-deqi control. Bilateral S1, insula, ipsilateral IFG, IPL, claustrum, and contralateral ACC might be the key brain regions responding to deqi.

  14. Application of stereological methods to estimate post-mortem brain surface area using 3T MRI

    DEFF Research Database (Denmark)

    Furlong, Carolyn; García-Fiñana, Marta; Puddephat, Michael

    2013-01-01

    The Cavalieri and Vertical Sections methods of design based stereology were applied in combination with 3 tesla (i.e. 3T) Magnetic Resonance Imaging (MRI) to estimate cortical and subcortical volume, area of the pial surface, area of the grey-white matter boundary, and thickness of the cerebral...

  15. The Rat Homolog of the Schizophrenia Susceptibility Gene ZNF804A Is Highly Expressed during Brain Development, Particularly in Growth Cones

    DEFF Research Database (Denmark)

    Hinna, Katja Hvid; Rich, Karen; Fex Svenningsen, Åsa

    2015-01-01

    it decreases towards adult levels. This time point is developmentally the equivalent to the second trimester of fetal development in humans. An exception to this expression pattern is the hippocampus where the expression of Zfp804A appears to increase again in the adult brain. Using laser capture...... developmental mechanisms are suggested in the pathophysiology for schizophrenia, expression of Zfp804A, the rat homolog of ZNF804A, was investigated in the developing rat brain. We found that expression of Zfp804A in most brain regions is developmentally regulated and peaks around birth, where after...... expression was therefore investigated with immunochemistry in such cultures. Interestingly, before day 4, the protein is mostly found in the perinuclear region of the cell but at day 4, ZFP804A was instead found throughout the cell and particularly in the growth cones. In conclusion we demonstrate that Zfp...

  16. Different distributions of the 5-HT reuptake complex and the postsynaptic 5-HT(2A) receptors in Brodmann areas and brain hemispheres.

    Science.gov (United States)

    Rosel, Pilar; Arranz, Belén; Urretavizcaya, Mikel; Oros, Miguel; San, Luis; Vallejo, Julio; Navarro, Miguel Angel

    2002-08-30

    The aim of the present study was to determine the distribution of the presynaptic 5-HT reuptake complex and the 5-HT(2A) receptors through Brodmann areas from two control subjects, together with the possible existence of laterality between both brain hemispheres. A left laterality was observed in the postsynaptic 5-HT(2A) binding sites, with significantly higher B(max) values in the left frontal and cingulate cortex. In frontal cortex, [3H]imipramine and [3H]paroxetine binding showed the highest B(max) values in areas 25, 10 and 11. In cingulate cortex, the highest [3H]imipramine and [3H]paroxetine B(max) values were noted in Brodmann area 33 followed by area 24, while postsynaptic 5-HT(2A) receptors were mainly distributed through Brodmann areas 23 and 29. In temporal cortex, the highest [3H]imipramine and [3H]paroxetine B(max) was noted in Brodmann areas 28 and 34, followed by areas 35 and 38. All Brodmann areas from parietal cortex (1, 2, 3, 4, 5, 6, 7, 39, 40 and 43) showed similar presynaptic and postsynaptic binding values. In occipital cortex no differences were observed with regard to the brain hemisphere or to the Brodmann area (17, 18 and 19). These results suggest the need to carefully define the brain hemisphere and the Brodmann areas studied, as well to avoid comparisons between studies including different Brodmann areas or brain hemispheres.

  17. [Intensity of pentose phosphate metabolism of carbohydrates in various brain areas in normal and starved animals].

    Science.gov (United States)

    Kerimov, B F

    2002-01-01

    The activities of key enzymes of pentose phosphate pathway, glucose-6-phosphate dehydrogenase (G-6 PD) and 6-phosphogluconate dehydrogenase (6-PGD), were studied in cytoplasmatic fractions of brain cortical (limbic, orbital, sensorimotor cortex) and subcortical (myelencefalon, mesencefalon, hypothalamus) structures of rats subjected to starvation for 1, 2, 3, 5 and 7 days. Short-term starvation (1-3 days) caused activation of 6-GPD and 6-PGD both in cortical and subcortical structures. Long-term starvation for 5-7 days caused a decrease of activities of the pentose phosphate pathway enzymes in all studied structures. It is suggested that enzymes of pentose phosphate pathway in nervous tissues are functionally and metabolically related to glutathione system and during starvation they indirectly participate in the regulation lipid peroxidation processes.

  18. [Language Functions in the Frontal Association Area: Brain Mechanisms That Create Language].

    Science.gov (United States)

    Yamamoto, Kayako; Sakai, Kuniyoshi L

    2016-11-01

    Broca's area is known to be critically involved in language processing for more than 150 years. Recent neuroimaging techniques, including functional magnetic resonance imaging (fMRI) and diffusion MRI, enabled the subdivision of Broca's area based on both functional and anatomical aspects. Networks among the frontal association areas, especially the left inferior frontal gyrus (IFG), and other cortical regions in the temporal/parietal association areas, are also important for language-related information processing. Here, we review how neuroimaging studies, combined with research paradigms based on theoretical linguistics, have contributed to clarifying the critical roles of the left IFG in syntactic processing and those of language-related networks, including cortical and cerebellar regions.

  19. Functional connectivity between somatosensory and motor brain areas predicts individual differences in motor learning by observing.

    Science.gov (United States)

    McGregor, Heather R; Gribble, Paul L

    2017-08-01

    Action observation can facilitate the acquisition of novel motor skills; however, there is considerable individual variability in the extent to which observation promotes motor learning. Here we tested the hypothesis that individual differences in brain function or structure can predict subsequent observation-related gains in motor learning. Subjects underwent an anatomical MRI scan and resting-state fMRI scans to assess preobservation gray matter volume and preobservation resting-state functional connectivity (FC), respectively. On the following day, subjects observed a video of a tutor adapting her reaches to a novel force field. After observation, subjects performed reaches in a force field as a behavioral assessment of gains in motor learning resulting from observation. We found that individual differences in resting-state FC, but not gray matter volume, predicted postobservation gains in motor learning. Preobservation resting-state FC between left primary somatosensory cortex and bilateral dorsal premotor cortex, primary motor cortex, and primary somatosensory cortex and left superior parietal lobule was positively correlated with behavioral measures of postobservation motor learning. Sensory-motor resting-state FC can thus predict the extent to which observation will promote subsequent motor learning. NEW & NOTEWORTHY We show that individual differences in preobservation brain function can predict subsequent observation-related gains in motor learning. Preobservation resting-state functional connectivity within a sensory-motor network may be used as a biomarker for the extent to which observation promotes motor learning. This kind of information may be useful if observation is to be used as a way to boost neuroplasticity and sensory-motor recovery for patients undergoing rehabilitation for diseases that impair movement such as stroke. Copyright © 2017 the American Physiological Society.

  20. Opposite modulation of brain stimulation reward by NMDA and AMPA receptors in the ventral tegmental area.

    Directory of Open Access Journals (Sweden)

    Charles eDucrot

    2013-10-01

    Full Text Available Previous studies have shown that blockade of ventral midbrain (VM glutamate N-Methyl-D-Aspartate (NMDA receptors induces reward, stimulates forward locomotion and enhances brain stimulation reward. Glutamate induces two types of excitatory response on VM neurons, a fast and short lasting depolarisation mediated by a-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA receptors and a longer lasting depolarization mediated by NMDA receptors. A role for the two glutamate receptors in modulation of VM neuronal activity is evidenced by the functional change in AMPA and NMDA synaptic responses that result from repeated exposure to reward. Since both receptors contribute to the action of glutamate on VM neuronal activity, we studied the effects of VM AMPA and NMDA receptor blockade on reward induced by electrical brain stimulation. Experiments were performed on rats trained to self-administer electrical pulses in the medial posterior mesencephalon. Reward thresholds were measured with the curve-shift paradigm before and for two hours after bilateral VM microinjections of the AMPA antagonist, NBQX (2,3,-Dioxo-6-nitro-1,2,3,4-tetrahydrobenzo(fquinoxaline-7-sulfonamide, 0, 80, and 800 pmol/0.5ul/side and of a single dose (0.825 nmol/0.5ul/side of the NMDA antagonist, PPPA (2R,4S-4-(3-Phosphonopropyl-2-piperidinecarboxylic acid. NBQX produced a dose-dependent increase in reward threshold with no significant change in maximum rate of responding. Whereas PPPA injected at the same VM sites produced a significant time dependent decrease in reward threshold and increase in maximum rate of responding. We found a negative correlation between the magnitude of the attenuation effect of NBQX and the enhancement effect of PPPA; moreover, NBQX and PPPA were most effective when injected respectively into the anterior and posterior VM. These results suggest that glutamate acts on different receptor sub-types, most likely located on different VM neurons, to modulate

  1. Creatine kinase B-driven energy transfer in the brain is important for habituation and spatial learning behaviour, mossy fibre field size and determination of seizure susceptibility.

    NARCIS (Netherlands)

    Jost, C.R.; Zee, C.E.E.M. van der; Zandt, H.J.A. in t; Oerlemans, F.T.J.J.; Verheij, M.M.M.; Streijger, F.; Fransen, J.A.M.; Deursen, J.; Heerschap, A.; Cools, A.R.; Wieringa, B.

    2002-01-01

    Creatine kinases are important in maintaining cellular-energy homeostasis, and neuroprotective effects have been attributed to the administration of creatine and creatine-like compounds. Herein we examine whether ablation of the cytosolic brain-type creatine kinase (B-CK) in mice has detrimental

  2. Creatine kinase B-driven energy transfer in the brain is important for habituation and spatial learning behaviour, mossy fibre field size and determination of seizure susceptibility

    NARCIS (Netherlands)

    Jost, C.R.; Zee, C.E.E.M. van der; Zandt, H.J.A. in t; Oerlemans, F.T.J.J.; Verheij, M.M.M.; Streijger, F.; Fransen, J.A.M.; Heerschap, A.; Cools, A.R.; Wieringa, B.

    2002-01-01

    Creatine kinases are important in maintaining cellular-energy homeostasis, and neuroprotective effects have been attributed to the administration of creatine and creatine-like compounds. Herein we examine whether ablation of the cytosolic brain-type creatine kinase (B-CK) in mice has detrimental

  3. Incidence of Brain Infarcts, Cognitive Change, and Risk of Dementia in the General Population: The AGES-Reykjavik Study (Age Gene/Environment Susceptibility-Reykjavik Study).

    Science.gov (United States)

    Sigurdsson, Sigurdur; Aspelund, Thor; Kjartansson, Olafur; Gudmundsson, Elias F; Jonsdottir, Maria K; Eiriksdottir, Gudny; Jonsson, Palmi V; van Buchem, Mark A; Gudnason, Vilmundur; Launer, Lenore J

    2017-09-01

    The differentiation of brain infarcts by region is important because their cause and clinical implications may differ. Information on the incidence of these lesions and association with cognition and dementia from longitudinal population studies is scarce. We investigated the incidence of infarcts in cortical, subcortical, cerebellar, and overall brain regions and how prevalent and incident infarcts associate with cognitive change and incident dementia. Participants (n=2612, 41% men, mean age 74.6±4.8) underwent brain magnetic resonance imaging for the assessment of infarcts and cognitive testing at baseline and on average 5.2 years later. Incident dementia was assessed according to the international guidelines. Twenty-one percent of the study participants developed new infarcts. The risk of incident infarcts in men was higher than the risk in women (1.8; 95% confidence interval, 1.5-2.3). Persons with both incident and prevalent infarcts showed steeper cognitive decline and had almost double relative risk of incident dementia (1.7; 95% confidence interval, 1.3-2.2) compared with those without infarcts. Persons with new subcortical infarcts had the highest risk of incident dementia compared with those without infarcts (2.6; 95% confidence interval, 1.9-3.4). Men are at greater risk of developing incident brain infarcts than women. Persons with incident brain infarcts decline faster in cognition and have an increased risk of dementia compared with those free of infarcts. Incident subcortical infarcts contribute more than cortical and cerebellar infarcts to incident dementia which may indicate that infarcts of small vessel disease origin contribute more to the development of dementia than infarcts of embolic origin in larger vessels. © 2017 American Heart Association, Inc.

  4. Neuronal substrates underlying stress resilience and susceptibility in rats

    DEFF Research Database (Denmark)

    Febbraro, Fabia; Svenningsen, Katrine; Thao Phuong Tran

    2017-01-01

    attention has been devoted to understand resiliency to stress. The aim of the present study was to identify changes in neuronal activity, associated with stress-resilient and stress-susceptible chronic mild stress endophenotypes, by examining c-Fos expression in 13 different brain areas. Changes in c...... responses was done by semi-automated profile counting procedures and design-based stereology. RESULTS: Exposure to chronic mild stress significantly altered c-Fos expression in a total of 6 out of 13 investigated areas. Chronic mild stress was found to suppress the c-Fos response within the magnocellular...

  5. The Rat Homolog of the Schizophrenia Susceptibility Gene ZNF804A Is Highly Expressed during Brain Development, Particularly in Growth Cones.

    Directory of Open Access Journals (Sweden)

    Katja Hvid Hinna

    Full Text Available A single nucleotide polymorphism in the ZNF804A gene, rs1344706, is associated with schizophrenia. The polymorphism has been suggested to alter fetal expression of ZNF804A. It has also been reported to be associated with altered cortical functioning and neural connectivity in the brain. Since developmental mechanisms are suggested in the pathophysiology for schizophrenia, expression of Zfp804A, the rat homolog of ZNF804A, was investigated in the developing rat brain. We found that expression of Zfp804A in most brain regions is developmentally regulated and peaks around birth, where after it decreases towards adult levels. This time point is developmentally the equivalent to the second trimester of fetal development in humans. An exception to this expression pattern is the hippocampus where the expression of Zfp804A appears to increase again in the adult brain. Using laser capture and quantitative PCR we found that Zfp804A mRNA expression in the adult rat hippocampus is highest in the CA1 sub region, where the overall firing rates of neurons is higher than in the CA3 region. In cultured cortical neurons Zfp804A mRNA expression peaked at day 4 and then decreased. The ZFP804A protein expression was therefore investigated with immunochemistry in such cultures. Interestingly, before day 4, the protein is mostly found in the perinuclear region of the cell but at day 4, ZFP804A was instead found throughout the cell and particularly in the growth cones. In conclusion we demonstrate that Zfp804A increases in the rat brain at the time of birth, coinciding with neuronal differentiation. We also show that ZFP804A is localized to growth cones of growing neurites. These data implicate ZFP804A in growth cone function and neurite elongation. The polymorphism rs1344706 lowers expression of ZNF804A during prenatal brain development. This may affect ZNF804A's role in cone function and neurite elongation leading to synaptic deficits and altered neural connectivity.

  6. Deafferentation in thalamic and pontine areas in severe traumatic brain injury.

    Science.gov (United States)

    Laouchedi, M; Galanaud, D; Delmaire, C; Fernandez-Vidal, S; Messé, A; Mesmoudi, S; Oulebsir Boumghar, F; Pélégrini-Issac, M; Puybasset, L; Benali, H; Perlbarg, V

    2015-07-01

    Severe traumatic brain injury (TBI) is characterized mainly by diffuse axonal injuries (DAI). The cortico-subcortical disconnections induced by such fiber disruption play a central role in consciousness recovery. We hypothesized that these cortico-subcortical deafferentations inferred from diffusion MRI data could differentiate between TBI patients with favorable or unfavorable (death, vegetative state, or minimally conscious state) outcome one year after injury. Cortico-subcortical fiber density maps were derived by using probabilistic tractography from diffusion tensor imaging data acquired in 24 severe TBI patients and 9 healthy controls. These maps were compared between patients and controls as well as between patients with favorable (FO) and unfavorable (UFO) 1-year outcome to identify the thalamo-cortical and ponto-thalamo-cortical pathways involved in the maintenance of consciousness. Thalamo-cortical and ponto-thalamo-cortical fiber density was significantly lower in TBI patients than in healthy controls. Comparing FO and UFO TBI patients showed thalamo-cortical deafferentation associated with unfavorable outcome for projections from ventral posterior and intermediate thalamic nuclei to the associative frontal, sensorimotor and associative temporal cortices. Specific ponto-thalamic deafferentation in projections from the upper dorsal pons (including the reticular formation) was also associated with unfavorable outcome. Fiber density of cortico-subcortical pathways as measured from diffusion MRI tractography is a relevant candidate biomarker for early prediction of one-year favorable outcome in severe TBI. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  7. Effect of whole body neutron irradiation on certain enzyme activities in different brain areas in mice

    International Nuclear Information System (INIS)

    Kotb, M.A.; Ashour, A.M.; El-Bassiouni, E.A.

    1994-01-01

    Male swiss albino mice were exposed to whole-body irradiation by fast neutrons of 14 MeV average energy. Two single doses of 0.08 sievert and 0.16 sievert were used, corresponding to fluences of 1.27 X 10 8 and 2.54 X 10 8 n/cm 2 respectively. Two enzymes were assessed in different layers of the cerebrum and cerebellum of mouse brain. Changes in the activities of acid phosphatase (ACP) and succinic dehydrogenase (SDH) were taken to measure alterations in lysosomal and mitochondrial functions respectively. The degrees of lysosomal affection in different layers of the cerebrum were not uniform, while changes in A activity were very prominent in certain layers (e.g. external pyramidal layer, polymorphous cells layer and white matter), they were practically absent in others (e.g. internal pyramidal layer). Stronger effect was noted in the tissue layers of the cerebellum. The activity of SDH decreased as result of fast neutron irradiation. The response was more apparent for this enzyme than for ACP. This indicates more liability for a decrease in energy metabolism with consequent effect on behavioural and physiological functions under central nervous system control. 4 figs., 4 tabs

  8. Effects of deep brain stimulation of the peduncolopontine area on working memory tasks in patients with Parkinson's disease.

    Science.gov (United States)

    Costa, Alberto; Carlesimo, Giovanni Augusto; Caltagirone, Carlo; Mazzone, Paolo; Pierantozzi, Mariangela; Stefani, Alessandro; Peppe, Antonella

    2010-01-01

    The present paper was aimed at investigating the effect of low-frequency electrical stimulation (25 Hz) of the peduncolopontine (PPN) area on working memory (WM) functioning in patients with Parkinson's disease (PD). Five PD patients who underwent simultaneous PPN area- and subthalamic nucleus-deep brain stimulation (DBS) implantation participated in the study. PD patients were evaluated in the morning at least 12 h after antiparkinsonian therapy withdrawal in two conditions: i) after continuous PPN area stimulation (Off Therapy/On PPN: "On" condition); ii) at least 120 min after PPN area had been switched "Off" (Off Ther/Off PPN: "Off" condition). The experimental WM task consisted of an n-back paradigm with verbal and visual-object stimuli. PD patients showed a consistent response time decrease on both the verbal and the visual-object tasks passing from the "Off" to the "On" condition (p processing of information in the content of WM, possibly through the modulation of the attentional resources.

  9. A landslide susceptibility assessment in urban areas based on existing data: an example from the Iguaná Valley, Medellín City, Colombia

    Czech Academy of Sciences Publication Activity Database

    Klimeš, Jan; Rios Escobar, V.

    2010-01-01

    Roč. 10, č. 10 (2010), s. 2067-2079 ISSN 1561-8633 R&D Projects: GA ČR GP205/09/P383 Institutional research plan: CEZ:AV0Z30460519 Keywords : landslide susceptibility assessment * Colombia * Medellín Subject RIV: DE - Earth Magnetism, Geodesy, Geography Impact factor: 1.792, year: 2010 http://www.nat-hazards-earth-syst-sci.net/10/2067/2010/nhess-10-2067-2010.html

  10. Brain tumor - children

    Science.gov (United States)

    ... children; Neuroglioma - children; Oligodendroglioma - children; Meningioma - children; Cancer - brain tumor (children) ... The cause of primary brain tumors is unknown. Primary brain tumors may ... (spread to nearby areas) Cancerous (malignant) Brain tumors ...

  11. Brain Basics: Know Your Brain

    Science.gov (United States)

    ... however, the brain is beginning to relinquish its secrets. Scientists have learned more about the brain in ... through the activity of these lobes. At the top of each temporal lobe is an area responsible ...

  12. Cerebral malaria: susceptibility weighted MRI

    Directory of Open Access Journals (Sweden)

    Vinit Baliyan

    2015-03-01

    Full Text Available Cerebral malaria is one of the fatal complications of Plasmodium falciparum infection. Pathogenesis involves cerebral microangiopathy related to microvascular plugging by infected red blood cells. Conventional imaging with MRI and CT do not reveal anything specific in case of cerebral malaria. Susceptibility weighted imaging, a recent advance in the MRI, is very sensitive to microbleeds related to microangiopathy. Histopathological studies in cerebral malaria have revealed microbleeds in brain parenchyma secondary to microangiopathy. Susceptibility weighted imaging, being exquisitely sensitive to microbleeds may provide additional information and improve the diagnostic accuracy of MRI in cerebral malaria.

  13. PI3 kinase is involved in cocaine behavioral sensitization and its reversal with brain area specificity

    International Nuclear Information System (INIS)

    Zhang Xiuwu; Mi Jing; Wetsel, William C.; Davidson, Colin; Xiong Xieying; Chen Qiang; Ellinwood, Everett H.; Lee, Tong H.

    2006-01-01

    Phosphatidylinositol 3-kinase (PI3K) is an important signaling molecule involved in cell differentiation, proliferation, survival, and phagocytosis, and may participate in various brain functions. To determine whether it is also involved in cocaine sensitization, we measured the p85α/p110 PI3K activity in the nuclear accumbens (NAc) shell, NAc core, and prefrontal cortex (PFC) following establishment of cocaine sensitization and its subsequent reversal. Naive rats were rank-ordered and split into either daily cocaine or saline pretreatment group based on their locomotor responses to an acute cocaine injection (7.5 mg/kg, i.p.). These two groups were then injected with cocaine (40 mg/kg, s.c.) or saline for 4 consecutive days followed by 9-day withdrawal. Cocaine sensitization was subsequently reversed by 5 daily injections of the D 1 /D 2 agonist pergolide (0.1 mg/kg, s.c.) in combination with the 5-HT 3 antagonist ondansetron (0.2 mg/kg, s.c., 3.5 h after pergolide injection). After another 9-day withdrawal, behavioral cocaine sensitization and its reversal were confirmed with an acute cocaine challenge (7.5 mg/kg, i.p.), and animals were sacrificed the next day for measurement of p85α/p110 PI3K activity. Cocaine-sensitized animals exhibited increased PI3K activity in the NAc shell, and this increase was reversed by combined pergolide/ondansetron treatment, which also reversed behavioral sensitization. In the NAc core and PFC, cocaine sensitization decreased and increased the PI3K activity, respectively. These changes, in contrast to that in the NAc shell, were not normalized following the reversal of cocaine-sensitization. Interestingly, daily injections of pergolide alone in saline-pretreated animals induced PI3K changes that were similar to the cocaine sensitization-associated changes in the NAc core and PFC but not the NAc shell; furthermore, these changes in saline-pretreated animals were prevented by ondansetron given 3.5 h after pergolide. The present

  14. Acetylcholinesterase inhibition in cognition-relevant brain areas of mice treated with a nootropic Amazonian herbal (Marapuama).

    Science.gov (United States)

    Figueiró, M; Ilha, J; Pochmann, D; Porciúncula, L O; Xavier, L L; Achaval, M; Nunes, D S; Elisabetsky, E

    2010-10-01

    The goal of acetylcholinesterase inhibitors (AChEIs) used to treat Alzheimer's patients is an improvement in cholinergic transmission. While currently available AChEIs have limited success, a huge impediment to the development of newer ones is access to the relevant brain areas. Promnesic, anti-amnesic and AChEI properties were identified in a standardized ethanol extract from Ptychopetalum olacoides (POEE), a medicinal plant favored by the elderly in Amazon communities. The purpose of this study was to provide conclusive evidence that orally given POEE induces AChE inhibition in brain areas relevant to cognition. Histochemistry experiments confirmed that the anticholinesterase compound(s) present in POEE are orally bioavailable, inducing meaningful AChE inhibition in the hippocampus CA1 (∼33%) and CA3 (∼20%), and striatum (∼17%). Ellman's colorimetric analysis revealed that G1 and G4 AChE isoforms activities were markedly inhibited (66 and 72%, respectively) in hippocampus and frontal cortex (50 and 63%, respectively), while G4 appeared to be selectively inhibited (72%) in the striatum. Western blotting showed that POEE did not induce significant changes in the AChE immunocontent suggesting that its synthesis is not extensively modified. This study provides definitive proof of meaningful anticholinesterase activity compatible with the observed promnesic and anti-amnesic effects of POEE in mice, reaffirming the potential of this extract for treating neurodegenerative conditions where a hypofunctioning cholinergic neurotransmission is prominent. Adequate assessment of the safety and efficacy of this extract and/or its isolated active compound(s) are warranted. 2010 Elsevier GmbH. All rights reserved.

  15. Activation changes in zebra finch (Taeniopygia guttata) brain areas evoked by alterations of the earth magnetic field.

    Science.gov (United States)

    Keary, Nina; Bischof, Hans-Joachim

    2012-01-01

    Many animals are able to perceive the earth magnetic field and to use it for orientation and navigation within the environment. The mechanisms underlying the perception and processing of magnetic field information within the brain have been thoroughly studied, especially in birds, but are still obscure. Three hypotheses are currently discussed, dealing with ferromagnetic particles in the beak of birds, with the same sort of particles within the lagena organs, or describing magnetically influenced radical-pair processes within retinal photopigments. Each hypothesis is related to a well-known sensory organ and claims parallel processing of magnetic field information with somatosensory, vestibular and visual input, respectively. Changes in activation within nuclei of the respective sensory systems have been shown previously. Most of these previous experiments employed intensity enhanced magnetic stimuli or lesions. We here exposed unrestrained zebra finches to either a stationary or a rotating magnetic field of the local intensity and inclination. C-Fos was used as an activity marker to examine whether the two treatments led to differences in fourteen brain areas including nuclei of the somatosensory, vestibular and visual system. An ANOVA revealed an overall effect of treatment, indicating that the magnetic field change was perceived by the birds. While the differences were too small to be significant in most areas, a significant enhancement of activation by the rotating stimulus was found in a hippocampal subdivision. Part of the hyperpallium showed a strong, nearly significant, increase. Our results are compatible with previous studies demonstrating an involvement of at least three different sensory systems in earth magnetic field perception and suggest that these systems, probably less elaborated, may also be found in nonmigrating birds.

  16. 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

  17. Comparison of ADC map with trace map in the normal and infarct areas of the brains of stroke patients

    International Nuclear Information System (INIS)

    Kim, Seung Hyung; Yoon, Pyeong Ho; Jeong, Eun Kee; Oh, Young Taick; Kim, Dong Ik

    1999-01-01

    To compare ADC mapping with trace mapping in normal and infarct areas of the brains of stroke patients. Eighteen patients diagnosed on the basis of clinical and brain MRI examinations as suffering from brain infarction were included in this study (hyperacute-1, acute-4, subacute-12, chronic-1). Diffusion weighted images of three orthogonal directions of a patient's brain were obtained by means of a single shot EPI pulse sequence, using a diffusion gradient with four serial b-factors. Three ADC maps were then reconstructed by post-image processing and were summed pixel by pixel to yield a trace map. ROIs were selected in the normal areas of white matter, gray matter and CSF of one hemisphere, and other ROIs of the same size were selected at the same site of the contralateral hemisphere. ADC and trace values were measured and right/left ratios of ADC and trace values were calculated. Using these values, we then compared the ADC map with the trace map, and compared the degree of anisotropic diffusion between white matter, gray matter and CSF. Except for three, whose infarct lesions were small and lay over white and gray matter, patients were divided into two groups. Those with infarct in the white matter (n=10) were assigned to one group, and those with infarct in the gray matter (n=5) to the other. ROIs were selected in the infarct area and other ROIs of the same size were selected at the same site of the contralateral hemisphere. ADC and trace values were measured and infarct/contralateral ratios were calculated. We then compared ADC ratio with trace ratio in white matter and gray matter infarct. In normal white matter, the Dxx ratio was 0.980±0.098, the Dyy ratio 1.019±0.086, the Dzz ratio 0.999±0.111, and the trace ratio 0.995±0.031. In normal gray matter, the Dxx ratio was 1.001±0.058, the Dyy ratio 0.996±0.063, Dzz ratio 1.005±0.070, and the trace ratio 1.001±0.028. In CSF, the Dxx ratio was 1.002±0.064, the Dyy ratio 1.023±0.055, the Dzz ratio 0.999

  18. Accuracy of magnetic resonance based susceptibility measurements

    Science.gov (United States)

    Erdevig, Hannah E.; Russek, Stephen E.; Carnicka, Slavka; Stupic, Karl F.; Keenan, Kathryn E.

    2017-05-01

    Magnetic Resonance Imaging (MRI) is increasingly used to map the magnetic susceptibility of tissue to identify cerebral microbleeds associated with traumatic brain injury and pathological iron deposits associated with neurodegenerative diseases such as Parkinson's and Alzheimer's disease. Accurate measurements of susceptibility are important for determining oxygen and iron content in blood vessels and brain tissue for use in noninvasive clinical diagnosis and treatment assessments. Induced magnetic fields with amplitude on the order of 100 nT, can be detected using MRI phase images. The induced field distributions can then be inverted to obtain quantitative susceptibility maps. The focus of this research was to determine the accuracy of MRI-based susceptibility measurements using simple phantom geometries and to compare the susceptibility measurements with magnetometry measurements where SI-traceable standards are available. The susceptibilities of paramagnetic salt solutions in cylindrical containers were measured as a function of orientation relative to the static MRI field. The observed induced fields as a function of orientation of the cylinder were in good agreement with simple models. The MRI susceptibility measurements were compared with SQUID magnetometry using NIST-traceable standards. MRI can accurately measure relative magnetic susceptibilities while SQUID magnetometry measures absolute magnetic susceptibility. Given the accuracy of moment measurements of tissue mimicking samples, and the need to look at small differences in tissue properties, the use of existing NIST standard reference materials to calibrate MRI reference structures is problematic and better reference materials are required.

  19. In psychopathic patients emotion attribution modulates activity in outcome-related brain areas.

    Science.gov (United States)

    Sommer, Monika; Sodian, Beate; Döhnel, Katrin; Schwerdtner, Johannes; Meinhardt, Jörg; Hajak, Göran

    2010-05-30

    The understanding that other people's emotional states depend on the fulfilment of their intention is fundamentally important for responding adequately to others. Psychopathic patients show severe deficits in responding adequately to other people's emotion. The present study explored whether these impairments are associated with deficits in the ability to infer others' emotional states. Using functional magnetic resonance imaging (fMRI), identical cartoon stories, depicting a subject whose intention was fulfilled or not fulfilled, were presented to 14 psychopathic patients and 14 non-psychopathic patients. The participants should indicate the protagonist's emotional state. Additionally, a non-mentalizing control condition was presented. The two groups showed no behavioural differences. But in non-psychopathic patients emotion attribution was associated with increased activity of the mirror neuron system, the bilateral supramarginal gyrus and the superior frontal gyrus. In contrast psychopathic patients showed increased activation of regions associated with outcome monitoring and attention, such as the orbitofrontal cortex, the medial frontal cortex and temporo-parietal areas. The results emphasize that although psychopathic patients show no deficits in reasoning about other people's emotion if an explicit evaluation is demanded, they use divergent neural processing strategies that are related to more rational, outcome-oriented processes. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

  20. Regulation of Brain-Derived Neurotrophic Factor Exocytosis and Gamma-Aminobutyric Acidergic Interneuron Synapse by the Schizophrenia Susceptibility Gene Dysbindin-1.

    Science.gov (United States)

    Yuan, Qiang; Yang, Feng; Xiao, Yixin; Tan, Shawn; Husain, Nilofer; Ren, Ming; Hu, Zhonghua; Martinowich, Keri; Ng, Julia S; Kim, Paul J; Han, Weiping; Nagata, Koh-Ichi; Weinberger, Daniel R; Je, H Shawn

    2016-08-15

    Genetic variations in dystrobrevin binding protein 1 (DTNBP1 or dysbindin-1) have been implicated as risk factors in the pathogenesis of schizophrenia. The encoded protein dysbindin-1 functions in the regulation of synaptic activity and synapse development. Intriguingly, a loss of function mutation in Dtnbp1 in mice disrupted both glutamatergic and gamma-aminobutyric acidergic transmission in the cerebral cortex; pyramidal neurons displayed enhanced excitability due to reductions in inhibitory synaptic inputs. However, the mechanism by which reduced dysbindin-1 activity causes inhibitory synaptic deficits remains unknown. We investigated the role of dysbindin-1 in the exocytosis of brain-derived neurotrophic factor (BDNF) from cortical excitatory neurons, organotypic brain slices, and acute slices from dysbindin-1 mutant mice and determined how this change in BDNF exocytosis transsynaptically affected the number of inhibitory synapses formed on excitatory neurons via whole-cell recordings, immunohistochemistry, and live-cell imaging using total internal reflection fluorescence microscopy. A decrease in dysbindin-1 reduces the exocytosis of BDNF from cortical excitatory neurons, and this reduction in BDNF exocytosis transsynaptically resulted in reduced inhibitory synapse numbers formed on excitatory neurons. Furthermore, application of exogenous BDNF rescued the inhibitory synaptic deficits caused by the reduced dysbindin-1 level in both cultured cortical neurons and slice cultures. Taken together, our results demonstrate that these two genes linked to risk for schizophrenia (BDNF and dysbindin-1) function together to regulate interneuron development and cortical network activity. This evidence supports the investigation of the association between dysbindin-1 and BDNF in humans with schizophrenia. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  1. Study on cognition disorder and morphologic change of neurons in hippocampus area following traumatic brain injury in rats

    Institute of Scientific and Technical Information of China (English)

    洪军; 崔建忠; 周云涛; 高俊玲

    2002-01-01

    Objective: To explore the correlation between cognition disorder and morphologic change of hippocampal neurons after traumatic brain injury (TBI).   Methods: Wistar rat models with severe TBI were made by Marmarous method. The histopathological change of the neurons in the hippocampus area were studied with hematoxylin-eosin (HE) staining and terminal deoxynucleotidyl transferase-mediated X-dUPT nick end labeling (TUNEL), respectively. The cognitive function was evaluated with the Morris water maze test.   Results: The comprehensive neuronal degeneration and necrosis could be observed in CA2-3 regions of hippocampus at 3 days after injury. Apoptotic positive neurons in CA2-4 regions of hippocampus and dentate gyrus increased in the injured group at 24 hours following TBI. They peaked at 7 days and then declined. Significant impairment of spatial learning and memory was observed after injury in the rats.   Conclusions: The rats have obvious disorders in spatial learning and memory after severe TBI. Meanwhile, delayed neuronal necrosis and apoptosis can be observed in the neurons in the hippocampus area. It suggests that delayed hippocampal cell death may contribute to the functional deficit.

  2. Addressing the selective role of distinct prefrontal areas in response suppression: A study with brain tumor patients.

    Science.gov (United States)

    Arbula, Sandra; Pacella, Valentina; De Pellegrin, Serena; Rossetto, Marta; Denaro, Luca; D'Avella, Domenico; Della Puppa, Alessandro; Vallesi, Antonino

    2017-06-01

    The diverging evidence for functional localization of response inhibition within the prefrontal cortex might be justified by the still unclear involvement of other intrinsically related cognitive processes like response selection and sustained attention. In this study, the main aim was to understand whether inhibitory impairments, previously found in patients with both left and right frontal lesions, could be better accounted for by assessing these potentially related cognitive processes. We tested 37 brain tumor patients with left prefrontal, right prefrontal and non-prefrontal lesions and a healthy control group on Go/No-Go and Foreperiod tasks. In both types of tasks inhibitory impairments are likely to cause false alarms, although additionally the former task requires response selection and the latter target detection abilities. Irrespective of the task context, patients with right prefrontal damage showed frequent Go and target omissions, probably due to sustained attention lapses. Left prefrontal patients, on the other hand, showed both Go and target omissions and high false alarm rates to No-Go and warning stimuli, suggesting a decisional rather than an inhibitory impairment. An exploratory whole-brain voxel-based lesion-symptom mapping analysis confirmed the association of left ventrolateral and dorsolateral prefrontal lesions with target discrimination failure, and right ventrolateral and medial prefrontal lesions with target detection failure. Results from this study show how left and right prefrontal areas, which previous research has linked to response inhibition, underlie broader cognitive control processes, particularly involved in response selection and target detection. Based on these findings, we suggest that successful inhibitory control relies on more than one functionally distinct process which, if assessed appropriately, might help us to better understand inhibitory impairments across different pathologies. Copyright © 2017 The Authors

  3. The Brain Activity in Brodmann Area 17: A Potential Bio-Marker to Predict Patient Responses to Antiepileptic Drugs.

    Directory of Open Access Journals (Sweden)

    Yida Hu

    Full Text Available In this study, we aimed to predict newly diagnosed patient responses to antiepileptic drugs (AEDs using resting-state functional magnetic resonance imaging tools to explore changes in spontaneous brain activity. We recruited 21 newly diagnosed epileptic patients, 8 drug-resistant (DR patients, 11 well-healed (WH patients, and 13 healthy controls. After a 12-month follow-up, 11 newly diagnosed epileptic patients who showed a poor response to AEDs were placed into the seizures uncontrolled (SUC group, while 10 patients were enrolled in the seizure-controlled (SC group. By calculating the amplitude of fractional low-frequency fluctuations (fALFF of blood oxygen level-dependent signals to measure brain activity during rest, we found that the SUC patients showed increased activity in the bilateral occipital lobe, particularly in the cuneus and lingual gyrus compared with the SC group and healthy controls. Interestingly, DR patients also showed increased activity in the identical cuneus and lingual gyrus regions, which comprise Brodmann's area 17 (BA17, compared with the SUC patients; however, these abnormalities were not observed in SC and WH patients. The receiver operating characteristic (ROC curves indicated that the fALFF value of BA17 could differentiate SUC patients from SC patients and healthy controls with sufficient sensitivity and specificity prior to the administration of medication. Functional connectivity analysis was subsequently performed to evaluate the difference in connectivity between BA17 and other brain regions in the SUC, SC and control groups. Regions nearby the cuneus and lingual gyrus were found positive connectivity increased changes or positive connectivity changes with BA17 in the SUC patients, while remarkably negative connectivity increased changes or positive connectivity decreased changes were found in the SC patients. Additionally, default mode network (DMN regions showed negative connectivity increased changes or

  4. Effects of thyroid status on NEI concentration in specific brain areas related to reproduction during the estrous cycle.

    Science.gov (United States)

    Ayala, Carolina; Pennacchio, Gisela Erika; Soaje, Marta; Carreño, Norma Beatriz; Bittencourt, Jakson Cioni; Jahn, Graciela Alma; Celis, María Ester; Valdez, Susana Ruth

    2013-11-01

    We previously showed that short-term hypo- and hyperthyroidism induce changes in neuropeptide glutamic-acid-isoleucine-amide (NEI) concentrations in discrete brain areas in male rats. To investigate the possible effects of hypo- and hyperthyroidism on NEI concentrations mainly in hypothalamic areas related to reproduction and behavior, female rats were sacrificed at different days of the estrous cycle. Circulating luteinizing hormone (LH), estradiol and progesterone concentrations were measured in control, hypothyroid (hypoT, treated with PTU during 7-9 days) and hyperthyroid (hyperT, l-T4 during 4-7 days) animals. Both treatments blunted the LH surge. Hypo- and hyperthyroidism increased estradiol concentrations during proestrus afternoon (P-PM), although hypoT rats showed lower values compared to control during proestrus morning (P-AM). Progesterone levels were higher in all groups at P-PM and in the hyperT during diestrus morning (D2). NEI concentrations were lower in hypoT rats during the estrous cycle except in estrus (E) in the peduncular part of the lateral hypothalamus (PLH). They were also reduced by both treatments in the perifornical part of the lateral hypothalamus (PeFLH) during P-PM. Hypothyroidism led to higher NEI concentrations during P-PM in the organum vasculosum of the lamina terminalis and anteroventral periventricular nucleus (OVLT+AVPV). The present results indicate that NEI concentration is regulated in a complex manner by hypo- and hyperthyroidism in the different areas studied, suggesting a correlation between NEI values and the variations of gonadal steroid levels during estrous cycle. These changes could be, in part, responsible for the alterations observed in the hypothalamic-pituitary-gonadal axis in these pathologies. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Mapping the areas sensitive to long-term endotoxin tolerance in the rat brain: a c-fos mRNA study.

    Science.gov (United States)

    Vallès, Astrid; Martí, Octavi; Armario, Antonio

    2005-06-01

    We have recently found that a single endotoxin administration to rats reduced the hypothalamic-pituitary-adrenal response to another endotoxin administration 4 weeks later, which may be an example of the well-known phenomenon of endotoxin tolerance. However, the time elapsed between the two doses of endotoxin was long enough to consider the above results as an example of late tolerance, whose mechanisms are poorly characterized. To know if the brain plays a role in this phenomenon and to characterize the putative areas involved, we compared the c-fos mRNA response after a final dose of endotoxin in animals given vehicle or endotoxin 4 weeks before. Endotoxin caused a widespread induction of c-fos mRNA in the brain, similar to that previously reported by other laboratories. Whereas most of the brain areas were not sensitive to the previous experience with endotoxin, a few showed a reduced response in endotoxin-pretreated rats: the parvocellular and magnocellular regions of the paraventricular hypothalamic nucleus, the central amygdala, the lateral division of the bed nucleus and the locus coeruleus. We hypothesize that late tolerance to endotoxin may involve plastic changes in the brain, likely to be located in the central amygdala. The reduced activation of the central amygdala in rats previously treated with endotoxin may, in turn, reduce the activation of other brain areas, including the hypothalamic paraventicular nucleus.

  6. Cortical thickness, surface area, and volume of the brain reward system in alcohol dependence: relationships to relapse and extended abstinence.

    Science.gov (United States)

    Durazzo, Timothy C; Tosun, Duygu; Buckley, Shannon; Gazdzinski, Stefan; Mon, Anderson; Fryer, Susanna L; Meyerhoff, Dieter J

    2011-06-01

    At least 60% of those treated for an alcohol use disorder will relapse. Empirical study of the integrity of the brain reward system (BRS) is critical to understanding the mechanisms of relapse as this collection of circuits is implicated in the development and maintenance of all forms of addictive disorders. This study compared thickness, surface area, and volume in neocortical components of the BRS among nonsmoking light-drinking controls (controls), individuals who remained abstinent and those who relapsed after treatment. Seventy-five treatment-seeking alcohol-dependent individuals (abstinent for 7±3 days) and 43 controls completed 1.5T proton magnetic resonance imaging studies. Parcellated morphological data were obtained for following bilateral components of the BRS: rostral and caudal anterior cingulate cortex, insula, medial and lateral orbitofrontal cortex (OFC), rostral and caudal middle and superior frontal gyri, amygdala and hippocampus as well as for 26 other bilateral neocortical regions. Alcohol-dependent participants were followed over 12-months after baseline study and were classified as abstainers (no alcohol consumption; n=24) and relapsers (any alcohol consumption; n=51) at follow-up. Relapsers and abstainers demonstrated lower cortical thickness in the vast majority of BRS regions as well as lower global thickness compared to controls. Relapsers had lower total BRS surface area than both controls and abstainers, but abstainers were not significantly different from controls on any surface area measure. Relapsers demonstrated lower volumes than controls in the majority of regions, while abstainers showed lower volumes than controls in the superior frontal gyrus, insula, amygdala, and hippocampus, bilaterally. Relapsers exhibited smaller volumes than abstainers in the right rostral middle and caudal middle frontal gyri and the lateral OFC, bilaterally. In relapsers, lower baseline volumes and surface areas in multiple regions were associated with

  7. Human cerebral blood volume measurements using dynamic contrast enhancement in comparison to dynamic susceptibility contrast MRI

    Energy Technology Data Exchange (ETDEWEB)

    Artzi, Moran [Tel Aviv Sourasky Medical Center, Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv (Israel); Tel Aviv University, Sackler Faculty of Medicine, Tel Aviv (Israel); Liberman, Gilad; Vitinshtein, Faina; Aizenstein, Orna [Tel Aviv Sourasky Medical Center, Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv (Israel); Nadav, Guy [Tel Aviv Sourasky Medical Center, Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv (Israel); Tel Aviv University, Faculty of Engineering, Tel Aviv (Israel); Blumenthal, Deborah T.; Bokstein, Felix [Tel Aviv Sourasky Medical Center, Neuro-Oncology Service, Tel Aviv (Israel); Bashat, Dafna Ben [Tel Aviv Sourasky Medical Center, Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv (Israel); Tel Aviv University, Sackler Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv (Israel)

    2015-07-15

    Cerebral blood volume (CBV) is an important parameter for the assessment of brain tumors, usually obtained using dynamic susceptibility contrast (DSC) MRI. However, this method often suffers from low spatial resolution and high sensitivity to susceptibility artifacts and usually does not take into account the effect of tissue permeability. The plasma volume (v{sub p}) can also be extracted from dynamic contrast enhancement (DCE) MRI. The aim of this study was to investigate whether DCE can be used for the measurement of cerebral blood volume in place of DSC for the assessment of patients with brain tumors. Twenty-eight subjects (17 healthy subjects and 11 patients with glioblastoma) were scanned using DCE and DSC. v{sub p} and CBV values were measured and compared in different brain components in healthy subjects and in the tumor area in patients. Significant high correlations were detected between v{sub p} and CBV in healthy subjects in the different brain components; white matter, gray matter, and arteries, correlating with the known increased tissue vascularity, and within the tumor area in patients. This work proposes the use of DCE as an alternative method to DSC for the assessment of blood volume, given the advantages of its higher spatial resolution, its lower sensitivity to susceptibility artifacts, and its ability to provide additional information regarding tissue permeability. (orig.)

  8. Novel Middle-Type Kenyon Cells in the Honeybee Brain Revealed by Area-Preferential Gene Expression Analysis

    OpenAIRE

    Kaneko, Kumi; Ikeda, Tsubomi; Nagai, Mirai; Hori, Sayaka; Umatani, Chie; Tadano, Hiroto; Ugajin, Atsushi; Nakaoka, Takayoshi; Paul, Rajib Kumar; Fujiyuki, Tomoko; Shirai, Kenichi; Kunieda, Takekazu; Takeuchi, Hideaki; Kubo, Takeo

    2013-01-01

    The mushroom bodies (a higher center) of the honeybee (Apis mellifera L) brain were considered to comprise three types of intrinsic neurons, including large- and small-type Kenyon cells that have distinct gene expression profiles. Although previous neural activity mapping using the immediate early gene kakusei suggested that small-type Kenyon cells are mainly active in forager brains, the precise Kenyon cell types that are active in the forager brain remain to be elucidated. We searched for n...

  9. Sexual dimorphism of Broca's region: More gray matter in female brains in Brodmann areas 44 and 45.

    Science.gov (United States)

    Kurth, Florian; Jancke, Lutz; Luders, Eileen

    2017-01-02

    Although a sexual dimorphism in brain structure is generally well established, evidence for sex differences in Brodmann areas (BA) 44 and 45 is inconclusive. This may be due to the difficulty of accurately defining BA 44 and BA 45 in magnetic resonance images, given that these regions are variable in their location and extent and that they do not match well with macroanatomic landmarks. Here we set out to test for possible sex differences in the local gray matter of BA 44/45 by integrating imaging-based signal intensities with cytoarchitectonically defined tissue probabilities in a sample of 50 male and 50 female subjects. In addition to testing for sex differences with respect to left- and right-hemispheric measures of BA 44/45, we also assessed possible sex differences in BA 44/45 asymmetry. Our analyses revealed significantly larger gray matter volumes in females compared with males for BA 44 and BA 45 bilaterally. However, there was a lack of significant sex differences in BA 44/45 asymmetry. These results corroborate reports of a language-related female superiority, particularly with respect to verbal fluency and verbal memory tasks. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  10. Evolving Concepts in Posterior Subthalamic Area Deep Brain Stimulation for Treatment of Tremor: Surgical Neuroanatomy and Practical Considerations.

    Science.gov (United States)

    Ramirez-Zamora, Adolfo; Smith, Heather; Kumar, Vignessh; Prusik, Julia; Phookan, Sujoy; Pilitsis, Julie G

    2016-01-01

    Although thalamic deep brain stimulation (DBS) has been established as an effective therapy for refractory tremor in Parkinson's disease and essential tremor, reports investigating the efficacy of posterior subthalamic area (PSA) DBS for severe, debilitating tremors continue to emerge. However, questions regarding the optimal anatomical target, surgical approach, programming paradigms and effectiveness compared to other targets remain. In this report, we aimed to review the current literature to assess different stereotactic techniques, anatomical considerations, adverse effects and stimulation settings in PSA DBS. A comprehensive literature review was performed searching for articles discussing tremors and PSA stimulation. We performed a quantitative analysis comparing different DBS tremor targets. Tremor improvement is consistently documented in most reports with an average reduction in tremor of 79% depending on the specific tremor syndrome. Tremor benefit in patients with multiple sclerosis (MS) tremor was significantly higher than for other stimulation targets. Transient paresthesias, imbalance, dizziness and dysarthria are the most common side effects with PSA DBS. PSA DBS is an effective and safe treatment for tremor control and should be considered in patients with refractory tremors with associated cerebellar or dystonic features, proximal tremors and MS tremor. © 2016 S. Karger AG, Basel.

  11. Accuracy and reproducibility of simple cross-sectional linear and area measurements of brain structures and their comparison with volume measurements

    International Nuclear Information System (INIS)

    Whalley, H.C.; Wardlaw, J.M.

    2001-01-01

    Volumetric measurement of brain structure on brain images is regarded as a gold standard, yet is very time consuming. We wondered whether simple linear and area measurements might be as accurate and reproducible. Two observers independently measured the cross-sectional area of the corpus callosum, lentiform and caudate nuclei, thalamus, amygdalas, hippocampi, lateral and third ventricles, and the width of the sylvian and frontal interhemispheric fissures and brain stem on brain MRI of 55 patients using a program written in-house; one observer also measured the volumes of the basal ganglia, amygdalo-hippocampal complex and ventricular system using Analyze, and performed qualitative assessment of four regions (lateral and third ventricles, cortex, and medial temporal lobe) using the Lieberman score. All measures were performed blinded to all other information. Test objects of known size were also imaged with MRI and measured by the two observers using the in-house program. The true sizes of the test objects were measured using engineering calipers by two observers blind to the MRI results. Differences between the two observers using the same measurement method, and one observer using different methods, were calculated. The simple linear and cross-sectional area measurements were rapid (20 min versus 5 h for volumetric); were highly accurate for test-object measurement versus true size; had excellent intraobserver reliability; and, for most brain structures, the simple measures correlated highly significantly with volumetric measures. The simple measures were in general highly reproducible, the difference (as a percentage of the area or width of a region) between the two raters being around 10 %, range 0.1 %- 14.1 %, (similar to inter-rater variability in previous studies of volume measurements). The simple linear and area measures are reproducible and correlate well with the measured volumes, and there is a considerable time saving with the former. In circumstances

  12. Determining Earthquake Susceptible Areas Southeast of Yogyakarta, Indonesia—Outcrop Analysis from Structure from Motion (SfM and Geographic Information System (GIS

    Directory of Open Access Journals (Sweden)

    Aditya Saputra

    2018-04-01

    Full Text Available Located approximately a hundred kilometres north of Java Subduction Zone, Java Island has a complicated geology and geomorphology. The north zone is dominated by the folded area, the centre is dominated by the active volcanic arc and the south of Java including the study area (Southeast part of Yogyakarta City, is dominated by the uplifted southern mountain. In general, the study area is part of the Bantul’s Graben. In the middle part of study area flows the Opak River, which is often associated with normal faults of Opak Fault. The Opak Fault is such a complex fault system which has a complex local fault which can cause worst local site effect when earthquakes occur. However, the geology map of Yogyakarta is the only data that gives the characteristics of Opak Fault roughly. Thus, the effort to identify unchartered fault system needs to be done. The aims of this study are to conduct the outcrop study, to identify the micro faults and to improve the understanding of faults system to support the earthquake hazard and risk assessment. The integrated method of remote sensing, structure from motion (SfM, geographic information system (GIS and direct outcrop observation was conducted in the study area. Remote sensing was applied to recognize the outcrop location and to extract the nature lineament feature which can be used as fault indicator. The structure from motion was used to support characterising the outcrop in the field, to identify the fault evidence, and to measure the fault displacement on the outcrops. The direct outcrop observation is very useful to reveal the lithofacies characteristics and to reconstruct the lithostratigraphic correlation among the outcrops. Meanwhile, GIS was used to analyse all the data from remote sensing, SfM, and direct outcrop observation. The main findings of this study were as follows: the middle part of study area has the most complicated geologic structure. At least 56 faults evidence with the maximum

  13. Distribution of the insecticide 14 C-fen valerate and its effect on protein and amino acid content in different brain areas of the rat

    International Nuclear Information System (INIS)

    Aly, M.A.S.

    1998-01-01

    Intragastric administration of fenvalerate (45 mg/kg) to male rats induced symptoms associated with gamma-cyano pyrethroids (type II syndrome). Fenvalerate crossed blood brain barrier and reached different brain areas. The highest concentration of fenvalerate was found in striatum (18.7+2.5 Mou/g) followed by pons + medulla oblongata (10.4+ 0.91Moug/g) after 24 h of the insecticide administration. A decrease in the protein content in different brain areas was recorded at 24 h. However, it was observed that there was a tendency for the protein level to recover at 48 h although it was still lower than corresponding controlgroup. Excitatory neurotransmitter amino acids, glutamic and aspartic, in the pons + medulla oblongata showed a prominent decrease (-9.9 and 7.0%, respectively). Inhibitory neurotransmitter amino acids, glycine and alanine, showed a slight decrease. On the other hand, the amino acids in the striatum revealed fluctuating changes. Amino acids acting as a precursor of neurotransmitter were also affected in the selected brain areas. The data obtained revealed that fenvalerate caused subtle disruption in the integrity of the CNS and there is a possibility that such disruption might result in physiological and behavioural alteration which may affect the organism ability to interact with environment

  14. Assessment of the brain areas perfused by superselective intra-arterial chemotherapy using single photon emission computed tomography with technetium-99m-hexamethyl-propyleneamine oxime. Technical note

    Energy Technology Data Exchange (ETDEWEB)

    Namba, Hiroki; Iwadate, Yasuo; Saegusa, Takashi; Sueyoshi, Kanji [Chiba Cancer Center Hospital (Japan); Kobayashi, Shigeki; Sato, Akira; Watanabe, Yoshiro

    1994-12-01

    The brain areas perfused by superselective intra-arterial (i.a.) chemotherapy were assessed using single photon emission computed tomography (SPECT) with technetium-99m-hexamethyl-propyleneamine oxime ({sup 99m}Tc-HMPAO). A superselective catheter was introduced into the anterior, middle, or posterior cerebral artery of patients with malignant glioma for i.a. chemotherapy. {sup 99m}Tc-HMPAO was subsequently injected via the same catheter used for chemotherapy, and a higher dose of {sup 99m}Tc-HMPAO was injected intravenously to obtain adequate background brain images. Comparison of the SPECT images with magnetic resonance images could confirm complete perfusion of the tumor tissue. In two patients with malignant glioma, regions of interest were selected in the peritumoral brain area and a reference brain area, and the radioactivity was measured. The concentration of {sup 99m}Tc-HMPAO was about 50 times higher in tissue perfused by superselective injection into anterior or middle cerebral artery compared to intravenous injection. {sup 99m}Tc-HMPAO SPECT is readily available in many institutions and the information provided is useful for planning more effective and safe i.a. chemotherapy. (author).

  15. Evaluation of brain perfusion in specific Brodmann areas in Frontotemporal dementia and Alzheimer disease using automated 3-D voxel based analysis

    Energy Technology Data Exchange (ETDEWEB)

    Valotassiou, V; Tsougos, I; Tzavara, C; Georgoulias, P [Nuclear Medicine Dpt, University Hospital of Larissa, Larissa (Greece); Papatriantafyllou, J; Karageorgiou, C [Neurology Dpt, General Hospital ' G. Gennimatas' , Athens (Greece); Sifakis, N; Zerva, C [Nuclear Medicine Dpt, ' Alexandra' University Hospital, Athens (Greece)], E-mail: vanvalot@yahoo.gr

    2009-05-15

    Introduction. Brain perfusion studies with single-photon emission computed tomography (SPECT) have been applied in demented patients to provide better discrimination between frontotemporal dementia (FTD) and Alzheimer's disease (AD). Aim. To assess the perfusion of specific Brodmann (Br) areas of the brain cortex in FTD and AD patients, using NeuroGam processing program to provide 3D voxel-by-voxel cerebral SPECT analysis. Material and methods. We studied 34 consecutive patients. We used the established criteria for the diagnosis of dementia and the specific established criteria for the diagnosis of FTD and AD. All the patients had a neuropsychological evaluation with a battery of tests including the mini-mental state examination (MMSE).Twenty-six patients (16 males, 10 females, mean age 68.76{+-}6.51 years, education 11.81{+-}4.25 years, MMSE 16.69{+-}9.89) received the diagnosis of FTD and 8 patients (all females, mean age 71.25{+-}10.48 years, education 10{+-}4.6 years, MMSE 12.5{+-}3.89) the diagnosis of AD. All the patients underwent a brain SPECT. We applied the NeuroGam Software for the evaluation of brain perfusion in specific Br areas in the left (L) and right (R) hemispheres. Results. Statistically significant hypoperfusion in FTD compared to AD patients, was found in the following Br areas: 11L (p<0.0001), 11R, 20L, 20R, 32L, 38L, 38R, 44L (p<0.001), 32R, 36L, 36R, 45L, 45R, 47R (p<0.01), 9L, 21L, 39R, 44R, 46R, 47L (p<0.05). On the contrary, AD patients presented significant (p<0.05) hypoperfusion in 7R and 39R Br areas. Conclusion. NeuroGam processing program of brain perfusion SPECT could result in enhanced accuracy for the differential diagnosis between AD and FTD patients.

  16. The cooperation of the functional activation areas in human brain: an application of event-related fMRI study of the voluntary motor function

    International Nuclear Information System (INIS)

    Li Enzhong; Tian Jie; Dai Ruwei

    2002-01-01

    Objective: To detect the cooperation of the functional activation areas in human brain using event-related fMRI technique developed in recent years. Methods: Forty-four subjects were selected in this experiment and scanned by GE Signa Horizon 1.5 Tesla superconductive MR system. A CUE-GO paradigm was used in this experiment. The data were analyzed in SUN and SGI workstation. Results: The activation areas were found in contralateral primary motor area (Ml), bilateral supplementary motor areas (SMA), pre-motor areas (PMA), basal ganglia, and cerebellar cortices. The time-signal curve of Ml was a typical single-peak curve, but the curves in PMA, basal ganglia, and cerebellar cortices were double-peak curves. SMA had 2 parts, one was Pre-SMA, and another was SMA Proper. The curve was double-peak type in Pre-SMA and single-peak type in SMA Proper. There was difference between the time-signal intensity curves in above-mentioned areas. Conclusion: (1) Ml is mainly associated with motor execution, while others with both motor preparation and execution. There are differences in the function at the variant areas in the brain. (2) The fact that bilateral SMA, PMA, basal ganglia, and cerebellar cortices were activated, is different from what the classical theories told. (3) Event-related fMRI technique has higher temporary and spatial resolutions. (4) There is cooperation among different cortical areas, basal ganglia, and cerebellum

  17. Brain surface anatomy in adults with autism: the relationship between surface area, cortical thickness, and autistic symptoms.

    Science.gov (United States)

    Ecker, Christine; Ginestet, Cedric; Feng, Yue; Johnston, Patrick; Lombardo, Michael V; Lai, Meng-Chuan; Suckling, John; Palaniyappan, Lena; Daly, Eileen; Murphy, Clodagh M; Williams, Steven C; Bullmore, Edward T; Baron-Cohen, Simon; Brammer, Michael; Murphy, Declan G M

    2013-01-01

    Neuroimaging studies of brain anatomy in autism spectrum disorder (ASD) have mostly been based on measures of cortical volume (CV). However, CV is a product of 2 distinct parameters, cortical thickness (CT) and surface area (SA), that in turn have distinct genetic and developmental origins. To investigate regional differences in CV, SA, and CT as well as their relationship in a large and well-characterized sample of men with ASD and matched controls. Multicenter case-control design using quantitative magnetic resonance imaging. Medical Research Council UK Autism Imaging Multicentre Study. A total of 168 men, 84 diagnosed as having ASD and 84 controls who did not differ significantly in mean (SD) age (26 [7] years vs 28 [6] years, respectively) or full-scale IQ (110 [14] vs 114 [12], respectively). Between-group differences in CV, SA, and CT investigated using a spatially unbiased vertex-based approach; the degree of spatial overlap between the differences in CT and SA; and their relative contribution to differences in regional CV. Individuals with ASD differed from controls in all 3 parameters. These mainly consisted of significantly increased CT within frontal lobe regions and reduced SA in the orbitofrontal cortex and posterior cingulum. These differences in CT and SA were paralleled by commensurate differences in CV. The spatially distributed patterns for CT and SA were largely nonoverlapping and shared only about 3% of all significantly different locations on the cerebral surface. Individuals with ASD have significant differences in CV, but these may be underpinned by (separable) variations in its 2 components, CT and SA. This is of importance because both measures result from distinct developmental pathways that are likely modulated by different neurobiological mechanisms. This finding may provide novel targets for future studies into the etiology of the condition and a new way to fractionate the disorder.

  18. Differential behavioral profile induced by the injection of dipotassium chlorazepate within brain areas that project to the nucleus accumbens septi.

    Science.gov (United States)

    Llano López, Luis H; Caif, Fernando; Fraile, Miriam; Tinnirello, Belén; de Gargiulo, Adriana I Landa; Lafuente, José V; Baiardi, Gustavo C; Gargiulo, Pascual A

    2013-01-01

    The effect of the agonism on γ-aminobutyric acid (GABA) receptors was studied within medial prefrontal cortex (mPFC), amygdala (AMY) and ventral hipocampus (VH) in the plus-maze test in male rats bilaterally cannulated. These structures send glutamatergic projections to the nucleus accumbens septi (NAS), in which interaction and integration between these afferent pathways has been described. In a previous study of our group, blockade of glutamatergic transmission within NAS induced an anxiolytic like effect. Three rat groups received either saline or dipotassium chlorazepate (1 or 2 μg/1 μl solution) 15 min before testing. Time spent in the open arms (TSOA), time per entry (TPE), extreme arrivals (EA), open and closed arms entries (OAE, CAE) and relationship between open- and closed-arms quotient (OCAQ) were recorded. In the AMY injected group TSOA, OAE and EA were increased by the higher doses of dipotassium chlorazepate (p < 0.01). In the mPFC, TPE was decreased by both doses (p < 0.05). Injection within ventral hippocampus (VH) decreased TSOA, OAE and OCAQ with lower doses (p < 0.05). When the three studied saline groups were compared, TSOA, OAE, EA and OCAQ were enhanced in the VH group when compared to mPFC and AMY (p < 0.001). Insertion of inner canula (p < 0.001, p < 0.01, p < 0.01) and saline injection showed an increasing significant difference (p < 0.001 in all cases) with the action of guide cannula alone within VH in TSOA, OAE and EA. We conclude that the injection of dipotassium chlorazepate has a differential effect depending of the brain area, leading to facilitatory and inhibitory effects on anxiety processing.

  19. Effects of insulin and leptin in the ventral tegmental area and arcuate hypothalamic nucleus on food intake and brain reward function in female rats.

    Science.gov (United States)

    Bruijnzeel, Adrie W; Corrie, Lu W; Rogers, Jessica A; Yamada, Hidetaka

    2011-06-01

    There is evidence for a role of insulin and leptin in food intake, but the effects of these adiposity signals on the brain reward system are not well understood. Furthermore, the effects of insulin and leptin on food intake in females are underinvestigated. These studies investigated the role of insulin and leptin in the ventral tegmental area (VTA) and the arcuate hypothalamic nucleus (Arc) on food intake and brain reward function in female rats. The intracranial self-stimulation procedure was used to assess the effects of insulin and leptin on the reward system. Elevations in brain reward thresholds are indicative of a decrease in brain reward function. The bilateral administration of leptin into the VTA (15-500 ng/side) or Arc (15-150 ng/side) decreased food intake for 72 h. The infusion of leptin into the VTA or Arc resulted in weight loss during the first 48 (VTA) or 24 h (Arc) after the infusions. The administration of insulin (0.005-5 mU/side) into the VTA or Arc decreased food intake for 24 h but did not affect body weights. The bilateral administration of low, but not high, doses of leptin (15 ng/side) or insulin (0.005 mU/side) into the VTA elevated brain reward thresholds. Neither insulin nor leptin in the Arc affected brain reward thresholds. These studies suggest that a small increase in leptin or insulin levels in the VTA leads to a decrease in brain reward function. A relatively large increase in insulin or leptin levels in the VTA or Arc decreases food intake. Published by Elsevier B.V.

  20. Synaesthetic Colour in the Brain: Beyond Colour Areas. A Functional Magnetic Resonance Imaging Study of Synaesthetes and Matched Controls

    NARCIS (Netherlands)

    Leeuwen, T.M. van; Petersson, K.M.; Hagoort, P.

    2010-01-01

    Background: In synaesthesia, sensations in a particular modality cause additional experiences in a second, unstimulated modality (e. g., letters elicit colour). Understanding how synaesthesia is mediated in the brain can help to understand normal processes of perceptual awareness and multisensory

  1. Holistic face categorization in higher-level cortical visual areas of the normal and prosopagnosic brain: towards a non-hierarchical view of face perception

    Directory of Open Access Journals (Sweden)

    Bruno Rossion

    2011-01-01

    Full Text Available How a visual stimulus is initially categorized as a face in a network of human brain areas remains largely unclear. Hierarchical neuro-computational models of face perception assume that the visual stimulus is first decomposed in local parts in lower order visual areas. These parts would then be combined into a global representation in higher order face-sensitive areas of the occipito-temporal cortex. Here we tested this view in fMRI with visual stimuli that are categorized as faces based on their global configuration rather than their local parts (2-tones Mooney figures and Arcimboldo’s facelike paintings. Compared to the same inverted visual stimuli that are not categorized as faces, these stimuli activated the right middle fusiform gyrus (Fusiform face area, FFA and superior temporal sulcus (pSTS, with no significant activation in the posteriorly located inferior occipital gyrus (i.e., no occipital face area, OFA. This observation is strengthened by behavioral and neural evidence for normal face categorization of these stimuli in a brain-damaged prosopagnosic patient (PS whose intact right middle fusiform gyrus and superior temporal sulcus are devoid of any potential face-sensitive inputs from the lesioned right inferior occipital cortex. Together, these observations indicate that face-preferential activation may emerge in higher order visual areas of the right hemisphere without any face-preferential inputs from lower order visual areas, supporting a non-hierarchical view of face perception in the visual cortex.

  2. Brain tumors and syndromes in children

    NARCIS (Netherlands)

    Bleeker, Fonnet E.; Hopman, Saskia M. J.; Merks, Johannes H. M.; Aalfs, Cora M.; Hennekam, Raoul C. M.

    2014-01-01

    (Brain) tumors are usually a disorder of aged individuals. If a brain tumor occurs in a child, there is a possible genetic susceptibility for this. Such genetic susceptibilities often show other signs and symptoms. Therefore, every child with a brain tumor should be carefully evaluated for the

  3. Organ distribution of quantum dots after intraperitoneal administration, with special reference to area-specific distribution in the brain

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Shingo; Itoh, Kyoko; Yaoi, Takeshi; Tozawa, Takenori; Fushiki, Shinji [Department of Pathology and Applied Neurobiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto (Japan); Yoshikawa, Yutaka; Yasui, Hiroyuki [Department of Analytical and Bioinorganic Chemistry, Kyoto Pharmaceutical University, Kyoto (Japan); Kanamura, Narisato [Department of Dental Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto (Japan); Hoshino, Akiyoshi; Manabe, Noriyoshi; Yamamoto, Kenji, E-mail: sfushiki@koto.kpu-m.ac.jp [The International Clinical Research Center, Research Institute, International Medical Center of Japan, Tokyo (Japan)

    2010-08-20

    Quantum dots (QDs) are well known for their potential application in biosensing, ex vivo live-cell imaging and in vivo animal targeting. The brain is a challenging organ for drug delivery, because the blood brain barrier (BBB) functions as a gatekeeper guarding the body from exogenous substances. Here, we evaluated the distribution of bioconjugated QDs, i.e., captopril-conjugated QDs (QDs-cap) following intraperitoneal injection into male ICR mice as a model system for determining the tissue localization of QDs, employing ICP-MS and confocal microscopy coupled with spectrometric analysis. We have demonstrated that intraperitoneally administered QDs-cap were delivered via systemic blood circulation into liver, spleen, kidney and brain at 6 h after injection. QDs-cap were located predominantly inside the blood vessels in the liver, kidney and brain, but a few were distributed in the parenchyma, especially noteworthy in the brain. Careful studies on acute as well as chronic toxicity of QDs in the brain are required prior to clinical application to humans.

  4. Organ distribution of quantum dots after intraperitoneal administration, with special reference to area-specific distribution in the brain

    International Nuclear Information System (INIS)

    Kato, Shingo; Itoh, Kyoko; Yaoi, Takeshi; Tozawa, Takenori; Fushiki, Shinji; Yoshikawa, Yutaka; Yasui, Hiroyuki; Kanamura, Narisato; Hoshino, Akiyoshi; Manabe, Noriyoshi; Yamamoto, Kenji

    2010-01-01

    Quantum dots (QDs) are well known for their potential application in biosensing, ex vivo live-cell imaging and in vivo animal targeting. The brain is a challenging organ for drug delivery, because the blood brain barrier (BBB) functions as a gatekeeper guarding the body from exogenous substances. Here, we evaluated the distribution of bioconjugated QDs, i.e., captopril-conjugated QDs (QDs-cap) following intraperitoneal injection into male ICR mice as a model system for determining the tissue localization of QDs, employing ICP-MS and confocal microscopy coupled with spectrometric analysis. We have demonstrated that intraperitoneally administered QDs-cap were delivered via systemic blood circulation into liver, spleen, kidney and brain at 6 h after injection. QDs-cap were located predominantly inside the blood vessels in the liver, kidney and brain, but a few were distributed in the parenchyma, especially noteworthy in the brain. Careful studies on acute as well as chronic toxicity of QDs in the brain are required prior to clinical application to humans.

  5. Acupuncture at Waiguan (SJ5) and sham points influences activation of functional brain areas of ischemic stroke patients: a functional magnetic resonance imaging study.

    Science.gov (United States)

    Qi, Ji; Chen, Junqi; Huang, Yong; Lai, Xinsheng; Tang, Chunzhi; Yang, Junjun; Chen, Hua; Qu, Shanshan

    2014-02-01

    Most studies addressing the specificity of meridians and acupuncture points have focused mainly on the different neural effects of acupuncture at different points in healthy individuals. This study examined the effects of acupuncture on brain function in a pathological context. Sixteen patients with ischemic stroke were randomly assigned to true point group (true acupuncture at right Waiguan (SJ5)) and sham point group (sham acupuncture). Results of functional magnetic resonance imaging revealed activation in right parietal lobe (Brodmann areas 7 and 19), the right temporal lobe (Brodmann area 39), the right limbic lobe (Brodmann area 23) and bilateral occipital lobes (Brodmann area 18). Furthermore, inhibition of bilateral frontal lobes (Brodmann area 4, 6, and 45), right parietal lobe (Brodmann areas 1 and 5) and left temporal lobe (Brodmann area 21) were observed in the true point group. Activation in the precuneus of right parietal lobe (Brodmann area 7) and inhibition of the left superior frontal gyrus (Brodmann area 10) was observed in the sham group. Compared with sham acupuncture, acupuncture at Waiguan in stroke patients inhibited Brodmann area 5 on the healthy side. Results indicated that the altered specificity of sensation-associated cortex (Brodmann area 5) is possibly associated with a central mechanism of acupuncture at Waiguan for stroke patients.

  6. Storm-Induced Slope Failure Susceptibility Mapping

    Science.gov (United States)

    2018-01-01

    A pilot study was conducted to characterize and map the areas susceptible to slope failure using state-wide available data. The objective was to determine whether it would be possible to provide slope-failure susceptibility mapping that could be used...

  7. Embedding filtering criteria into a wrapper marker selection method for brain tumor classification: an application on metabolic peak area ratios

    International Nuclear Information System (INIS)

    Kounelakis, M G; Zervakis, M E; Giakos, G C; Postma, G J; Buydens, L M C; Kotsiakis, X

    2011-01-01

    The purpose of this study is to identify reliable sets of metabolic markers that provide accurate classification of complex brain tumors and facilitate the process of clinical diagnosis. Several ratios of metabolites are tested alone or in combination with imaging markers. A wrapper feature selection and classification methodology is studied, employing Fisher's criterion for ranking the markers. The set of extracted markers that express statistical significance is further studied in terms of biological behavior with respect to the brain tumor type and grade. The outcome of this study indicates that the proposed method by exploiting the intrinsic properties of data can actually reveal reliable and biologically relevant sets of metabolic markers, which form an important adjunct toward a more accurate type and grade discrimination of complex brain tumors

  8. In vivo fate of a behaviorally potent ACTH 4-9 analog; evidence for its specific uptake in the brain septal area

    International Nuclear Information System (INIS)

    Verhoef, J.

    1977-01-01

    The effects of ACTH-like neuropeptides on conditioned avoidance behavior and their tentative central sites of action are reviewed. The in vivo fate of the [ 3 H]-ACTH 4-9 analog after various routes of peripheral administration in mice and rats are described, in particular, the uptake of intact peptide in the brain is emphasized, since ACTH-like neuropeptides elicit their behavioral activities by directly affecting the central nervous system. Subsequently, the metabolic profiles of the ACTH 4-9 analog in plasma and brain tissue are reported. The distribution of the [ 3 H]-ACTH 4-9 analog throughout the rat brain is studied after intraventricular injection to allow detection in small brain areas and nuclei and to limit (peripheral) proteolysis. Finally, the effects of increased and decreased circulating levels of both ACTH-like peptides and structurally non-related but behaviorally active neuropeptides on the central distribution profile of intraventricularly injected [ 3 H]-ACTH 4-9 analog are reviewed

  9. Synaesthetic colour in the brain: Beyond colour areas. A functional magnetic resonance imaging study of synaesthetes and matched controls

    NARCIS (Netherlands)

    van Leeuwen, T.M.; Petersson, K.M.; Hagoort, P.

    2010-01-01

    Background

    In synaesthesia, sensations in a particular modality cause additional experiences in a second, unstimulated modality (e.g., letters elicit colour). Understanding how synaesthesia is mediated in the brain can help to understand normal processes of perceptual

  10. Investigation into the prevalence and antibacterial susceptibility ...

    African Journals Online (AJOL)

    Investigation into the prevalence and antibacterial susceptibility patterns of aeromonas and plesiomonas species isolated from children with diarrhoea in Amuwo-Odofin and Surulere Local Government areas of Lagos, Nigeria.

  11. Sense and antisense transcripts of the developmentally regulated murine hsp70.2 gene are expressed in distinct and only partially overlapping areas in the adult brain

    Science.gov (United States)

    Murashov, A. K.; Wolgemuth, D. J.

    1996-01-01

    We have examined the spatial pattern of expression of a member of the hsp70 gene family, hsp70.2, in the mouse central nervous system. Surprisingly, RNA blot analysis and in situ hybridization revealed abundant expression of an 'antisense' hsp70.2 transcript in several areas of adult mouse brain. Two different transcripts recognized by sense and antisense riboprobes for the hsp70.2 gene were expressed in distinct and only partially overlapping neuronal populations. RNA blot analysis revealed low levels of the 2.7 kb transcript of hsp70.2 in several areas of the brain, with highest signal in the hippocampus. Abundant expression of a slightly larger (approximately 2.8 kb) 'antisense' transcript was detected in several brain regions, notably in the brainstem, cerebellum, mesencephalic tectum, thalamus, cortex, and hippocampus. In situ hybridization revealed that the sense and antisense transcripts were both predominantly neuronal and localized to the same cell types in the granular layer of the cerebellum, trapezoid nucleus of the superior olivary complex, locus coeruleus and hippocampus. The hsp70.2 antisense transcripts were particularly abundant in the frontal cortex, dentate gyrus, subthalamic nucleus, zona incerta, superior and inferior colliculi, central gray, brainstem, and cerebellar Purkinje cells. Our findings have revealed a distinct cellular and spatial localization of both sense and antisense transcripts, demonstrating a new level of complexity in the function of the heat shock genes.

  12. Evaluation of brain perfusion in specific Brodmann areas in Frontotemporal dementia and Alzheimer disease using automated 3-D voxel based analysis

    International Nuclear Information System (INIS)

    Valotassiou, V; Tsougos, I; Tzavara, C; Georgoulias, P; Papatriantafyllou, J; Karageorgiou, C; Sifakis, N; Zerva, C

    2009-01-01

    Introduction. Brain perfusion studies with single-photon emission computed tomography (SPECT) have been applied in demented patients to provide better discrimination between frontotemporal dementia (FTD) and Alzheimer's disease (AD). Aim. To assess the perfusion of specific Brodmann (Br) areas of the brain cortex in FTD and AD patients, using NeuroGam processing program to provide 3D voxel-by-voxel cerebral SPECT analysis. Material and methods. We studied 34 consecutive patients. We used the established criteria for the diagnosis of dementia and the specific established criteria for the diagnosis of FTD and AD. All the patients had a neuropsychological evaluation with a battery of tests including the mini-mental state examination (MMSE).Twenty-six patients (16 males, 10 females, mean age 68.76±6.51 years, education 11.81±4.25 years, MMSE 16.69±9.89) received the diagnosis of FTD and 8 patients (all females, mean age 71.25±10.48 years, education 10±4.6 years, MMSE 12.5±3.89) the diagnosis of AD. All the patients underwent a brain SPECT. We applied the NeuroGam Software for the evaluation of brain perfusion in specific Br areas in the left (L) and right (R) hemispheres. Results. Statistically significant hypoperfusion in FTD compared to AD patients, was found in the following Br areas: 11L (p<0.0001), 11R, 20L, 20R, 32L, 38L, 38R, 44L (p<0.001), 32R, 36L, 36R, 45L, 45R, 47R (p<0.01), 9L, 21L, 39R, 44R, 46R, 47L (p<0.05). On the contrary, AD patients presented significant (p<0.05) hypoperfusion in 7R and 39R Br areas. Conclusion. NeuroGam processing program of brain perfusion SPECT could result in enhanced accuracy for the differential diagnosis between AD and FTD patients.

  13. Evaluation of brain perfusion in specific Brodmann areas in Frontotemporal dementia and Alzheimer disease using automated 3-D voxel based analysis

    Science.gov (United States)

    Valotassiou, V.; Papatriantafyllou, J.; Sifakis, N.; Karageorgiou, C.; Tsougos, I.; Tzavara, C.; Zerva, C.; Georgoulias, P.

    2009-05-01

    Introduction. Brain perfusion studies with single-photon emission computed tomography (SPECT) have been applied in demented patients to provide better discrimination between frontotemporal dementia (FTD) and Alzheimer's disease (AD). Aim. To assess the perfusion of specific Brodmann (Br) areas of the brain cortex in FTD and AD patients, using NeuroGam processing program to provide 3D voxel-by-voxel cerebral SPECT analysis. Material and methods. We studied 34 consecutive patients. We used the established criteria for the diagnosis of dementia and the specific established criteria for the diagnosis of FTD and AD. All the patients had a neuropsychological evaluation with a battery of tests including the mini-mental state examination (MMSE).Twenty-six patients (16 males, 10 females, mean age 68.76±6.51 years, education 11.81±4.25 years, MMSE 16.69±9.89) received the diagnosis of FTD and 8 patients (all females, mean age 71.25±10.48 years, education 10±4.6 years, MMSE 12.5±3.89) the diagnosis of AD. All the patients underwent a brain SPECT. We applied the NeuroGam Software for the evaluation of brain perfusion in specific Br areas in the left (L) and right (R) hemispheres. Results. Statistically significant hypoperfusion in FTD compared to AD patients, was found in the following Br areas: 11L (p<0.0001), 11R, 20L, 20R, 32L, 38L, 38R, 44L (p<0.001), 32R, 36L, 36R, 45L, 45R, 47R (p<0.01), 9L, 21L, 39R, 44R, 46R, 47L (p<0.05). On the contrary, AD patients presented significant (p<0.05) hypoperfusion in 7R and 39R Br areas. Conclusion. NeuroGam processing program of brain perfusion SPECT could result in enhanced accuracy for the differential diagnosis between AD and FTD patients.

  14. A pilot study into the effects of music therapy on different areas of the brain of individuals with unresponsive wakefulness syndrome

    Science.gov (United States)

    Steinhoff, Nikolaus; Heine, Astrid M.; Vogl, Julia; Weiss, Konrad; Aschraf, Asita; Hajek, Paul; Schnider, Peter; Tucek, Gerhard

    2015-01-01

    The global cerebral network allows music “ to do to us what it does.” While the same music can cause different emotions, the basic emotion of happy and sad songs can, nevertheless, be understood by most people. Consequently, the individual experience of music and its common effect on the human brain is a challenging subject for research. Various activities such as hearing, processing, and performing music provide us with different pictures of cerebral centers in PET. In comparison to these simple acts of experiencing music, the interaction and the therapeutic relationship between the patient and the therapist in Music Therapy (MT) provide us with an additional element in need of investigation. In the course of a pilot study, these problems were approached and reduced to the simple observation of pattern alteration in the brains of four individuals with Unresponsive Wakefulness Syndrome (UWS) during MT. Each patient had three PET investigations: (i) during a resting state, (ii) during the first exposure to MT, and (iii) during the last exposure to MT. Two patients in the MT group received MT for 5 weeks between the 2nd and the 3rd PET (three times a week), while two other patients in the control group had no MT in between. Tracer uptake was measured in the frontal, hippocampal, and cerebellar region of the brain. With certain differences in these three observed brain areas, the tracer uptake in the MT group was higher (34%) than in the control group after 5 weeks. The preliminary results suggest that MT activates the three brain regions described above. In this article, we present our approach to the neuroscience of MT and discuss the impact of our hypothesis on music therapy practice, neurological rehabilitation of individuals in UWS and additional neuroscientific research. PMID:26347603

  15. Quantitative assessment of the synergistic and independent effects of estradiol and progesterone on ventromedial hypothalamic and preoptic-area proteins in female rat brain

    International Nuclear Information System (INIS)

    Jones, K.J.; McEwen, B.S.; Pfaff, D.W.

    1987-01-01

    In this study, quantitative assessment of the synergistic and independent effects of estradiol and progesterone on protein synthesis in the ventromedial hypothalamus (VMN) and the preoptic area (POA) was accomplished using in vitro 35S-methionine and 35S-cystein labeling, two-dimensional gel electrophoresis, and computerized densitometry. Ovariectomized (OVX) rats were divided into four groups. Group 1 was implanted with estradiol (E) capsules for 6 hr and injected with progesterone (P; 0.1 ml, 5 mg/ml propylene glycol) at 20 hr. Group 3 was sham-implanted for 6 hr and injected with 0.01 ml P at 20 hr. Group 4 was sham-planted for 6 hr and injected with vehicle alone at 20 hr. All animals were sacrificed at 24 hr. A number of proteins in both VMN and POA were found to be increased or decreased in labeling by E plus P, E alone, and P alone. Two important synergistic effects of the hormones were found. First, the effects of E on labeling of several proteins in both brain regions were countered by P, and conversely, the effects of P on labeling of several proteins in both brain regions were countered by E. Second, E priming increased the number of proteins affected in labeling by P in both brain regions. Comparison of the effects of E and P on proteins in the VMN and POA indicated that the populations of proteins affected in labeling were markedly different. These results begin to clarify the mechanism in which E and P affect neuronal functioning in two regions involved in the control of reproduction and lend support to the hypothesis that gonadal steroids accomplished their action on brain tissue via a mechanism that is partly unique to the brain region

  16. Subliminal and Supraliminal Processing of Facial Expression of Emotions: Brain Oscillation in the Left/Right Frontal Area

    OpenAIRE

    Balconi, Michela; Ferrari, Chiara

    2012-01-01

    The unconscious effects of an emotional stimulus have been highlighted by a vast amount of research, whereover it remains questionable whether it is possible to assign a specific function to cortical brain oscillations in the unconscious perception of facial expressions of emotions. Alpha band variation was monitored within the right- and left-cortical side when subjects consciously (supraliminal stimulation) or unconsciously (subliminal stimulation) processed facial patterns. Twenty subjects...

  17. A Free-Choice High-Fat High-Sugar Diet Alters Day-Night Per2 Gene Expression in Reward-Related Brain Areas in Rats.

    Science.gov (United States)

    Blancas-Velazquez, Aurea Susana; Unmehopa, Unga A; Eggels, Leslie; Koekkoek, Laura; Kalsbeek, Andries; Mendoza, Jorge; la Fleur, Susanne E

    2018-01-01

    Under normal light-dark conditions, nocturnal rodents consume most of their food during the dark period. Diets high in fat and sugar, however, may affect the day-night feeding rhythm resulting in a higher light phase intake. In vitro and in vivo studies showed that nutrients affect clock-gene expression. We therefore hypothesized that overconsuming fat and sugar alters clock-gene expression in brain structures important for feeding behavior. We determined the effects of a free-choice high-fat high-sugar (fcHFHS) diet on clock-gene expression in rat brain areas related to feeding and reward and compared them with chow-fed rats. Consuming a fcHFHS diet for 6 weeks disrupted day-night differences in Per2 mRNA expression in the nucleus accumbens (NAc) and lateral hypothalamus but not in the suprachiasmatic nucleus, habenula, and ventral tegmental area. Furthermore, short-term sugar drinking, but not fat feeding, upregulates Per2 mRNA expression in the NAc. The disruptions in day-night differences in NAc Per2 gene expression were not accompanied by altered day-night differences in the mRNA expression of peptides related to food intake. We conclude that the fcHFHS diet and acute sugar drinking affect Per2 gene expression in areas involved in food reward; however, this is not sufficient to alter the day-night pattern of food intake.

  18. Awake craniotomy for brain lesions within and near the primary motor area: A retrospective analysis of factors associated with worsened paresis in 102 consecutive patients

    Science.gov (United States)

    Shinoura, Nobusada; Midorikawa, Akira; Yamada, Ryoji; Hana, Taijun; Saito, Akira; Hiromitsu, Kentaro; Itoi, Chisato; Saito, Syoko; Yagi, Kazuo

    2013-01-01

    Background: We analyzed factors associated with worsened paresis in a large series of patients with brain lesions located within or near the primary motor area (M1) to establish protocols for safe, awake craniotomy of eloquent lesions. Methods: We studied patients with brain lesions involving M1, the premotor area (PMA) and the primary sensory area (S1), who underwent awake craniotomy (n = 102). In addition to evaluating paresis before, during, and one month after surgery, the following parameters were analyzed: Intraoperative complications; success or failure of awake surgery; tumor type (A or B), tumor location, tumor histology, tumor size, and completeness of resection. Results: Worsened paresis at one month of follow-up was significantly associated with failure of awake surgery, intraoperative complications and worsened paresis immediately after surgery, which in turn was significantly associated with intraoperative worsening of paresis. Intraoperative worsening of paresis was significantly related to preoperative paresis, type A tumor (motor tract running in close proximity to and compressed by the tumor), tumor location within or including M1 and partial removal (PR) of the tumor. Conclusions: Successful awake surgery and prevention of deterioration of paresis immediately after surgery without intraoperative complications may help prevent worsening of paresis at one month. Factors associated with intraoperative worsening of paresis were preoperative motor deficit, type A and tumor location in M1, possibly leading to PR of the tumor. PMID:24381792

  19. Characterization of a cerebral palsy-like model in rats: Analysis of gait pattern and of brain and spinal cord motor areas.

    Science.gov (United States)

    Dos Santos, Adriana Souza; de Almeida, Wellington; Popik, Bruno; Sbardelotto, Bruno Marques; Torrejais, Márcia Miranda; de Souza, Marcelo Alves; Centenaro, Lígia Aline

    2017-08-01

    In an attempt to propose an animal model that reproduces in rats the phenotype of cerebral palsy, this study evaluated the effects of maternal exposure to bacterial endotoxin associated with perinatal asphyxia and sensorimotor restriction on gait pattern, brain and spinal cord morphology. Two experimental groups were used: Control Group (CTG) - offspring of rats injected with saline during pregnancy and Cerebral Palsy Group (CPG) - offspring of rats injected with lipopolysaccharide during pregnancy, submitted to perinatal asphyxia and sensorimotor restriction for 30days. At 29days of age, the CPG exhibited coordination between limbs, weight-supported dorsal steps or weight-supported plantar steps with paw rotation. At 45days of age, CPG exhibited plantar stepping with the paw rotated in the balance phase. An increase in the number of glial cells in the primary somatosensory cortex and dorsal striatum were observed in the CPG, but the corpus callosum thickness and cross-sectional area of lateral ventricle were similar between studied groups. No changes were found in the number of motoneurons, glial cells and soma area of the motoneurons in the ventral horn of spinal cord. The combination of insults in the pre, peri and postnatal periods produced changes in hindlimbs gait pattern of animals similar to those observed in diplegic patients, but motor impairments were attenuated over time. Besides, the greater number of glial cells observed seems to be related to the formation of a glial scar in important sensorimotor brain areas. Copyright © 2017 ISDN. Published by Elsevier Ltd. All rights reserved.

  20. Neural reactivity to visual food stimuli is reduced in some areas of the brain during evening hours compared to morning hours: an fMRI study in women.

    Science.gov (United States)

    Masterson, Travis D; Kirwan, C Brock; Davidson, Lance E; LeCheminant, James D

    2016-03-01

    The extent that neural responsiveness to visual food stimuli is influenced by time of day is not well examined. Using a crossover design, 15 healthy women were scanned using fMRI while presented with low- and high-energy pictures of food, once in the morning (6:30-8:30 am) and once in the evening (5:00-7:00 pm). Diets were identical on both days of the fMRI scans and were verified using weighed food records. Visual analog scales were used to record subjective perception of hunger and preoccupation with food prior to each fMRI scan. Six areas of the brain showed lower activation in the evening to both high- and low-energy foods, including structures in reward pathways (P foods compared to low-energy foods (P food stimuli tended to produce greater fMRI responses than low-energy food stimuli in specific areas of the brain, regardless of time of day. However, evening scans showed a lower response to both low- and high-energy food pictures in some areas of the brain. Subjectively, participants reported no difference in hunger by time of day (F = 1.84, P = 0.19), but reported they could eat more (F = 4.83, P = 0.04) and were more preoccupied with thoughts of food (F = 5.51, P = 0.03) in the evening compared to the morning. These data underscore the role that time of day may have on neural responses to food stimuli. These results may also have clinical implications for fMRI measurement in order to prevent a time of day bias.

  1. 28 June 2012 - Members of the European Brain Council led by President Mary Baker visiting the LHC tunnel at Point 5 with Technology Department Group Leader L. Bottura and CMS experimental area with Run Coordinator M. Chamizo-Llatas.

    CERN Multimedia

    Jean-Claude Gadmer

    2012-01-01

    28 June 2012 - Members of the European Brain Council led by President Mary Baker visiting the LHC tunnel at Point 5 with Technology Department Group Leader L. Bottura and CMS experimental area with Run Coordinator M. Chamizo-Llatas.

  2. Physics of the Brain: Interaction of the Optical-Fiber-Guided Multi-Ultraviolet-Photon Beams with the Epilepsy Topion, (the Seizure Onset Area)

    Science.gov (United States)

    Stefan, V. Alexander

    A novel method for the possible prevention of epileptic seizures is proposed, based on the multi-ultraviolet-photon beam interaction with the epilepsy topion, (nonlinear coupling of an ultra high frequency mode to the brain beta phonons). It is hypothesized that epilepsy is a chaotic-dynamics phenomenon: small electrical changes in the epilepsy-topion lead, (within the 10s of milliseconds), to the onset of chaos, (seizure--excessive electrical discharge), and subsequent cascading into adjacent areas. The ultraviolet photons may control the imbalance of sodium and potassium ions and, consequently, may prove to be efficient in the prevention of epileptic seizures. Supported by Nikola Tesla Labs, Stefan University.

  3. Probabilistic fiber tracking of the language and motor white matter pathways of the supplementary motor area (SMA) in patients with brain tumors.

    Science.gov (United States)

    Jenabi, Mehrnaz; Peck, Kyung K; Young, Robert J; Brennan, Nicole; Holodny, Andrei I

    2014-12-01

    Accurate localization of anatomically and functionally separate SMA tracts is important to improve planning prior to neurosurgery. Using fMRI and probabilistic DTI techniques, we assessed the connectivity between the frontal language area (Broca's area) and the rostral pre-SMA (language SMA) and caudal SMA proper (motor SMA). Twenty brain tumor patients completed motor and language fMRI paradigms and DTI. Peaks of functional activity in the language SMA, motor SMA and Broca's area were used to define seed regions for probabilistic tractography. fMRI and probabilistic tractography identified separate and unique pathways connecting the SMA to Broca's area - the language SMA pathway and the motor SMA pathway. For all subjects, the language SMA pathway had a larger number of voxels (PProbabilistic tractography can identify unique white matter tracts that connect language SMA and motor SMA to Broca's area. The language SMA is more significantly connected to Broca's area than is the motor subdivision of the SMA proper. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  4. Categorization for Faces and Tools—Two Classes of Objects Shaped by Different Experience—Differs in Processing Timing, Brain Areas Involved, and Repetition Effects

    Science.gov (United States)

    Kozunov, Vladimir; Nikolaeva, Anastasia; Stroganova, Tatiana A.

    2018-01-01

    The brain mechanisms that integrate the separate features of sensory input into a meaningful percept depend upon the prior experience of interaction with the object and differ between categories of objects. Recent studies using representational similarity analysis (RSA) have characterized either the spatial patterns of brain activity for different categories of objects or described how category structure in neuronal representations emerges in time, but never simultaneously. Here we applied a novel, region-based, multivariate pattern classification approach in combination with RSA to magnetoencephalography data to extract activity associated with qualitatively distinct processing stages of visual perception. We asked participants to name what they see whilst viewing bitonal visual stimuli of two categories predominantly shaped by either value-dependent or sensorimotor experience, namely faces and tools, and meaningless images. We aimed to disambiguate the spatiotemporal patterns of brain activity between the meaningful categories and determine which differences in their processing were attributable to either perceptual categorization per se, or later-stage mentalizing-related processes. We have extracted three stages of cortical activity corresponding to low-level processing, category-specific feature binding, and supra-categorical processing. All face-specific spatiotemporal patterns were associated with bilateral activation of ventral occipito-temporal areas during the feature binding stage at 140–170 ms. The tool-specific activity was found both within the categorization stage and in a later period not thought to be associated with binding processes. The tool-specific binding-related activity was detected within a 210–220 ms window and was located to the intraparietal sulcus of the left hemisphere. Brain activity common for both meaningful categories started at 250 ms and included widely distributed assemblies within parietal, temporal, and prefrontal regions

  5. Categorization for Faces and Tools-Two Classes of Objects Shaped by Different Experience-Differs in Processing Timing, Brain Areas Involved, and Repetition Effects.

    Science.gov (United States)

    Kozunov, Vladimir; Nikolaeva, Anastasia; Stroganova, Tatiana A

    2017-01-01

    The brain mechanisms that integrate the separate features of sensory input into a meaningful percept depend upon the prior experience of interaction with the object and differ between categories of objects. Recent studies using representational similarity analysis (RSA) have characterized either the spatial patterns of brain activity for different categories of objects or described how category structure in neuronal representations emerges in time, but never simultaneously. Here we applied a novel, region-based, multivariate pattern classification approach in combination with RSA to magnetoencephalography data to extract activity associated with qualitatively distinct processing stages of visual perception. We asked participants to name what they see whilst viewing bitonal visual stimuli of two categories predominantly shaped by either value-dependent or sensorimotor experience, namely faces and tools, and meaningless images. We aimed to disambiguate the spatiotemporal patterns of brain activity between the meaningful categories and determine which differences in their processing were attributable to either perceptual categorization per se , or later-stage mentalizing-related processes. We have extracted three stages of cortical activity corresponding to low-level processing, category-specific feature binding, and supra-categorical processing. All face-specific spatiotemporal patterns were associated with bilateral activation of ventral occipito-temporal areas during the feature binding stage at 140-170 ms. The tool-specific activity was found both within the categorization stage and in a later period not thought to be associated with binding processes. The tool-specific binding-related activity was detected within a 210-220 ms window and was located to the intraparietal sulcus of the left hemisphere. Brain activity common for both meaningful categories started at 250 ms and included widely distributed assemblies within parietal, temporal, and prefrontal regions

  6. Subliminal and supraliminal processing of facial expression of emotions: brain oscillation in the left/right frontal area.

    Science.gov (United States)

    Balconi, Michela; Ferrari, Chiara

    2012-03-26

    The unconscious effects of an emotional stimulus have been highlighted by a vast amount of research, whereover it remains questionable whether it is possible to assign a specific function to cortical brain oscillations in the unconscious perception of facial expressions of emotions. Alpha band variation was monitored within the right- and left-cortical side when subjects consciously (supraliminal stimulation) or unconsciously (subliminal stimulation) processed facial patterns. Twenty subjects looked at six facial expressions of emotions (anger, fear, surprise, disgust, happiness, sadness, and neutral) under two different conditions: supraliminal (200 ms) vs. subliminal (30 ms) stimulation (140 target-mask pairs for each condition). The results showed that conscious/unconscious processing and the significance of the stimulus can modulate the alpha power. Moreover, it was found that there was an increased right frontal activity for negative emotions vs. an increased left response for positive emotion. The significance of facial expressions was adduced to elucidate cortical different responses to emotional types.

  7. fMRI activation in the middle frontal gyrus as an indicator of hemispheric dominance for language in brain tumor patients: a comparison with Broca's area.

    Science.gov (United States)

    Dong, Jian W; Brennan, Nicole M Petrovich; Izzo, Giana; Peck, Kyung K; Holodny, Andrei I

    2016-05-01

    Functional MRI (fMRI) can assess language lateralization in brain tumor patients; however, this can be limited if the primary language area-Broca's area (BA)-is affected by the tumor. We hypothesized that the middle frontal gyrus (MFG) can be used as a clinical indicator of hemispheric dominance for language during presurgical workup. Fifty-two right-handed subjects with solitary left-hemispheric primary brain tumors were retrospectively studied. Subjects performed a verbal fluency task during fMRI. The MFG was compared to BA for fMRI voxel activation, language laterality index (LI), and the effect of tumor grade on the LI. Language fMRI (verbal fluency) activated more voxels in MFG than in BA (MFG = 315, BA = 216, p hemispheric MFG and BA were positively correlated (r = 0.69, p hemispheric dominance for language using a measure of verbal fluency and may be an adjunct measure in the clinical determination of language laterality for presurgical planning.

  8. Relationship between extent of brain hypoperfused area and functional outcome in patients with a small subcortical infarction

    International Nuclear Information System (INIS)

    Isaka, Yoshinari; Imaizumi, Masatoshi; Ashida, Keiichi; Nakayama, Hirofumi; Iiji, Osamu; Itoi, Yoshihito; Furukawa, Toshiyuki

    1992-01-01

    We performed 123 I-IMP single photon emission computed tomography (SPECT) in 43 patients who had a small infarction ( 2 =29.3; p 123 I-IMP SPECT in patients with a small infarction may discriminate lacunar infarction from embolic or hemodynamic infarction, which was caused by vascular lesions of major cerebral arteries, in subcortical area. Our study suggests that functional outcome is better in lacunar infarction than embolic or hemodynamic infarction in subcortical area. (author)

  9. Absolute method of measuring magnetic susceptibility

    Science.gov (United States)

    Thorpe, A.; Senftle, F.E.

    1959-01-01

    An absolute method of standardization and measurement of the magnetic susceptibility of small samples is presented which can be applied to most techniques based on the Faraday method. The fact that the susceptibility is a function of the area under the curve of sample displacement versus distance of the magnet from the sample, offers a simple method of measuring the susceptibility without recourse to a standard sample. Typical results on a few substances are compared with reported values, and an error of less than 2% can be achieved. ?? 1959 The American Institute of Physics.

  10. Ghrelin agonists impact on Fos protein expression in brain areas related to food intake regulation in male C57BL/6 mice.

    Science.gov (United States)

    Pirnik, Z; Bundziková, J; Holubová, M; Pýchová, M; Fehrentz, J A; Martinez, J; Zelezná, B; Maletínská, L; Kiss, A

    2011-11-01

    Many peripheral substances, including ghrelin, induce neuronal activation in the brain. In the present study, we compared the effect of subcutaneously administered ghrelin and its three stable agonists: Dpr(3)ghr ([Dpr(N-octanoyl)(3)] ghrelin) (Dpr - diaminopropionic acid), YA GHRP-6 (H-Tyr-Ala-His-DTrp-Ala-Trp-DPhe-Lys-NH(2)), and JMV1843 (H-Aib-DTrp-D-gTrp-CHO) on the Fos expression in food intake-responsive brain areas such as the hypothalamic paraventricular (PVN) and arcuate (ARC) nuclei, the nucleus of the solitary tract (NTS), and area postrema (AP) in male C57BL/6 mice. Immunohistochemical analysis showed that acute subcutaneous dose of each substance (5mg/kg b.w.), which induced a significant food intake increase, elevated Fos protein expression in all brain areas studied. Likewise ghrelin, each agonist tested induced distinct Fos expression overall the PVN. In the ARC, ghrelin and its agonists specifically activated similarly distributed neurons. Fos occurrence extended from the anterior (aARC) to middle (mARC) ARC region. In the latter part of the ARC, the Fos profiles were localized bilaterally, especially in the ventromedial portions of the nucleus. In the NTS, all substances tested also significantly increased the number of Fos profiles in neurons, which also revealed specific location, i.e., in the NTS dorsomedial subnucleus (dmNTS) and the area subpostrema (AsP). In addition, cells located nearby the NTS, in the AP, also revealed a significant increase in number of Fos-activated cells. These results demonstrate for the first time that ghrelin agonists, regardless of their different chemical nature, have a significant and similar activating impact on specific groups of neurons that can be a part of the circuits involved in the food intake regulation. Therefore there is a real potency for ghrelin agonists to treat cachexia and food intake disorders. Thus, likewise JMV1843, the other ghrelin agonists represent substances that might be involved in

  11. Subliminal and Supraliminal Processing of Facial Expression of Emotions: Brain Oscillation in the Left/Right Frontal Area

    Directory of Open Access Journals (Sweden)

    Michela Balconi

    2012-03-01

    Full Text Available The unconscious effects of an emotional stimulus have been highlighted by a vast amount of research, whereover it remains questionable whether it is possible to assign a specific function to cortical brain oscillations in the unconscious perception of facial expressions of emotions. Alpha band variation was monitored within the right- and left-cortical side when subjects consciously (supraliminal stimulation or unconsciously (subliminal stimulation processed facial patterns. Twenty subjects looked at six facial expressions of emotions (anger, fear, surprise, disgust, happiness, sadness, and neutral under two different conditions: supraliminal (200 ms vs. subliminal (30 ms stimulation (140 target-mask pairs for each condition. The results showed that conscious/unconscious processing and the significance of the stimulus can modulate the alpha power. Moreover, it was found that there was an increased right frontal activity for negative emotions vs. an increased left response for positive emotion. The significance of facial expressions was adduced to elucidate cortical different responses to emotional types.

  12. Where one hand meets the other: limb-specific and action-dependent movement plans decoded from preparatory signals in single human frontoparietal brain areas.

    Science.gov (United States)

    Gallivan, Jason P; McLean, D Adam; Flanagan, J Randall; Culham, Jody C

    2013-01-30

    Planning object-directed hand actions requires successful integration of the movement goal with the acting limb. Exactly where and how this sensorimotor integration occurs in the brain has been studied extensively with neurophysiological recordings in nonhuman primates, yet to date, because of limitations of non-invasive methodologies, the ability to examine the same types of planning-related signals in humans has been challenging. Here we show, using a multivoxel pattern analysis of functional MRI (fMRI) data, that the preparatory activity patterns in several frontoparietal brain regions can be used to predict both the limb used and hand action performed in an upcoming movement. Participants performed an event-related delayed movement task whereby they planned and executed grasp or reach actions with either their left or right hand toward a single target object. We found that, although the majority of frontoparietal areas represented hand actions (grasping vs reaching) for the contralateral limb, several areas additionally coded hand actions for the ipsilateral limb. Notable among these were subregions within the posterior parietal cortex (PPC), dorsal premotor cortex (PMd), ventral premotor cortex, dorsolateral prefrontal cortex, presupplementary motor area, and motor cortex, a region more traditionally implicated in contralateral movement generation. Additional analyses suggest that hand actions are represented independently of the intended limb in PPC and PMd. In addition to providing a unique mapping of limb-specific and action-dependent intention-related signals across the human cortical motor system, these findings uncover a much stronger representation of the ipsilateral limb than expected from previous fMRI findings.

  13. Electroencephalographic (eeg coherence between visual and motor areas of the left and the right brain hemisphere while performing visuomotor task with the right and the left hand

    Directory of Open Access Journals (Sweden)

    Simon Brežan

    2007-09-01

    Full Text Available Background: Unilateral limb movements are based on the activation of contralateral primary motor cortex and the bilateral activation of premotor cortices. Performance of a visuomotor task requires a visuomotor integration between motor and visual cortical areas. The functional integration (»binding« of different brain areas, is probably mediated by the synchronous neuronal oscillatory activity, which can be determined by electroencephalographic (EEG coherence analysis. We introduced a new method of coherence analysis and compared coherence and power spectra in the left and right hemisphere for the right vs. left hand visuomotor task, hypothesizing that the increase in coherence and decrease in power spectra while performing the task would be greater in the contralateral hemisphere.Methods: We analyzed 6 healthy subjects and recorded their electroencephalogram during visuomotor task with the right or the left hand. For data analysis, a special Matlab computer programme was designed. The results were statistically analysed by a two-way analysis of variance, one-way analysis of variance and post-hoc t-tests with Bonferroni correction.Results: We demonstrated a significant increase in coherence (p < 0.05 for the visuomotor task compared to control tasks in alpha (8–13 Hz in beta 1 (13–20 Hz frequency bands between visual and motor electrodes. There were no significant differences in coherence nor power spectra depending on the hand used. The changes of coherence and power spectra between both hemispheres were symmetrical.Conclusions: In previous studies, a specific increase of coherence and decrease of power spectra for the visuomotor task was found, but we found no conclusive asymmetries when performing the task with right vs. left hand. This could be explained in a way that increases in coherence and decreases of power spectra reflect symmetrical activation and cooperation between more complex visual and motor brain areas.

  14. Convergence of human brain mapping tools: neuronavigated TMS parameters and fMRI activity in the hand motor area.

    Science.gov (United States)

    Sarfeld, Anna-Sophia; Diekhoff, Svenja; Wang, Ling E; Liuzzi, Gianpiero; Uludağ, Kamil; Eickhoff, Simon B; Fink, Gereon R; Grefkes, Christian

    2012-05-01

    Functional magnetic resonance imaging (fMRI) and transcranial magnetic stimulation (TMS) are well-established tools for investigating the human motor system in-vivo. We here studied the relationship between movement-related fMRI signal changes in the primary motor cortex (M1) and electrophysiological properties of the hand motor area assessed with neuronavigated TMS in 17 healthy subjects. The voxel showing the highest task-related BOLD response in the left hand motor area during right hand movements was identified for each individual subject. This fMRI peak voxel in M1 served as spatial target for coil positioning during neuronavigated TMS. We performed correlation analyses between TMS parameters, BOLD signal estimates and effective connectivity parameters of M1 assessed with dynamic causal modeling (DCM). The results showed a negative correlation between the movement-related BOLD signal in left M1 and resting as well as active motor threshold (MT) obtained for left M1. The DCM analysis revealed that higher excitability of left M1 was associated with a stronger coupling between left supplementary motor area (SMA) and M1. Furthermore, BOLD activity in left M1 correlated with ipsilateral silent period (ISP), i.e. the stronger the task-related BOLD response in left M1, the higher interhemispheric inhibition effects targeting right M1. DCM analyses revealed a positive correlation between the coupling of left SMA with left M1 and the duration of ISP. The data show that TMS parameters assessed for the hand area of M1 do not only reflect the intrinsic properties at the stimulation site but also interactions with remote areas in the human motor system. Copyright © 2011 Wiley-Liss, Inc.

  15. NMDA receptors regulate nicotine-enhanced brain reward function and intravenous nicotine self-administration: role of the ventral tegmental area and central nucleus of the amygdala.

    Science.gov (United States)

    Kenny, Paul J; Chartoff, Elena; Roberto, Marisa; Carlezon, William A; Markou, Athina

    2009-01-01

    Nicotine is considered an important component of tobacco responsible for the smoking habit in humans. Nicotine increases glutamate-mediated transmission throughout brain reward circuitries. This action of nicotine could potentially contribute to its intrinsic rewarding and reward-enhancing properties, which motivate consumption of the drug. Here we show that the competitive N-methyl-D-aspartate (NMDA) receptor antagonist LY235959 (0.5-2.5 mg per kg) abolished nicotine-enhanced brain reward function, reflected in blockade of the lowering of intracranial self-stimulation (ICSS) thresholds usually observed after experimenter-administered (0.25 mg per kg) or intravenously self-administered (0.03 mg per kg per infusion) nicotine injections. The highest LY235959 dose (5 mg per kg) tested reversed the hedonic valence of nicotine from positive to negative, reflected in nicotine-induced elevations of ICSS thresholds. LY235959 doses that reversed nicotine-induced lowering of ICSS thresholds also markedly decreased nicotine self-administration without altering responding for food reinforcement, whereas the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor antagonist NBQX had no effects on nicotine intake. In addition, nicotine self-administration upregulated NMDA receptor subunit expression in the central nucleus of the amygdala (CeA) and ventral tegmental area (VTA), suggesting important interactions between nicotine and the NMDA receptor. Furthermore, nicotine (1 microM) increased NMDA receptor-mediated excitatory postsynaptic currents in rat CeA slices, similar to its previously described effects in the VTA. Finally, infusion of LY235959 (0.1-10 ng per side) into the CeA or VTA decreased nicotine self-administration. Taken together, these data suggest that NMDA receptors, including those in the CeA and VTA, gate the magnitude and valence of the effects of nicotine on brain reward systems, thereby regulating motivation to consume the drug.

  16. Brain aneurysm repair - discharge

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000123.htm Brain aneurysm repair - discharge To use the sharing features ... this page, please enable JavaScript. You had a brain aneurysm . An aneurysm is a weak area in ...

  17. A study on the activation of supplementary motor area in functional magnetic resonance imaging of the brain

    International Nuclear Information System (INIS)

    Jin, Gong Yong; Chung, Gyung Ho; Park, Hark Hoon; Oh, Hee Sul; Kim, Chong Soo; Chung, Jin Young

    1999-01-01

    To evaluate the activated zone of the supplementary motor area through motor and sensory stimulation of both hands by fMRI. Twenty-four healthy volunteers, ranging in age from 20 to 30 years, served as subjects. They were divided into four groups and performed one of the four activation tasks : complex movement, fine movement, touch sensation, heat sensation. Complex movement consisted of a finger task in which subjects flexed and extended all fingers repeatedly in union, without the fingers touching each other(group I). Fine movement involved a thumb task in which subjects flexed and extended the thumb repeatedly without touching the other fingers(group II). Touch sensation consisted of a palm task in which another person repeatedly drew a circle on the subject's palm (group III), and heat sensation involved of a palm task in which subject's palm was touched by another person with a 40 deg C water-bag (group IV). F-MRI was conducted on a commercial 1.5-T scanner equipped with echo-planar imaging. After overlapping images were obtained using a Z-s-core, and the mean/curve in the MR devices was evaluated, the activated zone of the supplementary motor area was also evalvated. Thirty-two of 48 images(20 of the 24 men) revealed activated zones in the supplementary motor area. In group I, activation was observed in five subjects, in three of whom it was bilateral (contralateral activation). In group II, activation was observed in five subjects, in one of whom it was bilateral. In group III, activation occurred in five subjects(bilateral in four, and contralateral in three), and In group IV, activation was also observed in five;in three of these it was bilateral. Using fMRI, and in association with motor and sensory tasks, the supplementary motor area was activated in 66.7% of healthy volunteers (32/48)

  18. Use of near-infrared spectroscopy in the investigation of brain activation during cognitive aging: A systematic review of an emerging area of research.

    Science.gov (United States)

    Agbangla, Nounagnon F; Audiffren, Michel; Albinet, Cédric T

    2017-09-01

    The cognitive neuroscience of aging is a growing and stimulating research area. The development of neuroimaging techniques in the past two decades has considerably increased our understanding of the brain mechanisms that might underlie cognitive performance and resulting changes due to normal aging. Beside traditional metabolic neuroimaging techniques, such as Positron Emission Tomography and functional Magnetic Resonance Imaging, near infrared spectroscopy (NIRS), an optical imaging technique allowing to monitor real-time cerebral blood oxygenation, has gained recent interest in this field. The aim of the present review paper, after briefly presenting the NIRS technique, is to review and to summarize the recent results of neuroimaging studies using this technique in the field of cognitive aging. The reviewed literature shows that, despite low spatial resolution and cerebral depth penetration, this technique provides consistent findings on the reduced hemodynamic activity as a function of chronological age, mainly in the prefrontal cortex. Important moderators of brain hemodynamics, such as cognitive load, subjects' characteristics and experimental conditions, for which the NIRS technique is sensitive, are discussed. Strengths and weaknesses of functional NIRS in the field of cognitive aging are presented and finally, novel perspectives of research are proposed. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Framing susceptibility in a risky choice game is altered by galvanic vestibular stimulation.

    Science.gov (United States)

    Preuss, Nora; Kalla, Roger; Müri, Rene; Mast, Fred W

    2017-06-07

    Recent research provides evidence that galvanic vestibular stimulation (GVS) has a modulating effect on somatosensory perception and spatial cognition. However, other vestibular stimulation techniques have induced changes in affective control and decision making. The aim of this study was to investigate the effect of GVS on framing susceptibility in a risky-choice game. The participants were to decide between a safe and a risky option. The safe option was framed either positively or negatively. During the task, the participants were exposed to either left anodal/right cathodal GVS, right anodal/left cathodal GVS, or sham stimulation (control condition). While left anodal/right cathodal GVS activated more right-hemispheric vestibular brain areas, right anodal/left cathodal GVS resulted in more bilateral activation. We observed increased framing susceptibility during left anodal/right cathodal GVS, but no change in framing susceptibility during right anodal/left cathodal GVS. We propose that GVS results in increased reliance on the affect heuristic by means of activation of cortical and subcortical vestibular-emotional brain structures and that this effect is modulated by the lateralization of the vestibular cortex.

  20. Brain 'talks over' boring quotes: top-down activation of voice-selective areas while listening to monotonous direct speech quotations.

    Science.gov (United States)

    Yao, Bo; Belin, Pascal; Scheepers, Christoph

    2012-04-15

    In human communication, direct speech (e.g., Mary said, "I'm hungry") is perceived as more vivid than indirect speech (e.g., Mary said that she was hungry). This vividness distinction has previously been found to underlie silent reading of quotations: Using functional magnetic resonance imaging (fMRI), we found that direct speech elicited higher brain activity in the temporal voice areas (TVA) of the auditory cortex than indirect speech, consistent with an "inner voice" experience in reading direct speech. Here we show that listening to monotonously spoken direct versus indirect speech quotations also engenders differential TVA activity. This suggests that individuals engage in top-down simulations or imagery of enriched supra-segmental acoustic representations while listening to monotonous direct speech. The findings shed new light on the acoustic nature of the "inner voice" in understanding direct speech. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Brain tumors in eloquent areas: A European multicenter survey of intraoperative mapping techniques, intraoperative seizures occurrence, and antiepileptic drug prophylaxis.

    Science.gov (United States)

    Spena, Giannantonio; Schucht, Philippe; Seidel, Kathleen; Rutten, Geert-Jan; Freyschlag, Christian Franz; D'Agata, Federico; Costi, Emanule; Zappa, Francesca; Fontanella, Marco; Fontaine, Denys; Almairac, Fabien; Cavallo, Michele; De Bonis, Pasquale; Conesa, Gerardo; Foroglou, Nicholas; Gil-Robles, Santiago; Mandonnet, Emanuel; Martino, Juan; Picht, Thomas; Viegas, Catarina; Wager, Michel; Pallud, Johan

    2017-04-01

    Intraoperative mapping and monitoring techniques for eloquent area tumors are routinely used world wide. Very few data are available regarding mapping and monitoring methods and preferences, intraoperative seizures occurrence and perioperative antiepileptic drug management. A questionnaire was sent to 20 European centers with experience in intraoperative mapping or neurophysiological monitoring for the treatment of eloquent area tumors. Fifteen centers returned the completed questionnaires. Data was available on 2098 patients. 863 patients (41.1%) were operated on through awake surgery and intraoperative mapping, while 1235 patients (58.8%) received asleep surgery and intraoperative electrophysiological monitoring or mapping. There was great heterogeneity between centers with some totally AW oriented (up to 100%) and other almost totally ASL oriented (up to 92%) (31% SD). For awake surgery, 79.9% centers preferred an asleep-awake-asleep anesthesia protocol. Only 53.3% of the centers used ECoG or transcutaneous EEG. The incidence of intraoperative seizures varied significantly between centers, ranging from 2.5% to 54% (p mapping technique and the risk of intraoperative seizures. Moreover, history of preoperative seizures can significantly increase the risk of intraoperative seizures (p mapping and monitoring protocols and the management of peri- and intraoperative seizures. This data can help identify specific aspects that need to be investigated in prospective and controlled studies.

  2. Identifying non-toxic doses of manganese for manganese-enhanced magnetic resonance imaging to map brain areas activated by operant behavior in trained rats.

    Science.gov (United States)

    Gálosi, Rita; Szalay, Csaba; Aradi, Mihály; Perlaki, Gábor; Pál, József; Steier, Roy; Lénárd, László; Karádi, Zoltán

    2017-04-01

    Manganese-enhanced magnetic resonance imaging (MEMRI) offers unique advantages such as studying brain activation in freely moving rats, but its usefulness has not been previously evaluated during operant behavior training. Manganese in a form of MnCl 2 , at a dose of 20mg/kg, was intraperitoneally infused. The administration was repeated and separated by 24h to reach the dose of 40mg/kg or 60mg/kg, respectively. Hepatotoxicity of the MnCl 2 was evaluated by determining serum aspartate aminotransferase, alanine aminotransferase, total bilirubin, albumin and protein levels. Neurological examination was also carried out. The animals were tested in visual cue discriminated operant task. Imaging was performed using a 3T clinical MR scanner. T1 values were determined before and after MnCl 2 administrations. Manganese-enhanced images of each animal were subtracted from their baseline images to calculate decrease in the T1 value (ΔT1) voxel by voxel. The subtracted T1 maps of trained animals performing visual cue discriminated operant task, and those of naive rats were compared. The dose of 60mg/kg MnCl 2 showed hepatotoxic effect, but even these animals did not exhibit neurological symptoms. The dose of 20 and 40mg/kg MnCl 2 increased the number of omissions and did not affect the accuracy of performing the visual cue discriminated operant task. Using the accumulated dose of 40mg/kg, voxels with a significant enhanced ΔT1 value were detected in the following brain areas of the visual cue discriminated operant behavior performed animals compared to those in the controls: the visual, somatosensory, motor and premotor cortices, the insula, cingulate, ectorhinal, entorhinal, perirhinal and piriform cortices, hippocampus, amygdala with amygdalohippocampal areas, dorsal striatum, nucleus accumbens core, substantia nigra, and retrorubral field. In conclusion, the MEMRI proved to be a reliable method to accomplish brain activity mapping in correlation with the operant behavior

  3. Polygenic susceptibility to testicular cancer

    DEFF Research Database (Denmark)

    Litchfield, Kevin; Mitchell, Jonathan S; Shipley, Janet

    2015-01-01

    BACKGROUND: The increasing incidence of testicular germ cell tumour (TGCT) combined with its strong heritable basis suggests that stratified screening for the early detection of TGCT may be clinically useful. We modelled the efficiency of such a personalised screening approach, based on genetic...... known TGCT susceptibility variants. The diagnostic performance of testicular biopsy and non-invasive semen analysis was also assessed, within a simulated combined screening programme. RESULTS: The area under the curve for the TGCT PRS model was 0.72 with individuals in the top 1% of the PRS having...

  4. Study of areas susceptible to mass movements in the Highway RS 486, Route of the Sun Estudo de áreas suscetíveis a movimentos de massa na Rodovia RS-486 – Rota do Sol

    Directory of Open Access Journals (Sweden)

    Michele Monguilhott

    2010-06-01

    Full Text Available

    The development of new urban areas and the necessity of disposing of goods production and increased movement of people requires the intervention of man in areas previously not inhabited or preserved of the human interference. Infrastructural work sites have direct effects on ecosystems and RS/486 causes, beyond the visual impact on the landscape, a strong fragmentation in Atlantic forest. The removal of vegetation around the highway can facilitate the occurrence of natural disasters related to changes in geomorphology and weathering processes may result erosion and soil accommodation. To study the vulnerability and susceptibility the mass movements of the sub-watershed Três Forquilhas river along the highway RS 486 were employed techniques of GIS and remote sensing to produce maps of environmental vulnerability from employment of such variables as land use, geomorphology, geology, digital elevation model (DEM, slope and normalized digital vegetation index (NDVI by applying analytic hierarchy process method (AHP to support decision. The resulting maps matchie the purpose of defining priority areas for action of the Rio Grande do Sul State Civil Defense.

    doi: 10.4336/2010.pfb.30.61.61

    O desenvolvimento de novos aglomerados urbanos, bem como a necessidade de escoamento da produção de bens e a maior circulação de pessoas, exige a intervenção do homem em espaços antes não habitados ou preservados da interferência humana. Obras de infraestrutura têm efeito direto sobre os ecossistemas e a RS 486 provoca, além do impacto visual na paisagem, uma forte fragmentação no bioma Mata Atlântica. A retirada da vegetação no entorno da rodovia pode facilitar a ocorrência de desastres naturais relacionados com mudanças na geomorfologia e nos processos intempéricos, resultando em erosão e acomodação do solo. Com o objetivo de mapear áreas vulneráveis e suscetíveis a movimentos de massa na sub-bacia hidrográfica do Rio Tr

  5. Enhanced brain responses to C-fiber input in the area of secondary hyperalgesia induced by high-frequency electrical stimulation of the skin.

    Science.gov (United States)

    van den Broeke, Emanuel N; Mouraux, André

    2014-11-01

    High-frequency electrical stimulation (HFS) of the human skin induces an increase in both mechanical and heat pain sensitivity in the surrounding unconditioned skin. The aim of this study was to investigate the effect of HFS on the intensity of perception and brain responses elicited by the selective activation of C fibers. HFS was applied to the ventral forearm of 15 healthy volunteers. Temperature-controlled CO2 laser stimulation was used to activate selectively low-threshold C-fiber afferents without concomitantly activating Aδ-fiber afferents. These stimuli were detected with reaction times compatible with the conduction velocity of C fibers. The intensity of perception and event-related brain potentials (ERPs) elicited by thermal stimuli delivered to the surrounding unconditioned skin were recorded before (T0) and after HFS (T1: 20 min after HFS; T2: 45 min after HFS). The contralateral forearm served as a control. Mechanical hyperalgesia following HFS was confirmed by measuring the change in the intensity of perception elicited by mechanical punctate stimuli. HFS resulted in increased intensity of perception to mechanical punctate stimulation and selective C-fiber thermal stimulation at both time points. In contrast, the N2 wave of the ERP elicited by C-fiber stimulation (679 ± 88 ms; means ± SD) was enhanced at T1 but not at T2. The P2 wave (808 ± 105 ms) was unaffected by HFS. Our results suggest that HFS enhances the sensitivity to thermal C-fiber input in the area of secondary hyperalgesia. However, there was no significant enhancement of the magnitude of the C-fiber ERPs at T2, suggesting that quickly adapting C fibers do not contribute to this enhancement. Copyright © 2014 the American Physiological Society.

  6. c-Fos immunoreactivity in prefrontal, basal ganglia and limbic areas of the rat brain after central and peripheral administration of ethanol and its metabolite acetaldehyde.

    Directory of Open Access Journals (Sweden)

    Kristen N. Segovia

    2013-05-01

    Full Text Available Considerable evidence indicates that the metabolite of ethanol (EtOH, acetaldehyde, is biologically active. Acetaldehyde can be formed from EtOH peripherally mainly by alcohol dehydrogenase, and also centrally by catalase. EtOH and acetaldehyde show differences in their behavioral effects depending upon the route of administration. In terms of their effects on motor activity and motivated behaviors, when administered peripherally acetaldehyde tends to be more potent than EtOH but shows very similar potency administered centrally. Since dopamine (DA rich areas have an important role in regulating both motor activity and motivation, the present studies were undertaken to compare the effects of central (intraventricular, ICV and peripheral (intraperitoneal, IP administration of EtOH and acetaldehyde on a cellular marker of brain activity, c-Fos immunoreactivity, in DA innervated areas. Male Sprague-Dawley rats received an IP injection of vehicle, EtOH (0.5 or 2.5 g/kg or acetaldehyde (0.1 or 0.5 g/kg or an ICV injection of vehicle, EtOH or acetaldehyde (2.8 or 14.0 µmoles. IP administration of EtOH minimally induced c-Fos in some regions of the prefrontal cortex and basal ganglia, mainly at the low dose (0.5 g/kg, while IP acetaldehyde induced c-Fos in virtually all the structures studied at both doses. Acetaldehyde administered centrally increased c-Fos in all areas studied, a pattern that was very similar to EtOH. Thus, IP administered acetaldehyde was more efficacious than EtOH at inducing c-Fos expression. However, the general pattern of c-Fos induction promoted by ICV EtOH and acetaldehyde was similar. These results are consistent with the pattern observed in behavioral studies in which both substances produced the same magnitude of effect when injected centrally, and produced differences in potency after peripheral administration.

  7. Genetic susceptibility of periodontitis

    NARCIS (Netherlands)

    Laine, M.L.; Crielaard, W.; Loos, B.G.

    2012-01-01

    In this systematic review, we explore and summarize the peer-reviewed literature on putative genetic risk factors for susceptibility to aggressive and chronic periodontitis. A comprehensive literature search on the PubMed database was performed using the keywords ‘periodontitis’ or ‘periodontal

  8. Novel frontiers in ultra-structural and molecular MRI of the brain.

    Science.gov (United States)

    Duyn, Jeff H; Koretsky, Alan P

    2011-08-01

    Recent developments in the MRI of the brain continue to expand its use in basic and clinical neuroscience. This review highlights some areas of recent progress. Higher magnetic field strengths and improved signal detectors have allowed improved visualization of the various properties of the brain, facilitating the anatomical definition of function-specific areas and their connections. For example, by sensitizing the MRI signal to the magnetic susceptibility of tissue, it is starting to become possible to reveal the laminar structure of the cortex and identify millimeter-scale fiber bundles. Using exogenous contrast agents, and innovative ways to manipulate contrast, it is becoming possible to highlight specific fiber tracts and cell populations. These techniques are bringing us closer to understanding the evolutionary blueprint of the brain, improving the detection and characterization of disease, and help to guide treatment. Recent MRI techniques are leading to more detailed and more specific contrast in the study of the brain.

  9. Landslide susceptibility map: from research to application

    Science.gov (United States)

    Fiorucci, Federica; Reichenbach, Paola; Ardizzone, Francesca; Rossi, Mauro; Felicioni, Giulia; Antonini, Guendalina

    2014-05-01

    Susceptibility map is an important and essential tool in environmental planning, to evaluate landslide hazard and risk and for a correct and responsible management of the territory. Landslide susceptibility is the likelihood of a landslide occurring in an area on the basis of local terrain conditions. Can be expressed as the probability that any given region will be affected by landslides, i.e. an estimate of "where" landslides are likely to occur. In this work we present two examples of landslide susceptibility map prepared for the Umbria Region and for the Perugia Municipality. These two maps were realized following official request from the Regional and Municipal government to the Research Institute for the Hydrogeological Protection (CNR-IRPI). The susceptibility map prepared for the Umbria Region represents the development of previous agreements focused to prepare: i) a landslide inventory map that was included in the Urban Territorial Planning (PUT) and ii) a series of maps for the Regional Plan for Multi-risk Prevention. The activities carried out for the Umbria Region were focused to define and apply methods and techniques for landslide susceptibility zonation. Susceptibility maps were prepared exploiting a multivariate statistical model (linear discriminant analysis) for the five Civil Protection Alert Zones defined in the regional territory. The five resulting maps were tested and validated using the spatial distribution of recent landslide events that occurred in the region. The susceptibility map for the Perugia Municipality was prepared to be integrated as one of the cartographic product in the Municipal development plan (PRG - Piano Regolatore Generale) as required by the existing legislation. At strategic level, one of the main objectives of the PRG, is to establish a framework of knowledge and legal aspects for the management of geo-hydrological risk. At national level most of the susceptibility maps prepared for the PRG, were and still are obtained

  10. Brain imaging and schizophrenia

    International Nuclear Information System (INIS)

    Martinot, J.L.; Dao-Castellana, M.H.

    1991-01-01

    Brain structures and brain function have been investigated by the new brain imaging techniques for more than ten years. In Psychiatry, these techniques could afford a new understanding of mental diseases. In schizophrenic patients, CAT scanner and RMI pointed out statistically significant ventricular enlargments which are presently considered as evidence for abnormalities in brain maturation. Functional imaging techniques reported metabolic dysfunctions in the cortical associative areas which are probably linked to the cognitive features of schizophrenics [fr

  11. The magnetic susceptibility of soils in Krakow, southern Poland

    Science.gov (United States)

    Wojas, Anna

    2017-06-01

    Studies into the magnetic susceptibility have been used to assess the soils contamination in the Krakow area. The results of topsoil (over a 2 × 2 km grid), subsoil (37 shallow holes) and soil samples (112) measurements were presented as maps of soil magnetic susceptibility (both volume and mass) illustrating the distribution of parameters in topsoil horizon (0-10 cm) and differential magnetic susceptibility maps between topsoil horizon and subsoil (40-60 cm). All evidence leads to the finding that the highest values of magnetic susceptibility of soil are found exclusively in industrial areas. Taking into consideration the type of land use, the high median value (89.8 × 10-8 m3kg-1) was obtained for samples of cultivated soils and is likely to be connected with occurrence of fertile soil (chernozem). Moreover, enrichment of soils with Pb and Zn accompanies magnetic susceptibility anomalies in the vicinity of the high roads and in the steelworks area, respectively.

  12. A dual-route perspective on brain activation in response to visual words: evidence for a length by lexicality interaction in the visual word form area (VWFA).

    Science.gov (United States)

    Schurz, Matthias; Sturm, Denise; Richlan, Fabio; Kronbichler, Martin; Ladurner, Gunther; Wimmer, Heinz

    2010-02-01

    Based on our previous work, we expected the Visual Word Form Area (VWFA) in the left ventral visual pathway to be engaged by both whole-word recognition and by serial sublexical coding of letter strings. To examine this double function, a phonological lexical decision task (i.e., "Does xxx sound like an existing word?") presented short and long letter strings of words, pseudohomophones, and pseudowords (e.g., Taxi, Taksi and Tazi). Main findings were that the length effect for words was limited to occipital regions and absent in the VWFA. In contrast, a marked length effect for pseudowords was found throughout the ventral visual pathway including the VWFA, as well as in regions presumably engaged by visual attention and silent-articulatory processes. The length by lexicality interaction on brain activation corresponds to well-established behavioral findings of a length by lexicality interaction on naming latencies and speaks for the engagement of the VWFA by both lexical and sublexical processes. Copyright (c) 2009 Elsevier Inc. All rights reserved.

  13. In situ hybridization on the change of m1 receptor mRNA in different brain areas of aged rats and the effect of Yin tonic Zhimu studied

    International Nuclear Information System (INIS)

    Hu Yaer; Xia Zongqin; Yi Ningyu

    1996-01-01

    The change of gene expression of m1 receptors in different brain areas of aged rats and the effects of water extract of the Yin tonic Zhimu and its active principle ZMS was studied. In situ hybridization using 35 S-labelled m1 and m2 probes and analysis of the autoradiographs using a computerized image-analyzer was selected. The grain density of m1 mRNA in striatum was significantly lowered in old rats as compared with young rats (decreased by 12.26 +- 3.60, P<0.01). Long-term oral administration of ZMS, the active principle of Yin tonic Zhimu but not the water extraction of Zhimu, elevated the m1 mRNA in striatum of aged rats (increased by 15.71 +- 3.27, P<0.01). Neither significant change of the grain density of m1 mRNA in old rats nor significant effect of Zhimu or ZMS was observed in cerebral cortex and hippocampus. The m1 mRNA level in striatum is decreased in aged rats and ZMS is able to elevate it

  14. Differentiation of grade II/III and grade IV glioma by combining ''T1 contrast-enhanced brain perfusion imaging'' and susceptibility-weighted quantitative imaging

    International Nuclear Information System (INIS)

    Saini, Jitender; Gupta, Pradeep Kumar; Gupta, Rakesh Kumar; Sahoo, Prativa; Singh, Anup; Patir, Rana; Ahlawat, Suneeta; Beniwal, Manish; Thennarasu, K.; Santosh, Vani

    2018-01-01

    MRI is a useful method for discriminating low- and high-grade glioma using perfusion MRI and susceptibility-weighted imaging (SWI). The purpose of this study is to evaluate the usefulness of T1-perfusion MRI and SWI in discriminating among grade II, III, and IV gliomas. T1-perfusion MRI was used to measure relative cerebral blood volume (rCBV) in 129 patients with glioma (70 grade IV, 33 grade III, and 26 grade II tumors). SWI was also used to measure the intratumoral susceptibility signal intensity (ITSS) scores for each tumor in these patients. rCBV and ITSS values were compared to seek differences between grade II vs. grade III, grade III vs. grade IV, and grade III+II vs. grade IV tumors. Significant differences in rCBV values of the three grades of the tumors were noted and pairwise comparisons showed significantly higher rCBV values in grade IV tumors as compared to grade III tumors, and similarly increased rCBV was seen in the grade III tumors as compared to grade II tumors (p < 0.001). Grade IV gliomas showed significantly higher ITSS scores on SWI as compared to grade III tumors (p < 0.001) whereas insignificant difference was seen on comparing ITSS scores of grade III with grade II tumors. Combining the rCBV and ITSS resulted in significant improvement in the discrimination of grade III from grade IV tumors. The combination of rCBV values derived from T1-perfusion MRI and SWI derived ITSS scores improves the diagnostic accuracy for discrimination of grade III from grade IV gliomas. (orig.)

  15. Differentiation of grade II/III and grade IV glioma by combining ''T1 contrast-enhanced brain perfusion imaging'' and susceptibility-weighted quantitative imaging

    Energy Technology Data Exchange (ETDEWEB)

    Saini, Jitender [National Institute of Mental Health and Neurosciences, Neuroimaging and Interventional Radiology, Bangalore (India); Gupta, Pradeep Kumar; Gupta, Rakesh Kumar [Fortis Memorial Research Institute, Department of Radiology and Imaging, Gurugram (India); Sahoo, Prativa [Philips Health System, Philips India Limited, Bangalore (India); Beckman Research Institute, Mathematical Oncology, Duarte, CA (United States); Singh, Anup [Indian Institute of Technology Delhi, Center for Biomedical Engineering, Delhi (India); Patir, Rana [Fortis Memorial Research Institute, Department of Neurosurgery, Gurugram (India); Ahlawat, Suneeta [Fortis Memorial Research Institute, SRL Diagnostics, Gurugram (India); Beniwal, Manish [National Institute of Mental Health and Neurosciences, Department of Neurosurgery, Bangalore (India); Thennarasu, K. [National Institute of Mental Health and Neurosciences, Department of Biostatistics, Bangalore (India); Santosh, Vani [National Institute of Mental Health and Neurosciences, Department of Neuropathology, Bangalore (India)

    2018-01-15

    MRI is a useful method for discriminating low- and high-grade glioma using perfusion MRI and susceptibility-weighted imaging (SWI). The purpose of this study is to evaluate the usefulness of T1-perfusion MRI and SWI in discriminating among grade II, III, and IV gliomas. T1-perfusion MRI was used to measure relative cerebral blood volume (rCBV) in 129 patients with glioma (70 grade IV, 33 grade III, and 26 grade II tumors). SWI was also used to measure the intratumoral susceptibility signal intensity (ITSS) scores for each tumor in these patients. rCBV and ITSS values were compared to seek differences between grade II vs. grade III, grade III vs. grade IV, and grade III+II vs. grade IV tumors. Significant differences in rCBV values of the three grades of the tumors were noted and pairwise comparisons showed significantly higher rCBV values in grade IV tumors as compared to grade III tumors, and similarly increased rCBV was seen in the grade III tumors as compared to grade II tumors (p < 0.001). Grade IV gliomas showed significantly higher ITSS scores on SWI as compared to grade III tumors (p < 0.001) whereas insignificant difference was seen on comparing ITSS scores of grade III with grade II tumors. Combining the rCBV and ITSS resulted in significant improvement in the discrimination of grade III from grade IV tumors. The combination of rCBV values derived from T1-perfusion MRI and SWI derived ITSS scores improves the diagnostic accuracy for discrimination of grade III from grade IV gliomas. (orig.)

  16. Landslides susceptibility mapping at Gunung Ciremai National Park

    Science.gov (United States)

    Faizin; Nur, Bambang Azis

    2018-02-01

    In addition to agriculture, tourism became one of primary economic income for communities around Mount Ciremai, West, Java. Unfortunately, the landscape of West Java has many potential causes to disasters, mainly landslides. Mapping of disaster susceptibility area is needed as a consideration of tourism planning. The study was conducted in Gunung Ciremai National Park, West Java. This paper propose a methodology to map landslides susceptibilities based on spatial data. Using Geographic Information System tools, several environmental parameters such as slope, land use, elevation, and lithology are scored to build a landslide susceptibility map. Then, susceptibility map is overlaid with Utilization Zone.

  17. Whole brain and brain regional coexpression network interactions associated with predisposition to alcohol consumption.

    Directory of Open Access Journals (Sweden)

    Lauren A Vanderlinden

    Full Text Available To identify brain transcriptional networks that may predispose an animal to consume alcohol, we used weighted gene coexpression network analysis (WGCNA. Candidate coexpression modules are those with an eigengene expression level that correlates significantly with the level of alcohol consumption across a panel of BXD recombinant inbred mouse strains, and that share a genomic region that regulates the module transcript expression levels (mQTL with a genomic region that regulates alcohol consumption (bQTL. To address a controversy regarding utility of gene expression profiles from whole brain, vs specific brain regions, as indicators of the relationship of gene expression to phenotype, we compared candidate coexpression modules from whole brain gene expression data (gathered with Affymetrix 430 v2 arrays in the Colorado laboratories and from gene expression data from 6 brain regions (nucleus accumbens (NA; prefrontal cortex (PFC; ventral tegmental area (VTA; striatum (ST; hippocampus (HP; cerebellum (CB available from GeneNetwork. The candidate modules were used to construct candidate eigengene networks across brain regions, resulting in three "meta-modules", composed of candidate modules from two or more brain regions (NA, PFC, ST, VTA and whole brain. To mitigate the potential influence of chromosomal location of transcripts and cis-eQTLs in linkage disequilibrium, we calculated a semi-partial correlation of the transcripts in the meta-modules with alcohol consumption conditional on the transcripts' cis-eQTLs. The function of transcripts that retained the correlation with the phenotype after correction for the strong genetic influence, implicates processes of protein metabolism in the ER and Golgi as influencing susceptibility to variation in alcohol consumption. Integration of these data with human GWAS provides further information on the function of polymorphisms associated with alcohol-related traits.

  18. SCC susceptibility evaluation of plastic deformed austenitic stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Kaneshima, Yoshiari; Totsuka, Nobuo; Arioka, Koji [Inst. of Nuclear Safety System Inc., Mihama, Fukui (Japan)

    2002-09-01

    Slow strain rate temperature (SSRT) tests were carried out to evaluate the SCC susceptibility of deformed SUS316 stainless steel in simulated primary water of pressurized water reactor (PWR). The influence of material hardness and temperature on SCC susceptibility was studied. From these tests following results were obtained. (1) Both of the total SCC and IGSCC susceptibilities increased as the hardness of deformed specimens increased. Especially over 250{approx}300HV area, this tendency remarkably increased. (2) The reduction ratio showed a plateau under 300HV area. However, over 300HV area, it decreased remarkably as the hardness increased, that is, the SCC susceptibility remarkably increased. (3) Based on the SSRT test results conducted at 320, 340 and 360degC, the total SCC susceptibility dependence on temperature was small and the IGSCC susceptibility was dependent on the temperature. From these results, the TGSCC susceptibility dependence on temperature was also small. The activation energy of total SCC and IGSCC susceptibility were calculated. (author)

  19. A clearer view of the insect brain – combining bleaching with standard whole-mount immunocytochemistry allows confocal imaging of pigment-covered brain areas for 3D reconstruction.

    Directory of Open Access Journals (Sweden)

    Anna Lisa Stöckl

    2015-09-01

    Full Text Available In the study of insect neuroanatomy, three-dimensional reconstructions of neurons and neuropils have become a standard technique. As images have to be obtained from whole-mount brain preparations, pigmentation on the brain surface poses a serious challenge to imaging. In insects, this is a major problematic in the first visual neuropil of the optic lobe, the lamina, which is obstructed by the pigment of the retina as well as by the pigmented fenestration layer. This has prevented inclusion of this major processing center of the insect visual system into most neuroanatomical brain atlases and hinders imaging of neurons within the lamina by confocal microscopy. It has recently been shown that hydrogen peroxide bleaching is compatible with immunohistochemical labeling in insect brains, and we therefore developed a simple technique for removal of pigments on the surface of insect brains by chemical bleaching. We show that our technique enables imaging of the pigment-obstructed regions of insect brains when combined with standard protocols for both anti-synapsin-labeled as well as neurobiotin-injected samples. This method can be combined with different fixation procedures, as well as different fluorophore excitation wavelengths without negative effects on staining quality. It can therefore serve as an effective addition to most standard histology protocols used in insect neuroanatomy.

  20. 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 ...

  1. The Identification of Fatigue Resistant and Fatigue Susceptible Individuals

    National Research Council Canada - National Science Library

    Harrison, Richard; Chaiken, Scott; Harville, Donald; Fischer, Joseph; Fisher, Dion; Whitmore, Jeff

    2008-01-01

    The present study was designed to target two specific areas regarding fatigue. The primary purpose was to begin investigations into possible genetic markers linked to fatigue resistance and fatigue susceptibility...

  2. Landslide susceptibility zonation in part of Tehri reservoir region ...

    Indian Academy of Sciences (India)

    Validation of the model was performed by using cumulative ..... thrusts, folds and joints of varying shape and size ...... Lee S, Choi J and Min K 2002 Landslide susceptibility analy- ... cross-validation in three test areas using a frequency.

  3. FROM BRAIN DRAIN TO BRAIN NETWORKING

    Directory of Open Access Journals (Sweden)

    Irina BONCEA

    2015-06-01

    Full Text Available Scientific networking is the most accessible way a country can turn the brain drain into brain gain. Diaspora’s members offer valuable information, advice or financial support from the destination country, without being necessary to return. This article aims to investigate Romania’s potential of turning brain drain into brain networking, using evidence from the medical sector. The main factors influencing the collaboration with the country of origin are investigated. The conclusions suggest that Romania could benefit from the diaspora option, through an active implication at institutional level and the implementation of a strategy in this area.

  4. Probing white-matter microstructure with higher-order diffusion tensors and susceptibility tensor MRI

    Science.gov (United States)

    Liu, Chunlei; Murphy, Nicole E.; Li, Wei

    2012-01-01

    Diffusion MRI has become an invaluable tool for studying white matter microstructure and brain connectivity. The emergence of quantitative susceptibility mapping and susceptibility tensor imaging (STI) has provided another unique tool for assessing the structure of white matter. In the highly ordered white matter structure, diffusion MRI measures hindered water mobility induced by various tissue and cell membranes, while susceptibility sensitizes to the molecular composition and axonal arrangement. Integrating these two methods may produce new insights into the complex physiology of white matter. In this study, we investigated the relationship between diffusion and magnetic susceptibility in the white matter. Experiments were conducted on phantoms and human brains in vivo. Diffusion properties were quantified with the diffusion tensor model and also with the higher order tensor model based on the cumulant expansion. Frequency shift and susceptibility tensor were measured with quantitative susceptibility mapping and susceptibility tensor imaging. These diffusion and susceptibility quantities were compared and correlated in regions of single fiber bundles and regions of multiple fiber orientations. Relationships were established with similarities and differences identified. It is believed that diffusion MRI and susceptibility MRI provide complementary information of the microstructure of white matter. Together, they allow a more complete assessment of healthy and diseased brains. PMID:23507987

  5. Stress-induced activation of the immediate early gene Arc (activity-regulated cytoskeleton-associated protein) is restricted to telencephalic areas in the rat brain: relationship to c-fos mRNA.

    Science.gov (United States)

    Ons, Sheila; Martí, Octavi; Armario, Antonio

    2004-06-01

    Arc is an effector immediate early gene whose expression is induced in situations of increased neuronal activity. However, there is no report on the influence of stress on Arc expression. Here, we compared the induction of both c-fos and Arc mRNAs in the brain of rats exposed to one of three different stressful situations: novel environment, forced swimming and immobilization. An absent or weak c-fos mRNA signal was observed in control rats, whereas those exposed to one of three stressors showed enhanced c-fos expression in a wide range of brain areas. Constitutive Arc expression was observed in some areas such as cortex, striatum, hippocampus, reticular thalamic nucleus and cerebellar cortex. In response to stressors, a strong induction of Arc was observed, but the pattern was different from that of c-fos. For instance, activation of Arc but not c-fos was observed in the nucleus accumbens after immobilization and in the hippocampus after novel environment. No Arc induction was observed in diencephalic and brainstem areas. The present data show that Arc has a neuroanatomically restricted pattern of induction in the brain after emotional stress. Telencephalic activation suggests that a more intense induction of synaptic plasticity is occurring in this area after exposure to emotional stressors.

  6. Effects of white matter microstructure on phase and susceptibility maps.

    Science.gov (United States)

    Wharton, Samuel; Bowtell, Richard

    2015-03-01

    To investigate the effects on quantitative susceptibility mapping (QSM) and susceptibility tensor imaging (STI) of the frequency variation produced by the microstructure of white matter (WM). The frequency offsets in a WM tissue sample that are not explained by the effect of bulk isotropic or anisotropic magnetic susceptibility, but rather result from the local microstructure, were characterized for the first time. QSM and STI were then applied to simulated frequency maps that were calculated using a digitized whole-brain, WM model formed from anatomical and diffusion tensor imaging data acquired from a volunteer. In this model, the magnitudes of the frequency contributions due to anisotropy and microstructure were derived from the results of the tissue experiments. The simulations suggest that the frequency contribution of microstructure is much larger than that due to bulk effects of anisotropic magnetic susceptibility. In QSM, the microstructure contribution introduced artificial WM heterogeneity. For the STI processing, the microstructure contribution caused the susceptibility anisotropy to be significantly overestimated. Microstructure-related phase offsets in WM yield artifacts in the calculated susceptibility maps. If susceptibility mapping is to become a robust MRI technique, further research should be carried out to reduce the confounding effects of microstructure-related frequency contributions. © 2014 Wiley Periodicals, Inc.

  7. Diagnostic examination performance by using microvascular leakage, cerebral blood volume, and blood flow derived from 3-T dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging in the differentiation of glioblastoma multiforme and brain metastasis

    International Nuclear Information System (INIS)

    Server, Andres; Nakstad, Per H.; Orheim, Tone E.D.; Graff, Bjoern A.; Josefsen, Roger; Kumar, Theresa

    2011-01-01

    Conventional magnetic resonance (MR) imaging has limited capacity to differentiate between glioblastoma multiforme (GBM) and metastasis. The purposes of this study were: (1) to compare microvascular leakage (MVL), cerebral blood volume (CBV), and blood flow (CBF) in the distinction of metastasis from GBM using dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging (DSC-MRI), and (2) to estimate the diagnostic accuracy of perfusion and permeability MR imaging. A prospective study of 61 patients (40 GBMs and 21 metastases) was performed at 3 T using DSC-MRI. Normalized rCBV and rCBF from tumoral (rCBVt, rCBFt), peri-enhancing region (rCBVe, rCBFe), and by dividing the value in the tumor by the value in the peri-enhancing region (rCBVt/e, rCBFt/e), as well as MVL were calculated. Hemodynamic and histopathologic variables were analyzed statistically and Spearman/Pearson correlations. Receiver operating characteristic curve analysis was performed for each of the variables. The rCBVe, rCBFe, and MVL were significantly greater in GBMs compared with those of metastases. The optimal cutoff value for differentiating GBM from metastasis was 0.80 which implies a sensitivity of 95%, a specificity of 92%, a positive predictive value of 86%, and a negative predictive value of 97% for rCBVe ratio. We found a modest correlation between rCBVt and rCBFt ratios. MVL measurements in GBMs are significantly higher than those in metastases. Statistically, both rCBVe, rCBVt/e and rCBFe, rCBFt/e were useful in differentiating between GBMs and metastases, supporting the hypothesis that perfusion MR imaging can detect infiltration of tumor cells in the peri-enhancing region. (orig.)

  8. Diagnostic examination performance by using microvascular leakage, cerebral blood volume, and blood flow derived from 3-T dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging in the differentiation of glioblastoma multiforme and brain metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Server, Andres; Nakstad, Per H. [Oslo University Hospital-Ullevaal, Section of Neuroradiology, Department of Radiology and Nuclear Medicine, Oslo (Norway); University of Oslo, Oslo (Norway); Orheim, Tone E.D. [Oslo University Hospital, Interventional Centre, Oslo (Norway); Graff, Bjoern A. [Oslo University Hospital-Ullevaal, Department of Radiology and Nuclear Medicine, Oslo (Norway); Josefsen, Roger [Oslo University Hospital-Ullevaal, Department of Neurosurgery, Oslo (Norway); Kumar, Theresa [Oslo University Hospital-Ullevaal, Department of Pathology, Oslo (Norway)

    2011-05-15

    Conventional magnetic resonance (MR) imaging has limited capacity to differentiate between glioblastoma multiforme (GBM) and metastasis. The purposes of this study were: (1) to compare microvascular leakage (MVL), cerebral blood volume (CBV), and blood flow (CBF) in the distinction of metastasis from GBM using dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging (DSC-MRI), and (2) to estimate the diagnostic accuracy of perfusion and permeability MR imaging. A prospective study of 61 patients (40 GBMs and 21 metastases) was performed at 3 T using DSC-MRI. Normalized rCBV and rCBF from tumoral (rCBVt, rCBFt), peri-enhancing region (rCBVe, rCBFe), and by dividing the value in the tumor by the value in the peri-enhancing region (rCBVt/e, rCBFt/e), as well as MVL were calculated. Hemodynamic and histopathologic variables were analyzed statistically and Spearman/Pearson correlations. Receiver operating characteristic curve analysis was performed for each of the variables. The rCBVe, rCBFe, and MVL were significantly greater in GBMs compared with those of metastases. The optimal cutoff value for differentiating GBM from metastasis was 0.80 which implies a sensitivity of 95%, a specificity of 92%, a positive predictive value of 86%, and a negative predictive value of 97% for rCBVe ratio. We found a modest correlation between rCBVt and rCBFt ratios. MVL measurements in GBMs are significantly higher than those in metastases. Statistically, both rCBVe, rCBVt/e and rCBFe, rCBFt/e were useful in differentiating between GBMs and metastases, supporting the hypothesis that perfusion MR imaging can detect infiltration of tumor cells in the peri-enhancing region. (orig.)

  9. Effects of special brain area regional cerebral blood flow abnormal perfusion on learning and memory function and its molecular mechanism in rats

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    s To study the effect of special brain area regional cerebral blood flow (rCBF) abnormal perfusion on learning and memory function and its molecular mechanism,64 adult male healthy Spragne-Dawley (SD) rats were randomly divided into two groups,the false operation group (control group) and the operation group (model group).After surgical operation,the operation group undertook bilateral common carotid artery permanent ligation,while the other group did not.Learning and memory function were measured by Y-maze at 4 h,8 h,24 h and 3 d after surgical operation,respectively.The rCBF of the right frontal lobe and hippocampus was also detected by the PerifluxPF model laser Doppler flowmetry,and the expressions of c-fos or c-jun or Bcl-2 and Bax were also measured by immune histochemistry S-P method accordingly.Results showed that the rCBF of the right frontal lobe and hippocampus in the operation group was significantly lower than that in the false operation group (P < 0.05).The learning indexes,error number (EN),day of reach standard and total reaction time (TRT) in the operation group,were significantly higher than that in the false operation group (P< 0.05).However,the initiative evasion rate in the operation group was significantly lower than that in the false operation group.The study also found that the rCBF was relatively more,the indexes (EN,the day of reach standard and TRT) relatively fewer,but the initiative evasion rate and the memory keeping rate were relatively more.The positive expression and the average absorbency of Fos and Jun in the operation group were significantly higher than that in the false operation group (P< 0.05).Furthermore,Bax and Bcl-2 positive cells were all increased over time in the operation group,and the expression ratio of Bax/Bcl-2 in the operation group was significantly higher than that in the false operation group (P<0.01).In conclusion,rCBF decrease can impair the learning and memory function in rats,which may be related to

  10. Afasias e áreas cerebrais: argumentos prós e contras à perspectiva localizacionista Aphasias and brain areas: positive and negative aspects of the localization argument

    Directory of Open Access Journals (Sweden)

    Ana Cláudia C. Vieira

    2011-01-01

    investigate how cortex areas compromised by Cerebral Vascular Accident (CVA are related to the classification of aphasia, since there are controversies about the location of the lesion in the brain and the characteristics related to variations in speech patterns. Through the Montreal-Toulose protocol, 26 right-handed persons who were affected by left cerebral-vascular lesion and have been showing aphasic symptoms have been evaluated. The Montreal-Toulose protocol, initial standard module - version alpha, includes nomination, repetition, oral comprehension, reading and writing comprehension tests as well as an interview, which allows an evaluation of the discourse fluency. The subjects were allocated into four sub-groups, according to the lesion sites: frontal, temporal, temporo-parietal and parieto-occipital. For the analysis of the data, a Multidimensional Similarity Structure Analysis (SSA was carried out along with an external variable method. The results show a high positive correlation between the lesion in the brain's frontal lobe and difficulties in the discourse fluency as well as a high positive correlation between the lesion in the brain's temporal lobe and hindrances in all abilities tested: nomination, repetition, oral comprehension, reading and writing comprehension. It is in accordance with localizational studies, since it highlights the fundamental role of the temporal lobe for the language and the importance of the frontal lobe for the speech praxis. However, in the remaining sub-groups (temporo-parietal and parieto-occipital there have been positive correlations only between oral comprehension and repetition, with the latter showing correlation only with the second group and presenting a low score. High negative correlations with the discourse fluency were observed. It suggests that this ability has remained preserved in those groups, which in turns weakens the localization argument.

  11. Comparison of susceptibility to antibiotics of Staphylococcus aureus isolated from fresh cheeses and clinical samples from the Area Metropolitana and evaluation of the presence of Listeria monocytogenes in the same foodstuff

    International Nuclear Information System (INIS)

    Piedra Ramirez, Hiryna

    2014-01-01

    60 samples of fresh cheeses were analyzed from the central markets of Alajuela, Heredia, Cartago and San Jose. Staphylococcus aureus, total coliform and thermotolerant counts were performed, as well as Escherichia coli by the NMP technique. The presence of Listeria monocytogenes was evaluated in 25 g of cheese. The confirmatory identification and sensitivity profile of S. aureus strains were obtained using the Vitek system. L. monocytogenes were identified by means of biochemical tests. The statistical package Statistical Package for the Social Sciences (SPSS) and Excell were used to analyze the data. The presence of fecal contamination was identified as well as S. aureus in fresh cheeses from the four provinces studied. The comparative analysis of S. aureus antibiotic susceptibility profiles from clinical specimens and cheeses, for the majority of antibiotics under study was able to determine that the sensitivity patterns shown have been different. The clinical strains of origin could be observed with a pattern of multiresistance more marked than the strains of alimentary origin. The presence of L. monocytogenes was identified in an important percentage of cheese samples. (author) [es

  12. Local quantum thermal susceptibility

    Science.gov (United States)

    de Pasquale, Antonella; Rossini, Davide; Fazio, Rosario; Giovannetti, Vittorio

    2016-09-01

    Thermodynamics relies on the possibility to describe systems composed of a large number of constituents in terms of few macroscopic variables. Its foundations are rooted into the paradigm of statistical mechanics, where thermal properties originate from averaging procedures which smoothen out local details. While undoubtedly successful, elegant and formally correct, this approach carries over an operational problem, namely determining the precision at which such variables are inferred, when technical/practical limitations restrict our capabilities to local probing. Here we introduce the local quantum thermal susceptibility, a quantifier for the best achievable accuracy for temperature estimation via local measurements. Our method relies on basic concepts of quantum estimation theory, providing an operative strategy to address the local thermal response of arbitrary quantum systems at equilibrium. At low temperatures, it highlights the local distinguishability of the ground state from the excited sub-manifolds, thus providing a method to locate quantum phase transitions.

  13. Topological Susceptibility from Slabs

    CERN Document Server

    Bietenholz, Wolfgang; Gerber, Urs

    2015-01-01

    In quantum field theories with topological sectors, a non-perturbative quantity of interest is the topological susceptibility chi_t. In principle it seems straightforward to measure chi_t by means of Monte Carlo simulations. However, for local update algorithms and fine lattice spacings, this tends to be difficult, since the Monte Carlo history rarely changes the topological sector. Here we test a method to measure chi_t even if data from only one sector are available. It is based on the topological charges in sub-volumes, which we denote as slabs. Assuming a Gaussian distribution of these charges, this method enables the evaluation of chi_t, as we demonstrate with numerical results for non-linear sigma-models.

  14. Topological susceptibility from slabs

    Energy Technology Data Exchange (ETDEWEB)

    Bietenholz, Wolfgang [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, A.P. 70-543, Distrito Federal, C.P. 04510 (Mexico); Forcrand, Philippe de [Institute for Theoretical Physics, ETH Zürich,CH-8093 Zürich (Switzerland); CERN, Physics Department, TH Unit, CH-1211 Geneva 23 (Switzerland); Gerber, Urs [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, A.P. 70-543, Distrito Federal, C.P. 04510 (Mexico); Instituto de Física y Matemáticas, Universidad Michoacana de San Nicolás de Hidalgo,Edificio C-3, Apdo. Postal 2-82, Morelia, Michoacán, C.P. 58040 (Mexico)

    2015-12-14

    In quantum field theories with topological sectors, a non-perturbative quantity of interest is the topological susceptibility χ{sub t}. In principle it seems straightforward to measure χ{sub t} by means of Monte Carlo simulations. However, for local update algorithms and fine lattice spacings, this tends to be difficult, since the Monte Carlo history rarely changes the topological sector. Here we test a method to measure χ{sub t} even if data from only one sector are available. It is based on the topological charges in sub-volumes, which we denote as slabs. Assuming a Gaussian distribution of these charges, this method enables the evaluation of χ{sub t}, as we demonstrate with numerical results for non-linear σ-models.

  15. Local quantum thermal susceptibility

    Science.gov (United States)

    De Pasquale, Antonella; Rossini, Davide; Fazio, Rosario; Giovannetti, Vittorio

    2016-01-01

    Thermodynamics relies on the possibility to describe systems composed of a large number of constituents in terms of few macroscopic variables. Its foundations are rooted into the paradigm of statistical mechanics, where thermal properties originate from averaging procedures which smoothen out local details. While undoubtedly successful, elegant and formally correct, this approach carries over an operational problem, namely determining the precision at which such variables are inferred, when technical/practical limitations restrict our capabilities to local probing. Here we introduce the local quantum thermal susceptibility, a quantifier for the best achievable accuracy for temperature estimation via local measurements. Our method relies on basic concepts of quantum estimation theory, providing an operative strategy to address the local thermal response of arbitrary quantum systems at equilibrium. At low temperatures, it highlights the local distinguishability of the ground state from the excited sub-manifolds, thus providing a method to locate quantum phase transitions. PMID:27681458

  16. Susceptibility to anchoring effects

    Directory of Open Access Journals (Sweden)

    Todd McElroy

    2007-02-01

    Full Text Available Previous research on anchoring has shown this heuristic to be a very robust psychological phenomenon ubiquitous across many domains of human judgment and decision-making. Despite the prevalence of anchoring effects, researchers have only recently begun to investigate the underlying factors responsible for how and in what ways a person is susceptible to them. This paper examines how one such factor, the Big-Five personality trait of openness-to-experience, influences the effect of previously presented anchors on participants' judgments. Our findings indicate that participants high in openness-to-experience were significantly more influenced by anchoring cues relative to participants low in this trait. These findings were consistent across two different types of anchoring tasks providing convergent evidence for our hypothesis.

  17. Functional MR imaging of the primary motor area in patients with brain tumors of the motor cortex. Evaluation with echo-planer imaging on a clinical 1.0 T MR imager

    International Nuclear Information System (INIS)

    Hara, Yoshie; Nakamura, Mitsugu; Tamaki, Norihiko; Ehara, Kazumasa; Kitamura, Junji

    1998-01-01

    The study included 3 healthy volunteers and 8 patients with a brain tumor of the motor cortex. The fMRI study was based on the spin echo (SE) type single shot echo-planer technique. Ten contiguous axial slices consisted of 40-60 echo-planer images acquired during 80-120 seconds of repeated task performances and resting periods. Activation maps were calculated by a Z-score method with thresholding, and interpolated on T1 images and surface anatomy scans. In all cases, areas of a significant signal increase were detected as clusters of several pixels on the precentral gyrus contralateral to the motor task performance. The mean signal change was 3.6±0.9% in normal subjects, and 7.2±4.1% in brain tumor patients. There was no significant difference between the two groups. In 5 brain tumor patients significant displacement of the precentral gyrus was observed on T1- or T2-weighted SE images. Of these, 2 also had marked peritumoral edema spreading over the precentral gyrus. There was no significant difference in the size, or the degree, of signal change between patients with or without compression or edema, nor between patients with and without preoperative motor impairment. During surgical intervention, displacement of the precentral gyrus was observed as had been demonstrated on preoperative images of patients. In all patients the precentral gyrus was preserved in all cases, and no deterioration of motor function occurred. Resolution of the displacement and edema was detected on postoperative MRI. Using the echo-planer technique on a clinical 1.0 T imager fMRI localization of the primary motor cortex was obtained in normal and brain tumor subjects. The activated areas were detected on the precentral gyrus of both groups, and even when there was marked brain compression or edema. It is important to identify and preserve the precentral gyrus during surgery to avoid deterioration of motor function. (K.H.)

  18. Definition of a magnetic susceptibility of conglomerates with magnetite particles. Particularities of defining single particle susceptibility

    Science.gov (United States)

    Sandulyak, A. A.; Sandulyak, A. V.; Ershova, V.; Pamme, N.; Ngmasom, B.; Iles, A.

    2017-11-01

    Data of a magnetic susceptibility of ferro-and the ferrimagnetic particles of many technogenic, natural, special media are especially demanded for the solution of various tasks connected with purposeful magnetic impact on these particles. One of productive approaches to definition of a magnetic susceptibility χ of these particles consists in receiving experimental data of a susceptibility of disperse samples 〈 χ 〉 with a disperse phase of these particles. The paper expounds and analyses the results of experiments on defining (by Faraday method in a magnetic field with intensity H = 90-730 kA/m) the magnetic susceptibility 〈 χ 〉 of disperse samples (conglomerates) with a given volume ratio γ of magnetite particles (γ = 0.0065-0.25). The corresponding families of concentration and field dependences are provided alongside with discussing the applicability of linear and exponential functions to describe these dependences. We consider the possibility of defining single particles susceptibility χ (with simultaneous obtaining field dependence of this susceptibility) by the commonly used relation χ = 〈 χ 〉 /γ both at relatively small (preferable for accuracy reasons) values γ - to γ = 0.02…0.025, as well as at increased values γ - up to γ = 0.25. The data χ are provided depending on H and correlating with known data at H matter magnetic susceptibility χm (for the case when the particles are traditionally likened to balls with the characteristic for them demagnetising factor equalling 1/3) complies with the anticipated inverse function χm ∼ 1/H in the studied area H (where magnetization M expressed as M = χH reaches saturation M = Const).

  19. Bacteriological Analysis, Antimicrobial Susceptibility and Detection of 16S rRNA gene of Helicobacter pylori by PCR in Drinking Water Samples of Earthquake Affected Areas and Other Parts of Pakistan

    Directory of Open Access Journals (Sweden)

    Rasheed, F.

    2009-01-01

    Full Text Available In Pakistan, clean drinking water is not available to most of the population. Main source of drinking water in Hazara, Azad Jammu and Kashmir-Pakistan is underground and spring water, due to earthquake water reservoirs in these areas were immensely contaminated. Moreover, drinking water treatment and proper sanitary facilities were also lacking. This study was conducted to analyze the quality of drinking water available in most of the cities of Pakistan including earthquake hit areas. For this purpose, 112 water samples were collected and analyzed by membrane filtration method. Microbial isolates were identified using QTS-10 and biochemical tests. Almost all samples were found to be contaminated but in earthquake affected areas quality of drinking water was substandard than other areas of Pakistan. Results revealed the detection of following bacterial pathogens among the water samples: Enterobacter sp., Klebsiellasp., Stenotrophomonas sp., Salmonella sp., Proteus sp., Edwardsiella tarda, Pseudomonas aeruginosa, Vibrio parahaemolyticus, Vibrio cholerae, Escherichia coli, Acinetobacter baumanii, Aeromonas hydrophila, Citrobacter freundii, Shigella dysenteriae, Staphylococcus aureus, Staphylococcus sp. and Streptococcus sp. Furthermore, these bacterial isolates were found to be resistant to ampicillin (32.1%, amoxicillin (30.4%, sulphometoxazole (20.5% and cefaclor (31.3%. All drinking water samples were analyzed for 16S rRNA gene of Helicobacter pylori by using PCR, however no positive result was found in these samples. Based on our results it is suggested that authorities should pay attention to supply safe water and proper sanitary facilities to avoid epidemics of infectious diseases in future.

  20. Brain Tumors

    Science.gov (United States)

    A brain tumor is a growth of abnormal cells in the tissues of the brain. Brain tumors can be benign, with no cancer cells, ... cancer cells that grow quickly. Some are primary brain tumors, which start in the brain. Others are ...

  1. Brain/MINDS: brain-mapping project in Japan

    Science.gov (United States)

    Okano, Hideyuki; Miyawaki, Atsushi; Kasai, Kiyoto

    2015-01-01

    There is an emerging interest in brain-mapping projects in countries across the world, including the USA, Europe, Australia and China. In 2014, Japan started a brain-mapping project called Brain Mapping by Integrated Neurotechnologies for Disease Studies (Brain/MINDS). Brain/MINDS aims to map the structure and function of neuronal circuits to ultimately understand the vast complexity of the human brain, and takes advantage of a unique non-human primate animal model, the common marmoset (Callithrix jacchus). In Brain/MINDS, the RIKEN Brain Science Institute acts as a central institute. The objectives of Brain/MINDS can be categorized into the following three major subject areas: (i) structure and functional mapping of a non-human primate brain (the marmoset brain); (ii) development of innovative neurotechnologies for brain mapping; and (iii) human brain mapping; and clinical research. Brain/MINDS researchers are highly motivated to identify the neuronal circuits responsible for the phenotype of neurological and psychiatric disorders, and to understand the development of these devastating disorders through the integration of these three subject areas. PMID:25823872

  2. Brain/MINDS: brain-mapping project in Japan.

    Science.gov (United States)

    Okano, Hideyuki; Miyawaki, Atsushi; Kasai, Kiyoto

    2015-05-19

    There is an emerging interest in brain-mapping projects in countries across the world, including the USA, Europe, Australia and China. In 2014, Japan started a brain-mapping project called Brain Mapping by Integrated Neurotechnologies for Disease Studies (Brain/MINDS). Brain/MINDS aims to map the structure and function of neuronal circuits to ultimately understand the vast complexity of the human brain, and takes advantage of a unique non-human primate animal model, the common marmoset (Callithrix jacchus). In Brain/MINDS, the RIKEN Brain Science Institute acts as a central institute. The objectives of Brain/MINDS can be categorized into the following three major subject areas: (i) structure and functional mapping of a non-human primate brain (the marmoset brain); (ii) development of innovative neurotechnologies for brain mapping; and (iii) human brain mapping; and clinical research. Brain/MINDS researchers are highly motivated to identify the neuronal circuits responsible for the phenotype of neurological and psychiatric disorders, and to understand the development of these devastating disorders through the integration of these three subject areas.

  3. Soil magnetic susceptibility as indicator of radioactive contamination

    International Nuclear Information System (INIS)

    Curda, S.

    2006-01-01

    Measurement of magnetic susceptibility is a method, which is used in many areas of research. The locality Ak-Tjuz is typical example of old ecological load. One of the negative effects represents radioactive contamination. This situation is caused by environmental disaster in 1964. For useful reparation it is really necessary to determinate the surface range of contamination. And measurement of the magnetic susceptibility could be the suitable method for that kind of monitoring. (author)

  4. Acupuncture at Waiguan (SJ5) and sham points influences activation of functional brain areas of ischemic stroke patients: a functional magnetic resonance imaging study

    OpenAIRE

    Qi, Ji; Chen, Junqi; Huang, Yong; Lai, Xinsheng; Tang, Chunzhi; Yang, Junjun; Chen, Hua; Qu, Shanshan

    2014-01-01

    Most studies addressing the specificity of meridians and acupuncture points have focused mainly on the different neural effects of acupuncture at different points in healthy individuals. This study examined the effects of acupuncture on brain function in a pathological context. Sixteen patients with ischemic stroke were randomly assigned to true point group (true acupuncture at right Waiguan (SJ5)) and sham point group (sham acupuncture). Results of functional magnetic resonance imaging revea...

  5. Perfusion imaging with magnetic-susceptibility contrast media

    International Nuclear Information System (INIS)

    Rosen, B.R.; Belliveau, J.W.; Betteridge, D.; Cohen, M.S.; Weisskoff, R.M.; Vevea, J.M.; Rzedzian, R.P.; Brady, T.J.

    1989-01-01

    In animal models, transient signal los on T2-weighted images has been well documented following intravenous injection of high-magnetic-susceptibility contrast agents that are compartmentalized within the brain intravascular space. These signal changes have been correlated with physiologic parameters, such as blood flow and volume. The advent of whole-body single-shot imaging capability, coupled with the approval of paramagnetic contrasts agents for human use, has enabled the authors to demonstrate susceptibility contrast in the human brain, allowing for generation of functional images. With use of a 1.5-T imaging system gradient-echo images (TE = 60 msec) were acquired in 75 msec. Sequential single-sections images were sampled every 1 second following bolus administration of 0.1 mmol/kg of Gd-DTPA

  6. Brain surgery

    Science.gov (United States)

    Craniotomy; Surgery - brain; Neurosurgery; Craniectomy; Stereotactic craniotomy; Stereotactic brain biopsy; Endoscopic craniotomy ... cut depends on where the problem in the brain is located. The surgeon creates a hole in ...

  7. Brain Malformations

    Science.gov (United States)

    Most brain malformations begin long before a baby is born. Something damages the developing nervous system or causes it ... medicines, infections, or radiation during pregnancy interferes with brain development. Parts of the brain may be missing, ...

  8. Democratic reinforcement: A principle for brain function

    International Nuclear Information System (INIS)

    Stassinopoulos, D.; Bak, P.

    1995-01-01

    We introduce a simple ''toy'' brain model. The model consists of a set of randomly connected, or layered integrate-and-fire neurons. Inputs to and outputs from the environment are connected randomly to subsets of neurons. The connections between firing neurons are strengthened or weakened according to whether the action was successful or not. Unlike previous reinforcement learning algorithms, the feedback from the environment is democratic: it affects all neurons in the same way, irrespective of their position in the network and independent of the output signal. Thus no unrealistic back propagation or other external computation is needed. This is accomplished by a global threshold regulation which allows the system to self-organize into a highly susceptible, possibly ''critical'' state with low activity and sparse connections between firing neurons. The low activity permits memory in quiescent areas to be conserved since only firing neurons are modified when new information is being taught

  9. Integration of landslide susceptibility products in the environmental plans

    Science.gov (United States)

    Fiorucci, Federica; Reichenbach, Paola; Rossi, Mauro; Cardinali, Mauro; Guzzetti, Fausto

    2015-04-01

    Landslides are one of the most destructive natural hazard that causes damages to urban area worldwide. The knowledge of where a landslide could occur is essential for the strategic management of the territory and for a good urban planning . In this contest landslide susceptibility zoning (LSZ) is crucial to provide information on the degree to which an area can be affected by future slope movements. Despite landslide susceptibility maps have been prepared extensively during the last decades, there are few examples of application is in the environmental plans (EP). In this work we present a proposal for the integration of the landslide inventory map with the following landslide susceptibility products: (i) landslide susceptibility zonation , (ii) the associated error map and (iii) the susceptibility uncertainty map. Moreover we proposed to incorporate detailed morphological studies for the evaluation of landslide risk associated to local parceling plan. The integration of all this information is crucial for the management of landslide risk in urban expansions forecasts. Municipality, province and regional administration are often not able to support the costs of landslide risk evaluation for extensive areas but should concentrate their financial resources to specific hazardous and unsafe situations defined by the result of the integration of landslide susceptibility products. Zonation and detail morphological analysis should be performed taking into account the existing laws and regulations, and could become a starting point to discuss new regulations for the landslide risk management.

  10. LANDSLIDE SUSCEPTIBILITY ASSESSMENT THROUGH FUZZY LOGIC INFERENCE SYSTEM (FLIS

    Directory of Open Access Journals (Sweden)

    T. Bibi

    2016-09-01

    Full Text Available Landslide is among one of the most important natural hazards that lead to modification of the environment. It is a regular feature of a rapidly growing district Mansehra, Pakistan. This caused extensive loss of life and property in the district located at the foothills of Himalaya. Keeping in view the situation it is concluded that besides structural approaches the non-structural approaches such as hazard and risk assessment maps are effective tools to reduce the intensity of damage. A landslide susceptibility map is base for engineering geologists and geomorphologists. However, it is not easy to produce a reliable susceptibility map due to complex nature of landslides. Since 1980s, several mathematical models have been developed to map landslide susceptibility and hazard. Among various models this paper is discussing the effectiveness of fuzzy logic approach for landslide susceptibility mapping in District Mansehra, Pakistan. The factor maps were modified as landslide susceptibility and fuzzy membership functions were assessed for each class. Likelihood ratios are obtained for each class of contributing factors by considering the expert opinion. The fuzzy operators are applied to generate landslide susceptibility maps. According to this map, 17% of the study area is classified as high susceptibility, 32% as moderate susceptibility, 51% as low susceptibility and areas. From the results it is found that the fuzzy model can integrate effectively with various spatial data for landslide hazard mapping, suggestions in this study are hope to be helpful to improve the applications including interpretation, and integration phases in order to obtain an accurate decision supporting layer.

  11. [Antimicrobial susceptibility in Chile 2012].

    Science.gov (United States)

    Cifuentes-D, Marcela; Silva, Francisco; García, Patricia; Bello, Helia; Briceño, Isabel; Calvo-A, Mario; Labarca, Jaime

    2014-04-01

    Bacteria antimicrobial resistance is an uncontrolled public health problem that progressively increases its magnitude and complexity. The Grupo Colaborativo de Resistencia, formed by a join of experts that represent 39 Chilean health institutions has been concerned with bacteria antimicrobial susceptibility in our country since 2008. In this document we present in vitro bacterial susceptibility accumulated during year 2012 belonging to 28 national health institutions that represent about 36% of hospital discharges in Chile. We consider of major importance to report periodically bacteria susceptibility so to keep the medical community updated to achieve target the empirical antimicrobial therapies and the control measures and prevention of the dissemination of multiresistant strains.

  12. The role of Abcb5 alleles in susceptibility to haloperidol-induced toxicity in mice and humans.

    KAUST Repository

    Zheng, Ming; Zhang, Haili; Dill, David L; Clark, J David; Tu, Susan; Yablonovitch, Arielle L; Tan, Meng How; Zhang, Rui; Rujescu, Dan; Wu, Manhong; Tessarollo, Lino; Vieira, Wilfred; Gottesman, Michael M; Deng, Suhua; Eberlin, Livia S; Zare, Richard N; Billard, Jean-Martin; Gillet, Jean-Pierre; Li, Jin Billy; Peltz, Gary

    2015-01-01

    that genetic variation within an ABC-drug efflux transporter (Abcb5) affected susceptibility to HIT. In situ hybridization results reveal that Abcb5 is expressed in brain capillaries, and by cerebellar Purkinje cells. We also analyzed chromosome substitution

  13. Discrimination between glioma grades II and III in suspected low-grade gliomas using dynamic contrast-enhanced and dynamic susceptibility contrast perfusion MR imaging

    DEFF Research Database (Denmark)

    Falk, Anna; Fahlström, Markus; Rostrup, Egill

    2014-01-01

    INTRODUCTION: Perfusion magnetic resonance imaging (MRI) can be used in the pre-operative assessment of brain tumours. The aim of this prospective study was to identify the perfusion parameters from dynamic contrast-enhanced (DCE) and dynamic susceptibility contrast (DSC) perfusion imaging...... written informed consent in this review board-approved study. Regions of interests (ROIs) in tumour area were delineated on FLAIR images co-registered to DCE and DSC, respectively, in 25 patients with histopathological grade II (n = 18) and III (n = 7) gliomas. Statistical analysis of differences between...

  14. A Comparison of Independent Event-Related Desynchronization Responses in Motor-Related Brain Areas to Movement Execution, Movement Imagery, and Movement Observation.

    Science.gov (United States)

    Duann, Jeng-Ren; Chiou, Jin-Chern

    2016-01-01

    Electroencephalographic (EEG) event-related desynchronization (ERD) induced by movement imagery or by observing biological movements performed by someone else has recently been used extensively for brain-computer interface-based applications, such as applications used in stroke rehabilitation training and motor skill learning. However, the ERD responses induced by the movement imagery and observation might not be as reliable as the ERD responses induced by movement execution. Given that studies on the reliability of the EEG ERD responses induced by these activities are still lacking, here we conducted an EEG experiment with movement imagery, movement observation, and movement execution, performed multiple times each in a pseudorandomized order in the same experimental runs. Then, independent component analysis (ICA) was applied to the EEG data to find the common motor-related EEG source activity shared by the three motor tasks. Finally, conditional EEG ERD responses associated with the three movement conditions were computed and compared. Among the three motor conditions, the EEG ERD responses induced by motor execution revealed the alpha power suppression with highest strengths and longest durations. The ERD responses of the movement imagery and movement observation only partially resembled the ERD pattern of the movement execution condition, with slightly better detectability for the ERD responses associated with the movement imagery and faster ERD responses for movement observation. This may indicate different levels of involvement in the same motor-related brain circuits during different movement conditions. In addition, because the resulting conditional EEG ERD responses from the ICA preprocessing came with minimal contamination from the non-related and/or artifactual noisy components, this result can play a role of the reference for devising a brain-computer interface using the EEG ERD features of movement imagery or observation.

  15. Ancestral susceptibility to colorectal cancer

    Czech Academy of Sciences Publication Activity Database

    Huhn, S.; Pardini, Barbara; Naccarati, Alessio; Vodička, Pavel (ed.); Hemminki, K.; Försti, A.

    2012-01-01

    Roč. 27, č. 2 (2012), s. 197-204 ISSN 0267-8357 R&D Projects: GA ČR GA310/07/1430; GA ČR GAP304/10/1286 Grant - others:EU FP7(XE) HEALTH-F4-2007-200767 Institutional research plan: CEZ:AV0Z50390512 Keywords : cancer susceptibility * molecular epidemiology * genetic susceptibility Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.500, year: 2012

  16. A case-control study of association between genetic polymorphisms of metabolizing enzymes GSTM1 and lung cancer susceptibility for the people living in high radon-exposed area

    International Nuclear Information System (INIS)

    Qi Xuesong; Lu Huimin; Xia Ying; Shang Bing; Sun Quanfu; Cui Hongxing; Wang Liping

    2009-01-01

    A case-control study was performed with 53 lung cancer patients and 72 frequency-matched controls to assess the role of genetic polymorphisms of metabolizing enzymes Glutathione S-transferases M1(GSTM1) in risk of developing lung cancer for the people living in high radon-exposed area. The associations between genotypes and risk of developing lung cancer were estimated by odds ratios (ORs) and their 95% confidence intervals (CIs) calculated by unconditional logistic regression. The frequencies of GSTM1 positive polymorphism and null polymorphism were 38.9% and 64.1% respectively in lung cancer patients. The frequencies of GSTM1 positive polymorphism and null polymorphism were 43.1% and 56.9% respectively in controls. The risk of developing lung cancer for GSTM1 null polymorphism was 1.35-fold(95%CI 0.652-2.81). GSTM1 null polymorphism with effective dose <50 mSv could increase the risk of developing lung cancer (OR 1.14, 95%CI 0.198-6.60). The frequency of GSTM1 positive polymorphism of lung cancer patients was lower than that of the controls. Based on those data, the frequency of GSTM1 null polymorphism of lung cancer patients was higher than that of the controls. There was an association between genetic polymorphism of GSTM1 and lung cancer. But the differences were not all statistically significant. (authors)

  17. Social instigation and repeated aggressive confrontations in male Swiss mice: analysis of plasma corticosterone, CRF and BDNF levels in limbic brain areas

    Directory of Open Access Journals (Sweden)

    Paula Madeira Fortes

    2017-06-01

    Full Text Available Abstract Introduction: Agonistic behaviors help to ensure survival, provide advantage in competition, and communicate social status. The resident-intruder paradigm, an animal model based on male intraspecific confrontations, can be an ethologically relevant tool to investigate the neurobiology of aggressive behavior. Objectives: To examine behavioral and neurobiological mechanisms of aggressive behavior in male Swiss mice exposed to repeated confrontations in the resident intruder paradigm. Methods: Behavioral analysis was performed in association with measurements of plasma corticosterone of mice repeatedly exposed to a potential rival nearby, but inaccessible (social instigation, or to 10 sessions of social instigation followed by direct aggressive encounters. Moreover, corticotropin-releasing factor (CRF and brain-derived neurotrophic factor (BNDF were measured in the brain of these animals. Control mice were exposed to neither social instigation nor aggressive confrontations. Results: Mice exposed to aggressive confrontations exhibited a similar pattern of species-typical aggressive and non-aggressive behaviors on the first and the last session. Moreover, in contrast to social instigation only, repeated aggressive confrontations promoted an increase in plasma corticosterone. After 10 aggressive confrontation sessions, mice presented a non-significant trend toward reducing hippocampal levels of CRF, which inversely correlated with plasma corticosterone levels. Conversely, repeated sessions of social instigation or aggressive confrontation did not alter BDNF concentrations at the prefrontal cortex and hippocampus. Conclusion: Exposure to repeated episodes of aggressive encounters did not promote habituation over time. Additionally, CRF seems to be involved in physiological responses to social stressors.

  18. N-acetylaspartate (NAA) levels in selected areas of the brain in patients with chronic schizophrenia treated with typical and atypical neuroleptics: a proton magnetic resonance spectroscopy (1H MRS) study.

    Science.gov (United States)

    Szulc, Agata; Galińska, Beata; Tarasów, Eugeniusz; Kubas, Bozena; Dzienis, Wojciech; Konarzewska, Beata; Poplawska, Regina; Tomczak, Anna A; Czernikiewicz, Andrzej; Walecki, Jerzy

    2007-05-01

    NAA, marker of neurons integrity and viability, is one of the most important brain metabolites visible in 1H MRS. In most studies of schizophrenia, the decrease of NAA level was observed in the temporal, frontal lobes and in the thalamus. This finding was observed more often among chronic patients, what suggests the influence of disease duration or the effect of neuroleptic treatment. The aim of the present study was the comparison of NAA levels in brain of schizophrenic patients taking typical and atypical neuroleptics. We analyzed the NAA levels in selected brain areas in 58 schizophrenic patients and 21 healthy controls. 10 patients were treated with typical neuroleptics, 10 patients with clozapine, 17 received olanzapine and 21 - risperidone. 1H MRS was performed on a 1,5 MR scanner with PRESS sequence. Voxels of 2x2x2 cm were localized in the left frontal, left temporal lobe and left thalamus. There were no differences in NAA levels between patients on typical and atypical medications analyzed together and separately (olanzapine, clozapine and risperidone groups). We also did not find any differences between patients taking selected atypical neuroleptics and controls. The NAA level in the thalamus in the group of patients receiving typical antipsychotics was the lowest among all groups and differed significantly from healthy controls. The results of our study suggest that atypical neuroleptics may have favorable effect on NAA concentration in brain of schizophrenic patients. Decrease in NAA level in patients taking typical medication may be caused by the progression of the disease or by the direct action of these drugs.

  19. Distribution of cellular HSV-1 receptor expression in human brain.

    Science.gov (United States)

    Lathe, Richard; Haas, Juergen G

    2017-06-01

    Herpes simplex virus type 1 (HSV-1) is a neurotropic virus linked to a range of acute and chronic neurological disorders affecting distinct regions of the brain. Unusually, HSV-1 entry into cells requires the interaction of viral proteins glycoprotein D (gD) and glycoprotein B (gB) with distinct cellular receptor proteins. Several different gD and gB receptors have been identified, including TNFRSF14/HVEM and PVRL1/nectin 1 as gD receptors and PILRA, MAG, and MYH9 as gB receptors. We investigated the expression of these receptor molecules in different areas of the adult and developing human brain using online transcriptome databases. Whereas all HSV-1 receptors showed distinct expression patterns in different brain areas, the Allan Brain Atlas (ABA) reported increased expression of both gD and gB receptors in the hippocampus. Specifically, for PVRL1, TNFRFS14, and MYH9, the differential z scores for hippocampal expression, a measure of relative levels of increased expression, rose to 2.9, 2.9, and 2.5, respectively, comparable to the z score for the archetypical hippocampus-enriched mineralocorticoid receptor (NR3C2, z = 3.1). These data were confirmed at the Human Brain Transcriptome (HBT) database, but HBT data indicate that MAG expression is also enriched in hippocampus. The HBT database allowed the developmental pattern of expression to be investigated; we report that all HSV1 receptors markedly increase in expression levels between gestation and the postnatal/adult periods. These results suggest that differential receptor expression levels of several HSV-1 gD and gB receptors in the adult hippocampus are likely to underlie the susceptibility of this brain region to HSV-1 infection.

  20. Inadequate Brain Glycogen or Sleep Increases Spreading Depression Susceptibility

    KAUST Repository

    Kilic, Kivilcim; Karatas, Hulya; Donmez-Demir, Buket; Eren-Kocak, Emine; Gursoy-Ozdemir, Yasemin; Can, Alp; Petit, Jean-Marie; Magistretti, Pierre J.; Dalkara, Turgay

    2017-01-01

    Glycogen in astrocyte endfeet contributes to maintenance of low extracellular glutamate and K+ concentrations around synapses. Sleep deprivation (SD), a common migraine trigger induces transcriptional changes in astrocytes reducing glycogen breakdown. We hypothesize that when glycogen utilization cannot match synaptic energy demand, extracellular K+ can rise to levels that activate neuronal pannexin-1 channels and downstream inflammatory pathway, which might be one of the mechanisms initiating migraine headaches.We suppressed glycogen breakdown by inhibiting glycogen phosphorylation with 1,4-dideoxy-1,4-imino-D-arabinitol (DAB) and by SD.DAB caused neuronal pannexin-1 large-pore opening and activation of the downstream inflammatory pathway as shown by procaspase-1 cleavage and HMGB1 release from neurons. Six-hour SD induced pannexin-1 mRNA. DAB and SD also lowered the cortical spreading depression (CSD) induction threshold, which was reversed by glucose or lactate supplement, suggesting that glycogen-derived energy substrates are needed to prevent CSD generation. Supporting this, knocking-down neuronal lactate transporter, MCT2 with an anti-sense oligonucleotide or inhibiting glucose transport from vessels to astrocytes with intracerebroventricularly given phloretin reduced the CSD threshold. In vivo recordings with a K+ -sensitive/selective fluoroprobe, APG-4 disclosed that DAB treatment or SD caused significant rise in extracellular K+ during whisker-stimulation, illustrating the critical role of glycogen in extracellular K+ clearance.Synaptic metabolic stress caused by insufficient glycogen-derived energy substrate supply can activate neuronal pannexin-1 channels as well as lowering the CSD threshold. Therefore, conditions that limit energy supply to synapse (e.g. SD) may predispose to migraine attacks as suggested by genetic studies associating glucose or lactate transporter deficiency with migraine. This article is protected by copyright. All rights reserved.

  1. Inadequate Brain Glycogen or Sleep Increases Spreading Depression Susceptibility

    KAUST Repository

    Kilic, Kivilcim

    2017-12-16

    Glycogen in astrocyte endfeet contributes to maintenance of low extracellular glutamate and K+ concentrations around synapses. Sleep deprivation (SD), a common migraine trigger induces transcriptional changes in astrocytes reducing glycogen breakdown. We hypothesize that when glycogen utilization cannot match synaptic energy demand, extracellular K+ can rise to levels that activate neuronal pannexin-1 channels and downstream inflammatory pathway, which might be one of the mechanisms initiating migraine headaches.We suppressed glycogen breakdown by inhibiting glycogen phosphorylation with 1,4-dideoxy-1,4-imino-D-arabinitol (DAB) and by SD.DAB caused neuronal pannexin-1 large-pore opening and activation of the downstream inflammatory pathway as shown by procaspase-1 cleavage and HMGB1 release from neurons. Six-hour SD induced pannexin-1 mRNA. DAB and SD also lowered the cortical spreading depression (CSD) induction threshold, which was reversed by glucose or lactate supplement, suggesting that glycogen-derived energy substrates are needed to prevent CSD generation. Supporting this, knocking-down neuronal lactate transporter, MCT2 with an anti-sense oligonucleotide or inhibiting glucose transport from vessels to astrocytes with intracerebroventricularly given phloretin reduced the CSD threshold. In vivo recordings with a K+ -sensitive/selective fluoroprobe, APG-4 disclosed that DAB treatment or SD caused significant rise in extracellular K+ during whisker-stimulation, illustrating the critical role of glycogen in extracellular K+ clearance.Synaptic metabolic stress caused by insufficient glycogen-derived energy substrate supply can activate neuronal pannexin-1 channels as well as lowering the CSD threshold. Therefore, conditions that limit energy supply to synapse (e.g. SD) may predispose to migraine attacks as suggested by genetic studies associating glucose or lactate transporter deficiency with migraine. This article is protected by copyright. All rights reserved.

  2. The effect of amperozide on uptake and release of [3H]-dopamine in vitro from perfused rat striatal and limbic brain areas

    International Nuclear Information System (INIS)

    Eriksson, E.; Christensson, E.

    1990-01-01

    Amperozide, a putatively antipsychotic drug, was studied for its effects on uptake and release of [ 3 H]-dopamine in rat brain in vitro. Amperozide inhibited uptake of [ 3 H]-dopamine in striatal chopped tissue in vitro with an IC 50 of 18 μM. It also increased basal release of [ 3 H]-dopamine from perfused rat striatal and limbic tissue in vitro at concentrations above 5 μM. Release of [ 3 H]-dopamine from perfused rat striatal and limbic tissue stimulated with 5 μM amphetamine, was inhibited by 1 μM amperozide to 46%. No significant difference was found for the effect of amperozide on in vitro release of [ 3 H]-dopamine from corpus striatum compared to tissue from limbic grain regions; neither on basal release nor on amphetamine-stimulated release of dopamine. (author)

  3. Susceptibility Genes in Thyroid Autoimmunity

    Directory of Open Access Journals (Sweden)

    Yoshiyuki Ban

    2005-01-01

    Full Text Available The autoimmune thyroid diseases (AITD are complex diseases which are caused by an interaction between susceptibility genes and environmental triggers. Genetic susceptibility in combination with external factors (e.g. dietary iodine is believed to initiate the autoimmune response to thyroid antigens. Abundant epidemiological data, including family and twin studies, point to a strong genetic influence on the development of AITD. Various techniques have been employed to identify the genes contributing to the etiology of AITD, including candidate gene analysis and whole genome screening. These studies have enabled the identification of several loci (genetic regions that are linked with AITD, and in some of these loci, putative AITD susceptibility genes have been identified. Some of these genes/loci are unique to Graves' disease (GD and Hashimoto's thyroiditis (HT and some are common to both the diseases, indicating that there is a shared genetic susceptibility to GD and HT. The putative GD and HT susceptibility genes include both immune modifying genes (e.g. HLA, CTLA-4 and thyroid specific genes (e.g. TSHR, Tg. Most likely, these loci interact and their interactions may influence disease phenotype and severity.

  4. Mapping Landslides Susceptibility in a Traditional Northern Nigerian City

    Science.gov (United States)

    Oluwafemi, Olawale A.; Yakubu, Tahir A.; Muhammad, Mahmud U.; Shitta, Nyofo; Akinwumiju, Akinola S.

    2018-05-01

    As a result of dearth of relevant information about Landslides Susceptibility in Nigeria, the monitoring and assessment appears intractable. Hence, the study developed a Remote Sensing approach to mapping landslides susceptibility, landuse and landcover analysis in Jos South LGA, Plateau State, Nigeria. Field Observation, SPOT 5 2009 and 2012, ASTER DEM 2009, Geological Map 2006, Topographical Map 1966 were used to map Landslide Susceptibility and Landuse /Lancover Analysis in the study area. Geospatial Analytical Operations employed using ArcGIS 10.3 and Erdas Imagine 2014 include Spatial Modeling, Vectorization, Pre-lineament Extraction, Image Processing among others. Result showed that 72.38 % of the study area is underlain by granitic rocks. The landuse/cover types delineated for the study area include floodplain (29.27 %), farmland (23.96 %), sparsely vegetated land (15.43 %), built up area (13.65 %), vegetated outcrop (8.48 %), light vegetation (5.37 %), thick vegetation (2.39 %), water body (0.58 %), plantation (0.50 %) and mining pond (0.37 %). Landslide Susceptibility Analysis also revealed that 87 % of the study area is relatively at low to very low risk of landslide event. While only 13 % of the study area is at high to very high risk of landslide event. The study revealed that the susceptibility of landslide event is very low in the study area. However, possible landslide event in the hot spots could be pronounced and could destabilize the natural and man-made environmental systems of the study area.

  5. Clay mineralogy and magnetic susceptibility of Oxisols in geomorphic surfaces

    Directory of Open Access Journals (Sweden)

    Livia Arantes Camargo

    2014-06-01

    Full Text Available Studies analyzing the variability of clay minerals and magnetic susceptibility provide data for the delineation of site-specific management areas since many of their attributes are important to agronomy and the environment. This study aimed to evaluate the spatial variability of clay minerals, magnetic susceptibility, adsorbed phosphorus and physical attributes in Oxisols of sandstones in different geomorphic surfaces. For that purpose, soil samples were collected every 25 m along a transect located within the area where the geomorphic surfaces were identified and mapped. The transect occupied the central portion of 500 ha, where it was also sampled for density purposes with one sample per six hectares. Soil samples were collected at a depth of 0.0-0.2 m. The results of the physical, chemical, mineralogical and magnetic susceptibility analyses were subjected to statistical and geostatistical analyses. The nature of the clay minerals and magnetic susceptibility was dependent on the variation of the soil parent material. High values of magnetic susceptibility were associated with the presence of maghemite and magnetite of coarse size. The spatial variability of crystallinity and the content of Fe oxides, as well as magnetic susceptibility, were dependent on the age of the geomorphic surfaces. The youngest surface had greater spatial variability of these attributes. The iron (goethite and hematite and aluminum (gibbsite oxides in the youngest geomorphic surface influenced the low values of soil density and high values of total pore volume, micropores and P adsorption. The characterization of the spatial variability of Fe oxides and susceptibility allowed for the delineation of homogeneous areas.

  6. Topological susceptibility from the overlap

    DEFF Research Database (Denmark)

    Del Debbio, Luigi; Pica, Claudio

    2003-01-01

    The chiral symmetry at finite lattice spacing of Ginsparg-Wilson fermionic actions constrains the renormalization of the lattice operators; in particular, the topological susceptibility does not require any renormalization, when using a fermionic estimator to define the topological charge....... Therefore, the overlap formalism appears as an appealing candidate to study the continuum limit of the topological susceptibility while keeping the systematic errors under theoretical control. We present results for the SU(3) pure gauge theory using the index of the overlap Dirac operator to study...

  7. MAPEAMENTO DAS ÁREAS SUSCETÍVEIS À EROSÃO HÍDRICA NOS MUNICÍPIOS DE CALDAS NOVAS, NOVA AMÉRICA E RIO QUENTE (GO MAPPING THE EROSION SUSCEPTIBLE AREAS OF CALDAS NOVAS, NOVA AMÉRICA AND RIO QUENTE, GOIÁS - BRASIL

    Directory of Open Access Journals (Sweden)

    Luiz Fernando Coutinho de Oliveira

    2007-09-01

    Full Text Available

    A importância de mapear as áreas suscetíveis à erosão hídrica nos municípios de Caldas Novas, Nova América e Rio Quente deve-se ao fato de que eles apresentaram os maiores índices de precipitação pluviométrica e pelo potencial que os mesmos representam para o estado de Goiás, principalmente o turístico. Na elaboração desses mapas, estabeleceram-se preliminarmente os planos de informação referentes às classes de solo, à declividade e ao uso do solo através de digitalização, empregando o software SGI/INPE, e a espacialização da intensidade de precipitação com duração de 30 minutos sobre a base cartográfica dos municípios, obtendo assim os mapas temáticos. Através do cruzamento dos mapas temáticos, foram classificadas e mapeadas as áreas suscetíveis à erosão hídrica. A metodologia empregada mostrou-se satisfatória, permitindo gerar os mapas temáticos das áreas suscetíveis à erosão hídrica nos municípios estudados que servirão de orientação para os trabalhos de campo.

    PALAVRAS-CHAVE: Erosão; sistema de informação geográfica; conservação do solo.

    The importance of mapping the erosion susceptible areas of Caldas Novas, Nova América and Rio Quente is that these municipalities present high rainfall rates and the potential they represent for the Goiás state, mostly for tourism. As a preliminary to elaborate these maps the soil type, slope and use of classes information were planned through digitalization using the SGI/INPE software, and a spatialization of the 30 minutes rainfall intensity over the municipalities cartographic base, obtaining the thematic maps. Through thematic maps crossing, the erosion susceptible areas were classified and mapped. The methodology used was considered satisfactory and generated the thematic

  8. FLOOD SUSCEPTIBILITY ASSESSMENT IN THE NIRAJ BASIN

    Directory of Open Access Journals (Sweden)

    SANDA ROŞCA

    2012-03-01

    Full Text Available Flood susceptibility assessment in the Niraj basin. In the context of global warming and the increasing frequency of extreme weather events, it becomes evident that we have to face natural hazards, such as floods. In the area of Niraj basin this phenomenon is specific both in the spring, because of the snow melting and of the precipitations which come along with the season, and then in the summer because of the torrential precipitations but rarely in autumn and winter. The aim of this paper is to determinate the susceptibility of the zone and obtain a map which will take into consideration the possibility of a flooding. Defining vulnerability can help us understand this type of natural disasters and find the best ways to reduce it. For this purpose we use thematic layers, morphological characteristics (slope and depth fragmentation, hydrological characteristics, geology, pedology (permeability and soil texture, landuse, precipitation data, and human interventions because in this way we have the possibility to use data mining for this purpose. Data mining will allow us to extract new information based on the existing sets of data.The final result will be a thematic map that highlights the areas which are exposed to the flood. Therefore, this map can be used as a support decision for local government or business purposes.

  9. Study of cerebral blood flow and oxygen utilization in the edematous area and ipsilateral hemispheric gray matter using positron emission tomography in brain tumors

    International Nuclear Information System (INIS)

    Ikeda, Yusuke

    1990-01-01

    We measured the cerebral blood flow and oxygen utilization of the peritumoral white matter and ipsilateral hemispheric gray matter in 50 patients with brain tumors using Positron Emission Tomography (PET). The intraaxial tumors consisted of 34 cases (25 of gliomas, 6 of metastatic tumors, and 3 others), white the extraaxial tumors (all of meningiomas) were 16 cases. The cases were divided into 2 groups on the basis of the Xray CT scan findings. The cases of Edema (+) group showed moderate or large peritumoral edema in the white matter on the Xray CT scan, while Edema (-) group showed no or small edema. The method of PET study was the 15 O steady state inhalation technique by Frackoviak's method. ROIs (region of interest) were set on the peritumoral white matter and the ipsilateral hemispheric gray matter, and the mean CBF, OEF and CMRO2 values of the white and gray matter were calculated. In the Edema (+) group, the mean values of blood flow and oxygen utilization were low in the peritumoral white matter, and there were no obvious differences of values between intra and extraaxial tumors. But, the values in the ipsilateral hemispheric gray matter of intraaxial tumors were lower than those of extraaxial tumor. In the Edema (-) group, the mean values were almost normal in the white and gray matter, and there were no differences between intra and extraaxial tumors. The consideration about significance of the above stated results was discussed added with literature. (author)

  10. Meta-analysis of diffusion tensor imaging (DTI) studies shows altered fractional anisotropy occurring in distinct brain areas in association with depression

    LENUS (Irish Health Repository)

    Murphy, Melissa L

    2011-09-27

    Abstract Fractional anisotropy anomalies occurring in the white matter tracts in the brains of depressed patients may reflect microstructural changes underlying the pathophysiology of this disorder. We conducted a meta-analysis of fractional anisotropy abnormalities occurring in major depressive disorder using voxel-based diffusion tensor imaging studies. Using the Embase, PubMed and Google Scholar databases, 89 relevant data sets were identified, of which 7 (including 188 patients with major depressive disorder and 221 healthy controls) met our inclusion criteria. Authors were contacted to retrieve any additional data required. Coordinates were extracted from clusters of significant white matter fractional anisotropy differences between patients and controls. Relevant demographic, clinical and methodological variables were extracted from each study or obtained directly from authors. The meta-analysis was carried out using Signed Differential Mapping. Patients with depression showed decreased white matter fractional anisotropy values in the superior longitudinal fasciculus and increased fractional anisotropy values in the fronto-occipital fasciculus compared to controls. Using quartile and jackknife sensitivity analysis, we found that reduced fractional anisotropy in the left superior longitudinal fasciculus was very stable, with increases in the right fronto-occipital fasciculus driven by just one study. In conclusion, our meta-analysis revealed a significant reduction in fractional anisotropy values in the left superior longitudinal fasciculus, which may ultimately play an important role in the pathology of depression.

  11. Meta-analysis of diffusion tensor imaging studies shows altered fractional anisotropy occurring in distinct brain areas in association with depression.

    LENUS (Irish Health Repository)

    Murphy, Melissa L

    2011-09-01

    Fractional anisotropy anomalies occurring in the white matter tracts in the brains of depressed patients may reflect microstructural changes underlying the pathophysiology of this disorder. We conducted a meta-analysis of fractional anisotropy abnormalities occurring in major depressive disorder using voxel-based diffusion tensor imaging studies. Using the Embase, PubMed and Google Scholar databases, 89 relevant data sets were identified, of which 7 (including 188 patients with major depressive disorder and 221 healthy controls) met our inclusion criteria. Authors were contacted to retrieve any additional data required. Coordinates were extracted from clusters of significant white matter fractional anisotropy differences between patients and controls. Relevant demographic, clinical and methodological variables were extracted from each study or obtained directly from authors. The meta-analysis was carried out using Signed Differential Mapping. Patients with depression showed decreased white matter fractional anisotropy values in the superior longitudinal fasciculus and increased fractional anisotropy values in the fronto-occipital fasciculus compared to controls. Using quartile and jackknife sensitivity analysis, we found that reduced fractional anisotropy in the left superior longitudinal fasciculus was very stable, with increases in the right fronto-occipital fasciculus driven by just one study. In conclusion, our meta-analysis revealed a significant reduction in fractional anisotropy values in the left superior longitudinal fasciculus, which may ultimately play an important role in the pathology of depression.

  12. Fos Protein Expression in Olfactory-Related Brain Areas after Learning and after Reactivation of a Slowly Acquired Olfactory Discrimination Task in the Rat

    Science.gov (United States)

    Roullet, Florence; Lienard, Fabienne; Datiche, Frederique; Cattarelli, Martine

    2005-01-01

    Fos protein immunodetection was used to investigate the neuronal activation elicited in some olfactory-related areas after either learning of an olfactory discrimination task or its reactivation 10 d later. Trained rats (T) progressively acquired the association between one odor of a pair and water-reward in a four-arm maze. Two groups of…

  13. Dynamic functional brain connectivity for face perception

    NARCIS (Netherlands)

    Yang, Yuan; Qiu, Yihong; Schouten, Alfred C.

    2015-01-01

    Face perception is mediated by a distributed brain network comprised of the core system at occipito-temporal areas and the extended system at other relevant brain areas involving bilateral hemispheres. In this study we explored how the brain connectivity changes over the time for face-sensitive

  14. Intraoperative appearance of the resection area in brain-tumor operations in an open 0,5 MRT; Intraoperatives Erscheinungsbild des Resektionsbereichs bei Hirntumoroperationen in einem offenen 0,5-T-MRT

    Energy Technology Data Exchange (ETDEWEB)

    Dietrich, J. [Universitaetsklinik fuer Diagnostische Radiologie, Leipzig (Germany). Arbeitsbereich Neuroradiologie; Schneider, J.P.; Schulz, T. [Universitaetsklinik fuer Diagnostische Radiologie, Leipzig (Germany); Seifert, V.; Trantakis, C. [Universitaetsklinik fuer Neurochirurgie, Leipzig (Germany); Kellermann, S. [Leipzig Univ. (Germany). Abt. fuer Neuropathologie

    1998-11-01

    During MRI-controlled resection of brain tumors using an open MRI system, operation-induced alterations may occur, especially enhancement of the resection cavity wall. This may simulate tumor areas, resulting in false assessment of the resection or resection of non-tumorous areas. Based on 42 MRI- and biopsy-controlled brain tumor resections in an 0.5 T open MRI (Signa SP, GE), the appearance and origin of operation-induced reactions are analyzed. In our opinion, there is a superposition of preformed peritumoral reactions by operation-induced microcontusions. The beginning of the cavity wall enhancement needs at least 10-15 min. MRI-controlled analysis of the intraoperative steps by the neurosurgeon and neuroradiologist allows discrimination of operation-induced reactions from tumor areas and leads to safe operation. (orig.) [Deutsch] Bei der intraoperativen Kontrolle von Hirntumorresektionen in offenen MRT-Geraeten kann es zu operativ induzierten Veraenderungen, insbesondere Rand-enhancement-Zonen, kommen. Diese koennen Tumorreste vortaeuschen, so dass die Radikalitaet des Eingriffs unterschaetzt wird oder nicht tumortragende Hirnareale entfernt werden. Ergebnisse und Diskussion: Anhand von 42 in einem offenen 0,5-T-MRT (Signa SP, GE) vorgenommenen, biopsiekontrollierten Hirntumoroperationen werden Erscheinungsbild und Entstehungsweise der Randveraenderungen analysiert. Bei den haeufig vorzufindenden Rand-enhancement-Zonen handelt es sich um eine Ueberlagerung von praeformierten Tumorrandreaktionen mit Mikrokontusionen. Die Ausbildung dieser Veraenderungen braucht eine Mindestzeit von 10-15 min. Die staendige Analyse der die Tumorresektion begleitenden MRT-Kontrollen durch den Operateur und einen mit der Problematik vertrauten Radiologen gestattet in der Regel die Differenzierung der operativ induzierten Veraenderungen und erhoeht damit die Sicherheit des Eingriffs. (orig.)

  15. Global stability of a susceptible-infected-susceptible epidemic model on networks with individual awareness

    International Nuclear Information System (INIS)

    Li Ke-Zan; Xu Zhong-Pu; Zhu Guang-Hu; Ding Yong

    2014-01-01

    Recent research results indicate that individual awareness can play an important influence on epidemic spreading in networks. By local stability analysis, a significant conclusion is that the embedded awareness in an epidemic network can increase its epidemic threshold. In this paper, by using limit theory and dynamical system theory, we further give global stability analysis of a susceptible-infected-susceptible (SIS) epidemic model on networks with awareness. Results show that the obtained epidemic threshold is also a global stability condition for its endemic equilibrium, which implies the embedded awareness can enhance the epidemic threshold globally. Some numerical examples are presented to verify the theoretical results. (interdisciplinary physics and related areas of science and technology)

  16. In vitro susceptibilities of Brucella melitensis isolates to eleven antibiotics

    Directory of Open Access Journals (Sweden)

    Loukaides Feidias

    2006-10-01

    Full Text Available Abstract Background Brucellosis is an endemic disease present in many countries worldwide, but it is rare in Europe and North America. Nevertheless brucella is included in the bacteria potentially used for bioterrorism. The aim of this study was the investigation of the antibiotic susceptibility profile of brucella isolates from areas of the eastern Mediterranean where it has been endemic. Methods The susceptibilities of 74 Brucella melitensis isolates derived from clinical samples (57 and animal products (17 were tested in vitro. The strains originate from Crete (59, Cyprus (10, and Syria (5. MICs of tetracycline, rifampicin, streptomycin, gentamicin, norfloxacin, ciprofloxacin, levofloxacin, trimethoprim/sulfamethoxazole, ampicillin, amoxicillin/clavulanic acid, and erythromycin were detected by E-test method. The NCCLS criteria for slow growing bacteria were considered to interpret the results. Results All the isolates were susceptible to tetracycline, streptomycin, gentamicin, ciprofloxacin, norfloxacin, and levofloxacin. Two isolates presented reduced susceptibility to rifampicin (MIC value: 1.5 mg/l and eight to SXT (MIC values: 0.75–1.5 mg/l. Erythromycin had the highest (4 mg/l MIC90value and both norfloxacin and erythromycin the highest (1.5 mg/l MIC50 value. Conclusion Brucella isolates remain susceptible in vitro to most antibiotics used for treatment of brucellosis. The establishment of a standardized antibiotic susceptibility method for Brucella spp would be useful for resistance determination in these bacteria and possible evaluation of bioterorism risks.

  17. Effects of Inventory Bias on Landslide Susceptibility Calculations

    Science.gov (United States)

    Stanley, T. A.; Kirschbaum, D. B.

    2017-01-01

    Many landslide inventories are known to be biased, especially inventories for large regions such as Oregon's SLIDO or NASA's Global Landslide Catalog. These biases must affect the results of empirically derived susceptibility models to some degree. We evaluated the strength of the susceptibility model distortion from postulated biases by truncating an unbiased inventory. We generated a synthetic inventory from an existing landslide susceptibility map of Oregon, then removed landslides from this inventory to simulate the effects of reporting biases likely to affect inventories in this region, namely population and infrastructure effects. Logistic regression models were fitted to the modified inventories. Then the process of biasing a susceptibility model was repeated with SLIDO data. We evaluated each susceptibility model with qualitative and quantitative methods. Results suggest that the effects of landslide inventory bias on empirical models should not be ignored, even if those models are, in some cases, useful. We suggest fitting models in well-documented areas and extrapolating across the study region as a possible approach to modeling landslide susceptibility with heavily biased inventories.

  18. Identification of seismically susceptible areas in western Himalaya ...

    Indian Academy of Sciences (India)

    Earthquakes cause tremendous loss of life and to the built environment. The amount of ... and reasonable decisions about categories of pat- terns. The main .... tion data. A classification criterion was formulated and tested. Seismicity data was compiled from var- ious earthquake catalogues, tectonic data was stud- ied and ...

  19. Brain Diseases

    Science.gov (United States)

    The brain is the control center of the body. It controls thoughts, memory, speech, and movement. It regulates the function of many organs. When the brain is healthy, it works quickly and automatically. However, ...

  20. Psychotherapy, consciousness, and brain plasticity

    Directory of Open Access Journals (Sweden)

    Daniel eCollerton

    2013-09-01

    Full Text Available Purely psychological treatments for emotional distress produce lasting, measureable, and reproducible changes in cognitive and emotional consciousness and brain function. How these changes come about illustrates the interplay between brain and consciousness. Studies of the effects of psychotherapy highlight the holistic nature of consciousness. Pre and post treatment functional Magnetic Resonance Imaging localises the brain changes following psychotherapy to frontal, cingulate, and limbic circuits, but emphasise that these areas support a wide range of conscious experiences. Multivoxel Pattern Analysis of distributed changes in function across these brain areas may be able to provide the ability to distinguish between different states of consciousness.

  1. Correlation between special brain area and blood perfusion in patients with cerebral infarction at convalescent period Feasibility for quantitative determination and estimation of learning and memory function

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    BACKGROUND: Presently, clinic memory scale is used to evaluate learning memory ability in most studies,and the influence of difference in measurement condition of individuals exists.OBJECTIVE: To study the correlation between regional cerebral blood flow (rCBF) perfusion and learning memory function in special brain regions of patients with cerebral infarction at convalescent period,and to try to find out a method which can quantitatively evaluate learning ability.DESIGN: Case observation, and correlation analysis.SETTINGS: Shandong Institute for Behavioral Medicine; the Affiliated Hospital of Jining Medical College.PARTICIPANTS: Totally 70 patients with cerebral infarction admitted to Departtment of Neurology, Jining Medical College between January 2004 and December 2005 were involved. The involved patients, 58 male and 12 female, were averaged (52±3) years, and they were all right handed. They all met the diagnosis criteria instituted by the Fourth National Conference on Cerebrovascular Disease, and were confirmed as cerebral infarction by skull CT or MRI. Informed consents of detected items were obtained from all the patients and relatives.METHODS: When the patients were at convalescent period, their learning and memory ability were measured with" clinic memory scale (set A)". The 18 patients whose total mark over 100 were regarded as good learning memory function group; The 23 cases whose total mark less than 70 were regarded as poor learning memory function group. RCBF of hippocampus, nucleus amygdalae, temporal cortex and prefrontal lobe of patients between two groups were measured and compared by single photon emission computed tomography (SPECT). The total scores of the 18 good learning memory patients and 23 poor learning memory patients were taken as dependent variable Y, and their rCBFs of hippocampus, nucleus amygdale,temporal cortex and prefrontal lobe respectively as independent variable X for linear correlation analysis.MAIN OUTCOME MEASURES

  2. Effect of Different Forms of Hypokinesia on the Ultrastructure of Limbic, Extrapyramidal and Neocortical Areas of the Rat Brain: Electron Microscopic Study

    Science.gov (United States)

    Zhvania, Mzia G.; Japaridze, Nadezhda J.; Ksovreli, Mariam G.

    The effect of chronic restraint stress and chronic hypokinesia "without stress" on the ultrastructure of central and lateral nuclei of amygdala, CA1 and CA3 area of the hippocampus, cingular cortex, nucleus caudatus and motor cortex of adult male rats were elucidated. In some neurons and synapses of abovementioned regions pathological modifications were revealed. More significant alterations provokes chronic restraint stress. Alterations are mostly concentrated: first—in the nuclei of amygdala, then in the CA1 and CA3 areas. Moderate alterations were observed in cingular cortex and nucleus caudatus. In comparing with it, hypokinesia "without stress" provokes only moderate modifications: predominantly in the nucleus caudatus, in lesser degree—in the hippocampus and amygdalae.

  3. Role of Estrogen and Other Sex Hormones in Brain Aging. Neuroprotection and DNA Repair

    Science.gov (United States)

    Zárate, Sandra; Stevnsner, Tinna; Gredilla, Ricardo

    2017-01-01

    Aging is an inevitable biological process characterized by a progressive decline in physiological function and increased susceptibility to disease. The detrimental effects of aging are observed in all tissues, the brain being the most important one due to its main role in the homeostasis of the organism. As our knowledge about the underlying mechanisms of brain aging increases, potential approaches to preserve brain function rise significantly. Accumulating evidence suggests that loss of genomic maintenance may contribute to aging, especially in the central nervous system (CNS) owing to its low DNA repair capacity. Sex hormones, particularly estrogens, possess potent antioxidant properties and play important roles in maintaining normal reproductive and non-reproductive functions. They exert neuroprotective actions and their loss during aging and natural or surgical menopause is associated with mitochondrial dysfunction, neuroinflammation, synaptic decline, cognitive impairment and increased risk of age-related disorders. Moreover, loss of sex hormones has been suggested to promote an accelerated aging phenotype eventually leading to the development of brain hypometabolism, a feature often observed in menopausal women and prodromal Alzheimer’s disease (AD). Although data on the relation between sex hormones and DNA repair mechanisms in the brain is still limited, various investigations have linked sex hormone levels with different DNA repair enzymes. Here, we review estrogen anti-aging and neuroprotective mechanisms, which are currently an area of intense study, together with the effect they may have on the DNA repair capacity in the brain. PMID:29311911

  4. Role of Estrogen and Other Sex Hormones in Brain Aging. Neuroprotection and DNA Repair

    Directory of Open Access Journals (Sweden)

    Sandra Zárate

    2017-12-01

    Full Text Available Aging is an inevitable biological process characterized by a progressive decline in physiological function and increased susceptibility to disease. The detrimental effects of aging are observed in all tissues, the brain being the most important one due to its main role in the homeostasis of the organism. As our knowledge about the underlying mechanisms of brain aging increases, potential approaches to preserve brain function rise significantly. Accumulating evidence suggests that loss of genomic maintenance may contribute to aging, especially in the central nervous system (CNS owing to its low DNA repair capacity. Sex hormones, particularly estrogens, possess potent antioxidant properties and play important roles in maintaining normal reproductive and non-reproductive functions. They exert neuroprotective actions and their loss during aging and natural or surgical menopause is associated with mitochondrial dysfunction, neuroinflammation, synaptic decline, cognitive impairment and increased risk of age-related disorders. Moreover, loss of sex hormones has been suggested to promote an accelerated aging phenotype eventually leading to the development of brain hypometabolism, a feature often observed in menopausal women and prodromal Alzheimer’s disease (AD. Although data on the relation between sex hormones and DNA repair mechanisms in the brain is still limited, various investigations have linked sex hormone levels with different DNA repair enzymes. Here, we review estrogen anti-aging and neuroprotective mechanisms, which are currently an area of intense study, together with the effect they may have on the DNA repair capacity in the brain.

  5. Prion protein and scrapie susceptibility

    NARCIS (Netherlands)

    Smits, M.A.; Bossers, A.; Schreuder, B.E.C.

    1997-01-01

    This article presents briefly current views on the role of prion protein (PrP) in Transmissible Spongiform Encephalopathies or prion diseases and the effect of PrP polymoryhisms on the susceptibility to these diseases, with special emphasis on sheep scrapie. The PrP genotype of sheep apears to be a

  6. Antifungal susceptibilities of Cryptococcus neoformans.

    Science.gov (United States)

    Archibald, Lennox K; Tuohy, Marion J; Wilson, Deborah A; Nwanyanwu, Okey; Kazembe, Peter N; Tansuphasawadikul, Somsit; Eampokalap, Boonchuay; Chaovavanich, Achara; Reller, L Barth; Jarvis, William R; Hall, Gerri S; Procop, Gary W

    2004-01-01

    Susceptibility profiles of medically important fungi in less-developed countries remain uncharacterized. We measured the MICs of amphotericin B, 5-flucytosine, fluconazole, itraconazole, and ketoconazole for Cryptococcus neoformans clinical isolates from Thailand, Malawi, and the United States and found no evidence of resistance or MIC profile differences among the countries.

  7. India, Genomic diversity & Disease susceptibility

    Indian Academy of Sciences (India)

    Table of contents. India, Genomic diversity & Disease susceptibility · India, a paradise for Genetic Studies · Involved in earlier stages of Immune response protecting us from Diseases, Responsible for kidney and other transplant rejections Inherited from our parents · PowerPoint Presentation · Slide 5 · Slide 6 · Slide 7.

  8. Linking social and vocal brains: could social segregation prevent a proper development of a central auditory area in a female songbird?

    Directory of Open Access Journals (Sweden)

    Hugo Cousillas

    Full Text Available Direct social contact and social interaction affect speech development in human infants and are required in order to maintain perceptual abilities; however the processes involved are still poorly known. In the present study, we tested the hypothesis that social segregation during development would prevent the proper development of a central auditory area, using a "classical" animal model of vocal development, a songbird. Based on our knowledge of European starling, we raised young female starlings with peers and only adult male tutors. This ensured that female would show neither social bond with nor vocal copying from males. Electrophysiological recordings performed when these females were adult revealed perceptual abnormalities: they presented a larger auditory area, a lower proportion of specialized neurons and a larger proportion of generalist sites than wild-caught females, whereas these characteristics were similar to those observed in socially deprived (physically separated females. These results confirmed and added to earlier results for males, suggesting that the degree of perceptual deficiency reflects the degree of social separation. To our knowledge, this report constitutes the first evidence that social segregation can, as much as physical separation, alter the development of a central auditory area.

  9. Brain Aneurysm

    Science.gov (United States)

    A brain aneurysm is an abnormal bulge or "ballooning" in the wall of an artery in the brain. They are sometimes called berry aneurysms because they ... often the size of a small berry. Most brain aneurysms produce no symptoms until they become large, ...

  10. Brain Development

    Science.gov (United States)

    ... Become a Member Home Early Development & Well-Being Brain Development A child’s brain undergoes an amazing period of development from birth ... neural connections each second. The development of the brain is influenced by many factors, including a child’s ...

  11. Left Brain. Right Brain. Whole Brain

    Science.gov (United States)

    Farmer, Lesley S. J.

    2004-01-01

    As the United States student population is becoming more diverse, library media specialists need to find ways to address these distinctive needs. However, some of these differences transcend culture, touching on variations in the brain itself. Most people have a dominant side of the brain, which can affect their personality and learning style.…

  12. Antifungal susceptibility testing method for resource constrained laboratories

    Directory of Open Access Journals (Sweden)

    Khan S

    2006-01-01

    Full Text Available Purpose: In resource-constrained laboratories of developing countries determination of antifungal susceptibility testing by NCCLS/CLSI method is not always feasible. We describe herein a simple yet comparable method for antifungal susceptibility testing. Methods: Reference MICs of 72 fungal isolates including two quality control strains were determined by NCCLS/CLSI methods against fluconazole, itraconazole, voriconazole, amphotericin B and cancidas. Dermatophytes were also tested against terbinafine. Subsequently, on selection of optimum conditions, MIC was determined for all the fungal isolates by semisolid antifungal agar susceptibility method in Brain heart infusion broth supplemented with 0.5% agar (BHIA without oil overlay and results were compared with those obtained by reference NCCLS/CLSI methods. Results: Comparable results were obtained by NCCLS/CLSI and semisolid agar susceptibility (SAAS methods against quality control strains. MICs for 72 isolates did not differ by more than one dilution for all drugs by SAAS. Conclusions: SAAS using BHIA without oil overlay provides a simple and reproducible method for obtaining MICs against yeast, filamentous fungi and dermatophytes in resource-constrained laboratories.

  13. Slope failure susceptibility zonation using integrated remote sensing ...

    Indian Academy of Sciences (India)

    61

    In view of the above, hazard assessment was necessary to identify area with ... Singrauli coalfield and surrounding regions comprise of two distinct .... highwall slope failure susceptibility zonation was done using multi-layered ... iii) generation of false colour composites (band combinations and ratioing) iv) generation of.

  14. Effect of municipal liquid waste on corrosion susceptibility of ...

    African Journals Online (AJOL)

    This investigation studied the effect of municipal liquid waste discharged into the environment within Kano municipal area on the corrosion susceptibility of galvanized steel pipe burial underground. Six stagnant and six moving municipal liquid waste samples were used for the investigation. The corrosion rate of the ...

  15. Grey matter correlates of susceptibility to scams in community-dwelling older adults.

    Science.gov (United States)

    Duke Han, S; Boyle, Patricia A; Yu, Lei; Arfanakis, Konstantinos; James, Bryan D; Fleischman, Debra A; Bennett, David A

    2016-06-01

    Susceptibility to scams is a significant issue among older adults, even among those with intact cognition. Age-related changes in brain macrostructure may be associated with susceptibility to scams; however, this has yet to be explored. Based on previous work implicating frontal and temporal lobe functioning as important in decision making, we tested the hypothesis that susceptibility to scams is associated with smaller grey matter volume in frontal and temporal lobe regions in a large community-dwelling cohort of non-demented older adults. Participants (N = 327, mean age = 81.55, mean education = 15.30, 78.9 % female) completed a self-report measure used to assess susceptibility to scams and an MRI brain scan. Results indicated an inverse association between overall grey matter and susceptibility to scams in models adjusted for age, education, and sex; and in models further adjusted for cognitive function. No significant associations were observed for white matter, cerebrospinal fluid, or total brain volume. Models adjusted for age, education, and sex revealed seven clusters showing smaller grey matter in the right parahippocampal/hippocampal/fusiform, left middle temporal, left orbitofrontal, right ventromedial prefrontal, right middle temporal, right precuneus, and right dorsolateral prefrontal regions. In models further adjusted for cognitive function, results revealed three significant clusters showing smaller grey matter in the right parahippocampal/hippocampal/fusiform, right hippocampal, and right middle temporal regions. Lower grey matter concentration in specific brain regions may be associated with susceptibility to scams, even after adjusting for cognitive ability. Future research is needed to determine whether grey matter reductions in these regions may be a biomarker for susceptibility to scams in old age.

  16. Susceptibility assessment of debris flows using the analytic hierarchy process method − A case study in Subao river valley, China

    Directory of Open Access Journals (Sweden)

    Xingzhang Chen

    2015-08-01

    Full Text Available Many debris flows have occurred in the areas surrounding the epicenter of the Wenchuan earthquake. Susceptibility assessment of debris flows in this area is especially important for disaster prevention and mitigation. This paper studies one of the worst hit areas, the Subao river valley, and the susceptibility assessment of debris flows is performed based on field surveys and remote sensing interpretation. By investigating the formation conditions of debris flows in the valley, the following assessment factors are selected: mixture density of landslides and rock avalanches, distance to the seismogenic fault, stratum lithology, ground roughness, and hillside angle. The weights of the assessment factors are determined by the analytic hierarchy process (AHP method. Each of the assessment factors is further divided into five grades. Then, the assessment model is built using the multifactor superposition method to assess the debris flow susceptibility. Based on the assessment results, the Subao river valley is divided into three areas: high susceptibility areas, medium susceptibility areas, and low susceptibility areas. The high susceptibility areas are concentrated in the middle of the valley, accounting for 17.6% of the valley area. The medium susceptibility areas are in the middle and lower reaches, most of which are located on both sides of the high susceptibility areas and account for 45.3% of the valley area. The remainders are classified as low susceptibility areas. The results of the model are in accordance with the actual debris flow events that occurred after the earthquake in the valley, confirming that the proposed model is capable of assessing the debris flow susceptibility. The results can also provide guidance for reconstruction planning and debris flow prevention in the Subao river valley.

  17. Brain neurotransmitters and hippocampal proteome in pigs under stress and environmental enrichment

    Directory of Open Access Journals (Sweden)

    Laura Arroyo

    2017-06-01

    Full Text Available Stress and wellbeing are psychological conditions that are mediated by the central nervous system. In the brain, stress is mediated mainly by the hypothalamus, which will activate the hypothalamic-pituitary-adrenal (HPA axis, leading to the secretion of cortisol, the paradigmatic stress hormone. Other brain areas as the amygdala, the hippocampus or the prefrontal cortex (PFC are involved in emotions such as happiness, anxiety and fear. Communication between brain areas is achieved by chemical neurotransmitters (NTs, which are secreted by presynaptic neurons to reach postsynaptic neurons, where they will cause a variation in membrane polarization and other cell signaling actions, leading to physiological responses. Amongst these NTs, catecholamines (noradrenaline and dopamine and serotonin play an important role. On the other hand, the adverse effects of stress may be counteracted by housing the individuals under environmental enrichment conditions. This long-term situation should have an effect, not only on NTs, but also on the brain proteome. Under the hypothesis that different stress situations will lead to changes in NT composition that will be specific for crucial brain areas, we have tested the effects of transport stress, handling stress at the slaughterhouse, and the stress-susceptible genotype (Ryr1 on the amine NT concentration in amygdala, hippocampus, PFC and hypothalamus of pigs. The effects of living under environmentally enriched or control conditions on the NT concentration in several brain regions and on the hippocampus proteome has been also analyzed. In conclusion, genetic factors as well as management conditions related to housing, transport and slaughterhouse alter in different degree the catecholaminergic and the serotoninergic neurotransmission in the brain, and give clues about how different individual types are able to react to external challenges. Likewise, environmental enrichment leads to changes in the proteome